JPS6349672B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention biases a sliding operating member for a clutch and a friction brake to a position where the clutch is engaged and the brake is disengaged, and hydraulic adjustment is applied to a hydraulic piston that operates the operating member. Accordingly, a transmission state in which the clutch is engaged and the brake is disengaged, a transmission stop state in which both the clutch and the brake are disengaged, and a braking state in which the clutch is disengaged and the brake is engaged, respectively. The present invention relates to a clutch/brake device configured such that the clutch and brake can be operated with a light operating force sufficient to operate a hydraulic pressure adjustment mechanism.

In the clutch/brake device mentioned above, conventionally,
In order to obtain the hydraulic conditions for obtaining each of the transmission state, transmission stop state, and braking state, a throttle valve is connected to a pressure oil relief path connected to a pressure oil supply path to the hydraulic piston by means of a clutch brake operating tool. By placing the throttle valve in a non-operating position that closes the pressure oil relief passage, the pressure oil condition relative to the piston is brought into a braking state, and the throttle valve is placed in the operating position. By returning a part of the pressure oil supplied from the pump to the tank, the pressure oil state for the piston is made to appear in a state where transmission is stopped, and when the viscosity of the hydraulic oil changes, the operating member The hydraulic pressure that acts to bring the transmission to the stop position changes in magnitude, and the position of the operating member for disengaging the clutch and disengaging the brake changes, which may result in failure of the clutch or brake to disengage. Ta. In order to prevent this, the throttle valve is capable of stepless hydraulic adjustment so that the operating member can be adjusted to an operating position that ensures clutch disengagement and brake disengagement even if the viscosity of the hydraulic oil changes. When configured,
Depending on the viscosity of the hydraulic oil, the position of the operating tool at which the transmission stop state appears will change, and for example, it is necessary to switch from the transmission state to the transmission stop state after some time has elapsed after the start of operation. However, there has been a problem in that the operating tool operating stroke changes depending on the oil temperature, such as the operating tool operating stroke becoming shorter than at the start of operation, resulting in poor operability.

An object of the present invention is to enable reliable clutch disengagement and brake disengagement when the transmission is stopped, regardless of the viscosity of the hydraulic oil, and without the inconvenience of changing the operation stroke of the operating tool. .

Next, embodiments of the present invention will be described based on the drawings.

As shown in FIG. 1, the output of the engine 1 is introduced into a transmission case 3 via a transmission belt 2, and is output from the transmission case 3 to a pair of left and right crawler traveling devices 4a and 4b. This constitutes a traveling transmission device for the combine harvester.

The transmission case 3 includes a transmission 5 and a pair of left and right crawler drive shafts 6 from the transmission 5.
A pair of clutches 7a, 7b that separately disconnect the power transmission to a, 6b and direct the aircraft, and a left and right traveling device 4.
A pair of brakes 8a and 8b are provided internally, respectively, for braking brakes a and 4b separately to steer the aircraft in a small direction.

Each of the clutches 7a and 7b includes:
As shown in FIGS. 2 and 3, an internal gear 9 forming a driving rotating body is provided in the boss portion of the output gear 10 of the transmission 5, and a clutch gear 11 is provided at one end. The clutch gear 11 connects the cylinder 12 as a member to the gear mechanism 13a or 13 on the crawler drive shaft 6a or 6b.
Transmission gear 14a or 14 interlocked via b
The clutch gear 11 is externally attached to the support shaft 16 through the cylinder 15 so as to be relatively rotatable, and the clutch gear 11 connects the cylinder 12 to the transmission gear 1.
The clutch gear 11 is configured to be slid with respect to the support shaft 16 together with the cylindrical body 15 so as to be engaged with and disengaged from the internal gear 9 while being engaged with the internal gear 9, and the position where the clutch gear 11 is engaged with the internal gear 9. When the cylinder body 12 is slid toward the output gear 10 and the clutch gear 11 is engaged with the internal gear 9, the cylinder body 12 is in the engaged state. Output gear 10
Clutch gear 11 by sliding it away from the clutch gear 11.
When it is removed from the internal gear 9, it is in the cut state and is biased in the engaged state.

Each of the brakes 8a and 8b is configured by:
A brake casing 19 to which a plurality of friction ring plates 18 are slidably attached is fixed to the wall of the transmission case 3, and a plurality of covers, one of which is interposed between the friction plates 18, are fixed to the wall of the transmission case 3. The brake ring plate 20 is attached to the end of the cylindrical body 12 opposite to the clutch gear 11 so as to be able to slide and rotate integrally with the cylindrical body 12 to the brake casing 19.
When the friction plate 18 and the brake plate 20 are pressed against the brake casing 19 through the press ring 21 by sliding the brake plate 18 and the brake plate 20 to the side, the brake casing 19 is brought into contact with the brake casing 19 through the cylinder body 12, the transmission gear 14a or 14b, and the gear mechanism 13a or 13b. to apply braking to the crawler drive shaft 6a or 6b, and to slide the cylindrical body 12 toward the output gear 10 side to apply friction to the friction plate 18 and the braked plate 20.
When the pressure on the brake casing 19 is released, the brake is in a cut state and is biased to cut by a spring 17, and is of a wet friction type.

