JP2010091488A - Diaphragm type gas meter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a diaphragm type gas meter having a structure not requiring the production of valves having different adjustable angles even in the case of altering the adjustable angles of valves to valve seats by an instrumental error adjusting device. <P>SOLUTION: In the diaphragm type gas meter provided with a crank mechanism, the crank mechanism includes: a phase shaft member 31 connected to a large toggle via a small toggle and mounted to a rotary valve to be a shaft indicating the rotation phase of the rotary valve according to reciprocating movements of the large toggle; a crankshaft member 33 fixed to the phase shaft member 31 to be a crankshaft; and a rotating disk center shaft member 34 fixed to the crankshaft member 33 and fixed to the center of a magnetic rotating disk. The phase shaft member 31 is provided in such a way as to be attached to and detached from the crank mechanism. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a membrane gas meter.

  For example, as disclosed in Patent Documents 1 and 2, the membrane gas meter has four measuring chambers formed by two measuring membranes and a partition wall in the main body case, and the fluid to be measured flows into the measuring chamber. By doing so, the measuring membrane reciprocates, and the gas on both sides of the measuring membrane is alternately discharged out of the main body case. The reciprocating motion of the metering membrane is converted into a rotational motion, and a rotary valve (hereinafter simply referred to as a valve) is driven to distribute the gas, and the flow rate is calculated by detecting the rotation of the valve. In the membrane gas meter, it is also possible to display the integrated flow rate by driving the counter by this rotational movement.

  The configuration of such a membrane gas meter will be described with reference to FIGS. FIG. 8 is a partially broken front view showing a conventional membrane gas meter, and FIG. 9 is a side sectional view of the same. 10 is a perspective view showing the appearance of the metering unit of the membrane gas meter of FIGS. 8 and 9, FIG. 11 is a top view of the metering unit of FIG. 10, and FIG. 12 is the phase axis and crank in the metering unit of FIG. It is a figure for demonstrating the positional relationship with an axis | shaft.

  As shown in FIG. 8, the conventional membrane gas meter has a main body case (lower case) constituting the lower part and an upper case constituting the upper part, and the upper case is provided with a gas inlet 8a and a gas outlet 8b. It is done. The lower space provided in the main body case and the upper space provided in 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 by a partition wall. It has been. Each of the front weighing chamber 1a and the rear weighing chamber 1b is provided with a weighing membrane 10, and each weighing chamber 1a, 1b is separated (separated) by the weighing membrane 10 to form a weighing chamber. Yes. That is, as shown in FIG. 9, the first measuring chamber (a) and the second measuring chamber (A) are formed in the front measuring chamber 1a by the measuring film 10, and the first measuring chamber (b) is formed in the rear measuring chamber 1b by the measuring film 10. Three measuring chambers (c) and a fourth measuring chamber (d) are formed.

  In addition, a circular valve seat (valve seat) having an opening is formed in the upper part of each of the measuring chambers (A) to (D). The opening is composed of a circular central opening and a fan-shaped opening having a periphery divided into four. A valve shaft protrudes in the direction perpendicular to the valve seat at the center of the valve seat, and a cylindrical valve 4 is rotatably supported on the upper portion of the valve shaft. As a result, the sealing surface of the valve 4 rotates while slidingly contacting the valve seat, and the opening formed in the valve seat is divided into an opening portion (opening portion viewed from the valve seat side) provided in the main body of the valve 4. The gas flows in and out between the fluid introduction path and the fluid outlet path included in the measuring chambers (a) to (d) by sequentially opening and closing with the other closed part (the closed part viewed from the valve seat side). The flow path is switched to control supply / exhaust of gas into the measuring chambers (A) to (D).

  The structure in which the valve 4 is driven by the reciprocating motion of the measurement membrane 10 caused by the fluid to be measured flowing into the measurement chamber will be described. First, the measurement membrane 10 is supported from both sides by the membrane plate 9. That is, the membrane plate 9 is fixed to both surfaces of the metering membrane 10, thereby moving back and forth together with the metering membrane 10 according to the gas flow rate. The membrane gas meter includes a blade plate 3, a blade shaft member 2, and a link mechanism 6, and transmits the movement displacement of the membrane plate 9 in the horizontal direction.

  The wing plate 3 is fixed to the central portion of the single-sided membrane plate 9 and displaces the membrane plate 9 back and forth in the horizontal direction with respect to the valve shaft by the fluid from the fluid introduction path. That is, the blade plate 3 is a plate that swings according to the back-and-forth movement of the membrane plate 9. The membrane plate 9 and the blade plate 3 are attached via a hinge 11. The blade shaft member 2 is a member that is fixed to each blade plate 3 and serves as a blade shaft that transmits the longitudinal displacement of the membrane plate 9 in the rotational direction. That is, the blade shaft member 2 is a member serving as a blade shaft that converts the swing of each blade plate 3 into a rotational motion. The link mechanism 6 has two large elbows 21 and two small elbows 22. The large elbow 21 is an arm that is fixed to each blade shaft member 2 and reciprocates within a predetermined angle range according to the rotational motion of the blade shaft member 2. Each small elbow 22 is an arm connected to each large elbow 21 so as to be rotatable with respect to each large elbow 21.

  Further, the membrane gas meter includes a magnet turntable 7 provided at an upper portion in the upper case, and a crank mechanism for rotating the magnet turntable 7. The crank mechanism includes a phase shaft member 23a, a crank shaft member 23b, and a rotating disk center shaft member 23c. The phase shaft member 23 a is a member that is connected to the large elbow 21 via the small elbow 22 and is connected to the valve 4 and serves as an axis that indicates the rotational phase of the valve 4 according to the reciprocating motion of the large elbow 21. . Here, one of the small elbows 22 and the other of the small elbows 22 are connected by a phase shaft member 23 a centering on the phase shaft 23 d, and this phase shaft member 23 a is connected to a predetermined position of the valve 4. The membrane plate 9 rotates together with the valve 4 around the valve axis due to the horizontal displacement of the film plate 9. The crankshaft member 23b is a member that is fixed to the phase shaft member 23a and serves as a crankshaft, and is formed integrally with the phase shaft member 23a. The turntable center shaft member 23 c is a member fixed to the crankshaft member 23 b and fixed to the center 7 a of the magnet turntable 7. In this manner, the crankshaft member 23b is fixed to the rotating disk center shaft member 23c provided separately on the valve shaft.

  The magnet turntable 7 is a turntable provided on the top of the rotation shaft of the valve 4 and having a magnet disposed thereon. Magnetic detecting means such as an MR sensor or a reed switch is provided at a position facing the magnet rotating disk 7, and by this magnetic detecting means, the rotation of the magnet rotating disk 7 is changed by a magnetic field of the magnet (magnet ON / OFF). And the flow rate is calculated. Further, the above-described integration display by the gas flow rate counter can be realized by providing a transmission mechanism to the integration counter gear on a part of the rotary shaft of the valve 4 or the rotating disk central shaft member 23c.

  Here, the operation principle of the membrane gas meter will be described. The gas flowing in from the gas inlet 8a passes through the valve 4 and the distribution chamber 5, and is supplied to the designated flow path by the valve 4 among the flow paths partitioned by the valve seat. As a result, the gas in the front and rear weighing chambers 1a and 1b It flows into any of the first to fourth measuring chambers (a) to (d). Here, suppose that gas flows into the first measurement chamber (a) of the front measurement chamber 1a. At this time, the measurement film 10 in the front measurement chamber 1a moves due to the pressure of the gas flowing in, and the gas in the second measurement chamber (a) opposed by the measurement film 10 is discharged. The discharged gas passes through the gas outlet 8b from the distribution chamber 5 and the valve 4 and is discharged out of the gas meter. Further, the movement of the measuring film 10 in the first measuring chamber 1a is converted into the swinging motion of the blade plate 3, converted into the rotational motion of the blade shaft member 2, transmitted to the link mechanism 6, and the valve 4 is moved by the crank mechanism. Drive to rotate. When the valve 4 rotates by a predetermined angle, the flow path between the valve 4 and the distribution chamber 5 is switched, and the gas flowing into the membrane gas meter is led to the fourth measuring chamber (d) of the rear measuring chamber 1b, and the third measuring chamber The gas in (c) is guided to the gas outlet 8b and discharged.

