JP3343706B2 - Torque cam mechanism for continuously variable transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Conventionally, a continuously variable transmission includes a pair of detachable input side pulleys attached to an input shaft,
With a belt mounted between a pair of detachable output side pulleys attached to the output shaft, the rotation of the input shaft can be steplessly changed and transmitted to the output shaft, A torque cam mechanism is attached to the movable pulley of the output pulley in order to apply tension to the belt at the time of shifting or the like. That is, as shown in FIG. 5 and FIG.
A fixed pulley 2 is provided integrally, and a movable pulley 3 is provided movably along the output shaft 1 in opposition to the fixed pulley 2, and a belt is provided between the fixed pulley 2 and the movable pulley 3. In order to apply tension to the belt 4, a torque cam 5 is fixed to the back side of the movable pulley 3, and a right cam surface 5 a of the torque cam 5 is fixed to the output shaft 1. Cam surface 6a of hub 6
And the hub 6 rotates with the rotation of the output shaft 1, so that the cam surface 6 a of the hub 6 comes into sliding contact with the cam surface 5 a of the torque cam 5, and the torque cam 5 and the movable pulley 3
Is pressed toward the fixed pulley 2, whereby tension is applied to the belt 4. However, conventionally, the torque cam 5
The cam surface 5a of the hub 6 and the cam surface 6a of the hub 6 have a large frictional resistance due to metal-to-metal contact, and the dynamic friction coefficient μ of both cam surfaces is μ> tan α in relation to the cam angle α of the cam surface. Therefore, there is a problem that a large thrust is required when moving the movable pulley 3 to the opposite side to the fixed pulley 2.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and has as its object to provide a torque cam mechanism for a continuously variable transmission capable of reducing the thrust during shifting. The gist is that the input is achieved by a belt mounted between a pair of detachable input pulleys attached to the input shaft and a pair of detachable output pulleys attached to the output shaft. In order to transmit the rotation of the shaft to the output shaft by continuously changing the rotation, and to apply tension to the belt,
A torque cam having a cam surface is fixedly provided on an outer surface of the movable pulley in the output pulley, and a hub having a cam surface abutting on the cam surface is attached to the output shaft so as to face the torque cam. In the continuously variable transmission having the torque cam mechanism, the cam surface of one of the torque cam and the hub is provided on each of the peaks of a plurality of projecting pillars projecting at intervals, in the thickness direction. A through-hole is formed in the through-hole, and the resin is filled into the through-hole by injection molding, and a resin for sliding is formed on the surface of the peak.
That is, the chips are formed integrally.

[0004]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of the torque cam 5 and the hub 6 of the present embodiment in a contact state. The torque cam 5 is attached to the movable pulley 3 on the output shaft side of the continuously variable transmission by fixing its flange portion 5c. FIG. 2 shows the torque cam 5 of this embodiment.
A base 5b is formed in a ring shape inside the flange 5c, and three protruding pillars are formed at predetermined intervals on the base 5b. The portions 5d, 5d, 5d are integrally formed so as to protrude, respectively, and cam surfaces 5a, 5a are formed at the tip of each protruding pillar portion 5d in a mountain shape, respectively.

As shown in FIGS. 3 and 4, the cam surface 5a protrudes in the form of a mountain at the tip of the protruding column portion 5d to form a mountain 5e in advance. A through hole 5f penetrating in the direction shown in FIG.
From the state shown in FIG.
The sliding resin chip 7 having a small friction coefficient is integrally formed on the surface of the crest portion 5e as shown in FIG. 2 and FIG. Form the cam surface 5a. The sliding resin chip 7 can be made of, for example, a polyimide-based or phenol-based resin. The resin can be integrated with the surface of the ridge 5e by injection molding at a reduced cost by injection molding. Since it is filled, the sliding resin chip 7 is integrated with the peak 5e and does not come off from the peak 5e.

As described above, since the sliding resin chip 7 is integrated with the peak 5e at the tip of each protruding pillar 5d and the cam surface 5a is formed of the sliding resin chip 7, it is fixed to the output shaft 1. Cam surface 6a having a gentle inclination of hub 6
Since the cam surface 5a at the tip of each protruding column portion 5d abuts and slides, the friction coefficient of the cam surface 5a is small due to the sliding resin chip 7, and the cam surface 5a of the torque cam differs from the conventional cam surface 5a. The sliding contact resistance of the cam surface 6a of the hub 6 does not become large, and the movable pulley 3 can be moved to the fixed pulley 2 in a state where the sliding contact resistance is small.
Further, in this example, a cam surface 5a formed on the torque cam 5
Is not formed over the entire circumference, but is formed only at the tips of the three protruding pillars 5d, 5d, 5d. Instead of sliding contact, the frictional resistance is further reduced, and since there is no flesh between the protruding columns 5d, 5d of the torque cam 5, the entire torque cam 5 is reduced in weight and cost as compared with the conventional case. It can be formed by being formed. Incidentally, the frictional resistance can be reduced by forming the hub 6 side on the cam surface 6a in which the sliding resin chip 7 is similarly integrated.

[0007]

The present invention relates to a belt mounted between a pair of detachable input pulleys attached to an input shaft and a pair of detachable output pulleys attached to an output shaft. According to this, a torque cam having a cam surface is formed on the outer surface of the movable pulley in the output side pulley in order to transmit the rotation of the input shaft steplessly to the output shaft by transmitting the rotation to the output shaft and to apply tension to the belt. A continuously variable transmission provided with a torque cam mechanism in which a hub having a cam surface fixedly provided and abutting on the cam surface so as to face the torque cam is attached to an output shaft, wherein either the torque cam or the hub is provided. One of the cam surfaces is formed with a through hole penetrating in the thickness direction at each crest at the tip of the plurality of protruding pillars protruding at intervals, and filling the resin in the through hole by injection molding, By unites the sliding resin chips are formed on the surface of Kiyama portion can be formed lightweight reduce cost than conventionally is protruded a projected column portion, moreover the projected column section each ridges are integrated sliding resin chips in order to form a cam surface, sliding tree of the tip of the
The cam surface of the grease tip is in sliding contact, and the frictional resistance at the time of sliding contact can be extremely reduced, which has the effect of extremely reducing the thrust when moving the movable pulley. In addition, the cost can be reduced by injection molding, and the sliding resin chip can be integrated with the surface of the peak, and since the resin is filled in the through hole, the sliding resin chip does not come off from the peak. .

[Brief description of the drawings]

FIG. 1 is a perspective configuration diagram showing a contact state between a torque cam and a hub which constitute a torque cam mechanism.

FIG. 2 is a perspective view of a torque cam.

FIG. 3 is a perspective view showing a main part of a torque cam during the manufacturing process.

FIG. 4 is a cross-sectional configuration view of a main part showing a state in which a sliding resin chip is integrated with a peak at a tip of a protruding column of a torque cam.

FIG. 5 is a cross-sectional configuration diagram showing a mounting state of a conventional torque cam mechanism.

FIG. 6 is a perspective configuration diagram showing a contact state between a conventional torque cam and a hub.

[Explanation of symbols]

 Reference Signs List 3 movable pulley 5 torque cam 5a cam surface 5b base 5c flange 5d protruding column 5e mountain 5f through hole 6 hub 6a cam surface 7 sliding resin chip

Claims (1)

(57) [Claims] 1. A belt mounted between a pair of detachable input side pulleys attached to an input shaft and a pair of detachable output side pulleys attached to an output shaft. The speed of the rotation is continuously changed and transmitted to the output shaft.
In addition, a torque cam having a cam surface is fixedly provided on an outer surface of the movable pulley in the output side pulley so as to apply tension to the belt, and a cam that comes into contact with the cam surface so as to face the torque cam. In the continuously variable transmission provided with a torque cam mechanism in which a hub having a surface is attached to an output shaft, a cam surface of one of the torque cam and the hub is provided with a plurality of projecting pillars projecting at intervals. A through hole penetrating in the thickness direction is formed in each peak at the tip of the resin, and the resin is filled in the through hole by injection molding, and a resin chip for sliding is integrated with the surface of the peak. A torque cam mechanism for a continuously variable transmission.