JPH05296306A - Continuously variable transmission - Google Patents

Abstract

PURPOSE:To simplify the structure of a variable-diameter wheel made variable in a diameter of a transmission surface over which a rotation transmission member is wound, and an adjusting mechanism for the transmission surface diameter. CONSTITUTION:In an output pulley 4 which is a variable-diameter wheel, a pair of movable blocks 8 are disposed in a manner that conical surfaces 8a each formed with a plurality of radial guide grooves 12 are opposed to each other and so that these conical surfaces 8a may be moved toward or away from each other. A plurality of movable pulley members 9 are provided in a manner to be bridged between corresponding ones of the guide grooves 12 of the paired movable blocks 8 and they are radially movable along the guide grooves 12. Further, the output pulley further comprises a plurality of coil springs 10 for making mutual connection of adjoining ones of the movable pulley members 9 and for energizing them in the direction to cause them to approach each other, and a pair of pressing members 11 for pressing the paired movable blocks 8 from both sides thereof in the directions to cause them to be moved toward or away from each other. A V-belt 7 is stretched over a V-groove 13 formed in an outer periphery of the movable pulley member 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuously variable transmission.

[0002]

2. Description of the Related Art Conventionally, gears and step wheels have been used as transmissions for power transmission, but these have a problem that they can only perform stepwise speed adjustment.

Therefore, for example, Japanese Patent Laid-Open No. 60-23416
As disclosed in Japanese Patent Laid-Open No. 2-299355 and Japanese Unexamined Patent Publication No. 1-299355, an input shaft having an input wheel and an output shaft having an output wheel are arranged in parallel, and rotation transmission of a belt or the like is performed between the input wheel and the output wheel. There has been proposed a continuously variable transmission in which a member is hung and at least one of an input wheel and an output wheel is a variable diameter wheel in which a diameter of a transmission surface on which a transmission member is hung is variable.

[0004]

However, the conventional continuously variable transmission as described above has a problem that the structure of the variable diameter wheel and the mechanism for adjusting the diameter of the transmission surface thereof are complicated.

The object of the present invention is to solve the above problems,
An object of the present invention is to provide a continuously variable transmission having a simple structure of a variable diameter wheel and a mechanism for adjusting the diameter of its transmission surface.

[0006]

In a continuously variable transmission according to the present invention, an input shaft having an input wheel and an output shaft having an output wheel are arranged in parallel, and a rotation transmission member is hung on the input wheel and the output wheel. In a continuously variable transmission in which at least one of the input wheel and the output wheel is a variable diameter wheel in which a diameter of a transmission surface on which a transmission member is hung is variable, the variable diameter wheel includes a plurality of radial guide portions. A pair of movable blocks arranged so that the conical surfaces formed with the conical surfaces are opposed to each other and are movable in a direction toward and away from each other, and are bridged between corresponding guide portions of the pair of movable blocks. A plurality of movable pulley pieces that can move in a radial direction along the guide portion, a plurality of elastic members that connect adjacent movable pulley pieces and urge them toward each other, and a pair of movable blocks on both sides. From each other And it is characterized in that it comprises a pressing member of a pair of pressing in a direction approaching.

[0007]

Since the adjacent movable pulley pieces of the variable-diameter wheels are urged in the direction toward each other by the expansion / contraction member, the movable pulley pieces are spaced along the guide portions formed on the conical surfaces of the pair of movable blocks. Tends to move inward, that is, in the radial direction. When the movable pulley pieces try to move inward in the radial direction, the pair of movable blocks are pushed by the wedge-shaped movable pulley pieces and try to move in the directions away from each other, so that they are pressed against the pressing members on both sides. Then, the movable block and the movable pulley piece are stopped at such a position.

When the distance between the pair of pressing members of the variable-diameter wheel is reduced, the distance between the pair of movable blocks is also reduced, and the distance between these conical surfaces is also reduced, so that the wedge-shaped movable pulley piece is pushed onto the conical surface. It is moved to the outer side in the radial direction. When the movable pulley piece moves outward in the radial direction, the distance between them increases and the elastic member expands. The movable pulley piece moves radially outward due to the urging force of the elastic member, and in the state of the guide portion of the conical surface. It is pressed against the part and stopped at that position. By moving the movable pulley piece outward in the radial direction in this manner, the diameter of the transmission surface on the outer periphery of the movable pulley piece increases.

