JP2010025570A - Diaphragm type gas meter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To ensure the high dimension accuracy by providing a constitution assembled without use of a dedicated jig and stably applying a solder when a blade and a blade shaft are fixed in a diaphragm type gas meter. <P>SOLUTION: The blade shaft 2 is inserted into an inner space of a curved engagement wall 31 when the blade 3 and the blade shaft 2 are assembled, and simultaneously abuts on first and second regulating walls 32, 33. The first and second regulating walls 32, 33 are constituted so as to dispose the blade shaft 2 in a predetermined position of the blade 3 when the blade shaft 2 abuts on the first and second regulating walls 32, 33. A distance L between the center of a shaft passage hole 34 and the center of the blade shaft 2 can be accurately configured. An inside radius R of the engagement wall 31 is configured so as to be larger than a radius of the blade shaft 2. A fixed gap is obtained between the engagement wall 31 and the blade shaft 2. The solder can stably run into the gap. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a membrane gas meter, and more particularly to a membrane gas meter having a mechanism for converting a reciprocating motion of a membrane in a measuring chamber into a swinging motion of a blade.

  A membrane gas meter is generally used as a gas meter for small and medium flow rates for city gas. The membrane gas meter is designed to discharge gas from both sides of the measuring membrane alternately to the outside of the main body case by the reciprocating motion of the measuring membrane built in the two measuring chambers inside the main body case. It is converted into a rotational motion using a mechanism, and has a structure in which a slip valve is driven to distribute gas and a counter is driven to display an integrated flow rate.

FIG. 8 is a partially broken front view showing a membrane gas meter, and FIG. 9 is a side sectional view of the same.
The casing of the membrane gas meter has a main body case constituting the lower part and an upper case constituting the upper part, and a gas inlet 12 and a gas outlet 13 are provided in the upper case. The lower space provided inside the main body case and the upper space provided inside the upper case are partitioned by a partition wall, and the lower space is partitioned into a front weighing chamber 1a and a rear weighing chamber 1b. ing. First and second weighing chambers (a) and (b) are formed in the front weighing chamber 1a by the weighing membrane 7a, and the third and fourth weighing chambers (c) are formed in the rear weighing chamber 1b by the weighing membrane 7b. (D) is formed. The reciprocating motion of the measuring membranes 7a and 7b is transmitted to the blade 3 through the hinge frame 5 attached to the membrane plates 8 and 8 attached to both surfaces of the measuring membrane, and the swing of the blade 3 is further controlled by the blade shaft 2 And is transmitted to the link mechanism 6 to drive the valve 4 and drive the flow rate integrating mechanism.

FIG. 10 is a diagram for explaining the operating principle of the membrane gas meter.
The gas flowing in from the gas inlet 12 passes through the valve 4 and the distribution chamber 14, and any of the first to fourth measuring chambers (a), (b), (c) and (d) of the front and rear measuring chambers 1a and 1b. It flows into the crab. Here, as shown in FIG. 10 (A), suppose that gas flows into the first measuring chamber (a) of the front measuring chamber 1a, and the measuring membrane 7a moves due to the pressure of the flowing gas at this time. The gas in the opposing second measuring chamber (A) partitioned by the membrane 7a is discharged. The discharged gas passes through the gas outlet 13 from the distribution chamber 14 and the valve 4 and is discharged out of the gas meter. Further, the movement of the measuring film 7a is converted into a swinging motion of the blade 3 and transmitted to the link mechanism 6 through the blade shaft 2, driving the flow rate integrating mechanism of the gas meter, and driving the valve 4 to rotate.

  When the valve 4 rotates by a predetermined angle, the flow path between the valve 4 and the distribution chamber 14 is switched, and as shown in FIG. 10B, the gas flowing into the gas meter is transferred to the fourth measuring chamber (E) in the rear measuring chamber 1b. The gas in the third measuring chamber (c) is led to the gas outlet 13 and discharged. Through the above series of operations, as shown in FIGS. 10 (A) to 10 (D), the measuring chamber through which the gas enters and exits is switched in the order of (a) → (e) → (b) → (c), The metering films 7a and 7b continue to reciprocate, and gas is metered. In order to convert the reciprocating motion of the measuring membranes 7 a and 7 b into the rotational motion of the blade shaft 2, the measuring membranes 7 a and 7 b are supported by the blade 3 by the membrane support structure using the hinge frame 5. A blade shaft 2 is fixed to the blade 3.

