JPH0351726Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a semiconductor pressure transducer used, for example, in a pressure gauge or a differential pressure gauge.

[Prior art]

In recent years, semiconductor sensors of various shapes and types have come to be used as pressure measurement sensors in pressure gauges or differential pressure gauges. One example is a system in which a thin section is formed in a single crystal silicon chip material, and the strain caused by the pressure applied thereto is detected by a Googe bridge that utilizes the viezoresistance effect formed by diffusion of impurities. Such a semiconductor sensor is highly accurate and can be effective in stabilizing quality, which is a great advantage.

By the way, among this type of semiconductor pressure transducer, one is generally known in which a semiconductor sensor is incorporated into a pressure receiving capsule consisting of a casing and a sensor support block that closes the open end of the casing. Pressure capsules are becoming more compact in order to meet the demands for high measurement precision in recent years. Reducing the internal volume as a result of making the pressure capsule more compact is essential in order to prevent changes in the internal pressure within the pressure capsule due to, for example, the influence of ambient temperature.

To this end, there is a need to reduce the outer diameter of the sensor support that is screwed into the pressure-resistant casing in a cartridge manner. However, the sensor support that is screwed into the casing from the open end side is provided with multiple external connection terminals that are connected to the sensor at predetermined intervals in the circumferential direction. It is necessary to form a groove or hole in which the screwing jig for the support base is assembled, avoiding the installation part, and this requires the outer diameter of the support base to be increased to a certain extent, which makes the pressure capsule more compact. This has become a problem in trying to achieve this goal.

[Summary of the idea]

The present invention was developed in view of the above circumstances, and the terminal mounting hole of the sensor support base is formed as a stepped hole having a large diameter hole on the outer end side.
By using this large diameter hole to lock the jig for screwing in the support base, the outer diameter of this sensor support base can be reduced despite its simple configuration. This provides an inexpensive semiconductor pressure transducer that can be made smaller and more compact as a whole, and is also excellent in workability.

〔Example〕

Hereinafter, the present invention will be explained in detail using embodiments shown in the drawings.

1 and 2 show an embodiment of the semiconductor pressure transducer according to the present invention, and in these figures, the semiconductor pressure transducer, which is generally designated by the reference numeral 1, is a diaphragm made of, for example, a silicon single crystal. A pressure receiving capsule consisting of a shaped semiconductor sensor 2, a casing 4 forming an internal pressure chamber 3 for accommodating the semiconductor sensor 2, and a sensor support 5 screwed into the casing 4 from the open end side to close the opening. 6, and a plurality of external connection terminals 7 arranged on the sensor support base 5 at predetermined intervals in the circumferential direction so as to surround the sensor 2 and connected to the sensor 2, each of these terminals 7 being connected to the sensor 2. Support stand 5
It is held through a glass sleeve 9 within a terminal mounting hole 8 that is drilled through the terminal. In addition, in the figure, 10 is a pressure guiding hole that is bored in the casing 4 and introduces fluid pressure into the pressure chamber 3, and 11 is a sensor support stand 5.
The semiconductor sensor 2 is joined onto the support base 5 so as to close the pressure guiding hole 11, which is similarly drilled in the semiconductor sensor 2. Further, the sensor support base 5 is screwed in by screwing a threaded portion 12 formed on the outer periphery of its tip to a threaded portion 13 on the inner wall of the casing 4, and a flange portion 5a provided on the outer end thereof 4 side locking step 4
The casing 4 and the support base 5 are assembled and fixed by being engaged with the casing 4 and the supporting base 5, and the joint opening between the casing 4 and the support base 5 is sealed by welding or the like.

Now, according to the present invention, the terminal mounting hole 8 drilled in the sensor support base 5 described above is formed as a stepped hole having a large diameter hole 20 at its outer end side. Support base screwing jig 21
A feature is that the support base 5 is screwed into the casing 4 by locking the engaging cylinder portion 22 of the support base 5.

In other words, the problem that arises from conventionally forming the locking groove for locking the screwing jig at a position that avoids the terminal mounting hole on the support base, that is, the problem that occurs when the outer diameter of the support base becomes large, is eliminated. Therefore, the above-mentioned terminal mounting holes are skillfully utilized. In this way, the jig 21 can be locked in the large diameter hole 20 of the mounting hole 8 of the support base 5 described above, and the support base 5 can be screwed into the casing 4 easily and securely. As a result, the outer diameter of the support base 5 can be reduced to the necessary minimum, and the pressure receiving capsule 6 can be made smaller and more compact as a whole. Further, the large diameter hole 20 to which the jig 21 described above is locked is the mounting hole 8.
Since concentric machining is sufficient, the number of machining steps is not much of an issue, and it has the advantage of being superior in terms of processability and cost.

Here, as is clear from FIG. 1, the hole 22a in the engagement cylinder part 22 of the screwing jig 21 is for loosely fitting the outer end of the terminal 7 to prevent damage to the terminal 7. The large-diameter holes 20 in the mounting holes 8 on the support stand 5 side, in which the engaging cylinder portion 22 of this jig 21 is locked, do not need to be formed in all the mounting holes 8;
4 locations as shown in the diagram, and in some cases 2 locations
It will be easily understood that it is only necessary to form the mounting hole 8 at the location.

It goes without saying that the present invention is not limited to the structure of the embodiment described above, and that the shape, structure, etc. of each part can be modified and changed as appropriate.

[Effect of idea]

As explained above, according to the semiconductor pressure transducer according to the present invention, the terminal mounting hole of the sensor support base screwed into the casing is formed as a stepped hole having a large diameter hole at the outer end side. Therefore, although the structure is simple, inexpensive, and has excellent workability, the large-diameter portion of the mounting hole is used to lock the screwing jig, and the support base can be easily and securely mounted. The sensor can be screwed into the casing and fixed, thereby reducing the outer diameter of the sensor support and making the entire sensor smaller and more compact, which has great practical effects.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing an embodiment of a semiconductor pressure transducer according to the present invention, and FIG. 2 is an exploded perspective view showing a sensor support base and a screwing jig, which are the main parts thereof. DESCRIPTION OF SYMBOLS 1... Semiconductor pressure transducer, 2... Semiconductor sensor, 3... Internal pressure chamber, 4... Casing, 5...
...Sensor support stand, 6...Pressure receiving capsule, 7...Terminal for external connection, 8...Terminal mounting hole, 10, 11
. . . Pressure guiding hole, 20 . . . Large diameter hole, 21 . . . Screwing jig, 22 .

Claims (1)

[Scope of utility model registration request] It consists of a casing that forms an internal pressure chamber in which a semiconductor sensor is arranged, and a sensor support that is screwed into the inside of the casing to close the open end. A plurality of external connection terminals connected to the sensor are arranged through the sensor, and at least two of the terminal mounting holes for holding these terminals are formed as large diameter holes on the outer end side. Semiconductor pressure transducer.