JP4548474B2 - Electromagnetic switch - Google Patents

Description

  The present invention relates to an electromagnetic switch for opening and closing an electrical contact provided in a motor circuit of a starter, for example.

As a prior art, an electromagnetic switch described in Patent Document 1 is known.
This electromagnetic switch includes an electromagnetic coil that forms an electromagnet when energized, a fixed iron core that is magnetized by the electromagnet, a plunger that is attracted to the magnetized fixed iron core, and the starter motor in conjunction with the movement of the plunger. It has a function of opening and closing a main contact provided in the circuit.
The fixed iron core used for this electromagnetic switch is divided into a core part 100 and a disk part 110 as shown in FIG. The core part 100 is integrally provided with a base part 101 disposed so as to face a plunger (not shown) and a boss part 102 protruding from the base part 101 in the anti-plunger direction (upward direction in the figure). On the other hand, the disk part 110 is configured by laminating a plurality of thin plates 111 each having a round hole formed in the center, and the round holes of the thin plates 111 communicate with each other to form a through hole 112. The core part 100 and the disk part 110 are fixed by press-fitting the boss part 102 into the inner periphery of the through hole 112.
JP-T-2002-524826

  However, in the related art described in Patent Document 1, for example, when the number of times of operation of the electromagnetic switch is extremely large, the boss portion 102 may come off from the through hole 112. That is, for each thin plate 111 constituting the disk unit 110, for example, when punching a round hole with a press, the inner diameter dimension of the round hole varies for each thin plate 111, the shape of the round hole is not a perfect circle, It may be slightly distorted. Alternatively, the shear surface when the round hole is punched with a press may be small (the plane in the press direction is insufficient).

Due to these factors, when the press-fitting load of the boss portion 102 to be press-fitted into the through-hole 112 is insufficient, the return force that acts on the plunger in a state where the plunger is adsorbed to the base portion 101 (the drive spring incorporated in the plunger The reaction force) may cause the boss portion 102 to come out of the round hole of the disk portion 110.
The present invention has been made based on the above circumstances, and an object of the present invention is to provide an electromagnetic switch that can ensure stable holding of the core portion without the boss portion of the core portion coming out of the through hole of the disk portion. It is in.

(Invention of Claim 1 )
The present invention includes an electromagnetic coil that forms an electromagnet when energized, a fixed iron core that is magnetized by the electromagnet, and a movable iron core that is attracted to the magnetized fixed iron core. An electromagnetic switch that opens and closes, and the fixed iron core is configured by stacking a plurality of thin plates each having a round hole formed in the central portion in the radial direction, and the round holes of each thin plate communicate with each other in the plate thickness direction. And a core portion having a base portion with one end surface in the axial direction facing the movable iron core and a boss portion protruding in the anti-movable iron core direction from the other end surface of the base portion .
When the thin plate disposed in the outermost layer on the side opposite to the base in the axial direction is called an end thin plate among a plurality of thin plates constituting the disk portion, the end thin plate is directed from one end side to the other end side in the plate thickness direction. By punching out the round hole with a press, a “press droop” is formed at the inner peripheral corner of the round hole opened on one end side in the plate thickness direction, and one end side of the end thin plate on which the “press droop” is formed is are arranged in the axial direction counter base portion side of the disk portion, the core portion, together with the assembled to the disc portion fitted a ball scan portion in the through hole of the disk portion, the axial end of the boss portion, A caulking portion is provided on a part or the entire periphery of the outer peripheral portion adjacent to the inner periphery of the through-hole, and the caulking portion is caulked in a state where the caulking portion rides on the “press droop”.

  According to the above configuration, since the caulking portion rides on the “press droop”, it is possible to prevent the boss portion from coming out of the through hole regardless of the quality of each thin plate used in the disc portion. That is, even when the inner diameter dimension of the round hole formed in the thin plate varies, the round hole shape is not a perfect circle, it is formed in a slightly distorted shape, or even when the shear surface of the round hole by the press is insufficient The core part can be held in a stable state with respect to the disk part. As a result, even when the number of operation times of the electromagnetic switch is extremely large, the boss portion does not come out of the through hole due to the return force acting on the movable core while the movable iron core is attracted to the base portion, and the stable core portion Therefore, it is possible to provide a highly reliable electromagnetic switch.

(Invention of Claim 2 )
The present invention includes an electromagnetic coil that forms an electromagnet when energized, a fixed iron core that is magnetized by the electromagnet, and a movable iron core that is attracted to the magnetized fixed iron core. An electromagnetic switch that opens and closes, and the fixed iron core is configured by stacking a plurality of thin plates each having a round hole formed in the central portion in the radial direction, and the round holes of each thin plate communicate with each other in the plate thickness direction. And a core portion having a base portion with one end surface in the axial direction facing the movable iron core and a boss portion protruding in the anti-movable iron core direction from the other end surface of the base portion .
When the thin plate arranged in the outermost layer on the side opposite to the base in the axial direction is called an end thin plate among the plurality of thin plates constituting the disk portion, this end thin plate is a round hole opening on one end side in the plate thickness direction. "chamfering" is formed on the inner peripheral corner portion, and one end of the end sheet that "chamfering" is formed is disposed toward the axial reaction base portion side of the disk portion, the core portion, disk volume scan unit fitted into the through-hole parts together are assembled to the disk portion, the axial end of the boss portion, the caulking portion is provided partially or on the entire circumference of the outer peripheral portion close to the inner periphery of the through hole, the The caulking portion is caulked in a state of being “chamfered”.

  According to the above configuration, since the caulking portion rides on “chamfering”, it is possible to prevent the boss portion from coming out of the through hole regardless of the quality of each thin plate used for the disc portion. That is, even when the inner diameter dimension of the round hole formed in the thin plate varies, the round hole shape is not a perfect circle, it is formed in a slightly distorted shape, or even when the shear surface of the round hole by the press is insufficient The core part can be held in a stable state with respect to the disk part. As a result, even when the number of operation times of the electromagnetic switch is extremely large, the boss portion does not come out of the through hole due to the return force acting on the movable core while the movable iron core is attracted to the base portion, and the stable core portion Therefore, it is possible to provide a highly reliable electromagnetic switch.

  The best mode for carrying out the present invention will be described in detail by the following examples.

1A is a plan view of the fixed core, FIG. 1B is a cross-sectional view of the fixed core, and FIG. 5 is a cross-sectional view of the electromagnetic switch 1.
The electromagnetic switch 1 of this embodiment has a function of opening and closing a main contact (described later) provided in the motor circuit of the starter, and as shown in FIG. 5, a contact to which two terminal bolts 2 and 3 are fixed. A cover 4, a set of fixed contacts 5 connected to the motor circuit via two terminal bolts 2 and 3, a movable contact 6 that intermittently connects the set of fixed contacts 5, and the movable contact 6 It is comprised from the solenoid (it demonstrates below) etc. which drive.
The solenoid includes an electromagnetic coil 7 that forms an electromagnet when energized, a fixed iron core 8 that is magnetized by the electromagnet, a plunger 10 that is inserted into the inner periphery of the electromagnetic coil 7 via a sleeve 9, a fixed iron core 8, and a plunger 10. The return spring 11 is disposed between the plunger rod 12 and the movable rod 6.

The electromagnetic coil 7 includes a suction coil 7a and a holding coil 7b wound around the bobbin 13 in a two-layer state, and is housed in a solenoid case 14 that forms a part of the magnetic circuit.
The fixed iron core 8 is divided into a core portion 80 disposed on the inner periphery of the sleeve 9 so as to face the plunger 10 and a disk portion 81 that holds the core portion 80, and is formed on the inner periphery of the solenoid case 14. The outer diameter portion of the disk portion 81 is in contact with the formed step and is positioned.
The plunger 10 is urged in the anti-core portion direction (left direction in FIG. 5) by the return spring 11, and a predetermined air gap is secured between the plunger 10 and the core portion 80 when the electromagnetic coil 7 is not energized.

One end of the plunger rod 12 is fixed to the end surface of the plunger 10 and is movable integrally with the plunger 10. The other end of the plunger rod 12 passes through a center hole formed in the core portion 80 of the fixed iron core 8 and enters a contact chamber 15 formed inside the contact cover 4.
The contact cover 4 is made of resin, is disposed with the rubber packing 16 between the disk portion 81 of the fixed iron core 8, and is fixed by caulking to the end of the solenoid case 14.
The two terminal bolts 2 and 3 are connected via a B terminal bolt 2 connected to the high potential side (battery side) of the motor circuit via a battery cable (not shown) and a motor lead wire (not shown). The M terminal bolt 3 is connected to the low potential side (motor side) of the motor circuit, and the fixed contact 5 is provided integrally with the bolt head disposed inside the contact cover 4.

The movable contact 6 is supported by an end of the plunger rod 12 that has entered the contact chamber 15 via an insulating member 17, and a contact pressure spring 18 disposed on the outer periphery of the plunger rod 12 in the distal direction of the plunger rod 12 ( The plunger rod 12 is prevented from coming off by a washer 19 urged in the right direction in FIG. 5 and caulked and fixed to the tip of the plunger rod 12.
The main contact is formed by a movable contact 6 and a set of fixed contacts 5. The movable contact 6 is brought into a closed state when the movable contact 6 abuts on the set of fixed contacts 5 and the fixed contacts 5 are electrically connected. Is separated from the two fixed contacts 5 and the continuity between the two fixed contacts 5 is cut off, thereby opening.

Then, the structure of the fixed iron core 8 which concerns on this invention is explained in full detail.
The fixed iron core 8 is divided into the core part 80 and the disk part 81 as described above.
The disk portion 81 is fixed by caulking and fixing a plurality of thin plates 82 having the same shape.
As shown in FIG. 3A, the thin plate 82 has a circular outer periphery, and has a ring shape in which a circular hole 82a is punched out at the center in the radial direction. FIG. 3B is a cross-sectional view of the thin plate 82 cut in the radial direction.
As shown in FIG. 1A, the disk portion 81 has a through hole 81a formed by communicating round holes 82a of each thin plate 82 in the plate thickness direction, and an end portion of the electromagnetic coil 7 as a disk portion. Two elongated holes 81b are formed in order to be drawn out to the opposite coil side of 81 (the right side of the disk portion 81 shown in FIG. 1B).

The core portion 80 is provided with a base portion 80a in which one end surface in the axial direction is arranged to face the plunger 10, and a boss portion 80b protruding in the anti-plunger direction from the other end surface of the base portion 80a. After the boss portion 80b is press-fitted into the through hole 81a of the disk portion 81 and assembled to the disk portion 81, the core portion 80 is further crimped to the disk portion 81 by crimping the outer peripheral portion of the axial end portion of the boss portion 80b. Fixed. Specifically, as shown in FIG. 2, a caulking portion 80c is provided on the outer peripheral portion of the boss portion 80b adjacent to the inner periphery of the through hole 81a, and the outer diameter of the boss portion 80b is enlarged by the caulking portion 80c. The boss portion 80b is tightly fitted in the through hole 81a. In FIG. 1B, the caulking portions 80c are provided at two locations facing the boss portion 80b in the radial direction. However, as shown in FIG. 4, the caulking portions 80c are provided on the entire circumference of the boss portion 80b. May be.

Next, the operation of the electromagnetic switch 1 will be described.
When the electromagnetic coil 7 is energized by turning on a start switch (not shown), an electromagnet is formed and the fixed iron core 8 is magnetized, so that an attractive force is generated between the core portion 80 of the fixed iron core 8 and the plunger 10. The plunger 10 moves toward the core portion 80 side (the right direction in FIG. 5) while pushing and shrinking the return spring 11. By the movement of the plunger 10, the plunger rod 12 is pushed out, and the movable contact 6 supported by the end of the plunger rod 12 comes into contact with the set of fixed contacts 5. Thereafter, the plunger 10 is further moved while compressing pressing contact pressure spring 18, and stops in contact with the end face of the core portion 80 (one end face of the base portion 80a).

As a result, a compressive load of the contact pressure spring 18 is applied to the movable contact 6, and the movable contact 6 is pressed against the set of fixed contacts 5, whereby the main contact is closed and power is supplied from the battery to the starter motor. .
After the engine is started, when the start switch is turned off and the energization of the electromagnetic coil 7 is stopped and the attraction force of the electromagnet disappears, the plunger 10 is pushed back toward the anti-core portion by the reaction force of the return spring 11. 6 is separated from the set of fixed contacts 5, the main contact is opened, and power supply to the starter motor is stopped.

(Effect of Example 1)
In the fixed iron core 8 of the present embodiment, after the boss portion 80b is press-fitted into the through hole 81a of the disk portion 81, a part or the entire circumference of the outer peripheral portion of the boss portion 80b adjacent to the inner periphery of the through hole 81a is caulked. As a result, a part or the entire circumference of the outer diameter of the boss part 80 b is enlarged, and the boss part 80 b is tightly fitted in the through hole 81 a of the disk part 81.
According to said structure, it can prevent that the boss | hub part 80b slips out from the through-hole 81a irrespective of the quality of each thin plate 82 used for the disk part 81. FIG. That is, when the inner diameter dimension of the round hole 82a formed in the thin plate 82 varies, the shape of the round hole 82a is not a perfect circle, and is slightly distorted, or the shear surface of the round hole 82a by the press is Even if it is insufficient, the press-fitting load of the boss part 80b with respect to the through hole 81a of the disk part 81 is not insufficient.

  As a result, when the number of times of operation of the electromagnetic switch 1 is extremely large, for example, when used in an engine automatic stop / restart system (generally called an idling stop, an eco-run system, etc.) that automatically controls engine stop and restart. However, when the plunger 10 is adsorbed to the base portion 80a, the boss portion 80b is removed from the through hole 81a by the return force (reaction force of the drive spring 20 (see FIG. 5) incorporated in the plunger 10) acting on the plunger 10. The core part 80 can be stably held without coming off, and the electromagnetic switch 1 with high reliability can be provided.

FIG. 6 is an enlarged sectional view showing the caulking portion 80 c of the fixed iron core 8.
In the fixed iron core 8 according to the second embodiment, the axial length of the boss portion 80b provided in the core portion 80 (the length protruding in the anti-plunger direction from the other end surface of the base portion 80a) is overlapped with a plurality of thin plates 82. The thickness of the combined disk portion 81 is longer than the axial thickness, and the tip end of the boss portion 80b protrudes from the through hole 81a in a state where the boss portion 80b is press-fitted into the through hole 81a of the disk portion 81. Thereafter (after the boss 80b is press-fitted into the through hole 81a), as shown in FIG. 6, a caulking portion 80c is provided on a part or the entire periphery of the boss 80b, and the caulking portion 80c is arranged in the radial direction. It is bent to the outside.
In the above configuration, since the disk portion 81 is sandwiched between the caulking portion 80c and the base portion 80a in the axial direction, even if the press-fitting load of the boss portion 80b press-fitted into the through hole 81a is somewhat insufficient, the boss portion 80b does not come out of the through hole 81a, the core part 80 can be stably held, and the electromagnetic switch 1 with high reliability can be provided.

FIG. 7 is an enlarged cross-sectional view showing the caulking portion 80 c of the fixed iron core 8.
In each thin plate 82 used for the disk portion 81, when the round hole 82a at the center is processed by a press, an R-shaped “pressing” is formed at the inner peripheral corner of the round hole 82a. Specifically, as shown in FIG. 8A, when the round hole 82a is punched by the punch 21 from one end side (the upper side in the drawing) to the other end side in the thickness direction, as shown in FIG. 8B. In addition, a “press droop” is formed at the inner peripheral corner of the round hole 82a that opens to one end in the thickness direction.
Therefore, in the third embodiment, when the thin plate 82 arranged in the outermost layer on the side opposite to the axial direction among the plurality of thin plates 82 constituting the disk portion 81 is called an end thin plate 82b, the end thin plate 82b is one end of "press Who" is formed is disposed toward the axial reaction base portion side of the disc portion 81 (shown right side of the disk portion 81 shown in FIG. 7).

On the other hand, the core portion 80 is inserted into the through hole 81a of the disc portion 81 by pressing the boss portion 80b into the disc portion 81, and then the axial end portion of the boss portion 80b is penetrated as shown in FIG. A caulking portion 80c is provided on a part or the entire circumference of the outer peripheral portion adjacent to the inner periphery of the hole 81a, and the caulking portion 80c is caulked in a state where the caulking portion 80c rides on the “press droop” formed on the end thin plate 82b. .
In this case, not only the outer diameter of the boss portion 80b is expanded in the radial direction, but also the caulking portion 80c rides on the “press droop”, whereby a caulking force can be applied to the disc portion 81 in the axial direction. This is effective for preventing the boss 80b from coming off.

FIG. 9 is an enlarged sectional view showing the caulking portion 80 c of the fixed iron core 8.
The fourth embodiment is an example in which “chamfering” is provided at the inner peripheral corner of the round hole 82a opened in the end thin plate 82b described in the third embodiment. The end sheet 82b is, for example, "chamfering" is formed on one end side in the thickness direction, one end side toward the axial reaction base portion side of the disc portion 81 (shown right side of the disk portion 81 shown in FIG. 9) Arranged.
On the other hand, the core portion 80 is inserted into the through hole 81a of the disc portion 81 by pressing the boss portion 80b into the disc portion 81, and then the axial end portion of the boss portion 80b is penetrated as shown in FIG. A caulking portion 80c is provided in a part or the entire circumference of the outer peripheral portion adjacent to the inner periphery of the hole 81a, and the caulking portion 80c is caulked in a state where the caulking portion 80c rides on a “chamfer” formed in the end thin plate 82b. Also in the present embodiment, as in the third embodiment, not only the outer diameter of the boss portion 80b is expanded in the radial direction, but also the caulking portion 80c rides on the “ chamfering ”, whereby the caulking force is exerted on the disc portion 81. Can be added in the axial direction, which is effective for preventing the boss 80b from coming off.

