JP2016121779A - Drive plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability of a ring gear part of a drive plate.SOLUTION: A drive plate 1 connected to a crank shaft of an engine and a fluid transmittance device includes a ring gear part 3 engaged with a pinion gear 51 that is a spur gear rotationally driven by a motor of an engine starting device for starting an engine. When the engine starts, the ring gear part 3 is driven by the motor and rotates in one direction, a tooth trace of each of the teeth 30 of the ring gear part 3 is inclined in the same direction as that of the tooth trace of each of the teeth 51t of the pinion gear 51 inclined in respect to a shaft center SC of the ring gear part 3 by a reaction force from the ring gear part 3 rotated in one direction and a twisting angle α of each of the teeth 30 of the ring gear part 3 is set to be equal to or more than 0.2°.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a drive plate that is connected to a crankshaft of an engine and a power transmission target and is rotated in one direction by a motor of an engine starter when the engine is started.

  2. Description of the Related Art Conventionally, an engine starter is known that includes a ring gear connected to an engine crankshaft and a pinion gear connected to a starter motor. The engine starter engages the ring gear by jumping into the ring gear when the engine is started ( For example, see Patent Document 1). In this engine starting device, both the ring gear and the pinion gear are configured as bevel gears. Then, the twisting directions of the teeth of the ring gear and the pinion gear are set so that the thrust force in the jumping direction acts on the pinion gear in a state where the pinion gear drives the ring gear. As described above, the engine starter employs the inclined gears as the ring gear and the pinion gear, thereby reducing the noise (gear noise) at the time of starting the engine.

JP 2002-130097 A

  However, when the engine is started, a reaction force acts on the pinion gear of the engine starter from a ring gear that is driven by the starter motor and rotates in one direction in a direction opposite to the one direction. May tilt with respect to the axis of the ring gear. When such an inclination of the pinion gear occurs, the teeth of the pinion gear and the teeth of the ring gear locally hit, and a large stress is locally generated on the ring gear. Further, in a vehicle equipped with a so-called idling stop system, the number of engine starts is greatly increased. Therefore, further improvement in durability is required for the ring gear connected to the crankshaft of the engine.

  Therefore, the main object of the present invention is to further improve the durability of the ring gear portion of the drive plate.

  A drive plate according to the present invention includes a plate portion connected to an engine crankshaft and a power transmission target, and a ring gear portion meshed with a pinion gear that is a spur gear that is rotationally driven by a motor of an engine starter that starts the engine. In the drive plate that is rotated in one direction by the motor when the engine is started, the tooth streaks of the teeth of the ring gear portion are reaction forces from the ring gear portion that are driven by the motor and rotate in the one direction. Is inclined in the same direction as the teeth of each tooth of the pinion gear inclined with respect to the axis of the ring gear portion, and the twist angle α of each tooth of the ring gear portion is 0.2 ° or more. And

  This drive plate includes a plate portion connected to the crankshaft of the engine and a power transmission target, and a ring gear portion that meshes with a pinion gear of an engine starter configured as a spur gear. Further, the tooth streaks of the teeth of the ring gear portion are in the same direction as the tooth streaks of the teeth of the pinion gear that is inclined with respect to the axis of the ring gear portion by a reaction force from the ring gear portion that is driven by the motor and rotates in one direction. It is inclined to. And the torsion angle α of each tooth of the ring gear portion is set to 0.2 ° or more. That is, in this drive plate, each tooth of the ring gear portion is an inclined tooth inclined at a very small torsion angle in the same direction as the tooth trace of each tooth of the pinion gear inclined with respect to the axis of the ring gear portion by the reaction force. It is formed. Thus, when the engine is started, even if the pinion gear is inclined with respect to the axis of the ring gear portion by the reaction force from the ring gear portion that is driven by the motor and rotates in one direction, the teeth of the pinion gear and the teeth of the ring gear portion are It can suppress hitting locally. As a result, it is possible to further improve the durability of the ring gear portion by preventing a large stress from being locally generated in the ring gear portion when the engine is started.

It is a top view which shows the drive plate which concerns on one Embodiment of this invention. It is sectional drawing along the II-II line of FIG. It is a schematic block diagram of the engine starting device used with the drive plate shown in FIG. 1 and FIG. FIG. 3 is a schematic diagram for explaining a configuration of a ring gear portion of the drive plate shown in FIGS. 1 and 2. It is a schematic diagram for demonstrating the experiment and analysis result performed in order to determine the torsion angle of each tooth | gear of a ring gear part.