As a structure for supporting a wing, a measuring film bearing retaining structure described in Patent Document 1 is known. In this measuring membrane bearing retaining structure, in the bearing retaining structure in which the bearing is engaged with the shaft at the tip of the blade plate and the bearing is screwed to the center portion of the membrane plate sandwiching the measuring membrane from the front and rear, By providing anti-rotation means for restricting the rotation of the bearing around the center of the bearing and at least one of the membrane plates, it is possible to prevent loosening of the screw tightening that causes a measurement error.
JP-A-2005-227209

FIG. 11 is a diagram for explaining a configuration example when assembling a blade and a blade shaft provided in a conventional membrane gas meter, and FIG. 11 (A) shows a state before the blade and blade shaft are assembled. FIG. 11B is a view showing a state in which the wing and the wing shaft are assembled.
The wing 3 is provided with a shaft-through hole 34 to be connected to the hinge frame 5 on one end side thereof. At the connecting portion between the blade 3 and the measuring membranes 7 a and 7 b, the measuring membranes 7 a and 7 b of the membrane gas meter are supported by the membrane plate 8, and the hinge frame 5 is attached to the membrane plate 8. A shaft through hole 34 provided in the blade 3 is formed, the hinge frame 5 is arranged between the shaft through holes 34, and the blade 3 and the hinge frame 5 are connected using a hinge shaft (not shown).

  An engagement wall 31 for fixing the blade shaft 2 is provided on the opposite side of the blade 3. The engagement wall 31 has a curved shape that surrounds the blade shaft 2. And the blade axis | shaft 2 is fixed inside the curved shape.

  FIG. 12 is a side view showing a state when the blade and the blade shaft are assembled. The membrane gas meter is provided at the tip of the blade 3 constituting the link mechanism 6 in order to measure the gas by driving the flow rate integrating mechanism via the link mechanism 6 by using the reciprocating motion of the measurement films 7a and 7b. It is necessary to accurately assemble the dimension between the membrane connecting portion and the blade shaft 2. Specifically, as shown in FIG. 12, the distance L between the center of the shaft hole 34 and the center of the blade shaft 2 needs to be assembled with high accuracy.

  In the conventional configuration, when the blade 3 and the blade shaft 2 are assembled, the distance L is regulated by using a dedicated jig. In this case, an engagement wall 31 having a curved shape surrounding the blade shaft 2 is brought into close contact with the blade shaft using a jig, and solder 35 is poured into the gap between the engagement wall 31 and the blade shaft 2 and fixed. It was.

In the configuration for fixing the conventional blade 3 and the blade shaft 2 as described above, a jig for regulating the positional relationship between the blade 3 and the blade shaft 2 is required. In order to perform management, a highly accurate jig is required, and the jig dimension management is complicated.
Further, in the conventional configuration, since the engagement wall 31 and the blade shaft 2 are brought into close contact with each other, the gap between the engagement wall 31 and the blade shaft 2 is not stable, and there is a problem that the solder does not easily flow.

  Patent Document 1 discloses a connection structure between a blade and a membrane plate, and does not refer to the above-described problem related to the connection between a blade and a blade shaft.

  The present invention has been made in view of the above circumstances, and can be assembled without using a dedicated jig when soldering the blades and blade shafts of a membrane gas meter, and solder can be stably applied. An object of the present invention is to provide a membrane gas meter that can ensure the dimensional accuracy with high accuracy by providing a configuration that can be used.

  The invention of claim 1 has a measuring chamber partitioned by a measuring film that reciprocates back and forth, a rotatable blade shaft inserted into the measuring chamber, and a blade having one end fixed to the blade shaft. In the membrane-type gas meter, the measurement membrane is connected to the other end of the blade, and the blade swings back and forth around the blade axis according to the reciprocating motion of the measurement membrane in the measurement chamber. Is provided with a regulating wall for regulating the fixed position of the blade shaft, and a portion where the blade and the blade shaft are engaged is fixed by solder.

  According to a second aspect of the present invention, in the first aspect of the present invention, the blade has an engagement wall for engaging the blade shaft, and at least a part between the engagement wall and the blade shaft. Is characterized by having a gap through which melted solder can flow.

According to the present invention, when the blade of the membrane gas meter and the blade shaft are fixed, it is possible to assemble without using a dedicated jig and to have a structure capable of stably applying solder, thereby accurately measuring the dimensions. It is possible to provide a membrane gas meter that can ensure accuracy.
In particular, the assembly of the blade and the blade shaft does not require a positioning jig, management of the jig is not required, and the positional relationship between the blade and the blade shaft can be regulated with high accuracy. Moreover, since the gap into which the solder flows can be obtained with certainty, stable soldering is possible.

