JPH0151963B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a rice transplanting machine, and more specifically,
This invention relates to a rice transplanting machine that can automatically select the lifting speed of the machine.

[Conventional technology]

For example, a riding rice transplanter is constructed by attaching a planting machine to a passenger vehicle body so that it can move up and down.The hydraulic cylinder that supports the planting machine is activated by increasing or decreasing the buoyancy applied to the float of the planting machine. By moving the spool of the oil passage switching valve, the planting machine can always be supported at a constant height relative to the field surface.

[Problem to be solved by the invention]

In a working machine vertical movement mechanism with such a configuration, for example, the upward movement speed is affected by the discharge capacity of the hydraulic pump, so the upward movement speed during rice planting work and when lifting the planting work machine once during rotation are important. It is the same as the upward movement speed. Therefore, if the planting machine is not raised sufficiently and is swung around as it rotates, the float may knock down the already planted seedlings, so it is preferable not to , It is better to move the planting machine up quickly during rounding work, and furthermore,
Even in cases where the tiller is partially deep and the passenger vehicle sinks into the depth, it is desirable to immediately move the planting machine upward.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a rice transplanting machine that can satisfy the various requirements mentioned above.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a float that can move up and down on the underside of a work machine, and a hydraulic lifting mechanism that moves the work machine up and down by changes in the ground pressure of the float. The present invention is characterized by being provided with a hydraulic switching mechanism that increases the lifting speed of the working machine when the ground pressure exceeds a certain value.

[Function] With the above configuration, even if the planting machine sinks into the depths of the tiller, the machine can be quickly moved up and around, and the float can remove the already planted seedlings. Things like defeating them are avoided.

〔Example〕

An embodiment of the present invention will be described below with reference to the accompanying drawings.

First, Fig. 1 shows a riding-type rice transplanter, and reference numeral 1 denotes a passenger vehicle body, and a planting work device 3 is attached to the rear end of this passenger vehicle body 1 via a link mechanism attachment mechanism 2 so as to be able to rise and fall. It's structured well.

The passenger vehicle body 1 has a steering wheel 12 in front of the driver's seat 11, and the output of the engine 13 is directed to the front wheels.
4. The power is transmitted to the rear wheels 15. The mounting mechanism 2 supports the planting machine 3 at the other end of a link 21 whose one end is pivotally supported by the passenger vehicle body 1.
One end of a hydraulic cylinder, which will be described later, is pivotally supported at the end of a rotating arm 22 of the mounting mechanism 2 . The planting machine 3 floats on the field surface and has a float 31 that can move up and down, and the up and down movement of this float 31 determines the position of a switching valve provided in the oil path of a hydraulic cylinder by a push-pullable wire 32. It's summery.

The hydraulic drive source, which is the power source for vertical movement of the planting machine of the mounting mechanism 2, has the following configuration.

As shown in FIGS. 2 and 3, the hydraulic cylinder unit 41 uses a single-acting cylinder, and one end of a piston rod 41a is connected to the end of the rotating arm 22. An oil pump 43 and an oil passage switching valve 44 are provided in the oil passage 42 that supplies pressure oil to the hydraulic cylinder unit 41.
Pressure oil can be supplied to the hydraulic cylinder unit 41 from the oil tank 45.

The switching valve 44 has a direct-acting spool 441,
This spool 441 has an upper hydraulic oil passage 441a and a lower hydraulic oil passage 441b, and has a mechanism for opening and closing a port 442a of a valve body 442 that communicates with an oil passage 42 to the hydraulic cylinder unit 41 through a land 441c. In addition, port 442b connected to oil pump 43, return port 4 to oil tank
It has 42c.

