JP2002039901A - Pressure sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve the constitution of an easily processable housing, in a pressure sensor, constituted by attaching the housing of which an opening for introducing a pressure medium has a projection to a pipe member, through which the pressure medium flows and pushing the pressure introducing pin of the pipe member by the projection, to introduce the pressure medium in the pipe member into a pressure detection part from the opening. SOLUTION: The projection 15 is formed separately from the housing 7 by press processing or the like and inserted in the opening 7b of the housing 7 to be fixed thereto. The end of the projection 15 pushes the pin 201 of the pipe member 200, and the pressure medium in the pipe member 200 is introduced into the pressure detection part 14 from a through-hole 202 through the hole part formed to the side surface of the projection 15. Since the projected part formed integrally along with the housing heretofore is processed separately from the housing, the processing of the housing is facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-introducing housing in which a housing having a projection at an opening for introducing a pressure medium is attached to a pipe member through which the pressure medium flows. The pressure sensor is adapted to introduce a pressure medium in the pipe member from the opening to the pressure detecting section by pressing the pin, and is suitably used, for example, as a sensor for detecting a refrigerant pressure for an air conditioner.

[0002]

2. Description of the Related Art FIG. 5 shows a schematic sectional view of an O-ring sealed type pressure sensor for detecting a refrigerant pressure for an air conditioner as a conventional general pressure sensor. In this device, a pressure detection chamber 10 is formed by assembling a connector case 3 containing a connector pin 4 and a metal housing 7 including a seal diaphragm 8.
The sensor element (integrated element) 1 fixed to the pedestal 2 is accommodated in the inside of the pedestal 2.

The pressure detecting chamber 10 is filled with an oil 11 for transmitting pressure from the seal diaphragm 8. An O-ring 12 housed in a groove (O-ring groove) formed on an end face of the connector case 3 is provided around an outer periphery of the pressure detection chamber 10 with a metal holding member 9 which is a part of the housing 7 and a connector case. 3 and the pressure detection chamber 1 is provided by the O-ring 12.
0 is hermetically sealed. Thus, these pressure detection chambers 1
0, sensor element 1, seal diaphragm 8, oil 11
Is configured as the pressure detection unit 14.

In this pressure sensor, an opening 7b for introducing a refrigerant for an air conditioner as a pressure medium is formed in the housing 7, and inside the opening 7b cutting and cooling are performed integrally with the housing 7. Protrusion 3 by forging etc.
00 and a hole 301 are formed. The pressure sensor is attached by, for example, screwing the housing 7 to the pipe member 200 through which the refrigerant flows.

[0005] Here, the refrigerant flows through the inside of the pipe member 200, and a pin as an opening / closing means for introducing the refrigerant inside the pipe member 200 to the pressure sensor is generally provided at a portion where the housing 7 is attached. 201 is provided. The pin 201 utilizes, for example, an elastic force of a spring or the like, and is in a closed state when no pressure sensor is attached.

Then, as shown in FIG. 5, when the housing 7 is attached to the pipe member 200, the projection 300
01, the inside of the tube member 200 and the opening 7b of the housing 7 communicate with each other, and the refrigerant in the tube member 200 passes through the hole 301 from the opening 7b and passes through the pressure detecting unit 14.
Is introduced to The pressure of the introduced refrigerant is transmitted to the oil 11 received and sealed by the seal diaphragm 8, and the pressure of the oil 11 is detected by the sensor element 1,
An electric signal proportional to the pressure is output.

[0007]

However, in the conventional pressure sensor described above, the pin 2 of the pipe member 200 is not provided.
The processing of the projection 300 and the hole 301 for pressing 01
Although it is performed by cold forging, cutting, or the like, such detailed processing cannot be easily performed, and is troublesome.

In view of the above problems, the present invention attaches a housing having a projection at an opening for introducing a pressure medium to a pipe member through which the pressure medium flows, and the projection for pressure introduction provided on the pipe member. An object of the present invention is to realize a configuration of a housing that can be easily processed in a pressure sensor in which a pressure medium in a pipe member is introduced from an opening to a pressure detecting unit by pushing a pin.

