JP2587658Y2 - Travel control device for construction machinery - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling control device for a construction machine.

[0002]

2. Description of the Related Art A traveling control device for a construction machine controls left and right hydraulic motors for driving left and right crawler tracks of the construction machine with left and right traveling control valves, respectively.

Conventionally, as shown in FIG. 2, left and right pedals 5, 6 are provided for left and right pilot valves 3, 4 for controlling left and right traveling control valves 1, 2, respectively. The levers 7, 8 are integrally mounted on the lower surface of the distal end.

[0004] The left and right pilot valves 3 and 4 control the left and right travel control valves 1 and 2 by operating the pedals 5 and 6 or the levers 7 and 8 with the left and right feet or hands of the operator.

[0005]

In the conventional lever / pedal integrated operation unit, when the travel control valves 1 and 2 are operated, the pedals 5 and 6 and the levers 7 and 8 move simultaneously. As shown, the lever 7,
8 may hit the knees of the operator. Also, the foot placed under the pedals 5, 6 may be pinched by the lever operation.

Since the pedals 5, 6 and the levers 7, 8 are arranged in a limited cab, their sizes are substantially determined, and the relationship between the operating force by the pedals 5, 6 and the operating force by the levers 7, 8 is also determined. It will be decided at the same time. Especially this lever
In the conventional pedal integrated type, the common load (pilot valves 3 and 4) is operated by the pedals 5 and 6 located closer to the fulcrum than the levers 7 and 8, so that the operating force by the levers 7 and 8 is reduced. Even if appropriate, there is a problem that the operation force by the pedals 5 and 6 becomes heavy.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to enable a traveling control of a construction machine to be properly performed by pedal operation and lever operation.

[0008]

Conceived of claim 1 SUMMARY OF THE INVENTION includes left and right pedals provided to be independent operation, independent Misao
Left and right levers operably provided and pilot valves for left and right pedals operated by left and right pedals respectively
And a pilot valve for left and right levers operated by the left and right levers, and a pilot valve for left pedal and
And the pilot valve for lever are connected to the inlet respectively.
Shuttle valve for left and pilot valve for pedal for right
Right where the inlets are connected to the pilot valve for lever and lever respectively
And the left shuttle valve outlet.
A travel control valve for the left, which is controlled by one of the pedal pilot valve and lever pilot valve for the left pedal pilot valves for the right is connected to the outlet of the shuttle valve and lever pilot valve for the right Neu Without
A travel control system for a construction machine having the configuration and a drive control valve for the right to be controlled by one or Re.

According to a second aspect of the present invention, in the configuration of the first aspect, there is provided a detecting means for detecting an operation by one of the lever and the pedal to generate a signal, and the other of the lever and the pedal switched by the detecting means. This is a traveling control device for a construction machine having a configuration in which a switching valve for stopping hydraulic pressure supply to an operated pilot valve is added.

[0010]

According to the first aspect of the present invention, since the pilot valve is arranged corresponding to each of the right lever, the right pedal, the left lever, and the left pedal, each can be operated independently. The lever does not operate when the pedal is operated, and the pedal does not operate when the lever is operated. Therefore, the knee is not hit with the lever when the pedal is operated, and the foot is not pinched by the pedal when the lever is operated.

According to a second aspect of the present invention, when one of the lever and the pedal is operated, the switching valve is switched by the detecting means, and the hydraulic pressure supply to the pilot valve operated by the other of the lever and the pedal is stopped. Since there is a circuit, the operation by one of the lever and the pedal can be prioritized to prevent confusion of the operation.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the embodiment shown in FIG.

Operating plates 31 and 32 are pivotally attached to the pedal pilot valves 33 and 34 on the brackets 11 and 12 by shafts 13 and 14 respectively. Operation plates 35 and 36 are pivotally attached to shafts 23 and 24 on the shafts 21 and 22, respectively.
Reference numerals 25 and 26 are attached to the operation plates 31, 32, 35 and 36, respectively, so that they can be operated independently.

