JPH11127609A - Lift-controlling structure of working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lift-controlling structure of a working machine capable of performing the soil-shredding work with a working apparatus in floated state and preventing the damage of the working apparatus caused by the soil- shredding work. SOLUTION: A working apparatus A is connected to a mobile machine body 1 through a lifting link mechanism 4 in such a manner as to lift or lower the apparatus by the action of a hydraulic cylinder 3. The lift-controlling structure of a working machine having the above construction is provided with a floating control means capable of developing a floating state to lower the pressure in the hydraulic cylinder 3 to a preset low level, in the lowering operation and a waiting state to control the pressure in a hydraulic circuit of the hydraulic cylinder to a preset high level and keep the state after supplying or discharging a hydraulic oil to the hydraulic cylinder within the operation period in the lifting or lowering operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling machine, in which a working device such as a mowing device, a grass collecting device or a snow removing device is connected via a lifting link mechanism so as to be driven up and down by operation of a hydraulic cylinder. The present invention relates to a lifting and lowering control structure of a working machine for mowing or removing snow.

[0002]

2. Description of the Related Art Conventionally, in a lifting and lowering control structure of a working machine for mowing or removing snow as described above, a lowering operation state for lowering a pressure in a hydraulic cylinder for driving up and down a working device during a running operation is maintained. Thus, there has been a configuration in which a floating control is performed in which the grounding body mounted on the working device follows the ground on the ground and the working device is positioned at a predetermined height above ground.

[0003]

However, in the above-mentioned prior art, the working device is maintained at a predetermined ground height by maintaining the descent operation state for reducing the pressure in the hydraulic cylinder and causing the ground contact body to follow the ground. As a result, the entire weight of the working device is applied to the ground during work traveling. Therefore, when the work site is soft, the ground contact body sinks into the ground, and the work device causes earth removal, and the earth removal may cause damage to the work device.

[0004] It is an object of the present invention to provide a lifting and lowering control structure of a working machine capable of preventing earthwork by a working machine in a floating state and damage to the working machine due to the earth shaving.

[0005]

In order to achieve the above object, according to the first aspect of the present invention, a working device is mounted on a traveling body by a lifting / lowering link mechanism so as to be driven up and down by operation of a hydraulic cylinder. In the lifting and lowering control structure of the working machine connected via a, a floating state in which the pressure in the hydraulic cylinder is reduced to a preset lower side set value during the lowering operation, and only during the operation time during the lifting and lowering operation After supplying and discharging the hydraulic oil to and from the hydraulic cylinder, a floating state appears in which a standby state in which the pressure in the hydraulic circuit for the hydraulic cylinder is adjusted to a preset high-side set value and the state is maintained. Control means were provided.

According to the first aspect of the present invention, when a floating state in which the working device is positioned at a predetermined ground height by causing the ground contact body to follow the ground to the ground appears, the hydraulic cylinder in the hydraulic cylinder is brought into operation. The pressure is reduced only to a preset lower value. That is,
The hydraulic cylinder receives the weight of the working device according to the lower set value, and the weight (ground pressure) of the working device on the ground can be reduced by that much. As a result, even if the work site is soft, it is possible to prevent the ground contact body from digging into the ground when the floating state appears, thereby causing the work device to perform earth removal and damage to the work device caused by the earth removal. Can be prevented.

[0007] When the standby state appears,
After raising / lowering operation, supply / discharge operation of hydraulic oil to / from the hydraulic cylinder is performed to increase or decrease the pressure in the hydraulic cylinder to produce a desired elevating state, the pressure in the hydraulic circuit for the hydraulic cylinder is set in advance. Since the state is maintained by adjusting to the higher set value, by setting the higher set value to a value that is balanced with the weight of the work equipment, the pressure in the hydraulic circuit with respect to the hydraulic cylinder is not increased. Due to the necessity of lowering, the working device may suddenly drop during the lowering operation, or the working device may drop once and then rise during the ascent operation, or may cause an inconvenience to the hydraulic cylinder. Due to the pressure in the hydraulic circuit becoming unnecessarily high, the working equipment rises rapidly during the ascent operation, or once the working equipment rises during the descending operation. To et lowered, it becomes possible to prevent occurs that disadvantage.

[Effect] Accordingly, a part of the weight of the working device, which can prevent earth shaving by the working device and damage to the working device due to it, and can trim the grass grown on the ground to a predetermined ground height. Work that can show a floating state in which the work equipment is left on the ground, and when the work equipment is lifted and lowered, the work equipment does not move up and down suddenly and does not move once in the opposite direction. It has become possible to provide an elevator control structure.

According to the second aspect of the present invention,
The invention according to claim 1, further comprising a setting device for changing the setting value of the lower side.

According to the second aspect of the present invention, for example, when the work site is softer, the setting value of the lower side is changed to the higher side by the setting device in accordance with the degree of floating, so that the floating position is changed. In this state, the pressure in the hydraulic cylinder can be increased, whereby the proportion of the weight of the working device received by the hydraulic cylinder can be increased, and the weight of the working device applied to the ground (ground pressure) ) Can be reduced, so that the grounding body can be more effectively prevented from sinking into the ground when the floating state appears. If the work object (grass in the case of a mower and snow in the case of a snowplow) is relatively hard or has a large amount, the lower side of the setting device is set in accordance with the degree. By changing the set value of the hydraulic cylinder to the lower side, the pressure in the hydraulic cylinder in the floating state can be reduced, thereby reducing the proportion of the weight of the working device received by the hydraulic cylinder. Therefore, the weight (ground pressure) of the working device applied to the ground can be increased by that much, so that the working device can be prevented from rising due to the resistance of the work object, so that the working height position is unnecessary. Can be avoided.

[Effect] Therefore, it is possible to provide a lifting and lowering control structure of a working machine which can easily show an appropriate floating state according to the situation of a work place and more effectively obtain good work results. Reached.

According to the third aspect of the present invention,
The invention according to claim 2, further comprising a selection unit for selecting the type of the working device, and based on the selection of the selection unit, the floating control unit changes the setting value of the higher side, The output rotation speed of the PTO shaft that drives the working device is configured to be changed.

According to the third aspect of the present invention, by selecting the type of the working device connected to the traveling body by operating the selection means, the higher set value can be set for the work connected to the traveling body. When the standby state is revealed by setting the values to the values corresponding to the weights of the respective working devices connected to the traveling aircraft because the settings can be changed to the values corresponding to the types of the devices. In any case, regardless of the type of working device, after performing the operation of supplying and discharging hydraulic oil to the hydraulic cylinder by raising and lowering operation to raise or lower the pressure in the hydraulic cylinder to produce a desired lifting state, The pressure in the hydraulic circuit is adjusted to a higher set value that balances the type of the working device connected to the traveling vehicle, and the state is maintained. As a result, the working device drops suddenly during the lowering operation or the working device lowers once during the raising operation due to the pressure in the hydraulic circuit for the hydraulic cylinder becoming unnecessarily low. Due to the inconvenience of ascending, or the pressure in the hydraulic circuit to the hydraulic cylinder becoming unnecessarily high, the working device suddenly rises during the ascent operation, or the It is possible to prevent the inconvenience that the device rises and then descends once, regardless of the type of working device connected to the traveling body.

By selecting the type of the working device connected to the traveling machine by operating the selecting means, the output rotation speed of the PTO shaft for driving the working device can be adjusted according to the type of the working device connected to the traveling machine. Values can be changed to the rated values of each working device connected to the traveling machine, thereby preventing work failure due to insufficient output and damage to working devices due to over output. become able to.

