JPH0545855Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention is a so-called synchronous engagement friction clutch installed on the drive shaft for driving working machinery for power agricultural machinery equipped with a prime mover, such as agricultural tractors and rice transplanters. ,
The present invention relates to a synchronous engagement friction clutch suitable as a PTO clutch, that is, one integrally configured with a dog clutch and a friction brake that reduces the speed difference between both shafts prior to engagement of the dog clutch.

[Conventional technology]

In general, dog clutches have the advantage of being able to transmit large amounts of power without slipping, but they have the disadvantage of generating large impacts when engaged. Conventionally, therefore, the speeds of the drive shaft and the driven shaft are synchronized prior to engagement of the dog clutch.

That is, a friction clutch operated by a unique hydraulic cylinder is provided in parallel with the dog clutch, and the friction clutch is operated prior to the operation of the dog clutch.
-Publication No. 5884).

(Problems to be solved by the invention) However, simply adding a friction clutch to a dog clutch would complicate the configuration, and providing hydraulic cylinders individually would complicate the configuration, requiring control means and the number of parts. Furthermore, there is a problem that increases manufacturing costs excessively.

[Means for solving problems]

The purpose of this invention is to solve the above-mentioned problems and to provide a device that has a simple structure and can be manufactured at low cost in order to reduce the shock when the dog clutch is engaged. 2
A clutch member 7 having a wider width is slidably and loosely fitted around the outer periphery of a flange 6 provided on the driven shaft 3, and the pivoting friction plate 4 and the clutch are engaged with the input shaft 2. A pressure receiving plate 8 provided at the outer end of the clutch member 7 and a driven friction plate 5 engaged with the member 7
and a hydraulic piston 9 provided on the inner surface of the flange 6 to form a friction clutch that is pressed and frictionally engaged between the external teeth 6a provided on the outer periphery of the flange 6 and a hydraulic piston 9 provided on the other end of the clutch member 7. In the case where the clutch 10 is engaged with the internal teeth 7c and configured to be freely engaged and disengaged, a locking mechanism 11 is provided between the outer periphery of the flange 6 and the clutch member 7 to loosely lock both when the piston 9 is in the retracted position. It is characterized by the fact that

[Effect]

When the piston 9 moves forward and presses both the friction plates 4 and 5, the axial movement of the clutch member 7 is locked until the magnitude of the reaction force exceeds the set load of the locking mechanism 11, and the meshing clutch 10 engagement is inhibited. Therefore, the speed difference between the friction plates 4 and 5 before the dog clutch 10 is engaged is rapidly reduced.

Next, when the action of the piston 9 exerts a force to release the locking mechanism 11, the piston 9
moves the clutch member 7 via both friction plates 4, 5 and the pressure receiving plate 8. Then, the meshing clutch 10 is rapidly engaged by utilizing the slight speed difference between the two shafts 2 and 3. [Embodiment] This invention will be explained below with reference to the illustrated embodiment. Number 1 is a PTO clutch for an agricultural tractor. The PTO clutch 1 is configured to receive engine power from an input shaft 2 formed in the shape of a gear, and to output power from a driven shaft 3 that pivotally supports the input shaft 2. That is, the PTO clutch 1 consists of a dog clutch 10 that connects and releases the input shaft 2 and the driven shaft 3, and a friction clutch for smoothly engaging the dog clutch 10 connects the input shaft 2 and the driven shaft 3. It is interposed between the driven shaft 3 and the dog clutch 10, and is constructed integrally with the dog clutch 10.

First, the meshing clutch 10 has spline-shaped external teeth 6a provided on the outer periphery of a flange 6 integrally formed with the driven shaft 3, and internal teeth 7 that mesh with the spline-shaped external teeth 6a.
It is composed of c. That is, a wider clutch member 7 is provided on the outer periphery of the flange 6 so as to be slidable in the axial direction, and the inner tooth 7c is formed on the inner surface of the clutch member 7. Therefore, the dog clutch 10 is engaged when the clutch member 7 moves to the left in the figure, and is disengaged when the clutch member 7 moves to the right.

A piston 9 is used to operate the clutch member 7, and is slidably fitted into a cylinder hole 6a formed on the inner surface of the flange 6. piston 9
is pushed to the left by pressure oil sent into the cylinder hole 6c through the oil passage 3a, thereby engaging a friction clutch to be described later. Reference numeral 14 denotes a return spring that presses the piston 9 into the cylinder hole 6a, and also pushes the flange step 7 provided at the outer end of the piston 9.
Press e to move the clutch member 7 to the right in the figure and release the engagement of the dog clutch 10.