Each of the pilot valves 33, 34, 37, and 38 is connected to a pilot pressure port Pi by a spool which is elastically pressed via a spring as each of the operation plates 31, 32, 35, and 36 swings. Hydraulic source S from port Pt communicating with T
This is a combination of two valves V1 and V2 for controlling the port Ps communicating with the port Ps.

A shuttle valve 41 and a shuttle valve 41 are provided between two pilot pressure ports Pi provided on the left pedal pilot valve 33 and two pilot pressure ports Pi provided on the same lever pilot valve 37, respectively. Pipeline 43 intervening 42,
The two shuttle valves 41, 42 are connected by the outlet 44, and the outlets of the two shuttle valves 41, 42 are communicated with the pilot pressure action parts 46, 47 at both ends provided on the left traveling control valve 45. Therefore,
The left traveling control valve 45 is supplied from the operated pilot valve of the pedal pilot valve 33 or the lever pilot valve 37 via the operated shuttle valve of the shuttle valves 41 or 42. Controlled by pilot pressure.

Similarly, a shuttle is provided between two pilot pressure ports Pi provided on the right pedal pilot valve 34 and two pilot pressure ports Pi provided on the same lever pilot valve 38, respectively. The two shuttle valves 51, 52 are connected by pipes 53, 54 which interpose valves 51, 52.
The outlet of 52 is connected to pilot pressure acting portions 56 and 57 at both ends provided in the right traveling control valve 55. Therefore, the traveling control valve 55 on the right side is the shuttle valve 51 or 52 from the operated pilot valve of the pedal pilot valve 34 or the lever pilot valve 38.
Is controlled by the pilot pressure supplied through the operated shuttle valve.

FIG. 1 shows a lever priority circuit.
The lever priority circuit includes, as lever operation detecting means for detecting the operation of the levers 25 and 26 and generating a signal, pipes 43 and 43 drawn from the pilot valves for levers 37 and 38, respectively.
Shuttle valves 61 and 44 between lines 44 and lines 53 and 54 respectively
62 is provided, and pilot lines 63 and 64 are drawn out from the outlets of the shuttle valves 61 and 62, respectively.

The pilot lines 63 and 64 are connected to pilot pressure operating portions 75 and 76 of switching valves 73 and 74 provided in the middle of hydraulic pressure source circuits 71 and 72 for the pilot valves 33 and 34 for the pedals.
It is connected to the. When the switching valves 73 and 74 are switched by the pilot pressure supplied from the lever pilot valves 37 and 38 via the shuttle valves 61 and 62, the switching to the pedal pilot valves 33 and 34 operated by the pedals 15 and 16 is performed. Stop the hydraulic supply.

Next, the operation of the embodiment shown in FIG. 1 will be described.

First, the basic operation will be described. Four pilot valves 33, 34, 37 and 38 respectively corresponding to the left and right pedals 15 and 16 and the left and right levers 25 and 26 are arranged. The parts can be operated independently. When the pedal is operated, the levers 25 and 26 are not operated, and when the lever is operated, the pedals 15 and 16 are not operated.

For this reason, the knees are not hit by the levers 25 and 26 when the pedals are operated. For example, when the right travel control valve 55 is operated, the right pedal 16 is depressed when the right pedal 16 is depressed.
Since only the 16 moves and the right lever 26 does not move, there is no danger of hitting the knee with the lever that can occur in the conventional example in which the lever moves simultaneously with the pedal. Similarly, pedals 15, 16
There is no danger of pinching the foot placed underneath.

Further, the priority of the levers will be described. Regardless of which side the levers 25 and 26 are operated, they are generated from one of the two valves V1 and V2 provided on the lever pilot valves 37 and 38, respectively. The pilot pressure is guided to the pilot pressure operating portions of the traveling control valves 45 and 55, and also guided to the pilot pressure operating portions 75 and 76 of the switching valves 73 and 74 via the shuttle valves 61 and 62, and the switching valves 73 and 74 are operated. Switch from the state of FIG. 1 to the opposite side. Then, the hydraulic pressure supplied to the pilot pilot valves 33, 34 from the hydraulic pressure source S via the switching valves 73, 74 is cut off, and the hydraulic pressure source circuits 71, 72 to the pedal pilot valves 33, 34 are disconnected. Since it is connected to the tank T, even if the pedals 15 and 16 are operated, the travel control valve
No hydraulic pressure is generated to operate 45 and 55. For example, pedal
Even if the levers 15 and 16 and the levers 25 and 26 are moved forward and backward,
Since only the direction can be moved by lever operation, always use pedal 1
The priority of levers 25 and 26 with respect to 5 and 16 is maintained.

The lever priority circuit can be changed to a pedal priority circuit by a simple circuit change. That is, the shuttle valves 61, 62 are connected to the travel control valves 45, 55.
The switching valves 73 and 74 are provided in a more pedal-side circuit.
Is provided in the middle of the hydraulic pressure source circuit for the lever pilot valves 37, 38, it becomes possible to detect the pedal operation and stop the hydraulic pressure supply to the lever pilot valves 37, 38.

[0024]

According to the first aspect of the present invention, a pedal is provided.
The pilot valve for the pedal operated by the
The pilot valve for the lever that is operated
Connected to a common travel control valve
No matter which pedal or lever you operate,
The control valves can be controlled in exactly the same way, that is, since one traveling control valve is independently controlled by two pilot valves corresponding to the pedal and the lever, pedal operation and lever operation can be performed independently, It is possible to prevent the lever from hitting the knee when the pedal is operated or the pedal from pinching the foot when the lever is operated.
In addition, the pilot valve itself has its own operating force characteristics, and the operating force and operating stroke of the pilot valve suitable for the operation of each pedal and lever can be set individually. The operating force can be made appropriate.

According to the second aspect of the present invention, one of the pilot valve for the pedal and the pilot valve for the lever has a priority. Therefore, even if the pedal and the lever are simultaneously operated, only one of the pilot valve and the lever has the priority. This has the effect of working and ensuring greater operational safety for the operator.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram of an embodiment showing a traveling control device of a construction machine of the present invention.

FIG. 2 is a hydraulic circuit diagram showing a conventional traveling control device for a construction machine.

FIG. 3 is an explanatory diagram showing a problem of the related art.

[Explanation of symbols]

 15, 16 Pedal 25, 26 Lever 33, 34 Pedal pilot valve 37, 38 Lever pilot valve 45, 55 Travel control valve 63, 64 Pilot line 73, 74 for detection means Switching valve

Continuation of the front page (72) Inventor Jun Yamakawa 1-3-2 Kitaaoyama, Minato-ku, Tokyo New Caterpillar Mitsubishi Corporation (56) References JP-A-51-45835 (JP, A) 48235 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) B62D 11/04

Claims (2)

(57) [Scope of request for utility model registration] 1. A left and right pedals provided to be independent operation
When the left and right levers provided so as to be independently operated, and the pilot valve pedal for the left and right that are operated respectively by the right and left pedals, and the lever for the pilot valve for the right and left to be operated respectively by the right and left levers, of for left Pilot valve for pedal and pilot for lever
Shuttle valve for left with inlet connected to each valve, pilot valve for pedal for right and pilot for lever
And the shuttle valve for the right inlet are connected respectively to the valve, for the left, which is controlled from <br/> to one of the pedal pilot valve and lever pilot valve for the left is connected to the outlet of the shuttle valve for left a travel control valve, and and a travel control valve for the right to be controlled from <br/> to one of the shuttle valve connected to the outlet pedal pilot valve and lever pilot valve for the right for the right A travel control device for a construction machine, comprising: 2. A detecting means for detecting an operation by one of a lever and a pedal to generate a signal, and a switching valve switched by the detecting means to stop supplying hydraulic pressure to a pilot valve operated by the other of the lever and the pedal. The travel control device for a construction machine according to claim 1, comprising: