JPH0497027A - Traveling controller of constructional machinery - Google Patents

Abstract

PURPOSE:To promote controllability by providing an exclusive straight advance ment pedal device around a pair of right and left pedal devices. CONSTITUTION:An exclusice straight advancement pedal device 33 is provided around a pair of pedal devices 7L, 7R. When it is advanced, a tread member 34 of the pedal device 33 is pushed forward to operate. After that, an advancing pilot valve 35 is switched over, pilot pressure from an oil pressure source 37 of the pilot pressure is acted on a pilot pressure receiving section of a pilot selector valve 16L through a shuttle valve 38 and, at the same time, the pilot pressure is acted on a pressure receiving section 2 of a selector valve 16R through a shuttle valve 40, and the selector valves 16L and 16R are simultaneous ly switched to advancing positions a) and c) respectively. While, in the case of a backward movement, the tread member 34 is pushed backward to operate. Then, a pilot valve 36 is switched over, and the selector valves 16L and 16R are simultaneously switched to positions b) and d) for backward movement.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates primarily to a travel control device for construction machinery such as hydraulic excavators.

BACKGROUND OF THE INVENTION FIG. 5 is a perspective view showing the vicinity of a driver's seat 1 of a hydraulic excavator equipped with a conventional travel control device.

In the figure, 2 is the floorboard, 3L + 3R are the left and right road surface members,
4L14R are left and right road surface members 3L, respectively.

Traveling levers 5L and 5R fixed to 3R are operating levers for work. FIG. 6 is a circuit diagram of a main part of a hydraulic excavator equipped with a conventional travel control device.

In the figure, 7L+7R is a pair of left and right pedal devices, 8,
9 is a forward and reverse pilot valve for the pedal device 7L, 1
0. ll is the forward and reverse pilot valve of the pedal device 7R, 12+-, 12I? are left and right travel motors, 13L
, 13R are cylinders for adjusting the tilting angles of the travel motors 12L, 12R, 14L, 14. ? are respectively speed switching valves, 15
16□7 and 16R are pilot switching valves for controlling the travel motors 12L and 12R; 17. is a solenoid valve for switching between 1st and 2nd speeds;
18 is the main pump, 19 is the pilot pump, 20 is the oil tank, 21 is the engine, and 22 is the engine 2.
1 is a governor, 23 is a stamping motor which is an actuator for the governor 22, 24 is an engine rotation sensor, 25
is a controller, and 26 is a 7-inch engine rotation mode switch. Note that when changing the engine rotation mode, the mode changeover switch 26 is switched to one of the H position (high speed rotation position), S position (medium speed rotation position), and FC position (low speed rotation position) as required. Also, the symbols Eii, Roguchi, Harbor, and 212 indicate the connections of the pilot pipes.

Next, the conventional travel control device shown in FIGS. 5 and 6 will be described. By operating the pair of pedal devices 7L and 7R, the pyro 1. Pilot pressure is derived from a pilot valve (any one of pilot valves 8, -, 11), and the pilot pressure is transferred to a pair of pilot switching valves 16L.
, 16R, each pilot pressure received pressure 1 (27, ~, 3
0 (one of the pilot pressure receiving parts) to switch control the pilot switching valves 16L and lez+, and operate the left and right travel motors 12L and 12R. Note that by operating the switch 31 that passes through the first speed/second speed switching solenoid valve 15 and the mode changeover switch 26, the traveling motor 12. ．． The rotational speed of 122 can be set to a desired running speed.

Problems to be Solved by the Invention In conventional tracked vehicles, when traveling straight ahead, the driver performs left and right operations with his left and right feet, respectively. In this case, the timings of simultaneous left and right operations with both feet do not match perfectly, and both feet do not move in the same way at the same time, so the amount of pedal operation of the road surface member is not equal on the left and right sides. In particular, when the driver manually operates the work operating lever while driving straight, he/she neglects to pay attention to both legs, which is extremely dangerous as the tracked vehicle may meander.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and provide a travel control device that can be operated by a driver with one foot when a crawler vehicle travels straight ahead.

Means for Solving the Problems The means of the present invention taken to solve the above problems are as follows: (1) A. Providing one pedal device exclusively for straight-line travel near the pair of pedal devices; B. The pair of pedals described above. The pilot pressure derived from each of the forward pilot valves of the device and the pilot pressure derived from the forward pilot valve of the straight-travel dedicated pedal device are selectively used to advance the pair of pilot switching valves. The pilot pressure is applied to the pilot pressure receiving section for driving, and either the pilot pressure derived from the reverse pilot valve of the pair of pedal devices, or the pilot pressure derived from the reverse pilot valve of the straight-ahead pedal device. One of the pilot pressures is configured to selectively act on the reverse pilot pressure receiving portion of the pair of pilot switching valves.

