JP3829613B2 - Starter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a starter for starting an engine.
[0002]
[Prior art]
Conventionally, for example, a deceleration starter as shown in FIG. 6 is known. The starter includes a reduction gear 120 that decelerates the rotation of the armature 100 and transmits the rotation to the pinion shaft 110, and a one-way clutch 130 that transmits the rotation of the pinion shaft 110 to the pinion gear, and the rotation of the pinion shaft 110 and the armature 100. The shaft 101 is provided coaxially.
In this configuration, since the armature 100 and the speed reducer 120 are arranged adjacent to each other in the axial direction, foreign matters such as brush powder generated by the wear of the brush 150 slidingly contacting the commutator 140 enter the speed reducer 120 side. There is a possibility of mixing with grease for lubrication. If the brush powder is mixed into the grease, problems such as abnormal wear of gears used in the reduction gear 120 and sliding failure at the sliding portion occur. Therefore, conventionally, the center housing 160 in which the reduction gear 120 is accommodated A dustproof plate 170 is disposed on the inner side to separate the speed reducer 120 and the armature 100 from each other.
[0003]
[Problems to be solved by the invention]
Since the dust-proof plate 170 is provided for the purpose of preventing foreign matters such as brush powder from entering the speed reduction device 120 side, as shown in FIG. A fitting gap 180 is generated.
By the way, the grease used in the reduction gear 120, the one-way clutch 130, and the like may be vaporized or liquefied due to change with time or high temperature. This grease oil component passes through the fitting gap 180 from the clutch chamber in which the speed reducer 120 is accommodated due to a change in the starter mounting angle, the internal pressure of the starter, etc., and the motor chamber in which the armature 100 is accommodated. And may adhere to the contact portion between the brush 150 and the commutator 140.
[0004]
Further, in a starter (see FIG. 2) in which a magnet switch with a built-in motor contact is disposed behind the pinion shaft, the leg portion 221 of the stationary core 220 is caulked and fixed to the case 210 of the magnet switch 200 as shown in FIG. A gap 230 is formed in the caulking portion. For this reason, the grease oil flows from the clutch chamber into the switch chamber through the gap 230 and adheres to the motor contact composed of the movable contact 250 provided in the plunger 240 and the fixed contact (not shown) fixed to the case 210. there's a possibility that.
As described above, when the grease oil adheres to the electrical contact portion, the brush and the motor contact may be worn early, and there is a possibility that the performance is lowered due to an increase in contact resistance.
The present invention has been made based on the above circumstances, and its object is to prevent or reduce the flow of grease oil to the switch chamber, is to provide a starter capable of suppressing the premature wear of the motor contact point .
[0005]
[Means for Solving the Problems]
(Means of Claim 1)
In a starter in which a starter motor or a magnet switch is assembled adjacent to the clutch mechanism with respect to the housing that houses the clutch mechanism, the magnet switch is assembled adjacent to the clutch mechanism with respect to the housing. It has a switch case that separates and a stationary core that is housed in the switch chamber and forms a fixed magnetic path, and the leg of the stationary core passes through the switch case and is fixed by crimping to the switch case. The generated gap is hermetically closed by a seal member .
This prevents or significantly reduces the grease oil flows into the clutch chamber or Las switch chamber. As a result, the motor contact is accommodated in the switch chamber grease oil can be prevented or significantly reduced from adhering, it is possible to suppress premature wear of the motor contact, and can avoid performance degradation due to increase in contact resistance.
[0008]
(Means of Claim 2 )
The starter according to claim 1, wherein the seal member is made of a resin that cures at normal temperature or high temperature.
[0009]
(Means of claim 3 )
The starter described in claim 1 is characterized in that rubber is used for the seal member.
[0010]
(Means of claim 4 )
In starter according to claim 1, the clutch mechanism is characterized in that it has a reduction gear for decelerating the rotation of the armature.
[0011]
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 sectional view of a magnet switch showing a seal structure of a starter, and FIG. 2 is a half sectional view of the starter.
A starter 1 shown in FIG. 2 includes a starter motor 3 that generates a rotational force in the armature 2, a magnet switch 4 that energizes the armature 2 by closing a built-in motor contact (described below), and a pinion gear 5 on the shaft. A reduction device (described later) that reduces the rotation of the pinion shaft 6 and the armature 2 and transmits it to the pinion shaft 6, a one-way clutch 7 that transmits the rotation of the pinion shaft 6 to the pinion gear 5, a reduction device, and a one-way clutch 7 are housed. The starting motor 3 and the magnet switch 4 are assembled to the front housing 8 in a two-axis configuration.
[0012]
a) The starting motor 3 includes a cylindrical yoke 10 in which the fixed magnetic pole 9 is disposed on the outer periphery of the armature 2, a motor housing 11 that closes the front end opening of the yoke 10, and an end cover that closes the rear end opening of the yoke 10. 12 forms a substantially sealed internal space (referred to as a motor chamber), and the armature 2 and the brush 13 are accommodated in the motor chamber. However, the motor housing 11 is provided integrally with a switch case 16 of the magnet switch 4 described later (see FIG. 1).
The armature 2 is rotatably supported by the motor housing 11 and the end cover 12 via bearings 14 and 15, and when the motor contact of the magnet switch 4 is closed, power is supplied via the brush 13 and rotates in one direction.
[0013]
b) The magnet switch 4 forms a substantially sealed internal space (referred to as a switch chamber) by a switch case 16 and an end plate 17 that closes the rear end opening of the switch case 16, and a coil 18, A stationary core 19, a plunger 20, a motor contact and the like are accommodated (see FIG. 1).
As shown in FIG. 1, the coil 18 includes a known pull-in coil 18a and a holding coil 18b and is wound around a bobbin 21 in a two-layer state. When a starter switch (not shown) is turned on, the coil 18 is supplied with power from the battery and generates a magnetic force in the stationary core 19.
[0014]
The stationary core 19 includes a first core 19A (see FIG. 1) provided in a U-shape and a second core 19B combined with the first core 19A, and both the cores 19A and 19B. Surrounds the coil 18 to form a fixed magnetic path. Further, as shown in FIG. 1, the first core 19A has a pair of leg portions 19a projecting forward (leftward in FIG. 1) from both side ends of the U-shape, and the leg portions 19a. Is inserted through a through hole provided through the end face of the switch case 16, and the tip of the leg portion 19a is caulked and fixed to the switch case 16 (see FIG. 3).
Further, since a minute gap (see FIG. 8) is formed between the leg portion 19a inserted through the through hole of the switch case 16 and the through hole, the gap is formed at the seal member 22 (for example, at normal temperature or high temperature). The resin agent is hardened airtightly (see FIG. 1).
[0015]
The plunger 20 is slidably inserted into the inner periphery of a cylindrical sleeve 23 (see FIG. 1) mounted on the inner periphery of the bobbin 21, and is biased toward the end plate 17 side (right direction in FIG. 1) by a spring (not shown). Has been.
The motor contact is composed of a movable contact 24 provided at the rear end of the plunger 20 and a set of fixed contacts (not shown) fixed to the switch case 16, and the plunger 20 moves to the left in the figure. When the movable contact 24 comes into contact with a set of fixed contacts, the motor contact is closed, and the plunger 20 moves rightward in the figure, and when the movable contact 24 is detached from the set of fixed contacts, the motor contact is opened.
[0016]
In the magnet switch 4, when the coil 18 is energized, the plunger 20 is attracted and moved in the left direction with respect to the magnetized stationary core 19, and when the energization to the coil 18 is stopped, the return spring (not shown) The plunger 20 is pushed back by the urging force to return to the stationary position (position shown in FIG. 1). The movement of the plunger 20 opens and closes the motor contact.
[0017]
c) The pinion shaft 6 is disposed coaxially with the central axis of the plunger 20 in front of the magnet switch 4 and is rotatably supported by the front housing 8 via a pair of bearings 25 and 26. When the plunger 20 of the magnet switch 4 is attracted and moved in the left direction in the figure, the pinion shaft 6 is pushed forward through a rod 27 and a ball 28 connected to the plunger 20, and the pinion gear 5 provided on the shaft. Can be meshed with the ring gear of the engine.
The pinion gear 5 is spline-coupled to the outer periphery of the pinion shaft 6 and is provided so as to be rotatable integrally with the pinion shaft 6.
[0018]
d) As shown in FIG. 2, the reduction gear is configured by a drive gear 29 provided on the rotation shaft 2 a of the armature 2, an idle gear 30 that meshes with the drive gear 29, and a clutch gear 31 that meshes with the idle gear 30. While the rotation of the armature 2 is transmitted from the drive gear 29 to the idle gear 30 to the clutch gear 31, the rotational force is increased. The rotational force of the clutch gear 31 is transmitted to the pinion shaft 6 via the one-way clutch 7 provided on the inner periphery of the clutch gear 31.
e) The front housing 8 forms an attachment portion to the engine, and is combined with the switch case 16 in the axial direction to form a clutch chamber that houses the clutch gear 31 and the one-way clutch 7 of the reduction gear. .
[0019]
Next, the effect of this embodiment will be described.
Note that the operation of the starter 1 is very well known, and a description thereof is omitted here.
The above-described starter 1 is generated in the clutch chamber because the gap formed between the leg portion 19a provided in the first core 19A of the magnet switch 4 and the through hole provided in the switch case 16 is closed by the seal member 22. Thus, it is possible to prevent the grease oil component from flowing into the switch chamber from the clutch chamber through the gap. As a result, it is possible to prevent or significantly reduce the grease oil from adhering to the motor contact (movable contact 24 and fixed contact), so it is possible to suppress early wear of the motor contact and to prevent performance degradation due to increased contact resistance. Is possible.
[0020]
( Reference example )
Next, a reference example according to the present invention will be described.
FIG. 4 is a cross-sectional view of the main part showing the seal structure of the starter 1, and FIG. 5 is a half cross-sectional view of the starter 1.
In the starter 1 of this reference example , as shown in FIG. 5, a pinion shaft 6 and a rotation shaft 2 a of the armature 2 are provided on the same axis, and a reduction gear 32 (planetary gear) is provided between the pinion shaft 6 and the armature 2. A deceleration mechanism) is interposed.
In this configuration, since the armature 2 and the speed reducer 32 are arranged adjacent to each other in the axial direction, the brush powder generated by the wear of the brush 13 may enter the speed reducer 32 side and be mixed into the lubricating grease. There is. Therefore, in order to prevent intrusion of foreign matter such as brush powder, a dust-proof plate 34 is disposed inside the center housing 33 that houses the reduction gear 32, and separates the reduction gear 32 from the armature 2.
[0021]
However, the dust-proof plate 34 is not fitted in close contact with the center housing 33, and a minute fitting gap (see FIG. 7) is generated between the two. Therefore, in this reference example , as shown in FIG. 4, an O-ring 35 is attached to the outer diameter surface of the dust-proof plate 34 so as to hermetically close the fitting gap. Accordingly, it is possible to prevent the grease oil from flowing into the motor chamber through the fitting gap from the clutch chamber (in this case, formed by the center housing 33) in which the reduction gear 32 is accommodated. It is possible to prevent or greatly reduce the oil component from adhering to the contact portion between the brush 13 and the commutator 36, and to avoid the commutation deterioration due to the adhesion of the grease oil component. As a result, it is possible to suppress early wear of the brush 13 and to prevent performance degradation due to an increase in contact resistance.
[0022]
In the first embodiment, as the sealing member 22 of the present invention, a resin agent that cures at room temperature or high temperature is used, and in the reference example , an O-ring 35 is used. It goes without saying that a suitable sealing means can be selected and used.
In the first embodiment and the reference example described above that although the starter 1 equipped with a respective speed reduction equipment, construction of the present invention, without having a reduction equipment, directly pinion shaft rotation of the armature It can also be applied to a starter that transmits. In this case, it is possible to prevent the grease oil generated in the clutch chamber that houses the one-way clutch from flowing into the switch chamber or the motor chamber.
[Brief description of the drawings]
FIG. 1 is a sectional view of a magnet switch showing a seal structure of a starter (first embodiment).
FIG. 2 is a half sectional view of a starter (first embodiment).
FIG. 3 is a view on A in FIG. 2;
FIG. 4 is a cross-sectional view of an essential part showing a seal structure of a starter ( reference example ).
FIG. 5 is a half sectional view of a starter ( reference example ).
FIG. 6 is a half sectional view of a starter (prior art).
FIG. 7 is a cross-sectional view showing a seal structure of a starter (prior art).
FIG. 8 is a cross-sectional view showing a structural gap generated in the starter (prior art).
[Explanation of symbols]
1 Starter 2 Armature 3 Starter Motor 4 Magnet Switch 5 Pinion Gear 8 Front Housing (Housing)
16 Switch Case 19 Stationary Core 19a Stationary Core Leg 22 Seal Member 24 Movable Contact (Motor Contact)
32 Reduction gear ( reference example )
33 Center housing (housing : reference example )
34 Dust-proof plate ( reference example )
35 O-ring ( reference example )

Claims (4)

A starter motor that houses an armature in a motor chamber formed therein, and generates a rotational force in the armature;
A magnet switch that houses a motor contact in a switch chamber formed inside, opens and closes the motor contact, and pushes the pinion gear toward the ring gear side of the engine using electromagnetic force generated when the motor contact is closed;
A clutch mechanism provided in a torque transmission path through which rotation of the armature is transmitted to the pinion gear;
A clutch chamber is formed therein, and the clutch chamber includes a housing that houses the clutch mechanism;
In the starter in which the starting motor or the magnet switch is assembled adjacent to the clutch mechanism with respect to the housing,
The magnet switch is assembled to the housing adjacent to the clutch mechanism, and includes a switch case that separates the clutch chamber and the switch chamber, and a stationary core that is housed in the switch chamber and forms a fixed magnetic path. The starter is characterized in that a leg portion of the stationary core passes through the switch case and is caulked and fixed to the switch case, and a gap generated in the caulking portion is hermetically closed by a seal member . The starter according to claim 1 ,
The seal member is made of a resin that cures at room temperature or high temperature. The starter according to claim 1 ,
The starter characterized in that rubber is used for the seal member. In starter according to claim 1,
The starter characterized in that the clutch mechanism has a speed reducer that decelerates the rotation of the armature.

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