JPH0246250Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a device for vertically moving agricultural machinery. When a working machine is attached to a vehicle body via an elevating link or the like, the working machine is moved up and down so that the working machine is always controlled at an appropriate height so that work can be performed accurately.
However, with this hydraulic control, when the engine speed is increased using the throttle lever, the hydraulic pump rotates too fast and the work equipment is raised rapidly, causing the work equipment to hunt up and down. This resulted in the machine being propelled while standing up, which had the disadvantage of not being able to run stably and making it impossible to work accurately.

This invention has taken the following technical measures for the purpose of solving the above-mentioned drawbacks.

That is, in this invention, the switching valve 18 of the hydraulic system is switched and the hydraulic cylinder system 7 is activated to move the running wheels 15 up and down, or the working device 8 is moved up and down by the vertical movement of the soil leveling float 12 sliding on the soil surface. In an agricultural working machine that operates to control the working machine part at a substantially constant height with respect to the soil surface, a throttle lever 25 that changes the output of an engine 5 that drives a hydraulic pump 6 of the hydraulic system; pump 6
A throttle valve 24 provided in the flow path through which the oil from the engine is sent to the hydraulic cylinder device 7 is interlocked with the flow path so that the flow path is narrowed when the engine 5 rotates at high speed. Because of the structure of the device, even when the engine rotation is adjusted to high speed, the working machine part does not vibrate vertically and runs stably, allowing accurate work to be carried out.

For example, if this idea is applied to a rice transplanter, the seedling planting depth will be constant and the performance will be improved.

To explain in detail the walking type rice transplanter which is an embodiment of this invention, 1 is a vehicle body, the base is fixed to the rear part of the transmission case 2 at the front and rear intermediate part, and the transmission case for planting seedlings is attached to the rear side. 3 is attached, an engine stand 4 is attached to the front part of the transmission case 2, and an engine 5 is mounted on it.

Reference numeral 6 denotes a hydraulic pump, the case body of which is integrally attached to the upper part of the transmission case 2. This pump 6 is belt-transmitted by the output pulley of the engine 5. Reference numeral 7 denotes a hydraulic cylinder device, and the base side of the cylinder 7a is fixed to the case of the hydraulic pump 6, and a piston 7b is provided so as to protrude rearward.

Reference numeral 8 denotes a working machine, which is a rice transplanting device in the illustrated example, with seedling planting rods 9 on both left and right sides of the lower side of the seedling planting transmission case 3.
A seedling tank 10 that reciprocates left and right is provided above and behind the seedling tank 10, and the seedling tank 10 is supported on the upper part of a pair of left and right handle rods 11 attached to the seedling planting transmission case 3.

12 is a soil leveling float, the rear part of which is pivotally connected to the seedling planting transmission case 3 with a pin 13, and the front part of which is connected to the expansion/contraction link 1.
It is installed so that it can move up and down at 4.

Reference numeral 15 denotes running wheels, which are supported on chain cases 17, 17 rotatably mounted around a drive shaft 16 protruding from both left and right sides of the transmission case 2, and are provided to move up and down while being rotated by transmission. There is.

Reference numeral 18 denotes a switching valve of a hydraulic system, and this valve operating arm 19 is connected to the ground leveling float 12 by a rod 2.
When the soil leveling float 12 is located within a predetermined height range suitable for seedling planting work, the oil from the hydraulic pump 6 is directly connected to the hydraulic tank 2.
The hydraulic piston 7b is held in a neutral state returning to 1, and the hydraulic piston 7b is switched from this appropriate height to extend upward, and conversely, when the hydraulic piston 7b moves downward, the hydraulic piston 7b is switched to retract.

22 is a protruding arm, which is attached to the chain case 17,
It was installed on 17. Reference numeral 23 denotes a balance rod, whose left and right middle portions are pivotally connected to the piston 7b. Reference numeral 24 denotes a connecting rod, which interlocks and connects the left and right ends of the balance rod 23 and the protruding arms 22, 22 on each side, and is configured so that the traveling wheels 15, 15 are lowered by the protrusion of the piston 7b. It has been done.

24 is a throttle valve, which is a hydraulic cylinder 7a in the illustrated example.
This is provided in the oil passage A on the side where the piston 7b can be retracted, and is interlocked and connected to the throttle lever 25 that changes the output of the engine 5 with an operating wire 27, and the throttle lever 25 is connected to the high speed side [direction of arrow ] When the rotation operation is performed, the throttle valve 24 is throttled to increase the oil flow resistance, and conversely, when the speed is to be lowered, the opening degree of the throttle valve is increased or fully opened.

Note that this throttle valve 24 is the piston 7b in the embodiment.
Since the capacity of the hydraulic cylinder 7a chamber is small due to It goes without saying that the throttle lever 25 may also be provided in the throttle lever 25 and linked to the throttle lever 25.

