JP3133461B2 - Rice transplanter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling plant, which is connected to a seedling planting device via a link mechanism so as to be movable up and down, and which is driven by a hydraulic actuator connected via a suspension mechanism to move the seedling planting device up and down. The present invention relates to a rice transplanter configured to be driven.

[0002]

2. Description of the Related Art Conventionally, in the above rice transplanter, as shown in, for example, Japanese Patent Application Laid-Open No. 3-83502, a midway point of a parallel quadruple link mechanism for connecting a seedling planting apparatus so as to be able to move up and down and a body frame. A hydraulic cylinder as a hydraulic actuator is connected therebetween via a coil spring as a suspension mechanism, and a limit switch for detecting a maximum ascending position of the seedling planting device is attached to, for example, a fuselage side bonnet, and the limit switch is connected to a link mechanism. It is configured to detect that it has risen to the maximum ascent position, and the seedling planting device is operated to ascend in the elevating control operation,
There has been a configuration in which, when the limit switch is detected and operated, the hydraulic cylinder is controlled so as to stop the ascending drive immediately.

[0003]

SUMMARY OF THE INVENTION The above-mentioned conventional structure is characterized in that when a seedling plant is raised by driving a hydraulic cylinder,
When the seedling planting device rises to a position close to the mechanical upper limit position, the limit switch detects the rise in order to prevent the hydraulic cylinder from being further raised. However, as described above, if the drive of raising the hydraulic cylinder is configured to be stopped immediately based on the detection by the switch, the traveling body may be vibrated due to, for example, unevenness of the traveling surface in the lift stopped state. In this case, the elasticity of the suspension spring may cause the seedling plant to move relatively up and down, and the detection operating piece of the limit switch may come into contact with or come into contact with the contacting portion of the link mechanism. As a result, the signal for stopping the hydraulic cylinder by the limit switch is turned on and off, and the hydraulic cylinder is intermittently driven, so that an excessive force is applied to the link mechanism or the durability of the hydraulic cylinder control valve is reduced. There was a possibility that adverse effects would occur. An object of the present invention is to eliminate the above disadvantages.

[0004]

According to a feature of the present invention, in the rice transplanter described at the beginning, it is detected by the contact with the link mechanism that the seedling planting device has risen to near the maximum ascent position. A detection switch is provided, and the lifting operation of the hydraulic actuator is stopped in accordance with the detection operation of the detection switch, and after a predetermined time has elapsed from the time when the detection switch started the detection operation, the lifting drive of the hydraulic actuator is performed. Operation delay means for stopping the operation.

[0005]

[Action] Even if the seedling planting device moves up to near the maximum ascending position by driving the hydraulic actuator, and the link mechanism comes into contact with the detection switch to perform the detection operation, the hydraulic cylinder does not stop immediately and the detection time Since the drive is stopped after a lapse of a predetermined time from the start, the seedling planting device slightly rises even after the link mechanism first contacts the detection switch, so that the hydraulic actuator is stopped, and the elastic force of the suspension mechanism is reduced. As a result, even if the relative position of the seedling placement apparatus with respect to the machine body slightly changes, the detection switch maintains the detection operation.

[0006]

Therefore, even if a suspension mechanism is interposed to smoothly drive the raising and lowering of the seedling planting device by the hydraulic actuator, even when the seedling planting device is stopped near the maximum rising position, The possibility that the intermittent driving state of the hydraulic actuator appears can be reduced, and the durability of the link mechanism and the hydraulic control system can be improved.

[0007]

