JP3412577B2 - Hydraulic excavator - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic excavator in which an upper revolving structure is mounted on a lower traveling structure, and each control valve for controlling the operation of each working machine actuator is provided on the bottom plate of the upper revolving structure. It is about.

[0002]

2. Description of the Related Art Generally, a hydraulic excavator has an upper revolving structure mounted on a lower traveling structure (usually a crawler), and an excavation attachment having a boom, an arm and a bucket is mounted in front of the upper revolving structure. By constructing a vehicle body by using an engine mounted on an upper swing body as a drive source and rotating a hydraulic pump, and supplying the discharge oil to a hydraulic actuator (hydraulic motor or hydraulic cylinder) via each control valve, Run, turn, boom up / down, arm operation, bucket operation. Further, there is also one in which a dozer is provided in the rear portion of the lower traveling body, and the discharged oil is supplied to a hydraulic actuator (hydraulic cylinder) via a control valve to operate the dozer.

[0003]

By the way, as for the work environment of shovels in recent years, work in narrow spaces has been increasing mainly in urban civil engineering, and along with this, the demand for small hydraulic excavators has increased. There is. Small hydraulic excavators require a small space for the equipment to be installed, and there are severe restrictions particularly in the length and width directions of the vehicle body. However, it was difficult to further reduce the size of the hydraulic excavator because of the arrangement of the control valves.

That is, since the control valves are connected to each other by pipes, they are often centrally arranged, so that a large installation space is required. Here, if each control valve is placed horizontally, it is possible to keep the installation space in the vertical direction low, but the occupancy rate of each control valve becomes high in the plane of the machine, which does not meet the demand for downsizing. On the other hand, if each control valve is placed vertically, it is possible to reduce the horizontal installation space when laying out each control valve under the floor plate, but a side deck that is higher than the total length of each control valve is required. Therefore, even in this case, the demand for miniaturization is not met.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a hydraulic excavator which is easy to work in a narrow space by further downsizing.

[0006]

Claim 1 of the present invention According to an aspect of the upper rotating body is mounted on the lower traveling body, the upper rotating body
In a hydraulic excavator in which each control valve for controlling the operation of each working machine actuator is provided on the bottom plate under the floor plate, the above-mentioned each by tilting in one of the left and right directions in the space on the bottom plate. It is configured as a hydraulic excavator characterized by arranging control valves in parallel.

According to this structure, the floor swing of the upper swing body is
Since the control valves were installed side by side in one of the left and right directions in the space above the bottom plate under the rate , each control valve is in a smaller space in both the vertical and horizontal directions. However, it will be installed, which will lead to further miniaturization of the car body.

In the hydraulic excavator according to claim 1,
If a holding table for holding the control valves so as to rise and slope toward the reinforcing frame side provided on the bottom plate is provided (claim 2), the control valves are installed so as to overlap the frame. This leads to further miniaturization. Moreover, since the height of the reinforcing frame can be increased, the reinforcing effect of the bottom plate can be enhanced.

Particularly, in the hydraulic excavator according to a second aspect of the present invention, each of the control valves includes a mechanical control valve connected to at least one of an operation lever and an operation pedal by a link mechanism, and the link mechanism includes: When it is arranged so as to pass over the reinforcing frame (claim 3), the link mechanism becomes simple.

In the hydraulic excavator according to claim 2 or 3, if the holding base holds all of the control valves at a constant inclination angle (claim 4),
The structure is simplified.

In the hydraulic excavator according to any one of claims 2 to 4, the holding base has a pipe connecting portion which is connected to at least the working machine actuator among the pipe connecting portions of the control valves. If the control valves are held so that the pipes are directed upward (claim 5), the connection of the pipes is facilitated, and a smaller piping space is required.

For example, each of the working machine actuators includes a swing cylinder, a boom cylinder, an arm cylinder, a bucket cylinder, a swing motor, and a left and right traveling motor.

[0013]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows the overall construction of the hydraulic excavator according to this embodiment. In the figure, 1 is a lower traveling structure of the hydraulic excavator, 2 is an upper revolving structure, 3 is a front attachment mounted on the front part of the upper revolving structure 2, and 4 is a rear attachment mounted on the rear part of the lower traveling structure 1. is there.

The lower traveling body 1 is composed of left and right crawler frames 5 and crawlers 6 each having only one surface,
The two-sided crawlers 6 are individually driven to rotate by the traveling motor 7 to travel. The upper revolving structure 2 is composed of a revolving frame 8, a driver's seat 9, etc., and an engine (not shown) as a power source and a hydraulic pump driven by this engine are provided in a machine room 10 on the revolving frame 8. (Omitted) is installed. In addition, below the front of the driver's seat 9, the operation levers 11, 12 are provided.
Also, the operation pedal 13 is provided on the floor plate 14, and the driver operates the machine by these operations.
The front attachment 3 is a boom 1 which is attached to the revolving frame 8 so as to be swingable and undulating.
5. The arm 16 is rotatably attached to the tip of the boom 15, and the bucket 17 is rotatably attached to the tip of the arm 16. It is available. The rear attachment 4 comprises a dozer 22 rotatably attached to the crawler frame 5.
It is driven by the expansion and contraction of the cylinder 23 so that it can handle various types of work.

FIG. 2 is a plan view showing an arrangement example of equipment under the floor of the hydraulic excavator, and FIG. 3 is a partial elevational view thereof (a view taken along the line AA). As shown in FIGS. 2 and 3, further below the floor plate 14 is a main frame 30 that is a bottom plate of the revolving frame 8, vertical plates 31 and 32 that are reinforcing frames of the main frame 30, and a side that covers the outside of the left and right spaces. It is composed of decks 33 and 34.

Of these, the main frame 30 has a thin plate structure over the entire bottom surface of the revolving frame 8 and is reinforced with ribs at appropriate places. The vertical plates 31 and 32 are the main frame 30.
The main frame 3 is erected on the top at appropriate intervals.
Although it is a thick plate structure that is a strength member of 0, it is set to a predetermined height to ensure its strength. Side deck 3
Reference numerals 3 and 34 each have a thin plate structure that forms the outer skin of the revolving frame 8. However, in order to secure its strength, appropriate places are inflated to the outside. After all, the lower part of the floor plate 14 is divided into the following three spaces (first to third spaces) by these respective members.

First, in the first space 35 surrounded by the floor plate 14, the main frame 30, the vertical plate 31, and the side deck 33, a control valve group, which is a feature of this embodiment, is arranged. That is, 40L, 40 in the figure
R is a left / right travel motor directional control valve that controls the left and right travel motors 7, 41 is a swing directional control valve that controls the swing cylinder 18, and 43 is a service (OP).
It is a direction switching valve of T). Each of these directional control valves is a mechanical type that is connected to at least one of the operation lever 12 and the operation pedal 13 by a link mechanism.
The arrangement has certain restrictions as described later. Also,
Reference numeral 42 in the figure denotes a dozer directional control valve for controlling the dozer cylinder 23, which is of a cable pull type, but the restrictions on its arrangement are almost the same as those of the mechanical type which is connected by the link mechanism. . Further, in the figure, 44 is a boom directional control valve for controlling the boom cylinder 19, 45 is an arm directional control valve for controlling the arm cylinder 20, 46 is a bucket directional control valve for controlling the bucket cylinder 21,
Reference numeral 47 is a directional valve for a swing motor that controls a swing motor (not shown). All of these directional control valves are pilot type controlled by pilot pressure oil discharged from a pilot pump (not shown) driven by an engine (not shown). Compared with this, there are few restrictions on the arrangement and they can be arranged in any order.

Next, in the second space 48 surrounded by the floor plate 14, the main frame 30, the vertical plate 31, and the vertical plate 32, a link mechanism for connecting to the mechanical directional control valve is installed. For example, in the case of the left drive motor directional control valve 40L, the floor plate 14 is inserted through the operation lever 12 and the operation pedal 13 arranged on the floor plate 14, and either of the operation lever 12 and the operation pedal 13 is inserted. A first lever member 49 that transmits the operating direction and force is extended downward, and its tip is connected to a rotating member 50 that extends in the front-rear direction. Further, the rotary member 50 is connected to the second lever member 51, and the tip end thereof is the travel motor direction switching valve 40L on the left.
Is connected to the connection part of. Therefore, when the driver operates either the operation lever 12 or the operation pedal 13, the operation direction and force of the operation lever 1 via the first lever member 49, the rotating member 50 and the second lever member 51 are the directional control valve. It is transmitted to 40L and controls this mechanically. The other mechanical directional control valves 40R, 41, 42, 43 have the same configuration as above.

Further, a third member surrounded by the floor plate 14, the main frame 30, the vertical plate 32 and the side deck 35.
The swing cylinder 18 is installed in the space 52. That is, the swing cylinder 18 has the vertical plate 32.
The rear end of the vertical plate 32 is rotatably supported in a plane substantially parallel to the vertical plate 32. For this reason, the vertical plate 32 becomes closer to the front end from the center, and the vertical plate 32 and the swing plate during the swing operation. The interference with the cylinder 32 is avoided.

By the way, the directional control valves 40L, 40R, 41 to 47 installed in the first space 35 are
All are fixed by bolts or the like on a holding base 53 having a holding surface that forms a slope at a certain angle toward the vertical plate 31, and are connected to the main line 55 by a connecting member 54 for high pressure piping above these valves. It is connected. This holding table 53
Are mounted on ribs that reinforce the main frame 30, and the ribs are further welded to the vertical plate 31, which causes harmful vibrations and the like on each direction switching valve fixed to the holding table 53 even during work. There is no such thing. Holding table 5
The inclination angle of the holding surface of No. 3 is determined so that the vertical plate 31 is as high as possible and the valve installation space including the connection with the main line 55 is as small as possible. Here, in order to make the holder 53 as simple as possible,
Although the inclination angle of the holding surface is constant, it need not always be constant.

The main line 55 is a directional control valve 40.
L, 40R, 41-47 and corresponding cylinders 18-21, 23 which are working machine actuators are connected to each other, and as shown in FIG. 3, bend at right angles near the upper portion of each directional control valve. Piping can be performed even in a narrow space directly below the floor plate 14. The main line connecting the directional control valves 40L, 40R, 41 to 47 to the hydraulic pump (not shown) and the tank (not shown) is a common line of the directional control valves, so that, for example, inside each valve body, This line is formed by partially communicating, and it is not necessary to make a pipe connection for each valve, so it is not shown in the figure. In this case, for the large-diameter line, it suffices to connect the main line 55 at the connection portion above each directional control valve, so that pipe mounting work and maintenance work thereof are facilitated.

Further, mechanical directional control valves 40L, 40R,
Regarding 41 and 43, the link mechanism is connected so as to jump over the vertical plate 31, but in the present embodiment, the link connection portion of the directional control valve is inclined upward, and the vertical plate 31 is moved by that amount. Can only be extended upwards. That is, the vertical plate 31, together with the other vertical plate 32, guarantees strength against bending deformation applied to the front-rear direction of the upper revolving superstructure 2 during various operations. Need to be bigger. However, on the side of the vertical plate 32, only a pipeline with which the swing cylinder 18 can be relatively freely bent can be passed, and the plate height is not limited, whereas on the side of the vertical plate 31, the lever member can be bent. Since it is necessary to pass through a link mechanism that requires a linear layout such as a combination of a rotating member and
Conventionally, it was difficult to obtain the plate height unless the link mechanism had a complicated structure. Therefore, in this embodiment,
By lifting the link connection portion of the mechanical directional control valve and raising the vertical plate 31 over which the link mechanism jumps, the vertical plate 31 with certain restrictions on its layout is first provided with the simple structure of the link mechanism. The bending rigidity could be improved significantly. The same applies to the cable pulling direction switching valve 42. The pilot type directional control valves 44, 45, 46, 47 are not limited to the mechanical type directional control valves described above, but even in this case, the vertical plate 31 is jumped over by inclining the directional control valves. Since the selector or the pilot port portion projecting at the end of the valve can be arranged, there is an advantage in arrangement.

These directional control valves operate as follows. That is, the pressure oil discharged from the hydraulic pump is supplied to the left and right traveling motors 7 and the like via the respective direction switching valves 40L, 40R, 41 to 47, and the respective operations are performed.
Here, the mechanical directional control valves 40L, 40R, 41, 4
The operations of Nos. 2, 43 are mechanically performed as described above, but the pilot type directional control valves 44, 45, 46, 47 are used.
The operation of is controlled by supplying pilot pressure oil discharged from a pilot pump (not shown) to each pilot port according to an operation signal from a remote control valve (not shown) of the operation lever.

According to this structure, the upper side of the main frame 30 of the revolving frame 8 of the upper revolving structure 1 is provided with the vertical plates 31, 3.
2 is divided into three spaces in the left-right direction, and each of the directional control valves 40L is tilted toward the vertical plate 31 side in any one of these spaces, for example, the first space 35 in the above case,
Since 40R and 41 to 47 are arranged side by side, these directional control valves can be arranged even in a smaller space, and can be made smaller in the length direction and width direction of the vehicle body to achieve further miniaturization. This makes it possible to obtain a hydraulic excavator that can be easily operated in a narrow space.

In the above embodiment, both the mechanical type and the pilot type directional control valve are used, but all the pilot type directional control valves may be used. In that case, since there is no constraint imposed by the connection with the link mechanism as in the mechanical directional control valve, the inclination direction of each directional control valve can be reversed left and right. Further, in the above embodiment, the main plate 30 is divided into three spaces in the left-right direction by the vertical plates 31 and 32. However, for example, it is divided into two spaces in the left-right direction and the direction switching valve is inclined to one of the spaces. They may be arranged side by side. Alternatively, a large machine may be divided into more spaces. Further, in the above embodiment, the engine directly drives the hydraulic pump, but the engine may drive the generator and the generated electric power may drive the hydraulic pump. Further, in the above-described embodiment, since the boom 15 is swung, the directional switching valve 41 for swing for driving the swing cylinder 18 for that purpose is provided. However, when such a function is not provided, the directional switching valve 41 is provided. Can be omitted. Of course, the other directional control valves may be increased or decreased as appropriate.