Here, the clutch member 7 is provided with a large number of slits 7b in a portion 7a projecting outward from the flange 6, in which the driven friction plate 5 is inserted into the protrusion 5 on the outer periphery.
They are engaged by a. Further, a cylindrical gear extending inward of the clutch member 7 is integrally formed on the input shaft 2, and a drive friction plate 4 is provided therein.
is locked so that it can move only in the axial direction. The driving friction plates 4 and the driven friction plates 5 are arranged alternately and installed between the pressure receiving plate 8 and a pressing plate formed of a flange formed on the piston 9.

In this invention, the dog clutch 10
A locking mechanism 11 is interposed between the internal teeth 7c and the external teeth 6a. The locking mechanism 11 temporarily locks the flange 6 and the clutch member 7 when the piston 9 is in the retracted position.
and an inner circumferential groove 7d provided on the inner surface of the clutch member 7,
and an occluded ring 12 fitted in the outer circumferential groove 6b, and the occluded ring 12 is simultaneously engaged with the outer circumferential groove 6b and the inner circumferential groove 7d when the clutch member 7 is in the position where it engages and interrupts the clutch 10. together,
The relationship between the two is maintained immovably until an actuation force greater than expected is applied to the clutch member 7.

Next, the operation of this embodiment will be explained. In Figure 1, the upper half shows the disengaged state of the clutch.
The piston 9 is moved into the cylinder hole 6 by the return spring 14.
c, and the dog clutch 10 is also kept in a disengaged state. To shift the PTO clutch 1 to the engaged state while the input shaft 2 is in operation, pressure oil is supplied into the cylinder hole 6a from the oil passage 3a. As a result, the piston 9 moves forward against the return spring 14,
The friction plates 4 and 5 are compressed. This allows input shaft 2
rotation is transmitted to the driven shaft 3, and the speed difference between both shafts is reduced. At this time, the clutch member 7 is attached to the locking mechanism 1.
1, the clutch member 7 is prevented from moving in the axial direction until the pressing reaction force by the piston 9 exceeds the set load, and the dog clutch 10 is held in the disengaged state. The lower half of Figure 1 shows this state.

When the reaction force of the piston 9 reaches a level that releases the locking mechanism 11, the piston 9 moves against both the friction plates 4,
5, and the clutch member 7 is moved to the left via the pressure receiving plate 8. Then, by utilizing the fact that a slight speed difference remains between the two shafts 2 and 3, the meshing clutch 10 is smoothly and rapidly engaged.

Needless to say, clutch dissociation occurs through the reverse process.

[Effect of idea]

As described above, this invention only requires a few mechanical parts to be attached to the engaging clutch, and prior to engagement, the movement of the engaging teeth is temporarily stopped by the locking mechanism 11, and the friction brake is operated. The purpose is to synchronize the speeds of the input shaft 2 and the driven shaft 3 by creating time for the friction clutch and the driven shaft 3. Therefore, unlike the conventional method, the locking mechanism 11 is not provided, and hydraulic devices are provided separately for the friction clutch and the meshing clutch. The structure is simpler than that of
Since it is possible to engage and disengage smoothly and reliably in the same manner as before, it has a significant practical effect.

[Brief explanation of the drawing]

The drawings show an embodiment of this invention; FIG. 1 is a sectional view of a synchronous engagement friction clutch, and FIG. 2 is an enlarged front view showing the main parts thereof. 2... Input shaft, 3... Driven shaft, 10... Dog clutch, 11... Locking mechanism, 12... Missing ring, 14... Return spring.

Claims (1)

[Claims for Utility Model Registration] (1) The input shaft 2 is rotatably fitted on the driven shaft 3,
A wider clutch member 7 is slidably loosely fitted around the outer periphery of a flange 6 provided on the driven shaft 3, and the drive friction plate 4 engaged with the input shaft 2 and the driven friction plate 7 engaged with the clutch member A friction clutch is formed in which the dynamic friction plate 5 is pressed and frictionally engaged between a pressure receiving plate 8 provided at the outer end of the clutch member 7 and a hydraulic piston 9 provided on the inner surface of the flange 6. External teeth 6 provided on the outer periphery of
a and internal teeth 7c provided at the other end of the clutch member 7 to engage and disengage the clutch 10, in which there is a gap between the outer periphery of the flange 6 and the clutch member 7 when the piston 9 is in the retracted position. A synchronous engagement friction clutch provided with a locking mechanism 11 that loosely locks the. (2) The locking mechanism 11 has an outer circumferential groove 6b that is deeper than the external teeth 6a provided on the outer circumference of the flange 6, and a clutch member 7.
An inner circumferential groove 7d and an outer circumferential groove 6b provided on the inner surface of the
A synchronous engagement friction clutch according to claim 1, which is constituted by a cut-off ring 12 fitted into the clutch.