JPS598053Y2 - Hydraulic switching valve operating device for hydraulic work equipment - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an operating device for a hydraulic switching valve in a hydraulic working machine.

In hydraulic work machines such as hydraulic truck cranes and civil engineering machinery, operators operate many hydraulic actuators, and these hydraulic actuators are generally spring-type actuators operated by manually operated levers. Since it is controlled by an offset type hydraulic switching valve, the operator can operate two hydraulic actuators at the same time, but cannot operate three or four hydraulic actuators at the same time.

The present invention provides a new operating device in which a spring offset type hydraulic switching valve operated by a manual operating lever can be locked and unlocked at any operating position by operating a foot pedal. The purpose is to achieve simultaneous operation of four hydraulic actuators and improve the work efficiency of a hydraulic working machine.

Embodiments of the present invention will be described in detail below with reference to the drawings.

In FIG. 1, 1 is a driver's seat of a hydraulic working machine, 2 is a floorboard of the driver's seat, and 3 is a manual operation lever whose fulcrum part is pivoted 4 on a floorboard 2 in front of the driver's seat 1.

Reference numeral 5 designates a spring center type hydraulic switching valve disposed below the driver's seat 1 and below the floorboard 2.

The spool 6 of the hydraulic switching valve 5 is connected to the arm 8 of the manual operation lever 3 via a connecting rod 7.

When the manual operating lever 3 is operated, its movement is such as to move the connecting rod in the axial direction and actuate the spool 6 of the spring center type hydraulic switching valve 5.

9 is an engagement piece provided on the connecting rod 7.

Reference numeral 12 denotes a rod 13 that is slidably inserted into the floorboard 2 in the vertical direction.
This is a pedal placed at the top end of the .

A stopper 14 is attached to the lower end of the rod 13, and this stopper 14 is arranged at a corresponding position on the locking piece 9 so as to engage with the locking piece 9 when the pedal 12 is depressed.

A spring 15 is interposed between the floor plate 2 and the pedal 12 to bring the stopper 14 to a position where it does not engage with the retaining piece 9 when the pedal 12 is not depressed.

The retaining piece 9 has two inclined engagement surfaces 10 and 11 that are inclined with respect to the moving direction of the stopper 14.

Next, the action will be explained.

When the operator operates the manual operation lever 3 in the direction A in FIG. Step in.

Then, the stopper 14 moves downward and engages with the inclined retaining surface 10 of the engagement piece 9, thereby restricting the return movement of the hydraulic switching valve 5 in the direction toward the opening.

If you operate the manual operation lever 3 in the direction of the opening in Figure 1 to move the spring center type hydraulic switching valve 5 in the direction of the opening, and try to hold the hydraulic switching valve 5 in this operated state, the pedal should be pressed in the same way. Step on 12.

Then, the stopper 14 moves downward and engages with the inclined engagement surface 11 of the retaining piece 9, thereby restricting the return movement of the hydraulic switching valve 5 in the direction A'.

The inclined engagement surfaces 10 and 11 are arranged so that the pedal 12 increases as the amount of operation of the hydraulic switching valve 5 in the A' direction or the OUT' direction increases.
This function requires a large amount of depression of the pedal 12, and the amount of depression of the pedal 12 is gradually reduced from the state in which the hydraulic switching valve 5 is operated in the A' direction or the ENT direction and held as described above. Thus, the hydraulic pressure switching valve 5 can be slowly returned to its original state.

Of course, it is also possible to suddenly return the hydraulic switching valve 5 by suddenly releasing the pedal 12.

In the above embodiment, the inclined retaining surface 10 is located on the retaining piece 9 side.
11, but as shown in FIG. 2, an inclined engagement surface 10'. 11' may be provided, and of course, the retaining piece 9 may be provided with an inclined engagement surface 10.11, and the stopper 14 may be provided with inclined engagement surfaces 10' and 11'. .

Since the present invention is structured and operates as described above, the spring offset type hydraulic switching valve can be held in any operating position by the foot pedal, so the operator can operate one or two spring offset type hydraulic switching valves. Other manual operating devices can be manually controlled while the hydraulic switching valve is kept in the operating state, and the return operation of the hydraulic switching valve held in the operating state by the pedal can be arbitrarily controlled by adjusting the speed at which the pedal is released. It is possible to greatly improve the working efficiency of hydraulic working machines.

[Brief explanation of the drawing]

FIG. 1 is an embodiment diagram in which the operating device for a hydraulic switching valve in a hydraulic working machine according to the present invention is implemented in a spring center type hydraulic switching valve. Figures 2 and 3 show the retaining piece 9 in Figure 1.
FIG. 3 is an explanatory diagram showing a modified example of the stopper 14. Manual operation lever; 3, Hydraulic switching valve; 5, Connection rod; 7
, Engagement piece; 9, Depressing pedal; 12, Stopper; 1
4. Inclined engagement surface; 10, 11, 10', 11'.

Claims (1)

[Scope of utility model registration request] An engaging piece 9 is provided on the connecting rod 7 that transmits the movement of the manual operation lever 3 as an axial movement to the spring-offset type hydraulic switching valve 5, and an engaging piece 9 is provided at a position opposite to the retaining piece 9, which is not normally maintained. A stopper 14 is provided, which is brought to a position where it engages with the engaging piece 9 when the treadle pedal 12 is depressed, and when the treadle pedal 12 is depressed while the hydraulic pressure switching valve 5 is operated by the manual operation lever 3, the hydraulic pressure is adjusted. In a device configured to lock the switching valve 5 in the operating position, at least the stopper is configured such that the larger the operating amount of the hydraulic switching valve 5 is, the more the stopper 14 engages with the retaining piece at the greater depression position of the pedal 12. 14
and an inclined retaining surface 10 on either one of the retaining pieces 9. 11. An operating device for a hydraulic switching valve in a hydraulic working machine, characterized in that: 11 is provided.