JP5698064B2 - Pressure sensor - Google Patents

Description

  The present invention relates to a pressure sensor, and more particularly to a pressure sensor suitable for measuring a pressure close to a vacuum.

  2. Description of the Related Art Conventionally, pressure sensors having a diaphragm structure that detects a change in pressure to be measured as a change in capacitance have been widely known. For example, at present, a pressure sensor including a sensor chip having a sensor diaphragm that isolates a reference vacuum chamber and a pressure introducing portion, and a package including a housing and a cover for housing the sensor chip has been proposed ( For example, see Patent Document 1). In such a pressure sensor, the center portion of the sensor diaphragm is bent toward the reference vacuum chamber due to the difference between the pressure in the reference vacuum chamber and the pressure of the measurement target gas applied via the pressure introducing portion, and the sensor chip The interval between the fixed electrode and the movable electrode changes. As a result, the capacitance between the fixed electrode and the movable electrode changes, and the change in the capacitance is taken out through the cover of the pressure sensor by the electrode lead portion, thereby reducing the pressure of the gas to be measured. It comes to measure.

  Here, the configuration in the vicinity of the electrode lead portion of the above-described conventional pressure sensor will be described with reference to FIG. Each lead pin 210 of the plurality of electrode lead portions 200 of the conventional pressure sensor 100 penetrates the cover 120 constituting the package 110 and protrudes to the outside of the package 110 and is connected to the core wire 310 of the shield cable 300 introduced from the outside. The At this time, the connection portion between each lead pin 210 and the core wire 310 of the shield cable 300 is covered with the electromagnetic shield structure 400 so that noise is not mixed from the outside.

  Conventionally, as shown in FIG. 6, a method of shielding one electrode lead part 200 with one electromagnetic shield structure 400 is employed. Each electromagnetic shield structure 400 employed in this method includes an insulating bush 410 that covers the outer peripheral surface of the electrode lead part 200 protruding from the cover 120, a conductive bush 420 that is placed on the upper surface of the insulating bush 410, The lower shield case 430 is connected to the end portion of the electrode lead part 200, and the upper shield case 440 is combined with the lower shield case 430 to form a shield housing.

JP 2006-3234 A

  However, when the conventional electromagnetic shield structure 400 as described above is employed, if there are n electrode lead portions 200, n component members are required, and the number of necessary component members is proportional to the number of electrode lead portions 200. The score will also increase. For this reason, there existed a problem that productivity fell, in addition to the increase in the manufacturing cost of a sensor. In addition, since one electromagnetic shield structure 400 shields the connecting portion between one shield cable 300 and one lead pin 210, a plurality of electromagnetic shield structures 400 exist. For this reason, if the assembling work of any one of the electromagnetic shield structures 400 fails, noise enters from the outside into the connecting portion, and the structure in which noise easily enters despite the time and labor required for the assembling work. It was.

  The present invention has been made in view of such a situation, and an object of the present invention is to improve productivity by reducing the number of parts of an electromagnetic shield structure in a pressure sensor having a diaphragm structure for detecting a change in pressure to be measured. And

  A pressure sensor according to the present invention includes a cylindrical housing, a conductive package having a plate-like cover joined to an end of the housing, a reference vacuum chamber formed in the package, and a pressure introducing portion. Isolated sensor chip for pressure detection, and a plurality of leads whose one end is electrically connected to the sensor chip and the other end is exposed to the outside of the package through the insertion hole of the cover and connected to the core wire of the shield cable A pressure sensor including a pin and an electromagnetic shield portion that electromagnetically shields a connection portion between the other end of each lead pin and the core of the shield cable, wherein the electromagnetic shield portion includes a plurality of introduction holes for introducing a plurality of lead pins. A conductive plate portion, and a conductive housing portion that is connected to the plate portion and surrounds a connection portion between the other end of each lead pin and the core wire of the shield cable. It is constituted as a single housing having.

  When such a configuration is employed, the connection portion between the other end of each of the plurality of lead pins and the core wire of the shield cable can be collectively shielded by the electromagnetic shield portion configured as a single casing. Therefore, regardless of the number of lead pins, it is only necessary to prepare the constituent members of the electromagnetic shield part one by one, so that the number of parts can be reduced and the productivity can be improved.

  In the pressure sensor, a conductive cylindrical shield member that covers the outer periphery of each lead pin, and a hermetic seal portion formed of sealing glass that hermetically seals between the insertion hole and each cylindrical shield member; The conductive bush which covers the outer peripheral surface of the cylindrical shield member exposed between the outer bottom surface of the plate-shaped portion of the electromagnetic shield portion and the surface of the cover can be provided.

  When this configuration is adopted, it is exposed between the outer bottom surface of the plate-shaped part of the electromagnetic shield part and the surface of the cover (between a plurality of introduction holes for introducing lead pins of the electromagnetic shield part and the hermetic seal part of the cover). The outer peripheral surface of the cylindrical shield member can be covered with a conductive bush. Therefore, electromagnetic noise can be prevented from entering from the exposed portion.

  In the pressure sensor, an insulating bush can be inserted between the lower surface of the conductive bush and the surface of the cover.

  When the conductive bush is in contact with the conductive cover and the cylindrical shield member, noise from the outside passes through the cover, the conductive bush, and the cylindrical shield member in sequence, and shields the other end of each lead pin and the shield. There is a risk of mixing in the connection portion with the core wire of the cable, but by inserting an insulating bush between the lower surface of the conductive bush and the surface of the cover, the path through which electromagnetic noise enters can be blocked. .

  In the pressure sensor, an insulating plate can be disposed between the inner bottom surface of the plate-like portion of the electromagnetic shield portion and the connection portion between the other end of each lead pin and the core wire of the shield cable.

  If such a configuration is adopted, an insulating plate is disposed between the inner bottom surface of the plate-like portion of the electromagnetic shield portion and the connection portion between the other end of each lead pin and the core wire of the shield cable, so that the pressure sensor vibrates. Even if the connecting portion between each lead pin and the shield cable moves, the connecting portion can be prevented from coming into contact with the conductive plate-like portion of the electromagnetic shield portion.

  In the pressure sensor, an insulating plate may be disposed between the ceiling surface of the housing portion of the electromagnetic shield portion and the connection portion between the other end of each lead pin and the core wire of the shield cable.

  If such a configuration is adopted, an insulating plate is disposed between the ceiling surface of the housing portion of the electromagnetic shield portion and the connecting portion between the other end of each lead pin and the core wire of the shield cable, so that the pressure sensor vibrates. Even if the connecting portion between each lead pin and the shield cable moves, it is possible to prevent the connecting portion from contacting the conductive housing portion of the electromagnetic shield portion.

  In the pressure sensor, the plate-like portion and the housing portion of the electromagnetic shield portion can be integrally formed of the same conductive material.

  When such a configuration is adopted, it is not necessary to separately prepare the plate-like part and the housing part of the electromagnetic shield part, and therefore the number of parts can be reduced to the maximum.

  According to the present invention, in a pressure sensor having a diaphragm structure for detecting a change in pressure to be measured, it is possible to improve productivity by reducing the number of parts of the electromagnetic shield structure.

It is sectional drawing of the pressure sensor which concerns on 1st Embodiment of this invention. It is a disassembled perspective view of the electromagnetic shielding part of the pressure sensor shown in FIG. It is explanatory drawing for demonstrating the assembly process of the electromagnetic shielding part of the pressure sensor shown in FIG. It is sectional drawing of the pressure sensor which concerns on 2nd Embodiment of this invention. It is sectional drawing of the pressure sensor which concerns on 3rd Embodiment of this invention. It is explanatory drawing for demonstrating the structure of the electromagnetic shielding part of the conventional pressure sensor.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

<First Embodiment>
First, the pressure sensor 1 according to the first embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the pressure sensor 1 according to this embodiment includes a package 10, a pedestal plate 20 accommodated in the package 10, and a sensor chip 30 that is also accommodated in the package 10 and joined to the pedestal plate 20. And a plurality of electrode lead portions 40 that are directly attached to the package 10 and electrically connect the inside and outside of the package 10. Further, the pedestal plate 20 is separated from the inner wall of the package 10 and is supported by the package 10 only through the support diaphragm 50.

