JP2003050172A - Pressure detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly and easily mount the diaphragm at a support member made or a metal and having a through-hole, irrespective of the difference of the plate thicknesses of the member and the diaphragm made of a metal covering other end side of the hole in a pressure detector, having a semiconductor pressure sensor containing a semiconductor pressure sensitive element in a housing having a pressure input tube engaged liquid tightly with the through hole of the member from its one end side and mounting at the member, the diaphragm mounted at the member, facing one surface of the diaphragm and a pressure-receiving chamber formed in the housing, filled with a liquid-like medium. SOLUTION: The pressure detector comprises the support member 7, the diaphragm 12, and a holding member 14 for holding a peripheral edge of the diaphragm 12 in between the member 14 and the member 7, in such a manner that the outer periphery of the member 14 is coupled to an outer periphery of the member 7 by caulking.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal support member having a through-hole and a pressure-introducing pipe which is fitted into the through-hole from one end thereof in a liquid-tight manner. A semiconductor pressure sensor having a semiconductor pressure-sensitive element built therein is mounted in a housing having a metal diaphragm that covers the other end of the through-hole, and the support member and the support member are disposed facing one surface of the diaphragm. The present invention relates to an improvement in a pressure detecting device in which a pressure receiving chamber formed in the housing is filled with a liquid medium. 2. Description of the Related Art Such a pressure detecting device has been conventionally used to prevent a corrosive pressure medium from directly touching a semiconductor pressure-sensitive element of a semiconductor pressure sensor, and a metal diaphragm is used. Is generally attached to the support member by laser welding. However, in the above-described conventional diaphragm mounting structure by laser welding,
If the thickness of the diaphragm is different from the thickness of the support member at the diaphragm attachment portion, it is difficult to perform good laser welding. SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a pressure detecting device capable of attaching a diaphragm to a support member satisfactorily and easily despite the difference in plate thickness between the support member and the diaphragm. The purpose is to provide. [0005] In order to achieve the above object, the present invention is directed to a pressure supporting member which is liquid-tightly fitted into a metal supporting member having a through hole from one end side of the through hole. A semiconductor pressure sensor including a semiconductor pressure-sensitive element is mounted in a housing having an introduction pipe, and a metal diaphragm that covers the other end of the through hole is mounted.
In a pressure detection device in which a liquid medium is filled into a pressure receiving chamber formed in the support member and the housing with one surface of the diaphragm facing the outer peripheral portion of the support member,
An outer peripheral portion of a holding member for holding the peripheral portion of the diaphragm between the supporting member and the supporting member is swaged and connected. According to such a configuration, a metal diaphragm for preventing the pressure medium from directly touching the semiconductor pressure-sensitive element is provided by a caulking connection of the holding member to the supporting member. The diaphragm is attached to the supporting member so that the outer peripheral portion is sandwiched between the diaphragm and the diaphragm, and even if the thickness of the supporting member at the diaphragm mounting portion is different, the diaphragm can be satisfactorily and easily attached to the supporting member. It can be mounted. An embodiment of the present invention will be described below with reference to an embodiment of the present invention shown in the accompanying drawings. Referring to FIG. 1 showing an embodiment of the present invention, this pressure detecting device uses a semiconductor pressure sensor 1 to apply a pressure of a corrosive pressure medium to a semiconductor pressure-sensitive element 2 provided in the semiconductor pressure sensor 1. And is attached to a tank (not shown) for storing the pressure medium, a pipe (not shown) through which the pressure medium flows, and the like. The semiconductor pressure sensor 1 includes a housing 3 formed of a synthetic resin and having a pressure introducing pipe 3a and a semiconductor pressure-sensitive element 2 built therein. The terminals 4, 4... Penetrate the housing 3 in a liquid-tight manner and protrude out of the housing 3. Moreover, the outer ends of the terminals 4, 4,... Are connected to a substrate 5 which is separate from the housing 3, and the substrate 5 is provided with a processing circuit 6 for processing signals output from the semiconductor pressure sensor 1. The semiconductor pressure sensor 1 is mounted on a support member 7. The support member 7 includes a disk 7a and a disk 7a.
Formed integrally with, for example, a metal such as brass, integrally having a cylindrical portion 7b coaxially protruding from the center of one end and a flange portion 7c extending radially outward from the outer periphery of the other end of the disk portion 7a. In the center of the support member 7, a through hole 8 is provided. A large-diameter hole 8a is formed at one end of the through-hole 8, and the pressure introducing pipe 3a provided in the housing 3 of the semiconductor pressure sensor 1 is located between the inner surface of the large-diameter hole 8a. One end of the through hole 8 is liquid-tightly fitted into the through hole 8 with a ring-shaped seal member 9 interposed therebetween. The housing 3 in which the pressure introducing pipe 3a is fitted into the through hole 8 is brought into contact with the distal end of the cylindrical portion 7b, and the housing 3 in that state is engaged with the housing 3 from the side opposite to the supporting member 7, for example, a pair of engaging members The joining members 10, 10 are screw members 11,
At 11, it is fastened to one end of the disk part 7a. Thus, the semiconductor pressure sensor 1 is attached to the support member 7 such that the housing 3 is sandwiched between the cylindrical portion 7b and the pair of engagement members 10, 10. At the other end of the support member 7, a diaphragm 1 made of metal, for example, stainless steel, covering the other end of the through hole 8 is provided.
The pressure receiving chamber 1 is formed in the support member 7 and the housing 3 with one surface of the diaphragm 12 facing.
3 is filled with a liquid medium such as silicone oil. The outer peripheral portion of the other end of the support member 7, that is, the flange portion 7
c, the entire periphery of the holding member 14 formed of a metal such as stainless steel in the shape of a dish facing the other surface of the diaphragm 12 is disposed between the supporting member 7 and the periphery of the holding member 14. It is caulked so as to be clamped. In clamping the peripheral edge of the diaphragm 12, the flange 7c of the support member 7 and the clamping member 14
Nipping projections 7d, 1 formed in a ring shape corresponding to each other
4a are protruded, and the periphery of the diaphragm 12 is sandwiched between the sandwiching projections 7d and 14a. A ring-shaped sealing member 15 is sandwiched between the diaphragm 12 and the flange 7c on the outer side of the holding projections 7d and 14a, and a ring-shaped sealing member is provided between the diaphragm 12 and the holding member 14. The peripheral portion of the diaphragm 12 is sandwiched between the flange portion 7c of the support member 7 and the outer peripheral portion of the sandwiching member 14 so that the sealability is maintained by the seal members 15 and 16. At the center of the holding member 14, the diaphragm 1
A connecting cylinder portion 14b protruding on the opposite side to the second cylindrical member 2 is integrally connected. In order to attach the connecting cylinder portion 14b to a tank for storing the pressure medium, a pipe through which the pressure medium flows, or the like,
For example, the cap nut 17 is connected. The cap nut 17 is connected to the connecting cylinder 14b.
End wall 17 in which an insertion hole 18 for inserting
The engaging portion 14c formed by bending the tip of the connecting cylinder portion 14b inserted through the insertion hole 18 in the cap nut 17 engages with the inner surface of the end wall 17a, so that the cap nut 17 is formed. Is connected to the connecting cylinder 14c. In addition, in the cap nut 17, the connecting cylindrical portion 14 inserted through the insertion hole 18 is provided.
A ring-shaped seal member 19 sandwiched between a tip portion of c and a member screwed to the cap nut 17 is housed. According to such a pressure detecting device, the outer peripheral portion of the metal diaphragm 12 for preventing the pressure medium from directly touching the semiconductor pressure-sensitive element 2 is caulked to the support member 7 of the holding member 14. By the connection, the support member 7 and the holding member 14 are sandwiched. Therefore, even if the thickness of the diaphragm 12 is different from the thickness of the support member 7 at the diaphragm mounting portion, the diaphragm 12 can be mounted on the support member 7 satisfactorily and easily. Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various design changes can be made without departing from the present invention described in the appended claims. It is possible. As described above, according to the present invention, it is possible to attach the diaphragm to the support member satisfactorily and easily despite the difference in the plate thickness between the support member and the diaphragm.

[Brief description of the drawings] FIG. 1 is a longitudinal sectional view of a pressure detecting device. [Explanation of symbols] 1 ... Semiconductor pressure sensor 2 ... Semiconductor pressure-sensitive element 3 ... Housing 3a ... pressure introduction pipe 7 ... Support member 8 ... Through-hole 12 ・ ・ ・ Diaphragm 13 ・ ・ ・ Pressure receiving chamber 14 ... Nipping member

Claims (1)

1. A pressure introducing pipe (3a) which is liquid-tightly fitted into a metal support member (7) having a through hole (8) from one end side of said through hole (8). ) With housing (3)
A semiconductor pressure sensor (1) having a semiconductor pressure-sensitive element (2) built therein is mounted therein, and a metal diaphragm (12) for covering the other end of the through hole (8) is mounted thereon. (12) In a pressure detection device in which a liquid medium is filled in a pressure receiving chamber (13) formed in the support member (7) and the housing (3) with one surface facing the surface of the support member (7). A pressure detecting device, wherein an outer peripheral portion of a clamping member (14) for clamping a peripheral portion of the diaphragm (12) between the outer peripheral portion and the support member (7) is caulked.