JP2009114860A - Starter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a starter capable of suppressing an outflow of grease employed for a shock absorbing unit 9 from a case by centrifugal force and of maintaining stable shock absorbing performance. <P>SOLUTION: A shock absorbing unit 9 has an axial gap A formed between an outer periphery of a ring drive 45 and an outer periphery of a ring spacer 47 and a radial gap B formed between the outer periphery of the ring spacer 47 and an outer periphery of a ring drive 46, respectively. With this configuration, even if grease flows out toward the axial gap A from a damper space by centrifugal force, the grease can be prevented from being scattered to the outside of the shock absorbing unit 9 through the axial gap A since the radial outside of the axial gap A is covered with an outer peripheral wall 47a of the ring spacer 47. As a result, an elastic member 48 is smoothly deflexed in response to relative rotation of the ring drives 45, 46, so that stable shock absorbing performance can be maintained. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a starter including an impact absorbing device that reduces an impact input from an engine side via a pinion gear.

As a prior art, a starter described in Patent Document 1 is known.
As shown in FIG. 7, the starter includes an output shaft 100 that is driven and rotated by a motor (not shown), a pinion gear 120 that is fitted to the outer periphery of the output shaft 100 via a bearing 110, and the output shaft 100. And an impact absorbing device 130 provided between the pinion gear 120 and the pinion gear 120. The shock absorbing device 130 includes a first case 140 that is spline-fitted to the outer periphery of a cylindrical portion provided integrally with the pinion gear 120, a second case 150 that is spline-fitted to the outer periphery of the output shaft 100, and both cases 140. , 150 and an intermediate case 160 disposed so as to be relatively rotatable, and a rubber damper 170 or the like incorporated between the cases 140 to 160, for example, when receiving an impact from the engine side during cranking, the intermediate case The first case 140 and the second case 150 rotate relative to 160, and the rubber damper 170 has a function of reducing impact by compressing and deforming in the circumferential direction.
JP 2006-207573 A

  As a procedure for assembling the starter provided with the shock absorbing device 130 described above, first, the shock absorbing device 130 and the pinion gear 120 are fitted into the output shaft 100, and then a pinion stopper 180 for preventing the pinion gear 120 from coming off from the output shaft 100 is provided. After fitting into the output shaft 100, the C-ring 200 is fitted into the circumferential groove 190 formed in the output shaft 100 with the pinion stopper 180 moved to the axial motor side (rightward in FIG. 7). Thereafter, the pinion stopper 180 is moved to the opposite side of the motor in the axial direction and is locked to the C ring 200.

  Here, the shock absorbing device 130 bends between the first case 140 and the second case 150 in the axial direction in order to move the pinion stopper 180 toward the motor in the axial direction (first case 140). Need to be pushed into the second case 150 side). Therefore, predetermined gaps are secured between the first case 140 and the intermediate case 160 and between the intermediate case 160 and the second case 150, respectively. That is, the pinion stopper 180 can be moved to the motor side in the axial direction by bending the shock absorbing device 130 in the axial direction by the gap set between the cases.

By the way, in the shock absorbing device 130, grease is applied to the sliding surfaces of the rubber damper 170 and the cases 140 to 160. This is to improve the slidability of the rubber damper 170 with the grease, and when the impact is applied, the rubber damper 170 is smoothly bent to efficiently reduce the generated impact.
However, as described above, in the shock absorber 130, gaps are formed between the first case 140 and the intermediate case 160 and between the intermediate case 160 and the second case 150. Grease may flow out from this gap due to centrifugal force. When a large amount of grease flows out, it is difficult for the rubber damper 170 to bend smoothly, and there is a concern that the performance of the shock absorbing device 130 may deteriorate. For this reason, it is necessary to take a large amount of the initial amount of grease in anticipation of the outflow of the grease, which causes an increase in cost.

  The present invention has been made based on the above circumstances, and its purpose is to provide a starter capable of suppressing the grease used in the shock absorbing device from flowing out of the case by centrifugal force and maintaining stable shock absorbing performance. It is to provide.

(Invention of Claim 1)
The starter of the present invention is arranged such that a motor that generates a rotational force, an output shaft that rotates when the rotational force of the motor is transmitted, and an outer periphery of the output shaft are disposed so as to be relatively rotatable via a bearing, and a motor is generated. A pinion gear that transmits rotational force to the ring gear of the engine, and an impact absorbing device that is disposed on the outer periphery of the output shaft and reduces the impact force by compressive deformation of the elastic member when an impact force is applied to the pinion gear from the engine side, The shock absorbing device has a first case coupled to the pinion gear and a second case coupled to the output shaft, and an elastic member is incorporated between the first case and the second case. In addition, the first case and the second case are disposed so as to be relatively rotatable via the elastic member, and the first case and the second case are axially disposed between the outer peripheral portion of the first case and the outer peripheral portion of the second case. Clearance and diameter Wherein the the gap direction is provided continuously.

  The impact absorbing device rotates with the output shaft when the rotational force of the motor is transmitted and the output shaft rotates. Therefore, the impact absorbing device slides inside the first case and the second case (especially when the elastic member is bent). The grease applied to the sliding surface of the case is going to move to the outer circumference in the radial direction by centrifugal force. On the other hand, in the present invention, the axial gap and the radial gap are continuously provided between the outer periphery of the first case and the outer periphery of the second case. It is possible to prevent the grease from splashing directly from the gap to the outside of both cases, and to prevent the grease from flowing out from the inside of both cases. As a result, the grease applied to the inside of the shock absorbing device can be held for a long period of time, so that when the shock is received from the engine side, the elastic member is moved according to the relative rotation between the first case and the second case. It can bend smoothly and maintain a stable shock absorbing capacity.

  In addition, since the shock absorbing device of the present invention has an axial gap between the outer peripheral portion of the first case and the outer peripheral portion of the second case, the conventional starter described in Patent Document 1 Similarly, when the C-ring is fitted into the peripheral groove of the output shaft, the impact absorbing device can be bent by the axial gap by pushing the first case into the second case. As a result, the starter assembling step according to the present invention (after the impact absorbing device and the pinion gear are fitted to the output shaft, the C ring is fitted to the peripheral groove of the output groove, and the pinion stopper is locked to the C ring. Step) can be performed in the same manner as a conventional starter.

(Invention of Claim 2)
The starter of the present invention is arranged such that a motor that generates a rotational force, an output shaft that rotates when the rotational force of the motor is transmitted, and an outer periphery of the output shaft are disposed so as to be relatively rotatable via a bearing, and a motor is generated. A pinion gear that transmits rotational force to the ring gear of the engine, and an impact absorbing device that is disposed on the outer periphery of the output shaft and reduces the impact force by compressive deformation of the elastic member when an impact force is applied to the pinion gear from the engine side, The shock absorber includes a first case coupled to the pinion gear, a second case coupled to the output shaft, and at least one intermediate disposed between the first case and the second case. And an elastic member is incorporated in series between the first case and the second case via the intermediate case, and the first case and the intermediate case are interposed via the elastic member. And the intermediate case and the second case are disposed so as to be relatively rotatable, and between the outer periphery of the first case and the outer periphery of the intermediate case, and between the outer periphery of the intermediate case and the second case. A gap in the axial direction and a gap in the radial direction are respectively provided between the outer peripheral portion and the outer peripheral portion.

  The impact absorbing device rotates with the output shaft when the rotational force of the motor is transmitted and the output shaft rotates, so the inside of the first case, the intermediate case, and the second case (especially the elastic member bends). The grease applied to the sliding surface of the sliding case tends to move to the outer circumference in the radial direction by centrifugal force. On the other hand, in the present invention, axial gaps are provided between the outer peripheral portion of the first case and the outer peripheral portion of the intermediate case, and between the outer peripheral portion of the intermediate case and the outer peripheral portion of the second case. And the radial gap are continuously provided, it is possible to prevent the grease from splashing directly from the axial gap to the outside of each case, and to suppress the grease from flowing out from the inside of each case. As a result, the grease applied to the inside of the shock absorbing device can be held for a long period of time, so that when the shock is received from the engine side, the elastic member is moved according to the relative rotation between the first case and the second case. It can bend smoothly and maintain a stable shock absorbing capacity.

  Further, the shock absorbing device of the present invention has axial directions between the outer periphery of the first case and the outer periphery of the intermediate case, and between the outer periphery of the intermediate case and the outer periphery of the second case, respectively. As in the conventional starter described in Patent Document 1, when the C-ring is fitted into the peripheral groove of the output shaft, the first case is pushed into the second case side, The shock absorbing device can be bent by the gap in the axial direction. As a result, the starter assembling step according to the present invention (after the impact absorbing device and the pinion gear are fitted to the output shaft, the C ring is fitted to the peripheral groove of the output groove, and the pinion stopper is locked to the C ring. Step) can be performed in the same manner as a conventional starter.

(Invention of Claim 3)
The starter according to claim 1 or 2, wherein axial gaps and radial gaps are alternately and continuously formed in a maze shape.
In the starter according to claim 1, since the gap provided between the outer peripheral portion of the first case and the outer peripheral portion of the second case is formed in a labyrinth shape (labyrinth shape), the outflow of grease due to centrifugal force The effect which can suppress is improved. Similarly, the starter described in claim 2 is provided between the outer peripheral portion of the first case and the outer peripheral portion of the intermediate case, and between the outer peripheral portion of the intermediate case and the outer peripheral portion of the second case. Since the gap is formed in a maze shape (labyrinth shape), the effect of suppressing the outflow of grease due to centrifugal force is improved.

(Invention of Claim 4)
The starter according to any one of claims 1 to 3, wherein the radial gap is set smaller than the axial gap.
As described in the prior art of Patent Document 1, when assembling the starter, in order to attach the pinion stopper to the output shaft, the shock absorbing device is bent in the axial direction (the first case is moved to the second case side). Need to push in). Therefore, in the starter described in claim 1, the axial gap provided between the outer periphery of the first case and the outer periphery of the second case, the starter described in claim 2, An axial gap is required between the outer peripheral portion of the case and the outer peripheral portion of the intermediate case, and between the outer peripheral portion of the intermediate case and the outer peripheral portion of the second case. That is, it is necessary to ensure an axial clearance necessary for attaching the pinion stopper. On the other hand, since the gap in the radial direction is not involved in assembling the starter, it can be set small enough that the case does not interfere with the case. As a result, the effect of suppressing the outflow of grease is enhanced, and the grease retention performance is further improved.

