JPH0654024B2 - Travel control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a travel control device for a hydraulically driven construction machine, and more particularly to a travel control device for a construction machine driven by two hydraulic motors. Regarding

[Conventional technology]

Crawler-type hydraulically driven construction machines generally drive the left and right trucks with separate hydraulic motors, and control the discharge flow rate or discharge flow rate and discharge direction of the pressure oil sent to these hydraulic motors. To change the direction of.

FIG. 8 shows a hydraulic circuit according to this conventional travel control device.

In FIG. 8, this hydraulic circuit includes a hydraulic motor 1 for driving a track on one side (left side in the traveling direction), a hydraulic motor 2 for driving a track on the other side (right side in the traveling direction), and a hydraulic motor 1, respectively. Direction switching valves 3 and 4 for controlling the discharge flow rate and the discharging direction of the pressure oil 2, pressure reducing valves 7, 8 and 9, 10 for controlling the pilot pressure of the direction switching valves 3, 4, and pressure reducing valves 7, 8 and Mainly composed of operating levers 5 and 6 for operating 9 and 10, respectively, separate hydraulic pressure sources 11 and 12 are provided for the hydraulic motors 1 and 2, respectively, and pressure reducing valves 7, 8 and 9, 10 A hydraulic pressure source 13 for control was arranged in the. As described above, in the related art, an operation system for driving the left hydraulic motor 1 by the operation lever 5,
The operating system for driving the hydraulic motor 2 on the right side by the operating lever 6 is provided independently of each other.
As shown in the plan view of FIG. 4, the operation levers 5 and 6 were erected upright in front of the driver's seat 14 (upper side in the drawing). Then, the driver operates the operation lever 5 with his left hand,
The operating lever 6 is independently rockable by the right hand in the front and rear directions (directions of arrows F and B in the drawing).

[Problems to be solved by the invention]

However, as described above, with both hands, the operation lever 5,
If 6 is operated, it is difficult to operate other actuators, such as the front of the hydraulic shovel, the blade of the bulldozer, and the like, which may hinder the operation. Further, when moving forward and backward, the operating direction of the operation lever and the traveling direction match, so ergonomics are good, but when changing the traveling direction, one operating lever, for example, the left operating lever 5 is used. In the forward direction (the direction of arrow F), the other operating lever, in this case the right operating lever 6 must be operated less than the neutral position or the operating lever 5. This operation is unnatural in terms of ergonomics because the operation direction and the traveling direction do not match, and improvement has been desired.

The present invention has been made in view of the above-mentioned conventional circumstances, and an object thereof is to provide a traveling control device for a construction machine which is excellent in operability and has no problem in terms of artificial engineering.

[Means for solving problems]

In order to solve the problems of the prior art and achieve the above object, the present invention is directed to two hydraulic motors that respectively drive the left and right traveling devices, and the discharge flow rate of the pressure oil of the hydraulic motors according to the operation of the operating means. And a control means for controlling the discharge direction, the operating means comprises a single operating lever swingable in one direction and rotatable about an axis, and a forward / backward movement. The detection means for detecting the swing direction and swing angle of the operation lever to be converted, the detection means for detecting the rotation direction and rotation angle of the operation lever converted to the turning motion, and the processing of signals from both detection means. The control means is provided with a signal processing means for transmitting a control signal according to the operation of the operation lever.

[Action]

According to the above means, the operation lever is set to be swingable in the front-back direction, for example, and the direction inclined from the neutral position and the discharge direction of the pressure oil of the hydraulic motor and the inclined angle and the pressure oil of the hydraulic motor are set. The respective discharge flow rates are correlated and the hydraulic motors are driven in a state where the discharge directions of the pressure oils of the two hydraulic motors are equal to the discharge flow rates. As a result, the forward and backward movements can be performed through a general operation lever. In addition, the direction and angle of rotation of the operation lever from the neutral position are correlated with the discharge direction and discharge flow rate of the pressure oil of one hydraulic motor, whereby, for example, when the operation lever is rotated clockwise, the traveling device on the left side is rotated. Only the hydraulic motor that drives
You can turn right. Therefore, by performing the front-back operation and rotation operation of the operating lever at the same time, the forward / backward speeds, turning radii, etc. according to the respective operating amounts can be arbitrarily selected, and one operating lever can be used as in the conventional case. Maneuverability can be obtained.