[0027]

As described above, according to the first aspect of the present invention.
Is a hydraulic excavator in which an upper revolving structure is mounted on a lower traveling structure, and each control valve for controlling the operation of each working machine actuator is provided on the bottom plate under the floor plate of the upper revolving structure. In the above space, the control valves are arranged in parallel with each other so as to be inclined in either one of the left and right directions.

According to this construction, the floor swing of the upper swing body is
Since the control valves were installed side by side in one of the left and right directions in the space above the bottom plate under the rate , each control valve is in a smaller space in both the vertical and horizontal directions. However, it can be installed, and the size of the vehicle body can be further reduced. This makes it possible to obtain a hydraulic excavator that can be easily operated in a narrow space.

In the hydraulic excavator according to claim 1,
Since each of the control valves is provided with a holding base that holds the control valve so as to ascend toward the reinforcing frame provided on the bottom plate (claim 2), each control valve can be installed so as to overlap the frame, Further size reduction can be achieved. Moreover, since the height of the reinforcing frame can be increased, the reinforcing effect of the bottom plate can be enhanced.

In particular, in the hydraulic excavator according to the second aspect, each of the control valves includes a mechanical control valve connected to at least one of an operation lever and an operation pedal by a link mechanism, and the link mechanism is When it is arranged so as to pass over the reinforcing frame (claim 3), the link mechanism becomes simple.

In the hydraulic excavator according to claim 2 or 3, if the holding base holds all of the control valves at a constant inclination angle (claim 4),
The structure is simplified.

In the hydraulic excavator according to any one of claims 2 to 4, the holding base has a pipe connecting portion that is connected to at least the working machine actuator among the pipe connecting portions of the control valves. If the control valves are held so that the pipes are directed upward (claim 5), the connection of the pipes is facilitated, and a smaller piping space is required.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an entire hydraulic excavator according to the present embodiment.

FIG. 2 is a plan view showing an arrangement example around a directional control valve.

FIG. 3 is a partial elevational view showing an arrangement example around a directional control valve.

[Explanation of symbols]

1 Lower Revolving Body 2 Upper Revolving Body 3 Front Attachment 4 Rear Attachment 8 Revolving Frame 12 Control Lever 13 Control Pedal 14 Floor Plate 18 Swing Cylinder (Work Machine Actuator) 19 Boom Cylinder (Work Machine Actuator) 20 Arm Cylinder (Work Machine) Actuator) 21 Bucket cylinder (Work machine actuator) 23 Dozer cylinder (Work machine actuator) 30 Main frame (Bottom plate) 31, 32 Vertical plate (Reinforcement frame) 33, 34 Side decks 40L, 40R (Control valve, mechanical control valve) 41 Swing directional control valve (control valve, mechanical control valve) 42 Dozer directional control valve (control valve) 43 Service directional control valve (control) , Mechanical control valve) 44 Boom direction switching valve (control valve) 45 Arm direction switching valve (control valve) 46 Bucket direction switching valve (control valve) 47 Swing motor direction switching valve (control valve) 49 1st Lever member (link mechanism) 50 rotating member (link mechanism) 51 second lever member (link mechanism) 53 holding base 54 connecting member (pipe connecting portion) 55 main line (pipe)

Claims (5)

(57) [Claims] 1. An upper revolving structure is mounted on a lower traveling structure,
In a hydraulic excavator in which each control valve for controlling the operation of each actuator for each work machine is provided on the bottom plate under the floor plate of the upper swing body , in either of the left and right directions within the space on the bottom plate. A hydraulic excavator characterized in that the above-mentioned control valves are installed side by side in a tilted manner. 2. The reinforcing frame is attached to the upper surface of the bottom plate, and a holding base is provided for holding each of the control valves so as to incline upward toward the reinforcing frame. Hydraulic excavator. 3. Each of the control valves includes a mechanical control valve connected to at least one of an operation lever and an operation pedal by a link mechanism, and the link mechanism is arranged so as to pass over the reinforcing frame. The hydraulic excavator according to claim 2, wherein 4. The hydraulic excavator according to claim 2 or 3, wherein the holding table holds all of the control valves at a constant inclination angle. 5. The holding table holds each control valve such that at least a pipe connecting portion connected to each of the working machine actuators, of the pipe connecting portions of each control valve, faces upward. It is a thing, The hydraulic excavator in any one of Claims 2-4 characterized by the above-mentioned.