Apparatuses and methods for controlling a variable speed transmission

• US 20060021313A1
• Filed: 07/30/2004
• Published: 02/02/2006
• Est. Priority Date: 07/30/2004
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Keane, James C., Hojo, Hiroshi
• Granted Patent: US 7,850,555 B2
• Time in Patent Office: Days
• US Class Current: 56/11.800
• CPC Class Codes: A01D 69/08 Clutches

Abstract

Apparatuses and methods are disclosed for controlling a variable speed transmission including an actuator, a cam follower, and a speed adjustment cam. The actuator is rotatable through a first phase and a subsequent second phase, and includes an actuator cam surface and a variator. The cam follower is movable in response to contact with the actuator cam surface during rotation through the first phase, for actuating a coupler of the transmission between a disengaged position and an engaged position. The variator is movable along the speed adjustment cam during rotation through the second phase for enabling adjustment of a torque transfer mechanism associated with the transmission. By this configuration, control over the coupling of the transmission to a torque input such as a motor and control over the speed of the transmission are both enabled through rotation of a single actuator, and thus can be implemented in a self-propelled machine such as a lawnmower using a single operator-manipulated control.

Claims

1. An apparatus for controlling a variable-speed transmission, comprising:

(a) an actuator cam rotatable through a first phase and a subsequent second phase in response to operator control;

(b) a cam follower movable by the actuator cam during rotation through the first phase between a disengaged state at which the transmission is decoupled from a torque input and an engaged state at which the transmission is coupled to the torque input; and

(c) a speed adjustment device comprising a movable portion movable by the actuator cam during rotation through the second phase between a LOW speed state and a HIGH speed state.

2. The apparatus according to claim 1 wherein the movable portion of the speed adjustment device comprises a variator, the variator comprises a profiled variator surface, and the speed adjustment device comprises a speed adjustment cam surface substantially complementarily profiled relative to the variator surface.

3. The apparatus according to claim 1 wherein the variator movably contacts the actuator cam during rotation through the second phase.

4. The apparatus according to claim 3 wherein the actuator cam and the variator are rotatable about different axes.

5. The apparatus according to claim 3 wherein the actuator cam and the variator are rotatable about the same axis.

6. The apparatus according to claim 1 wherein the actuator cam and the movable portion rotate together as a unitary structure.

7. The apparatus according to claim 1 wherein the movable portion is rotatable about an axis, the speed adjustment device comprises an inclined speed adjustment cam surface, the movable portion comprises an inclined movable portion surface movable along the inclined speed adjustment cam surface during rotation of the actuator cam through the second phase, the inclined movable portion surface is angled relative to the axis, and the inclined speed adjustment cam surface is generally complementarily angled relative to the inclined movable portion surface.

8. The apparatus according to claim 7 wherein the speed adjustment device comprises a flat speed adjustment cam surface adjoining an end of the inclined speed adjustment cam surface and oriented generally normally to the axis, and the movable portion comprises a flat movable portion surface oriented generally parallel to the flat speed adjustment cam surface and movable along the flat speed adjustment cam surface during rotation of the actuator cam through the first phase.

9. An apparatus for controlling a variable-speed transmission, the transmission comprising a coupler for alternately engaging and disengaging power between the transmission and a motor, and an adjustable torque transfer mechanism interconnecting the transmission and the motor for varying a speed of the transmission, the apparatus comprising:

(a) an actuator rotatable through a first phase and a subsequent second phase, and comprising an actuator cam surface and a variator;

(b) a cam follower for actuating the coupler between a disengaged position and an engaged position, the cam follower movable in response to contact with the actuator cam surface during rotation through the first phase; and

(c) a speed adjustment cam, wherein the variator is movable along the speed adjustment cam during rotation through the second phase for enabling adjustment of the torque transfer mechanism.

10. The apparatus according to claim 9 wherein the actuator comprises an actuator cam rotatable through the first and second phases, the actuator cam includes the actuator cam surface, and the variator is movable along the speed adjustment cam in response to contact between the variator and the actuator cam surface.

11. The apparatus according to claim 10 wherein the variator comprises a variator surface and an arm, and the variator surface is movable along the speed adjustment cam by contact between the arm and the actuator cam surface in response to rotation of the actuator cam through the second phase.

12. The apparatus according to claim 11 wherein the actuator cam surface comprises a generally convex portion for contacting the arm.

13. The apparatus according to claim 11 wherein the actuator cam surface comprises a generally concave portion for contacting the arm.

14. The apparatus according to claim 9 wherein the actuator has a unitary structure comprising the actuator cam surface and the variator, and the actuator cam surface and the variator are rotatable together.

15. The apparatus according to claim 9 wherein the variator is rotatable about a variator axis, and the actuator cam is rotatable about an actuator cam axis oriented non-collinearly relative to the variator axis.

16. The apparatus according to claim 9 wherein the actuator cam and the variator are rotatable about the same axis.

17. The apparatus according to claim 9 wherein the variator is rotatable about an axis, the speed adjustment cam comprises an inclined speed adjustment cam surface, the variator comprises an inclined variator surface movable along the inclined speed adjustment cam surface during rotation of the actuator through the second phase, the inclined variator surface is angled relative to the axis, and the inclined speed adjustment cam surface is generally complementarily angled relative to the inclined variator surface.