(Invention of Claim 5)
The starter of the present invention is arranged such that a motor that generates a rotational force, an output shaft that rotates when the rotational force of the motor is transmitted, and an outer periphery of the output shaft are disposed so as to be relatively rotatable via a bearing, and a motor is generated. A pinion gear that transmits rotational force to the ring gear of the engine, and an impact absorbing device that is disposed on the outer periphery of the output shaft and reduces the impact force by compressive deformation of the elastic member when an impact force is applied to the pinion gear from the engine side, The shock absorbing device has a first case coupled to the pinion gear and a second case coupled to the output shaft, and an elastic member is incorporated between the first case and the second case. In addition, the first case and the second case are disposed so as to be relatively rotatable via the elastic member, and at least one of the first case and the second case has an elastic portion. Characterized in that it is concave formed on the sliding surface which slides upon flexing.

  According to said structure, it is possible to hold | maintain grease in the recessed part formed in the sliding surface of a case. In addition, the grease held in the recess can suppress the grease from moving to the outer periphery by the wall surface that forms the outer periphery of the recess when the shock absorbing device rotates and centrifugal force acts on the grease. It can be held effectively. As a result, the grease applied to the inside of the shock absorbing device can be prevented from flowing out, so that when receiving an impact from the engine side, the elastic member smoothly moves according to the relative rotation between the first case and the second case. It can bend and maintain a stable shock absorbing capacity.

(Invention of Claim 6)
The starter of the present invention is arranged such that a motor that generates a rotational force, an output shaft that rotates when the rotational force of the motor is transmitted, and an outer periphery of the output shaft are disposed so as to be relatively rotatable via a bearing, and a motor is generated. A pinion gear that transmits rotational force to the ring gear of the engine, and an impact absorbing device that is disposed on the outer periphery of the output shaft and reduces the impact force by compressive deformation of the elastic member when an impact force is applied to the pinion gear from the engine side, The shock absorber includes a first case coupled to the pinion gear, a second case coupled to the output shaft, and at least one intermediate disposed between the first case and the second case. And an elastic member is incorporated in series between the first case and the second case via the intermediate case, and the first case and the intermediate case are interposed via the elastic member. The intermediate case and the second case are arranged so as to be relatively rotatable, and at least one of the first case and the intermediate case slides when the elastic member is bent. A concave portion is formed in at least one of the intermediate case and the second case, and a concave portion is formed on a sliding surface that slides when the elastic member bends.

  According to said structure, it is possible to hold | maintain grease in the recessed part formed in the sliding surface of a case. In addition, the grease held in the recess can suppress the grease from moving to the outer periphery by the wall surface that forms the outer periphery of the recess when the shock absorbing device rotates and centrifugal force acts on the grease. It can be held effectively. As a result, the grease applied to the inside of the shock absorbing device can be prevented from flowing out, so that when receiving an impact from the engine side, the elastic member smoothly moves according to the relative rotation between the first case and the second case. It can bend and maintain a stable shock absorbing capacity.

(Invention of Claim 7)
6. The starter according to claim 5, wherein an axial gap and a radial gap are continuously provided between the outer periphery of the first case and the outer periphery of the second case. To do.
In this case, by combining the effect of the invention described in claim 1 and the effect of the invention described in claim 5, the effect of suppressing the outflow of grease is further increased, and a more stable shock absorbing ability is obtained. Can do.

(Invention of Claim 8)
The starter according to claim 6, wherein the first case has an axial direction between the outer peripheral portion of the first case and the outer peripheral portion of the intermediate case, and the outer peripheral portion of the intermediate case and the outer peripheral portion of the second case. A gap and a radial gap are provided continuously.
In this case, by combining the effect of the invention described in claim 2 and the effect of the invention described in claim 6, the effect of suppressing the outflow of grease is further increased, and a more stable shock absorbing ability is obtained. Can do.

(Invention of Claim 9)
The starter according to any one of claims 5 to 8, wherein the concave portion is formed in an arc shape along a circumferential direction in a radial center portion of the sliding surface.
When the concave portion formed on the sliding surface of the case is formed so as to deviate from the radial central portion of the sliding surface and deviate to one side of the radial direction, the elastic member There is a possibility that a part of the hook is caught in the recess and cannot be smoothly bent. Therefore, by forming the concave portion in the central portion in the radial direction of the sliding surface, it is possible to slide smoothly without impairing the slidability of the elastic member.
Further, by forming the concave portion in an arc shape along the circumferential direction of the sliding surface, the grease held in the concave portion can be effectively supplied between the sliding surface of the case and the elastic member.

(Invention of Claim 10)
The starter according to any one of claims 5 to 9, wherein a radial dimension of the concave portion is ½ or less of a radial dimension of the elastic member.
If the radial dimension of the recess is too large relative to the elastic member, when the elastic member bends due to an impact, a part of the elastic member may be caught in the recess and cannot be bent smoothly. Therefore, by setting the radial dimension of the concave portion to ½ or less of the radial dimension of the elastic member, it is possible to smoothly slide without impairing the slidability of the elastic member.

(Invention of Claim 11)
The starter according to any one of claims 1 to 10, wherein the pinion gear is always meshed with the ring gear.
When the starter pinion gear is always meshed with the ring gear on the engine side, not only the impact that occurs when the engine starts, that is, the impact that occurs when the pinion gear hits the ring gear due to fluctuations in the engine speed during cranking, the engine rotates in reverse. When, for example, the reverse rotation due to the swing of the crankshaft that occurs when the engine is stopped, or when the vehicle reverses due to an engine stall on the climbing road, the reverse rotation impacts the pinion gear that is always meshed with the ring gear. As transmitted. For this reason, in a starter in which the pinion gear always meshes with the ring gear, the impact absorbing device has a large function to absorb the impact received from the engine side.

