JPH0217744B2 - - Google Patents

Description

[Detailed Description of the Invention] Conventionally, a continuously variable transmission device in which a V-belt is stretched between a pair of split pulleys operates manually or hydraulically a cam attached to a movable pulley of one split pulley to change the width of the split pulley. The speed was changed by expanding and contracting the cam, but this required a large amount of operating force due to the resistance on the sliding surface of the cam, and it also suffered from wear and tear, resulting in low durability. Furthermore, when the movable pulley of the split pulley is moved forward and backward using a screw, the threaded portion slides unsmoothly, making it difficult to change gears when a load is applied to the split pulley.

The present invention aims to improve the above-mentioned drawbacks, and is directed to a split-pulley type continuous transmission device in which a split pulley is installed on a shaft supported by a transmission case. A male threaded tube that does not move in the axial direction but rotates is installed, a female threaded tube screwed onto the male threaded tube is supported so that it does not rotate but moves in the axial direction, and a motor is linked to the male threaded tube. The inner periphery of the male threaded cylinder is connected to the inside of the transmission case through an oil passage, and a hole is bored in the male threaded cylinder so that the speed can be continuously changed by forward and reverse rotation of the motor. The present invention is characterized in that the lubricating oil is applied to the threaded portions of the male and female screw tubes.

The embodiments shown in the drawings will be explained below.
A V-belt 6 is attached to the pulley 2 of the engine 1 and the V-pulley 5 attached to the shaft 4 of the counter gear case 3.
The continuously variable transmission consists of a V-belt 10 stretched between a driving split pulley 7 attached to the shaft 4 and a driven split pulley 9 attached to the input shaft of the traveling transmission 8. Reference numeral 7 is composed of a fixed pulley 7a that rotates integrally with the shaft 4, and a movable pulley 7b that slides in the axial direction. A female threaded cylinder 1 is rotatably mounted on the boss portion of the movable pulley 7b via a bearing so as not to move laterally.
A rotary arm 15 of a servo motor 14 is interlocked with the end of a pin 13 fixed to the male threaded cylinder 11. The supporting frame 17 has a guide groove 18 parallel to the shaft 4 in its upper part, and a sliding piece 19 protruding from the upper surface of the female threaded cylinder 12 is loosely fitted into the guide groove 18.

Further, a speed control dial 21 is provided on the top plate of the operation panel 20 of the combine, and a pair of limit switches 22, 22 are attached to the inner peripheral surface of the lower part of the speed control dial 21, and are placed close to and directly below the speed control dial 21. The provided rotary plate 26 has a support shaft 23 rotatably supporting the speed control dial 21 at its center, and a pair of arcuate contact pieces 24, 24 corresponding to the limit switches 22, 22.

Further, since a spring 25 attached to the lower surface of the top plate is engaged with a large number of recesses provided on the outer periphery of the lower part of the speed control dial 21, the speed control dial 21 can be rotated and stopped at a desired position, and the limit switch can be activated. The code 27 of 22, 22 is connected to the control circuit, and also to the servo motor 14.
The cord 28 is connected to a power source.

The inner circumferential surfaces of the fixed pulley 7a and the movable pulley 7b and the threaded engagement portions include an oil passage 29,
Since it communicates with the inside of the counter gear case 3 through the holes 31 and 32, the oil in the counter gear case 3 is applied to the sliding parts of the pulleys 7a and 7b and the shaft 4, and the engaging part of the screw.

Furthermore, the rack 33 attached to the sliding piece 19 meshes with a pinion 34 that is pivotally supported on the support frame 17, and the pinion 34 is connected to the support shaft 23 of the rotary plate 26 by a wire 35.

In addition, in the drawing, 36 is a scale plate, and 37 is an oil seal.

In the above-mentioned device, the contact pieces 24, 24 are opposed to each other on the diameter of the speed control dial 21, while the limit switches 22, 22 are displaced to one side and face each other, and the speed control dial 21 is shown in FIG. As shown by the solid line, one limit switch 22 is ON and the other limit switch 2 is ON.
2 is off, the servo motor 14 is stopped and both limit switches 22, 22 are turned off.
When both are turned on, the servo motor 14 rotates in the speed increasing direction, and the speed control dial 2
1 and both limit switches 22, 22 are connected to contact piece 2.
When the servo motor 14 is set so as to be turned OFF away from 4 and 24, the servo motor 14 rotates in the deceleration direction.

When the servo motor 14 rotates in this way, the male threaded tube 11 rotates the rotating arm 15 and the pin 13,
As the female threaded cylinder 12 moves along the guide groove 18, the rack 33 rotates the pinion 34, and the pinion 34 connects one of the limit switches 22 (or 22) via the wire 35 and the support shaft 23. ) is turned OFF.
When rotating 6, the servo motor 14 stops,
Eventually, the speed is changed to the speed set by the speed control dial 21.

The present invention provides a split-pulley type continuous transmission device in which a split pulley is installed on a shaft supported by a transmission case as described above, in which a male threaded cylinder is mounted on the shaft of the split pulley, but does not move in the axial direction, but rotates. and supporting the female threaded cylinder screwed onto the male threaded cylinder so that it does not rotate but moves in the axial direction,
A motor is interlockingly connected to the male threaded tube and the speed is continuously variable by forward and reverse rotation of the motor, an inner periphery of the male threaded tube is communicated with the inside of the transmission case through an oil passage, and a hole is bored in the male threaded tube. The lubricating oil in the transmission case is applied to the threaded parts of the male and female threaded cylinders, so that when the motor is rotated in either direction, the male threaded cylinder moves the movable pulley together with the female threaded cylinder. V of split pulley
By expanding and contracting the grooves, it is possible to obtain a continuously variable transmission device that does not require a large operating force unlike the conventional ones, does not wear out the cam, and has excellent operability and durability.

In addition, the means for moving the movable pulley is rotated by a male threaded tube fitted around the outer periphery of the shaft.
Furthermore, since we adopted a method in which the female threaded cylinder screwed onto the outer periphery moves in the axial direction, the movable pulley can be pushed and pulled at a greater distance from the axis than with a method in which a screw is screwed onto the inner periphery of the movable pulley. This makes it possible to easily operate the movable pulley at variable speeds even under load.

Furthermore, since the threaded portions of the male and female threaded tubes can be lubricated, the rotation of the male threaded tube and the movement of the female threaded tube can be extremely easily performed even during transmission.

[Brief explanation of drawings]

The drawings show one embodiment of the invention,
Fig. 1 is a plan view of the transmission, Fig. 2 is a side view of the main parts, Fig. 3 a is a partially cutaway front view of the same, b is a plan view of the drive section of the speed control dial, Fig. 4 is Fig. 5 is a plan view of the switch section, Fig. 5 is a sectional view of the speed control section, Fig. 6 is a plan view of the speed control dial, Fig. 7 is a plan view of the dial locking section, and Fig. 8 is a perspective view of the control section. be. 7a...Fixed pulley, 7b...Movable pulley, 11...Male thread tube, 12...Female thread tube, 14
... Servo motor, 15 ... Guide groove, 19 ...
Sliding piece, 22...Limit switch, 21...Speed control dial, 24...Touch piece.

Claims (1)

[Claims] 1. In a split-pulley type continuously variable transmission device in which a split pulley is attached to a shaft supported by a transmission case, a male threaded tube that does not move in the axial direction but rotates is attached to the shaft of the split pulley, and the male threaded tube rotates. A female threaded cylinder screwed into the cylinder is supported so that it does not rotate but moves in the axial direction, and a motor is interlockingly connected to the male threaded cylinder so that the speed is continuously variable by forward and reverse rotation of the motor. The inner periphery of the transmission case is configured to communicate with the inside of the transmission case through an oil passage, and a hole is bored in the male threaded cylinder so that lubricating oil in the transmission case is applied to the threaded portion of the male and female threaded cylinders. Continuously variable transmission featuring.