JPH06294146A - Turning base structure for back hoe - Google Patents

Abstract

PURPOSE:To connect a large-sized return hose to an engine part without an exclusively designed installation space by a simple modification which forms an engine frame with a pipe material and comtribute to a further attempt to compact a turning base by promoting multifunctioning of components. CONSTITUTION:A boom is connected to a middle point between left and right sides of the front of a turning base 4. An operating part 7 is installed to the left side while an operating oil tank 10 installed to the other side respectively. A prime mover part B is installed to the rear side of the turing base 4. An sngine E of the prime mover part B is loaded on an engine frame 14c on the front side which extends to the left and right sides in the rear side of the turning base 4. a sareg-sized return bose 18 which connects an operation control vale V installed to the operating part 7 to the operating oil tank 10 is installed by way of an internal space of the engine frame 14c. Three hoses for pressure oil supply are clamped with a transverse partitioning wall 19 vertically in three rows.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backhoe swivel structure, and more particularly to a technique for rationally laying out various devices in a driving part.

[0002]

2. Description of the Related Art As shown in Japanese Utility Model Laid-Open No. 4-33757, a small swivel type backhoe has a swivel structure in which a driving part such as an engine is arranged at the rear of the swivel and a fuel tank and an operating member are provided on the right side. Generally, an oil tank or the like is arranged to balance the weight of the front, rear, left and right and to effectively use the space.

[0003]

The small turning type backhoe is capable of turning in a small radius and excellent in workability in a narrow space depending on the retracted posture of the boom by bending the boom. In order to further extend its advantage, it is also necessary to promote the downsizing of the swivel itself. As for the structure of the swivel base, the control part is on the left of the front part of the swivel, the tanks are on the right, the boom connecting parts are located in the middle of the left and right, and the engines are arranged on the rear part, and they are deeply intruded rear The boom connecting part, which serves as a part, separates the tank part from the control part. However, since an unexpectedly large installation space is required for the oil passage that connects the control valve group in the control section and the hydraulic oil tank in the tank section, it is necessary to bypass the boom connecting section and pipe through the engine section. Is convenient. However, in the swivel base, mechanical devices such as an engine and a radiator, which are rather bulky, are arranged without waste, and hydraulic hoses are piped in a state of sewing the gaps between them. It is predicted that even the gap cannot be secured. An object of the present invention is to further reduce the size of the swivel base by piping the hydraulic hose without hindrance by devising the structure including the arrangement of each device.

[0004]

In order to achieve the above-mentioned object, the present invention is to connect an excavation work device to the left and right intermediate portions of the front part of a swivel base, and to provide a control section on one lateral side of the excavation work device. Also, in a backhoe swivel base structure in which hydraulic oil tanks are provided on the other sides, respectively, and a drive unit is provided at the rear of the swivel base, the engine of the drive unit is laid across the left and right sides at the rear of the swivel base. Mounted on a pipe engine frame
A characteristic feature is that a return hose connecting a control valve for an excavation work device arranged in a control section and a hydraulic oil tank is arranged through an internal space of an engine frame.

[0005]

In other words, a pipe material having sufficient strength is used for the mounting frame of the engine, and the return hose is passed through the pipe material so that the engine frame has both functions of a strength member and a hose path. Among the oil passages connecting the control valve and the tank, or the hydraulic pump, the return hose, which is the drain passage for all the oil passages, has the largest diameter. By passing the inner space of the pipe material, which is a dead space,
It is possible to effectively promote the downsizing of the swivel base.

[0006]

Therefore, the return hose, which requires a relatively large amount of installation space, can be laid out in the engine section by a simple modification in which the engine frame is composed of the pipe material extending left and right. A rational structure that can contribute to further downsizing of the swivel base was obtained by making the constituent members multi-functional.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. An ultra-small turning type backhoe is shown in FIG. 4, in which A is an excavation work device, 4 is a swivel platform, 5 is a traveling platform, and 6 is a crawler traveling device. The excavation work apparatus A is configured to include a boom 1, an arm 2 and a bucket 3. The boom 1 can be bent and displaced freely, and the bucket 3 can be in a storage posture in which it is positioned on the right side of the boom 1.

As shown in FIGS. 1, 2, and 4, the swivel base 4
The steering section 7, the connecting section 8 of the boom 1 and the tank section 9 are arranged from the left at the front of the vehicle, and the driving section B extending left and right is arranged at the rear. The tank portion 9 is provided with a hydraulic oil tank 10 and a fuel tank 11 and is covered with a tank cover 12 that can be opened and closed.

The drive part B is covered with an engine hood 13 which can be opened and closed, and includes an engine E, a radiator R, and a first
The third hydraulic pumps P _{1 to} P _{3 and the} like are mounted on the mounting frame 14. The mounting frame 14 includes the left and right substrates 14
a, 14b, front and rear square pipe engine frames 14
c, 14d, and the mounting piece 14e are integrated. Then, the assembly control valve V group for excavating device arranged on the steering unit 7, the hydraulic pump P ₁ to P _3, are pipe by four hydraulic hoses 15-18 and hydraulic oil tank 10. That is, the first and second pumps P ₁ and P ₂ and the first and second pumps
The supply hoses 15 and 16 are for the work control valve V, and the third
The pump P ₃ and the third hose 17 are for the pilot valve v for pilot operation, and are provided with a single return hose 18 that joins the drain passages of the work control valve V and the pilot valve v.

Three hoses 15, 16, 1 for supplying pressure oil
7 are vertically arranged side by side with a clamp 20 on a horizontal partition wall 19 for partitioning the drive part B and the connecting part 8, and are piped in a narrow gap between the engine E and the horizontal partition wall 19. The large-diameter return hose 18 is connected to the front engine frame 14
It is led to the hydraulic oil tank 10 through the inside of c and contributes to compactification by bringing the horizontal partition wall 19 and the engine E as close as possible. An engine ASSY in which the engine E, the radiator R, and the hydraulic pumps P _{1 to} P ₃ are mounted on the engine frame 14 and a control valve ASSY in which the work control valve V group and the pilot valve v group are used as valve blocks are formed in advance. Therefore, the assembling workability in the main line in the assembling process is improved.

[Other Embodiment] The engine frame 14c is
It is composed of a round pipe, a U-shaped cross section, or a channel material with a narrow angle and two sides with a substantially U-shaped cross section, and returns to these closed internal spaces or partially open internal spaces. A structure through which the hose 18 is passed may be used, and these channel members having corners, round pipes, and an enclosed space where piping can be performed are collectively referred to as "pipe engine frame 14c".

It should be noted that although reference numerals are given in the claims for convenience of comparison with the drawings, the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a partially cutaway plan view showing the structure of a swivel base.

FIG. 2 is a perspective view showing an engine mounting structure.

FIG. 3 is a schematic system diagram of a hydraulic circuit.

FIG. 4 is a side view of the backhoe.

[Explanation of symbols]

 4 swivel base 7 control part 10 hydraulic oil tank 14 engine frame 18 return hose A excavation work equipment B prime mover E engine V control valve

Claims (1)

[Claims] 1. An excavation work device (A) is connected to a left and right intermediate portion of a front part of a swivel base (4), and the excavation work device (A) is connected.
A backhoe in which a control section (7) is arranged on one side of the vehicle, a hydraulic oil tank (10) is arranged on the other side, and a driving section (B) is arranged at the rear of the swivel base (4). In the swivel structure, the engine (E) of the driving part (B) is mounted on a pipe engine frame (14) which is installed on the left and right sides of the rear part of the swivel (4), and Division (7)
Valve (V) for the excavation work device (A) arranged in
A backhoe swivel structure in which a return hose (18) for connecting the hydraulic oil tank (10) and the hydraulic oil tank (10) is arranged through the internal space of the engine frame (14).