Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
  • G01L23/00—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid
  • G01L23/08—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid operated electrically
  • G01L23/18—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid operated electrically by resistance strain gauges
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
  • G01L19/00—Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
  • G01L19/06—Means for preventing overload or deleterious influence of the measured medium on the measuring device or vice versa
  • G01L19/0627—Protection against aggressive medium in general
  • G01L19/0645—Protection against aggressive medium in general using isolation membranes, specially adapted for protection
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
  • G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
  • G01L9/0041—Transmitting or indicating the displacement of flexible diaphragms
  • G01L9/0042—Constructional details associated with semiconductive diaphragm sensors, e.g. etching, or constructional details of non-semiconductive diaphragms
  • G01L9/0044—Constructional details of non-semiconductive diaphragms
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
  • G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
  • G01L9/0041—Transmitting or indicating the displacement of flexible diaphragms
  • G01L9/0051—Transmitting or indicating the displacement of flexible diaphragms using variations in ohmic resistance
  • G01L9/0052—Transmitting or indicating the displacement of flexible diaphragms using variations in ohmic resistance of piezoresistive elements
  • G01L9/0055—Transmitting or indicating the displacement of flexible diaphragms using variations in ohmic resistance of piezoresistive elements bonded on a diaphragm
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T29/00—Metal working
  • Y10T29/49—Method of mechanical manufacture
  • Y10T29/49002—Electrical device making
  • Y10T29/49007—Indicating transducer

Definitions

• the invention relates to a pressure transducer.
• Pressure transducers drastically, some are exposed to very abrupt temperature fluctuations.
• Conventional cleaning methods are used in these industries, where the pressure sensors can be exposed to strong temperature fluctuations.
• cleaning methods are the so-called Cleaning-in-Hace (CIP) or Sterilization-in-Hace (SIP) methods, in which the containers are cleaned or sterilized without first removing measuring devices or measuring sensors.
• CIP Cleaning-in-Hace
• SIP Sterilization-in-Hace
• a spray head is arranged in the container which supplies cleaning chemicals and water or steam and rinses out or boils the container as needed.
• temperatures of eg - 20 ° C up to, for example 200 0 C occur.
• Pressure sensors are usually made up of different components made of different materials, whose differential thermal expansion across the temperature can lead to stresses and strains, and in the worst case even to deformation of the components.
• a plurality of pressure transducers on a pressure transmitter which transmit a pressure acting on a separation membrane to be measured pressure via a pressure-transmitting liquid to a pressure-sensitive measuring element.
• Pressure transmitting fluids have a coefficient of thermal expansion that causes the volume of fluid contained in the pressure transducer to change with temperature. This leads to measurement errors.
• pressure-transmitting fluids are in some applications where high safety and / or hygiene requirements are not or reluctant to use because of the risk that the Fluid may leak if the pressure transducer is damaged. In these applications, so-called 'dry pressure transducers' are preferred, ie. those used without a pressure-transmitting liquid used.
• semiconductor pressure sensors are very popular.
• a particularly preferred example is sapphire carriers with silicon sensors included therein, e.g. Silicon strain resistors or resistance bridge circuits.
• Such sensors are known from the Silicon on Sapphir technology (SOS technology). They offer the advantage that they can be used at very low and even at very high temperatures.
• the silicon sensors are on
• Silicon carrier applied and isolated for example by pn junctions. However, this isolation is effective only at temperatures below about 150 0 C.
• built-up pressure sensors offer the advantage in SOS technology is that sapphire is a dielectric, which ensures good insulation of theRochesiilossenen sensors at temperatures of up to 350 0 C.
• Sapphire is mechanically extremely stable and has a crystal structure that is compatible with that of silicon.
• Sapphire carriers with incorporated therein silicon sensors can be used in a very wide temperature range and also very well tolerated very sudden large temperature fluctuations.
• Sapphire has a thermal expansion coefficient of 8 x 10 6 / K, while stainless steel has a coefficient of 16 x 10 6 / K.
• Titanium has a thermal expansion coefficient equal to that of sapphire. Titanium is a very high quality, but also very expensive material.
• Pressure transducer with a pressure sensor made in SOS technology which allows reliable measurements in a wide temperature range.
• the invention consists in a pressure measuring transducer with a process inlet made of a stainless steel, which serves to fasten the pressure transducer to a measuring location, [0016] a pressure sensor module with [0017] a holder from a stainless steel,
• the metal connection between the support and the process nozzle is a weld.
• the sapphire carrier is applied by brazing to the titanium blank.
