JP2001201383A - Method of reducing pressure loss in existing diaphragm type gas meter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily reduce a pressure loss without applying major improvement in an existing diaphragm type gas meter. SOLUTION: This invention provides a method for improving the existing gas meter of diaphragm type provided with a gas distributing exhaust unit for introducing gas flowing in from a gas inlet 7a selectively into the first and second measuring chambers 11a, 12a, 11b, 12b, and for discharging selectively the gas inside the first and second measuring chambers to flow out from a gas outlet 7b, so as to reduce a pressure loss. A distributing member 30 of the gas distributing exhaust unit is replaced with one having large opening areas of its flow passages 31a, 32a, 31b, 32b, in the method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for reducing pressure loss in an existing membrane gas meter which is improved from an existing membrane gas meter to reduce pressure loss.

[0002]

BACKGROUND OF THE INVENTION In gas meters for city gas, models (numbers) are provided in accordance with the gas flow rate to be used and the like. The transition to the new issue number is underway.

In such a situation, for example, an existing No. 3 meter is replaced with a No. 4 having a larger flow rate in order to smoothly use the existing No. 3 gas meter while effectively utilizing the existing gas meter. There is a demand for a so-called No. 3 meter to be used as a No. 4 meter. However, if the No. 3 meter is used as it is as the No. 4 meter, the pressure loss increases with an increase in the flow rate, so that it is necessary to reduce the pressure loss.

[0004] The present invention has been made in view of the above-mentioned circumstances, and the pressure in an existing membrane gas meter which can easily reduce the pressure loss without making a significant improvement to the existing membrane gas meter. It is an object to provide a loss reduction method.

[0005]

Means for Solving the Problems The present inventors have made intensive efforts and obtained the following findings. That is, in the existing membrane gas meter, a gas distribution / discharge unit such as a valve and a distribution member (valve seat) is provided for each of the measuring chambers to distribute and discharge gas. Since the gas flow path formed by the distribution / discharge unit has a very complicated shape, it has been found that the gas flow path resistance of the gas flow path having the complicated shape is large. Further, based on that knowledge, the present inventors repeated detailed experiments, and found that the gas distribution and discharge unit of the existing film-type gas meter could be improved without modifying the meter casing such as the main body case and upper case. It has been found that if a part is improved, the gas passage resistance in that part can be suppressed, and the pressure loss of the whole meter can be sufficiently reduced, and the present invention has been accomplished.

That is, the present invention comprises a meter casing partitioned by a partition wall into a lower space and an upper space, wherein the lower space is provided with first and second measuring chambers, and is provided above the meter casing. A gas inlet and a gas outlet are provided, and a gas distribution / exhaust unit attached to the partition wall selectively introduces gas flowing into the upper space from the gas inlet into the first and second measuring chambers. A pressure loss reducing method in an existing membrane gas meter configured to selectively discharge gas in the first and second measuring chambers and to flow out from the gas outlet, wherein a part of the gas distribution and exhaust unit is provided. By replacing at least one of the size and the shape of the gas flow path formed by the gas distribution and exhaust unit, It is summarized as those to reduce anti-a.

In the pressure loss reducing method of the present invention,
The passage resistance of the gas flow path formed by the gas distribution / exhaust unit can be easily reduced simply by replacing a part of the gas distribution / exhaust unit in the gas meter.

In the present invention, as described below, it is preferable to replace the distribution members and valves of the gas distribution and exhaust unit with predetermined ones.

That is, in the present invention, the gas distribution and exhaust unit includes a distribution member, and the distribution member is provided with first and second flow paths communicating with the first and second measuring chambers. Preferably, an exhaust guide passage communicating with the gas outlet is provided, and a configuration is adopted in which the distribution member is replaced with one having a large passage cross-sectional area of the first and second passages.

