JPS5821079A - Actuator - Google Patents

Abstract

PURPOSE:To improve safety of the device in such a way that a relief valve which is opened when pressure in the pressure chamber goes up beyond the determined maximum value is inserted into a path which links the side of a pressure chamber and a reservoir chamber in an electromagnetic pump to actuate an actuator. CONSTITUTION:When pressure on the side of a pressure chamber 17 abnormally goes up through clogging of an orifice 20, a relief valve 21 which is connected in parallel with the orifice 20 is opened, and working oil on the side of the pressure chamber 17 is returned through the relief valve 21 to a reservoir chamber 14. In consequence, if the pressure which is opened by means of the relief valve 21 is set to its proper value, the pressure on the side of the pressure chamber 17 may not abnormally go up, and when an electromagnetic pump 13 comes to a stop, a bypass valve 24 is opened forthwith, and opening of pressure on the side of the is done momentarily.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an actuator that drives a valve or the like using fluid pressure generated by an electromagnetic pump.

It is possible to generate the desired pressure in the pressure chamber by forming a circulation path in which the hydraulic oil in the storage chamber is pumped into the pressure chamber by the action of an electromagnetic pump, and then returned to the storage chamber via the oriice. By displacing the responsive body with this pressure, it is possible to drive valves, etc. In this type of actuator, if the opening area of the orifice is constant, the pressure generated in the pressure chamber will correspond to the discharge flow rate of the electromagnetic pump, and it is also possible to proportionally control the responsive body. If the orifice is clogged due to adhesion of , fl, etc., the pressure in the pressure chamber will not decrease even if the electromagnetic pump is stopped, resulting in a dangerous situation such as the valve remaining open.

This kind of danger can be avoided by forming a bypass path connecting the pressure chamber and the storage chamber, and installing a bypass valve in this bypass path that opens when the electric pump is not operating. can do. However, since the pressure inside the pressure chamber acts to push the pias valve toward the closed position,
If the pressure within the pressure chamber becomes abnormally high for some reason, the pressure within the pressure chamber may not decrease even if the electromagnetic pump is stopped.

The present invention aims to provide an actuator that can reliably open the bypass valve and release the pressure in the pressure chamber when the electromagnetic pump is stopped by always maintaining the pressure in the pressure chamber below a predetermined upper limit value. The purpose is

Next, an embodiment of the present invention will be described with reference to the drawings.The flow rate control device shown in Fig. 0 includes a pressure generating section that generates hydraulic pressure, a converting section B that converts this hydraulic pressure to 1-2 levels, and a flow control device shown in FIG. It is composed of a control section C driven by a conversion section B. This example shows a flow control device configured to control the flow rate of fuel gas supplied to a combustion chamber, such as a water heater.

The pressure generating section A has an electromagnetic lamp 13 consisting of a coil 11 and an actuating section 12 passing through the center hole thereof. This electromagnetic pump 13 works to suck the hydraulic oil contained in the reservoir 1j14 from the passage 15 into the oscillating part 12, and then forcefully feed it into the pressure 117 through the passage 16. Pressure I again! 17 also communicates with a second pressure chamber 19 via a passage 18. Furthermore, the pressure chamber 17 is also connected to the storage chamber 14 by a passage 4 having orifice addition and relief valves 21 inserted in parallel with each other. Therefore, when the electromagnetic I pump 3 operates, the hydraulic oil is stored in the storage chamber 14.
From the passage 15, the operating section 12, the passage 16. A slight accumulation occurs in the path returning to the storage chamber 14 through the pressure chamber 17 and the passage 22, and a pressure corresponding to the discharge flow rate of the electromagnetic lamp 13 is generated in the pressure chambers 17 and 19 by the action of the orifice addition. Further, if the pressure in the pressure chamber 1719 is below a predetermined maximum value, the relief valve 21 remains closed.

On the other hand, a bypass AM 23 is formed that connects the suction side passage 15 and the discharge side passage 16 of the electromagnetic I/P 13, and in this bypass passage n, the electromagnetic I/P 13 is operated normally. A bypass valve U is provided, which is held in the closed position only by the inverter. Therefore, if the operation of the electromagnetic 4 pump 13 stops after the pressure inside the pressure chamber 17 rises, the bino mother valve 2
4 immediately moves to the open position, thereby instantly releasing the pressure within the pressure chamber 17.

The converting section B is provided adjacent to the pressure generating section A.

It has two reaction bodies 31 and 32. First response body 3
1 is in contact with the inside of the pressure chamber 17 via a bellows frame, is fixed to the tip of a rod movable in the axial direction, and is biased toward the pressure chamber 17 by a spring member. The second response body 32 is in contact with the pressure IE19 via a velor M), and is supported by the tip of the rod that is movable in the axial direction, and is directed into the pressure IE19 by a spring. is being pressed down.

Therefore, when the pressure in the pressure chambers 17 and 19 rises, the responsive body 31 and the mouse move against the springs and a, respectively, and when the pressure decreases, they return to their original positions. A displacement transformation is performed. The pressure receiving area of the second reaction body 32 is smaller than that of the first reaction body 31, and therefore the pressure at which the second reaction body 32 starts to be displaced is higher than that of the first reaction body 31.

IIIJlliIlsC is entrance passage 41, communication passage 4
It has two openings and an outlet passage, and preferably a regulator (not shown) is provided within the connecting passage. Entrance passage 41
The connecting passage and the valve seat communicate with each other through the center hole of the valve seat, and the opening/closing valve seat is pressed into contact with the valve seat by the action of spring casting. A valve rod 47 supporting the on-off valve 45 is in contact with the tip of the rod. The communication passage 42 and the outlet passage 43 communicate with each other through the center hole of the valve seat 48, and a proportional valve 50 is pressed against the valve seat 48 by a spring 49. A valve rod 51 provided at the center of the proportional valve (part) is in contact with the tip of the rod 36 at one end thereof. By moving the proportional valve between a fully closed position in close contact with the valve seat and a fully open position farthest from the valve seat, the controlled fluid flowing from the communication passage 42 to the outlet passage 42, for example, a fuel bus The flow rate can be controlled proportionally.

In the actuator configured as described above, if the pressure in the pressure chamber 17@ increases abnormally due to some reason, for example, the orifice is clogged.

A relief valve 21 connected in parallel with the orifice is opened, and the hydraulic oil on the pressure chamber 17 side returns to the storage chamber 14 through the relief valve 21. Therefore, if the pressure at which the relief valve 21 opens is set to an appropriate value, the pressure in the pressure chamber 1711J will not rise abnormally, and when the electromagnetic pump 13 stops, the binoculars valve 24 will open immediately. Pressure II 171
1 pressure release occurs instantaneously.

As described above, according to the present invention, a relief valve that opens when the pressure in the pressure chamber abnormally increases beyond a predetermined maximum value is inserted in the passage connecting the pressure chamber side and the storage chamber. This eliminates the inconvenience of abnormally rising pressure in the chamber and making it difficult to open the bypass valve, and when the electromagnetic pump stops, the pressure in the pressure chamber is instantly released, greatly improving safety.

[Brief explanation of the drawing]

The figure is a longitudinal sectional view of an actuator according to an embodiment of the present invention. A.-Pressure generation section, B-conversion section, C-control section, 11-coil, 12... actuation section, 13... electromagnetic pump, 14
-Storage wwi, 17, 19-pressure chamber, addition orifice, 21-relief valve, vane...bypass passage, 24...pinos valve, 31° 32-wide moving body, 41-artificial passage, 4
2-Connecting passage, 43--Outlet passage, 44-Valve seat, 45-
On-off valve, 48-valve seat, separate...proportional valve.

Claims (1)

[Claims] an electromagnetic pump that pumps the working fluid in the storage chamber to the pressure chamber;
A passage having an orifice for returning the working fluid from the pressure chamber side to the storage chamber, a response body that is displaced in accordance with the pressure generated in the pressure chamber, and a passageway connecting the pressure chamber side and the storage chamber. Binori J path set up in and Joki electromagnetic?
A pi that blocks the passage of the Pino parable of the ancient times only when the pump is in operation.
An actuator comprising: a four-way valve; and a relief valve that is connected to the orifice and the pot row and opens when the pressure in the pressure chamber rises above a set value.