A cooking surface for a cooktop. Encrusted, spilled, or overflowing food is deposited on the cooking surfaces of cooktops during cooking and the removal of such residue is difficult because the surface of a cooktop is typically rough and uneven. The invention teaches the manufacture of an easy-to-clean glass ceramic cooktop from a floated glass ceramic. As a result of the increased use of controls in cooking devices, an increased number of displays are also being used under the surface of the cooktops. The invention provides a cooktop with a smooth, distortion-free surface that is easy to clean. The invention also relates to window panes for enclosed hot areas with high temperatures, which are typically made of transparent glass ceramic. When used as windows in warming stoves or in self-cleaning ovens, combustion residues are thereby deposited on the windows, which residues must then be removed. It is difficult to clean a window of this type, because the surface of the transparent glass ceramic that is manufactured using conventional methods is typically structured and uneven. The invention teaches the manufacture of an easy-to-clean class ceramic window body from a floated glass ceramic that has a specified surface quality that is comparable to that of a floated soda lime glass pane. The invention also relates to a stove for cooking food with an easy-to-clean oven window and an easy-to-clean cooktop.

1. Field of the Invention
This invention relates to an easy-to-clean glass ceramic cooktop, preferably for use as a cooking surface for a cooktop such as on kitchen stoves, and in particular for self-cleaning ovens or warming stoves. This invention further relates to an easy-to-clean glass ceramic window, preferably for use as a window for oven doors, such as on kitchen stoves, and in particular for windows on self-cleaning ovens or warming stoves.
2. Background of the Invention
Glass ceramic plates for glass ceramic cooking surfaces such as cooktops are typically difficult to clean because the surface contains uneven spots and pits or pores in which spilled or encrusted food gathers during cooking. The food particles are difficult to remove. Even when the cooking surface is cleaned with a scraper, residue is left behind in the pits. The uneven spots on the cooking surface also minimize energy transmission from the heating source of the cooking surface to a cooking utensil such as a pot or pan because air cushions are formed between the cooking surface and the bottom of a cooking utensil. Thus, cooking time is increased, thereby decreasing the efficiency of the cooktop.
Another disadvantage of typically manufactured cooking surfaces of cooktops is that the underside of the cooking surface contains dimples that create distortion. In addition, dimples make the installation of displays and sensors difficult.
The cooking surface can be made smooth by grinding and polishing or by the application of a coating, but these additional steps increase the cost of manufacturing of the cooking surface.
Glass ceramic plates for glass ceramic cooking surfaces such as cooktops are typically manufactured by rolling Lixe2x80x94Alxe2x80x94Si glass (xe2x80x9cgreen glassxe2x80x9d), which is then ceramized. The glass ceramic material has a red to red-brown color or is transparent with a non-transparent coating on the underside. As a result of the rolling, the glass ceramic plate acquires a surface that has uneven spots from which it is difficult to remove dirt particles that typically originate from spilled or overflowing food being cooked. When decoration is applied to the cooking surfaces, individual areas of the decor also stick up and are the first parts to be rubbed off when mechanical stress is applied. The surface of the cooking surface is also not flat.
The Ra of the roughness (arithmetic mean of the absolute height differences from the center plane) is 0.35 xcexcm to 0.55 xcexcm. In spite of this roughness, a scraper blade is the most effective cleaning agent. It cleans better than sponges and cleaning agents with abrasive particles. However, it leaves residues behind in the xe2x80x9cdepressionsxe2x80x9d.
The glass ceramic plates have a deviation from flatness of up to xc2x10.4 mm and a size of 300xc3x97300 mm. The resulting distortions of the images of long sources of light such as fluorescent tubes are noticeable, however, and adversely affect the high-quality image of the product.
The uneven spots are also disadvantageous with regard to energy transmission. The energy transmission to the pots and pans on cooking units with glass ceramic cooking surfaces is primarily by thermal transmission. Only the transport of heat from the spiral-wound heating coil to the underside of the cooking surface occurs by radiation. As a result of uneven spots, air cushions are formed between the cooking surface and the bottom of the pot that increase the time required for cooking. They also lead to an increase in the surface temperature, as a result of which losses to the environment increase and the efficiency decreases.
Typically, the underside of the cooking surface is provided by means of a patterned roller with a dimpling that has a wavelength of approximately 2 mm and a dimple height of 50 xcexcm to 200 xcexcm.
The dimples on the underside also make it impossible to successfully use heating elements that require thermal contact.
As a result of the increased use of electronic controls in cooking devices, an increased number of displays are also being used. To preserve the smooth, flat impression of the unit, these displays are installed under the glass ceramic. On account of the dimpling of the material, these displays are visible only with distortions.
The installation of sensors on the underside is made more difficult by the dimpling, because when the screen printing process is used, it is impossible to achieve a uniform coating thickness. When the sensors on the dimpled side are pressed, the thermal contact is also poor.
A smooth surface of a cooktop made of glass ceramic can be achieved in the manner of the prior art, for example, by grinding followed by polishing. Typically, the preliminary grinding is done with a grain size of approximately 100 xcexcm. The preliminary grinding is followed by grinding with a grain size of 12-15 xcexcm. The final polishing is done with an even finer grain size.
A smooth surface can also be produced in the manner of the prior art by means of a coating. For example, there are transparent glass ceramics that have a heat-reflecting coating, e.g. SnO2. The prior art also discloses the use of SiO2 as a protective coating on a glass ceramic cooktop. Both coatings make the surface smooth and facilitate cleaning, among other things.
Although the methods of the prior art described above do produce a cooktop made of glass ceramic that has a smooth surface, they require additional steps after the manufacture of the glass ceramic cooktop that increase the manufacturing costs for the cooktop.
Windows for enclosed heated areas where the temperature exceeds 350xc2x0 C. are typically made of transparent glass ceramic. When such windows are used as oven door windows for heating stoves or in pyrolysis ovens, combustion residues are deposited on the windows and have to be removed. Commercial cleaning agents, cloths, sponges and scrapers are used to clean the windows.
It is difficult to clean a window of this type. Residue often remains on the window and cannot be removed. This difficulty of removal is caused by the composition of the residues and/or by the surface characteristics of the glass ceramic.
The surface of the transparent glass ceramic that is manufactured using conventional methods is typically structured and uneven. It is similar to an orange peel and generally has a surface with a Ra (arithmetic mean of the absolute height differences from the center plane) of 0.35 xcexcm to 0.55 xcexcm. This macroscopic structure also contains small isolated holes or depressions, pores, or pits, or elevations that have a diameter of up to 0.5 mm. The dirt accumulates in the depressions as well as behind the elevations of the surface and can no longer be removed mechanically. Mechanical cleaning using special cleaning scrapers and sponges is of only limited effectiveness for this purpose. Nevertheless, the best cleaning results are frequently achieved with a sponge and scraper, because, given the composition of the combustion residue, commercial chemical cleaning agents are no longer effective.
These cleaning problems do not occur on a window made of glass ceramic that has a smooth surface on at least one side.
A smooth surface of a window made of glass ceramic can be achieved in the manner of the prior art, for example, by grinding followed by polishing. Typically, the preliminary grinding is done with a grain size of approximately 100 xcexcm. The preliminary grinding is followed by grinding with a grain size of 12-15 xcexcm. The final polishing is done with an even finer grain size.
A smooth surface can also be produced in the manner of the prior art by means of a coating. For example, there are transparent glass ceramics that have a heat-reflecting coating, e.g. SnO2. The prior art also discloses the use of SiO2 as a protective coating on a glass ceramic window. Both coatings make the surface smooth and facilitate cleaning, among other things.
Although the methods of the prior art described above do produce a window made of glass ceramic that has a smooth surface, they require additional steps after the manufacture of the glass ceramic window that increase the manufacturing costs for the window.
As mentioned, the situation is similar for the manufacture of a glass ceramic plate that is used as a cooking surface of a cooktop.
This invention relates to an easy-to-clean glass ceramic object for household use, preferably for use as a cooking surface for a cooktop or as a window for oven doors, such as on kitchen stoves, and in particular for windows on pyrolysis ovens or heating stoves.
The invention also relates to window panes for enclosed hot areas with temperatures  greater than 350xc2x0 C., e.g. in self-cleaning ovens, which are typically made of transparent glass ceramic. When used as windows in heating stoves or in pyrolysis ovens, combustion residues are thereby deposited on the windows, which residues must then be removed. It is difficult to clean a window of this type, because the surface of the transparent glass ceramic that is manufactured using conventional methods is typically structured and uneven.
The invention further relates to a cooking surface for a cooktop. Encrusted, spilled, or overflowing food is deposited on the cooking surfaces of cooktops during cooking and the removal of such residue is difficult because the surface of a cooktop is typically rough and uneven. The invention teaches the manufacture of an easy-to-clean glass ceramic cooktop from a floated glass ceramic.
The invention teaches the manufacture of an easy-to-clean class ceramic window body from a floated glass ceramic that has a specified surface quality that is comparable to that of a floated soda lime glass pane.
The object of the invention is to create a glass ceramic surface for a cooktop that is easy to clean and that has a smooth and, therefore, easy-to-clean surface even without additional manufacturing steps such as polishing or coating.
Another object of the invention is to create a glass ceramic window for an oven or stove that is easy to clean and that has a smooth and, therefore, easy-to-clean surface even without additional manufacturing steps such as polishing or coating.
Another object of the invention is to create a glass ceramic object that is easy to clean and that has a smooth and, therefore, easy-to-clean surface even without additional manufacturing steps such as polishing or coating.
The invention teaches that this object can be accomplished by an easy-to-clean glass ceramic object, comprising a floated glass ceramic that directly and without additional polishing has a surface structure that has a roughness determined by the average roughness Raxe2x89xa60.02 xcexcm and/or the square average roughness Rqxe2x89xa60.01 xcexcm.
As a result of the measures claimed by the invention, it is possible to obtain a glass ceramic object with a very smooth surface structure that is identical to the surface of soda lime float glass. There is essentially no need for additional fine grinding or for coating. The structure of the surface is easily controlled from the very beginning of the process by an appropriate selection of the composition and the manufacturing method of the glass ceramic.
The green glass, i.e. the primary glass used for the object to be ceramized, is manufactured using the float process. As a result, the green glass has a smooth, flat surface. This surface remains smooth and flat during the subsequent ceramization, and on glass ceramic plates for cooking surfaces it also remains smooth and flat during the decoration process. The fine corrugations that are unavoidably formed when the glass is manufactured by rolling do not form in floated material and, as a result, the upper side of the glass is particularly flat and smooth.
As a result of the smooth surface, floated ceramic objects manufactured as claimed by the invention are easy to clean. When these glass ceramic objects are used as windows in oven doors, it is easy to remove condensed vapors as well as pyrolysis residues and similar substances. When these glass ceramic objects are used as glass ceramic cooking surfaces, it is easy to remove encrusted, spilled, or overflowed food. Cleaning using a blade scraper therefore leaves essentially no residue.