Further, in the present invention, the gas distribution / exhaust unit includes a distribution member and a valve, and the distribution member is connected to the first and second measuring chambers.
A flow path is provided, and an exhaust guide path communicating with the gas outlet is provided, and the valve is provided at a position in the distribution member that spans the first flow path and the exhaust guide path, and the second flow path and the exhaust A gas return which is provided so as to be displaceable between a position astride the conduit and a gas which flows out of the first channel or the second channel to make a U-turn and guide the gas to the exhaust conduit. It is desirable to adopt a configuration in which a concave portion is provided and the valve is replaced with a valve having a large gas return concave portion.

Further, in the present invention, the gas distribution unit includes a distribution member and a valve, and the distribution member is provided with first and second flow paths communicating with the first and second measuring chambers. An exhaust channel communicating with the gas outlet is provided, and the valve is provided at a position in the distribution member that straddles the first channel and the exhaust channel, and
A gas is provided so as to be displaceable between a flow path and a position extending over the exhaust flow path, and the gas flowing out of the first flow path or the second flow path is U-turned to guide the gas to the exhaust flow path. It is preferable to adopt a configuration in which a concave portion for gas return is provided, and the valve is replaced with a valve in which a back wall surface of the concave portion for gas return is formed in a curved surface corresponding to a U-turn path of gas.

[0012]

FIG. 1 is a front sectional view showing a membrane gas meter to which a pressure loss reducing method according to an embodiment of the present invention can be applied. FIG. 2 is an exploded view of the periphery of a gas distribution and exhaust unit in the membrane gas meter. FIG. 3 is a side sectional view showing the membrane gas meter.

As shown in these figures, a meter casing (10) of the gas meter has a case body (10a) constituting a lower part thereof and an upper case (10b) constituting an upper part thereof. The upper case (10b) is provided with a gas inlet (7a) and a gas outlet (7b). The lower space (1) provided inside the case body (10a) and the upper space (5) provided inside the upper case (10b) are defined by the upper wall of the case body (10a), that is, the partition wall (3). ), And the lower space (1) is divided into a front measurement space (1a) and a rear measurement space (1).
b). Furthermore, each weighing space before and after (1
a) (1b) is a measuring membrane (2a) movable in the front-back direction
(2b), the front metering space (1
a) is provided with first and second measurement chambers (11a) and (12a), and the first measurement chamber is arranged in the rear measurement space (1b).
And second measuring chambers (11b) and (12b).

As shown in FIG. 4, the meter casing (1)
A base (20) for attaching a distribution member (30) described later is provided on one side of the partition wall (3) in the area (0). The pedestal (20) has four communication holes (21a), (22a), and (21) communicating with the four measurement chambers (11a), (12a), (11b), and (12b), respectively.
b) (22b) is formed. Furthermore, the rear first and second communication holes are formed between the front first and second communication holes (21a) and (22a).
An exhaust inlet (25a) is formed in a region extending between the communication holes (21b) and (22b), and the pedestal portion (2) is formed.
0), an exhaust outlet (25b) is formed at an end thereof, and an exhaust guide channel (2) is formed between these entrances (25a) and (25b).
5).

As shown in FIG. 1, the exhaust outlet (25b) communicates with a gas outlet (7b) through an exhaust passage (6) of the meter casing (10).

As shown in FIGS. 2 and 5, the pedestal (2
The distribution member (30) screwed and fixed to (0) is made of a molded article of a hard synthetic resin such as polyacetal, and corresponds to the four communication holes (21a) (22a) (21b) (22b). (31a) (32a) (31b)
(32b) is formed. Further, the distribution member (30) includes:
A front exhaust passage (35a) is formed between the front first and second passages (31a) and (32a),
A rear exhaust passage (35b) is formed between the rear first and second flow passages (31b) and (32b).

As shown in FIGS. 2 and 6, the distribution member (3
0), the front first and second flow paths (31a) (32)
a), a front valve (40a) is provided so as to be displaceable and movable between the first and second flow paths (31b) and (32).
A rear valve (40b) is provided so as to be displaceably movable between b) and (b).

