JP2002147634A - Cutoff valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a mechanism for fixing a stator to a flange hard to be destructive even if it is used for a long period, and to prevent the leakage of gas in case the mechanism breaks down. SOLUTION: The mechanism for fixing the stator 46 to a mounting plate 57 constitutes a support frame 59. A fitting portion 57c with the support frame 59 is formed outside a seal face 57e of the mounting plate 57. Since the fitting portion 57c is fully disposed on an atmospheric chamber side, the cutoff valve is not susceptible to breaking down. The cutoff valve is highly reliable in air- tightness to prevent the leakage of gas even in the case of the cutoff valve breaks down.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety valve operated by an external situation (International Patent Class F16K 17/36).
The present invention relates to a device using an electric motor as an operating means (International Patent Class F16K 31/04), and more particularly to a shutoff valve used as a shutoff mechanism of a gas shutoff device for preventing a gas accident from occurring. The present invention relates to a shut-off valve using a motor as a power source to perform a shut-off return operation of a flow path by moving a valve body forward or backward with respect to a valve seat formed in the valve seat.

[0002]

2. Description of the Related Art In order to prevent gas accidents, various types of safety devices have been used in the past. Above all, the flow rate of gas is monitored by a built-in gas meter and the flow rate sensor is monitored. Battery power that shuts off gas with the shut-off valve built into the gas meter if it is judged, or if it is judged that there is a dangerous state by monitoring the status of sensors such as earthquake sensors, gas pressure sensors, gas alarms, carbon monoxide sensors, etc. The use of gas meters with built-in gas shut-off devices equipped with microcomputers (hereinafter abbreviated as microcomputer meters) has been promoted due to their advantages such as safety, ease of gas piping, and low price, and in recent years almost all households have been spread. Has been reached. In addition, the ratio of centralized monitoring microcomputer meters with a telemeter function that centrally monitors the gas flow rate information measured by the flow rate sensor using a telephone line etc. has also increased, and the convenience of information terminals has been further improved. It has been demanded. In this centralized monitoring microcomputer meter, the gas can be shut off and returned by simple electric switch operation or remote operation by telephone line etc.
There is a demand for a shut-off valve that does not require energy to maintain the open and closed states, with both gas shut-off and gas return being possible by electric energy from a battery mounted on a microcomputer meter.

Conventionally, as a driving method of the shut-off valve, a method using an electromagnetic solenoid has been mainly used, but in recent years, a relatively strong closing force and a returning force can be realized, and a PM type stepping device capable of holding a state when not energized is used. Attention has been focused on shut-off valves that use a motor as a drive source.Among them, a shut-off valve that has an airtight partition with the rotor inside the gas passage and the stator outside the gas passage is easy to attach to the gas passage. Mainstream.

Hereinafter, a conventional shut-off valve will be described.

A conventional shut-off valve of this type is disclosed in Japanese Unexamined Patent Publication No. 9-21.
No. 0237 and Japanese Unexamined Patent Application Publication No. 11-2352 are generally used. Japanese Patent Application Laid-Open No. 11-2352
As shown in FIG. 5, the shut-off valve described in the publication has a cup-shaped casing 6 with a flange, and a stator 4 is mounted on the outer periphery of the casing 6. The outer bush 3 is fitted, and the stud 5 is integrally formed with the outer bush 3 so as to be eccentric and protrude forward, and the inner bush 12 is inserted into the casing 6, and the outer bush 3 and the inner bush 12 are inserted. The lead screw 17 is rotatably supported in the forward and reverse directions with the male screw portion 17a at the tip protruding forward from the outer bush 3, and the rotor 16 is attached to the lead screw 17 so as to face the stator 4. A thrust load rolling bearing 18 is interposed between the rotor 16 and the outer bush 3 to engage with the stud 5 and It is arranged a valve body 25 screwed to a. The elastic seal member 8, the outer bush 3, and the casing 6 are sandwiched between the stepped flange 2 and the flat plate flange 7, and the stepped flange 2 and the flat plate flange 7 are fixed to each other by the swaged portion 32. An elastic sealing member 33 is provided outside the caulking portion 32 with the stepped flange 2.
And the housing 27 to maintain the airtightness between the stepped flange 2 and the housing 27.

