JP2012063219A - Pressure sensor, and a manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure sensor suppressing degradation of pressure detection accuracy, and a manufacturing method of the same.SOLUTION: The pressure sensor is constituted by combining a first housing and a second housing. The second housing has a cylindrical shape and its hollow part is partitioned by a metal diaphragm. The first housing has a columnar shape and, at the end of the metal diaphragm side, a first groove provided with a sensor element and a second groove provided with an annular seal member are formed. A pressure detection chamber constituted of the first groove and the metal diaphragm is filled with a pressure medium, and the first housing is pressed to the metal diaphragm side by a caulked portion of the second housing. On a portion of the second housing opposing the side face of the first housing, a through-hole is formed to allow a gap between the side face of the first housing and the opposing portion of the second housing to communicate with the outside, and the gap is filled with a resin.

Description

  The present invention relates to a pressure sensor formed by combining a first housing in which a sensor element and a terminal are fixed and a second housing in which a metal diaphragm is fixed, and a method for manufacturing the same.

  Conventionally, for example, as shown in Patent Document 1, a casing formed by integrally assembling a first case having a recessed portion at the tip and a second case having a hollow, a tip of the first case, and a first case A metal diaphragm provided between the second case and a portion facing the tip of the first case, a pressure detection chamber formed between the metal diaphragm and the recess of the first case, and a pressure detection chamber A pressure sensor, a pressure transmission medium filled in the pressure detection chamber, a terminal electrically connected to the sensor element, and a wire electrically connecting the terminal and the sensor element. Sensors have been proposed. In this pressure sensor, the pressure acting on the metal diaphragm is transmitted to the sensor element via the pressure transmission medium. In addition, an annular groove surrounding the above-described recess is formed at the tip of the first case, and the above-described pressure detection chamber is sealed (air-tightly sealed) by an O-ring provided in this groove. Yes.

JP 2010-85307 A

  In order to manufacture the pressure sensor described in Patent Document 1, first, a pressure transmission medium is injected into the recess of the first case with the tip of the first case facing vertically upward. Next, in a state where the recess is filled with the pressure transmission medium, the tip of the first case is inserted into the hollow of the second case, thereby forming a pressure detection chamber and surrounding the pressure detection chamber with an O-ring. . Finally, a part of the second case is caulked to fix the first case and the second case, and the pressure detection chamber is sealed with an O-ring.

  Thus, in order to manufacture the pressure sensor described in Patent Document 1, the first case must be inserted into the second case in a state where the pressure transmission medium is injected. Therefore, when the first case is inserted into the hollow of the second case, it intersects in the vertical direction in order to prevent the pressure transmission medium from spilling due to the contact between the first case and the second case. In the direction, it is desirable to form a gap between the first case and the second case and insert them in a non-contact state. This gap is eliminated to some extent by caulking the second case, but not all.

  The technical feature of Patent Document 1 is that a through hole that communicates the gap and the outside is formed in a portion of the second case facing the first case. When this through hole is not present, the gas in the above-described gap expands due to fluctuations in the external temperature. The pressure due to this expansion is transmitted to the pressure transmission medium via the O-ring, which may reduce the pressure detection accuracy. Furthermore, as a result of the expanded gas flowing into the pressure detection chamber through the O-ring, bubbles are generated in the pressure detection chamber, which may reduce the pressure detection accuracy. On the other hand, when there is a through hole as in the pressure sensor described in Patent Document 1, the pressure of the gas in the gap and the pressure of the gas in the external atmosphere are the same. Transmission of excess pressure to the transmission medium) is suppressed, and generation of bubbles in the pressure detection chamber is suppressed. Thereby, the fall of the pressure detection precision is suppressed.

  Incidentally, as described above, in the pressure sensor disclosed in Patent Document 1, a through hole is formed in the second case. In the case of this configuration, the O-ring is exposed to the external environment through the through hole and the above-described gap, so that the O-ring may be deteriorated. When the O-ring deteriorates, the sealing performance of the pressure detection chamber decreases, and the pressure transmission medium leaks to the outside. As a result, the pressure detection accuracy may decrease.

  In view of the above problems, an object of the present invention is to provide a pressure sensor in which a decrease in pressure detection accuracy is suppressed, and a manufacturing method thereof.