[Effect] Therefore, it is possible to easily display an appropriate standby state according to the working device connected to the traveling machine, to perform the lifting operation of the working device irrespective of the type, and to connect to the traveling machine. Thus, it is possible to provide a lifting / lowering control structure of a working machine capable of easily obtaining an appropriate output rotation speed of the PTO shaft according to the working device to be operated and operating the working device satisfactorily.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an overall side view of a wireless remote control type working machine which is an example of a working machine, and FIG. 2 shows an overall plan view of the working machine. At the front of the body 1, a reaper 2, which is an example of the working device A,
It is configured to function as a mower by being connected via an elevating link mechanism 4 so as to be driven up and down by operation of a pair of left and right single-acting hydraulic cylinders 3.

The traveling body 1 is mounted on a body frame 5, an engine 6 mounted on the rear of the body frame 5, a cooling fan 7 and a radiator 8 provided behind the engine 6, and a front part of the body frame 5. Control device 9, body frame 5
And a left and right hydrostatic stepless transmission 11 that independently drives the left and right crawler-type traveling devices 10, respectively.

The reaping device 2 includes a flare mower type blade body 12 that cuts off grass grown on the ground by being rotated around a horizontal axis, a reaping case 13 that covers the blade body 12 from above, and a reaping case. 13, a hydraulic motor M1, a belt-type transmission mechanism 14 which is wrapped around the blade 12 and the hydraulic motor M1 so as to be capable of transmitting power, and a reaping case 1.
3 by a sled member 15 as a grounding body provided on each of the left and right sides, and a gauge wheel 16 as a grounding body provided on the front left and right sides of the cutting case 13, respectively.
The blade body 12 is configured to be hydraulically driven in which the blade body 12 is rotationally driven by the operation of the hydraulic motor M1.

The elevating link mechanism 4 is provided with a top link 17 extending vertically upward from the front upper part of the traveling body 1 so as to be able to swing vertically, and extending vertically upward and downward from the front lower part of the traveling body 1 so as to be able to swing vertically. A pair of left and right lower links 18, a substantially A-shaped hitch 19 pivotally connected to the front end of each of the links 17, 18, and a pair of left and right lift arms 20 disposed on the upper front of the traveling body 1. With the suspension links 21 laid over the corresponding lower links 18, respectively, the left and right lift arms 20 are vertically oscillated by the left and right hydraulic cylinders 3 by the expansion and contraction operation of the left and right hydraulic cylinders 3. It is configured as a hydraulic drive type.

That is, the working machine is configured to rotate the left and right crawler traveling devices 10 and to rotate the blades 12 in the reaper 2.
, The raising and lowering of the reaper 2 and the like are performed by hydraulic pressure.

As shown in FIG. 3, a hydraulic circuit of the working machine includes a hydraulic pump P1 for driving a working device for pumping hydraulic oil toward a hydraulic motor M1 mounted on the mowing device 2, and a left crawler type. Hydraulic motor M2 for driving traveling device 10
A hydraulic pump P2 for driving the left traveling device for pumping hydraulic oil toward the right side, a hydraulic pump P3 for driving the right traveling device for pumping hydraulic oil toward the hydraulic motor M3 for driving the right crawler traveling device 10, and cooling. A hydraulic pump P4 for driving a cooling fan for pumping hydraulic oil toward a hydraulic motor M4 for driving the fan 7, a hydraulic pump P5 for lifting and lowering a working device for pumping hydraulic oil toward the left and right hydraulic cylinders 3, and a working device drive Pump P6 for supplying working oil to a working device driving circulating oil passage R1 for circulating working oil between the hydraulic pump P1 and the hydraulic motor M1, and hydraulic pumps P2 and P3 for driving left and right traveling devices. And the corresponding hydraulic motors M2, M
3 is provided with a charge pump P7 for supplying hydraulic oil to the left and right circulating oil passages R2 and R3 for driving the traveling device for circulating the hydraulic oil between them. Reference numeral 22 in FIG. 3 denotes a connector with a check valve that removably connects an oil passage portion on the traveling machine body side and an oil passage portion on the work device side in the circulation oil passage R1 for driving the work device. Hydraulic pump P1 for driving the working device, hydraulic pump P for driving the left traveling device
2. A variable displacement pump is used for the hydraulic pump P3 for driving the right traveling device.

As shown in FIG. 4, the traveling hydraulic pump P2, hydraulic pump P3, and charge pump P7 are directly connected in series to the front of the engine 6 in the front-rear direction.
The engine 6 is driven by motive power output from a first output shaft 6 a provided in a front part of the engine 6. The working hydraulic pump P1 and the charge pump P6 are directly and serially connected to the rear of the engine 6 in a front-rear direction.
The motor is driven by power output from a second output shaft 6b disposed at the rear of the vehicle. The cooling hydraulic pump P4 and the elevating hydraulic pump P5 are directly and serially connected to the left side of the engine 6 in the front-rear direction, and the power output from the third output shaft 6c provided on the left side of the engine 6 is provided. It is designed to be driven by. That is, the engine 6 and each of the pumps P1 to P7 are unitized.
Thereby, the connection structure and the support structure are simplified. Incidentally, reference numeral 23 in FIG.
Anti-vibration rubber that supports the unitized engine 6 and each of the pumps P1 to P7.

As shown in FIG. 3, in the hydraulic pump P1 for driving the working device, the swash plate angle is changed by the operation of the servo valve 24 for switching the flow state of the hydraulic oil pumped from the charge pump P6. By changing the swash plate angle, the discharge amount and the circulation direction of the working oil to the hydraulic motor M1 for driving the working device are changed. That is, by controlling the operation of the servo valve 24, the output rotation speed of the hydraulic motor M1 can be adjusted according to the working device A connected to the traveling machine body 1, and the rotation direction of the working device A can be adjusted according to the working situation. It can be changed. The working device A connected to the traveling machine body 1 includes a grass collecting device (not shown) and a snow removing device (not shown) other than the mowing device 2.

Hydraulic pumps P2 for driving left and right traveling devices
In P3, the swash plate angle is changed by the operation of the servo valves 25 and 26 for switching the flow state of the hydraulic oil pressure-fed from the charge pump P7. The discharge amount and the circulation direction of the working oil to the hydraulic motors M2 and M3 for driving the traveling device are changed. That is, the left and right hydraulic pumps P2, P3 for driving the traveling device, the hydraulic motors M2, M
3. The left and right hydrostatic continuously variable transmission 11 is constituted by the circulating oil passages R2 and R3, the servo valves 25 and 26, and the charge pump P7, and controls the operation of the servo valves 25 and 26. Thus, the left and right crawler-type traveling devices 10 independently driven by the left and right hydrostatic continuously variable transmissions 11 can perform a stepless speed change operation and a forward / reverse switching operation. The hydraulic motors M2 and M3 for driving the left and right traveling devices are equipped with electromagnetic pickup type rotation speed detection sensors S1 and S2 for detecting their output rotation speeds and outputting them to the control device 9.

An oil passage R4 for connecting the cooling fan driving hydraulic pump P4 and the hydraulic motor M4 has a hydraulic pump P4
The electromagnetic switching valve 27 that changes the rotation direction of the hydraulic motor M4 by switching the flow direction of the hydraulic oil that is pressure-fed to the hydraulic motor M4 is provided, and the operation of the electromagnetic switching valve 27 is controlled. By rotating the hydraulic motor M4 in the forward direction, the driving state of the cooling fan 7 is changed to a cooling drive in which cooling air is taken in from the intake port 28 (see FIG. 1) at the rear of the body and flows toward the radiator 8 or the engine 6 or the like. The driving state of the cooling fan 7 can be changed by rotating the hydraulic motor M4 in the reverse direction so that dust or the like adhering to a dustproof net (not shown) of the radiator 8 can be switched to an intake port at the rear of the body. It is possible to switch to a backwashing drive state in which discharge from the machine 28 is performed outside the machine.

