JPH0725496Y2 - Valve open / close position detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a valve opening / closing position detecting device for detecting the open / closed state of a valve used in a gas pipe or the like installed outdoors.

[Conventional technology]

Remotely control the valves in the gas pipes installed outdoors,
Known devices for detecting the open / closed state are shown in FIGS. 5 and 6.

In FIGS. 5 and 6, the valve body 1 is connected to the gas pipe by means of flanges 2 and 3 provided at both ends thereof. An actuator 4 for opening and closing a valve (not shown) in the valve body 1 by air pressure is attached to the upper portion of the valve body 1. Reference numeral 5 is an operating shaft for manually operating the valve of the valve body portion 1. The distal end 5a is provided with two parallel planes by a notch so that it can be rotated by a tool such as a spanner. 5 also rotates when the actuator 4 is operated remotely. An L-shaped metal fitting 6 is attached to the upper part of the actuator 4.
A limit switch 7 is fixed to the metal fitting 6. An arm 8 is fixed to the operation shaft 5, and the arm 8 is in contact with the arm 7a of the limit switch 7.

When air pressure is applied to the actuator 4 attached to the upper portion of the valve body 1, the operation shaft 5 rotates to open or close the valve. At this time, the arm 8 interlocks with the rotation of the operation shaft 5, and the arm 8 presses the arm 7a, whereby the limit switch 7 opens and closes. The opening / closing operation signal of the limit switch 7 is taken out as a valve opening / closing signal.

[Problems to be solved by the device]

The valve opening / closing position detecting device in the conventional device described above uses a limit switch to detect the opening / closing position. Since this limit switch has mechanical contacts, there is a problem in contact reliability, and there is a possibility that gas may float around the valve due to gas leakage. There is a risk that the sparks generated when opening and closing may ignite the gas. Further, since the valve is installed outdoors, the limit switch arm freezes in winter and normal detection cannot be performed.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a highly reliable valve open / closed position detection device that eliminates the above-mentioned drawbacks of the conventional device and can reliably detect the open / closed state of the valve.

[Means for Solving the Problems]

In order to achieve the above object, the present invention provides an operation shaft that rotates in association with opening and closing of a valve, and a detection plate that has at least one slit and that moves in association with rotation of the operation shaft. , Having a light emitting end and a light receiving end sandwiching the detection plate, and arranged so that an optical axis formed between the light emitting end and the light receiving end is orthogonal to the surface of the detection plate. A pair of optical fiber type photoelectric detectors, and light passing through an optical axis formed between the light emitting end and the light receiving end of one optical fiber type photoelectric detector when the valve is in the open position. Light passing through the slit and passing through the optical axis formed between the light emitting end and the light receiving end of the other optical fiber type photoelectric detection device is blocked by the detection plate, and the valve is in the closed position. At this time, it is formed between the light emitting end and the light receiving end of one optical fiber type photoelectric detection device. Light passing through the optical axis is shielded by the detection plate, and light passing through the optical axis formed between the light emitting end and the light receiving end of the other optical fiber photoelectric detection device passes through the slit, It is characterized in that the two sets of optical fiber type photoelectric detectors are arranged respectively.

[Action]

The present invention has two sets of optical fiber type photoelectric detection devices for detecting the open and closed positions of the valve, and one of the optical fiber type photoelectric detection devices is turned on at the open or closed position of the valve. The light-emitting end and the light-receiving end of the optical fiber type photoelectric detector cannot be detected due to dirt or the like. Since the fiber type photoelectric detection device is turned on, it can be prevented by inspecting the received light amount of the light projected from the light emitting end and received at the light receiving end each time it is turned on. In addition, the valve opens
A failure state such as stopping at a halfway position outside the closed position can be detected by simultaneously turning off the optical fiber type photoelectric detection device for a predetermined period.

〔Example〕

Next, an embodiment of the present invention will be described in detail with reference to the drawings. 1 to 4 show an embodiment of a valve opening / closing position detecting device according to the present invention. The same parts as those of the conventional example shown in FIGS. 5 and 6 are designated by the same reference numerals. .
FIG. 1 is a schematic configuration diagram of a valve opening / closing position detecting device. First, the outline will be described with reference to FIG.