  The package 10 includes a lower housing 11, an upper housing 12 and a cover 13. The lower housing 11 and the upper housing 12 are made of Inconel, which is a corrosion-resistant metal, and the cover 13 is made of Kovar having a thermal expansion coefficient close to that of glass, and is joined by welding.

  The lower housing 11 is a member having a shape in which cylindrical bodies having different diameters are connected. The large-diameter portion 11a has a joint portion with the support diaphragm 50, and the small-diameter portion 11b introduces pressure into which the fluid to be measured flows. Part 10A is formed. A baffle 11c is formed at the joint between the large diameter portion 11a and the small diameter portion 11b, and pressure introduction holes 11d are formed around the baffle 11c at predetermined intervals in the circumferential direction. The baffle 11c serves to bypass the measured fluid such as the process gas from the pressure introduction unit 10A without directly reaching the sensor chip 30 described later, and causes the sensor chip 30 to include a component of the process gas and the process gas. Impurities are prevented from being deposited.

  The upper housing 12 is a member having a substantially cylindrical shape, and forms a vacuum reference vacuum chamber 10 </ b> B in the package 10 together with the cover 13, the support diaphragm 50, the base plate 20 and the sensor chip 30. The reference vacuum chamber 10B is separated by a sensor chip 30 from a region (pressure introduction unit 10A) into which process gas is introduced. In the reference vacuum chamber 10B, a gas adsorbing material called a getter (not shown) is provided, and the degree of vacuum is maintained. Further, on the support diaphragm mounting side of the upper housing 12, a stopper 12a is protruded and formed at an appropriate position in the circumferential direction. The stopper 12a plays a role of restricting the pedestal plate 20 from excessively changing due to a rapid increase in pressure of the fluid to be measured.

  The cover 13 is a plate-like member having a predetermined thickness and a circular shape when viewed from above, and a plurality of electrode lead insertion holes 13a are formed at the center thereof. An electrode lead portion 40 is embedded in the electrode lead insertion hole 13a, and the electrode lead portion 40 and the electrode lead insertion hole 13a are hermetically sealed by a hermetic seal portion 60 made of sealing glass. ing.

  The support diaphragm 50 is made of an Inconel thin plate having an outer shape matched to the shape of the package 10, and the peripheral edge is sandwiched between the lower housing 11 and the upper housing 12 and joined by welding or the like. The thickness of the support diaphragm 50 is, for example, several tens of microns in the case of the present embodiment, and is sufficiently thinner than the pedestal plates 21 and 22. Further, a pressure introduction hole 50 a for guiding pressure to the sensor chip 30 is formed in the central portion of the support diaphragm 50. On both surfaces of the support diaphragm 50, a thin ring-shaped lower pedestal plate made of sapphire, which is a single crystal of aluminum oxide, is provided at a certain distance from the joint between the support diaphragm 50 and the package 10 over the entire circumferential direction (first A base plate 21 and an upper base plate (second base plate) 22 are joined together.

  Each of the pedestal plates 21 and 22 is sufficiently thick as described above with respect to the thickness of the support diaphragm 50, and has a structure in which the support diaphragm 50 is sandwiched between the pedestal plates 21 and 22 in a so-called sandwich shape. . This prevents this portion from warping due to thermal stress generated by the difference in thermal expansion coefficient between the support diaphragm 50 and the base plate 20. Further, a sensor chip 30 having a rectangular shape in a top view made of sapphire, which is a single crystal of aluminum oxide, is bonded to the upper pedestal plate 22 via an aluminum oxide-based bonding material.

  The sensor chip 30 includes a spacer 31 made of a rectangular thin plate having a size of 1 cm square or less when viewed from above, a sensor diaphragm 32 bonded to the spacer 31 and causing distortion in response to application of pressure, and a sensor diaphragm. And a sensor base 33 that forms a vacuum capacity chamber (reference chamber) 30A. Further, the vacuum capacity chamber 30A and the reference vacuum chamber 10B maintain substantially the same degree of vacuum through communication holes (not shown) drilled at appropriate positions of the sensor base 33. The spacer 31, the sensor diaphragm 32, and the sensor base 33 are joined to each other by so-called direct joining to constitute an integrated sensor chip 30.

  Further, in the capacity chamber 30A of the sensor chip 30, fixed electrodes 33b and 33c made of a conductor such as gold or platinum are formed in the recess 33a of the sensor pedestal 33, and the surface of the sensor diaphragm 32 facing this is formed. The movable electrodes 32b and 32c made of a conductor such as gold or platinum are formed thereon. Further, contact pads 35 and 36 made of gold or platinum are formed on the upper surface of the sensor chip 30, and the fixed electrodes 33b and 33c and the movable electrodes 32b and 32c are connected to the contact pads 35 and 36 by wiring (not shown). ing.

  The electrode lead portion 40 includes an electrode lead pin 41 and a metallic cylindrical shield member 42. The center portion of the electrode lead pin 41 is embedded in a metal shield 42 by a hermetic seal portion 43 made of an insulating material such as glass, and an airtight state is maintained between both end portions of the electrode lead pin 41. One end of the electrode lead pin 41 is electrically connected to the sensor chip 30. The other end of the electrode lead pin 41 is exposed to the outside of the package 10 through the insertion hole 13a of the cover 13 and is connected to the core 91 of the shield cable 90 to transmit the output of the pressure sensor 1 to an external signal processing unit. It is supposed to be. A hermetic seal portion 60 is also interposed between the cylindrical shield member 42 and the cover 13. In addition, conductive contact springs 45 and 46 are connected to one end of the electrode lead pin 41. The contact springs 45 and 46 are biased by the contact springs 45 and 46 even if the support diaphragm 50 slightly changes due to a sudden increase in pressure caused by a sudden flow of measured fluid such as process gas from the pressure introduction part 10A. However, it has sufficient softness not to affect the measurement accuracy of the sensor chip 30.

  The connection part between the other end of the electrode lead pin 41 and the shield cable 90 is electromagnetically shielded by the electromagnetic shield part 70. As shown in FIGS. 1 and 2, the electromagnetic shield part 70 is connected to the first shield member 71 having the plate-like part 71 a and the core 91 of the shield cable 90 and coupled to the first shield member 71. It is configured as a single housing having a second shield member 72 that serves as a housing portion surrounding the connecting portion between the other end of the electrode lead pin 41 and the core 91 of the shield cable 90. The first and second shield members 71 and 72 in the present embodiment are made of a conductive metal material such as SUS or Kovar.

  The plate-like portion 71 a of the first shield member 71 is provided with a plurality (four) of introduction holes 71 b for introducing a plurality (four in the present embodiment) of electrode lead portions 40. As shown in FIGS. 1 and 2, the inner bottom surface of the plate-like portion 71 a of the first shield member 71 (the inner surface of the electromagnetic shield portion 70), and the connection portion between each electrode lead pin 41 and the shield cable 90. Between the two, an insulator (insulating plate) 73 having a rectangular shape in plan view is disposed. Also, an insulator (insulating plate) 74 having a rectangular shape in plan view is disposed between the ceiling surface 72a of the second shield member 72 serving as the housing portion and the connection portion between each electrode lead pin 41 and the shield cable 90. Has been.

  Further, a gap is formed between the outer bottom surface of the plate-like portion 71a of the first shield member 71 constituting the electromagnetic shield portion 70 (the outer surface of the electromagnetic shield portion 70) and the surface of the cover 13. In this gap, the cylindrical shield member 42 is exposed to the outside of the package 10. As shown in FIGS. 1 and 2, the exposed outer surface of the cylindrical shield member 42 is made of a Teflon (registered trademark) bush 81, which is an annular member for insulation, and an annular member having conductivity. And a certain SUS bush 82. The Teflon (registered trademark) bush 81 is interposed between the lower surface of the SUS bush 82 and the surface of the cover 13.

  Next, the assembly process of the electromagnetic shield part 70 of the pressure sensor 1 according to the present embodiment will be described with reference to FIG.