One end of the spool 441 constituting the switching valve 44 is connected to the end of the wire 32 connected to the float 31 of the planting machine 3, and the other end of the spool 441 is connected to the wire 46 via the wire 46. They are each connected to a switching valve operating lever 47 provided near the handle 12. The wire 46 and the spool 441 are connected using a metal fitting 46b having a long hole 46a.
The spool 441 is movable within the elongated hole. Furthermore, the spool 44
Reference numeral 1 denotes a compression spring 48 whose one end is received in a part of the passenger vehicle body 1, and the spring receiver 443 is pressed, and the spring 443 is moved to a half-closed state of the port 442a with respect to the spool 441 as shown in FIG. It gives a habit. This state is when the switching valve operating lever 47 is shifted to a position for planting work. The spring receiver 443 is always in contact with a stopper 443a fixed to the spool 441, which is a snap spring, and only the spring receiver 443 is moved in the direction in which the port 442a is fully closed by a stopper 443b provided on the passenger vehicle body 1 side. Movement is restricted.

Next, actual rice planting work using the riding type rice transplanter of the present invention will be explained. First, during planting, the planting machine 3 is in a state of floating on the field surface by the float 31, the switching valve operating lever 47 is set to the "planting" position, and the state of the spool 441 is as shown in FIG. Oil pump 43 → port 4
42b → upper moving oil passage 441a → port 442a → oil passage 42 communicates, port 442a connects to land 441c
It is kept in a semi-closed state.

Then, if the ground pressure exceeds a certain value when the wheels of the passenger vehicle body 1 sink into the depth of the tiller and the float 31 sinks, the planting machine is quickly raised. have to move. For example, to move the planting machine 3 upward, shift the switching valve operating lever 47 to the "upward movement" position (the wire 46 can be pulled), and the spool 441 moves as shown in FIG. The port 442a is fully opened, pressure oil from the oil pump 43 is rapidly supplied to the hydraulic cylinder unit 41, and the hydraulic cylinder unit 41 is rapidly extended. Due to this extension, the planting machine 3 is quickly moved upward.

Furthermore, when the float 31 suddenly receives a large buoyant force (ground pressure), the push-pull type wire 32 pushes the spool 441 and puts it in the same state as the "up" position of the switching valve operating lever 47 during rotation. Then, the planting machine 3 is quickly moved up.

Furthermore, when the spool 441 is moved from the state in which the planting machine has been moved upward to the top to the "downward movement" position, the lower movement oil passage 441b communicates with the oil passage 42, and furthermore, the port 442c is connected to the oil tank 45. to release pressure oil. oil pump 43
Since the pressure oil from the field returns to the oil tank 45 through the port 442d, the hydraulic cylinder unit 41 contracts and the planting machine 3 is lowered onto the field surface.

〔Effect of the invention〕

As is clear from the above description, the rice transplanting work machine of the present invention has a switching mechanism installed in the oil passage of the hydraulic lifting device that moves the work machine up and down, which changes rapidly when the ground pressure of the float exceeds a certain value. The mechanism is configured to operate the lifting mechanism more rapidly than during normal work, so if the work equipment goes into a deep place, the work equipment can be raised more quickly than during normal planting work, for example. When the aircraft rotates, the float will not knock over the already planted seedlings. In addition, the planting depth of seedlings can be kept almost constant, allowing stable work to be performed.

[Brief explanation of drawings]

The attached drawings show an embodiment of the riding rice transplanter according to the present invention, in which Fig. 1 is a side view, Fig. 2 is an explanatory diagram of the hydraulic piping system of the hydraulic drive source, and Fig. 3 is an operating state of the hydraulic switching valve. FIG. 4 is a cross-sectional explanatory view showing the operating state of the planting work machine when it is in motion. DESCRIPTION OF SYMBOLS 1... Passenger vehicle body, 2... Mounting mechanism, 3... Planting work machine, 41... Hydraulic cylinder unit, 41a
...Piston rod, 42...Oil passage, 43...Oil pump, 44...Switching valve, 441...Spool, 441a...Upper moving oil passage, 441b...Lower moving oil passage, 441c...Land, 442... ...Valve body, 4
42a, 442b, 442c...Port, 443
...Spring holder, 443a, 443b...Stopper.

Claims (1)

[Scope of Claims] 1. A hydraulic lifting mechanism is provided in which a float that can be moved up and down is provided on the underside of a working machine, and the working machine is moved up and down by changes in the ground pressure of this float, wherein the ground pressure of the float is a constant value. In conclusion, the rice transplanting machine is equipped with a hydraulic switching mechanism that increases the lifting speed of the machine.