  In order to achieve the above object, the invention according to claim 1 is a pressure sensor comprising a first housing in which a sensor element and a terminal are fixed, and a second housing having a metal diaphragm. The second housing has a cylindrical shape, and the hollow thereof is divided by the metal diaphragm into an accommodation space for accommodating the first housing and an introduction space for introducing the pressure fluid to be detected. The housing has a columnar shape, and a first groove provided with a sensor element and a part of a terminal and a second groove provided with an annular seal member are formed at an end on the metal diaphragm side, The entire circumference of the first groove is surrounded by the second groove, and a pressure detection chamber is constituted by the first groove and the metal diaphragm. The pressure detection chamber acts on the metal diaphragm. The end of the second housing on the housing space side is caulked with respect to the first housing, and the caulked site causes the first fluid to be transmitted to the sensor element. One housing is pressed against the fixed portion of the metal diaphragm in the second housing via a seal member, and is a portion that divides a housing space in the second housing, and that is opposed to a side surface of the first housing. The side surface of the first housing and the opposite part of the second housing, which are formed with at least one through-hole that communicates between the housing space and the outside and are part of the housing space and separated from the pressure detection chamber by the seal member The gap between them is filled with the resin injected through the through hole.

  Thus, according to this invention, the clearance gap between the side surface of a 1st housing and the opposing site | part of a 2nd housing is satisfy | filled with resin. Therefore, since the annular seal member is not exposed to the external environment, the deterioration of the seal member is suppressed, and the leakage of the pressure medium is suppressed. Further, unlike the configuration in which the gap is filled with gas, an increase in the pressure in the pressure detection chamber due to the expansion of the gas due to an increase in the external temperature is suppressed. In other words, as a result of the gas in the expanded gap flowing into the pressure detection chamber via the seal member due to fluctuations in the external temperature, the generation of bubbles in the pressure detection chamber is suppressed. As described above, according to the present invention, in the pressure detection chamber due to the leakage of the pressure medium due to the deterioration of the seal member, the increase in the pressure of the pressure detection chamber due to the gas expansion, and the inflow of the gas into the pressure detection chamber. Generation of bubbles is suppressed, and a decrease in pressure detection accuracy due to these is suppressed.

  In addition, when external temperature rises, resin expand | swells similarly to gas. However, the resin is located between the side surface of the first housing and the facing portion of the second housing, and the seal member that seals the pressure detection chamber is located at the end of the first housing on the metal diaphragm side. Yes. According to this, since the resin and the seal member are not adjacent to each other, even if the resin expands, the pressure due to the expansion is difficult to be applied to the seal member, and therefore, is not easily applied to the pressure detection chamber. Thus, in the present invention, even if the resin expands, the pressure in the pressure detection chamber is unlikely to fluctuate.

  According to a second aspect of the present invention, a plurality of through holes are formed in the second housing, and at least one of the plurality of through holes is a through hole for injecting resin into the gap. A configuration in which at least one other is a through-hole for extracting gas from the gap is suitable. This makes it easier to fill the gap in the gap between the first housing and the second housing as compared to the configuration with one through hole. This is because the above-mentioned gap has a very small volume, so that it is difficult to surround the resin. However, if there are a plurality of through holes, the resin can be injected from the plurality of through holes, and the resin can be easily filled. Because. Further, if at least one through hole among the plurality of through holes is a through hole for injecting resin, and at least the other one through hole is a through hole for removing gas in the gap, Resin is easy to turn and filling becomes easy.

  According to a third aspect of the present invention, it is preferable that the plurality of through holes are formed at equal intervals along the circumferential direction of the central axis of the second housing.

  For example, when the interval between adjacent through holes in the circumferential direction is indefinite, a place with a long adjacent interval is locally generated. In this case, it is difficult for the resin injected from the two through holes located at both ends of the place where the adjacent interval is long to reach the middle of the adjacent interval (the farthest place where the resin injected through the through hole flows). Therefore, it becomes difficult to fill the resin in the gap between the first housing and the second housing located in the middle.