• the titanium blank forms the separating membrane and the metallisdie connection between the separating membrane and the holder comprises an annular membrane carrier made of titanium,
• the separating membrane in which the separating membrane is welded flush to the front, and [0035] - which has an annular circumferential recess on its inner side facing the inside of the pressure measuring transducer, [0037] - by which the membrane carrier is able to release stresses, which may be due to the different coefficients of thermal expansion of the separation membrane and the process fluid.
• the separating membrane consists of a stainless steel blank, the metallic connection between the separation membrane and the holder is one
• the titanium blank is on the
• the holder is tubular
• the separation membrane is a stainless steel blank
• the metal is the connection between the holder and the
• the titanium blank is on a second end of the holder
• the invention comprises a fourth variant in which
• the holder is a tubular segment, at the
• Inner wall a radially extending the interior of his paragraph with a paragraph
• the separating membrane is a stainless steel blank
• the titanium disk is arranged, and
• the carrier element is a
• Titanium housing in whose outer wall an annular circumferential recess is provided.
• the invention consists in a method for producing a
• the titanium blank serving as separating membrane by means of a tungsten
• a Rothansdiluss made of stainless steel is used.
• the invention consists in a method for producing a
• the titanium blank by means of brazing, esp.
• [0112] is used in the process connection made of stainless steel.
• the invention further relates to a method for producing a pressure measuring transducer according to the third variant, in which
• a particular advantage is that a pressure sensor module is used, which carries the sapphire support with the silicon sensors introduced therein and the associated titanium blank.
• This module has a stainless steel support, in which the separation membrane is flush-mounted by means of a purely metallic connection, and which is directly flush-welded into process connections made of stainless steel. This makes it possible to calibrate the pressure sensor module in advance and then very flexible to use in conjunction with different process connections.
• Another advantage is that the Druckmes sauf receiver according to the invention with a very small amount of the very expensive material titanium get along. It is always only a single titanium plate needed, and only if this forms the separation membrane is provided an adjoining titanium membrane carrier.
• Fig. 1 shows a section through an inventive
• Fig. 2 shows a section through an inventive
• Fig. 3 shows a section through an inventive
• Fig. 4 shows a section through an inventive
• the titanium blank is part of a carrier element
• Fig. 5 shows a modification of the carrier element of Fig. 4 with a
• annular circumferential recess [0145] annular circumferential recess.
• FIGS 6 to 9 show those shown in Figures 1 to 4
• FIG. 1 shows a section through a first exemplary embodiment of a pressure measuring transducer according to the invention. It comprises a process connection 1, here a flange 1a, made of a stainless steel, which serves to fasten the pressure transducer to a measuring location. Alternatively, of course, other process variants known to those skilled in the art can be used.
• Fig. 6 shows the Druckmes sauf beneficia shown in Fig. 1 in conjunction with a running as a threaded connector Ib process connection 1, which has an external thread 2, which serves to screw the pressure transducer flush with the front into a corresponding threaded hole at the measuring location.
• the pressure sensor module 3 It is a pressure sensor module 3 is provided that front flush by means of a pure metallic compound is used in the Prozeßansdiluss 1.
• the pressure sensor module 3 has an annular holder 5 made of a stainless steel.
• the annular holder 5 is flush-mounted in the Prozeßansdiluss 1 is inserted.
• the annular support 5 has an L-shaped transverse surface and is versdi dressingt with its outer edge to the Prozeßansdiluss 1.
• the pressure sensor module 3 comprises a metallisdie separation membrane 7, which is inserted flush with the front by means of a purely metallic compound in the holder 5.
• a pressure p to be measured acts on an outer side of the separating membrane 7.
• the separation membrane 7 is made of titanium.
• the purely metallic connection between the separation membrane 7 and the holder 5 made of stainless steel comprises an annular membrane support 9 made of titanium.
• the annular membrane support 9 is flush with the holder 5 and the process nozzle 1 from the front and the separation membrane 7 is welded into the membrane support 9 flush with the front.
• the membrane support 9 on its front inner side an annular shoulder surface, on which the separation membrane 7 rests with an outer edge.
• the membrane support 9 is thus zwisdien the separation membrane 7 made of titanium and the annular connected to the Processansdiluss 1 holder 5.
• the membrane support 11 is located in the holder 5 and the outer edge is such versdi dressingt with an inner edge of the holder 5, that both components flush with Drain the process outflow 1.
• the holder 5 and the Processansdiluss 1 are both made of stainless steel.
