JP2547894Y2 - Tension clutch operating device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tension clutch widely used for small agricultural machines such as walking tractors.

[0002]

2. Description of the Related Art FIG. 6 shows an example of a conventional tension clutch for a walking tractor.

The clutch operating device 1 includes a clutch lever 2
And a hook 3. The clutch lever 2 is
Left and right parallel bases 2a, 2a are pivotally supported by the handle 4. Here, the clutch lever 2 is urged in the direction of arrow B by an elastic member. Here, a protruding piece 2b is provided at one end of the clutch lever 2, and the wire 5 is connected to the protruding piece 2b via a wire fitting. A tension pulley is connected to the other end of the wire 5. The clutch lever 2 has a hole 2c through which the hook 3a passes.

[0004] The hook portion 3 comprises a hook 3a and a support 3b. The support 3b is fixed to the handle 4 and pivotally supports the hook 3a. The hook 3a is urged in the direction of arrow C by an elastic member. A notch 3c is formed on the back surface of the hook 3a.

Next, the operation of the conventional clutch operating device 1 will be described.

In order to engage the clutch, it is necessary to apply tension to the V-belt. This tension is generated by gripping the clutch lever 2 in the direction of arrow D.
When the clutch lever 2 is gripped, the wire 5 connected to the protrusion 2b pulls the tension pulley, and the tension pulley
The tension is generated by pressing the belt. Hook 3 at the same time
a rotates in the direction of arrow E while making contact with the hole 2c on the back surface, and as a result, the edge of the hole 2c engages the notch 3c, and the clutch lever 2 is engaged (FIG. 6). See dashed line). Thereby, even if the gripped hand is released from the clutch lever 2, the clutch lever 2 maintains the gripped state against the elasticity, so that the driving force of the engine can be continuously transmitted to the transmission.

Conversely, when the clutch is disengaged and the driving force of the engine transmitted to the transmission is cut off, the tip of the hook 3a projecting from the hole 2c is pointed by an arrow E.
And the edge of the hole 2c is separated from the notch 3c. As a result, the clutch lever 2 rotates in the direction of the arrow B due to the urging force of the elastic member and returns to the position shown by the solid line, so that the tension of the V-belt by the tension pulley is released and the driving force of the engine can be cut off.

[0008]

As described above, in the conventional clutch operating device 1, once the clutch is engaged, even if the hand is released from the clutch operating device 1, the hook 3
"a" locks and fixes the lever 2, and the walking tractor continues to operate. For this reason, if the worker suddenly separates his / her hands from the handles 4 and 4 due to a fall or the like, the walking tractor runs away and causes an accident. Further, it is not easy to quickly disengage the clutch against the urging force of the elastic member of the hook 3a, and the walking tractor cannot be stopped urgently. Therefore, work safety cannot be improved.

Also, tension is applied to the V-belt,
In order to engage the clutch against the urging force of the elastic member, it is necessary to hold the clutch lever 2 with a strong force. Since the amount of pulling of the wire 5 is determined according to the rotation angle of the clutch lever 2, the on / off of the clutch cannot be reliably performed unless the rotation angle of the clutch lever 2 is designed to be large.
When the rotation angle of the clutch lever 2 is large, it is difficult to grasp.

Therefore, in order to solve the above-mentioned disadvantage, the present invention solves the above problem. The clutch is automatically disengaged when the hand is released from the handle, and the clutch can be maintained in a connected state only by holding lightly. It is an object of the present invention to provide a clutch operating device that can work with the clutch.

[0011]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object, and comprises connecting a shaft pin 23 to an end of a pulling wire 21 for moving a tension pulley 19 to turn on and off a tension clutch. The cam pin 29 is integrally formed with a clutch lever 30 pivotally supported by the handle 25 by slidingly inserting the shaft pin 23 through a longitudinal guide hole 28 provided in the handle 25 in the front-rear direction. Shaft pin 2
3 is brought into sliding contact with the cam portion 29, and the cam portion 29 moves the shaft pin 23 toward the rear end of the guide slot 28, and a small first cam surface F that holds the shaft pin 23. And two cam surfaces G.

[0012]

When the clutch lever 30 is gripped based on the above structure, the first cam surface F formed on the cam portion 29 is
3 is moved toward the rear end along the guide slot 28. As a result, the wire 21 pulls the tension pulley 19, and the tension pulley 19
To put the clutch into the engaged state.

Further, the position of the shaft pin 23 is held by the second cam surface G formed on the cam portion 29, so that the tension pulley 19 continues to press the V-belt 18.

When the hand is released from the clutch lever 30, the shaft pin 23 moves in the guide long hole in the opposite direction while contacting the second cam surface G with the first cam surface F. The pressure on 18 is released and the clutch disengages.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the tension clutch operating device of the present invention will be described below with reference to FIGS.

First, FIG. 1 shows a walking tractor 10. The walking tractor 10 basically includes a clutch operating device 11, an engine unit 12, a transmission unit 13, a working unit 14, a handle unit 16, and a vehicle body frame 17.

The clutch operating device 11 has a V extending between an engine unit 12 and a transmission unit 13.
There is a tension pulley 19 for pressing the belt 18, and the tension pulley 19 is supported by a tension arm 20 (see FIG. 2). Further, the tension arm 20
Is rotatably supported by the vehicle body frame 17.

The tension arm 20 has an elastic member 21a.
The inner wire 21 is connected via the
Is connected to a shaft pin 23 via a rod 22. 2
1b is an outer tube on the outer periphery of the inner wire 21. The shaft pin 23 is inserted through a hollow shaft cylinder 24, and the shaft cylinder 24 moves integrally with the shaft pin 23 while being regulated by the rod 22 at one end and a washer at the other end.

