JPH0442981Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a hydraulic control device for rice field working machines such as rice transplanters and flooded direct sowing machines.

Conventional technology In rice field working machines, for example, riding rice transplanters,
The working machine (planting section) is raised and lowered using hydraulic pressure, and the raising and lowering movement can generally be controlled both manually using a hydraulic control lever and automatically using float sensing. Automatic control based on float sensing normally detects vertical fluctuations based on changes in soil pressure from the field surface relative to the float, and switches and operates the elevation control device via an operating mechanism. For example, the float is connected to a switching arm of a hydraulic valve via a hydraulic pressure sensing lever, a swing arm, a sensor rod, etc., which are connected in sequence to the float in the form of a link. In order to prevent the link mechanism from being damaged due to the sudden rise of the float, a relief mechanism using an elongated hole is usually provided in the link mechanism.

Problems to be solved by the invention However, as shown in FIGS. 7 and 8, in the conventional device, one end side of the sensor rod that constitutes a part of the actuation mechanism L is connected to the fulcrum via the elongated hole L and the pin H. It is pivotally connected to the swinging armho which rotates around the shaft, and since a spring is tensioned between the pin of the sensor rod and the pin of the swinging armho, the swinging armho controls the vertical movement of the hydraulic pressure sensing lever. (responses to the vertical movement of the float), rotational friction occurs between the hook part of the spring and the pin part each time it rotates, and this friction increases link resistance, resulting in slow hydraulic pressure sensing. There were some problems.

Means for Solving the Problems Therefore, the present invention aims to improve the operating mechanism of the elevation control device by
Hydraulic pressure sensing lever, swing arm, etc. connected to the float side, and sensor rod connected to the control device side.
The swing arm and the sensor rod are pivotally connected to each other, and the sensor rod is divided into parts so as to be extendable and retractable within a predetermined range, and each of the divided rod members is connected via a spring. By biasing the sensor rod in the shortening direction, the above-mentioned problem is solved by allowing the relief mechanism to function as effectively as before, which prevents damage to the link mechanism caused by the sudden rise of the float. It is.

Operation Since the hook part of the spring does not touch the rotating part of the pin of the swing arm like in conventional models, there is no rotational friction between the spring and the pin, which reduces the hydraulic pressure sensing load, resulting in more stable hydraulic sensing. can be done.

Embodiment 1 is a cam plate rotatably supported via a cam shaft 3 to a U-shaped frame 2 fixed to the body of a riding rice transplanter, and a hydraulic operating arm (described later) is pivotally supported on the outer periphery of the cam plate. It is pressed by an upper roller 18 and a lower roller 7 pivotally supported by a planting clutch arm, which will be described later.

4 is a hydraulic operating lever, the base end of which is connected to the cam plate 1
It is connected by a pin 5 to the cam plate 1, and rotates integrally with the cam plate 1 around the cam shaft 3, from the rear of the fuselage (right side in Figure 2) to the front (left side).
The hydraulic pressure is set in sequence to "up" position A, "neutral" position B, "automatic lowering/clutch OFF" position C, and "automatic lowering/clutch ON" position D. Reference numeral 6 denotes a bracket which is inserted into the space of the U-shaped frame 2 and is pivotally supported on the camshaft 3. On the bracket 6, a planting clutch arm 8 with a roller 7 pivotally supported at the rear end is attached to a support shaft 9. It is rotatably attached to the planting clutch 11, and its tip is connected to the planting clutch 11 via a wire 10 and a bullet 12. The planting clutch 11 is always urged toward the clutch ON side by a bullet (not shown).

Numeral 13 is a planting clutch lever, the base end of which is fixed to plate 13'. The plate 13' is supported at one end by the camshaft 3 and at the other end by the support shaft 9, and elastically biased against the inner wall surface on one side of the bracket 6 by a compression elastic machine a. The planting clutch lever 13 is normally located in the engagement groove 13' of the guide hole 13a.
The clutch is held in the OFF position by a.
Remove the lever 13 from the engagement groove 13'a and slightly
Bracket 6 connects to camshaft 3 by simply moving it in the ON direction.
The roller 7 moves along the cam plate 1, loosens the wire 10, and turns the planting clutch 11 ON.

