Infinite speed ratio transmission device and assembly method thereof

• US 6,258,003 B1
• Filed: 02/11/2000
• Issued: 07/10/2001
• Est. Priority Date: 02/15/1999
• Status: Expired due to Fees

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Hirano, Hiroyuki, Nakano, Masaki
• Primary Examiner(s): Wright, Dirk
• Application Number:
  US09/502,017
• Time in Patent Office: 515 Days
• Field of Search: 475/216, 746/06.R
• US Class Current: 475/216
• CPC Class Codes: F16H 15/38 with two members B having hollow toroid surfaces opposite to each other, the member or members A being adjustably mounted between the surfaces
• CPC Class Codes: F16H 2037/088 Power split variators with summing differentials, with the input of the CVT connected or connectable to the input shaft
• CPC Class Codes: F16H 2037/0886 with switching means, e.g. to change ranges
• CPC Class Codes: F16H 37/086 CVT using two coaxial friction members cooperating with at least one intermediate friction member

Abstract

An upper link (100) connecting four trunnions (30) of a first toroidal unit (2A) and second toroidal unit (2B) is formed of a first part (102) corresponding to the first toroidal unit (2A) and a second part (101) corresponding to the second toroidal unit (2B). The first part (102) is supported in a casing (14) via a first upper link supporting member (27X), while the second part (101) is fixed to the casing (14) via a second upper link supporting member (27Y). The first part (102) is also fixed to the second part (101) by bolts 105). The rotation outputs of the first toroidal unit (2A) and second toroidal unit (2B) are transmitted to a planetary gear unit (5) via a chain (40) from an output sprocket (24) provided between the two toroidal units (2A, 2B).

Claims

1. An infinite speed ratio transmission device for a vehicle, comprising:

an input shaft;

a first toroidal unit comprising a first input disk which rotates together with the input shaft, a first output disk, and two power rollers gripped between the first input disk and the first output disk;

a second toroidal unit comprising a second input disk which rotates together with the input shaft, a second output disk, and two power rollers gripped between the second input disk and the second output disk, the first output disk and the second output disk being disposed coaxially and adjacent to each other;

an output sprocket which is disposed between and rotates together with the first output disk and the second output disk;

four trunnions which support the four power rollers of the first toroidal unit and the second toroidal unit;

an upper link holding the upper end of the four trunnions, the upper link comprising a first part holding the two trunnions of the first toroidal unit, and a second part holding the two trunnions of the second toroidal unit, the first part and the second part being formed separately and fixed to each other;

a fixed speed ratio transmission which transmits a rotation of the input shaft at a fixed speed ratio to an output gear;

a planetary gear set comprising a sun gear joined to a sprocket, a planet carrier which rotates together with the output gear, and a ring gear which rotates according to a relative rotation of the sun gear and the planet carrier;

a chain connecting the output sprocket and the sprocket;

a casing housing the first toroidal unit, the second toroidal unit and the planetary gear set;

a first upper link supporting member fixed to the casing which supports the first part in the casing;

a second upper link supporting member fixed to the casing which supports the second part in the casing; and

an intermediate wall fixed to the casing which supports the output sprocket free to rotate.

2. An infinite speed ratio transmission device as defined in claim 1, wherein the casing has an opening formed in a position facing the upper link.

3. An infinite speed ratio transmission device as defined in claim 2, wherein the casing has other openings which form approximate right angles with the input shaft.

4. An infinite speed ratio transmission device as defined in claim 1, wherein the second part comprises a pair of arm-shaped connecting parts fixed to the first part.

5. An infinite speed ratio transmission device as defined in claim 4, wherein the casing has an opening formed in a position facing the upper link, and the connecting part is disposed on the outside of the first upper link supporting member viewed from the opening so that the first upper link supporting member can be fixed to the casing without interfering with the connecting part in a state where the second part has been supported in the casing by the second upper link supporting member.

6. An infinite speed ratio transmission device as defined in claim 4, wherein a bent part is formed midway in each of the connecting parts so that the first part and the second part have an identical height with respect to the input shaft.

7. An infinite speed ratio transmission device as defined in claim 1, wherein the intermediate wall comprises a front partition interposed between the output disk of the first toroidal unit and the output sprocket, a rear partition interposed between the output disk of the second toroidal unit and the output sprocket, and a member for fixing the front partition to the rear partition.

8. A method of assembling an infinite speed ratio transmission device for a vehicle, the transmission device comprising an input shaft, a first toroidal unit comprising a first input disk which rotates together with the input shaft, a first output disk, and two power rollers gripped between the first input disk and the first output disk, a second toroidal unit comprising a second input disk which rotates together with the input shaft, a second output disk, and two power rollers gripped between the second input disk and the second output disk, the first output disk and the second output disk being disposed coaxially and adjacent to each other, an output sprocket which is disposed between and rotates together with the first output disk and the second output disk, four trunnions which support the four power rollers of the first toroidal unit and the second toroidal unit, an upper link holding the upper end of the four trunnions, the upper link comprising a first part holding the two trunnions of the first toroidal unit, and a second part holding the two trunnions of the second toroidal unit, the first part and the second part being formed separately and fixed to each other, a fixed speed ratio transmission which transmits a rotation of the input shaft at a fixed speed ratio to an output gear, a planetary gear set comprising a sun gear joined to a sprocket, a planet carrier which rotates together with the output gear, and a ring gear which rotates according to a relative rotation of the sun gear and the planet carrier, a chain connecting the output sprocket and the sprocket, a casing housing the first toroidal unit, the second toroidal unit and the planetary gear set, a first upper link supporting member fixed to the casing which supports the first part in the casing, a second upper link supporting member fixed to the casing which supports the second part in the casing, and an intermediate wall fixed to the casing which supports the output sprocket free to rotate, the assembly method comprising:

fixing the second upper link supporting member to the casing;

fitting the second part to the second upper link supporting member;

setting the output sprocket at a predetermined position in the casing;

inserting the sprocket around which the chain has been looped and the planetary gear unit in the casing;

looping the chain around the output sprocket;

setting the sprocket and the planetary gear unit at a predetermined position in the casing;

fixing the first upper link supporting member to the casing;

fitting the first part to the first upper link supporting member; and

joining the first part to the second part.

9. A method of assembling an infinite speed ratio transmission device for a vehicle, the transmission device comprising an input shaft, a first toroidal unit comprising a first input disk which rotates together with the input shaft, a first output disk, and two power rollers gripped between the first input disk and the first output disk, a second toroidal unit comprising a second input disk which rotates together with the input shaft, a second output disk, and two power rollers gripped between the second input disk and the second output disk, the first output disk and the second output disk being disposed coaxially and adjacent to each other, an output sprocket which is disposed between and rotates together with the first output disk and the second output disk, four trunnions which support the four power rollers of the first toroidal unit and the second toroidal unit, an upper link holding the upper end of the four trunnions, the upper link comprising a first part holding the two trunnions of the first toroidal unit, and a second part holding the two trunnions of the second toroidal unit, the first part and the second part being formed separately and fixed to each other, a fixed speed ratio transmission which transmits a rotation of the input shaft at a fixed speed ratio to an output gear, a planetary gear set comprising a sun gear joined to a sprocket, a planet carrier which rotates together with the output gear, and a ring gear which rotates according to a relative rotation of the sun gear and the planet carrier, a chain connecting the output sprocket and the sprocket, a casing housing the first toroidal unit, the second toroidal unit and the planetary gear set, a first upper link supporting member fixed to the casing which supports the first part in the casing, a second upper link supporting member fixed to the casing which supports the second part in the casing, and an intermediate wall fixed to the casing which supports the output sprocket free to rotate, the intermediate wall comprising a front partition disposed between the first output disk and the output sprocket, a rear partition disposed between the second output disk and the output sprocket, and a fixing member which fixes the front partition to the rear partition, the assembly method comprising:

fixing the second upper link supporting member to the casing;

fitting the second part to the second upper link supporting member;

setting the output sprocket at a predetermined position in the casing together with the rear partition;

inserting the sprocket around which the chain has been looped and the planetary gear unit in the casing;

looping the chain around the output sprocket;

setting the sprocket and the planetary gear unit at a predetermined position in the casing;

fixing the front partition to the rear partition by the fixing member;

fixing the first upper link supporting member to the casing;

fitting the first part to the first upper link supporting member; and

joining the first part to the second part.

10. A method of assembling an infinite speed ratio transmission for a vehicle, the transmission device comprising an input shaft, a first toroidal unit comprising a first input disk which rotates together with the input shaft, a first output disk, and two power rollers gripped between the first input disk and the first output disk, a second toroidal unit comprising a second input disk which rotates together with the input shaft, a second output disk, and two power rollers gripped between the second input disk and the second output disk, the first output disk and the second output disk being disposed coaxially and adjacent to each other, an output sprocket which is disposed between and rotates together with the first output disk and the second output disk, four trunnions which support the four power rollers of the first toroidal unit and the second toroidal unit, an upper link holding the upper end of the four trunnions, the upper link comprising a first part holding the two trunnions of the first toroidal unit, and a second part holding the two trunnions of the second toroidal unit, the first part and the second part being formed separately and fixed to each other, a fixed speed ratio transmission which transmits a rotation of the input shaft at a fixed speed ratio to an output gear, a planetary gear set comprising a sun gear joined to a sprocket, a planet carrier which rotates together with the output gear, and a ring gear which rotates according to a relative rotation of the sun gear and the planet carrier, a chain connecting the output sprocket and the sprocket, a casing housing the first toroidal unit, the second toroidal unit and the planetary gear set, a first upper link supporting member fixed to the casing which supports the first part in the casing, a second upper link supporting member fixed to the casing which supports the second part in the casing, and an intermediate wall fixed to the casing which supports the output sprocket free to rotate, the assembly method comprising:

fixing the second upper link supporting member to the casing;

fitting the second part to the second upper link supporting member;

looping the chain around the output sprocket and the sprocket;

fitting the intermediate wall on the output sprocket;

setting the output sprocket on which the intermediate wall is fitted and the planetary gear set in which the sprocket is combined with the output sprocket via the chain, at a predetermined position in the casing;

fixing the first upper link supporting member to the casing fitting the first part to the first upper link supporting member; and

joining the first part to the second part.