Further, in the above embodiment, an embodiment of a walking type rice transplanter was shown, but as shown in FIG.
9, a rice transplanting device as a working device 8 is provided so as to be movable up and down, and a soil leveling float 12a provided at the bottom of this working device 8 switches a hydraulic pressure switching valve 18a to connect the towing vehicle body 28 side and the upper link 29a of the elevating link mechanism.
In this embodiment, a hydraulic cylinder device 30 interposed between the hydraulic cylinder device 30 and the hydraulic cylinder device 30 is actuated to control the lifting and lowering of the working machine 8. Throttle valve 24a linked to the tutle lever 25
Of course, it is also possible to provide a configuration in which

Note that the symbol 31 in the figure indicates a throttle wire.

Next, to explain the operation of the above example, when seedlings are placed in the seedling tank 10 and each rotation part is transmitted by the engine 5, the vehicle body 1 is propelled by the rotation of the running wheels 15, and the lower ground leveling float 12 is moved to soil the soil. Glide across the surface. In addition, the rice transplanting device, which is part of the working machine 8, divides seedlings into individual plants from a seedling tank 10 in which a seedling planting rod 9 reciprocates from side to side, and plants the seedlings on the leveled soil surface.

Seedling planting work is carried out in this way, but when the tiller is uneven and the contact force of the traveling wheels 15 changes, the soil leveling float 12 moves up and down, and the rod 20
The hydraulic switching valve 18 is switched and the hydraulic cylinder device 7 is activated to control the vertical movement of the traveling wheels 15.

Then, the hydraulic switching valve 18 is always switched so that the ground pressure of the soil leveling float 12 is appropriate for seedling planting work, reliable propulsion is obtained, and the seedling planting depth is maintained at an appropriate constant state.

However, when the throttle lever 25 is adjusted to the high speed side, ie, the arrow RO side, in order to increase the efficiency of planting seedlings, the output shaft of the engine 5 naturally rotates at a high speed, which causes the hydraulic pump 6 to rotate at a high speed.

Therefore, the amount of oil discharged from the pump 6 also increases, and the amount of oil that had been sent into the hydraulic cylinder 7a by switching the switching valve 18 by the up and down movement of the soil leveling float 12 increases all at once. The operating speed of the piston 7b becomes rapid. 1st
In the embodiments shown in Figs. 4 to 4, the retraction speed of the piston 7b tends to be rapid.

That is, when the rising speed of the running wheels 15 becomes faster and the movement of the running wheels 15 begins to move upward, as when working at a low speed, the switching valve 18 switches to neutral or the running wheels 15 to the lowering side. Therefore, the next control operation state does not occur before the control is completed, resulting in slow control, and hypersensitive control is performed.

However, in this embodiment, the throttle lever 25
When switching to the high speed side, the throttle valve 24 is throttled by the wire 27, so oil is not rapidly fed into the cylinder 7a and the traveling wheels 15
The operating speed of work equipment 8 can be slowly controlled.
It is possible to eliminate unexpected situations such as hunting phenomenon.

Further, the riding type embodiment shown in FIGS. 5 and 6 is basically the same, but in this case, the switching valve 18a is connected to the ground leveling float 12a.
When moving up, the piston is switched to the protruding side and the lifting link mechanism 20 is rotated upward, causing the work equipment 8 to move upward. Conversely, when the leveling float 12a is moving down, the piston receives the load of the work equipment 8 and retracts. The work equipment can be switched to the side that moves downward.

When the engine is rotated to the high side, the amount of oil supplied into the hydraulic cylinder is restricted by the throttle valve 24a, as in the previous example, so that the upward movement of the work implement 8 does not become rapid.

[Brief explanation of the drawing]

The figures show one embodiment of this invention; Fig. 1 is a partially sectional side view of the invention applied to a walking-type rice transplanter; Fig. 2 is a plan view thereof;
Figure 3 is a side sectional view of the main parts, Figure 4 is a hydraulic circuit diagram,
FIG. 5 is a partially cutaway side view of a riding-type rice transplanter to which the present invention is applied, and FIG. 6 is a hydraulic circuit diagram. Symbols in the diagram: 5 is the engine, 6 is the hydraulic pump, 7
is a hydraulic cylinder device, 7a is a cylinder, 7b
8 is a piston, 8 is a working device, 12 is a leveling float, 18 is a switching valve, and 24 is a throttle valve.

Claims (1)

[Scope of utility model registration request] The switching valve 18 of the hydraulic system is switched by the vertical movement of the soil leveling float 12 that slides on the soil surface, and the hydraulic cylinder system 7 is operated to move the running wheels 15 up and down, or the working device 8 is moved up and down to move the working machine part. In an agricultural machine that controls the water at a substantially constant height relative to the soil surface, there is a throttle lever 25 that changes the output of the engine 5 that drives the hydraulic pump 6 of the hydraulic system, and a throttle lever 25 that changes the output of the engine 5 that drives the hydraulic pump 6 of the hydraulic system. This working machine vertical movement device for an agricultural working machine is constructed by interlocking a throttle valve 24 provided in an oil path sent to a hydraulic cylinder device 7 so that the oil path is narrowed to a small size when the rotation of an engine 5 becomes high speed.