  First, as shown in FIG. 3A, the pressure sensor 1 is prepared in advance in a state where each electrode lead portion 40 is inserted into the insertion hole 13 a of the cover 13 and exposed to the outside of the package 10. Next, as shown in FIG. 3B, an annular Teflon (registered trademark) bush 81 is attached to the cylindrical shield member 42 of each electrode lead portion 40 exposed to the outside of the package 10 to form a cylindrical shape. The outer peripheral surface of the shield member 42 is covered. At this time, the Teflon (registered trademark) bush 81 is placed on the surface of the cover 13, and the lower surface of the Teflon (registered trademark) bush 81 is brought into contact with the surface of the cover 13. Subsequently, as shown in FIG. 3C, the SUS bush 82 is placed on the upper surface of the Teflon (registered trademark) bush 81, and the exposed outer peripheral surface of the cylindrical shield member 42 of each electrode lead portion 40 is SUS. Cover with bushing 82. At this time, the lower surface of the SUS bush 82 is brought into contact with the upper surface of the Teflon (registered trademark) bush 81.

  Next, as shown in FIG. 3D, the exposed electrode lead portions 40 are introduced into the respective introduction holes 71b provided in the plate-like portion 71a of the first shield member 71 constituting the electromagnetic shield portion 70. Then, the end portions of the electrode lead portions 40 are attached to the first shield member 71. Subsequently, as illustrated in FIG. 3E, the insulator 73 is placed on the plate-like portion 71 a of the first shield member 71. The insulator 73 is provided with a plurality of introduction holes 73a for introducing the electrode lead pins 41 of the plurality of electrode lead portions 40, and the electrode lead pins 41 are inserted into the introduction holes 73a. Then, as shown in FIG. 3E, the end portion (the other end) of each electrode lead pin 41 exposed from the insulator 73 and the core wire 91 of each shield cable 90 are connected.

  Next, as shown in FIG. 3F, the insulator 74 is placed on the connection portion between each electrode lead pin 41 and each shield cable 90. Subsequently, as shown in FIG. 3G, a second shield member 72 serving as a housing portion is placed on the insulator 74, and the connection portion between each electrode lead pin 41 and each shield cable 90 is connected to the second shield. The electromagnetic shield part 70 which becomes a single housing | casing is comprised by enclosing with the member 72 and couple | bonding the 1st shield member 71 and the 2nd shield member 72. FIG.

  In the pressure sensor 1 according to the embodiment described above, the connection portion between the other end of each of the plurality of electrode lead pins 41 and the core wire 91 of the shield cable 90 is collectively formed by the electromagnetic shield portion 70 configured as a single casing. And can be electromagnetically shielded. Therefore, regardless of the number of electrode lead pins 41, the constituent members (the first shield member 71 and the second shield member 72) of the electromagnetic shield part 70 need only be prepared one by one, so that the number of parts can be reduced. And productivity can be improved.

  Further, in the pressure sensor 1 according to the embodiment described above, between the outer bottom surface of the plate-like portion 71a of the electromagnetic shield part 70 and the surface of the cover 13 (a plurality of introduction holes 71b for introducing lead pins of the electromagnetic shield part 70). The outer peripheral surface of the cylindrical shield member 42 of the electrode lead portion 40 exposed between the cover 13 and the hermetic seal portion 60 of the cover 13 can be covered with a conductive SUS bush 82. Therefore, electromagnetic noise can be prevented from entering from the exposed portion.

  In the pressure sensor 1 according to the embodiment described above, an insulating Teflon (registered trademark) bush 81 is interposed between the lower surface of the SUS bush 82 and the surface of the cover 13. For this reason, electromagnetic noise can be prevented from entering the connecting portion between each electrode lead pin 41 and the shield cable 90 from the outside through the cover 13, the SUS bush 82, and the cylindrical shield member 42 in order.

  In the pressure sensor 1 according to the embodiment described above, the insulator 73 is disposed between the inner bottom surface of the plate-like portion 71 a of the electromagnetic shield portion 70 and the connection portion between each electrode lead pin 41 and the shield cable 90. doing. For this reason, even if the pressure sensor 1 vibrates and the connection portion between each electrode lead pin 41 and the shield cable 90 moves, the connection portion is prevented from contacting the conductive plate portion 71a of the electromagnetic shield portion 70. can do.

