JP6237176B2 - magnetic switch - Google Patents

Description

  The present invention relates to a magnet switch that opens and closes a main contact for supplying a current to a motor in a starter, for example.

  As a magnet switch that opens and closes the main contact for flowing current to the motor in the starter, a coil, a plunger that moves to one end in the axial direction when the coil is energized, and a return spring that returns the plunger to the other end in the axial direction when coil energization is stopped There is something with. When the coil is energized, the contact is closed by moving the plunger toward one end in the axial direction, and when the coil is not energized, the contact is opened by moving toward the other end in the axial direction by the biasing force of the return spring (see Patent Document 1).

Conventionally, the movement of the plunger toward the other end in the axial direction has been restricted by the contact between the end cover and the insulator attached to the outer periphery of the plunger at the other end in the axial direction of the movable contact.
However, in this case, there is a problem that a large collision sound is generated when the collision force when the insulator and the end cover come into contact with each other is large.
Further, when the distance between the contacts is small, there is a problem that if the impact force between the insulator and the end cover is large, the plunger will bounce and the contacts will close unintentionally.

JP 2012-225189 A

  Therefore, the present invention has been made to solve the above-described problems, and the purpose of the present invention is to determine the return position when the plunger is returned by the return spring when the coil energization is stopped by the contact between the insulator and the end cover. In the regulated magnet switch, the collision force when the insulator and the end cover come into contact with each other is to be reduced.

The magnet switch of the present invention includes a coil, a plunger, a return spring, a movable contact, a fixed contact, an insulator, and an end cover.
The coil forms an electromagnet when energized.
The plunger is attracted by the electromagnet and moves the inner circumference of the coil toward one end in the axial direction.
The return spring biases the plunger toward the other end in the axial direction.

The movable contact is attached to the outer periphery on the one axial end side from the other axial end surface of the plunger, and moves in the axial direction as the plunger moves.
The fixed contact is disposed opposite to one end side in the axial direction of the movable contact, and contacts and separates from the movable contact by the movement of the movable contact.

The insulator is mounted on the outer periphery on the one axial end side from the other axial end surface of the plunger, and is disposed on the other axial end side of the movable contact.
The end cover covers the other end in the axial direction of the plunger and the coil, and has a restricting portion that restricts the movement of the plunger toward the other end in the axial direction by contacting the insulator.

  When the coil is energized, the magnet switch moves the movable contact with the plunger toward one end in the axial direction, the movable contact contacts the fixed contact, and when the coil energization stops, the plunger and the movable contact are moved in the axial direction by the urging force of the return spring. The movable contact moves away from the fixed contact by moving to the other end side.

And the magnet switch of this invention is equipped with the elastic member fixed to either the axial direction other end surface of a plunger, or the surface where the axial direction other end surface of the plunger of an end cover opposes.
Further, the insulator has a tapered portion whose diameter decreases toward the other end in the axial direction, the restricting portion has a tapered shape similar to the tapered portion of the insulator, and further, the other end surface in the axial direction of the plunger faces. The surface to be present exists on the other end side in the axial direction of the restriction portion.
Then, when the plunger moves to the other end side in the axial direction, first, the other end surface in the axial direction of the plunger comes into contact with the surface of the end cover (the surface opposite to the other end surface in the axial direction of the plunger) via the elastic member, As the elastic member bends, the tapered portion of the insulator comes into contact with the restricting portion.

  According to this, since the impact is absorbed by the elastic member before the insulator comes into contact with the end cover, the collision force between the insulator and the end cover can be reduced. Thereby, a collision sound can be reduced and the bounce of a plunger can also be suppressed.

(Example 1) which is sectional drawing of a starter. (Example 1) which is the top view seen from the axial direction other end side of the starter. (Example 1) which is the elements on larger scale of FIG. (Example 1) which is sectional drawing of a magnet switch. (Example 1) which is an expanded sectional view of the principal part of a magnet switch. (Example 1) which is an expanded sectional view of the principal part of a magnet switch. (Example 2) which is an expanded sectional view of the principal part of a magnet switch. (Example 3) which is an expanded sectional view of the principal part of a magnet switch. It is sectional drawing of a magnet switch (modification).

