JPH053365U - Loader control device - Google Patents

Abstract

(57) [Summary] [Structure] In a structure including a loader hydraulic lifting member (23) for manually or automatically lowering the lifting arm (11) of the loader (9) with hydraulic pressure, the lifting arm (11) is A floating switch (57) for floating operation, which is lowered by its own weight, is provided, and when the floating switch (57) is turned on, the lifting member (2)
According to 3), when the loader is below the set height, the floating operation is performed. [Effect] The floating operation performed by the conventional hydraulic lever or the like can be performed without fixing the hydraulic lever to the floating position, and safety and workability can be improved.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a control device for a loader such as a front loader which is mounted on the front part of a traveling machine such as a tractor and is used for loading or digging or burying compost or hay, arranging a field for leveling or snow removal.

[0002]

[Prior Art]

 In this type of front loader, the mechanical valve is used for the natural lowering or floating operation of the various attachments such as buckets attached to the tip of the lifting arm by its own weight by fixing the hydraulic lever to the floating position.

[0003]

[Problems to be solved by the device]

 However, in a system in which the front loader is controlled by a microcomputer, if one joystick is used to raise and lower the lifting arm, dump the bucket, and scoop, the floating must be performed with another switch. In this case, the operability is inferior to the mechanical valve. Therefore, it is possible to position the floating switch on the head of the joystick to start the floating operation, but it is very dangerous because the floating operation is started from the high position of the lifting arm. was there.

[0004]

[Means for Solving the Problems]

 Therefore, the present invention provides a floating switch for floating operation for lowering the lifting arm by its own weight in a structure including a loader hydraulic lifting member for manually or automatically lowering the lifting arm of the loader with hydraulic pressure. The floating operation is performed when the loader is below the set height by the elevating member when the turning switch is turned on.

[0005]

Embodiment An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a control circuit diagram of the front loader, FIG. 2 is a side view of the whole, and FIG. 3 is a side view of the front loader. In the figure, (1) is a tractor that is a traveling vehicle, and (2) and (3) are tractors. Front and rear wheels of (1), (4) is a chassis that is a machine for mounting front wheels (2), (5) is an engine mounted on the chassis (4), and (6) is an engine mounted on the engine (5). A power transmission case for installing the rear wheels (3), (7) a driver's seat mounted on the upper rear surface of the case (6), (8) a steering handle, A bucket (10) as an attachment is installed in front of the tractor (1) via a pair of left and right lift arms (11). Further, in the figure, (12) is a rear mounting frame that supports the lift arm (11), (13) is a horizontal mounting frame in which the rear end is integrally connected to the rear mounting frame (12), and (14) is a horizontal mounting frame. This is a front mounting frame that is integrally connected to the front end side of the frame (13). Each of the frames (12), (13) and (14) is formed in a side view gate shape, and is fixed to the lower surface side of the power transmission case (6). The rear mounting frame (12) is erected on the base mount (15) to be installed via the rear mounting base (16), and the front part is attached to the front end side of the chassis (4) via the front mounting base (17). The portal frames are vertically installed on the mounting frame (14), and the gate-shaped frames (12), (13) and (14) are installed symmetrically on both sides of the bonnet (18) that covers the engine (5).

Further, the base end of the lift arm (11) is connected to and supported by the upper end of the front attachment frame (12) via a pivot fulcrum pin (19), and the frame (12) and the lift arm are also supported. (11) A loader elevating cylinder (23), which is an elevating member, is provided via a pin (21) (22) between it and an intermediate fixed locking plate (20). The lift arm (11) is constructed so as to be appropriately moved up and down.

Further, a dump cylinder (28) is attached to fixed brackets (24) (25) which are fixed mounting plates between the middle and the front end of the lift arm (11) via swinging pins (26) (27). And each base end of the dump arm (29) is supported, the tip ends of the cylinder (28) and the arm (29) are connected to each other through a pin (30), and the arm is provided at the rear upper end of the bucket (10). (29) The tip is interlockingly connected via a pin (31), an upper hook arm (32) and a dump link (33). Then, the lower rear end of the bucket (10) is supported on the front end of the lift arm (11) via a pin (34) and a lower hook arm (35), and the bucket cylinder (28) is expanded and contracted by the expansion and contraction operation of the bucket. The inclination of (10) is appropriately changed.

Further, an obliquely upward opening notch (37) is formed on the intermediate front side of the rear mounting base (16) via a hook arm (36), and a horizontal opening notch (37) is formed at the upper front side of the rear mounting base (16). 38), and a pair of leg plates (39) (39) are integrally formed on the lower end side of the rear mounting frame (12) to form a rear view and a downward wide outer shape. ) (40) is formed at the lower end of the leg plates (39) (39), while locking pins (41) (42) for engaging the notches (37) (38) are provided between the leg plates (39) (39). It is fixed laterally integrally.

After the pin (41) is engaged with the notch (37) by the guide of the hook arm (36), the rear mounting frame (12) is displaced around the pin (41) to move the notch (38). The pin (42) is engaged with the rear part of the tractor (1). The left and right rear parts of the tractor (1) are connected to the left and right mounting bases (16) (16) from the upper front side by the connecting pipe (43). The mounting frames (12) and (12) are configured to be engaged and fixed only by tilting forward and detaching independently.

Further, while holding rod-shaped bodies (44), which are lock pins, are horizontally mounted between the lower ends of the left and right front mounting frames (14) (14), the front mounting base (17) has a rectangular cylindrical holding box. (45) is integrally formed, and the cam member (46) is detachably locked to the box (45). The rod-shaped body (44) is inserted into the lower notch of the lower surface of the box (45) from below. The front mounting frame (14) is engaged and fixed to the front mounting base (17) from the lower side by engaging with the cam member (46).

Further, as shown in FIGS. 2, 5 and 6, a controller (47) for controlling the operation of the cylinders (23) (28) is provided with a support arm (48) on the right side of the driver's seat (7). It is detachably attached via a neutral return type joystick type manual lever (49) that can swing in 8 directions, and a neutral return type one-touch lever that automatically raises and lowers the lift arm (11) to a set height. (50), a variable resistor type lift arm lower limit setting volume (51) for setting the automatic lowering height of the lift arm (11), and a one-touch switching switch for turning on / off the automatic lifting control of the one-touch lever (50). (52) and a horizontal grounding switch for turning on / off the horizontal grounding control for making the bucket (10) parallel to the tractor (1) near the ground by lowering the lift arm (11). The switch (53), the bucket setting volume (54) for adjusting the horizontal (parallel) state of the bucket (10) with respect to the tractor (1) body, and the attachment / detachment of the controller (47) with respect to the support arm (48) are detected. A controller attachment / detachment switch (55) is provided on the controller (47), and a lift arm potentiometer (56) for raising and lowering which is interlocked with the forward and backward tilting of the manual lever (49), and the manual lever (49). ) A lock-type floating switch (57) that is provided in the vicinity to freely lower the lift arm (11) by its own weight during the lowering operation, and a dump and rake for interlocking with the left and right tilt of the manual lever (49). A raising / lowering switch (5) which is switched and operated by the bucket potentiometer (58) and the one-touch lever (50). ), Etc., it is provided to the controller (47).

Further, as shown in FIG. 1, a loader control circuit (60) composed of a microcomputer is internally provided in the controller (47), and each volume (51) (54) and each switch (52) (53) ( 55) (57) (59) and each potentiometer (56) (58) are connected to the circuit (60), a power switch (61) for applying a drive power to the circuit (60) is provided, and the tractor is provided. The switch (61) is connected to the battery (64) via the key switch (62) of (1), the fuse (63), and the like.

In addition, through the stroke-electric capacitance variable lift arm position sensor (65) mounted in parallel to the loader lifting cylinder (23) via the pins (21) and (22), and via the pins (26) and (30), And a lift electrostatic capacity variable bucket position sensor (66), which are mounted in parallel to the dump cylinder (28), and the lift arm (11) and the bucket () by the sensors (65) (66) connected to the circuit (60). 10) The support height and posture of the load cylinder are detected, and the lift arm raising electromagnetic solenoid (67) and the lift arm lowering electromagnetic solenoid (68) for expanding and contracting the loader raising and lowering cylinder (23) are connected to the dump cylinder (28). A bucket dump electromagnetic solenoid (69) and a bucket scooping electromagnetic solenoid (70) for expanding and contracting are provided, Each solenoid (67)-(70) is output-connected to the control circuit (60).

Further, a light emitting diode (71) for indicating the runaway of the control circuit (60) by turning off the light is provided, and each volume (51) (54), each potentio (56) (58) and each sensor (65) ( The abnormal input of 66) is displayed by turning on the light emitting diode (71), and the state that all parts are normal is displayed by blinking the light emitting diode (71).

