JPH06200775A - Construction machine - Google Patents

Abstract

PURPOSE:To integrate various functions and reduce the cost by integrating a remote control valve pump and a cutoff valve concurrently having the cutting function and adjusting function of the pressure oil to a remote control valve, and arranging it on the crank axis of an engine. CONSTITUTION:A construction machine, e.g., a back hoe, is arranged with a hydraulic control valve mechanism B below a seat and an engine E in an engine room at the rear section of a machine body. The engine E is arranged with a radiator 11 on one side and a pump mechanism A on the extension of a crank shaft on the other side. A swivel joint 12 is arranged at the center of a rotary frame F, and a boom bracket 13 rotated by a swing cylinder 14 is arranged at the front section of the machine frame. A cutoff valve V concurrently having the cutting function and adjusting function as a relief valve of the pressure oil to a remote control valve is integrally fixed at the upper section of a remote control valve pump P connected to the portion of the pump mechanism A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an arrangement of a cut-off valve attached near an engine and a structure of an engine undercover below an oil drain plug of an engine in a construction machine such as a backhoe.

[0002]

2. Description of the Related Art Conventionally, in a construction machine such as a backhoe, a technique of cutting a supply of pressure oil to a remote control valve and providing a cut-off valve having a relief function for adjusting the pressure is known. is there. However, the conventional cutoff valve is arranged at a position distant from the engine and is connected by a hydraulic hose. An engine undercover is arranged below the engine of a construction machine such as a backhoe.
There was an opening so that the oil drain plug of the engine could be opened and closed.

[0003]

The present invention requires a hydraulic hose, a joint, and a mounting bracket, which have been conventionally arranged separately, and a special mounting space for the cutoff valve. , Is integrally arranged on the upper part of the pump for the remote control valve to reduce the cost and improve the maintainability. Further, since noise leaks to the outside from an opening provided in the engine under cover below the oil drain plug of the engine, an opening / closing lid and a hermetic seal are provided in order to prevent noise from being generated from this portion. .

[0004]

The problems to be solved by the present invention are as described above. Next, the means for solving the problems will be described. That is, a pump P for a remote control valve that supplies pressure oil to the remote control valve, a function of cutting the pressure oil to the remote control valve, and a cutoff valve having a function of a relief valve that adjusts the pressure for the remote control valve. Are integrated and arranged on the axis of the crankshaft of the engine.

Further, in the engine undercover arranged at the bottom of the engine compartment, an opening / closing lid for closing the opening below the oil drain plug of the engine is provided, and the periphery of the oil drain plug is closed by a hermetic seal.

[0006]

[Operation] Next, the operation will be described. That is, the functions of the remote control valve pump P and the cutoff valve V can be integrated, and the cost can be reduced. Further, the mounting bracket for the cutoff valve V, which is conventionally provided, is no longer required. Further, although the pump mechanism A is provided with the cut-off valve V, the pump mechanism A can be compactly housed inside the engine compartment, so that maintainability is improved. Further, conventionally, the noise leaked from the opening 23 opened in the engine undercover 10 was eliminated, and the noise could be further reduced. Further, since the oil drain plug 7 can be removed by removing the opening / closing lid 9, maintainability is not deteriorated.

[0007]

EXAMPLES Next, examples will be described. 1 is a plan view showing the inside of the engine room of the backhoe of the construction machine and the state of hydraulic piping, FIG. 2 is a plan view of the pump mechanism portion arranged on the extension of the clan shaft of the engine E, and FIG. 3 is the same as the pump mechanism. Front view, FIG. 4 is a side view of the pump mechanism,
FIG. 5 is a side sectional view of a part where the remote control valve pump P and the cutoff valve V are integrated, FIG. 6 is a plan sectional view of the cutoff valve V arranged above the remote control valve pump P, and FIG. It is a side view of the pump P for remote control valves, and the cutoff valve V.
FIG. 8 is a hydraulic circuit diagram of the remote control valve pump P and the cutoff valve V.

Referring to FIG. 1, the inside of the engine room of the backhoe of the construction machine and the state of hydraulic piping will be described. A hydraulic control valve mechanism B is arranged under the seat of the backhoe. An engine is located inside the engine compartment at the rear of the machine. Radiator 11 on one side of engine E
Is arranged, and the pump mechanism A is arranged on the other side of the engine E on the extension of the crankshaft. A swivel joint 12 is arranged at the center of the swing frame F, and a boom bracket 13 rotated by a swing cylinder 14 is arranged at the front part of the machine body. In the present invention, the cut-off valve V, which is conventionally arranged by providing a bracket in front of the hydraulic control valve mechanism B, is integrally fixed to the upper portion of the remote control valve pump P which is connected to the pump mechanism A portion. Of.

Next, the construction of the pump mechanism A will be described with reference to FIGS. 2, 3 and 4. In the pump mechanism A, four hydraulic pumps are driven by the pump shaft 19. The pump shaft 19 is connected to the crankshaft of the pump mechanism A. The four pumps constituting the pump mechanism A include a rotary piston pump 17 that supplies pressure oil to the left traveling motor, swing cylinder, and arm cylinder, and pressure oil to the right traveling motor, bucket cylinder, and boom cylinder. A rotary piston pump 18, a gear pump 16 that supplies pressure oil to a blade cylinder and a swing hydraulic motor, and a remote control valve pump P that constitutes a main part of the present invention. The rotary piston pumps 17 and 18, the gear pump 16, and the remote control valve pump P are connected to each other. The rotary piston pump 17 is located closest to the engine E, and the remote control valve pump P is located farthest from the engine E. Has become.

In the present invention, the cut-off valve V is mounted on the upper surface of the pump case 1 of the remote control valve pump P constituted by the gear pump in the above structure. This will be described with reference to FIGS. 5, 6 and 7. The remote control valve pump P is composed of a steering lever 1 and two pump gears 2 in mesh with each other. The pressure oil protruding from the remote control valve pump P is directly supplied to the pump port Po of the cutoff valve V.

In the cutoff valve V, a cutoff spool 3 and a relief valve 4 are arranged inside a valve case 6. A solenoid actuator SO is arranged on one side of the valve case 6, and the cutoff spool 3 is configured to slide in the opening / closing direction by energizing the solenoid actuator SO.
The cut-off valve V is a remote control device that disables the operation lever operation when a dangerous condition may occur, such as when the aircraft is stopped or the engine is stopped. The pressure oil from the control valve pump P to the pilot valve is cut off. Since the cutoff valve V does not supply pressure oil to the pilot valve, it is impossible to switch the working machine operation valves by the pressure oil of the pilot valve, and the bucket, arm, boom, blade, and traveling motor are operated. It will be impossible.

FIG. 9 is a rear sectional view of the engine compartment, FIG. 10 is a side sectional view of the engine compartment, FIG. 11 is a side view of the opening / closing lid 9 and the hermetic seal 8, and FIG. 13 is a side cross-sectional view showing another embodiment of the hermetic seal 8 when the oil drain plug 7 is arranged on the side surface of the oil pan 20, and FIG. It is a side sectional view showing a drain discharge state from the oil drain plug 7.

In FIG. 9, an engine compartment cover 22 is arranged on the revolving frame F. An engine under cover 10 is attached to the bottom of the revolving frame F and closed at the bottom of the engine compartment to prevent noise of the engine E from leaking from below. However, the lower surface of the oil pan 20 of the engine E is provided with an oil drain plug 7 for replacing dirty lubricating oil, and the engine under cover 10 is provided with the oil drain plug 7 for opening and closing the oil drain plug 7. Has an opening 23.

In conventional construction machines such as backhoes, noise was generally large, so that the degree of noise leaking from the opening 23 did not pose a serious problem.
However, recently, the airtightness of the engine room is improved, and the leakage of the noise of the engine E is completely prevented at each part, so that the leakage of the noise from the opening 23 for the oil drain plug 7 also becomes a problem. Has changed to. In the present invention, in order to meet this demand, the opening / closing lid 9 is attached to the opening 23 of the engine undercover 10, and the opening / closing lid 9 is provided.
A hermetic seal 8 is attached to the periphery of the.

In the embodiment of FIGS. 13 and 14, the oil drain plug 7 is opened on the side surface of the oil pan 20, so that the auxiliary plate 21 is projected from the engine undercover 10 and the auxiliary plate 21 is provided. A hermetic seal 8 is arranged between the oil pan 20 and the oil pan 20. The point that the opening 23 is closed by the opening / closing lid 9 is the same. Further, as shown in FIGS. 11 and 12, the hermetic seal 8 may be fixed to the side of the opening / closing lid 9, and the opening 23 ′ may be always opened in the opening / closing lid 9. Even if the opening 23 ′ is always opened, the noise can be shielded by the hermetic seal 8, so that the noise leaked to the outside can be reduced.

[0016]

Since the present invention is constructed as described above, it has the following effects. That is, as in claim 1,
A remote control valve pump P for supplying pressure oil to the remote control valve,
Since a cut-off valve having a function of cutting pressure oil to the remote control valve and a function of a relief valve for adjusting the pressure for the remote control valve is integrally configured and arranged on the axis of the engine crankshaft, The functions of the remote control valve pump P and the cutoff valve V can be integrated, and the cost can be reduced. Moreover, the mounting bracket for the cut-off valve V, which is conventionally provided, is no longer necessary. Further, the pump mechanism A has a cutoff valve V
Despite being attached, it can be stored compactly inside the engine compartment, improving maintainability.

According to a second aspect of the present invention, in the engine undercover arranged at the bottom of the engine compartment, an opening / closing lid for closing the opening below the oil drain plug of the engine is provided, and the periphery of the oil drain plug is closed by a hermetic seal. Therefore, it is possible to further reduce the noise by eliminating the problem that noise has leaked from the opening 23 formed in the engine undercover 10 in the related art. Further, since the oil drain plug 7 can be removed by removing the opening / closing lid 9, maintainability is not deteriorated.

[Brief description of drawings]

FIG. 1 is a plan view showing the inside of an engine room of a backhoe of a construction machine and a state of hydraulic piping.

2 is a plan view of a pump mechanism portion arranged on an extension of a clan shaft of an engine E. FIG.

FIG. 3 is a front view of the pump mechanism.

FIG. 4 is a side view of the pump mechanism portion.

FIG. 5 is a side sectional view of a portion where a remote control valve pump P and a cutoff valve V are integrated.

FIG. 6 is a plan cross-sectional view of a cutoff valve V arranged on an upper portion of a remote control valve pump P.

FIG. 7 is a side view of a remote control valve pump P and a cutoff valve V.

FIG. 8 is a hydraulic circuit diagram of a remote control valve pump P and a cutoff valve V.

FIG. 9 is a rear cross-sectional view of the engine compartment.

FIG. 10 is a side sectional view of the engine compartment of the same.

11 is a side view of the opening / closing lid 9 and the hermetic seal 8. FIG.

FIG. 12 is a side sectional view of an opening / closing lid 9 and a hermetic seal 8.

13 is a side sectional view showing another embodiment of the hermetic seal 8 when the oil drain plug 7 is arranged on the side surface of the oil pan 20. FIG.

FIG. 14 is a side cross-sectional view showing a drain discharge state from an oil drain plug 7 provided on a side surface of an oil pan.

[Explanation of symbols]

 A pump mechanism B hydraulic control valve mechanism P remote control valve pump V cutoff valve 1 control lever 7 oil drain plug 8 hermetic seal 9 open / close lid 10 engine undercover 23 opening

Claims (2)

[Claims] 1. A cut having a remote control valve pump P for supplying pressure oil to the remote control valve, a function of cutting the pressure oil to the remote control valve, and a relief valve function of adjusting the pressure for the remote control valve. A construction machine characterized in that an off valve is integrally formed and arranged on the axis of the crankshaft of the engine. 2. An engine undercover arranged at the bottom of an engine compartment, wherein an opening / closing lid for closing an opening below an oil drain plug of the engine is provided, and the periphery of the oil drain plug is closed by a hermetic seal. Construction machinery.