JP3644316B2 - Magnetic switch for starter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a magnet switch used in a starter for starting an engine.
[0002]
[Prior art]
As a prior art, there is a magnet switch described in, for example, a reference number 80-041 (issued on September 15, 1991) of the Nippon Denso public technical report.
In the magnet switch, a waterproof rubber packing is sandwiched between a frame and a switch cover. As shown in FIG. 7, the packing 100 is provided in a substantially pentagonal annular body, and the outer peripheral surface other than the upper end portion 101 on the motor side (upper side in FIG. 7) arranged in parallel with the magnet switch is a switch cover. The inner peripheral surface 101 a of the motor-side upper end portion 101 is disposed in a state of being in contact with the inner wall surface 112 provided on the switch cover 110.
[0003]
[Problems to be solved by the invention]
However, in the above-described magnet switch, when the thickness of the packing 100 is increased, the rubber volume to be tightened is increased if an attempt is made to secure the sealing performance by setting the compression rate to be equal to that of the conventional one. As a result, since the inner peripheral surface 101a is restricted by the inner wall surface 112 of the switch cover 110 at the motor-side upper end portion 101 of the packing 100, a force that tries to protrude outward is generated as shown in FIG. There is a possibility that the packing 100 protrudes outward from the sealing surface of the frame.
[0004]
Even if the motor-side upper end 101 of the packing 100 does not protrude outward during assembly, it remains on the motor-side upper end 101 of the packing 100 when the repulsive force in the tightening direction of the packing 100 is weakened by environmental stress such as heat. There was a possibility that the motor-side upper end portion 101 may protrude to the outside by the fact that the force of expanding to the outside overcomes the frictional force.
The present invention has been made based on the above circumstances, and an object of the present invention is to provide a magnet switch for a starter that can prevent the packing from protruding to the outside even when there is no case-side wall facing the outer peripheral surface of the packing. There is to do.
[0005]
[Means for Solving the Problems]
(Means of Claim 1)
It has a first case and a second case that are adjacent to each other with a rubber packing interposed therebetween, and the first case or the second case faces the outer peripheral surface of the packing except for a part in the circumferential direction. the outer peripheral wall portion is provided with a packing includes a regulating portion protruding to the outside is restricted by the outer peripheral wall portion, as well as organic and non-regulated site which is not regulated by the outer peripheral wall portion, the inner peripheral side of the packing Is a magnet switch for a starter in which a gap is provided over the entire circumference, and the packing is provided with a protruding portion protruding inward on the inner peripheral surface of the non-regulated portion , and this protruding portion is the inner portion of the packing. It arrange | positions in the state contact | abutted to the opposing wall surface which has a clearance gap in the peripheral side, and is characterized by the above-mentioned.
[0006]
According to this configuration, since there is a gap between the non-regulated portion of the packing and the opposing wall surface facing the inside, the stress generated in the non-regulated portion of the packing when a tightening force is applied to the packing. Can escape to the inside . As a result , the force to expand outward can be reduced, so that the non-regulated portion of the packing can be prevented from protruding outward with respect to the seal surface of the case.
Even if a gap is provided between the inner peripheral surface of the non-regulated part and the opposing wall surface, the protrusion provided on the inner peripheral surface of the non-regulating part is positioned in contact with the opposing wall surface, so that the inner side of the packing Can be prevented from falling off.
[0008]
(Means of Claim 2)
2. The starter magnet switch according to claim 1, wherein the first case or the second case is provided such that the width of the seal surface that contacts the non-regulated portion of the packing is smaller than the width of the non-regulated portion of the packing. Is characterized in that the inner peripheral end in the width direction of the non-regulated portion is provided so as to protrude inward from the inner peripheral end in the width direction of the seal surface contacting the non-regulated portion. According to this configuration, even when the inner peripheral surface of the non-regulated part is in contact with the opposing wall surface, when the tightening force is applied to the packing, the inner peripheral part of the non-regulated part that does not contact the seal surface of the case is It can bulge between the inner peripheral wall surface and the opposing wall surface. As a result, since the bulging portion becomes a resistance and can be opposed to the force generated on the non-regulated portion to bulge outward, it is possible to prevent the non-regulated portion of the packing from protruding outward from the seal surface of the case.
[0009]
(Means of claim 3)
3. The starter magnet switch according to claim 1, wherein the packing is an annular body, has a non-regulated portion in a part of the annular body in the circumferential direction, and is provided at a substantially central portion in the circumferential direction of the non-regulated portion. A protrusion is provided.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a plan view (plan view seen from the inside of the switch cover) showing an assembled state of the packing with respect to the switch cover.
As shown in FIGS. 3 and 4, for example, the magnet switch 1 of the present embodiment is used in a reduction type starter A that drives the pinion gear 3 by reducing the rotational speed of the starting motor 2, and a housing 4 to be mounted on the engine. Via the starter motor 2. Note that the structure and operation of the starter A are very well known, and a description thereof is omitted here.
[0011]
As shown in FIG. 2, the magnet switch 1 includes a solenoid 6 wound around a bobbin 5 and components such as a plunger 7 that moves by receiving the magnetic force of the solenoid 6, and constitutes an outer shell together with the housing 4. The center case 8, the terminal case 9, and the switch cover 10 are covered.
The solenoid 6 includes an attraction coil 6a and a holding coil 6b. The attraction coil 6a and the holding coil 6b are wound around the outer periphery of the bobbin 5 and wound together with the stator 11 that forms part of the magnetic circuit. It is held inside.
[0012]
The plunger 7 receives the magnetic force of the solenoid 6 and is attracted to the stator 11 side (left side in FIG. 2). When the magnetic force of the solenoid 6 disappears, the plunger 7 is urged and pushed back by a return spring (not shown). The provided inclined surface 7a comes into contact with the tapered surface 10a provided on the switch cover 10 and stops (the state shown in FIG. 2).
Further, a movable contact 13 is attached to the head side of the plunger 7 via an insulating bush 12, and when the plunger 7 is sucked and moved to the stator 11 side, the movable contact 13 is brought into contact with a set of fixed contacts (not shown). In contact, the energization circuit of the starter motor 2 is closed.
[0013]
The center case 8 is formed by, for example, aluminum die casting, and is disposed on the rear side of the housing 4 so as to cover the outer periphery of the stator 11 and the solenoid 6.
The terminal case 9 is manufactured from, for example, an insulating synthetic resin, and is disposed on the rear side of the center case 8. The waterproof first packing 14 (see FIG. 2) is sandwiched between the terminal case 9 and the center case 8. Assembled. A terminal bolt 15 (see FIG. 4) connected to the fixed contact and a switch terminal 16 (see FIG. 4) connected to the key switch circuit of the vehicle are attached to the terminal case 9.
[0014]
The switch cover 10 is press-molded from, for example, an iron plate, and is put on the rear end opening of the terminal case 9 via a waterproof second packing 17, and together with the terminal case 9 by a plurality of bolts 18 (see FIG. 4). It is fixed to the center case 8.
As shown in FIG. 4, the switch cover 10 has a substantially pentagonal shape when viewed from the rear side of the starter A, and has round holes 10b (see FIG. 1) for passing bolts 18 through three corners. ) Is opened.
[0015]
The outer peripheral edge portion of the switch cover 10 is bent toward the terminal case 9 except for a part in the circumferential direction, and the bent portion 10c covers the outer peripheral surface of the second packing 17 sandwiched between the terminal case 9 and the switch cover 10. ing. However, a bent portion 10c is provided at the outer peripheral edge (upper edge in FIG. 1) on the starter motor 2 side, which is the “part in the circumferential direction”, in order to ensure a gap with the yoke of the starter motor 2. (See FIG. 1).
Further, the switch cover 10 is provided with the above-described tapered surface 10a, and on the outside of the tapered surface 10a, an inner wall surface 10d having a plane along the axial direction (left-right direction in FIG. 2) is provided in an annular shape. A packing space for arranging the second packing 17 is formed outside the inner wall surface 10d.
[0016]
As shown in FIG. 1, the second packing 17 is provided on a substantially pentagonal annular body along the planar shape of the switch cover 10, and has three corner portions (round portions provided on the switch cover 10. A round hole 17a for passing the bolt 18 is formed in the same position as the hole). The second packing 17 is covered with the switch cover 10 (the state shown in FIG. 1), and the remaining outer peripheral surface of the switch cover 10 except for the motor-side upper end portion 17A (the non-regulated portion of the present invention). It faces the bent portion 10c with a slight gap, and the inner peripheral surface of the second packing 17 faces the inner wall surface 10d of the switch cover 10 with a slight gap over the entire circumference. . Further, the motor-side upper end portion 17 </ b> A is provided with a shape in which an outer peripheral surface thereof substantially follows the outer peripheral edge of the switch cover 10.
[0017]
Furthermore, as shown in FIG. 1, the second packing 17 is integrally provided with a protrusion 17b on the inner peripheral surface of the motor-side upper end 17A. The protrusion 17b is located at a substantially central portion in the circumferential direction of the motor-side upper end 17A, and is provided in such a size that the tip of the protrusion 17b contacts the inner wall surface 10d of the switch cover 10.