  On the other hand, according to the invention described in claim 3, since the interval between adjacent through holes in the circumferential direction is constant, the distance between the middle of the adjacent interval and the through hole is also constant. . According to this, it is suppressed that it becomes difficult for the resin injected from the through hole to flow in the middle of the adjacent interval, and the resin is filled in the gap between the first housing and the second housing located in the middle. Is suppressed from becoming difficult.

  As described in claim 4, an annular third groove surrounding the central axis of the first housing is formed on the side surface of the first housing, and the third groove and the through hole communicate with each other. Is preferred.

  When there is no third groove, the resin injection pressure is such that the resin is injected into the circumferential direction of the central axis of the first housing and the gap located in the intersecting direction intersecting the circumferential direction. In this case, the injection pressure of the resin becomes strong, and the resin may flow to an unexpected place.

  On the other hand, according to the configuration of the fourth aspect, the resin can be filled in the entire circumference of the side surface of the first housing along the third groove without increasing the injection pressure of the resin. Therefore, the injection pressure of the resin can be set to such an extent that the resin is injected into the gap located in the direction intersecting the annular third groove. Thereby, compared with the structure without the third groove, the injection pressure of the resin is lowered, so that the resin is prevented from flowing to an unexpected place.

  As a specific configuration of the first housing and a specific configuration of caulking, as described in claim 5, the first housing includes a first pillar portion provided in a hollow of the second housing, and a first pillar portion. And a second column portion that is connected to an end portion of the column portion that is away from the metal diaphragm and is exposed from the second housing, and the diameter of the first column portion is longer than the diameter of the second column portion. In addition, it is possible to employ a caulked configuration in which the end portion on the first housing side in the second housing is bent toward the end portion side away from the metal diaphragm in the first column portion.

  Since the operational effect of the invention described in claim 6 is the same as that of the invention described in claim 1, the description thereof is omitted.

  The assembling step includes an inserting step of inserting the first housing into the hollow of the second housing, and a caulking step of caulking an end portion of the second housing on the first housing side after the inserting step. It is preferable to have. Thus, by fixing the first housing and the second housing before injecting the resin, the fixing position of the first housing and the second housing may be shifted due to the injection pressure of the resin, or the pressure medium The occurrence of problems such as leakage is suppressed.

  According to an eighth aspect of the present invention, it is preferable to have a degassing step of removing the gas mixed in the resin by putting the fixed first housing and second housing into the vacuum chamber after the injection step. According to this, as a result of the gas mixed in the resin expanding and contracting, it is possible to suppress an excessive pressure from being applied to the pressure detection chamber.

  Further, unlike the configuration described in claim 7, as described in claim 9, the assembling step may be an insertion step of inserting the first housing into the hollow of the second housing. Then, as described in claim 10, after the injecting step, a caulking step for caulking the end of the second housing on the first housing side is performed, and after the caulking step, the fixed first housing and second housing A degassing step of removing gas mixed in the resin may be carried out by putting in the vacuum chamber.

It is a front view which shows schematic structure of the pressure sensor which concerns on 1st Embodiment. It is sectional drawing which follows the II-II line | wire of FIG. It is a front view for demonstrating a 3rd groove | channel.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a front view illustrating a schematic configuration of the pressure sensor according to the first embodiment. 2 is a cross-sectional view taken along line II-II in FIG. FIG. 3 is a front view for explaining the third groove. Hereinafter, a line passing through the center of the first housing 10 in the direction in which the first housing 10 and the metal diaphragm 60 are arranged is referred to as a center line. In the present embodiment, the center of the second housing 50 is also located on this center line. The center line coincides with the center axis of each of the first housing and the second housing described in the claims.

  As shown in FIGS. 1 and 2, the pressure sensor 100 is configured by assembling a columnar first housing 10 and a cylindrical second housing 50. The sensor element 20 and the terminal 30 are fixed to the first housing 10, and the metal diaphragm 60 and the ring weld 61 are fixed to the second housing 50. The hollow of the second housing 50 is divided by the metal diaphragm 60 into an accommodation space for accommodating the first housing 10 and an introduction space for introducing the pressure fluid to be detected. A part of the second housing 50 is provided in a pipe through which the pressure fluid flows. The pressure fluid flows into the introduction space, and the pressure of the pressure fluid that has flowed in acts on the metal diaphragm 60. Yes.