(Modification)
In the first embodiment, when the core portion 80 and the disk portion 81 are assembled, the boss portion 80b is press-fitted into the through hole 81a of the disk portion 81. However, it is not always necessary to press-fit, and the boss portion 80b is penetrated. After fitting into the hole 81a with a clearance fit, the outer peripheral portion of the boss portion 80b can be crimped and fixed.
Example 3 or Example 4 can be performed in combination with the configuration of Example 2 as well as Example 1.

(A) The top view of a fixed iron core, (b) It is sectional drawing of a fixed iron core (Example 1). It is an expanded sectional view of the caulking part shown in Drawing 1 (b). (A) The top view of a thin plate, (b) It is sectional drawing of a thin plate. It is a top view of a fixed iron core. It is sectional drawing of an electromagnetic switch. (Example 2) which is an expanded sectional view which shows the crimping part of a fixed iron core. (Example 3) which is an expanded sectional view which shows the crimping part of a fixed iron core. It is explanatory drawing at the time of punching out the round hole of a thin plate with a press (Example 3). (Example 4) which is an expanded sectional view which shows the crimping part of a fixed iron core. It is a perspective view of the fixed iron core which concerns on a prior art.

Explanation of symbols

1 Electromagnetic switch 5 Fixed contact (electrical contact)
6 Movable contacts (electrical contacts)
7 Electromagnetic coil 8 Fixed iron core 10 Plunger (movable iron core)
80 Core part of fixed core 80a Base part of core part 80b Boss part of core part 80c Crimp part of boss part 81 Disk part of fixed core 81a Through hole of disk part 82 Thin plate constituting disk part 82a Round formed on thin plate Hole

Claims (2)

An electromagnetic coil that forms an electromagnet when energized;
A fixed iron core magnetized by the electromagnet;
A movable core that is attracted to a magnetized fixed core;
An electromagnetic switch that opens and closes electrical contacts in conjunction with the movement of the movable iron core,
The fixed iron core is configured by stacking a plurality of thin plates each having a round hole formed in a central portion in a radial direction, and the circular hole of each thin plate communicates with each other in the plate thickness direction to form a through hole. A base portion having one end face in the axial direction disposed opposite to the movable iron core and a core portion having a boss projecting in the anti-movable iron core direction from the other end face of the base portion ,
When the thin plate disposed in the outermost layer on the axially opposite base side among the multiple thin plates constituting the disk portion is called an end thin plate, the end thin plate is moved from one end side to the other end side in the plate thickness direction. By punching out the round hole with a press toward the inner side corner portion of the round hole that opens to one end side in the plate thickness direction, the “press droop” is formed, and the “press droop” is formed. One end side of the end thin plate is disposed toward the axially opposite base side of the disk part,
The core part, together with the assembled to the disc portion fitted to the boss portion in the through hole of the disc portion, the axial end of the boss portion, an outer peripheral portion close to the inner periphery of the through hole An electromagnetic switch characterized in that a caulking portion is provided on a part or the entire periphery of the caulking portion, and the caulking portion is caulked in a state where the caulking portion rides on the “press droop”. An electromagnetic coil that forms an electromagnet when energized;
A fixed iron core magnetized by the electromagnet;
A movable core that is attracted to a magnetized fixed core;
An electromagnetic switch that opens and closes electrical contacts in conjunction with the movement of the movable iron core,
The fixed iron core is configured by stacking a plurality of thin plates each having a round hole formed in a central portion in a radial direction, and the circular hole of each thin plate communicates with each other in the plate thickness direction to form a through hole. A base portion having one end face in the axial direction disposed opposite to the movable iron core and a core portion having a boss projecting in the anti-movable iron core direction from the other end face of the base portion ,
When a thin plate disposed in the outermost layer on the axially opposite base portion side is referred to as an end thin plate among a plurality of thin plates constituting the disk portion, this end thin plate is the round opening that opens on one end side in the plate thickness direction. "Chamfering" is formed at the inner peripheral corner of the hole, and one end side of the end thin plate on which the "chamfering" is formed is arranged toward the axially opposite base side of the disk part,
The core part, together with the assembled to the disc portion fitted to the boss portion in the through hole of the disc portion, the axial end of the boss portion, an outer peripheral portion close to the inner periphery of the through hole An electromagnetic switch, characterized in that a caulking portion is provided on a part or all of the circumference thereof, and the caulking portion is caulked in a state where the caulking portion rides on the “chamfering”.

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