[0009]

To achieve the above object, according to the first aspect of the present invention, a pin (20) as an opening / closing means for introducing a pressure medium flowing through the inside to a pressure sensor is provided.
A housing (7) attached to the pipe member (200) having the above (1) and having an opening (7b) for introducing a pressure medium, a projection (15) provided in the opening of the housing; The provided pressure detector (1
4) when the housing is attached to the pipe member,
In a pressure sensor in which a projection presses a pin to introduce a pressure medium in a pipe member from an opening to a pressure detection unit, the projection is formed separately from the housing and attached to the housing. It is characterized by being.

According to the present invention, since the projection formed integrally with the housing is provided separately from the housing and attached to the housing, the projection is formed on the housing by cutting, cold forging, or the like. There is no need to perform this, and a housing configuration that can be easily machined can be realized.

Here, the projection (15) may be formed by press working (the invention of claim 2), or may be press-fitted into the opening (7b) of the housing (7) and fixed (claim). According to the third aspect of the invention), the projection can be easily formed.

In the invention according to claim 4, the protrusion (1)
5) has a hole (1) for introducing the pressure medium in the pipe member (200) from the opening (7b) to the pressure detecting unit (14).
5c) is formed. According to this, since the hole is provided integrally with the projection, the configuration can be simplified.

Here, according to the invention of claim 5, the protrusion (1)
5) pushes the pin (201) at the tip (15a), and the hole (15c) is formed on the side surface of the projection. Protrusions with appropriately formed holes are provided at portions other than the pressed portion.

The reference numerals in parentheses of the above means are examples showing the correspondence with specific means described in the embodiments described later.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention. FIG. 1 is a cross-sectional view schematically showing an entire pressure sensor 100 according to an embodiment of the present invention. In addition,
The same parts as those in FIG. 5 are denoted by the same reference numerals in FIG.

In this embodiment, although not limited, the pressure sensor 100 is attached to the pipe member 200 through which the refrigerant (pressure medium) of the air conditioner flows,
It is applied to detect the refrigerant pressure in 00. In FIG. 1, the pressure sensor 100 is connected to the pipe member 20.
0 is shown.

A sensor element (integrated sensor element) 1 made of a semiconductor or the like for converting a pressure signal into an electric signal is anodically bonded to a pedestal 2 made of glass, and an adhesive such as silicon rubber is attached to a concave portion of the connector case 3. It is fixed at. In this example, the connector case 3 is formed by resin molding (injection molding).
It is a stepped cylindrical shape made by
A connector pin 4 for outputting an electric signal is integrally formed and held by insert molding.

The connector case 3 has a connecting portion 3a at one end of the shaft (upper side in FIG. 1) for electrically connecting one end of the connector pin 4 to an external circuit via, for example, a wire harness. . In a recess formed at the other end of the shaft of the connector case 3 (the lower side in FIG. 1), the other end of the connector pin 4 is sealed with an interface sealant 5 such as silicone rubber.

In the recess of the connector case 3,
The sensor element 1 is electrically connected to the other end of the connector pin 4 via a bonding wire 6 formed by wire bonding or the like, and an electric signal from the sensor element 1 is transmitted from the bonding wire 6 via the connector pin 4. Thus, it is transmitted to the external circuit.

The housing 7 has an opening 7b as a pressure introduction hole into which a refrigerant (pressure medium) is introduced and a pressure sensor 10
A metal body (for example, plated with carbon steel) having a screw portion 7c for fixing O to the pipe member 200 is provided. Further, the housing 7 includes a seal diaphragm 8 made of a thin metal (for example, SUS) and a holding member (ring weld) made of metal (for example, SUS).
9 is entirely welded to the main body 7a and hermetically joined to one end of the opening 7b.

The connector case 3 and the housing 7 are assembled and fixed by a method such as caulking, and a pressure detection chamber 10 is provided between the recess of the connector case 3 and the seal diaphragm 8 of the housing 7. It is configured. The pressure detecting chamber 10 is filled with an oil 11 which is a pressure transmitting medium and a filling liquid, and forms a liquid sealing structure by the seal diaphragm 8 and the interface sealant 5.

Further, an O-ring 12 made of an elastic material such as Si (silicon) rubber is formed around the outer periphery of the pressure detection chamber 10 so that the O-ring 12 of the pressure detection chamber 10 is formed on the end surface of the connector case 3 on the concave side (one end of the shaft). It is housed and arranged in an annular groove (O-ring groove) 13 formed in a portion located on the outer periphery. Thereby, the airtightness of the pressure detection chamber 10 is ensured, and the seal of the oil 11 is ensured.