  Further, in the pressure sensor 1 according to the embodiment described above, the ceiling surface 72a of the second shield member 72 serving as the housing portion of the electromagnetic shield portion 70, the connection portion between each electrode lead pin 41 and the shield cable 90, An insulator 74 is disposed between them. For this reason, even if the pressure sensor 1 vibrates and the connection portion between each electrode lead pin 41 and the shield cable 90 moves, the connection portion contacts the conductive second shield member 72 of the electromagnetic shield portion 70. Can be prevented.

Second Embodiment
Subsequently, a pressure sensor 1A according to a second embodiment of the present invention will be described with reference to FIG. The pressure sensor 1A according to the present embodiment increases the size (opening area) of the insertion hole 13a formed in the cover 13 of the pressure sensor 1 according to the first embodiment to expand the area of the hermetic seal portion 60, and The Teflon (registered trademark) bush 81 is omitted, and other configurations are substantially the same as those in the first embodiment. For this reason, different configurations will be mainly described, and common configurations will be denoted by the same reference numerals as those in the first embodiment, and detailed description thereof will be omitted.

  As shown in FIG. 4, the diameter of the insertion hole 13 </ b> Aa formed in the cover 13 of the pressure sensor 1 </ b> A according to the present embodiment is formed to be slightly larger than the diameter of the lower surface of the SUS bush 82. As a result, the area of the cross section of the hermetic seal portion 60A formed between the cylindrical shield member 42 of the electrode lead portion 40 inserted into the insertion hole 13Aa of the cover 13 and the inner wall of the insertion hole 13Aa is SUS bush. It is slightly larger than the area of the lower surface of 82. Thus, since the area of the hermetic seal portion 60A is enlarged, the SUS bush 82 does not directly contact the cover 13 even when the SUS bush 82 is disposed in the vicinity of the cover 13. The hermetic seal portion 60A made of an insulating material comes into contact. Therefore, it is possible to insulate between the cover 13 and the SUS bush 82 without providing a Teflon (registered trademark) bush.

  Also in the pressure sensor 1A according to the embodiment described above, the same operational effects as those of the first embodiment can be obtained. Further, since it is not necessary to prepare a Teflon (registered trademark) bush, the number of parts and the number of assembly steps can be further reduced.

<Third Embodiment>
Then, the pressure sensor 1B which concerns on 3rd Embodiment of this invention is demonstrated using FIG. The pressure sensor 1B according to the present embodiment is obtained by downsizing the SUS bush 82 of the pressure sensor 1 according to the first embodiment and omitting the Teflon (registered trademark) bush 81. The other configurations are substantially the same. This is common with the first embodiment. For this reason, different configurations will be mainly described, and common configurations will be denoted by the same reference numerals as those in the first embodiment, and detailed description thereof will be omitted.

  The diameter of the lower surface of the SUS bush 82B of the pressure sensor 1B according to the present embodiment is formed between the cylindrical shield member 42 of the electrode lead portion 40 and the inner wall of the insertion hole 13a of the cover 13 as shown in FIG. It is slightly smaller than the area of the cross section of the hermetic seal portion 60. Since the SUS bush 82B is downsized in this way, even if the SUS bush 82B is disposed in the vicinity of the cover 13, the SUS bush 82B does not directly contact the cover 13 and is an insulating material. It will contact the hermetic seal part 60 which consists of. Therefore, it is possible to insulate between the cover 13 and the SUS bush 82B without providing a Teflon (registered trademark) bush.

  Also in the pressure sensor 1B according to the embodiment described above, the same operational effects as those of the first embodiment can be obtained. Further, since it is not necessary to prepare a Teflon (registered trademark) bush, the number of parts and the number of assembly steps can be further reduced.