  The first housing 10 is formed of a resin material such as PPS or PBT, and the first pillar portion 11 and the second pillar portion 12 are integrally connected. The diameter of the 1st pillar part 11 is longer than the diameter of the 2nd pillar part 12, the 1st pillar part 11 is arrange | positioned in the accommodation space of the 2nd housing 50, and the 2nd pillar part 12 is arrange | positioned outside. Has been.

  A first groove 13 for providing a part of the sensor element 20 and the terminal 30 and a second groove 14 for providing an O-ring 62 are provided at the end 11 a on the metal diaphragm 60 side in the first column part 11. And are formed. The second groove 14 has an annular shape, and the first groove 13 is surrounded by the second groove 14. As shown in FIG. 2, the pressure detection chamber 15 is formed by the first groove 13 and the metal diaphragm 60, and the pressure detection chamber 15 is filled with the pressure medium 16. Thereby, the pressure of the pressure fluid that has acted on the metal diaphragm 60 is acted on the sensor element 20 via the pressure medium 16.

  In the present embodiment, a third groove 17 is formed on the side surface 11 b of the first column part 11. As shown in FIG. 3, the third groove 17 has an annular shape surrounding the center line.

  The sensor element 20 includes a semiconductor substrate 21, a gauge resistor (not shown) formed on the thin portion 22 of the semiconductor substrate 21 that is locally thinned, and a pedestal 23. The pedestal 23 is made of glass, and the pedestal 23 and the semiconductor substrate 21 are anodically bonded. The pedestal 23 is fixed to the wall surface of the first groove 13 via an adhesive (not shown). The sensor element 20 functions to convert the pressure applied to the thin portion 22 into an electrical signal.

  The terminal 30 is insert-molded in the first housing 10, a part on one end 30 a side is exposed from the first groove 13, and the other end 30 b is the first pillar in the second pillar part 12. It is exposed from the end part 12a opposite to the connection end with the part 11. A wire 31 is connected to a portion of the terminal 30 provided in the first groove 13, and the terminal 30 and the sensor element 20 are electrically connected via the wire 31. Thereby, the electrical signal of the sensor element 20 is output to the outside via the wire 31 and the terminal 30. In addition, the part exposed from the 1st groove | channel 13 in the terminal 30 is coat | covered with the sealing resin 32, and the other edge part 30b is shown in FIG. 2 at the edge part 12a of the 2nd pillar part 12, as shown in FIG. It is surrounded by the linked enclosure 18. The enclosure 18 and the end 30b constitute a connector.

  The second housing 50 is made of a metal material such as aluminum, and is formed by connecting a first tube portion 51 and a second tube portion 52. The inner diameter of the first cylinder part 51 is longer than the inner diameter of the second cylinder part 52, and the hollows of the first cylinder part 51 and the second cylinder part 52 are separated by the metal diaphragm 60. The hollow of the 1st cylinder part 51 fulfill | performs the function which accommodates the 1st pillar part 11 of the 1st housing 10, and the hollow of the 2nd cylinder part 52 fulfill | performs the function which introduces a pressure fluid.

  As shown in FIG. 2, the inner diameter of the first cylinder portion 51 is constant, and the inner diameter of the second cylinder portion 52 is constant after gradually decreasing as the distance from the metal diaphragm 60 increases. A screw groove 53 for fixing to a screw hole provided in the pipe is formed on the outer wall of the second cylinder portion 52 where the inner diameter is constant. An annular fixing surface 52 a for fixing the metal diaphragm 60 is provided at the connection end of the second cylindrical portion 52 with the first cylindrical portion 51. The fixed surface 52a and the end portion 11a of the first pillar portion 11 are opposed to each other with the metal diaphragm 60 and the ring weld 61 interposed therebetween. In addition, the connection end with the 1st cylinder part 51 in the 2nd cylinder part 52 is equivalent to the fixing | fixed part of the metal diaphragm in a 2nd housing as described in a claim.

  The end portion of the first cylinder portion 51 away from the second cylinder portion 52 is caulked and bent toward the connecting end side of the first column portion 11 with the second column portion 12, and the caulked and bent portion. The first pillar portion 11 (first housing 10) is pressed against the fixed surface 52a side (hereinafter, referred to as a caulking portion 54).

