JPS6242585Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention can be used in various work vehicles, such as a combine harvester in which a reaping part is provided so that it can be raised and lowered by a drive, and a riding tiller that is equipped with a rotary tiller that can be raised and lowered by a drive. A transmission case is provided on a traveling aircraft to which a drive-type ground work device is attached so as to be able to move up and down, and a transmission hydraulic cylinder for transmission is attached to a transmission shaft for transmission mounted on the transmission case, and a hydraulic cylinder for transmission is attached to the transmission shaft for transmission, and pressure oil from a hydraulic pump is supplied. The present invention relates to a hydraulic power transmission for a working vehicle configured to supply power to the hydraulic cylinder via a control valve.

In the above work vehicle, when changing the direction of the vehicle on a headland, it is necessary to raise the work device and stop driving the work device, but in addition to these operations, a steering operation is also required to change the direction of the vehicle. This makes the operation complicated and it is possible to forget to stop the drive of the working device.

In addition, in this type of work vehicle, the gear shift operation can be performed extremely easily and quickly using a control valve, so it is possible to quickly shift to the neutral position during forward work, or to quickly shift gears from the forward position to the reverse position. Sometimes I end up going. If you suddenly switch from forward to neutral, the traveling load and the hydraulic pump load will suddenly decrease, and the engine may momentarily stop rotating due to the sudden change in load. If the switching is too rapid, a shock may occur due to a sudden change in the direction of travel of the vehicle.

The present invention was developed by focusing on the above-mentioned phenomenon, and aims to facilitate operations such as when turning the vehicle on a headland, as well as alleviate problems caused by rapid gear shifting operations. The purpose is to provide an effective means to do so.

In order to achieve the above object, the present invention provides the above-mentioned hydraulic power transmission for a working vehicle, which includes a hydraulic actuator for stopping the driving of the working device, and a hydraulic actuator that stops the driving of the working device. An oil path to the hydraulic actuator is connected to the control valve so that when at least one of It is characterized by being connected in communication.

According to the above configuration, for example, if the hydraulic actuator is set to operate at the neutral position of the hydraulic control valve, trouble may occur in the working device part during forward travel, and the vehicle body may need to be stopped suddenly. When the hydraulic control valve is switched to the neutral position, the vehicle body stops and the drive of the working device is cut off by the operation of the hydraulic actuator. In this case, the traveling load suddenly decreases and the load on the transmission hydraulic system is reduced, but the hydraulic system load on the hydraulic actuator for stopping the drive of the work equipment is newly added, so the engine driving the hydraulic pump is Sudden decrease in load will be suppressed.

In addition, if the hydraulic actuator is set to operate when the hydraulic control valve is in the reverse position, when changing the direction of the vehicle by a switch turn on a headland, the hydraulic control valve can be quickly moved from the forward position to the reverse position. When the hydraulic actuator is activated, the drive of the work equipment is cut off and the work equipment moves backward, but pressure oil is simultaneously supplied to the hydraulic cylinder for reverse gear change and the hydraulic actuator for stopping the work equipment drive. Therefore, there is a time delay in supplying pressure oil to the hydraulic cylinder for reverse gear change, and the shock associated with switching from forward to reverse is alleviated.

It goes without saying that if the hydraulic actuator for stopping the working device is operated at the neutral position and the reverse position of the hydraulic control valve, both of the above operations will be performed.

The present invention works as described above,
The following effects can be expected.

In other words, according to the present invention, when the hydraulic control valve is switched to the neutral or reverse position to change the direction of the vehicle body, the drive of the working device is stopped by supplying pressure oil to the hydraulic actuator. In particular, it eliminates the need for special operations to stop working equipment when changing vehicle direction, etc.
This not only improves operability, but also makes it easy to use it effectively for things such as suppressing malfunctions in engine rotation due to a sudden load reduction when the vehicle is stopped, and mitigating shock when rapidly switching from forward to reverse. .

Hereinafter, embodiments of the present invention will be described in detail with reference to illustrative drawings.

A reaping unit 2 raises and reaps planted stem culms in the field, transports the cut stem culms to the rear of the machine, changes its posture to a sideways posture, and transfers them to the feed chain 1, and feeds the cut stem culms. A threshing device 3 that performs threshing while being held and transported by a chain 1 is connected to a traveling vehicle body equipped with a crawler traveling device 4 and a control section 5, and the reaping section 2 is connected to a hydraulic cylinder 2a.
It is installed so that it can be driven up and down via the drive, forming a combine harvester.

To drive the traveling device 4, the power from the engine 6 is transferred to a gear-type transmission mechanism 7 that can freely change three speeds for the auxiliary transmission, and a hydraulic type that can freely change the speeds to three forward speeds and one reverse speed for the main speed change. power transmission 8
As a whole, the transmission is configured to be able to freely change gears to nine forward speeds and three reverse speeds, and will be described in detail below.

That is, the engine 6 is placed in the transmission case 9.
an input shaft 10 interlocked with the driving gear, first to third transmission shafts 11, 12, 13 for traveling speed change, a steering clutch 14,
14, a left and right running drive shaft 16, 16, a fourth transmission shaft 17 for transmitting power to the reaping section 2 and the threshing device 3, and an output shaft 18, respectively, are mounted on a shaft, and the input shaft 10 and The gear-type auxiliary transmission mechanism 7 is provided between the first transmission shaft 11 and the gear-type transmission mechanism 19, which is capable of shifting in three stages, is provided between the fourth transmission shaft 17 and the output shaft 18. Said second transmission shaft 1
2, first and second hydraulic clutches 20, 2 for gear shifting;
1, and third and fourth hydraulic clutches 22 and 23 are attached to the third power transmission shaft 13, respectively, and are coupled to be integrally rotatable by engaging the clutches 20, 21, 22, and 23, respectively. Transmission gear 2
4... are loosely fitted into the second and third transmission shafts 12, 13, respectively, and the first
or fourth hydraulic clutch 20, 21, 22, 23
Each cylinder 20a, 21a, 22a, 23a
It is configured to supply pressure oil to.

The hydraulic cylinders 20a, 21a, 22a, 2
The hydraulic circuit for 3a is configured to supply gear oil in the transmission case 9 via an oil filter 25, a hydraulic pump 26, and a rotary control valve 27, as shown in FIG. By switching the control valve 27, a neutral state N, a reverse state R, and forward first to third speed states F ₁ , F ₂ , and F ₃ can be selectively obtained. An accumulator 28 is connected in communication with the pressure oil supply path to the control valve 27, and is configured to prevent sudden start when switching from a neutral state to a first forward speed state or a reverse state. . Further, a return oil passage 30 having a relief valve 29 interposed therein is connected in the middle of the pressure oil supply passage to the control valve 27, and the return oil passage 30 is supplied to the hydraulic clutches 20, 21, 22, and 23. The hydraulic clutch 20 is configured as shown in FIG.
21, 22, and 23 are each cooled.

Although not shown, the control valve 27 and the accumulator 28 are provided in the transmission case 9 with their longitudinal directions parallel to the transmission shaft 11 and with their end surfaces abutted against each other, and an oil filter 25 is also provided with its longitudinal direction parallel to the transmission shaft 11...
and the oil filter 25 and the hydraulic pump 2.
6, control valve 27, accumulator 2
8, and cylinders 20a, 21a, 22a, 2
The in-shaft oil passages communicating with each of the transmission case 3a are connected through oil passages formed on the mating surfaces of the transmission case 9 and the hydraulic plate attached thereto.

A simple hydraulic actuator as an example of a hydraulic actuator that can be operated by bringing the tension clutch arm 32 close to the belt type transmission mechanism 31 from the output shaft 18 to the bevel case 2a for driving the reaping part 2 and moving it in contact and pressing. A dynamic hydraulic cylinder 33 is provided, and an oil passage 34 to the hydraulic cylinder 33 is connected to the transmission control valve 27, and control is performed only when the control valve 27 is in the neutral position and reverse operation position. The oil passage 34 is connected to the hydraulic pump 26 via the valve 27.
The reaping section 2 is configured to be connected in communication with the reaping section 2, and the drive of the reaping section 2 is automatically stopped both when the vehicle is stopped and when traveling backwards while supplying pressure oil to the cylinder 23a.

To configure the power transmission 8, for example, a transmission gear 24 is loosely fitted to the transmission shafts 12, 13, and a connecting pin is provided in the transmission shafts 12, 13 for connecting or disconnecting the transmission gear 24. It may be provided so as to be movable in the radial direction, and may be provided with a cylinder for operating the connecting pin to move in and out.

The present invention is not limited to the above-mentioned combine harvester.
For example, the present invention can be applied to hydraulic power transmissions for various types of work vehicles, such as ride-on cultivators in which a rotary tiller is mounted on a traveling machine so as to be movable up and down, and various work vehicles in which various ground work devices 2 are mounted in a movable manner.

[Brief explanation of the drawing]

The drawings show an embodiment of the hydraulic power transmission for a working vehicle according to the present invention, with Fig. 1 being an overall side view, Fig. 2 being a schematic vertical sectional view of the transmission case, and Fig. 3 being a hydraulic circuit diagram. be. 2...Drive type ground work device, 9...Mission case, 12, 13...Transmission transmission shaft, 20a,
23a... Hydraulic cylinder for gear change, 26... Hydraulic pump, 27... Control valve, 33... Hydraulic actuator, 34... Oil passage.

Claims (1)

[Scope of utility model registration request] A transmission case 9 is provided on a traveling machine to which a drive-type ground work device 2 is attached so as to be able to move up and down, and a transmission shaft 12 for speed change is mounted on the transmission case 9.
Hydraulic power transformer for a working vehicle, in which hydraulic cylinders 20a...23a for shifting are attached to the hydraulic cylinders 20a...23a, and pressure oil from a hydraulic pump 26 is supplied to the hydraulic cylinders 20a...23a via a control valve 27. The transmission is provided with a hydraulic actuator 33 for stopping the driving of the working device 2, and when the control valve 27 is operated to at least one of the neutral position and the reverse position, Pressure oil is connected to the hydraulic actuator 3.
A hydraulic power transmission for working, in which an oil passage 34 to the hydraulic actuator 33 is connected to the control valve 27 so that the hydraulic actuator 33 is supplied to the control valve 27 and the driving of the working device 2 is stopped.