  The mode for carrying out the present invention will be described in detail with reference to the following examples.

[Example 1]
[Configuration of Example 1]
The configuration of the first embodiment will be described with reference to FIGS.
In the first embodiment, an example in which the present invention is employed in a magnet switch 2 mounted on a deceleration starter 1 will be described.
The cross-sectional view of the magnet switch 2 is a cross-sectional view taken along the line I-O-I in FIG.

  As shown in FIG. 1, the decelerating starter 1 is supported on a motor 3 that generates a rotational force, a pinion shaft 5 that is arranged parallel to the armature shaft 4 of the motor 3, and an outer periphery of the pinion shaft 5. The pinion 6 that rotates together with the pinion shaft 5, the speed reduction device (described later) that reduces the rotational speed of the motor 3 and amplifies the drive torque, and the drive torque amplified by this speed reduction device is applied to the pinion shaft 5. A clutch 7 for transmission and a magnet switch or the like disposed on the same axis as the pinion shaft 5 are configured.

The motor 3 is disposed on the outer circumference of the commutator 8, an electromagnet field (described below) that forms a magnetic field, an armature 9 having a commutator 8 on the rear end side shaft of the armature shaft 4, and the like. This is a known commutator motor composed of a brush 10 and the like.
The electromagnet field forms a magnetic circuit, and a field magnetic pole 13 fixed by a screw 12 to the inner periphery of the yoke 11 that also serves as a housing of the motor 3, and a rectangular wire wound around the field magnetic pole 13. The field coil 14 is configured. Instead of the electromagnet field, a permanent magnet field in which a plurality of permanent magnets are arranged on the inner periphery of the yoke 11 can be adopted.

The pinion shaft 5 is inserted into the inner periphery of a spline tube 15 to be described later and is helically splined. The pinion shaft 5 is provided so as to be movable while rotating in the axial direction (the left-right direction in the drawing) with respect to the spline tube 15.
Hereinafter, the illustrated left side in the axial direction including the pinion shaft 5 and the magnet switch 2 is referred to as one axial end side, and the illustrated right side is referred to as the other axial end side. Note that the pinion shaft 5 moves to one end in the axial direction, so that the pinion 6 meshes with the ring gear G.

  The pinion shaft 5 is formed with a hole recessed from the end surface on the other end side in the axial direction toward one end side in the axial direction, and a steel ball 16 is disposed in the hole.

  The pinion 6 is supported by being directly spline fitted to the outer periphery of the pinion shaft 5 protruding from one axial end surface of the spline tube 15, and is splined by a pinion spring 17 disposed between the pinion shaft 5 and the pinion 6. The tube 15 is pressed against one end surface in the axial direction.

  The end of the spline tube 15 on one end side in the axial direction is rotatably supported by the starter housing 19 via the ball bearing 18, and the end on the other end side in the axial direction is rotatable on the center case 21 via the ball bearing 20. It is supported by. The center case 21 is disposed adjacent to the other axial end side of the starter housing 19.

    The reduction gear includes a drive gear 23 formed at an end of the armature shaft 4 on the side opposite to the commutator, an idle gear 24 that meshes with the drive gear 23, and a gear train that meshes with the idle gear 24. Composed.

  The clutch 7 is, for example, a roller type one-way clutch, a clutch outer 7a that forms a plurality of cam surfaces on the inner periphery, and a clutch inner (described below) disposed on the inner periphery side of the clutch outer 7a. The roller 7b is disposed between the cam surface of the clutch outer 7a and the outer peripheral surface of the clutch inner, and a spring 7c that urges the roller 7b toward the cam surface.

The rotational driving force of the motor 3 is transmitted to the clutch outer 7a through the clutch gear 25.
The clutch inner is formed by the spline tube 15 described above. That is, the spline tube 15 also serves as a clutch inner.
The roller 7b transmits the rotation of the clutch outer 7a to the clutch inner (spline tube 15), and interrupts the power transmission from the clutch inner to the clutch outer 7a.

[Configuration of Magnet Switch 2 According to the Present Invention]
The configuration of the magnet switch 2 will be described mainly with reference to FIG.
The magnet switch 2 accommodates in the switch case a solenoid that opens and closes a main contact (described later) connected to the power circuit of the motor 3 while pushing the pinion shaft 5 toward one end in the axial direction by using the attractive force of the electromagnet. It has become.

  The switch case is provided integrally with the center case 21 and surrounds the outer periphery of one end of the solenoid in the axial direction. The switch case is connected to the other end in the axial direction of the metal frame 28 and connected to the other end of the solenoid in the axial direction. A resin frame 29 that surrounds the outer periphery and a metal end cover 30 that closes the opening on the other axial end side of the resin frame 29 are configured.

  The solenoid includes a coil 35 that forms an electromagnet when energized, a plunger 36 that moves the inner periphery of the coil 35 in the axial direction (left-right direction in the drawing), a fixed iron core 37 that is magnetized by the electromagnet and attracts the plunger 36, and a coil An annular core plate 38 disposed on one end side in the axial direction of the shaft 35, a shaft 39 that transmits the movement of the plunger 36 to the pinion shaft 5 via the steel ball 16, and a return spring 40 that pushes back the plunger 36 when coil energization is stopped. And a drive spring 41 for storing a reaction force for pushing the pinion 6 into the ring gear G of the engine.

  The coil 35 is configured by, for example, winding a copper wire with an insulation coating around a resin bobbin 42. A cylindrical sleeve 43 made of a nonmagnetic metal (for example, stainless steel) that guides the movement of the plunger 36 is inserted into the inner periphery of the bobbin 42.

  The plunger 36 is provided in a stepped shape in which a step is formed on the outer peripheral surface in the radial direction so that the other end portion in the axial direction has a small diameter, and a sliding portion 36 a accommodated in the inner periphery of the coil 35. The sliding portion 36a has a small-diameter portion 36c formed on the other end side in the axial direction through the step portion 36b and having a smaller diameter than the sliding portion 36a.

The plunger 36 is formed with a hollow hole 44 penetrating the central portion in the radial direction in the longitudinal direction, and has a small-diameter hole portion 44 a having a small hole diameter on one end side in the axial direction of the hollow hole 44. The opening at the other axial end of the hollow hole 44 is defined as an opening 44b.
A washer 45 having an outer diameter larger than that of the small diameter portion 36c is fixed to the other axial end surface 36d of the plunger 36. The hole 45a of the washer 45 is smaller than the opening 44b.

The fixed iron core 37 is provided in an annular shape whose central portion in the radial direction is opened in a cylindrical shape, is inserted into the inner periphery of one axial end portion of the cylindrical sleeve 43, and is disposed so as to face the plunger 36 in the axial direction. .
The core plate 38 is caulked and fixed to the fixed iron core 37 and is magnetically coupled.
A core stationery 50 disposed on the outer periphery of the coil 35 is magnetically connected to the core plate 38 to form a magnetic circuit.

  The shaft 39 is assembled to the plunger 36 through the small diameter hole 44 a of the plunger 36. A flange portion 39a having an outer diameter larger than that of the small-diameter hole portion 44a is provided at the end portion of the shaft 39 that enters the other axial end of the hollow hole 44 from the small-diameter hole portion 44a. Further, one axial end side of the shaft 39 protruding from the hollow hole 44 passes through the inner periphery of the fixed iron core 37 and protrudes so as to contact the steel ball 16 (see FIG. 1).

  The return spring 40 is disposed on the outer periphery of the shaft 39, and one end in the axial direction is supported by the steel ball 16 and the other end in the axial direction is supported by the peripheral edge on the one end side in the axial direction of the small diameter hole 44a.

  The drive spring 41 is disposed in the hollow hole 44, and one end in the axial direction is supported by the peripheral edge on the one end side in the axial direction of the small diameter hole portion 44 a and the other end in the axial direction is supported by the washer 45.