Further, as shown in FIG. 7, a closed center type constant pressure type hydraulic circuit (72) for controlling the operation of the front loader (9) is provided, and the lifting control for controlling the operation of the loader lifting cylinder (23) is provided. A valve (73) and a dump scooping valve (74) for controlling the operation of the dump cylinder (28) are provided, and the high pressure oil of the hydraulic pump (75) is supplied to each cylinder (23) (via each valve (73) (74). 28) and the solenoids (67) (68) (69) (70) and the pilot control cylinders (76) (77) for switching the valves (73) (74). And the pilot operating valves (78) (79) (80) (81) for raising and lowering and for dumping and scooping for operating the operating cylinders (76) (77). The operation valves (78) to (81) are switched by pulse control to operate the solenoids (67) to (70) by the pulse signal output of the loader control circuit (60), and the operation cylinders (76). (77) is operated to switch each control valve (73) (74) and each cylinder (23) (28) is operated to lower the front loader (9) and lower it. Dump operation, dump operation performed at a constant height, dump operation performed by rising, raising operation, scooping operation performed by rising, scooping operation performed at constant height, scooping operation performed by descending It is configured to operate.

By the way, while a poppet valve (82) for constant pressure is provided in the main hydraulic pressure supply line (72a) of the hydraulic circuit (72), at the front of the hydraulic pressure supply inlet of the hydraulic circuit (72), A solenoid (83) operated two-port two-position shut-off valve (84) that normally shuts off the supply of hydraulic pressure is provided, and this solenoid (83) is connected to the control circuit (60) for output connection. The solenoids (83) are excited only when the valves (73) (74) are switched from the neutral position by the excitation of 67) to (70) and the poppet valve (82) is in the open operation start state. The shut-off valve (84) is opened so that pilot oil for operating the poppet valve (82) is not normally supplied to the hydraulic circuit (72).

This embodiment is configured as described above, and FIG. 8 is a flow chart showing a check operation. When the power switch (61) is turned on, the loader control circuit (60) runs out of control. If the LED is turned off, the light emitting diode (71) is turned off, and if the check in FIGS. 9 to 14 is abnormal, the light emitting diode (71) is turned on. ) Blinks, and an abnormal condition and a normal condition are indicated by the light emitting diode (71).

FIG. 9 is a flow chart showing the bucket potentiometer (58) check. When the input from the bucket potentiometer (58) is too large or too small as compared with the dump or scoop control range, the light emitting diode (71) is turned on. It is lit to indicate an abnormal input, and the bucket (10) manual operation based on the bucket potentiometer (58) input operated by the manual lever (49) is prohibited.

FIG. 10 is a flowchart showing the check of the bucket position sensor (66). When the input from the bucket position sensor (66) is too large or too small as compared with the dump or scoop control range, the light emitting diode (71) is turned on. In addition to displaying the abnormal input, the input from the bucket position sensor (66), the horizontal grounding operation shown in FIG. 18, and the parallel operation shown in FIG. 19 are prohibited, and the dump cylinder (28) is operated. The bucket (10) is automatically returned until the input of the bucket position sensor (66) is within the proper input range, and the prohibitions are released.

FIG. 11 is a flow chart showing the lift arm potentiometer (56) check. When the input from the lift arm potentiometer (56) is too large or too small as compared with the rising or falling control range, the light emitting diode (71) is shown. Is displayed to indicate an abnormal input, and the lift arm (11) manual operation based on the lift arm potentiometer (56) input operated by the manual lever (49) is prohibited.

FIG. 12 is a flow chart showing a check of the lift arm position sensor (65). When the input from the lift arm position sensor (65) is too large or too small as compared with the rising or falling control range, the light emitting diode ( 71) is turned on to indicate an abnormal input, and the inputs from the lift arm position sensor (65), horizontal grounding operation shown in FIG. 18, parallel operation shown in FIG. 19, and one-touch operation shown in FIG. 17 are prohibited. By operating the loader lifting cylinder (23), the lift arm (11) is automatically returned until the input of the lift arm position sensor (65) is within the proper input range, and the above prohibitions are released.

FIG. 13 is a flow chart showing the lift arm lower limit setting volume (51) check. When the input from the lift arm lower limit setting volume (51) is too large or too small from the rising or falling control range, the light emitting diode is shown. (71) is lit to indicate the abnormal input, and the lift arm lower limit setting volume (51) is automatically set to an intermediate value between the lowest set value and the highest set value as the input of the volume (51). With the output of the volume control (51) fixed in the neutral position, the lift arm (11) is returned to and supported between the neutral position and the lowest position of the lifting range.

FIG. 14 is a flow chart showing the check of the bucket setting volume (54). When the input from the bucket setting volume (54) is too large or too small for the dump or scoop control range, the light emitting diode (71) is shown. Is displayed to indicate an abnormal input, and an intermediate value between the minimum setting value and the maximum setting value of the bucket setting volume (54) is automatically set as the input of the volume (54), and the output of the volume (54) is displayed. With the neutral state fixed, return the bucket (10) to the dump posture and support it.

Further, FIG. 15 is a flow chart showing the manual operation of the bucket (10), and when the manual lever (49) is dumped or scooped, the input of the bucket potentiometer (58) which operates with the manual lever (49) is shown. The duty ratio of the dump or scoop control pulse signal that drives the solenoids (72) (73) is changed in proportion to the difference from the neutral position value, and the dump cylinder (28) is adjusted by adjusting the hydraulic flow rate by pulse signal control. The speed is controlled, and the bucket control (10) is dumped or scooped by pulse control that makes the cylinder (28) move faster as the operation amount of the manual lever (49) is larger, and the bucket potentiometer (58) is input. Cylinder (28) before the bucket (10) stop position where the input and the bucket position sensor (66) input match A cushion operation for gradually reducing the driving speed is performed by pulse control, and the bucket (10) is stopped at a predetermined position.

FIG. 16 is a flowchart showing the manual operation of the lift arm (11). When the manual lever (49) is moved down or up, the lift arm potentiometer (56) input that operates with the manual lever (49) is input. The duty ratio of the descending or ascending control pulse signal for driving the solenoids (67) and (68) is changed in proportion to the difference between the neutral position and the value of the neutral position, and the loader elevating cylinder is adjusted by adjusting the hydraulic flow rate by pulse signal control. (23) is speed-controlled. The larger the operation amount of the manual lever (49), the faster the lift arm (11) is lowered or raised by the pulse control that makes the cylinder (23) move faster. Before the lift arm (11) stop position where the arm potentiometer (56) input and the lift arm position sensor (65) input match A cushion operation for gradually reducing the driving speed of the cylinder (23) is performed by pulse control, and the lift arm (11) is stopped at a predetermined height position.

Further, FIG. 17 is a flow chart showing a one-touch operation for automatically raising and lowering the lift arm (11) to a set height. When the controller attachment / detachment switch (55) is turned on, the mounting of the controller (47) is confirmed. , When the one-touch changeover switch (52) is turned on, the one-touch lever (50) is raised and lowered, and the lift arm (11) is automatically moved when the raising and lowering switch (59) is switched to the up or down side. The lift arm is set to the lower limit setting position of the lift arm lower limit setting volume (51) which can be freely set to any height by lowering the one-touch lever (50). While moving (11) up and down, the one-touch lever (50) is moved up and the fixed one The lift arm (11) is moved up and down by a pulse-controlled speed adjustment to a lifting position at a constant height, and a cushion operation for gradually decelerating before a predetermined stop position is performed by pulse control. ) Is stopped, and the lift arm (11) is automatically lifted and supported at the lower limit setting position of the volume control (51) or a fixed lifting position of a constant height.

When the switches (52) and (55) are turned off, the one-touch operation is instantly stopped to stop the output, and when the power switch (61) is turned on, the one-touch operation is performed. Even if the condition is satisfied, the one-touch operation is not performed. In this case, the one-touch operation is performed by satisfying again after the operating condition is not satisfied.

Further, FIG. 18 is a flowchart showing a horizontal grounding operation for supporting the bucket (10) with respect to the tractor (1) and the main body in a predetermined posture (normal). When the controller attachment / detachment switch (55) is turned on, the horizontal grounding operation is performed. When the ground switch (53) is turned on, the bucket (10) of FIG. 15 is manually operated by lowering the lift arm (11) by the manual operation of FIG. 16 or the one-touch operation of FIG. In the state where the bucket (10) is in the horizontal (parallel) state with respect to the machine, the setting value of the bucket setting volume (54) is input, and the volume (54) input and each sensor (65) (66) are input. Based on the input, the bucket (10) is controlled to a horizontal grounding posture in cooperation with the lowering of the lift arm (11), and the bucket is held in a fixed posture with respect to the tractor (1) body. The lift cylinder (10) is supported and lowered, and the dump cylinder (28) is operated at the faster of the control speed proportional to the lowering speed of the lift arm (11) and the step drive speed of an ideal value to lift. The bucket (10) is moved to the horizontal grounding posture at the faster of the calculated speed based on the speed of the arm (11) and the set speed, and even if the lift arm (11) descends and reaches a predetermined speed, ) Is not on the scooping side and is not in the horizontal grounding posture, the lifting of the lift arm (11) is stopped, the horizontal grounding posture control of the bucket (10) is continued, and the horizontal landing of the bucket (10) is continued. When the bucket (10) is horizontal (parallel) to the tractor (1) by performing only the operation, the lowering of the lift arm (11) is started by the manual lowering operation of FIG. ) Notwithstanding et bucket is lowered (10) performs a horizontal ground attitude control, to stop the lift arm (11) in place by the cushion operation to gradually decelerated, for supporting the bucket (10) in a horizontal position. In addition, when the horizontal grounding is stopped by the bucket manual operation in FIG. 15, the horizontal grounding is restarted by the manual release, and the lift arm (11) in FIG. 16 is manually raised during the horizontal grounding operation. The horizontal grounding operation is stopped and the parallel operation control of FIG. 19 is performed. When one of the switches (53) and (55) is turned off, the horizontal grounding operation is stopped after controlling the bucket (10) to the neutral position.

Further, FIG. 19 is a flow chart showing a parallel operation for raising and lowering the bucket (10) in a substantially constant posture. When the controller attachment / detachment switch (55) is turned on, the lift is performed by the manual operation of FIG. 16 or the one-touch operation of FIG. By moving the arm (11) up and down, the bucket (10) position relative to the tractor (1) immediately before the lift arm (11) ascends or descends when the bucket (10) of FIG. 15 is not manually operated. , Or the position of the bucket (10) immediately after stopping when the lift arm (11) is moving up and down and the bucket (10) is moved. The speed of the dump cylinder (28) that operates the bucket (10) in proportion to the lifting speed of the The lift arm (11) is stopped at a predetermined position by increasing the scooping speed as compared with the dump speed of the bed (10) and gradually decreasing the cushioning speed. In addition, the parallel operation is stopped by the bucket manual operation in FIG. 15, the parallel operation is restarted by the manual release, and when the switch (55) is turned off during the parallel operation, the bucket (10) is moved to the ideal position. Then, after supporting the robot in a neutral position, parallel movement is stopped.

Further, FIG. 20 is a flow chart showing the continuous operation restriction for restricting the operation of each solenoid (67) to (70) to prevent thermal destruction of these power supply circuits, and FIGS. When the predetermined time has passed, the control output of the lift arm (11) and the bucket (10) is stopped, and the power circuits of the solenoids (67) to (70) are turned on. After turning off and resetting all the loader control circuit (60), it returns to the first check operation and restarts control by continuous operation (pulse signal output off), and when a certain time has elapsed, each solenoid (67) To (70) are operated by pulse signals to adjust the control speeds of the cylinders (23) and (28) to perform the respective operations of FIGS. 15 to 19.

21 to 23 are flowcharts showing a floating operation of freely lowering the lift arm (11) by its own weight. The floating switch (57) and the horizontal grounding switch (53) are turned on and the manual lever is turned on. When the lift arm potentiometer (56) is operated by (49) and the lift arm (11) is lowered, the lift arm position sensor (65) is lowered by the horizontal grounding operation of FIG. ), The descending solenoid (68) is continuously operated to continuously drive the elevating control valve (73) to the descending side to enter the floating operation. When the switches (57) and (53) are turned on and the one-touch changeover switch (52) is turned on to perform the one-touch lowering operation, the one-touch and horizontal grounding operations shown in FIGS. When the sensor (65) detects the height of the lift arm (11) or less, the descending solenoid (68) is continuously operated to continuously drive the elevating control valve (73) to the descending side for floating operation. Enter

On the other hand, when the floating switch (57) is on, the horizontal grounding switch (53) is off, and the lift arm potentiometer (56) is operated by the manual lever (49) to lower the lift arm (11). When the position of the position sensor (65) detects that the height of the lift arm (11) is below a certain height, the valve (73) is continuously driven downward as described above, when the lift arm is manually moved down as shown in FIG. Then start floating operation. When the floating switch (57) is turned on, the horizontal grounding switch (53) is turned off, and the one-touch changeover switch (52) is turned on so that the one-touch lowering operation is performed, the one-touch manual operation shown in FIG. When the sensor (65) is in a state of detecting the height of the lift arm (11) or less, the floating operation is started as described above.