(Invention of Claim 12)
The starter according to claim 11 is used in an engine automatic stop / restart system that automatically controls stop and restart of the engine.
An automatic engine stop / restart system (generally also called an idle stop system, an eco-run system, etc.), for example, automatically stops the engine when the vehicle stops temporarily at an intersection or traffic jam, and then starts a predetermined start by the driver. When the operation is performed, the engine is automatically restarted, which is effective for improving the fuel consumption of the vehicle or improving the exhaust emission. In a vehicle equipped with this automatic engine stop / restart system, the number of engine starts, that is, the number of starter starts inevitably increases compared to a vehicle not equipped with the system.

By the way, when the engine is started (during cranking), the hitting sound generated when the pinion gear hits the ring gear due to engine rotation fluctuation becomes unpleasant noise for the user.
For this reason, in a vehicle equipped with the above system, unpleasant noise and impact are generated each time the engine is restarted. On the other hand, the starter of the present invention can reduce the impact and unpleasant noise generated at the start of the engine by the impact absorbing device. There is an effect that can be reduced.

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

FIG. 1 is a half sectional view of the starter 1, and FIG. 2 is a half sectional view showing the configuration of the shock absorbing device 9 and its periphery.
As shown in FIG. 1, a starter 1 according to the first embodiment includes a motor 2 that generates a rotational force in an armature 2a, and a main circuit that is provided in a motor circuit for energizing the armature 2a from a battery (not shown). An electromagnetic relay 3 that opens and closes contacts (described later), a reverse rotation prevention clutch 4 that prevents reverse rotation of the armature 2a, a speed reducer 5 that decelerates rotation of the armature 2a, and a motor 2 via the speed reducer 5 The output shaft 6 to which the drive torque is transmitted, the pinion gear 8 fitted to the outer periphery of the output shaft 6 via the bearing 7, the impact absorbing device 9 disposed on the outer periphery of the output shaft 6, and the like. Note that the starter 1 of this embodiment can be used in an engine automatic stop / restart system that automatically controls stop and restart of the engine.

The motor 2 is provided with a commutator 10 on one end side (right side in the drawing) of the armature shaft 2b that outputs the rotation of the armature 2a, and the armature 2a is connected to the armature 2a via a brush 11 disposed on the outer periphery of the commutator 10. It is a known commutator motor that is energized. The armature shaft 2b has one end protruding from the commutator 10 and is rotatably supported by the end frame 13 via the bearing 12, and the end on the counter-commutator side (the other end) is connected to the output shaft 6. It is inserted in the inner periphery of the cavity part formed in the edge part of this through the bearing 14 (refer FIG. 2) so that relative rotation is possible.
The end frame 13 is fitted and assembled to the end side opening of the yoke 15 forming the magnetic circuit of the motor 2, and a plurality of through bolts (not shown) are fastened and fixed to the starter housing 16.

The electromagnetic relay 3 includes a solenoid incorporating the electromagnetic coil 17 and the plunger 18, and a resin contact cover 19 fixed to the solenoid, and a main contact is disposed inside the contact cover 19.
The solenoid has a known function of attracting the plunger 18 by forming an electromagnet by energizing the electromagnetic coil 17, and closes the main contact in conjunction with the movement of the plunger 18. When the energization of the electromagnetic coil 17 is stopped and the attraction force of the electromagnet disappears, the reaction force stored in the return spring 20 causes the plunger 18 to be pushed back to the left in the figure to open the main contact.

  The main contact is connected to the B potential contact (battery side) of the motor circuit via the B terminal bolt 21 and to the low potential side (motor side) of the motor circuit via the M terminal bolt 23. The M fixed contact 24 and the movable contact 25 which are movable integrally with the plunger 18 and intermittently connect between the two fixed contacts 22, 24 are formed. The main contact is closed when the fixed contacts 22 and 24 are conducted, and the main contact is opened when the movable contact 25 is separated from the fixed contacts 22 and 24 and the conduction between the fixed contacts 22 and 24 is interrupted. It becomes a state.

  Each of the B terminal bolt 21 and the M terminal bolt 23 is fixed to the contact cover 19, and a battery cable (not shown) is connected to the distal end side of the B terminal bolt 21 protruding in the axial direction (right direction in the drawing) from the contact cover 19. Similarly, the terminal of the motor lead wire 26 is connected to the tip side of the M terminal bolt 23 protruding in the axial direction from the contact cover 19. The motor-side end of the motor lead wire 26 is drawn into the motor 2 through a rubber grommet 27 sandwiched between the yoke 15 and the end frame 13, and is electrically connected to the brush 11 on the positive electrode side. It is connected to the.

The reverse rotation prevention clutch 4 includes an inner 28 provided on a part of the armature shaft 2b, an outer 29 that forms a plurality of cam chambers (not shown) between the inner peripheral surface of the inner 28, and a cam chamber. It is comprised from the roller 30 etc. which are arrange | positioned.
The outer 29 has an outer wall portion 29a extending outward in the radial direction. An outer peripheral portion of the outer wall portion 29a is sandwiched between the yoke 15 and the spacer member 31 and is positioned in the axial direction. The rotation is restricted with respect to the housing 16. The cam chamber is formed in a wedge shape in which the space for accommodating the roller 30 is gradually narrowed in the counter-rotating direction of the armature shaft 2b.

The roller 30 is biased by a spring (not shown) in a narrowing direction (a counter-rotating direction of the armature shaft 2b) in which the space of the cam chamber is narrowed, and has a function of intermittently transmitting torque between the inner 28 and the outer 29. .
The reverse rotation prevention clutch 4 is reversely rotated in the engine, and the reverse rotation is input to the starter 1, and the reverse rotation of the pinion gear 8 → the shock absorbing device 9 → the output shaft 6 → the speed reducer 5 → the armature shaft 2 b. Is transmitted, the roller 30 moves in the narrowing direction of the cam chamber and is locked between the inner 28 and the outer 29 to prevent the armature 2a from rotating backward.
On the other hand, when the engine is driven by the starter 1, the roller 30 moves in the anti-narrow direction (direction in which the space becomes wider) of the cam chamber, which is the rotation direction of the armature shaft 2b, and idles, whereby the armature shaft 2b. Allow rotation of

The speed reducer 5 is a planetary gear speed reducer that can be decelerated coaxially with the armature shaft 2b, and is rotationally restricted via a sun gear 32 formed on the non-commutator side of the armature shaft 2b and a torque limiter described below. The internal gear 33 (see FIG. 2) and a plurality of planetary gears 34 (see FIG. 2) meshing with both gears 32 and 33, and the revolving motion of the planetary gear 34 is transmitted to the output shaft 6.
As shown in FIG. 2, the torque limiter includes a fixed disk 36 whose rotation is restricted by a center case 35, a rotating disk 37 whose rotation is restricted by a frictional force between the fixed disk 36 and the center case 35, and a center case. When the excessive torque exceeding the sliding torque of the rotating disk 37 is applied to the internal gear 33, the rotating disk 37 is sandwiched between the rotating disk 37 and the fixed disk 36. When 37 slides (rotates) against the frictional force, the internal gear 33 is allowed to rotate and the transmission of excessive torque is interrupted.

The center case 35 is disposed inside the starter housing 16 at right angles to the output shaft 6, abuts against a step provided on the inner periphery of the starter housing 16, is positioned in the axial direction, and rotates with respect to the starter housing 16. It is regulated.
The output shaft 6 is disposed on the same axis as the armature shaft 2b, and the end on the side opposite to the motor is rotatably supported by the tip of the starter housing 16 via the bearing 39, and the end on the motor side is It is connected to the speed reducer 5 and is rotatably supported by the center case 35 via a bearing 40 (see FIG. 2).
The pinion gear 8 is always meshed with the ring gear 41 on the engine side, and is connected to the output shaft 6 via an impact absorbing device 9 described below. The pinion gear 8 is in contact with a pinion stopper 43 assembled to the end of the output shaft 6 via a C ring 42 and is prevented from coming off from the output shaft 6. The C ring 42 is fitted in a circumferential groove 44 formed on the outer periphery of the output shaft 6.

Next, the impact absorbing device 9 according to the present invention will be described with reference to FIGS.
The shock absorbing device 9 includes a ring drive 45 that is a first case of the present invention, a ring drive 46 that is a second case of the present invention, a ring space 47 that is an intermediate case of the present invention, and a ring drive 45. And an elastic member 48 incorporated between the ring space 47 and the ring drive 46.
As shown in FIG. 2, the ring drive 45 is provided with a cylindrical boss portion 45 a at the center portion in the radial direction, and this boss portion 45 a is splined to the outer periphery of the cylindrical portion 8 a provided integrally with the pinion gear 8. The pinion gear 8 is connected so as not to rotate relative to the pinion gear 8.

As with the ring drive 45, the ring drive 46 is provided with a cylindrical boss portion 46 a at the center in the radial direction, and this boss portion 46 a is spline-fitted to the outer periphery of the output shaft 6 to They are connected so that they cannot rotate relative to each other.
The ring space 47 is disposed between the ring drive 45 and the ring drive 46 and is rotatably fitted to the outer periphery of a boss portion 46 a provided in the ring drive 46.
Between the ring drive 45 and the ring space 47 facing each other in the axial direction, and between the ring space 47 and the ring drive 46, damper spaces S (see FIG. 3) for housing the elastic members 48 are respectively provided. A plurality of locations (for example, 3 locations) are formed in the circumferential direction. The ring drive 45 and the ring drive 46 are made of metal (for example, iron) in order to ensure the strength necessary for torque transmission, and the ring space 47 is made of resin that can contribute to weight reduction, for example. good.

As shown in FIG. 3, the elastic member 48 is provided with a block-shaped main mass portion 48a and a sub-mass portion 48c connected to the main mass portion 48a via a bridging portion 48b. It is integrally molded with rubber. One elastic member 48 is housed in each of three damper spaces S formed between the ring drive 45 and the ring space 47, and similarly formed between the ring space 47 and the ring drive 46. One each is stored in three damper spaces S.
Inside the shock absorbing device 9, a ring drive 45, a ring space 47, a surface of the elastic member 48 and a damper space S are formed so that the elastic member 48 can bend smoothly when an impact is applied. In addition, grease for lubrication is applied to each surface of the ring drive 46.

The ring drive 45 and the ring space 47 adjacent to each other in the axial direction are provided so as to be relatively rotatable via the elastic member 48 in a state in which the elastic member 48 is incorporated therebetween. Similarly, the ring space 47 and the ring drive 46 are provided so as to be relatively rotatable via the elastic member 48 in a state in which the elastic member 48 is incorporated therebetween.
Further, as shown in FIG. 4, the outer periphery of the ring drive 45 and the outer periphery of the ring space 47, and the outer periphery of the ring space 47 and the outer periphery of the ring drive 46, as shown in FIG. A gap B is provided.

Here, the gap A in the axial direction and the gap B in the radial direction will be specifically described with reference to FIG.
The ring drive 45 and the ring space 47 are provided with opposing wall surfaces that are opposed to each other in the axial direction at a predetermined interval outside the damper space S formed therebetween. The predetermined interval formed in the above is referred to as an axial gap A. In addition, a ring-shaped outer peripheral wall 47 a extending from the opposing wall surface to the axially opposite motor side (the left side in the drawing) is provided at the outer diameter portion of the ring space 47, and the inner diameter of the outer peripheral wall 47 a is the outer diameter of the ring drive 45. A larger gap B is formed between the inner periphery of the outer peripheral wall 47 a and the outer periphery of the ring drive 45. That is, the axial gap A and the radial gap B are formed in an L shape.

Similarly, the ring space 47 and the ring drive 46 are provided with opposing wall surfaces facing each other in the axial direction with a predetermined interval outside the damper space S formed between them. A predetermined interval formed between the wall surfaces is referred to as an axial gap A. Further, a ring-shaped outer peripheral wall 47 a extending from the opposing wall surface to the axial motor side (right side in the drawing) is provided at the outer diameter portion of the ring space 47. A large gap B is formed between the inner periphery of the outer peripheral wall 47 a and the outer periphery of the ring drive 46. That is, the axial gap A and the radial gap B are formed in an L shape.
The axial gap A has a required dimension so that the C-ring 42 can be fitted into the circumferential groove 44 formed in the output shaft 6 and the pinion stopper 43 can be assembled via the C-ring 42. Has been. The radial gap B is set smaller than the axial gap A. Preferably, the ring drive 45 and the ring space 47 and the ring space 47 and the ring drive 46 are desirably formed so small that they do not interfere with each other (not contact when rotated relative to each other).

Next, the operation of the starter 1 will be described.
When the main contact of the motor circuit is closed by the electromagnetic relay 3, the armature 2a is energized from the battery to generate a rotational force on the armature 2a. The rotation of the armature 2 a is decelerated by the speed reducer 5 and transmitted to the output shaft 6, and further transmitted from the output shaft 6 to the pinion gear 8 via the shock absorbing device 9, and the rotation of the pinion gear 8 is transmitted to the ring gear 41. And crank the engine.
When the engine completes explosion and the engine speed exceeds the starter speed, for example, a one-way clutch (not shown) built in the ring gear 41 idles and torque is generated between the engine crankshaft and the ring gear 41. Therefore, the rotation of the engine is not transmitted to the pinion gear 8, and overrun of the armature 2a can be prevented.

  Further, when the engine rotates reversely, for example, when the engine rotates reversely when the vehicle moves backward due to crankshaft swinging when the engine stops, or when the vehicle moves backward due to an engine stall, the ring gear 41 The one-way clutch built in is engaged. Therefore, in the starter 1 in which the pinion gear 8 is always meshed with the ring gear 41, the reverse rotation of the engine is transmitted from the ring gear 41 to the pinion gear 8. On the other hand, since the starter 1 of the present embodiment includes the reverse rotation prevention clutch 4 that can prevent the reverse rotation of the armature 2a, even when the reverse rotation of the engine is input to the starter 1, the reverse of the armature 2a. Rotation can be prevented.

In the above operation, the impact absorbing device 9 is used when the starter 1 receives an impact from the engine side (for example, when the ring gear 41 strikes the pinion gear 8 during cranking or when the engine rotates in the reverse direction). The ring drive 45 and the ring drive 46 rotate relative to each other through the ring space 47 and the elastic member 48 bends (compresses and deforms) in the circumferential direction, thereby reducing the impact force. Have.
The torque limiter rotates when an excessive impact that cannot be absorbed by the impact absorbing device 9, that is, an excessive impact that exceeds the torque limiter set torque (sliding torque of the rotating disk 37) is transmitted to the output shaft 6. When the disk 37 slides against the frictional force, it has a function of blocking the transmission of the impact force. Thereby, an excessive impact is not applied to the torque transmission path of the starter 1, and damage due to the impact received from the engine side can be avoided.

(Effect of Example 1)
The shock absorbing device 9 used in the starter 1 of this embodiment is applied to the inside of the shock absorbing device 9 because it rotates together with the output shaft 6 when the rotational force of the motor 2 is transmitted and the output shaft 6 rotates. Grease tends to move to the outer circumference in the radial direction due to centrifugal force.
On the other hand, between the outer periphery of the ring drive 45 and the outer periphery of the ring space 47, and between the outer periphery of the ring space 47 and the outer periphery of the ring drive 46, the axial gap A and the radial direction, respectively. Since the gap B is continuously provided in an L shape, the outflow of grease due to centrifugal force can be effectively suppressed.