In FIG. 1, a detection plate 10 having an L-shaped cross section having two slits 11 and 12 in an arcuate vertical arm 10b is attached to the operation shaft 5 of the valve by the horizontal arm 10a.
Moves left and right by the rotation of the operation shaft 5. This detection plate 10
The light emitting ends 13a and 14a and the light receiving ends 13b and 14b arranged to face each other so as to sandwich the vertical arm 10b of the optical fiber 17a,
Amplifier unit 13A, 14A connected via 17b, 18a, 18b
An optical fiber type photoelectric detection device 40 provided with is provided, and the light emitting end portions 13a, 14a and the light receiving end portions 13b, 14b of the optical fiber type photoelectric detection device 40 are in the vicinity of a valve in which gas is likely to float. Installed, the amplifier unit 13A, 14A of the optical fiber type photoelectric detection device 40 is located at a place distant from the valve installation position,
Or, if it cannot be installed in a place away from the valve installation location, it will be installed in an explosion-proof box.

Amplifier unit 13A of the optical fiber type photoelectric detection device 40,
The 14A converts, for example, an electric signal from the central monitoring room into an optical signal, transmits the optical signal to the light emitting ends 13a and 14a through the optical fibers 17a and 18a, and projects the light from the light emitting ends 13a and 14a. . Light receiving ends 13b, 14b for receiving light from the light emitting ends 13a, 14a
The light reception signal from is input to the amplifier units 13A and 14A via the optical fibers 17b and 18b, and the light reception signals are converted into electric signals again by the amplifier units 13A and 14A and sent to the central monitoring room. When the valve is open, as shown in the figure, the slit 12 of the vertical arm 10b of the detection plate 10 faces the light emitting end 14a and the light receiving end 14b, and is located between the light emitting end 14a and the light receiving end 14b. The light passing through the optical axis 16 formed in the slit 12 and the ON signal is output from the amplifier unit 14A, and the light passing through the optical axis 15 formed between the light emitting end 13a and the light receiving end 13b. Is shielded from light by the vertical arm 10b of the detection plate 10 and an off signal is output from the amplifier unit 13A. Then, when the bulb is rotated from the open position to the closed position, the light emitting ends 13a and 13b are formed.
The light passing through the optical axis 15 formed by and passes through the slit 11 to output an ON signal from the amplifier unit 13A, and the light passing through the optical axis 16 formed by the light emitting end 14a and the light receiving end 14b is The off arm signal is output from the amplifier unit 14A while being shielded from light by the vertical arm 10b of the detection plate 10.

As described above, in the present invention, two sets of optical fiber type photoelectric detectors are used to detect the open and closed positions of the valve.

Next, the configuration of the main part of the present invention will be described with reference to FIGS. 2 and 3 showing the vicinity of the operation shaft 5 and the detection plate 10 which rotate in conjunction with the valve.

2 and 3, a ring-shaped attachment 19 is attached to the operation shaft 5 with a screw 20, and an L-shaped detection plate 10 having a horizontal arm 10a is attached to the upper surface of the attachment 19 at its upper surface. It is attached by a screw 21 so as to sandwich the operation shaft 5 in a crotch position. The vertical arm 10b of the detection plate 10 is formed in an arc shape, and as is apparent from FIG. 4, the optical axis formed by the light emitting ends 13a, 14a and the light receiving ends 13b, 14b at both ends of the vertical arm 10b. 15,1
Slits 11 and 12 through which light passing through 6 can pass are provided. The positions of these two slits 11 and 12 are two optical axes 15 and 16
Does not face the slit position at the same time, and when the operation axis 5 is in the valve open position, the light passing through the optical axis 16 passes through the slit 12 and the light passing through the optical axis 15 is blocked by the vertical arm 10b, and the operation is performed. When the axis 5 is in the valve closed position, the light passing through the optical axis 15 passes through the slit 11 and the light passing through the optical axis 16 passes through the vertical arm 10b.
It is provided so as to be shielded from light.

The optical fiber 17a, 17b, 1 to the amplifier unit 13A, 14A described above
Light emitting ends 13a, 14a and light receiving end 1 connected via 8a, 18b
Mounting fittings having threads on their outer circumferences are respectively fitted in the 3a and 14b. The fermentation end 13a and the light receiving end 13b are
As is apparent from FIG. 3, the U-shaped metal fittings 22A are respectively attached to the leg pieces, and the light emitting end portion 14a and the light receiving end portion 14b are U-shaped.
U-shaped metal fitting 22B having the same structure as the U-shaped metal fitting 22A (see FIG. 2)
It is attached to each leg. Each U-shaped metal fitting
22A and 22B have screws 27 attached to the upper side of a mounting bracket 24 having a U-shaped cross section attached to the actuator 4 with screws 23 on the lower side.
(The screw 27 of the U-shaped metal fitting 22B is not shown in the drawing), and the light-emitting end portion 13a and the light-receiving end portion 13B and the U-shaped metal fitting are respectively attached to the legs of the U-shaped metal fitting 22A. The light emitting end portion 14a and the light receiving end portion 14b, which are respectively attached to the leg pieces of 22B, are arranged to face each other with the vertical arm 10b of the detection plate 10 interposed therebetween. Each of the leg pieces of the U-shaped metal fittings 22A, 22B is provided with a light-shielding piece that is bent toward the leg pieces facing each other, and this light-shielding piece prevents the optical fiber type photoelectric detection device from malfunctioning due to outside light. ing.

Next, the operation of the valve opening / closing position detecting device of the present invention will be described.

The two slits 11 and 12 of the detection plate 10 do not output the ON signals from the two amplifier units 13A and 14A at the same time, and one of the amplifier units 13A and 14A is open or closed at each position. Is provided so that an ON signal is output from the. Therefore, for example, as shown in FIG. 2, when the slit 12 provided in the detection plate 10 attached to the operation shaft 5 faces the optical axis 16 when the valve is in the open position, the slit 12 passes through the optical axis 16. Since the light passes through the slit 12, the ON signal is output from the amplifier unit 14A, and the light passing through the optical axis 15 is blocked by the vertical arm 10b of the detection plate 10, so the output of the amplifier unit 13A is OFF. . In this way, the output of amplifier unit 14A is turned on,
When the output of the amplifier unit 13A is off, the "open" of the valve can be detected. When the valve rotates from the open position to the closed position, that is, when the operation shaft 5 rotates in the counterclockwise direction in FIG. 2, the detection plate 10 also moves in the counterclockwise direction in conjunction with the rotation of the operation shaft 5. When the detection plate 10 starts moving in the counterclockwise direction, all the light passing through the optical axes 15 and 16 is detected.
The light is shielded by. After that, when the valve rotates to the closed position and stops at the position where the slit 11 of the detection plate 10 coincides with the optical axis 15, the light passing through the optical axis 15 passes through the slit 11 so that an ON signal is output from the amplifier unit 13A. Moreover, since the light passing through the optical axis 16 is blocked by the vertical arm 10b of the detection plate 10, the output of the amplifier unit 14A is off.
The output of this amplifier unit 13A is on, amplifier unit 1
When the 4A output is off, valve "open" can be detected.

As described above, the optical fiber type photoelectric detection device including the light emitting end 13a, the light receiving end 13b and the amplifier unit 13A,
Two sets of optical fiber type photoelectric detection devices, that is, a light emitting end part 14a, a light receiving end part 14b, and an optical fiber type photoelectric detection device consisting of an amplifier unit 14A are used. Since the ON signal is output from either one of the pair of optical fiber type photoelectric detection devices, the following failure states can be detected.

If the valve stops at a halfway position that is out of the open or closed position due to a failure of the actuator 4,
Both outputs from the two sets of optical fiber type photoelectric detection devices are turned off. Therefore, the outputs of the two sets of optical fiber type photoelectric detectors are simultaneously turned off for a predetermined time, that is, after the outputs of the two sets of optical fiber type photoelectric detectors are both turned off,
If the OFF state continues after the time required for the valve to rotate from the open or closed position to the closed or open state, it can be detected that the valve has stopped at a halfway position. .

Either one of the optical fiber photoelectric detectors is turned on at the open / closed position of the valve, so it is necessary to detect the amount of light received from the light emitting ends 13a, 14a to the light receiving ends 13b, 14b during the on period. As a result, it is possible to prevent the end faces of the light receiving ends 13a, 14a or the light receiving ends 13b, 14b from becoming undetectable due to dirt or the like.

[Effect of device]

As described above, according to the present invention, an operation shaft that rotates in association with opening / closing operation of a valve, and a detection plate that has at least one slit and that moves in association with rotation of the operation shaft. , Having a light emitting end and a light receiving end sandwiching the detection plate, and arranged so that an optical axis formed between the light emitting end and the light receiving end is orthogonal to the surface of the detection plate. A pair of optical fiber type photoelectric detectors, and light passing through an optical axis formed between the light emitting end and the light receiving end of one optical fiber type photoelectric detector when the valve is in the open position. Light passing through the slit and passing through the optical axis formed between the light emitting end and the light receiving end of the other optical fiber type photoelectric detection device is blocked by the detection plate, and the valve is in the closed position. At this time, it is formed between the light emitting end and the light receiving end of one optical fiber type photoelectric detection device. The light passing through the optical axis is shielded by the detection plate, and the light passing through the optical axis formed between the light emitting end and the light receiving end of the other optical fiber photoelectric detection device passes through the slit. Therefore, unlike the conventional device, there is no contact failure like a mechanical contact switch, and the life is long, so the reliability is high. In addition, unlike the reed switch, no sparks are generated when the contacts are opened or closed, so there is no risk of ignition of floating gas due to gas leaks, etc., and safety is extremely high. Furthermore, two sets of light are open and closed at the valve position. Since one of the fiber-type photoelectric detectors is always on, the amount of light received during the on-state can be used to detect dirt on the light-emitting end of the optical-fiber photoelectric detector or the end face of the light-receiving end. It has an excellent effect that it can be detected, and further, an abnormality that the valve stops at a halfway position due to a failure of the actuator or the like can be detected.

[Brief description of drawings]

1 to 4 show an embodiment of a valve opening / closing position detecting device according to the present invention. FIG. 1 is a schematic configuration diagram thereof, FIG. 2 is a plan view of essential parts, and FIG. 3 is a side view of essential parts. FIG. 4 is a front view of the detection plate, FIGS. 5 and 6 show a conventional valve opening / closing position detecting device, FIG. 5 is a side view, and FIG. 6 is a front view. 5: Operation axis, 10: Detection plate, 11, 12: Slit, 13A, 14A: Amplifier unit, 13a, 14a: Light emitting end, 13b, 14b: Light receiving end, 1
5, 16: Optical axis, 40: Optical fiber type photoelectric detector.

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Claims (1)

[Scope of utility model registration request] 1. A detection plate having an operation shaft that rotates in association with opening / closing operation of a valve, at least one slit, and a plate that moves in conjunction with rotation of the operation shaft, and a detection plate sandwiched between the detection plates. Two sets of optical fiber type photoelectric converters having a light emitting end and a light receiving end, and arranged so that an optical axis formed between the light emitting end and the light receiving end is orthogonal to the surface of the detection plate. With a detection device, when the valve is in the open position, the light passing through the optical axis formed between the light emitting end and the light receiving end of one optical fiber type photoelectric detection device passes through the slit, Light passing through the optical axis formed between the light emitting end and the light receiving end of the other optical fiber type photoelectric detection device is shielded by the detection plate, and one optical fiber type is used when the bulb is in the closed position. The light passing through the optical axis formed between the light emitting end and the light receiving end of the photoelectric detection device is detected as The two sets of optical fiber type photoelectric detection devices are shielded by the optical fiber type photoelectric detection device and the light passing through the optical axis formed between the light emitting end and the light receiving end of the other optical fiber type photoelectric detection device passes through the slit. A valve opening / closing position detecting device characterized in that each device is arranged.