In the recording apparatus 121, a recording medium fixing member 123 having a plurality of suction ports on the fixed surface to fix the recording medium 101; an adhering roller 143 which can contact with or separate from the recording medium fixing member 123 and which cleans the fixed surface; a flexible plate 137 which is attached onto the fixed surface of the recording medium fixing member 123 and whose contact surface with the recording medium is cleaned by the adhering roller 143; and a suction apparatus for recording medium fixing which sucks the air from the suction ports of the recording medium fixing member 123 and sucks and fixes the flexible plate 137 and the recording medium 101 onto the fixed surface of the recording medium fixing member 123, are provided.

1. Field of the Invention
The present invention relates to a recording apparatus to produce an image on a recording medium being attached onto a recording medium fixing member, more specifically an adhered foreign material removal method or device therefor, and further a method to prevent the position dislocation, separation and film peeling of the recording medium due to the cleaning motion.
2. Description of the Related Art
In the recording of an image or character, there is a recording method by which an image receiving sheet which is a recording medium, and a transfer sheet which is a recording medium in the same manner, are superimposed and fixed on the recording medium fixing member(drum) and exposed by the laser. In this recording medium, one kind of image receiving sheet and a plurality of kinds of transfer sheets such as K (black), C (cyan), M (magenta), Y (yellow), are used. These recording media are set in a cassette for a recording medium of the recording apparatus in a reversal order to the recording order. Accordingly, in the cassette, from the upper layer, the image receiving sheet, and a plurality of recording media in the order of K, C, M, Y, are set in the laminated condition. In this connection, when a plurality of sets of the recording medium are set, these operations are repeated and the recording media are set.
In such the manner, a cassette 103 in which the recording media 101 are accommodated in recording order, is installed in a recording apparatus 105 as shown in FIG. 2. A pickup mechanism 107 is provided in the recording apparatus 105, and the pickup mechanism 107 has a function by which only one sheet of the recording medium 101 of the uppermost layer is picked up from the inside of the cassette 103 by, for example, rubber roller or suction absorption mechanism. By this pickup mechanism 107, after the recording medium 101 whose only one sheet is picked up passes through a conveying mechanism in which a guide plate, not shown, or roller is used, it is fixed on a drum 109 for recording.
As shown in FIG. 3, in the recording apparatus 105, a recording head 111 to conduct, for example, the laser exposure is provided, and the recording head 111 is reciprocally moved in a parallel direction to the rotation axis of the drum 109. The laser light Lb is emitted from the recording head 111, and irradiated as a plurality of spots. In this recording method, the rotation direction of the drum 109 is a main scanning direction, and the movement direction of the recording head 111 is a sub scanning direction. Accordingly, when the rotation movement of the drum 109 and the linear movement of the recording head 111 are combined, the spot scans on the transfer sheet, and a desired image is transferred onto the image receiving sheet.
When the recording apparatus 105 is operated, initially, the image receiving sheet is supplied and conveyed to the drum 109. At this time, the image receiving layer of the image receiving sheet is fixed so as to face the outside of the drum 109. Next, the recording apparatus 105 supplies and conveys a K color transfer sheet onto the image receiving sheet on the drum 109. In this case, the toner layer of the transfer sheet is fixed so as to face the image receiving layer of the image receiving sheet. That is, the image receiving layer of the image receiving sheet and the toner layer of the transfer sheet are superimposed. Next, the recording apparatus 105 records on the recording medium 101 fixed on the drum 109 by the recording head 111. After the recording by the K-color data is completed, only the K-color transfer sheet is peeled off from the drum 109, and delivered to the outside of the recording apparatus 105. When these supplying, recording, and delivering operations are conducted for the C, M, Y-color transfer sheets in the same manner, a desired color image is transferred onto the image receiving sheet.
In this connection, onto the drum of the recording apparatus described above, in order to avoid the image defects due to undulations of the drum surface (cutting flaw at the time of drum processing, cutting streak, groove or hole of the recording medium fixing release mechanism), or to enable to cope with each kind of sizes of recording medium, there is a case where a flexible plate (plate) is attached. In such the recording apparatus, the recording defects due to the adherence of the foreign material onto the flexible plate becomes a problem. The recording defects due to the adherence of the foreign material are largely divided into two kinds. One is the recording defect (generation of so-called [image reversing]) in the case where the foreign material on the flexible plate is adhered onto the image receiving sheet. Another one is the recording defect (generation of so-called [ring unevenness]) in the case where the foreign material is adhered onto the flexible plate.
The image reversing is generated due to the generation of the poor close contact of the transfer sheet with the image receiving sheet by the foreign material when the foreign material exists on the image receiving sheet. Further, the ring unevenness is generated when the foreign material exists on the flexible plate. That is, in the central portion in which the foreign material exists, although the transfer sheet and the image receiving sheet are closely contacted with each other, in its periphery, a gap is formed ring-like between the transfer sheet and the image receiving sheet, therefore, the transferring can not be performed in this gap, and the white un-transferred portion is generated ring-like around the foreign material. Further, due to the foreign material adhered on the flexible plate, the position dislocation is generated in the perpendicular direction to the rotation axis of the drum, and the focal point of the laser light for recording is shifted, and the sufficient energy density can not be obtained, and there is a case where the thinning of the image or lowering of the density is generated, and the image unevenness is generated.
Further, in the conventional apparatus, as described above, although the foreign material adhered onto the recording medium during the apparatus operation can be removed, the foreign material adhered and piled onto the recording medium conveying means such as the rotating drum for the recording or nip roller in the condition that the recording medium is not conveyed such as the case where the apparatus is not used, can not be removed. Therefore, specifically, the foreign material is adhered onto the image receiving sheet conveyed just after the power supply of the apparatus is turned on, and the image defect is generated.
Next, after these recording media are supplied to a supply tray, the uppermost one sheet is taken out by a pick-up roller, and conveyed to the rotating drum for the recording position by a conveying roller (nip roller) arranged on an intermediate route of a conveying path, and wound around the drum surface and fixed. In this manner, on the recording medium conveying path in the recording apparatus, several conveying rollers are arranged, and by these conveying rollers, the recording medium is conveyed at a predetermined timing.
In these conveying rollers, when any one roller is an adhesive roller, there is a case where the conveyance and cleaning effects are provided together, or a cleaning roller (formed of the adhesive roller) for the purpose of foreign material removal is provided separately from the conveying roller. When the adhesive roller is provided, the removal of the foreign material adhered onto the recording material and removal of the foreign material adhered during the recording medium conveyance can be conducted. Further, when the cleaning roller is arranged so that it can come into contact with the rotating drum for the recording, the removal of the foreign material adhered onto the rotating drum for the recording, and the removal of the foreign material adhered onto the recording medium during the supply and conveyance of the recording medium to the rotating drum for the recording, or the removal of the foreign material adhered onto the recording medium during the delivery conveyance of the recording medium from the rotating drum for the recording, can be conducted.
For the pick-up roller, conveying roller, and cleaning roller used in the conventional recording apparatus, generally, a roller of straight shape in which the diameter of the roller is constant along the whole width direction, is used. In this roller of straight shape, when the roller is brought into contact with the other material by only self weight of the roller, the contact can be evenly conducted along the whole width direction of the roller, however, when, as the nip roller 370 shown in FIG. 35(a), it structures the roller pair, and nips with a predetermined pressing force between each of rollers, because the roller is bent, there is a tendency that the pressing force at the central portion in the width direction of the roller is smaller, and in the worst condition, there is a case that the pressing force at the central portion can not be obtained. Further, even when the nip roller is not structured, as shown in FIG. 35(b), for example, a drive mechanism 372 such as air piston is provided on both ends of the roller, and the roller 374 can be pressed onto the opposite surface. In the same manner also in this case, there is a tendency that the pressing force at the central portion in the width direction becomes small by the bend generated in the roller 374.
In this connection, the recording medium conveyed in the recording apparatus makes, when it is wound around the rotating drum for the recording and fixed, the image receiving sheet and the color material sheet superimposed, and closely contacted with each other by the vacuum suction or pressure roller. In the degree of the close contact, it is large at the edge portion of the sheet, and at almost the central portion of the sheet, because the air flow resistance becomes large, the suction easily becomes insufficient, and there is a case where the close contact is not conducted sufficiently. In this condition, when the foreign material exists on the sheet, the image defect due to the foreign material is particularly easily conspicuous at the central portion in the width direction. Therefore, it is necessary that the foreign material removal at the central portion in the width direction is assuredly conducted.
Accordingly, when the recording medium is pressed by the pressure roller (for example, a laminate roller, cleaning roller, squeeze roller) which can be brought into contact with the surface of the rotating roller for the recording, from the above reason, the pressing force at the central portion in the width direction of the roller becomes weak, and there is a problem that the degree of the close contact of the recording medium is lowered.
Further, when the material used for the adhesive roller is an adhesive rubber material or adhesive substance, because there is a case where the adhesive strength is lowered by the natural aging, therefore, after the production of the adhesive roller, the adhesive strength is lowered after about 302-303 months, and the ability to remove the foreign material on the recording medium is lowered. As the result, there is a problem that a portion on which a desired image is not recorded is generated on the recording image, and the image defect is generated.
In the related cleaning method of the recording medium, one end portion of the recording medium set on the rotating drum for the recording is a cleaning start point, and the other end portion is a cleaning end point, and a cleaning roller is brought into contact with the recording medium and the cleaning is continuously conducted. In FIG. 43, the conventional cleaning procedure is shown. As shown in FIG. 43(a), when a cleaning roller 450 is brought into contact with the end portion 1a of the recording medium or the drum surface on this side of the end portion 1a, and the rotating drum for the recording 412 is rotated, at the end portion 1a of the recording medium, because there is a tendency that the suction force to the rotating drum for the recording 412 is lowered, the adhesive strength of the cleaning roller 450 is sometimes relatively larger than the vacuum suction force from the rotating drum for the recording 412. In this case, as shown in FIG. 43(b), the end portion 1a of the recording medium 401 is wound around the cleaning roller 450. Further, in the same manner, when the cleaning roller 450 which is brought into contact with the recording medium 401 is vertically separated from the recording medium 401 at the end portion 1a, there is a possibility that the recording medium 401 is pulled up and a portion of the end portion 1a is separated from the rotating drum for the recording 412, or the film of the recording medium 401 is peeled off.
Therefore, the adhesive strength of the cleaning roller 450 is previously appropriately designed corresponding to the characteristic of the recording medium 401, and when it is necessary that the applicable kind of the recording medium 401 is enlarged or the foreign material is removed more strongly, there is sometimes a case in which the cleaning roller formed of the material having the strong adhesive strength is used, or the rubber roller whose rubber hardness is small and whose flexibility is high is used. In this case, because the adhesion property of the cleaning roller 450 is strong, problems in which the position dislocation is generated in the recording medium 401 on the rotating drum for the recording 412, or the suction leakage for the recording medium fixing is increased by this position dislocation, and the recording medium 401 is separated from the rotating drum for the recording 412, or the film (the image receiving layer 2c of the image receiving sheet 402 or cushion layer 2b) of the recording medium 401 is peeled off, are generated.
Further, as a conveying mechanism of the sheets used for the above related arts, there is a mechanism in which the image receiving sheet or transfer sheet is previously cut into a predetermined dimensions, and the image receiving sheet and the transfer sheet of a plurality of colors (or single color) are accommodated in a cassette of the recording apparatus, and at the time of recording, these sheets are successively conveyed, or on the one hand, a mechanism in which a roll for the image receiving sheet and a plurality of rolls corresponding to the plurality of colors of the transfer sheet are provided in the recording apparatus, and at the time of recording, these sheets are cut into predetermined dimensions by respective rolls, and conveyed to the rotating drum for the recording.
The image receiving sheet conveyed by the above mechanism, after it is wound around the rotating drum for the recording with the image receiving surface facing upward and fixed, the transfer sheet is conveyed to the rotating drum for the recording and the toner layer of the transfer sheet is superimposed on the image receiving layer of the image receiving sheet, and wound around the rotating drum for the recording. In this manner, onto the image receiving sheet and the transfer sheet which are superimposed on each other on the rotating drum for the recording, the laser exposure is conducted by the recording head. In the recording by the laser exposure, the recording and transferring is conducted when the rotating drum for the recording is rotated in the circumference direction of the drum, and the recording head is reciprocally moved in the rotating axis direction of the rotating drum for the recording. Then, the transfer sheet onto which the first transfer is conducted, is peeled off from the image receiving sheet, and after it is delivered, the next transfer sheet is conveyed in such a manner that it is superimposed on the image receiving sheet on the rotating drum for the recording, and fixed, and after that, it is transferred onto the image receiving sheet. After the transfer process onto the image receiving sheet is conducted for a plurality of times (a plurality of colors), when the image receiving sheet onto which the transfer is conducted, is transferred onto the another sheet, a desired color recording is conducted.
In this connection, there is sometimes a case in which the foreign material such as dirt or dust is adhered onto the surface of the recording medium supply section, recording medium conveying section, recording section in the recording apparatus, or recording medium during conveying by the static electrical force, and when recording is conducted without removing these foreign material, it becomes a cause by which the image defect such as the [image reversing] due to the existence of the foreign material between the image receiving sheet and the transfer sheet, or the [ring unevenness] due to the mixing of the foreign material between the drum for the recording and the image receiving sheet or between the transfer sheet and the roller, is caused. Therefore, the adhesive roller (cleaning roller) using the adhesive rubber is arranged in order to remove the foreign material adhered onto the surface of the conveying path of the recording material or recording section in the recording apparatus, and the adhesive roller is pressed on the surface which is the object of the foreign material removal, periodically or in need, and the foreign material is removed, and the system is made so that the good recording condition is always maintained.
However, recently, there is a system in which the pressing of the adhesive roller onto the surface which is the object of the foreign material removal is conducted by a movement apparatus such as an air cylinder, and at the time of requirement or periodically, the adhesive roller is automatically moved onto the objective surface of the foreign material removal, and the foreign material of the surface is removed. However, in the adhesive roller provided with the movement mechanism, the control of the pressing force onto the foreign material removal surface, that is, the minute amount control of the movement amount of the movement mechanism is difficult, and there is a case in which a poor foreign material removal due to insufficient pressing force onto the foreign material removal surface is generated, or the position dislocation of the image receiving sheet or transfer sheet fixed onto the rotating drum for the recording due to the increase of the adhesive strength by the excessive pressing force is generated. Further, due to the excess of the pressing force onto the sheet surface of the adhesive roller, the adherence peeling of the surface layer such as the image receiving layer of the image receiving sheet or cushion layer, or the adherence peeling of the surface layer such as the color material layer of the transfer sheet or photo thermal conversion layer is frequently generated. Then, every time when the poor recording due to the adherence peeling of the image receiving sheet or transfer sheet is generated, it is necessary that the recording apparatus is stopped, and the operation such as the taking out of the poor sheet or the reset of the image receiving sheet or transfer sheet is conducted, thereby, the transfer recording efficiency of the recording apparatus is not always good, and the improvement of the foreign material removal mechanism using the adhesive roller is required.

Recording apparatus and method of foreign material removal thereof


Various embodiments provide for tag-based application of a masking policy, which can be used in connection with a data platform. In particular, various embodiments enable enforcement of one or more masking policies against an entity (e.g., object) of a data platform, such as a database, a table, a row, or a column, based on one or more tags associated with the entity.

Databases are widely used for data storage and access in computing applications. A goal of database storage is to provide enormous sums of information in an organized manner so that it can be accessed, managed, updated, and shared. In a database, data may be organized into rows, columns, and tables. Databases are used by various entities and companies for storing information that may need to be accessed or analyzed. To protect certain types of data, such as personally identifiable information (PII) (e.g., email, phone number, name, gender, birth date, home address, Internet Protocol (IP) address, social security number, or the like) or finance data, a system can apply a policy (e.g., at database, a table, a column, or row level) to mask data as it is accessed.

This patent is subject to a terminal disclaimer.


A pre-expanded polypropylene resin particle can be produced in the following manner: a polypropylene resin particle produced by an under water cut method, water, a dispersing agent, and a foaming agent are charged in a pressure-resistant container, the resulting mixture is heated to a temperature equal to or higher than the softening temperature of the polypropylene resin particle to allow the polypropylene resin particle to be impregnated with the foaming agent under pressure, and the resulting product is released into the atmosphere having a pressure lower than the pressure of the inside of the pressure-resistant container. As the polypropylene resin composition, a composition is used which comprises 100 parts by weight of a polypropylene resin and 1 to 20 parts by weight of a polyethylene resin having a melt viscosity of 10 to 2000 mPa·s at 140° C., whereby it becomes possible to reduce the pressure of a heated molding vapor required for producing an in-mold expanded molding product having a fusion rate of 75% or higher.

In-mold expansion-molded articles prepared by using pre-expanded polypropylene resin particles are characteristic in their freedom in designing the shape, lightness and heat insulation efficiency, i.e., advantages of in-mold expansion-molded articles. When compared with similar in-mold expansion-molded article, they are superior in chemical resistance, heat resistance and distortion recovery rate after compression, compared with in-mold expansion-molded articles prepared by using pre-expanded polystyrene resin particles and also superior in dimensional accuracy, heat resistance and compression strength, compared with in-mold expansion-molded articles prepared by using pre-expanded polyethylene resin particles. Due to these characteristics, the in-mold expansion-molded articles prepared by using pre-expanded polypropylene resin particles have been used as automobile interior parts, core materials for automobile bumpers, and also in various applications such as heat insulators and buffering packaging materials.
Polypropylene resin particles are prepared, for example, by strand-cutting method or underwater cutting method. It is possible to produce uniform resin particles in cylindrical shape with a relatively inexpensive equipment by the strand-cutting method, but production of fine polypropylene resin particles of 2 mg/particle or less in weight by the method resulted in frequent miscutting and breakage of the strands, leading to deterioration in productivity. In addition, there was a problem of relatively low productivity and others, because there is a limit in increasing the number of strands.
It is known that it is easy to initiate granulation and possible to produce uniform-sized polypropylene resin particles at high productivity with less miscutting by the underwater cutting method, because the strand needs not be withdrawn.
Patent Document 1 describes a problem in the method of producing polypropylene resin particles for pre-expanded polypropylene resin particles by the underwater cutting method that the fusion rate of the pre-expanded polypropylene resin particles during in-mold expansion molding is not favorable, and discloses a method of extruding a resin into high-temperature circulating water and cutting the extruded resin in the water, as a countermeasure. However, it is needed to add slightly water-soluble inorganic materials, surfactants and antifoams to the circulating water for prevention of agglomeration, and it is necessary to add the ingredients above consistently for preservation of the concentrations of the additives in the circulating water, which may lead to water pollution.
Patent Document 2 discloses pre-expanded particles prepared from a resin mixture containing 55 to 95 wt % α-olefin-propylene copolymer having a flexural rigidity of 7000 to 14000 kg/cm2 and 5 to 45 wt % linear polyethylene resin having a density of 0.88 to 0.94 g/cm3 as base resin, for the purpose of providing an in-mold expansion-molded polyolefin resin article superior in buffering property, impact resistance and heat resistance. However, the Patent Document does not describe anything about the problem that the fusion rate of the pre-expanded particles prepared by the underwater cutting method is unfavorable.
Patent Document 3 discloses that expanded resin particles having a core layer of a crystalline thermoplastic resin in the expanded state and a sheath layer of an ethylenic polymer having a melting point lower than the thermoplastic resin in the non-expanded state have favorable fusion rate even at low heating steam pressure. However, the method demands a large-scale production equipment, because two extruders are needed.    Patent Document 1: JP-A No. 10-119037    Patent Document 2: JP-A No. 4-253741    Patent Document 3: JP-A No. 10-77359

Pre-expanded polypropylene resin particle, and method for production thereof


A pneumatic actuator includes a cylinder, an output shaft disposed rotatably in the cylinder, a pinion disposed in the output shaft, a piston rod furnished with rack teeth to be meshed with the pinion, and pistons disposed one each at opposite ends of the piston rod, wherein the pneumatic actuator further includes a pressure-inspecting chamber enclosed with the cylinder and the piston and a pressure-detecting hole establishing communication between the pressure inspecting chamber and the exterior.

1. Technical Field
This invention relates to a pneumatic actuator for rotating an output shaft by transforming a linear motion (reciprocating motion) generated by compressed air into a rotary motion. More particularly, this invention relates to a pneumatic actuator to be applied to a ball valve, a butterfly valve or other similar valve that switches a valve body, such as a ball or a disk, by a rotation of about 90°.
2. Description of the Related Art
The conventional pneumatic actuator for use in the valve has adopted such a structure as to impart a switching motion to the valve body of a rotary valve, such as a ball valve or a butterfly valve, by converting a linear motion (reciprocating motion) into a rotary motion through a built-in motion-transforming mechanism and causing the turning force produced in an output shaft in consequence of the transformation effected by the aforementioned motion-transforming mechanism to a stem connected to the output shaft. The motion-transforming mechanism that is built in this actuator is known in the scotch yoke type and the rack-and-pinion type. Particularly, most actuators of small sizes adopt the rack-and-pinion type motion-transforming mechanisms.
Incidentally, the rack-and-pinion type motion-transforming mechanisms generally have a structure comprising a rotatably disposed output shaft furnished in a cylinder with a pinion, a pair of pistons disposed in the cylinder and adapted to produce a reciprocating motion therein, and racks fitted each to the pistons so that the reciprocating motion of the pistons may be transformed into a rotary motion by virtue of the mesh to be formed between the racks and the pinion.
In the rack-and-pinion type pneumatic actuators mentioned above, the inclinations of the pistons during the operation thereof are ordinarily regulated on the basis of the effective diameters of the pinions and the racks of the pistons by the sliding surfaces occurring between the outside diameters of the pistons and the inside diameter of the cylinder and particularly the pistons themselves during their reciprocating motions tend to produce a phenomenon of inclining in the axial or rotary direction thereof. These actuators, therefore, have entailed the problem of suffering the pistons to sustain fracture and scouring their surfaces even to an extent of degrading their output efficiency.
The following techniques have been heretofore proposed as measures to cope with these problems. JP-A-SHO 53-103915 (hereinafter referred to as "Patent Document 1") discloses a structure which, with the object of coping with the problem, precludes the phenomenon of the inclination of the pistons during the reciprocating motion thereof by having pistons provided one each at the opposite terminals of a piston rod furnished with rack teeth to be meshed with a pinion and causing an annular body fixed with a key to the shaft to be brought into rolling contact with a travel route fastened to the supporting parts of the rack teeth.
Utility Model Registration No. 2561362 (hereinafter referred to as "Patent Document 2") teaches an actuator that is provided along the longitudinal direction of a rack surface with a guide rail and has this guide rail disposed so as to be freely guided on the outer peripheral surface of an output shaft.
The prior art references mentioned above concern techniques that, in actuators adapted to switch a valve with compressed air and a compression spring respectively as a power source, make it possible to alleviate the phenomenon of the inclination of the pistons used therein toward the axial directions and the rotary directions thereof. The technique disclosed in Patent Document 1 requires an annular part for contact with the rack. When the actuator is in such a structure as to induce deviation of the output shaft from the center of the cylinder, the annular body mentioned above is inevitably suffered to interfere with the inside diameter of the cylinder of the actuator and, to avoid this trouble, is required to be replaced with a contacting member of a special shape.
Then, the technique disclosed in Patent Document 2 requires the guide rail for supporting the rack to be fixed to the actuator body. Thus, this technique results in adding to the number of component parts and complicating the structure of the actuator.
Further, in the case of a high-output actuator of the spring return type, though the compression spring thereof is fated to assume a large size and generate a large resilient repulsive force, this compression spring is formed in a helical shape and the terminal part of this compression spring is consequently enabled to generate in increasing prominence a retracting action in the circumferential direction of the spring diameter in consequence of the expansion and contraction of the spring. Moreover, since the terminal part of the compression spring is pressed against the piston, the retracting action of the terminal part of the compression spring has the possibility of rotating the piston and causing the rack disposed integrally on the piston to tilt and unevenly collide against the pinion disposed integrally on the output shaft and consequently curtailing the service life of the actuator.
Patent Document 2 discloses a concept of providing a blocking plate disposed integrally on the terminal part of a cylinder containing a compression spring with an air vent that is adapted to admit air into the cylinder and discharge air from the cylinder.
This air vent indeed is disposed at such a position as to avoid the terminal part of the compression spring. The air vent has the possibility of being blocked by the terminal part of the compression spring when the actuator is miniaturized. The air vent also has the possibility of leaking rainwater therethrough when the actuator is used outdoors.
This invention has been developed in light of the various problems encountered by the prior art. It is aimed at providing a pneumatic actuator which is capable of preventing a piston from developing a phenomenon of inclining in the axial or rotary direction, enabling the reciprocating motion of the piston to be stably maintained for a long time, facilitating an inspection for confirming the property of sealing the cylinder and the piston and allowing the inspection to be infallibly performed quickly as well, and enabling the inspection of the operation and the inspection for detection of outer leakage to be simultaneously carried out.
It is further aimed at providing a pneumatic actuator which even in a combined operation type structure avoids suffering a compression spring to pop out during an overhaul, allows the aperture of the actuator to be adjusted as well on the compression spring-containing side, permits the interior of a cylinder containing the compression spring to be provided with an air vent incapable of leaking rainwater, and forms only a few parts projecting from the external shape of the actuator.


An optical pickup for reading information recorded on a recording surface of an optical information storage medium has a light beam source for emitting a linear light beam, and an optical system including an objective lens for converging the linear light beam as a linear image on the recording surface and collecting and emitting a light beam reflected from the recording surface. A tilt control device includes a parallel flat glass plate for refracting the reflected light beam from the optical system, a plurality of photodetector units each having a plurality of photosensitive surfaces for photoelectrically converting the light beam applied thereto from the parallel flat glass plate into a plurality of respective detected signals, an error generator for processing the detected signals from the photodetector units into a tilt error signal indicative of whether the linear light beam is applied perpendicularly to the recording surface, and an actuator responsive to the tilt error signal for controlling the objective lens positionally with respect to the optical information storage medium to apply the linear light beam perpendicularly to the recording surface.

1. Field of the Invention
The present invention relates to an optical pickup for reading recorded information from an optical information storage medium such as a compact disc, a laser video disc, or the like, and a tilt control device for use with such an optical pickup.
2. Description of the Prior Art
Some optical pickups for reading recorded information from an optical information storage medium such as a compact disc, a laser video disc, or the like have a tilt detecting device for detecting whether a light beam emitted from a light source is applied perpendicularly to the recording surface of the optical information storage medium.
One tilt detecting device for use with an optical pickup is shown in FIGS. 1(A) and 1(B) of the accompanying drawings. As shown in FIGS. 1(A) and 1(B), the tilt detecting device, generally designated by the reference numeral 200, has a semiconductor laser 31 for emitting a laser beam toward an optical disc DK, two photodetectors 32, 33 for detecting and photoelectrically converting a light beam reflected from a recording surface S.sub.2 of the optical disc DK into detected electric signals, and a differential amplifier 34 for calculating the difference between the detected signals from the photodetectors 32, 33 to produce a tilt error signal TE indicative of whether the laser beam is applied perpendicularly to the recording surface S.sub.2 of the optical disc DK.
If the semiconductor laser 31 and the photodetectors 32, 33 face properly to the optical disc DK, as shown in FIG. 1(A), then the two photodetectors 32, 33 detect equal intensities of the reflected light beam, and hence the differential amplifier 34 produces output signal of zero. If the optical disc DK is tilted with respect to the semiconductor laser 31 and the photodetectors 32, 33 as shown in FIG. l(B), the photodetector 32 detects a higher intensity of the reflected light beam than the photodetector 33, so that the differential amplifier 34 produces a positive output signal, thus detecting the tilt of the optical disc DK. A suitable control unit including an actuator may be connected to the tilt detecting device 100, thus making up a tilt control device for correcting the position of the optical pickup so that the laser beam will be applied perpendicularly to the recording surface S.sub.2 of the optical disc DK.
The tilt control device is disadvantageous in that its semiconductor laser 31 and the photodetectors 32, 33 are required in addition to the optical pickup which is used to reproduce an information signal recorded on the optical disc DK. Therefore, the entire assembly of the optical pickup and the tilt control device has a complex structure and a large size.

Optical pickup and tilt control device including a plurality of photosensitive units for generating signals indicating whether tilt correction is necessary


A differential magnetometer consisting of at least one active coil (4, 5) and a receiver coil (10) for which the windings are installed differentially, is provided with a measurement circuit (14) with a slaving device that corrects dissymmetry appearing between windings (11, 12) to eliminate residual induction at the frequency of the magnetic excitation field, intended to make the measurement coil (10) more sensitive without applying a voltage to it.

Fluxgate type magnetometers with differential structure comprise a magnetic core, at least one active coil and a receiver coil that comprises two windings arranged in series around the core such that the magnetic field produced by an excitation current in the active coil creates opposite inductions in the windings of the receiver coil, and induced currents that cancel each other since they are also opposite. They then react to ambient magnetic fields through an induction current with a frequency equal to twice the excitation frequency provided that the active coil excitation current is sufficient. The voltage thus induced at the terminals of the receiver coil is collected and measured by the measurement means.
These magnetometers have a bias (measurement error, visible when the instrument is used in a zero field) that is variable from one instrument to another, which degrades their precision and therefore limits their use in continuous field metrology applications. Furthermore, for a given magnetometer, this bias varies for example as a function of the temperature.
One of the contributions to the bias in the case of a differential structure is related to the residual excitation frequency present at the terminals of receiver coils, because of dissymmetry between the two measurement or excitation branches. When the magnetometer is then operated in field compensation mode (conventional configuration in closed loop that in particular extends its linearity), the effect is to reinject a synchronous component of the excitation frequency with a phase shift from the excitation frequency, into the two branches of the magnetic circuit.
Dissymmetry of the magnetometer consist of irregularities of the diameter of the wire or the turns, or even the number of turns, between the windings in the receiver coil or their relative positions with respect to the excitation coils that have an influence on the mutual inductance between the excitation and induction coils.

Magnetometer with structure asymmetry correction


An electrophoresis plate has a plurality of separation channels provided inside a substrate. The separation channels are arranged along the surface of the substrate without intersecting each other, and the separation channels have openings on both ends on the substrate surface. When a voltage is applied between the two ends of the channel, a sample is separated by electrophoresis along the channel. The openings on one end are placed in a matrix pattern as sample inlet ports, and the pitch of that placement is set equal to the pitch of the wells of a sample plate containing the samples to be injected into the sample inlet ports. Since the pitch of the sample inlet ports pattern is equal to the pitch of the sample plate wells, sample injection can be performed quickly and conveniently even with a large number of separation channels.

The present invention relates to an electrophoresis plate, which is used for separation by electrophoresis in fields such as biochemistry, molecular biology, and clinical practice, for example in DNA sequencing, for analyzing very minute quantities of proteins and amino acids, drugs, and the like, at high speed and with high resolution.
Electrophoresis devices have traditionally been used when analyzing very minute quantities of proteins and amino acids, and the like. There is a capillary electrophoresis device as a representative device, but it was complicated. Compensating for that drawback, an electrophoresis device having channels inside the substrate, aiming for acceleration of analysis and miniaturization of the device, is a so-called micro fluid device.
Prior electrophoresis methods using micro fluid devices are based on channels of cross injector design, having intersecting sample inlet channels in addition to separation channels (See Japanese Unexamined Patent Publication No. 2002-131279; Japanese Unexamined Patent Publication No. 2002-131280; Japanese Unexamined Patent Publication No. 2002-310990; and Japanese Unexamined Patent Publication No. 2003-166975).
However, with the cross injection method, there is a limit in the samples introduced into the separation channels due to the channel configuration, and it cannot handle diverse samples (for example, samples containing components having great differences of concentration).
Therefore, an electrophoresis plate having only separation channels in which the quantity of injected samples can be controlled by applied voltage and application time is used. That electrophoresis plate has plural separation channels inside the substrate, each of those separation channels consists of one channel, and voltage is applied between the two ends whereby the sample is separated by electrophoresis along the channel. Those separation channels are arranged along the surface of the substrate without intersecting each other, and in a manner so as to be collected from one end toward the other end, and they are made so as to avoid accumulation at the cathode end.
In the case of performing sample injection in the preprocessing process, from an MTP (Micro Type Plate) having 96 holes or 384 holes, which is commonly used as a sample plate, into an MEMS (Micro Electro Mechanical Systems) electrophoresis plate having a radial channel structure, because the pitch arrangement of the separation channels does not correspond to the pitch of the wells of the sample plate, injection of the samples on a one-by-one basis becomes necessary, and sample injection in a short time may become difficult.
An object of the present invention therefore is to provide an electrophoresis plate with which sample injection can be performed quickly and conveniently even when the number of separation channels is increased.
Further objects and advantages of the invention will be apparent from the following description of the invention.


An exemplary system server includes a first server, a second server, and a bridge board. The bridge board includes a printed circuit board and a power input positioned on the printed circuit board. The power input receives power from a power source. The first server includes a first controller and a first ground end connected to ground. The first controller includes a first detecting end connected to the power input. The second server includes a second controller and a second ground end. The second ground end connects the first detecting end to ground via the bridge board. The first controller determines whether the second server functions according to a voltage of the first detecting end.

1. Technical Field
The present disclosure relates to a server system.
2. Description of Related Art
A server system usually includes a plurality of servers and a plurality of hard disks. The servers operate independently from each other except for sharing a power supply. If a server among the servers fails to function, other servers cannot receive this information. Accordingly, operators may not be able to repair the server that fails to function in time.
Therefore, it is desirable to provide a means which can overcome the above-mentioned problems.

HONG FU JIN PRECISION INDUSTRY (ShenZhen) CO., LTD.


A method for producing an electrically conductive element is provided in which an oxidation barrier is formed through modification of one or more layers which initially were receptive to oxidation.

1. Field of the Invention
The present invention relates to semiconductor devices whose current flow is controlled by layers which are oxidized over part of their areas, and more particularly to layers which have been modified in order to control the extent and shape of the oxidized regions, and most particularly to devices, especially lasers and vertical cavity surface emitting lasers (VCSELs), which utilize such conductive elements. The present invention furthermore relates to the formation of VCSELs which emit at visible and infrared wavelengths which reside on non-GaAs substrates, and VCSELs whose emission wavelengths are precisely controlled.
2. Description of the Prior Art
Vertical-cavity surface-emitting lasers (VCSELs) whose current flow is controlled by lateral oxidation processes show the best performances of any VCSELs in terms of low threshold current and high efficiency. In oxidized VCSELs the oxidation occurs in the lateral direction from the sides of etched mesas in the VCSEL wafers, typically under the conditions of 425.degree. C. temperature with high water-vapor content. Presently however, the lateral oxidation process is controlled only through careful control of the timing, temperature, and the sizes of the mesas. This presents difficulties in the manufacturability of such VCSELs, because the current apertures may not be the same from wafer to wafer, or even within a single wafer. Furthermore, since there is no definite stopping mechanism for the oxidation process other than removal from the oxidation environment, the reliability of oxidized VCSELs has not been very high. VCSELs or any other light emitting devices employing laterally oxidized layers have been strictly limited only to structures which have been grown upon gallium arsenide (GaAs) substrates and emit light at wavelengths limited to the region bounded by 0.63 .mu.m and 1.1 .mu.m. Since VCSELs are presently the subject of intense research and development, a great deal of results and advancements are published monthly. are presently the subject of intense research and development, a great deal of results and advancements are published monthly.
Most reports of the oxidation process describe oxidation in layers of aluminum arsenide (AlAs) or aluminum gallium arsenide (Al.sub.x Ga.sub.1-x As) where the Al concentration, x, is close to unity. As reported by Choquette, et al. in "Low threshold Voltage Vertical-Cavity Lasers Fabricated by Selective Oxidation," which appeared in Electronics Letters, volume 24, pp. 2043-2044, 1994, reducing the Al concentration from x=1.0 to x=0.96 reduces the oxidation rate by more than one order of magnitude. At x=0.87, the oxidation rate is reduced by two orders of magnitude compared to x=1.0. Due to the extreme sensitivity of the oxidation rate to the Al concentration and the fact that Al concentration may vary from wafer to wafer or even over the area of a single wafer, the manufacturability of oxidized VCSELs has been questioned. In the very recent publication by Choquette et al., entitled "Fabrication and Performance of Selectively Oxidized Vertical-Cavity Lasers," which appeared in IEEE Photonics Technology Letters, vol. 7, pp. 1237-1239, (November, 1995), this problem was noted followed by the observation that "Therefore, stringent compositional control may be necessary for wafer scale manufacture of uniformly sized oxide apertures."
A limited form of lateral control of oxidation is reported in the publication by Dallesasse, et al. entitled "Hydrolyzation Oxidation of Al.sub.x Ga.sub.1-x As-AlAs-GaAs Quantum Well Heterostructures and Superlattices," which appeared in Applied Physics Letters, volume 57, pp. 2844-2846, 1990. The same work is also described in U.S. Pat. No.'s 5,262,360 and 5,373,522, both by Holonyak and Dallesasse. In that work, GaAs-AlAs superlattices were interdiffused in selected regions by impurity-induced layer disordering (IILD). The interdiffusion was essentially complete in the selected regions, thus the interdiffused regions comprised an AlGaAs compound having an Al concentration being approximately uniform and equal to the average Al concentration of the original constituent AlAs and GaAs layers. The oxidation proceeded through the superlattice regions but not significantly into the interdiffused regions. The superlattice was not doped and contained no other structure from which to fabricate any electronic or optoelectronic device. No attempt was made to form any kind of conductive aperture or boundary.
Implantation enhanced interdiffusion (IEI) is another method for interdiffusing thin semiconductor layers and is described by Cibert et al. in the publication entitled "Kinetics of Implantation Enhanced Interdiffusion of Ga and Al at GaAs-Al.sub.x Ga.sub.1-x As Interfaces," which appeared in Applied Physics Letters, volume 49, pp. 223-225, 1986.
Due to the much lower refractive index of aluminum oxide compared to AlAs (about 1.6 compared to 3.0) oxidation of an AlAs layer within a VCSEL cavity shifts the cavity resonance to a shorter wavelength as reported by Choquette et al. in "Cavity Characteristics of Selectively Oxidized Vertical-Cavity Lasers," which appeared in Applied Physics Letters, volume 66, pp. 3413-3415, in 1995.
Formation of VCSELs which emit a wavelengths longer than about 1.1 .mu.m has been difficult in the prior art. Despite numerous efforts toward developing 1.3-1.55 .mu.m emitting VCSELs, only recently has room-temperature continuous-wave emission been reported as in the publication by Babic et al. entitled "Room-Temperature Continuous-Wave Operation of 1.54 -.mu.m Vertical-Cavity Lasers," which appeared in IEEE Photonics Technology Letters, vol. 7, pp. 1225-1227 (November, 1995). In that work, fabrication was accomplished by fusing semiconductor mirrors and active regions epitaxially grown on three separate substrates. Another approach to forming 1.3-1.55 .mu.m emitting VCSELs is to grow semiconductor mirrors of aluminum arsenide antimonide (AlAsSb) and aluminum gallium arsenide antimonide (AlGaAsSb) on indium phosphide (InP) substrates as reported by Blum et al., in the publication entitled "Electrical and Optical Characteristics of AlAsSb/GaAsSb Distributed Bragg Reflectors for Surface Emitting Lasers," which appeared in Applied Physics Letters, vol. 67, pp. 3233-3235 (November 1995).

Method for producing an electrically conductive element for semiconductor light emitting devices


A new and distinct cultivar of Astilbe plant named ‘Vision in White’, characterized by its upright and sturdy plant habit; strong and healthy foliage; freely and uniformly flowering habit; white-colored flowers; and good garden performance.

The present invention relates to a new and distinct cultivar of Astilbe, botanically known as Astilbe chinensis and hereinafter referred to by the name 'Vision in White'.
The new Astilbe is a product of a planned breeding program conducted by the Inventor in Noorden, The Netherlands. The objective of the breeding program was to create new vigorous Astilbe cultivars with healthy foliage and attractive flower coloration.
The new Astilbe originated from a cross-pollination made by the Inventor in 2003 in Noorden, The Netherlands, of the Astilbe chinensis cultivar Vision, not patented, as the female, or seed, parent with the Astilbe chinensis cultivar Düsseldorf, not patented, as the male, or pollen, parent. The new Astilbe was discovered and selected by the Inventor as a single flowering plant within the progeny of the stated cross-pollination in a controlled environment in Noorden, The Netherlands in 2005.
Asexual reproduction of the new Astilbe by divisions in a controlled environment in Noorden, The Netherlands since 2005, has shown that the unique features of this new Astilbe are stable and reproduced true to type in successive generations.


Connector housings (11, 12) to be mounted on a printed circuit board (100) have a plurality of rows of contacts (13, 14) extending from wall surfaces of the housing (11, 12). These contacts (13, 14) are soldered to conductive pads (23) of a flexible circuit (20). The flexible circuit (20), bent in a generally U-shaped, about an insertion portion (31) of a metallic guide portion (30) which is to be inserted between rows of contacts (50) of a mating connector (40) for interconnection therebetween. The guide member (30) preferably engages a ground conductor (176) on the reverse surface of the flexible substrate and includes extending portions (142) to groundingly engage conductive member (43, 124) positioned at both ends of the housing. In an alternate embodiment strengthening plates may be adhered to the flexible circuit between the opposed arrays of conductive pads and ground contact pads.

Advances in electronic devices including microprocessors have created a large market for compact electronic apparatus using memory or PC cards, hard disk drives (HDDs), etc. A docking connector or a memory card connector is used in such electronic apparati. The docking connector is used to interconnect another similar electronic apparatus for creating a network and also to connect peripheral equipment such as a submemory apparatus. A memory card connector receives one or more memory card or an HDD for electrical connection thereto.
Recently, needs have arisen for card type devices known a PC cards for expansion or additional performance of compact electronic equipment such as notebook personal computers. Such PC cards are normally received in a PC card connector installed in a compact electronic equipment to provide added memory capacity or interfacing with external devices such as peripheral equipment. Typically, PC card connectors have dual stacked connector mating portions to permit reception of three types of PC cards, i.e., Type I, Type II and Type III.
These docking connectors and PC or memory card connectors include a plurality of contacts often more than one hundred disposed in a matrix having a plurality of rows. Such contacts are bent at right angles or in an L-shape with respect to the connector and are soldered to respective conductive paths or traces on a main PC board. One example of such memory card connector is disclosed in U.S. Pat. No. 5,324,204. In this particular example, four rows of contacts are bent in a staggered relationship to be connected to the main PC board in eight rows.
Typical examples of such connectors also are disclosed in Japanese Patent Publication, No. 6-332573 and Japanese UM Publication No. 6-56992. The former connector has contacts aligned in a connector housing and bent at substantially right angles at the rear position to be connected to a rain circuit board. In the latter connector, contacts of dual stacked connectors extend at their rear positions toward each other, i.e., toward the center position to be connected to an auxiliary circuit board at the center position, thereby interconnecting the auxiliary and main circuit boards by the board-to-board connector.
Unfortunately, as electronic equipment becomes more compact, a higher density of contacts is required. The individual contacts, therefore, have smaller dimensions and pitch, which makes it difficult to form reliable connections with a main circuit board using a connector having relatively long solder tines of the contacts of the former connector. Although the latter connector is effective to realize relatively fine pitch connections, the connector requires a larger number of components, thus making it more difficult to manufacture and more expensive.
Moreover, a standard to form signal and ground (SG) of PC card connectors has been added recently. One object is to isolate signals to be transmitted through one connector from those transmitted through another connector, thereby preventing noise due to cross talk. Unfortunately, however, such noise protection is not always sufficient in conventional connectors.
Additionally, in the above conventional connectors, the connection or mounting location of the connector or its contacts on a main circuit board is required to be predetermined, thereby restricting the design of the main circuit board and precise manufacture of conductive through hole patterns, etc. with small tolerances. It is, therefore, desirable to provide flexibility in connection or mounting.
Using a flexible circuit (FC) for interconnecting circuits on a substrate such as a small-size printed circuit board (PCB) and high-density-mounted electronic equipment is known in the art. Such an electrical connector for an FC generally comprises a plurality of contacts to be engaged with conductive pads formed on the FC, a housing for disposing and holding the contacts, and a movable plastic cover or other member for pushing the FC into the housing and the conductive pads formed thereon into positive engagement with the contacts in the housing. Examples of conventional electrical connectors for FC are disclosed in a Japanese Patent Publication No. 61-131382, a Japanese UM Publication No. 2-120780, and a Japanese Patent Publication No. 5-251140.
U.S. Pat. No. 3,923,364 discloses an electrical connector assembly including a housing having a plurality of contacts disposed along an elongate opening; a shielded flexible substrate having a width corresponding to the opening of the housing and conductive signal traces and pads and ground conductive pads on one surface thereof corresponding to the contacts in the housing; and a guide member having a plate portion to be disposed in a flexible substrate bent in a generally U-shape with the one surface outside to be inserted into the opening of the housing whereby, upon inserting the guide member and substrate into the housing opening, the signal and ground pads on the one surface of the substrate are electrically engaged to corresponding contacts in the housing.
As electronic equipment becomes smaller with a higher density of contacts, e.g., the pitch of the contacts is less than 0.5 mm, the dimensions of the contacts to be used therein will also become smaller and, therefore, be more easy to deform. It is very difficult to accurately position the contacts, especially their solder-terminating portions, in the desired location and to maintain them so as not to deform the contacts upon handing and mounting the connector on to the substrate.
Also, for the electrical connector utilizing the FC, it is difficult to precisely and firmly urge the movable plastic cover to engage over the full width of the FC with the plurality of contacts without having some deformation over the full width of the FC. Accordingly, reliability of connection between the conductive pads and the contacts has been decreased.
Therefore, an object of this invention is to provide a small and high density electrical connector assembly, that utilizes the FC and enables simple structure and easy handling.
It is another object of this invention to provide an electrical connector assembly having a ground function and permitting easy handling in which the plurality of the conductive pads on the FC and the contacts in the housing are interconnected with high reliability.
It is yet another object of this invention to provide an electrical connector assembly for card bus, which enables one or more memory card connector etc. to connect easily and reliably to the PC board.
In order to solve the problems of the prior art electrical connector assembly and to achieve the above mentioned objects, the electrical connector assembly of the present invention comprises a housing having plural rows of contacts, a substrate, such as a flexible printed circuit board (FC) to be connected to the contacts of the housing at both ends of the flexible printed circuit board, said printed circuit board having a plurality of conductive traces and pads, and a guide member to be inserted in the FC, the guide member being bent in a generally U-shape to force the FC between rows of contacts of a corresponding connector to interconnect the conductive traces and contacts.
In accordance with one aspect of the present invention, the electrical connector assembly includes a housing having a plurality of contacts disposed along an elongate opening; a flexible substrate having a width corresponding to the opening of the housing and conductive traces on one surface thereof corresponding to the contacts in the housing; and a guide member having a plate portion to be disposed in a flexible substrate bent in a generally U-shape with the one surface outside to be inserted into the opening of the housing. The connector assembly is characterized in that: the housing includes a ground conductive member at at least one end thereof; the flexible substrate is formed with a ground conductor on the other surface thereof; and the guide member is a conductive member adapted to further provide a connection to ground for the assembly whereby the contacts and the conductive traces are electrically connected by the force exerted by the guide member on the flexible substrate and the ground conductor of the substrate is connected to the ground conductive member of the housing by the guide member.
In one embodiment of the invention using a flexible substrate having conductive traces on one surface, the assembly further includes strengthening plates disposed on the other surface of the substrate at the locations corresponding to the conductive pads.
One aspect of the present invention is an FC having two arrays of corresponding conductive pads and conductive traces on one surface with the plurality of conductive pads of the arrays arranged in rows in an opposed relationship. A plurality of openings are disposed between the arrays leaving narrow bridge portions between adjacent openings. Strengthening plates are attached to the reversed surface at the positions corresponding to the conductive pads with portions of the strengthening plates extending into the openings by a predetermined length.
Also, another aspect of the present invention is a flexible circuit (FC) comprising conductive traces on one surface of a central film, a ground layer on the reverse surface, and cover layers disposed to cover the conductive traces and the ground layer. A plurality of openings are formed in the cover layers substantially in rows at selected locations that avoid the conductive traces.
The FC according to the present invention has openings in the direction of the width at substantially center position between the rows of the conductive pads. The openings define the relatively narrow bridge portions of the FC. The FC has a pair of strengthening plates adhered to both sides of the openings and at least one surface of the FC. The pair of strengthening plates have edges extending into the openings by a desired length from both sides thereof.
Additionally, the FC according to the present invention has a plurality of recesses arranged substantially in rows near the bent portion. The recesses are preferably formed by removing a part of one layer of a multiple-layer FC, thereby allowing the FC to bend smoothly at a desired position.
The FC is bent or folded along the bridge portions before being inserted into a connector along with a guide member, and upon full insertion of the board and guide member, the conductive pads of the FC are electrically connected with contacts in the connector. The edge portions of the strengthening plates then abut the bottom in the housing for proper positioning of the FC in the connector, thereby assuring reliable electrical connection between the conductive pads and the contacts. Also, it is bent at a desired angle, preferably a right angle along the recesses, thereby permitting connection to a connector such as the PC card connector or other device at the edge portion. Since the electrical connector assembly comprises a FC with no individual contacts bent at right angle with respect to a wall or L-shape as seen in the prior art electrical connector assembly, the connector of the present invention eliminates deformation of the guide between the contacts and disengagement and short circuit caused therebetween. Accordingly, stable electrical connections and easy handling are achieved. Also, the structure having the FC connected to the contacts on the housing at the both ends thereof enables high density.
According to another aspect of the present invention, the electrical connector comprises a housing having two rows of contacts alone an elongate opening, a flexible printed circuit board having a plurality of conductive traces on a surface corresponding to these contacts, and a guide member having a generally planer portion to be inserted into a U-shaped bent portion of the flexible printed circuit board, wherein the conductive traces on the flexible printed circuit board are forced between the rows of the contacts by means of the guide member for establishing electrical interconnection between the conductive traces and the contacts in the housing, thus electrically connecting the contacts with corresponding contacts of at least one electrical connector terminated to the ends of the FC.
According to the electrical connector assembly, it is possible to connect the high frequency signals to the contacts through the conductive traces on the surface of the FC. The FC is bent in a U-shape to envelope the guide such that the guide electrically engages the ground conductor of the FC board and upon inserting the FC into the housing, the guide electrically engages the ground conductive members of the housing. Since all the conductive traces formed on the one surface of the FC can be signal traces, a high density and high frequency electrical connector is obtained.


A frequency synthesizing apparatus and method for a multi-band radio frequency (RF) receiver is provided. The frequency synthesizing apparatus includes a simple circuit configuration with a single SSB mixer and thus, may synthesize six high frequency signals. Signals to be inputted into the SSB mixer include a first signal and a second signal. The first signal is generated based on a VCO and a PPF. Also, the second signal is selected from a plurality of frequency divided signals which are generated by dividing a signal generated in the VCO via a plurality of dividers.

1. Field of the Invention
The present invention relates to a frequency synthesizing apparatus for a multi-band radio frequency (RF) receiver, and more particularly, to a multi-frequency synthesizing apparatus and method which can reduce a circuit area and may be low powered.
2. Description of the Related Art
A high speed wireless data transceiving system such as a cellular phone, a digital multimedia broadcasting (DMB) phone, a personal digital assistant (PDA), etc., needs a frequency synthesizer or a frequency mixer processing multi-tones for frequency down conversion in a transceiver. For example, a multi-frequency synthesizer is utilized to receive an RF signal and convert the received RF signal into a baseband signal, in all bands utilizing a Multi-Band Orthogonal Frequency Division Multiplexing (MB-OFDM) scheme for a fourth generation mobile communication system or a ubiquitous system.
FIG. 1 is a diagram illustrating a multi-band of an OFDM scheme according to the related art. As shown in FIG. 1, five band groups #1, #2, #3, #4 and #5 are allowed to be allocated for an MB-OFDM scheme, i.e., between 3.1 and 10.6 GHz. The Federal Communications Commission (FCC) regulates that the band group #1 must be utilized, and other remaining band groups #2 to #5 may be utilized as necessary.
The fourth generation mobile communication system provides integrated services such as a voice, an image, multimedia, access to the Internet, a voice mail, an instance message, etc via one terminal with utilizing a satellite network, a wireless local area network (WLAN) and the Internet. As potential demands of the band group #1 for the fourth generation mobile communication increase, utilization of another band group is currently being discussed. Also, since a lot of interference from a WLAN utilizing an identical frequency band exists in a center frequency of the band group #2, i.e., in a 5544 MHz band, services of the fourth generation mobile communication utilizing a frequency band of the band group #3, #4 or #5 need to be developed.
FIG. 2 is a diagram illustrating a related art frequency synthesizer 200 for generating a multi-frequency signal. A predetermined receiver (Rx) mixer is utilized for an RF receiver to down convert a multi-band RF signal into a baseband. In this instance, a local signal RFO that is output from the frequency synthesizer 200 may be supplied to be synthesized with a received RF signal.
To obtain a multi-band local signal RFO, a single side band (SSB) mixer 230 is utilized. In this instance, the SSB mixer 230 generates a signal whose frequency is an addition of frequencies or a difference of frequencies between two received signals. However, in this case, the single SSB mixer 230 can only generate one of two components which are an addition of frequencies or a difference of frequencies between the two received signals. Accordingly, a plurality of SSB mixers and switches are generally utilized for down converting a large number of multi-band RF signals in a ubiquitous system.
The SSB mixers receive high frequency signals, RF1, RF2, . . . , from a voltage controlled oscillator (VCO)/frequency divider (DIV) 220, which is connected to a phase locked loop (PLL) 210, and synthesize a necessary frequency signal. In this instance, a plurality of PLLs, VCOs or DIVs may be utilized. Also, switches are needed for selecting any one of multi-frequency signals synthesized in the SSB mixers, which is necessary for down converting a received RF signal.
As described above, necessary multi-band signals may be generated by utilizing a large number of SSB mixers, PLLs, VCOs or DIVs. However, in this case, a required circuit area may be unacceptably increased to embody a PLL, a VCO/DIV and SSB mixers, and a huge amount of power may also be consumed. Also, since a large number of harmonics are generated that cause undesired tones, a stable and clean local signal LO may not be obtained.

Multi-frequency synthesizing apparatus and method for multi-band RF receiver


A method selects the data rate for pulse code modulation upstream transmission by determining an approximate transmit power before the upstream transmission reaches a transmit equalizer based on a recorder power output and a distance halfway between an outermost constellation point and a point following the outermost point. The determined approximate transmit power is multiplied by the power of the transmit equalizer to determine a post-equalizer transmit value. A data rate is selected which is less than a predetermined regulatory limit.

Personal computers connecting to networks through the public switched telephone system (PSTN) typically use a modem to dial-up a network connection through analog telephone lines. These client, or end user, modems transmit data signals converted to digital source through an analog channel through a network. Due to the increase in data, voice, and facsimile traffic over the telecommunications infrastructure, methods to increase the digital and analog transfer rates through modems over telephone lines are extremely useful and necessary to adhere to International Telecommunication Union (ITU) standards.
The Telecommunication Standardization Sector of the ITU (ITU-T) adopted V.34 Recommendation in 1994, which is incorporated herein, to define modem operating speeds rom 28.8 kilobyte per second (kbps) up to 33.6 kbps. However, data transfer rates are limited over the PSTN. In modems built to V.34 standards of the International Telecommunications Union (ITU), and all previous voice-band modem standards, carrier-modulated quadrature amplitude modulation (QAM) is used to quantize the analog signals using u-law (or A-law for some standards outside of the U.S.) pulse code modulation (PCM) codecs. In such a system, the carrier frequency and symbol rate are chosen to match the channel, not the codec. However, in many cases there is a direct digital connection upstream of the analog client modem between a central office (CO) of the PSTN and a server modem on a digital network. PCM modems are built to take advantage of networks used by internet service providers or others connected to the PSTN through a digital connection, such as T1 in the United States and E1 in Europe. PCM modems use either standards for "PCM downstream" modulation, as described in ITU V.90, or "PCM upstream, as described in ITU V.92 recommendations. A connection between a client modem on a local loop of the PSTN and a connection on the digital network can be referred to as a "PCM channel".
In PCM downstream, data is transmitted in PCM mode downstream from a central office to an end user's analog modem, i.e. from server to client. The upstream digital PCM modem transmits over a digital network in eight bit digital words called octets that correspond to different central office codec output levels. At the client modem's central office, the octets are converted to analog levels which are transmitted over an analog loop. The client PCM modem then converts the analog levels back to digital signals, or pulse code amplitude (PAM) signals, and into equalized digital levels. The equalized digital levels are ideally mapped back into the originally transmitted octets that the octets represent
When using PCM downstream modulation, the client modem synchronizes to the central office codec and tries to determine exactly which PCM sample was transmitted in each sample. In codecs throughout the world, the codec clock is 8000 Hz. Since there are 255 different μ-law levels and 256 different A-law levels, the data rates could go as high as nearly 64 kbps (8 bits/sample at 8000 samples/second). Practically, because the smallest levels are often too small to distinguish and because of regulatory power limits on the transmit signal, the highest data rate is listed as 56 kbps although even that is usually higher than what most channels will support. In PCM downstream, the client modem must implement an equalizer to undo the effects of intersymbol interference caused by the channel (the telephone line plus the analog front-end of the codec and client modems) in order to recover the PCM levels.
In PCM upstream modulation, the client modem transmits analog levels corresponding to data to be transmitted to the digital server modem over an analog telecommunications line. The analog levels are modified by the channel characteristics of the analog line. The modified levels are quantized to form octets by a codec in the central office. In PCM upstream, the channel comes before the codec, further limiting the highest possible data rate. The codec then transmits the octets to the PCM server modem over the digital network. At the server modem, the transmitted levels are demodulated from the octets, thereby recovering the data sent from the client modem.
If the client modem were simply to transmit PCM levels, the channel would distort the levels so that when it reached the codec, they would not resemble the transmitted levels at all. The server modem is not able to equalize the receive signals until after the codec and therefore can not limit the effect of quantization noise. In order to take advantage of the PCM codec in the upstream direction, the client modem must implement an equalizer in the transmitter to undo the effects of intersymbol interference.
There are a number of factors that limit the PCM upstream data rate more than the PCM downstream data rate and provide additional challenges. Regulatory limits on the client modem transmit power mean that the higher the upstream channel attenuation, the lower the upstream data rate. In the downstream direction, only the signal-to-noise ratio (SNR) limits downstream performance. The echo from the downstream signal is added before the codec. Even a perfect echo canceller in the server modem can not remove the quantization noise caused by the echo. The equalizer in the client transmitter can not continually adapt to changing channel conditions as can the receive equalizer used for PCM downstream. The only way to adapt the transmit equalizer is for the server to notify the client through a rate renegotiation. The timing recovery in the upstream direction is more difficult that in the downstream direction. Due to these and other problems in PCM upstream transmissions, the levels transmitted by the client PCM modem are modified. Since these modified levels are quantized to form octets by the codec, and not the levels that are actually transmitted, it can be difficult for the server modem to accurately determine from the octets the data being transmitted by the client modem.
In general, signal constellations consist of complex-valued signal points which lie on an N-dimensional grid. User data is encoded into constellation points. One constellation point is transmitted during each symbol period. The higher the symbol rate and the more constellation points, the higher the data rate.
Codes are often used to prevent certain sequences of constellation points to reduce the likelihood of decoder errors. Recommendation V.92 states that the convolutional encoders from Recommendation V.34 shall be used for V.92. ITU-T Recommendation V.34 are standards for a modem operating at data signaling rates of up to 33,600 bits/s for use on the general switched telephone network and on leased point-to-point 2-wire telephone type circuits. The conventional approach to selecting the signal points of a PCM-derived constellation would be to choose ones of the quantization levels that are equally spaced and for levels for which the minimum distance between the levels is large enough to ensure reliable operation. The minimum distance criterion, in particular, is a critical design parameter because the transmitted signal points, when they traverse a local analog line, are inevitably displaced in signal space by channel noise and other channel impairments. Thus, the extent to which a transmitted signal may be erroneously detected at a receiving modem depends on the distance between the transmitted signal point and its nearest neighbor points in the PCM-derived constellation. Such a scheme will achieve a certain expected level of error rate performance, which many be adequate for particular applications. If a higher level of error rate performance is required, it is well known for voice-band modem transmissions to apply channel coding methods such as trellis coded modulation to an existing scheme to achieve an effective minimum distance between the signal points that allows for higher transfer rates with an equivalent level of performance. However, additional coding adds implementational complexity and transmission delays to system.
The standard may use trellis coding for all data signaling rates. Trellis encoding is a method for improving noise immunity using a convolutional coder to select a sequence of subsets in a partitioned signal constellation. The trellis encoders used in the ITU recommendation are used in a feedback structure where the inputs to the trellis encoder are derived from the signal points. Trellis coded modulation (TCM) is one of the coding standards recommended under the V.92 modem communications standard. Trellis codes using lattices of dimensions larger than two have been constructed and have several advantages. One dimensional (1D) symbols are grouped to form four-dimensional (4D) symbol intervals. Multidimensional trellis code signals as a basis for signal constellations are a theoretical concept, since, in practice, multidimensional signals are transmitted as sequences of one or two dimensional signals. Doubling the constellation size while maintaining constant energy reduces the minimum distance within the constellation, and this reduction has to be compensated for by the code before any coding gain can be achieved.
The decoding operation comprises finding the correct path through the trellis that most closely represents the received binary sequence. The decoder finds a path for the received binary sequence that has the minimum distance from the received sequence. The iterative procedure accomplishing the decoding is the Viterbi algorithm. The algorithm uses forward dynamic programming to select the best, or minimum distance, path through a trellis. At each node, in the trellis, the only path retained is the best path, therefore limiting the number of retained paths at any time instant to the total number of trellis nodes at that time.
The ability to design an appropriate transmission constellation plays a critical role in producing high quality modem transmissions in PCM upstream. The signal points of the PCM-derived signal constellation comprise points selected from PCM quantization levels, which eliminates PCM quantization noise as a source of noise in the overall system. What gets transmitted is the quantization level that is closest to the actual signal amplitude, for example an 8-bit word which represents that level. The discrepancy between the actual amplitude and the transmitted representation of that amplitude appears in the receiving modem as quantization noise. The PCM-derived signal constellation can be a u-law or A-law quantization that uses 255 or 256 quantization levels.

Method for selecting the data rate for PCM upstream transmission


A digital video/audio recording and reproducing apparatus comprising a video signal high-efficiency encoder having a variable reduction rate, an audio signal high-efficiency encoder having a variable reduction rate, and a controller for controlling the reduction rates in both of the high-efficiency encoders. The reduction rates in both of the high-efficiency encoders are controlled in such a manner that the sum of the information amount of the video signal and that of the audio signal, after high-efficiency encoding, is maintained constant. When recording multi-channel audio signals, the reduction rates in both of the high-efficiency encoders are controlled according to the number of audio signal channels to be recorded. The high frequency components of the high-efficiency encoded video and audio signals are recorded at the end portions of recording tracks on a magnetic tape, while the low frequency components thereof are recorded in the central portion of the recording tracks.

1. Field of the Invention
The present invention relates to a digital video/audio recording and reproducing apparatus for compressing and encoding digitized video and audio signals, recording the thus encoded data on a recording medium such as a magnetic tape, and reproducing the data recorded on the recording medium.
2. Description of Related Art
It is known to provide a digital video/audio recording and reproducing apparatus for digitizing video and audio signals simultaneously, recording the digitized signals on a recording medium such as a magnetic tape, magnetic disk, or optical disk, and reproducing simultaneously both the video and audio signals recorded on the recording medium for conversion into an analog representation. FIG. 1 is a block diagram showing the configuration of such a known digital video/audio recording and reproducing apparatus, disclosed in the July 1988 issue of Hosho Gijutsu (Broadcast Technology).
In FIG. 1, the numerals 1 and 2 designate a video A/D converter and an audio A/D converter, respectively, for converting an input analog video signal and an input four-channel analog audio signal into a digital representation. The video signal digitized by the video A/D converter 1 is supplied to a C2 encoder 3, which derives a C2 parity in the error-correction encoding of the video signal, appends it to the video signal, and delivers the video signal with the C2 parity to an interleave 4 where the video signal is shuffled. The audio signal digitized by the audio A/D converter 2 is supplied to an audio error-correction encoder 5 where the digitized audio signal is error-correction encoded. The video signal shuffled in the interleave 4 and the audio signal error-correction encoded by the audio error-correction encoder 5 are combined in an adder and delivered to a C1 encoder 6. The C1 encoder 6 derives a C1 parity for the combined data, appends it to the data, and delivers the data with the C1 parity to a modulator 7 where the error-correction encoded data is encoded for recording. The data encoded for recording is recorded on a magnetic tape 8 by means of a magnetic head 10 mounted on a rotating drum 9.
The reference numerals 11 to 19 indicate components comprising a reproduction system, wherein the numeral 11 designates a demodulator for decoding the replay data played back from the magnetic tape 8. The data thus decoded is directed to a C1 decoder 12 which performs error correction based on the C1 parity word and delivers the error-corrected replay data to an A/V separation circuit 13. The A/V separation circuit 13 separates the replay data into a video signal and an audio signal and supplies the video signal to a deinterleave 14 and the audio signal to an audio error-correction decoder 18. The deinterleave 14 deshuffles the supplied video signal and delivers the deshuffled video signal to a C2 decoder 15 which performs error-correction based on the C2 parity word and delivers the error corrected video signal to an interpolation circuit 16. The interpolation circuit 16 performs interpolation on the video signal if there are any uncorrectable errors, and after processing, delivers the video signal to a video D/A converter 17 which converts the digital video signal into an analog signal for output. The audio error-correction decoder 18 performs error-correction on the supplied audio signal and delivers the error-corrected audio signal to an audio D/A converter 19 which converts the digital audio signal into an analog signal for output.
The operation of the above apparatus will now be described.
The input analog video signal is converted into a digital signal by the video A/D converter 1, and the digitized video signal is supplied to the C2 encoder 3 which appends the C2 parity for error correction. The video signal with the C2 parity is read into the interleave 4 where prescribed shuffling is performed on the video signal, after which the video signal is fed to the adder. On the other hand, the input analog audio signal is digitized by the A/D converter 2 and error-correction encoded by the audio error-correction encoder 5, after which the audio signal is fed to the adder where it is combined with the video signal. The combined data is fed to the C1 encoder 6 where the C1 parity is appended. The shuffled and error-correction encoded data is supplied to the modulator 7 which encodes it for recording. The data is now recorded on the magnetic tape 8 by means of the magnetic head 10. FIG. 2 shows the signal recording format recorded on the magnetic tape 8. The video signal and the four-channel audio signal are recorded in different areas on the same track, the audio signal being recorded outwardly of the ends of the video signal.
In the reproduction system, the digital data played back by the magnetic head 10 is fed to the demodulator 11 for decoding, after which the C1 decoder 12 performs error correction based on the C1 parity word. The output data from the C1 decoder 12 is separated into a video signal and an audio signal by the A/V separation circuit 13. The audio signal is processed by the audio error-correction decoder 18 and then converted by the audio D/A converter into a four-channel analog signal for sound reproduction. On the other hand, the video signal is deshuffled by the deinterleave 14 to rearrange it into the original order, after which the C2 decoder 15 performs error correction based on the C2 parity word; if there are any uncorrectable errors, error flags are attached, and the interpolation circuit 16 performs one-dimensional or two-dimensional interpolation on the video signal, the thus processed video signal then being converted by the video D/A converter 17 into an analog video signal for picture reproduction.
However, the conventional digital video/audio recording and reproducing apparatus having the above construction has the disadvantage that in order to reduce the overall size of the apparatus, if the size of the recording medium (magnetic tape) is made smaller, a shorter recording time will have to be tolerated, and if the size of the magnetic head is reduced, the recording data transfer rate (information amount) will drop, resulting in degradation in both the picture and the sound quality.
Furthermore, because of the fixed structure of the video signal recording areas and the audio signal recording areas on the recording medium (magnetic tape), as shown in FIG. 2, the maximum number of recordable audio signal channels is determined by the recording format, which gives rise to the problem that the number of audio signal channels cannot be increased beyond the predetermined maximum number; therefore, a digital video/audio recording and reproducing apparatus designed for two-channel audio recording, for example, cannot be used for recording three or more audio signal channels by using the same recording format.
Generally, in magnetic tape recording using a rotating magnetic head, the reproduction signal quality obtained from the ends of the recording tracks is inferior to that obtained from the center thereof, since errors frequently occur in the reproduction signal from the ends of the tracks. Presumably, this is because the magnetic head to magnetic tape contact characteristic is unstable at the ends of the recording tracks compared to the center thereof. In digital recording and reproducing apparatus for business use, since the recording density is set at a relatively low rate to maintain reliability, the signal quality acceptable for practical use can be obtained even from the ends of the recording tracks. However, the recording format having audio signals recorded at the ends of the tracks as shown in FIG. 2, when applied to a digital video/audio recording and reproducing apparatus designed for a higher recording density, gives rise to the problem that there occurs degradation in the sound quality since the signal quality degrades at the ends of the tracks. On the other hand, in a recording format in which the video signal recording areas are disposed at the ends of the recording tracks, degradation in the picture quality will result. Thus, the degradation of the reproduction signal quality at the ends of the tracks has the problem of causing errors in the reproduced video or audio signals.

Apparatus for controlling a sum of a varying information amount of a video signal and a varying information amount of an audio signal so that the sum is within a predetermined amount of data range


The unmanned flight equipment includes an aerial vehicle capable of flying in an unmanned manner; a linear member configured to be suspended from the aerial vehicle and to hold a delivery target at a lower end thereof; a contact detection unit configured to detect contact with the delivery target or contact with the linear member; and a separation unit configured to separate the delivery target or the liner member based on a detection result of the contact detection unit.

It has been under consideration to use an aerial vehicle that can fly in an unmanned manner, such as the so-called drone, to deliver a cargo. Such an aerial vehicle is provided with a box or the like for accommodating a cargo, and the cargo is delivered to a receiver while the box is opened in a state where the aerial vehicle is on the ground. In this case, a flat place having at least a certain area that allows the aerial vehicle to land is used as a place for delivering the cargo.
In view of this, as disclosed in Patent Documents 1 and 2 cited below, it has been also under consideration to use an aerial vehicle that retains a linear member, such as a wire or a rope, the linear member being suspended from the aerial vehicle and holding a delivery target (that may include a cargo and a container accommodating the cargo) at its lower end. The aerial vehicle of this type delivers the cargo while staying in midair without having to land on the ground. According to this method, it is possible to deliver a cargo, provided that a relatively small space where the cargo can be placed is available.
In the case where a delivery target is held by a linear member suspended from an aerial vehicle, an external force such as wind may act on the delivery target or the linear member so as to destabilize the flight state of the aerial vehicle. Therefore, the unmanned flight equipment disclosed in Patent Document 1 includes an adjustment means at a fixing device that fixes a string-like member to a body of the aerial vehicle, the adjustment means adjusting the way of fixing the string-like member in accordance with an attitude of the body such that the center of gravity of the body is on the extension of the vertical line of the string-like member having a cargo hung thereon. As a result, the load of the cargo constantly acts on the center of gravity of the aerial vehicle, thereby enabling the unmanned flight equipment of Patent Document 1 to fly stably.
The delivery apparatus disclosed in Patent Document 2 includes an unmanned aircraft, a main wire suspended from a body of the unmanned aircraft, and an auxiliary wire coupled to a portion of the main wire located toward a fixed end with respect to a free end of the main wire, the auxiliary wire extending along the main wire and having an end located outside with respect to the free end of the main wire. This delivery apparatus is configured such that an operator attaches a cargo to the end of the auxiliary wire while the auxiliary wire is loose, so that a situation can be avoided in which the operator destabilizes the attitude of the unmanned aircraft by pulling the main wire when attaching the cargo.    Patent Document 1: Japanese Unexamined Patent Application, Publication No. 2018-90095    Patent Document 2: Japanese Unexamined Patent Application, Publication No. 2017-87898

Unmanned flight equipment and delivery method