JP2003154856A - Swing type construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the workability of assembling or the like by positioning a counter weight near an engine which is mounted on a revolving frame with three-point supports, and making easy piping work to a hydraulic pump. SOLUTION: The revolving frame 11 of an upper swing body comprises a base plate 12 formed in a substantially disc-like shape, and a right longitudinal plate 14, left front longitudinal plate 15, transverse plate 17, left rear longitudinal plate 18, and the like built on the base plate 12. On the rear portion of the revolving frame 11, first and second engine mounts 25, 26 are disposed in positions before the engine crankshaft and behind the transverse plate 17, and a third engine mount 27 is disposed in a position behind the engine crankshaft and roughly at a midpoint between the engine mounts 25, 26.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swivel construction machine such as a hydraulic excavator, and more particularly to a swivel construction machine configured to support an engine as a power source at three points on a rear side of a swing frame.

[0002]

2. Description of the Related Art Generally, construction machines such as hydraulic excavators are
An undercarriage, an upper revolving structure rotatably mounted on the lower revolving structure, and a working device provided on the front part of the upper revolving structure so as to be able to move up and down, and operate the working device. By this, excavation work such as earth and sand is performed.

An upper revolving structure of such a hydraulic excavator includes a revolving frame mounted on a lower traveling structure via a revolving wheel, and a cab provided on the front left side of the revolving frame to define a driver's cab. An exterior cover that is located on the rear side of the cab and that is provided inside the revolving frame and that houses an engine, a hydraulic pump, and the like that serve as a power source, and a revolving frame that is located on the rear side of the exterior cover. It is configured by a counterweight that balances the weight of the working device.

The engine, which is the power source of the hydraulic excavator, is generally arranged horizontally on the rear side of the revolving frame. For example, a total of four engines are separated from each other in the front, rear, left and right directions of the engine. It is mounted on the revolving frame in a four-point supported state by using the engine mount (for example, Japanese Patent Laid-Open No. 5-1433).

Further, the counterweight arranged on the rear side of the engine has a rear end side curved in an arc shape so that the counterweight is housed within a circle having a predetermined turning radius, and its front side is formed on the turning frame. By making the rear side as close to the engine as possible, the rear end side of the counterweight is prevented from coming into contact with surrounding obstacles when the upper swing body swings even in a narrow work site.

[0006]

In the prior art described above, the engine, which is the power source of the hydraulic excavator, is supported at four points by four engine mounts located on the rear side of the revolving frame and in front of the counterweight. Because of the configuration, there are the following problems.

That is, since the four engine mounts are arranged on the front side and the rear side of the engine separately from each other on the left side and the right side, respectively, the two engine mounts arranged on the rear side of the engine mount the counterweight. The installation space is limited, and the counterweight cannot always be installed close to the engine on the rear side of the revolving frame.

As a result, in the conventional hydraulic excavator, the counterweight provided on the rear side of the turning frame extends toward the rear of the vehicle, and it is difficult to sufficiently reduce the turning radius of the upper turning body. There is.

On the other hand, if the counterweight is downsized and formed to have a small weight, the entire upper swing structure can be accommodated within a relatively small swing radius. However, in this case, since the weight of the counterweight is insufficient, there is a problem that it is difficult to improve the work performance of the work device.

That is, the work performance of the work device is improved,
If you try to increase the excavation force, etc., when a large load (excavation reaction force) is applied to the front side of the revolving frame from the work equipment during excavation work such as earth and sand, the rear (counterweight) side of the revolving frame floats up. Such problems will occur.

On the other hand, for example, Japanese Patent Laid-Open No. 11-2403.
An industrial vehicle (hereinafter referred to as other conventional technology) disclosed in Japanese Patent Publication No. 40 has a structure in which an engine is mounted on the rear side of the vehicle in a three-point supported state to enhance vibration damping performance of the engine. Has been done.

