JPH0455456Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Industrial Application Field] The present invention relates to a lifting control device for a working part of a rice field working machine such as a rice transplanter, a fertilizer, a seeding machine, etc. [Problems to be solved by the prior art and the invention] In general, in this type of paddy field working machine, the attitude of the machine body with respect to the rice field is not changed due to changes in the unevenness of the tiller on which the running wheels run. By automatically switching the elevation control valve based on the detection of unevenness of the tiller, the running wheels are moved up and down relative to the machine body, thereby automatically controlling the elevation. By the way, when this automatic elevation control is performed when the aircraft is moving backwards, the front side of the aircraft is tilted low due to the reaction force during the backward movement, and the sensing float is pushed up relative to the aircraft body. When the same situation is detected as if the plowing platform is getting deeper, the elevation control valve will be switched to raise the aircraft, and as a result, the aircraft will become higher and higher, tilting forward, and the operating handle will be turned off. The sides of the vehicle will rise, making it virtually impossible to drive backwards. Therefore, when going backwards, it is conceivable to configure the aircraft to be restrained from rising by activating a restraining means linked to the backward operation, but in this case, when attempting to resume work travel after completing backward travel, Since the restraining means remains in the aircraft ascent restraining state, the operating device means for restricting the automatic switching of the elevation control valve is first operated to the fixed position where it restricts the aircraft ascent, and then to the automatic switching position. As a result, the operation becomes troublesome and complicated, and erroneous operations often occur, resulting in a significant decrease in work efficiency. It becomes a problem. [Means for solving the problem] In view of the above-mentioned circumstances, the present invention was devised for the purpose of providing a lifting and lowering control device for the working part of a paddy field working machine that can eliminate these drawbacks. In a paddy field working machine in which the vertical movement of the machine body is performed by automatic switching of a vertical movement control valve linked to the vertical movement of a sensing float, there is provided an operating tool means for restricting automatic switching of the vertical movement control valve. The gear clutch is connected to a transmission clutch switching means that switches the aircraft forward and backward.
Further, a restraining means is provided for restraining the elevation control valve from switching to the aircraft raising state when the transmission clutch switching means is switched to the reverse traveling state, and the restraining means includes an operating tool means when the shift clutch switching means is switched to the reverse traveling state. The present invention is characterized in that a holding release mechanism is provided for displacing the operating tool means to a position where switching of the valve to the aircraft body up state is restricted by releasing the holding of the operating position of the operating tool means. The present invention uses this invention to automatically check the switching of the valve to the upward side of the aircraft when moving in reverse, allowing for stable backward movement. is arranged so that it is displaced to a fixed position. [Example] Next, an example of the present invention will be described based on the drawings. In the drawing, 1 is a walking type rice transplanter, and the rice transplanter 1 is equipped with an engine 2 in the front.
A seedling platform 3 with a lower front and rear height is provided at the rear, and unit planting seedlings are scraped from the seedling platform 3 and planted on the rice field by the planting operation of a planting claw 4 timed with the movement of the aircraft. Everything is the same as before. Reference numeral 5 denotes a running wheel, and the running wheel 5 is supported by a wheel 5a at the tip of a second chain case 6 constituting a bent chain case. The proximal end portion is pivotally supported by the distal end portion of the first chain case 7 so as to be swingable (flexible). The first chain case 7 is pivotably supported on the upper part of the transmission case 8 about a support shaft 7a as a fulcrum. The running wheels 5 are adapted to travel and rotate as a result of the driving force from the engine being transmitted through the transmission case 8, the first chain case 7, and the second chain case 6. Further, it is connected via a link 14a to a telescopic cylinder 14 for lifting and lowering wheels, which will be described later, and a fulcrum 23a accompanying its telescopic operation.