Embodiments will be described below with reference to the drawings. FIG.
Shows a riding rice transplanter. The rice transplanter can be raised and lowered at the rear of the riding type traveling body via a parallel four-link mechanism 1 and can freely roll left and right around the longitudinal axis.
Are connected. The seedling planting device 2 pivotally supports a planting transmission case 4 that is also used as a frame so as to be rotatable around a longitudinal axis Y on a pivot boss 3 provided on the rear link 1a of the link mechanism 1. In a case 4, a seedling rest 5 which reciprocates sideways with a constant stroke, a plurality of planting mechanisms 6 for taking out seedlings for planting one by one from the lower end of the seedling rest 5 and planting them in a field, 3 are arranged in parallel on the left and right sides Grounding floats 7
And the like. The hydraulic cylinder 10 [an example of a hydraulic actuator] connected between a midway portion of the link mechanism 1 and the body frame 8 via a suspension spring 9 [an example of a suspension mechanism] is moved up and down by expansion and contraction driving. And an electric motor M and a screw feed mechanism 11 provided between the rear link 1a and the back side of the seedling rest 5 so as to operate.
The rolling operation is performed by a rolling operation mechanism 12 composed of the following. The hydraulic control valve V for the hydraulic cylinder 10 is configured to be of an electromagnetic type, and the electromagnetic control valve V is configured to be driven and controlled by a control device 13 including a microcomputer. That is,
As shown in FIG. 1, an operation of raising and lowering operation and a neutral stop state can be artificially performed by operating an elevating lever 16 disposed on the side of the driver's seat 15 of the airframe operation unit 14. A push operation type up / down switch SW1 provided on the panel 17 is configured so that an up operation and a down operation can alternately appear. Further, when the reverse detection switch SW2 detects that the shift operation lever 19 of the gear type main transmission 18 of the traveling machine body has been operated to the reverse position, the operation is automatically set to the ascending operation state. In the planting operation state, the control device 13 is provided with a lifting control means A for maintaining the height of the seedling planting device 2 above the ground at a predetermined value in a control program format. That is, the ground float 7 at the center in the left and right directions is supported so as to be able to swing up and down around the rear fulcrum, and the relative position of the ground float 7 on the front side of the ground float 7 with the change of the ground height of the seedling planting device 2 is changed. Link 20 up and down
The control device 13 detects the electromagnetic control valve V of the hydraulic cylinder 10 so that the output value of the potentiometer PM falls within a predetermined set area.
To maintain the seedling planting apparatus 2 at a predetermined ground height. When the raising and lowering switch SW1 and the reverse detection switch SW2 are actuated to raise the seedling planting device 2 to the maximum rising position, a limit for detecting that the seedling planting device 2 has risen to near the maximum rising position. Switch SW3
[Example of the detection switch] is the rear fender unit 2 of the traveling body.
1, the link mechanism 1 is configured to perform a detection operation by contacting an intermediate portion of the link mechanism 1 with the ascending operation, and the ascending-side drive of the hydraulic cylinder 10 is automatically stopped based on the detection operation of the limit switch SW3. It is composed. An operation delay means B for stopping the ascending drive of the hydraulic cylinder 10 is provided in the control device 13 in the form of a control program after a predetermined time has elapsed from the time when the limit switch SW3 starts the detection operation. That is, as shown in FIGS. 2 and 3, the detection piece 22 of the limit switch SW3 is arranged so as to be in contact with the side surface of the upper link 1b in the link mechanism 1 to perform the detection operation. Even when the switch 1b comes into contact with the detection piece 22 and the switch SW3 is turned on, the detection piece 22 contacts the side surface of the upper link 1b so as to be able to continue ascending. Then, the control device 13 is configured to control the switching of the electromagnetic control valve V from the ascending drive position to the neutral stop position after a lapse of a predetermined short time from the time when the detection signal is given from the limit switch SW3. In this manner, even when the seedling planting apparatus 2 vibrates up and down by the action of the suspension spring 9 in a state where the lifting operation is stopped, the detection piece 22 of the limit switch SW3 abuts on the side surface of the upper link 1b. Since the switch SW3 is turned on and off unexpectedly, the electromagnetic control valve V is repeatedly turned on and off in a short time, and an adverse force such as an excessive force applied to the link mechanism 1 can be prevented. It will be.

[0008] In the claims, reference numerals are written to facilitate comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[Brief description of the drawings]

FIG. 1 is a control block diagram

FIG. 2 is a side view of a detection switch mounting portion.

FIG. 3 is a cutaway front view of a detection switch mounting portion.

FIG. 4 is an overall side view of the rice transplanter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Link mechanism 2 Seedling plant 9 Suspension mechanism 10 Hydraulic actuator B Operation delay means SW3 Detection switch

Claims (1)

(57) [Claims] A hydraulic actuator (1) connected to a traveling machine body via a link mechanism (1) so as to be able to ascend and descend via a link mechanism (1), and connected via a suspension mechanism (9).
0) The rice transplanter configured to drive the seedling planting device (2) up and down by the drive of 0), wherein the raising of the seedling planting device (2) to near the maximum ascent position is performed by the link mechanism. A detection switch (SW3) for detecting by contact with (1) is provided, and the lifting operation of the hydraulic actuator (10) is stopped along with the detection operation of the detection switch (SW3), and the detection switch A rice transplanter comprising an operation delay means (B) for stopping the ascending drive of the hydraulic actuator (10) after a lapse of a predetermined time from the point when (SW3) starts the detection operation.