  Specifically, even if grease flows out from the damper space S to the axial gap A due to centrifugal force, the outer circumferential wall 47a of the ring space 47 covers the radially outer side of the axial gap A. It is possible to prevent the grease from splashing outside the shock absorber 9 through the gap A. Further, since the radial gap B is set smaller than the axial gap A, the effect of suppressing the outflow of grease is enhanced. As a result, the grease applied to the inside of the impact absorbing device 9 can be held for a long period of time, so that when the impact is received from the engine side, the elastic member 48 is in accordance with the relative rotation between the ring drive 45 and the ring drive 46. It can bend smoothly and maintain a stable shock absorbing capacity.

  Further, the impact absorbing device 9 of the present embodiment is provided between the outer periphery of the ring drive 45 and the outer periphery of the ring space 47, and between the outer periphery of the ring space 47 and the outer periphery of the ring drive 46, respectively. Since the axial gap A is provided, when the C ring 42 is fitted into the circumferential groove 44 of the output shaft 6, the ring drive 45 is pushed into the ring drive 46 side, and the impact absorbing device 9 is pushed by the axial gap. Can be bent. Thereby, the assembly process of the starter 1 (after the impact absorbing device 9 and the pinion gear 8 are fitted into the output shaft 6, the C ring 42 is fitted into the circumferential groove 44 of the output shaft 6, and the pinion stopper 43 is fitted into the C ring 42. Can be performed in the same manner as the starter described in Patent Document 1.

FIG. 5 is a plan view of the ring space 47.
As shown in FIGS. 5 and 6, the shock absorbing device 9 according to the second embodiment has a recess 49 formed on the inner wall surface (hereinafter referred to as a sliding surface) of the damper space S formed in the ring space 47. ing. Similar to the ring space 47, a recess 49 can be formed on the sliding surface of the ring drive 45 or the ring space 47.
As shown in FIG. 5, the concave portion 49 is formed in an arc shape along the circumferential direction in the radial center portion of the sliding surface. Further, the radial dimension of the recess 49 is set to ½ or less of the radial dimension of the elastic member 48.

  According to the configuration of the present embodiment, the grease can be held in the concave portion 49 formed on the sliding surface of the damper space S. The grease held in the concave portion 49 is moved to the outer peripheral side by the wall surface (step surface on the radially outer side) that forms the outer periphery of the concave portion 49 when the shock absorbing device 9 rotates and centrifugal force acts on the grease. The movement can be suppressed, and the grease can be effectively retained in the recess 49. As a result, since the grease applied to the inside of the shock absorbing device 9 can be prevented from flowing out, the elastic member 48 smoothly moves according to the relative rotation between the ring drive 45 and the ring drive 46 when receiving an impact from the engine side. It can bend and maintain a stable shock absorbing capacity.

In addition, the concave portion 49 is formed in the radial center portion of the sliding surface, and the radial dimension of the concave portion 49 is set to ½ or less of the radial dimension of the elastic member 48. When the elastic member 48 is bent, a part of the elastic member 48 is not caught by the concave portion 49, and the movement of the elastic member 48 is not hindered. That is, the grease can be held in the recess 49 while ensuring the slidability of the elastic member 48. Further, by forming the concave portion 49 in an arc shape along the circumferential direction of the sliding surface, the grease held in the concave portion 49 can be effectively supplied between the sliding surface of the case and the elastic member 48. As a result, the slidability of the elastic member 48 is not impaired when receiving an impact from the engine side, and the ability to retain grease is also improved, so that stable shock absorbing performance can be maintained for a long time. Is possible.
In addition, it is possible to more reliably suppress the outflow of grease by combining the configuration described in the second embodiment (the concave portion 49 is formed on the sliding surface) with the configuration of the first embodiment.

(Modification)
In the impact absorbing device 9 described in the first embodiment, a ring space 47 is arranged between the ring drive 45 and the ring drive 46, and two elastic members 48 are connected in series through the ring space 47 (total of six members). However, it is also possible to increase the number of ring spaces 47 and arrange the elastic members 48 in three or more stages in series. Alternatively, the ring space 47 may be eliminated, and the elastic member 48 may be disposed between the ring drive 45 and the ring drive 46. In this case, it goes without saying that an axial gap A and a radial gap B are formed between the outer periphery of the ring drive 45 and the outer periphery of the ring drive 46.

In the impact absorbing device 9 described in the first embodiment, an example in which the axial gap A and the radial gap B are continuously formed in an L shape is described. However, the axial gap A and the radial direction are described. These gaps B may be alternately and continuously formed in a maze shape (labyrinth shape).
In the starter 1 described in the first embodiment, the pinion gear 8 is always meshed with the ring gear 41. However, the shock absorbing device 9 of the present invention pushes the pinion gear 8 in the counter-motor direction when the engine is started and meshes with the ring gear 41. Also, the present invention can be applied to a starter in which the pinion gear 8 is detached from the ring gear 41 after the engine is started.

(Example 1) which is sectional drawing of a starter. (Example 1) which is a semi-sectional view which shows the structure of an impact-absorbing device and its periphery. (Example 1) which is a top view of the ring space which accommodates an elastic member. (Example 1) which is an expanded sectional view which shows the clearance gap between shock absorbers. (Example 2) which is a top view of a ring space. (Example 2) which is CC sectional drawing of the ring space shown in FIG. It is a half sectional view of an impact absorbing device showing the prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Starter 2 Motor 6 Output shaft 7 Bearing 8 Pinion gear 9 Shock absorber 37 Rotating disk 41 Ring gear 45 Ring drive (first case)
46 Ring drive (second case)
47 Ring space (intermediate case)
48 Elastic member 49 Recess A Axial clearance B Radial clearance

Claims (12)

A motor that generates rotational force;
An output shaft that rotates when the rotational force of the motor is transmitted;
A pinion gear disposed on the outer periphery of the output shaft so as to be relatively rotatable via a bearing, and transmitting a rotational force generated by the motor to an engine ring gear;
In a starter provided with an impact absorbing device that is disposed on the outer periphery of the output shaft and reduces the impact force by compressive deformation of an elastic member when an impact force is applied to the pinion gear from the engine side,
The shock absorber is
A first case connected to the pinion gear; and a second case connected to the output shaft; and the elastic member is incorporated between the first case and the second case. The first case and the second case are disposed so as to be relatively rotatable via the elastic member, and between the outer peripheral portion of the first case and the outer peripheral portion of the second case. A starter characterized in that an axial gap and a radial gap are provided continuously. A motor that generates rotational force;
An output shaft that rotates when the rotational force of the motor is transmitted;
A pinion gear disposed on the outer periphery of the output shaft so as to be relatively rotatable via a bearing, and transmitting a rotational force generated by the motor to an engine ring gear;
In a starter provided with an impact absorbing device that is disposed on the outer periphery of the output shaft and reduces the impact force by compressive deformation of an elastic member when an impact force is applied to the pinion gear from the engine side,
The shock absorber is
A first case coupled to the pinion gear; a second case coupled to the output shaft; and at least one intermediate case disposed between the first case and the second case; And the elastic member is incorporated in series between the first case and the second case via the intermediate case, and the first case and the intermediate case are interposed via the elastic member. The intermediate case and the second case are disposed so as to be relatively rotatable, and between the outer peripheral portion of the first case and the outer peripheral portion of the intermediate case, and the outer peripheral portion of the intermediate case And an outer peripheral portion of the second case, an axial gap and a radial gap are provided continuously, respectively. The starter according to claim 1 or 2,
The starter characterized in that the axial gap and the radial gap are alternately and continuously formed in a maze shape. The starter according to any one of claims 1 to 3,
The starter characterized in that the radial gap is set smaller than the axial gap. A motor that generates rotational force;
An output shaft that rotates when the rotational force of the motor is transmitted;
A pinion gear disposed on the outer periphery of the output shaft so as to be relatively rotatable via a bearing, and transmitting a rotational force generated by the motor to an engine ring gear;
A pinion gear disposed on the outer periphery of the output shaft so as to be relatively rotatable via a bearing, and transmitting a rotational force generated by the motor to an engine ring gear;
In a starter provided with an impact absorbing device that is disposed on the outer periphery of the output shaft and reduces the impact force by compressive deformation of an elastic member when an impact force is applied to the pinion gear from the engine side,
The shock absorber is
A first case connected to the pinion gear; and a second case connected to the output shaft; and the elastic member is incorporated between the first case and the second case. The first case and the second case are arranged to be relatively rotatable via the elastic member, and at least one of the first case and the second case has the A starter, wherein a recess is formed on a sliding surface that slides when the elastic member bends. A motor that generates rotational force;
An output shaft that rotates when the rotational force of the motor is transmitted;
A pinion gear disposed on the outer periphery of the output shaft so as to be relatively rotatable via a bearing, and transmitting a rotational force generated by the motor to an engine ring gear;
In a starter provided with an impact absorbing device that is disposed on the outer periphery of the output shaft and reduces the impact force by compressive deformation of an elastic member when an impact force is applied to the pinion gear from the engine side,
The shock absorber is
A first case coupled to the pinion gear; a second case coupled to the output shaft; and at least one intermediate case disposed between the first case and the second case; And the elastic member is incorporated in series between the first case and the second case via the intermediate case, and the first case and the intermediate case are interposed via the elastic member. The intermediate case and the second case are disposed so as to be relatively rotatable, and at least one of the first case and the intermediate case is slid when the elastic member is bent. A concave portion is formed on the moving sliding surface, and at least one of the intermediate case and the second case has a concave portion on the sliding surface that slides when the elastic member is bent. It is characterized by that Over data. The starter according to claim 5, wherein
A starter characterized in that an axial gap and a radial gap are continuously provided between the outer periphery of the first case and the outer periphery of the second case. The starter according to claim 6, wherein
Between the outer peripheral part of the first case and the outer peripheral part of the intermediate case, and between the outer peripheral part of the intermediate case and the outer peripheral part of the second case, respectively, an axial gap and a radial direction are respectively provided. A starter characterized in that a gap is provided continuously. The starter according to any one of claims 5 to 8,
The said recessed part is formed in circular arc shape along the circumferential direction at the radial direction center part of the said sliding surface, The starter characterized by the above-mentioned. The starter according to any one of claims 5 to 9,
The starter according to claim 1, wherein a radial dimension of the concave portion is ½ or less of a radial dimension of the elastic member. In any starter according to claim 1-10,
The starter characterized in that the pinion gear is always meshed with the ring gear. The starter according to claim 11, wherein
A starter used for an engine automatic stop / restart system for automatically controlling stop and restart of the engine.

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