By such a series of operations, the measurement chambers through which the gas enters and exits are switched in the order of (a) → (e) → (b) → (c), and the measurement films 10 provided in the respective measurement chambers 1a and 1b reciprocate. Exercise continues and gas is metered. In the membrane gas meter, the two membranes 10 reciprocate due to the flow of gas into and out of each measuring chamber, but the membranes 10 are moved at different timings. It is the valve 4 that determines the above. The flow path partitioned by the valve seat is selected by the rotation of the valve 4.
JP 2005-201865 A JP 2005-283234 A

  On the other hand, the membrane gas meter tends to increase the measurement volume in the large flow rate region, and has a drop from the instrumental difference in the measurement volume in the small flow rate region. In order to correct this drop, a device difference matching device is used. More specifically, the adjustment angle of the valve 4 with respect to the valve seat is changed by shifting the position where the phase shaft member 23a of the crank mechanism is fixed to the valve 4 by using the instrument difference matching device. Here, the adjustment angle refers to an initial value (initial angle) of the rotational phase of the valve 4 with respect to the valve seat, and based on this value, the fan-shaped opening provided in the valve seat and the opening portion provided in the valve 4 body ( The initial area of the opening region formed from the opening portion as viewed from the valve seat side is changed. By changing the adjustment angle in this way, it is possible to restrict the intake to the measuring chamber, and as a result, it is possible to suppress an increase in the measuring volume in the large flow rate region, reduce the drop, and stabilize the instrumental error over a wide range. .

  However, in the conventional membrane gas meter, since the phase shaft member 23a is integrally formed with the crankshaft member 23b as described with reference to FIG. 12, it is necessary to change the adjustment angle by the instrumental matching device. Therefore, it is necessary to manufacture as many valves as the above-mentioned adjustment angles are changed.

  There are currently seven types of valves in use, and the areas of the recesses into which the phase shaft member 23a is inserted are different. Therefore, when the adjustment angle needs to be changed by the instrument difference matching device, it is necessary to prepare resin molding dies for valves with different adjustment angles for each type, which greatly increases the cost of manufacturing the dies. There is such a problem.

  The present invention has been made in view of the above circumstances, and the object thereof is to produce valves with different adjustment angles even when the adjustment angle of the valve with respect to the valve seat is changed by the instrumental matching device. An object of the present invention is to provide a membrane gas meter having a structure without the above.

  In order to solve the above-described problems, a membrane gas meter of the present invention includes an upper case, a lower case having a partition, a membrane for separating a region partitioned by the partition and forming a gas measurement chamber, A membrane plate fixed to the membrane and movable back and forth according to the gas flow rate, a vane plate fixed to the membrane plate and swinging according to the back-and-forth motion of the membrane plate, and swinging the blade plate into a rotational motion A blade shaft member to be converted into a blade shaft, a large elbow that is fixed to the blade shaft member and reciprocates within a predetermined angle according to the rotational motion of the blade shaft member, and a small arm connected to the large elbow An elbow, a rotary valve for switching a flow path for gas to flow between flow paths of each measuring chamber formed by the partition wall and the film, and a magnet turntable provided at an upper portion in the upper case Rotate the magnet turntable around the same axis as the rotation axis of the rotary valve. In the membrane gas meter provided with a crank mechanism, the crank mechanism is connected to the large elbow via the small elbow and is attached to the rotary valve, and the rotary according to the reciprocating motion of the large elbow. A phase shaft member serving as an axis indicating the rotational phase of the valve, a crank shaft member serving as a crank shaft fixed to the phase shaft member, and a rotating disk fixed to the crank shaft member and fixed to the center of the magnet rotating disk A center shaft member, wherein the phase shaft member is detachable from the crank mechanism.

  According to another aspect of the present invention, there is provided a membrane gas meter according to the above-described membrane gas meter, wherein the phase shaft member is in contact with the rotary valve at a position where the phase shaft member is in contact with the rotary valve. It is characterized by being shifted in the axial direction.

  Furthermore, the membrane gas meter according to another embodiment of the present invention is the membrane gas meter according to any one of the above-described membrane gas meters, wherein the phase shaft member has a portion that contacts when the rotary shaft is attached to the rotary valve. It is formed by shifting in the circumferential direction of rotation.

  The membrane gas meter according to the present invention eliminates the need for manufacturing valves having different adjustment angles even when the adjustment angle of the valve with respect to the valve seat is changed by the instrument difference matching device.