However, in this case, one of the three engine mounts in total is arranged at a position below the hydraulic pump on one side of the engine. , When performing piping work, etc., connecting multiple hydraulic pipes to the discharge side, etc.
There is a problem that the engine mount located under the hydraulic pump interferes with the workability during vehicle assembly.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to mount the engine on a swing frame in a three-point supported state so that the counterweight can be arranged close to the engine. An object of the present invention is to provide a swing-type construction machine capable of increasing the weight of the counterweight to enhance the weight balance with respect to the working device and improving the workability at the time of assembling.

[0014]

In order to solve the above-mentioned problems, the present invention provides an undercarriage, an upper revolving structure having a revolving frame rotatably mounted on the lower traveling structure, and the upper revolving structure. A working device provided on the front side of the counter frame, a counter weight for balancing the weight of the working device on the rear side of the revolving frame, and a transversely arranged front side of the counter weight. It is applied to a swing-type construction machine in which a crankshaft is provided with an engine as a power source extending in the left and right directions of the upper swing body.

The feature of the configuration adopted by the invention of claim 1 is that the engine is mounted on the rear side of the revolving frame.
Three engine mounts are provided for mounting in a point-supported state. These engine mounts are located in front of the crankshaft of the engine and are separated from each other in the left and right directions by the first and second engine mounts. The third engine mount is located rearward of the crankshaft of the engine.

With this configuration, the front side is spaced from the left and right sides with respect to the crankshaft of the engine.
It is possible to arrange one engine mount and the remaining one engine mount on the rear side. Keep the counterweight close to the engine on the rear side of the swing frame so as to avoid the rear engine mount. Can be installed. Further, these first to third engine mounts can be arranged at positions apart from the hydraulic pump driven by the engine, and piping work and the like can be easily performed.

Further, according to the invention of claim 2, the third engine mount is arranged at a position between the first engine mount and the second engine mount in the left and right directions of the revolving frame. It is configured.

As a result, the third engine mount can be arranged at a position approximately in the middle in the left and right directions of the engine,
By simply avoiding the third engine mount located on the rear side of the engine, a large installation space for the counterweight can be secured on the rear side of the revolving frame.

According to a third aspect of the invention, a hydraulic pump rotatably driven by a crankshaft is provided on one side of the engine, and the first and second engine mounts are arranged at positions on the front side of the hydraulic pump. It is configured to be installed.

Thus, the first and second engine mounts can be arranged at positions on the front side of the hydraulic pump which is rotationally driven by the crankshaft of the engine. For example, piping work for the hydraulic pump can be performed for each engine. It can be done with plenty of time without being disturbed by the mount.

Further, according to the invention of claim 4, on the front side of the counterweight, there is a recessed portion which is located at an intermediate portion in the left and right directions and is recessed rearward away from the engine, and the recessed portion is sandwiched therebetween. A plurality of build-up portions located on both the left and right sides and projecting toward the engine are provided, and the third engine mount is provided so as to be located in the concave portion of the counterweight.

In this case, the counterweight is brought closer to the engine by disposing the third engine mount in the recessed portion provided on the front side at the intermediate portion of the counterweight in the left and right directions. Can be installed.
Further, padding portions provided on the left and right sides of the concave portion and provided on the front side of the counterweight are provided on the left and right sides of the third engine mount, respectively, on the engine side (for example, a flywheel of the engine). The weight of the counterweight can be increased by largely projecting toward the housing, the hydraulic pump side, etc.).

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION A small swing hydraulic excavator will be described as an example of a swing type construction machine according to an embodiment of the present invention in detail with reference to FIGS. 1 to 5.

In the figure, 1 is a lower traveling body, and the lower traveling body 1 is provided with left and right crawler belts 1A and 1A as shown in FIG. The undercarriage 1 drives the vehicle (hydraulic excavator) forward and backward by driving the crawler belt 1A with a traveling hydraulic motor (not shown) or the like.

Reference numeral 2 denotes an upper revolving structure mounted on the lower traveling structure 1 so as to be revolvable. The upper revolving structure 2 has a revolving frame 11 which will be described later, and a cab 3 serving as a driver's cab is provided on the revolving frame 11. An exterior cover 4, a hydraulic oil tank, a fuel tank (not shown), a counterweight 33 described later, and the like are provided. The exterior cover 4 is located between the cab 3 and the counterweight 33, and the engine 2 described later
8. A machine room that houses the hydraulic pump 30 and the like is defined.

Reference numeral 5 denotes a working device provided on the front side of the upper swing body 2. The working device 5 includes a boom 6 as shown in FIG.
It is composed of an arm 7, a bucket 8 and the like, and the bucket 8 is used for excavating work such as earth and sand.

Reference numeral 11 denotes a revolving frame which constitutes a frame of the upper revolving structure 2. The revolving frame 11 includes a bottom plate 12, vertical plates 14, 15, 18 and a horizontal plate 17 which will be described later as shown in FIGS. It is composed by.

Reference numeral 12 is a bottom plate which serves as a base plate of the revolving frame 11. The bottom plate 12 is formed of a thick steel plate or the like as shown in FIGS. The bottom plate 12 has an imaginary circle 13 with a predetermined turning radius R with respect to the turning center O.
To the front, to the back and to the left and to the right, to the left,
Both right ends are cut along the virtual circle 13 so as to form an arc shape.

Reference numerals 14 and 15 are left and right vertical plates which constitute the revolving frame 11 together with the bottom plate 12, and these vertical plates 14, 1
5 is erected on the upper surface side of the bottom plate 12 using welding means,
The right vertical plate 14 (hereinafter referred to as the right vertical plate 14) is the bottom plate 1
A center line O1-
It extends in the front and back directions parallel to O1.

The left vertical plate 15 (hereinafter, left front vertical plate 1
5) is substantially parallel to the right vertical plate 14 and extends front and rear, but its length dimension is shorter than that of the right vertical plate 14 and its rear end side is welded to an intermediate portion of a horizontal plate 17 described later. Are joined by.

The right vertical plate 14 and the left front vertical plate 15 are
As shown in FIG. 4, it is arranged at a position offset to the right with respect to the center line O1 -O1 passing through the turning center O, and its longitudinal middle portion is pin-coupled so that the boom 6 of the working device 5 can be lowered and raised. The mounting brackets 14A and 15A are used for this purpose. Also, these mounting brackets 14A, 15A
In between, a reinforcing plate 16 is welded to increase the bending strength of the mounting brackets 14A and 15A.

Reference numeral 17 denotes a horizontal plate 17 which is erected on the upper surface side of the bottom plate 12 using welding means and extends to the left and right (width direction) of the bottom plate 12. The horizontal plate 17 has one end (right side). The end portion) is joined to the middle portion in the lengthwise direction of the right vertical plate 14, and the other end portion (the left end portion) extends to the vicinity of the left end portion of the bottom plate 12.

A rear end of the left front vertical plate 15 and a front end of a left rear vertical plate 18, which will be described later, are joined to an intermediate portion of the horizontal plate 17 at positions separated from each other in the left and right directions. And
The horizontal plate 17 connects the left front vertical plate 15 and the left rear vertical plate 18 to the right vertical plate 14 in the left and right directions to increase the bonding strength of the vertical plates 14, 15, 18 to the bottom plate 12. It is a thing.

Reference numeral 18 is a left rear vertical plate as another vertical plate which is erected on the upper surface side of the bottom plate 12 by using welding means. The left rear vertical plate 18 is a horizontal plate 17 with respect to the left front vertical plate 15. The left end and the right end (width direction) are separated from each other at the position, and the front end thereof is welded to the lateral plate 17. The left rear vertical plate 18 extends from the intermediate position in the lengthwise direction of the horizontal plate 17 to the rear end side of the bottom plate 12 substantially in parallel with the right vertical plate 14.

In this case, the distance between the left rear vertical plate 18 and the right vertical plate 14 (distance between the left and right directions) is set to be larger than the distance between the left front vertical plate 15 and the right vertical plate 14. There is. The rear side of the right vertical plate 14 and the left rear vertical plate 18 are the bottom plate 1
The bending strength and the like on the rear side of the second plate 2 are increased to secure a space for installing an engine 28, a counterweight 33, etc., which will be described later, on the rear side of the bottom plate 12.

Reference numerals 19 and 20 denote support beams which are located on the right side of the right vertical plate 14 and are provided on the bottom plate 12.
9 and 20 are separated from each other in the front and rear directions, the base end side is joined to the side surface of the right vertical plate 14, and the tip end side extends rightward along the upper surface of the bottom plate 12. The support beams 19 and 20 support the hydraulic oil tank, the fuel tank, and the like from below in the exterior cover 4 shown in FIG.

Reference numerals 21, 22, 23, and 24 denote four cab mounts provided on the bottom plate 12.
Reference numerals 1 to 24 are made of vibration-proof mount rubber or the like, and support the cab 3 shown in FIGS. 1 and 2 from the lower side at four points.

In this case, the cab 3 is installed by offsetting the vertical plates 14 and 15 from the turning center O on the front left side of the turning frame 11 provided with the cab mounts 21 to 24, as described above. A mounting space is secured, and the cab 3 can be designed to have a wide living space by increasing the width.

Reference numerals 25, 26, and 27 denote first, second, and third engine mounts provided on the rear side of the revolving frame 11, and the engine mounts 25 to 27 are made of vibration isolating mount rubber or the like. The engine 28, which will be described later, is supported on the rear side of the bottom plate 12 at three points from below.

Here, the first and second engine mounts 25 and 26 of the engine mounts 25 to 27 are mounted on a crankshaft 28A (axis C--C) of an engine 28, which will be described later, as shown in FIGS. Is also disposed on the front side and on the rear side of the horizontal plate 17, and is fixed to the upper surface side of the bottom plate 12 using welding means or the like at positions spaced apart from each other in the left and right directions along the horizontal plate 17. There is.

Then, the first engine mount 25 is
It is arranged on the left side of the left rear vertical plate 18 at a position on the front side of a hydraulic pump 30 described later, and the front left side of the engine 28 (the front side of a flywheel housing 29 described later) is placed in a vibration-proof state from the lower side. It is configured to support.

The second engine mount 26 has a center line O on the left side of the right vertical plate 14 and passing through the turning center O.
It is located on the right side of 1-O1. The upper end of the second engine mount 26 is bent obliquely to the front side and extends to support the front right side of the engine 28 from the lower side in a vibration-proof manner.

Further, as shown in FIG. 5, the third engine mount 27 is located behind the axis C-C of the engine 28 and a virtual line AA passing through the engine mount 25 and a virtual line passing through the engine mount 26. It is arranged at a position between the line BB and, preferably, at a substantially intermediate position between the two, and the lower end side thereof is fixed to the rear upper surface side of the bottom plate 12 using welding means or the like. And, the third engine mount 27 is
The upper end side is bent and extends obliquely rearward to support the center of the rear portion of the engine 28 from the lower side in a vibration-proof manner.

In this case, a virtual line AA passing through the engine mount 25 and a virtual line BB passing through the engine mount 26
Extend in a direction substantially orthogonal to the axis C-C of the engine 28 and in a direction substantially parallel to the center lines O1 -O1 and are separated from each other in the directions of the axes C-C (left, right).

Reference numeral 28 denotes an engine as a power source which is mounted on the rear side of the revolving frame 11 by using the engine mounts 25 to 27. The engine 28 is arranged horizontally in the exterior cover 4 shown in FIG. , The bottom plate 1 as shown in FIG.
It is supported at three points on the rear side of the engine 2 through engine mounts 25 to 27.

That is, the engine 28 is fixed to the engine mounts 25 to 27 by using a plurality of bolts (not shown) or the like. The crankshaft 28A of the engine 28 extends to the left and right of the revolving frame 11 along the axis C-C, and a flywheel (not shown) is provided on one end side thereof.

Here, the flywheel housing 2 made of a rigid material such as casting is provided on one side (left side) of the engine 28.
9 is provided, and the flywheel is rotatably accommodated in the flywheel housing 29. Further, a hydraulic pump 30 is provided on one side of the engine 28 via a flywheel housing 29, and the hydraulic pump 30 is rotationally driven by a crankshaft 28A of the engine 28, so that the hydraulic oil in the hydraulic oil tank is Is discharged as pressure oil.

The engine 28 has a crankshaft 28A.
The cooling fan 31 is provided on the other side of the cooling fan 31.
Is rotatively driven by the engine 28, so that cooling air is circulated around the engine 28 from the radiator 32 side toward the hydraulic pump 30 side. And
The radiator 32 is arranged on the bottom plate 12 at a position facing the cooling fan 31, and cools the cooling water of the engine 28 and the like by the cooling air.

Reference numeral 33 is a counterweight that is detachably attached to the rear end side of the revolving frame 11, and the counterweight 33 is located on the rear side of the engine 28 and is located in the working device 5.
The weight balance is imparted to the revolving frame 11 between and. Then, the rear surface side of the counterweight 33 extends in an arc shape along a virtual circle 13 having a turning radius R as shown in FIGS. 2 and 4, and when the upper turning body 2 turns, the counterweight 33 obstructs surroundings. It is configured to prevent collision with an object or the like.

On the front surface side of the counterweight 33, a padding portion 33 for increasing the weight of the counterweight 33 as much as possible.
A, 33B, 33C and 33D are provided separately on the left and right. Also, on the front side of the counterweight 33,
A concave portion 33E, which is curved in an arc shape, is formed between the built-up portions 33C and 33D at an intermediate portion in the left and right directions to avoid contact and interference with the engine mount 27.

Of the built-up portions 33A to 33D of the counterweight 33, the built-up portions 33A and 33C on the left side are provided.
Is formed so as to largely project to the front side to a position close to the flywheel housing 29 and the hydraulic pump 30, as shown in FIG. Also, the padding portion 33B on the right side,
33D is formed so as to project to the front side so as to partially cover the radiator 32 described below from the rear side and the right side.

The small turning hydraulic excavator according to the present embodiment has the above-mentioned structure, and its operation will be described below.

First, when the hydraulic pump 30 is driven by the engine 28 housed in the exterior cover 4, the hydraulic pump 3
The pressure oil from 0 is supplied to and discharged from the traveling motor (not shown) of the lower traveling body 1 to drive the crawler belt 1A shown in FIG. 1 to move the hydraulic excavator (vehicle) forward or backward.

When excavating earth and sand, etc.,
By rotating the bucket 8 while raising and lowering the boom 6 and the arm 7 of the work device 5, the bucket 8 is used to excavate earth and sand or the like. And the working device 5
Since a large load is applied to the front side of the swivel frame 11 when excavating earth and sand by the swivel frame 11
May be subject to external forces that lift the rear side.

Therefore, a counterweight 33, which is a heavy load, is provided on the rear side of the revolving frame 11, and the working device 5 is used.
The counter weight 33 is used to balance the weight of the counter weight. Further, the engine 28 housed in the exterior cover 4 is also arranged on the rear side of the revolving frame 11 as close as possible to the counterweight 33, and is configured to balance the weight with the counterweight 33.

In order to realize a small turning within the vehicle width, the upper swing body 2 has a lateral width (2 × R) of the upper swing body 2 which is twice the turning radius R shown in FIG. Car width W
(Dimension between the left and right crawler belts 1A) The dimensions are set as follows, and the entire upper revolving structure 2 is housed within a virtual circle 13 having a revolving radius R as small as possible.

Thus, in the present embodiment, the engine 28 is provided between the cab 3 and the counterweight 33 on the revolving frame 11, and the first to third engine mounts 25 are provided.
.About.27 are used to support three points in a horizontal position.

The engine mounts 25-
Of 27, first and second engine mounts 25, 26
Is a front side of the crankshaft 28A (axis C-C) of the engine 28 and the lateral plate 17 as shown in FIGS.
It is arranged at a position on the rear side of the vehicle, spaced apart in the left and right directions.

As shown in FIG. 5, the third engine mount 27 is located on the rear side of the axis C-C of the engine 28 and on an imaginary line A- passing through the engine mounts 25 and 26.
It is arranged at a position approximately midway between A and the virtual line BB (a position approximately midway between the engine mounts 25 and 26).

As a result, these engine mounts 2
5, 26, 27 can be arranged at three points forming the corners of the isosceles triangle, and the engine 2 can be installed at the rear side of the revolving frame 11.
8 can be stably supported at three points by the engine mounts 25 to 27.

Then, the first engine mount 25 is
Since it is arranged on the left side of the left rear vertical plate 18 on the front side of the hydraulic pump 30, and the flywheel housing 29 of the engine 28 is supported from the lower front side,
For example, when connecting hydraulic piping to the hydraulic pump 30,
The piping work for the hydraulic pump 30 can be easily performed without paying special attention to the engine mount 25 (26, 27) and the burden on the operator can be reduced.

Further, the third engine mount 27 can be arranged at a position close to the center line O1-O1 passing through the turning center O, and the concave portion 33 is formed in the center portion on the front surface side of the counterweight 33.
By forming E, it is possible to easily avoid contact and interference between the counterweight 33 and the engine mount 27, whereby the front side of the counterweight 33 is brought as close as possible to the engine 28, and the rear end of the revolving frame 11 is moved. A counterweight 33 can be installed on the side.

On the front side of the counterweight 33, the engine 2 is located on the left and right sides of the concave portion 33E.
8, the hydraulic pump 30, the built-up portions 33C, 33D and the like that project toward the radiator 32 side can be formed, and the weight of the counterweight 33 can be reliably increased by these built-up portions 33C, 33D.

Therefore, according to the present embodiment, by mounting the engine 28 on the revolving frame 11 in a three-point supported state, the front side of the counterweight 33 has large built-up portions 33A on both the left and right sides. In addition to 33B, the concave portion 3
The padding portions 33C and 33D can be additionally formed on both sides of 3E.

Then, of the built-up portions 33A to 33D provided on the front side of the counterweight 33, the built-up portion 3 on the left side is formed.
3A, 33C can be formed by projecting to the front side to a position close to the flywheel housing 29 and the hydraulic pump 30, and the right built-up portions 33B, 33D can be formed.
Can be made large in proximity to the radiator 32 and the like.

As a result, the rear surface side of the counterweight 33 can be formed so as to extend in an arc shape along the virtual circle 13 having the turning radius R, without impairing the function of reducing the turning radius R of the upper turning body 2. The weight of the counterweight 33 can be reliably increased by the front surface built-up portions 33A to 33D.

As a result, even when a large load is applied to the front side of the upper swing body 2 by the working device 5, the weight balance with respect to the working device 5 can be enhanced by the counterweight 33 on the rear side, and it is possible to perform the excavation work or the like. It is possible to maintain good vehicle stability and reliably improve work performance and reliability.

Further, the first to third engine mounts 25
27 to 27 can be arranged at positions separated from the hydraulic pump 30, the engine mount 25 can be used when connecting a plurality of hydraulic pipes to the suction side and the discharge side of the hydraulic pump 30, respectively.
It is possible to satisfactorily perform the piping work without being disturbed by ~ 27 and improve the workability when assembling the hydraulic excavator (vehicle).

In the above embodiment, the virtual line A passing through the third engine mount 27 and the engine mount 25 is used.
-A and the virtual line BB passing through the engine mount 26 have been described as an example in the case of being arranged at an approximately intermediate position, but the present invention is not limited to this and, for example, a modification shown in FIG. In addition, the third engine mount 27 ′ may be arranged on the imaginary line BB passing through the engine mount 26 on the rear side of the axis C-C of the engine 28.

Further, as indicated by a virtual line in FIG.
The engine mount 27 ″ of the engine 28 axis C-C
A virtual line A-A passing through the engine mount 25 on the rear side of
It may be arranged above.

In the above embodiment, the upper swing body 2
Cab 3, exterior cover 4 and counterweight 33
The above description has been given by taking a small turning hydraulic excavator having a configuration in which the above are housed in the virtual circle 13 having the turning radius R as an example, but the present invention is not limited to this, and even for a medium hydraulic excavator, for example, By using a three-point support structure for the engine on the revolving frame, it is possible to prevent the installation space of the engine from increasing and it is possible to design the layout inside the exterior cover with a high degree of freedom. is there.

Further, in the above-described embodiment, the engine 28 is placed horizontally on the revolving frame 11, and the cab 3
The flywheel housing 29 and the hydraulic pump 30 are provided on one side (left side) of the engine 28 which is the rear side of the engine 28, and the cooling fan 31 and the radiator 3 are provided on the other side (right side) of the engine 28.
Although the hydraulic excavator configured to provide two is described as an example, the present invention is not limited to this, and for example, a cooling fan, a radiator, etc. are provided on one side (left side) of the engine, which is the rear side of the cab, and the other side is provided. A configuration may be provided in which a flywheel housing, a hydraulic pump, and the like are provided (on the right side).

Further, it may be applied to a construction machine such as a hydraulic excavator having a structure in which, for example, a canopy for covering the driver's seat from the upper side is provided instead of the cab 3 defining the cab. The working device 5 may be a so-called offset boom type front device or a swing post type working device.

Further, although the hydraulic excavator has been described as an example in the above-mentioned embodiment, the present invention is not limited to this, and may be applied to, for example, a dredger or the like in which an upper swing body or the like is mounted on the hull. Well, or may be applied to a swing type construction machine having an upper swing body such as a self-propelled crane.

[0075]

As described above in detail, according to the invention of claim 1, since the engine is mounted on the rear side of the revolving frame in a three-point supported state, the engine is positioned in front of the crankshaft of the engine. First and second separated from each other in the left and right directions
Since the engine mount and the third engine mount located on the rear side of the crankshaft of the engine are provided, the two engine engines are spaced apart left and right on the front side with respect to the crankshaft of the engine. Place the mount,
The remaining one engine mount can be arranged on the rear side, and the counterweight can be installed close to the engine on the rear side of the revolving frame so as to avoid the engine mount on the rear side. Further, a large amount of padding can be applied to the front surface side of the counterweight, so that the weight of the counterweight can be increased, and the weight balance with respect to the working device can be increased to improve work performance and the like. Also,
The first to third engine mounts can be arranged at positions apart from the hydraulic pump driven by the engine, and piping work and the like can be performed easily, and workability during vehicle assembly can be improved.

According to the second aspect of the invention, the third engine mount is arranged at a position between the first engine mount and the second engine mount in the left and right directions of the turning frame. Because of the configuration, the third engine mount can be arranged at a position approximately in the middle in the longitudinal direction of the engine, and a counterweight installation space can be provided on the rear side of the revolving frame simply by avoiding the third engine mount. It can be secured large.

According to the third aspect of the invention, a hydraulic pump rotatably driven by a crankshaft is provided on one side of the engine, and the first and second engine mounts are located in front of the hydraulic pump. Since it is configured to be installed in
The first and second engine mounts can be arranged at positions on the front side of the hydraulic pump that is rotationally driven by the crankshaft of the engine. For example, for piping work on the hydraulic pump,
It can be done with plenty of time without being disturbed by each engine mount.

Further, in the invention as set forth in claim 4, the counterweight is provided on the front side thereof with a recessed portion located at an intermediate portion in the left and right directions and a plurality of recessed portions located on both the left and right sides of the recessed portion. Since the padding portion is provided and the third engine mount is provided so as to be located in the concave portion of the counterweight, the third engine mount can be arranged in the concave portion of the counterweight. The counterweight can be installed close to the engine. In addition, the padding portion provided on the front side of the counterweight is provided on the left and right sides of the third engine mount on the flywheel housing of the engine,
The weight of the counterweight can be reliably increased by forming it so as to largely project toward the hydraulic pump and the radiator side. Therefore, even when the turning radius of the upper-part turning body is reduced and the counterweight is downsized, the counterweight can be arranged within the range of the predetermined turning radius to increase the weight, and the weight can be increased. It is possible to improve the weight balance of the counterweight and improve the work performance of the construction machine.

[Brief description of drawings]

FIG. 1 is a front view showing a hydraulic excavator according to an embodiment of the present invention.

FIG. 2 is a plan view of the hydraulic excavator shown in FIG.

FIG. 3 is an enlarged perspective view showing the swivel frame of FIG.

FIG. 4 is an enlarged plan view showing a swivel frame in FIG. 1.

5 is an enlarged view of an essential part of FIG. 4, showing a state in which an engine and a counterweight are attached to a rear side of a swing frame.

FIG. 6 is a plan view similar to FIG. 4, showing a swing frame provided with an engine mount according to a modification.

[Explanation of symbols]

1 Undercarriage 2 Upper revolving structure 3 cabs 4 Exterior cover 5 Working device 11 swivel frame 12 Bottom plate 13 virtual circles 14 Right vertical plate 15 Left front vertical plate 17 Horizontal plate 18 Left rear vertical plate 21-24 cab mount 25 First engine mount 26 Second engine mount 27,27 ', 27 "Third engine mount 28 engine 28A crankshaft 29 flywheel housing 30 hydraulic pump 31 cooling fan 32 radiator 33 counterweight 33A-33D Meat buildup part 33E concave part O turning center R turning radius

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazunori Yamada             1-2, Sasagaoka, Mizuguchi Town, Koga District, Shiga Prefecture             Hitachi Construction Machinery Tierra Shiga Factory (72) Inventor Makoto Makoto             1-2, Sasagaoka, Mizuguchi Town, Koga District, Shiga Prefecture             Hitachi Construction Machinery Tierra Shiga Factory (72) Inventor Naohiro Ishikawa             1-2, Sasagaoka, Mizuguchi Town, Koga District, Shiga Prefecture             Hitachi Construction Machinery Tierra Shiga Factory F-term (reference) 2D015 CA00 FA01                 3D035 CA01 CA14 CA19

Claims (4)

[Claims] 1. A revolving frame comprising: a lower traveling body; an upper revolving body having a revolving frame rotatably mounted on the lower traveling body; and a working device provided on a front side of the upper revolving body. On the rear side, a counterweight for balancing the weight with respect to the working device, and a power source arranged in a horizontal position in front of the counterweight and having a crankshaft extending leftward and rightward of the upper revolving superstructure. In the swing-type construction machine provided with the engine as described above, three engine mounts are provided on the rear side of the swing frame for mounting the engine in a three-point supporting state,
These engine mounts are first and second engine mounts located on the front side of the crankshaft of the engine and separated from each other in the left and right directions, and a third engine mount located on the rear side of the crankshaft of the engine. A swing-type construction machine characterized by being configured with an engine mount. 2. The third engine mount is arranged at a position between the first engine mount and the second engine mount in the left and right directions of the revolving frame. Revolving construction machine. 3. A hydraulic pump rotatably driven by a crankshaft is provided on one side of the engine, and the first and second hydraulic pumps are provided.
The swivel construction machine according to claim 1 or 2, wherein the engine mount is arranged at a position on the front side of the hydraulic pump. 4. The front side of the counterweight,
Recessed recesses located in the middle part in the left and right directions and recessed to the rear side away from the engine, and a plurality of build-up parts located on both left and right sides of the recessed part and projecting toward the engine The swivel construction machine according to claim 1, wherein the third engine mount is provided so as to be located inside the concave portion of the counterweight.