A flow priority valve 29, an electromagnetic unload valve 30, an electromagnetic proportional pressure control valve 31, and an electromagnetic check valve 32 are provided in an oil passage R5 connecting the hydraulic pump P5 for lifting and lowering the working device and the left and right hydraulic cylinders 3. , Is equipped. The surplus oil in the flow priority valve 29 is
An auxiliary operation device (not shown) connected to an auxiliary connector 33 with a check valve attached to a service port for extracting auxiliary power is supplied via an electromagnetic switching valve 34.

Each of the left and right crawler-type traveling devices 10 is provided with a negative brake 10A, and each of the negative brakes 10A is an electromagnetic switching valve for switching a flow state of hydraulic oil pumped from the charge pump P7 to each of the negative brakes 10A. A braking state in which a braking force is applied to the corresponding crawler-type traveling device 10 by biasing the coil spring 10a by controlling the operation of the coil spring 10a;
The operation mode is switched to a non-braking state in which the application of the braking force to the corresponding crawler-type traveling device 10 is prevented by the hydraulic oil from the charge pump P7.

A short-circuit oil passage R7 for short-circuiting the pair of control oil passages R6 connecting the hydraulic pump P1 for driving the working device and the servo valve 24 for changing the swash plate angle thereof is connected. In the short-circuit oil passage R7, a short-circuit electromagnetic switching valve for switching the short-circuit oil passage R7 between an open state (a state where the pair of control oil passages R6 is not short-circuited) and a closed state (a state where the pair of control oil passages R6 is short-circuited). 36 are interposed. In the left and right hydrostatic continuously variable transmission 11, a pair of control oil passages R8 each connecting hydraulic pumps P2 and P3 for driving the left and right traveling devices and servo valves 25 and 26 for changing their swash plate angles. ,
R9 includes a short-circuit oil passage R10 for short-circuiting them,
R11 are connected and their respective short-circuit oil passages R10,
R11 has a short circuit that switches between the short-circuit oil passages R10 and R11 between an open state (a state where the pair of control oil paths R8 and R9 are not short-circuited) and a closed state (a state where the pair of control oil paths R8 and R9 are short-circuited). Electromagnetic switching valves 37 and 38 are interposed.
In addition, each of the electromagnetic switching valves 36 to 38 for short-circuiting is of a negative type that is spring-biased to the short-circuit position side so as to show a short-circuit state of each of the short-circuit oil passages R9 to R11 when power is not supplied. I have.

As shown in FIG. 5, each of the servo valves 24-2
6 and the operation of the various solenoid valves 27, 30 to 32, 34 to 38 are controlled by the control device 9 including a microcomputer having a receiving function based on a control signal transmitted from the remote control device B having a transmitting function. It is controlled by operation. As shown in FIG. 6, the remote control device B
Includes a main switch 39, a neutral return type vehicle speed stick 40, a deceleration operation switch 41, and a deceleration adjustment dial 4.
2. A neutral return type steering stick 43, a neutral (elevation stop position) return type elevating switch 44, an elevating control mode changeover switch 45, an automatic mode setting switch 46, a working height setting dial 47, a forward rotation driving switch 48, A drive stop switch 49, a reverse drive switch 50, a work output adjustment dial 51, an engine stop switch 52, and the like are provided. As shown in FIG. 5, the control device 9 controls the drive of the left and right crawler-type traveling devices 10 based on a control signal from the remote control device B, and controls the elevation of the work device A. Lifting / lowering control means 9B, work control means 9C for controlling driving of work device A, and engine 6
An engine stop means 9D for stopping the engine is provided as a control program.

As shown in FIGS. 3 and 5 to 8, when the vehicle speed stick 40 is started to move from the neutral position to the forward area or the reverse area when the vehicle speed stick 40 is operated, first, the left and right stationary parts are simultaneously operated. By energizing the short-circuit electromagnetic switching valves 37 and 38 in the hydraulic continuously variable transmission 11 and switching the short-circuit oil passages R10 and R11 to the open state, the hydraulic pumps P2 and P2 are activated by the operation of the servo valves 25 and 26. P
The swash plate angle of No. 3 shows a runnable state in which a change operation from the neutral state is possible, and after a lapse of a predetermined time (for example, 0.1 second), the servo valves 25 and 26 are energized and each hydraulic pump P2 is turned on. , P3, the swash plate angle changing operation is started, and after a lapse of a predetermined time (for example, 0.3 seconds), the electromagnetic switching valve 35 for negative brake operation is energized to bring each negative brake 10A from the braking state to the non-braking state. The left and right crawler-type traveling devices 10 calculated from the target speed set by operating the vehicle speed stick 40 and the output rotation speeds of the hydraulic motors M2 and M3 detected by the rotation speed detection sensors S1 and S2, while switching to the state. The operation of each of the servo valves 25 and 26 is controlled so that the actual driving speed of the servo valves coincides with the actual driving speed. When the vehicle is ready to run at the start of traveling, if the vehicle speed stick 40 is operated from the neutral position to the forward or reverse range, the servo valves 25 and 26 are energized. , And the subsequent control operations are performed.

On the other hand, when the vehicle speed stick 40 is stopped when the vehicle speed stick 40 is operated from the forward movement area or the reverse movement area to the neutral position, the operation of the servo valves 25 and 26 is controlled simultaneously with the operation to control the operation of the hydraulic pumps P2 and P3. By changing the swash plate angle to the neutral side, the output rotation speeds of the hydraulic motors M2 and M3 are reduced, and time measurement is started, and within a predetermined time (for example, 2 seconds), the rotation speed detection sensors S1 and S2 are used. When the detected output rotational speeds of the hydraulic motors M2 and M3 become zero (the swash plate angles of the hydraulic pumps P2 and P3 are in a neutral state), the drive stopped state of the left and right crawler traveling devices 10 is changed to the present state. When it is determined that the brake has been released, the power supply to the electromagnetic switching valve 35 for negative brake operation is stopped to switch each negative brake 10A from the non-braking state to the braking state. When the operation to the forward area or backward area of the vehicle speed stick 40 is not performed in the predetermined time (e.g. 5 seconds), the electromagnetic switching valve for short 3
7 and 38, and the short-circuit oil passages R10 and R11 are stopped.
Is switched to the closed state, so that each servo valve 25,
26, the swash plate angle of each of the hydraulic pumps P2 and P3 is changed from the neutral state to an operation impossible state. On the other hand, as shown in FIG. 8, even though the swash plate angles of the hydraulic pumps P2 and P3 are being operated to the neutral side, the respective rotation speed detection sensors S1, The output rotation speed of each hydraulic motor M2, M3 detected by S2 is zero (each hydraulic pump P2, P
If the angle of the swash plate is not in the neutral state), it is determined that the aircraft has slipped down on an inclined ground or abnormality of each of the rotation speed detection sensors S1 and S2 has occurred, and each servo valve 2 is forcibly forced.
5, 26, electromagnetic switching valve 3 for negative brake operation
5, and stop the energization of the electromagnetic switching valves 37 and 38 for short-circuit, and execute a forced stop operation for simultaneously displaying the traveling impossible state and the braking state.