Due to the swinging of the swinging arm 23 using the swinging arm 23 as a fulcrum, both the chain cases 6 and 7 undergo a bent swinging deformation, thereby causing the traveling wheels 5 to follow the trajectory shown in FIG. It is designed to move up and down. On the other hand, 9 is a sensing float (center float)
The sensing float 9 has a support shaft 9a at the rear.
The front portion is supported on the body side by a bending link mechanism 10. Furthermore, the lower end of a link rod 12 is connected to the sensing float 9, and the upper end of this link rod 12 is constantly urged downward by the ammunition X to the lower end of the operating link 15. Further, the operating link 15 is provided with a long hole-shaped flexible portion 15a, and a pin 12b that loosely fits through the flexible portion 15a is inserted into the valve shaft 13a of the elevation control valve 13.
It protrudes from an actuating plate 16 that is integrally provided with the actuating plate 16.
When the sensing float 9 swings up and down due to changes in ground pressure from the field surface due to changes in the unevenness of the tiller, the operating link 15 moves up and down together with the link rod 12, causing the operating plate 16 to rise. (When the plowing platform becomes deep and the machine sinks), it is rotated in the direction of arrow C, and when descending (the machine rises), it is rotated in the opposite direction. When the machine rotates in the direction of arrow C, the machine moves upward, and when it rotates in the opposite direction of arrow C, the machine moves downward.This reduces the telescopic cylinder 14 and lowers the traveling wheels 5 relative to the machine. It is now possible to perform vertical movement control. Further, on the actuating plate 16, connecting links 17 and 18 are provided on the upper and lower sides with the valve shaft 13a sandwiched therebetween, and pins 17b and 18 are connected to elongated flexible portions 17a and 18a.
8b. The upper second connecting link 17 is interlocked with the tip of a second hydraulic wire 37, which will be described later, and the lower first connecting link 18 is connected with the tip of a first hydraulic wire 36, which will also be described later. Furthermore, between the pin 18b and the outer receiver 37a side of the second hydraulic wire 37 of the bracket 1a (the bracket 1a is integrally fixed to the main body side) where the outer receivers 36a, 37a of both wires 36, 37 are provided. , actuation plate 1
A bullet Z is interposed to urge the ball 6 in the opposite direction C. On the other hand, 24 is a gear shift clutch lever, and by operating the gear shift clutch lever 24 to its corresponding shift position (in the embodiment, forward two-speed F1, F2, neutral, and reverse R positions), the connecting rod is 25
The shifter shaft 26, which is connected to the connecting rod 25 via the link arm 26a, is moved in and out of the transmission case 8, thereby causing the shift clutch mechanism (not shown) to move as described above. This gear shift clutch lever 24 is provided with a protruding pin 24a, and this pin 24a is connected to the driving handle 2 by a pin shaft 27b.
It is opened in the movable plate 27 which is pivotably mounted on the zero side, and the reverse side end thereof passes through an arc-shaped elongated hole 27a which is notched in the shape of a substantially circular arc. When switching between the neutral N position and the forward F1 and F2 positions as described above, the pin 24a moves within the range of the elongated hole 27a,
The movable plate 27 does not move, but remains at the neutral position N.
When the pin 24a contacts the end of the elongated hole 27a and swings the movable body 27 in the direction of arrow A in FIG. The connecting rod 28 to which the parts are connected is pulled and moved in the direction of arrow B. still,
The fulcrum 27b of the movable plate 27 is eccentric to the arcuate fulcrum of the elongated hole 27a, so that when the transmission clutch lever 24 is operated to the reverse position, the pin 24a is inserted into the notch at the end of the elongated hole. 27b
When the transmission clutch lever 24 is operated from the reverse R to the neutral N position, the movable plate 27 is swung back to its original position by pressing the engagement portion. Note that 24b is a guide for the speed change clutch lever 24. On the other hand, 29 is an operation case provided at the center of the upper part of the left and right driving handles 20, and the operation case 29
A support shaft 29a provided between the left and right side plates of the left side has a lever on the left side that allows you to switch between "enter", "off", and "fix" by linear operation from the hand side to the near side along the lever guide 29a. The boss portion 30a of the traveling clutch lever 30, which can be operated in a straight line from the hand side to the near side along the lever guide 29b, is also located on the right side and can be moved into, off, fixed, or up by linear operation from the hand side to the near side along the lever guide 29b. A boss portion 31a of a planting clutch lever 31, which can be used to switch the lever between the two positions, is rotatably connected. Further, first cam arms 32 and 33 are pivotally connected to the outside of these boss portions 30a and 31a, respectively. Further, both levers 30 and 31 have connecting arms 30b,
31b, as well as first cam arms 32, 3 as described below.
3. Lever pins 30c and 31c related to the second cam arms 38 and 39 are provided, respectively. One end of a traveling clutch wire 34 is connected to the distal end of the traveling side connecting arm 30b, and a planting clutch wire 34 is connected to the distal end of the planting side connecting arm 31b.
The traveling clutch wire 34 is pulled by operating the traveling clutch lever 30 from the "off" position on the lever guide 29a to the "on" position (the position operated most forward). As a result, the traveling clutch (not shown) is set to be in the ON state, and on the other hand, the planting clutch lever 31 can be similarly operated from the "OFF" position to the "ENTER" position on the lever guide 29b. This loosens the planting clutch wire 35, thereby setting a planting clutch (not shown) to be in the ON state. Further, a pin 32c provided at one end of the first cam arm 32 on the traveling side is attached to a bullet Y (the relationship between the biasing forces of the bullet Y and the bullets X and Z described above is X>Z). , and set so that X<Z+Y) is interlocked and connected to the base end of the first hydraulic wire 36 via an interposed buffer mechanism 19, and Pin 33 provided at one end
A base end portion of a second hydraulic wire 37 is interlocked and connected to c, and furthermore, cam surfaces 32a and 33a corresponding to lever pins 30c and 31c are connected to one end portion of the first cam arms 32 and 33, and cam surfaces 32a and 33a on the traveling side first cam arm 3
A cam surface 32d corresponding to a pin 42c of a third cam arm 42, which will be described later, is formed on each of the first cam arms 32 and 33, and a pin 32b,
33b is provided protrudingly. Further, second cam arms 38 and 39 are provided on the left and right side plates of the operation case 29, respectively, and the first cam arms 32 and
33, and is pivotally connected by pin shafts 38a and 39a so as to be freely swingable. This second cam arm 3
8 and 39 are both first fired by the bullet 40.
As shown in Fig. 4, the second cam arm 38 on the traveling side is biased in the direction of arrow D when the traveling clutch lever 30 is operated to the "off" position and the "fixed" position. , cam surfaces 38b and 38c on which the lever pin 30c abuts and locks, and a cam surface 38 corresponding to a pin 42b of a third cam arm 42, which will be described later.
d, and a cam surface 38e that locks the pin 32b beyond the corner portion 38f, as will be described later. Also, the second cam arm 39 on the planting side
The cam surfaces 39b, 39c, 39d, and pin 33b that the lever pin 31c abuts and locks when the planting clutch lever 31 is operated to the "cut" position, "fixed" position, and "up" position, respectively, are described later. A cam surface 39e is formed which is locked when it extends beyond the corner portion 39f. To operate and hold each lever 30, 31 in its corresponding position, the lever pins 30c, 31c press the cam surface and swing the second cam arms 38, 39 against the elastic force 40, so that the lever pins 30c, 31c press the cam surface and swing the second cam arms 38, 39 between the cam surfaces. It is accomplished by moving in a state of crossing mountains. In addition, both levers 30, 3
1, when it is operated to the "enter" position, it is held in that position by a fulcrum crossing action.
Furthermore, the first cam arms 32 and 33 are connected to the lever 3.
When the lever pins 30c and 31 are operated to the "off" position, the lever pins 30c and 31c come into contact with the cam surfaces 32a and 33a, and by operating the levers toward the front side of the "off" position, the lever pins 30c and 31c are moved. It is designed to oscillate and displace integrally. Moreover, by this lever switching operation, the pins 32b, 33b of the first cam arm are moved to the lever 30, as will be described later.
31 is in the "cut" position, it is located more forward than the corner parts 38f and 39f, and is in the "fixed" position.
When it is in the position, as described above, the corner portions 38f, 39f are moved in time with the swinging of the second cam arms 38, 39 in the anti-D direction against the bullet 40 as the lever is operated to the position. The first cam arms 32, 33 are held in a locked position by contacting and engaging the cam surfaces 38e, 39e. The first cam arms 32 and 33, which are held locked in this way, are connected to the second cam arms 3
The lock cannot be released unless the arms 8 and 39 are forcibly swung in the direction of the reverse arrow D against the ammunition 40. Note that 41 is a stopper for the cam arms 32, 33, and 39. When both the traveling clutch lever 30 and the planting clutch lever 31 are operated between the "off" and "on" positions, the lever pins 30c, 31c are moved to the second cam arms 38, 39 as shown in FIG. The pins 18b and 17b on both the first connecting link 18 and second connecting link 17 sides are brought into contact with the cam surfaces 38b and 39b and then moved away from the cam surfaces 38b and 39b. , 17a, and is in an automatic control state. In this state, when the sensing float 9 moves up and down with respect to the machine body due to the unevenness of the tiller, the actuating plate 16 swings by the vertically moving pin 12b, the machine body sinks, and the actuating plate 16 moves up and down. When it swings in direction C in Figure 5, the lift control valve 13
When the machine lifts up and the actuating plate 16 swings in the counter-C direction, the lift control valve 13 is switched to the machine lower side, and the machine maintains a substantially constant attitude with respect to the rice field. It is now possible to set the system to an "automatic control" state. On the other hand, when the planting clutch lever 31 is operated to the "fixed" position, the planting clutch lever 31
In this case, the lever pin 31c comes into contact with the cam surface 39c of the second cam arm 39 and is held in this position, but the movement of the lever pin 31c at this time also causes the first cam arm 33 to swing in the same direction. The second hydraulic wire 37 is pulled by approximately the amount of play between the pin 17b and the front end of the flexible portion 17a, thereby rotating the actuating plate 16 in the opposite direction of arrow C, that is, moving the valve 13 toward the lowering side of the fuselage. This is designed to discourage switching. Therefore, when the traveling clutch lever 30 is in the "on" or "off" position and the planting clutch lever 31 is operated to the "fixed" position, only the lifting operation of the machine body is automatically performed and the lowering operation is fixed. The state is "raised automatically lowered fixed". Furthermore, when the planting clutch lever 31 is operated beyond the above-mentioned "fixed" position to the "raised" position, the planting clutch lever 31 is moved to the lever pin 3.
1c is brought into contact with and locked to the cam surface 39d of the second cam arm 39, and is held in this position.
is also oscillated in the same direction, thereby pulling the second hydraulic wire 37 and moving the second connecting link 17 rearward, forcibly rotating the actuating plate 16 in the direction of arrow C to open the valve 13. When the machine is switched to the up side, and the traveling clutch lever 30 is in the "on" and "off" positions and the planting clutch lever 31 is operated to the "up" position,
The aircraft enters the "manual lift" state, where the aircraft rises by manual lever operation. On the other hand, when the travel clutch lever 30 is operated from the "off" position to the "fixed" position, the travel clutch lever 30 is moved so that the lever pin 30c is connected to the second cam arm 3.
The lever pin 30c abuts and locks the first cam arm 38c on the cam surface 38c of the first cam arm 30, and is held in this position.Due to the lever movement at this time, the lever pin 30c displaces the first cam arm 32 in the direction of the arrow E. As a result, the first hydraulic wire 36
is pulled so as to compress the ammunition Y, and the pin 18b comes into contact with the front end of the flexible portion 18a, causing the actuating plate 16 to rotate in the direction of arrow C, that is, the valve 13 moves toward the body-raising side. Switching to is restricted. Therefore, when the planting clutch lever 31 is in the "on" or "off" position and the traveling clutch lever 30 is operated to the "fixed" position, only the lowering operation of the machine body is automatically performed and the raising side is fixed. If both levers 30 and 31 are operated to the "fixed" position, rotation of the operating plate 16 to either side is restrained, and the aircraft In this way, the levers 30 and 31 are in a "fixed" state with no vertical movement.
Control switching is now possible. In this manner, an operating means that can be operated to limit automatic switching of the elevation control valve 13 in this embodiment is constructed. Furthermore, when the driving clutch lever 30 is operated to the "fixed" position while the planting clutch lever 31 is operated to the "up" position as described above,
The planting clutch lever 31 is adapted to be automatically displaced to the "fixed" position. In other words, when the planting clutch lever 31 is operated to the "up" position,
As mentioned above, the lever pin 31c is connected to the second cam arm 3.
The pin 33b of the first connecting link 33 is in an unlocked state as it is separated from the cam surface 39e of the second cam arm, and the first connecting link 33 is held in contact with the cam surface 39d of the second cam arm. The side pin 18b is in contact with the front end of the flexible portion 18a. In this state, the traveling clutch lever 30 is operated from the "off" position to the "fixed" position, and the first hydraulic wire 36 is pulled rearward while compressing the ammunition Y.
6 forcibly rotated in the opposite direction of arrow C.
3 to the neutral state, the second hydraulic wire 37
is pulled forward while receiving a buffering effect from the bomb Y, and this forward pulling force causes the first link arm 33 on the planting side to move the lever pin 31c in a direction opposite to the arrow E.
As a result, the lever pin 31c swings the second cam arm 39 against the bullet 40 and crosses over the mountain between the cam surfaces 39d and 39c, and the pin 33b touches the cam surface 39e. The planting clutch lever 31 is automatically displaced to the abutting position, that is, the "fixed" position. Further, the third cam arm 42 is swingably supported on the side plate of the operation case 29 via a support shaft 42a, and one end of the third cam arm 42 is provided with the aforementioned shift clutch lever 24. arrow B when moving backwards.
The upper end of the connecting rod 28 that moves in the direction is the pin 42b.
is further connected by a third cam arm 4.
2, on the traveling clutch lever 30 side, the cam pin 42c is related to the cam surface 32d formed on the one end 32a side of the first cam arm 32, and the cam surface 38d is formed on the upper end of the second cam arm 38. cam pins 42d are formed respectively. Then, when the third cam arm 42 swings in the same direction due to the movement of the connecting rod 28 in the direction of arrow B due to the operation of the transmission clutch lever 24 to the reverse position, the first cam arm 32 moves from the cam surface of the cam pin 42c. 32d, the traveling clutch lever 30 swings in the same manner as when it is operated to the "fixed" position as described above, thereby pulling the first hydraulic wire 36 and moving the valve 13 to the fuselage-raising side. While the second cam arm 38 is in a state where the switching to the cam pin 4 is checked, the second cam arm 38 is
2d, the lever pin 30c is oscillated in the opposite direction of arrow D against the ammunition 40, and the lever pin 30c is brought into contact with the cam surface 38c (cutting).