  As shown in FIGS. 1 and 2, a through hole 56 is formed in a portion 55 of the first cylinder portion 51 that faces the side surface 11 b of the first column portion 11. It communicates with a gap (hereinafter simply referred to as a gap) between the side surface 11 b of the column part 11 and the facing part 55. In the present embodiment, two through holes 56 are formed in the facing portion 55, and these two through holes 56 are formed at equal intervals in the circumferential direction of the center line. If another expression is used, the two through-holes 56 are formed so as to oppose each other via a center line, as shown in FIG. The formation position of the through hole 56 and the formation position of the third groove 17 are located on the same plane, and the through hole 56 and the third groove 17 face each other. Thereby, the through hole 56 and the third groove 17 communicate with each other. Each of the above-described through hole 56, gap, and third groove 17 is filled with resin 57. The resin 57 is made of a silicone resin, and is located between the side surface 11 b of the first column part 11 and the facing portion 55 of the first cylinder part 51.

  The metal diaphragm 60 functions to transmit the pressure fluid pressure to the sensor element 20 via the pressure medium 16. The metal diaphragm 60 has a disk shape, and a flat surface (corrugated shape). The entire periphery of the end face of the metal diaphragm 60 facing the fixed surface 52a is welded to the annular fixed surface 52a, thereby preventing the pressure fluid from leaking to the outside.

  The ring weld 61 has an annular shape and has a flat surface. An O-ring 62 is sandwiched between the flat surface and the wall surface forming the second groove 14. With this configuration, the pressure detection chamber 15 is sealed (air-tightly sealed) by the O-ring 62. The O-ring 62 corresponds to the annular seal member described in the claims.

  Next, a method for manufacturing the pressure sensor 100 according to the present embodiment will be described. First, the first housing 10 to which the sensor element 20 is fixed and the sensor element 20 and the terminal 30 are electrically connected, and the second housing 50 to which the metal diaphragm 60 and the ring weld 61 are welded are prepared. . The above is the preparation process.

  After the preparation step, the pressure medium 16 is injected into the first groove 13 with the end portion 11a of the first housing 10 (first column portion 11) facing vertically upward, and the O-ring 62 is inserted into the second groove 14. Is provided. The above is the installation process.

  After the installation process, the first column part 11 is inserted into the hollow of the first cylinder part 51 to constitute the pressure detection chamber 15 and the pressure detection chamber 15 is surrounded by the O-ring 62. The above is the insertion process.

  After the insertion step, the end portion of the first cylinder portion 51 opposite to the second cylinder portion 52 is caulked so as to be bent toward the connecting end side of the first column portion 11 with the second column portion 12, and the caulking portion 54. Form. As a result, the first pillar portion 11 of the first housing 10 is pressed against the fixing surface 52a side, and the first housing 10 and the second housing 50 are fixed. Further, the O-ring 62 is sandwiched between the ring weld 61 and the wall surface constituting the second groove 14, and the pressure detection chamber 15 is sealed by the O-ring 62. The above is the caulking process.

  After the caulking process, resin 57 is injected into the gap through the through hole 56. The injected resin 57 first flows along the third groove 17 to the entire circumference of the first column part 11. Thereafter, the resin 57 flows into a gap positioned in a direction intersecting the annular third groove 17. As a result, the gap is filled with the resin 57, and the O-ring 62 is not exposed to the external environment. The above is the injection process.

  After the injection step, the assembled first housing 10 and second housing 50 are placed in a vacuum chamber, and thereby the gas mixed in the resin 57 is removed. The above is the degassing step.

  After the degassing step, the resin 57 is solidified. The above is the solidification process. The pressure sensor 100 according to the present embodiment is manufactured through the above steps. The above-described insertion process and caulking process are included in the assembling process described in the claims.