  Next, the form for implementing this invention is demonstrated, referring drawings.

  FIG. 1 is a plan view showing a drive plate 1 according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line II-II in FIG. A drive plate 1 shown in these drawings transmits power output from an engine (internal combustion engine) (not shown) as a prime mover mounted on a vehicle to a fluid transmission device (not shown) such as a torque converter or a fluid coupling as a power transmission target. It is used for As shown in the figure, the drive plate 1 includes a plate portion 2 connected to an engine crankshaft and a fluid transmission device, and a pinion gear 51 of an engine starter (starter) 50 for cranking and starting the engine (see FIG. 2). And an annular ring gear portion 3 that can be engaged with each other.

  The plate portion 2 of the drive plate 1 is formed by pressing a flexible plate material (metal plate) such as a cold rolled steel plate. As shown in the figure, the plate portion 2 includes a flat annular first connecting portion 20 formed in the center portion, an annular second connecting portion 24 connected to the first connecting portion 20 via a bent portion 23, and a first 2 It has the short cylindrical part 27 extended in the axial direction of the drive plate 1 (plate part 2) from the outer periphery of the connection part 24. As shown in FIG.

  A center hole 21 is formed in the first connecting portion 20 so as to be located at the center thereof, and a plurality of (for example, eight in the present embodiment) first connecting holes (e.g., eight in this embodiment) are provided around the center hole 21. Fastening holes) 22 are arranged at equal intervals. The second connecting portion 24 includes a plurality (for example, six in this embodiment) of second connecting holes (fastening holes) 25 and a plurality of (for example, six in this embodiment) light holes 26. Are formed at regular intervals in the circumferential direction (60 ° intervals in the present embodiment). The cylindrical portion 27 is formed by, for example, pressing so as to extend in a cantilevered manner from the outer periphery of the second connecting portion 24 (plate portion 2).

  The ring gear portion 3 includes a plurality of teeth (external teeth) 30 that each include a tooth surface formed by, for example, an involute curve and a substantially flat tooth tip surface and can mesh with the teeth of the pinion gear 51. The ring gear portion 3 is manufactured separately from the plate portion 2 using, for example, existing ring gear manufacturing equipment, and is joined to the outer peripheral surface of the cylindrical portion 27 of the plate portion 2 by welding. As a result, the ring gear portion 3 extends in the axial direction of the drive plate 1 on the outer peripheral side of the plate portion 2. In addition, the ring gear part 3 is not restricted to the thing separate from the plate part 2, For example, you may shape | mold integrally with the plate part 2 by press work etc.

  The crankshaft of the engine and the first connecting portion 20 of the plate portion 2 are fastened to each other by a bolt inserted into each first connecting hole 22. Further, the end surface of the set block 5 fixed to the fluid transmission device from the end surface side of the cylindrical portion 27 is brought into contact with the second connecting portion 24 of the plate portion 2 so as to cover the second connecting hole 25, The two connecting portions 24 and the set block 5 are fastened to each other by bolts inserted through the second connecting holes 25. As a result, the engine and the fluid transmission device are connected via the drive plate 1, and the power output from the engine can be transmitted to the fluid transmission device that is the target of power transmission. Further, the engine can be cranked and started by operating the engine starting device 50 in a state where the pinion gear 51 and the ring gear portion 3 are engaged with each other.

  FIG. 3 is a schematic configuration diagram showing the engine starting device 50. As shown in the figure, in addition to the pinion gear 51, the engine starter 50 includes a motor M, a pinion shaft 52, a speed reduction mechanism 53, and a drive shaft 55 connected to the rotation shaft of the motor M via a one-way clutch 54. And a case 57 for housing the motor M, the pinion shaft 52, the speed reduction mechanism 53, the one-way clutch 54, the pinion extrusion solenoid 56, and the like. The pinion gear 51 is configured as a spur gear, and each tooth of the pinion gear 51 has a tooth line extending in parallel with the axis. Note that the speed reduction mechanism 53 may be omitted from the engine starting device 50.