Each of the valves (40a) and (40b) has an exhaust channel (35) of the distribution member (30) at the center on the lower surface side.
a) A concave portion (41) for gas return is provided corresponding to the opening shape of (35b), for example, a front valve (4).
0a), the gas return recess (41) is the front first
In a state where the first flow path (31a) is disposed at a position from the flow path (31a) to the front exhaust guide flow path (35a), the first flow path (31a) passes through the gas return recess (41) of the valve (40a).
Is configured to communicate with the front exhaust passage (35a). That is, when the valves (40a) and (40b) are displaced and moved, the space between the front first flow path (31a) and the front exhaust gas flow path (35a), and the front second flow path (32a) and the front part are reduced. The exhaust passages (35a) alternately communicate with each other, and the first rear passage (31b) and the rear exhaust passage (35a).
b) and the rear second flow path (32b) and the rear exhaust flow path (35b) are configured to alternately communicate with each other.

On both sides of the gas return concave portion (41) on the lower surface side of each of the valves (40a) (40b), closed portions (42) (42) are provided. For example, in a state in which the front valve (40a) has the gas return recess (41) adapted to the front exhaust guide channel (35a), the gas return recess (41) provides the exhaust guide channel (41). 35a) is closed and the closing part (42) is closed.
(42) allows the front first and second flow paths (31a) (3
2a) is configured to be closed. When the rear valve (40b) has the gas return recess (41) fitted to the rear exhaust passage (35b), the exhaust return passage (35b) is formed by the gas return recess (41). While being closed, the closing portions (42) and (42)
The rear first and second flow paths (31b) (32b) are configured to be closed.

On the other hand, the measuring membranes (2a) and (2b) are configured to be movable back and forth, and each of the measuring membranes (2a) and (2b).
And each of the valves (40a) (40b) are connected via a power transmission mechanism (50) including a crank mechanism, and as described below, each measurement membrane (2a) (2b).
Each valve (40a)
(40b) is configured to be displaced and moved.

That is, as shown in FIG. 7 (a), when the front measurement membrane (2a) is disposed at the front end position in the front measurement space (1a), the front valve (40a) causes the front valve (40a) to operate. The first and second flow paths (31a) and (32a) and the front exhaust passage (35a) are closed. At this time, in the rear measuring space (1b), the rear measuring membrane (2)
b) is in the state of moving forward, and the rear valve (4)
0b) is that the gas return recess (41) is the first rear portion.
The rear first flow path (31b) and the rear exhaust flow path (35b) are arranged between the flow path (31b) and the rear exhaust flow path (35b), and the rear second flow path (32).
b) is open.

Therefore, the gas in the rear first metering chamber (11b) is supplied to the rear first channel (31b) and the rear exhaust channel (3).
5b), further through the exhaust channel (25), the exhaust channel (6)
And discharged through a gas outlet (7b) and supplied to a predetermined gas appliance. On the other hand, the gas flowing into the upper space (5) from the gas inlet (7a) flows into the rear second flow path (32).
Through b), it is sucked into the rear second measuring chamber (12b) and weighed.

Next, as shown in FIG. 7B, in the rear measuring space (1b), the forward movement of the rear measuring membrane (2b) is completed, and the gas in the rear first measuring chamber (11b) is removed. When the discharge is completed and the gas suction of the rear second measurement chamber (12b) is completed, the rear first and second flow paths (31b) and (32b) are connected to the rear exhaust passage by the rear valve (40b). The flow path (35b) is closed. At this time, in the front metering space (1a), the front metering membrane (2a) is in the middle of moving backward, and the front valve (40a)
The gas return recess (41) allows communication between the front second flow path (32a) and the front exhaust guide flow path (35a) and opens the front first flow path (31a).

Accordingly, the gas in the front second metering chamber (12a) flows through the front second flow path (32a) and the front exhaust flow path (3).
While being discharged through 5a), the gas in the upper space (5) is sucked into the front first measuring chamber (11) through the front first flow path (31a) and measured.