That is, at the start of traveling, each of the crawler-type traveling devices 1
Since the drive of 0 is started, the occurrence of a shock at the start of traveling can be prevented. Further, since the respective negative brakes 10A are switched from the braking state to the non-braking state after a lapse of a predetermined time from the start of driving of each crawler type traveling apparatus 10, the aircraft may slip down at the start of traveling on an uphill state. Can be prevented. On the other hand, when the traveling is stopped, the negative brake 10A is switched from the non-braking state to the braking state after the driving stopped state of each crawler type traveling device 10 appears, so that the occurrence of a shock when the traveling is stopped is reduced. It can be prevented. In addition, since the running disabled state appears after a lapse of a predetermined time after switching each of the negative brakes 10A to the braking state, when the running is resumed during the predetermined time, the re-drive of each crawler-type running device 10 is promptly performed. And a running stop state can be guaranteed after a predetermined time has elapsed. Further, regardless of the operation of the hydraulic pumps P2 and P3 toward the neutral side of the swash plate angle,
If the driving stop state of the left and right crawler type traveling devices 10 does not appear after a predetermined time has elapsed, the aircraft is forcibly stopped. Prevents slipping,
In addition, when the vehicle is stopped in other traveling states, it is possible to easily recognize the abnormality of the rotation speed detection sensors S1 and S2.

The traveling control means 9A includes a vehicle speed stick 40.
When the deceleration operation switch 41 is operated from the “OFF” position to the “ON” position in the driving state of the left and right crawler type traveling devices 10 by the operation of, the deceleration adjustment to the target speed set by the vehicle speed stick 40 is performed. Dial 4
A value obtained by multiplying the percentage set in Step 2 is set as a new target speed, and each servo valve 25 is adjusted so that the new target speed matches the actual drive speed of the left and right crawler traveling devices 10. , 26 by controlling the operation of the left and right crawler-type traveling devices 10. Conversely, during normal traveling in which the deceleration operation switch 41 is operated from the “ON” position to the “OFF” position, the target speed set by the vehicle speed stick 40 is set as a new target speed, and the new target speed and By controlling the operation of each of the servo valves 25 and 26 so that the actual driving speed of the left and right crawler-type traveling device 10 matches the actual driving speed, the normal traveling state of the left and right crawler-type traveling device 10 comes to appear. I have.

As shown in FIGS. 3, 5, 6, and 9,
In the driving state of the left and right crawler-type traveling devices 10 by operating the vehicle speed stick 40, the traveling control means 9A is configured to incline and incline the aircraft body in the left-right direction during straight traveling with the steering stick 43 at the neutral position. Tilt angle detection sensor S3 mounted on traveling body 1 to detect an angle
Each servo valve 2 based on the moving average of the detected values from
5 and 26 are controlled.

For example, as shown in FIG. 9, the traveling control means 9A is used for traveling straight on a flat ground where the moving average value of the inclination angle detected by the inclination angle detection sensor S3 is within ± 10 degrees or when traveling on an inclined ground. When the vehicle travels straight up and down along the inclination direction, the servo valves 25 and 26 are controlled so that the output rotation speeds of the left and right hydraulic motors M2 and M3 detected by the left and right rotation speed detection sensors S1 and S2 are synchronized. By changing the swash plate angles of the left and right hydraulic pumps P2 and P3 by controlling the operation, the left and right crawler type traveling devices 10 can be driven at a constant speed. As a result, it is possible to ensure the straightness of the working machine when traveling straight on flat ground or when traveling straight up and down along an inclined direction on an inclined ground.

On the other hand, when traveling on a contour line on a slope where the moving average value of the inclination angle detected by the inclination angle detection sensor S3 is larger than ± 10 degrees,
Due to the weight of the work machine, the force of lowering the work machine downward due to its own weight acts on the work machine, and the lowering force increases as the inclination angle of the sloping ground increases. As the moving average value of the inclination angle detected by the sensor S3 is larger, the output rotation speed of the hydraulic motor M2 (or M3) that drives the crawler type traveling device 10 located on the mountain side is the crawler type traveling device 10 located on the valley side. By controlling the operation of the servo valves 25 and 26 and changing the swash plate angles of the left and right hydraulic pumps P2 and P3 so that the output rotational speed of the hydraulic motor M3 (or M2) for driving the hydraulic pumps becomes lower than that of the hydraulic motor M3 (or M2). Left and right crawler type traveling device 10 capable of obtaining an appropriate lifting force in accordance with the pulling force acting on the work machine at the time of traveling on a contour line that changes according to the inclination angle of the sloped land
Unequal speed driving state.

In other words, when the vehicle travels on a contour line on a slope where the moving average value of the inclination angle detected by the inclination angle detection sensor S3 is larger than ± 10 degrees, the traveling control means 9A sets the moving average value of the inclination angle to be large. As the driving speed of the crawler-type traveling device 10 located on the valley side is made faster than the driving speed of the crawler-type traveling device 10 located on the hill side, the lifting force according to the pulling force that changes according to the inclination angle of the sloped ground is An appropriate tilting upward steering operation is automatically performed, and the work implement has an appropriate lifting force corresponding to the lowering force. Even without manual operation of B, it is possible to prevent the work machine from slipping down due to the lowering force, thereby facilitating the straight running of the work machine when traveling on a contour line. So that the it can be secured.

The traveling control means 9A changes the weight of the working machine depending on the type of the working device A connected to the front of the traveling machine body 1. Since the lowering force acting as a result increases as the weight of the work machine increases, the moving average value of the inclination angle detected by the inclination angle detection sensor S3 is ± 10%.
At the time of traveling on a contour line on a slope that is greater than the degree, the greater the weight of the working device A connected to the front portion of the traveling machine body 1, the greater the hydraulic motor M2 (or the hydraulic motor M2 that drives the crawler traveling device 10 located on the mountain side. The operation of each servo valve 25, 26 is controlled such that the output rotation speed of M3) becomes lower than the output rotation speed of the hydraulic motor M3 (or M2) that drives the crawler traveling device 10 located on the valley side. By changing the swash plate angles of the left and right hydraulic pumps P2 and P3, it is possible to obtain an appropriate lifting force according to the pulling force acting on the working machine at the time of traveling on a contour line, which varies according to the weight of the working machine. The non-uniform driving state of the crawler-type traveling device 10 is shown.

In other words, when traveling on a contour line on a slope where the moving average value of the inclination angle detected by the inclination angle detection sensor S3 is larger than ± 10 degrees, the traveling control means 9A is connected to the front part of the traveling body 1. The driving speed of the crawler-type traveling device 10 located on the valley side is made faster than the driving speed of the crawler-type traveling device 10 located on the mountain side as the weight of the working device A increases. The steering machine is also configured to automatically perform a steering operation to an appropriate inclination upward side that can obtain a lifting force according to the pulling force, so that the working machine has an appropriate lifting force corresponding to the pulling force. As a result, it is possible to prevent the work machine from slipping down due to its lowering force without manually operating the remote control device B. It has to be easily secured regardless of the type of the working device A coupled straightness of the working machine to the front of the vehicle body 1 (by weight). The travel control means 9
A is based on the operating position of a working device selection switch 67 (see FIGS. 1 and 5), which is a selection means provided on the traveling body 1 that is switched according to the type of the working device A connected to the traveling body 1. The type of the work device A is determined, whereby the work device A is used when traveling on a contour line on a slope where the moving average value of the tilt angle detected by the tilt angle detection sensor S3 is larger than ± 10 degrees. An appropriate unequal speed drive state of the right and left crawler traveling devices 10 in consideration of the weight of A can be realized. By the way, the weight of the working device A connected to the traveling machine 1 is about 350 kg for the reaper 2, about 250 kg for the grass collector, and about 400 kg for the snow removing device.

Further, the traveling control means 9A is a device in which the working device A is connected to the front portion of the traveling machine body 1, and a pulling force acting on the working machine at the time of traveling on a contour line due to its own weight is applied to the traveling device. Since the influence on the working machine due to the weight balance of the machine is different between the forward running and the reverse running, the moving average value of the tilt angle detected by the tilt angle detection sensor S3 becomes larger than ± 10 degrees. When traveling on a contour line on a slope, as shown in FIG. 10, a hydraulic motor M2 for driving the crawler type traveling device 10 located on the mountain side is used.
(Or M3) and the crawler traveling device 1 located on the valley side
The operation of each servo valve 25, 26 is controlled by controlling the operation of each servo valve 25, 26 so that the difference between the output rotation speeds of the hydraulic motors M3 (or M2) for driving 0 is changed to 時 に は of that during forward running. By changing the swash plate angles of the hydraulic pumps P2 and P3, an appropriate lifting in accordance with the pulling force acting on the working machine at the time of traveling on a contour line different between the forward running and the reverse running due to the weight balance of the working machine. The left and right crawler-type traveling devices 10 that can obtain a force appear in an unequal-speed driving state.