  The pinion shaft 52 has a center hole portion into which at least one end is opened and the drive shaft 55 is inserted, and a male helical spline formed on the outer peripheral surface of the drive shaft 55 is formed on the inner peripheral surface of the pinion shaft 52. A meshing female helical spline is formed. As a result, the pinion shaft 52 is coupled to the drive shaft 55 inserted in the center hole portion so as to be integrally rotatable and movable in the axial direction. The pinion shaft 52 is supported by a case 57 via a bearing 58 so as to be rotatable and movable in the axial direction, and the free end portion of the pinion shaft 52 protrudes from the case 57 to the outside. The pinion gear 51 is fixed to the free end portion of the pinion shaft 52 protruding from the case 57. Further, the pinion shaft 52 is connected to the plunger of the pinion push-out solenoid 56 via the shift lever 59. Thereby, by supplying electric power to the electromagnetic part of the pinion push-out solenoid 56, the pinion gear 51 and the ring gear part 3 are engaged with each other from the retracted position shown in FIG. 3, as indicated by the white arrow in FIG. It can be moved in the axial direction to the meshing position.

  In addition, the case 57 includes, for example, a flange-shaped attachment portion 57a that is fastened (fixed) to a case support portion 60 provided on a vehicle body of the vehicle on which the engine starter 50 is mounted or a transmission case of the transmission of the vehicle. Have. The case 57 is attached to the vehicle body or the transmission case so that the shaft centers of the pinion shaft 52 and the drive shaft 55 extend parallel to the drive plate 1, that is, the shaft center SC (see FIG. 2) of the ring gear portion 3. As a result, the pinion gear 51 and the pinion shaft 52 are supported in a cantilever manner by the vehicle body or the transmission case via the case 57. In the present embodiment, as shown in FIG. 2, the engine starter 50 is a case where the pinion gear 51 moves from the fluid transmission device side (transmission side) toward the drive plate 1 (engine side) when starting the engine. It is attached to the support part 60. However, the engine starting device 50 may be arranged so that the pinion gear 51 moves from the engine side toward the drive plate 1 (fluid transmission device side) when starting the engine.

  As shown in FIG. 3, the bearing 58 is disposed between the inner race 58i that slidably supports the outer peripheral surface of the pinion shaft 52, the outer race supported by the case 57, and the inner race 58i and the outer race. A ball bearing having a plurality of balls. In the present embodiment, the bearing 58 is disposed in the case 57 so as to be closer to the pinion gear 51 (the free end portion of the pinion shaft 52) than the mounting portion 57a and the case support portion 60. A boundary (portion A in FIG. 3) between the inner race 58i of the bearing 58 and the pinion shaft 52 on the pinion gear side is located between the case support portion 60 and the pinion gear 51 in the axial direction of the pinion shaft 52.

  Next, the configuration of the ring gear portion 3 of the drive plate 1 will be described in detail.

  When the engine is started, the drive plate 1 is driven by the motor M of the engine starter 50 to rotate in one direction, and the pinion gear 51 has a ring gear portion 3 that rotates in one direction as indicated by a broken line arrow in FIG. Therefore, a reaction force opposite to the one direction acts. Therefore, at the time of engine start (during cranking), as shown in FIG. 4, the pinion gear 51 acts on the original shaft center, that is, the shaft center SC of the ring gear portion 3 (drive plate 1) by the action of the reaction force. There is a risk of tilting.

  In particular, in the engine starting device 50 described above, the pinion gear 51 and the pinion shaft 52 are supported in a cantilevered manner by the vehicle body or the transmission case, and therefore the pinion gear 51 is caused to react with the axial center SC of the ring gear portion 3 by the reaction force from the ring gear portion 3. It becomes easier to tilt. That is, in the engine starting device 50, when the reaction force from the ring gear portion 3 acts on the pinion gear 51, the pinion shaft 52 is a boundary between the inner race 58i of the bearing 58 on the pinion gear 51 side and the pinion shaft 52 (A in FIG. 3). In addition, the case 57 of the engine starting device 50 is inclined with respect to the boundary (B portion in FIG. 3) between the case support portion 60 and the mounting portion 57a, and therefore the inclination of the pinion gear 51 (tooth trace). Tends to be large.

  Based on this, in the drive plate 1 of the present embodiment, as shown in FIG. 4, the tooth streaks of the teeth 30 of the ring gear portion 3 are driven by the motor M of the engine starter 50 and rotate in one direction. The reaction force from the ring gear portion 3 of the plate 1 is slightly inclined in the same direction as the teeth of each tooth 51t of the pinion gear 51 inclined with respect to the axis SC of the ring gear portion 3. That is, in the drive plate 1, each tooth 30 of the ring gear portion 3 has a very small twist angle in the same direction as the tooth trace of each tooth 51 t of the pinion gear 51 inclined with respect to the axis SC of the ring gear portion 3 due to the reaction force. It is formed as an inclined tooth inclined at α. As shown in FIG. 4, when the tooth line of each tooth 51 t of the pinion gear 51 inclined with respect to the axis SC of the ring gear portion 3 due to the reaction force from the ring gear portion 3 becomes right-handed, the ring gear portion 3 The twist direction of each tooth 30 is also a right twist.

  Further, the present inventors set the pinion gear with respect to the axis SC of the ring gear portion 3 when the drive plate 1 is rotated in one direction by being driven by the motor M in order to determine the torsion angle α of each tooth 30 of the ring gear portion 3. The inclination angle β (see FIG. 4) of the tooth traces of the 51 teeth 51t was measured. In measuring the inclination angle β, the edge portions 51a and 51b at both ends in the axial direction of the teeth 51t of the pinion gear 51 were used as measurement points. Further, in a state where the pinion gear 51 and the ring gear portion 3 are engaged with each other (a state where the pinion gear 51 is jumped into the ring gear portion 3), no torque is transmitted from the pinion gear 51 to the ring gear portion 3 (no load state). The positions of the edge portions 51a and 51b were set to zero points. Further, the positions of the edge portions 51a and 51b at the timing at which the torque transmitted from the pinion gear 51 to the ring gear portion 3 becomes maximum (near the engine top dead center) are measured, and the measured values and the edge portions 51a and 51b at the zero point are measured. The inclination angle β of the streak of each tooth 51t was calculated from the difference from the position 51b. As a result, it has been found that the inclination angle β in the drive plate 1 and the engine starting device 50 is included in the range of 0.4 ° to 0.6 °.

  Based on such measurement results, the present inventors set 0.5 °, which is the median value of the above range, as the reference angle, and the manufacturing tolerance of the ring gear portion 3 is ± 0.3 °. The torsion angle α of each tooth 30 is set to 0.2 ° or more and 0.8 ° or less. Furthermore, the present inventors conducted experiments and analyzes in order to verify the validity of the range of the twist angle α of 0.2 ° or more and 0.8 ° or less. As a result, when the torsion angle α is less than 0.2 °, when the engine is started, as shown in FIG. 5A, for example, the fluid transmission device side (intrusion) in the axial direction of the teeth 30 of the ring gear portion 3 It was found that the end of the side (the lower side in the figure) hits the tooth surface of the tooth 51t of the pinion gear 51 locally (substantially makes point contact). When the torsion angle α is 0.8 ° or more, as shown in FIG. 5B, when starting the engine, for example, the engine side in the axial direction of the teeth 51t of the pinion gear 51 (anti-dive side: FIG. It has been found that the end portion on the middle upper side locally hits the tooth surface of the tooth 30 of the ring gear portion 3.

  On the other hand, when the twist angle α of each tooth 30 of the ring gear portion 3 is not less than 0.2 ° and not more than 0.8 °, the teeth 30 of the ring gear portion 3 are connected to the teeth of the pinion gear 51 when the engine is started. As shown in FIG. 5C, it was found that the tooth surface of the tooth 30 and the tooth surface of the tooth 51t can be brought into contact with each other in a wide range. Based on the results of such experiments and analysis, the drive plate 1 in which the teeth of each tooth 51t of the pinion gear 51 are inclined by about 0.4 ° to 0.6 ° with respect to the axis SC of the ring gear portion 3 when the engine is started, and In the engine starting device 50, the twist angle α of each tooth 30 of the ring gear portion 3 is set to 0.2 ° or more and 0.8 ° or less.

  Thereby, in the drive plate 1 used together with the engine starting device 50, when the engine is started, the pinion gear 51 is brought into the axial center SC of the ring gear portion 3 by the reaction force from the ring gear portion 3 that is driven by the motor M and rotates in one direction. Even if it inclines with respect to it, it can suppress that the tooth | gear 51t of the pinion gear 51 and the tooth | gear 30 of the ring gear part 3 contact | win locally. As a result, it is possible to ensure extremely good durability of the ring gear portion 3 by preventing a large stress from being locally generated in the ring gear portion 3 when the engine is started.

  Further, if the drive plate 1 configured as described above is used together with the engine starter 50 in which the pinion gear 51 is supported in a cantilever manner, the pinion shaft 52 (and the drive shaft 55) of the pinion shaft 51 is suppressed in order to suppress the inclination of the pinion gear 51. Since it is not necessary to increase the outer diameter or to increase the size of the support structure (such as the case support portion 60) of the engine starter 50, the increase in size of the engine starter 50, the vehicle, or the transmission (transmission case) is suppressed. It becomes possible. However, it goes without saying that the drive plate 1 described above may be combined with an engine starter that supports the pinion gear 51 in a both-sided manner.

  In the drive plate 1 used together with the engine starting device 50, it is possible to satisfactorily prevent the teeth 51t of the pinion gear 51 and the teeth 30 of the ring gear portion 3 from hitting locally by increasing the torsion angle α. However, it is not necessarily limited to this. That is, depending on the specifications of the drive plate and the engine starting device, the torsion angle α of each tooth 30 of the ring gear portion 3 may be set to 0.8 ° or more.

  As can be seen from the above description, the torsion angle α of each tooth 30 of the ring gear portion 3 and the inclination angle β of each tooth 51t (tooth line) of the pinion gear 51 with respect to the axis SC of the ring gear portion 3 when the engine is started. And the torsion angle α of each tooth 30 of the ring gear portion 3 only needs to coincide with the inclination angle β of each tooth 51t to some extent. That is, the direction of the tooth trace of each tooth 30 of the ring gear portion 3 only needs to substantially coincide with the direction of the tooth trace of each tooth 51t of the pinion gear 51 inclined when the engine is started.

  As described above, the drive plate according to the present invention includes the plate portion connected to the engine crankshaft and the power transmission target, and the pinion gear that is a spur gear that is rotationally driven by the motor of the engine starter that starts the engine. A drive plate that is rotated in one direction by the motor when the engine is started, and each tooth of the ring gear portion is driven by the motor and rotates in the one direction. The reaction force from the ring gear portion is inclined in the same direction as the teeth of each tooth of the pinion gear that is inclined with respect to the axis of the ring gear portion, and the twist angle α of each tooth of the ring gear portion is 0.2 °. It is the above.

  This drive plate includes a plate portion connected to the crankshaft of the engine and a power transmission target, and a ring gear portion that meshes with a pinion gear of an engine starter configured as a spur gear. Further, the tooth streaks of the teeth of the ring gear portion are in the same direction as the tooth streaks of the teeth of the pinion gear that is inclined with respect to the axis of the ring gear portion by a reaction force from the ring gear portion that is driven by the motor and rotates in one direction. It is inclined to. And the torsion angle α of each tooth of the ring gear portion is set to 0.2 ° or more. That is, in this drive plate, each tooth of the ring gear portion is an inclined tooth inclined at a very small torsion angle in the same direction as the tooth trace of each tooth of the pinion gear inclined with respect to the axis of the ring gear portion by the reaction force. It is formed. Thus, when the engine is started, even if the pinion gear is inclined with respect to the axis of the ring gear portion by the reaction force from the ring gear portion that is driven by the motor and rotates in one direction, the teeth of the pinion gear and the teeth of the ring gear portion are It can suppress hitting locally. As a result, it is possible to further improve the durability of the ring gear portion by preventing a large stress from being locally generated in the ring gear portion when the engine is started.

  “Same direction” means only that the twist angle α of each tooth of the ring gear part and the inclination angle of each tooth (tooth line) of the pinion gear with respect to the axis of the ring gear at the time of starting the engine are completely the same. This also means that the torsion angle α of each tooth of the ring gear portion and the inclination angle of each tooth of the pinion gear coincide to some extent. That is, the direction of the tooth trace of each tooth of the ring gear portion may be substantially the same as the direction of the tooth trace of each tooth of the pinion gear inclined when the engine is started. Further, the ring gear portion may be a separate member from the plate portion joined to the plate portion, and may be formed integrally with the plate portion by, for example, press molding.

  Further, the twist angle α of each tooth of the ring gear portion may be 0.8 ° or less. As a result, it is possible to satisfactorily prevent the pinion gear teeth and the ring gear teeth from hitting locally by increasing the torsion angle α too much.

  Furthermore, the inclination angle β of the teeth of each pinion gear with respect to the axis of the ring gear portion when the ring gear portion is driven by the motor and rotates in the one direction is 0.4 ° or more and 0.6 It may be less than °. Thus, when the pinion gear is inclined by about 0.4 ° to 0.6 ° with respect to the axis of the ring gear portion due to the reaction force from the ring gear portion, the torsion angle α of each tooth of the ring gear portion is set to 0.2. By setting the angle to be not less than 0 ° and not more than 0.8 °, the durability of the ring gear portion can be ensured extremely well.

  The pinion gear may be fixed to a free end portion of a pinion shaft that is rotationally driven by the motor. When the pinion gear is fixed to the free end portion of the pinion shaft in this way, the pinion gear is supported in a cantilevered manner, so that the pinion gear is driven by the motor and rotated in one direction by the reaction force from the ring gear portion. It becomes easier to tilt with respect to the axis of the part. Therefore, if the drive plate as described above is used together with an engine starter in which the pinion gear is supported in a cantilever manner, the outer diameter of the pinion shaft or the like is increased in order to suppress the inclination of the pinion gear, or the support structure for the engine starter Since it is not necessary to increase the size of the engine, it is possible to suppress the increase in size of the engine starter and the like.

  Furthermore, the engine starter may include a case that houses the motor and has a mounting portion that is attached to a case support provided in a vehicle body of a vehicle on which the engine is mounted or a transmission case of the transmission. The pinion shaft may be rotatably supported by the case via a bearing, and the boundary between the inner race of the bearing and the pinion shaft on the pinion gear side is the pinion shaft between the case support portion and the pinion gear. May be located in the axial direction. In the engine starter configured as described above, when the reaction force from the ring gear portion acts on the pinion gear, the pinion shaft tilts around the boundary between the inner race of the bearing and the pinion shaft on the pinion gear side, and the case further The inclination of the pinion gear tends to increase because the transmission case tilts with the boundary between the case support portion and the attachment portion as a base point. Therefore, if the drive plate described above is used together with such an engine starter, it is not necessary to increase the outer diameter of the pinion shaft or increase the size of the support structure of the engine starter in order to suppress the inclination of the pinion gear. An increase in size of the starter, the vehicle, or the transmission (transmission case) can be suppressed.

  And this invention is not limited to the said embodiment at all, and it cannot be overemphasized that a various change can be made within the range of the extension of this invention. Furthermore, the mode for carrying out the invention described above is merely a specific embodiment of the invention described in the column for solving the problem, and is described in the column for means for solving the problem. It is not intended to limit the elements of the invention.

  The present invention can be used in the manufacturing industry of a drive plate that transmits power from an engine to a power transmission target.

  DESCRIPTION OF SYMBOLS 1 Drive plate, 2 Plate part, 3 Ring gear part, 5 Set block, 20 1st connection part, 21 Center hole, 22 1st connection hole, 23 Bending part, 24 2nd connection part, 25 2nd connection hole, 26 Light Hole, 27 Cylindrical part, 30, 51t teeth, 50 Engine starter, 51 Pinion gear, 51a, 51b Edge part, 52 Pinion shaft, 53 Reduction mechanism, 54 One-way clutch, 55 Drive shaft, 56 Pinion extrusion solenoid, 57 Case 57a mounting portion, 58 bearing, 58i inner race, 59 shift lever, 60 case support, M motor, SC axis.

Claims (5)

An engine crankshaft and a plate connected to a power transmission target; and a ring gear that meshes with a pinion gear that is a spur gear that is rotationally driven by a motor of an engine starter that starts the engine. In the drive plate rotated in one direction by the motor,
The tooth lines of the teeth of the ring gear portion are tooth lines of the teeth of the pinion gear that are inclined with respect to the axis of the ring gear portion by a reaction force from the ring gear portion that is driven by the motor and rotates in the one direction. Tilted in the same direction as
The drive plate according to claim 1, wherein a twist angle α of each tooth of the ring gear portion is 0.2 ° or more. The drive plate according to claim 1,
The drive plate according to claim 1, wherein a twist angle α of each tooth of the ring gear portion is 0.8 ° or less. The drive plate according to claim 2,
The inclination angle β of the teeth of each tooth of the pinion gear with respect to the axial center of the ring gear portion when the ring gear portion is driven by the motor and rotates in the one direction is 0.4 ° or more and 0.6 ° or less. The drive plate characterized by being. The drive plate according to any one of claims 1 to 3,
The drive plate, wherein the pinion gear is fixed to a free end portion of a pinion shaft that is rotationally driven by the motor. The drive plate according to claim 4,
The engine starter is
Including a case that houses the motor and has an attachment portion that is attached to a case support portion provided in a vehicle body of a vehicle on which the engine is mounted or a transmission case of a transmission,
The pinion shaft is rotatably supported by the case via a bearing,
A drive plate, wherein a boundary between the inner race of the bearing and the pinion shaft on the pinion gear side is located between the case support portion and the pinion gear in the axial direction of the pinion shaft.

Images