Engine starter

Patent metadata

Field	Value
Publication number	US-9249770-B2
Application number	US-201113877303-A
Country	US
Kind code	B2
Filing date	Jul 27, 2011
Priority date	Aug 20, 2010
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

The engine starter includes: a starter motor; a pinion unit ( 30 ) for sliding in an axial direction on an output shaft of the starter motor; and a ring gear ( 100 ) which meshes with a pinion pushed out by a push-out mechanism ( 60 ) and receives a transmission of a rotational force of the starter motor to thereby start an engine, and the pinion portion ( 30 ) includes a pinion gear divided in the axial direction into two pinion gears which are a first pinion gear ( 35 ) having a protruded shape for synchronization, for first colliding with the ring gear upon start of meshing with the ring gear, and a second pinion gear ( 34 ) for serving to transmit the rotational force after the meshing.

First claim

The invention claimed is:

1. An engine starter, comprising:
a starter motor;
a pinion unit coupled to an output-shaft side of the starter motor by means of a spline, for sliding in an axial direction;
a ring gear, which has a push-out mechanism for moving the pinion unit to an engaging position with the ring gear, meshes with a pinion of the pinion unit pushed out by the push-out mechanism, and receives a transmission of a rotation force of the starter motor to thereby start an engine,
wherein the pinion unit includes a pinion gear divided in the axial direction into two pinion gears, which are a first pinion gear having a protruded shape for synchronization, for first colliding with the ring gear upon start of meshing with the ring gear, and a second pinion gear for transmitting the rotation force after the meshing,
wherein the protruded shape for synchronization of the first pinion gear is constituted by the same number of protrusions as a number of teeth of the second pinion gear, and an area of a vertical cross section in the axial direction of the protrusion is configured to be smaller than a surface area of the second pinion gear,
wherein the first pinion gear has a configuration for moving in the axial direction independently of the pinion unit, and
wherein the second pinion gear is positioned on a shaft of the pinion unit via the first pinion gear, in the axial direction of the pinion unit, by being pressed in a push-out direction by a spring, and is movable in the axial direction as a result of contraction of the spring.

2. The engine starter according to claim 1 , wherein the protruded shape for synchronization of the first pinion gear is configured to have the same number of teeth as the number of teeth of the second pinion gear.

3. The engine starter according to claim 2 , wherein, in a specification of the tooth of the first pinion gear, a profile shift, a tooth tip outer diameter, or a pressure angle of the second pinion gear is changed to increase a backlash with respect to the ring gear.

4. The engine starter according to claim 1 , wherein the protruded shape for synchronization of the first pinion gear does not have a surface that generates a force of an axial-direction component of the pinion unit in response to a collision in a rotation direction of the ring gear other than a machined surface of a tooth-tip-outer-diameter edge portion and an end surface.

5. The engine starter according to claim 1 , wherein the first pinion gear has a backlash in a rotation direction with respect to a shaft of the pinion unit.

6. The engine starter according to claim 5 , wherein a range in which the first pinion gear is operable as a result of the backlash in the rotation direction is a range in which, after the second pinion gear meshes with the ring gear, a rotation torque force by the first pinion gear is not transmitted to the ring gear.

7. The engine starter according to claim 6 , wherein the range in which the first pinion gear is operable as the result of the backlash in the rotation direction is displaced toward a torque-transmission-direction-surface side with respect to the second pinion gear.

8. The engine starter according to claim 1 , wherein the pinion unit has a configuration in which the first pinion gear and the second pinion gear are operable in the axial direction independently of each other.

9. The engine starter according to claim 8 , wherein the first pinion gear is axially movable by pushing the spring supporting the second pinion gear.

10. The engine starter according to claim 1 , a sum of a friction force in the axial direction of the first pinion gear and the second pinion gear and a load of compressing the spring to a maximum stroke does not exceed a load of pushing out the pinion.

11. The engine starter according to claim 1 , wherein the first pinion gear has a backlash in a radial direction with respect to a shaft of the pinion unit.

12. The engine starter according to claim 1 , wherein the second pinion gear has a chamfered shape on both sides of a tooth surface edge portion of the first pinion gear side.

13. The engine starter according to claim 12 , wherein the chamfered shape is different in shape between an edge on a side of a surface transmitting a rotation torque and an edge on a side of a surface not transmitting the rotation torque.

14. The engine starter according to claim 13 , wherein the chamfered shape causes a chamfered end portion to align with an end portion at a location where the end portion of the second pinion gear is exposed, by a backlash of the first pinion gear, to a surface without being hidden by the first pinion gear.

15. The engine starter according to claim 13 , wherein the chamfered shape has a chamfered shape along an involute of the tooth on any one of or both of the edge on the side of the surface transmitting the rotation torque and the edge on the side of the surface not transmitting the rotation torque.

16. The engine starter according to claim 1 , wherein the second pinion gear includes a protrusion, extending from the second pinion gear toward the first pinion gear in the axial direction, for meshing with the first pinion gear.

17. An engine starter comprising:
a starter motor;
a pinion unit coupled to an output-shaft side of the starter motor by means of a spline, for sliding in an axial direction;
a ring gear, which has a push-out mechanism for moving the pinion unit to an engaging position with the ring gear, meshes with a pinion of the pinion unit pushed out by the push-out mechanism, and receives a transmission of a rotation force of the starter motor to thereby start an engine,
wherein the pinion unit includes a pinion gear divided in the axial direction into two pinion gears, which are a first pinion gear having a protruded shape for synchronization, for first colliding with the ring gear upon start of meshing with the ring gear, and a second pinion gear for transmitting the rotation force after the meshing,
wherein the protruded shape for synchronization of the first pinion gear is constituted by the same number of protrusions as a number of teeth of the second pinion gear, and an area of a vertical cross section in the axial direction of the protrusion is configured to be smaller than a surface area of the second pinion gear, and
wherein the engine starter further comprises a second spring provided between the first pinion gear and the second pinion gear so that a friction force in a rotation direction of the first pinion gear and the second pinion gear is smaller than a friction force in the rotation direction of the first pinion gear and the ring gear.

Assignees

• Mizuno Daisuke
• Shimoji Haruhiko
• Kamei Koichiro
• Abe Masami
• Odahara Kazuhiro
• Kurishige Masahiko
• Kitano Hiroaki
• Tsukahara Yuhei
• Iezawa Masahiro
• Mitsubishi Electric Corp

Inventors

• Mizuno Daisuke
• Shimoji Haruhiko
• Kamei Koichiro
• Abe Masami
• Odahara Kazuhiro
• Kurishige Masahiko
• Kitano Hiroaki
• Tsukahara Yuhei
• Iezawa Masahiro

Classifications

• Y10T74/137

  Reduction gearing · CPC title

• F02N15/06 Primary

  the toothed gears being moved by axial displacement · CPC title

• F02N11/00 Primary

  Starting of engines by means of electric motors · CPC title

• F02N15/023

  of the overrunning type · CPC title

• F02N15/067

  the starter comprising an electro-magnetically actuated lever · CPC title