Next, as shown in FIG. 7C, in the front measurement space (1a), the backward movement of the front measurement film (2a) is completed, and the gas in the front second measurement chamber (12a) is removed. When the discharge is completed and the gas suction of the front first metering chamber (11a) is completed, the front first and second flow paths (31a) and (32a) are connected by the front valve (40a). The front exhaust passage (35a) is closed. At this time, in the rear metering space (1b), the rear metering membrane (2b) is in the middle of moving backward, and the rear valve (40b) is moved by the gas return recess (41) by the rear second flow path. (3
2b) and the rear exhaust passage (35b), and the rear first passage (31b) is opened.

Therefore, the gas in the rear second metering chamber (12b) is supplied to the rear second flow path (32b) and the rear exhaust conduit (3b).
While being discharged through 5b), the gas in the upper space (5) is sucked into the rear first measuring chamber (11b) through the rear first flow path (31b) and measured.

Subsequently, as shown in FIG. 7D, in the rear measuring space (1b), the rearward movement of the rear measuring membrane (2b) is completed, and the gas discharge from the rear second measuring chamber (12b) is completed. When the gas suction of the rear first metering chamber (11b) is completed, the rear first and second flow paths (31b) and (32b) and the rear exhaust flow path (35b) are operated by the rear valve (40b). ) Is closed. At this time, in the front measurement space (1a), the front measurement membrane (2a) is in the middle of moving forward, and the front valve (40a) is moved forward by the gas return recess (41). One channel (31
a) and the front exhaust passage (35a) are communicated, and the front second passage (32a) is opened.

Therefore, the gas in the front first metering chamber (11a) flows through the front first flow path (31a) and the front exhaust flow path (3).
While being discharged through 5a), the gas in the upper space (5) is sucked into the front second measurement chamber (12a) through the front second flow path (32a) and measured.

The above operation is continuously and repeatedly performed.
The gas flow is measured.

On the other hand, in the above-mentioned membrane type gas meter, in order to reduce the pressure loss, it is only necessary to replace at least a part of the gas distribution and exhaust unit such as the distribution member (30) and the valves (40a) (40b).

That is, as the distribution member (30), FIG.
As shown in (a), each flow path (31a) (32a) (3
1b) Replace the opening area (passage cross-sectional area) of (32b) with a larger one. For your reference,
The conventional flow path (31a) having a small opening area as indicated by the imaginary line in FIG.
(32a), (31b) and (32b) are shown.

In accordance with a change in the opening area of the flow paths (31a) (32a) (31b) (32b) in the distribution member (30), a valve (40a) having a shape corresponding thereto is changed.
Replace with (40b). At this time, as shown in FIG. 6B, as the replacement valves (40a) (40b), the depth and width of the gas return concave portion (41) are larger than those of the conventional one, and The inner wall surface (41c) of the return recess (41) formed in an arc shape following the U-turn path of gas is used.

In the valves (40a) and (40b), when the depth of the gas return recess (41) is increased, the height of the valve itself is also increased. However, by making the distribution member (30) thinner accordingly. , Can be easily mounted in a predetermined mounting space.

Further, with the increase of the opening area of the distribution member (30) and the enlargement of the valves (40a) (40b), the displacement (movement width) of the valves (40a) (40b) increases. (40a) The length of the crank shaft (52) and the fulcrum position of the crank shaft (52) in the crank mechanism for controlling the displacement movement of the (40b), and the fulcrum position of the valves (40a) and (40b) are appropriately changed, so that the valve (40
a) (40b) can be sufficiently dealt with, and the valve (40a)
(40b) A smooth displacement operation can be obtained.

A gasket (60) is provided between the upper end surface of the meter body (10a) and the lower end surface of the upper case (10b), as shown by oblique lines in FIG. The gasket (60), which is also arranged at the outer peripheral edge of the exhaust outlet (25b), is replaced with a gasket (60) that does not protrude into the exhaust outlet (25b). As shown by the imaginary line in the figure, the conventional gasket (60)
Usually, one end edge (60a) is arranged so as to protrude into the exhaust outlet (25b).

As described above, according to the pressure loss reducing method of the present embodiment, the distribution member (30) is connected to the flow path (31a).
Since the openings (32a), (31b) and (32b) are replaced with those having a large opening area, the flow paths (31a) (32)
a) The passage resistance of the gas when passing through (31b) and (32b) can be reduced, and the pressure loss can be reduced.

Further, in this embodiment, the valve (40
a) Since (40b) is replaced with a gas return concave portion (41) having a large depth or width, the gas return concave portion (41) has sufficient gas to make a U-turn. A large-sized path can be secured, and the gas can smoothly flow in a U-turn, so that the gas passage resistance can be reduced and the pressure loss can be further reduced.

Further, since the inner wall surface (41c) of the gas return recess (41) in the valves (40a) (40b) is formed in an arc shape following the U-turn path of the gas, the gas is transferred to the inner wall surface (41c). ), The gas flows more smoothly, and at this point, the gas passage resistance can be reduced, and the pressure loss can be further reduced.

Further, since the gasket (60) is replaced with a gasket (60) that does not project into the exhaust outlet (25b), the gas passage resistance when passing through the exhaust outlet (25b) can be reduced, and the pressure loss can be further reduced. Can be reduced.

Further, in this embodiment, the distribution member (30) and the valve (40) can be used without improving the meter body (1) and the meter casing such as the upper case (5).
a) Pressure loss can be easily reduced simply by replacing (40b), a part of the crank mechanism, the gasket (60), and the like.

[0041]

As described above, according to the method for reducing pressure loss in the existing membrane gas meter according to the present invention, the gas distribution / exhaust unit can be easily formed simply by replacing a part of the gas distribution / exhaust unit in the gas meter. Thus, there is an effect that the passage resistance of the gas flow path can be reduced and the pressure loss can be reduced.

In the present invention, when the distribution members and valves of the gas distribution / exhaust unit are replaced to increase the cross-sectional area of the passage or to smoothly form the gas passage, the above effects can be obtained more reliably. There is an advantage that you can.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a gas meter to which a pressure loss reducing method according to an embodiment of the present invention can be applied.

FIG. 2 is an exploded perspective view showing the periphery of a gas distribution and exhaust unit in the gas meter according to the embodiment.

FIG. 3 is a side sectional view showing the gas meter of the embodiment.

4A is a plan view showing a distribution member mounting base in the gas meter according to the embodiment, and FIG. 4B is a cross-sectional view taken along the line IV-IV of FIG.

5A and 5B are views showing a distribution member attached to the gas meter according to the embodiment, wherein FIG. 5A is a plan view and FIG.
Is a bottom view.

6A and 6B are views showing a valve attached to the gas meter according to the embodiment, wherein FIG. 6A is a plan view, FIG. 6B is a sectional view taken along the line VI-VI of FIG. () Is a bottom view.

FIG. 7 is a schematic sectional view showing the gas meter according to the embodiment in accordance with the measuring operation procedure.

FIG. 8 is a plan view showing a distribution member mounting base in the gas meter according to the embodiment with a gasket arranged.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Meter main body 5 ... Upper case 7a ... Gas inlet 7b ... Gas outlet 11a, 11b ... 1st measuring chamber 12a, 12b ... 2nd measuring chamber 30 ... Distributing member 31a, 31b ... 1st flow path 32a, 32b ... 2nd Flow passages 35a, 35b Exhaust flow passage 40 ... Valve 41: Gas return recess 41c ... Back wall surface

 ────────────────────────────────────────────────── ─── Continued on the front page (71) Applicant 000116633 Aichi Watch Electric Co., Ltd. 1-2-70, Chitose, Atsuta-ku, Nagoya-shi, Aichi (72) Inventor Hiroshi Matsushita 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi Inside Osaka Gas Co., Ltd. (72) Megumi Iwakawa 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi Inside Osaka Gas Co., Ltd. (72) Inventor Yama ▲ saki ▼ Yu 10 Kagida-cho, Chudo-ji, Shimogyo-ku, Kyoto Kansai Gasme (72) Inventor Toshifumi Matsuda 10 Kanodaji Kadamachi, Shimogyo-ku, Kyoto-shi Kansai Gasmeter Inc. (72) Inventor Takaaki Yoshida 10 Nakadoji-Kida-cho, Shimogyo-ku, Kyoto Kansai Gasmeter Co., Ltd. (72) Inventor Akio Yoshinaga 4-7-13-Nishiiwata, Higashi-Osaka-shi, Osaka Inside Kansai Research Laboratory, Kinmon Manufacturing Co., Ltd. (72) Inventor Shinji Tomoe Nagoya, Aichi Prefecture 1-70, Millennichi, Atsuta-ku, Aichi, Japan Aichi Watch & Electronics Co., Ltd. (72) Inventor Katsuhisa Hanaki 2-70, Millennium, Atsuta-ku, Nagoya-shi, Aichi F-term (reference) 2F030 CC13 CE40 CH05 3J071 AA02 BB11 CC11 DD01 FF03

Claims (4)

[Claims] 1. A meter casing which is divided into a lower space and an upper space by a partition wall, wherein a first and a second measuring chambers are provided in the lower space, and a gas inlet and a gas are provided above the meter casing. An outlet is provided, and a gas distribution / exhaust unit attached to the partition wall selectively introduces gas flowing into the upper space from the gas inlet into the first and second measuring chambers,
A method for reducing pressure loss in an existing membrane gas meter in which gas in said first and second measuring chambers is selectively discharged and discharged from said gas outlet, wherein a part of said gas distribution and exhaust unit is replaced. By changing at least one of the size and shape of the gas flow path formed by the gas distribution and exhaust unit,
A method for reducing pressure loss in an existing gas meter, wherein the gas passage resistance is reduced. 2. The gas distribution and exhaust unit includes a distribution member, wherein the distribution member is provided with first and second flow paths communicating with the first and second measuring chambers, and is provided at the gas outlet. 2. A pressure loss in an existing membrane gas meter according to claim 1, wherein an exhaust gas passage communicating with the gas meter is provided, and the distribution member is replaced with a gas passage having a large cross-sectional area of the first and second flow passages. Reduction method. 3. The gas distribution / exhaust unit includes a distribution member and a valve, wherein the distribution member is provided with first and second flow paths communicating with the first and second measuring chambers, and includes An exhaust conduit communicating with an outlet is provided, and the valve is between a position of the distribution member that extends over the first flow passage and the exhaust conduit and a position that extends over the second flow passage and the exhaust conduit. While being provided so that it can be displaced, the gas flowing out of the first flow path or the second flow path,
2. The existing membrane gas meter according to claim 1, further comprising a gas return recess for making a U-turn to guide the exhaust gas to the exhaust passage, and replacing the valve with a valve having a large gas return recess. Pressure loss reduction method. 4. The gas distribution unit includes a distribution member and a valve, wherein the distribution member is provided with first and second flow paths communicating with the first and second measuring chambers, and the gas outlet is provided. An exhaust conduit that communicates with the valve is provided. The valve is disposed between a position in the distribution member that straddles the first flow passage and the exhaust conduit, and a position that straddles the second flow passage and the exhaust conduit. Displaceably provided, gas flowing out of the first flow path or the second flow path,
A gas return concave portion is provided for making a U-turn and leading to the exhaust channel, and the valve is formed such that the inner wall surface of the gas return concave portion has a curved surface corresponding to a U-turn path of gas. 2. The method for reducing pressure loss in an existing membrane gas meter according to claim 1, wherein said method is replaced with a new one.