JPH0641034Y2 - Self-holding solenoid switching valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an electromagnetic directional control valve used in a device that uses fluid pressure or vacuum pressure, and more specifically, to a magnetic force of a permanent magnet after power is cut off. The present invention relates to a self-holding type solenoid operated directional control valve which is held in a switching position by means of.

[Prior Art] Conventionally, as a solenoid directional control valve, a self-holding type in which the switching position is held by the magnetic force of a permanent magnet after the energization is cut off is well known. As shown in FIG. 4, the magnetic frame 1 arranged around the exciting coil is formed in a state where a part thereof is missing, and a permanent magnet is provided between the magnetic frame 1 and the magnetic plate 2 at the missing part. 3 is interposed.

However, when the magnetic path for driving the movable iron core is thus formed through the magnetic frame 1 and the magnetic plate 2 which are mutually divided, and the permanent magnet 3 interposed therebetween,
These divisions increase the magnetic resistance and significantly reduce the efficiency.

Further, if the magnetic frame 1 and the magnetic plate 2 and the permanent magnet 3 are to be fixed in close contact with each other by a fixing means such as adhesion in order to suppress the increase of the magnetic resistance as much as possible, not only the work becomes troublesome, but also This leads to a decrease in reliability.

As a means for solving this problem, a magnet provided between divided fixed iron cores is disclosed in Japanese Patent Application No. 62-132575 (Japanese Patent Laid-Open No. 63-132575).
297883).

However, this electromagnetic switching valve has a problem in that it requires labor to assemble because it is necessary to integrate the fixed iron core and the magnet, which are divided before assembling into the electromagnetic operation unit.

[Problems to be Solved by the Invention] An object to be solved and used by the present invention is to provide a self-holding electromagnetic switching valve in which the permanent magnet can be easily assembled to the electromagnetic operating portion.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides an electromagnetic switching valve in which a valve member driven by an electromagnetic operating unit can switch a flow path between a plurality of ports in a valve unit, A bobbin around which a first coil and a second coil are wound is housed in a magnetic frame of the electromagnetic operation unit, and a cylindrical permanent magnet on the magnetic frame side and a fixed iron core inside the bobbin are provided at one end of a center hole of the bobbin. And the above, and these are brought into close contact with the magnetic frame by a fixing screw of a non-magnetic material screwed to the fixed iron core from the outside of the magnetic frame through a permanent magnet, and a movable iron core for driving the valve member is fitted in the center hole of the bobbin. The first coil is configured to generate a magnetic flux in the same direction as the permanent magnet when energized, and the second coil 23 is configured to generate a magnetic flux in the opposite direction to the permanent magnet when energized.

[Operation] When the fixed iron core and the cylindrical permanent magnet are inserted into the center hole of the bobbin around which the coil is wound, and the fixing screw is screwed into the fixed iron core from the outside of the magnetic frame covering the bobbin through the permanent magnet,
These are closely attached to the magnetic frame.

Therefore, since it is not necessary to integrate the permanent magnet and the fixed iron core before assembling the bobbin, it is easy to assemble the permanent magnet to the electromagnetic operating part, and the magnetic resistance is reduced due to the close contact with the magnetic frame. It

When the first coil is energized, the acting force generated by the combination of the magnetic flux of the permanent magnet and the magnetic flux of the first coil acts on the movable iron core, the movable iron core is attracted to the fixed iron core, and the valve member switches the port. In this state, even if the first coil is de-energized, the movable core is kept attracted to the fixed core by the attraction force of the permanent magnet.

When the second coil is energized, a magnetic flux in the direction opposite to the magnetic flux of the permanent magnet attracting the movable iron core to the fixed iron core is generated, and the attraction force of the movable iron core to the fixed iron core is weakened accordingly, so that the movable iron core is restored. Then, the valve member switches the port. The permanent magnet does not generate an acting force enough to attract the movable iron core in this state, and therefore the movable iron core maintains its position even when the power supply is cut off in this state.

[Embodiment] FIG. 1 shows an embodiment of a self-holding electromagnetic switching valve according to the present invention. This self-holding electromagnetic switching valve is a two-port valve having a valve portion 10 and an electromagnetic operating portion 20 as main components. In the valve section 10, the valve chamber 13 is provided between the input port 11 and the output port 12, and the input port 11 is formed by the valve seat 14 in this valve chamber.
It is opened inside 13.

On the other hand, the electromagnetic operating unit 20 accommodates a bobbin 24 around which a first coil 22 and a second coil 23 are wound in an integrally formed magnetic frame 21 as shown in FIG. At one end
Cylindrical permanent magnet 25 on the side of the magnetic frame 21 and the fixed core inside it
26 and the fixing screw 27 made of a non-magnetic material is screwed into the fixed iron core 26 from the outside of the magnetic frame 21 through the permanent magnet 25 to bring them into close contact with the magnetic frame 21.

The first coil 22 has a permanent magnet 25 when energized.
The magnetic flux is generated in the same direction as the magnetic flux of the second coil 23.
The magnetic flux is generated in the direction opposite to that of the magnetic flux.

The movable iron core 28 slidably inserted into the center hole of the bobbin 24 is provided with a valve member 29 for opening and closing the valve seat 14 at one end, and a return spring 30 is contracted between the fixed iron core 26 and the valve member 29. ing.

In the self-holding type electromagnetic switching valve, the permanent magnet 25 is fitted in the center hole of the bobbin 24.
There is no need to divide 21 and performance is improved by improving magnetic efficiency.

In addition, the fixing screw 27 allows the separate permanent magnet 25 and the fixed iron core 26 to be in close contact with the magnetic frame 21.
It is easy to assemble to 20, and the magnetic resistance can be reduced.

Next, the operation of the self-holding electromagnetic switching valve having the above configuration will be described.

When the valve member 29 closes the valve seat 14 by the urging force of the return spring 30, when the first coil 22 is energized, the acting force generated by the combination of the magnetic flux of the permanent magnet 25 and the magnetic flux of the first coil 22. Acts on the movable iron core 28, and the movable iron core 28 is attracted to the fixed iron core 26 against the biasing force of the return spring 30. As a result, the valve member 29 opens the valve seat 14, and the input port 11 and the output port 12 communicate.

Even if the first coil 22 is de-energized in this state, the movable core
28 holds the state of being attracted to the fixed iron core 26 by the attraction force of the permanent magnet 25.

Next, when the second coil 23 is energized, a magnetic flux in a direction opposite to the magnetic flux of the permanent magnet 25 attracting the movable iron core 28 to the fixed iron core 26 is generated, and the movable iron core 28 relative to the fixed iron core 26 is accordingly generated.
Since the attraction force of is weakened, the movable iron core 28 is returned by the urging force of the return spring 30, and the valve member 29 closes the valve seat 14.
The communication between the input port 11 and the output port 12 is cut off. The permanent magnet 25 does not generate an acting force enough to attract the movable iron core 28 in this state, and therefore the movable iron core 28 holds its position even when the power supply is cut off in this state.

FIG. 2 shows a modification of the self-holding type electromagnetic switching valve, in which a step portion 32A with which the fixed iron core 26 engages is provided in the center hole of the bobbin 24A, and when the movable iron core 28 is attracted to the fixed iron core 26. The impact on the permanent magnet 25 is suppressed from being directly applied to the permanent magnet 25.

[Advantages of the Invention] In the self-holding electromagnetic switching valve of the present invention having the above configuration, the permanent magnets can be closely attached to the magnetic frame by the fixing screws by properly disposing the cylindrical permanent magnet and the fixed iron core. Can be easily assembled to the electromagnetic operation unit, and the magnetic resistance can be reduced thereby, and the performance can be improved by improving the magnetic efficiency.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of an embodiment of the present invention, FIG. 2 is a cross-sectional view of a main part of a modification thereof, FIG. 3 is a perspective view of a magnetic frame in the above embodiment, and FIG. 4 is a conventional magnetic frame. It is a perspective view. 10 …… Valve part, 11 …… Input port, 12 …… Output port, 20 …… Electromagnetic operation part, 21 …… Magnetic frame, 22 …… First coil, 23 …… Second coil, 24,24A …… Bobbin, 25 …… Permanent magnet, 26 …… Fixed iron core, 28 …… Movable iron core, 29 …… Valve member.

Claims (1)

[Scope of utility model registration request] 1. An electromagnetic switching valve capable of switching a flow path between a plurality of ports in a valve portion by a valve member driven by the electromagnetic operating portion, wherein a first coil and a first coil are provided in a magnetic frame of the electromagnetic operating portion. A bobbin wound with two coils is housed, a cylindrical permanent magnet on the magnetic frame side and a fixed iron core inside the bobbin are disposed at one end of the center hole of the bobbin, and these are passed from outside the magnetic frame through a permanent magnet. A non-magnetic material fixing screw screwed to the fixed iron core is brought into close contact with the magnetic frame, and a movable iron core for driving the valve member is fitted in the center hole of the bobbin, and the first coil is energized in the same direction as the permanent magnet. The self-holding electromagnetic switching valve is characterized in that the second coil is configured to generate a magnetic flux in the opposite direction to the permanent magnet when energized.