A grip 26 of a handle 25 to be described later
A perforated plate 27 formed in the shape of a plate is disposed in the vicinity of the plate, and the perforated plate 27 is formed with a guide elongated hole 28 through which the shaft cylinder 24 is inserted. A cam portion 29 for slidably pulling the shaft cylinder 24 in the guide slot 28 is formed integrally with the clutch lever 30,
The clutch lever 30 is pivotally supported on the handle 25. The clutch lever 30 has a substantially U-shaped cross section. The cam portion 29 formed on the clutch lever 30 has a first cam surface F that pulls the barrel 24 and a narrow second cam surface G that holds the position of the barrel 24. At the end of the clutch lever 30, a stopper 31 slightly higher than the U-shaped surface is provided. Further, the finger hanging lever 32 is projected outward (see FIGS. 3 and 4).

The engine section 12 is mounted on the vehicle body frame 17 and has a drive shaft 33 for transmitting a driving force of the engine.
And an engine pulley 34 fixed to the drive shaft 33 (see FIG. 2).

The transmission unit 13 includes an input shaft 3
The input shaft 35 is fixed to the input shaft pulley 36.
Further, a V-belt 18 is stretched between the engine pulley 34 and the input shaft pulley 36.

The working unit 14 is provided below the vehicle body frame 17 and has a rotatable axle 37 that receives driving force from the transmission unit 13. The rotary 15 is fixed to the axle 37 radially.

The handle portion 16 is disposed diagonally above the vehicle body frame 17 and has a pair of handles 25,25. Handles 26, 26 are fixed to the distal ends of the handles 25, 25.

Next, the operation of the tension clutch operating device according to the present embodiment will be described.

When the clutch is disengaged, the V-belt 1 between the engine pulley 34 and the input shaft pulley 36
8 is stretched without tension, and the driving force of the engine is not transmitted to the transmission unit 13.

When the clutch lever 30 is grasped from this state, the first cam surface F moves the shaft cylinder 24 along the guide slot 28 in the direction of arrow H. When the stopper 31 is gripped until it comes into contact with the grip 26, the second cam surface G holds the barrel 24 (see the chain line in FIGS. 3 and 5). This stopper 31 is grip 2
In the state where the clutch lever 30 is fully gripped until it comes into contact with the clutch lever 6, the cam mechanism of the second cam surface G causes the clutch lever 3 to move.
The force to hold 0 may be weak. At this time, the wire 21 is pulled through the shaft pin 23. And tension arm 2
0 moves upward, and the tension pulley 19
8 is tensed, and the driving force of the engine is transmitted to the transmission unit 13.

The driving force transmitted to the transmission unit 13 is transmitted to the working unit 14. In the working unit 14, the rotary 15 rotates to advance the walking tractor 10 and tilling the ground.

To release the clutch, the clutch lever 30
Release your hand from As a result, the clutch lever 30 is restored by the urging force of the elastic member, and the shaft cylinder 24 moves in the direction of arrow I along the guide slot 28. As a result, the tension arm 20 moves downward, the tension pulley 19 is disengaged from the V-belt 18, the clutch is disengaged, and the rotation of the rotary 15 stops.

As described above, according to the present embodiment, the cam portion 29 formed in the clutch lever 30 and the guide slot 28 formed in the perforated plate 27 hold the clutch lever 30 to pull the pulling wire. Thus, the clutch can be operated with a small rotation angle of the clutch lever 30, and the user does not get tired even if he or she holds the clutch continuously. When the hand suddenly leaves the clutch lever 30 or when it is necessary to immediately release the clutch, the clutch is automatically released by releasing the clutch lever 30. Further, when the clutch is forcibly disengaged, the finger hook lever 32
It is also possible to disengage the clutch by applying a downward force to the clutch.

[0030]

[Effects of the Invention] As described above, according to the present invention,
With the first cam surface of the cam portion formed on the clutch lever and the guide elongated hole, the clutch can be easily operated by slightly rotating the clutch lever.

Further, the second cam surface can maintain the state in which the clutch lever is held with a weak force, so that work can be continued for a long time with a small effort. Further, when the hand suddenly leaves the clutch lever or when it is necessary to immediately release the clutch, the clutch is automatically released by releasing the hand from the clutch lever, so that the operation can be performed safely.

[Brief description of the drawings]

FIG. 1 is a side view of a walking tractor according to an embodiment of the present invention.

FIG. 2 is a side view of the tension clutch of FIG.

FIG. 3 is an enlarged side view of a main part of FIG. 1;

FIG. 4 is a plan view of FIG. 3;

FIG. 5 is a perspective view of a clutch lever.

FIG. 6 is a side view of a conventional clutch lever.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Walking type tractor 18 V belt 19 Tension pulley 20 Tension arm 21 Wire 23 Axis pin 24 Axis cylinder 27 Perforated plate 28 Guide slot 29 Cam part 30 Clutch lever F 1st cam surface G 2nd cam surface

Claims (1)

(57) [Scope of request for utility model registration] 1. A shaft pin is connected to a terminal of a pulling wire for moving a tension pulley to turn on and off a tension clutch, and the shaft pin is slidably inserted into a longitudinal guide hole provided in a handlebar. Then, a cam portion is integrally formed with a clutch lever pivotally supported by the handle, and the shaft pin is slidably contacted with the cam portion. The cam portion moves the shaft pin toward a rear end of the guide elongated hole. A tension clutch operating device comprising a first cam surface and a narrow second cam surface for holding a shaft pin.