During such a floating operation, when the lift arm (11) is operated by the manual lever (49) or the one-touch lever (50) to the ascending side, this ascending operation is prioritized and the ascending operation is performed. Even after the end of the operation, the floating operation is started when the sensor (65) detects the height of the lift arm (11) or less. When the bucket (10) is manually operated during such a floating operation, the control valve (73) of the lift arm (11) is continuously driven downward and the valve (74) on the bucket side is used. ) Is also driven. In addition, in the horizontal grounding operation under the condition that the lift arm position sensor (65) detects the height of the lift arm (11) or less, it is assumed that the detected value of this position sensor (65) is fixed. The operation of the bucket (10) is controlled by the value.

In other words, the release of this operation is more than the set height by the manual raising operation or the automatic raising operation even if the floating switch (57) is turned off or the floating switch (57) is still turned on. This is sometimes done, but the floating operation is not canceled even if the arm (11) height exceeds the set height due to external factors. In addition, even during floating operation, scooping by the manual lever (49) and dump operation can be performed. Further, when the floating operation is started during the horizontal grounding operation, the bucket (10) is not moved to the angle calculated from the angle of the arm (11) like the normal horizontal grounding operation, but is set to the set bucket (10). Move to an angle. This is to prevent the hunting state from occurring because the bucket (10) angle constantly changes because the arm (11) moves freely in the floating state.

Further, FIG. 24 is a flow chart in which the solenoid (83) is excited to open the shut valve (84) only while the valves (73) and (74) are operated by pulse control. Yes, in any of the bucket manual operation in FIG. 15, the lift arm manual operation in FIG. 16, the one-touch operation in FIG. 17, the horizontal grounding operation in FIG. 18, and the parallel operation in FIG. When the poppet valve (82) is turned on when any one of 67) to (70) is excited to start the operation of the valve (73) or (74), the solenoid (83) of the shut valve (84) is turned on. When the poppet valve (82) is excited and driven to open, the shut valve (84) is opened and controlled. After this operation is completed, when the poppet valve (82) is closed, that is, when the pulse operation signal to the solenoids (67) to (70) is stopped, as shown in FIG. 25, the shut valve (84) is shut off after a certain off delay time (T). The excitation of the solenoid (83) is released, and the hydraulic pressure supply to the hydraulic circuit (72) is shut off by the shut valve (84). In this case, the shut valve (84) may be provided with a minute on-delay time.

[0036]

[Effect of the device]

 As is apparent from the above embodiments, the present invention is a structure including a loader hydraulic lifting member (23) for manually or automatically lowering the lifting arm (11) of the loader (9) with hydraulic pressure, in which the lifting arm is provided. A floating switch (57) for floating operation for lowering (11) by its own weight is provided, and when the floating switch (57) is turned on, the loader is moved below the set height by the lifting member (23). In this case, it is possible to perform floating operation, so for example, like a mechanical valve that fixes a hydraulic lever at a floating position to perform floating operation, floating work can be done without releasing it. Since the lever is not locked to the It made a preparative possible to, a marked effect like can be improved safety and operability in the floating operation.

[Brief description of drawings]

FIG. 1 is a loader control circuit diagram.

FIG. 2 is an overall side view.

FIG. 3 is a side view of the loader.

FIG. 4 is a plan view of a loader.

FIG. 5 is a front view of the controller.

FIG. 6 is a side view of the controller.

FIG. 7 is a hydraulic circuit diagram of the loader.

FIG. 8 is a flowchart.

FIG. 9 is a flowchart.

FIG. 10 is a flowchart.

FIG. 11 is a flowchart.

FIG. 12 is a flowchart.

FIG. 13 is a flowchart.

FIG. 14 is a flowchart.

FIG. 15 is a flowchart.

FIG. 16 is a flowchart.

FIG. 17 is a flowchart.

FIG. 18 is a flowchart.

FIG. 19 is a flowchart.

FIG. 20 is a flowchart.

FIG. 21 is a flowchart.

FIG. 22 is a flowchart.

FIG. 23 is a flowchart.

FIG. 24 is a flowchart.

FIG. 25 is a time chart.

[Explanation of symbols]

 (11) Arm (23) Lifting cylinder (lifting member) (57) Floating switch

Claims (1)

Claims for utility model registration 1. A structure having a loader hydraulic lifting member for manually or automatically lowering an elevating arm of a loader with hydraulic pressure, for a floating operation of lowering the elevating arm by its own weight. With a floating switch,
A loader control device configured to perform a floating operation when the loader is below a set height by the elevating member when the floating switch is turned on.