JPH0738779Y2 - solenoid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a solenoid used as an actuator that operates a control valve or the like of a hydraulic / pneumatic device, for example.

(Prior Art) Conventionally, as this type of solenoid, there is one used for an electromagnetic valve as shown in FIG. 4, for example. Ie 10
Reference numeral 0 denotes a cylindrical solenoid main body in which a hollow plunger chamber 101 is formed on the inner peripheral side, and a plunger 102 made of a magnetic material is axially reciprocally inserted in the plunger chamber 101. A center post 102 is attached to one end of the plunger chamber 101, and the plunger 102 is brought into contact with and separated from the center post 103 by exciting the solenoid body 100.

A shim 104 is provided at the contact portion between the plunger 102 and the center post 103, and the plunger 102 and the center post 103 are
The action of infinite magnetic force between 103 is cut.

(Problems to be solved by the invention) However, in the case of the above-mentioned conventional technique, the center post
Since the suction surface between 103 and the plunger 102 is a flat surface, the fluid such as oil interposed between the plunger 102 and the center post 103 acts as a large resistance to the movement of the plunger 102 toward the center post 103. However, there is a problem that the operating speed of the plunger 102 becomes slow and the operating response of the solenoid deteriorates. In particular, when it is used for a hydraulic control valve, the viscosity of the oil increases at low temperatures, so that the escape of the oil is poor and the operation response of the plunger 102 is degraded.

The present invention was made in order to solve the above-mentioned problems of the prior art, and its purpose is to reduce the influence of the fluid interposed between the plunger and the end wall of the plunger chamber as much as possible. It is to provide a solenoid that can improve the performance.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, a plunger chamber is provided inside the hollow hollow solenoid body.
In a solenoid in which a plunger is axially reciprocally inserted into the plunger chamber and the plunger is brought into and out of contact with the end wall of the plunger chamber by energization and de-excitation of the solenoid body, the contact between the end wall of the plunger chamber and the plunger is made. The contact part is provided with a flow path for letting out a fluid interposed between the plunger chamber end wall and the plunger, and the flow path is constituted by a plurality of grooves adjacent to each other, and a boundary between the adjacent grooves. Is linear, and the contact state between the end wall of the plunger chamber and the plunger is line contact.

The end wall of the plunger chamber may be composed of a center post, and the plunger may be magnetically attracted to the center post.

(Operation) In the solenoid having the above structure, when the plunger contacts the end wall of the plunger chamber, the fluid interposed between the plunger and the end wall of the plunger is released from the flow path provided in the plunger contact portion. Therefore, the moving speed of the plunger becomes faster.
Further, since the contact state between the plunger chamber end wall and the plunger is line contact, the contact area is extremely small. Therefore, even if the viscosity of the fluid becomes high, the fluid does not intervene in the contact portion, and the plunger is not affected by the fluid. Therefore, the movement of the plunger becomes faster, and the operation response of the plunger is improved.

(Example) Below, this invention is demonstrated based on the Example shown in figure. 1 to 3 showing a solenoid according to an embodiment of the present invention.
In the drawings, the case where a solenoid is used as an actuator of a solenoid valve will be described in this embodiment as in the conventional example.

The solenoid 1 is composed of an internal hollow solenoid body 3 having a roughly coiled portion 2 and a plunger 5 axially movably inserted into a plunger chamber 4 formed on the inner peripheral side of the solenoid body 3. There is.

The solenoid body 3 accommodates the cylindrical coil portion 2 in a magnetic casing 6, and a magnetic center post 7 is fitted to the inner circumference of the upper half of the coil portion 2. The casing 6 is composed of a cylindrical portion 61 and a lid body 62 that closes the upper end opening of the cylindrical portion 61, and the center post 7 is fixed to a mounting hole 62a provided at the center of the lid body 62. .

On the other hand, a valve body 8 is provided at the end of the casing 6 opposite to the center post 7 so as to face the center post 7. Then, the inner peripheral surface of the coil portion 2, the center post 7,
The space surrounded by the valve body 8 constitutes the plunger chamber 4.

The valve body 8 is provided with two inflow / outflow ports P1 and P2. One of the inflow and outflow ports P1 penetrates the center of the valve body 8 in the axial direction, and the valve seat 9 is provided in the opening of the plunger chamber 4 side, and the valve head of the plunger 5 that functions as a valve body 51 is seated. The other inlet / outlet port P2 is provided from the side surface of the valve body 8 to the plunger chamber 4
It is configured to open to the side.

The plunger 5 is constantly urged in a valve closing direction by a spring 10 interposed between the center post 7 and the plunger 5, and is in a valve closing state in a free state, and the plunger 5 and the center post 7 are separated from each other. . When the solenoid body 3 is excited, the plunger 5 opens against the biasing force of the spring 10, and the plunger 5 moves toward the center post 7 side to move the end face 71 of the center post 7 as the end wall of the plunger chamber 4. Abut.

Between the contact surface between the plunger 5 and the center post 7,
A flow path 11 is provided between the plunger 5 and the center post 7 to allow a fluid such as oil to escape. This channel 11
Is a radial groove on the tip surface of the plunger 5 in this embodiment.
It is composed by forming twelve. Plunger 5
A housing hole 52 for housing the spring 10 is opened at the contact portion with the center post 7, and the radial groove 12 extends outward in the radial direction around the central spring housing hole 52. The grooves 12 are formed so as to be adjacent to each other in the circumferential direction and are provided all around, and the boundary between the adjacent grooves 12 is linear. Although the cross-sectional shape of the groove 12 is a triangle in the illustrated example, various shapes such as a circular arc, a corrugated shape, a rectangular shape and a trapezoidal shape can be selected. Further, although the groove 12 is formed linearly in this example, it may have a curved configuration.

Further, in this embodiment, the groove 12 is provided on the plunger 5 side to form a flow path for releasing the fluid between the contact surfaces of the plunger 5 and the center post 7.
A groove may be provided in 71 to form a flow path. Further, a groove may be provided on both the contact surfaces of the plunger 5 and the center post 7 to form the flow path. Reference numeral 13 is a shim for cutting the action of infinite magnetic force between the plunger 5 and the center post 7.

In the solenoid 1 having the above configuration, the solenoid body 3
When the coil portion 2 is energized, the coil portion 2 is excited and a magnetic path passing through the center post 7, the lid 62, the casing 6 and the plunger 5 is formed. Then, a magnetic attraction force acts between the center post 7 and the plunger 5, the plunger 5 moves toward the center post 7 side against the urging force of the spring 10 and separates from the valve seat 9 to open the valve. Inflow / outflow port P1, P
There is communication between the two.

On the other hand, the plunger 5 collides with the end surface 71 of the center post 7. Here, the plunger 5 is the center post 7
When moving to the side, the fluid interposed between the tip of the plunger 5 and the center post 7 flows toward the outer peripheral side along the radial grooves 12 provided on the front end surface of the plunger 5, and the outer periphery of the plunger 5 Through the gap between the inner circumference of the plunger chamber 4 and the inner circumference of the plunger chamber 4, the fluid smoothly flows to the valve body 8 side, and the resistance of the fluid decreases. Therefore, the plunger 5 moves quickly and the responsiveness is improved. In particular, when a solenoid is used for such an electromagnetic valve, the opening / closing operation of the valve is instantaneously performed, and the switching control characteristic can be improved.

In addition, a radial groove 12 is formed on the contact surface of the plunger 5,
Since the boundary between the adjacent grooves 12 is linear, when the center post 7 and the plunger 5 come into contact with each other, a line contact state is established, and the contact area with the center post 7 becomes extremely small. Therefore, even if the viscosity of the fluid becomes high, the fluid does not intervene in the contact portion between the center post 7 and the plunger 5, so that the plunger 5 is not affected by the fluid. Therefore, the movement of the plunger 5 is accelerated, and the operation response of the plunger 5 is improved. Furthermore, it is possible to abolish Sim 13 as a side effect.

Although the moving speed of the contact portion with the center post when the plunger is magnetically attracted is a problem in the above embodiment, the moving speed when colliding with the end wall of the plunger chamber at the time of elastic recovery due to the spring force is increased. The same applies to the case.

Further, in the above embodiment, the case where the solenoid of the present invention is used for the solenoid valve has been described as an example, but the solenoid valve is not limited to the solenoid valve and can be widely applied as an actuator of various control devices that require actuation response. Is.

(Effects of the Invention) The present invention has the above-described configuration and operation, and since the flow path is formed between the contact surfaces of the plunger and the end wall of the plunger chamber, when the plunger contacts the end wall of the plunger chamber. As a result, the fluid existing in the contact portion can be quickly released through the flow path, and the moving speed of the plunger is increased, so that the operation response can be improved.
Further, since the contact state between the plunger chamber end wall and the plunger is line contact, the contact area is extremely small. Therefore, even if the viscosity of the fluid increases, the fluid does not intervene in the contact portion, and the influence of the fluid on the plunger disappears. Therefore, the movement of the plunger becomes faster, and the operation response of the plunger is improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part of a solenoid according to an embodiment of the present invention, FIG. 2 is a schematic perspective view of a plunger of the solenoid of FIG. 1, and FIG. 3 is a solenoid valve to which the solenoid of FIG. 1 is applied. FIG. 4 is a longitudinal sectional view showing the entire structure of FIG. 4, and FIG. 4 is a longitudinal sectional view of a main part of a solenoid valve using a conventional solenoid. DESCRIPTION OF SYMBOLS 1 ... Solenoid, 2 ... Coil part 3 ... Solenoid body, 4 ... Plunger chamber 5 ... Plunger, 51 ... Valve head, 6 ... Casing, 7 ... Center post 8 ... Valve body, 9 ... Valve seat 10 ... Spring , 11 ... Channel 12 ... Groove, 13 ... Shim

Claims (2)

[Scope of utility model registration request] 1. A plunger chamber is provided inside a hollow hollow solenoid body, and the plunger is axially reciprocally inserted into the plunger chamber. The solenoid body is excited and de-excited to move the plunger into an end wall of the plunger chamber. In the solenoid that comes into contact with and separates from the plunger chamber, the contact portion between the end wall of the plunger chamber and the plunger is provided with a flow path for allowing the fluid interposed between the plunger chamber end wall and the plunger to escape. A solenoid characterized in that the flow path is composed of a plurality of grooves adjacent to each other, the boundary between the adjacent grooves is linear, and the contact state between the end wall of the plunger chamber and the plunger is line contact. 2. The solenoid according to claim 1, wherein the plunger chamber end wall is constituted by a center post, and the plunger is magnetically attracted to the center post.