JPH0767340B2 - Hydraulic control device for paddy work machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hydraulic control device for a paddy work machine such as a riding type rice transplanter, a seeder, a fertilizer, and the like, in which a working unit is vertically movable. It is related to.

[Problems to be Solved by Prior Art and Invention] Generally, in this type of paddy work machine, vertical movement control of a working unit is performed by hydraulic actuation by expansion and contraction of a hydraulic cylinder accompanying drive of a hydraulic pump. There is. Then, the paddy work machine controls the hydraulic operation by controlling the ground pressure from the paddy field by the float provided in the working section to control the vertical movement of the working section, and even if the traveling machine body travels on the uneven cultivator. It is considered that the working unit takes a substantially constant working posture with respect to the rice field.

In such a case, when the working unit is moved up and down by detecting the ground pressure constantly regardless of the change in the traveling speed, the working unit that follows the sensing of the ground pressure of the float can move vertically when the traveling speed is high. As it goes too far, the vertical movement of the working part changes drastically, causing a so-called pitching phenomenon,
If the vertical movement of the working unit is delayed to accommodate this,
When the traveling speed is slow, the followability of the working unit is impaired.

Therefore, in order to avoid this, it is proposed that the sensitivity of the vertical movement associated with the detection of the ground pressure of the working unit is made insensitive at high speed running and sensitive at low speed running. However, this method only adjusts the sensitivity (valve switching timing) of valve switching for supplying pressure oil to the hydraulic cylinder, and changes the amount of pressure oil supplied to the hydraulic cylinder after switching. Therefore, when the sensitivity is adjusted so that it is suitable for high-speed traveling, the vertical movement start timing of the working unit is too late and the followability is impaired. There is a problem in that the vertical movement of the working unit until the speed is high is still too violent and the pitching phenomenon cannot be eliminated.

[Means for Solving the Problem] The present invention has been conceived with the object of providing a hydraulic control device for a paddy working machine capable of eliminating these drawbacks in view of the above circumstances. In a paddy work machine in which vertical movement control of a working unit provided on a traveling machine body is performed by expanding and contracting a hydraulic cylinder associated with the supply of pressure oil from a hydraulic pump, the hydraulic oil supply amount of the hydraulic pump is adjusted to be increased or decreased. It is possible to adjust the pressure oil supply amount of the hydraulic pump so that when the traveling speed is switched to a high speed, the pressure oil supply amount is reduced and the traveling speed is switched to a low speed as compared with the traveling speed of the traveling machine body. It is characterized in that they are connected so that the pressure oil supply amount increases in the case of the above.

According to the present invention, the vertical movement control of the working section can be performed at a speed commensurate with the working speed of the traveling machine body.

[Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings. In the drawings, reference numeral 1 denotes a traveling machine body of a riding type rice transplanter, and a planting section 2 is attached to the rear of the traveling machine body 1 via a link mechanism 3 so as to be vertically movable. Then, the planting claw 4 in the working unit 2 which is timed to the traveling speed of the traveling body 1
It is the same as the conventional method that the seedlings 5 are planted on the paddy field by scraping off the seedlings for the unit planting stock by the planting operation of.

Reference numeral 6 denotes a float provided on the planting part 2 so as to be vertically swingable via a rear support shaft 6a. The front part of the float 6 has an adjuster link 7, a connecting lever 7a, provided on the planting frame 2a. The traveling vehicle body 1 via the connecting mechanism such as the connecting link 8
It is interlockingly connected to one end of a detection arm 9 which swings about a support shaft 9a provided on the side. A rear end of the operating lever 10 is pivotally connected to the other end of the detection arm 9, and the front end of the operating lever 10 is connected to the switching arm 11a of the hydraulic valve 11.
Are linked to. Then, the planting part 2 tends to sink, and the ground pressure sensing received by the float 6 becomes high, and the float 6
When the robot 6 moves upward with the support shaft 6a as the fulcrum, the hydraulic valve 11 is switched to the upward side by the continuous movement of the support shaft 6a, whereby the hydraulic cylinder 12 is extended and the working unit 2 is raised.
On the contrary, when the planting part 2 tends to rise and the ground pressure of the float 6 becomes low, the hydraulic valve 11 is switched to the lower side this time, and the working part 2 descends. Up-and-down movement control of the planting part 2 associated with sensing of the ground pressure of the float 6 is performed so that the work posture with respect to the paddy field can be maintained substantially constant.

Reference numeral 13 denotes a hydraulic pump, and an operating shaft 13a of the hydraulic pump 13
There are two types of driven pulleys 14 and 15 of large and small.
On the other hand, the drive shaft 16a of the engine 16 mounted on the traveling body 1
Shows that the drive pulleys 17, 18, 19, and 20 having the same diameter are integrally supported by the drive pulley 1.
7, 18 and the driven pulleys 14, 15 between the transmission belts 21, 2
2 are each suspended and also drive pulleys 19, 20
The transmission belts 26 and 27 are respectively suspended between the two large and small driven pulleys 24 and 25 on the side of the transmission case 23 of the traveling machine body 1.