The operating structures for the clutch 7a and brake 8a for the left traveling gear 4a and the clutch 7b and brake 8b for the left traveling gear 4b are constructed as shown in FIG.

That is, a ring-shaped hydraulic piston 22 acts on the clutch side end of the cylinder 12 to perform sliding operation.
is provided between the support shaft 16 and the pressure oil chamber forming cylinder 23 interposed between the support shaft 16 and the output gear 10, and the pressure oil chamber 24 for the piston 22 is provided between the support shaft 16 and the pressure oil chamber forming cylinder 23 interposed between the support shaft 16 and the output gear 10. Oil supply path 2 formed inside
5. Annular oil supply path 2 formed in the transmission case 3
6 and piping 27 forming an external oil supply path to the pump 28, and the transmission case 3
It is configured such that the lubricating oil present therein is supplied as hydraulic oil. An oil passage 2 is formed in the hydraulic piston 22 to supply pressure oil to the hydraulic piston 22.
A discharge port 31 configured to discharge into the mission case 3 through an oil passage 30 formed in the cylinder body 12 and the cylinder body 12 is formed on the outer circumference of the cylinder body 12 so as to move integrally with the cylinder body 12, A ring opening/closing valve 32 for the discharge port 31 is externally attached to the cylindrical body 12 so as to be slidable relative thereto, and a shift fork 34 is attached to the transmission case 3 so as to be swingable via a support shaft 33, and a release. The foot-swinging pedal 36a or 36b is linked via the wire 35, and a relief valve 37 is connected to the piping 27, so that when the pedal 36a or 36b is in the non-depressing position A, the clutch 7a or 7b is engaged. When the brake 8a or 8b is in a transmission state in which it is disengaged and the pedal 36a or 36b is moved to the first depressed position B, the clutch 7a or 7b and the brake 8a or 8b are both in a transmission stop state in which they are disengaged. 36b is moved to the second depressed position C, which is further depressed from the first depressed position B, the clutch 7
A or 7b is turned off and the brake 8a or 8b is turned on, resulting in a braking state.

That is, when the pedal 36a or 36b is in the non-depressed position A, as shown in FIG. 3 by the clutch 7b and brake 8b for the right traveling gear 4b,
The on-off valve 32 is in the fully open position, and the hydraulic piston 22
Pressure oil supplied to the pressurized oil chamber 24 is discharged from the discharge port 31, and the oil pressure in the pressure oil chamber 24 is adjusted to a pressure value that allows the cylinder body 12 to be operated and maintained by the spring 17 in the position where the transmission state is manifested. It will become. Then, when the pedal 36a or 36b is operated to the first depression position B, as shown in FIG.
2 is in a position closer to the brake 8a or 8b than the fully open position, and at this time, the cylinder body 12 is in the transmission state position, so that the exhaust port 3
1 is fully closed and the cylindrical body 12 compresses the spring 17 with the supplied pressure oil while applying the brake 8a or 8b.
With this sliding, the discharge port 31
A part of the pressure oil comes out from the on-off valve 32 to the brake 8a or 8b side, and the on-off valve 32 enters the throttle open state, and a part of the pressure oil supplied to the piston 22 begins to be discharged, resulting in the transmission stopped state. However, the oil pressure in the pressure oil chamber 24 reaches a pressure value that maintains the cylindrical body 12 in balance with the biasing force of the spring 17 in the middle of the sliding range. Then, when the pedal 36a or 36b is operated to the second depression position C, the clutch 7a and brake 8 for the left traveling device 4a are activated as shown in FIG.
As shown in a, the on-off valve 32 is in a position closer to the brake 8a or 8b than the throttle opening position, and at this time the discharge port 31 is fully closed and the cylindrical body 12 is closed by the supplied pressure oil. While further compressing the spring 17, it is slid toward the brake 8a or 8b, and despite this sliding, the on-off valve 32 is in a state of fully closing the discharge port 31, and the cylinder 12 is slid to the end of its stroke. As the oil pressure in the rear pressure oil chamber 24 reaches a predetermined value, a portion of the pressure oil supplied from the pump 28 is returned to the mission case 3 through the relief valve 37. That is, the cylindrical body 12
The spring 17 is placed in a position where the braking state is achieved.
The relief pressure of the relief valve 37 is set to a pressure value maintained against the
The hydraulic pressure is maintained.

FIG. 5 shows another embodiment of the configuration of the discharge port 31 and the on-off valve 32. The discharge port 31 is formed to open in the axial direction of the cylinder 12, and the on-off valve 32 is It is configured to open and close from the side, and to change between a fully open state and a throttle open state depending on the degree of approach to the discharge port forming portion.

In the above implementation configuration, the hydraulic pump 28 is
Although the hydraulic oil is separately supplied to the pair of hydraulic pistons, a dividing valve may be provided so that one pump supplies the hydraulic oil to the pair of hydraulic pistons separately.

The pedals 36a, 36b can be changed to manual levers, and these are collectively referred to as clutch brake operating tools 36a, 36b.

The present invention can also be applied to clutch/brake devices that act on various devices other than traveling devices.

In summary, the characteristic configuration of the present invention is that in the above-described clutch/brake device, a discharge port 31 for supplying pressure oil to the hydraulic piston 22 is provided.
are formed on each of the sliding operation member 12 and the hydraulic piston 22 that moves integrally therewith, and the on-off valve 32 for the discharge port 31 is linked to the clutch/brake operation tool 36a or 36b. The discharge port 31 is mounted so as to be slidable relative to the sliding operation member 12 and to be freely changeable in position in three positions: a fully open position, a fully closed position, and an intermediate throttle open position of the discharge port 31; At the throttle opening position, the pressing force of the hydraulic piston 22 under throttle resistance and the biasing force of the biasing means 17 are balanced, and the clutches 7a, 7b are disengaged when the brakes 8a, 8b are disengaged. It is configured to be operated, and its functions and effects are as follows.

That is, as described in detail in the embodiment section, the on-off valve 32 is moved and adjusted, and the operating member 1 is
2 and adjust the discharge port 31, which moves integrally with the operating member 12, to the throttle open state, and adjust the hydraulic pressure so that the transmission is stopped, even if the viscosity of the hydraulic oil changes. , and by simply positioning the on-off valve 32 at one predetermined transmission stop position, the discharge port 3 is opened by the hydraulic pressure acting on the piston 22 and the force for returning the operating member.
The opening amount of clutch 7a or 7 is automatically adjusted.
The operating member 12 will be adjusted and maintained at a preset transmission stop position that ensures that both the brake and the brake 8a or 8b are turned off. Therefore, regardless of the viscosity of the hydraulic oil, the clutch 7a or 7
Both brakes 8a and 8b can be operated reliably to disengage, and safe driving can be performed without the transmission not being disconnected or the brakes being unexpectedly applied even though they are operated. In addition, the stroke required for operating the operating tool can be made constant, making it possible to improve the operability such that erroneous operation is less likely to occur.

[Brief explanation of drawings]

The drawings show an embodiment of the clutch/brake device according to the present invention, in which Fig. 1 is a schematic side view of a combine harvester, Fig. 2 is a partially cutaway front view of a transmission case, and Fig. 3 is a cross-section of the clutch/brake. Figure, 4th
The figure is a cross-sectional view showing a state in which the transmission of the clutch/brake is stopped, and FIG. 5 is a cross-sectional view showing another embodiment of the exhaust port and the opening/closing valve. 7a, 7b...clutch, 8a, 8b...brake, 9...driving side rotating body, 12...operating member, 16...
Support shaft, 17...Biasing means, 22...Hydraulic piston, 3
1...Discharge port, 32...Opening/closing valve, 36a, 36b
...Manipulation tools.

Claims (1)

[Claims] 1 A hydraulic piston 22 is mounted on the driving side rotary body 9 and is slidably movable along its rotational axis direction, and a sliding operation member 1 is attached to the clutch 7a or 7b and the friction type brake 8a or 8b.
2 is provided slidably along the pressing direction by the hydraulic piston 22, and this sliding operation member 1
biasing means 1 for biasing 2 in a direction opposite to the pressing direction;
7 is provided, and the clutches 7a and 7b are disengaged by releasing the interlock with the driving side rotating body 9 as the hydraulic piston 22 presses, and a brake 8 is applied by braking the sliding operation member 12 whose interlock is released.
The clutch/brake device is configured such that the clutches 7a, 7b are engaged and the brakes 8a, 8b are disengaged as the urging means 17 is operated. A discharge port 31 for supplying pressure oil to the hydraulic piston 22 is connected to the sliding operation member 12,
The sliding operation member 12 is formed on each of the hydraulic pistons 22 that move integrally with the hydraulic piston 22, and an on-off valve 32 for the discharge port 31 is linked to the clutch/brake operation tool 36a or 36b.
The discharge port 31 is mounted so as to be slidable relative to the exhaust port 31, and to be repositionable in three positions: a fully open position, a fully closed position, and an intermediate open throttle position. The pressing force of the hydraulic piston 22 and the urging force of the urging means 17 are balanced, and when the brakes 8a, 8b are in the disengaged state, the clutches 7a, 7
A clutch/brake device in which b is operated in a disengaged manner.