JPH04237724A - Work vehicle travel linkage device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work vehicle such as a backhoe or a crane truck, that is, a work vehicle in which a work device is driven and operated while the traveling body is stopped.

0002

[Prior Art] The above-mentioned work vehicle has a traveling operation tool for traveling,
Separate operating tools are provided for each work device, and when the engine is running, both operating tools are
Both are in use.

[0003] Therefore, when the engine is driven, it is possible to drive the traveling device, move the working device, or drive both at the same time.

0004

[Problems to be Solved by the Invention] However, in the above-mentioned work vehicle, in reality, the work device and the traveling device are rarely driven at the same time, and on the contrary, if the work device is driven while moving, the balance of the machine will be lost. This is undesirable because there is a risk that the work equipment may easily roll over or the work equipment may come into contact with other objects.

[0005] Therefore, although both operating tools are not normally operated at the same time, there is a possibility that the operating tool of the working device may be accidentally moved while the user is moving by hooking it with the arm, so some kind of improvement is required. It was wanted.

[0006] An object of the present invention is to avoid the above-mentioned inconvenience while providing separate operation tools for the traveling device and the working device.

[0007]

[Means for Solving the Problems] To achieve the above-mentioned object, the present invention provides that when a travel operating tool that controls running and stopping of a traveling aircraft is operated to a traveling position that reveals the traveling state of the traveling aircraft, The present invention is characterized in that a travel linkage device is configured by providing a check mechanism that links the travel operating tool and the drive device of the work device in a state where the drive of the installed work device is checked and prevented.

[0008]

[Effect] Due to the function of the restraint mechanism, the work equipment will not move even if the operating tool of the work equipment is operated while the machine is moving, which may cause the machine to lose its balance and easily overturn, or the work equipment to come into contact with other objects. The fear of this will be resolved.

[0009]Furthermore, if the operating tool of the traveling device is operated while the working device is being driven, the working device is immediately stopped by the check mechanism, so even in this case, the working device cannot be driven while traveling. can be avoided.

0010

Therefore, according to the structure of claim 1, even if an unexpected operation of the operating tool such as accidentally hooking the operating tool of the working device occurs while the vehicle is traveling, the working device will not move. It has been possible to provide a traveling linkage device that is preferable from the viewpoint of safety and can prevent both operating tools from being operated at the same time against one's intention.

[0011] In the traveling linkage device according to claims 2 and 3, even when the check mechanism is in operation, the movement operation of the operating tool of the working device itself is allowed, so the movement operation itself is disabled and the check mechanism is activated. This is advantageous in that, for example, there is no need to forcibly move the operating tool of the working device without knowing the operation of the check mechanism, and there is no risk of damage to the operating tool.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS A case where an embodiment of the present invention is applied to a backhoe, which is an example of a working vehicle, will be described below with reference to the drawings. FIG. 3 shows a small swing type backhoe equipped with an excavation device A, and FIG. 1 shows its operating system. This backhoe includes a cross operation lever 5 that operates the control valve 2 for the boom cylinder 1 and the control valve 4 for the bucket cylinder 3, a control valve 7 for the arm cylinder 6, and a control valve 9 for the swing motor M of the swing base 8. Traveling levers 14, 14 are provided, each having a cross operation lever 10 to be operated, and operating control valves 13, 13 for the motors 12, 12 of the left and right crawler traveling devices 11, 11, respectively. The reference numeral 19 denotes a hydraulic pump, and the hydraulic system configured as described above serves as a drive device B for the working device A.

Each of the control valves 2, 4, 7, and 9 for the working device A is configured as an electromagnetic control valve, and is electrically operated via a controller 15 by joystick-type cross operation levers 5, 10. Each travel lever 14 is configured to operate the control valve 13 by a mechanical linkage mechanism.

As shown in FIG. 1, limit switches 16, 16 are provided which are configured to be turned on and off by rods 24 that are linked to the lever operation of each travel lever 14, and these limit switches 16, 16 and the controller 15 are connected to each other. are electrically connected.

Each limit switch 16 is connected to the travel lever 14.
It is set to be turned on at forward and reverse positions F and R, and turned off at neutral position N where travel stops, and when at least one of the limit switches 16 is turned on, the control for excavation work equipment A is set. The controller 15 functions in such a state that no operation current flows through the valves 2, 4, 7, and 9 according to the output signals of the cross operation levers 5 and 10, and thereby the drive of the working device A is checked and prevented while the vehicle is running. A restraining mechanism 17 is configured.

[Another embodiment] As shown by the virtual line in FIG.
A changeover switch 20 is provided that connects and disconnects the connection wiring 18 between the cross operation levers 5 and 10 and the controller 15, and when at least one travel lever 14 is operated, both the changeover switches 2
The check mechanism 17 may be configured to switch both of 0 and 20 to the side where conduction is interrupted.

Furthermore, as shown in FIG. 2, if the control valve for the boom cylinder 1 is a control valve 22 operated by pilot pressure from a pilot valve 23, the pilot circuit The check mechanism 17 may be constructed by mechanically (or electrically) interlocking the switching valve 21 provided at L so as to switch the switching valve 21 to cut off the hydraulic pressure supply to the pilot valve 23 of the cross operation lever 5, 10. .

[0018] Furthermore, a check mechanism is provided that prevents the travel drive when the operating tool of the work device is operated to the drive position, so that the machine does not start moving even if the travel lever is unexpectedly operated during work. It is even more preferable if

It should be noted that although reference numerals are written in the claims for convenience of comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

[Figure 1] Circuit diagram of travel linkage device

[Figure 2] Hydraulic circuit diagram of pilot operating system

[Figure 3] Side view of backhoe

[Explanation of symbols]

1 Hydraulic cylinder 2 Control valve 14　Traveling operation tool 15 Controller 17 Check mechanism 19 Hydraulic pump 21　Switching valve 22 Pilot type control valve A Work equipment B Drive device

Claims (3)

[Claims] Claim 1: As the traveling operation tool (14) that controls the traveling and stopping of the traveling machine body is operated to the traveling position where the traveling state of the traveling machine body is displayed, the installed working device (A) is driven. The travel operating tool (14) is in a state where it is checked and prevented.
A traveling linkage device for a working vehicle, which is provided with a check mechanism (17) that links the drive device (B) of the working device (A) with the drive device (B) of the working device (A). 2. The working device (A) is a backhoe excavating device, and the driving device (B) includes a hydraulic cylinder (1) for driving the excavating device and an electromagnetic control valve (1) for driving the excavating device.
2) and a hydraulic pump (19), and includes a controller (15) for switching the electromagnetic control valve (2) by moving an operating lever (5), and a controller (15) for switching the electromagnetic control valve (2). 17) to the travel operating tool (14).
2. The traveling linkage device for a working vehicle according to claim 1, further comprising means for disabling output from the controller (15) to the electromagnetic control valve (2) when the controller (15) is operated to the traveling position. 3. The working device (A) is a backhoe excavating device, and the driving device (B) includes a hydraulic cylinder (1) for driving the excavating device, a pilot type control valve (22) thereof, and a hydraulic cylinder (1) for driving the excavating device. It is a hydraulic device composed of a pump (19), which controls the check mechanism (17) to apply pilot hydraulic pressure to the pilot type control valve (22) when the travel operation tool (14) is operated to the travel position. 2. The traveling linkage device for a work vehicle according to claim 1, further comprising means for operating a switching valve (21) for disabling the occurrence of such a change.