JPH0319661Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a valve drive mechanism in a shutoff valve.

[Prior Art] In a shutoff valve used in combination with a gas leak alarm, a seismic sensor, etc., as shown in FIG. It has a structure in which the valve body 4 is integrally provided at the tip of the housing 1, and the solenoid 2 is driven in response to an electric signal from the above-mentioned alarm, etc., causing the plunger 3 to protrude and the valve body 4
The flow path is blocked by pressing the valve against the nozzle 5 forming the valve seat.

[Problems to be Solved by the Invention] However, with this structure, if the stroke of the valve body 4 is to be long, the stroke of the plunger 3 will inevitably be large. plunger 3
If the stroke becomes large, plunger 3
Since the suction force on the solenoid 2 side decreases in inverse proportion to the square of the distance, a large solenoid must be used, which has the disadvantage of increasing the size of the valve itself.

This invention is intended to solve the above problems, and aims to make it possible to obtain a large drive stroke for the valve body even if the plunger stroke is small.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a shutoff valve comprising a solenoid assembled to a valve housing and a valve body that opens and closes the valve in conjunction with the solenoid. A valve support shaft is erected in the center of the valve body, and this shaft is freely movably penetrated through the center of the plunger,
A lever mechanism is interposed between the bent portion of the lower end of the plunger and the valve support shaft, and the amount of movement of the valve body is amplified with respect to the amount of movement of the plunger according to a lever ratio of the lever mechanism. do.

[Operation] Even if the plunger stroke is small, the valve body is driven with a large stroke according to the lever ratio.

[Example] Hereinafter, an example of this invention will be described in detail using the drawings.

1 to 3 are sectional views showing a shutoff valve according to this invention.

In each figure, 10 is a valve housing, and this valve housing 10 forms a flow path from the inlet 12 side to the outlet 16 side, which crosses at 90 degrees, via a nozzle 14 that constitutes a valve seat.

18 is a phase solenoid fixed on the valve housing 10, and at the lower end of the solenoid 18, a plunger 20 and a valve support shaft 22 penetrating the plunger 20 coaxially and freely protrude into the valve housing 10. A valve body 24 facing the nozzle 14 is integrally provided at the lower end of the valve support shaft 22.

Further, a spring 51 is provided between the valve housing 10 and the valve body 24, and always urges the valve body 24 in the direction of the nozzle 14.

A lever 30 is provided in the flow path on the inlet 12 side of the valve housing 10 and is swingably supported at one end via a fulcrum pin 28. A long hole 32 formed at the other end of the lever 30 It is connected to the valve support shaft 22 by inserting a pin 34 therethrough.

The lower end of the plunger 20 is bent into an L-shape, and a pin 38 protruding from the intermediate portion of the lever 30 is engaged with a long hole 36 formed in the bent end 20a.

Therefore, the lever 30 uses the pin 38 as a point of force to raise and lower the valve support shaft 22, which is the point of action, with a stroke approximately twice as long as the stroke of the plunger 20.

Next, the detailed structure of the phase direction solenoid 18 will be explained.

This solenoid 18 is connected to a yoke 42 fixed on the valve housing 10 via a seal rubber 40.
, a coil 46 inside the yoke 42 and wound around the coil bobbin 44 , a magnetic body 48 and a magnet 49 arranged concentrically between the lower part of the coil 46 and the inner bottom of the yoke 42 , and the coil bobbin 4 .
A post nut 50 is provided on the inner periphery of the upper part of the plunger 4 to attract the plunger 20.

The solenoid 18 having the above configuration overcomes gravity and moves the plunger 20 to the valve support shaft 22 in the non-energized state.
At the same time, it is attracted to the post nut 50, and both are held in the raised position as shown in FIG.

When a cutoff pulse signal is applied to the coil 46 from this state, the magnetic field of the coil 46 forms a magnetic circuit opposite to that of the magnet 49, and the plunger 20 descends together with the valve support shaft 22 due to the repulsive force of the spring 51. , the valve body 24 closes the nozzle 14, as shown in FIG. Valve support shaft 2 in this state
The stroke of No. 2 is approximately twice the stroke of the plunger 20 as described above.

Further, a lateral displacement between the swinging end of the lever 30 and the valve support shaft 22 is absorbed by the displacement of the elongated hole 32 with respect to the pin 34.

To open the valve again from the closed state, a return pulse signal is applied to form a magnetic circuit in phase with the magnet 49.

As a result, the plunger 20 is attached to the post nut 5.
0, and at the same time, the valve support shaft 22 is also pulled up by the action of the lever 30, so that the upper ends meet at the highest position as shown in FIG. 1, and the valve body 24 is held in the open position.

In the embodiment, the stroke of the valve body is set to be approximately twice that of the plunger 20, but this can be changed to a stroke difference according to the lever ratio by changing the force point position of the lever 30.

[Effects of the invention] As explained in detail in the examples above, according to this invention, even if the plunger stroke is small, the valve body can be driven with a large stroke according to the lever ratio, so a large valve opening degree can be set. However, the solenoid itself can be made smaller.

Note that the operating output of the plunger increases in proportion to the lever ratio, but the suction force of the plunger increases by 2 times the distance.
It goes without saying that it is advantageous to make the stroke smaller, considering that it is inversely proportional to the power.

[Brief explanation of the drawing]

1 to 3 show a shutoff valve according to this invention, FIG. 1 is a sectional view of the valve in the open state, FIG. 2 is a sectional view of the valve in the closed state, and FIG. 3 is a sectional view of the valve opening process.
FIG. 4 is a sectional view showing a conventional shutoff valve. 10... Valve housing, 14... Nozzle (valve seat), 18... Compatible solenoid, 20... Plunger, 22... Valve support shaft, 24... Valve body, 30
……lever.

Claims (1)

[Scope of utility model registration request] In a shutoff valve consisting of a solenoid assembled in a valve housing and a valve body that opens and closes the valve in conjunction with the solenoid, a valve support shaft at the center of the valve body is erected, and this is connected to the center of the plunger. A lever mechanism is interposed between the bent portion of the lower end of the plunger and the valve support shaft, and the amount of movement of the valve body is amplified with respect to the amount of movement of the plunger according to the lever ratio of the lever mechanism. A valve drive mechanism for a shutoff valve, characterized in that: