JPH1054056A - Lifting-lowering controller for working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce repeated operation at the determined height place of a boom simply and surely, and to make it unnecessary to exercise care for preventing an interference with others at the time of the lifting operation of the boom. SOLUTION: An automatic stop means automatically stopping the lifting- lowering operation of a boom 18 for a front loader 6 at the two places of a set height place on the high side and a set height place on the lower side and an upper-limit stop means setting a set maximum upper-limit place as an upper limit, from which the boom 18 is not lifted more than that, are mounted on the lifting-lowering controller. When the set maximum upper-limit place by the upper-limit stop means is lower than the set height place on the high side by the automatic stop means, a linking control means, by which the upper-limit stop means preferentially function, is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lifting / lowering control device for a working machine such as a tractor provided with a front loader device and a wheel loader.

[0002]

2. Description of the Related Art A working machine in which a working device having a front end of a boom capable of swinging up and down with respect to a machine body and a working tool capable of swinging up and down with respect to the boom is connected to a traveling machine body includes: The one disclosed in Japanese Utility Model Laid-Open No. 4-110406 is known, in which the work implement is constituted by a bucket.

[0003]

In the front loader device provided with the above-mentioned bucket, the work of mainly scooping earth and sand and gravel is carried out, for example, by loading earth and sand on the ground onto a carrier bed of a transport vehicle. In such work, the bucket is moved up and down between a low scooping position near the ground to save the earth and sand, and a nearly dumped position where the height is almost fixed to lower the earth and sand on the carrier of the transport vehicle, or in a warehouse. Raising and lowering the bucket over a relatively high range of scooping positions and a nearly fixed low dump position in order to load the fertilizer deposited on the truck onto a truck bed lower than the warehouse ground become.

That is, the height is often constant at the dump position on the higher or lower side of the ascending and descending movement of the bucket, but what is required to repeat the operation to the fixed position by the conventional manual operation is It was necessary to adjust the boom to a certain height, and the operation was troublesome and troublesome, and it was also difficult for an unskilled pilot to repeat the operation to the certain height.
In addition, when performing work in a house or the like, it is necessary to always pay attention to the operation of raising the boom in order to avoid interference between the front loader device and the ceiling.

SUMMARY OF THE INVENTION It is an object of the present invention to make it easy and reliable to repeatedly operate a boom at a predetermined height position and to prevent interference with other objects when the boom is lifted. The purpose is to eliminate the need.

[0006]

[Means for Solving the Problems]

[Configuration] A first aspect of the present invention is a lifting and lowering control device for a working machine which is connected to a machine body such that a boom having a working tool connected to a tip thereof can swing up and down, and detects a height of the boom with respect to a traveling machine body. Detecting means, and height setting means for setting the height of the boom with respect to the traveling machine body, wherein the boom driven up and down based on the elevating command of the elevating operation tool for the boom is moved to the height set by the height setting means. An automatic stop means for linking the lifting / lowering operation tool, the height setting means, and the height detection means is provided so that the lifting / lowering movement is automatically stopped when the vertical position is reached.

According to a second aspect of the present invention, in the first aspect, after the lifting / lowering movement of the boom is stopped by the operation of the automatic stopping means, the lifting / lowering operation tool is returned to neutral once, and then the boom is moved in the same direction as the lifting / lowering movement before the stop. A re-elevating means is provided which is capable of elevating and lowering the boom past the stop position when the re-elevating operation is performed.

In a third aspect based on the first aspect, the apparatus further comprises upper limit setting means for setting a maximum rising position of the boom, and when the rising boom reaches the height set by the upper limit setting means, the rising movement is forcibly stopped. Equipped with upper limit stopping means,
When the set height position set by the upper limit setting means is lower than the set height set by the height setting means, the upper limit stop means is linked so as to operate prior to the automatic stop means.

In a fourth aspect based on the second aspect, there is provided an upper limit setting means for setting a maximum rising position of the boom, and when the rising boom reaches the height set by the upper limit setting means, the rising movement is forcibly stopped. Equipped with upper limit stopping means,
When the set height position set by the upper limit setting means is lower than the set height set by the height setting means, the upper limit stop means is linked so as to operate in preference to the automatic stop means, and after the upper limit stop means is operated, the lifting operation is performed. The apparatus is characterized in that the boom is raised so as to prevent the boom from rising above the height set by the upper limit setting means due to the operation of the tool.

According to the first aspect of the present invention, the operation of the automatic stop means is controlled so that the boom moving up or down by operating the lifting / lowering operation tool automatically stops when the boom reaches the set height. In other words, by setting a high or low dump position with a substantially fixed height as the set position,
By simply raising or lowering the boom, the boom can be automatically and reproducibly stopped at a predetermined position, so that the operation of stopping the boom at a fixed position is difficult and troublesome.

By the way, when the boom stopped by the function of the automatic stop means is desired to be raised or lowered further than the stop position, the automatic stop means may be released. When this happens, the stored set position is also released. That is, it is not suitable for use in which the automatic stop means is temporarily raised or lowered from the set position in a state where it functions, which is inconvenient. Therefore, in the configuration of claim 2, after the lifting / lowering movement of the boom is stopped by the automatic stopping means, the lifting / lowering operation tool is returned to neutral once, and if the lifting / lowering operation is performed again in the same direction as the lifting / lowering movement before the stop, the stop is performed. Since the re-elevating means that allows the boom to move up and down past the position functions, it is possible to move up and down beyond the stop position without releasing the automatic stopping means.
Then, if the lifting operation is performed to return the boom that has passed through to the original position, it is restored to the function state of the automatic stop means that stops the raising and lowering movement of the boom at the set height position, so there is no need to perform the resetting operation. .

According to the third aspect of the present invention, (a) the function of the upper limit stopping means automatically stops the upward movement of the boom when it rises to the set height position. This makes it possible to prevent interference between the ceiling and the working tool during the operation. If the stop position of the upper limit stop means is set lower than the stop position of the automatic stop means, the control is performed so as to stop at the lower position. This is advantageous because there is no inconvenience that the work tool interferes with the inner ceiling.

According to the configuration of the fourth aspect, the following operation is added in addition to the operation of the above (A). In other words, according to the second aspect of the invention, even if the automatic stop means is operated, if the neutral operation is performed once and then the elevating operation tool is operated to ascend, the elevating operation tool can be further moved past the stop position. If so, the control is performed so that even if the re-elevating operation is performed from the neutral position, the height does not exceed the height set by the upper limit setting means. Therefore, while adopting a convenient operation structure capable of temporarily releasing the function of the automatic stop means, the control function for preventing the contact with other objects due to the ascent is maintained.

[Effect] In the working machine according to the first aspect,
(A) Since the boom stops automatically at the height position determined by the automatic stop means, a lifting control device capable of efficiently and easily performing operations such as scooping of earth and sand and gravel can be provided.

In the working machine according to the second aspect of the present invention, (b) it is possible to move up and down past the stop position without releasing the automatic stop means, and it is possible to easily restore the original control state. The function of the automatic stop means is temporarily provided without performing the height resetting operation while having the effect of the above (a), such as dropping the earth and sand to a different place during the scooping operation of the earth and sand. There is an advantage that can be canceled.

In the working machine according to the third aspect, the upper limit stopping means prevents the working implement from being raised to a height higher than a preset level, and ensures that interference with other objects due to the raised work such as collision with the house ceiling is prevented. , And also has the effect (a).

According to a fourth aspect of the present invention, there is provided the working machine having the effects of the third aspect and the effect of the above (b), and the upper limit stop means can be prioritized even in the temporary release state of the automatic stop means. There is an advantage that a function of preventing interference with other objects can be obtained.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
A case of a tractor, which is an example of a work machine, will be described with reference to the drawings. 1 shows a tractor, 1 is a traveling body, 2 is an engine, 3 is a mission, 4 is a front wheel, 5 is a rear wheel, 6 is a front loader device, and 8 is a driving unit. The front loader device 6 includes the traveling body 1 as an implement.
It is detachably attached to.

As shown in FIGS. 1 and 3, the front loader device 6 includes a pair of left and right masts 12, 12, a pair of left and right booms 18, 18, and a pair of right and left boom cylinders 21, 12.
1, a bucket (an example of a working tool) 22, and a pair of left and right tilt cylinders 23, 23. The left and right support arms 16, 16 connected to each mast 12 and connected by a connection pipe 17 are connected to support portions 15 at the front end of the body.
The front loader device 6 is mounted on the traveling machine 1 by attaching the left and right masts 12, 12 to the left and right mounting portions 9, 9, respectively.

A hydraulic unit a provided with an electromagnetic control valve 26 for a boom cylinder, an electromagnetic control valve 27 for a tilt cylinder, etc., and a single joystick type operating lever 25 for operating these two control valves 26, 27 and its switch A control unit A including a unit and the like is provided on the side of the operation unit 8, and the hydraulic device unit a and the control unit A are detachable from the body. With the cross operation of the operation lever 25,
The single boom 18 can be raised and lowered, the bucket 22 can be raised and lowered independently, and the boom buckets 18 and 22 can be raised and lowered simultaneously.

FIG. 2 shows a hydraulic circuit, in which a hydraulic pump 36 is provided.
The basic circuit for supplying the discharge pressure of the tractor to a hydraulic device 35 including a lifting link mechanism and a front wheel speed-up mechanism at the rear of the tractor is provided with hydraulic supply blocks 32 and 33 for supplying pressure and returning oil, respectively. A pair of supply / drain oil passages 30, 30 of the hydraulic unit a are detachably mounted on the take-out blocks 32, 33.

The front loader device 6 is provided with an elevating control means B for maintaining the attitude of the bucket 22 with respect to the traveling machine body 1 regardless of the elevating of the boom 18. That is, as shown in FIGS. 1 and 2, a work implement posture detecting means C for detecting a posture of the bucket 22 with respect to the traveling
And a work implement posture setting means D for setting the posture of the bucket 22 with respect to the traveling machine body 1, and the posture of the bucket 22 is maintained at the target posture set by the work implement posture setting means D regardless of the swinging up and down movement of the boom 18. As described above, the control device 11 is provided to link the work implement lifting mechanism 23 that drives and swings the bucket 22 up and down, the work implement attitude detection means C, and the work implement attitude setting means D.

The lifting control means B will be described in detail. A first potentiometer 7 for detecting the angle of the boom 18 with respect to the mast 12 and a second potentiometer 10 for detecting the angle of the bucket 22 with respect to the boom 18 are provided. , 10 detects the angle (posture) of the bucket 22 with respect to the traveling body 1 by calculating from the detection values of the bucket 22, and the work implement posture setting means D by connecting the bucket switch 14 to the control device 11.
, And a work implement elevating mechanism is constituted by the tilt cylinder 23, and the elevating control means B is included in the control device 11.

In order to set the attitude of the bucket 22, first, the operating lever 25 is moved to actually swing and raise and lower the bucket 22, and when the desired attitude is visually observed, the bucket switch 14 is turned from the "OFF" position. The operation is completed by operating to the "enter" position. Of course, the operation lever 25 is returned to the neutral position in a desired posture, and then the bucket switch 1
4 may be operated. That is, bucket switch 1
4 is operated, the two potentiometers 7, 1
The angle (posture) of the bucket 22 with respect to the traveling body 1 is calculated by a calculation based on the detected value of 0 and stored as a target posture. Thereafter, the tilt is maintained so that the target posture is maintained regardless of how the operation lever 25 is operated. Electromagnetic control valve for cylinder 27
Is operated. To cancel the attitude maintaining control and return to the manual operation state, the bucket switch 14 is turned off.

Next, the automatic stopping means H, the re-elevating and lowering means I, the upper limit stopping means J and the linkage control means K, which are the lifting and lowering control relating to the boom, will be described. The automatic stop means H is a boom 1
Height detecting means h for detecting the height of the traveling body 1 with respect to the traveling body 8
a, and height setting means hb for setting the height of the boom 18 with respect to the traveling machine body 1. The boom 18 driven and raised based on a lifting / lowering command of an operation lever 25 which is a lifting / lowering operating tool for the boom, The operation lever 25, the height setting means hb, and the height detecting means ha are linked so that the ascent / descent is automatically stopped at the height position set by the height setting means hb.

After the lifting / lowering movement of the boom 18 is stopped by the operation of the automatic stopping means H, the re-raising / lowering means I returns the operating lever 25 to neutral once and then moves the boom 18 in the same direction as the lifting / lowering movement before the stop. When the elevating operation is performed, the boom 18 can be moved up and down past the stop position of the automatic stop means H.

The upper limit stopping means J includes upper limit setting means a for setting the maximum rising position of the boom 18, and when the rising boom 18 reaches the height set by the upper limit setting means a, the rising movement is forcibly stopped. It is to let. When the set height position set by the upper limit setting means a is lower than the set height set by the height setting means hb, the linkage control means K is linked so that the upper limit stop means J operates in preference to the automatic stop means H. After the operation of the upper limit stop means J, the boom is raised so as not to be higher than the height set by the upper limit setting means a due to the operation of the operation lever 25.

As shown in FIG. 2, a setting switch 29 is provided on the top of the operation lever 25, and an up switch 31 and a down switch 34 are provided on the side of the lever, respectively. The setting switch 29 includes a boom switch 38. In addition to being connected to the control device 11 via an on / off switch 39, an upper limit setting dial 40 is also connected via the on / off switch 39. An elevating speed setting device L is interposed between the controller A and the control device 11.

In the automatic stopping means H, the height of the boom 18 can be set at two positions, that is, an upper position and a lower position. The setting procedure is as follows.
Then, by operating the operation lever 25, the boom 18 is actually raised and lowered, and when the height is considered to be just right, the setting switch 29 is pressed and operated to complete one of the upper and lower height setting operations. I do. Next, the operation lever 25
Is operated to raise and lower the boom 18 again, and when the height is considered to be just right, the setting switch 2 is again set.
By pressing the button 9, the height setting operation of the other of the upper and lower sides is completed, and the position set by the setting switch 29 can be stored in up to two locations.
The height setting position may be set only on the upper side or only on the lower side.

After the upper and lower height positions are set, when the operating lever 25 is raised, the upward movement of the boom 18 is automatically stopped at the higher set height position, and the operating lever 25 is moved downward. It is controlled so that the lowering movement of the boom 18 is automatically stopped at the set height position on the lower side, which is suitable for earth and sand scooping work in which earth and sand scooping on the ground and loading on the truck bed are repeated. Then, in the repetitive work of the fixed upper and lower positions, the use of the up / down switches 31 and 34 makes it easier. That is, when the up switch 31 is pressed, the boom 18 is automatically turned on.
Is raised to the upper set height position, and the lowering switch 34
When the button is pressed, the boom 18 is automatically lowered to the lower set height position, so that the up / down operation over the upper and lower set heights can be performed without tilting the operation lever 25. . Of course, it is also possible to use only one of the switches 31 and 34 for raising and lowering.

After the automatic stopping means H has been set, the operation for raising and lowering to a higher or lower side than the set upper and lower heights is as follows. For example,
When the ascent is automatically stopped at the upper set height position when the boom 18 is moved upward by the operating lever 25, the operating lever 25 is returned to the neutral position once, and then is operated again to the ascending side. The boom 18 can be raised past the upper setting position. Similarly, when lowering, the control unit A is once again returned to neutral and then re-lowered. The re-elevating means I includes the control unit A as a part thereof.

To set the upper limit height of the boom 18 in order to avoid interference with the ceiling of the bucket 22 during house work or the like, first, turn on the on / off switch 39, and then turn the dial 40a to set the desired height. By setting the angle (boom angle with respect to traveling body, height with respect to traveling body, etc.), the process is completed. In other words, after the upper limit stopping means J is set, even if the boom 18 is raised, it is controlled so as to stop automatically when the boom 18 reaches the set upper limit height determined by the upper limit setting dial 40. The rise is blocked. As an actual setting example, for example, as shown in FIG.
The upper limit set by the upper limit stopping means J is set at the upper and lower set height positions by the automatic stop means H and at a position higher than the upper set height position.

The linkage control means K operates effectively when the upper set height by the automatic stop means H is higher than the upper limit height set by the upper limit stop means J. For example,
If the upper set height by the automatic stop means H is 3 meters with respect to the traveling body 1 and the upper limit height set by the upper limit stop means J is 2.5 meters, when the boom 18 is raised, 2. The control is performed so that the operation lever 25 is always stopped at 5 meters, and even if the operation lever 25 is returned to neutral once and then raised, the control is performed so that the operation lever 25 cannot be raised to 2.5 meters or more. That is, the automatic stopping means H
Priority is given to the upper limit stopping means J.

The elevating speed setting device L is provided with an ascending speed setting dial 41 and a descent speed setting dial 42.
Speed (the maximum speed of the tilt cylinder 23 may be used)
Is set. Each of the control valves 26 and 27 is an electromagnetic proportional valve, and is linked so that the valve opening increases as the tilt amount of the operation lever 25 increases. When the boom 18 or the like is slowly moved, the control lever 25 tilts. The amount is small, and when moving quickly, the amount of lever tilt is also large.

That is, as shown in the graph of FIG. 4, the tilt amount of the operation lever 25 and the cylinder driving speed are in a linearly proportional relationship, and the setting dials 41 and 42 set the cylinder maximum speed. . Therefore, for example, if the rising speed setting dial 41 is set to “standard”, the line i
, Set to "maximum" to line ii, and "minimum"
Is set to line iii. The relationship between the tilt amount of the operation lever 25 and the cylinder drive speed is
As shown in FIG. 5, a line graph that gradually increases up to a certain amount of tilting operation, and thereafter increases sharply thereafter may be used to facilitate the inching operation.

[Alternative Embodiment] In the upper limit stopping means J, the upper limit position of the boom 18 is set by the setting dial 40. The operating lever 25 is provided with another upper limit setting switch in addition to the setting switch 29. When the height is visually determined by actually operating the operation lever 25, the upper limit setting switch may be pressed to determine the height.

Forks may be mounted instead of buckets, and these are collectively called "work implements".

[Brief description of the drawings]

FIG. 1 is a side view of a tractor with a front loader device.

FIG. 2 is a hydraulic circuit and control system diagram relating to a front loader.

FIG. 3 is an operation diagram showing functions of an automatic stop unit and an upper limit stop unit.

FIG. 4 is a diagram showing a relationship graph between a lever tilt amount and a cylinder speed.

FIG. 5 is a graph showing another relationship graph between a lever tilt amount and a cylinder speed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Traveling body 18 Boom 22 Work implement 25 Elevating operation implement for work implement H Automatic stopping means I Re-elevating means J Upper limit stopping means a Upper limit setting means ha Height detecting means hb Height setting means

Claims (4)

[Claims] An elevation control device for a working machine, which is connected to a machine body so as to be capable of swinging and lowering a boom having a working tool connected to a tip thereof, wherein the height detecting means detects a height of the boom with respect to a traveling machine body. Detecting means and height setting means for setting the height of the boom with respect to the traveling machine body are provided, and the boom driven and lowered based on a lifting / lowering command of a lifting / lowering operating tool for the boom is set by the height setting means. Lifting / lowering control of a working machine having an automatic stopping means for linking the lifting / lowering operating tool, the height setting means, and the height detecting means so that the lifting / lowering movement is automatically stopped when the height position is reached. apparatus. 2. After the elevating operation of the boom is stopped by the operation of the automatic stop means, the elevating operation tool is once returned to neutral, and then the boom is re-elevated in the same direction as the elevating movement before the stop. The lifting / lowering control device for a working machine according to claim 1, further comprising a re-elevating means capable of elevating and lowering the boom past the stop position. 3. An upper limit setting means for setting a maximum rising position of the boom, and an upper limit stopping means for forcibly stopping the rising movement when the rising boom reaches the height set by the upper limit setting means. The apparatus according to claim 1, wherein the upper limit stop means is operated in preference to the automatic stop means when the set height position set by the upper limit set means is lower than the set height set by the height set means. The lifting / lowering control device for the working machine described in the above. 4. An upper limit setting means for setting a maximum rising position of the boom, and an upper limit stopping means for forcibly stopping the rising movement when the rising boom reaches the height set by the upper limit setting means. When the set height position set by the upper limit setting means is lower than the set height set by the height setting means, the upper limit stop means is linked to operate in preference to the automatic stop means, and the upper limit stop is performed. 3. The lifting and lowering of the working machine according to claim 2, wherein after the operation of the means, the lifting of the boom to a height higher than the height set by the upper limit setting means due to the operation of the lifting and lowering operation tool is prevented. Control device.