14 is a hydraulically operated arm, the rear end of which is attached to the frame 2.
The arm 14 is rotatably supported via a support shaft 15, and its distal end is connected to a plate 17 via a rod 16, and the roller 18 is pivotally supported at approximately the middle portion in the longitudinal direction of the arm 14. There is. 14a is a biasing spring for the hydraulically actuated arm 14, and 17a is a pivot shaft for the plate body 17. The plate 17 is connected to a hydraulic rod 20 via a pin 19 protruding from the plate 17, and as the rod 20 advances and retreats, a switching arm 20' is rotated to switch the hydraulic valve P. ing.
Reference numeral 21 denotes a ball notch attached to the frame 2, and a hole 22 corresponding to the ball notch 21 is provided in the cam plate 1. 23 is an arm integrated with the cam plate 1, and an auto-lift operating rod 24 is attached to the rear end.
However, auto-return wires 25 are connected to the front ends via tension bombs 25a, respectively.
The operating lever 4 is adapted to automatically return from the oil pressure raising position to the neutral position by the tensile force of the ammunition 25a (so-called auto-return device).

26 is a connecting plate integrated with the hydraulic rod 20, and a pin 27 is attached to one end of the link 27 on the free end side of the connecting plate 26.
a, and the other end of the link 27 is connected to the pin 2.
8 and a long hole 29 to a sensor rod 30. 31 is a pivot point of the link 27. 32 is a float adjustment lever, and 33 is its fulcrum pin. 34 is an upper link, 35 is a lower link, and 36 is a hydraulic cylinder for raising and lowering the planting section connected to the upper link 34, and is connected to the hydraulic valve P via a pipe not shown in the figure. P, the hydraulic cylinder 36, etc. constitute an elevation control device M for the planting section N. A roller d intersecting the movement locus of the upper link 34 near the upper limit of its vertical movement stroke is rotatably provided on an arm f pivotally connected to the machine body via a support shaft e, The wire 25 is pulled by upward movement of the upper link 34 via a nut 25b screwed onto the tip of the wire 25.

37 is a float (center float) mounted below the planting part N so as to be movable up and down; 38 is a hydraulic pressure sensing lever; the lower end of the oil pressure sensing lever 38 is on the float 37 side, and the upper end is on the link holder 3 side.
9 through a fulcrum pin 40.
2, and the raising and lowering control of the planting part N is controlled by sensing vertical fluctuations based on changes in soil pressure from the rice field to the float 37 provided in the planting part N. The connected hydraulic pressure sensing lever 38, swing arm 41, etc., and the sensor rod 30 and switching arm 2 connected to the control device M side
This is done via an actuating mechanism S that is connected in a link-like manner at points such as 0'.

By the way, the sensor rod 30 is divided into parts so as to be expandable and retractable within a predetermined range, and each of the divided rod members is connected to the sensor rod 30 via a spring.
is biased in the direction of contraction. That is, the sensor rod 30 is connected to the bar 30 as shown in FIGS. 3 to 6.
It consists of a rod member 30' consisting of a fixed plate 30b extending integrally with a, and a movable plate connected to the fixed plate 30b so as to be slidable in the longitudinal direction within the range of the elongated hole 45 via guide pins 43 and 44. It is divided into a rod member 30'a,
A tension spring 48 is tensioned between a pin 46 protruding from the rod member 30' and a pin 47 protruding from the rod member 30'a, and during normal use, the spring 48 holds the rod member 30'a in place. The sensor rod 30 is held in a shortened state by being pulled toward the member 30a (see FIGS. 4 and 6). 48a is a spring hook portion.

FIG. 9 shows another embodiment, in which one side of a substantially V-shaped swinging arm 41' is attached to the upper end side of a hydraulic pressure sensing lever 38 whose lower end is directly pivotally connected to a float 37 with a fulcrum pin 49. The swing arm 41' is pivotally connected through a long hole 50 and a fulcrum pin 51, and the other side of the swing arm 41' is pivotally connected to a split-type sensor rod 30 configured in the same manner as described above. It has been stretched. A wire 53 connects the float adjustment lever 32, the oil pressure sensing lever 38', and the fulcrum pin 51.

In the above configuration, during planting work, when the float 37 moves up and down due to unevenness of the field surface, the hydraulic pressure sensing lever 38 moves up and down, and this causes the swing arm 41 to rotate around the fulcrum pin 40. Since the sensor rod 30 moves back and forth, the link 2
7. The hydraulic rod 20 and the switching arm 20' of the hydraulic valve P move in sequence, and the elevation control device M is automatically controlled.

Now, if the float 37 is on the verge of sinking in a soft field due to field conditions, the float adjustment lever 32 is operated to the floating side (to the right in FIG. 2). As a result, the fulcrum 31 of the link 27 moves to the left, and the link 27 rotates counterclockwise, so the switching arm 20' of the hydraulic valve P moves to the upward side, and the float 37 is set in a forward downward position. . In this case, since the switching arm 20' has moved to the rising side, the switching arm 20' will enter the rising range after the float rises a little more (sensing becomes faster).
Also, if the float 37 is floating too much in a hard field, by operating the float adjustment lever 32 to the sinking side (left side), the link fulcrum 31 and the link 27 will move in the opposite direction to the above, and the switching arm 20' will lower. The float 37 is moved to the front upward position. In the structure shown in FIG. 9, the attitude change of the float 37 is controlled by moving the oil pressure sensing lever 38' up and down with respect to the fulcrum pin 51 by operating the float adjustment lever 32, and changing the distance of the fulcrum pin 49 with respect to the fulcrum pin 51. I will do it.

By the way, if the float 37 suddenly rises (for example, when the planted part N is suddenly dropped on the road surface or when the float adjustment lever 32 is set to the floating side and the engine is stopped, the planted part N may descend and rise rapidly when touching the ground), excessive force is applied to the link-configured actuation mechanism S, causing the swing arm 4 to
1 or the sensor rod 30 may become bent or broken. In such cases, the spring 48
A rod member 30'a consisting of an extending and movable plate
There is no such inconvenience because the gas escapes within the range of the elongated hole 45.

Furthermore, the swinging arm 41 rotates each time the float 37 moves up and down due to unevenness in the rice field, etc., but the sensor rod 30 is constructed in a divided sliding type, and the hook portion 48a of the spring 48 is similar to the conventional one. Since the swing arm 41 is not locked to the pivot pin 42 of the sensor rod 30, there is no rotational friction that occurs between the spring hook portion 48a and the pin 42 at that part, and the link resistance is reduced, so that the hydraulic pressure sensing load is reduced. It can be made lighter and always provide stable oil pressure sensing.

Next, a case where hydraulic pressure control is performed manually will be described. The operating lever 4 is now in the neutral position shown by the solid line in FIG.
When the cam plate 1 rotates integrally with the operating lever 4 around the cam shaft 3, the roller 18 is placed on the top surface of the cam plate 1. The hydraulic operating arm 14 is moved upward using the support shaft 15 as a fulcrum, and as a result, the plate 17 rotates counterclockwise around the pivot shaft 17a, pushing the hydraulic rod 20 forward and opening the hydraulic valve. In order to move the switching arm 20' of P to the upward side, the hydraulic cylinder 36 is extended and the planting section N is elevated.

On the other hand, due to the rotation of the cam plate 1, the roller 7 moves relatively from a position near the lower top c of the cam plate 1 to the right upper part b, but between the top c and the right upper b, the cam shaft 3
The planting clutch arm 8 does not move and remains held at the clutch OFF position because it is formed into an arcuate surface centered at . When the hydraulic cylinder 36 is fully extended, the auto-return wire 25 is pulled through the upper link 34, roller d, and arm f, increasing the tensile force of the bullet 25a. The cam plate 1 and the operating lever 4 rotate in the opposite direction to the above, and the operating lever 4 is automatically returned to the neutral position.

Next, when the operating lever 4 is moved from the neutral position to the automatic/clutch OFF position that lowers the oil pressure, the roller 18 moves in the direction of pushing down the hydraulic operating arm 8, so the hydraulic valve P switches to the oil pressure lowering side, but the roller 7 Since the planting clutch arm 8 is still in pressure contact with the lower top c of the cam plate 1 and therefore does not move, the planting clutch 11 remains in the OFF state.

Furthermore, lower the hydraulic pressure on the operating lever 4 to engage the automatic clutch.
When tilted to the ON position, the cam plate 1 does not act on the roller 18 (the hydraulic operating arm 14 does not move), but the roller 7 fits into the valley a, and the planting clutch arm 13 moves counterclockwise. Due to the rotation, the planting clutch 11 is turned on.

In this way, both the hydraulic valve P and the planting clutch 11 are controlled simultaneously by operating one operating lever 4, but the planting clutch lever 13, which is normally held in the clutch OFF position, can be moved as needed. If you move the lever slightly in the ON direction, the lever 13
Since the bracket 6 integrated with the camshaft 3 rotates counterclockwise around the camshaft 3, the support shaft 9 of the planting clutch arm 8 moves rearward, and the roller 7 also moves along the cam plate 1. Since the wire 10 fixed to the tip of the attached clutch arm 8 loosens, the hydraulic valve P
Planting clutch 11 without being affected by
Can be switched to ON state.

The present invention can be applied not only to rice transplanters but also to paddy field working machines such as flooded direct sowing machines.

Effects of the invention As mentioned above, the present invention controls the vertical movement of a working machine installed on a traveling machine so that it can be raised and lowered by sensing vertical fluctuations based on changes in soil pressure from the field surface relative to a float installed on the working machine. In a paddy field working machine configured to operate a lift control device via an actuation mechanism that switches and operates the lifting control device, the actuation mechanism is connected to a hydraulic pressure sensing lever, a swing arm, etc. connected to the float side and a control device side. The sensor rod is composed of a sensor rod, a switching arm, etc., and the swing arm and the sensor rod are pivotally connected, and the center rod is divided into parts so as to be extendable and retractable within a predetermined range, and each of the divided rod members is connected to a spring. Since the sensor rod is biased in the shortening direction through the link, it is possible to eliminate the rotational friction that occurs between the spring hook part and its locking pin, and to minimize the link resistance.This makes it possible to reduce the hydraulic pressure sensing load and make it stable. In addition, it is possible to detect the hydraulic pressure in a controlled manner, and also to prevent deformation or damage to the link mechanism caused by the sudden rise of the float when the planting part lands.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the related structure of the hydraulic operating lever and the planting clutch lever, Figs.
Figures 6 to 6 are explanatory diagrams of the main parts, Figure 3 is a plan view of the abnormal state in which the spring is stretched, Figure 4 is a plan view of the normal operating state, and Figure 5 is a plan view of the rod member consisting of a movable plate. 6 is a side view in a normal operating state, FIGS. 7 and 8 are a plan view and an exploded perspective view of a conventional example, respectively, and FIG. 9 is a side view showing another embodiment. In the figure, M is the elevation control device, P is the hydraulic valve, S is the operating mechanism of the elevation control device, 20' is the switching arm of the hydraulic valve, 30 is the sensor rod, 30', 3
0'a is a rod member, 37 is a float, 38,3
8' is a hydraulic pressure sensing lever, 41 and 41' are swing arms, and 48 is a spring.

Claims (1)

[Scope of utility model registration request] An operating mechanism that switches and operates the lifting control device of a working machine installed on a traveling machine so that it can be raised and lowered by sensing vertical fluctuations based on changes in soil pressure from the field surface against a float installed on the working machine. In the paddy field work machine configured to operate through While pivotally connecting the swinging arm and the sensor rod,
A hydraulic control device for a paddy field working machine, characterized in that the sensor rod is divided into parts so as to be extendable and retractable within a predetermined range, and each of the divided rod members is biased in a direction in which the sensor rod is shortened via a spring.