A rotation detection sensor for detecting both rotational position and direction of a rotating body with a gear includes a magnet, multiple magnetic sensors, a rotational position detection circuit, and a rotational direction detection circuit. The magnet produces a magnetic field directed to a gear tooth of the rotating body. When the rotating body rotates, the magnetic sensors output sensor signals shifted in phase from each other. The rotational position detection circuit performs a differential operation on the sensor signals received from at least two magnetic sensors and outputs a rotational position signal. The rotational direction detection circuit outputs a rotational direction signal based on the position signal and the sensor signal received from at least one of the at least two magnetic sensors.

U.S. Pat. No. 6,452,381 corresponding to JP-A-H11-237256 discloses a rotation detection sensor for detecting a rotational position of a rotating body with gear teeth. This type of rotation detection sensor includes a bias magnet and two magnetic sensors. The bias magnet produces a magnetic field directed to the gear teeth of the rotating body. When the rotating body rotates, the magnetic field changes with movement between crest and root of the gear teeth. Each magnetic sensor detects the change in the magnetic field and output a sensor signal having a different phase. The rotational position of the rotating body is detected based on the sensor signals.
As described above, at least two magnetic sensors are required to detect a rotational position of a rotating body. Likewise, at least two magnetic sensors are required to detect a rotational direction of the rotating body. Therefore, when the rotation detection sensor is configured to detect both rotational position and direction of the rotating body, the rotation detection sensor needs at least four magnetic sensors. Since the number of the magnetic sensors included in the rotation detection sensor increases, the size of the rotation detection sensor increases accordingly.


A method for marking electrical components, in particular a plurality of series terminals situated one next to another, includes the following steps: attaching at least one unlabeled marking material at a predefined position to at least one component; introducing at least one component into a marking position in a marking device including a laser head; and labeling a marking material using the laser head.

For marking or identifying electrical components, in particular series terminals, different types of marking materials are used. The marking materials are, in particular, marking or identification plates, which are attached at predefined positions to the electrical components. For easy attachment of the marking or identification plates, groove-shaped plug-in recesses are usually formed in the housings of the electrical components or the series terminals, into which the marking plates can be inserted and plugged in. In addition, also marking materials are known, which are designed as adhesive labels or adhesive strips, so that the marking plates can be adhesively bonded onto the electrical components in the respective locations.
To create the marking materials, they are usually initially inserted as an unlabeled printing object, usually in card format, into a corresponding printer, for example an inkjet printer, a thermal transfer printer, a UV printer or a laser printer. The respectively required labeling of the marking material, which usually has a plurality of individual marking plates, is then typically carried out in the printers, so that the marking plates after printing first have to be separated into individual signs or strips. Subsequently, the installation of the individual marking plates on the individual components or series terminals, or on a terminal block made up from a plurality of series terminals situated one next to another, is carried out.
Since in particular series terminals are often installed in greater quantities on carrier rails, the installation of the individual identification plates is considerably time-consuming. For a manual installation, moreover, there is the risk that the identification plates are not correctly installed and plugged into the housing of the series terminals, so that the identification plates can retroactively detach. Moreover, there is the risk that the installer loses the individual identification plates during installation because of their relatively small dimensions.
In order to reduce the time required to install the identification plates or marking plates, automatic devices are known, with the aid of which individual identification plates can be picked-up and inserted into the corresponding plug-in recesses into the series terminals. Such a device for automatically installing identification plates is known from DE 10 2013 012 389 B4. The device, in particular, has a holding device for receiving an identification plate and a moveably mounted assembly stamp, with the aid of which an identification plate received by the holding device can be pressed into a groove-shaped plug-in recess at the series terminal.
Even though such a device for installing individual identification plates can reduce the time and effort for the installation, assigning the individual marking plates to the respective electrical components is associated with a relatively great effort. Additionally, the individual electrical components, in particular in the case of series terminals, are typically each provided with a plurality of identification plates, so that the correct assignment in this instance is also complex and prone to errors. In particular for symmetrically constructed series terminals, a faulty identification of individual connectors can result.

Method for marking electrical components


A process is provided for introduction and diffusion of platinum ions in a slice of silicon material. The slice of silicon is subjected to a succession of thermal steps at high temperature for the formation of at least one semiconductor device. Later processing steps include the opening of contacts and surface metallization. Platinum ions are introduced by ionic implant prior to the metallization step.

1. Field of the Invention
The present invention relates to a process of introduction and diffusion of platinum ions in a slice of silicon containing semiconductor devices.
2. Description of the Prior Art
The need to reduce the lifetime of minority carriers in semiconductor devices derives from different application needs for different types of devices. Device types for which this is a concern include power MOSFETs, fast diodes, insulated gate bipolar transistors (IGBT), bipolar power transistors and thyristors. The object of reducing minority carrier lifetime is to reduce the turn off times of the devices. This reduces energy losses without worsening static device characteristics.
The techniques most commonly used to reduce the minority carrier lifetimes in semiconductor devices include the deposition of gold, the deposition of platinum, and electron radiation.
The deposition of gold is frequently used but it produces two undesired effects. First of all, it causes a considerable increase in leakage current, especially with increasing temperatures. Also, it causes a substantial increase in the resistivity of the silicon of the device.
Although electron radiation does not cause high leadage currents, it does create considerable damage to the Si-SiO.sub.2 interface. This shows up as a lowering of the threshold voltage for MOS devices. The technique can also be sensitive to thermal processes at low temperature (in the range of, for example, 400.degree.-500.degree. C.) such as the processes for attaching a die to its support, normally called die attach.
The deposition of platinum offers several advantages. These include low leakage current, and stability to thermal processes at low temperature (below 700.degree. C.). In addition, compared with the process that uses the deposition of gold, deposition of platinum has lower variations in the resistivity of the resulting silicon.
The process currently in use according to the known art consists in the introduction of platinum into the slice of silicon through a process of deposition on the rear of the slice. This is followed by a process of diffusion at a temperature of approximately 900.degree. C. With this process, a thin layer of silicon oxide is formed during the diffusion. This thin layer of oxide stops further diffusion of the platinum into the slice.
One method for eliminating the layer of silicon oxide provides for the deposition over the surface of the semiconductor of a layer of palladium prior to deposition of the platinum. This has the purpose of facilitating the diffusion of the platinum. As an alternative, platinum silicides suitable for encouraging the diffusion of the platinum into the semiconductor can be formed at the silicon Si-Pt interface. Both of these methods are described in U.S. Pat. No. 4,925,812.
In any case, even when more complicated processes are used, deposition of platinum has substantial limitations. In the first place, the quantity of platinum diffused into the silicon is determined by the thermal diffusion process and by the solid solubility of the platinum in the silicon. In the second place, since the concentration of platinum is equal to the solid solubility, the surface behaves as an infinite source. This causes the distribution of platinum along the length of the slice to be highly uneven. Lastly, the deposition of platinum can be executed only on the rear of the slice of the semiconductor. This does not allow the introduction of platinum in silicon areas bounded by masking.
If it is desired deposit of platinum in well-defined areas on the front of the slice, such deposition is not possible according to the known prior art processes.

Process of introduction and diffusion of platinum ions in a slice of silicon

Consorzio per la Ricerca Sulla Microelettronica Nel Mezzogiorno


A buried-ridge or buried-heterostructure II-VI laser diode. Polycrystalline II-VI semiconductor such as ZnS, ZnSSe, ZnSe or CdS deposited by vacuum evaporation buries the etched ridge.

The present invention relates generally to semiconductor laser diodes. In particular, the present invention is a II-VI laser diode having a buried-ridge waveguide, and a method for fabricating the device.
Laser diodes fabricated from II-VI semiconductor materials have been demonstrated by researchers at 3M in St. Paul, Minn. These devices emit radiation at about 520 nm at room temperature, a wavelength in the blue-green portion of the spectrum. They are disclosed generally in the Haase et al. article Short Wavelength II-VI Laser Diodes, Conference Proceedings for Gallium Arsenide and Related Compounds, 1991 Institute of Physics Conference Series, No. 120, pp. 9-16.
Buried-ridge (buried-heterostructure) laser diodes fabricated from III-V compound semiconductors such as GaAs and AlGaAs and emitting infrared light are well known and widely used. One of the first demonstrations of a buried-ridge III-V laser diode was reported by Tsukada in GaAs-Ga.sub.1-x Al.sub.x As Buried-Heterostructure Injection Lasers. J. Appl. Physics, Vol. 45, p. 4899 (Nov. 1974). These devices are fabricated using an epitaxial "regrowth" procedure by which the initial epitaxial structure is etched and then returned to a crystal growth apparatus to grow the lateral confinement layers (cladding). Epitaxial regrowth typically involves high substrate temperatures to desorb the oxides that form on the device when it is exposed to air after the etching step which forms the ridge.
The Iwano et al. U.S. Pat. No. 4,856,013 discloses a laser diode having an active layer and contact layer formed of III-V semiconductor compounds. The III-V semiconductor is etched to form a rib, and the rib buried in a confinement layer of II-VI semiconductor formed by metal organic chemical vapor deposition (MOCVD). The Niina et al. U.S. Pat. No. 4,607,369 discloses a semiconductor laser buried in a II-VI compound formed by a low temperature deposition process such as MOCVD. However, these epitaxial regrowth techniques are not feasible with II-VI devices since the desorption temperatures required would destroy the conductivity of the previously grown layers.
It is evident that there remains a continuing need for improved II-VI laser diode technology. For widespread commercial viability, the laser diodes must be relatively simple in construction and inexpensive to manufacture. The devices must also be capable of operating at relatively low threshold currents, and providing output beams of good optical quality.


A method of reducing the degradation effects associated with avalanche injection or tunnelling of hot-electrons in a field-effect semiconductor device is disclosed. The method of the present invention includes covering the active regions of the semiconductor device with a protective titanium barrier layer which is deposited directly underneath the ordinary metalization layers used for connecting the devices to bit and word lines within an array. Inclusion of the titanium barrier layer in a flash memory device results in a substantial improvement in the erasetime push-out and reduces excess charge loss normally associated with hot-electron devices.

Hot-electron induced n-channel MOSFET degradation has become a serious concern in present and future VLSI circuits due to the ever-increasing channel electric field in scaled devices. Hot-carrier degradation effects are especially crucial to the reliability of those devices which rely on electrical charge transfer mechanisms such as avalanche injection, channel injection, Fowler-Nordheim tunnelling, hot-electron injection from the substrate, etc. Included in this category of devices are electrically programmable read-only memories (EPROMS) as well as electrically programmable and electrically erasable memories (EEPROMS).
Flash memories (e.g., EEPROMs) are especially sensitive to degradation effects due to the fact that there are a substantial number of hot-electrons generated in each cell during electrical programming and erasing. In these flash memories, hot-electron performance is pushed to extreme limits. For example, during flash memory cycling (i.e., when the device is repeatedly programmed and erased), a significant number of substrate hot-electrons are trapped within the insulating gate oxide layer separating the drain region from the floating gate. The greater the number of cycles that a flash memory device is subjected to, the greater the number of carriers that become trapped in the gate oxide.
Hot-electron degradation effects are often observed in flash memories in two ways. Most noticeably, the erase/programming times for a given memory array are increased far beyond their normal limits. This phenomena is frequently referred to as "erasetime/programtime push-out". This means that as the devices are repeatedly cycled, a greater amount of erase/program time must be allotted for each successive cycle in order to insure that the entire array is completely charged or discharged.
The second way that degradation effects are manifested in a flash memory array is in the form of an excess ("apparent") charge loss which renders the memory devices unreliable. That is, even though the device is initially programmed to an "apparently" correct level, with time that programming level may drop below the limits of reliable operation. This "apparent" charge loss is caused by a shift in the transconductance of the devices after extensive program/erase cycles.
Although the exact mechanism for device degradation is still not known, many studies have indicated that it could be due to hydrogen-related interface state generation. This theory suggests that hydrogen is incorporated into the device structure during various processing steps--including the final annealing step. One source of hydrogen that maybe introduced into the device is the hydrogen-rich passivation layer, which typically comprises some form of oxide or nitride (e.g., oxynitride is commonly used).
Many approaches have been suggested for improving the hot-electron stability in MOS devices. For example, one group of researchers have successfully modified the drain doping profile by grading the drain or employing light-doping levels for the purpose of reducing the channel electric field strength. However, even with the use of these field-reducing structures, hot-electron induced degradation may still persist.
In a paper disclosed in IEDM 88, beginning on page 22, entitled "Improvement of Endurance to Hot-Carrier Degradation by Hydrogen Blocking P-SiO" by S. Yoshida et al., the use of a plasma silicon oxide was proposed as a remedy to the hot-electron problem. The authors believed that a blocking effect against hydrogen may be created by trapping the hydrogen atoms with dangling bonds present in the plasma silicon oxide layer. The plasma silicon oxide was shown to have an excellent capability of trapping and blocking hydrogen.
An alternative technique of performing a final anneal in a nitrogen ambient, rather than in a normal hydrogen ambient, is disclosed in an article by F-C. Hsu et al. entitled "Effective Final Anneal on Hot-Electron Induced MOSFET Degradation", IEEE Electron Device Letters, Vol. EDL-6, No. 7, July, 1985. This article reports that hydrogen content in certain devices can be reduced by performing a final anneal in a nitrogen atmosphere. Thus, hot-electron degradation may be suppressed to a negligible level. A lower hydrogen content leads to lower degradation as reported by Hsu et al. These results strongly support the hydrogen model for hot-electron-induced device degradation.
Another technique which teaches using a long nitrogen anneal is disclosed in an article by Shuo-Tung Chang et al., entitled "Reduced Oxide Charge Trapping in Approved Hot-Electron Reliability and Submicrometer MOS Devices Fabricated by Titanium Salicide Process", IEEE Electron Devices Letters, Vol. 9, No. 5, May, 1988. The nitrogen anneal is discussed in connection with a titanium salicide (self-aligned silicide) process, which is a new technique to reduce source drain resistance in silicon gate devices. The titanium silicide forms the gate electrode of the device. The authors found that titanium sputtering can cause radiation damage at the silicon-oxide interface by generating interface states, thereby degrading transistor performance. Typically, a hydrogen anneal was performed to remove this radiation damage. The authors discovered that using a nitrogen, rather than a hydrogen, anneal results in lower hot-electron degradation.
Even with the use of some of these above mentioned techniques, hot-electron stress in flash memories remains a very serious problem; particularly where the flash memories are used in extended cycle applications. Here they must have the ability to cycle many times without suffering erasetime push-out or excessive charge trapping in the oxide layer.
As will be seen, the present invention provides a method of fabricating flash memory devices which includes depositing a barrier layer of titanium underlying and generally coincident with, normal metalization layers. This titanium barrier layer is not intentionally converted to silicide and actually forms part of the interconnect metalization material. The inclusion of this barrier layer acts to prevent hydrogen present in the passivation layer from interacting with the continuous charge transfer that occurs in the gate oxide region of the memory devices. Using the method of the present invention, the push-out of erasetimes becomes negligible while the reliability of the flash memory devices is substantially enhanced.

Method of reducing hot-electron degradation in semiconductor devices


A semiconductor device fabricating system 1 includes a casing 10, processing units 12, 13 and 14, for carrying out semiconductor device fabricating processes, disposed inside the casing, and platforms 15, 16 and 17 set outside the casing. The platforms are foldable. Spaces required by the platforms can be reduced and the footprint of the semiconductor device fabricating system can be reduced by folding the platforms.

1. Field of the Invention
The present invention relates to a semiconductor device fabricating system.
2. Description of the Related Art
A semiconductor device fabricating device such as disclosed in JP-A 2002-134588, which performs various processes including those for processing a wafer by cleaning, drying and etching, has been used for fabricating a semiconductor device. A conventional semiconductor device fabricating system includes a carrier handling unit for receiving and sending out a carrier containing plural wafers, a wafer carrying unit for carrying the wafers contained in the carrier, and a wafer processing unit for processing the wafers by various processes including cleaning process, drying process, and etching process. The carrier handling unit is disposed in one end area in a box-shaped casing, the wafer carrying unit is disposed behind the carrier handling unit in the casing, and the processing unit is disposed behind the wafer carrying unit in the casing. Stationary platforms are disposed beside the casing. The platforms are used for maintenance work for inspecting and cleaning the processing unit and changing parts of the processing unit and for inspecting the processing condition of the wafer processing unit.
Therefore, a space for installing the stationary platforms is needed in addition to a space for the semiconductor device fabricating system when the semiconductor device fabricating system is installed in a plant. Thus the platforms increase the footprint of the semiconductor device fabricating system. The platforms disposed beside the semiconductor device fabricating system are used mostly for maintenance work and inspection work and are rarely used while the semiconductor device fabricating system is in a normal operation for accomplishing those processes. That is to say, although the platforms are not used frequently, the platforms increase the footprint of the semiconductor device fabricating system. Thus, in some cases, the installation of the conventional semiconductor device fabricating system is subject to restrictions on layout.


An antenna which can be operated in a number of frequency bands and has at least one part which encloses an area and at least one part which does not enclose an area, with the at least two parts including a single conductor part being connected in series with one another, and the at least two parts interacting with one another in such a manner that the antenna has at least two resonant frequencies in a definable position, and with each at the same time having a wide bandwidth.

The present invention relates to an antenna which can be operated in a number of frequency bands, and which is preferably suitable for use in frequency bands for different Standards of mobile radio networks.
In recent years, mobile radio networks have been developed to different Standards, which operate in different frequency bands. For example, the GSM Standard mobile radio network operates in the region around 900 MHz, the PCN Standard mobile radio network operates in the region around 1800 MHz, and the PCS Standard mobile radio network operates in the region around 1900 MHz. In this case, it should be noted that the frequency bands for the PCN and PCS Standards overlap one another.
It is, accordingly, desirable to produce mobile radio telephones or similar devices which can be operated, in a number of different frequency bands, that is, which are able to work with different mobile radio network Standards. This requires the mobile radio telephones to have one or more antennas which also need to have different resonant frequencies. The resonant frequencies are, in this case, those for the respective frequency bands of the desired mobile radio networks. The reflection factor at these resonant frequencies must be as low as possible, and an adequate bandwidth also must be available to allow the mobile radio telephone to be operated in the respective frequency bands of the mobile radio networks to the various Standards.
A further major factor for the design of antennas for mobile radio networks is that the dimensions are subject to severe limitations, for design reasons.
In previous antenna structures, which include a number of antennas, two helical antennas or other shapes such as meandering structures have been used, for example, for covering two different frequency bands. However, these solution approaches require more space than, for example, a simple helical antenna and/or their performance is poorer.
An antenna structure whose essential structure is illustrated schematically in FIG. 5 is known from EP-A-747990. This antenna structure has a first antenna element 10 and a second antenna element 20. The first antenna element 10 has a helical shape, and the second antenna element 20 is in the form of a straight rod or conductor. The two antenna elements 10 and 20 are connected to one another at a common feedpoint 30, and at least part of the second antenna element 20 is arranged inside the first antenna element 10.
In the antenna structure shown in FIG. 5, the first and second antenna elements 10 and 20, respectively, have different resonant frequencies to one another. Thus, the antenna structure shown in FIG. 5 can be operated in at least two frequency bands, for example, two frequency bands of mobile radio networks.
However, the already described antenna structure has considerable disadvantages. The mechanical design of the antenna structure is complex since the antenna structure includes a first and a second antenna element 10 and 20, respectively, with at least part of the second antenna element 20 being arranged inside the first antenna element 10. For this reason, a large amount of effort has to be accepted to manufacture the antenna structure.
Furthermore, the two antenna elements 10 and 20 are located physically close to one another which can lead to problems, such as short-circuit. The antenna structure also has a narrow bandwidth in the region of one of the resonant frequencies, which can lead to problems during operation in certain mobile radio networks.
Finally, the antenna structure requires a matching network in order to achieve a matching to, normally, 50xcexa9. Such a matching network causes losses in the system, however, owing to the components required for this network.
The present invention has been brought about as a result of the problems with the prior art which have been mentioned above, and its object, accordingly, is to provide an antenna which can be operated in a number of frequency bands, has a simple and low-cost structure, and can be produced easily.
According to the present invention, therefore an antenna which can be operated in a number of frequency bands has at least one part which encloses an area and at least one part which does not enclose an area. The at least two parts are composed of a single conductor part and are connected in series with one another. Furthermore, the at least two parts interact with one another in such a manner that the antenna has at least two resonant frequencies at a definable position, and with each at the same time having a wide bandwidth.
Since the two parts are composed of a single conductor part, only a single production process is required to manufacture the antenna, and an antenna with a simple and low-cost structure can be achieved.
According to embodiment of the present invention, the antenna operates with a broad bandwidth close to a first resonant frequency in such a manner that it can be used in a first intended frequency band and operates with a wide bandwidth close to a second resonant frequency in such a manner that it can be used in two further intended frequency bands, and preferably has a characteristic impedance of 50xcexa9 in the intended frequency bands.
The resonant frequencies of the antenna likewise can be defined, while each at the same time having a wide bandwidth, in such a manner that the antenna can be used in the frequency bands of a number of mobile radio, for example, the GSM, PCN and PCS Standards.
Additional features and advantages of the present invention are described in, and will be apparent from, the following Detailed Description of the Preferred Embodiments and the Drawings.

Antenna which can be operated in a number of frequency bands


A triple host vector is described which is capable of expressing an inserted protein coding DNA sequence in any of three distinct host systems. The vector includes three promoters, one each for vertebrate, bacterial and insect host cells, so that the protein coding sequence can be cloned into the vector once and the vector can be used to express protein in all three types of host cells. The arrangement and selection of the promoters contributes to expression characteristics in all three host systems that is comparable to single host expression vectors.

In the practice of modem biotechnology it has become common practice to create artificial gene constructions which are capable of expressing a foreign protein in a host which normally does not produce that protein. The process of producing a protein from a gene in a host is referred to as protein expression.
Interest in expressing proteins in foreign hosts has led to the development of a market in pieces of DNA known as expression vectors. Expression vectors, often but not invariably sold in the form of circular pieces of DNA known as plasmids, contain all of the genetic elements on them to express a protein coding sequence inserted into a defined location within the expression vector. Typically one would create the coding sequence for a protein that one wants to express and then insert that coding sequence into a defined location in the expression vector. The expression vector would already contain within it a promoter adapted for use in the host for which the expression vector is defined and may also include suitable downstream transcription terminators or polyadenylation sequences sufficient to terminate transcription, a necessary requirement in a eukaryotic, but not a prokaryotic host. Such expression vectors often would also have a selectable marker gene for one or more forms of antibiotic resistance so that the bacterial host containing the expression vector can readily be identified.
Different categories of host organisms require different promoters. For example, prokaryotic promoters such as those functional to cause gene expression in bacteria, are almost invariably non-functional in eukaryotic organisms such as vertebrate or plant cells or yeast. Even among eukaryotic organisms, most plant promoters do not work in animal cells and most animal promoters do not work in plant cells. Accordingly it is typically the case that an expression vector is designed for a specific host or class of hosts and has promoters and other genetic elements specifically designed for that specific host.
One prior vector is known that can be used in two hosts. The pDual vector from Stratagene includes promoters suitable for both mammalian cell expression and bacterial expression. No prior vector is known capable of operation in more than two categories of hosts.
The present invention is summarized in that a multiple host expression vector has built within it a facility for expression of a inserted protein coding sequence in bacterial cells, vertebrate cells, and in baculovirus infected insect cells. This permits the same expression vector to be used in bacterial, insect, or vertebrate-cells to produce a protein of interest.
The vector of the present invention advantageously has diverse promoters in the orientation of vertebrate, then bacterial, then baculovirus, since then the bacterial and baculovirus promoters can be incorporated into 5xe2x80x2 untranslated mRNA that does not affect efficient expression of an inserted gene sequence in vertebrate-cells.
The present invention is also summarized in that the p10 baculovirus promoter is used in such a multiple host expression vector, the p10 baculovirus promoter permitting high expression of inserted protein coding sequences in baculovirus infected insect cells without adversely effecting the functioning of other promoters contained within the vector.
Other objects, advantages and features of the present invention will become apparent from the following specification when taken in conjunction with the accompanying drawings.


The present invention relates to a method and a device for detecting mercury in a sample solution, the mercury being contained in the sample solution in cationic form and as an organic compound, by means of a detection device comprising an atomic spectroscope provided with a measuring cell which is suitable for detecting mercury gas, a noble-metal concentrator for concentrating the mercury and a control unit, the mercury being converted into the gas phase and being adapted to be concentrated by means of the noble-metal concentrator. The method according to the present invention is characterized in that the control unit controls the supply of the mercury gas to the measuring cell in such a way that, in addition to the measurement of the concentrated mercury, mercury gas of the same sample, which has not been subjected to the concentration step, is introduced in the measuring cell for the purpose of measurement. A device according to the present invention is characterized in that the supply line has provided therein a controllable valve element, which communicates with the control unit, in such a way that, under the influence of the control unit, the mercury gas of the same sample solution can selectively be introduced from the concentrator or directly from the gas phase area into the measuring cell. A further device according to the present invention is characterized in that it comprises a second measuring cell which is adapted to have supplied thereto mercury gas directly from the gas phase area under the control of the control unit.

The present invention relates to a method and a device for detecting mercury in a sample solution containing the mercury in cationic form and as an organic compound, by means of a detection device comprising an atomic spectroscope provided with a measuring cell which is suitable for detecting mercury gas, a noble-metal concentrator for concentrating the mercury and a control unit, the mercury being converted into the gas phase and being adapted to be concentrated by means of the noble-metal concentrator.
Mercury is one of the elements having a toxic effect on human beings and animals in a very low concentration. It is therefore necessary to detect mercury concentrations even in very small doses. In addition to the total mercury concentration, especially also the chemical species in which the mercury appears in the sample to be tested are of importance. In this respect, methyl mercury is regarded as one of the most frequently appearing species, having, in addition, an extremely toxic effect.
In conventional methods and devices mercury is detected e.g. by means of the optical atomic spectrometry in the form of atomic absorption spectrometry, atomic fluorescence spectrometry, atomic emission spectrometry or mass spectrometry. In the case of these methods the mercury contained in cationic form or as an organomercury compound in a solution to be tested is determined e.g. by the so-called cold-vapour technique. For this purpose, the mercury contained in the solution is converted by reaction into an atomic gas or vapour, whereupon it is possible to carry out mercury detection by one of the above-mentioned methods in the field of measurement technology.
In order to increase the power of detection, other components in the solution can be eliminated. The sensitivity in the detection process can be increased still further by conducting the mercury gas produced first over a net of noble-metal alloys and by concentrating it then by amalgamation. Subsequently, the mercury adhering to the net is released in the form of mercury gas by heating the net, whereupon it is subjected to the measurement.
By means of these methods it is possible to determine the total mercury content; for a separate determination of e.g. methyl mercury, a previous separation into species will, however, be necessary. This separation normally takes place in a chromatographic method or via cooled condensation traps. This, however, necessitates a separation unit and a detection unit as well as essential additional efforts for preparing the sample so as to carry out this separate determination of the methyl mercury content and of the total mercury content.
Furthermore, a method is imaginable which utilizes the fact that cationic mercury can be converted into the vapour or gas phase with mild reducing agents, whereas certain organomercury compounds can only be converted into the vapour or gas phase with comparatively strong reducing agents. It is true that this method offers an advantage in comparison with the above-mentioned method as far as the simplicity of sample preparation is concerned, but for successively determining the total mercury content and the methyl mercury content two separate reaction units have to be used, since the two reducing agents mutually influence one another. In addition, it turns out in practice that, due to the use of two reducing agents and of two reaction units, the experimental parameters cannot be controlled in a way which permits the mercury content to be determined with the necessary accuracy and reproducibility.
It is therefore an object of the present invention to provide a method and a device which permit by means of a simple treatment of the sample a reliable determination of the total mercury content and of the mercury content in the form of an organic compound.
According to the present invention, this object is achieved by providing a method of the type mentioned at the beginning in the case of which the control unit controls the supply of the mercury gas to the measuring cell in such a way that, in addition to the measurement of the concentrated mercury, mercury gas of the same sample, which has not been subjected to the concentration step, is introduced in the measuring cell for the purpose of measurement.
The present invention is based on the inventors"" finding that when the mercury is converted into the gas phase, e.g. by reduction with sodium hydridoborate, this has not only the effect that cationic mercury is converted into the gas phase, but also that organomercury, such as methyl mercury, is also released as a gaseous compound. The gaseous mercury developing from the cationic mercury can directly be detected in a measuring cell. The gaseous compound developing from the methyl mercury does, however, not cause any specific atomic absorption or atomic fluorescence during this measurement. It follows that, even if the sample solution is treated such that not only gaseous mercury develops from the cationic or inorganic mercury but that a gaseous compound of the organomercury (methyl mercury) develops as well, a measurement in the measuring cell will still exclusively indicate the content of cationic mercury in the sample.
The gaseous compounds produced can be collected on the concentrator, e.g. a noble-metal net or sand coated with noble metal, and amalgamated. Under the catalytic influence of the noble metal, the organic gaseous mercury compounds will decompose. When the mercury has been released from the concentrator and subsequently introduced in the measuring cell, the sum of inorganic (cationic) and organic mercury will therefore be detected. This permits a determination of the content of organic mercury and of the total mercury content by means of two successive measurement steps; a simple sample preparation will suffice for this purpose.
According to an advantageous embodiment, the mercury contained in the sample solution is converted into the gas phase by reduction. Hence, known devices can be used for reducing the sample in the method according to the present invention, whereby the expenditure for the devices required will be reduced.
According to an advantageous further development of the present invention, the sample containing the mercury is reduced with sodium hydridoborate.
In the course of the experiments carried out by the inventors, it turned out that especially the gaseous mercury compounds obtained by a reduction with sodium hydridoborate permit a reliable determination of the inorganic or cationic as well as of the total mercury content.
According to another advantageous further development, the mercury gas will be introduced into the measuring cell without having been subjected to the concentration step, if the control unit has detected that a predefined threshold value has been exceeded in the preceding measurement of the concentrated mercury gas supplied from the concentrator.
Due to the fact that a threshold value is predetermined and that this threshold value is automatically supervised, a swift measurement is guaranteed, since only the second measurement step for determining the inorganic mercury content will be carried out, if an admissible total mercury content has been exceeded.
According to an advantageous embodiment, the control unit determines an overall result on the basis of the measurement results of the two measurements.
In this way it is, on the one hand, possible to automatically determine the total mercury content as well as the amount of inorganic mercury in a sample, and, on the other hand, the content of organic mercury compounds can be determined automatically with due regard to the two measurement results.
The method can be used in an advantageous manner when the organic mercury compound contains methyl mercury.
The method according to the present invention thus permits a simple preparation of a sample containing mercury and the simultaneous determination of the amount of extremely toxic methyl mercury as well as of the total mercury content.
The present invention also provides a device for detecting mercury in a solution, comprising a gas phase area in which the mercury in the solution can be converted into the gas phase, a concentrator for concentrating the mercury, an atomic spectroscope provided with a measuring cell which is implemented such that it is suitable for detecting mercury, a supply line which serves to introduce the mercury gas into the measuring cell, and a control unit communicating with the measuring cell, said device being characterized in that the supply line has provided therein a controllable valve element, which communicates with the control unit, in such a way that, in dependence upon said control unit, the mercury gas of the same sample solution can be introduced from the gas phase area into the measuring cell selectively with or without the concentrator.
It follows that this device according to the present invention is particularly suitable for executing the method according to the present invention, since the valve element permits a controlled supply of a sample gas selectively from the concentrator or from the gas phase area.
The present invention additionally relates to a device for detecting mercury in a solution, comprising a gas phase area in which the mercury in the solution can be converted into the gas phase, a concentrator for concentrating the mercury, an atomic spectroscope provided with a first measuring cell which is implemented such that it is suitable for detecting mercury gas from the concentrator, a supply line which serves to introduce the mercury gas into the first measuring cell, and a control unit communicating with the first measuring cell, said device being characterized by the following features according to the present invention: that the device comprises a second measuring cell which communicates with the control unit and which, under the control of said control unit, is adapted to have supplied thereto mercury gas directly from the gas phase area excluding the concentrator.
The provision of a second measuring cell, which is adapted to have supplied thereto mercury gas directly from the gas phase area, is particularly suitable for the above-mentioned method according to the present invention; an increased measurement speed can be achieved in view of the fact that reference and calibration measurements, respectively, can be carried out in the second measuring cell e.g. during the measurement taking place in the first measuring cell so that a high measurement accuracy can still be achieved in the case of high measurement speeds.
According to an advantageous embodiment, the gas phase area comprises a reduction area in which the mercury can be converted into the gas phase by reduction.
This permits the use of known reduction devices in the device according to the present invention, whereby an economy-priced overall solution will be obtained.
According to an advantageous embodiment, the control unit is implemented such that it is adapted to form on the basis of the measurement of the mercury content of the gas supplied from the concentrator and on the basis of the measurement of the amount of mercury supplied from the gas phase area a total value resulting from both measurements.
When this total value resulting from both measurement processes is being determined, the different pretreatments of the mercury gas, when said mercury gas is fed from the concentrator and directly from the gas phase area, respectively, are taken into consideration. Furthermore, the control unit can constantly cause the execution of a reference measurement in the measuring cell or measuring cells so as to incorporate a shift of experimental parameters in the evaluation and combination of the individual measurements.
A further embodiment is obtained in combination with the atomic absorption spectrometer device disclosed in DE 44 11 441 in which the measuring cell comprises at least two chambers which are adapted to be connected to one another and through which a light beam can be passed, the light absorption paths of these chambers being in a certain ratio to each other.
On the basis of the subdivision of the measuring cell into at least two connectable, separate chambers it is possible to provide different light absorption paths for the sample substance which is to be examined with regard to its mercury content. The chamber having the longer light absorption path may serve to detect the mercury which is directly supplied from the gas phase area into the measuring cell, so as to achieve a higher sensitivity in comparison with the sample supplied from the concentrator into the measuring cell.
Furthermore, it will also be advantageous when, by means of a division into separate chambers or by a suitable selection of the length and, consequently, of the absorption length, the second measuring cell is adapted to the behaviour of the first measuring cell into which the mercury is fed from the concentrator. This measure permits a substantial increase in the accuracy of the measurement and of the total result.
According to an advantageous embodiment, the chambers in the measuring cells are adapted to be connected by switching valves which are controllable by the control unit. An automatic light absorption length of the spectrometer, which is adapted to the respective measurement conditions, can be adjusted in this way.
Further advantageous embodiments are disclosed in the subclaims.

PerkinElmer Bodenseewerk Zweigniederlassung der Berthold GmbH and Co. KG


A fluid charging system for charging each of a succession of components with a weight of a fluid, each of the components being charged with a respective selected fluid weight selected from a plurality of fluid weights, the fluid charging system including a scale for weighing each of the components and for generating weight signals indicative of the weight of each of the components, an identification mechanism for generating identification signals identifying each of the components, a pumping system for charging each of the components with the respective selected fluid weight by delivering the respective selected fluid weights to the components, and a digital processing mechanism for receiving the weight signals and the identification signals, for determining the respective selected fluid weight for each of the components from the plurality of fluid weights, and for actuating the pumping system to thereby cause the pumping system to deliver the respective selected fluid weights to the components.

1. Field of the Invention
The present invention relates to the field of filling apparatuses, even more particularly to fluid charging apparatuses that dispense predetermined weights of a fluid, most particularly a lubricating fluid, such as, for example, oil and the like.
2. Description of the Related Art
U.S. Pat. No. 5,133,391 relates to a method and arrangement for accurately injecting a preset proportion of an additive into an oil product when the oil product is being loaded into an oil tank truck at a truck farm or the like
U.S. Pat. No. 4,966,206 relates to a device for filling a container with a gaseous fuel such as natural gas that adjusts the filling pressure of the gaseous fuel to the local ambient temperature.
U.S. Pat. No. 4,840,064 relates to a liquid volume monitoring apparatus and method, particularly advantageous for determining the volume of liquid in a liquid reservoir of an integrated drive generator of an aircraft engine, wherein the ullage volume of a container having an inflow and an outflow is determined by interrupting one of the inflow and the outflow and detecting the pressure of the gas in the ullage volume, from which a microprocessor calculates the volume of liquid in the container during the interruption from the detected change in pressure of the gas.


A reflector (3) of a motor vehicle headlight is coupled with a housing (1) by an adjustment device (4) with which it is pivoted about an axis (10). The adjustment device substantially comprises an adjusting pin (12) rotatably mounted in an opening in the housing with an end portion thereof extending outwardly from the housing opening, forming a hand knob (23) thereon for rotating the pin. An indicating device of the motor-vehicle headlight substantially comprises a toothed gear (20) with a scale-like indicator thereon and a pinion gear (16) which is formed on the hand-knob portion of the adjusting threaded pin. The toothed gear is mounted on an axle (25) extending outwardly from the housing and rotates freely in a position in which it interengages with the pinion gear. The toothed gear lies flatly on an outer surface (17) of the housing. The toothed gear has a central opening (24) and an off-center opening (27) adjacent the central opening. The openings (24, 27) are in communication with one another through a stricture ( 28) which is narrower than a cross section of the axle and of which, at least on one side, is radially flexible because of an adjacent cavity (30) in the toothed gear. Thus, the toothed gear can be moved between a first position in which the toothed gear interengages with the pinion and in a second position in which it is removed from this interengagement.

This invention concerns an adjustment system, or apparatus, for a reflector of a motor-vehicle headlight of a type having: a threaded adjusting pin which is rotatably mounted in an opening of a fixed housing containing the reflector which has a hand knob on an end portion thereof for rotating it while it is coupled to the reflector at an opposite end portion thereof, so that the reflector is pivoted about an axis by rotating the adjusting pin; and an indicating device for indicating the position of the reflector comprising essentially a toothed gear with a scale-like indicator thereon and a pinion gear mounted on the adjusting threaded pin for interengaging with the toothed gear, the toothed gear being loosely mounted for rotation on an axle extending outwardly from the housing with the axle extending through a central opening of the toothed gear and having a radial lug at its free end for engaging an outwardly facing side of the toothed gear, and with the toothed gear being movable from a position in which is doesn't engage the pinion to a position in which it does engage the pinion, the toothed gear including a locking device for securing it against such movement. Such an adjusting system for a reflector of a motor vehicle headlight is disclosed in German Offerlegungsschrift DE 40 13 893 A1. In the device of this patent a housing for receiving a reflector is manufactured of resinous plastic to have a pot shape. The pot-shaped housing is closed at its front side by a light-transmissive shield or lens. The reflector is supported within the housing by two adjusting devices and a fixed holding device. With the adjusting devices the reflector can be pivoted about a horizontal axis and about a vertical axis. The horizontal axis is defined by an adjustable position of an adjusting device and a fixed position of the holding device while the vertical axis is defined by the fixed position of the holding device and an adjustable position of the other adjusting device. The adjusting device which pivots the reflector about the vertical axis has a scale-like indicating device with which, by a simple visual inspection, it can be determined if the reflector is properly adjusted with regard to its horizontal pivoting; that is, it is possible by means of a visual inspection to determine if the optical axis of the reflector extends parallel to a vertical middle plane of a motor vehicle. The adjusting pin of the adjusting device for horizontal pivoting of the reflector is rotatably mounted in an opening at an edge of a floor of the pot-shaped housing. An end portion of the adjusting pin nearest the reflector is a threaded shaft which engages a nut pivotally mounted on a backside of the reflector, the nut being slidably guided for movement on an upper sidewall of the housing. An end portion of the adjusting pin or bolt, which extends out of the housing is knurled on its outer surface. A manipulation knob is shoved onto the knurled portion in press-fit which serves as a hand knob to rotate the adjusting pin. An opening of the housing which serves as a rotational mount for the adjusting pin is sealed by a ring seal which lies against an interior edge area of the housing defining the opening. A pinion gear of the indicating device is arranged on a side of the manipulation knob facing away from the housing and has a substantially smaller cross-section than the manipulation knob. A toothed gear whose teeth interengage teeth of the pinion gear is bowl-shaped with its teeth being about its outwardly directed peripheral edge. An inner side of the bowl shaped toothed gear is directed toward a front of the headlight and on the floor of the bowl-shaped gear there is a central inverted hub in which there is a central opening of the toothed gear. The axle which extends through the central opening of the toothed gear is a separate part and its length axis extends parallel to a length axis of the adjusting pin. An end portion of the axle extending toward a front side has a knurled outer surface which is pressed into an opening in a flange of the housing extending radially from the housing. An end portion of the axle directed toward a back of the headlight has at its free end a radial head which defines a circumferential edge surrounding the axle whose outer diameter is slightly smaller than an inner diameter of the inverted hub which is in the floor of the bowl-shaped toothed gear. In a position of the toothed gear in which it interengages with the pinion gear, the circumferential edge, or head, of the axle is spaced from a base of the inverted hub and spring arms mounted outside the base of the inverted hub engage in a ring groove about the axle at a level of the manipulation knob. A scale of the indicating device is on a facing side of the toothed gear directed toward the rear of the headlight to cooperate with a pointer serving as a measuring mark, which is a separate part and which is additionally attached to the housing. In order to move the toothed gear to its position in which it is not interengaged with the pinion gear, it can be moved axially toward the rear of the headlight until the head defining the radially outwardly protruding surrounding edge of the axle engages on the base of the central depression, or inverted hub, of the toothed gear. When this is done, the spring engaging arms in the surrounding groove of the axle glide out of the ringed groove to lie on a main outer surface of the axle. By axially moving the toothed gear between these two positions the toothed gear can be set to a zero value of the scale as indicated by the pointer after the reflector of the headlight is exactly horizontally adjusted. It is a disadvantage in this known adjustment system for a reflector of a motor-vehicle headlight that the thin-wall toothed gear is spaced from a housing rear side and, when viewed along its axis, extends beyond sidewalls of the pot-shaped housing whereby the headlight can be easily and quickly damaged when it is mounted on a motor vehicle body. Further, the toothed gear must be mounted onto an axle which is a separate part. When the toothed gear is dismounted, the axle must be pulled out of the opening of the outwardly extending flange of the housing by application of great force. Pulling out the axle requires an assisting tool and the flange of the housing can be broken when it is pulled out. Similarly, when the toothed gear is mounted the axle must be pressed with great force in the opening of the flange of the housing. When this is done, one must be careful that the axle is pressed only so far into the flange of the housing that the teeth of the toothed gear come into interengagement with the pinion gear of the adjusting pin. Such a mounting and a dismounting of the toothed gear is quite inconvenient and time intensive. Further, because the toothed gear is spaced from the outer surface of the housing, it can be inadvertently moved to the position in which it is no longer in interengagement with the pinion gear. The toothed gear also cannot be moved closer to the outer surface of the housing because the large manipulation knob is arranged between it and the housing as a hand knob to rotate the adjusting pin. The pointer which provides the measuring mark is not only a separate part but also is spaced from the outer surface of the housing and can therefore be easily broken.
It is an object of the invention to provide an adjustment system of the type mentioned above for a reflector of a motor vehicle headlight whose toothed gear has an indicating device and whose axle cannot be easily damaged when it is stored, transported and mounted in a motor-vehicle-body opening and whose toothed gear can also reliably function while having a flat configuration across its width.
Further, it is an object of the invention to provide such an adjustment system whose toothed gear can be easily mounted and dismounted.

Adjustment system for a motor vehicle headlight reflector


The invention provides a sensor system, mote and a motes-system. The sensor system is configured for being contained in a container having a maximum outer dimension less than 10 millimeter and for sensing at least one environmental parameter (T, P, pH, ρ). The sensor system includes at least one sensor configured for measuring the at least one environmental parameter and for generating a sensed value (xT, xP). The sensor system includes a storage element and a timer in which the at least one sensor is configured to measuring the at least one environmental parameter at each time triggers (t1, t2, . . . ) from the timer and for storing a sensed value (xT, xP). The sensor system further includes an energy storage comprising a chargeable capacitor being chargeable via electro-magnetic radiation of a predefined frequency, and wherein the sensor system is configured to initiate a sequence of sensed values when the energy storage is charged or is being charged.

Sensors for sensing an environmental parameter are well known and used throughout our current environment. Only one of the many examples used in today's world may, for example, be a temperature sensor which may, for example, be applied in a car for providing temperature information to the driver of the car or to the on-board computer of the car. Such a sensor draws its power from the overall power system of the car and uses the on-board wiring to provide the sensed value to the display of the car or to the on-board computer. However, when sensing the environmental parameters in a remote location, the requirements to the sensor system are quite different.
Sensor systems having such requirements are, for example, used in a sensor mote. A sensor mote typically refers to a relatively small sensor with its own energy storage. Also typically the sensor mote is part of a wireless network via which the sensed environmental parameter is communicated to a remote computer. A motes-system is a plurality of sensor motes which together form a plurality of sensors for sensing the environmental parameter. Such motes-systems have been used in many diverse applications, from earthquake measurements to warfare.
Such known motes typically comprises a controller, transceiver, power source and one or more sensors. One example of environmental monitoring can be found in the NASA sensor web. This network comprises spatially distributed sensors that wirelessly communicate with each other. In this network, every mote sends out collected data to every other mote, so substantially every mote knows what is happening in the network. Alternatively, sensor networks may be configured to use GPS communication and/or may be configured to handle "Big" data sets.
Using such known sensor networks for environmental mapping or monitoring, the position of the individual motes should be known which requires extensive communication with the outside world, for example, via a Global Positioning System (further also indicated as GPS). However, in some remote environments, such as, for example, oil wells or sewer systems in cities, the GPS signal does not reach the individual motes and other means of measuring the environment parameter have to be found.

Sensor system, mote and a motes-system for sensing an environmental parameter


A processor capable of performing a two-dimensional transform on high speed serial sampled analog raster scanned data and outputing the results in a parallel fashion so as to provide for a data rate reduction. The processor utilizes a charge coupled device (CCD), a matrix multiplier to perform a one-dimensional transform on data samples from a serial to parallel converter. The data is switched into a set of matrix multipliers which perform another transformation whose results are summed in an accumulator to yield the desired two-dimensional transformed coefficients.

1. Field of the Invention
This invention relates generally to any processing system requiring a two-dimensional transformation of source data, and more specifically to video bandwidth compression systems which use transform and coding techniques to minimize the number of coding symbols required to describe an image.
2. Description of Prior Art
Two-dimensional transforms are ordinarily generated either optically or through the use of a digital computer. Both methods suffer from severe limitations in many signal processing applications. A general purpose digital computer large enough to perform two-dimensional transforms in real time is heavy, expensive, and consumes an excessive amount of power for many airborne transform encoder applications. Coherent optical two-dimensional transform implementations interface poorly with electronic systems and the aircraft environment. Another approach to performing a two-dimensional transformation consists of performing a row by row one-dimensional transform with serial access hardware, storing the one-dimensional transform coefficients in place, and then performing a column by column one-dimensional transform. A block diagram of a row-then-colum transform processor is shown in FIG. 1. Basically, in performing an N by N transform, each row is divided into blocks of N pixels or resolution elements. A one-dimensional N-point transform is applied to each horizontal block and the transform coefficients are stored in the memory. Since N rows must be transformed and stored before the one-dimensional transform can be applied in the vertical direction, this intermediate memory size must be N lines. As indicated in FIG. 1, a redundant N-line memory is required so that while the transform is applied in the vertical direction the transform coefficients for the next N rows can be stored.
The primary shortcomings of this approach is that the processor architecture does not allow for a reduction in sample rate which, depending upon the resolution requirements of the system can be high. For instance, for a state of the art processor, the sample rate could be as high as 9.7 million samples/second.
Such a high speed requirement causes implementation problems in two areas. First of all, a "corner turning" operation is required in order to organize the row transformed coefficients before the transform can be applied in the vertical direction. This operation becomes difficult to implement at the higher speeds. More significant, though, is the high speed A/D converter requirement. State of the art A/D converters operating at 10 MHz and 8 bits are either large, expensive, or not readily available. When this is combined with low power requirements, the row-then-column implementation of the two-dimensional cosine transform does not become practical for most low cost airborne encoder applications.
Accordingly, it is an object of the present invention to provide a two-dimensional transform processor which is organized to accept high speed serial sampled analog input data and to output the results in a parallel fashion resulting in a data rate reduction for subsequent processing.
A further object is to accomplish two-dimensional transform processing at a fraction of the cost, size, weight and power required by other two-dimensional transform techniques.


A method of manufacturing a cellulosic sheet having at least one of hydrophobic and oleophobic properties comprises the steps of depositing a stock of cellulosic fibers onto at least one forming fabric at an impingement zone and forming a web therefrom in a formation process; combining a water-based composition comprising an adhesion promoter, an organic nanoparticulate polymer and a fluorocarbon with the web at a preselected combination stage prior to a heating stage at which the web is subjected to a temperature exceeding 60° C.; and heat-curing the composition with the web during a drying process. A water-based composition for imparting at least one of hydrophobic and oleophobic properties to a cellulosic sheet during manufacture comprises an adhesion promoter, an organic nanoparticulate polymer and a fluorocarbon. A cellulosic sheet or layer thereof has at least one of hydrophobic and oleophobic properties. Improved resistance of cellulosic sheets to oil or water is obtained.

Coating treatments intended for application to nonwoven sheet type products, such as paper and related cellulose based products, to provide a physical barrier so as to render them either, or both, hydrophobic and oleophobic, are known. See for example U.S. Pat. No. 5,330,622 to Honnorat et al. Others are known and used.
Similarly, coating treatments to papermaking machine clothing for various purposes are also known, in particular for the provision of a barrier layer to improve the ability of the fabrics to resist staining, adhesion of contaminants, and to improve phase separation, and to increase hydrophobicity.
Recently, for such treatments, use has been made of sol-gel coatings, which are defined as coatings produced by the sol-gel process of glassmaking, in which glass is formed at low temperatures from suitable compounds by chemical polymerization in a liquid phase; a gel is formed from which glass may be derived by the successive elimination of interstitial liquid and the collapse of the resulting solid residue by sintering.
Such sol-gel coatings have been used to form a barrier layer on, amongst other things, woven and nonwoven textile products so as to improve their ability to resist staining and the adhesion of contaminants. Further, it is known to treat papermaking fabrics such as through air dryer (TAD) fabrics with sol-gel coatings so as to increase their hydrophobicity. The coating causes less water to be carried into the TAD section by the fabric and thus the amount of energy used to evaporate water from the sheet is reduced because it is used to dry the sheet, rather than both the sheet and the supporting fabric.
For phase separation devices such as filter cloths, it is now known that organically modified ceramics, known as "ormocers", can advantageously be used. For example, U.S. Pat. No. 5,980,986 to Sayers et al. claims a method of using at least one ormocer as a coating; U.S. Pat. No. 5,932,291 to Sayers et al. claims a method of using the ormocer in papermachine clothing; and U.S. Pat. No. 5,989,651 to Sayers et al. claims a method of using at least one ormocer as a coating to facilitate phase separation by incorporating the ormocer into the polymer melt prior to extrusion, and coating the phase separation apparatus with the extruded polymer melt.
These three related patents refer to the use of an ormocer which contains a perfluorinated material. Those of skill in the art would recognize that these ormocers are organic/inorganic hybrid polymers with a fluorinated material which consist of:                1. a cross-linkable organosilicon (e.g. with epoxy or methacryl groups; see col. 1, lines 50-60 of U.S. Pat. No. 5,932,291), a substance which produces good adhesion with the background (in this case, a fabric) and,        2. an organosilicon with a perfluorinated side chain.
Thus the ormocer consists of a polar and a hydrophobic component and contains ceramic microparticles.
None of the three related patents in this group indicates whether the chemicals used in the coating containing the ormocers are water-based or at least partially solvent-based. However, as at the time of the priority date of these patents (Nov. 16, 1993 and Feb. 1, 1994), only coatings containing solvents were known, the disclosures of these patents can only be regarded as referable to the use of at least partially solvent-based coatings. For imparting desired physical properties to cellulosic products for their specific intended uses, it is also known to introduce optional additives to the stock, prior to its delivery by means of a headbox to an impingement point on a forming fabric. Such additives include fillers and other materials to improve solids retention or opacity. For example, U.S. Pat. No. 5,147,507 to Gill teaches the use of anionic and cationic polymers to reduce the required quantities of a sizing agent and to improve the qualities of filler retention, drainage and opacity; and U.S. Pat. No. 4,925,530 to Sinclair et al. teaches the use of additives for obtaining improved retention. Further, U.S. Pat. No. 6,551,457 to Westman et al. teaches the use of additives to alleviate problems of delamination in processes involving the use of an impulse press unit; in such additives, the anionic polymers can be organic or inorganic, and an organic polymer can include a hydrophobic group.
Further, sizing treatments for the application of sizing agents such as rosin, starch, wax and the like are also known; see, for example, U.S. Pat. No. 3,993,640 to Pickard et al. which discloses the use of cyclic amides for the treatment of cellulosic materials; US 2003/0127210 to Pelletier et al. which teaches the use of water dispersible polyesters; US 2004/0221976 to Williams et al. which teaches the use of hydrophobic polymers; and EP 0 277 633 to Ikeda et al. which teaches the use of starch ether. Other treatments are also known and used.
Additives have also been suggested for improving printability. For example, U.S. Pat. No. 5,849,447 to Matsuda et al. teaches a non-coated paper for ink-jet or electrophotographic printing which contains a mixture of hydrophilic and hydrophobic fibres; and US 2004/0226675 to Malmstrom et al. teaches the addition of polysaccharide with a polymer dispersion for this purpose.
The present inventors have now discovered that it is possible to provide at least one of hydrophobic and oleophobic properties to a paper sheet by adding a water-based sol-gel dispersion containing up to approximately 30% by weight solids, the dispersion being added at any of several points in the papermaking process, up to a location at which curing by heat or other appropriate means can be provided. Thus, the dispersion can be added directly to the stock slurry from which the paper product is made, or it can be applied to the incipient sheet either as a mist, or by other known coating means following formation. Following addition of the water based sol-gel dispersion to the stock slurry, or application of the dispersion to the sheet at a subsequent stage, and subsequently curing the coating on or within the paper product thus formed, penetration of ink into the treated paper sheet is reduced, thus providing for sharper images, reduced or eliminated bleed through to the back side surface of the sheet and potentially a reduction of ink consumed.
Preferably, the water-based sol-gel dispersion is a three-component system consisting of:                1. an adhesion promoter,        2. nanoparticulate material comprised of an organic prepolymer, and        3. a fluorocarbon polymer.
More preferably, the adhesion promoter is an organofunctional adhesion promoter having a functional group which is one of a vinyl-, methacrylate-, epoxy-, amino-, or mercapto-group.
Preferably, the nanoparticulate material is comprised of organic nanoparticles such as nanowaxes including polyethylene or polypropylene, or prepolymers of condensated silanes such as methyltriethoxysilane, propyltriethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, or phenyltrimethoxysilane and the like. An advantage provided by the use of the silane prepolymers is the possibility to react with the adhesion promoter to build a network of organic prepolymer.
Preferably, the fluorocarbon polymer is a fluoroacrylate or fluoralkyl-polyurethane copolymer. Other similar fluorocarbon polymers may be suitable.
These materials are combined in a ratio of from about 10-25% by weight adhesion promoter, 10-25% by weight nanoparticulate material, and from about 30-70% by weight fluorocarbon polymer.
A sol-gel coating material suitable for use in the manufacture of cellulose based sheet-type products such as paper and the like in accordance with the teachings of the present invention is commercially available, as a dilution of 30% by weight of solids in water, under the designation "Sogetec" from Comp-Tex GmbH, Zur Lohe 48, D-52353 Düren, Germany. This product is marketed as a water-based textile impregnation treatment which can impart a permanent hydrophobic and oleophobic character to a treated substrate. We have found that an effective rate of application of the Sogetec and like materials is about 1-10% by weight solids per liter of water.
A designation of "Sogetec" which has been found to be particularly suitable for this process has been found to be Sogetec 041/30. Other similar treatments containing a three-component water-based sol-gel dispersion system, as discussed above, may be suitable to impart these hydrophobic and/or oleophobic properties to sheet type cellulosic based products such as paper, board and the like, and may include X-Clean® Textile Protect VP-V1/1/KNK-10 which is available from Nano-X GmbH of Theodore Heuss Strasse 11a, Saarbruecken, Germany.
The treated material is then cured at a temperature of from about 60° C. to about 210° C. so as to render the nanoparticle treatment effective. An increased durability of the treatment has been found where the curing temperatures are in the range of from about 100° C. to 200° C.
The additive dispersions of the invention differ from the prior art additives in several respects. Firstly, the dispersions contain two separate systems which do not react with each other, i.e. they neither build up covalent bonds nor do they combine in the form of an alloy. The thin film of fluorocarbon resin especially selected for the purpose, preferably fluoroacrylate precipitated on same is considerably thinner than in the case of a coating consisting exclusively of a fluorocarbon resin. Further, the hydrophobic component in the additive dispersions of the invention bears no relation to any component of the ormocers of the prior art, and comprises no inorganic (i.e. ceramic) microparticles.
Further, the fluorocarbon resins of the additive dispersions of the invention are specifically designed for use together with organosilicon products, and are entirely distinguishable from the perfluorinated side chains of the fluorosilane taught by U.S. Pat. No. 5,932,291.
Experimental Work
The sheet forming process was replicated in the laboratory using a gravity sheet former. In this apparatus, a stock solution is passed under gravity through a known forming fabric and a paper web is thus formed on the fabric surface. The sheet so formed is then dried, removed from the forming fabric, and examined. In the experimental work conducted to determine the effects of the nanoparticle material on the papermaking process, repulped computer paper was used as a fiber source to form a handsheet having a basis weight of from about 20 to 25 gsm (grams per square meter).
In the experiment, 0.1% by weight of solids of the Sogetec 041/30 material (i.e. 0.3% of the liquid) was added to the pulp slurry which contained the repulped papermaking fibers and water in appropriate amounts. Stock which did not contain any of the Sogetec 041/30 material was used as a control. Handsheets (i.e. small paper sheets formed on the fabric) were formed from this dilution using the gravity sheet former as described above. Both the experimental and control handsheets were then dried under identical conditions at temperatures of about 105° C. This drying at elevated temperature also served to cure the Sogetec 041/30 material in the experimental handsheet. Droplets of oil and, separately, water were then applied to the surface of each of the experimental and control handsheets.
It was found that handsheets made from pulp stock containing about 0.1% by weight of the solids of the Sogetec 041/30 material resisted the application of oil and water as compared to the control sheets which did not resist and absorbed each of those liquids immediately. Examination of the experimental and control handsheets showed that droplets of oil and water which were applied to the surfaces of the experimental handsheets containing 0.1% by weight of the solids of the Sogetec 041/30 material remained beaded on the surface of the sheet for several hours and did not penetrate beneath the surface of the sheet. Such effects were observed in concentrations of the particulate material as low as 1.0 ppm (parts per million). By comparison, handsheets which did not contain any of the Sogetec 041/30 material absorbed each liquid immediately.
The Sogetec 041/30 sol-gel material was also applied in an experimental process by first drying the paper sheet, then dip-coating the sheet in about a 0.1% by weight of solids concentration of the Sogetec 041/30, followed by re-drying the sheet; it was found that this method of application produced substantially the same results as described above. Another method of application that was used in experimental testing was to mist the handsheet with an aerosol liquid containing about 0.1% by weight of the solids of the Sogetec 041/30 in water, the misting being by means of a spray applicator onto the non-fabric-contacting side of the wet sheet. The sheet was then dried and cured. In a second instance of the same experiment, the 0.1% by weight of the solids of the Sogetec 041/30 in water was misted onto a dry sheet which was subsequently redried. This second misting method, i.e. misting onto a dried sheet and then redrying and curing it, appears to produce a "one sidedness" to the barrier properties (in other words, only one side of the sheet seems to inherit the barrier properties).
After preparation and initial testing of the cured treated sheets, further testing was performed by applying drops of oil and water on the sheets over a period of several weeks. In each case, the barrier effect persisted. When printing ink was applied to the cured treated sheets in the usual manner, the sheets exhibited no bleed-through and the written image was sharper than on the untreated control sheets.
Thus, nonwoven sheet type products, in particular paper and similar cellulose based products, are rendered both hydrophobic and oleophobic by the incorporation of a nanoparticle material that is formed by a sol-gel type process and is composed of nanowax or condensated silane prepolymer reacted during a curing process with a fluoroamine. This material can be incorporated in small amounts into the stock from which these cellulosic sheet products are formed, or the cellulosic sheet can be treated, prior to a drying stage, by a conventional mist application of a water-based solution containing the nanoparticle material, or by dip coating the sheet in such water based solution containing the nanoparticle material. Regardless of the method by which the nanoparticle material is incorporated into or applied onto the product, it is necessary to expose the sheet-type product to heat so as to cure the nanoparticle material and thus provide the resultant enhancement in barrier properties. After curing, the nanoparticle material imparts a hydrophobic and oleophobic character to the sheet, which assists in resisting penetration by both water and oils.

