JPH04221810A - Mobile core for solenoid and surface treatment method therefore - Google Patents

Abstract

PURPOSE:To suppress the friction of the title mobile core with a guide member so as to prolong the service life of the core by increasing the surface roughness of the core by subjecting the core to a lapping process after the surface hardness of the core is increased by a nitriding process. CONSTITUTION:The surface hardness of a machined mobile core 1 is increased by nitriding (tufftriding) the surface of the core l. After nitriding the core 1, the core 1 is subjected to barrel processing to remove scales produced during the course of the nitriding process. After the barrel processing, the core 1 is subjected to a lapping process. By appropriately selecting the capacity of the used barrel, chip, barrel liquid, barrel processing time, and number of processing times, the surface roughness of the core 1 is increased to a prescribed value. After the core 1 is subjected to the above-mentioned processes, the core 1 is incorporated in a solenoid main body using a resin-made coil bobbin 3 as a guide member.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid used in pachinko and the like.

0002

2. Description of the Related Art FIG. 12 shows a conventional movable iron core 1', and the conventional surface treatment of this movable iron core 1' was performed as follows. That is, first, the surface of the cut movable iron core 1' is plated with copper under nickel for rust prevention, and then,
This is a method of coating with a material with good sliding properties, such as fluororesin or molybdenum disulfide.

0003

[Problems to be Solved by the Invention] In this case, since it is a coating, as shown in FIG. Areas where there is contact (X, Y areas in Figure 13) will peel off early, and once peeled off, the rough surface of the base will be exposed, causing friction and wear between the movable core 1' and the guide material 2. There was a problem that the number of people was increasing rapidly.

The present invention has been provided in view of the above-mentioned points, and after the surface hardness is increased by nitriding treatment, the surface roughness is increased by lapping treatment, thereby reducing the friction with the guide material. The purpose of this is to provide a solenoid with a long service life.

[0005]

[Means for Solving the Problems] The present invention provides a solenoid comprising a movable core that is attracted and driven by the excitation of a coil and is movably disposed within a guide material, and a fixed core that attracts the movable core. A taper is formed on the periphery of the tip of the iron core. In claim 2, in a solenoid comprising a movable core which is attracted and driven by the excitation of a coil and is movably disposed within a guide material, and a fixed core which attracts the movable core, the surface of the movable core after cutting is completed. After that, nitriding treatment is performed, barrel treatment is performed to remove scale, and then lapping treatment is performed.

[0006] Furthermore, in the third aspect of the present invention, an elastic spacer is provided on the tip end face of the movable core that collides with the fixed core.

[0007]

[Function] By eliminating the peripheral edge of the tip of the movable core and making it tapered, the wear of the guide material is reduced. In claim 2, the surface of the movable core after cutting is subjected to nitride treatment, barrel treatment is performed to remove scale, and then lapping treatment is performed to reduce wear on the surface of the movable core and the guide material. I'm letting you do it.

Furthermore, in claim 3, an elastic spacer is provided on the tip end face of the movable core to prevent deformation of the movable core and the fixed core.

[0009]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a cross-sectional view of a solenoid, and a coil bobbin 5 having a coil 4 wound around its outer periphery is disposed within a yoke 3 having a U-shaped cross section. Furthermore, a permanent magnet 6 is arranged at the end of the coil bobbin 1.

Fixed iron core 7 disposed within coil bobbin 5
One end of the movable iron core 1 is fixed to the yoke 3, and a recess 9 is formed in the other end into which the protrusion 8 at the tip of the movable iron core 1 is attracted and fitted. The movable iron core 1 is disposed within a coil bobbin 3 so as to be movable laterally, and in this embodiment, the coil bobbin 3 also serves as a guide member. Now, when the coil 4 is excited, the movable iron core 1 is attracted to the fixed iron core 7, and the protrusion 8 at the tip collides with and fits into the recess 9 of the fixed iron core 7. And coil 4
Even if the power supply to the movable iron core 1 is cut off, the state of the movable iron core 1 is maintained by the magnetic flux of the permanent magnet 6.

The movable iron core 1 is surface-treated as follows. That is, the surface of the movable iron core 1 that has been cut is subjected to a nitride treatment (tuftride treatment) to increase the surface hardness. After this treatment, barrel treatment is performed to remove scale by nitriding treatment. After this barrel treatment,
Perform wrapping processing. By appropriately selecting the barrel tank capacity, chips, barrel liquid, barrel time, and number of times used, the surface roughness can be raised to a predetermined value.

[0012] The material of the movable iron core 1 is a magnetic material,
Any material may be used as long as its hardness is improved to a predetermined value by nitriding treatment. In addition, the reason for performing nitriding treatment is that in the case of free-cutting steel, the surface hardness is low if it is left untreated, so the surface roughness will not improve even if lapping is performed, and it is also a rust prevention measure. It is. The movable iron core 1 subjected to the above treatment is assembled into a solenoid body using a resin coil bobbin 3 as a guide material.

FIG. 2 shows a metal guide pipe 10 arranged inside a coil bobbin 3, and a fixed iron core 7 inside the guide pipe 10.
A case is shown in which a movable iron core 1 is arranged and a guide pipe 10 is used as a guide material. In this way, by increasing the hardness of the surface of the movable iron core 1, the surface roughness can be reduced to 0.
6S, and therefore, it is possible to reduce wear on the inner surface of the coil bobbin 3 or guide materials such as the metal guide pipe 10, and the surface of the movable iron core 1, and it does not peel off unlike coatings. Therefore, the life of the solenoid can be extended.

Furthermore, since the nitride treatment and surface roughness have been improved, it will not rust in a normal environment, so there is no need for antirust measures such as plating treatment. [Embodiment 2] By the way, as shown in FIG.
Since the peripheral edge of the distal end portion of the movable iron core 1 is formed into an edge shape, the movable iron core 1 slides while the edge 11 scrapes the inner surface of the coil bobbin 5. This is because there is a clearance 12 between the movable iron core 1 and the guide material such as the coil bobbin 5. Therefore, as shown in part A of FIG. 3, wear occurs on the inner surface of the coil bobbin 5. In other words, in such a state, the guide material of the sliding portion comes into local contact and is likely to wear out.

Therefore, in this embodiment, as shown in FIGS. 4 and 5, a taper 13 is formed on the periphery of the distal end of the movable core 1 on the base side of the protrusion 8 to reduce wear with the guide material. are doing. The connecting portion between the surface of the taper 13 and the outer diameter surface is made into a smooth curved surface by lapping treatment to improve the surface roughness. Therefore, as shown in FIG.
The surface of the taper 13, which is the sliding part, slides on the guide material such as the coil bobbin 5 over a wider area than in the previous embodiment, and the guide material is not scraped by the edge. Note that this increases the surface hardness of the movable core 1 and reduces the surface roughness to 0.
．． It is particularly effective when processing is performed to improve it to about 4S.

[Embodiment 3] By the way, since the movable iron core 1 and the fixed iron core 7 are made of metal, if they collide with each other, the collision surface will be deformed. That is, as shown in FIG. 7, in the movable core 1, the area around the tip of the protrusion 8 is crushed (B
), if the crushing due to this deformation becomes severe, the fixed core 7
It comes into contact with the inner surface of the recess 9. Further, on the fixed iron core 7 side, a dent (C in the figure) is formed on the inner surface of the recess 9.

In such a case, the holding force characteristics may deteriorate, the magnetic leakage due to contact between the movable core 1 and the fixed core 7 during the stroke may cause a decrease in the attractive force, and an increase in the frictional force, making it impossible to use the product for a long period of time. It disappears. Further, as shown in FIG. 8, when a stopper 14 made of an elastic body is incorporated into the base of the movable iron core 1 via a presser metal fitting 15, an increase in size and number of parts are unavoidable.

Therefore, in this embodiment, as shown in FIGS. 9 and 10, a recess 16 is formed at the tip of the movable iron core 1.
A spacer 17 made of an elastic body and having a flat tip is disposed in this recess 16. The material of this spacer 17 is, for example, urethane, and the dimension A of the tip of the spacer 17 shown in FIG. 10 is determined in consideration of the required holding force, the moldability of the urethane material, and deterioration due to collision. Furthermore, the material of the spacer 17 is not limited to urethane;
Any material may be used as long as it satisfies moldability and the like.

FIG. 11 shows a spacer 17, which is attached to the movable core 1.
The fitting part 18 fitted into the recess 16 of the movable iron core 1
The flat part 19 is located at the distal end surface of the holder. Three ribs 20 are formed in the longitudinal direction around the rod-shaped fitting part 18, and by pressing these ribs 20 against the inner surface of the recess 16, the spacer 17 is fitted into the recess 16 of the movable iron core 1. That will happen.

In this embodiment, the spacer 17 is
By increasing or decreasing the A dimension of the flat portion 19, the value of the holding force of the movable iron core 1 can be changed to an arbitrary value. In addition, the number of parts is smaller than that in the case of FIG. 8, and the assembly work is easy because all that is required is to push the parts into the recess 16 of the movable iron core 1.

[0021]

Effects of the Invention As described above, the present invention provides a solenoid comprising a movable core that is attracted and driven by the excitation of a coil and is movably disposed within a guide material, and a fixed core that attracts the movable core. Since the tip of the iron core is tapered, the taper allows it to slide on the guide material over a wider area, and since there are no edges on the sliding part, wear on the guide material is reduced. It is possible to extend the life of the solenoid, and since only a part of the shape of the movable core is changed, the number of parts does not increase and machining is easy, so it has the effect of extending the life without increasing costs. It is.

[0022] According to a second aspect of the present invention, in a solenoid comprising a movable core which is attracted and driven by the excitation of a coil and is movably disposed within a guide material, and a fixed core which attracts the movable core, the movable core is Since the surface of the iron core is subjected to nitriding treatment, barrel treatment is performed to remove scale, and then lapping treatment is performed, it is possible to reduce wear on the surface of the movable iron core and the guide material. In addition, by nitriding the movable core, the surface hardness of the movable core can be increased and the surface roughness can be improved to about 0.6S. This reduces wear on the inner sliding parts of the solenoid and guide pipe, and also prevents the coating from peeling off, resulting in a longer life for the solenoid. In addition, since the movable iron core is treated with nitride and has improved surface roughness, it will not rust in normal environments, so there is no need for anti-rust measures such as plating.

In addition, in claim 3, by providing an elastic spacer on the end face of the movable core that collides with the fixed core, the collision between the movable core and the fixed core is performed via the elastic body. Deformation of the movable core and fixed core is prevented,
It is possible to maintain the initial characteristics over a long period of time, resulting in a long-life solenoid, and since the collision occurs via an elastic body, the collision noise is reduced.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a solenoid according to an embodiment of the present invention.

FIG. 2 is a sectional view of a solenoid in which the guide member is of a guide pipe type.

FIG. 3 is an operation explanatory diagram.

FIG. 4 is a side view of another embodiment of the movable core.

FIG. 5 is an enlarged side view of the main part of the movable iron core.

FIG. 6 is an operation explanatory diagram.

FIG. 7 is an operation explanatory diagram.

FIG. 8 is an explanatory diagram.

FIG. 9(a) is a plan view of still another embodiment of the movable core. (b) is a broken side view.

FIG. 10 is an enlarged cross-sectional view of the main part of the movable core.

FIG. 11(a) is a plan view of a spacer. (b) is a side view.

FIG. 12 is a side view of a conventional movable iron core.

FIG. 13 is an explanatory diagram of the operation of a conventional example.

[Explanation of symbols]

1. Movable iron core 7 Fixed core 13 Taper 17 Spacer

Claims (3)

[Claims] Claim 1: In a solenoid consisting of a movable core that is attracted and driven by the excitation of a coil and is movably disposed within a guide material, and a fixed core that attracts the movable core, the tip of the movable core is tapered. A movable iron core of a solenoid characterized by the following: 2. In a solenoid consisting of a movable core that is attracted and driven by the excitation of a coil and is movably disposed within a guide material, and a fixed core that attracts the movable core, the surface of the movable core that has been cut is A method for surface treatment of a movable core of a solenoid, characterized in that a nitride treatment is performed on the movable core of a solenoid, a barrel treatment is performed to remove scale, and a lapping treatment is performed. 3. Claim 1, characterized in that an elastic spacer is provided on the tip end surface of the movable core that collides with the fixed core.
Movable iron core of the solenoid described.