When the distance between the pair of pressing members is increased, the wedge-shaped movable pulley piece is moved inward in the radial direction by the urging force of the expansion / contraction member. The member shrinks. When the movable pulley piece moves inward in the radial direction, the pair of movable blocks are pushed in a direction away from each other, and are pressed against the pressing members on both sides, and the movable block and the movable pulley piece are stopped at this position. As the movable pulley piece thus moves inward in the radial direction, the diameter of the transmission surface on the outer circumference of the movable pulley piece becomes smaller.

By changing the diameter of the transmission surface of the variable diameter wheel as described above, the gear ratio can be changed. Further, by continuously changing the distance between the pair of pressing members, the diameter of the transmission surface can be continuously changed, and continuously variable speed can be achieved.

The variable diameter wheel is composed of only a pair of movable blocks, a plurality of movable pulley pieces, a plurality of elastic members and a pair of pressing members, and the diameter of the transmission surface is changed by changing the distance between the pair of pressing members. , The structure of the variable diameter wheel and the mechanism for adjusting the diameter of the transmission surface thereof are simple.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 3 show the entire structure of a continuously variable transmission, which comprises an input pulley (input wheel) (2) provided on an input shaft (motor shaft) (1) and an output shaft. Output pulley (4) provided on (3), movable shaft (5), tension pulley (6) provided on movable shaft (5), input pulley (2), output pulley (4) And tension pulley
It is composed of a V belt (rotation transmitting member) (7) hung on (6). The input shaft (1) and the output shaft (3) are fixedly arranged so as to be parallel to each other. The movable shaft (5) is parallel to the input shaft (1) and the output shaft (3) and is arranged so as to be movable in a direction perpendicular to the axis. Input pulley
The (2) and tension pulleys (6) are ordinary V-belt pulleys and are fixed to the input shaft (1) and the movable shaft (5), respectively.

The output pulley (4) is a variable diameter wheel whose transmission surface diameter can be continuously changed, and includes a pair of movable blocks.
(8) A plurality of movable pulley pieces (9), a plurality of coil springs (expandable members) (10), and a pair of pressing members (11). The movable block (8) has a substantially disc shape, and is attached to the output shaft (3) at its center so that it can move in the axial direction but does not rotate, for example, through splines, serrations, etc. not shown. .. block
Conical surfaces (8a) that are higher on the center side are formed on the opposing surfaces of (8), and radial guide grooves (guide portions) (12) of rectangular cross section are formed on these conical surfaces (8a) at equal angles in the circumferential direction. It is formed with. The movable pulley piece (9) has a trapezoidal wedge shape and is bridged between the corresponding grooves (12) of the pair of blocks (8). The sloped parts on both sides of each pulley piece (9) are fitted in the groove so that the side end faces come in contact with the bottom of the groove (12), and each pulley piece (9) fits in the groove (12). It is movable along the radial direction. The V-belt (7) fits in the central portion of the outer peripheral side of each pulley piece (9) in the axial direction.
3) is formed, and this part is the transmission surface of the output pulley (4). For example, two coil springs (10) are arranged between adjacent pulley pieces (9) to connect the pulley pieces (9) to each other so as to urge the adjacent pulley pieces (9) toward each other in the circumferential direction. ing. The pressing member (11) has a ring shape,
A pair of blocks (8) are mounted on both sides of the output shaft (3) for axial movement. Then, the pressing member (11), by an appropriate means such as a screw,
It is designed to be fixed at any position on the output shaft (3).

Since the adjacent pulley pieces (9) of the output pulley (4) are urged by the springs (10) in a direction of approaching each other in the circumferential direction, the pulley pieces (9) are conical surfaces of the block (8). (8
Along the groove (12) formed in a), it tries to move inward in the direction in which the circumferential interval becomes smaller, that is, in the radial direction. When the pulley pieces (9) try to move inward in the radial direction, the pair of blocks (8) are pushed by the wedge-shaped pulley pieces (9) and try to move away from each other, so that the pressing members (11) on both sides are pushed. Press against. Then, the block (8) and the pulley piece (9) are stopped at such a position.

As shown in FIGS. 1 and 2, the output pulley
When the distance between the pair of pressing members (11) in (4) is reduced, the distance between the pair of blocks (8) is also reduced, and these conical surfaces (8
Since the interval of a) is also small, the wedge-shaped pulley piece (9) is pushed by the conical surface and moves outward in the radial direction. As the pulley pieces (9) move radially outward, the circumferential spacing between them increases and the spring (10) extends, and the pulley pieces (9) move toward the spring (1
Due to the urging force of (0), it moves outward in the radial direction and is pressed against the bottom portion of the groove (12) of the conical surface (8a) and stopped at that position. And thus the pulley piece (9)
Is moved radially outward, the diameter of the transmission surface on the outer periphery of the pulley piece (9) increases.

As shown in FIGS. 3 and 4, if the distance between the pair of pressing members (11) is increased, a wedge-shaped pulley piece (9) is formed.
Is moved radially inward by the urging force of the spring (10),
As a result, the gap between the adjacent pulley pieces (9) in the circumferential direction becomes small, and the spring (10) contracts. When the pulley pieces (9) move inward in the radial direction, the pair of blocks (8) are pushed in the directions away from each other, and are pressed against the pressing members (11) on both sides,
The block (8) and pulley piece (9) are stopped in this position. As the pulley piece (9) moves inward in the radial direction, the diameter of the transmission surface on the outer circumference of the pulley piece (9) becomes smaller.

When the diameter of the transmission surface of the input pulley (2) changes in this way, the length of the V belt (7) hung on it changes, so that the movable shaft (5) is moved appropriately, The tension pulley (6) ensures that proper tension is always generated on the V-belt (7).

In the continuously variable transmission described above, the rotation of the input shaft (1) by a motor (not shown) is transmitted to the output pulley (4) via the input pulley (2) and the V belt (7), and thereby the output shaft (4). (3) is rotated. The gear ratio can be changed by changing the diameter of the transmission surface of the output pulley (4) as described above. Further, the diameter of the transmission surface can be continuously changed by continuously changing the distance between the pair of pressing members (11), and thus the gear ratio can be continuously changed and continuously variable speed can be achieved. ..

In the above embodiment, the output pulley (4) is a variable radial wheel, but the input pulley may be a variable radial wheel. Further, both the input pulley and the output pulley may have variable diameters.

[0021]

As described above, according to the continuously variable transmission of the present invention, the structure of the variable diameter wheel and the mechanism for adjusting the diameter of the transmission surface thereof can be simplified. The whole structure can be simple and inexpensive.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view of a continuously variable transmission showing an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of a portion of the output pulley shown in FIG.

FIG. 3 is a partially cutaway side view of the continuously variable transmission showing a state in which the diameter of the transmission surface of the output pulley is smaller than that in the state of FIG.

4 is a vertical cross-sectional view of a portion of the output pulley of FIG.

FIG. 5 is an exploded perspective view of an output pulley.

[Explanation of symbols]

 (1) Input shaft (motor shaft) (2) Input pulley (input wheel) (3) Output shaft (4) Output pulley (output wheel) (7) V-belt (rotation transmitting member) (8) Movable block (8a) Conical surface (9) Movable pulley piece (10) Coil spring (expandable member) (11) Pressing member (12) Guide groove (guide portion) (13) V groove

Claims (1)

[Claims] 1. An input shaft having an input wheel and an output shaft having an output wheel are arranged in parallel, a rotation transmission member is hung on the input wheel and the output wheel, and at least one of the input wheel and the output wheel is
In a continuously variable transmission which is a variable diameter wheel in which a diameter of a transmission surface on which a transmission member is hung is variable, the variable diameter wheel has conical surfaces formed with a plurality of radial guide portions facing each other, and A pair of movable blocks arranged so that the conical surfaces can move in directions away from each other, and a plurality of movable blocks that extend over the corresponding guide portions of the pair of movable blocks and can move in a radial direction along the guide portions. Movable pulley pieces, a plurality of elastic members for connecting adjacent movable pulley pieces to urge them toward each other, and a pair of pressing members for pressing a pair of movable blocks from both sides toward each other. A continuously variable transmission, comprising: