CONTINUOUSLY VARIABLE TRANSMISSION MECHANISM AND TRANSMISSION USING THE SAME

• US 20110319222A1
• Filed: 02/10/2009
• Published: 12/29/2011
• Est. Priority Date: 02/10/2009
• Status: Abandoned Application

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Ogawa, Hiroyuki, Murakami, Akira, Tomomatsu, Daisuke
• Application Number:
  US13/001,453
• Publication Number:
  US 20110319222A1
• Time in Patent Office: Days
• US Class Current: 476/55
• CPC Class Codes: F16H 15/28 with external friction surface
• CPC Class Codes: F16H 37/021 toothed gearing combined with continuous variable friction gearing

Abstract

A continuously variable transmission adapted to set a speed change ratio in accordance with a tilt angle of a rolling member mediating a torque being transmitted, and to transmit a torque among three elements. The transmission mechanism is provided with a rolling member having a smooth outer face and capable of tilting a rotational center axis thereof, and a rotary member arranged to be contacted with a predetermined portion of the outer face of the rolling member in a torque transmittable manner. Specifically, the continuously variable transmission mechanism is configured to vary a rotational speed of the rotary member by changing a rotation radius of a contact point between the rolling member and the rotary member by tilting the rotational center axis of the rolling member.

Claims

1. A continuously variable transmission mechanism, which has a rolling member having a smooth outer face and capable of tilting a rotational center axis thereof, and a rotary member arranged to be contacted with a predetermined portion of the outer face of the rolling member in a torque transmittable manner, and which is configured to vary a rotational speed of the rotary member by tilting the rotational center axis of the rolling member to change a rotation radius of a contact point at which the rotary member is contacted with the rolling member in a torque transmittable manner, comprising:

a first rotary member whose outer circumferential face is contacted with the rolling member; and

a second rotary member and a third rotary member, which are contacted with the outer face of the rolling member in a torque transmittable manner at a side opposite to a side to which the first rotary member is contacted across the rotational center axis, and which are adapted to rotate relatively with the first rotary member.

2. The continuously variable transmission mechanism as claimed in claim 1, further comprising:

a tilt angle adjusting mechanism, which is adapted to incline the rolling member thereby changing an angle between the rotational center axis of the rolling member and the rotational center axis of the first rotary member in a plane including the rotational center axis of the first rotary member.

3. The continuously variable transmission mechanism as claimed in claim 1, wherein:

the second rotary member and the third rotary member are contacted with the outer face of the rolling member in a torque transmittable manner on both sides of a line passing through a center of the rolling member and a contact point at which the rolling member is contacted with the first rotary member; and

a rotational speed of one of the second and the third rotary members is lowered by inclining the rotational center axis of the rolling member in a manner to increase a rotational speed of the other rotary member.

4. A transmission using the continuously variable transmission as claimed in claim 1, comprising:

an input member, which is connected with the first rotary member;

a first intermediate shaft, which is connected with the second rotary member;

a second intermediate shaft, which is connected with the third rotary member;

an output member, which is connected selectively with the first intermediate shaft and the second intermediate shaft in a torque transmittable manner;

a first transmission mechanism, which is arranged between the first intermediate shaft and the output member, and which is adapted to set a ratio between rotational speeds of the first intermediate shaft and the output member to a predetermined ratio;

a first switching mechanism, which is adapted to allow and to disable the first transmission mechanism to transmit the torque selectively;

a second transmission mechanism, which is arranged between the second intermediate shaft and the output member, and which is adapted to set a ratio between rotational speeds of the second intermediate shaft and the output member to a ratio different from the ratio set by the first transmission mechanism; and

a second switching mechanism, which is adapted to allow and to disable the second transmission mechanism to transmit the torque selectively.

5. The transmission as claimed in claim 4, wherein:

the first switching mechanism includes an engagement member adapted to connect the first transmission mechanism selectively with the first intermediate shaft and the output member; and

the second switching mechanism includes another engagement member adapted to connect the second transmission mechanism selectively with the second intermediate shaft and the output member; and

the transmission further comprises

a control means, which is adapted to connect the engagement member of one of the first and the second switching mechanisms with the intermediate shafts or the output member to be connected therewith, while disconnecting the engagement member of the other switching mechanism from the intermediate shaft or the output member being connected therewith, when the rotational speed of said one of the first and the second switching mechanisms is synchronized with the rotational speed of the intermediate shaft or the output shaft to be connected therewith, under the situation where the torque is being transmitted by the other switching mechanism.

6. The transmission as claimed in claim 4, wherein:

the first transmission mechanism and the second transmission mechanism include a pair of gears meshing with each other.

7. The transmission as claimed in claim 4, wherein:

the first switching mechanism and the second switching mechanism include a dog clutch.

8. The continuously variable transmission mechanism as claimed in claim 2, wherein:

the second rotary member and the third rotary member are contacted with the outer face of the rolling member in a torque transmittable manner on both sides of a line passing through a center of the rolling member and a contact point at which the rolling member is contacted with the first rotary member; and

a rotational speed of one of the second and the third rotary members is lowered by inclining the rotational center axis of the rolling member in a manner to increase a rotational speed of the other rotary member.

9. A transmission using the continuously variable transmission as claimed in claim 2, comprising:

an input member, which is connected with the first rotary member;

a first intermediate shaft, which is connected with the second rotary member;

a second intermediate shaft, which is connected with the third rotary member;

an output member, which is connected selectively with the first intermediate shaft and the second intermediate shaft in a torque transmittable manner;

a first transmission mechanism, which is arranged between the first intermediate shaft and the output member, and which is adapted to set a ratio between rotational speeds of the first intermediate shaft and the output member to a predetermined ratio;

a first switching mechanism, which is adapted to allow and to disable the first transmission mechanism to transmit the torque selectively;

a second transmission mechanism, which is arranged between the second intermediate shaft and the output member, and which is adapted to set a ratio between rotational speeds of the second intermediate shaft and the output member to a ratio different from the ratio set by the first transmission mechanism; and

a second switching mechanism, which is adapted to allow and to disable the second transmission mechanism to transmit the torque selectively.

10. A transmission using the continuously variable transmission as claimed in claim 3, comprising:

an input member, which is connected with the first rotary member;

a first intermediate shaft, which is connected with the second rotary member;

a second intermediate shaft, which is connected with the third rotary member;

an output member, which is connected selectively with the first intermediate shaft and the second intermediate shaft in a torque transmittable manner;

a first transmission mechanism, which is arranged between the first intermediate shaft and the output member, and which is adapted to set a ratio between rotational speeds of the first intermediate shaft and the output member to a predetermined ratio;

a first switching mechanism, which is adapted to allow and to disable the first transmission mechanism to transmit the torque selectively;

a second transmission mechanism, which is arranged between the second intermediate shaft and the output member, and which is adapted to set a ratio between rotational speeds of the second intermediate shaft and the output member to a ratio different from the ratio set by the first transmission mechanism; and

a second switching mechanism, which is adapted to allow and to disable the second transmission mechanism to transmit the torque selectively.

11. The transmission as claimed in claim 9, wherein:

the first switching mechanism includes an engagement member adapted to connect the first transmission mechanism selectively with the first intermediate shaft and the output member; and

the second switching mechanism includes another engagement member adapted to connect the second transmission mechanism selectively with the second intermediate shaft and the output member; and

the transmission further comprises

a control means, which is adapted to connect the engagement member of one of the first and the second switching mechanisms with the intermediate shafts or the output member to be connected therewith, while disconnecting the engagement member of the other switching mechanism from the intermediate shaft or the output member being connected therewith, when the rotational speed of said one of the first and the second switching mechanisms is synchronized with the rotational speed of the intermediate shaft or the output shaft to be connected therewith, under the situation where the torque is being transmitted by the other switching mechanism.

12. The transmission as claimed in claim 10, wherein:

the first switching mechanism includes an engagement member adapted to connect the first transmission mechanism selectively with the first intermediate shaft and the output member; and

the second switching mechanism includes another engagement member adapted to connect the second transmission mechanism selectively with the second intermediate shaft and the output member; and

the transmission further comprises

a control means, which is adapted to connect the engagement member of one of the first and the second switching mechanisms with the intermediate shafts or the output member to be connected therewith, while disconnecting the engagement member of the other switching mechanism from the intermediate shaft or the output member being connected therewith, when the rotational speed of said one of the first and the second switching mechanisms is synchronized with the rotational speed of the intermediate shaft or the output shaft to be connected therewith, under the situation where the torque is being transmitted by the other switching mechanism.

13. The transmission as claimed in claim 5, wherein:

the first transmission mechanism and the second transmission mechanism include a pair of gears meshing with each other.

14. The transmission as claimed in claim 9, wherein:

the first transmission mechanism and the second transmission mechanism include a pair of gears meshing with each other.

15. The transmission as claimed in claim 10, wherein:

the first transmission mechanism and the second transmission mechanism include a pair of gears meshing with each other.

16. The transmission as claimed in claim 5, wherein:

the first switching mechanism and the second switching mechanism include a dog clutch.

17. The transmission as claimed in claim 6, wherein:

the first switching mechanism and the second switching mechanism include a dog clutch.

18. The transmission as claimed in claim 9, wherein:

the first switching mechanism and the second switching mechanism include a dog clutch.

19. The transmission as claimed in claim 10, wherein:

the first switching mechanism and the second switching mechanism include a dog clutch.