JPS6019167Y2 - Float lock mechanism in the operating lever for lifting and lowering the backhoe - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a float lock mechanism in a lifting operation lever of a backhoe.

Backhoe work involves float work, where the main boom is set free to level the ground, etc., but when the control lever is moved to the float operation position to set the main boom free, the excavator is forced to move under its own weight. If the device falls suddenly and this is caused by erroneous operation of the operating lever, it is not only extremely dangerous, but also causes damage to various parts due to the impact of the fall.

This proposal was made in view of this problem, and it restricts lever operation to the float operation position during normal work.
This is intended to prevent unexpected accidents due to erroneous operation by interlocking with the foot pedal to release the restriction only when float work is required.

The present invention will be explained below based on embodiments shown in the drawings.

A is a backhoe equipped with excavator 1 and crawler 2.
A swivel base 4 is supported on a traveling machine base 3, and a driver's cabin 5 and a drive engine section 6 are provided on the swivel base 4.

The excavator 1 has a main boom 1a pivotably attached to the front end of a swivel base 4, an intermediate boom 1b pivotably attached to the tip of the main boom 1a, and a packet IC pivotably attached to the tip of the intermediate boom 1b. , main boom la, intermediate boom lb, and packet IC are hydraulic cylinders 1'a, , l'b, l'c, respectively.
The actuator rotates around the pivot point.

Reference numeral 7 denotes a lift operation lever provided in the driver's cab 5, and when operated in the left-right direction (direction of arrow a) and the front-back direction (direction of arrow mark), the hydraulic control valve is switched, and each of the above-mentioned hydraulic cylinders 1'a is operated. , l'b, l'c.

In this case, in FIG. 2, if the left side position is the operation position M of the intermediate boom 1b, the waist center position is the operation position C of the main boom 1a, and the right side position is the operation position B of the packet IC,
Each of the operation positions M, C, and B has a lowering operation position, a neutral position, and a raising operation position in the longitudinal direction, and the main boom operation position C has a lowering operation position 70 mm in front of the lowering operation position C-1.
One operation position C-2 is provided.

Note that C-0 is the neutral position C-3 at the main boom operating position C.
is the raised position.

Reference numeral 8 designates a link for valve operation that connects the arm 9 provided at the base end of the operating lever 7 and the spool 10' of the control valve 10 for the main boom. Link.

Reference numeral 11 denotes a stopper mechanism that restricts the lever operation from the lowering operation position C-1 to the float operation position C-2 when the operation lever 7 is set to the main boom operation position C, and is a stopper mechanism provided protruding from the link 8. It is composed of a stop pin 12 and a stopper rod 13 that comes into contact with the lower side of the stop pin 12 and restricts the downward movement of the link 8, that is, the forward lever operation of the operating lever 7.

In this case, by configuring the locking pin 12 and the stopper rod 13 to come into contact with each other when the operating lever 7 is operated to the lowering operation position C-1 of the main boom 1a, the operating lever 7 can be operated to lower the main boom 1a. Lever operation from position C-1 to float operation position C-2 is restricted.

The operating lever 7 moves from the lower operating position C-1 to the neutral position C-.
0, lever operation to the raised position C-3 is not restricted.

14 is a foot pedal provided at the foot of the operator, and the pressing operation of the foot pedal 14 is controlled by the stopper mechanism 1.
This is linked to the release operation in step 1.

Reference numeral 15 designates an interlocking mechanism between the foot pedal 14 and the stopper mechanism 11, in which an interlocking link 17 is connected to the other end of a stack 16 having the foot pedal 14 installed at one end, and the upper end of the interlocking link 17 is formed into a dogleg shape. Connected to one end of the stacking rod 18, and also connected to the letter-shaped stacking rod 1
8, the base end of the stopper rod 13 is connected to the other end of the guide tube 19, into which the stopper rod 13 is inserted.
is provided on the machine frame 20, and a tension spring 21 is provided at one end of the dogleg-shaped stacking rod 18 to urge the stopper rod 13 in the projecting direction while urging the foot pedal 14 upward.

Therefore, when the stopper rod 13 is held in the protruding state, the locking pin 12 comes into contact with the stopper rod 13 at the lowering operation position C-1 of the operation lever 7, and the float operation is performed from the lowering operation position C-1. Lever operation to position C-2 is restricted, and erroneous operation to float operation position C-2, which would cause the main boom 1a to fall suddenly, can be prevented.

When it is necessary to perform float work, after lowering the packet IC to the ground, the foot pedal 14 is pressed, and in conjunction with this pressing operation, the stopper rod 13 is moved backward, and the restriction by the stopper mechanism 11 is released. Then, the operating lever 7 is operated to the float operating position C-2.

As mentioned above, according to the present proposal, except for pressing the foot pedal and releasing the stopper mechanism linked to this, lever operation of the operation lever to the float operation position is reliably regulated, and unlike the conventional method, the operation of the lever is restricted to the float operation position. It is possible to safely perform backhoe work by preventing erroneous operation to a certain position, and there is no risk of damaging various parts of the backhoe by preventing a sudden impact of dropping the excavator due to erroneous operation.

[Brief explanation of the drawing]

FIG. 1 is an overall side view showing a backhoe according to an embodiment of the present invention, FIG. 2 is an explanatory plan view showing the operating position of an operating lever, and FIG. 3 is a side view showing a float lock mechanism of the present invention. A...Backhoe, 1...Shoe grinder, 1
a... Main boom, 7... Lifting operation lever, 11... Stopper! Structure, 12...
...Lock pin, 13... Stopper rod, 14.
...Foot pedal, C-1...Descent operation position, C-2...Float operation position.

Claims (1)

[Scope of utility model registration request] In order to operate the control valve 10 via the spool 10' which moves up and down by the forward and backward rotation of the operating lever 7, an arm 9 provided at the base end of the lever 7 and the spool 1 are connected to each other.
0' upper end through a link 8, and the link 8
A locking pin 12 is provided protruding from the locking pin 12, and a stopper rod 13 is provided below the locking pin 12 so as to be able to move forward and backward.
The locking pin 12 and The stopper rod 13 comes into contact with the main boom 1a, so that the lever operation from the lower operation position C-1 to the float operation position C-2 of the main boom 1a is always restricted, and the stopper rod 13 is moved backward by the pressing operation of the foot pedal 14. do,
A float lock mechanism configured to release contact with a locking pin 12.