JPH07211544A - Electromagnetic actuator - Google Patents

Abstract

PURPOSE:To provide a low-cost electromagnetic actuator wherein accidents would hardly occur by forming a ring-shaped projection integrally with a resin- made coil bobbin on the inner face of the coil bobbin and letting it engage with a step formed on a plunger and preventing the plunger from crashing directly against a top yoke or a fixed yoke. CONSTITUTION:An exciting coil 7 wherein electric current is allowed to flow to drive a plunger l is wound around an electrically insulating resin-made coil bobbin 6. Integrally with the inner face of the coil bobbin 6 where the plunger 1 is driven, a ring-shaped projection 6a is formed so as to face a step la formed on the external face of an edge of the plunger 1. When the face of the ring- shaped projection 6a of the coil bobbin is abutted by the face of the step 1a of the plunger, a space of the proper size is formed between the face of the edge of the plunger and the face of a fixed yoke. By this method, an electromagnetic actuator which can be assembled easily and which would have few defects can be provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound deadening type electromagnetic actuator having a structure for reducing metallic collision noise generated when a plunger directly collides with a fixed yoke or a top yoke during operation of the electromagnetic actuator. Is.

[0002]

2. Description of the Related Art FIG. 8 is an external view of a conventional silencer type electromagnetic actuator, and FIG. 9 is a vertical sectional view showing the internal structure thereof.
Fig. 1 shows the plunger with E-ring and noise reduction ring attached.
It shows in 0. Depending on the direction of the direct current flowing through the exciting coil 7 (hereinafter referred to as coil), the magnetic flux generated by the permanent magnet 8 magnetized with the same polarity in the outer peripheral surface direction of the plunger 1 is driven by the magnetic field generated by the current flowing through the exciting coil. At the time of erasing, the plunger 1 is moved to the position of the chain double-dashed line in the left direction of FIG. 9 away from the fixed yoke 2 by the force of the spring (not shown) to move the connecting rod connected to the plunger and mechanically. When a displacement is applied and the direction of the current flowing through the exciting coil 7 is changed to make the magnetic flux produced by the permanent magnet 8 and the magnetic field produced by the exciting coil 7 in the same direction, the plunger 1 resists the force of the spring and moves in the direction of the fixed yoke 2. It moves rapidly and provides mechanical displacement to the other by a connecting rod that connects to the plunger. At this time, the plunger 1 collides with the fixed yoke 2 and the top yoke 4, and emits a highly metallic impact sound.

For this reason, as shown in FIGS. 8 to 10, a groove is provided in a part of the plunger, the E ring 9 is attached to the groove, and the top yoke between the top yoke 4 and the E ring fixed to the plunger. The sound deadening ring 3 made of rubber or resin is attached to the part that collides with 4, and a gap is formed between the plunger 1 and the fixed yoke 2, and when the plunger 1 is operated, the E ring and the E ring fixed to the plunger are used. The supported silencing ring was brought into contact with the top yoke to soften the collision of the plunger, and at the same time, the plunger and the fixed yoke were prevented from directly colliding with each other to muffle the sound. But,
If the ambient temperature becomes high in the environment of use, the rubber that forms the E-ring and the muffling ring will stick and cause malfunctions.
When the number of movements increases, the E-ring deforms and falls off,
There was an accident such as a shock noise.

Further, although the surface of the plunger is subjected to surface treatment for rust prevention, the surface-treated coating is peeled off when the E ring is attached to the plunger, and rust or the like is generated on the surface of the plunger. was there.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate these drawbacks, and to provide a noise-reduction type electromagnetic actuator which is inexpensive and does not cause an accident.

[0006]

SUMMARY OF THE INVENTION According to the present invention, a rubber or a soft resin is used without damaging a muffling ring when an electromagnetic actuator is used under a high ambient temperature condition or using an E ring which is damaged when it is repeatedly used. The sound absorbing ring is fixed to the top yoke or fixed yoke of the electromagnetic actuator to absorb the impact sound of the plunger colliding with the top yoke or fixed yoke, or to the inner circumference of the inner circumference of the soft resin coil bobbin. An annular protrusion is formed integrally with the coil bobbin on the surface to engage with the step provided on the plunger to prevent the plunger from directly colliding with the top yoke or the fixed yoke. Use an electromagnetic actuator with a configuration that is easy to operate.

According to the first embodiment of the present invention, the inner circumference of a resin coil bobbin around which an exciting coil is wound near the fixed yoke at the tip of the plunger is integrated with the coil bobbin that engages with the step at the tip of the plunger. An annular protrusion is provided, and on the other hand, an annular step is provided near the fixed yoke at the tip of the plunger and around the tip of the plunger.The plunger driven by the current flowing in the exciting coil is driven to the fixed yoke side, and the inner peripheral portion of the coil bobbin When the step of the plunger is engaged with the projection of, the gap is formed between the tip of the plunger and the fixed yoke in contact with the plunger to prevent the fixed yoke and the plunger from directly colliding with each other. As the material of the resin used for the coil bobbin, a soft and flexible resin such as nylon or polyester resin is used.

In the second embodiment according to the present invention, a muffler ring provided with a fitting groove on the outer circumference is formed so that the plunger on the front surface of the electromagnetic actuator fits to the inner circumferential end of the top yoke passing through the center. The inner peripheral edge of the top yoke is fitted and fixed in the fitting groove provided on the outer periphery, part of the noise reduction ring is projected to the front surface of the top yoke, and the outer circumferential surface on the plunger side contacts the noise reduction ring on the front surface of the top yoke. A step is provided, and when the silencer ring on the front surface of the top yoke and the step of the plunger are joined, a gap is formed between the tip of the plunger and the fixed yoke to prevent the plunger and the fixed yoke from directly colliding. To do.

In the third embodiment of the present invention, a sound deadening ring is attached to the abutting surface of the fixed yoke where the plunger and the fixed yoke collide with each other to prevent the plunger and the fixed yoke from directly colliding. Also, two or more of the first to third embodiments are combined and configured.

According to the present invention, an exterior yoke comprising a side yoke and a top yoke made of a soft magnetic material, and a resin disposed inside the exterior yoke, penetrating through the center of the top yoke of the exterior yoke, in the end face direction of the side yoke. Made of soft magnetic material that slides freely on the inner circumference of a coil bobbin made of steel, an exciting coil wound around the plunger around the coil bobbin, and a soft magnetic material provided between the tip of the plunger and the side yoke. In an electromagnetic actuator consisting of a fixed yoke of material, a coil bobbin having an annular protrusion on the inner peripheral surface of the inner diameter portion near the end where the plunger contacts the fixed yoke, and a coil bobbin at the tip facing the fixed yoke of the plunger. Of the plunger, which is in contact with the protrusion on the inner peripheral surface of the plunger and which has a step between the tip of the plunger and the fixed yoke. It is the electromagnetic actuator, wherein the.

According to the present invention, an exterior yoke composed of a side yoke and a top yoke made of a soft magnetic material, and a resin which penetrates the center of the top yoke of the exterior yoke and is disposed inside the exterior yoke in the end face direction of the side yoke. Made of a soft magnetic material that slides freely on the inner circumference of a coil bobbin made of steel, an exciting coil wound around the plunger around the coil bobbin, and a soft magnetic material provided between the tip of the plunger and the side yoke. In an electromagnetic actuator consisting of a fixed yoke of a material, a silencer ring fixed to the top yoke by an inner peripheral surface of the top yoke through which the plunger penetrates and a fitting groove protruding to the front surface of the top yoke and having an outer periphery fitted to the top yoke. A plunger provided on the outer peripheral surface thereof with a step portion that is in contact with the noise reduction ring and forms a gap between the fixed yoke and the tip of the plunger It is composed of an electromagnetic actuator according to claim.

According to the present invention, an exterior yoke composed of a side yoke and a top yoke made of a soft magnetic material, and a resin disposed inside the exterior yoke, penetrating through the center of the top yoke of the exterior yoke, in the end face direction of the side yoke. Made of a soft magnetic material that slides freely on the inner circumference of a coil bobbin made of steel, an exciting coil wound around the plunger around the coil bobbin, and a soft magnetic material provided between the tip of the plunger and the side yoke. In an electromagnetic actuator consisting of a fixed yoke of a material, the fixed yoke is fixed to the surface facing the plunger, the outer peripheral surface covers the joint surface with the plunger, and the inner peripheral surface has the same taper angle as the taper angle of the plunger tip. The ring-shaped sound deadening ring and the outer peripheral surface facing the sound deadening ring are in close contact with the sound deadening ring, and a gap is formed between the fixed yoke and the tip of the plunger. An electromagnetic actuator, characterized in that comprising a plunger provided with a step to.

The present invention is an electromagnetic actuator comprising a combination of the electromagnetic actuator according to the above paragraph and the electromagnetic actuator according to the above paragraph.

[0014]

[Function] The sound deadening ring mounted and fixed on the inner peripheral edge of the top yoke by the fitting groove on the front surface of the top yoke abuts on the stepped portion provided on the outer peripheral surface of the plunger, and when driving the plunger, the sound deadening ring is provided between the plunger and the fixed yoke. A void is formed in the structure to prevent a direct collision, and at the same time, the impact at the time of collision is absorbed by a rubber or resin sound deadening ring attached to the front surface of the top yoke.

The sound deadening ring fixedly attached to the surface of the fixed yoke that contacts the plunger prevents a direct collision by forming a gap between the tip of the plunger and the fixed yoke when the plunger is driven. Alternatively, the sound deadening ring made of resin absorbs the impact when the plunger and the fixed yoke collide.

When an annular projection provided on the inner peripheral surface on which the plunger of the coil bobbin winding the exciting coil for supplying a drive current for driving the plunger slides, and a step formed on the outer periphery of the tip of the plunger are brought into contact with each other. A gap is formed between the fixed yoke and the tip of the plunger to prevent generation of impact noise due to direct collision between the plunger and the fixed yoke when the plunger is driven. Further, by using a soft resin material for the coil bobbin, the impact sound generated when the plunger collides with the annular protrusion of the coil bobbin is absorbed. With the above configuration, the E-ring is not used, so there is no risk of scratches or rust on the plunger.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of an electromagnetic actuator according to the present invention will be described with reference to the drawings. 1 is an external perspective view of a first embodiment of the present invention, FIG. 2 is a longitudinal sectional view of the electromagnetic actuator shown in FIG. 1, and FIG. 3 is an enlarged view of a portion shown in A of FIG. In the electromagnetic actuator of the present invention, the plunger 1 of the resin coil bobbin 6 made of an electrically insulating material for winding the exciting coil 7 that conducts the current for driving the plunger 1 slides integrally with the inner peripheral surface of the plunger 1. An annular protrusion 6a is provided so as to face a step provided on the outer peripheral surface of the tip of the No. 1. On the other hand, at the tip portion of the plunger 1, a step 1a is formed around the outer peripheral surface of the plunger, and when the surface of the step 1a of the plunger comes into contact with the surface of the annular protrusion 6a of the coil bobbin, it is fixed to the surface of the tip of the plunger. By forming an appropriate gap between the surfaces of the yoke, direct collision between the plunger tip and the fixed yoke is prevented. On the other hand, since the coil bobbin is made of a soft resin such as nylon, polyester, or polyethylene terephthalate, even if the step 1a of the plunger 1 collides with the projection 6a of the coil bobbin 6 when the plunger is driven, most of the shock is generated. It is absorbed by and does not produce a loud sound.

FIG. 4 shows a longitudinal sectional view of an electromagnetic actuator showing a second embodiment of the present invention, and FIG. 5 shows B shown in FIG.
The portion of is shown enlarged. In the present invention, the sound deadening ring 3a made of rubber or soft resin is fitted to the outer circumference on the inner circumference side end surface of the through hole through which the plunger 1 in the center of the top yoke 4 of the soft magnetic material on the front surface of the electromagnetic actuator passes. A sound deadening ring 3a having a mating groove 31 is fitted to allow a part of the sound deadening ring 3a to project from the front surface of the top yoke, while the sound deadening ring 3 is attached to the front surface of the top yoke on the outer peripheral surface of the plunger.
A step portion 1b that abuts a is formed on the entire circumference of the plunger 1, and a gap is formed so that the tip of the plunger 1 and the fixed yoke 2 do not collide with each other when abutting on the sound deadening ring 3a. With this configuration, when the plunger is driven, the step portion 1b on the outer periphery of the plunger abuts on the front surface of the sound deadening ring 3a on the front surface of the top yoke 4, so that the plunger and the fixed yoke do not directly collide, and The top yoke noise reduction ring 3a absorbs the impact of the plunger 1 and reduces the collision noise.

FIG. 6 is a vertical sectional view showing a third embodiment of the electromagnetic actuator according to the present invention, and FIG. 7 is an enlarged view of a portion C of FIG. In the present invention, the outer peripheral surface made of rubber or soft resin is in close contact with the inner peripheral surface of the fixed yoke, and the inner peripheral surface has the annular silencer ring 3b having the same taper angle as the distal end of the plunger. Is fixed to the contacting portion of the plunger, and when the tip of the plunger comes into contact with the sound deadening ring 3b, a gap is provided between the tip of the plunger and the fixed yoke. The structure is such that the tip of the plunger 1 does not directly contact. When the plunger collides with the fixed yoke, the sound deadening ring 3b provided between the plunger and the fixed yoke in close contact with the fixed yoke absorbs the impact at the time of the collision between the plunger 1 and the fixed yoke 2, and the plunger operates. Reduces the sound when you do.

In the electromagnetic actuator of the present invention, it goes without saying that the first to third embodiments described above may be combined with each other to form a silenced electromagnetic actuator.

[0021]

Since the electromagnetic actuator of the present invention does not use the E-ring that has been conventionally used, the plunger is not scratched or rusted, and the inner peripheral surface of the coil bobbin made of soft resin is not used. The structure having the ring-shaped silencing ring formed integrally with the ring-shaped projection does not require a step of assembling the E-ring and the silencing ring, and has an effect that the assembly is easy and an electromagnetic actuator with few defects is provided.

[Brief description of drawings]

FIG. 1 is an external perspective view of a first embodiment according to the present invention.

FIG. 2 is a longitudinal sectional view of the first embodiment according to the present invention.

FIG. 3 is a partially enlarged view of a portion A of FIG.

FIG. 4 is a vertical sectional view of a second embodiment according to the present invention.

FIG. 5 is a partially enlarged view of portion B of FIG.

FIG. 6 is a vertical sectional view of a third embodiment according to the present invention.

7 is a partially enlarged view of a portion C of FIG.

FIG. 8 is an external perspective view of a conventional example.

9 is a vertical cross-sectional view of the conventional example shown in FIG.

10 is an external perspective view of the conventional plunger shown in FIG.

[Explanation of symbols]

 1 Plunger 1a, 1c Step 1b Step 2 Fixed yoke 3 Noise reduction ring 3a, 3b Noise reduction ring 4 Top yoke 5 Side yoke 6 Coil bobbin 6a Protrusion 7 Excitation coil 8 Permanent magnet 9 E ring 10 Connection rod insertion hole 31 Fitting groove

Claims (4)

[Claims] 1. An exterior yoke comprising a side yoke and a top yoke made of a soft magnetic material, and a resin made inside the exterior yoke that penetrates through the center of the top yoke of the exterior yoke and is arranged inside the exterior yoke in the end face direction of the side yoke. A plunger of a soft magnetic material that freely slides on the inner peripheral portion of the coil bobbin, an exciting coil wound around the coil bobbin around the plunger, and a soft magnetic material provided between the tip of the plunger and the side yoke. In an electromagnetic actuator consisting of a fixed yoke,
A coil bobbin provided with an annular protrusion on the inner peripheral surface in the vicinity of the plunger abutting the end of the fixed yoke, and a tip of the plunger facing the fixed yoke, abutting the protrusion on the inner peripheral surface of the coil bobbin, and An electromagnetic actuator comprising: a plunger provided with a step forming an air gap between a tip and a fixed yoke. 2. An exterior yoke composed of a side yoke and a top yoke made of a soft magnetic material, and a resin made of a resin which penetrates through the center of the top yoke of the exterior yoke and is disposed inside the exterior yoke in the end face direction of the side yoke. A plunger of a soft magnetic material that freely slides on the inner peripheral portion of the coil bobbin, an exciting coil wound around the coil bobbin around the plunger, and a soft magnetic material provided between the tip of the plunger and the side yoke. In an electromagnetic actuator consisting of a fixed yoke,
A sound deadening ring fixed to the top yoke by a fitting groove that protrudes from the inner peripheral surface of the top yoke through which the plunger penetrates and the front surface of the top yoke and has an outer circumference fitted to the top yoke; and a sound deadening ring that abuts the sound deadening ring on the outer peripheral surface. An electromagnetic actuator comprising: a fixed yoke and a plunger having a stepped portion that forms a gap between the tip of the plunger and the plunger. 3. An exterior yoke comprising a side yoke and a top yoke made of a soft magnetic material, and a resin-made yoke which penetrates through the center of the top yoke of the exterior yoke and is arranged inside the exterior yoke in the end face direction of the side yoke. A plunger of a soft magnetic material that freely slides on the inner peripheral portion of the coil bobbin, an exciting coil wound around the coil bobbin around the plunger, and a soft magnetic material provided between the tip of the plunger and the side yoke. In an electromagnetic actuator consisting of a fixed yoke,
An annular silencer ring fixed to the surface of the fixed yoke facing the plunger, the outer peripheral surface covering the joint surface with the plunger, and the inner peripheral surface having the same taper angle as the tip angle of the plunger, and the sound absorbing ring facing the silencer ring. An electromagnetic actuator characterized in that the outer peripheral surface of the plunger is in close contact with the sound deadening ring, and the plunger is provided with a step forming a gap between the fixed yoke and the tip of the plunger. 4. An electromagnetic actuator comprising a combination of the electromagnetic actuator according to claim 1 and the electromagnetic actuator according to claim 2.