(a) For one pedal device exclusively for straight-ahead travel installed near the pair of pedal devices, a detection means for detecting that the pedal device exclusively for straight-ahead travel is in an operating state is provided, and a detection signal from the above-mentioned detection means is provided. is input to the controller, and based on the detection signal, the controller outputs an engine rotation speed command signal to the engine governor. It was configured to adjust the rotational speed to a preset traveling speed.

(3) A. A one-way operation pedal device is provided near the pair of pedal devices, and B. A pipe line passing from the pilot valve of the one-way operation pedal device to the pilot pressure receiving part of the pilot switching valve. A front and rear selection valve is interposed in the front and rear selection valves, and a changeover switch is provided to control the front and rear selection valves;
- Selectively cause one of the viroft pressures derived from the pilot valve of the directional operation pedal device to act on the pilot pressure receiving portion of the pair of pilot switching valves; 2. Operate the changeover switch; When the one-way operation pedal device is operated, the pair of pilot switching valves are simultaneously switched to a forward position or a reverse position.

(2) A. A straight-ahead driving operation section is formed so that the driver can simultaneously operate a pair of left and right road surface members that the driver's feet touch in the same direction with one foot, and the vehicle travels straight. At times, the driver performs a depressing operation on the operation part for straight traveling with one foot, and when the vehicle changes the traveling direction, the driver performs a depressing operation on a required road surface member from a pair of left and right road surface members.

Effect (1) A. When operating a pair of left and right pedal devices,
A pair of pilot switching valves perform switching operations similar to those of the prior art.

(b) When the straight-travel-only pedal device is operated for forward movement, the pair of pilot switching valves can be simultaneously switched to the forward position, and when the straight-line-only pedal device is operated for reverse movement, the pair of pilot switching valves can be simultaneously switched to the reverse position.

(b) Since the pedal device exclusively for straight-line driving is provided with a button yometer, when the pedal device exclusively for straight-line driving is operated, its detection signal is input to the controller.

Based on the detection signal, the controller outputs an engine rotation speed command signal to the engine governor via the stamping motor.

At the same time, an ON/OFF switching operation command signal is output to the 1st/2nd speed switching switch.

C. According to the above item B, the rotational speed of the travel motor can be automatically adjusted to the travel speed set in advance on the travel speed selection switch.

(3) A. When operating a pair of left and right pedal devices,
A pair of pilot switching valves performs the same switching operation as in the prior art.

When the one-way operating pedal device is operated by operating the selector switch, the pair of pilot selector valves can be simultaneously switched to the forward position or the reverse position.

(4-b. When performing a depression operation on a required road surface member among the pair of left and right road surface members, the same operation as in the prior art can be performed.

In other words, the driver can run the vehicle in a straight line by depressing the straight-line driving operation section with one foot.

Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

(1) FIG. 1 is a main circuit diagram showing a traveling control device 32 according to claim 1 of the present invention. In the figure, the same reference numerals are given to the same components as in the prior art. Reference numeral 33 denotes a pedal device exclusively for straight-line travel, 34 denotes a road surface member 35 and 36 of the pedal device 33 exclusively used for straight-line travel, pilot valves, 37 a pilot pressure oil pressure source, 38, 39, 40.
41 are pilot pressure selection shuttle valves.

Next, the configuration of the travel control device 32 according to the present invention will be explained in the first section.
Let's talk about the diagram. One pedal device 33 dedicated to straight travel is provided near the pair of pedal devices 70, 7R, and the pair of pedal devices 7L, 71? Each forward pilot valve 8
, 10 and the pilot pressure derived from the forward pilot valve 35 of the straight-ahead pedal device 33, the pair of pilot switching valves 18L, 1eF? The forward pilot pressure receiving portions 27 and 29 of the pair of pedal devices 7L and 7R are applied to the forward pilot pressure receiving portions 27 and 29, and the pilot pressure derived from the reverse pilot valves 9 and 11 of the pair of pedal devices 7L and 7R, respectively, and the backward movement of the straight-ahead pedal device 33 are One of the pilot pressures derived from the pilot valve 36 is selectively switched to the pair of pilot switching valves 18.
It is made to act on the reverse pilot pressure pressure receiving part 28.30 of L and 16R. And a pedal device 33 exclusively for straight traveling
During the forward operation, the pair of pilot switching valves 16L,
16. are simultaneously switched to the E position and the G position, respectively, and when the straight-ahead pedal device 33 is operated in reverse, the pair of pilot switching valves 16t, , ISR are simultaneously switched to the E position and the H position, respectively.

Next, the functions of the travel control device 32 will be described. First, when operating the pair of left and right pedal devices 7L and 7R, a pair of pilot switching valves 16L is used.

16□ performs the same switching operation as in the prior art. However, when attempting to move the hydraulic excavator (not shown, but a crawler vehicle equipped with this travel control device 32) forward, the road surface member 34 of the straight-travel pedal device 33 is depressed forward. Since the forward pilot valve 35 is switched, the pilot pressure from the pilot pressure oil pressure source 37 passes through the pilot valve 35 and the pipe line 42, and one passes through the pipe line 43, the nyatle valve 38, and the pipe line 44, and then passes through the pilot switching valve. It acts on the pilot pressure receiving section 27 of 16L. At the same time, the pilot pressure branches off at the pipe 42, passes through the pipe 45, the shuttle valve 40, and the pipe 46, and acts on the pilot pressure receiving portion 29 of the pilot switching valve 16R. Pilot switching valve 18L, 16
At the same time, R is switched to the E position and the G position for forward movement, respectively. Further, when the vehicle is to move backward, the road surface member 34 of the pedal device 33 exclusively for straight-ahead movement is depressed backward. Since the reverse pilot valve 36 is switched, the pilot switching valve 1
6L and 16R are simultaneously switched to the reverse position and the H position, respectively.

Therefore, by depressing one pedal device 33 exclusively for straight travel, the hydraulic excavator can be caused to travel straight forward or backward.

(2) FIG. 2 is a main part circuit diagram showing a traveling control device 47 according to claim 2 of the present invention. In the figure, the same reference numerals are given to the same components as in the prior art. Reference numeral 33 denotes a pedal device exclusively for straight-line travel, 34 denotes a road surface member 35, 36 of the pedal device 33 exclusively for straight-travel, pilot valves, 38.3940.41 each pilot pressure selection shuttle valve, 48 a potentiometer provided in the pedal device 33, 25 ' is a controller, 49 is a running speed selection switch, 50 is a switch for changing between 1st and 2nd speeds, and the symbols ``Lilli'', ``Nunnu'', ``Rule'', and ``O'' indicate the connections of the conduits, respectively.

Next, the configuration of the travel control device 47 according to the present invention will be explained in a second manner.
Let's talk about the diagram. A potentiometer 48 is provided for one straight line pedal unit 33 provided near the pair of pedal units 71.7R to detect whether the straight line pedal unit 33 is in an operating state, and the potentiometer 48 sends a run detection signal. is input to the controller 25', and based on the detection signal, the controller 25'
The engine speed command signal is outputted to the governor 22 of the engine 21, and when the straight-ahead pedal device 33 is operated, the rotational speed of the travel motors 12t and 12p is set to the speed set in advance in the travel speed selection switch 49. Configured to adjust.

Next, the functions of the travel control device 47 will be described. When the straight-travel exclusive pedal device 33 is operated, a detection signal thereof is inputted from the potentiometer 48 to the controller 25'. Based on the detection signal, the controller 25' outputs an engine rotation speed command signal to the governor 22 of the engine 21 via the stepping motor 23. At the same time, an on/off switching operation command signal is output to the first/second speed switching switch 50. Thereby, the rotational speed of the travel motors 12L, 12R is set to the travel speed (a + ~, f
(either speed) can be adjusted automatically.

(3) FIG. 3 is a main part circuit diagram showing a traveling control device 51 according to claim 3 of the present invention. In the figure, the same reference numerals are given to the same components as in the prior art. 38, 39, 40. 41 are pilot pressure selection shuttle valves, 37 is a pilot pressure oil pressure source, 52
53 is a road surface member of the unidirectional operation pedal device 52, 54 is a pilot valve, 55 is a forward/reverse selection valve, 56.57 is a left and right solenoid of the forward/reverse selection valve 55, and 58 is a road member for the one-way operation pedal device 52. Changeover switch, 59 is power supply, F
, R are each in front of the changeover switch 58.

This is the reverse switching operation position.

Next, the configuration of the travel control device S1 according to the present invention will be explained in a third example.
Let's talk about the diagram. One one-way operation pedal device 52 is provided near the pair of pedal devices 71, 7R, and the one-way operation pedal device 52 has a pilot valve 54 to a pilot switching valve 16L.

168 pilot pressure receiving portions 27. A forward/reverse selection valve 55 is interposed in the conduit leading to . . . . . . . 30 and the pilot pressure derived from the pilot valve 54 of the one-way operation pedal device 52. Pilot pressure receiving section 27. 〜,30. When the changeover switch 58 is operated to operate the one-way operation pedal device 52, the pair of pilot changeover valves 16t, 16R are simultaneously switched to the forward position H, H, or the reverse position, respectively. Configured.

Next, the functions of the travel control device 51 will be described. First, when operating the pair of left and right pedal devices 7L and 7R, the pair of pilot switching valves 16L16R performs the same switching operation as in the prior art. However, when attempting to move the hydraulic excavator (not shown, but a crawler vehicle equipped with this travel control device 51) forward, the changeover switch 58 is operated to the 2 position and the one-way operation pedal device 52 is operated. Since the forward/reverse selection valve 55 has been switched to the forward position 7, the pilot pressure from the pilot pressure oil pressure source 37 passes through the pilot valve 54, the 7 position of the forward/reverse selection valve 55, and the pipe 60.
One side acts on the pilot pressure receiving portion 27 of the pilot switching valve 16L via the pipe line 43, the shuttle valve 38, and the pipe line 44. At the same time, the pilot pressure branches off at the pipe 60, passes through the pipe 45, the shuttle valve 401, and the pipe 46, and acts on the pilot pressure receiving portion 29 of the pilot switching valve 16R. Pilot switching valve 16L, 16F? At the same time, they are switched to the E position and G position for forward movement, respectively.

Further, when the vehicle is to be moved backward, the changeover switch 58 is operated to the R position and the one-way operation pedal device 52 is operated. Since the forward/reverse selection valve 55 has been switched to the reverse position force, the pilot switching valve 16L is activated in the opposite manner to the forward movement.
, 18R are simultaneously switched to the reverse position and the H position, respectively.

Therefore, by operating the changeover switch 58 and the one-way operation pedal device 52, the hydraulic excavator can be caused to travel straight forward or backward.

(4) FIG. 4 is a perspective view showing a travel control device 61 according to claim 4 of the present invention. In the figure, 62L
, 62R are road surface members on the left and right sides of the travel control device 61, and 63 is a straight driving operation section (fourth wheel) formed so that the driver can simultaneously press and operate the road surface members 62L and 62R in the same direction with one foot.
64L and 64R are travel levers fixed to the road surface members 62L and 62R, respectively, and 65 is a bracket that rotatably supports the road surface members 62L and 62R, respectively. Next, the configuration of the travel control device 61 according to the present invention will be described with reference to FIG.

A straight-ahead driving operating section 63 is formed so that the driver can operate the pair of left and right road surface members 62L, 628 in the same direction at the same time with one foot, and when the vehicle is traveling straight, the driver can operate the straight-ahead driving with one foot. The operating unit 63 is configured to be depressed, and when the vehicle changes the running direction, the desired road surface member of the pair of left and right road members 62L and 62R is depressed.

Next, the functions of the travel control device 61 will be described. When performing a depression operation on a required road surface member among the pair of left and right road surface members 62L and 62R, the same operation as in the prior art can be performed. When the driver depresses the straight-ahead driving operation section 63 with one foot, the vehicle can travel straight ahead.

Effects of the Invention When the conventional crawler vehicle travels straight ahead, the driver performs left and right operations with his left and right feet, respectively. In this case, the timing of performing the right and left operations with both feet at the same time did not completely match, or the two feet did not move in the same way at the same time, so the amount of pedal operation of the road surface member was not equal on the left and right sides. In particular, when the driver manually operates the work operating lever while traveling straight, the tracked vehicle may meander, which is extremely dangerous, as the driver is not paying attention to both feet.

However, in the travel control device according to the present invention, one pedal device dedicated to straight travel is provided near the pair of left and right pedal devices. As a result, when a tracked vehicle such as a hydraulic excavator is caused to travel straight, the driver can operate the pedal devices exclusively for straight travel with one foot. The pair of pilot switching valves that control the left and right travel motors perform the same operation at exactly the same timing, allowing accurate straight-line travel. To improve the workability and driving operability of a hydraulic excavator, since even when the driver manually operates a work operating lever when traveling straight, there is no need for the driver to concentrate on both legs as in the conventional technology. I can do it. Moreover, when changing driving direction, etc.
Although it does not use a pedal device exclusively for straight-ahead driving, it is safe because it can be operated in the same way as the conventional technology.