FIG. 1 is a diagram showing an embodiment of a membrane gas meter according to the present invention, and is a diagram illustrating a configuration example when assembling a blade and a blade shaft of a membrane gas meter. Here, FIG. 1A is a view showing a state before the blade and blade shaft are assembled, and FIG. 2B is a view showing a state where the blade and blade shaft are assembled.
The wing 3 is provided with a shaft-through hole 34 to be connected to the hinge frame 5 on one end side thereof. As described in the background art above, at the connecting portion between the blade 3 and the metering membranes 7a and 7b, the metering membranes 7a and 7b of the membrane gas meter are supported by the membrane plate 8, and a hinge frame is attached to the membrane plate 8. 5 is attached. A shaft through hole 34 provided in the blade 3 is formed, the hinge frame 5 is arranged between the shaft through holes 34, and the blade 3 and the hinge frame 5 are connected using a hinge shaft (not shown).

In the embodiment according to the present invention, an engagement wall 31 for fixing the blade shaft 2, a first restriction wall 32, and a second restriction wall 33 are provided on the opposite side of the blade 3.
The first restriction wall 32 has a shape in which the blade shaft 2 mounted on the engagement wall 31 is sandwiched between the engagement wall 31 and the axial direction of the blade shaft 2 at two positions outside the second restriction wall 33. Is provided. The third restriction wall 33 is configured as a wall portion that protrudes to the inside of the curved engagement wall 31. The protruding portion is formed in a shape that matches the outer peripheral shape of the blade shaft 2.

FIG. 2 is a side view showing a state when the blade and the blade shaft are assembled.
As described above, when the blade 3 and the blade shaft 2 are assembled, it is necessary to set the dimensional accuracy with high accuracy. Specifically, as shown in FIG. 1, it is necessary to assemble the distance L between the center of the shaft hole 34 and the center of the blade shaft 2 with high accuracy.
In the present embodiment, when the blade 3 and the blade shaft 2 are assembled, the blade shaft 2 is inserted into the inner space of the engaging wall 31 that is curved. Then, the blade shaft 2 is pressed against the first restriction wall 32 and the second restriction wall 33 simultaneously. The first restriction wall 32 and the second restriction wall 33 are configured such that when the blade shaft 2 is pressed against the blade shaft 2, the blade shaft 2 is arranged at a predetermined position of the blade 3. The distance L between the center of the hole 34 and the center of the blade axis 2 can be set accurately.

  Further, the R radius inside the engagement wall 31 is set larger than the radius of the blade shaft 2. Therefore, when the blade shaft 2 is pressed against the first restricting wall 32 and the second restricting wall 33, a stable and constant gap is always obtained between the engaging wall 31 and the blade shaft 2. Thereby, solder can be poured stably into the gap between the engagement wall 31 and the blade shaft 2.

FIG. 3 is a view showing another configuration example of the blades of the membrane gas meter according to the present invention. In the configuration example of FIG. 3, in the configuration in which the engagement wall 31, the first restriction wall 32, and the second restriction wall 33 are provided on the wing 3, the concave shape portion 36 is given to the second restriction wall 33. .
The concave portions 36 are provided at two positions on both end portions in the axial direction of the blade shaft 2 with respect to the second restriction wall 33. When the blade shaft 2 is inserted inside the engagement wall 31, the concave portion 36 of the second restriction wall 33 contacts the outer periphery of the blade shaft 2. As a result, a certain gap is formed between the region other than the concave portion 36 of the second restriction wall 33 and the blade shaft 2. Thereby, the solder can flow into the gap, and stable fixing can be performed.

  FIG. 4 is a view showing still another configuration example of the blade of the membrane gas meter according to the present invention. In the configuration example of FIG. 4, in the configuration in which the engagement wall 31, the first restriction wall 32, and the second restriction wall 33 are provided on the wing 3, two concave portions 36 are provided on the second restriction wall 33. To do. Unlike the example of FIG. 3, the concave shaped portion 36 is extended in the bending direction of the first regulating wall 33 (the circumferential direction of the blade shaft 2), and the concave shaped portion 36 is formed over the entire circumference of the first regulating wall 33 in the curved direction. To be.

  When the blade shaft 2 is inserted inside the engagement wall 31, the concave portion 36 of the second restriction wall 33 contacts the outer periphery of the blade shaft 2. As a result, a certain gap is formed between the blade shaft 2 and the region other than the concave portion 36 of the second restriction wall 33 and the engagement wall 31. Thereby, solder can flow into the gap, and stable fixation can be performed.

FIG. 5 is a view showing still another configuration example of the blade of the membrane gas meter according to the present invention. In the configuration example of FIG. 5, in the configuration in which the engagement wall 31, the first restriction wall 32, and the second restriction wall 33 are provided on the wing 3, the shape of the engagement wall 31 is curved as in the above embodiments. The shape is not a shape but a U-shape (a U-shape as viewed from the side).
In other words, the shape of the engagement wall 31 is not limited to the curved shape having R, and may be a U-shape as in this example, so that a gap is secured between the engagement wall 31 and the blade shaft 2. , Solder can flow into the gap.