• the purpose of the membrane support 9 is to absorb stresses which may arise due to the different thermal expansion coefficients of the separating membrane 7 and the holder 5 or of the process nozzle 1.
• the membrane support 9 has an annular circumferential recess 11 on the inside of the pressure measuring transducer facing inside. As a result, the separation membrane 7 is protected against temperature-dependent mechanical stresses that could affect the reproducibility and the accuracy of the measurement results.
• the pressure sensor module 3 comprises a sapphire carrier 13 with therein Ltd.
• the sapphire carrier 13 with the silicon sensors incorporated therein is a sensor chip made in SOS technology.
• the silicon sensors 15 are preferably individual expansion resistors or resistance bridge connections constructed from these.
• Pressure sensors manufactured in SOS technology are well known from the prior art and therefore are not explained here.
• a great advantage of these pressure sensors is that they can be used in a very wide temperature range, for example from -70 0 C to + 200 0 C, and at very sudden temperature fluctuations.
• the sapphire carrier 13 is applied flat on a titanium blank.
• the connection is preferably by brazing.
• other soldering methods e.g. Vacuum brazing, can be used.
• Sapphire and titanium have practically identical coefficients of thermal expansion, so that the two elements are connected to each other almost without tension even with large and / or very rasiien temperature changes.
• the pressure p is transferred areally.
• the titanium blank simultaneously serves as the separating membrane 7.
• the pressure transducer illustrated in FIGS. 1 and 6 is preferably made by initially welding the titanium blank serving as the separating membrane 7 flush with the front side into the annular membrane carrier 9 by means of tungsten inert gas welding. Subsequently, the sapphire carrier 13 is soldered with the silicon sensors 15 introduced therein by brazing on a pointing into the interior of the sensor rear of the titanium blank.
• the membrane carrier 9 is preferably flush-mounted in the annular holder 5 made of stainless steel by means of an electron beam Schung.
• vanadium is preferably used as welding filler.
• the holder 5 is preferably flush-mounted in the process connection 1 made of stainless steel by means of a tungsten inert gas welding.
• FIGS. 2 and 7 show a further exemplary embodiment of a pressure measuring transducer according to the invention.
• the pressure transducer has a process connection 1 made of a stainless steel, which serves to fasten the pressure measuring transducer at a measuring location.
• a flange is shown in the embodiment shown in Fig. 2.
• a threaded connector is shown in Fig. 7 .
• a pressure sensor module 17 which is flush-mounted by means of purely metallized compounds in the process connection 1. It comprises an annular holder 19 made of a stainless steel, which in the process connection 1 is white know.
• the annular holder 19 has a nearly square cross-section, and is inserted into a form-fitting recess, which is flush with the process connection 1 and is flush with the recess.
• the holder 19 is weii with its outer edge with the Prozeßansiiluss 1 versii.
• the separation membrane 23 is not made of titanium, but of a stainless steel, and the purely metallic compound consists in a weld over which the separation membrane 23 is flush mounted directly into the holder 19.
• the holder 19 on its front inner side an annular shoulder surface 25 on which the separation membrane 23 rests with an outer edge.
• the same material is used for the separation membrane 23 as for the holder 19 and the process connection 1.
• This offers the advantage that the process connection 1, support 19 and separation membrane 23 have the same coefficient of thermal expansion, and temperature-dependent voltages or tensions of the separation membrane 23 are largely avoided.
• the pressure sensor module 17 here again comprises the previously described sapphire carrier 13 applied to a titanium disk 27 with the silicon sensors 15 introduced therein. Unlike in the previous exemplary embodiment, however, the titanium disk 27 does not directly form the separating diaphragm but is mechanically connected to the latter Separation membrane 23 connected, that a deflection of the separation membrane 23 causes a corresponding deflection of the titanium blank 27. For this purpose, the titanium blank 27 is applied to the inside of the separating membrane 23. For this purpose, e.g. a brazed or vacuum brazed used.
• this mechanical connection is made via a plurality of brazing connection points distributed over the connection surface.
• These point connections are sufficient to transmit the pressure p acting on the separation membrane 23 in a planar manner.
• they provide sufficient clearance for the thermal expansion of the bonded elements so that, as the temperature changes, only minor shearing forces act on the braze joints and on the titanium blank 27.
• the pressure sensor module 17 is thereby protected from temperature-related stresses or strains.
• the last contact pressure transducer is preferably produced by using the stainless steel blank which serves as separation membrane 23 by means of a tungsten Inert gas welding is welded flush into the annular holder 19 made of stainless steel. Thereafter, the titanium blank 27 is brazed, preferably by means of braze joints, on the inside of the stainless steel blank. As a result, the sapphire carrier 13 with the silicon sensors 15 introduced therein is soldered onto the rear side of the titanium blank 15. This is preferably done by brazing or by vacuum brazing. Absii issued the unit thus formed is flush mounted in the process approach 1 by the holder 19 is flush mounted by means of a tungsten inert gas welding in the process connection 1 made of stainless steel.
• FIGS. 3 and 8 show a further embodiment of a pressure measuring transducer according to the invention.
• the pressure transducer has a process connection 1 made of a stainless steel, which serves to fasten the pressure measuring transducer at a measuring location.
• a Flansdi is shown in the embodiment shown in Fig. 3.
• a threaded connector is shown in Fig. 8.
• a pressure sensor module 29 is also provided here, which has a holder 31 made of a stainless steel, which is flush-mounted in the process connection 1 by means of a purely metallized connection.
• the purely metallic compound is for example a weld.
• the holder 31 is substantially tubular and has a first end 33 which terminates in front flush with the process connection 1. In this first end 33 is flush with the front by means of a purely metallic compound, the metallic separation membrane 35 is inserted.
• the holder 31 has on its end face an annular recess whose depth corresponds to the thickness of the separating membrane 35.
• the separation membrane 35 consists in the embodiments shown in FIGS. 3 and 8 of a stainless steel.
• the same material is used for this purpose, as for the holder 31 and the process connection 1. This offers the advantage that holder 31, process connection 1 and separation membrane 35 have the same thermal expansion coefficient, and the temperature-dependent stresses or strains of Separating membrane 35 are largely avoided.
• the pressure sensor module 29 here again comprises the sapphire carrier 13 already applied to a titanium blank 27 with the silicon sensors 15 introduced therein.
• the titanium blank 27 does not serve directly here as a separating membrane, but is mechanically connected to the separating membrane 35 in this way. that a deflection of the separation membrane 35 causes a corresponding deflection of the titanium blank 27.
• the sapphire carrier 13 with the silicon sensors 15 introduced therein is arranged on an outer side of the titanium blank 27 facing away from the holder 31.
• the separation membrane 35 is connected via a purely mechanical connection, in this case a plunger 39, with the titanium blank 27, which serves to transfer a mechanical deflection of the separation membrane 35 onto the titanium blank 27 and above onto the sensor chip.
• the sapphire support 13 is connected by brazing or by vacuum brazing with the titanium blank 27.
• the last pressure measuring transducer is preferably made by welding the plunger 39 centrally onto the stainless steel blank serving as a separating membrane 35. Subsequently, the separation membrane 35 connected to the plunger 39 is welded by means of a tungsten inert gas welding flush in the first end 33 of the tubular holder 31 made of stainless steel. In parallel, the sapphire support 13 is brazed to the backside of the titanium blank 27 by brazing or vacuum brazing. As a result, the front side of the titanium blank 27 is connected to the plunger 39 and the second end 37 of the holder 31 by brazing or vacuum brazing.
• the pressure sensor module 29 obtained in this way is flush-mounted in the process connection 1 by the first end 33 of the holder 31 gesüs quarantt by means of a tungsten inert gas welding flush with the process flow 1.
• FIGS. 4 and 9 show a further exemplary embodiment of a pressure measuring transducer according to the invention.
• the pressure transducer has a process nozzle 1 made of a stainless steel, which serves to fasten the pressure measuring transducer at a measuring location.
• a flange is shown in the embodiment shown in Fig. 4, a flange is shown in Fig. 9, a threaded connector is shown.
• Pressure sensor module 41 is provided which has a holder 43 made of a stainless steel, the front flush by means of a purely metallic compound in the Process connection 1 is used.
• the purely metallic compound is for example a whitening.
• the holder 43 is a substantially tubular segment, to whose
• Inner wall a radially extending into its interior extending paragraph 45 with a central coaxial with a longitudinal axis L of the holder 43 extending through recess 47 is integrally formed.
• the holder 43 has a first end 49 flush with the front
• the metallic separation membrane 51 is inserted.
• the holder 43 has on the end face an annular recess whose depth corresponds to the thickness of the separating membrane 51.
• the separation membrane 51 consists in the embodiments shown in FIGS. 4 and 9 of a stainless steel.
• the same material is used for this purpose, as for the holder 43 and the process connection 1. This offers the advantage that holder 43, process 1 and separation membrane 51 have the same thermal expansion coefficient, and of the temperature-dependent stresses or strains Separation membrane 51 can be largely avoided.
• the pressure sensor module 41 here again comprises the sapphire carrier 13 already applied to a titanium disk 53 with the silicon sensors 15 introduced therein.
• the titanium disk 53 does not serve directly here as a separating diaphragm, but is mechanically connected to the separating diaphragm 51 in such a way that a deflection the separation membrane 51 causes a corresponding deflection of the titanium blank 53.
• a closed end of the Titanronde 53 support member 55 is provided here, on which the sapphire support 13 is arranged with the introduced silicon sensors 15 on a side facing away from the holder 43 of the titanium disk 53.
• the support member 55 is a preferably one-piece substantially cylindrical housing made of titanium, the bottom of which forms the titanium disk 53.
• a tube segment 57 is integrally formed on its side facing away from the Titanronde 53, that end is inserted by means of a purely metallic compound in the recess 47 of the paragraph 45.
• the recess 47 has at its side facing away from the separation membrane 51 a region with an enlarged inner diameter, in which the pipe segment 57 is inserted such that the inner wall of the pipe segment 57 is flush with the Inner wall of the recess 47 absdi vinegart.
• the purely metallic compound is preferably a welded joint or a braze.
• Plunger 59 is provided, which is connected to the separation membrane 51 and the titanium blank 53.
• the plunger 59 is, for example, welded centrally on the inside of the separation membrane 51 and leads parallel to the longitudinal axis L of the holder 43 through the recess 47 in the shoulder 45 and the tube segment 57 into the housing, where it with the inside of the titanium disk 53, for example by a braze joint is connected.
• the plunger 59 serves to transfer the mechanical deflection of the separation membrane 51 to the titanium blank 53 and above onto the sapphire support 13 with the silicon sensors 15 introduced therein.
• a pressure compensating bore 61 passing through the shoulder 45 is preferably provided.
• An advantage of this embodiment is that the connection between titanium and stainless steel takes place here via the tube segment 57.
• the diameter of the pipe segment 57 is much smaller than that of the titanium disk 53. This requires a smaller contact surface and a higher thermal stability of the construction.
• the connection between titanium and stainless steel is spatially separated from the titanium blank 53. As a result, effects of thermal stresses in the area of the contact surfaces on the titanium blank 53 are significantly reduced.
• FIG. 5 shows an embodiment of such a support member 65.
• the support member 65 is also a titanium housing with a molded thereon a housing neck forming tube segment 57 that is inserted by means of a metal-hen connection in the paragraph 45.
• the interior of the support member 65 is cylindrical.
• the outer wall has a hollow cylindrical region 67, which adjoins the tube segment 57, of lesser wall thickness, in which the annular peripheral recess 63 runs. Through the recess 63 of this housing portion is able to absorb stresses that may be caused by the different thermal expansion coefficients of the pipe segment 57 and the paragraph 45.
• the region 67 is adjoined by a pipe segment 57 facing away from the titanium disk 53 adjacent hollow cylindrical area 69 with greater wall thickness.
• the different wall thicknesses provide additional protection for the Titanronde 53 against tension.
• All known pressure transmitters have the advantage that they are flush-mounted and have a purely metallic absorbency for the process. As a result, they are particularly suitable for applications in which high demands are placed on hygiene. They are very easy to clean, and can not only be used in a wide temperature range due to their design, but also withstand sudden temperature changes, as they may occur, for example, in the aforementioned industrial cleaning and / or sterilization. This is esp. Possible because all compounds Metallisdie compounds and was completely dispensed with pressure-transmitting liquids.
• a further advantage is that the pressure measuring devices according to the invention are of modular construction.
• the pressure sensor modules 3, 17, 29, 41 can thereby be calibrated in advance and subsequently used very flexibly in various types of process dilution.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Analytical Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Combustion & Propulsion (AREA)
• Measuring Fluid Pressure (AREA)

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• 2006
  • 2006-07-26 DE DE102006035230A patent/DE102006035230A1/de not_active Withdrawn
• 2007
  • 2007-06-28 EP EP07786898A patent/EP2057451A1/de not_active Withdrawn
  • 2007-06-28 WO PCT/EP2007/056507 patent/WO2008012162A1/de active Application Filing
  • 2007-06-28 CN CN2007800324028A patent/CN101512314B/zh not_active Expired - Fee Related
  • 2007-06-28 US US12/309,633 patent/US8033179B2/en not_active Expired - Fee Related

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