JPS63267202A - Rise and fall control device for working machine in agricultural operation machine for paddy field - Google Patents

Abstract

PURPOSE:To always carry out rise and fall control of working machine in high accuracy continuously, by controlling addition and reduction of pressure of hydraulic oil to be sent from a hydraulic pump to a rise and fall cylinder for working machine depending upon earth contact pressure of earth contact material. CONSTITUTION:While working, standard value of earth contact pressure is successively obtained from a set value of a setting device 123 of earth contact pressure and a detected value of a surface soil hardness sensor 67, the standard value is compared with the average detected value of practical earth contact pressure sensors 81L and 81R and a pressure control valve 102 is regulated based on the result. For example, when the detected value is smaller than the standard value, inner pressure of a lift cylinder is lowered until the detected value is in accordance with the standard value. When the detected value is larger the standard value, the inner pressure of the light cylinder is raised. The detected values of the left and the right earth contact pressure sensors 81L and 81R are mutually compared and pressure control valves 103 and 104 are regulated in such a way that both the values become equal. The result of the control is used for the next detected values of the earth contact pressure sensors 81L and 81R for feedback.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a hydraulic working machine elevation control device for holding the working machine at an appropriate height in a paddy field agricultural working machine such as a riding rice transplanter.

[Prior art 1] A working equipment lifting control device for a conventional rice paddy agricultural working machine in which a working equipment such as a rice transplanter or a seeding machine having a float is attached to a passenger tow vehicle body via a hydraulic lifting device is based on a grounding body such as a float. The height of the work equipment can be adjusted by operating the hydraulic switching valve installed in the hydraulic oil path of the hydraulic system depending on the ground pressure, and supplying, draining, or stopping the hydraulic oil to the hydraulic cylinder for raising and lowering the work equipment. was supposed to be controlled.

[Problems to be solved by the invention] However, since it is not possible to switch the supply direction of hydraulic oil in a short time, the elevation control of the work equipment cannot follow changes in the topsoil surface of the paddy field during high-speed work. There was a problem. Furthermore, since the working machine is moved up and down intermittently, there is also the problem that hunting occurs when synchronized with vibrations caused by rotation of running wheels, etc.

For this reason, highly accurate elevation control cannot be expected, and especially in the case of rice transplanters, there has been a problem in that the seedling planting depth varies.

[Means for Solving the Problems] In order to solve the above problems, the present invention employs the following configuration.

That is, the working machine lifting control device for a paddy field agricultural working machine according to the present invention is a working machine lifting control device for a paddy field working machine that hydraulically raises and lowers the working machine according to the ground pressure of a grounding body that is in contact with the topsoil surface of a paddy field. The hydraulic system is characterized in that the hydraulic system is configured to increase or decrease the hydraulic pressure supplied from the hydraulic pump to the cylinder for lifting and lowering the working machine in accordance with the ground pressure of the grounding body.

[Function] The hydraulic pressure supplied from the hydraulic pump to the cylinder for lifting and lowering the work equipment is controlled by a pressure control valve, etc., so it is possible to maintain a continuous lifting control state at all times, and to keep the pressure inside the cylinder at the level of the grounding body. It is possible to always maintain the appropriate value determined from the ground pressure, and it is possible to perform highly accurate lifting and lowering control of the work equipment in accordance with changes in the topsoil surface of the paddy field.

[Embodiment] Each of the figures below FIG. 1 shows one embodiment of the present invention, and the illustrated paddy field agricultural machine 1 is a self-propelled tractor 2.
A rice transplanter 3, which is a working machine, is attached to a link device 4 for lifting and lowering the working machine provided at the rear end, and the rice transplanter 3, which is a working machine as a whole, is configured as a riding type rice transplanter. A seeding machine etc. may also be used.

The towing vehicle 2 includes a transmission frame 6 extending rearward at the rear of a transmission case 5, and front wheels 8.8 are supported by front wheel support cases 9.9 provided on both sides of the transmission case 5 so as to be able to change direction. The rear wheel 11.11 is pivotally supported by the tip of a transmission case 12.12 attached to the rear end of the transmission frame 6. The engine 14 is installed on the upper part of the frame 6, and a seat 15 is installed on a box-shaped cover that covers the engine 14.

The link device 4 includes two upper links 23, 23 and two lower links 24, 24 rotatably supported by a support frame 22 fixed to the integral moving frame 6, with the rear ends of the upper and lower links being rotatably supported. A work implement coupling device 25 is attached to the section.

Reference numeral 26 designates a hydraulic cylinder (hereinafter referred to as a lift cylinder) for lifting and lowering the working machine of this link device, whose base is pivotally attached to the support frame 22, and whose piston rod tip 26a is connected to the upper link 2.
It is rotatably attached to a connecting rod 27 that connects the intermediate portions of 3.23, and by expanding and contracting this, the link device 4 can be rotated up and down. The amount of rotation is detected by a water machine height sensor 29 having an arm 29a rotated by a rod 28 attached to a lower link (or an upper link).

The work equipment coupling device 25 has a rolling pin 31 supported by bearings 31a provided front and rear at the lower part of a box-shaped bracket (link side member) 30 on the side of the upper and lower links 23 and 24, and a pitch plate at the tip of the rolling pin 31. A (work machine side member) 32 is provided facing the bracket 30 and fixed thereto. A pair of left and right work machine mounting plates 33 protruding from the back surface of the pitch plate 32 are provided with pin engaging portions 33a for mounting the work machine at upper and lower positions, respectively. A working machine rolling hydraulic cylinder 35 (hereinafter referred to as a rolling cylinder) is installed horizontally on the upper part of the bracket 30, and the tip of the rolling cylinder 35 is connected to the left and right center of the pitch plate 32 by connecting pins 36, 37 and connecting links 38. is connected to the top of the Additionally, there is a bracket (3) at the tip of the rolling cylinder 35.
The tip of a swing arm 40 pivotally attached to the bracket 30 is connected to the swing arm 40, and a loft 42 of a rolling sensor 41 provided on the bracket 30 is attached to the middle part of the swing arm 40. This rolling sensor 41 detects the amount of inclination of the working device in the left-right direction with respect to the towing vehicle 2 . In some cases, the swing arm 40 and rolling sensor 41 may be omitted.

Furthermore, this work equipment coupling device 25 includes a bracket 30.
A lock pin 43 is pivotally attached to the front of the upper part of the lock pin, a lock pin push rod 44 is provided hanging down from the middle part of the lock pin, and the rod 4 is fixed to the lower link 24.
4, a spring 46 provided between the bracket 30 and the rod 44 to urge the rod 44 downward, and a spring 46 formed at the upper ends of the bracket 30 and the hitch plate 32. Positioning recess 47, 4
A rolling lock mechanism 49 consisting of 8 and 8 is provided. The positioning recesses 47 and 48 are provided so that when they match, the working machine will not tilt with respect to the towing vehicle body.

The rice transplanter 3 has a seedling tank 51 tilted above the transmission case 50 so that the front side is on top.
Branch case 54 from the bottom of the case. ... are respectively extended rearward, and each branch case 54. Planting device 55.・
... is installed. Central branch case 54 (C
) has one on each side, and left and right branch cases 54 (L), (
R) is equipped with a total of five planting devices 55, one on each side, and this rice transplanter 3 is configured as a five-row rice transplanter. The planting device M55 is provided with planting rods 57 and 57 that also rotate at both ends of the rotating case 56.

The planting claws 58, 58 of these pair of planting rods move up and down while drawing a predetermined trajectory, taking out seedlings one by one from the seedbed placed in the seedling tank 51 and planting them alternately in the paddy field. It's starting to go. Taue R3 is transmission case 50
The mounting provided on the front part of the is pin 60. The pitch plate 32 is attached to the towing vehicle 2 by engaging with the pin engaging portions 33a, . At the same time, power is transmitted to the PTO shaft 6 and the wheelbase 1 of the towing vehicle 2.

This rice planting A3 uses a center float 63 (C) and a pair of left and right side floats 63 as grounding bodies for the topsoil surface of the paddy field.
(L) and (R) are provided. These floats 63 are each supported so as to be able to rotate up and down, and their front portions are suspended from the branch case 54 by expansion/contraction links 65. In addition, side float 63
(L) and (R) are connected to the branch case 54 indirectly via a ground pressure detection device 64 which also serves as a planting depth adjustment device. ...
is attached to. In addition, side float 63 (
A topsoil hardness sensor 67 for detecting the hardness of the paddy topsoil surface is provided at the center of the bottom of L) and (R).

In the ground pressure detection device 64, a planting depth adjustment member 69 is attached to a mounting piece 70 integrated with the transmission case 54 by a shaft 71, and its mounting angle is determined by a planting depth adjustment lever 72.
It is adjustable by. Planting depth adjustment member 69
A lever rod 73 is pivotally mounted to the rear end portion by a support shaft 74 so as to be able to swing up and down. This lever 73 is
A mounting member 76 of the float 63 is connected to the vicinity of the support shaft 74 by a connecting pin 77, and its tip is elastically supported by a downwardly biased spring 79. In addition, a contact pin 80 that loosely fits into the spring 79 is fixed upward to the tip of the lever 73, and the tip of the contact pin 80 is connected to the stroke-type ground pressure provided at the top of the planting depth yJ joint member 69. It is in contact with the detection rod 81a of the sensor 81 via a sealing material 83. Note that 84 in the figure is a stopper that regulates the lower limit position of the bar 73.

The force that the float 63 receives from the topsoil surface of the paddy field is transmitted to the lever rod 73 via the connecting pin 77 that is the point of action, and the lever rod 73 resists the repulsive force of the spring 79 and moves around the support shaft 74 that is the fulcrum. swing upwards. Along with this, the detection rod 81a is pushed upward by the contact pin 8O, which is the force point, so that the yield i of the spring 79 that generates the ground pressure is detected by the ground pressure sensor 81 as a stroke. Since the distance JtL from the fulcrum to the point of force is much larger than the distance B from the fulcrum to the point of application, even the slightest movement of the float 63 is amplified and appears in the contact bin 80, making it possible to accurately detect ground pressure. is now possible.

In addition, since the entire device of the ground pressure detection device 64 is integrated with the planting depth adjustment member 69, the planting depth of the seedlings can be changed by rotating the planting depth adjustment member 69. There is no appreciable effect on ground pressure detection.

Next, FIG. 7 is a hydraulic circuit diagram showing the hydraulic system of this paddy field agricultural machine 1. The hydraulic system 100 is configured such that the internal pressure of the lift cylinder 26 and the rolling cylinder 35 is maintained at a predetermined level by the pressure control valves 102, 103, and 104. It is adjusted to the pressure. Note that the pressure control valves 103, 10
4 are linked to each other so that the supply of hydraulic oil to the rolling cylinder 35 and the restoration to the tank 105 are performed in opposite directions. The hydraulic oil path to the lift cylinder 26 includes a poppet valve 106 and a check valve 107.
is provided. In addition, a constant pressure valve 1 is provided on the pump 109 side.
10 and an accumulator 111 are provided. These 110, 111 are pressure control valves 102, 103, 10
Although the pressure on the pump side of No. 4 is always maintained at a high value, other methods may be used to ensure the pressure.

The control device 120 that controls the hydraulic system 100 has an eighth
As shown in the figure, the controller 121 has a ground pressure setting device 1.
23, command signals from the manual raise and lower switches 125 and 126, the water height sensor 28, the rolling sensor 35, the topsoil hardness sensor 67, and the left and right ground pressure sensors 81 ( Detection signals from L) and (R) are input, and these signals are sent to controller 1.
21, the pressure control valves 102, 103
．． An actuation command signal is issued to 104 and poppet valve 106 .

That is, during work, the reference value of the ground pressure is sequentially determined from the set value of the ground pressure setting device 123 and the detected value of the topsoil hardness sensor 67, and this and the actual ground pressure sensor 81 (L), (R) are used.
For example, if the detected value is lower than the reference value, the internal pressure of the lift cylinder 26 is increased until the detected value matches the reference value. On the other hand, if the detected value is high, the internal pressure of the lift cylinder 26 is increased. Further, the detection values of the left and right ground pressure sensors 81 (L) and (R) are compared with each other, and the pressure control valves 103 and 104 are controlled so that the values are equal. The results of these controls are used for the next ground pressure sensor 81.
This is fed back to the detected values of (L) and (R).

If you only think about lifting control, side float 63
Instead of providing ground pressure sensors for each of (L) and (R), only one ground pressure sensor may be provided for the center float 63 (C), and the detected value thereof may be compared with the reference value.

During work, the lower link 24 is in the forward upward position, so the strike plate 4
5 pushes the lock bin push rod 44 upward. Therefore, the lock bin 43 is out of the positioning recess 47, 48, and the pitch plate 32 can freely rotate relative to the bracket 30. Therefore, by adjusting the internal pressure of the rolling cylinder 35 with the pressure control valves 103 and 104,
Effective rolling control is provided.

As the lower link 24 approaches the horizontal position from the forward upward position, the amount by which the lock bin push rod 44 is pushed up by the catch seat 45 decreases. , 48, and the bracket 30 and hitch plate 32 are coupled and integrated. Therefore, the rotation of the pitch plate 32 with respect to the bracket 30 is restricted, resulting in a locked state, and the rice transplanter 3
is maintained in a predetermined position without tilting with respect to the towing vehicle body. Since a spring 46 is attached to the lock bin push rod 44 to bias it downward, the engagement of the four positioning parts 47, 48 of the lock bin 43 is ensured. Conversely, when transitioning from the non-working state to the working state, the lock bin 43 is removed from the positioning recess 47, 48 when the height is below a predetermined height, and the rolling lock is released.

Furthermore, when the water transplanter height sensor 28 detects that the rice transplanter 3 has risen above a certain height and is in a non-working state, the poppet valve 106 is "closed" and the lift cylinder 25 is closed. locked in position.

For this reason, the rice transplanter is prevented from unexpectedly descending when ascending.

The illustrated example of a paddy field agricultural working machine 1 is provided with a rolling lock mechanism 49 that mechanically locks and unlocks the rolling of the working machine due to the vertical movement of the link device. The rolling lock may be performed hydraulically based on the above.

In this embodiment, a riding-type paddy field agricultural working machine that pulls the working machine with a towing vehicle has been described. However, for example, a walking-type paddy field working machine with a body that can roll in the left and right directions with respect to the running wheels may also be used. The same is true.

Furthermore, the present invention is applicable not only to agricultural machines for paddy fields, but also to tractors, etc.! ) It is also conceivable that it could be adopted as a work equipment lifting control device for machines.

[Effects of the Invention] As is clear from the above description, the working machine elevation control device for a paddy field agricultural machine according to the present invention quickly responds to the condition of the paddy field topsoil, and can smoothly control the working machine elevation. This makes it possible to perform high-precision lifting and lowering control, making it possible to maintain good working conditions.

[Brief explanation of the drawing]

Fig. 1 is a side view of a paddy field agricultural machine to which the present invention is applied;
The figure is a plan view, Figures 3 and 4 are side and rear views of the main parts, and Figures 5 (a), (b), and (c) are rear views, side views, and plane views of the work equipment coupling device. 6 is a side view of the float and the planting depth adjustment device, FIG. 7 is a hydraulic circuit diagram of the hydraulic system, and FIG. 8 is an explanatory diagram of a block diagram of the control device. 1...Agricultural machine for paddy fields 2...Tow vehicle 3...Rice transplanter (work machine) 20...Link device 25...
・Work equipment connection device 26...lift cylinder 32
... Rolling cylinder 63 ... Float 67
...Planting depth adjustment device 81...Ground pressure sensor l
OO... Hydraulic device 102, 103, 104... Pressure control valve 120... Control device

Claims (1)

[Claims] (1) A work machine lifting control device for a paddy field agricultural machine that hydraulically raises and lowers the work machine according to the ground pressure of a grounding body that is in contact with the surface of the topsoil of a paddy field, wherein 1. A work machine lifting control device, characterized in that a hydraulic device is configured to control increase/decrease of hydraulic pressure supplied to a work machine lifting cylinder.