That is, when traveling on a contour line on a slope where the moving average value of the inclination angle detected by the inclination angle detection sensor S3 is larger than ± 10 degrees, the traveling control means 9A moves the vehicle to the valley side in accordance with the traveling direction. Crawler traveling device 10
And a crawler-type traveling device 10 located on the mountain side, the proper inclination to obtain a lifting force corresponding to a different pulling force between forward traveling and reverse traveling from the relation of the weight balance of the working machine that changes the speed difference. The steering operation to the upper side is also automatically performed, so that the work machine slips down with the front side in the traveling direction inclined downward and downward with the heavy side in front. When moving forward, the work machine has sufficient lifting force to prevent the work machine from slipping down while correcting the front side of the work machine in the forward direction, and conversely, the work is performed by leaving the heavy side behind. The work machine will have a lifting force that prevents only the work machine from slipping down during reverse travel, in which the machine will slip down with the rear side of the traveling direction inclined downward. Therefore, even if the remote control device B is not manually operated, it is possible to prevent the work machine from slipping down due to the pulling-down force that changes depending on the traveling direction. It can be easily secured regardless of the direction of the aircraft.

Further, when controlling the driving speeds of the left and right crawler type traveling devices 10 as described above, the traveling control means 9A outputs the hydraulic motors M2, Since the control operation is performed based on the detection values from the rotation speed detection sensors S1 and S2 that detect the output rotation speed of the M3, each hydraulic pressure in the left and right hydrostatic continuously variable transmission 11 is controlled. The operation of the pumps P2, P3 and the hydraulic motors M2, M3 is not affected by variations in the performance, changes in the oil temperature, and the like.

As shown in FIGS. 3, 5 and 6, when the left and right crawler-type traveling devices 10 are driven by operating the vehicle speed stick 40, the traveling control means 9A controls the steering stick 43 within the pivot mode area. At the time of a left turning operation in the left steering region, the operation of the servo valve 25 is controlled so that the swash plate angle of the hydraulic pump P2 for driving the left traveling device is in a neutral state, and the left crawler-type traveling device 1 is controlled.
A left pivot turning traveling state in which the driving of the zero is stopped is brought out. Conversely, when the steering stick 43 is operated to the right steering area in the pivot mode area during the right turning operation, the servo valve 26 is set so that the swash plate angle of the hydraulic pump P3 for driving the right driving apparatus is in the neutral state. By controlling the operation, a right pivot turning traveling state in which the driving of the right crawler traveling device 10 is stopped is brought out.

When the left and right crawler-type traveling devices 10 are driven by operating the vehicle speed stick 40 and the left steering region is operated in the spin mode region when the steering stick 43 is operated in the left steering region, the left traveling device driving device is used. So that the swash plate angle of the hydraulic pump P2 is in a constant-speed reverse rotation state (a state in which the hydraulic motor M2 for driving the left traveling device outputs the same rotational speed as the hydraulic motor M3 for driving the right traveling device in the reverse direction). By controlling the operation of the valve 25, a left spin turning traveling state in which the left crawler traveling device 10 is driven to rotate in reverse at a constant speed with respect to the right crawler traveling device 10 appears. Conversely, when the steering stick 43 is operated in the right steering area in the spin mode area in the right turning area, the swash plate angle of the hydraulic pump P3 for driving the right traveling apparatus is in a constant reverse rotation state (for driving the right traveling apparatus). (The state in which the hydraulic motor M3 outputs the same number of revolutions as the hydraulic motor M2 for driving the left traveling device in the reverse direction) by controlling the operation of the servo valve 26 to move the right crawler traveling device 10 to the left. A left-spin turning traveling state in which the crawler traveling device 10 is driven to rotate in the reverse direction at a constant speed appears.

As shown in FIGS. 3, 5 and 6, the elevation control means 9B controls the operation of the electromagnetic unload valve 30, the electromagnetic proportional pressure control valve 31, and the electromagnetic check valve 32 to thereby control the traveling body. Height detection sensor S mounted on 1
4, the height position of the mowing device 2 (an example of the working device A) with respect to the traveling machine body 1 is set by the working height setting dial 47 as a height setting device. Position control means 9Ba for controlling the operation of the left and right hydraulic cylinders 3 so as to match the height position, and floating for lowering the pressure in the left and right hydraulic cylinders 3 to a preset lower set value at the time of the descending operation. After supplying hydraulic oil to the hydraulic cylinder 3 during the operation time during the elevating operation during the elevating operation, the pressure in the hydraulic circuit R5a for the hydraulic cylinder 3 is adjusted to a preset high side set value. The lifting control mode changeover switch 45 comprises a floating control means 9Bb for displaying a standby state for maintaining the state.
Is operated to switch the elevation control mode between the position control mode by the position control means 9Ba and the floating control mode by the floating control means 9Bb. The height detection sensor S4
Is for detecting the height position of the reaper 2 with respect to the traveling machine body 1 from the vertical swing angle of the lift arm 20.

More specifically, the position control means 9Ba
When the position control mode is selected by operating the elevation control mode changeover switch 45, the target height position of the reaper 2 with respect to the traveling machine 1 set by the work height setting dial 47 and the height detection sensor By comparing the current height position of the reaper 2 with respect to the traveling body 1 detected by S4, if the height position of the reaper 2 is lower than the target height position, the elevation switch 44 is operated to the up side. In this case, the operation of the electromagnetic unload valve 30, the electromagnetic proportional pressure control valve 31, and the electromagnetic check valve 32 is controlled based on the operation position of the working height setting dial 47, so that the reaper 2 is moved to the working height. Setting dial 47
The right and left hydraulic cylinders 3 are extended so as to be positioned at the target height position of the mowing device 2 with respect to the traveling machine body 1 set by the above. Conversely, when the up / down switch 44 is operated to the lower side, the operation of the electromagnetic unload valve 30, the electromagnetic proportional pressure control valve 31, and the electromagnetic check valve 32 is controlled based on the operation, so that the operation is controlled. The left and right hydraulic cylinders 3 are shortened only during the time. On the other hand, when the height switch of the reaper 2 is higher than the target height position and the elevating switch 44 is operated to the lower side, the working height setting dial 47 is used.
The operation of the electromagnetic unload valve 30, the electromagnetic proportional pressure control valve 31, and the electromagnetic check valve 32 is controlled based on the operating position of the cutting device 2, so that the cutting device 2 cuts the traveling body 1 set by the working height setting dial 47. The left and right hydraulic cylinders 3 are shortened so as to be located at the target height position of the device 2. Conversely, lifting switch 4
When the valve 4 is operated on the ascending side, the operation of the electromagnetic unload valve 30, the electromagnetic proportional pressure control valve 31, and the electromagnetic check valve 32 is controlled based on the operation, so that the left and right are controlled only during the operation time. The hydraulic cylinder 3 is extended.

That is, in the position control mode, the position control means 9Ba moves the reaper 2 based on the operation of the elevating switch 44 to the working height setting dial 4.
In the work place where many obstacles such as concrete pieces and stones are scattered, the work height setting dial 47 is used to set the appropriate position of the reaper 2 at the target height position set by 7. With a simple operation of setting the target height position and operating the elevating switch 44, the mowing operation is performed in a state where the mowing device 2 is floated at a height position at which contact with an obstacle can be avoided. Can easily appear, so that the mowing device 2 comes into contact with obstacles such as concrete pieces and stones at the time of cutting work in a work place where many obstacles such as concrete pieces and stones are scattered. It is possible to easily prevent such inconveniences as those obstacles being bounced off or the reaper 2 being damaged.

On the other hand, the floating control means 9Bb
In a state in which the floating control mode is selected by operating the lifting / lowering control mode changeover switch 45, the open state of the electromagnetic unload valve 30 with respect to the hydraulic cylinder 3 and the closed state of the electromagnetic check valve 32 appear as shown in FIG. At the same time, the operation of the electromagnetic proportional pressure control valve 31 is controlled, and the pressure in the hydraulic circuit R5a from the hydraulic pump P5 for lifting and lowering the working device to the electromagnetic check valve 32 is preset so as to be balanced with the weight of the reaper 2. A standby state in which the pressure is raised to a standby pressure (for example, 2.5 MP) which is a set value on the higher side is displayed, whereby the open state of the electromagnetic check valve 32 is displayed during the raising operation. As a result, the mowing device 2 rises rapidly or the mowing device 2 once descends and then rises. With the revealing of the open state of the click valve 32,
It is possible to prevent such a problem that the reaper 2 suddenly descends or the reaper 2 rises and then descends.

When the automatic mode setting switch 46 is operated (ON) in this state, the floating control means 9Bb causes the electromagnetic unload valve 3 to operate based on the operation.
Open state of the hydraulic cylinder 3 and the electromagnetic check valve 3
2 and the electromagnetic proportional pressure control valve 3
1 is controlled to lower the pressures in the left and right hydraulic cylinders 3 to a preset lower side set value (for example, 1.0 MP), whereby the reaper 2 is controlled.
, A part of the weight is left on the ground, and the ground follows the unevenness of the ground so as to appear in a floating state. That is, in a work place where obstacles such as concrete pieces and stones are scarcely scattered, this floating state is caused to appear, so that the reaper 2 can be brought into contact with the gauge wheel 16 along the unevenness of the ground in a predetermined manner. Since the cutting device 2 can be stably positioned at the ground height position, uncut grasses caused by the cutting device 2 being unnecessarily separated from the ground, soil cutting caused by the cutting device 2 coming into contact with the ground, It is possible to avoid abrasion of the mowing device 2 and the like, so that it is possible to perform a good mowing operation in which grass growing on the ground can be trimmed to a predetermined ground height, and to improve the durability of the mowing device 2. Can be planned.

The floating state can be released by operating the lift switch 44. When the release operation is performed, the floating control means 9Bb controls the electromagnetic proportionality based on the operation direction of the lift switch 44. The operation of the pressure control valve 31 is controlled to supply and discharge the hydraulic oil to and from the hydraulic cylinder 3, and the closed state of the electromagnetic check valve 32 appears after the operation of the elevating switch 44 (after returning to the elevating stop position). Finally, the operation of the electromagnetic proportional pressure control valve 31 is controlled so that the pressure in the hydraulic circuit R5a for the hydraulic cylinder 3 becomes the above-described standby pressure (higher set value).

For example, in the case where the up / down switch 44 is operated to the up side, if the operation is completed before the pressure in the hydraulic circuit R5a reaches the standby pressure, as shown by the solid line in FIG. Is
At the end of the operation, the closed state of the electromagnetic check valve 32 appears (the electromagnetic unload valve 30 remains open with respect to the hydraulic cylinder 3), and the operation of the electromagnetic proportional pressure control valve 31 is controlled. Until the pressure in the hydraulic circuit R5a reaches the above-described standby pressure (higher set value), the operating oil is supplied toward the hydraulic cylinder 3 to cause the standby state to appear, and the standby state is maintained. . When the operation of the raising / lowering switch 44 to the rising side is continued even after the pressure in the hydraulic circuit R5a reaches the standby pressure, the floating control means 9Bb, as shown by the broken line in FIG. While the operation of the switch 44 on the ascending side is continued, the electromagnetic check valve 32 is kept open and the operation of the electromagnetic proportional pressure control valve 31 is controlled to supply hydraulic oil to the hydraulic cylinder 3 for cutting. The apparatus 2 is raised, and as the operation is completed, the electromagnetic check valve 32 is brought into a closed state to cut off the supply of hydraulic oil to the hydraulic cylinder 3 so that the reaper 2 is moved up and down by the elevating switch 44 at that time. And the operation of the electromagnetic proportional pressure control valve 31 is controlled so that the pressure in the hydraulic circuit R5a is reduced to the aforementioned standby pressure (higher set value). Current issues a standby state by discharging the hydraulic oil in the hydraulic circuit R5a, is adapted to maintain the standby state.

On the other hand, when the up / down switch 44 is operated to the lower side, as shown by the solid line in FIG. 11, the floating control means 9Bb operates while the operation of the up / down switch 44 to the lower side is continued. While maintaining the electromagnetic check valve 32 in the open state and controlling the operation of the electromagnetic proportional pressure control valve 31, the hydraulic oil is discharged from the hydraulic cylinder 3 to increase the ground pressure of the reaper 2, and the operation ends. As a result, the closed state of the electromagnetic check valve 32 appears and the discharge of the hydraulic oil from the hydraulic cylinder 3 is cut off, so that the reaper 2 is grounded to the ground at a desired ground pressure by operating the elevation switch 44 at that time. At the same time, the operation of the electromagnetic proportional pressure control valve 31 is controlled to increase the pressure in the hydraulic circuit R5a to the above-described standby pressure (higher set value) by using the hydraulic oil. And supplied toward the 3 current issued a standby state, so as to maintain its stand-by state. Incidentally, in the present embodiment, as shown in FIG. 11, the lowest value of the pressure in the hydraulic cylinder 3 that can appear by operating the elevating switch 44 is set to 0.2MP.

The electromagnetic check valve 32 is of a negative type which is spring-biased to a stop position for preventing the flow of hydraulic oil. The oil passage is shut off to prevent the reaper 2 from dropping sharply.

As shown in FIG. 5, in the floating control mode, the working height setting dial 47 functions as a pressure setting device 53 which is a setting device for changing the setting value of the lower side. By operating the pressure setting device 53, the set value on the lower side can be changed from the maximum value (2.5MP = 100%) which is the standby pressure to the minimum value (0.2MP = 0%). It has become. Thereby, when the work place is soft, the pressure setter 53 is operated by operating the pressure setter 53 so that the lower set value approaches the standby pressure as the work place becomes softer according to the degree. By increasing the pressure, it is possible to reduce the weight ratio of the reaper 2 on the ground when mowing in the floating state, so that the sled member 15 and the gauge wheel 1 serving as the ground contact body during mowing work.
6 can be prevented from sinking into the ground, thereby avoiding the occurrence of earth-cutting due to it. Also, by operating the pressure setting device 53 in accordance with the type and amount of grass to be cut, the weight (ground pressure) of the cutting device 2 applied to the ground can be adjusted. It is also possible to prevent the inconvenience of unnecessarily high mowing due to the ascent due to the resistance of the surface. Furthermore, since the working height setting dial 47 in the position control mode is made to function as the pressure setting device 53 in the floating control mode, the configuration is simplified and compared to the case where a dedicated setting device is provided. The production cost can be reduced.