The cooking surfaces manufactured from the glass ceramic claimed by the invention have a deviation from flatness of xc2x10.03 mm, which is typical for float glass, with reference to a format of 300xc3x97300 mm (compared to 0.4 mm for rolled material). On account of their better flatness, such surfaces are characterized by a particularly advantageous optical impression with regard to the reflection of light sources in the kitchen or from the outdoors. Moreover, the decorative coating, which is conventionally approximately 5 xcexcm thick on glass ceramic cooking surfaces, is oriented in a plane, on account of the absence of fine corrugations. Because there are no elevated areas, the uneven wear of the decoration under mechanical load is prevented. Consequently, the decoration does not become xe2x80x9ccloudyxe2x80x9d after extended use.
The transmission of energy is also improved.
The terms used to describe surface roughness are defined in, among other places, German standard DIN 4762. For example, the average roughness Ra is the arithmetic mean or average of the absolute height differences from the center plane or the arithmetic average of the absolute amounts of the differences between the actual or measured profile and the average profile. This average profile is calculated by laying a profile through the measured profile within a reference length, so that the sum of the surface area of the measured profile filled with material on the top and the sum of the surface areas free of materials on the bottom are equal. On the basis of DIN 4762, Rq=square average roughness, determined by means of white light interference microscopy (measurement area 0.6xc3x970.5 mm). In terms of formulas, this concept is expressed as follows:             R      a        =                  (                              "LeftBracketingBar"                          Z              1                        "RightBracketingBar"                    +                      "LeftBracketingBar"                          Z              2                        "RightBracketingBar"                    +                      "LeftBracketingBar"                          Z              3                        "RightBracketingBar"                    +          …          +                      xe2x80x83                                          "LeftBracketingBar"                          Z              n                        "RightBracketingBar"                          )            N                  R      q        =                            (                                    Z              1              2                        +                          Z              2              2                        +                          Z              3              2                        +            …                                      xe2x80x83                        +                          Z              n              2                                )                N
The manufacture of flat glass ceramic objects is described by the prior art.
To simplify the manufacture of such glass ceramics using float glass as the primary material, attempts have been made to perform the ceramization as early as in the float bath as possible, to thereby obtain the glass ceramics directly. In such a process, defects in the float glass, in particular undesirable surface crystals that occur during the floating, cannot be detected and eliminated, which disadvantage has an adverse effect on the surface quality of the float glass.
Theoretically, all glass ceramics floated according to the methods of the prior art can be used for the manufacture of the easy-to-clean glass ceramic object claimed by the invention.
To achieve a particularly good surface quality and thus a correspondingly high ease of cleaning, the initial glass used for the glass ceramic is a float glass, in which the origin of undesirable surface defects during the floating is prevented by restricting the concentrations of Pt to  less than 300 ppb, Rh to  less than 3.0 ppb, ZnO to  less than 1.5 wt. and SnO2 to  less than 1 wt. %, and by fining or refining the glass during the melting without using the conventional fining agents arsenic oxide or antimony oxide.
These types of glass are therefore characterized by a composition that makes it possible to prevent the formation of undesirable surface defects during floating. Floats conventionally consist of the melting chamber or hot end, in which the glass is melted and fined or refined, an interface that provides the transition from the oxide atmosphere in the melting chamber into the reducing atmosphere in the rest of the system, and the float portion, in which the glass is shaped by pouring it onto a molten metal, generally Sn, in a reducing atmosphere of forming gas. The glass is formed by allowing it to flow out smoothly onto the Sn bath and by top rollers that exert a force on the surface of the glass. During the transport on the metal bath, the glass cools, and at the end of the float portion it is lifted off and transferred into a cooling furnace or lehr or annealing furnace/oven.
During the formation of the glass surface and the transport in the float, interactions between the glass and the float atmosphere or the Sn batch can result in undesirable surface defects.
If the glass contains more than 300 ppb Pt or more than 30 ppb Rh in dissolved form, metallic precipitations of Pt or Rh particles can form as a result of the reducing conditions in the glass surface, and these particles can serve as effective seeds for large high quartz or beta quartz mixed crystals up to 100 xcexcm large, and thus cause undesirable surface crystallization.
These materials are used in, among other things, electrodes, linings, agitators, transport tubes, valve gates etc. In plants for the performance of the method for the manufacture of the glass ceramic described above, to prevent the formation of surface crystals, therefore, components that contain Pt or Rh are completely avoided and are replaced by ceramic materials, or the conditions in the melting chamber or interface are realized so that the above-mentioned concentrations are not exceeded.
The ZnO concentration is restricted to 1.5 wt. %. It has been shown that under the reducing conditions of the floating, the zinc is depleted in the surface of the glass. It is thereby assumed that the zinc is partly reduced on the surface of the glass, whereupon it vaporizes as a result of the higher vapor pressure of Zn compared to Zn2+ in the float atmosphere. In addition to the evaporation and deposition of the Zn in colder spots, which are undesirable for the operation of the float, the uneven distribution of the Zn in the glass also participates in the origin of critical crystal bands close to the surface. These crystal bands of large high or beta quartz mixed crystals originate in the vicinity of the surface where the Zn concentration in the glass has risen back close to the initial value. It is therefore appropriate to keep the initial value low from the start.
The concentration of SnO2 in the glass is restricted to less than 1 wt. %. As a result of the action of the reducing conditions in the float portion, the SnO2 is partly reduced, especially in the surface of the glass. Surprisingly, small metal Sn spheres form in the glass in the immediate surface of the glass, and although they can easily be removed during cooling or cleaning, they leave behind spherical holes or pits or depressions that are extremely undesirable for the intended use of the glass.
These small spheres can be prevented if the concentration of SnO2 is very low.
The above-mentioned primary glasses are fined or refined without using the fining agents arsenic oxide and/or antimony oxide which are conventional for glass from the Li2Oxe2x80x94Al2O3xe2x80x94SiO2 system. Under the action of the reducing conditions during floating, the above mentioned fining agents in particular are reduced directly on the surface of the glass and form undesirable and visible metallic coatings. The removal of these coatings, which are aesthetically and toxicologically undesirable, requires grinding and polishing and is disadvantageous for economic reasons. To prevent the formation of the coatings, it is therefore appropriate to achieve a low seed number or number of seeds or number of bubbles by adding at least one alternative chemical fining agent, such as SnO2, CeO2, sulfate compounds, chloride compounds, for example, preferably 0.2-0.6 wt. % SnO2, to the molten glass. Alternatively, the molten glass can also be fined physically, e.g. by means of underpressure or by means of high temperature  greater than 1750xc2x0 C. Thus the required seed quality or number of bubbles can be achieved by means of alternative fining agents and/or alternative fining methods.
During the ceramization, care must be taken to avoid any adverse effect on the low roughness values achieved by floating, for example by conducting the ceramization vertically or by an air-cushion ceramization, i.e. generally without any contact between the glass object being ceramized and a substrate.
Special advantages with regard to a very low surface roughness of the glass ceramic are achieved by a floated, ceramized aluminosilicate glass with the following composition in wt. % on an oxide basis: Li2O comprising three and two tenths to five weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; Na2O comprising zero to one and five tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; K2O comprising zero to one and five tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; xcexa3Na2O+K2O comprising two tenths to two weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; MgO comprising one tenth to two and two tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; CaO comprising zero to one and five tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; SrO comprising zero to one and five tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; BaO comprising zero to two and five tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; ZnO comprising zero to less than one and five tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; Al2O3 comprising nineteen to twenty-five weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; SiO2 comprising fifty-five to sixty-nine weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; TiO2 comprising one to five weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; ZrO2 comprising one to two and five tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; SnO2 comprising zero to less than one and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; xcexa3TiO2+ZrO2+SnO2 comprising two and five tenths to five weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; P2O5 comprising zero to three weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range.
In a second realization, the glass in one particularly preferred embodiment has a composition, in wt. % on an oxide basis, of: Li2O comprising three and five tenths to four and five tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; Na2O comprising two tenths to one weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; K2O comprising zero to eight tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; xcexa3Na2O+K2O comprising four tenths to one and five tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; MgO comprising three tenths to two weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; CaO comprising zero to one weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; SrO comprising zero to one weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; BaO comprising zero to two and five tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; ZnO comprising zero to one and weight percent within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; Al2O3 comprising nineteen to twenty-four weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; SiO2 comprising sixty to sixty-eight weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; TiO2 comprising one to two weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; ZrO2 comprising one and two tenths to two and two tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; SnO2 comprising zero to six tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; xcexa3TiO2+ZrO2+SnO2 comprising three to four and five tenths weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range; P2O5 comprising zero to two weight percent and within the range percentages in tenth of percent steps such that any tenth of a percent may be a limit of a diminished range.
This glass is used with particular advantage for the manufacture of the glass ceramic object claimed by the invention, because the corresponding surface is very easy to clean.
The glass ceramic object claimed by the invention can be used wherever ease of cleaning is necessary. It can be used for, among other things, oven door windows, in particular windows for doors for kitchen stoves, or for glass ceramic cooking surfaces of cooktops.
The above-discussed embodiments of the present invention will be described further herein below. When the word xe2x80x9cinventionxe2x80x9d is used in this specification, the word xe2x80x9cinventionxe2x80x9d includes xe2x80x9cinventionsxe2x80x9d, that is, the plural of xe2x80x9cinventionxe2x80x9d. By stating xe2x80x9cinventionxe2x80x9d, the Applicants do not in any way admit that the present application does not include more than one patentably and non-obviously distinct invention, and maintains that this application may include more than one patentably and non-obviously distinct invention. The Applicants hereby assert that the disclosure of this application may include more than one invention, and, in the event that there is more than one invention, that these inventions may be patentable and non-obvious one with respect to the other.