  In each of the above embodiments, the example in which the electromagnetic shield portion is configured by two members (a first shield member having a plate-like portion and a second shield member serving as a housing portion) has been described. The plate-like part and the housing part of the part can be integrally formed of the same conductive material. In this case, it is not necessary to prepare the plate-like part and the housing part of the electromagnetic shield part separately, so that the number of parts can be reduced to the maximum.

  Further, in each of the above embodiments, the support diaphragm 50 is made of Inconel, but is not necessarily limited thereto, and may be made of a corrosion-resistant metal such as stainless steel or Kovar. The base plate 20 and the sensor chip 30 are made of sapphire, but are not necessarily limited to this material, and may be made of silicon, alumina, silicon carbide, quartz, or the like. Further, the connection part between the contact pads 35 and 36 and the electrode lead part 40 is configured in the form of so-called contact springs 45 and 46, but is not necessarily limited to this as long as it has sufficient flexibility. The form may be as follows. Furthermore, the electrode lead 40 and the contact pads 35 and 36 may be connected by a sufficiently soft conductive wire. Needless to say, the shapes of the sensor chip 30, the pedestal plate 20, the electrode lead portion 40, and the package 10 are not limited to the above-described embodiments.

  Moreover, although each above embodiment demonstrated the case where an electrostatic capacitance type sensor chip was used, even if it is a pressure sensor provided with the piezoresistive type sensor chip made from silicon instead of this sensor chip, for example. By having the above-described configuration, it is possible to effectively prevent the generated thermal stress from being transmitted to the hermetic seal portion.

1 · 1A · 1B ... Pressure sensor 10 ... Package 10A ... Pressure introducing portion 10B ... Reference vacuum chamber 11 ... Lower housing 12 ... Upper housing 13 ... Cover 13a, 13Aa ... Insertion hole 30 ... Sensor chip 41 ... Electrode lead pin 42 ... Cylindrical Shield member 60, 60A ... Hermetic seal portion 70 ... Electromagnetic shield portion 71a ... Plate-like portion 71b ... Introduction hole 72 ... Second shield member (housing portion)
72a ... ceiling surface 73 ... insulator (insulating plate)
74. Insulator (insulating plate)
81 ... Teflon (registered trademark) bush (insulating bush)
82 / 82B ... SUS bush (conductive bush)
90 ... Shielded cable

Claims (5)

A sensor for pressure detection that isolates a conductive housing having a cylindrical housing and a plate-like cover joined to an end of the housing, and a reference vacuum chamber formed in the package from a pressure introducing portion A plurality of lead pins, one end of which is electrically connected to the sensor chip and the other end of which is exposed to the outside of the package through the insertion hole of the cover and connected to a core wire of a shield cable; the connection portion between the other end the core wire of the shield cable lead pins and a electromagnetic shield electromagnetically shielding, before Symbol electromagnetic shielding portion, the conductive plurality of introduction holes for introducing a plurality of lead pins are provided And a conductive housing that is connected to the plate-like portion and surrounds the connecting portion between the other end of each lead pin and the core wire of the shielded cable. And parts, a pressure sensor that will be configured as a single housing with a,
A conductive cylindrical shield member covering the outer periphery of each lead pin;
A hermetic seal portion made of sealing glass that hermetically seals between the insertion hole and each cylindrical shield member;
A conductive bush covering the outer peripheral surface of the cylindrical shield member exposed between the outer bottom surface of the plate-like portion of the electromagnetic shield portion and the surface of the cover;
A pressure sensor . Further comprising an insulating bushing which is interposed between the lower surface and the cover surface of the conductive bushing, the pressure sensor according to claim 1. Wherein the inner bottom surface of the plate-like portion of the electromagnetic shielding portion, the comprises a connecting portion between the other end the core wire of the shield cable lead pins, an insulating plate disposed between, to claim 1 or 2 The described pressure sensor. Wherein comprises a ceiling surface of the housing portion of the electromagnetic shielding portion, the connection portion between the core wire of the shielded cable and the other end of each lead pin, the insulating plate disposed between any of claims 1 to 3 The pressure sensor according to claim 1. The pressure sensor according to any one of claims 1 to 4 , wherein the plate-like portion and the housing portion of the electromagnetic shield portion are integrally formed of the same conductive material.

Images