Furthermore, in a travel control device that is equipped with an operating section for straight-ahead travel so that the driver can simultaneously operate a pair of road surface members in the same direction with one foot, the same effect as described above can be achieved without providing a pedal device exclusively for straight-ahead travel as described above. can be emitted.

In addition, in a travel control device in which a pedal device exclusively for straight-line travel is equipped with a detection means for detecting whether the pedal device is in an operating state, it is possible to use a pedal device for straight-ahead travel for a short distance in the longitudinal direction while performing extraction/towering or excavation work. Since the travel speed is automatically adjusted to a preset value, it is convenient and safe for trench excavation work, deep hole excavation work, etc.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a main part showing a travel control device according to claim 1 according to the present invention, FIG. 2 is a circuit diagram of a main part showing a travel control device according to claim 2 according to this invention, and FIG. FIG. 4 is a perspective view showing the driving control device according to claim 4 according to the present invention, and FIG. 5 is a conventional technology. A perspective view showing the vicinity of the driver's seat of a hydraulic excavator equipped with a travel control device, No. 6
The figure is a circuit diagram of a main part of a hydraulic excavator equipped with a conventional travel control device. 1------Pedal device 35.36.54-111 Pilot valve 12 R---
------------One travel motor 16 R----
−−−−−−−−−−−−Pilot switching valve 25”−
-------1-------------------Controllers 47, 51, 61--1 Travel control device Straight-line exclusive pedal device 7L, 7. 8~11°12L. 16L. 25゜32゜Fig. 1 37-/@ 37-[Yes] Pilot pressure oil pressure source direction operation pedal device changeover switch Straight travel operation section and above

Claims (4)

[Claims] (1) By operating a pair of pedal devices, pilot pressure is derived from each of the pilot valves, and the pilot pressure is applied to the pilot pressure receiving portion of each of the pair of pilot switching valves to control switching of the pilot switching valve. , in a crawler vehicle configured to operate left and right traveling motors, a single linear pedal device is provided near the pair of pedal devices, and the pilot pressure derived from the forward pilot valve of each of the pair of pedal devices is , one of the pilot pressures derived from the forward pilot valve of the straight-travel dedicated pedal device is selectively applied to the forward pilot pressure receiving portion of the pair of pilot switching valves; The pair of pilot switching valves selectively select one of the pilot pressure derived from the reverse pilot valve of each of the pedal devices and the pilot pressure derived from the reverse pilot valve of the straight-ahead pedal device. A travel control device for construction machinery, characterized in that it is configured to act on a reverse pilot pressure receiving section of a construction machine. (2) A detection means for detecting that the straight-ahead pedal device is in operation is provided for a straight-ahead pedal device installed near a pair of pedal devices, and a detection signal from the detection device is sent to the controller. In addition, based on the detection signal, the controller outputs an engine rotation speed command signal to the engine governor, so that when the straight-ahead pedal device is operated, the rotation speed of the travel motor is set in advance. A travel control device for a construction machine according to claim 1, characterized in that the device is configured to adjust the speed of the construction machine. (3) By operating a pair of pedal devices, pilot pressure is derived from each of the pilot valves, and the pilot pressure is applied to the pilot pressure receiving portion of each of the pair of pilot switching valves to control switching of the pilot switching valve. In a crawler vehicle configured to operate left and right traveling motors, a one-way operation pedal device is provided near the pair of pedal devices, and the pilot valve of the one-way operation pedal device is connected to the pilot switching valve. A forward/reverse selection valve is interposed in the conduit leading to the pilot pressure receiving section, and a changeover switch is provided to control the forward/reverse selection valve, and the pilot pressure derived from the respective pilot valves of the pair of pedal devices; One of the pilot pressures derived from the pilot valve of the one-way operation pedal device is selectively applied to the pilot pressure receiving portion of the pair of pilot switching valves, and the one-way operation is performed by operating the changeover switch. A travel control device for construction machinery, characterized in that the pair of pilot switching valves are simultaneously switched to a forward position or a reverse position when an operating pedal device is operated. (4) In a driving pedal device equipped with a pair of left and right road surface members to which the driver's feet are attached, a straight-line driving operation section is provided so that the driver can simultaneously operate the pair of road surface members in the same direction with one foot. When the vehicle is traveling straight, the driver depresses the operation section for straight traveling with one foot, and when the vehicle is changing the traveling direction, the driver presses the required road surface member from the pair of left and right road surface members. A travel control device for construction machinery, characterized in that the device is configured to perform a stepping operation.