18. The apparatus according to claim 17 wherein the speed adjustment cam comprises a flat speed adjustment cam surface adjoining an end of the inclined speed adjustment cam surface and oriented generally normally to the axis, and the variator comprises a flat variator surface oriented generally parallel to the flat speed adjustment cam surface and movable along the flat speed adjustment cam surface during rotation of the actuator through the first phase.

19. The apparatus according to claim 9 wherein the actuator cam surface comprises first and second actuator cam surface sections, and the cam follower is movable from contact with the first actuator cam surface section and into contact with the second actuator cam surface section in response to rotation of the actuator through the first phase.

20. The apparatus according to claim 19 wherein the actuator cam surface comprises a third actuator cam surface section, the variator comprises a variator surface and an arm, and the variator surface is movable along the speed adjustment cam in response to contact between the arm and the third actuator cam surface section.

21. The apparatus according to claim 19 wherein the variator comprises a variator surface and an arm, and the variator surface is movable along the speed adjustment cam in response to contact between the arm and the first actuator cam surface section.

22. The apparatus according to claim 9 wherein:

(a) the speed adjustment cam comprises a speed adjustment cam surface;

(b) the variator comprises a variator surface movable along the speed adjustment cam surface and rotatable about an axis;

(c) the variator surface comprises an inclined variator surface section angled relative to the axis, and a flat variator surface section generally normal to the axis;

(d) the speed adjustment cam surface comprises an inclined speed adjustment cam surface section generally complementarily angled relative to the inclined variator surface section, and a flat speed adjustment cam surface section generally parallel to the flat variator surface section;

(e) the flat variator surface section is movable along the flat speed adjustment cam surface section in response to rotation of the actuator through the first phase for rotating the variator without changing an axial position of the variator; and

(f) the inclined variator surface section is movable along the inclined speed adjustment cam surface section in response to rotation of the actuator through the second phase for rotating the variator while changing the axial position of the variator.

23. The apparatus according to claim 9 comprising a biasing member engaging the variator during rotation of the actuator through the second phase for biasing rotation of the variator generally in a direction from the second phase toward the first phase.

24. The apparatus according to claim 23 wherein the variator has an axis of rotation and the biasing member is generally oriented in an offset relation to the axis of rotation.

25. The apparatus according to claim 23 wherein the variator has an axis of rotation and the biasing member is generally oriented in coaxial relation to the axis of rotation.

26. The apparatus according to claim 9 wherein the variator and the speed adjustment cam are profiled for enabling axial displacement of the variator during movement of the variator along the speed adjustment cam, the torque transfer mechanism comprises a pulley for carrying an endless member drivable by the motor, the pulley comprises first and second pulley members rotatable about an input shaft of the transmission, and the first pulley member is axially translatable along the input shaft toward and away from the second pulley member in response to axial displacement of the variator for changing a radius of rotation of the endless member and a speed of the input shaft.

27. The apparatus according to claim 26 wherein the variator and the first and second pulley members are rotatable about the same axis.

28. An apparatus for controlling a variable-speed transmission, the transmission comprising a coupler for alternately engaging and disengaging power between the transmission and a motor, and an adjustable torque transfer mechanism interconnecting the transmission and the motor for varying a speed of the transmission, the apparatus comprising:

(a) an actuator cam rotatable through a first phase and a subsequent second phase and comprising first, second and third actuator cam surfaces;

(b) a cam follower for actuating the coupler between a disengaged position and an engaged position, the cam follower movable from contact with the first actuator cam surface at the disengaged position and into contact with the second actuator cam surface at the engaged position in response to rotation of the actuator cam through the first phase;

(c) a speed adjustment cam comprising a speed adjustment cam surface; and

(d) a variator comprising a variator surface, the variator rotatable through contact with the third actuator cam surface in response to rotation of the actuator cam through the second phase for enabling movement of the variator surface along the speed adjustment cam surface and adjustment of the torque transfer mechanism.

29. The apparatus according to claim 28 wherein the variator comprises an arm for contacting the third actuator cam surface during rotation through the second phase.

30. The apparatus according to claim 28 wherein the variator is rotatable about an axis, the variator surface comprises a variator inclined section angled relative to the axis, and the inclined section contacts the speed adjustment cam during rotation of the actuator cam through the second phase for axially displacing the variator.

31. The apparatus according to claim 30 wherein the speed adjustment cam comprises a stationary inclined section substantially complementarily angled relative to the variator inclined section for contacting the variator inclined section.

32. The apparatus according to claim 28 wherein the variator comprises a pulley variator for enabling axial adjustment of a variable-pitch pulley communicating with the transmission.

33. The apparatus according to claim 32 wherein the speed adjustment cam comprises a pulley cam on which the pulley variator travels.

34. An apparatus for controlling a variable-speed transmission, the transmission comprising a coupler for alternately engaging and disengaging power between the transmission and a motor, and an adjustable torque transfer mechanism interconnecting the transmission and the motor for varying a speed of the transmission, the apparatus comprising:

(a) an actuator cam rotatable through a first phase and a subsequent second phase and comprising first and second actuator cam surfaces;

(b) a cam follower for actuating the coupler between a disengaged position and an engaged position, the cam follower movable from contact with the first actuator cam surface at the disengaged position and into contact with the second actuator cam surface at the engaged position in response to rotation of the actuator cam through the first phase;

(c) a speed adjustment cam comprising a speed adjustment cam surface; and

(d) a variator comprising a variator surface, the variator rotatable through contact with the first actuator cam surface in response to rotation of the actuator cam through the second phase for enabling movement of the variator surface along the speed adjustment cam surface and adjustment of the torque transfer mechanism.

35. The apparatus according to claim 34 wherein the variator comprises an arm for contacting the first actuator cam surface during rotation through the second phase.

36. The apparatus according to claim 34 wherein the variator is rotatable about an axis, the variator surface comprises a variator inclined section angled relative to the axis, and the inclined section contacts the speed adjustment cam during rotation of the actuator cam through the second phase for axially displacing the variator.

37. The apparatus according to claim 36 wherein the speed adjustment cam comprises a stationary inclined section substantially complementarily angled relative to the variator inclined section for contacting the variator inclined section.

38. The apparatus according to claim 34 wherein the variator comprises a pulley variator for enabling axial adjustment of a variable-pitch pulley communicating with the transmission.

39. The apparatus according to claim 38 wherein the speed adjustment cam comprises a pulley cam on which the pulley variator travels.

40. An apparatus for controlling a variable-speed transmission, the transmission comprising a coupler for alternately engaging and disengaging power between the transmission and a motor, and an adjustable torque transfer mechanism interconnecting the transmission and the motor for varying a speed of the transmission, the apparatus comprising:

(a) an actuator cam rotatable through a first phase and a subsequent second phase and comprising a variator surface rotatable therewith;

(b) a cam follower for actuating the coupler between a disengaged position and an engaged position through contact with the actuator cam in response to rotation of the actuator cam through the first phase; and

(c) a speed adjustment cam comprising a speed adjustment cam surface, the speed adjustment cam surface comprising a flat and an incline, wherein the variator surface is movable along the flat response to rotation of the actuator cam through the first phase, and the variator surface is movable along the incline in response to rotation of the actuator cam through the second phase for enabling adjustment of the torque transfer mechanism.

41. The apparatus according to claim 40 wherein the actuator cam comprises first and second actuator cam surfaces, and the cam follower is movable from contact with the first actuator cam surface at the disengaged position and into contact with the second actuator cam surface at the engaged position in response to rotation of the actuator cam through the first phase.

42. The apparatus according to claim 40 wherein the actuator cam is rotatable about an axis and the speed adjustment cam is coaxially disposed about the axis.

43. The apparatus according to claim 42 wherein the speed adjustment cam is stationary.

44. The apparatus according to claim 40 wherein the variator surface is substantially complementarily profiled relative to the speed adjustment cam surface.

45. The apparatus according to claim 40 wherein the variator surface is profiled for enabling axial adjustment of a variable-pitch pulley communicating with the transmission in response to movement of the variator surface along the incline of the speed adjustment cam surface.

46. The apparatus according to claim 45 wherein the speed adjustment cam comprises a pulley cam on which the pulley variator surface travels.

47. A method for controlling a variable-speed transmission, comprising:

(a) rotating an actuator cam through a first arc to actuate a cam follower, whereby the actuator cam causes the transmission to be coupled with a torque input; and

(b) rotating the actuator cam through a second arc following the first arc to actuate a speed-varying device of the transmission, whereby the actuator cam causes a speed of the transmission to be adjusted.

48. The method according to claim 47 wherein rotating the actuator cam comprises operating a linking member communicating with the actuator cam.

49. The method according to claim 47 wherein rotating the actuator cam comprises operating a control component mounted to a self-propelled machine.

50. The method according to claim 47 wherein the speed-varying device comprises a variable-pitch pulley rotating with a shaft communicating with the transmission.

51. The method according to claim 47 wherein the cam follower is initially actuated without actuating the speed-varying device, and the speed-varying device is initially actuated without changing a position of the cam follower.

52. The apparatus according to claim 47 wherein rotating the actuator cam through the first arc actuates the cam follower between a disengaged position at which the cam follower contacts a first surface of the actuator cam and an engaged position at which the cam follower contacts a second surface of the actuator cam, and rotating the actuator cam through the second arc actuates the speed-varying device through moving contact of the speed-varying device with a third surface of the actuator cam.

53. The apparatus according to claim 47 wherein rotating the actuator cam through the first arc actuates the cam follower between a disengaged position at which the cam follower contacts a first surface of the actuator cam and an engaged position at which the cam follower contacts a second surface of the actuator cam, and rotating the actuator cam through the second arc actuates the speed-varying device through moving contact of the speed-varying device with the first surface of the actuator cam.

54. The apparatus according to claim 47 wherein rotating the actuator cam through the first arc causes the speed-varying device to move along a flat surface, and rotating the actuator cam through the second arc causes the speed-varying device to move along an inclined surface.