JPH0672624B2 - Hydraulic clutch device for vehicle running - Google Patents

Description

The present invention relates to a vehicle hydraulic clutch device and is used for a tractor and the like.

(Prior Art) A first hydraulic clutch and a second hydraulic clutch for traveling are arranged side by side in the axial direction in a common driving plate so that pistons of the respective hydraulic clutches operate in mutually opposite directions. With
Both pistons of the hydraulic clutch are linked and linked in the axial direction,
A technique in which one hydraulic clutch is provided with an elastic body for urging a piston so that the one hydraulic clutch is in a connected state when the hydraulic pressure is released is known from Japanese Patent Publication No. 60-2538.

This technique has advantages that the engine can be started and pulled even when the engine cannot be started and the hydraulic pump does not operate, and the engine can be braked when the engine is stopped.

(Problems to be Solved by the Invention) However, in the above-mentioned prior art, the pressure receiving areas (operating hydraulic pressure areas) of the pistons are made equal to each other, and the urging force of the elastic body acts on one of the pistons. Therefore, the piston having the elastic body receives both the hydraulic pressure and the urging force of the elastic body, while the piston not having the elastic body receives only the hydraulic pressure, where the shafts of both pistons are The forces acting in the axial direction were different from each other, which led to a shift in the clutch connection.

An object of the present invention is to provide an accurate torque transmission by providing an elastic body and making it possible to perform engine braking and the like, by making the acting force of both pistons the same, making the clutch disengagement and connection the same. And

(Means for Solving the Problems) In the present invention, the first hydraulic clutch 7 and the second hydraulic clutch 9 for traveling are arranged side by side in the axial direction in the common drive plate 5, and each hydraulic clutch 7, The pistons 11 and 12 of 9 are operated in mutually opposite directions, and the pistons 11 and 12 of the hydraulic clutches 7 and 9 are interlockingly coupled in the axial direction to release the hydraulic pressure to one hydraulic clutch 9. Sometimes, the one hydraulic clutch 9
The elastic body 30 that urges the piston 12 so that the
In order to achieve the stated purpose,
The following technical measures are taken.

That is, the present invention is characterized in that both pistons 11 and 12 have a large working hydraulic pressure area on one side and the other is small on the other side, and the elastic body 30 is provided on the piston 12 on the smaller area side. is there.

(Operation) The hydraulic pressure from a hydraulic pump (not shown) is sent to the cylinder chambers 8 and 10 of the pistons 11 and 12 via a control valve (not shown) and pressed in the axial direction of the pistons 11 and 12. Clutch plate 1
6 and 24 are pressed together to transmit torque.

In this case, when the hydraulic pressure acts on the cylinder chamber 8 of the piston 11 having the larger pressure receiving area, the piston 11 is pushed against the urging force of the elastic body 30, and conversely, the piston having the smaller pressure receiving area is provided. When the hydraulic pressure acts on the cylinder chambers 10 of 12, the urging force of the elastic body 30 is applied to push the piston 12.

Here, the hydraulic pressure due to the area difference between the pistons 11 and 12 is corrected by the biasing force of the elastic body 30, so that
The pressing force of 2 is constant, the pressure contact between the clutch plates 11 and 24 is made uniform, and the torque is transmitted with a constant mutual force.

When the hydraulic pump fails, the elastic force of the elastic body 30 pushes the piston 12 on the side with the smaller area to move the clutch plate 24.
It is possible to press, and tow and start it here.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a clutch housing or a transmission case which is a vehicle body of a tractor, and a traveling hydraulic clutch device 2 is built in this internal space.

3 is a propulsion shaft for traveling, 4 is a propulsion shaft for PTO, both of which are interlocked with an engine (not shown), and the traveling shaft has a hollow shaft structure.
The one for O is inserted in the one for traveling.

Reference numeral 5 is a driving plate (clutch body), which is a propulsion shaft 3 for traveling.
It is attached by a key 6 on the upper side, and a cylinder chamber 8 for the first hydraulic clutch 7 and a cylinder chamber 10 for the second hydraulic clutch 9 are formed on the driving plate 5 side by side in the axial direction. Has been done.

Pistons 11 and 12 are fitted in the cylinder chambers 8 and 10, respectively.One of the pistons 11 and 12 has a large area of working hydraulic pressure and the other has a small area, and the screw bolt 13
And the pistons 11 and 12 are interlockingly connected in the axial direction via a seal collar 14 and the like.

Reference numeral 15 is a driven plate for the first hydraulic clutch 7, which has a clutch plate 16, which is a piston 11 and a pressure receiving plate.
Further, the driven plate 15 is interposed between the driven plate 15 and the driving shaft 3, and the driven plate 15 is supported on the propulsion shaft 3 via a needle bearing 18 and has a gear 19.

Reference numeral 20 denotes a driven plate for the second hydraulic clutch 9, which is supported on the propulsion shaft 3 via roller bearings 21 and is connected to the output shaft 22 by splines or the like.

The driven plate 20 has a clutch plate 24 interposed between the piston 12 and the pressure receiving plate 23, and the driven plate 20 has a gear 25.

Reference numeral 26 denotes a counter shaft, which has a gear 28 that meshes with the gear 19 via the idle gear 27 and a gear 29 that directly meshes with the gear 25. Here, the traveling hydraulic clutch device 2 is for forward / reverse switching. ing. However, the clutch device 2 may be for switching between high and low.

Reference numeral 30 denotes an elastic body, which brings the piston 12 into a connected state when the hydraulic pressure is released, that is, when the hydraulic pump (not shown) does not operate because the engine is stopped or when the hydraulic pressure does not occur due to a control valve failure or the like. The piston 12 having a small pressure receiving area, that is, the cylinder chamber 10 side,
Circumferential multiple locations (for example, 4
6 springs, 8 springs, etc.).

Since the elastic force and the urging force of the elastic body 30 are different between the pressing force (oil pressure) against the large area piston 11 and the pressing force (oil pressure) against the small area piston 12, the clutch plate 16 The urging force is determined in consideration of making the pressure contact forces of 24 and 24 different evenly, that is, in order to make the pressing force substantially equal.

In the drawing, the hydraulic clutch on the forward rotation side is provided with the elastic body 30, but this may be on the reverse rotation side, and when the traveling hydraulic clutch device 2 is for high / low switching, it is on the high side. The elastic body 30 may be provided on either one of the low side and the low side, but it is desirable to provide the elastic body 30 on the low side when starting traction.

Reference numeral 31 is an oil passage for operating hydraulic pressure, and each is a cylinder chamber.
8 and 10 are communicated with each other via passages 31A and 31B, and the hydraulic pressure from the internal and external hydraulic pumps is sent via a control valve.

Reference numeral 32 denotes an oil passage for lubrication, which lubricates each bearing and cools each clutch plate 16 and 24, especially in the half-clutch state or the disengaged state.

33 and 34 are piston return springs, which are elastic bodies 3
Since 0 is provided, it can be omitted.

FIG. 2 shows another embodiment in which the pistons 11 and 12 are interlockingly connected. Of the screw bolts 13 and collars 14 provided at four places in the circumferential direction, the outer peripheral shape of the collar 14 is as shown in the figure. By adopting a shape, both pistons 11 and 12 can be smoothly operated in the axial direction even if there is a manufacturing error in the pistons 11 and 12 or the cylinder chambers 8 and 10.

According to the above-described embodiment, when the hydraulic pressure from the hydraulic pump is sent to the cylinder chamber 8, the piston 11 operates against the elastic force of the elastic body 30 and presses the clutch plate 16, In the figure, the torque of the propulsion shaft 3 is transmitted to the output shaft 22 as a torque in the reverse rotation direction via the counter shaft 26 and the like. When the idle gear 27 is removed and the gears 19 and 28 are engaged, the decelerated torque is transmitted to the output shaft 22 via the gears 25 and 29.

On the other hand, when the hydraulic pressure is delivered to the cylinder chamber 10, the piston 12 having a small area is driven by the hydraulic pressure and the urging force of the elastic body 30.
Is actuated, and the clutch plate 24 is pressed into contact, whereby the torque of the propulsion shaft 3 is directly transmitted to the output shaft 22.

Further, when the hydraulic pump does not operate due to an engine failure or the like, the hydraulic pressure in each cylinder chamber 8 is released, and at this time, the elastic force of the elastic body 30 causes the clutch plate 24 to press-contact in this example. To be done.

Therefore, the engine can be started by towing or the like, and the engine brake can be applied when the engine is stopped while climbing the slope.

(Effects of the Invention) The present invention is as described above, and a first hydraulic clutch for traveling and a second hydraulic clutch for traveling are arranged side by side in the axial direction in a common driving plate, and the pistons of the respective hydraulic clutches are mutually connected. And the pistons of the two hydraulic clutches are interlocked in the axial direction, and the pistons are connected to one of the hydraulic clutches so that when the hydraulic pressure is released, the one hydraulic clutch is connected. Since an elastic body that urges the vehicle is provided, even if there is an engine stop during climbing, the engine brake can be applied to ensure safety, and towing start can be achieved. it can.

Moreover, the present invention is characterized in that both pistons have a large working hydraulic pressure area on one side and the other is small, and the elastic body is provided on the piston on the side having a smaller area. In addition to the basic operation effect, even if the elastic body is provided, there is an advantage that the pressure contact force between the first hydraulic clutch and the second hydraulic clutch can be made uniform, and the operation can be performed smoothly and surely.

[Brief description of drawings]

The drawings show an embodiment of the present invention, FIG. 1 is an elevational sectional view, and FIG. 2 is a sectional view of a second embodiment showing only essential parts. 5 ... prime mover, 7 ... first hydraulic clutch, 9 ... second hydraulic clutch, 8,10 ... cylinder chamber, 11, 12 ... piston, 13 ... screw bolt, 30 ... elastic body.

Claims (1)

[Claims] 1. A first driving hydraulic clutch 7 and a second driving hydraulic clutch 9 are arranged side by side in the axial direction in a common driving plate 5.
The pistons 11 and 12 of the respective hydraulic clutches 7 and 9 are operated in mutually opposite directions, and the pistons 11 and 12 of the hydraulic clutches 7 and 9 are interlockingly coupled in the axial direction so that one hydraulic clutch 9 is connected. , An elastic body for urging the piston 12 so that the one hydraulic clutch 9 is brought into a connected state when the hydraulic pressure is released.
In the one provided with 30, the pistons 11 and 12 have a large working hydraulic pressure area on one side and the other is small, and the piston 12 on the side with a smaller area
A hydraulic clutch device for traveling of a vehicle, characterized in that an elastic body (30) is provided on the.