The thickness of the second packing 17 (the dimension in the left-right direction in FIG. 2) is thicker than that of the conventional product, and has a thickness corresponding to the height of the bolt head, for example.
[0018]
Next, the operation and effect of the present embodiment will be described.
The second packing 17 sandwiched between the terminal case 9 and the switch cover 10 receives the tightening force of the bolt 18 and is compressed in the axial direction. Since the second packing 17 has an axial thickness larger than that of the conventional product, if the compression rate is set to be equal to that of the conventional product to secure the sealing performance, the volume of the rubber to be tightened is increased, and the conventional product having a small thickness. As compared with the above, the internal stress of the second packing 17 increases.
[0019]
In this case, if the entire inner peripheral surface is in contact with the inner wall surface 10d of the switch cover 10 at the motor-side upper end portion 17A of the second packing 17 as in the prior art, the internal stress of the second packing 17 is reduced to the motor side. The upper end portion 17A works in a direction that protrudes outward with respect to the seal surface 9a of the terminal case 9 (surface that contacts the motor-side upper end portion 17A).
On the other hand, in the configuration of the present embodiment, since there is a slight gap between the inner peripheral surface of the motor-side upper end portion 17A and the inner wall surface 10d of the switch cover 10, the second packing 17 has a motor side. The internal stress generated in the upper end portion 17A can be released to the inside. As a result, the force acting in the direction of protruding outward can be reduced, so that the motor-side upper end 17A of the second packing 17 can be prevented from protruding outward from the seal surface 9a of the terminal case 9.
[0020]
Further, the motor-side upper end portion 17A of the second packing 17 is positioned so that the protrusion 17b provided on the inner peripheral surface thereof is in contact with the inner wall surface 10d of the switch cover 10, so that the inner side of the motor-side upper end portion 17A Even if a gap is provided between the peripheral surface and the inner wall surface 10d of the switch cover 10, it is possible to prevent the motor-side upper end portion 17A from falling off inward. The internal stress generated in the motor-side upper end portion 17A can also be obtained by providing a gap over the entire circumference between the inner peripheral surface of the second packing 17 and the inner wall surface 10d of the switch cover 10 without providing the protrusion 17b. However, in this case, the position of the second packing 17 is easily displaced with respect to the seal surface 9a of the terminal case 9. Accordingly, considering that the second packing 17 is displaced in advance, it is necessary to increase the rubber width of the second packing 17, which increases the material cost and causes an increase in cost. On the other hand, in the configuration of the present embodiment, the second packing 17 can be positioned simply by providing the protrusion 17b, so that the increase in material cost can be extremely reduced.
[0021]
In this embodiment, the protrusion 17b provided on the inner peripheral surface of the motor-side upper end portion 17A need not be limited to one place, and may be two or more places.
Further, the space between the housing 4 and the switch cover 10 is not divided into a single frame but a center case 8 and a terminal case 9, but the center case 8 and the terminal case 9 are integrated into a single frame. You may do it.
[0022]
(Second embodiment)
In the present embodiment, as shown in FIG. 2, a step is formed on the inner peripheral side of the seal surface 9a of the terminal case 9 that contacts the motor-side upper end portion 17A of the second packing 17, and the seal surface 9a This is an example in which the wall thickness (seal width W2) of the seal surface 9a is made smaller than the rubber width W1 of the motor-side upper end portion 17A by reducing the wall thickness.
[0023]
In this case, even when the entire inner peripheral surface of the motor-side upper end portion 17A is in contact with the inner wall surface 10d of the switch cover 10 (that is, when the protrusion 17b described in the first embodiment is not provided), the second When a tightening force is applied to the packing 17, as shown in FIG. 5, the inner peripheral portion of the motor-side upper end portion 17 </ b> A that does not contact the seal surface 9 a of the terminal case 9 is the inner peripheral wall surface of the terminal case 9 and the inner side of the switch cover 10. It bulges between the wall surface 10d. As a result, the bulging portion can act as a resistance to oppose the force generated at the motor-side upper end portion 17 </ b> A to protrude outward, so that the motor-side upper end portion of the second packing 17 against the seal surface 9 a of the terminal case 9. It is possible to prevent 17A from protruding outward. By applying the configuration of the present embodiment to the first embodiment, the effect of preventing the motor-side upper end portion 17A from protruding can be further improved.
[0024]
(Third embodiment)
In the present embodiment, a protrusion 14a is provided on the inner peripheral surface of the motor-side upper end portion 14A of the first packing 14 (made of rubber) sandwiched between the center case 8 and the terminal case 9, and the protrusion 14a. It is an example which made it contact | abut on the outer peripheral surface of a built-in component.
When the space between the housing 4 and the switch cover 10 is divided into the center case 8 and the terminal case 9, if there is no portion corresponding to the inner wall surface 10 d of the switch cover 10 inside the first packing 14, There is a risk that the packing 14 may fall off inward. Therefore, when dividing into the center case 8 and the terminal case 9, for example, the dividing surface may be set at a position where the outer peripheral surface of a built-in component such as the bobbin 5 can prevent the first packing 14 from falling off.
[0025]
Here, in order to ensure the clearance with the yoke of the starter motor 2, when the case-side wall surface cannot be provided opposite to the outer peripheral surface of the first packing 14, the first packing 14 has the first packing. The configuration of the embodiment can be applied.
In other words, as shown in FIG. 6, the first packing 14 is provided with a protrusion 14 a on the inner peripheral surface of the motor-side upper end portion 14 </ b> A, and the tip of the protrusion 14 a is formed on the outer peripheral surface of the flange portion 5 a of the bobbin 5. It is in contact. In this case, since there is a gap between the inner peripheral surface of the motor-side upper end portion 14A and the outer peripheral surface of the flange portion 5a of the bobbin 5, internal stress generated in the motor-side upper end portion 14A of the first packing 14 is inward. The upper end 14A on the motor side of the first packing 14 can be prevented from protruding outward from the sealing surfaces of the cases 8 and 9.
[0026]
Further, the motor-side upper end portion 14A of the first packing 14 is positioned such that the protrusion 14a provided on the inner peripheral surface thereof is in contact with the outer peripheral surface of the flange portion 5a of the bobbin 5, so that the motor-side upper end portion 14A is It can be prevented from falling inward.
FIG. 6 is a plan view of the state in which the first packing 14 is disposed in the center case 8 as viewed from the axial direction (a state before the terminal case 9 is assembled), and in this drawing, the first packing 14 is shown. Although the wall surface on the case side facing the outer peripheral surface of the terminal case 9 is not shown, the fitting wall portion 9b (see FIG. 3) of the terminal case 9 fitted on the outer periphery of the center case 8 is actually other than the motor-side upper end portion 14A. It is opposed to the outer peripheral surface of the surface with a slight gap.
[Brief description of the drawings]
FIG. 1 is a plan view showing an assembled state of a packing to a switch cover.
FIG. 2 is a half sectional view in the axial direction of the magnet switch (cross sectional view taken along the line BB in FIG. 4).
FIG. 3 is a side view of the starter.
FIG. 4 is a plan view seen from the rear side of the starter.
FIG. 5 is an enlarged view of a packing assembly portion for explaining the operation of the second embodiment.
FIG. 6 is a plan view (as viewed from CC in FIG. 2) showing a state where the packing is assembled to the center case (third embodiment).
FIG. 7 is a plan view showing an example of a conventional product.
FIG. 8 is a diagram for explaining a problem of the prior art.
[Explanation of symbols]
1 Magnet switch 5 Bobbin (built-in parts)
8 Center case (first case)
9 Terminal case (first case or second case)
9a Sealing surface of terminal case 10 Switch cover (second case)
10c Bending part (outer peripheral wall part)
10d inner wall (opposite wall)
14 1st packing 14A The motor side upper end part of a 1st packing (non-regulation part)
14a First packing protrusion 17 Second packing 17A Motor side upper end portion of second packing (non-regulated portion)
17b Second packing protrusion W1 Rubber width W2 Seal width

Claims (3)

A first case and a second case, which are fastened and fixed by bolts with rubber packing interposed therebetween, are included in the first case or the second case except for a part in the circumferential direction. An outer peripheral wall portion facing the outer peripheral surface of the packing is provided,
The packing includes a regulating portion protruding outward is regulated by the outer peripheral wall, as well as organic and non-regulated site which is not regulated by the outer peripheral wall portion, the inner peripheral side of the packing, the entire circumference A magnet switch for starter with a gap across
The packing is provided with a protrusion projecting inwardly on the inner peripheral surface of the non-regulated part, and the protrusion is in contact with an opposing wall surface having a gap on the inner peripheral side of the packing. Magnetic switch for starter, characterized by being arranged . In the starter magnet switch according to claim 1,
In the first case or the second case, the width of the seal surface that contacts the non-regulated portion of the packing is smaller than the width of the non-regulated portion of the packing,
The packing is provided with an inner peripheral end in the width direction of the non-regulated portion that protrudes inward from an inner peripheral end in the width direction of the seal surface that contacts the non-regulated portion . magnetic switch. The starter magnet switch according to claim 1 or 2 ,
The packing is an annular body, the annular body has the non-regulating portion in a part in the circumferential direction, and the protrusion is provided at a substantially central portion in the circumferential direction of the non-regulating portion. Magnet switch for starter.

Images