Cooking arrangement for cooking food such as a stove, a cooktop, and other cooking appliances, with an easy-to-clean surface


A display panel includes a first substrate, a second substrate, and a liquid crystal layer. The first substrate includes a switching element connected to a gate line and a data line crossing each other, and a pixel electrode electrically connected to the switching element. The pixel electrode includes a first domain-dividing portion extending in a direction. The second substrate is spaced apart from the first substrate to have a cell gap of about 3.1 μm to about 3.3 μm. The second substrate includes a common electrode including a second domain dividing portion formed in a region between the first domain-dividing portions adjacent to each other. The liquid crystal layer is interposed between the first and second substrates. The liquid crystal layer includes a liquid crystal composition having a refractive anisotropy (Δn) of about 0.1010 to about 0.1030.

1. Field of the Invention
The present invention relates to a display panel. More particularly, the present invention relates to a display panel used in a liquid crystal display ("LCD") device.
2. Description of the Related Art
Generally, a liquid crystal display ("LCD") device includes an LCD panel for displaying an image and a backlight assembly for providing the LCD panel with light. The LCD panel includes a thin-film transistor ("TFT") substrate having a switching element to drive a pixel, an opposing substrate facing the TFT substrate, and a liquid crystal layer interposed between the TFT substrate and the opposing substrate. An image is displayed on the LCD panel depending upon the light transmittance of the liquid crystal material, which changes according to the voltages applied to the pixel.
Operation modes of the LCD device for displaying an image are classified according to the directional arrangement of liquid crystal molecules. Examples of the operation modes may include a twisted nematic ("TN") mode, an in-plane switching ("IPS") mode, a vertical alignment ("VA") mode, and the like.
The VA mode may include a patterned vertical alignment ("PVA") mode dividing a pixel into multiple domains in order to facilitate a wide viewing angle. In the PVA mode, a pixel electrode includes a first opening portion, and a common electrode includes a second opening portion not coinciding with the first opening portion, to thereby change the direction of a fringe field between the pixel electrode and the common electrode. The arrangement of the liquid crystal molecules is changed by the direction of the fringe field, so that the liquid crystal molecules are divided into the multiple domains.
However, when an LCD device operating in the PVA mode includes the first and second opening portions, the aperture ratio of the PVA mode may be lower than that of the VA mode. The aperture ratio is generally proportional to a light transmittance ratio, and thus the light transmittance ratio of the PVA mode is lower than that of the VA mode. Thus, when an LCD device is operated in the PVA mode, the display quality may be reduced despite the wide viewing angle.


An axial lead frame including two side rails arranged opposite to each other and plural pairs of lead terminals separated from each other and located opposite to each other, in which a longer lead terminal and a shorter lead terminal of a pair of the lead terminals are alternately arranged to extend in parallel with each other in the equally spaced relationship between both side rails. And, a buffer member is formed at the substantially central part between both the side rails so as to allow the longer lead terminals extending from both the side rails toward the buffer member to be jointed to each other along the buffer member. A die pad is die-bonded to the foremost end of each of the longer lead terminal, while a pad is placed at the foremost end of each of the shorter lead terminal. Dam bars are bridged between adjacent lead terminals in order to prevent molten resin from flowing out during molding operation.

The present invention relates generally to an axial lead frame. More particularly, the present invention relates to a contour to be assumed by an axial lead frame which is used for the purpose of producing electronic components each having two poles located opposite to each other, e.g., diode devices, light emitting diode devices or the like.
A contour assumed by a conventional axial lead frame (hereinafter referred to simply as a lead frame) of the foregoing type will be described below with reference to FIG. 3 with respect to a lead frame to be used for producing diode devices.
The lead frame designated by reference numeral 1 includes two side rails 3 and 4 located opposite to each other, and a plurality of joint pieces 2 arranged in the equally spaced relationship in the longitudinal direction are bridged between both the side rails 3 and 4. In addition, a predetermined number of lead terminals 5 and 6 (each six terminals in the shown case) separated from each other and located opposite to each other are arranged in the equally spaced relationship to extend in parallel with each other in each segment defined by adjacent joint pieces 2. A die pad 7 is formed at the foremost end of each lead terminal 5 for the purpose of die-bonding a diode element thereto, while a pad 8 is formed at the foremost end of each lead terminal 6 for the purpose of connecting thereto one end of a fine metallic lead wire connected to the corresponding diode element. Generally, the lead frame 1 contoured in the aforementioned manner is produced by employing a punching process using a punching die.
Next, a procedure of producing a diode device using the lead frame 1 will be described below.
First, a diode element is die-bonded to each die pad 7, and subsequently, the diode element die-bonded in that way is connected to the corresponding pad 8 via a fine metallic lead wire. On completion of the connecting operation, an assembly consisting of one segment of the lead frame 1, diode elements die-bonded to pads 8 and fine metallic lead wires is subjected to molding as illustrated by phantom lines R in FIG. 3. To test electrical properties of each diode device produced in that way, one of the lead terminals 5 or 6 is cut off from the side rail 3 or 4. Testing is executed with the diode device by connecting a common measuring pin to the side rail 3 or 4 which holds lead terminals 5 or 6 without any connection to the diode device and then connecting another measuring pin to the lead 5 or 6 which is cut off therefrom. On completion of the testing, the lead terminal 5 or 6 which is not connected to the diode device which has been confirmed as an acceptable one is cut off from the side rail 3 or 4.
With resect to the conventional lead frame constructed in the above-described manner, however, the following problems have been arisen.
With the conventional lead frame 1, a plurality of joint pieces 2 should be arranged in the equally spaced relationship in the longitudinal direction for connecting the side rails 3 and 4 to each other which hold plural pairs of lead terminals 5 and 6 separated from each other. For this reason, the number of diode devices obtainable per a unit length of the lead frame 1 is unavoidably restricted. Thus, there arises a problem that each diode device is produced not only at an expensive material cost but also at an expensive production cost. When each joint piece 2 is designed to have a smaller width or a pitch between adjacent joint pieces 2 is elongated in order to increase the number of diode devices obtainable per a unit length of the lead frame 1, there arises another problem that the joint strength of the lead frame 1 is undesirably reduced.
As mentioned above, the lead frame 1 is generally produced by employing a punching process using a punching die, and the punching die includes punches each adapted to repeatedly punch a pattern enclosed by the phantom lines R (consisting of a single joint piece 2 and plural pairs of lead terminals 5 and 6 arranged in the equally spaced relationship to extend in parallel with each other in the space defined between adjacent joint pieces 2) as shown in FIG. 3. Thus, each lead frame 1 having a plurality of patterns each having a same contour successively arranged in the longitudinal direction is produced by simultaneously punching them from a metallic sheet material in the punching die. Due to the fact that the conventional lead frame 1 includes a plurality of joint pieces 2 arranged in the equally spaced relationship in the longitudinal direction, a pitch between adjacent joint pieces 2 is elongated, and moreover, the number of punches required for the punching die increases correspondingly. Thus, there arises another problem that the punching die becomes complicated in structure, resulting in it being produced at an expensive cost.


Provided is a method for controlling a brushless motor (101) in a power tool system. The brushless motor (101) includes multiple phase windings (u, v, w). The control method includes: operating the brushless motor (101) in each driving state for a period of time separately; measuring a voltage of a higher-voltage one of two phase input ends to which a driving voltage is applied and defining this voltage as a higher-voltage end voltage; measuring a voltage of a phase input end of one of the multiple phase windings which is kept floating when the driving voltage is applied and defining this voltage as a floating end voltage; determining whether values of the higher-voltage end voltage and the floating end voltage meet a preset condition; and when the values of the higher-voltage end voltage and the floating end voltage meet the preset condition, using any one of the multiple phase windings not serving as the current floating phase as a next floating phase. This method helps improve the running efficiency of the brushless motor (101).

Motors are classified into brush motors and brushless motors according to phase commutation methods. The phase commutation of the brush motor is implemented by a commutator and a carbon brush with a rotation of a rotor. For the brushless motor, the phase communication is continuously performed by electronic control so that a winding generates an electromagnetic field whose direction is continuously changing and a rotator rotates under the interaction of a magnetic field and the electromagnetic field.
Brushless motors are classified into an inner-rotor motor and an outer-rotor motor according to a configuration of a rotor and a stator. For both of the inner-rotor motor or the outer-rotor motor, windings can be used as a rotor or a stator.
For a brushless motor, the phase number of the windings, and the number and position of iron cores wound by coils of each phase winding can be designed according to specific requirements. The design principle is to make the coils of each phase winding produce a continuously changing magnetic field in space when each phase winding is energized according to an electrical cycle.
When the simplest two-phase winding motor is electronically controlled, the motor can be driven by switching the states of voltages applied to the two phase windings. Only two phase windings are involved in phase commutation, so, for the electronic control, commutation timing and initial position can be determined in the same way and the control result is either of two phase communication.
When a brushless motor with three phase windings is electronically controlled, the brushless motor has six driving states in one electrical cycle due to the three phase windings, so the driving state to be outputted needs to be determined according to the positon of the rotator when the brushless motor is started. When the brushless motor is normally driven, once the position of the rotator is detected to be changed, phase commutation is performed and another driving state is outputted. Only when a driving state corresponding to the position of the rotator is outputted, can the brushless motor output the maximum torque.
In order to control the brushless motor the position of the rotor needs to be detected. Currently the rotor is detected using two technologies: one is sensory control, that is, a position sensor is used to detect the position of the rotor and generate a control signal; the other is sensorless control, that is, the phase commutation of the brushless motor is controlled according to the position of the rotor and changes of the position which are determined according to changes in electrical parameters of windings.
Sensory control simplifies control logic to make the control more direct. However, when the position of the sensor is inaccurate due to an assembly problem or other problems, the driving of the brushless motor will be affected.
The cost of the sensorless control is lower. In the existing sensorless control, first the rotor is forcedly driven to rotate according to a certain driving state, not according to the position of the rotor. After the rotor rotates at a certain speed, the driving state is gradually switched according to the phase commutation control of the rotor, until a driving state corresponding to the position of the rotator is switched to. Then the normal driving is performed. Although the rotor rotates when being forcedly driven, the brushless motor cannot output enough torque because the driving state does not correspond to the position of the rotor. In addition, this control method relies on that the rotor can rotate at a certain initial speed first. Therefore, when the rotor cannot rotate or is difficult to rotate for some reason, it is difficult to make the brushless motor to be in a correct driving state with such control method.
If the brushless motor is applied to the field of power tool systems, accessories driven by the rotor of the brushless motor tend to make the rotor to bear a load when the rotor is started in the beginning because of locked-rotor (for example, electric pruner and electric chain saw) and the operating conditions (for example, electric screwdriver and electric wrench) when the brushless motor is applied, causing a starting difficult and a low operating efficiency.


Disclosed is an aerostatic air bearing. The disclosed aerostatic air bearing includes: an aerostatic nut, said aerostatic nut including a housing having an air inlet disposed therein, a helical plenum chamber disposed in said housing, said helical plenum chamber being fluidly connected to the air inlet and fluidly interconnecting a plurality of openings, said openings being disposed in a helical pattern, and a plurality of porous media, each of said porous media being disposed in one of the plurality of openings respectively; and a lead screw coupled to said aerostatic nut, said lead screw including a threaded surface separated from each of the plurality of porous media.

(a) Field of the Invention
Exemplary embodiments relate to an aerostatic air bearing, an assembling method thereof, and an aerostatic lead screw actuator using the aerostatic air bearing.
(b) Description of the Related Art
Miniaturization technologies have placed new challenges on the world of manufacturing. Micro-scale machine tools (mMTs) have recently emerged as a viable and economic option to address these challenges.
However, evolving applications for mMTs have begun to include materials that are difficult to machine. For example, hard turning and micro-machining of titanium, stainless steels, and bulk metallic glass are just some challenges faced by mMTs.
These applications require increased static/dynamic stiffness and high damping in the actuators used in mMTs. A prior solution for linear positioning, ball screws, does not generally achieve the positioning accuracy required for mMTs.
Hydrostatic lead screw actuators and aerostatic lead screw actuators have been developed for use in mMTs. Hydrostatic screws are messy and require significant support equipment.
Aerostatic lead screw actuators (ALSAs) have the potential to provide the necessary stiffness as well as extremely high positioning accuracy. ALSAs use an air film in place of balls to transmit the load from the nut (aerostatic lead screw actuators (ALSAs)) to the screw. ALSAs also eliminate backlash and stick-slip friction and therefore appear to be particularly suitable for high performance mMTs. The major challenge posed in the manufacture of an ALSA, however, is maintaining the precise air gap between the screw and the nut over the entire helical threaded surface.
In the art, both orifice-restricted and porous-restricted air bearings have been incorporated in aerostatic lead screw designs. For example, Tachikawa et al., "Ultra Precision Positioning Using Air Bearing Lead Screw," Transactions of the Japan Society of Mechanical Engineers, Vol. 66, No. 645, pp. 1559-1566, 2000, disclose a porous-restricted aerostatic lead screw actuator that achieves 10 nm positioning accuracy. However, this lead screw actuator design provides relatively low stiffness (e.g., 30 N/micron), and requires thread engagement with eight thread revolutions, which significantly increases manufacturing costs.
A design and manufacturing method for a groove-fed orifice-restricted ALSA is disclosed in U.S. Pat. No. 4,836,042 by Slocum et al. Due to the special nature of the thread design in the '042 patent, however, any inaccuracy in the thread profile doubles the error seen in the air gap.
U.S. Pat. No. 5,090,265 by Slocum et al. discloses the use of a hydrostatic lead screw actuator that does not require precise air gap control. The manufacturing process is based on machining both the thread and the nut on the same machine to maximize the repeatability of cutting operations. In the '265 patent, which describes a design and manufacturing method for an orifice-restricted fluid-based lead screw actuator, high pressure air, oil, and other fluids provide a working fluid. The lead screw actuator focuses on orifice-restriction as the primary method to control air flow. These orifices feed grooves that distribute air to the entire thread flank of the lead screw to create an air gap between the nut and the screw.
However, such a focus on orifice-restriction to control airflow is highly susceptible to instability and vibration. Further, the lead screw actuator in the '265 patent is limited to a square thread form, which is not an industry standard. Also, using the manufacturing method presented in the '265 patent, any inaccuracy in the thread profile is doubled where the air gap is concerned. For example, if the thread flank has a slight angle creating an error of 0.5 microns at the outer diameter, this will create an error of 1 micron in the air gap. This property effectively forces the tolerance requirements on a screw made in this way to be halved, thereby increasing manufacturing costs. Still further, using fluids other than air for the '265 patent device requires considerable fluid support equipment, which is less desirable for machine tool applications such as MMT applications.

Aerostatic air bearing, assembling method thereof, and aerostatic lead screw actuator using the same

KOREA INSTITUTE OF MACHINERY & MATERIALS


A capacitance measuring circuit of a touch sensor includes a voltage comparing part, a control part, a complex switch, a charging/discharging circuit part and a timer part. The voltage comparing part outputs a first comparing signal by comparing with a first reference voltage and a sensing voltage of a touch sensor and a second comparing signal by comparing with a second reference voltage and the sensing voltage, in response to a first control signal provided from an external device. The control part outputs a charging/discharging control signal based on the first and second comparing signals, in response to a second control signal provided from an external device. The complex switch is connected to each two terminals of the touch sensors, and is configured to set a path transmitting a sensing signal to the touch sensor and a path receiving a sensing signal sensing a capacitance variation amount of the touch sensor via the touch sensor.

Technical Field
Exemplary embodiments of the present invention relate to a capacitance measuring circuit of a touch sensor and a capacitive touch panel having the capacitance measuring circuit. More particularly, exemplary embodiments of the present invention relate to a capacitance measuring circuit of a touch sensor, which is adapted to a large sized touch screen device having a long length of a touch sensor, for measuring capacitance of the touch sensor more stably and a capacitive touch panel having the capacitance measuring circuit.
Discussion of the Related Art
As electronic engineering technology and information technology have repeatedly advanced, the importance of electronic devices in daily life including a work environment has been steadily increasing. In recent years, the types of electronic devices have diversified. In particular, in the field of portable electronic devices, such as mobile phones and Portable Multimedia Players (PMPs), a vast number of devices with new designs to which new functionalities have been added have been released almost every day.
As the types of electronic devices which people encounter in daily life have gradually diversified and the functionalities of electronic devices have become advanced and complicated, there has been an urgent need for a user interface which users can easily learn and which can be manipulated intuitively.
Touch screen devices have attracted attention as input devices capable of meeting such a need, and have already been widely applied to a variety of electronic devices. A touch screen device is a device that senses the location of a touch of a user on a display screen and performs overall control of the electronic device, including the control of the display screen, using information about the sensed location of the touch as input information.
Methods of sensing the location of a touch on a touch screen device may be divided into discrete location detection and continuous location detection.
Discrete location detection is also referred to as a so-called matrix method, and is a method of dividing a 2D flat surface on a panel into a plurality of sections and sensing the presence of a touch in each of the sections.
In contrast, continuous location detection is a method in which a touch detection area is not divided into a limited number of sections and the location of a touch on a 2D flat surface is sensed in the form of successive values.
A continuous location detection-based touch screen device usually employs a specific algorithm in order to calculate successive coordinates from values measured using a limited number of electrodes.
FIG. 1 is a schematic diagram explaining a conventional continuous location detection-based capacitive touch panel. As shown in FIG. 1, the continuous location detection-based capacitive touch panel determines the location of a contact by sensing a variation in voltage attributable to resistance Rf and capacitance Cf formed in an electrode 10 upon a touch.
The capacitive touch panel includes a detection unit 20 as means for sensing a variation in voltage. In the conventional capacitive touch panel, an input channel 21 for applying a reference signal generated by the detection unit 20 and a reception channel 22 for receiving the reference signal, the voltage of which has varied while passing through an electrode 10, are connected to the first side portion of the electrode via a single conducting wire.
This case is problematic in that the reference signal applied and the signal received after flowing through the electrode 10 use the single conducting wire, so that an error occurs in the measurement of a variation in voltage related to the received signal and thus it is not easy to accurately sense the location of a touch. Here, the error in the measurement of the variation in voltage is proportional to a resistance component which is formed as the length of the electrodes 10 increases.
Accordingly, the conventional capacitive touch panel has the problem of not being applied to large-sized touch screen devices in which the length of electrodes 10 is long.

Capacitance measuring circuit of a touch sensor and capacitive touch panel having the capacitance measuring circuit


A method for producing a beverage or liquid comestible from a single capsule by subdividing the interior of the capsule into a plurality of compartments, at least two compartments containing beverage-forming ingredients, introducing a liquid into one of the compartments of the capsule and starting to produce and drain a first beverage component on the basis of the ingredient contained in the first compartment, and opening a fluid communication between the first and the second compartment such that after the start of the production of the first beverage compartment, a production of a beverage component on the basis of the ingredient contained in the second compartment commences. The capsule is preferably used to make cappuccino-style beverages.

The present invention generally relates to the production of a beverage (e.g. cappuccino, latte macchiato) or a liquid comestible from a capsule, pod, bag or other ingredient-containing container.
Thereby the invention relates to those ingredient-containing containers only which can be placed into a machine (such as e.g. a beverage dispensing machine) in order to have a liquid (usually water) enter the interior of the container.
In the following the background of the invention will be explained referring to a capsule. It is to be understood that the example of the capsule has been chosen as a representative for an ingredient-containing container to be inserted in a beverage or liquid comestible producing machine.
The capsule contains at least one beverage or comestible ingredient. When the ingredient inside the capsule is made to interact with a liquid, for example hot water which is introduced into the interior of the capsule, a beverage can be produced by an interaction of the liquid with the ingredients contained in the capsule. This beverage can then be drained from the capsule.
There is a wide range of possible interactions between the beverage/comestible ingredient(s) and liquid, such as for example extraction, dissolution, brewing, mixing, etc., all of which are encompassed by the present invention even if the following description will focus only on a few of them for illustration purposes.
Typical representatives of such capsules are sealed capsules containing roasted ground coffee powder. Such capsules can be inserted in adapted coffee brewing machines. Once inserted into the coffee brewing machine, water is introduced in the capsule such that the water interacts with the coffee powder contained in the capsule. As a result thereof a coffee beverage is produced, which is outpouring from the capsule and delivered into a recipient (such as a mug, glass, or other) to make the beverage.
Consumers have widely appreciated the convenience of such a beverage production, which is a clean and quick beverage making process and which can be carried out with simple handling; namely essentially consisting of inserting the sealed coffee powder containing capsule in a beverage machine and pressing a button.
Now, especially in the case of coffee specialties (e.g. cappuccino, latte macchiato, or similar beverages) the consumers greatly appreciate the authenticity imparted onto the final beverage cup or glass by the three following elements:
a. The white milk froth covering the top of the beverage,
b. The "stain" of brown coffee marking the spot on the white milk froth phase from where the coffee has been added to the cup, and
c. In the case of a glass receptacle (typical for e.g. latte macchiato as served in bars in Germany), the appearance of three layers with different colours i.e. white at the bottom (liquid milk), brown in the middle (coffee extract), and white (milk froth) on the top.
A single prior art capsule can not deliver a two-phase, multi-layered product whereby two liquid portions coming from two different ingredients are dispensed at different times, for example, to produce a beverage with a milk phase and a coffee phase.
Now, there is a need for a production of beverages which comprises at least two beverage components which are to be produced and filled into a receptacle not simultaneously, but according to a defined time sequence, i.e. at different time periods during the beverage dispensing cycle. A typical example of such a beverage having several sequentially delivered beverage components is cappuccino-style coffee. In order to produce a cappuccino-style coffee, at first milk foam or milk froth is introduced into the receptacle, and only after a certain time period with regard to the start of the milk foam/milk froth filling, a coffee beverage ingredient is poured into the receptacle.
Therefore, according to the prior art, in order to produce, e.g. a cappuccino-style coffee, at first a milk powder or liquid milk containing capsule is inserted, which has then to be replaced by a coffee powder containing capsule. However, this way of preparing a cappuccino-style coffee is not convenient, time consuming as it requires the use of two different capsules.

Beverage ingredient containing capsule having several compartments


A card connector includes a required number of contacts, a housing holding and arranging said contacts therein and having a fitting opening into which the card is inserted, and a switching unit for detecting the insertion and removal of the card. The switching unit includes a first switching terminal and a second switching terminal. When the card is not yet inserted into the connector, the first and second switching terminals contact each other or do not contact each other, and when the card has been inserted into the connector, the first switching terminal is displaced obliquely downward in relation to the inserting direction of the card so that the first and second switching terminals do not contact each other or contact each other, thereby enabling the inserted or removed condition of said card to be detected with great certainty.

This invention relates to a card connector for use in a various kinds of electric or electronic appliances such as printers and card readers, and more particularly to a card connector having a reliable detecting mechanism when a card is inserted and removed into and from the connector.
There have been many kinds of cards as media for a variety of information. It has been a common practice to obtain or accumulate various information from or onto a card which is adapted to be inserted into a card connector connected to an information appliance.
In using a card in such a manner, it is required to insert the card into a card connector with great certainty. Therefore, there is a need to ascertain whether the card has been completely inserted or not. For this purpose switching mechanisms are frequently used.
There have been switching mechanisms for detecting an inserted card into a connector by displacement of one element in a thickness direction (Patent Literature 1), a width direction (Patent Literature 2) or an inserting direction of the connector.
The mechanism for detecting by the displacement of the element in the inserting direction will be explained with FIGS. 5A and 5B. FIG. 5A is a view for explaining a state of switching terminals before inserting a card, while FIG. 5B is a view for explaining a state of the switching terminals when a card has been inserted. As shown in FIGS. 5A and 5B, the card connector 60 of the prior art mainly comprises a housing 62, contacts, and two switching terminals 66 and 68. Prior to the insertion of a card, the two switching terminals 66 and 68 are separated from each other. Upon insertion of a card, first the card will contact the first switching terminals 66 viewed on the lower side in the drawing. On proceeding of the insertion, the first switching terminal 66 moves in the inserting direction of the card (in the upward direction viewed in the drawing) so that the first switching terminal 66 is brought into contact with the second switching terminal 68, thereby detecting the fact that the card has been inserted in the connector.
Japanese Patent Application Opened No. H10-320,511/1998 (Patent Literature 1) discloses a card reader capable of detecting an inserted card by displacement of a switching element in a thickness direction. This card reader has a thin card case so as to obtain a suitable elastic displacement of a switching element and an appropriate contacting force by a slight force for inserting a card into the card reader, thereby achieving good wiping effect and contact caused by pressurized contact and deformation of first and second following switching elements. A card distal end detecting device comprises first and second following switch elements 1 and 2 whose first and second elastic contact pieces 5 and 6 extend along the surface of a memory card and are arranged opposite to the card in its thickness. The first elastic contact piece 5 is so arranged that after an electrode pad arranged on the surface of the inserted card begins to contact the contacts arranged in the card reader, the first elastic contact piece 5 is elastically displaced in the thickness direction of the card by an urging force of the front edge of the card and comes into contact with the second elastic contact piece 6. The second elastic contact piece 6 is so arranged that it is elastically displaced in the thickness direction of the card by an urging force by the first elastic contact piece 5 to perform wiping at the pressurized contact portion.
Japanese Patent Application Opened No. 2001-351,709 (Patent Literature 2) discloses a connector capable of detecting an inserted card by displacement of a switching element in a width direction. This invention has an object to provide a connector into which a plurality of memory cards different in thicknesses can be selectively inserted in order to operate information appliances. The connector includes a connector main body consisting of a rear wall and side walls formed along their full length with receiving portions conforming to side edges of memory cards to be used, card identification terminals in a plurality of rows on the inner surface of one side wall, terminals provided on the rear wall for writing the electronic information and reading the accumulated information onto and from the cards, and protection terminals provided at appropriate positions on the other side wall for prohibiting writing. The card identification terminals are made from a spring-like metal strip piece and arranged in a plurality of rows on the side wall, while identification tabs are arranged on the side wall to separate from the card identification terminals when a card is not inserted. When the identification tabs contact the card identification terminals, the existence of the card is identified.
In recent years, with the miniaturization of the information appliances as well as boards or substrates used therein, surface areas of the boards to be utilized have become extremely narrower. Such a limitation of the surface area of the board leads to the use of a plurality of boards. On the other hand, if a plurality of connectors are required for exchanging a plurality of memory cards, information appliances would become bulky which would be inconvenient for carrying them.
The proposals for detecting the insertion of a card are described above. With the switching mechanisms disclosed in the Patent Literatures 1 and 2, however, there would be clearances between a card and a card fitting opening of a connector. Therefore, if the card is inserted into the fitting opening in a state that one edge of the card on the side of the switch is closer to the side wall of the fitting opening than the other edge to the other side wall, then the insertion of the card would be prematurely identified prior to the complete insertion of the card. For the purpose of overcoming this problem, if the clearance between the card and the fitting opening is made as little as possible, the fabrication cost would go up, and the insertion of a card would become difficult.
With the connector which detects a card by the displacement of the switching terminal in the inserting direction of the card as shown in FIGS. 5A and 5B described above, moreover, in the case of a thinner card, the reaction force of the switching terminal would become larger so that the removing force for the card would not fulfil the removing force prescribed in the Standard of card, that is, normally more than 1N (98 g).

Card connector having card(s) detection capabilities


A substrate, such as, for example, a flap member of a pinch-bottom product bag, and a method of making the same, comprises a hot melt adhesive disposed upon the substrate so as to comprise first horizontally spaced upstanding portions whereby adhesive blocking is effectively eliminated or significantly reduced. A fiberized hot melt adhesive overcoat/overspray may also be disposed atop the hot melt adhesive to further assure the elimination or reduction in the adhesive blocking. The fiberized hot melt adhesive may also be used in conjunction with a conventionally applied hot melt adhesive base or foundation upon the substrate or deposited directly onto the substrate.

Pinch bottom bags comprise bags manufactured by a bag manufacturer wherein one end of the bag is initially sealed at the manufacturing plant while the other end of the bag is maintained open. Pinch bottom bags are commonly used as bags within which a particular product is to be filled by end-use customers to whom the bag manufacturer sells their pinch bottom bags. The open end of the bag has an adhesive-coated flap disposed thereon which is adapted to be heat-sealed to the body portion of the bag once the bag has been filled with product by the end-user customer. The pinch bottom bags are thus sold to customers who fill the bags with a specified product wherein the product is charged or filled into the bag, and upon completion of the filling of the bag with the desired amount of product, the flap of the pinch bottom bag, which was originally disposed at the open end of the pinch bottom bag, is then closed and sealed. Examples of uses for such pinch bottom product bags are those for containing dog food, granular chemicals, grass seed, bird seed, and the like. The flaps disposed at the open end of the pinch bottom bags are coated with an adhesive in a sufficient amount so as to permit the aforenoted closing and sealing of the product bag once the product bag has been completely filled. The open end flap is folded over onto the body portion of the bag, and a sufficient amount of heat is applied to the adhesive-coated flap so as to in fact bond the flap to the body portion of the bag. After the pinch bottom bags are manufactured by the bag manufacturer, the bags are loaded or stacked on pallets, compressed together in a face-to-back mode, strapped or otherwise secured together, and shipped to the bag manufacturer's end-use customers who will then fill the bag with their particular products. It has been noted, however, that even though the adhesive disposed upon the adhesive-coated flaps is effectively cool, or is at least at room temperature, the compression of the stack of bags, and the strapping or other-wise securing together of the bags, or the weight of multiple pallets stacked one on top of another, often causes the adhesive-coated flaps to stick together. In addition, the bags may encounter heated conditions during shipping or storage. In any case, this sticking together of the adhesive-coated flap members of the product bags is known in the industry as adhesive blocking and is a substantial problem for both the bag manufacturer and the end-use customer for several reasons. Firstly, due to such adhesive blocking, multiple bags become stuck together. The customer must then manually separate the bags which is both tedious and time-consuming. Customers may even file claims against the bag manufacturer for lost production time incurred as a result of necessarily separating the bags before the bags can be inserted into or mounted upon their automated product filling machinery or apparatus.
Secondly, sometimes, for example, two bags may remain stuck together despite the best efforts of the customer personnel to separate the bags. In addition, it is often the case that whether automated machinery or semi-automated machinery is being used, the stuck-together bags will go unnoticed by operator personnel due to the fact that they have multiple operating procedures to perform while the bags are being conveyed toward, inserted into, or mounted upon the bag filling machinery or apparatus. The real problem then is that such bag filling machines are not generally equipped to handle stuck-together bags. Accordingly, when the product bags are inserted within or otherwise mounted upon the customer's product filling machinery or apparatus, the machinery will not be able to properly open the bags in preparation for the product filling or charging operations. Therefore, product to be inserted, filled, or charged into the product bags is not in fact properly filled or charged into the bags, spillage of the product will occur, and therefore the machinery will need to be shut down in order to deal with such spillage occurrences. Such machinery shutdowns obviously cause lost production time and/or lost product, all of which may result in additional claims being made by the end-use customer against the bag manufacturer.
Thirdly, the end-use customer may simply choose to return all stuck-together bags to the bag manufacturer which of course results in additional charges and a waste of money for both the bag manufacturer and the end-use customer. The bag manufacturer obviously has to accept the returned bags in view of the fact that they are effectively defective products that cannot be used by the end-user customer filling machinery. The bag manufacturer then has several options, none of which are desirable from an efficient and profitable production point of view—(1) manufacturer personnel will have to sort every bag by hand in order to find the defective adhesively blocked bags; or (2) the manufacturer will have to effectively rework the bags; or (3) the manufacturer will have to re-manufacture the bags as new bags. Regardless of the option chosen, such bags effectively serve as lost production units. In addition, the end-use customer cannot use the adhesively-blocked bags which will retard the product-filling production lines, and in addition, must invest valuable manpower into packaging the stuck-together bags in preparation for return to the bag manufacturer. Still further, the bag manufacturer will probably have to absorb the transportation costs incurred for the bags being returned to the manufacturer by the end-user customer. Furthermore, the bag manufacturer may have additional sales or technical service expenses associated with attempts to resolve the problem prior to receiving the returned bags.
A need therefore exists in the art for a new and improved substrate, and a method for fabricating the same, wherein such adhesive blocking is effectively prevented such that the operational problems and difficulties associated with such adhesive blocking do not occur.

Anti-blocking adhesive-coated substrate, and a method for making the same


A nonleaded IC package, such as a QFN, including an encapsulation block having at least one generally flat lateral sidewall surface; and a plurality of leads, each terminating in a generally chair-shaped flat surface that is flush with the generally flat lateral sidewall surface.

Integrated circuit ("IC") packages typically include a leadframe, at least one die mounted on the leadframe and electrically connected to leads of the leadframe and a layer of encapsulating material covering part or all of the components. Leads of the leadframe are used to connect the die or other electronics within the IC package to outside circuit boards and other electronic components.
There are many different types of IC packages and the packages are categorized based upon various criteria. One criterion is the package lead configuration. Some IC packages have leads that project outwardly from one or more sides of the package encapsulation block. Other IC packages, so called nonleaded packages, have lead surfaces that are exposed but flush with one or more outer wall surfaces of the encapsulation block, i.e., these leads do not project beyond the encapsulation block outer surface. One popular type of nonleaded package is the quad flat no-lead package ("QFN"), which has lead surfaces exposed at the surface of the encapsulation layer on all four lateral sides and also at the bottom of the package.

Nonleaded package and leadframe strip and method


A more endearing robot includes an operation unit that causes the robot to operate, a viewing direction determiner that determines whether a viewing direction of a predetermined target is toward the robot or not, and an operation controller that controls the operation unit based on a result of determination by the viewing direction determiner.

Robots that communicate with humans are known. For example, Unexamined Japanese Patent Application Kokai Publication No. 2012-239557 discloses a robot that serves as a pet-like toy having a shape representing an animal. The robot disclosed in Unexamined Japanese Patent Application Kokai Publication No. 2012-239557 includes a liquid crystal display and a touch sensor at a position of the face. A petting operation on a face image displayed on the liquid crystal display varies the expression of the face image and causes a head and ears to sway from side to side.

More endearing robot, method of controlling the same, and non-transitory recording medium


This invention is advantageous in irradiating pallets which cannot be irradiated by conventional techniques, even by x-rays, throughout their complete volumes. In one embodiment, a scan horn scans electron beamlets through a sweep angle. A dipole bends the electron beamlets to focus the electron beamlets at the pallet center. After being bent, the beam becomes converted to x-rays which are irradiated through the pallet to the pallet center. During this irradiation, the pallet is moved in a direction substantially perpendicular to the irradiation. In this way, a quarter of the pallet is irradiated. When the quadrant radiation is completed, the radiation is interrupted and the pallet is rotated 90° to have a second side of the pallet face the radiation. The operation is sequentially repeated for each of the pallet sides. The four (4) irradiated quadrants define the pallet's complete cross-sectional area.

It has been known for some time that drugs and medical instruments and other implements have to be irradiated so that they will not cause patients to become ill from harmful bacteria when they are applied to the patients. Systems have accordingly been provided for irradiating drugs and medical instruments and other implements. The drugs and the medical instruments and other implements have then been stored in sterilized packages until they have been ready to be used.
In recent years, it has been discovered that foods can carry harmful bacteria if they are not processed properly or, even if they are processed properly, that the foods can harbor and foster the proliferation of such harmful bacteria if they are not stored properly or retained under proper environmental conditions such as temperature. Some of the harmful bacteria can even be deadly.
For example, harmful bacteria have been discovered in recent years in hamburgers prepared by one of the large hamburger chains. Such harmful bacteria have caused a number of purchasers of hamburgers at stores in the chain to become sick. As a result of this incident and several other similar incidents, it is now recommended that hamburgers should be cooked to a well done, or at least a medium, state rather than a medium rare or rare state. Similarly, harmful bacteria have been found to exist in many chickens that are sold to the public. As a result of a number of incidents which have recently occurred, it is now recommended that all chickens should be cooked until no blood is visible in the cooked chickens.
To prevent incidents such as discussed in the previous paragraphs from occurring, various industries have now started to irradiate foods before the foods are sold to the public. This is true, for example, of hamburgers and chickens. It is also true of fruits, particularly fruits which are imported into the United States from foreign countries. The fruit is irradiated to disinfect the fruit and rid the fruit of insects and fleas.
In previous years, gamma rays have generally been the preferred medium for irradiating various articles. The gamma rays have been obtained from a suitable material such as cobalt and have been directed to the articles to be irradiated. The use of gamma rays has had certain disadvantages. One disadvantage is that irradiation by gamma rays is slow. Another disadvantage is that irradiation by gamma rays is not precise. This results in part from the fact that the strength of the source (e.g. cobalt) of the gamma rays decreases over a period of time and that the gamma rays cannot be directed in a sharp beam to the articles to be irradiated. This prevents all of the gamma rays from being useful in irradiating the articles.
In recent years, electron beams have been directed to articles to irradiate the articles. Electron beams have certain advantages over the use of gamma rays to irradiate articles. One advantage is that irradiation by electron beams is fast. For example, a hamburger patty having a square cross section can be instantaneously irradiated by a passage of an electron beam of a particular intensity through the hamburger patty. Another advantage is that irradiation by an electron beam is relatively precise because the strength of the electron beam remains substantially constant even when the electron beam continues to be generated over a long period of time. A further advantage is that the space occupied by the electrons and the direction of movement of the electrons can be precisely controlled since the electrons are in the form of a beam. A disadvantage is that the electrons can penetrate an article through only a limited distance. To increase the distance of penetration of the article, the electron beams can be directed to opposite sides of the article.
X-rays have also been used to irradiate articles. The x-rays may be formed from electron beams. An advantage in irradiating articles with x-rays is that the x-rays can irradiate articles which are thicker than the articles which are irradiated by electron beams. However, it would also be desirable to irradiate articles with x-rays from opposite sides of the articles to enhance the uniformity of the absorbed x-ray energy within the articles and to enhance the efficiency with which the x-ray energy is absorbed by the articles. Application Ser. No. 10/224,062 filed by me on Aug. 20, 2002 for a System For and Method of Irradiating Opposite Sides of an Article and assigned of record to the assignee of record of this application discloses and claims a system for irradiating articles with x-rays at opposite sides of the article by using only a single source of irradiation.
By using a single source of x-rays to irradiate opposite sides of the article, the radiant energy at the opposite sides of the article are substantially identical so that each of the opposite sides of the article receives substantially identical patterns of radiation. Furthermore, the costs are minimized since accelerators are quite expensive.
Sometimes the articles to be irradiated are so thick that the central portion of the article cannot be properly irradiated even when the articles are irradiated with x-rays from opposite sides of the articles. For example, this is true of dense food stuffs. In such instances, the minimum required dose cannot be provided at the center of the pallet without overdosing the outer regions of the pallet.


A system and method for injection molding conductive bonding material into a plurality of cavities in a non-rectangular mold is disclosed. The method comprises aligning a fill head with a non-rectangular mold. The non-rectangular mold includes a plurality of cavities. The fill head is placed in substantial contact with the non-rectangular mold. Rotational motion is provided to at least one of the non-rectangular mold and the fill head while the fill head is in substantial contact with the non-rectangular mold. Conductive bonding material is forced out of the fill head toward the non-rectangular mold. The conductive bonding material is provided into at least one cavity of the plurality of cavities contemporaneous with the at least one cavity being in proximity to the fill head.

In modern semiconductor devices, the ever increasing device density and decreasing device dimensions demand more stringent requirements in the packaging or interconnecting techniques of such devices. Conventionally, a flip-chip attachment method has been used in the packaging of IC chips. In the flip-chip attachment method, instead of attaching an IC die to a lead frame in a package, an array of solder balls is formed on the surface of the die. One process for forming solder balls is carried out by an evaporation method of lead and tin through a mask for producing the desired solder balls.
One problem with through-mask evaporation is that material is used very inefficiently. The efficiency of material use is becoming increasingly important as recent materials requirements such as ultra-low alpha lead and Pb-free drive have increased material costs. Another problem with through-mask evaporation is that when the bump pitch falls below 225 μm, yields begin to degrade with evaporation. Additionally, longer evaporation times are required with Pb-free solders. Yet a further problem with evaporation methods is that 300-mm evaporation masks used for 300-mm wafers are not very stable or robust.
Other solder ball formation techniques that are capable of solder-bumping a variety of substrates have also been proposed such as solder plating and solder paste screening. In solder plating a layer of solder is applied directly to a conductive pattern. The solder coating can be used as an etch mask. These techniques work fairly well in bumping semiconductor substrates that contain solder structures over a minimum size. One of the more popularly used techniques is a solder paste screening technique which can be used to cover the entire area of an 8 inch wafer. However, with the recent trend in the miniaturization of device dimensions and the reduction in bump-to-bump spacing (or pitch), the solder paste screening technique becomes impractical. For instance, one of the problems in applying solder paste screening technique to modern IC devices is the paste composition itself. Pastes are generally composed of a flux and solder alloy particles. The consistency and uniformity of the solder paste composition become more difficult to control with a decreasing solder bump volume.
A possible solution for this problem is the utilization of solder pastes that contain extremely small and uniform solder particles. However, this can only be done at a high cost penalty. Another problem in using the solder paste screening technique in modern high density devices is the reduced pitch between bumps. Since there is a large reduction in volume from a screened paste to the resulting solder bump, the screen holes must be significantly larger in diameter than the final bumps. The stringent dimensional control of the bumps makes the solder paste screening technique impractical for applications in high density devices.
A more recently developed injection molded solder ("IMS") technique attempted to solve these problems by dispensing molten solder instead of solder paste. However, problems have been observed when the technique is implemented to wafer shaped substrates. U.S. Pat. No. 5,244,143, which is commonly owned by International Business Machines Corporation, discloses the injection molded solder technique and is hereby incorporated by reference in its entirety. One of the advantages of the IMS technique is that there is very little volume change between the molten solder and the resulting solder bump. The IMS technique utilizes a solder head that fills molds of various materials such as boro-silicate glass, silicon, polymers, metals, and the like that are wide enough to cover most single chip modules. Excess solder is removed as the solder head moves about the mold. The IMS method for solder bonding is then carried out by applying a molten solder to a substrate in a transfer process. When smaller substrates, i.e., chip scale or single chip modules are encountered, the transfer step is readily accomplished since the solder-filled mold and substrate are relatively small in area and thus can be easily aligned and joined in a number of configurations. For instance, the process of split-optic alignment is frequently used in joining chips to substrates. The same process may also be used to join a chip-scale IMS mold to a substrate (chip) which will be bumped. One problem with current IMS systems is that they have been restricted to linear deposition of solder into rectangular molds. That is, the mold and the solder head are moved linearly with respect to each other such that the cavities move perpendicular to a slit in the solder head thereby filling the cavities as they pass. The molds are limited to a rectangular configuration.
Therefore a need exists to overcome the problems with the prior art as discussed above.

Rotational fill techniques for injection molding of solder


The invention relates to a method and an apparatus for measuring the properties of paper from a moving paper web in a paper machine. An infrared beam is directed to the paper web. The infrared beam, passed through or reflected from the paper web, is split into wavelength components with a spectrograph, and signals of the different wavelength components are measured, and the properties of paper are determined on the basis of the signals.

The invention relates to methods and apparatus of measuring the properties of paper from a moving paper web in a paper machine, in which measurement is carried out in the infrared region, most preferably in the wavelength range of 1 to 10 xcexcm.
U.S. Pat. No. 4,733,078 discloses an apparatus which directs a radiation beam to a target through a rotating filter wheel driven by a motor, the filters in the filter wheel emitting only a given wavelength of light at a time to the target. The light that has passed through the paper is detected at different wavelengths and the desired content of the substance is determined from the target on the basis of signals thus obtained. The problem in measuring a moving target is that the measurements of different wavelength channels are successive, since each filter illuminates a different point in the target. Before the following filter has had time to revolve in front of the light source, the target to be measured has slightly moved to a different point, and consequently the penetration point is not quite the same. In this case the proportional measurement, based on a reference wavelength, does not remove the gray factor variation caused by scattering, resulting in a significant error in measurements of non-homogenous, moving material, such as paper.
U.S. Pat. No. 3,641,349 discloses an apparatus in which a light beam, having passed through the paper sheet, is split into several parts. Each different part of the beam is detected by a separate detector, in front of which are disposed narrow-band filters, the signals being measured in parallel. Parallel measurement eliminates measuring noise caused by a non-homogenous moving target, but the number of channels is limited in this solution. The solution becomes cumbersome in applications requiring more than four channels, and its optical efficiency declines as the number of channels increases. Furthermore, because of the filters, resolution and central wavelength tolerances are quite bad, complicating the transfer of calibration from one device to another. The filters used also make it difficult to reach a sufficiently narrow band for the right wavelength, e.g. for measuring kaolin. Still further, lead sulphide detectors are extremely dependent on temperature, a different temperature in detectors disposed at different points causing significant errors in measurement.
WO 96/42010 discloses an apparatus for measuring the color and color-related properties of a moving web by reflectance measurements. This color measurement utilizes a black and white background behind the web, the reflected light beams being measured by two different sensors. The sensor uses a spectrograph which distributes the light beam to the detectors. The measured signals are transmitted serially from the detectors to a computer for further processing. However, serial processing is not always sufficiently efficient. Moreover, the solution of the publication cannot be utilized in applications in which the properties of paper are to be measured in the infrared region.
It is an object of the present invention to provide a method and an apparatus which avoid the above drawbacks.
The method of the invention is characterized by directing to the paper web an infrared beam modulated by a chopper, splitting the infrared beam which has passed through the paper web or reflected therefrom by a spectrograph into different wavelength components, measuring signals corresponding to the different wavelengths in parallel, detecting the signals using parallel detection synchronized to the chopper, and processing the signal in parallel and determining the properties of the paper on the basis of the wavelength components determined by the spectrograph.
The apparatus of the invention is characterized by comprising a radiation source for producing an infrared beam, a chopper for modulating the infrared beam, a spectrograph for splitting the infrared beam reflected from or passed through the paper web into different wavelength components, means synchronized to the chopper for parallel detection and processing of the wavelength components, and means for determining the properties of the paper on the basis of the different wavelength components split by the spectrograph.
An essential idea of the invention is to measure the properties of a moving paper web by directing an infrared beam modulated by a chopper to the paper, and splitting the beam which has passed through or reflected from the paper into different wavelengths by means of a spectrograph, measuring signals corresponding to the different wavelengths, detecting the signals using parallel detection synchronized to the chopper, and processing the signal in parallel. It is the idea of a preferred embodiment to split a light beam optically by a spectrograph into different wavelengths and to measure the signals of the different wavelengths from the spectrograph with separate detectors. The idea of another preferred embodiment is that the detectors employed are array detectors.
It is an advantage of the invention that because all measuring channels and reference channels are measured exactly simultaneously, the desired statistical accuracy is promptly reached when a non-homogenous rapidly moving sample is measured. Furthermore, detecting and processing the beam in parallel and continuously allows a narrow electric pass band for detector electronics, improving the signal to noise ratio of the detection and making the detection more immune to ambient light interference. Furthermore, measuring time can be utilized to a hundred percent for each channel, which also improves the signal to noise ratio of the detection. A spectrograph provides a high number of channels, good resolution, low central wavelength tolerances and repeatability of the wavelength scale from one device to another. The solution is also applicable to different numbers of wavelengths and to measurements of a continuous spectrum. A high number of wavelengths allows the effect of a change in sample temperature on the measurement to be compensated for, accurate measurements of binders, measurements of different binders, better immunity to interfering components and widening of the basis weight region of the paper to be measured by the use of different wavelength in different applications. In a device with a better wavelength resolution, reference channels can be brought nearer the measuring channel, resulting in e.g. better immunity to baseline bend. In an array detector the detector elements are in the same hermetic casing and of the same production lot, allowing a better immunity to be achieved to changes in ambient temperature than when several separate detectors are used.
In the present application, in addition to paper, the term xe2x80x9cpaperxe2x80x9d also refers to paperboard.

Method and apparatus for measuring properties of paper


The present invention provides a power efficient content-addressable memory (CAM) architecture that is implementable on FPGAs. The provided CAM architecture comprises an array of CAM cells having a width CW and a depth CD, and being grouped into a B number of memory banks. Each of the CAM cells is configured for storing a memory bit and comprises a plurality of flip-flops configured to store at least a masking bit indicating the ternary nature of the stored memory bit and a storing bit saving the binary information of the stored memory bit. The provided CAM architecture allows activating only one bank in multiple banks irrespective of nature of the data set and is updated in a single access and saves power consumption by only accessing the memory in the activated bank. The dynamic power consumption is reduced by 40% compared with the state-of-the-art FPGA-based CAMs.

CAM is specialized hardware that accelerates the parallel searching of large lookup tables for data-intensive applications. In networking, packet classification and forwarding are achieved using a ternary CAM (TCAM) that stores wild cards ("don't care" bits) and results in a match for every search operation. A binary CAM (BiCAM) can only handle "1" and "0" but not wild cards. Both BiCAM and TCAM have different applications, including access control lists, routing tables, and translation lookaside buffers (TLBs).
Recent developments in art are advancing toward software-defined networking (SDN), which requires flexible, reconfigurable, and high-performance hardware for its implementation. Compared to ASIC-based CAMs, which are less reconfigurable, expensive, and challenging to integrate, FPGAs are the most pertinent platforms to implement SDNs where it needs a software-defined (i.e., FPGA-based) CAM, instead of hard-wired (i.e., ASIC-based) CAM.
FPGA-based CAMs are becoming popular due to the aforementioned capabilities. However, most of the existing architectures activate the whole hardware for each search operation, thus have high latency and power consumption. For examples, Xilinx presents two CAM architectures in an application note [1]. A TCAM design based on LUTRAM presented in [2] requires 64 clock cycles to update a single entry in TCAM. A hierarchical CAM design presented in [3] divides the storing memory into low and high priority blocks. A fast-updating architecture presented in [4] updates a single rule in BRAM-based TCAM in which the worst-case latency remains high and is equal to the depth of BRAM in modern FPGAs, i.e., 512. Therefore, there is an unmet need in the art for a power-efficient CAM design on existing FPGA architectures.

Bank-selective power efficient content-addressable memory