JPH0447927Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention fixes the movable core by winding an electromagnetic coil around a movable core arranged in correspondence with a fixed core, and energizing the electromagnetic coil. It relates to a movable core in an electromagnetic actuator that is operated by adhering to the core, and is particularly used for operating a valve body in a solenoid valve or for an electromagnetic drive device.

[Conventional technology]

Conventionally, a guide ball is placed between the outer periphery of a movable core and a guide tube that guides it to maintain a side gap between the outer periphery of the movable core and the inner periphery of the guide tube and to guide linear motion. This method includes a method in which a special holder is used to hold the guide ball, and a method in which a holding hole is bored approximately perpendicularly to the outer circumferential surface of the movable iron core.

[The problem that the idea aims to solve]

According to the first method, it is necessary to prepare a cage specially, which increases the number of products, and also requires mounting work to place the cage on the movable core, which increases manufacturing costs, so it is not preferable. Not only that, but changing the side gap requires preparing a new retainer, which is difficult to manage.

In addition, according to the second method, the movable core itself can be manufactured only by machining with a lathe, but hole machining with a drill press is required for machining the holding hole, which increases the number of manufacturing steps and is not preferred. do not have.

[Means to solve problems]

The purpose of the movable core in the electromagnetic actuator of the present invention is to provide a movable core that does not require new parts, is easy to process, and is inexpensive. A plurality of vertical grooves are bored on the outer periphery of the movable core along the axial direction, and circumferential grooves that are substantially perpendicular to the vertical grooves are bored in the outer circumference of the movable core, and the vertical grooves intersect with the circumferential grooves. A guide ball is placed in the groove and comes in contact with the inner surface of the guide tube.

[Effect]

The guide ball is guided in the intersecting groove of the vertical groove and the circumferential groove, and a part of the outer periphery of the guide ball is guided on the inner surface of the guide tube, so that the movable iron core is surely slid and guided inside the guide tube. It is something that can be maintained.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a movable core in an electromagnetic actuator according to the present invention will be described below with reference to FIGS. 1 to 3.

1 is a guide tube with an open top and bottom;
A fixed iron core 2 is fixedly arranged in the upper opening, and a movable iron core 3 is movably arranged in the guide cylinder 1 corresponding to the fixed iron core 2 from the lower opening of the guide cylinder 1. Further, a coil bobbin 4 is arranged on the outer periphery of the guide cylinder 1, and an electromagnetic coil 5 is wound around the outer periphery of the coil bobbin 4.

Note that 6 is a spring compressed between the fixed core 2 and the movable core 3, and 7 is a cup-shaped coil bonnet surrounding the outer periphery of the electromagnetic coil 5. is caulked.

The above is a conventionally known electromagnetic actuator, and the movable core according to the present invention has the following structure in order to achieve the above object.

That is, 10 is a vertical groove bored vertically in the figure on the outer circumference 3A of the movable core 3 along the longitudinal axis XX of the movable core 3. It is preferable that a plurality of angles are provided in the cross section of No. 3 and provided in an equal angular range.

In this example, three vertical grooves 10 were provided at 120 degree intervals. Furthermore, the outer circumference 3 of the movable iron core 3
A circumferential groove 11 that is substantially perpendicular to the vertical groove 10 is bored in A, and it is desirable to provide a plurality of circumferential grooves 11, and in this embodiment,
Placed above and below.

Therefore, a vertical groove 10 is formed on the outer circumference 3A of the movable iron core 3.
A plurality of intersecting grooves 12 are formed between the circumferential groove 11 and the circumferential groove 11, and in this embodiment, six intersecting grooves 12 are formed. Guide balls 13 each having a diameter φd are disposed within each of the intersecting grooves 12, and a portion of the spherical surface of the guide balls 13 slightly protrudes from the outer circumference 3A of the movable iron core 3. This protruding distance is set appropriately as necessary, but in order to make a part of the spherical surface of the guide ball 13 protrude from the outer circumference 3A of the movable iron core 3, the groove width a of the vertical groove 10 and The groove width b of the circumferential groove 11 must be set within the following range.

d sin45°<a<d d sin45°<b<d In this manner, the movable core 3 is disposed within the guide tube 1 with a plurality of guide balls 13 disposed on the outer circumference 3A of the movable core 3.

When a magnetic force is generated by the electromagnetic coil 5, the movable core 3 and the guide cylinder 1 slide through the guide ball 13, and are attracted to the fixed core 2 against the spring force of the spring 6. On the other hand, when the magnetic force generated by the electromagnetic coil 5 is eliminated, the movable iron core 3 is returned to its original position by the spring force of the spring 6.

[Effect of idea]

As described above, the movable core in the electromagnetic actuator according to the present invention provides the following effects.

The sliding movement between the movable core and the guide cylinder is performed via guide balls, and the guide balls are arranged in a plurality of intersecting grooves formed evenly around the outer circumference of the movable core. However, the movable iron core does not tilt relative to the guide tube, and the dynamic characteristics of the movable core can be maintained smoothly.

In particular, when arranging the guide ball on the movable core, if the vertical grooves are made of drawn material and the circumferential grooves are lathe-machined by machining the movable core itself, the circumferential grooves can be machined at the same time in the same process. Since there is no need to use a special cage like in the past or to process the guide ball using a drilling machine, milling machine, etc., it is extremely easy to process and can be manufactured at low cost. It has become.

The protrusion dimension of the guide ball from the outer circumference of the movable core can be freely adjusted by selecting the widths of the vertical groove and the circumferential groove, so it is possible to adjust the dimension of the guide ball from the outer circumference of the movable iron core. It is extremely easy to set the side gap and the fluid escape above and below the movable core.

[Brief explanation of the drawing]

The figures show one embodiment of the movable core in the electromagnetic actuator according to the present invention. Figure 1 is a longitudinal sectional view of the electromagnetic actuator, Figure 2 is a top plan view of the movable core, and Figure 3 is a top plan view of the movable core. is a side view taken in the direction of the arrows in FIG. 2; 1... Guide tube, 2... Fixed core, 3... Movable core, 3A... Outer circumference, 5... Electromagnetic coil, 10
... Vertical groove, 11 ... Circumferential groove, 12 ... Cross groove, 1
3...Guidance ball.

Claims (1)

[Claims for Utility Model Registration] A movable core 3 is movably arranged in correspondence with a fixed core 2 disposed in a part of the guide tube 1, and an electromagnetic coil 5 is wound around the outer periphery of the guide tube 1. In an electromagnetic actuator that operates a movable core 3 by electromagnetic force generated in a coil 5, a plurality of vertical grooves 10 are bored on the outer periphery of the movable core 3 along the longitudinal axis direction XX of the movable core 3. At the same time, a circumferential groove 11 that is substantially perpendicular to the longitudinal groove is bored in the outer circumference 3A of the movable core 3, and a guide ball that contacts the inner surface of the guide cylinder 1 is provided in the intersecting groove 12 between the longitudinal groove 10 and the circumferential groove 11. A movable iron core in an electromagnetic actuator in which 13 are arranged. 2. The movable core for an electromagnetic actuator according to claim 1, wherein a plurality of said longitudinal grooves are provided at equal intervals on the outer circumference 3A of the movable core. Claim 1, wherein a plurality of said circumferential grooves 11 are provided.
A movable iron core in the electromagnetic actuator described in . The groove width a of the vertical groove 10 is the diameter d of the guide ball 13.
The movable core in an electromagnetic actuator according to claim 1, wherein d sin45°<a<d. 2. The movable core for an electromagnetic actuator according to claim 1, wherein the groove width b of the circumferential groove 11 in relation to the diameter d of the guide ball 13 satisfies d sin45°<b<d. 2. The movable core for an electromagnetic actuator according to claim 1, wherein the vertical grooves 10 in the movable core 3 are formed of drawn material.