〔Example〕

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

1 to 7 are for explaining a travel control device according to an embodiment of the present invention. FIG. 1 is an explanatory view showing a schematic configuration of the travel control device, and FIG. 2 shows an operation direction. FIG. 3 is a plan view of the driver's seat, FIG. 3 is an explanatory view showing the traveling direction of the construction machine, and FIGS. 4 to 7 are relationships between a voltage value corresponding to the detection angle of the operating lever and a current value corresponding to the voltage value. FIG. In the following, the same reference numerals will be given to the constituent elements if they are the same as or the same as those in the conventional art, and the description of the respective portions overlapping with the conventional example will be appropriately omitted.

First, in FIG. 1, the operation lever 20 is provided with an operation knob 21 at the tip and a disc-shaped rotating portion 22 is formed at the base end side.
It is rotatably supported by. Furthermore, this support member 2
3 is a base 25 standing upright from the floor 24 of the driver's seat 14
It is mounted swingably via a pin 26. As a result, the operation lever 20 is free to rotate with respect to the support member 23, but is integrated with the support member 23 when swinging with respect to the pin 26. Of course, in reality, if these rotational movements and rocking movements are completely free, there is a possibility that the other will move when one is operated, so two springs should be opposed to each other and the spring return should bring the neutral position. It is more convenient to operate it.

Rotating part 22 on the base end side of the operating lever 20 in the support member 23
A displacement meter such as a potentiometer 27 serving as a rotation angle detecting means of the support member 23 is disposed in a portion opposite to the support member 23. The support member 23 and the rotation angle detecting portion of the potentiometer 27 are coaxial with each other via a coupling 28. Linked above. Further, for example, a potentiometer 29 as a swing angle detecting means is also provided on the extension of the rotation axis of the pin 26, and the rotation angle detecting portion thereof has the potentiometer 27.
Are coupled coaxially with each other via a coupling 30.

The detection signals detected by the potentiometers 27 and 28 are sent to a signal processing device 31, which is subjected to predetermined conversion to discharge the pressure oil of the hydraulic motors 1 and 2 shown in FIG. Electromagnetic proportional valves 32, 3 for controlling the pilot pressure of directional control valves 3, 4 for controlling the flow rate and discharge direction
Control signals are sent to 3, 34 and 35. Signal processing device 3
1 can use a microprocessor or can be composed of a simple electric circuit. The operation lever 20, the potentiometers 27 and 29, and the signal processing device 31 constitute an operation means. In addition, the hydraulic motors 1 and 2, the direction switching valves 3 and 4, and the hydraulic power source 11,
The hydraulic circuit including 12 and 13 is the same as the conventional example.

Next, the operation of the travel control device configured as described above will be described.

The solenoid proportional valves 32, 33, 34, 35 generate a pilot pressure proportional to the current value Q passing therethrough and correspond to the pressure reducing valves 7, 8, 9, 10 of FIG. 8, respectively. To do.

Then, as shown in FIG. 3, the traveling patterns of the construction machine are (I) forward (arrow H direction), (II) backward (arrow I direction), (III) right turn forward (arrow J direction), (IV) Right turn backward (arrow K direction) (V) Left turn forward (arrow L direction) (VI)
Turn left backward (direction of arrow M) (VIII) Turn right (direction of arrow N)
(VIII) Left turn (direction of arrow P) is roughly classified into eight types, and the correlation between the operation of the operation lever 20 of the representative example, the signal processing state, and the traveling state will be described. At this time, the potentiometers 27, 28 are set at generated voltages as shown in the relationship between the manipulated variable and the voltage in FIG. 4 (a), for example, where the center of rotation or the center of swinging has an intermediate value.

