JP2001004425A - Film type gas meter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve assembling work by making it possible to assemble a counter, a pressure sensor, an isolation valve and a control case, from the same direction in the front. SOLUTION: This gas meter consists of a lower case 1, an upper case 5 and a control case 15. On the front side of the lower case 1, the control case 15 is arranged. A counter 8 constituted of a digit wheel, a pressure sensor 9 and an isolation valve 16 are arranged in the front part of the upper case 5. Lead wires 18 of the pressure sensor 9 and the isolation valve 16 are electrically connected with a controller 14 arranged in the control case 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a membrane gas meter, and more particularly to a membrane gas meter provided with a controller using a microcomputer.

[0002]

2. Description of the Related Art Conventionally, in a film-type gas meter using a microcomputer which operates a shut-off valve by a controller when an abnormal gas pressure is detected by a pressure sensor, as shown in FIG. A circuit board (controller) in which an upper case 103 is disposed on an upper part and electronic parts such as a microcomputer are mounted on a front part of the lower case 102.
A control case 105 for covering the case 104 is arranged, and a counter 106 is arranged at the front of the upper case 103 and a counter cover 107 is arranged for covering the same. The valve 108 and the pressure sensor 109 are arranged side by side and a cover 111 covering them is arranged, and the lead wire 110 of the shut-off valve 108 and the pressure sensor 109 is routed from the rear of the gas meter to the front of the gas meter through the outside of the gas meter. Some are connected to the controller 104.

[0003]

As described above, when the controller 104 and the counter 106 are disposed at the front and the shut-off valve 108 and the pressure sensor 109 are disposed at the rear, these assembling operations are performed in the lower part. It must be performed from both the front side and the rear side of the case 102 and the upper case 103, and the assembling work is not efficient, and the lead wire 110 connecting the controller 104 with the shut-off valve 108 and the pressure sensor 109 becomes longer. Reliability such as noise resistance decreases,
Further, there is a problem that it takes time and effort to route the lead wire 110, and the lead wire 110 becomes long, so that the unit cost of the lead wire 110 increases.

Further, since the lead wire 110 is routed outside the lower case 102, the lead wire 110 is seen from the outside, and there is a problem that the lead wire is easily tampered with such as cutting.

Further, in the case where the shut-off valve 108 and the pressure sensor 109 are arranged side by side as described above, the pressure introduction hole for the pressure sensor 109 is formed as an oblique hole, or another component for introducing the pressure is required. There is a problem.

Accordingly, an object of the present invention is to provide a film-type gas meter that solves the above problems.

[0007]

According to a first aspect of the present invention, there is provided a film-type gas meter comprising a lower case, an upper case, and a control case. A case is arranged, a counter consisting of a numeral wheel, a pressure sensor, and a shutoff valve are arranged at the front of the upper case, and the lead wires of the pressure sensor and the shutoff valve are electrically connected to a controller arranged in the control case. It is characterized by the fact that the connection is made.

According to a second aspect of the present invention, in the first aspect, the pressure sensor and the shut-off valve are arranged in a vertical positional relationship. According to a third aspect of the present invention, in the first or second aspect, mounting holes are formed at substantially four corners of a back plate portion of the control case, and the control case is formed by mounting screws through the mounting holes. Are mounted on the upper case and the lower case, and one of the mounting holes has substantially the same diameter as the mounting screw diameter, and the other mounting hole is larger than the diameter of the mounting screw. .

According to a fourth aspect of the present invention, in the third aspect, the mounting screw is a stepped screw, the step of which is engaged with the lower case or the upper case, and the mounting screw is screwed. A seat plate made of an elastic material is interposed between the head and the back plate of the control case.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described based on an embodiment shown in FIGS. As shown in FIG. 2, the sac membranes 2 and 3 are built in the lower case 1, and when the sac membranes 2 and 3 in which gas flows move back and forth, the movement is transmitted to the upper case 5 by the transmission mechanism 4. The rotation is transmitted to the rotation shaft 6 provided in the rotation direction.

At the front of the upper case 5 fixedly mounted on the upper part of the lower case 1, a counter 8 composed of a numeral wheel 7 is assembled. The amount of gas used is displayed.

Further, as shown in FIG. 1, a pressure sensor 9 for detecting an abnormal gas pressure is provided at a front portion of the upper case 5 as shown in FIG. Shut-off valve 10 that shuts off a gas flow path by a signal
Are arranged, and the pressure sensor 9 and the shutoff valve 1 are arranged.
The shut-off valve 10 is disposed below the pressure sensor 9 in the illustrated embodiment. The pressure sensor 9 and the shutoff valve 10 are assembled to the upper case 5.

