JP2000272532A - Running operating device for crawler type running machine body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve workability by performing switching action of a control valve by a pilot pressure output from a plurality of front/rear right/left pilot valves according to operation of a single joy stick type operating lever operable even in any direction of the front/rear right/left from a neutral position. SOLUTION: Front/rear right/left four pilot values 15, 16, 17, 18 are assembled in a pilot valve unit 14, each pilot valve 15, 16, 17, 18 is constituted by a variable type pressure reducing valve. These pilot valves 15, 16, 17, 18 output a pilot pressure based on operation of a single running operating lever. In the case that operation of a work device is desired during running, it is only required that while operating the running operating lever by one hand, an operating lever and operating pedal for the work device are operated by the other hand and foot. In this way, workability can be improved without busily engaging both hands and both feet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a traveling operating device for a crawler type traveling machine such as a hydraulic shovel.

[0002]

2. Description of the Related Art Generally, a crawler-type traveling machine such as a hydraulic excavator is provided with a pair of left and right crawler-type traveling units and a traveling operation device for operating these traveling units. Conventionally, the device is provided with a left traveling operating tool for driving and stopping the left traveling unit, and a right traveling operating tool for driving and stopping the right traveling unit. For example, when the traveling body is made to move straight forward or backward, both the left and right traveling operation tools are simultaneously operated in the same direction, and the vehicle is turned left and right or spin-turned (the left and right traveling devices are driven in opposite directions). In the case where the direction change is performed, the operation amounts of the left and right traveling operation tools are changed or operated in opposite directions.

[0003]

The conventional left and right traveling operating tools include an operating lever, an operating pedal, or an operating lever and an operating pedal arranged side by side. However, since the left and right operation levers or operation pedals must be operated for traveling as described above, both hands or both feet must be operated. For this reason, when it is desired to operate the working unit while traveling, there is a problem that the number of working unit operating tools that can be operated simultaneously because both hands or both feet are occupied is limited, resulting in poor workability. Here, there was a problem to be solved by the present invention. Furthermore, as a traveling operation tool,
There is also a problem to be solved that requires a pair of left and right dedicated operation tools, which increases the number of parts and hinders cost reduction.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and has been made for the purpose of solving these problems.
In a crawler-type traveling body configured to move forward and backward based on the driving of the corresponding left and right hydraulic motors, the left and right control valves for controlling the hydraulic oil supply of the left and right hydraulic motors are driven forward by the hydraulic motors. The switching operation of the control valve is performed by a single joystick that can be operated in any of the front, rear, left, and right directions from the neutral position when switching to the forward side where the pressure oil is supplied to be driven and the reverse side where the pressure oil is supplied to be driven backward. The control is performed by pilot pressures output from four pilot valves, front, rear, left and right, in accordance with the operation of the mold operation lever. In this way, the left and right traveling parts can be operated with a single joystick-type operation lever, and both hands and feet are used as in a conventional traveling operation using a pair of left and right traveling operation tools. Is not blocked, and the workability is improved. In this device, the front pilot valve outputs pilot pressure for switching both left and right control valves to the forward side, the rear pilot valve outputs pilot pressure for switching both left and right control valves to the reverse side, and the left pilot valve Outputs the pilot pressure for switching the right control valve to the forward side and the left control valve to the reverse side.The right pilot valve outputs the pilot pressure for switching the left control valve to the forward side and the right control valve to the reverse side. With this configuration, various traveling operations can be performed with one joystick-type operation lever. Furthermore, by disposing a shuttle valve that selects the high pressure side of the pilot pressure output from each pilot valve and outputs it to the control valve in the pilot oil passage from the front and rear left and right pilot valves to the left and right control valves,
The pilot pressure corresponding to the operation of the operation lever can be output to the control valve.

[0005]

Next, an embodiment of the present invention will be described with reference to the drawings. In the drawings, reference numeral 1 denotes a hydraulic excavator, and the hydraulic excavator 1 includes a lower traveling body 2, an upper revolving body 3 that is rotatably supported above the lower traveling body 2,
The basic configuration such as the configuration of the working unit 4 and the like attached to the upper revolving unit 3 and the lower traveling unit 2 is the same as the conventional one.

The lower traveling body 2 has a pair of left and right traveling parts 5, 6 of a crawler type. The left and right traveling parts 5, 6 are provided on the traveling parts 5, 6 respectively. The hydraulic oil supply circuits for the left and right hydraulic motors 7 and 8 are configured to move forward, reverse, and stop based on the drive of the hydraulic motors 7 and 8, respectively. 9 is a main pump, 10 is a pilot pump, 1
1 is an oil tank, 12 and 13 are left and right control valves.

The left and right control valves 12, 13
Controls the supply of hydraulic oil to the left and right hydraulic motors 7 and 8, respectively. However, since the control valves are the same as the right and left, the control valve 12 on the left side will be described. It is constituted by a three-position switching valve having a side pilot port 12b.
When the pilot pressure is not input to both pilot ports 12a and 12b, or when the pilot pressure of the same pressure is input to both pilot ports 12a and 12b, the left control valve 12
It is located at the neutral position N where no pressure oil is supplied to the left hydraulic motor 7, and the left hydraulic motor 7 is stopped. On the other hand, when the pilot pressure is input only to the forward pilot port 12a, or when the pilot pressure input to the forward pilot port 12a is higher than the pilot pressure input to the reverse pilot port 12b, the left side is set. The control valve 12 is connected to the left hydraulic motor 7
Is switched to the forward position X where the hydraulic oil from the main pump 9 is supplied to the forward port 7a of the vehicle, whereby the left hydraulic motor 7 is driven to move the left traveling unit 5 forward. In this case, as the pilot pressure input to the forward pilot port 12a becomes higher, or as the differential pressure between the pilot pressure input to the forward pilot port 12a and the pilot pressure input to the reverse pilot port 12b becomes larger, Left control valve 1
2, the moving stroke of the left hydraulic motor 7
Drive speed increases. When the pilot pressure is input only to the reverse pilot port 12b, or when the pilot pressure input to the reverse pilot port 12b is higher than the pilot pressure input to the forward pilot port 12a, The left control valve 12 switches to a reverse position Y for supplying the hydraulic oil from the main pump 9 to the reverse port 7 b of the left hydraulic motor 7, whereby the left hydraulic motor 7 moves to the side that moves the left traveling unit 5 backward. It is designed to be driven. In this case, as the pilot pressure input to the reverse pilot port 12b becomes higher,
As the differential pressure between the pilot pressure input to b and the pilot pressure input to the forward pilot port 12a increases, the moving stroke of the left control valve 12 increases, and the driving speed of the left hydraulic motor 7 increases.

On the other hand, reference numeral 14 denotes a pilot valve unit in which four pilot valves 15, 16, 17, 18 of front, rear, left and right are incorporated.
6, 17, and 18 are constituted by variable pressure reducing valves,
These pilot valves 15, 16, 17, 18 output pilot pressure based on the operation of one traveling operation lever 19. Then, the pilot pressure output from the front pilot valve 15 is input to the first shuttle valve 20 and the second shuttle valve 21. The pilot pressure output from the rear pilot valve 16 is input to the third shuttle valve 22 and the fourth shuttle valve 23. The pilot pressure output from the left pilot valve 17 is input to the second shuttle valve 21 and the third shuttle valve 22. The pilot pressure output from the right pilot valve 18 is input to the first shuttle valve 20 and the fourth shuttle valve 23.

Further, the first shuttle valve 20 is provided with a pilot pressure input from the front pilot valve 15,
The high pressure side is selected from the pilot pressure input from the right pilot valve 18 and the left control valve 1 is selected.
2 to the forward pilot port 12a. The second shuttle valve 21 selects the high pressure side from the pilot pressure input from the front pilot valve 15 and the pilot pressure input from the left pilot valve 17 and selects the forward pilot port 13 of the right control valve 13.
output to a. The third shuttle valve 22 includes a pilot pressure input from the rear pilot valve 16 and a pilot pressure input from the left pilot valve 17.
The high pressure side is selected and output to the reverse pilot port 12b of the left control valve 12. Fourth shuttle valve 2
3 selects the high pressure side from the pilot pressure input from the rear pilot valve 16 and the pilot pressure input from the right pilot valve 18 and outputs the selected high pressure side to the reverse pilot port 13b of the right control valve 13.

The traveling operation lever 19 is a joystick-type operation lever which can be tilted in a two-dimensional direction (360 degrees) in front, rear, left and right around a neutral position O which is neutral in front, rear, left and right. The pilot pressure is output from the pilot valves 15, 16, 17, 18 in accordance with the operation of the operating lever 19. This traveling operation lever 1
9 and the pilot pressure output from the pilot valves 15, 16, 17, and 18 are shown in FIGS.
When the traveling operation lever 19 is located at the neutral position O in the front, rear, left and right directions, no pilot pressure is output from all the pilot valves 15, 16, 17, and 18. When the traveling operation lever 19 is operated forward (direction A in FIG. 3) or rearward (direction B in FIG. 3) along the front-rear axis direction from the neutral position O, or leftward along the left-right axis direction. (C direction in FIG. 3), right (FIG.
(D direction), pilot pressures corresponding to the lever operation amounts are output from the pilot valves 15, 16, 17, 18 on the operated side, respectively. further,
When the traveling operation lever 19 is operated to the front left, the front pilot valve 15 and the left pilot valve 1
7 outputs a pilot pressure. Then, in this case, a direction (E in FIG.
Direction), both pilot valves 15,
17 outputs the same pilot pressure. Also, when the operation is performed closer to the front-rear axis than the left-right axis (the AE region in FIG. 3), the output pressure of the front pilot valve 15 becomes higher than the output pressure of the left pilot valve 17, and furthermore, the left-right axis becomes higher than the left-right axis. When the operation is performed closer (the CE region in FIG. 3), the output pressure of the left pilot valve 17 becomes higher than the output pressure of the front pilot valve 15. Similarly, when the traveling operation lever 19 is operated to the rear left, from the rear pilot valve 16 and the left pilot valve 17, and when operated to the front right, from the front pilot valve 15 and the right pilot valve 18. When operated to the rear right, pilot pressure oil is output from the rear pilot valve 16 and the right pilot valve 18, respectively. In this case, when operated in directions (F direction, G direction, H direction in FIG. 3) which are at equal angles to the front-rear axis and the left-right axis, both pilot valves 16 and 1
7, 15 and 18, 16 and 18 output the same pilot pressure, and are closer to the front and rear axes than to the left and right axes (BF,
(AG, BH range), the output pressure of the front or rear pilot valve 15 or 16 becomes higher than the output pressure of the left or right pilot valve 17 or 18, and is closer to the left and right axes than the front and rear axes ( CF in FIG. 3,
(DG, DH range), the output pressure of the left or right pilot valve 17 or 18 becomes higher than the output pressure of the front or rear pilot valve 15 or 16.

In this embodiment, the traveling operation lever 19
Is not operated, that is, in a state in which it is located in the neutral position O, as described above, all the pilot valves 1
No pilot pressure is output from 5, 16, 17, 18
The left and right control valves 12, 13 are located at the neutral position N. Thus, the hydraulic shovel 1 is not running because the hydraulic oil is not supplied to the left and right hydraulic motors 7 and 8.

On the other hand, when the traveling operation lever 19 is operated forward (along arrow A in FIGS. 3 and 4) along the longitudinal axis, the pilot pressure is output from the front pilot valve 15, but the pilot pressure is First and second shuttle valves 20, 21
Are input to the forward pilot ports 12a, 13a of the left and right control valves 12, 13 to switch the control valves 12, 13 to the forward position X.
In this case, since the pilot pressures input to the control valves 12 and 13 are the same, the left and right hydraulic motors 7 and 8 are driven forward at the same speed, and the hydraulic excavator 1 moves straight forward. I do.

When the traveling operation lever 19 is operated rearward (along arrow B in FIGS. 3 and 4) along the longitudinal axis,
The same pilot pressure is input to the reverse pilot ports 12b and 13b of the left and right control valves 12 and 13 as in the case where the front operation is performed in the forward direction. 7 and 8 are driven backward at the same speed, and the excavator 1 goes straight backward.

Further, when the traveling operation lever 19 is operated to the left (in the direction C in FIGS. 3 and 4) along the left-right axis, a pilot pressure is output from the left pilot valve 17, but the pilot pressure is Is input to the forward pilot port 13a of the right control valve 13 via the second shuttle valve 21 and switches the right control valve 13 to the forward position X, while the left control valve is switched via the third shuttle valve 22. The control valve 12 is input to the reverse pilot port 12b and switches the left control valve 12 to the reverse position Y. In this case, since the pilot pressures input to the control valves 12 and 13 are the same, the forward drive of the right hydraulic motor 8 and the
Reverse drive is performed at the same speed.
Spins counterclockwise in place.

Further, when the traveling operation lever 19 is operated rightward (direction D in FIGS. 3 and 4) along the left-right axis, the left-right operation is reversed with respect to the above-described leftward operation. In this state, the same pilot pressure is input to the forward pilot port 12a of the left control valve 12 and the backward pilot port 13b of the right control valve 13, so that the forward drive of the left hydraulic motor 7 and the right hydraulic motor 8 is performed at the same speed, and the excavator 1 spins rightward in that position.

On the other hand, when the traveling operation lever 19 is operated to the front left, the front and left pilot valves 1
The pilot pressure is output from 5 and 17 and the pilot pressure is the first, second and third shuttle valves 20, 2
1 and 22 via the left and right control valves 12 and 1
3 forward pilot ports 12a and 13a and the left pilot valve 1
2b. In this case, when operated in the front left direction (direction E in FIGS. 3 and 4) at equal angles with respect to the front-rear axis and the left-right axis, the front and left pilot valves 15,
The pilot pressure of the same pressure is output from 17, whereby the left control valve 12 is maintained at the neutral position N by inputting the same pilot pressure to the forward and reverse pilot ports 12 a and 12 b, The right control valve 13 is switched to the forward position X. Thus, while the left hydraulic motor 7 is stopped, the right hydraulic motor 8 is driven forward, and the excavator 1 makes a forward pivot turn in the counterclockwise direction. In addition, when operated to the front left (AE region in FIG. 3) near the front-rear axis, the output pressure from the front pilot valve 15 becomes higher than the output pressure from the left pilot valve 17, whereby the left control valve 12 When the input pressure to the forward pilot port 12a is
The pressure becomes higher than the input pressure to the pilot port 2b, and is switched to the forward position X by a stroke corresponding to the pressure difference between the pilot pressures input to the pilot ports 12a and 12b. The output pressure from the high-pressure-side front pilot valve 15 is input to the forward-side pilot port 13a, and the right-side control valve 13 is switched to the forward-side position X. Thus, the left and right hydraulic motors 7 and 8 are both driven forward. In this case, the driving speed of the left hydraulic motor 7 is slower than that of the right hydraulic motor 8, and the excavator 1 turns counterclockwise while moving forward. . Further, when the valve is operated to the front left (the CE area in FIG. 3) near the left and right axes, the output pressure from the left pilot valve 17 becomes higher than the output pressure from the front pilot valve 15, so that the left control valve 12 The input pressure to the reverse pilot port 12b is higher than the input pressure to the forward pilot port 12a, and the reverse pressure is equal to the differential pressure between the pilot pressures input to the pilot ports 12a and 12b. Switch to position Y. The output pressure from the high-pressure left pilot valve 17 is input to the forward pilot port 13a, and the right control valve 13 is switched to the forward position X. Thus, the left hydraulic motor 7 is driven backward and the right hydraulic motor 8 is driven forward. In this case, the driving speed of the left hydraulic motor 7 is lower than that of the right hydraulic motor 8. The excavator 1 spins in a counterclockwise direction at a gentler angle than when operated leftward along.

Further, when the traveling operation lever 19 is operated to the rear left, the pilot pressure is output from the rear and left pilot valves 16 and 17, but in this case, the pilot pressure is output to the front left. Since the operation is in a state of being reversed in the front-rear direction, a brief description will be given.
, The left control valve 12 is switched to the reverse position Y, and the right control valve 13 is held at the neutral position N. Thus, while the left hydraulic motor 7 is driven backward, the right hydraulic motor 8 is stopped, and the hydraulic excavator 1 makes a backward pivot turn in the counterclockwise direction. On the other hand, when the left and right hydraulic motors 7 and 8 are driven rearward when operated to the rear left (BF area in FIG. 3) near the front-rear axis, in this case, the driving speed of the right hydraulic motor 8 is reduced to the left hydraulic motor 7 Later, the excavator 1 turns counterclockwise while moving backward. Further, when operated to the rear left (CF area in FIG. 3) near the left-right axis,
The left hydraulic motor 7 is driven backward and the right hydraulic motor 8 is driven forward. In this case, the driving speed of the right hydraulic motor 8 is lower than that of the left hydraulic motor 7, and the left hydraulic motor 8 is operated leftward along the left and right axes described above. At a gentler angle than in the case, the excavator 1 spins counterclockwise.

When the traveling operation lever 19 is operated to the front right, the front and right pilot valves 15
In this case, the pilot pressure is output from the left and right sides, and in this case, the left and right sides are reversed with respect to the case where the front left operation is performed, and the front right and left axes are equal to the front-rear axis and the left-right axis. When operated in the direction (G direction in FIGS. 3 and 4), the left control valve 12 is switched to the forward position X, and the right control valve 13 is held at the neutral position N.
Thus, the left hydraulic motor 7 is driven forward while the right hydraulic motor 8 is stopped, and the excavator 1 makes a forward pivot turn in the clockwise direction. On the other hand, when the right and left hydraulic motors 7, 8 are driven forward when operated to the front right (in the AG area in FIG. 3) near the front-rear axis, in this case, the driving speed of the right hydraulic motor 8 is reduced to the left hydraulic motor 7. Later, the excavator 1 turns clockwise while moving forward. Further, the front right side near the left / right axis (DG in FIG. 3)
Region), the left hydraulic motor 7 is driven forward and the right hydraulic motor 8 is driven backward. In this case,
The drive speed of the right hydraulic motor 8 is lower than that of the left hydraulic motor 7, and the excavator 1 spins clockwise at a gentler angle than when the right hydraulic motor 8 is operated rightward along the left and right axes described above.

Further, when the traveling operation lever 19 is operated to the rear right, the pilot pressure is output from the rear and right pilot valves 16 and 18, but in this case, the pilot pressure is output to the aforementioned front right. The left control valve 12 is in a neutral state when it is operated in a rear-right direction (H direction in FIGS. 3 and 4) which is at an equal angle with respect to the front-rear axis and the left-right axis. The right control valve 13 is maintained at the position N, and is switched to the reverse position Y. Thus, while the left hydraulic motor 7 is stopped, the right hydraulic motor 8 is driven backward, and the hydraulic excavator 1 makes a backward pivot turn in the clockwise direction. On the other hand, when the right and left hydraulic motors 7 and 8 are driven rearward when operated to the rear right (the BH region in FIG. 3) near the front-rear axis, in this case, the driving speed of the left hydraulic motor 7 is reduced to the right hydraulic motor 8. Later, the excavator 1 turns clockwise while moving backward. Further, when operated in the rear right direction (DH region in FIG. 3) near the left and right axes, the left hydraulic motor 7 is driven forward and the right hydraulic motor 8 is driven backward. In this case, the driving speed of the left hydraulic motor 7 is increased. The hydraulic excavator 1 spins clockwise at a slower angle than the right hydraulic motor 8 and at a gentler angle than when operated rightward along the left and right axes described above.

In the apparatus constructed as described above, the hydraulic excavator 1 moves forward straight, backward straight, counterclockwise spin turn, clockwise spin turn, counterclockwise forward turn, counterclockwise reverse turn, clockwise forward turn, clockwise reverse. Each traveling operation of the turn can be performed by swinging one traveling operation lever 19 of the joystick type in the front, rear, left and right directions. As a result, when it is desired to operate the working device 4 during traveling, the operating lever 19 for the working device 4 can be operated with the other hand or foot while operating the operating lever 19 with one hand. That is, both hands and feet are not blocked as in a conventional traveling operation tool using a pair of left and right traveling operation tools, and workability is improved.

Further, since only one traveling operation lever 19 is required as the traveling operation tool, the number of parts can be reduced, which can contribute to cost reduction.

In addition, the traveling operation lever 19 is centered on a neutral position O, which is neutral in the front, rear, left and right directions, when it is operated forward, it goes straight forward, when it is operated backward, it goes straight back, and in the left direction. When operated, counterclockwise spin turn,
A right-handed spin turn when operated rightward, a forward-turned turn leftward when operated forward-left, a reverse-turned left-handed direction when operated backward-left, and forward-rightward In this case, the operation direction of the travel operation lever 19 and the operation direction of the left and right traveling units 5 and 6 are determined such that the forward turn is made in the clockwise direction when the vehicle is turned, and the backward turn is made in the clockwise direction when the vehicle is operated to the rear right. Therefore, the operator can perform the running operation with a natural feeling without any discomfort.

[Brief description of the drawings]

FIG. 1 is a perspective view of a hydraulic shovel.

FIG. 2 is a hydraulic circuit diagram of a hydraulic motor.

FIG. 3 is a view showing an operation direction of a traveling operation lever.

FIG. 4 is a diagram showing a relationship between operation of an operation lever and driving of a hydraulic motor.

[Explanation of symbols]

 5 Left traveling unit 6 Right traveling unit 7 Left hydraulic motor 8 Right hydraulic motor 12 Left control valve 13 Right control valve 15 Front pilot valve 16 Rear pilot valve 17 Left pilot valve 18 Right pilot valve 19 Traveling operation lever 20 First shuttle Valve 21 Second shuttle valve 22 Third shuttle valve 23 Fourth shuttle valve

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2D003 AB01 BA01 BA02 CA02 DA03 EA01 3D052 AA05 BB08 BB11 DD01 EE01 FF02 GG04 HH01 HH02 JJ00 JJ21 JJ22 JJ24 JJ25 3H089 AA60 BB15 CC08 CC12 DA02 DB47 DB18 EE14 JJ23 AE14 AB11 AB21 AB32 BA04 DA22 EA08 EA20 FB01

Claims (3)

[Claims] 1. A crawler-type traveling body configured to move left and right crawler-type traveling units forward and backward based on driving of corresponding left and right hydraulic motors, respectively. When the left and right control valves are switched to the forward side for supplying hydraulic oil to drive the hydraulic motor forward and the reverse side for supplying hydraulic oil to drive backward, respectively, the switching operation of the control valves is performed from the neutral position back and forth. A traveling operation device for a crawler traveling vehicle that is configured to operate with pilot pressures output from four front, rear, left and right pilot valves in response to operation of a single joystick-type operation lever that can be operated in any of the left and right directions. . 2. The pilot valve according to claim 1, wherein the front pilot valve outputs pilot pressure for switching both left and right control valves to the forward side, and the rear pilot valve outputs pilot pressure for switching both left and right control valves to the reverse side. The left pilot valve outputs pilot pressure to switch the right control valve to the forward side and the left control valve to the reverse side.The right pilot valve outputs the left control valve to the forward side and the right control valve to the reverse side. A traveling operation device for a crawler traveling vehicle, which outputs a pilot pressure to be switched to each other. 3. The pilot oil passage from front, rear, left and right pilot valves to left and right control valves according to claim 2, wherein the high pressure side of the pilot pressure output from each pilot valve is selected and output to the control valve. A traveling operation device for a crawler traveling vehicle in which a shuttle valve is provided.