[0006] With respect to the shut-off valve configured as described above,
The operation will be described below.

At the time of abnormal use of gas or the like, the rotor 16 is rotated forward by the energization from a control unit (not shown), the lead screw 17 rotates in the forward direction, and the stud 5 restricts the rotation of the valve body 25. By doing so, the rotary motion is converted into a linear motion, and the valve element 25 is moved from the lead screw 17 side to the valve seat 26.
By advancing to the side and abutting against the valve seat 26, the fluid path is closed and the fluid is shut off. When the valve body 25 is restored, the lead screw 17 is rotated in the reverse direction by an external input, and the stud 5 restricts the rotation of the valve body 25 to convert the rotational motion into a linear motion.
The valve body 25 is retracted from the side to the lead screw 17 side until the short end of the valve body 25 contacts the outer bush 3, and the fluid path is opened to resume the supply of the fluid.

FIG. 6 shows a shut-off valve disclosed in Japanese Patent Application Laid-Open No. 9-210237. This shutoff valve has substantially the same configuration as the shutoff valve in FIG. 5, except that the stator 34 is fixed by spot welding to the flange 35 and the plurality of welds 36. An elastic seal member 33 is sandwiched between the flange 35 and the housing 27 outside the welded portion 36 to keep the flange 35 and the housing 27 airtight.

The operation of the shut-off valve is the same as that of the shut-off valve shown in FIG.

[0010]

This type of shut-off valve is generally attached to a gas meter installed outdoors, and can be used at temperatures from over 50 ° C. in direct sunlight in summer to -20 ° C. in severe winter. Will be exposed to severe temperature changes to temperatures below. Parts on the gas chamber side such as the gas chamber side of the valve body 25 and the flanges 2 and 35 are composed of low molecular hydrocarbon fuel gas or purified impurities such as water, hydrogen sulfide, and sulfur dioxide that are slightly contained in the gas. It will be subjected to the severe temperature changes in an organic environment such as an active gas. In addition, the atmosphere side of the stators 4 and 34 and the flanges 2 and 35 is exposed to severe conditions such as a high-temperature and high-humidity environment close to the saturation humidity outdoors and dew condensation in a gas meter. Among them, high airtight reliability is required to prevent gas leakage during the service period of the gas meter (generally 10 years).

When the stator 4 and the flange 2 are caulked and joined as in the conventional shut-off valve shown in FIG. 5, the caulked deformation portion of the caulked portion 32 has a thin metal surface treatment or peels off. And is easily corroded by moisture. Also, with the caulking residual stress,
The caulked portion 32 is weak on the metal structure, and is likely to generate intergranular corrosion and stress corrosion cracking.

When spot welding is performed between the stator 34 and the flange 35 as in the conventional shut-off valve shown in FIG. 6, the welded portion 36 is locally connected to the welded portion 36 due to local heat generation during welding. Strain remains between the metal structure and the portion, and grain boundary corrosion and stress corrosion cracking are likely to occur. In addition, the surface of the metal around the welded portion 36 is thinned or peeled off, so that it is easily corroded by moisture or the like.

Further, in the above-mentioned conventional shut-off valve, the caulked portion 32 or the welded portion 36 between the stators 4, 34 and the flanges 2, 35 is formed by the elastic seal member 33.
If the caulked portion 32 or the welded portion 36 is damaged due to corrosion, stress corrosion cracking, or the like, there is a possibility that gas leakage will occur from the gas chamber side to the atmosphere side because it is located inside the sealing surface between the housing 5 and the housing 27. There is.

In view of the above-mentioned conventional problems, the present invention does not easily destroy the mechanism for fixing the stator to the flange due to humidity stress, temperature stress, chemical stress, or the like in long-term use, and does not lead to gas leakage even if it is broken. An object of the present invention is to provide a shut-off valve having high airtight reliability.

[0015]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a rotor disposed inside a stator, a partition wall for keeping the rotor and the stator airtight, and a rotor disposed on a rotating shaft of the rotor. The valve mechanism has a seal surface with the fluid chamber on the valve mechanism side, the stator is provided on the back surface, and the rotary shaft is penetrated so that the valve mechanism is located on the back surface. Mounting plate having a portion, a sealing member for holding the mounting plate and the partition wall in an airtight manner, and pressing the stator and the partition wall against the mounting plate in a substantially U-shape, sandwiching both ends into the fitting portions of the mounting plate And the supporting frame thus formed constitutes a shutoff valve.

According to the present invention, the mechanism for fixing the stator to the mounting plate (flange) is a supporting frame, and the fitting portion with the supporting frame is formed outside the sealing surface of the mounting plate. It will be on the room side,
It is not exposed to an organic substance environment such as a fuel gas that is a low molecular hydrocarbon or an active gas that is a refined impurity such as water, hydrogen sulfide, and sulfur dioxide that are slightly contained in the gas. In addition, since the caulked portion is formed in a relatively open place, it does not suck up moisture due to capillary action, etc., and even if it is condensed and dried, it dries relatively quickly, so compared to the conventional shut-off valve The mechanism for fixing the stator to the mounting plate is not easily broken.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A shutoff valve according to the present invention comprises a stator,
A rotor disposed inside the stator, a partition wall for keeping the rotor and the stator airtight, a valve mechanism disposed on the rotation shaft of the rotor, and a seal surface with a fluid chamber on the valve mechanism side; A mounting plate that is penetrated by the rotating shaft so that the valve mechanism is located on the back surface, and has a claw-shaped fitting portion on an outer peripheral portion outside the sealing surface; and a sealing member that hermetically holds the mounting plate and the partition wall. And a support frame in which the stator and the partition are pressed in a substantially U-shape and sandwiched by being pressed against the mounting plate, and both ends are fitted to the fitting portions of the mounting plate.

The mechanism for fixing the stator to the mounting plate (flange) is used as a support frame, and a fitting portion with the support frame is formed outside the sealing surface of the mounting plate. As a result, there is no exposure to an organic substance environment such as a fuel gas which is a low molecular hydrocarbon or an active gas which is a refined impurity such as water, hydrogen sulfide and sulfur dioxide contained in the gas. Also, since the caulked portion is formed in a relatively open place, it does not suck up moisture due to capillary action, etc.
Because it dries relatively quickly even when it is painted with condensation,
The mechanism for fixing the stator to the mounting plate is harder to break than the conventional shut-off valve.

Also, since the fitting portion is completely on the atmosphere side,
Even if the fitting portion is damaged due to corrosion or the like, there is no effect on the inside of the sealing surface of the mounting plate, and no gas leaks from the gas chamber side to the atmosphere side.

As described above, the mechanism for fixing the stator to the mounting plate is unlikely to be broken due to humidity stress, temperature stress, chemical stress, or the like during long-term use, and even if broken, high airtight reliability does not result in gas leakage. Can be provided.

Further, the shut-off valve according to the present invention, in addition to the above features, has an engaging portion for preventing rotation of the stator formed on the support frame.

For this reason, even if a rotation stopper is not formed between the stator and the mounting plate, rotation between the stator and the mounting plate can be prevented, and irregularities or welding that may cause corrosion problems on the inside of the sealing surface of the mounting plate can be prevented. Since it is not required, the mechanism that fixes the stator to the mounting plate due to humidity stress, temperature stress, chemical stress, etc. during long-term use is difficult to break, and even if it breaks, it has high airtight reliability that does not lead to gas leakage. A shut-off valve can be provided.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIGS. 1, 2 and 3 show an open state of a shut-off valve and a shut-off operation of an embodiment 1 of the present invention, respectively.
FIG. 4 is a perspective view showing the shapes of the mounting plate, the stator, and the support frame of the shut-off valve according to the first embodiment of the present invention.

In FIG. 1 and FIG. 4, an exciting coil 4 in which a conductive wire 42 is wound around a coil bobbin 41 having a substantially thread wound shape.
3, a first electromagnetic yoke 44 having a cylindrical portion on the outer periphery and having comb-shaped magnetic poles on the inner periphery, and a substantially disk arranged so as to sandwich the exciting coil 43 between the first and second electromagnetic yokes 44 And two sets of second electromagnetic yokes 45 each having a comb-shaped magnetic pole on the inner periphery and arranged in contact with the disk portions of the second electromagnetic yokes 45 to form a stator 46. . The coil bobbin 41 is desirably made of synthetic resin and has heat resistance and good electrical insulation such as polybutylene terephthalate (PBT). The first electromagnetic yoke 44 and the second electromagnetic yoke 45 are made of a steel plate such as a low-carbon steel plate, an electromagnetic soft iron plate or a silicon steel plate, and are provided with a rust-preventive treatment such as zinc plating, aluminum plating, or a chromic acid treatment film on the surface. Has been applied,
Alternatively, a pre-plated steel sheet such as a galvanized steel sheet is desirable because it is made of an electromagnetic stainless steel sheet and is economically desirable. The comb-shaped magnetic poles of the first electromagnetic yoke 44 and the second electromagnetic yoke 45 mesh with a predetermined gap, and the two sets of comb teeth are substantially the same as the other set of comb teeth in the rotation direction. It is arranged to be located in the gap.

Coaxially inside the stator 46, a two-stage bottom 4
7a, 47b, large and small cylindrical portions 47c, 47d, and a large-diameter cylindrical portion 47c are provided at the open ends with a metallic partition wall 47 having no fitting hole formed by drawing in a pan shape having a flange 47e. Rigid bodies such as non-magnetic stainless steel plates, copper alloys, aluminum alloys, synthetic resins, and ceramics can be selected for the material of the partition wall 47. However, for reasons such as corrosion resistance, strength, creep resistance, and thin-wall workability, austenite is used. The best one is drawn from a stainless steel sheet, and it is desirable that the solid solution is subjected to a solution heat treatment after the drawing to remove residual internal stress and refinement of crystal grains.

A first bearing 48 made of synthetic resin and having a center hole 48a is inserted into the inside of the side surface of the small-diameter cylindrical portion 47d of the partition wall 47. The cylindrical portion 47d of the partition wall 47 and the first
Are fitted with an interference fit. First bearing 4
A thinned ripple-like stress relief portion 48c is formed between the fitting portion 48b of FIG. 8 and the center hole 48a. Also,
A stopper 48d is formed so as to contact the bottom 47a of the partition wall 47. The material of the first bearing 48 is selected from self-lubricating synthetic resins such as polyacetal (POM), polyamide (PA), polytetrafluoroethylene (PTFE) powder, and various synthetic resins containing graphite particles. Although possible, polyacetal is the best for low coefficient of friction and economical reasons. Since this polyacetal has relatively large stress creep and is soft, it is necessary to set a relatively large interference when setting an interference fit. For example, the inner diameter of the cylindrical portion 47d of the partition wall 47 is 8 mm. In the case, the insertion portion 48b of the first bearing 48
Is suitably about 8.05 to 8.1 mm.

A second bearing 49a, a cylindrical portion 49b having an open end 49g perpendicular to the central axis on the side surface, and a flange portion on the outer periphery are provided on the open end side of the pan side surface of the large-diameter cylindrical portion 47c of the partition wall 47. And a synthetic resin lid 49 coaxially with 49c.
The flange portion 49c is fitted and inserted in contact with the flange 47e of the partition wall 47. The cylindrical portion 47c of the partition wall 47 and the fitting insertion portion 49e of the lid 49 are fitted by tight fit. Between the insertion portion 49e of the lid 49 and the second bearing 49a, a thinned ripple-like stress relief portion 49d is formed. This lid 4
As the material of No. 9, polyacetal is most suitable as in the case of the first bearing 48. The interference fit between the cylindrical portion 47c of the partition wall 47 and the insertion portion 49e of the lid 49 may be relatively loose because there is another fixing means to be described later, and also to prevent the disk portion 49f from waving. For example, when the inner diameter of the cylindrical portion 47c of the partition wall 47 is 18 mm, the fitting portion 4 of the lid 49 is used.
The outer diameter of 9e is suitably about 18.02 to 18.08. On the inner surface of the cylindrical portion 49b of the lid 49, convex ribs 50 parallel to the central axis are formed at two places 180 ° apart on the circumference.

Inside the partition 47, a cylindrical permanent magnet 51 polarized in the circumferential direction is provided with a feed screw 5 at one end.
2, the rotating shaft 53, the permanent magnet 51 and the rotating shaft 53
5 comprising a sleeve 54 coaxially holding
5 is the second end of the lid 49 on the end of the rotary shaft 53 on the feed screw 52 side.
Of the first bearing 48 with the opposite end
8a is rotatably loosely inserted and disposed.

Mounting plate 5 mountable in fluid chamber 56
7 is a large-diameter cylindrical portion 4 of a center hole 57a and a partition wall 47 in the center.
Cylindrical step 5 having an inner diameter slightly larger than the outer diameter of 7c
7b, and two claw-shaped fitting portions 5 at the outer peripheral portion.
7c is formed. The end of the large-diameter cylindrical portion 47c of the partition wall 47 is inserted into the step portion 57b, and the cylindrical portion 49b of the lid 49 penetrates the center hole 57a and protrudes toward the fluid chamber 56. An elastic sealing member 58 such as an O-ring made of synthetic rubber is arranged between the inner periphery of the partition 57b and the inner periphery thereof so as to be compressed in the circumferential direction with respect to the central axis of the partition wall 47. The flange portion 49c of the lid 49 is held between the bottom surface 57d of the step portion 57b of the mounting plate 57 and the flange 47e of the partition wall 47.

A seal member 69 is compressed and held between the sealing surface 57e of the mounting plate 57 and the fluid chamber 56, and keeps the space between the mounting plate 57 and the fluid chamber 56 airtight.

A stator 46 is disposed in contact with a flat surface of the mounting plate 57 on the partition 47 side, and the stator 46 and the partition 47 are pressed to be sandwiched between the mounting plate 57 and both ends of the mounting plate 57 are fitted. A generally U-shaped support frame 59 is provided so as to be fitted to the joint 57c. The support frame 59 is formed with an engaging portion 59b that can be engaged with the stator 46 to prevent the stator 46 from rotating. In this example, the engaging portion 59b has a convex shape when viewed from the rear surface, and the distal end portion is inserted into a hole opened in the electromagnetic yoke 44 to engage therewith, and the electromagnetic yoke 44 is attached to the mounting plate 57 at the convex step portion. Biased to the side. Between the stator 46 and the seal member 58, a seal member 58 is provided.
A backup ring 60 is provided to prevent the backup ring 60 from falling off from the stepped portion 57b. The material of the mounting plate 57 and the supporting frame 59 is a rigid material having gas resistance, corrosion resistance, and strength such as a surface-treated steel plate, a stainless steel plate, a copper alloy plate, and an aluminum alloy plate. Treated steel sheet is easy to choose.

The moving body 61 disposed in the fluid chamber 56 has a center hole 61a screwed into the feed screw 52 of the rotating shaft 53, and a substantially disk-shaped spring receiver 61b is formed on the stator 46 side.
At the other end, a large-diameter engagement ring portion 61c is formed, and a small-diameter cylindrical portion 61d is formed therebetween. On the outer periphery of the spring receiver 61b, concave portions 61e that can be engaged with the ribs 50 of the lid 49 are formed at four locations at 90 ° intervals on the circumference. The engagement of the concave portion 61e with the rib 50 prevents rotation of the moving body 61 and the bearing 49, and converts the rotation operation of the feed screw 52 into the front-back operation of the moving body 61. The material of the moving body 61 is polyacetal (POM),
A self-lubricating synthetic resin such as polyamide (PA) and polytetrafluoroethylene (PTFE) powder and various synthetic resins blended with graphite particles can be selected, but polyacetal is preferred because of its low friction coefficient and economical reasons. Is optimal.

The valve body 62 has a substantially disk-shaped flexible valve seat 63 made of synthetic rubber or the like which can abut a valve seat 65 formed in the fluid chamber 56, and a valve seat 63 on the stator 46 side of the valve seat 63. A valve seat holding member 64 made of a rigid body such as a synthetic resin disposed in contact with the surface. The valve seat 63 has no through hole, has an engagement ring portion 63a formed on the outer periphery, and is loosely fitted so as to embrace the valve seat holding member 64. The valve seat holding member 64 has a cylindrical portion 64b that protrudes toward the stator 46, has an inner diameter substantially equal to the outer diameter of the engagement ring portion 61c of the moving body 61, and is formed with a vertical split 64a in the axial direction.
At the end of the cylindrical portion 64b, there is provided an engaging claw 64c which has an inner diameter which is smaller than the outer diameter of the engaging ring portion 61c of the moving body 61 and which is substantially equal to the outer diameter of the cylindrical portion 61d of the moving body 61. 61 and are arranged. Valve seat holding member 6
A gap 69 is provided between the tip of the cylindrical portion 64 b of the fourth member 4 and the spring receiver 61 b of the moving body 61. The material of the valve seat holding member 64 is desirably a gas-resistant synthetic resin material such as polyacetal (POM), polyamide (PA), or polybutylene terephthalate (PBT).

A coil spring 66 having an inner diameter substantially equal to the outer diameter of the cylindrical portion 64b of the valve seat holding member 64 is compressed and held between the movable body 61 and the valve seat holding member 64.

The moving body 61 and the valve body 62 constitute a valve mechanism. At the bottom dead center of the valve-opening side, the open end 49g of the lid 49 and the back surface 64d of the valve seat holding member 64 are formed. The length in the axial direction is set so as to abut, and to have a gap between the lid 49 and the moving body 61.

The sleeve 54 of the rotor 55 and the first bearing 4
8. Polyamide (PA) containing polytetrafluoroethylene (PTFE) and graphite particles between lid 49
Thrust washers 67 and 68 made of a synthetic resin having self-lubricating properties such as are provided.

Next, the operation and operation of the shut-off valve according to the first embodiment will be described.

When the use condition of the gas is not abnormal and the signals from the various sensors do not indicate danger, there is no power supply from the control unit (not shown) of the microcomputer meter, and the shut-off valve is switched to the state shown in FIG.
As shown in (1), the moving body 61 is on the stator 46 side, the valve body 62 keeps the valve open state away from the valve seat 65, and gas can flow.

When the gas usage is abnormal or the signals from the various sensors indicate danger, the control unit of the microcomputer applies a pulsed current having a phase difference to each of the wires 42 of the exciting coil 43. Then, the rotor 55 is rotated forward.
Since the movable body 61 is prevented from rotating by the concave portion 61 e engaging with the rib 50, the feed screw 52
Is converted into a front-back movement of the moving body 61, and the valve body 62 engaged with the moving body 61 has a valve seat 63 with the valve seat 6.
5 and comes into a state shown in FIG.
When the moving body 61 further advances toward the valve seat 65, the coil spring 66 is further compressed, the tip of the cylindrical portion 64b of the valve seat holding member 64 and the spring receiver 61b of the moving body 61 abut, and the valve seat 63 bends. Compressed and finally mobile 6
1 is greater than the thrust of the feed screw 52, and the rotation of the rotor 55 is stopped. Thus, the valve element 62 is connected to the valve seat 6.
5 is urged by a coil spring 66 to shut off gas. FIG. 3 shows the shut-off valve in the closed state.

Thereafter, even if the control unit of the microcomputer meter stops the energization, the rotor 55 holds the state because of the holding torque, so that the valve body 62 is closed by the valve seat 65 biased by the coil spring 66. Keep state.

When the control unit of the microcomputer meter determines that the danger is released from the signals from the various sensors and the danger can be restored, or when the gas user recovers the danger state, the return switch provided on the meter or the remote control panel is operated. In this case, when the gas supplier or the like sends a remote return command by communication, the control unit of the microcomputer meter applies a pulse-shaped current having an opposite phase difference to each of the conductive wires 42 of the exciting coil 43, To reverse rotation. Then feed screw 5
2, the moving body 61 moves to the stator 46 side, the valve body 62 separates from the valve seat 65, and the gas can flow.
The moving body 61 further moves to the stator 46 side, and finally the back surface 64 d of the valve seat holding member 64 of the valve body 62 is
Abuts against the open end 49g of the cylindrical portion 49b, and becomes the bottom dead center of the movement, and the rotation of the rotor 55 stops. Thereafter, even if the control unit of the microcomputer meter stops energization, the rotor 55 holds the state due to the holding torque and holds the valve open state shown in FIG.

Now, this type of shut-off valve is generally attached to a gas meter installed outdoors, and can be used from a temperature exceeding 50 ° C. under direct sunlight in summer to a temperature lower than −20 ° C. in severe winter. Exposed to severe temperature changes. Parts on the gas chamber side such as the gas chamber side of the valve body 62 and the mounting plate 57 are fuel gas which is a low molecular hydrocarbon, and purified impurities such as water, hydrogen sulfide, and sulfur dioxide which are slightly contained in the gas. It will be subjected to such severe temperature changes in an organic environment such as an active gas. Also, the stator 4
6 and the atmosphere side of the mounting plate 57 are exposed to severe conditions such as a high-temperature and high-humidity environment close to the outdoor saturation humidity and dew condensation in the gas meter. Among them, high airtight reliability is required to prevent gas leakage during the service period of the gas meter (generally 10 years).

In the shut-off valve of this embodiment, the mechanism for fixing the stator 46 to the mounting plate 57 is the support frame 59, and the fitting portion 57c for the support frame 59 is formed outside the sealing surface 57e of the mounting plate 57. The fitting portion 57c is completely located on the atmosphere chamber side, such as a fuel gas which is a low molecular hydrocarbon, an active gas which is a fine impurity contained in the gas, such as water, hydrogen sulfide, and sulfur dioxide. No exposure to organic matter environment. In addition, since the caulked portion is formed in a relatively open place, it does not suck up moisture due to capillary action, etc., and even if it is condensed and dried, it dries relatively quickly, so compared to the conventional shut-off valve The mechanism for fixing the stator 46 to the mounting plate 57 is not easily broken.

Further, since the fitting portion 57c is completely on the atmosphere side, even if the fitting portion 57c is damaged due to corrosion or the like, there is no effect on the inside of the sealing surface 57e of the mounting plate 57, and the gas chamber side does not have any effect. Gas leakage does not occur on the atmosphere side.

As described above, according to the present invention, the mechanism for fixing the stator 46 to the mounting plate 57 due to humidity stress, temperature stress, chemical stress, or the like during long-term use is not easily destroyed. It is possible to provide a shutoff valve having high airtight reliability that does not lead to leakage.

Further, in addition to the above configuration, the support frame 5
9, an engagement portion 59b for preventing rotation of the stator 46 is formed.

For this reason, the stator 46 and the mounting plate 57
Even without forming a detent between them, rotation between the stator 46 and the mounting plate 57 can be prevented, and there is no need for unevenness or welding inside the sealing surface 57e of the mounting plate 57, which is a problem for anticorrosion. Due to humidity stress, temperature stress, chemical stress and the like in use, the stator 46
It is possible to provide a shut-off valve having high hermetic reliability which does not cause gas leakage even if the mechanism is fixed to 57.

Incidentally, in FIG.
And the movable body 61 is provided with the concave portion 61e.
A groove may be provided in the second bearing, and a convex portion may be provided on the moving body to engage with the moving body to serve as rotation preventing means. Also, the excitation coil 43,
Although the first electromagnetic yoke 44 and the second electromagnetic yoke 45 are set to two sets, three sets or more sets may be used. Although the seal member 58 is arranged to be compressed in the radial direction, it may be compressed in the axial direction. However, in this case, since the compression ratio of the sealing member 58 is likely to be reduced due to the creep deformation of the collar 49c of the lid 49, the flange 49c or the like is provided at a portion that determines the compression ratio of the sealing member 58 in the axial direction. It is necessary to form such that no synthetic resin is interposed.

Although the thrust bearings are the thrust washers 67 and 68 which are sliding bearings, rolling bearings such as ball bearings may be used. However, in the case of a shut-off valve of a microcomputer meter, the use of a lubricating oil is not preferable because the valve is often left in a state where the valve is opened and stopped for a long period of time. Further, although the valve body 62 and the moving body 61 are separate parts, they may be integrally formed. Although the valve seat 63 embraces the valve seat holding member 64, the valve seat 63 may be fitted at the center, and a central axis is formed in the valve seat holding member to allow the valve seat to pass through the valve seat in an airtight manner. It may be fastened. Although the feed means is a feed screw, it may be a cylindrical cam or the like. Further, although the feeding means and the moving body are the male screw and the female screw, a combination of a worm and a rack may be used.

[0051]

As described above, according to the present invention, the mechanism for fixing the stator to the mounting plate (flange) is a supporting frame, and the fitting portion with the supporting frame is formed outside the sealing surface of the mounting plate. The fitting portion is completely on the atmosphere chamber side, and the fuel gas, which is a low molecular hydrocarbon,
It is not exposed to an organic substance environment such as active gas which is a refined impurity such as water, hydrogen sulfide and sulfur dioxide contained in the gas. In addition, since the caulked portion is formed in a relatively open place, it does not suck up moisture due to capillary action, etc., and even if it is condensed and dried, it dries relatively quickly, so compared to the conventional shut-off valve The mechanism for fixing the stator to the mounting plate is not easily broken.

Since the fitting portion is completely on the atmosphere side,
Even if the fitting portion is damaged due to corrosion or the like, there is no effect on the inside of the sealing surface of the mounting plate, and no gas leaks from the gas chamber side to the atmosphere side. Provide a shut-off valve with high airtight reliability that prevents the mechanism for fixing the stator to the mounting plate from being damaged by humidity stress, temperature stress, chemical substance stress, etc. during long-term use, and does not lead to gas leakage even if it breaks down. be able to.

Further, according to the present invention, in addition to the above-described structure, by forming an engaging portion for preventing rotation of the stator on the support frame, it is possible to form the stator without forming a detent between the stator and the mounting plate. The rotation between the mounting plate and the mounting plate can be prevented, and there is no need for unevenness or welding on the inside of the sealing surface of the mounting plate, which may be a problem for anticorrosion. It is possible to provide a shut-off valve having high hermetic reliability, in which a mechanism for fixing to a mounting plate is not easily broken and gas leakage does not occur even if broken.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a shut-off valve according to a first embodiment of the present invention in an open state.

FIG. 2 is a sectional view of the shut-off valve during a shut-off operation.

FIG. 3 is a sectional view of the shut-off valve in a closed state.

FIG. 4 is a perspective view showing shapes of a mounting plate, a stator, and a support frame of the shutoff valve.

FIG. 5 is a sectional view of a conventional shut-off valve in an open state.

FIG. 6 is a cross-sectional view of another conventional shut-off valve in an open state.

[Explanation of symbols]

 46 Stator 47 Partition wall 55 Rotor 53 Rotating shaft 56 Fluid chamber 57 Mounting plate 57c Fitting portion 57e Seal surface 58 Seal member 59 Support frame 59b Engaging portion 61 Moving body (valve mechanism) 62 Valve body (valve mechanism)

Claims (2)

[Claims] 1. A stator, a rotor disposed inside the stator, a partition wall for keeping the rotor and the stator airtight, a valve mechanism disposed on a rotating shaft of the rotor, and the valve mechanism. Side has a sealing surface with a fluid chamber, a stator is provided on the back surface of this sealing surface, and the rotary shaft is penetrated so that the valve mechanism is located, and a claw-shaped fitting portion is provided on an outer peripheral portion outside the sealing surface. A mounting plate having a sealing member for airtightly holding the mounting plate and the partition, pressing the stator and the partition against the mounting plate in a substantially U-shape and sandwiching the both ends of the mounting plate. A shutoff valve including a support frame fitted to a fitting portion. 2. The shutoff valve according to claim 1, wherein the support frame is provided with an engagement portion for preventing rotation of the stator.