JPH0412122Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] This invention was made for the purpose of facilitating rearrangement work to change the working radius of construction machines such as hydraulic excavators that have an elevating boom. be.

[Prior Art] Construction machinery with an elevating boom, especially small hydraulic excavators, has a minimum turning radius R (fourth
In some cases, an even smaller turning radius R' (see Fig. 5) than that shown in Fig. 5 is required.

In order to meet this requirement, the position of the foot pin mounting hole of the boom cylinder 1 was changed to the standard position a.
and a small turning position b located diagonally above the foot pin, and the foot pin is moved to the standard position a as shown in Fig. 4 during normal work, and to the small turning position b as shown in Fig. 5 when necessary. It is known that the minimum turning radius can be changed from R to an even smaller R' by changing the radius to R'.

[Problem to be solved by this invention] However, it is not easy to change the mounting position of the foot pin of the boom cylinder 1, and one of the two workers must change the mounting position of the boom cylinder 1 from the driver's seat in the operator cab. The length of the cylinder must be adjusted by operating the operating lever, and the other person must check the position of the pin hole (a or b) on the ground and insert the pin. There is a problem in that it requires workers, and if there is poor cooperation between the workers, the work will not proceed smoothly.

In addition, if there is only one worker, the pin hole positions a and b cannot be clearly seen from inside the operator's cab, so the worker must repeatedly get in and out of the cab through trial and error and operate the cab from the operator's seat. There is a problem in that the boom cylinder 1 must be extended and retracted by operating a lever, and then the operator must go down to the ground to align the pin holes and insert the pins, which requires a great deal of labor.

This invention was made with the aim of solving the above problems.

[Means for Solving the Problems] This invention provides a means for solving the problems described above, in which the foot pin mounting hole of the boom cylinder 1 is arranged in a standard position a and a small swing position b located diagonally above the standard position a. The foot pin of the boom cylinder 1 can be selectively changed between the standard position a and the small turning position b. A construction machine characterized in that another operating lever 8b is detachably attached to the operating control link 4 of the control valve 1a of the boom cylinder 1, and the boom cylinder 1 can be operated from the ground by the operating lever 8b. The gist of this invention is a working radius changing device.

[Operation] Since this device has the above configuration,
As is known, normally, by tilting the operating lever 8a in the driver's cab, the control link 4 located at the bottom of the vehicle body is rotated, thereby operating the control valve 1a and raising or lowering the boom. However, when changing the mounting position of the foot pin of the boom cylinder 1, by attaching the removable operating lever 8b to the control link 4, the operating lever 8b can be tilted not only from inside the operator's cabin but also on the ground. By directly rotating the control link 4 and operating the control valve 1a, the boom cylinder 1 can be expanded and contracted, and the foot pin of the boom cylinder 1 can be installed at the standard position a.
The operation of changing from the position to the small turning position b (or vice versa) can be easily performed.

[Example] The embodiment shown in the drawings will be described.

In the figure, reference numeral 1 denotes a boom cylinder for raising and lowering the boom, which expands and contracts by supplying and discharging pressure oil by operating a control valve 1a, and can raise and lower the boom.

Reference characters a and b indicate the positions of the foot pin attachment holes of the boom cylinder 1, which are provided diagonally at the front of the lower part of the vehicle body.

A is a standard position, b is a small turning position located diagonally above the standard position, and the foot pin is moved to the standard position a as shown in FIG. By changing to position b, the minimum turning radius can be changed from R to an even smaller R'.

Reference numeral 2 designates an operating rod of the control valve 1a, the rod end 3 of which is connected by a pin to an arm 4a that projects vertically from a control link 4.

The control link 4 has a cylindrical shape and is rotatably supported by a pin shaft 5 fixed horizontally at the bottom of the vehicle body, and an arm 4 projecting horizontally.
b, and is adapted to be interlocked with an operating lever 8a inside the driver's cab via a link 6 and a joint 7. In the figure, 10 indicates a driver's cab, 11 indicates a platform, and 12 indicates a safety belt.

When the operator tilts the operating lever 8a in the driver's cab 10 from the neutral position in the A direction (toward the front), the link 6 moves upward in the A direction about the horizontal shaft built into the joint 7, and the arm 4b moves counterclockwise. Rotate to. Therefore, the control link 4 rotates counterclockwise around the pin 5, and the arm 4a
also rotates counterclockwise, so the operating rod 2 is
move in the direction.

Further, when the operator tilts the operating lever 8a in the B direction (forward), the operating rod 2 similarly moves in the B direction. In this way, by operating the operating lever 8a in the operator's cab, the control valve 1a can be operated to extend or contract the boom cylinder 1.

The above is well known, but in the present invention, the control link 4 is
In addition to the arms 4a and 4b, a third arm 4c is provided to protrude in any direction (vertical direction in this embodiment), and a removable operating lever 8b is attached to the arm 4c by a butterfly bolt 9. I'm starting to be able to do it.

Therefore, as shown in FIG.
If this is installed, the control link 4 can be rotated by operating the operating lever 8b on the ground without using the operating lever 8a in the operator's cab, so the mounting position of the foot pin of the boom cylinder 1 can be changed to a. to b (or vice versa)
When changing from (a) to (a), the operator exits the operator's cab, descends to the ground, and easily extends and retracts the boom cylinder 1 while visually checking the mounting hole positions (a, b) on the ground as shown in Figure 3. The position can be adjusted to

[Effect] According to this invention, the foot pin mounting holes of the boom cylinder 1 are provided at two locations, the standard position a and the small swing position b located diagonally above the standard position a, and the foot pin mounting holes of the boom cylinder 1 are set at the standard position a and the small swing position b located diagonally above the standard position a. In addition, another control lever 8b can be attached and detached from the control link 4 for operating the control valve 1a, which is located at the bottom of the vehicle body and interlocks with the control lever 8a in the driver's cab. The operating lever 8 can be freely moved.
By making it possible to operate the boom cylinder 1 from the ground using b, the work to change the mounting position of the foot pin of the boom cylinder 1, which conventionally required the cooperation of two workers: the driver and a ground worker. of,
This can be done by one worker, and the boom cylinder 1 can be expanded and contracted while visually checking the mounting hole positions (a, b) on the ground, making it easy to align the foot pin and the mounting hole. This has the effect of making it easy to carry out.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a perspective view of the operating system, Fig. 2 is a view taken in the direction of arrow A in Fig. 3, Fig. 3 is a perspective view showing the working state, and Figs. 4 and 5. FIG. 3 is an explanatory diagram showing changes in the minimum turning radius. 1... Boom cylinder, 1a... Control valve, 2... Operation rod, 3... Rod end, 4... Control link, 5... Pin shaft,
6...Link, 7...Joint, 8a...Control lever (inside the driver's cab), 8b...Control lever (from the ground), 9...Butter bolt, 10...Driver's cab,
11...Platform, 12...Safety belt,
a...Foot pin mounting hole standard position, b...
Foot pin mounting hole small turning position.

Claims (1)

[Scope of utility model registration request] Foot pin mounting holes of the boom cylinder 1 are provided at two locations, a standard position a and a small swing position b located diagonally above the standard position a, and the boom cylinder 1
The mounting position of the foot pin can be selectively changed between standard position a and small turning position b, and is for operating the control valve 1a of the boom cylinder, which is located at the bottom of the vehicle body and interlocks with the operating lever 8a in the driver's cab. A working radius changing device for construction machinery, characterized in that another operating lever 8b is detachably attached to the control link 4, and the boom cylinder 1 can be operated from the ground using the operating lever 8b.