(I) Forward movement In this case, the operation lever 20 is pushed forward, that is, pushed in the arrow F direction in FIGS. 1 and 2 to move in the same direction. At this time, the voltage V detected by the potentiometer 29 according to the swing angle θ is proportionally output from the intermediate value Vm to the maximum value Vmax as shown in FIG. 4 (a). On the other hand, the signal processor 31 performs signal processing to generate the currents Q ₃₂ and Q ₃₄ shown in FIG. 4 (b), which are proportional to the voltage V as shown in FIG. 4 (a), respectively. , 34 to generate a pilot pressure proportional to this current value.

As a result, the directional control valves 3 and 4 in FIG. 8 are actuated by a predetermined amount, the hydraulic motors 1 and 2 respectively rotate in the forward direction, and the construction machine moves straight in the direction of arrow H in FIG.

(II) Backward In this case, the operating lever 20 is pulled backward, that is, pulled in the direction of arrow B in FIGS. 1 and 2 and moved in the same direction. At this time, the voltage V detected by the potentiometer 29 according to the swing angle θ is proportionally output from the intermediate value Vm to the minimum value V _miu as shown in FIG. 5 (a). On the other hand, the signal processing device 31 performs signal processing to generate the currents Q ₃₃ and Q ₃₅ shown in FIG. 5B, which are proportional to the voltage V as shown in FIG. 5B, respectively. , 35 to generate a pilot pressure proportional to this current value.

As a result, the directional control valves 3 and 4 in FIG. 8 are actuated by a predetermined amount in the direction opposite to the above (I), the hydraulic motors 1 and 2 are respectively rotated in the backward direction, and the construction machine is operated by the arrow in FIG. Go straight in the I direction, that is, backward.

(III) Forward right turn In this case, the operation lever 20 is rotated forward (direction of arrow F) and the operation knob 21 is rotated right (direction of arrow R in FIGS. 1 and 2). Then, when the potentiometers 27, 29 each show a value equal to or greater than the intermediate value Vm, first, for the solenoid proportional valve 32, as shown in (I), the voltage proportional to the voltage value thereof is shown in FIG. 6 (b). A current value Q ₃₂ as shown in (1) is sent to cause the hydraulic motor 1 to perform the same operation as (I). on the other hand,
For the solenoid proportional valve 34, a current value Q corresponding to the detected voltage V ₀ from the potentiometer 29 corresponding to the operation amount (swing angle) θ ₀ of the operation lever 20 in the direction of arrow F at that time.
Within a range not exceeding ₀ , a current value Q ₃₄ as shown in FIG. 6 (c) is sent, and a pilot pressure proportional to this current value Q ₃₄ is generated. As a result, the discharge flow rate of the pressure oil of the hydraulic motor 2 becomes smaller than the discharge flow rate of the hydraulic motor 1, and the difference causes the construction machine to move forward in the arrow J direction while making a right turn.

(IV) Right turn backward In this case, the operation lever 20 is rotated backward (direction of arrow B) and the operation knob 21 is rotated right (direction of arrow R in FIGS. 1 and 2). When the potentiometers 27 and 29 each show a value equal to or less than the intermediate value Vm, the solenoid proportional valve 33 is shown in FIG. 7 (b) proportional to its voltage value as described in (II). A current value Q ₃₃ as shown is sent to cause the hydraulic motor 1 to perform the same operation as the above (II). On the other hand, for the solenoid proportional valve 35, a current value Q ₁ corresponding to the detected voltage V ₁ from the potentiometer 29 corresponding to the operation amount (swing angle) θ ₁ of the operation lever 20 in the direction of the arrow B at that time. The current value Q ₃₅ as shown in FIG.
Is generated and a pilot pressure proportional to this current value Q ₃₅ is generated. As a result, the discharge flow rate of the pressure oil of the hydraulic motor 2 becomes smaller than the discharge flow rate of the hydraulic motor 1, and the difference causes the construction machine to retreat while making a right turn in the direction of arrow K.