  The main contacts are a set of fixed contacts 56 connected to the power supply circuit of the motor 3 via two terminal bolts 54 and 55, and a movable contact 57 that electrically connects and disconnects between the set of fixed contacts 56. The movable contact 57 abuts against a set of fixed contacts 56 and the fixed contacts 56 are electrically connected to each other through the movable contact 57, whereby the main contact is closed (turned on). The main contact is opened (turned off) by being electrically disconnected between the fixed contacts 56 apart from the set of fixed contacts 56.

  The two terminal bolts 54 and 55 are a B terminal bolt 54 and an M terminal bolt 55 each having a male screw portion formed on the outer periphery. A battery cable terminal connected to the positive terminal of the battery B is connected to the B terminal bolt 54, and a motor lead terminal connected to the positive brush 10 of the motor 3 is connected to the M terminal bolt 55.

  The set of fixed contacts 56 is provided separately from the B terminal bolt 54 and the M terminal bolt 55, and one fixed contact 56 is electrically connected to the B terminal bolt 54 and the other fixed contact 56 is electrically connected to the M terminal bolt 55. Fixed to connect.

The movable contact 57 has a plate shape having a hole through which the small-diameter portion 36c can be inserted, and is held on the outer periphery of the small-diameter portion 36c via a resin insulating plate 63 and an insulating bush 64.
The insulating plate 63 has an annular shape, and is disposed on the outer periphery of the small-diameter portion 36 c between the step portion 36 b and the movable contact 57.

The insulating bush 64 is formed with a bush portion 64a that surrounds the outer peripheral surface of the small-diameter portion 36c and insulates the movable contact 57, and has an outer diameter larger than the bush portion 64a on the other axial end of the bush portion 64a. And a head 64b disposed on the other axial end of the movable contact 57.
The head portion 64 b has a tapered portion that decreases in diameter toward the other end in the axial direction, and this tapered portion can contact the end cover 30.

The movable contact 57 is urged by a contact pressure spring 65 for applying contact pressure when the main contact is closed.
The contact pressure spring 65 is disposed on the outer periphery of the small diameter portion 36 c, and one end in the axial direction is supported by the insulating bush 64 and the other end in the axial direction is supported by the washer 45.

The end cover 30 has a bottomed cup portion 30 a that covers the small-diameter portion 36 c, and the bottom surface 30 b of the cup portion 30 a faces the other axial end surface 36 d of the plunger 36.
And the taper-shaped control part 30c in which the taper part of the head part 64b can surface-contact is provided in the axial direction one end part of the cup part 30a.

  The return position of the plunger 36, that is, the position where the plunger 36 is pushed back by the urging force of the return spring 40 when the energizing force of the electromagnet is lost due to the stop of energization of the coil 35, is restricted with the head 64 b. It is regulated by contact with the portion 30c.

[Features of this embodiment]
The magnet switch 2 of the present embodiment includes an elastic member 70 fixed to the other axial end surface 36 d of the plunger 36.
The elastic member 70 is formed in a disk shape by a material used as a cushioning material such as a rubber material, for example.
In the present embodiment, for example, the elastic member 70 is fixed to the washer 45 by an adhesive, and the elastic member 70 is fixed to the other axial end surface 36d via the washer 45.

The dimension of the elastic member 70 is such that the head portion 64b and the regulating portion 30c are separated when the other axial end surface 36d of the plunger 36 contacts the bottom surface 30b of the end cover 30 via the elastic member 70. Is set.
Further, when the plunger 36 moves to the other end in the axial direction, the other end surface 36 d in the axial direction of the plunger 36 comes into contact with the bottom surface 30 b of the end cover 30 via the elastic member 70, and is elasticized by the urging force of the return spring 40. The elastic coefficient of the elastic member 70 is set such that the member 70 is bent and the head 64b can then come into contact with the restricting portion 30c.

[Effects of this embodiment]
The effect of a present Example is demonstrated using FIGS.
FIG. 4 shows a state where the coil 35 is energized.
In a state where the coil 35 is energized, the plunger 36 is attracted to the fixed iron core 37, and the plunger 36 is positioned on one end side in the axial direction. At this time, the pinion shaft 5 is pushed out by the shaft 39, and the movable contact 57 comes into contact with the fixed contact 56, so that the motor 3 is energized.

When the power supply to the coil 35 is stopped from the state of FIG. 4, the plunger 36 is pushed back to the other end side in the axial direction by the urging force of the return spring 40.
Then, as shown in FIG. 5, first, the elastic member 70 and the bottom surface 30b abut. At this time, the head 64b and the restricting portion 30c are separated from each other.
Next, as shown in FIG. 6, the elastic member 70 is bent, so that the head portion 64b comes into contact with the restricting portion 30c.

According to this, since the impact is absorbed by the elastic member 70 before the head portion 64b contacts the restriction portion 30c, the collision force between the head portion 64b and the restriction portion 30c can be reduced.
Thereby, the collision sound by the collision with the head 64b and the control part 30c can be reduced, and the bounce of the plunger 36 can also be suppressed.

[Example 2]
A second embodiment will be described with reference to FIG. 7 with a focus on differences from the first embodiment.
In addition, the same code | symbol as Example 1 shows the same functional thing, Comprising: The previous description is referred.
The magnet switch of the present embodiment includes a claw 71 integrally provided on one end side in the axial direction of the elastic member 70, and the elastic member 70 is fixed to the plunger 36 by the engagement of the claw 71 and the washer 45.

As shown in FIG. 6, the claw 71 includes a bush 71a protruding from one axial end surface of the elastic member 70 and a claw portion 71b having a diameter larger than that of the bush 71a.
The bush 71a can be fitted into the hole 45a of the washer 45 with a predetermined dimensional tolerance. The claw portion 71b has an outer diameter larger than that of the hole 45a in an unloaded state, and becomes smaller in diameter toward one end in the axial direction.

When the claw portion 71b is inserted into the hole 45a of the washer 45 while being elastically deformed, the claw portion 71b is restored on one end side in the axial direction of the hole 45a after passing through the hole 45a, and the peripheral edge and the claw on one end side in the axial direction of the hole 45a. The elastic member 70 is fixed to the plunger 36 by engaging with the portion 71b.
The elastic member 70 and the claw 71 are provided with a through hole 72 penetrating in the axial direction, and the through hole communicates with the hollow hole 44.

Also according to the present embodiment, the same effects as those of the first embodiment can be achieved.
In addition, the elastic member 70 can be reliably fixed to the plunger 36 without using an adhesive.

Example 3
A third embodiment will be described with reference to FIG. 8 with a focus on differences from the first embodiment.
In addition, the same code | symbol as Example 1 shows the same functional thing, Comprising: The previous description is referred.
In this embodiment, a thin metal plate 75 is fixed to the contact surface of the elastic member 70 with the bottom surface 30b.

Also according to the present embodiment, the same effects as those of the first embodiment can be achieved.
In addition, the elastic member 70 does not directly contact the metal end cover 30 but the metal plate 75 contacts. Therefore, wear of the elastic member 70 can be suppressed, and wear debris caused by wear can be prevented from adhering between the contacts. Further, sticking of the elastic member 70 to the end cover 30 due to temperature rise can be prevented.

[Modification]
The magnet switch 2 of the embodiment pushes the pinion shaft 5 in the opposite switch direction by one plunger 36 and opens and closes the main contact connected to the power supply circuit of the motor 3.
However, the present invention may be applied to a tandem type magnet switch (for example, see Patent Document 1) in which the pinion shaft 5 is pushed out and the main contact is opened and closed by separate solenoids.

That is, the magnet switch 2 includes a solenoid SL1 for pushing out the pinion shaft 5 and a solenoid SL2 for opening and closing the main contact as shown in FIG. An elastic member 70 may be provided.
The coil and plunger of the solenoid SL2 correspond to the coil 35 and plunger 36 of the first embodiment.
Also in this case, the same effects as those of the first embodiment are obtained.
In the tandem type, since the distance between the fixed contact 56 and the movable contact 57 is narrow, when the plunger bounces, the contact may be closed unintentionally. For this reason, it can be said that reducing the bounce of the plunger is a particularly effective effect.

