JP2005042908A - Self-displacement control of pulley diameter for v belt type continuously variable transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems in the speed change drive control of a conventional V-belt type continuously variable transmission, wherein as constitutions of a load detecting mechanism and a gear shift ratio setting mechanism, or an electronic control circuit and an adjustment driving mechanism are necessary, it is unsuitable to be fitted in a compact industrial machine, automobile, motorcycle and bicycle, and further electricity and oil-pressure supply sources are necessary to drive a control mechanism in a constitution of a conventional V belt type continuously variable transmission mechanism. <P>SOLUTION: In this V belt type continuously variable transmission mechanism, a clearance between pulleys divided into a power side and a load side is changed on the basis of the balance of the screw-like engagement and the force of a spring mounted between a shaft 1 or 8 and the pulleys 3, 4 or 10, 11 by allowing the rotating torque generated between the shaft and pulley at the power side and load side in accordance with the change of the power torque or load torque, to directly act, whereby the diameters of the pulleys at the power side and the load side are changed, and the self-displacement is controlled in the V belt type continuously variable transmission. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a shift control means for a V-belt transmission mechanism mounted on an industrial machine, automobile, motorcycle or bicycle that requires a power transmission.

  By using a V-belt type continuously variable transmission mechanism for transmission of power to industrial machines and automobiles, it does not give a large load fluctuation to the power side like stepped transmission, and requires a large power source. It is possible to transmit and shift power efficiently.

  However, the load detection mechanism, the gear ratio setting mechanism, the electronic control circuit, the adjustment drive mechanism, etc. are used for the displacement control of the pulley distance divided in order to change the pulley diameter in the speed change control of the conventional V belt type continuously variable transmission. In order to drive these mechanisms, an electric power source and a hydraulic power source were necessary.

The conventional shift drive control of the V-belt type continuously variable transmission requires several mechanisms such as a load detection mechanism, a gear ratio setting mechanism, an electronic control circuit, and an adjustment drive mechanism. Or it was unsuitable for mounting on motorcycles and bicycles. In order to construct a conventional V-belt type continuously variable transmission mechanism, an electric supply source and a hydraulic supply source are required for driving the control mechanism.
Especially in the case of bicycles, it is impossible to install such a stepless speed change control mechanism, so a stepped speed change mechanism using a chain and gear is adopted. Since it is necessary to frequently change gears according to the degree of climbing up and down the hill, it is very troublesome, and if you do not switch the gear stage, the power to step on the pedal is too light or too heavy, Extra kinetic energy was spent. Moreover, even if the gear stage was switched appropriately, the weight of stepping on the pedal changed step by step, putting stress on the rider.

  In the V-belt type continuously variable transmission mechanism, the power and load side shafts and pulleys are changed according to the change of the power torque from the prime mover according to the intention of the driver and the load torque according to the load side situation. By directly using the rotational torque generated in step 1, the distance between the two pulleys for changing the pulley diameter on the power side and the load side is displaced, thereby controlling the stepless speed change by changing the pulley diameter.

A large-scale mechanism such as a load detection mechanism, a gear ratio setting mechanism, an electronic control circuit, and a halved pulley interval adjustment mechanism for changing the pulley diameter is not required in the shift control of the V-belt type continuously variable transmission. In addition, it can be mounted on industrial machines, automobiles, motorcycles and bicycles, and an electric or hydraulic supply source for driving these mechanisms becomes unnecessary.
Therefore, it is possible to mount a V-belt type continuously variable transmission on a bicycle, and when this is configured, the transmission gears must be manually and frequently switched according to the degree of speed increase / decrease and up / down slope. Not only does it have to be done, but only by speeding up the pedal, you can accelerate and climb the hill without changing the weight of the pedal. It automatically shifts to a gear ratio that requires less pedal rotation.
Further, a mechanism for changing the position of the chain surrounding the gear, such as a stepped transmission, is not required.

  The power side and load side shafts and pulleys of the V-belt type continuously variable transmission mechanism are not fixed, and screw-like grooves and projections having a certain direction and a certain angle, such as bolts and nuts, are provided on the joint surfaces of the shaft and the pulleys. On the power side, a tension coil spring (5) is provided to apply a force to narrow the distance between the two pulleys (3) and (4). On the load side, a force to increase the distance between the two pulleys (10) and (11) is applied. The compression coil spring (12) is provided.

In the power-side control mechanism, in the state where the screw-like protrusions inside the pulleys (3) and (4) opposite to the screw-like guide grooves (2) provided on the power-side rotating shaft (1) in FIG. The load on the power side pulley (3) (4) is increased by increasing the rotational torque of the power side rotating shaft (1) to increase the side rotation speed or by increasing the load on the belt from the load side. In this case, the torque generated between the power side rotating shaft (1) and the pulleys (3) and (4) increases.
For this reason, the pulleys (3) and (4) divided into right and left along the guide groove (2) meshing with the screw shape move in the opposite direction to the force acting on the tension coil spring (5) on the shaft, The distance between the pulleys (3) and (4) divided into two on the left and right is increased, and the outer diameter of the belt surrounding the pulley is reduced. As a result, the belt position shown in FIG. 1 (6) is reached when the load torque and / or power torque is maximum, and the state of the belt when the entire transmission mechanism is viewed is as shown in FIG.
On the contrary, when the rotational torque of the power side rotating shaft (1) is reduced or the load on the power side pulley (3) (4) is reduced due to the load applied to the belt from the load side being reduced. The left and right pulleys (3) and (4), which are divided into two left and right pulleys by the force of the tension coil spring (5) provided between the left and right pulleys (3) and (4), move and return on the shaft. (3) The interval between (4) is narrowed, and the diameter surrounding the belt as a pulley is increased. As a result, when the load is maximum, the belt position shown in FIG. 2 (7) is obtained, and the state of the belt when the entire transmission mechanism is viewed is as shown in FIG. 6 (17).

In the load side control mechanism, in FIG. 3 the state where the screw-like protrusions inside the pulleys (10) and (11) opposite to the load shaft screw-like guide groove (9) provided on the load-side rotating shaft (8) are engaged. When the load applied to the load side rotating shaft (8) increases or the power from the power side transmitted by the belt increases, the torque generated between the load side rotating shaft (8) and the pulleys (10) (11). Becomes larger. For this reason, the pulleys (10) and (11) divided into two on the left and right along the guide groove (9) meshing with the screw shape move on the shaft in the direction opposite to the force acting by the compression coil spring (12). As a result, the distance between the pulleys (10) and (11) divided into the left and right parts is reduced, and the outer diameter of the belt as the pulley is increased. As a result, the belt position (13) is reached when the load torque and / or power torque is maximum, and the state of the belt when viewing the entire transmission mechanism is as shown in FIG. 5 (17).
On the other hand, when the load applied to the load side rotating shaft (8) is reduced or the power from the power side transmitted by the belt is reduced, the load side rotating shaft (8) and the pulley (10) (11 ) Between the left and right pulleys (10) and (11), the pulleys (10) and (11) divided into two left and right by the force of the compression coil spring (12) provided on the shaft The distance between the left and right pulleys (10) and (11) is increased by movement, and the diameter of the belt surrounding the pulley is reduced. As a result, when the load is maximum, the belt position shown in FIG. 4 (14) is obtained, and the state of the belt when the entire transmission mechanism is viewed is as shown in FIG.

  When the distance between the power side left and right pulleys (3) and (4) and the load side left and right pulleys (10) and (11) are balanced at a constant distance and the diameter of the pulley around the power side belt is large, When the diameter of the pulley surrounding the belt is small, and when the diameter of the pulley surrounding the power belt is small, the diameter of the pulley surrounding the load belt is large. The tension of the belt does not change, but when the torque of the power side rotating shaft (1) suddenly increases, the outer diameter of the belt of the power side pulley is reduced in advance, so the belt tension is kept constant. A pulley (15) having a force for pulling the belt inward by a tension coil spring is provided.

  Further, in order to make the movement distance of the left and right pulleys equally divided, a rod (16) for synchronizing the rotation of the left and right pulleys is provided. Either one of the left and right pulleys is fixed to the pulley, while the other is not fixed so that the pulley can move in the direction of the rotation axis. The same applies to the power side and the load side.

  In the shift control of the V-belt type continuously variable transmission, a large-scale mechanism such as a load detection mechanism, a gear ratio setting mechanism, an electronic control circuit, and a two-way pulley interval adjustment mechanism is not required. Alternatively, a V-belt continuously variable transmission mechanism can be used for motorcycles and bicycles.

State of power side cross section when torque between power side rotating shaft and pulley is large State of power side cross section when torque between power side rotating shaft and pulley is small State of load side cross section when torque between load side rotating shaft and pulley is large State of load side cross section when torque between load side rotating shaft and pulley is small V-belt condition when power torque or load torque or both are large V-belt condition when power torque or load torque or both are small

Explanation of symbols

1 Power side rotating shaft 2 Power shaft screw guide groove 3 Power side pulley left half (cross section)
4 Power side pulley right half (cross section)
5 Tension coil spring 6 Power V-belt position (cross section) when torque is large
7 Position of power side V-belt when torque is small (cross section)
8 Load side rotating shaft 9 Load shaft screw guide groove 10 Load side pulley left half (cross section)
11 Load side pulley right half (cross section)
12 Compression coil spring 13 Load side V-belt position (cross section) when torque is large
14 Position of load side V-belt when torque is small (cross section)
15 Belt tension adjusting pulley 16 Rod that synchronizes one rotation of left and right pulleys 17 V belt (cross section)

Claims (1)

  In a V-belt type continuously variable transmission mechanism, a machine that uses rotational torque generated between a power-side and load-side pulley and shaft in accordance with the magnitude of power torque from a motor or manpower and the magnitude of load torque By directly controlling the distance between the pulverized pulleys on the power side and the load side by self-displacement, the diameters of the pulleys on the power side and the load side are changed to control the stepless speed change.

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