Sheet-like products exhibiting oleophobic and hydrophobic properties


A refrigeration expansion valve meters the flow of refrigerant therethrough through a flexible orifice that varies in cross sectional area as a function of the pressure differential across the valve. The flexible orifice is provided in a tubular elastomeric element that is supported at opposite ends by rigid support means. A rigid spacer means is provided for engaging the support means to prevent the pressure differential of the refrigeration system from exerting an axial force on the flexible flow metering element.

1. Field of the Invention
This invention relates in general to refrigerant expansion devices. More specifically, it relates to expansion devices that have a variable expansion area that is operated by the pressure differential existing between the high pressure and the low pressure side of a refrigeration system.
2. Description of the Prior Art
A compression refrigeration system comprises: a compressor, a condenser, an expansion device and an evaporator connected in a closed circuit to provide refrigeration. Hot compressed refrigerant vapor from the compressor enters the condenser, where it transfers heat to an external heat exchange medium and condenses. Liquid refrigerant, at a high pressure flows from the condenser to the expansion device, where the refrigerant under goes a pressure drop and at least partially flashes to a vapor. The liquid vapor mixture then flows through the evaporator where it evaporates and absorbs heat from the external surroundings. The low pressure refrigerant vapor then returns to the compressor to complete the circuit.
Although the expansion device is often a simple construction, its role in the refrigeration system is crucial. Ideally, the expansion device should meter refrigerant in a manner such that refrigerant leaving the evaporator is super-heated by a controlled, relatively small amount. The foregoing is desired to prevent any damaging liquid or refrigerant from entering the compressor and to avoid subjecting the compressor to excessive temperature s from highly supper-heated vapor. The performance of the expansion device plays an important role not only in protecting the compressor, but also in determining the cooling capacity of the refrigeration system. Since the system is a closed circuit, any effect the device has on the low or evaporator side is intimately tied in with the performance of the high or condenser side. Most conventional air conditioning systems incorporating compression refrigeration units of the kind described are designed to have a predetermined cooling capacity at a given ambient temperature. The capacity of the system usually decreases at ambient temperatures above the design point. The decrease in capacity of the system at temperatures above the design point is directly related to the type and design of the expansion device.
Among the most commonly used expansion devices are thermostatic expansion valves, capillary tubes and other fixed orifice devices. Thermostatic expansion valves control the flow rate of liquid refrigerant entering the evaporator as a function of the temperature and pressure of the refrigerant gas leaving the evaporator. This control is achieved by varying the cross-sectional area through a needle type valve contained within the valve body. The needle is typically joined to a flexible metal bellows or diaphragm which is, in turn, actuated by a non-heat conducting rod connected at its other end to a sealed bellows. The sealed bellows, in turn, is joined to a thermostatic sensing bulb by means of a capillary tube. This bulb provides feedback to the valve relating to the temperature of the refrigerant leaving the evaporator and the valve responds by increasing or decreasing the flow of refrigerant through the needle valve according to this feedback. While being highly efficient in their operation and readily responsive to changes in load upon system to vary the flow of refrigerant to the evaporator, thermostatic expansion valves are also complicated and relatively expensive. Further, in split system type air conditioning systems, wherein the compressor and condenser are located outside at a remote location from the evaporator, the distance of the sensing bulb from the compressor results in less than optimum conditions in such systems.
Capillary tubes are quite often used in place of thermostatic expansion valves, particularly in smaller applications, wherein ambient air is almost universally utilized as the condensing medium. Although capillary tubes are relatively inexpensive to manufacture and are simple to install, they have some serious operating limitations, particularly when they are operating at conditions above or below the design point of the system.
As an example, as the outdoor ambient temperature increases there is an increase in the pressure differential across the expansion device and the compressor. At higher pressure ratios the compressor pump a lower flow rate, however, a capillary type expansion device at such higher pressure ratio passes a higher flow rate. This flow imbalance results in the loss of stored sub-cooled liquid refrigerant from the high side and loss of superheat and flooding of the low side. These phenomenon greatly reduce system efficiency and performance.
An additional problem is found at relatively low ambient temperatures, wherein the pressure differential across the expansion device is of a relatively small magnitude. Under these conditions the subcooling of the refrigerant entering the expansion device increases as the outdoor ambient temperature falls, leading to more refrigerant being stored in the condenser, which starves the evaporator. As a result, more of the evaporator becomes filled with superheated vapor and the superheat leaving the evaporator increases. Using increased evaporator surface to superheat refrigerant is not putting the surface to its most effective use.
Another known fixed orifice expansion device is the orifice plate. Very simply, an orifice plate comprises a thin plate having an expansion orifice extending therethrough. Orifice plates are small and inexpensive, but they are erratic in performance. Hence, such plates are not in wide use.
In an attempt to provide an alternate expansion device, having the economical advantages of the capillary tube, while being smaller and more efficient in operation, the expansion device described in commonly assigned U.S. Pat. No. 3,642,030 entitled "Refrigerant Throttling Device" and issued on Feb. 15, 1972 in the name of Larry D. Amick was developed. That device comprises a body member having a tubular insert having prescribed length-to-bore diameter ratios, a conical inlet, and a conical exit.
Continuing efforts to develop an economical, efficient and effective fixed orifice expansion device resulted in the development of the expansion device described in commonly assigned U.S. Pat. No. 3,877,248 entitled "Refrigerant Expansion Device" which issued Mar. 1, 1974 in the name of Fred V. Honnold, Jr. That device comprises a body having an expansion conduit extending therethrough with a flat entrance presenting a sharp edge orifice to incoming refrigerant. The sharp edge entrance orifice effects a major portion of the refrigerant pressure drop at the entrance, so that only a short conduit length is necessary to effect the balance of the pressure drop demanded of the device. The body member is incorporated in a unitary coupling member configured to join refrigerant lines from the condenser to the evaporator.
Commonly assigned U.S. Pat. No. 3,992,898 entitled "Moveable Expansion Valve" which issued Nov. 23, 1976, in the name of Richard J. Duell and John A. Ferrel represents a further refinement of a fixed orifice expansion device. In the device of this patent, the refrigerant metering port is formed in a free floating piston which is mounted within a chamber. When refrigerant flows through this device in once direction, the free floating piston moves to one position wherein the refrigerant flow is through the metering port thereby serving as an expansion device. When refrigerant flows through this device in the opposite direction, the free floating piston moves to a second position, wherein refrigerant is allowed to flow through a number of flow channels formed in the outer peripheral surface of the piston to thereby allow substantially unrestricted flow through the device. This arrangement allows such a device to be used, in combination with a second expansion device of the same design in a heat pump system to allow the desired expansion of the refrigerant through the system flowing in both the cooling and heating directions.
In a cooling only system the expansion device of the U.S. Pat. No. 3,992,898 allows a system to be adjusted as to the amount of refrigerant superheat and other expansion parameters by changing the piston contained within the valve body in the field. The piston usually is changed to match the diameter of the metering port, running the length of the piston, with the requirements of a particular system to optimize performance.
U.S. Pat. No. 4,263,787, issued to the assignee hereof, entitled "Expansion Device with Adjustable Refrigerant Throttling" which issued Apr. 28, 1981 to Albert A. Domingorena relates to an improvement of the device of the U.S. Pat. No. 3,992,898 which allows adjusting the diameter of the metering port without having to break into the refrigeration circuit of the system to change the piston.
Summing up the state of the prior art, thermostatic expansion valves, while being highly efficient in their operation and readily responsive to changes in load upon the system to vary the flow of refrigerant to the evaporator, are complicated, expensive, and have drawbacks in certain applications. For this reason they are generally not employed in small applications. As a result, capillary tubes or other fixed orifice expansion devices are generally used in small applications. Such devices are relatively inexpensive, however, as discussed above, they have operating limitations at both high and low ambient temperatures.
From the foregoing, it is evident that the need exists for a refrigerant expansion device which is inexpensive to manufacture and which is effective in performance over a wide range of operating conditions.
Commonly assigned U.S. Pat. No. 5,031,416 entitled "Variable Area Refrigerant Expansion Device Having a Flexible Orifice" which issued Jul. 16, 1991 in the name of Alan S. Drucker and Peter L. Cann discloses such a device. In the '416 patent a refrigerant expansion device is provided wherein the flow metering port is formed an elastomeric element and the elastomeric element deforms in response to an increased pressure differential across the device to decrease the size of the flow metering port. It has been found that in operation, at high pressure differentials, the size of the refrigerant expansion orifice according to the '416 design will change in size as a result of a net axial force on the expansion element which is proportional to the difference between the high pressure and the low pressure side of the refrigeration system.

Variable area refrigerant expansion device having a flexible orifice