  In the embodiment, the elastic member 70 is fixed to the other axial end surface 36 d of the plunger 36, but the elastic member 70 may be fixed to the bottom surface 30 b of the end cover 30.

DESCRIPTION OF SYMBOLS 1 Starter, 2 Magnet switch, 30 End cover, 30b Bottom surface (surface where the other axial end surface of a plunger opposes), 30c Restriction part, 35 Coil, 36 Plunger, 36d The other axial end surface of a plunger, 40 Return spring, 56 Fixation Contact, 57 Movable contact, 64b Insulating bush head (insulator), 70 Elastic member

Claims (5)

A coil (35) that forms an electromagnet upon energization;
A plunger (36) that is attracted by the electromagnet and moves to the one end side in the axial direction of the inner periphery of the coil (35);
A return spring (40) for urging the plunger (36) toward the other axial end;
A movable contact (57) attached to the outer periphery of one end side in the axial direction from the other axial end surface (36d) of the plunger (36) and moving in the axial direction as the plunger moves;
A fixed contact (56) which is disposed opposite to one end side in the axial direction of the movable contact (57) and contacts and separates from the movable contact (57) by the movement of the movable contact (57);
An insulator (64b) that is mounted on the outer periphery on one axial end side of the plunger (36) from the other axial end surface (36d) and disposed on the other axial end side of the movable contact (57);
A restricting portion that covers the other end in the axial direction of the plunger (36) and the coil (35) and restricts the movement of the plunger (36) toward the other end in the axial direction by contacting the insulator (64b). An end cover (30) having (30c),
When the coil is energized, the plunger (36) and the movable contact (57) move toward one end in the axial direction, the movable contact (57) contacts the fixed contact (56), and when the coil energization is stopped, the return In the magnet switch in which the plunger (36) and the movable contact (57) are moved to the other axial end side by the biasing force of the spring (40), and the movable contact (57) is separated from the fixed contact (56).
The other end surface (36d) in the axial direction of the plunger (36) or the other end surface (36d) in the axial direction of the plunger (36) of the end cover (30) is fixed to one of the opposing surfaces (30b). An elastic member (70),
The insulator (64b) has a tapered portion whose diameter decreases toward the other end in the axial direction,
The restricting portion (30c) has a tapered shape similar to the tapered portion of the insulator (64b),
The surface (30b) opposite to the other axial end surface (36d) of the plunger (36) exists on the other axial end side of the restricting portion (30c),
When the plunger (36) moves to the other end side in the axial direction, first, the other end surface (36d) in the axial direction of the plunger (36) is placed on the surface ( 30) of the end cover (30) via the elastic member (70). 30b) , and then the elastic member (70) bends so that the tapered portion of the insulator (64b) abuts on the restricting portion (30c). The magnet switch according to claim 1,
The metal plate (75) is fixed to the contact surface of the elastic member (70) with the end cover (30) or the contact surface of the elastic member (70) with the plunger (36). Features a magnetic switch. The magnet switch according to claim 1 or 2,
The plunger (36) is formed with an axial hole (44) having an opening (44b) in the other axial end surface (36d), and has a diameter on the other axial end surface (36d) than the opening (44b). A washer (45) with a small hole (45a) is fixed,
A claw (71) provided integrally with one end of the elastic member (70) in the axial direction, elastically deformed when passing through the hole (45a), and restored when passing through the hole (45a),
The magnet switch, wherein the elastic member (70) is fixed to the plunger (36) by engagement of the claw (71) and the washer (45). The magnet switch according to any one of claims 1 to 3,
A magnet switch used for a starter (1) for starting the engine by transmitting the rotational force of a motor (3) to a pinion (6) meshing with an engine ring gear (G). The magnet switch according to claim 4, wherein
A first solenoid (SL1) for pushing out the pinion (6) to the ring gear (G), and a second solenoid (SL2) for opening and closing a main contact for flowing a current to the motor (3) A magnet switch comprising:

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