In addition, the patterns shown in (V) to (VIII) can be realized by similar signal processing. The following table shows the proportionality of the operation of these running patterns and the operated valves to the conventional example.

As described above, according to the above-described embodiment, the swing angle and the swing direction of the operation lever 20, and the rotation angle and the rotation direction of the operation knob 21 (integrated with the operation lever 20) at the tip of the operation lever 20 are set as follows.
The signal can be converted into the operation of the solenoid proportional valve 34 via the signal processing device 31, and the solenoid proportional valve 32 can control the discharge flow rate and the discharge direction of the pressure oil of the hydraulic motors 1, 2. That is, the traveling control of the construction machine becomes possible only by tilting the operation lever 20 forward and backward with one operation lever 20 and rotating the operation lever 20 in the left and right direction in a bending direction. By combining the swinging operation and the turning operation of the operating lever 20, various traveling is possible.

Although the solenoid proportional valve 32 is used to control the hydraulic motors 1 and 2 in the above-described embodiment, other than that, for example, O
The same operation can be performed by using an N-OFF solenoid valve.
Although the above description has been made with the open circuit as shown in FIG. 8, when the traveling is a closed circuit drive, the directional control valves 3 and 4 in the figure are replaced by the regulator of the closed circuit pump. It can be controlled in the same manner.

〔The invention's effect〕

As is apparent from the above description, the present invention has been made such that the swing angle and the rotation angle are detected and the discharge flow rate and discharge direction of the pressure oil of the two hydraulic motors on the left and right can be controlled by operating one operating lever. According to the above, since the operating direction of the operating lever matches the traveling direction of the construction machine, and the operating amount and the traveling speed are correlated, there is no ergonomic reasonably easy operation with one hand. It is possible to provide a traveling control device.

[Brief description of drawings]

1 to 7 are for explaining an embodiment of the present invention. FIG. 1 is an explanatory view showing a schematic configuration of a travel control device, and FIG. 2 is a plan view of a driver's seat section showing an operation direction. , FIG. 3 is an explanatory view showing the traveling direction of the construction machine, FIG. 4, FIG.
6 and 7 are explanatory views showing the relationship between the voltage value corresponding to the detected angle of the operating lever and the current value corresponding to the voltage value, and FIGS. 8 and 9 are for explaining the conventional example. FIG. 8 is a hydraulic circuit diagram of a conventional travel control device, and FIG. 9 is a plan view of a driver's seat section showing an operation direction. 1, 2 ... Hydraulic motor, 3, 4 ... Directional switching valve, 20 ...
… Operation lever, 21 …… Operation knob, 22 …… Rotating part, 2
3 ... Support member, 25 ... Base, 26 ... Pin, 2
7, 29 ... Potentiometer, 31 ... Signal processing device, 32, 33, 34, 35 ... Electromagnetic proportional valve.

Claims (1)

[Claims] 1. A travel control device comprising two hydraulic motors for respectively driving left and right traveling devices, and a control means for controlling a discharge flow rate and a discharge direction of pressure oil of the hydraulic motor according to an operation of an operating means. , The operating means detects the swinging direction and swinging angle of one operating lever which is swingable in one direction and rotatable about an axis, and the operating lever which is converted into forward and backward movement. The detection means, the detection means for detecting the rotation direction and the rotation angle of the operation lever converted into the turning motion, and the processing of the signals from both detection means perform the control signal corresponding to the operation of the operation lever to the control means. A traveling control device comprising: a signal processing unit for transmitting the signal.