JP2548123B2 - Tractor lifting control - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tractor lifting control device, and more particularly, to a tractor that enables a fine lifting operation and a normal lifting operation with a single operating lever. The present invention relates to a lifting control device.

[Prior Art] Conventionally, a fine lifting lever for slightly raising or lowering the ground work machine and a lifting lever for raising or lowering to a normal size are individually provided. In addition, in the official gazette, it is disclosed in Japanese Utility Model Publication No. 58-1304
There are 05 publications and Japanese Utility Model Publication No. 57-183822 publications.

[Problems to be Solved by the Invention] When lowering the working height of a ground work machine to a predetermined position, for example, first, the lifting lever is moved to the lower position, and
The ground work machine is controlled to a predetermined position by lowering it to a predetermined position and then slightly lowering it, for example, by operating a small elevating lever. It is difficult to operate the levers in the ascending direction or the descending direction without fail, and while carefully watching the position of the ground work machine, the two types of operating levers described above should be grasped and operated without error. In order to do so, sufficient skill is required.

Further, of the ones described in the above publication, the former merely discloses the means for setting the lowered position of the working machine, and there is a problem that this setting cannot be set to analog.

The latter discloses a configuration that enables a normal operation and a minute operation with a single operating lever.
There is a problem that the upper limit position and the lowering position cannot be set.

[Means for Solving the Problems] The present invention has been proposed in order to achieve the above-mentioned object, and a ground work machine connected to a rear portion of a tractor having a driver seat is provided with an upper limit position and a lower limit position. A height control device for a tractor that controls the height of the ground work machine to be freely changeable, and is a dial-adjustable analog setting device for setting the upper limit position and the lower limit position of the ground work machine, which are close to each other. For the upper limit position setter and the lower limit position setter, an analog lift sensor for detecting the current height position of the ground work machine, and those for the upper limit position setter and the lower limit position setter. A hydraulic lifting / lowering operation lever located nearer to the driver's seat and located in front of the operation lever, the operation lever being elastically biased to a neutral region in the normal state. A small operation area is provided outside the standing area, and a normal operation area is provided outside the small operation area. When the operation lever is placed in the minute operation area, the ground work machine moves up and down slightly and the operation lever is normally operated. When placed in the area, the ground work machine continues to reach the position determined by the upper limit setter or lower limit setter according to the difference between the value set by the upper limit setter or lower limit setter and the detected value of the lift sensor. A tractor lifting / lowering control device is characterized in that a control unit for controlling the lifting / lowering operation is provided.

[Operation] When the operation lever is rotated to slightly raise or lower in the minute operation range, the ground work machine is raised or lowered in minute increments, and the operation lever is further rotated. When trying to make a large ascent or descent in a large operating range (normal operating range), the ground work implement can continuously reach a position set by the ascending position setter or descending position setter with a large operation amount. Since it moves up or down, the above operation can be accurately performed for the turning operation of one operation lever, and the upper limit position setter and the lower limit position setter are dial adjustment type and the operation lever is used. Since they are spaced apart from each other, there is no risk of the arm touching these setting devices while gripping the operating lever.If you release your hand from the operating lever, the operating lever will return to the neutral range immediately. Ground work machine Stops.

[Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings. As shown in a side view in FIG. 1, the ground work implement 2 is connected to the tractor 1 by the work implement connection link mechanism 5 including the lower links 3 and 3 at the lower left and right and the top link 4 at the center upper part, and hydraulic lifting. The left and right lift arms 9 and 9 that move up and down with the movement of the lift piston 8 of the lift cylinder 7 of the mechanism 6 are connected to the lower links 3 and 3 via the left and right lift rods 10 and 10. The set value on the rising side or the set value on the falling side set by the operator,
A lift sensor S ₁ provided to detect the lift height of the ground work implement 2 (in the illustrated example, the rotation angle of the lift arm 9 is
The ON / OFF operation command of the ascending solenoid valve 11 or the descending solenoid valve 12 is configured by a microcomputer or the like so that the lift detection values (detected by the rotary potentiometer) match. It is configured to be amplified and output from the control unit 13 via the ascending drive unit 14 or the descending drive unit 15. The setting operation for each of the ascending side setting value and the descending side setting value is illustrated in FIG. 5 by using the dial-adjustable ascending position setting device IU and descending position setting device ID, which are configured by something like a volume. As described above, it is provided near the driver's seat 16 of the tractor 1 and at a suitable distance behind the operation lever 18 so as not to hit when the operation lever 18 is rotated back and forth. A side view is shown in FIG. Like, axis
A cam 19 is attached to an operation lever 18 which is rotatably provided to 17, and a micro-raising switch SU ₁ , a micro-descending switch SD ₁ , a raising switch SU ₂ and a descending switch SD ₂ using a micro switch or the like are respectively attached. , Attached to the machine frame, springs 20 and 2
The operation lever 18, which is normally held neutral by 1, 22, and 23, is moved in the direction of the arrow U in the minute operation area of the first operation area.
When rotating only RU, the cam 19 turns on the micro-raising switch SU ₁ and when operating only the micro-operating area RD in the direction of arrow D, the micro-lowering switch SD ₁ turns on, and the micro operating area RU When operating in the direction of the arrow U in a large operation range (normal operation area) which is the second operation area beyond, the ascending switch SU ₂ is turned on in addition to the minute ascending switch SU ₁ , and the minute operating range RD is while when operating in the normal operation range in the arrow D direction beyond the addition of the micro-lowering switch SD _1, which is configured to down switch SD ₂ is also turned on, the micro raising switch SU ₁ continues to turn on, small The setting value is stepwise for the amount α (that is, like α, 2α, 3α ...)
As long as the value increases and the minute descent switch SD ₁ continues to be turned on, the setting value is stepwise for a minute amount (-β) (that is, -β,
-2β rise, and the controller 13 acts to increase-3.beta ... As), other micro-raising switch SU _1, while raising switch SU ₂ also continue on, which are set at the raised position setter IU It becomes the set value that the minute amount α is sequentially added to the position set value, and the descent position set value set by the descent position setter ID while the minute descent switch SD ₁ and the descent switch SD ₂ continue to be turned on. When the control unit 13 operates so that the minute amount (-β) is sequentially added to the set value and the operation lever 18 is operated to the up side, the lift detection value is added to the above set value on the up side. , And when operated to the descending side, the control unit 13 commands the ascending drive unit 14 or the descending drive unit 15 to output so that the lift detection value matches the set value on the descending side. This control operation is shown in the flow chart of FIG.

Therefore, for example, while the operation lever 18 is operated in the direction of the arrow U and placed in the minute operation area RU, the lift arm 9
Will continue to rise in small steps, and in this state, if the operating lever 18 is returned to the neutral position N in FIG. 4, the lift arm 9 will stop at that position, and then the operating range RU When a large operation is made in the direction of the arrow U beyond the point, the set value is changed to the ascended position set value set by the ascended position setter IU, and the lift arm 9 quickly ascends. When it is held as it is, the lift arm 9 continues to move up to the minute again.

Then, in this way, for example, the lift arm 9 is moved to the raised position.
Even if is held, when the operating lever 18 is operated in the direction of the arrow D and placed in the minute operation area RD, the set value is a minute amount (-
beta) addressed, the lift arm 9 is addressed micro supposed to decrease sequentially, it the lift arm 9 is addressed micro continue falling, will continue to descend, when operating in a position lowering switch SD ₂ is turned on The lift arm 9 quickly descends to a height corresponding to the set value of the lowered position.

Effect of the Invention] The tractor lifting control device according to the present invention is configured as described above, and sets a small amount while the hydraulic lifting operation lever is rotated to operate in the minute operation range. Since the value is set, the hydraulic lifting mechanism will move up or down with a minute amount, and while the operating lever is further rotated to operate in the normal operating range, the dial adjustment type analog upper limit position setting The hydraulic elevating mechanism is moved up or down greatly according to the difference between the set value set by the device or the lower limit position setter and the detected value.

In this way, the height position of the ground work implement can be easily fine-tuned by a simple operation of moving one operating lever in the front-back direction, and a lever operation that moves it slightly from the neutral range, and a lever that moves greatly from the neutral range. The height position of the ground work machine can be quickly adjusted by an operation, and the lifting and lowering of the ground work machine can be easily operated with a small or large amount by an easy operation.

Furthermore, when turning at the edge using the operation lever, the operator sitting in the driver's seat operates the operation lever without looking back and operates the ground work implement connected to the rear part of the tractor to the upper limit position setting device. Or, it will be possible to move up and down accurately and quickly to the height position set by the lower limit position setting device, and other operations such as handle operation performed during turning can be performed with sufficient margin and necessary for operation during turning. The skill level is small. For example, when turning around a ridge, the operator swivels the operating lever to the upside while watching the direction of travel to quickly lift the work implement to the height set by the upper limit position setting device, and after turning. Can rapidly lower the work implement to the set tillage depth by tilting the operating lever to the lower side. Therefore, the operation at the time of turning can be performed quickly, easily and safely, and there is no fluctuation in the working depth before and after the turning.

Further, the operation lever is arranged in front of the dial-adjustable upper limit position setter and lower limit position setter, and the mutually related ascending position setter and descending position setter are provided close to each other. Since it is possible to adjust the upper and lower limit positions of the working machine quickly, there is no risk that the two dial-adjustable setting devices will be accidentally turned when operating the operating lever back and forth. Operability is significantly improved.

Further, since the operation lever is normally urged to be in the neutral range, it is not necessary to return the operation lever from the target position to the neutral range again, and the operation is simplified and the handling is easy.

[Brief description of drawings]

1 is a side view of a tractor, FIG. 2 is a control circuit diagram, FIG. 3 is a flow chart, and FIG.
FIG. 4 is a side view of the main part, and FIG. 5 is a perspective view of the main part of FIG. Explanation of code 1 …… Tractor 2 …… Ground work machine 5 …… Work machine connecting link mechanism 6 …… Hydraulic lifting mechanism 13 …… Control unit 18 …… Operating lever S ₁ …… Lift sensor IU …… Raising position setter ID …… Descent position setting device

Claims (1)

(57) [Claims] 1. An elevation control device for a tractor, which vertically controls a ground work machine connected to a rear portion of a tractor having a driver's seat between an upper limit position and a lower limit position. A dial-adjustable analog setting device for setting the upper limit position and the lower limit position of the ground work machine, the upper limit position setter and the lower limit position setter provided in close proximity to each other, and the current ground work machine An analog lift sensor for detecting the height position, and one hydraulic lifting / lowering lever provided near the driver's seat and located in front of the upper limit position setter and the lower limit position setter. The operating lever is elastically urged to be a neutral region in a normal state, a fine operating region is provided outside the neutral region of the operating lever, and a normal operating region is provided outside the fine operating region. The operation When the bar is placed in the minute operation area, the ground work implement moves up and down slightly, and when the operating lever is placed in the normal operation area, the difference between the value set by the upper limit position setter or the lower limit position setter and the detected value of the lift sensor is set. The tractor lifting control device is provided with a control unit that controls the ground work implement to continuously move up and down to a position determined by the upper limit position setter or the lower limit position setter according to the above.