Tension pulleys 28, 29, 30 and 31 are respectively installed opposite to the transmission belts 21, 22, 26 and 27, but the transmission belt 21 suspended on the small diameter driven pulley 14 on the hydraulic pump 13 side.
And a large diameter driven pulley 25 on the side of the transmission case 23.
A tension pulley opposite the suspension transmission belt 27
28 and 31 are boss shafts whose tension arms 28a and 31a are the same.
It protrudes from 32 and it is designed to work together,
In addition, the transmission belt 22 on the large diameter driven pulley 15 side of the hydraulic pump
And the tension arms 29a and 30a of the tension pulleys 29 and 30 that are installed opposite to the transmission belt 26 on the small diameter driven pulley 24 side of the transmission case, project from the same boss shaft 33 and operate integrally. ing. Then, when the power transmission from the engine 16 to the transmission case 23 is switched to the high-speed running side by the switching operation of the main shift operation lever 34, that is, the transmission belt 26 on the small diameter driven pulley 24 side.
When the tension is tightened, the power transmission to the hydraulic pump 13 in connection with this becomes a power transmission state at a low speed performed via the large diameter driven pulley 15, and the pressure oil supply amount decreases, and conversely, When the power transmission to the transmission case 23 is switched to the low speed traveling side, that is, when the transmission belt 27 on the large diameter driven pulley 25 side is tightened, the hydraulic pump is linked to this.
The power transmission to 13 is configured so that the high speed power transmission is performed via the small diameter driven pulley 14 and the pressure oil supply amount increases.

In the embodiment of the present invention configured as described above, the transmission 23 receives the power associated with the driving of the engine 16 to cause the machine body to travel and the planting unit 2 to plant. However, in this case, when the main shift operation lever 34 is operated to the high speed running side, the hydraulic pump 13 is in a low speed drive state, and when the main shift operation lever 34 is operated to the low speed running side, The hydraulic pump 13 is switched to the high speed drive state.

That is, in this structure, when the main gear shift operation lever 34 is switched to the high-speed running side, the large-diameter driven pulley 15 causes low-speed power transmission to the hydraulic pump 13, as described above. When the main gearshift operation lever 34 is switched to the low speed running side, the hydraulic pump 13 operates on the small diameter driven pulley.
High-speed power transmission by 14 will be performed. Therefore, during high-speed work traveling, the hydraulic pump 13 becomes low in speed and the pressure oil supply amount decreases, and the planting section 2 is controlled to move up and down in a slow speed. The occurrence of the phenomenon will be surely suppressed.

Further, when the vehicle is traveling at a low speed, the hydraulic pump 13 becomes high in speed and the discharge speed increases, and the planting unit 2 has a high vertical movement speed, that is, a highly sensitive vertical movement control. Thus, the discharge speed of the hydraulic pump 13 is automatically switched between low speed and high speed in response to changes in the working speed between high speed and low speed, and the vertical movement speed of the planting part 2 changes according to the traveling speed. Therefore, the rice field following ability of the planting section 2 is significantly improved regardless of the change in traveling speed, and the working posture of the planting section 2 with respect to the rice field can be maintained substantially constant and tidy. The planting work can be done. Moreover, since the discharge speed of the hydraulic pump 13 is automatically switched in connection with the switching operation of the traveling speed, this one does not require a separate and complicated lever operation. There is also the advantage that it is convenient.

It should be noted that the present invention is not limited to the above-mentioned embodiment, and the discharge speed switching of the hydraulic pump may be performed in three stages or more instead of two stages. The relationship with the traveling speed is such that the ejection speed decreases when the traveling speed is switched to a high speed and the ejection speed increases when the traveling speed is switched to a low speed. Anything as good as it can be. Further, as in the embodiment, the float 6 is configured so that its mounting position can be adjusted back and forth, which is convenient because the sensitivity of the float can be adjusted according to the field conditions.

[Operation] In short, since the present invention is configured as described above, the vertical movement control of the working unit reduces the amount of pressure oil supplied from the hydraulic pump when the high-speed traveling state is switched to the hydraulic cylinder. When the expansion / contraction speed is slow, and when the vehicle is switched to the low speed running state, the hydraulic oil supply amount is large and the expansion / contraction speed of the hydraulic cylinder is high. It is possible to automatically change and adjust the vertical movement speed of the working unit corresponding to. As a result, when the traveling speed changes to high or low, the working unit is moved up and down at a speed corresponding to the traveling speed. It is possible to suppress the deterioration of the flat surface followability during traveling, which makes it possible to improve the maintenance of the working posture of the working unit with respect to the flat surface and improve the working accuracy.

Moreover, since the pressure oil supply amount of the hydraulic pump is automatically adjusted in association with the switching of the traveling speed, there is no need for a separate operation for adjusting the pressure oil supply amount, and the operability is bothersome. It will not be complicated.

[Brief description of drawings]

The drawings show an embodiment of a hydraulic control device for a paddy field working machine according to the present invention, in which FIG. 1 is a side view of an entire riding-type rice transplanter, FIG. 2 is a side view of essential parts, and FIG. FIG. 4 is a schematic plan view of the transmission mechanism, and FIG. 4 is a schematic front view of the high speed traveling transmission mechanism and the low speed traveling transmission mechanism. In the figure, 1 is a traveling machine body, 2 is a planting part, 6 is a float, and 13 is a hydraulic pump.

Claims (1)

[Claims] 1. A vertical movement control of a working unit provided on a traveling body,
In a paddy work machine configured to perform expansion / contraction operation of a hydraulic cylinder associated with the supply of pressure oil from a hydraulic pump, the pressure oil supply amount of the hydraulic pump can be increased / decreased, and the pressure oil supply amount of the hydraulic pump can be adjusted. In connection with the switching of the traveling speed of the traveling machine body, the pressure oil supply amount should be reduced when the traveling speed is switched to high speed, and the pressure oil supply amount should be increased when the traveling speed is switched to low speed. A hydraulic control device for a paddy work machine.