(hold position) is released and the traveling clutch lever 3
The holding release mechanism of the present invention is configured to automatically displace to the "fixed" position of 0. This lever automatic displacement force is achieved by, for example, a belt tension on the traveling clutch side or a tension pulley lowering its own weight. Then, when the planting clutch lever 31 is operated to the "raise" position and the second hydraulic wire 37 is pulled in this switching check state on the aircraft raising side, the first hydraulic wire 36 is stretched due to the compression of the ammunition Y, and the actuating plate is 16 rotates in the direction of arrow C to open the lift control valve 13.
is switched to the body-raising side, and a checking means is configured to check the valve switching to the body-raising side when the airplane moves backward, and this checking means further controls the pressing direction of the cam pin 42d of the cam surface 38d during the backward movement. is set to move in the direction of the connecting rod 28 beyond the fulcrum of the support shaft 42a, so that the shift clutch lever 24 can be positioned and maintained in the reverse position. In the embodiment of the present invention constructed as described above, when the traveling clutch lever 30 and the planting clutch lever 31 are operated to the "on" and "off" positions, the elevation control valve 13 is operated so that the actuating plate 16 moves in both directions. It is in an automatic control state that allows it to swing. Therefore, by the vertical movement of the sensing float 9 that senses the unevenness of the tiller, the elevation control valve 13 is switched to the raising side or the lowering side of the machine body, and automatic control of raising and lowering the machine body is achieved. As a result, the posture of the machine relative to the rice field can be maintained substantially constant regardless of the unevenness of the tiller. In this state of automatic control of the aircraft attitude, the transmission clutch lever 24 is operated to the reverse R position in order to travel in reverse. Then, the connecting rod 28 moves in the B direction, the third cam arm 42 swings in the direction, and the first cam arm 32 and the second cam arm 38 on the running side are forced to swing in the E direction and the opposite D direction. let As the first cam arm 32 swings in the E direction, the first hydraulic wire 36
is pulled rearward and restricts the swinging of the actuating plate 16 in the direction of arrow C, thereby restraining the elevation control valve 13 from switching to the aircraft lifting side. As a result, when the aircraft is moving backward, even if both levers 30 and 31 are set to the temporary aircraft's automatic elevating control state, the "lowering automatic raising and lowering fixing" is performed by the above-mentioned traction function.
The situation is the same as in the case of , and the aircraft will not rise due to the sensing float 9 sensing the rise.
Therefore, even if the aircraft body assumes a posture in which the front side is lowered due to the backward reaction force, the aircraft body will not rise at all, and stable backward travel will be possible. During this backward movement, the second cam arm 38 on the traveling side is swung in the direction of the reverse arrow D by the third cam arm 42, which has swung in the direction of the arrow B, as described above. As a result, the traveling clutch lever 30 is
The lever pin 30c is connected to the cam surface 32 of the first cam arm 32.
The holding at the "cut" position by c is released and becomes a free state, and it is automatically displaced toward the "fixed" position. Then, when the backward movement is completed, the displacement clutch lever 24 is operated from the reverse movement position R to the neutral position N side to start the work movement again, and the third cam arm 4
2 to its original position and the second cam arm 38
When the traveling clutch lever 30 is swung in the direction of arrow D by the biasing force of the ammunition 40, the lever pin 30c abuts and locks the cam surface 32c of the first cam arm 32, and the traveling clutch lever 30 is in this "fixed" position. will be retained. Therefore, in order to restart the planting work, the travel clutch lever 30, which is in the "fixed" position, must be moved to at least the "off" position to allow the actuating plate 16 to swing freely in both directions. "Automatic control"
This automatically releases the restraint on raising the aircraft when it is in the reverse state. As a result, as in the past, the travel clutch lever 30 is first operated to the "fixed" position, which is the position that restricts the valve switching to the aircraft raised state, and then manually operated to the "off" position again to check the clutch lever. There is no need for the trouble of canceling the release, and as a result, work efficiency can be significantly improved, and erroneous operations can be prevented, resulting in improved operability. Incidentally, in order to make the explanation easier to understand, the following table shows the lifting and lowering control state of the machine body by lever operation of the travel clutch lever 30 and the planting clutch lever 31 that constitute the valve switching mechanism adopted in this embodiment.

[Table] [Operations and Effects] In summary, the present invention is constructed as described above, so that the restraining device operates the elevation control valve in conjunction with switching the transmission clutch switching means to the reverse state in order to move the aircraft in reverse. This will prevent the aircraft from switching to the up side, and therefore, even if the forward side of the aircraft is lowered due to backward reaction force and the aircraft is detected to be on the up side, the ascent of the aircraft will be restricted based on this. You can move backwards in a stable position. Furthermore, when the vehicle is in the reverse state, the operating tool means is automatically released from being held at the operating position by a holding release mechanism provided in the check means, and is displaced to a position that restricts valve switching to the aircraft raised state. Therefore, when the transmission clutch switching means is operated from the reverse position to the traveling position in order to resume working travel, the operating tool means located at this limit position is operated to the automatic control position. Therefore, the restraint on switching to the body-up state is reliably released, and the restraint will not remain unreleased as in the past. As a result, there is no need to bother with releasing the check each time, and it is possible to significantly improve work efficiency, and it is also possible to prevent erroneous operations and improve operability.

[Brief explanation of drawings]

The drawings show an embodiment of the elevating and lowering control device for the working part of the rice paddy work machine according to the present invention, in which Fig. 1 is an overall side view of the walking rice transplanter with the bonnet removed, and Fig. 2 is an overall side view of the walking rice transplanter with the bonnet removed. 3 is a side view of the elevation control cylinder section, FIG. 4 is a plan view of the elevation control cylinder section, FIG. 5 is a side view of the elevation control mechanism, FIG. 6 is an explanatory diagram of the operation of the transmission clutch lever, and FIG. The figure is a connection diagram of the transmission clutch lever, Figures 8 J and K are a front view and sectional view of the first cam arm on the traveling side, and Figures 9 J and K are a front view, sectional view, and sectional view of the second cam arm on the traveling side. Figure 10 J, K
are a front view and a sectional view of the first cam arm on the planting side, and the 11th cam arm.
Figures J and K are a front view and sectional view of the second cam arm, Figure 12 J and K are a front view and sectional view of the third cam arm, Figure 13 is a front view of the operating handle, and Figure 14. is a side view with a part of the front cut away, FIG. 15 is a plan sectional view of the main part of the front, and FIG. 16 is a bottom sectional view of the main part of the front.
Figure 17 is a rear view of the rice transplanter, Figure 18 is an explanatory diagram showing the movement of the cam arm when the traveling clutch lever is operated, and Figure 19 is a diagram showing the movement of the cam arm when switching to the reverse mode. FIG. 20 is an explanatory diagram showing the movement of the cam arm when the planting clutch lever is operated, and FIG. 21 is an explanatory diagram showing the operation positions of the traveling clutch lever and the planting clutch lever. . In the figure, 1 is a traveling aircraft body, 5 is a traveling wheel, 9 is a sensing float, 13 is a lift control valve, 16 is an operating plate, 17 and 18 are connecting links, 24 is a gear shift clutch lever, 30 is a traveling clutch lever, and 31 is a Planting clutch lever, 32, 33 are first cam arms,
36 and 37 are hydraulic wires, 38 and 39 are first cam arms, and 42 is a third cam arm.

Claims (1)

[Scope of utility model registration request] In a paddy field working machine in which the vertical movement of the machine body is performed by automatic switching of a vertical movement control valve linked to the vertical movement of a sensing float, the operating tool means for restricting the automatic switching of the vertical movement control valve includes: , a check means is provided which is connected to a speed change clutch switching means for switching the aircraft forward and backward, and which restrains the elevation control valve from switching to the aircraft raised state when the speed change clutch switching means is switched to the reverse state; The check means is provided with a holding release mechanism that releases the operating position of the operating tool means upon switching to the reverse state and displaces the operating tool means to a position that limits switching of the valve to the aircraft raised state. A lifting control device for a working part of a paddy field working machine, characterized in that: