JPS59177904A - Solenoid - Google Patents

Abstract

PURPOSE:To improve the attractive force characteristics to the traveling stroke of a plunger by a method wherein the surface of the plunger and the surface of a fixed core which are facing each other formed into spiral shape. CONSTITUTION:A plunger 3 is composed of magnetic material and inserted into a penetrating hole 2c of a coil frame 2a and can be moved freely. One end 3a of the plunger 3 is facing a fixed core and works as a contact surface of the movable side and is so formed as to be projected from the surface perpendicular to the plunger axis. Another end 3b of the plunger is connected to an outside load. The fixed core is composed of magnetic material and provided in the penetrating hole 2c of an exciting coil 2b. One end 4a of the fixed core is fixed to a yoke 1 and another end 4b works as a contact surface of the fixed side and is facing the spiral contact surface of the plunger 3 and is abutted against the plunger 3 by the excitation of the coil 2b. The shape of the contact surface of the fixed core is concave spiral corresponding to the spiral shape of the plunger 3.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a magnetic circuit consisting of a yoke, a plunger, and a coil.By energizing the coil, the plunger is reciprocated horizontally or vertically, thereby applying a driving force to an external load. Regarding the solenoid that transmits.

[Background technology]

In general, the attractive force characteristics of a solenoid are determined by the magnetic circuit cross-sectional area and coil winding specifications.
, (C), Machi, As shown in (e), the shape of the armature surface between the plunger and the fixed iron core is designed to increase the area of the opposing magnetic pole, or the armature is set at the maximum stroke position. Shorten the facing distance between the surfaces (StH stroke, l in the figure)
: facing distance), or measures were taken to reduce magnetic resistance and magnetic leakage in the magnetic circuit. However, a solenoid with a large initial suction force and a substantially constant suction force over the entire stroke has not been available, especially in the case of a long-stroke solenoid, and this has been a technical problem in the industry.

〔the purpose〕

The present invention has been made in view of the above points, that is, in a solenoid in which a plunger moves horizontally when a voltage is applied, the facing surfaces of the plunger and a fixed iron core facing each other are formed in a spiral shape. The purpose is to improve the suction force characteristics with respect to the moving stroke of the plunger.

[Disclosure of the invention]

(Example) The first embodiment of the present invention will be explained based on FIG. 2 (3) The yoke 1 has a rectangular cross section and is made of a magnetic material.

Reference numeral 2 denotes an excitation coil, and a through hole 2C is provided in the coil frame 2a through which the coil 2 is inserted. A plunger 3 is made of a magnetic material and is movably pushed into the through hole 2C of the coil frame 2a.One end 3a faces a fixed core (to be described later) and serves as a movable polarization surface, and its end surface shape is as follows. 6 As shown in Figure 6, the plunger has a spiral shape that protrudes from the vertical plane of the plunger shaft as far as the center line on the optical axis, and the other end 6b of the plunger is a connection part to an external load (not shown). be. A fixed iron core 4 is made of a magnetic material and is disposed in the through hole 2C of the excitation coil 2b, and one end 4a is fixed to the outer yoke 1, the other end 4b is an armature surface on the fixed side, and the plunger The spiral portion 6 comes into contact with the armature surface b, and therefore the shape of this armature surface forms a concave spiral shape corresponding to the butterfly line shape of the plunger 6, as shown in FIG. ing.

With this configuration, the stroke-suction (4) attractive force characteristics of this solenoid are improved as compared to the conventional example, as shown in FIG. That is, at the maximum stroke, the area of the opposing magnetic poles becomes larger, so that the attractive force becomes larger.

In the figure, A is the suction force characteristic of this embodiment, B is the suction force characteristic of the conventional example (b), and C is the suction force characteristic of the conventional example (C). As shown in FIG. 2, in the spiral armature surfaces of the fixed iron core 4 and the plunger 6, the opposing surfaces in the vertical direction on both axes are inclined at a predetermined angle in the same direction, and the both inclined surfaces 3c , 4c, the magnetic pole facing area becomes larger than that of the first embodiment, and the attractive force at the maximum stroke can be further increased.

Next, in the third embodiment, the spiral contact surface between the fixed iron core 4 and the plunger 3 is
By changing the spiral pitch XY of the plunger 6 from coarse to fine or from fine to coarse as shown in FIG. As shown by D in FIG. 4, the suction force at the maximum stroke can be made even larger than the characteristic A of the first embodiment.

Next, in the fourth embodiment, in the spiral polarization surface between the fixed iron core 4 and the plunger 6 shown in FIG.
When the plunger 3 is rotated by a predetermined angle in one direction P with respect to the helical direction around the axis of , and faces the fixed iron core, the plunger 3 is configured to only partially come into close contact with its armature surface during suction, and the suction force Therefore, as shown as the E characteristic in FIG. 4, a substantially uniform multiplicity characteristic is obtained over the entire stroke.

〔effect〕

As described above, the present invention comprises an excitation coil in a yoke having a rectangular cross section, and a fixed iron core having one end fixed to the yoke and the other end being an armature, and one end connected in the T through hole of the excitation coil. In a solenoid configured with a movable plunger whose other end is connected to an external load, the fixed iron core and the plunger's arming surfaces are each spiral-shaped, which is different from the conventional method described above. Compared to the case where the armature surface was flat or circular, the opposing area between the fixed iron core and the plunger's armature surfaces has increased, and the suction force at the maximum stroke has become thicker. Therefore, there is an effect that approximately uniform load characteristics can be obtained over the entire stroke.

, FIG. 2 is a longitudinal cross-sectional view of one embodiment of the lenoid of the present invention,
FIG. 6 is a cross-sectional view of the main part thereof, FIG. 4 is a suction force characteristic diagram of the unexploded protector, and FIG. 5 is a cross-sectional view of the main part of another embodiment.

1=yoke, 2=excitation coil, 6=plunger, 4=
Fixed core, 3a, 4b = spiral armature surface, 3C≠4c = inclined surface, X, Y = spiral pitch.

patent applicant Matsushita Electric Works Co., Ltd. Representative Patent Attorney Toshimaru Takemoto (2 others) (7) 17- 18-

Claims (4)

[Claims] (1) A yoke with a rectangular cross section, an excitation coil located inside the yoke and having a through hole in the center, and a plunger that is movably inserted into the through hole of the excitation coil and has one end as an armature surface. , in a solenoid comprising a fixed iron core located in the through hole of the excitation coil, one end of which is fixed to the yoke, and the other end coaxially opposed to the armature surface of the plunger, the fixed iron core and the plunger A solenoid characterized in that the contacting surfaces of the solenoid and the contact surface of the solenoid are each formed into a spiral shape. (2) In the spiral armature surfaces of the fixed core and the plunger, the vertical armature surfaces on both axes are inclined at a predetermined angle in the same direction. The solenoid described in item 1. (3) The solenoid according to claim 1, wherein the fixed core and the plunger face each other at different spiral pitches on the helical contact surfaces. (4) The spiral polarization surface between the fixed core and the plunger is rotated by a predetermined angle about the axis of the plunger to face the fixed core. The solenoid according to item 1, item 2, and item 3.