In the pressure sensor 100, a portion located on the inner peripheral side of the O-ring 12, ie, the pressure detection chamber 1
0, sensor element 1, seal diaphragm 8, oil 11
Is configured as the pressure detection unit 14.

In the pressure sensor 100,
A projection (ring weld) 15 formed separately from the housing 7 and attached to the housing 7 is provided in an opening 7 b formed in the housing 7. FIG.
FIGS. 3A and 3B are configuration diagrams of the protrusion 15 alone, FIG. 4A is a view as viewed from the front end side in the protrusion direction of the protrusion 15, and FIG.
It is AA sectional drawing in a middle.

The protruding portion 15 has a cup-like shape in which a tip portion 15a is a closed portion, and an end portion opposite to the tip portion 15a is an opening. The extended umbrella portion 15b is configured. Also, the protrusion 1
A hole 15 c penetrating through the side surface of the protrusion 5 is formed on the side surface of the protrusion 5 so as to communicate the inside and outside of the protrusion 15. Although two holes 15c are formed in this example, one hole or three or more holes may be provided.

The projection 15 is made of stainless steel (SUS)
After a hole corresponding to the hole 15c is formed in a metal plate such as that described above, it can be formed by pressing. Assembling of the projection 15 to the housing 7 is performed by press-fitting as shown in FIG. That is, the projection 15 and the housing 7 are set on the jig K (FIG. 3A), and the projection 15 is pressed into the opening 7b of the housing 7 by hand press (FIG. 3B).

By this press-fitting, the protruding portion 15 is fixed in contact with the side surface of the opening 7b of the housing 7 at the umbrella portion 15b. That is, the umbrella portion 15b is
Is formed as a contact portion which is fixed by being brought into contact with the opening 7b when it is press-fitted into the opening 7b.

Then, as shown in FIG.
The housing 7 provided with the screw member 7
c is screw-coupled. Here, FIG. 4 schematically shows an enlarged cross section near the mounting portion of the housing 7. FIG.
3A shows a state in which the housing 7 is attached to the pipe member 200, and FIG.
Indicates a state in which it is not attached to.

The coolant flows through the inside of the pipe member 200, and a pin 201 as an opening / closing means for introducing the coolant inside the pipe member 200 to the pressure sensor is provided at a portion where the housing 7 is attached. ing. As shown in FIG. 4, the pin 201 is inserted into a through-hole 202 penetrating the pipe member 200 and has umbrella portions at both ends.

FIG. 4B shows a state in which the umbrella portion of the pin 201 inside the pipe member 200 closes the through hole 202 and the refrigerant in the pipe member 200 does not leak to the outside (closed state). is there. On the other hand, the state shown in FIG. 4A is a state (open state) in which the umbrella portion of the pin 201 on the inner side of the tube member 200 has opened the through hole 202 and the refrigerant in the tube member 200 leaks to the outside. .

That is, when the housing 7 is attached to the tube member 200, the tip 15a of the projection 15
Push the pin 201 into the pipe member 200 (FIG. 4).
(In the direction of the outlined arrow in (b)) to push the pin 201
Changes from the closed state in FIG. 4B to the open state in FIG. When the pressure sensor 100 is detached from the pipe member 200, the pin 201
Restores the closed state of FIG.

Therefore, when the housing 7 is attached to the pipe member 200, the projection 15 pushes the pin 201, and as shown by the arrow B in FIG. The refrigerant (pressure medium) in the pipe member 200 is introduced into the pressure detecting section 14 through the section 15c.

The pressure of the introduced refrigerant is received by the seal diaphragm 8 and transmitted to the oil 11 sealed in the pressure detection chamber 10. The pressure of the oil 11 is detected by the sensor element 1, and the sensor element 1 outputs an electric signal proportional to the pressure. This output signal is transmitted from the bonding wire 6 to the external circuit via the connector pin 4.

Next, the process of assembling the pressure sensor 100 will be schematically described. The pedestal 2 and the sensor element 1 are arranged in the recess of the connector case 3 formed by injection. After connecting the sensor element 1 and the connector pin 4 with the bonding wire 6, the O-ring 12 is arranged inside the groove 13. Then, with the sensor element 1 side of the connector case 3 facing upward, a predetermined amount of oil 11 is injected from above the concave portion of the connector case 3 using a dispenser or the like.

Then, the housing 7 provided with the seal diaphragm 8 and the projection 15 is lowered from the top so as to fit into the connector case 3 while keeping the horizontal state from above, and the end face of the connector case 3 on one end side of the shaft and the housing 7. Of the housing 7 until the holding member 9 is sufficiently in contact with the holding member 9.
d is fixed around the entire circumference. Thus, the connector case 3 and the housing 7 are assembled, and the pressure detection chamber 10 is formed.

When the connector case 3 and the pressing member 9 are pressed until they come into sufficient contact, the pressing member 9 simultaneously presses the O-ring 12 while covering the groove 13. As a result, the oil 1
1 is secured. Thus, the O-ring 12 is sandwiched between the connector case 3 and the housing 7, and the pressure detection chamber 10 is sealed around its outer periphery. Thus, the pressure sensor 100 shown in FIG. 1 is completed, and is attached to the pipe member 200 to perform pressure detection as described above.

By the way, according to the present embodiment, the projection formed integrally with the housing is replaced with the housing 7.
Since it is separate from and attached to the housing 7, there is no need to form a projection on the housing 7 by cutting, cold forging, or the like. Therefore, according to the present embodiment,
In the pressure sensor 100, a configuration of the housing 7 that can be easily processed can be realized.

If the projections 15 are formed by press working as in this example, they can be easily formed. Further, in this example, since the projection 15 can be easily assembled to the housing 7 simply by press-fitting into the opening 7 b of the housing 7, the projection 15 can be easily provided on the housing 7.

The hole for introducing the refrigerant in the pipe member 200 from the opening 7b to the pressure detector 14 is
5 may be formed separately from the housing 7, but in the present embodiment, as a more preferable form, the protrusion 15 has the hole 1.
5c is integrally provided and the configuration can be simplified.

Here, in the present embodiment, the projections 15
Since the pin 201 is pressed by the tip 15a, and the hole 15c is formed on the side surface of the protrusion 15,
In the part other than the part which pushes the pin 201 among the protrusion parts 15,
A configuration in which the hole 15c is appropriately formed can be provided.

As described above, according to the present invention, the housing having the projection at the opening for introducing the pressure medium is attached to the pipe member through which the pressure medium flows, and the projection is provided with the projection at the pipe member. The main feature of the pressure sensor in which the pressure medium in the pipe member is introduced from the opening to the pressure detection unit by pressing the pin for The design of the part can be changed as appropriate.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing an entire pressure sensor according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a projection unit alone in FIG. 1;

FIG. 3 is an explanatory view showing a method of assembling a projection to a housing.

FIGS. 4A and 4B are schematic diagrams showing an enlarged cross section near a mounting portion of the housing to the pipe member, wherein FIG. 4A shows a state where the housing is mounted on the pipe member, and FIG. Indicates a state that has not been performed.

FIG. 5 is a schematic sectional view of a conventional general pressure sensor.

[Explanation of symbols]

7 housing, 7b opening, 14 pressure detector, 1
5 Projection, 15a Projection tip, 15c Hole
200: tube member, 201: pin.

Claims (5)

[Claims] An opening (7b) attached to a pipe member (200) having a pin (201) as an opening and closing means for introducing a pressure medium flowing through the inside to a pressure sensor, and for introducing the pressure medium. (7) with housing
And a projection (1) provided at the opening of the housing.
5) and a pressure detection unit (14) provided in the housing, wherein when the housing is attached to the pipe member, the protrusion presses the pin, thereby causing the pressure detection unit to pass through the opening. In a pressure sensor adapted to introduce a pressure medium in the pipe member, the projection is formed separately from the housing and attached to the housing. 2. The pressure sensor according to claim 1, wherein the projection is formed by press working. 3. The projection (15) is provided with the opening (7).
3. The pressure sensor according to claim 1, wherein the pressure sensor is press-fitted into b) and fixed. 4. The pipe member (2) is connected to the protrusion (15) from the opening (7b) to the pressure detector (14).
The pressure sensor according to any one of claims 1 to 3, wherein a hole (15c) for introducing a pressure medium in the (00) is formed. 5. The projection (15) has a tip (1).
The pressure sensor according to claim 4, wherein the pin (201) is pressed at 5a), and the hole (15c) is formed in a side surface of the protrusion.