JPH0726674Y2 - Pressure detector - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure detecting device, and in particular, a sensor unit and a pressure introducing part communicating with a pressure introducing port of the sensor unit are housed in a resin case, and parts inside the case are made of potting resin. The present invention relates to the structure of a pressure detecting device adapted to be molded.

[0002]

BACKGROUND OF THE INVENTION The applicant of the present application has found that the potting resin sealed inside a pressure detection device and the resin member such as a case constituting the pressure detection device is peeled off due to a difference in coefficient of thermal expansion to the inside. In view of water invasion, there has been previously proposed a structure in which the electrical connection part of the sensor unit and the pressure introducing component for guiding the external pressure to the pressure introducing port of the sensor unit are separately configured.

FIG. 6 is a sectional view showing a pressure sensor structure as the prior art. The case 1 is made of resin and has a container shape that opens upward, and a plurality of connector pins 11 (one of which is shown) are penetratingly embedded in a thick wall protruding laterally to form a connector 12. A pressure sensor unit 2 incorporating a known semiconductor sensor is positioned and housed in the case 1.

A case 1 accommodating a pressure sensor unit 2
The wiring board 3 made of a resin plate having a constant thickness
Are placed. A lead frame (not shown) of a predetermined shape is embedded and fixed in the wiring board 3, and the lead frame is exposed at a notch or a hole at an appropriate position so that it projects from the connector pin 11 and the metal case of the unit 2. The output terminal is electrically connected.

A pressure introducing component 4 made of resin is inserted from the wiring board 3 to the case opening 13 side, and the insertion end portion 40 thereof is inserted.
Has a large-diameter plate shape, and the outer peripheral surface is located near the inner wall of the case of the opening 13. A pressure introducing path 41 is formed in the cylinder of the pressure introducing component 4 and is hermetically connected to the pressure introducing port 21 of the unit 2 extending through the wiring board 3 and the O-ring 5. There is. As a result, the external pressure introduced through the pressure introducing passage 41 is guided to the pressure sensor element portion in the unit 2 without leaking, and the pressure is detected. The end 40 of the pressure sensor unit 2, the wiring board 3, the pressure introducing component 4 and the O-ring 5 which are housed in the case 1 are molded and fixed by the injected potting resin to protect the functional components and joints. To be

[0006]

In the pressure sensor having the above structure, when the potting resin 6 is injected into the case 1 through the case opening 13, the air between the storage parts, the gas produced by the reaction product of the potting resin, etc. Tries to escape to the upper part (case opening 13). At this time, the pressure introducing component 4 acts like a lid against the gas that is about to come out, and the potting resin 6, especially the pressure introducing component 4
Gas is likely to remain inside the potting resin layer 61 set between the end portion 40 and the wiring board 3, and the sealing property of the O-ring 5 is hindered, or water is accumulated due to thermal stress, resulting in a significant decrease in reliability. There was a problem of letting it. Further, in terms of manufacturing, there is a problem that it takes time to inject the potting resin and the amount of potting resin is not constant.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a pressure detecting device capable of preventing gas from remaining inside when a potting resin is injected.

[0008]

The structure of the present invention will be described. A pressure detecting device includes a case having one opening, a pressure sensor unit housed in the case, and an insertion arrangement through the case opening. A pressure introducing part that has a pressure introducing path that is airtightly connected to a pressure introducing port that extends from the pressure sensor unit and that has an insertion side end portion that is approximately the same size as the opening of the case, A potting resin to be molded, and at the insertion side end of the pressure introducing component, a through hole is provided in the vicinity of the outer peripheral portion thereof, and from this through hole to the pressure introducing port of the pressure introducing path. A conical taper portion is provided so that the end surface of the insertion side end portion projects toward the pressure sensor unit in the case toward the connecting portion.

[0009]

In the above-mentioned structure, the pressure sensor unit and the pressure-introducing component at the end portion on the insertion side are housed in the case, and when the potting resin is poured into the case through the case opening, each housing is housed. The air between the components or the gas produced by the reaction product of the potting resin is guided to the through hole along the tapered portion of the end face of the insertion side end of the pressure introducing component, and is discharged to the outside from the case opening.

Therefore, according to the pressure detecting device of the present invention, it is possible to effectively prevent the problem that the gas remains inside when the potting resin is injected.

[0011]

1 shows an example of a pressure sensor device according to the present invention. FIG. 1A is a structural view showing a cross-section of a main part of the apparatus, and FIG. 1B is a view taken in the direction of arrow A in FIG. The basic structure is the same as that of the conventional example already described, and the same components are designated by the same reference numerals. The difference will be mainly described below.

Similar to the prior art example shown in FIG. 6, the pressure sensor unit 2 incorporating the pressure sensor element portion is housed in the case 1. The unit 2 includes a wiring board 3 and a case 1
Are electrically connected to the connector pins 11 of the connector section 12. The pressure introducing component 4 is connected to the pressure introducing port 21 of the unit 2 via an O-ring 5. And
The pressure sensor unit 2, the wiring board 3, the pressure introducing component 4, and the O-ring 5 are fixed and protected by the potting resin 6 in the case 1.

In this structure, when the potting resin 6 is injected into the case 1 from the pressure introducing component 4 side, as described above, the air between the storage components or the gas produced by the reaction product of the potting resin is in the upper part (the case opening 1).
Trying to get out to 3). Here, the pressure introducing component 4
As shown in FIG. 5, the taper 42 that protrudes like an umbrella up to the gas vent hole 43 that is set in the vicinity of the peripheral edge with the groove 45 position where the O-ring is housed in the insertion end 40 as the apex.
Is attached. Therefore, at the time of assembling the pressure introducing component 4 into the case and injecting the potting resin, the umbrella-shaped taper 42 faces downward, and as shown in FIG. 2, the gas contained in the potting resin layer 61 is smoothly degassed from the case. It can escape through the hole 43. Further, the gas accumulated in the groove 45 formed in the pressure introducing component 4 for setting the O-ring 5 is also attached to the umbrella-shaped taper 4
The gas guiding groove 44 formed along the groove 2 allows the gas to be extracted upward through the gas vent hole 43 without remaining.

In FIG. 1A, reference numeral 46 denotes a step portion provided on the pressure introducing component 4, which is a pressure introducing component 4.
The component 4 is made thicker at the base of the mounting hose (not shown) connected to the mounting hose, so that even if peeling occurs at the interface between the base of the component 4 and the potting resin 6, the mounting hose and pressure Water droplets such as rainwater attached to the gap between the sensor and the sensor will be collected in the corner portion formed by the step portion 46, and it is possible to prevent water from easily entering through the potting resin peeling portion.

Next, the pressure sensor device of the above embodiment will be described according to its assembling process. FIG. 3 is an exploded view of the pressure sensor device shown in FIG. The pressure sensor unit 2 and the wiring board 3 are set with the case 1 on the component assembly side, that is, with the opening 13 facing upward. Then, the lead pin 22 led out from the metal flange portion of the pressure sensor unit 2 via the feedthrough capacitor, the lead frame 31 arranged in the wiring board 3, the connector pin 11 of the case 1 and the lead frame 31 of the wiring board 3. Each is caulked and electrically connected by welding or soldering. Next, pressure introducing parts 4
The O-ring 5 is set in the groove 45 formed in the above, and the pressure introduction port 21 of the unit 2 and the O-ring 5 are assembled in the case 1 in which the above-mentioned assembly is completed. At this time, the insertion end 40 of the pressure introducing component 4 has an umbrella-shaped taper 42, a gas vent hole 43, and a gas guide groove 4 as shown in FIG.
4 are provided. If the above assembly is completed,
As shown in FIG. 4, finally, a potting resin injection nozzle 60 is inserted into the case 1 using a part of the gas vent hole 43, and the potting resin 6 is placed on the upper surface of the case 1 (opening 13).
Inject and cure. It should be noted that, although the injection is usually performed under the atmospheric pressure or the negative pressure atmosphere, in any case, the umbrella-shaped taper 42, the gas vent hole 43, and the gas guide groove 44 of the present embodiment can exert the above-described effects. it can.

As described above, the structure of the pressure sensor device of this embodiment makes it possible to prevent residual gas in the potting resin in the pressure sensor in which the wiring board 3 and the pressure introducing component 4 are separated. Since the degassing at the time of injecting the potting resin becomes easy, the resin injecting time can be reduced by about 20% as compared with the structure shown in FIG.

In the above embodiment, the wiring board 3
Although the description has been made by taking as an example the case where the pressure-introducing component 4 and the pressure-introducing component 4 are separated and used as separate members, the point is that a pressure-introducing component having an insertion end portion having substantially the same size as the case opening is incorporated in the storage case. Any structure may be used as long as the potting resin is cast. For example, even if the present invention is applied to the same member, residual gas in the potting resin can be prevented.

Further, in consideration of application of high pressure from the pressure introducing passage 41, a metal or resin sleeve is formed in the groove 45 so as to prevent the O-ring 5 from floating toward the sensor unit.
It may be assembled together with the ring.

Further, the taper shape is also the umbrella-like taper 42, but the point is that the gas can be satisfactorily guided to the gas vent hole 43 along the end face of the insertion end portion 40 of the pressure introducing component 4, for example, fishing. Other cone shapes such as a box shape and a pyramid shape may be used.

[Brief description of drawings]

FIG. 1 is a structural diagram of a pressure sensor device to which an embodiment of the present invention is applied.

FIG. 2 is a diagram illustrating a gas venting effect of one embodiment.

FIG. 3 is an exploded view of one embodiment.

FIG. 4 is a diagram illustrating potting resin injection according to an embodiment.

FIG. 5 is a perspective view of a pressure introducing component according to an embodiment.

FIG. 6 is a structural diagram of a pressure sensor device showing a prior art example.

[Explanation of symbols]

 1 Case 2 Pressure sensor unit 21 Pressure introduction port 3 Wiring board 4 Pressure introduction parts 40 Insertion end 41 Pressure introduction path 42 Umbrella taper 43 Gas vent hole 44 Gas guide groove 5 O-ring 6 Potting resin

Claims (3)

[Scope of utility model registration request] 1. A case having an opening on one side, a pressure sensor unit housed in the case, and a pressure introducing unit which is inserted from the case opening and is airtightly connected to a pressure introducing port extending from the pressure sensor unit. A pressure introducing component having a passage and an insertion side end portion having substantially the same size as the opening of the case, and a potting resin cast in the case, and the insertion side of the pressure introducing component. A through hole is provided in the end portion in the vicinity of the outer peripheral portion thereof, and the end surface of the insertion side end portion extends from the through hole toward the connecting portion of the pressure introducing passage with the pressure introducing port in the case. 2. A pressure detecting device, wherein a cone-shaped taper portion is arranged so as to project toward the pressure sensor unit. 2. A connector portion is set on the case,
A wiring board for electrically connecting an output terminal of the pressure sensor unit and a connector pin of the connector section is arranged in a space between the pressure sensor unit and the pressure introducing component. 1. The pressure detection device according to 1. 3. A groove is formed in the cone-shaped taper portion arranged at the insertion side end of the pressure introducing component in the through hole direction from the top of the cone. The pressure detecting device according to claim 1 or 2.