JPH0122996Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a variable speed V-pulley used in a belt type continuously variable transmission and the like.

Conventional variable speed V-pulleys, in which a movable conical plate is disposed opposite to a fixed conical plate so as to move toward and away from each other while being constantly pressed and energized by an external compression coil spring, have an external compression coil spring. Due to the structure, there are certain restrictions on the part where it is attached, so the effective number of turns cannot be large, and there is a large difference in the pressure (elastic force) when the spring expands and contracts, so there is a large difference in the clamping force of the variable speed V-belt. When the clamping force is strong, there is a noticeable decrease in mechanical efficiency and shortening of the life of the variable speed V-belt, and when it is weak, slipping occurs, which is a fatal drawback. Since the pressure corresponding to the load torque is directly applied, the rigidity of the key and the frictional force with the key groove become large, which also has the disadvantage of increasing key wear and sliding resistance.

This device biases the movable conical plate toward the fixed conical plate by means of tension springs installed between these bosses, and imparts torsional elasticity to the anti-load side to the tension springs. The object of the present invention is to obtain a variable speed V-pulley that eliminates the drawbacks of the above.

That is, the variable speed V-pulley according to this invention has a movable conical plate facing a fixed conical plate so as to be able to move toward and away from the fixed conical plate, and a tension spring is interposed between the boss portion of the fixed conical plate and the boss portion of the movable conical plate. By applying a tensile force to the movable conical plate toward the fixed conical plate, the tension spring can be a spring with a large number of effective windings covering almost the entire length of the variable speed V-pulley. The pressure difference is small, resulting in efficient gear shifting operation, and
Since the tension spring is an internal type inserted in the gap between the boss part of the fixed conical plate and the boss part of the movable conical plate, there is no loss of balance during high-speed rotation, and the variable speed V-pulley can be made smaller. By imparting torsional elasticity to the anti-load side of the tension spring, the rigidity of the key and the frictional force with the keyway are reduced, reducing key wear and sliding resistance by half, resulting in smooth, reliable and durable gear shifting operations. It also improves the

The variable speed V-pulley according to this invention will be explained in detail below based on the drawings. In the drawings, reference numeral 1 denotes a fixed conical plate, and a bottomed cylindrical boss portion 3 protruding from one side of the fixed conical plate.
is fixed to one end of the rotating shaft 6 to integrally connect the fixed conical plate 1 with the rotating shaft 6. Reference numeral 2 denotes a movable conical plate, and a cylindrical boss portion 4 protruding from one side of the plate is fitted onto the rotating shaft 6 via a fixed key 7, so that the movable conical plate 2 is fixed in the rotating direction with respect to the rotating shaft 6. It is fitted so that it can freely slide in the axial direction and is opposed to the fixed conical plate 1 so as to be able to come into contact with and separate from it. The outer diameter of the cylindrical boss portion 4 of the movable conical plate 2 is smaller than the inner diameter of the bottomed cylindrical boss portion 3 of the fixed conical plate 1. A gap a is formed between the two for inserting a tension spring 5, which will be described later. Reference numeral 5 denotes a tension spring interposed in a gap a formed between the bottomed cylindrical boss portion 3 of the fixed conical plate 1 and the cylindrical boss portion 4 of the movable conical plate 2 over substantially the entire length of the variable speed V pulley; One free end 5a
is fixed to the bottomed cylindrical boss portion 3 of the fixed conical plate 1, and the other free end 5b is fixed to the movable conical plate 2, thereby applying a tensile force to the movable conical plate 2 toward the fixed conical plate 1. When installing the above tension spring 5,
When the tension spring 5 is wound up to provide torsional elasticity in the opposite direction of load (in the opposite direction of rotation), the load torque applied to the fixed key 7 is halved. Reference numeral 8 denotes a variable speed V-belt hooked on the V-groove of a variable-speed V pulley formed by a stationary conical plate 1 and a movable conical plate 2 facing each other, and constantly maintains a constant side pressure by the pinching force of the tension spring 5. . Reference numeral 9 denotes a mounting hole drilled in the center of one side of the rotating shaft 6, and is for mounting on a rotational drive shaft such as a motor shaft or a driven shaft on a machine side or the like.

In the above configuration, since the tension spring 5 is interposed over almost the entire length of the variable speed V-pulley consisting of the fixed conical plate 1 and the movable conical plate 2, its effective number of turns increases, and therefore, the pressure difference due to its expansion and contraction increases. is small, and the overhang of the running line of the speed change V-belt 8 is also reduced. Further, since the tension spring 5 is of an internal type, there is no loss of balance due to vibrations etc. during high speed rotation. Therefore, when the movable conical plate 2 approaches and separates from the fixed conical plate 1 due to a change in the pitch diameter of the variable speed V-belt 8, the variable speed V-belt 8 maintains a constant lateral pressure due to the tensile force of the tension springs 5. I will follow it as it is. Furthermore, if the tension spring 5 is given torsional elasticity in the opposite direction to the load side, the load torque applied to the fixed key 7 will be subtracted by that amount with the help of the torsional elasticity, so key wear and sliding resistance will be reduced. It is.

As explained above, this device applies a tensile force to the movable conical plate toward the fixed conical plate by means of a tension spring interposed between the boss portion of the fixed conical plate and the boss portion of the movable conical plate, and It has a simple structure in which the tension spring is given torsional elasticity toward the anti-load side.
It is possible to always equalize the side pressure on the speed change V-belt, increase its life, and reduce the load torque applied to the key by half to ensure smooth and reliable speed change operation, as well as downsize the speed change V-pulley and improve its durability. effective.

[Brief explanation of drawings]

FIGS. 1 and 2 are cross-sectional views of the variable speed V-pulley according to this invention in an operating state. 1... Fixed conical plate, 2... Movable conical plate, 3...
Boss part of fixed conical plate, 4...Boss part of movable conical plate, 5...Tensile spring.

Claims (1)

[Scope of utility model registration request] In a variable speed V-pulley in which a movable conical plate 2 is arranged so as to be able to approach and separate from a fixed conical plate 1, a spring mounting gap is formed between a boss portion 3 of a fixed conical plate 1 and a boss portion 4 of a movable conical plate 2. A variable speed V-pulley characterized in that a tension spring 5 is interposed on the anti-load side with torsional elasticity.