JPH0540129Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field This invention relates to a hydraulic extraction device for a backhoe.

(b) Prior Art Conventionally, in order to supply hydraulic pressure from the hydraulic system installed in the backhoe to optional hydraulic equipment such as a hand hammer or hand breaker, a branch valve was installed in the hydraulic circuit a as shown in Fig. 9. A valve b was interposed so that hydraulic pressure was taken out from the end of a hydraulic pipe c branched at the same valve b.

(c) Problems to be solved by the invention However, when using the above-mentioned vibrating hydraulic equipment, the hydraulic pressure pulsates, and even though the return hydraulic pressure needs to be released smoothly into the reservoir. , Since the branch valve is interposed in the middle, the resistance of the return oil is large, which hinders the operation of the above equipment, and the hydraulic oil tends to overheat.Furthermore, the cross-sectional area of the oil passage inside the branch valve is Due to rapid changes,
Combined with the above-mentioned overheating, there were problems such as foaming of the hydraulic oil, and the complicated structure of the branch valve led to high costs.

(d) Means for solving the problem In this invention, a shutoff valve is interposed in the middle of the reciprocating hydraulic pipe that communicates the hydraulic actuator and the main hydraulic control valve, and the hydraulic cylinder of the excavation work section is A hydraulic outlet branched from each hydraulic pipe is interposed in the middle of the reciprocating hydraulic pipe between the shutoff valve and the main hydraulic control valve, and a hand hammer or hand breaker, etc. The present invention provides a hydraulic pressure extraction device for a backhoe, which is characterized in that it is connected to hydraulic equipment.

(E) Function/Effect According to this invention, there is no valve interposed between the hydraulic pressure outlet and the main hydraulic control valve, and therefore, the above-mentioned problems due to the interposition of the valve do not occur, and the option The hydraulic equipment can be operated satisfactorily, overheating and foaming of the hydraulic oil can be prevented, and the shutoff valve has a simpler structure and lower cost than a branch valve.

Furthermore, in the present invention, when operating a hydraulic device such as a hand hammer or a hand breaker, the hydraulic fluid flows to the hydraulic device without passing through the shutoff valve, so that it is not passed through the narrow flow path in the valve. Therefore, overheating and foaming of the hydraulic oil can be prevented, and the hydraulic equipment can operate smoothly.

(F) Example The example of the present invention will be explained in detail based on the drawings.
A shows a backhoe, in which a swing frame 2 is mounted above the running section 1 so as to be rotatable left and right.
A prime mover section 3 is mounted at the rear, a driving section 4 is mounted at the center, and an excavating section 5 is connected to the front end of the frame 2.

The prime mover section 3 is equipped with an engine 6 and a hydraulic pump 7 connected to the engine 6. Hydraulic pressure from the pump 7 is provided to the driving section 4, and hydraulic pressure is controlled by various operating levers 8 and operating pedals 9. It is controlled via the valve 10 to operate each hydraulic actuator disposed in the excavation work section travel section and the swing frame 2.

In particular, in the present invention, a swing hydraulic cylinder 11 for swinging the excavation work unit 5 left and right with respect to the revolving frame, and a shutoff valve 14 are provided midway through the reciprocating hydraulic pipes 12 and 13 between the main hydraulic control valve 10. branch pipes 15 and 16 are connected to the reciprocating hydraulic pipes 12 and 13 between the main hydraulic control valve 10 and the shutoff valve 14, respectively, and hydraulic pressure outlet ports 17 and 16 are provided at the tips of the branch pipes 15 and 16, respectively. A self-sealing type coupling as 18 is installed in series, and the same coupling 1 is installed.
Hydraulic pressure is supplied to optional hydraulic equipment via terminals 7 and 18.

In addition, 19 in the figure shows a swing pedal, and the operation of the pedal is transmitted to the main hydraulic control valve 10 via the linkage 20, and the swing hydraulic cylinder 11
21 indicates a stopper for the pedal 19, which temporarily fixes the pedal 19 in one operation position.

Therefore, by operating the shutoff valve 14, the reciprocating hydraulic pipe 1
When the hydraulic oil flow to the swing hydraulic cylinders 11 of 2 and 13 is cut off and the swing pedal 19 is fixed at one operating position with the stopper 21, the hydraulic pressure from the hydraulic pump 7 is transferred to the main hydraulic control valve 10 and the branch pipe 1.
5, 16 and oil pressure outlets 17, 18, it is possible to supply hydraulic pressure to optional hydraulic equipment, and in this case, a valve is interposed between the main hydraulic control valve 10 and the oil outlets 17, 18. Hydraulic pressure is supplied smoothly.

Note that the shutoff valve 14 has a check valve 2 on the shutoff side.
2 to ensure the shutoff of hydraulic pressure, and to recover oil leaking inside the valve 14 to the reservoir 23 via the return hydraulic pressure pipe 13.

In addition, the switching lever structure for operating the cutoff valve 14 is shown in FIGS. 3, 4, and 5.
25 is a lever for operating the excavation work unit 5, 26 is a switching lever, and the same lever 26 is connected to the operating stand 24.
A pivot 27 is inserted through the rear surface, the base end of the lever 26 is connected to the same shaft 27, and the middle part of the lever 26 is connected to the shaft 27.
A plate-shaped stopper spring 2 bent into a Z-shape
Each protrusion 3 is brought into contact with the rear side surface 29 of 8, and three protrusions 30a, 30b, and 30c are formed on the same side surface 29.
Switching lever 2 between 0a, 30b, and 30c
The position of the stopper spring 28 is made stable, and the pivot 27 is interlocked with the shutoff valve 14 by a link 31 to ensure that the operating position of the valve 14 is maintained.A name plate 32 is attached to the center of the stopper spring 28. This makes it easier to visually recognize the switching position of the lever 26.

6, 7, and 8 show the structure of the throttle lever 33, and the throttle lever 33 is inserted into a substantially square-shaped guide hole 35 cut out on the upper surface of the console 34.
A maximum rotation position 36 is provided at the front end of the hole 35, a stop position 37 is provided at the rear end of the hole 35, and an idling position 38 is provided at the bent portion of the hole 35. The tongue piece 4 at the top of the spring 40 can be tilted left and right around the pin 39 at the base end of the spring 40.
1 urges the lever 33 inward. Therefore, when the throttle lever 33 is operated to return from the maximum rotation position 36 to the idling position 38, the idling position 38 provided at the bent portion of the guide hole 35 is
to ensure a temporary stop, then move to stop position 3.
This prevents the engine from being stopped by operating the throttle lever 33 up to 7.

[Brief explanation of the drawing]

FIG. 1 is an overall side view of a backhoe having a hydraulic extraction device according to the present invention. Figure 2 is a hydraulic circuit diagram. FIGS. 3 to 8 are explanatory diagrams of other embodiments. 9th
The figure is a hydraulic circuit diagram of a conventional structure. 10...Main hydraulic control valve, 12, 13...Reciprocating hydraulic pipe, 14...Shutoff valve, 17, 18...Hydraulic pressure outlet.

Claims (1)

[Scope of Claim for Utility Model Registration] A cutoff valve 14 is interposed in the middle of the reciprocating hydraulic pipes 12 and 13 that communicate the hydraulic actuator and the main hydraulic control valve 10, and the hydraulic cylinder of the excavation work section 5 is Each hydraulic pipe 1 is connected in the middle of the reciprocating hydraulic pipes 12 and 13 between the shutoff valve 14 and the main hydraulic control valve 10.
A hydraulic pressure extraction device for a backhoe, characterized in that hydraulic pressure extraction ports 17 and 18 branched from 2 and 13 are interposed, and a hydraulic device such as a hand hammer or a hand breaker is connected to the hydraulic pressure extraction ports 17 and 18.