JPH01158279A - Steel ball electromagnet - Google Patents

Abstract

PURPOSE:To stabilize valve motion by providing uniform gap between a steel ball and a magnetic plate thereby attracting the steel ball uniformly to the inner diameter face of the magnetic plate. CONSTITUTION:A steel ball 5 is attracted to the side of a magnetic plate 6 when power is fed to an exciting coil wound around a bobbin 8. Several protrusions 10 are provided at the side of the bobbin 8 contacting with the magnetic plate 6. Since uniform gap can be provided between the steel ball 5 and the magnetic plate 6 by means of the protrusions 10, the steel ball 5 is attracted uniformly to the inner diameter face of the magnetic plate 6.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a hydraulic switching solenoid valve for an automatic transmission for an automobile.
In particular, it relates to a structure that is inexpensive and has a stable suction force.

[Conventional technology]

The prior art, as described in Registration No. 938905, had a structure in which the steel balls were located inside a magnetic plate.

[Problem that the invention seeks to solve]

In the above-mentioned conventional technology, no consideration was given to the steel ball receiver, and there was a problem in that the outer diameter of the steel ball came into contact with the magnetic plate when the coil was energized, resulting in unstable operation. An object of the present invention is to always keep the gap between the outer diameter of the steel ball and the inner diameter of the magnetic plate constant under any circumstances.

[Means for solving problems]

The above object is achieved by providing three protrusions on a resin coil bobbin to receive the steel ball at the center so that it does not come into contact with the magnetic plate under any circumstances.

[Effect]

The steel balls are placed in three protrusions on the resin bobbin, making them stable in the radial direction. By providing the magnetic plate with an inner diameter slightly larger than the inner diameter of the protrusions, the steel balls always remain in contact with the magnetic plate. Since the gap can be kept constant, the suction force can be increased and the characteristics are more stable.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. Reference numeral 1 denotes a torque converter section for an automobile, and an electromagnet 2 for switching oil pressure is attached thereto, and the electromagnet 2 responds to an external signal. 3 is a yoke that forms a magnetic circuit and integrates a fixed valve portion 4. The steel ball 5 corresponds to the fixed valve part 4. The magnetic plate 6 forms a magnetic circuit together with the yoke 3. The stopper 7 prevents the steel ball 5 from being positioned and removed.

Reference numeral 8 denotes a bobbin made of an insulator, around which an excitation coil 9 is wound. Further, the bobbin 8 has a convex portion 10 divided into three equal parts.
is provided, and the relationship between the inner diameter φdl of the convex portion 10 and the outer diameter φD of the steel ball is φdx>φD. 1
1 is a hole into which the protruding portion 10 is inserted, and its diameter φdZ is φd1 and φd2.

It has the configuration and shape as described above, and its operation is as follows. When the excitation coil 9 is energized by an external signal, the steel ball 5 moves to the left by electromagnetic force and is simultaneously attracted to the inner diameter surface of the magnetic plate 6, but the radial movement of the steel ball 5 is caused by the bobbin. The inner diameter φd of the convex portion 10 of 8
Since it is defined by 1, it is almost uniformly attracted to the inner diameter surface of the magnetic plate 6. Therefore, the force of the steel ball 5 attracted to the inner diameter surface of the magnetic plate 6 can be ignored. Further, the protrusion 10 may be polygonal, but in order to reduce the sliding resistance with the steel ball 5, a cylinder is preferable.

〔Effect of the invention〕

According to the present invention, the gap between the steel ball 5 and the magnetic plate 6 can be easily equalized by the three protrusions 10 provided on the resin bobbin 8, so that the steel ball 5 is evenly spaced on the inner diameter surface of the magnetic plate 6. steel ball 5 because it is attracted to
effectively moves to the left and closes the valve. Therefore, there are effects such as stable operation.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of one embodiment of the present invention, and FIG. 2 is a detailed perspective view of the present invention.

Claims (1)

[Claims] 1. In the electromagnet, which has a structure in which a fixed valve and a corresponding steel ball are arranged, and the steel ball is moved by an electromagnet to close the valve, several protrusions are formed on the resin bobbin around which the coil is wound, on the side where it contacts the magnetic plate. A steel ball electromagnet characterized in that a steel ball is arranged on the inner diameter of the protrusion.