As described above, as the working device A connected to the traveling machine 1, there are a grass collecting device and a snow removing device in addition to the mowing device 2, and the working devices A having different weights (the cutting device). 2 is about 350 kg, grass harvester is about 2
50kg, snow removal device is about 400kg)
The floating control means 9Bb determines the type of the work device A in the same manner as the travel control means 9A based on the operation position of the work device selection switch 67, and based on the determination, determines whether the type of the work device A is within the hydraulic circuit R5a for the hydraulic cylinder 3. So that the pressure and the weight of the connected working device A are balanced,
Change the preset standby pressure, which is a preset value on the higher side (for example, 2.0MP for a grass collector weighing about 250kg, or 2.0MP for a snowplow weighing about 400kg). Is changed to 3.0MP), and the maximum value of the lower set value set by the operation of the pressure setter 53 is changed to the standby pressure value of the working device A to be connected (for example, 2.0M for grass equipment
P, or 3.0MP if the device is a snow removal device). Thereby, irrespective of the type of the working device A connected to the traveling machine body 1, the reaping device 2 rises rapidly at the time of the lifting operation of the working device A, or the reaping device 2 once descends and then rises. It is possible to prevent inconveniences and inconveniences such as the mowing device 2 suddenly lowering during the lowering operation of the working device A or the mowing device 2 once rising and then lowering, and can be prevented according to the situation of the work site. Appropriate floating state can be realized.

The floating control means 9Bb calculates the pressure value from the amount of control current for the electromagnetic proportional pressure control valve 31.

The floating control means 9Bb, based on the discrimination of the type of the working device A, outputs a PTO shaft 54 for driving the working device A (the output shaft of the hydraulic motor M1 for driving the working device mounted on each working device A). The work drive control for changing the setting of the output rotation speed is performed. Specifically, the floating control means 9Bb sets the setting range of the output rotation speed of the PTO shaft 54 that can be adjusted by the work output adjustment dial 51 to the original maximum output when the work device A is the reaper 2. In the case of a grass-collecting device, the range is changed to 20 to 65% with respect to the original maximum output, and in the case of a snow removal device, the range is changed to 80 to 100%. In the range of 40 to 100%. That is, the floating control means 9Bb is configured to regulate the minimum output and the maximum output of the PTO shaft 54 according to the type of the working device A,
As a result, it is possible to prevent the occurrence of work failure due to insufficient output and the damage of the work apparatus A due to output excess. The work drive control by the floating control means 9Bb is also executed in the position control mode. Further, before the main switch 39 of the remote control device B is turned "ON", the floating control means 9Bb operates the raising / lowering switch 44 upward or downward, or turns the automatic mode setting switch 46 "ON". When the operation is performed, the control operation based on the operation of the elevation switch 44 and the automatic mode setting switch 46 is not executed until the neutral operation of the elevation switch 44 or the “OFF” operation of the automatic mode setting switch 46 is confirmed. This is how
It is possible to prevent the working device A from suddenly moving up and down unexpectedly with the "ON" operation of the main switch 39 of the remote control device B.

The work control means 9C controls the operation of the servo valve 24 based on the operation of the normal rotation drive switch 48 provided in the remote control device B, so that the swash plate angle of the hydraulic pump P1 for driving the work device is controlled. Is changed to cause the hydraulic motor M1 for driving the working device to rotate in the normal direction, so that the normal rotation driving state of the reaper 2 appears. Further, by controlling the operation of the servo valve 24 based on the operation of the reverse rotation drive switch 50, the swash plate angle of the hydraulic pump P1 is changed and the hydraulic motor M1 is reversely operated.
The reversing drive state of the reaper 2 is made to appear. Further, by controlling the operation of the servo valve 24 based on the operation of the drive stop switch 49, the hydraulic pump P1
By changing the swash plate angle to the neutral state and stopping the operation of the hydraulic motor M1, the drive stop state of the reaper 2 is made to appear.

The engine stopping means 9D includes a remote control device B
The engine 6 is stopped based on the operation of the engine stop switch 52 provided on the vehicle. Further, the operation of the operation lever 55 (see FIG. 1) provided on the left side of the traveling body 1 forcibly shuts off the fuel supply to the engine 6, thereby making it possible to stop the engine 6 in an emergency. ing. Incidentally, the engine 6 can be started by operating a key switch 56 (see FIG. 1) provided on the left side of the traveling machine body 1.

As shown in FIG. 2, the traveling body 1 and the mowing device 2 are designed so that the cutting width of the mowing device 2 is maximized in terms of working efficiency, and the traveling body 1 is motivated by the stability of the aircraft. The maximum dimensions that can be accommodated within the width of the carrier to ensure that each can fit within the width of the carrier when transported by a truck such as a truck while keeping the tread dimensions as large as possible. The respective width dimensions are set so as to be substantially the same width. As a result, while improving work efficiency and stability of the aircraft,
The traveling body 1 or the reaper 2 can be prevented from coming into contact with the traveling body 1 or the other part of the reaper 2 during transportation due to the protruding portion of the reaper.

As shown in FIG. 12, a hitch 19 connects a hook metal 19A disposed at the upper left and right center and an engagement metal 19B disposed at the lower left and right ends by a substantially equilateral triangular frame 19C. It is constituted by doing. The left and right engagement fittings 19B include a concave portion 19a having an open front side, and a hook-shaped engaging piece 19b and an engaging piece 19 which are provided to be able to swing up and down around a horizontal axis in the concave portion 19a.
An urging spring (not shown) for urging the engaging piece 19b to swing upward so as to close the front of the concave portion 19a is formed. The downward swing operation of each of the engagement pieces 19b is performed by applying pressure from the front to each of the engagement pieces 19b, or by operating the operation lever 57 which is swingably supported at the center of the frame 19C around the horizontal axis. It can be done with. On the other hand, the cutting case 13 of the cutting device 2 includes
A first connecting portion 13A is provided at the center in the left and right direction, and a second connecting portion 13B is provided at a position displaced rightward from the first connecting portion 13A by a predetermined amount (for example, 200 mm). Each of the connecting portions 13A and 13B includes a first connecting pin 13b provided at an upper end of a pair of support frames 13a extending upward from the reaping case 13, and a pair of first and second left and right lower portions of the support frame 13a. The second connection pin 13c is arranged in each case.

With the above arrangement, the traveling machine 1 is advanced toward the reaping device 2 with the hitch 19 lowered, so that the hook metal 19A of the hitch 19 is connected to the first connecting portion 13A or the second connecting portion 13A of the reaping device 2. The hitch 19 is positioned below the first connecting pin 13b of the connecting portion 13B.
Is raised, first, the first connecting pin 13 of the reaper 2
b is engaged with the hook fitting 19A of the hitch 19, and then the mowing device 2 swings around the first connecting pin 13b to the hitch 19 side and presses against the hitch 19 from the front side, whereby the mowing device The second second connection pin 13c is engaged with the engagement fitting 19B of the hitch 19, so that the connection of the reaper 2 to the traveling body 1 is completed. When the hitch 19 is lowered in a state where the engagement piece 19b of each of the engagement fittings 19B is moved downward by the operation of the operation lever 57, first, the second connecting pin 13c of the reaper 2 is engaged with the engagement metal of the hitch 19. From the tool 19B, and then the hitch 19
Of the first connecting pin 13b of the reaper 2
And the removal of the reaper 2 from the traveling body 1 is completed. In other words, with a simple configuration in which the first connecting portion 13A and the second connecting portion 13B are simply provided in the cutting case 13 of the mowing device 2, it is possible to easily attach and detach the mowing device 2 to and from the traveling body 1 and change the connecting position. It has become.

When the hitch 19 is connected to the first connecting portion 13A of the mowing device 2, as shown by a solid line in FIG.
The mowing device 2 is positioned at a non-offset position where the left and right side edges of the traveling body 1 and the left and right side edges of the mowing device 2 substantially coincide with each other with respect to the traveling machine body 1, so that a normal mowing operation is performed. When the vehicle is transported by a truck or a carrier, the non-offset connection state is exposed so that the cutting operation can be performed in a stable state in which the left-right balance of the machine is substantially balanced, and the traveling body 1 and the reaper 2 can be transported by the carrier. It is designed to fit within the width of the carrier. On the other hand, when the hitch 19 is connected to the second connecting portion 13B of the reaper 2,
As shown by a dashed line in FIG. 2, the reaper 2 is positioned at an offset position where the left end of the reaper 2 projects from the left end of the traveling body 1 with respect to the traveling body 1. When the mowing work is performed on the side of the edge or the shoulder at the boundary with the slope (cliff), the traveling body 1 is moved away from the slope at the top of the embankment or the shoulder by displaying this offset connection state. In this state, it is possible to cut grass growing on the boundary side with the slope. Moreover, in the offset connection state, the right end side of the reaper 2 which is relatively heavy due to the provision of the hydraulic motor M1 for driving the reaper is positioned within the width of the traveling machine body 1 and is located closer to the right end side than the right end side. Since the relatively light left end protrudes from the left end of the traveling body 1, the left-right balance of the body can be balanced, so that the grass growing on the boundary side with the slope can be cut off. It can be performed in a stable state where the right and left balance of the aircraft is balanced.

As shown in FIG. 13 and FIG. 14, the engine frame 5A is positioned above the track frame 5B so that a space s is formed inside the hydraulic motors M2 and M3 for driving the traveling device. The maintenance space for the hydraulic motors M2 and M3 and the rotation speed detection sensors S1 and S2 can be ensured while keeping the machine center of gravity as low as possible. It is designed to improve the performance. As shown in FIGS. 1 and 14, the left and right track frames 5B have crawler-type traveling devices 10 respectively.
And the crawler-type traveling device 1
A pair of front and rear hanging brackets 5a that can be switched between a retracted position and a retracted position stored within a width of 0 are connected by pins.
In the event of a failure, the hanging bracket 5a is switched to the operating position to engage a hook such as a crane,
It can be suspended and transported by a crane or the like. In addition, instead of the hanging metal fittings 5a, a protection frame (not shown) extending over the right and left track frames 5B is connected, so that breakage at the time of falling can be suppressed. Note that the hanging bracket 5a can be held in the operating position and the retracted position by the action of a detent mechanism (not shown).

As shown in FIGS. 1 and 2, an arch-shaped support frame 5C is erected at a substantially intermediate position between the front and rear of the traveling body 1, and front and rear bonnets 58 and 59 are mounted on the support frame 5C. It is designed to be vertically swingable. That is, by raising and swinging the hood 58 on the front side to open the front side of the traveling body 1, the control device 9 disposed at the front of the traveling body 1, the hydraulic pumps P2 and P3 for driving the traveling apparatus, The maintenance of the charge pump P7 and the like can be easily performed from the front side of the traveling machine body 1. Also, by raising and swinging the rear hood 59 to open the rear side of the traveling body 1,
Maintenance of the engine 6, the hydraulic pump P4 for driving the cooling fan, and the hydraulic pump P5 for lifting and lowering the working device, etc., arranged at the rear of the traveling body 1 can be easily performed from the rear side of the traveling body 1. .

As shown in FIG. 15, a mounting table 61 is mounted on the upper portion of the support frame 5C via two anti-vibration rubbers 60 on the left and right sides.
The yellow and green rotating lights 62, 63, 64 are provided with vibration-proof rubber 65.
Is placed via. That is, each of the rotating lights 62, 6
By adopting a double anti-vibration support structure for 3, 64, the durability of each of the rotary lights 62, 63, 64 is improved. The red rotating light 62 is turned on when an abnormality such as reception occurs, thereby alerting the operator of the abnormality. Yellow rotating light 63
Is illuminated when the inclination angle detected by the inclination angle detection sensor S3 exceeds a predetermined value to warn the operator that the aircraft may fall down. The green rotating light 64 is turned on when the reaper 2 is being driven, so that the driver can grasp the driving state of the reaper 2. That is, since the rotating lights 62, 63, and 64 of three colors are provided and the rotating lights 62, 63, and 64 to be turned on are changed according to the contents of the warning, the warning contents can be easily and accurately provided to the pilot. It can be recognized. A receiving antenna 66 is mounted on the upper left side of the mounting table 61 so as to be able to swing back and forth and to maintain its posture. By switching the antenna 66 from the rearwardly inclined posture during use (the state shown by the solid line in FIG. 1) to the upright posture (the state shown by the one-dot chain line in FIG. 1), it is possible to avoid the inconvenience that the receiving antenna 66 is in the way. It has become.

[Another Embodiment] Another embodiment will be described below. The work machine may be a grass collector configured by connecting a weeding device to the traveling body 1 or a snow blower configured by connecting a snow removing device to the traveling body 1. The mowing device 2 may be a blade mower type, a reel mower type, or the like, in addition to a flare mower type. The selection means 67 may be provided in the remote control device B.

[Brief description of the drawings]

FIG. 1 is an overall side view of a mower.

FIG. 2 is an overall plan view of the mower.

FIG. 3 is a hydraulic circuit diagram of the mower.

FIG. 4 is a side view showing a state where the engine and each pump are unitized.

FIG. 5 is a block diagram showing a control configuration of the mower.

FIG. 6 is a perspective view showing the configuration of a remote control device.

FIG. 7 is a time chart showing a control operation of the traveling control means at the time of starting traveling and at the time of stopping traveling.

FIG. 8 is a time chart showing a forced stop operation when the travel control means stops traveling.

FIG. 9 is a graph showing the speed difference between the left and right traveling devices according to the weight of the working device in the control operation of the traveling control means based on the detection from the inclination angle detection sensor.

FIG. 10 is a graph showing a speed difference between left and right traveling devices according to a traveling direction in a control operation of traveling control means based on detection from an inclination angle detection sensor.

FIG. 11 is a time chart showing the control operation of the floating control means.

FIG. 12 is a perspective view showing a connection structure between the traveling body and the reaper.

FIG. 13 is a side view showing a frame structure of the traveling body.

FIG. 14 is a longitudinal rear view showing the frame structure of the traveling body.

FIG. 15 is a longitudinal sectional front view showing a supporting structure for a rotating light and a receiving antenna.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Traveling body 3 Hydraulic cylinder 4 Elevating link mechanism 9Bb Floating control means 53 Setting device 54 PTO shaft 67 Selection means A Working device R5a Hydraulic circuit

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazunari Abe 2310, Oda, Yamada, Kurosaki-cho, Nishikanbara-gun, Niigata Pref. 64, Ishizukitamachi, Kubota Sakai Factory Co., Ltd. (72) Inventor Nakamura, No. 64, Ishizukitamachi, Sakai City, Osaka Prefecture Inside, Kubota Sakai Factory Co., Ltd. Kubota Sakai Works

Claims (3)

[Claims] 1. A lifting / lowering control structure for a working machine, wherein a working device is connected to a traveling machine body via a lifting / lowering link mechanism so as to be driven up and down by operation of a hydraulic cylinder. In a floating state in which the pressure of the hydraulic cylinder is reduced to a preset low-side set value, and after supplying and discharging hydraulic oil to and from the hydraulic cylinder only during the operation time during the elevating operation, the hydraulic circuit in the hydraulic circuit for the hydraulic cylinder A lifting and lowering control structure of a working machine, provided with a floating control means for displaying a standby state in which the pressure is adjusted to a preset high-side set value and the state is maintained. 2. The lifting and lowering control structure for a working machine according to claim 1, further comprising a setting device for changing the setting value of the lower side. 3. A selection device for selecting a type of the working device, wherein the floating control device changes the setting value of the higher side based on the selection of the selecting device, The lifting / lowering control structure for a working machine according to claim 2, wherein the output rotation speed of the driven PTO shaft is configured to be changed.