JPH044500Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is based on a hydraulic system that connects a lifting hydraulic cylinder that drives the reaping pretreatment section up and down with respect to this machine and a switching valve that operates this lifting hydraulic cylinder. The present invention relates to an elevating device for a reaping pre-processing section of a reaping harvester, which has an accumulator connected to a midway point of the circuit.

[Conventional technology]

Conventionally, in this type of pre-harvesting unit lifting device, for grain culms that are less prone to lodging, the pre-harvesting unit is raised to an appropriate height without colliding with the ground, allowing efficient reaping and harvesting work. The pre-harvest treatment section is set as low as possible relative to the ground for grain culms that have fallen down and is harvested efficiently.In order to perform so-called floating work, the pre-harvest treatment section is floated using the accumulated pressure of the accumulator. It is constructed so that it can be supported.

[Problem that the invention attempts to solve]

According to the above-mentioned conventional technology, since the pressure inside the accumulator is usually lower than the pressure required to raise the pre-reaping treatment section, when raising the pre-reaping treatment section in the floating state to an appropriate height, The pressure inside the accumulator must be increased to the pressure required to raise the pre-harvest treatment section, and it takes time from the start of the raising operation until the pre-harvest treatment section actually rises, resulting in poor responsiveness. It was bad.

In order to solve this problem, for example, as shown in FIG. 3, an accumulator 13a for high pressure and a low pressure The high-pressure accumulator 13a absorbs the shock when the reaping pretreatment section contacts the ground, etc., and the low-pressure accumulator 13b is equipped with a variable throttle valve 20 to prevent floating. The variable throttle valve 20 is configured so that the work can be performed with high accuracy, and when the floating work is not performed, that is, when the work is performed with the reaping pretreatment section raised to an appropriate height.
The reaping pre-processing section is raised in a state with good responsiveness without increasing the pressure in the low-pressure accumulator 13b used for floating work by blocking the communication with the low-pressure accumulator 13b. However, in this case, two accumulators are required, leading to an increase in cost and a disadvantage in terms of space.

The present invention aims to solve the above-mentioned problems of the prior art with a simple structure using a relatively inexpensive and small valve.

[Means for solving problems]

The characteristic configuration of the present invention for achieving the above object is that in the reaping pre-processing section elevating device of the reaping harvester described above, the hydraulic circuit and the accumulator are connected between the hydraulic circuit and the accumulator. An open/close valve that can be freely switched between a communication state and a cutoff state and a check valve that allows pressure oil to be supplied from the accumulator to the hydraulic circuit are connected in parallel, and the secondary side of the relief valve connected to the hydraulic circuit is connected in parallel. The port is connected to the accumulator, and this configuration provides the following effects.

[Effect]

During floating work, the on-off valve is switched to the communicating state to perform highly accurate floating work using the accumulator, and when no floating work is to be performed, the on-off valve is switched to the off state and the reaping pre-treatment section is set to an appropriate height. It is not necessary to increase the pressure inside the accumulator when raising the system, and when the pre-reaping treatment section comes into contact with the ground etc. and the pressure inside the hydraulic circuit increases,
Pressure oil is released into the accumulator through the pressure control valve to reduce the impact on the reaping pretreatment section.
As the contact between the reaping pretreatment section and the ground is released, pressure oil flows back from the accumulator to the hydraulic circuit via the check valve, and the relative posture of the reaping pretreatment section with respect to the machine returns to its original position. let

[Effects of the invention] Although it has a simple structure using one accumulator and inexpensive and small valves such as an on-off valve, a check valve, and a pressure control valve, the accumulator can provide shock mitigation function even when not performing floating work. It has now become possible to improve the responsiveness to the raising operation of the reaping pretreatment section using the switching valve without impairing the operation.

〔Example〕

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

As shown in FIG. 4, a reel 3 for raking the planted grain culms toward the rear of the machine, and a reaping device 4 for reaping the raked grain culms are attached to the front part of the machine frame 2 equipped with the crawler traveling device 1. , an auger 5 that receives the reaped grain culm, collects it in the center of the width of the machine and sends it out to the rear, and a conveyor 6 that conveys the reaped grain culm to the rear of the machine with the ear tip in front. In addition to being provided with a drive that can be freely raised and lowered, a device 7 for threshing the harvested grain culms supplied from the pre-harvesting processing section A and a tank 8 for recovering the grains after the threshing process are provided on the upper part of the body frame 2. This is a full-culm input type combine harvester, which is an example of a reaping harvester.

As shown in FIG. 1, the drive elevating mechanism of the reaping pre-processing section A comprises a lifting hydraulic cylinder 10 interposed between the support frame 9 of the reaping pre-processing section A and the machine frame 2; This hydraulic cylinder 10
A spring-loaded accumulator 13 is connected to a middle part of the hydraulic circuit 12 that connects the neutral return type three-position switching valve 11 that operates the switching valve 11 with an L-shaped link 14 and a rod 15.
When the manual lever 16 is swung to the raised position U, the switching valve 11 is linked to the manual lever 16 via the
When the reaping pre-processing section A moves up and swings to the neutral position N, the ascending and descending of the reaping pre-processing section A stops and is held at that position. It is configured so that when it swings, it switches to a lowered state and the reaping pre-processing section A descends.

Between the accumulator 13 and the hydraulic circuit 12, a variable throttle valve 17 as an on-off valve, a check valve 18, and a relief valve 19 are connected in parallel. Pressure oil can be supplied to the accumulator 13 through both the variable throttle valve 17 and the relief valve 19, and the variable throttle valve 17 is configured to be shut off when floating work is not performed.

[Another example]

FIG. 2 shows another embodiment of the present invention, in which an oil passage 19a on the primary side of the relief valve 19 and an oil passage 1 on the secondary side
9b, a valve 17 is interposed as an opening/closing valve that can be selectively switched between a state in which the accumulator 13 and the hydraulic circuit 12 are communicated, and a state in which the relief valve 19 and the hydraulic circuit 12 are communicated. Therefore, during floating work, pressure oil is not supplied from the hydraulic circuit 12 to the accumulator 13 via the relief valve 19.

In this embodiment, the valve 17 may be operated in conjunction with the switching valve 11.

The accumulator in the present invention may be a weight type accumulator or an air/gas operated type accumulator.

In addition, when the reaping and harvesting machine is used in a state in which the pre-reaping treatment section is maintained close to the ground and in a state in which it is used in a state where it is further away from the ground than in the above-mentioned state, when driving on the road in the latter state, it is difficult to handle the unevenness of the road surface. Therefore, even if the pre-reaping treatment section is subjected to a large impact in the vertical direction, this device can gently absorb the shock, which has the advantage of avoiding excessive loads being applied to the pre-reaping treatment section. In this case, a loose chain may be used to connect the fuselage from the fixed part to prevent it from descending below a certain height.

Further, this invention is useful when constructing a self-removal type reaping harvester with a simple structure.

[Brief explanation of drawings]

The drawings show an embodiment of the elevating device for the reaping pre-processing section of the reaping harvester according to the present invention, FIG. 1 is a system diagram of the elevating device, FIG. 2 is a system diagram of the elevating device showing another embodiment, and FIG. 3 is a system diagram of the elevating device. 4 is a system diagram of a conventional lifting device, and FIG. 4 is an overall side view of a reaping and harvesting machine. A... Reaping pre-processing section, 10... Lifting hydraulic cylinder, 11... Switching valve, 12... Hydraulic circuit,
13... Accumulator, 17... Opening/closing valve,
18...Check valve, 19...Relief valve.

Claims (1)

[Scope of utility model registration request] For reaping, an accumulator 13 is connected to a midway point of a hydraulic circuit 12 that connects a lifting hydraulic cylinder 10 that drives the reaping pretreatment section A up and down with respect to this machine and a switching valve 11 that operates this lifting hydraulic cylinder 10. In the pre-reaping processing section elevating device of a harvester, the hydraulic circuit 12 and the accumulator 1
3, an on-off valve 17 that can freely switch between communicating and disconnecting the hydraulic circuit 12 and the accumulator 13, and a check valve 18 that allows pressure oil to be supplied from the accumulator 13 to the hydraulic circuit 12. are connected in parallel, and a secondary side port of a relief valve 19 connected to the hydraulic circuit 12 is connected to the accumulator 13.