The counter 8, the pressure sensor 9 and the shut-off valve 10 are covered with a cover 11, which is fixed to the upper case 5 by screws or the like. Also, the cover 11
Is provided with a window 12 at the front of the counter 8 and a transparent plate 13 so that the display value of the counter 8 can be seen from outside. Further, the chamber 5a containing the counter 8 and the chamber 5b containing the pressure sensor 9 and the shut-off valve 10 are partitioned by a partition wall W, and the chamber 5a is sealed with the outside air, and the chamber 5b is in communication with the atmosphere. It is in a state.

A control case 15 containing a controller (circuit board) 14 on which electronic parts such as a microcomputer are mounted is disposed at the front of the lower case 1. The back case 15a of the control case 15 is assembled and fixed to the front side surfaces of the upper case 5 and the lower case 1 with mounting screws or the like. Further, the control case 15 is disposed with a gap 16 between its back surface and the front surface of the lower case 1. A substantially lower half of the front surface of the control case 15 is formed with a lid 15b, and the lid 15b is
7 detachably provided on the control case 15 side.

The pressure sensor 9 and the shut-off valve 10 arranged at the front of the upper case 5 and the controller 14 are electrically connected to each other by a lead 18 made of a multi-core wire. The lead wire 18 is wired so as to pass through a gap 16 on the back side of the control case 15, and one end (upper end side) of the lead wire 18 passes through the lower case of the upper case 5 or the cover 11 and the pressure sensor 9 and the shutoff valve 10. The other end (lower end side) is inserted into the control case 15 from the back side of the control case 15 through an insertion hole 19 formed in the lower end of the back plate 15 a of the control case 15, The unit is electrically connected to the controller 14.

In the front part of the upper case 5, that is, in the cover 11, a transmitting magnet 20 rotationally driven by the rotation of the rotary shaft 6 is disposed downward. A reed switch 21 is disposed in the control case 15 so as to face the transmitting magnet 20. The reed switch 21 detects the rotation state of the transmitting magnet 20, and the gas flow state is detected by the controller 14. I am to judge.

Next, a mounting structure for mounting the control case 15 to the upper case and the lower case 1 will be described. The control case 15 is formed of a resin, and the back plate 15a is formed with mounting holes 22 to 25 at substantially four corners thereof as shown in FIG. The mounting screws 26 to 29 are inserted into the mounting holes 22 to 25, and the upper mounting holes 22 and 23 are screwed into the front surface of the metal upper case 5 by the mounting screws 26 and 27 and assembled. The mounting holes 24 and 25 are screwed to the front surface of the metal lower case 1 by mounting screws 28 and 29 and assembled to assemble the control case 15 into the upper case 5 and the lower case 1.

One of the mounting holes 22 to 25, in the illustrated embodiment, the upper mounting hole 22 is formed as a reference hole through which a mounting screw 26 is inserted, and the other three mounting holes 23 to 25 are formed. Reference numeral 25 denotes a hole having a diameter larger than the diameter of the mounting screws 27 to 29. In the example of FIG. 3, the mounting hole 23 is formed as an elliptical hole, and the mounting holes 24 and 25 are mounted on the mounting screws 28 and 2.
It is formed in a circular hole having a diameter larger than 9.

Normally, the metal of the upper case 5 and the lower case 1 and the resin of the control case 15 have a difference in linear expansion coefficient depending on the ambient temperature. Therefore, as described above, one of the mounting holes 22 is used as a reference hole, and the other mounting holes 23 to 25 are made larger in diameter than the mounting screws 27 to 29. The control case 15 is positioned with respect to the reference hole 22 and the expansion and contraction of the control case 15 around the reference hole 22 when the ambient temperature changes (in the directions of arrows A, B, and C in FIG. 3).
The absorption was carried out at 3 to 25 so that no stress was applied to the control case 15.

As described above, the control case 15 is positioned with respect to the upper case 5 by using the upper mounting hole 22 attached to the upper case 5 having the transmitting magnet 20 therein as a reference hole, so that the transmitting magnet 20 can be positioned. The mounting position accuracy of the reed switch 21 with respect to the position is increased. Normally, if the mounting error of the reed switch 21 with respect to the transmitting magnet 20 is large, the problem that the on / off ratio variation of the reed switch 21 becomes large occurs. However, by providing the reference hole 22 as described above, this problem is solved. .

As described above, the other mounting holes 23-2
5 absorbs the expansion and contraction of the control case 15 so that the control case 15
To prevent cracking.

Further, as a structure for mounting the control case 15 to the upper case 5 and the lower case 1, as shown in FIG. 4, the mounting screw 26 is a stepped screw and the step 26b is engaged with the upper case 5. A seat plate 30 made of an elastic material such as a rubber seat is interposed between the screw head 26a of the mounting screw 26 and the control case 15. The other mounting screws 27 to 29 also use stepped screws and interpose the seat plate 30 in the same manner. By using the stepped screw and interposing the seat plate 30 in this manner, when the control case 15 is mounted, the stepped portion 26b of the mounting screw 26 prevents the mounting screw from being overtightened, and the tightening force of the mounting screw 26 is reduced. Does not act directly on the control case 15 made of resin.
Cracks can be prevented. The control case 15 can be similarly prevented from cracking at the other mounting screws 27 to 29.

[0023]

As described above, in the present invention, the counter, the pressure sensor, the shut-off valve, and the controller, which are composed of a numeral wheel, are arranged at the front of the upper and lower cases, so that they can be assembled from the same direction. Assembly work is improved.

Further, the lead wire connecting the pressure sensor and the shut-off valve to the controller is shorter than that which is drawn from the rear part of the meter to the front part as shown in FIG. 3 and reliability such as noise resistance is reduced. In addition to the improvement, the unit cost of the lead wire is reduced.

Further, since the pressure sensor, the shut-off valve, and the controller are all disposed at the front of the meter, the lead wire can be raised through the back side of the control case and can be wired into the upper case. Therefore, the lead wire can be arranged on the back side of the control case without routing the outside of the meter as in the related art, so that the lead wire can not be seen from the outside, and mischief such as cutting of the lead wire can be prevented. .

Further, by arranging the pressure sensor and the shut-off valve in an up-and-down positional relationship as described in claim 2, the problem of the conventional side-by-side arrangement can be solved.
Furthermore, by forming one of the mounting holes to have substantially the same diameter as the mounting screw, the accuracy of the mounting position of the control case can be increased, and the other mounting holes can be made larger than the mounting screw diameter. By making the control case larger, it is possible to prevent the control case from cracking due to thermal deformation when the control case is made of resin.

Further, by using a stepped screw and interposing a seat plate made of an elastic material, the control case can be prevented from cracking due to excessive tightening of the mounting screw.

[Brief description of the drawings]

FIG. 1 is a front view of a membrane gas meter according to an embodiment of the present invention, in which a cover for covering a front side of an upper case is removed.

FIG. 2 is a sectional view taken along line XX in FIG. 1 with a front cover of an upper case assembled.

FIG. 3 is a view showing a mounting hole of the control case shown in FIGS. 1 and 2;

FIG. 4 is a sectional view showing a mounting structure of a mounting hole in FIG. 3;

FIG. 5 is a longitudinal sectional view showing a conventional membrane gas meter.

[Explanation of symbols]

 1 lower case 5 upper case 8 counter 9 pressure sensor 10 shut-off valve 14 controller 15 control case 18 lead wire 22-25 mounting hole 26-29 mounting screw 26b step

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiaki Yamada 2-70, Millennial, Atsuta-ku, Nagoya-shi, Aichi F-term (reference) in Aichi Watch Electric Co., Ltd. 2F030 CA01 CB01 CC13 CE13 CE14 CE23 CE25 CF05 CF11 CF20 CH03

Claims (4)

[Claims] 1. A membrane gas meter comprising a lower case, an upper case, and a control case, wherein a control case is arranged in front of the lower case, and a counter consisting of a numeral wheel, a pressure sensor, and a shutoff valve are provided in front of the upper case. Wherein the pressure sensor and the lead wire of the shut-off valve are electrically connected to a controller arranged in the control case. 2. The gas meter according to claim 1, wherein the pressure sensor and the shut-off valve are arranged in a vertical positional relationship. 3. A control hole is formed at substantially four corners of a back plate portion of the control case, and the control case is mounted to the upper case and the lower case by a mounting screw through the mounting hole. The membrane gas meter according to claim 1, wherein one of the mounting holes has substantially the same diameter as the mounting screw, and the other mounting hole has a diameter larger than the diameter of the mounting screw. 4. A seat plate made of an elastic material between the screw head of the mounting screw and the back plate of the control case, wherein the mounting screw is a stepped screw and the step is engaged with the lower case or the upper case. The gas meter according to claim 3, wherein the gas meter is interposed.