FIG. 6 is a diagram for explaining a configuration example of the blade axis of the membrane gas meter according to the present invention.
In this example, in the configuration in which the blade 3 is provided with the engagement wall 31, the first restriction wall 32, and the second restriction wall 33, the blade shaft 2 is provided with the recess 21, whereby the blade shaft 2 and the blade 3. A gap is provided between the engaging wall 31 and the engaging wall 31.
That is, as shown in FIG. 6, at least a region in the axial direction of the blade shaft 2 that faces the inner wall surface of the engagement wall 31 when the blade shaft 2 is inserted inside the curved portion of the engagement wall 31 of the blade 3. A recess 21 is provided in a part. The concave portion 21 has a shape in which a part of the outer peripheral surface of the blade shaft 2 is recessed closer to the blade shaft center side than the other portions, and constitutes a shaft portion having a smaller diameter than the periphery. In addition, the portion of the blade shaft that contacts at least a part of the first restriction wall 32 and the second restriction wall 33 does not have the concave portion 21, and the portion of the maximum diameter of the blade shaft is formed by the restriction walls 32 and 33. Get regulated.

With such a configuration, a gap is ensured between the engagement wall 31 and the blade shaft 2, and solder can flow into the gap.
In the configuration in which the recess 21 is provided in the blade shaft 2 as in the present embodiment, the configuration on the blade 3 side may be the configuration shown in FIGS. 1 and 2, or any of FIGS. Such a configuration may be used. Furthermore, a configuration as shown in FIG.

  FIG. 7 is a view showing still another configuration example of the blade of the membrane gas meter according to the present invention. In the configuration example of FIG. 7, in the configuration in which the blade 3 is provided with the engagement wall 31, the first restriction wall 32, and the second restriction wall 33, the blade shaft 2 is formed by the first restriction wall 32 and the engagement wall 31. A hole portion 37 is formed to allow insertion of the. When the blade shaft 2 and the blade 3 are assembled, the blade shaft 2 is inserted into the hole 37 formed by the first restriction wall 32 and the engagement wall 31, and the engagement wall 31 and the blade shaft 2 are assembled. Solder is poured into the gap formed between them and fixed.

It is a figure which shows one Embodiment of the membrane type gas meter by this invention. It is a side view which shows a state when a wing | blade and a blade axis | shaft are assembled. It is a figure which shows the other structural example of the wing | blade of the film | membrane type gas meter by this invention. It is a figure which shows the further another structural example of the wing | blade of the membrane type gas meter by this invention. It is a figure which shows the further another structural example of the wing | blade of the membrane type gas meter by this invention. It is a figure for demonstrating the structural example of the blade axis | shaft of the film | membrane type gas meter by this invention. It is a figure which shows the further another structural example of the wing | blade of the membrane type gas meter by this invention. It is a partially broken front view showing a membrane gas meter. It is a sectional side view showing a membrane type gas meter. It is a figure for demonstrating the principle of operation of a membrane gas meter. It is a figure for demonstrating the structural example at the time of assembling the wing | blade and blade axis | shaft with which the conventional film | membrane type gas meter is equipped. It is a side view which shows a state when a wing | blade and a blade axis | shaft are assembled.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a ... Front measuring chamber, 1b ... Rear measuring chamber, 2 ... Blade shaft, 3 ... Wing, 4 ... Valve, 5 ... Hinge frame, 6 ... Link mechanism, 7a ... Measuring membrane, 7b ... Measuring membrane, 8 ... Membrane plate , 12 ... Gas inlet, 13 ... Gas outlet, 14 ... Distribution chamber, 21 ... Recess, 31 ... Engagement wall, 32 ... Restriction wall, 33 ... Restriction wall, 34 ... Hole, 35 ... Solder, 36 ... Concave shaped part, 37 ... hole.

Claims (2)

A measuring chamber partitioned by a measuring membrane that reciprocates back and forth; a rotatable blade shaft inserted into the measuring chamber; and a blade fixed at one end to the blade shaft; In the membrane gas meter, wherein the metering membrane is connected, and the wing swings back and forth around the wing axis according to the reciprocating motion of the metering membrane in the measuring chamber,
The wing includes a regulating wall for regulating a fixed position of the wing shaft, and a portion where the wing and the wing shaft are engaged is fixed by solder. The membrane gas meter according to claim 1,
The blade has an engagement wall for engaging the blade shaft, and at least a part between the engagement wall and the blade shaft has a gap through which melted solder can flow. A membrane gas meter.

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