  Next, the function and effect of the pressure sensor 100 according to this embodiment will be described. As described above, each of the through hole 56, the gap between the side surface 11 b and the facing portion 55, and the third groove 17 is filled with the resin 57. Therefore, since the O-ring 62 is not exposed to the external environment, the deterioration of the O-ring 62 is suppressed and the leakage of the pressure medium 16 is suppressed. Further, unlike the configuration in which the gap is filled with gas, the pressure in the pressure detection chamber 15 is suppressed from increasing due to the expansion of the gas due to the increase in the external temperature. More specifically, as a result of the gas in the expanded gap flowing into the pressure detection chamber 15 via the O-ring 62 due to fluctuations in the external temperature, the generation of bubbles in the pressure detection chamber 15 is suppressed. As described above, according to the pressure sensor 100 according to the present embodiment, leakage of the pressure medium 16 due to deterioration of the O-ring 62, an increase in pressure in the pressure detection chamber 15 due to gas expansion, and gas pressure detection. Generation | occurrence | production of the bubble in the pressure detection chamber 15 by the inflow to the chamber 15 is suppressed, and the fall of the detection accuracy of the pressure resulting from these is suppressed.

  In addition, when external temperature rises, the resin 57 expand | swells similarly to gas. However, the resin 57 is located between the side surface 11 b of the first column part 11 and the facing part 55 of the first cylinder part 51, and the O-ring 62 that seals the pressure detection chamber 15 is the first column part 11. Is located in the second groove 14 formed in the end 11a. According to this, since the resin 57 and the O-ring 62 are not adjacent to each other, even if the resin 57 expands, the pressure due to the expansion is difficult to be applied to the O-ring 62, and therefore is difficult to be applied to the pressure detection chamber 15. . Thus, in this embodiment, even if the resin 57 expands, the pressure in the pressure detection chamber 15 is unlikely to fluctuate.

  In the present embodiment, two through holes 56 are formed in the facing portion 55. This makes it easier to fill the gap with the resin 57 as compared with a configuration in which one through hole is formed in the facing portion.

  In the present embodiment, the two through holes 56 are formed at equal intervals in the circumferential direction of the center line. For example, when the interval between adjacent through holes in the circumferential direction is indefinite, a place with a long adjacent interval is locally generated. In this case, it is difficult for the resin injected from the two through holes located at both ends of the place where the adjacent interval is long to reach the middle of the adjacent interval (the farthest place where the resin injected via the through hole flows). Therefore, it becomes difficult to fill the resin in the gap between the first housing and the second housing located in the middle.

  On the other hand, in the present embodiment, since the adjacent interval between the through holes 56 in the circumferential direction is constant, the distance between the middle of the adjacent intervals and the through hole 56 is also constant. According to this, it is suppressed that the flow of the resin 57 injected from the through hole 56 to the middle of the adjacent interval is difficult, and the filling of the resin 57 into the gap located in the middle is suppressed. Is done.

  In the present embodiment, an annular third groove 17 is formed on the side surface 11b of the first pillar portion 11 so as to surround the center line, and the third groove 17 and the through hole 56 communicate with each other. ing. According to this, the resin 57 can be filled in the entire circumference of the side surface 11 b along the third groove 17 without increasing the injection pressure of the resin 57. Therefore, the injection pressure of the resin 57 can be set to such an extent that the resin 57 is injected into the gap located in the direction intersecting the third groove 17. On the other hand, when there is no third groove, the resin injection pressure is such that the resin is injected into the circumferential direction of the center line and the gap located in the intersecting direction intersecting the circumferential direction. Thus, in the case of the configuration of the present embodiment, since the injection pressure of the resin 57 is lower than that in the configuration without the third groove, the resin 57 is prevented from flowing in an unexpected place.

  In the present embodiment, the injection process is performed after the caulking process. Thus, by fixing the first housing 10 and the second housing 50 before injecting the resin 57, the fixing position of the first housing 10 and the second housing 50 by the injection pressure of the resin 57. The occurrence of problems such as slippage or leakage of the pressure medium 16 is suppressed.

  In this embodiment, the degassing process is performed after the injection process. According to this, as a result of the gas mixed in the resin 57 expanding and contracting, it is possible to suppress an excessive pressure from being applied to the pressure detection chamber 15.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  In this embodiment, the example in which the two through-holes 56 were formed in the opposing part 55 was shown. However, the number of through-holes 56 is not limited to the above example, and for example, a configuration in which six through-holes 56 are formed in the facing portion 55 can be employed. In the case of this configuration, for example, the three through holes 56 are used as through holes for injecting the resin 57, and the remaining three through holes 56 are used as through holes for removing the gas in the gap. Is easy to rotate and filling becomes easy. However, also in the case of the said modification, the through-hole 56 has the preferable structure formed in the circumferential direction of the centerline at equal intervals.

  In this embodiment, the example which performed the injection | pouring process after the caulking process was shown. However, the injection process may be performed after the insertion process, and the caulking process may be performed after the injection process.

  Although a specific configuration is omitted, a gas vent hole for venting the gas mixed in the resin 57 may be formed in the first pillar portion 11.

DESCRIPTION OF SYMBOLS 10 ... 1st housing 17 ... 3rd groove | channel 20 ... Sensor element 30 ... Terminal 50 ... 2nd housing 56 ... Through-hole 57 ... Resin 100 ... Pressure sensor

Claims (10)

A pressure sensor formed by combining a first housing to which a sensor element and a terminal are fixed, and a second housing having a metal diaphragm;
The second housing has a cylindrical shape, and the hollow thereof is divided by the metal diaphragm into an accommodation space for accommodating the first housing and an introduction space for introducing a pressure fluid to be detected,
The first housing has a columnar shape, a first groove provided with the sensor element and a part of the terminal, and a second seal member provided with an annular seal member at an end on the metal diaphragm side. A groove is formed, and the entire circumference of the first groove is surrounded by the second groove,
A pressure detection chamber is constituted by the first groove and the metal diaphragm,
The pressure detection chamber is filled with a pressure medium that transmits the pressure fluid pressure acting on the metal diaphragm to the sensor element;
An end of the second housing on the accommodation space side is caulked with respect to the first housing, and the caulked portion causes the first housing to pass through the seal member and the second housing. It is pressed against the fixed part of the metal diaphragm,
At least one through-hole that communicates the housing space with the outside is formed in a portion of the second housing that divides the housing space and is opposed to a side surface of the first housing.
A gap between the side surface of the first housing and the facing portion of the second housing, which is a part of the housing space and is separated from the pressure detection chamber by the seal member, is interposed through the through hole. A pressure sensor characterized by being filled with injected resin. A plurality of the through holes are formed in the second housing;
At least one of the plurality of through holes is a through hole for injecting resin into the gap,
The pressure sensor according to claim 1, wherein at least one of the plurality of through holes is a through hole for extracting gas from the gap.   3. The pressure sensor according to claim 2, wherein the plurality of through holes are formed at equal intervals along a circumferential direction of a central axis of the second housing. An annular third groove surrounding the central axis of the first housing is formed on the side surface of the first housing,
The pressure sensor according to claim 1, wherein the third groove communicates with the through hole. The first housing is connected to a first pillar portion provided in the hollow of the second housing, and an end portion of the first pillar portion away from the metal diaphragm, and is exposed from the second housing. And
The diameter of the first column part is longer than the diameter of the second column part,
The end on the first housing side of the second housing is caulked so as to be bent toward the end of the first pillar portion away from the metal diaphragm. The pressure sensor according to item. It is a manufacturing method of the pressure sensor according to any one of claims 1 to 5,
An assembly step of assembling the first housing and the second housing;
An injection step of filling the gap with the resin by injecting resin into the gap between the side surface of the first housing and the facing portion of the second housing through the through hole after the assembly step; The manufacturing method of the pressure sensor characterized by having.   The assembling step includes an inserting step of inserting the first housing into the hollow of the second housing, and a caulking step of caulking an end portion of the second housing on the first housing side after the inserting step. The method of manufacturing a pressure sensor according to claim 6.   8. The degassing process according to claim 7, further comprising a degassing step of degassing the gas mixed in the resin by placing the fixed first housing and the second housing in a vacuum chamber after the injecting step. A manufacturing method of a pressure sensor.   The method of manufacturing a pressure sensor according to claim 6, wherein the assembly step is an insertion step of inserting the first housing into the hollow of the second housing. After the injecting step, performing a caulking step for caulking the end of the second housing on the first housing side,
The method according to claim 9, further comprising a degassing step of removing gas mixed in the resin by placing the fixed first housing and the second housing in a vacuum chamber after the caulking step. A manufacturing method of a pressure sensor.

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