  Hereinafter, the membrane gas meter according to the present invention will be described with reference to the drawings, but the configuration described in the background art can be applied except for the connection portion between the crank mechanism and the crank mechanism on the rotary valve side. That is, the membrane gas meter according to the present invention has a membrane (a measuring chamber formed by a partition wall) for separating an upper case, a lower case having a partition wall, and a region partitioned by the partition wall to form a gas measuring chamber. A metering membrane for further separation, a membrane plate fixed to the membrane and movable back and forth according to the gas flow rate, a wing plate fixed to the membrane plate and oscillating according to the longitudinal movement of the membrane plate, A blade shaft member that is a blade shaft that converts motion into rotational motion, a large armrest that is fixed to the blade shaft member and reciprocates within a predetermined angle according to the rotational motion of the blade shaft member, and is connected to the large armrest A valve (rotary valve) that switches the flow path of gas in and out of the flow path of each measuring chamber formed by a partition and a membrane, and a magnet rotation provided in the upper part of the upper case The magnet rotating disk is rotated around the same axis as the rotation axis of the disk and the valve. And a crank mechanism that. The crank mechanism is connected to the large elbow via a small elbow, and is attached to the valve and is a phase shaft member serving as an axis indicating the rotational phase of the valve according to the reciprocating motion of the large elbow. A crankshaft member that is fixed to the member and serves as a crankshaft, and a rotating disk center shaft member that is fixed to the crankshaft member and fixed to the center of the magnet rotating disk.

  FIG. 1 is a diagram illustrating a configuration example of a crank mechanism in a membrane gas meter according to an embodiment of the present invention. FIG. 1A is a perspective view of a crank mechanism, FIG. 1B is a top view of a crankshaft member, and FIG. 1C is a partial cross-sectional view showing an attachment structure between the crankshaft member and a phase shaft member. .

  A crank mechanism 30 illustrated in FIG. 1 has a crank shape by a phase shaft member 31, a crank shaft member 33, and a rotating disk center shaft member 34. A rotating disk center shaft member 34 is vertically attached to one end side of the crankshaft member 33.

  A phase shaft insertion hole 33 a is provided on the other end side of the crankshaft member 33. That is, in the present invention, the phase shaft member 31 that is a part of the crank mechanism 30 is provided so as to be detachable from the crank mechanism 30.

  As shown in FIG. 1C, in order to hold the phase shaft member 31 so as not to easily come off from the crankshaft member 33, the phase shaft insertion hole 33a forms a fastening portion having a small diameter at a part 33b, The shaft member 31 is formed so as to have a shape in which a portion 31a on the distal end side is recessed. Then, the crankshaft member 33 and the phase shaft member 31 are fixed by using this fastening method (snap fit) using the elasticity of the phase shaft member 31.

  The phase shaft member 31 is provided with a small elbow positioning part 32, and the two small elbows are connected between the small elbow positioning part 32 and the crankshaft member 33. Thereby, the motion of the two films is transmitted as a circular motion of the phase shaft member 31 through the blade plate, the blade shaft, the large elbow, and the small elbow. Here, as shown in FIGS. 1A and 1B, the rotating disk center axis 34c (valve axis) and the phase axis 31c are parallel to each other, and therefore the distance (R) from the valve axis to the phase axis 31c is set. It becomes a radius and repeats circular motion around the valve axis.

  As a result of this circular motion, the crankshaft member 33 and the rotating disk center shaft member 34 rotate around the rotating disk center axis 34c (that is, around the valve shaft), and the magnet rotating disk provided on the valve shaft rotates. To do. At this time, the valve also rotates around the same center due to the circular motion.

  In this way, by adopting a structure in which the phase shaft member 31 can be removed, only the phase shaft member 31 is replaced with one having a different shape without changing the shape of the valve (no need to manufacture valves having different adjustment angles). Thus, it becomes possible to correct the drop by changing the adjustment angle of the valve with respect to the valve seat by the instrument difference matching device, and to change the measurement volume. Note that how the shape of the phase shaft member 31 is varied will be exemplified in the following other embodiments.

  FIG. 2 is a diagram showing a configuration example of a crank mechanism in a membrane gas meter according to another embodiment of the present invention. 2A is a perspective view of the crank mechanism, FIG. 2B is a top view of the crankshaft member, and FIG. 2C shows a mounting structure of the crankshaft member and the phase shaft member and the shape of the phase shaft member. FIG.

  The crank mechanism 30 illustrated in FIG. 2 is different from the crank mechanism 30 illustrated in FIG. 1 only in the shape of the phase shaft member 31, and only the difference will be described. As shown in FIG. 2A, the crank mechanism 30 in FIG. 2 cuts out a part of the phase shaft member 31 below the small elbow metal positioning portion 32 (in this example, cuts out so as to leave a D shape). The phase shaft 31c is substantially shifted rearward (the direction opposite to the rotation direction of the phase shaft member 31). Thus, by forming the concave portion on the valve side so that the valve contact portion 31b of the phase shaft member 31 contacts, the valve contact surface becomes L1 as shown in FIGS. 2 (B) and 2 (C). Just move backwards. Of course, by providing the contact portion 31b in the D shape on the opposite side, it is possible to move in the rotational direction of the phase shaft member 31 and the valve.

  In this way, the phase shaft member 31 is formed by shifting the portion 31b that contacts when attached to the valve in the rotational direction (corresponding to the rotational direction of the valve 4 at the time of attachment) from the other portions or in the opposite direction. Is preferred. However, a concave portion on the valve side is formed so that the valve contact portion 31b of the phase shaft member 31 contacts. Then, several phase shaft members 31 that change the valve contact portion 31b (that is, L1 changes) are manufactured so as to be attached to the concave portion (the concave portion of one valve). By selecting, the phase shaft member 31 with which the valve abuts can be varied with respect to the rotation direction of the valve. That is, the portion 31b of the phase shaft member 31 that contacts the valve is shifted in the circumferential direction of the valve (rotating direction or the opposite direction), and the phase shaft member 31 (that is, L1 is changed so that the shifting distance is changed). By manufacturing the phase shaft member 31), it is possible to perform the same drop correction instrument difference matching as when the valve adjustment angle is changed.

  FIG. 3 is a diagram showing another configuration example of a crank mechanism in a membrane gas meter according to another embodiment of the present invention, and is a diagram showing a configuration example different from FIG. 3A is a perspective view of the crank mechanism, and FIG. 3B is a top view of the crankshaft member.

  The crank mechanism 30 illustrated in FIG. 3 is different from the crank mechanism 30 illustrated in FIG. 2 only in the shape of the phase shaft member 31, and only the difference will be described. As shown in FIG. 3A, the crank mechanism 30 shown in FIG. 3 has a notch formed as a cylinder 31d. Like the example shown in FIG. 2, the position of contact with the valve is rearward by L1 (reverse to the valve rotation direction). Direction).

  That is, since the portion of the phase shaft member 31 that contacts the valve (the left side of the cylinder 31d in the drawing) is shifted in the circumferential direction of the valve (rotation direction or the opposite direction), the same drop is obtained when the adjustment angle of the valve is changed. Compensate instrumental error matching.

  Further, in the crank mechanism 30 of FIG. 3, the portion of the phase shaft member 31 that contacts the valve (the upper and lower sides of the column 31d, that is, the center axis side of the rotating disk and the opposite side) is shifted in the valve radius R direction (valve shaft side). As a result, the same effect as changing the crank radius can be obtained, and the measuring volume can be changed. This principle will be described later in an example with reference to FIGS. In this way, the phase shaft member 31 shifts the portion 31b that comes into contact with the valve in the direction of the rotation center axis of the magnet rotating disk 7 (corresponds to the direction of the rotation center axis of the valve 4 when installed) from the other portions. It is preferable to be formed.

  FIG. 4 is a diagram illustrating another configuration example of the crank mechanism in the membrane gas meter according to another embodiment of the present invention, and is a diagram illustrating a configuration example different from FIGS. 2 and 3. 4A is a perspective view of the crank mechanism, FIG. 4B is a top view of the crankshaft member, and FIG. 4C shows an attachment structure between the crankshaft member and the phase shaft member and the shape of the phase shaft member. FIG.

  The crank mechanism 30 illustrated in FIG. 4 has a shape in which the cylinder 31d of the phase shaft member 31 is shifted like the cylinder 31e in the crank mechanism 30 illustrated in FIG. 3, and only the difference will be described. The crank mechanism 30 shown in FIG. 4 is formed by bending a lower elbow metal positioning portion into an L shape as shown in FIG. 4 (A) to form a cylinder 31e. FIGS. 4 (B) and 4 (C) As shown, the position in contact with the valve can be shifted rearward (reverse to the rotational direction) by L2 as in the example of FIG. Then, the distance L2 can be shifted larger than the example (L1) of FIG. 3, and even when the valve angle adjustment is large, it can be dealt with.

  That is, since the portion of the phase shaft member 31 that contacts the valve (the left side of the cylinder 31e in the drawing) is shifted in the circumferential direction of the valve (rotation direction or the opposite direction), the same drop is obtained when the adjustment angle of the valve is changed. Compensate instrumental error matching.

  Further, in the crank mechanism 30 shown in FIG. 4, as in the crank mechanism 30 shown in FIG. 3, the portion of the phase shaft member 31 that contacts the valve (the upper and lower sides of the column 31e, that is, the center axis side of the rotating disk and the opposite side) Since the structure is shifted in the radius R direction, the same effect as changing the crank radius can be obtained, and the measuring volume can be changed.

  FIG. 5 is a top view showing another example of the crankshaft member and the phase shaft member in the crank mechanism in the membrane gas meter according to the present invention. The phase shaft member 31 shown in FIG. 5 is obtained by cutting a part of the side surface into a concave shape and deforming the phase shaft insertion hole 33a of the crankshaft member 33 into a convex shape. As a result, the crankshaft member 33 and the phase shaft member 31 can be positioned with the concavo-convex portion as the origin. Further, it is possible to prevent the phase shaft member 31 from rotating when the valve rotates. Such a configuration can be applied to any of the crank mechanisms 30 illustrated in FIGS. 1 to 4 and the crank mechanism illustrated in FIG.

  FIG. 6 is a diagram showing another configuration example of a crank mechanism in a membrane gas meter according to another embodiment of the present invention, and is a diagram showing a configuration example different from FIGS. FIG. FIG. 7 is a view for explaining the rotation of the valve accompanying the movement of the large elbow and the small elbow when the crank mechanism of FIG. 6 is employed.

  The crank mechanism illustrated in FIG. 6 is the crank mechanism 30 illustrated in FIG. 3 in which the column 31d of the phase shaft member 31 is shifted like a column 31g, and only the difference will be described. The crank mechanism of FIG. 6 is formed by shifting a cylinder 31g toward the center of the rotating disk with respect to the phase axis 31c. Since the portion of the phase shaft member 31 that contacts the valve (the upper side of the cylinder 31g in the drawing, that is, the center axis side of the rotating disk) is shifted by the distance r in the radius R direction of the valve, the valve shaft and the phase shaft 31c have a radius R. Instead, it moves circularly with a radius Rr, and the same effect as changing the crank radius shorter by r can be obtained, and the measuring volume can be changed.

  This will be described more specifically with reference to FIG. The rotation radius R of the phase shaft member 31 in contact with the valve controls the movement of the blade. As the turning radius R increases, the movable range of the large elbow 21 increases, and the width of the longitudinal motion of the blade connected to the blade shaft also increases. In the case of the radius R, as shown in FIGS. 7A and 7B, the large elbow 21 is movable in the range of θ1 <θ <θ2.

  On the other hand, as illustrated in FIG. 6, the phase shaft member 31 in contact with the valve is moved by r toward the valve shaft side with respect to the phase shaft 31c, and the distance from the phase shaft 31c of the phase shaft member 31 in contact with the valve Is set to R-r, the total length of the large elbow 21 and the small elbow 22 is not changed, so that the minimum angle of the large elbow 21 is limited to a direction in which it increases. When this angle is θ3, θ3> θ1.

  Similarly, since the maximum angle of the large elbow 21 is limited to a direction that becomes smaller than θ2, when this angle is θ4, θ2> θ4. That is, when the rotation radius of the phase shaft member 31 in contact with the valve is reduced by r, the movable range of the large elbow 21 is θ3 <θ <θ4, and the angular range of the large elbow 21 is narrower than that of the radius R. Limited in direction.

  As a result, the movable range in the front-rear direction of the blade plate via the blade shaft is similarly reduced, so that the amount of measurement per time can be reduced and the increase in the measurement volume can be limited.

  6 also has a structure in which the portion of the phase shaft member 31 that contacts the valve (the left side of the cylinder 31g in the drawing) is shifted in the circumferential direction (rotation direction) of the valve. Instrument difference matching with the same head correction as that changed.

It is a figure which shows one structural example of the crank mechanism in the film | membrane type gas meter which concerns on one Embodiment of this invention. It is a figure which shows one structural example of the crank mechanism in the film | membrane type gas meter which concerns on other embodiment of this invention. It is a figure which shows the other structural example of the crank mechanism in the membrane type gas meter which concerns on other embodiment of this invention. It is a figure which shows the other structural example of the crank mechanism in the membrane type gas meter which concerns on other embodiment of this invention. It is a top view which shows the other example of the crankshaft member and phase shaft member in the crank mechanism in the film | membrane type gas meter which concerns on this invention. It is a figure which shows the other structural example of the crank mechanism in the membrane type gas meter which concerns on other embodiment of this invention. It is a figure for demonstrating rotation of the valve | bulb accompanying the movement of a large elbow metal and a small elbow metal when the crank mechanism of FIG. 6 is employ | adopted. It is a partially broken front view which shows the conventional film | membrane type gas meter. It is a sectional side view of the membrane gas meter of FIG. It is a perspective view which shows the external appearance of the measurement part of the film | membrane type gas meter of FIG.8 and FIG.9. It is a top view of the measurement part of FIG. It is a figure for demonstrating the positional relationship of the phase axis and crankshaft in the measurement part of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a ... Front measuring chamber, 1b ... Rear measuring chamber, 2 ... Blade shaft member, 3 ... Blade plate, 4 ... Valve, 5 ... Distribution chamber, 6 ... Link mechanism, 7 ... Magnet rotating disk, 7a ... Magnet rotating disk center 8a ... gas inlet, 8b ... gas outlet, 9 ... membrane plate, 10 ... metering membrane, 11 ... hinge, 21 ... large elbow, 22 ... small elbow, 23a, 31 ... phase shaft member, 23b, 33 ... Crankshaft member, 23c ... Rotary disc center shaft member, 23c, 34 ... Rotary disc center shaft member, 23d, 31c ... Phase shaft, 30 ... Crank mechanism, 31b ... Valve contact portion, 31d, 31e, 31g ... Cylinder, 32 ... small elbow positioning part, 33a ... phase axis insertion hole, 34 ... rotating disk central axis member, 34c ... rotating disk central axis.

Claims (3)

An upper case, a lower case having a partition, a membrane for separating a region partitioned by the partition to form a gas measurement chamber, and a membrane plate fixed to the membrane and movable back and forth according to the gas flow rate A blade plate fixed to the membrane plate and swinging according to the longitudinal movement of the membrane plate, a blade shaft member serving as a blade shaft for converting the swing of the blade plate into a rotational motion, and fixed to the blade shaft member Each measuring chamber formed by a large elbow that reciprocates within a predetermined angle range according to the rotational movement of the blade shaft member, a small elbow that is connected to the large elbow, the partition wall, and the membrane. A rotary valve that switches a flow path of gas between the flow paths, a magnet turntable provided in an upper part of the upper case, and the magnet having the same axis as the rotation center axis of the rotary valve as the rotation center In a membrane gas meter equipped with a crank mechanism for rotating a turntable,
The crank mechanism is connected to the large elbow via the small elbow, and is attached to the rotary valve and serves as an axis indicating the rotational phase of the rotary valve according to the reciprocating motion of the large elbow. A member, a crankshaft member fixed to the phase shaft member and serving as a crankshaft, and a turntable center shaft member fixed to the crankshaft member and fixed to the center of the magnet turntable,
The membrane gas meter, wherein the phase shaft member is detachable from the crank mechanism.   2. The film according to claim 1, wherein the phase shaft member is formed by shifting a portion in contact with the rotary valve in a direction of a rotation center axis of the magnet turntable from another portion. Gas meter.   3. The phase shaft member is formed by shifting a portion that abuts when attached to the rotary valve in a circumferential direction of rotation of the rotary valve from other portions. Membrane gas meter.

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