JP2002088808A - Rear end small revolving type hydraulic shovel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize the rear end revolving radius without specially sacrificing the space for arranging equipment set on a revolving frame. SOLUTION: In the revolving frame 30, a counter weight 31 forming the rear end revolving radius R is arranged in a former position, and an engine room 32 is arranged forward up to the position where it overlaps the position of a rotating wheel 33 provided in the lower position thereof. Of a swing device formed of the rotating wheel 33 and a revolving drive unit 35, the revolving drive unit 35 is arranged in a position within the rotating wheel 33, which is on the right of the revolving frame 30 and obliquely backward from the rotating center C, so that it interferes with a second frame vertical plate 42b. An opening part 43 for partially passing the housing of the revolving drive unit 35 is formed in the second frame vertical plate 42b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small-end hydraulic excavator in which the distance from the center of rotation of an upper revolving structure to a counterweight disposed at the rear end is reduced to reduce the turning radius of the rear end. Things.

[0002]

2. Description of the Related Art FIG. 6 shows an appearance of a conventional hydraulic excavator, and FIG. 7 shows a revolving frame of an upper revolving body. Generally, a hydraulic excavator is a track-type undercarriage 1
The main body of the vehicle is formed by installing the upper revolving superstructure 3 via the revolving device 2.

A revolving frame 4 of an upper revolving body 3 constituting the vehicle is equipped with a front working machine 5 as working means. The front working machine 5 includes a boom 6 connected to the revolving frame 4 so as to be capable of raising and lowering.
The arm 7 is connected to a tip of the arm 7 so as to be rotatable in the vertical direction, and a front attachment including a bucket 9 and the like that articulate via a link mechanism 8 at the tip of the arm 7.

[0004] An operator cab (cab) 10 is mounted on the revolving frame 4 adjacent to the position where the front working machine 5 is disposed, on which an operator rides and operates the hydraulic excavator. As is clear from FIG. 7, the operator's cab 10 is installed on anti-vibration support devices 11 provided at four locations on the turning frame 4. Most parts other than the positions where the front working machine 5 and the driver's cab 10 are arranged constitute a building 12 surrounded by a cover. A counterweight 13 is provided at the rear of the building 12.

FIG. 7 shows the internal structure of the building 12. In addition,
In FIG. 7, devices and the like installed in the building 12 are omitted, and the arrangement space of these devices and the like is indicated by reference numerals. In the following description,
The direction indicated by arrow F in FIG. The revolving frame 4 is provided with a pair of frame vertical plates 4a and 4b so as to penetrate in the front-rear direction. The base end of the boom 6 of the front working machine 5 described above is connected to the front side of 4b. Further, the rear ends of the frame vertical plates 4a, 4b extend rearward from the revolving frame 4 to support the counterweight 13.

The rear position of the revolving frame 4, that is, the space on the counterweight 13 side is the engine room 1
4, the engine is installed in the engine room 14. For this purpose, four support portions 15 are provided in the engine room 14, and the engine is installed on the support portions 15, and is located substantially at the center of the engine room 14. The engine is provided with a hydraulic pump connected thereto.
A heat exchanger including a radiator is disposed at a left position of the engine room 14, and a left side of the heat exchanger is a space for storing a battery. ing.

[0007] The front position of the engine room 14 in the building 12 is divided into left and right by frame vertical plates 4a and 4b, and the cab 10 is provided on the left side. A tool space, a grease, and the like are stored behind the driver's cab 10 at a position in front of the engine room 14 as a utility space 16.

[0008] On the right side of the frame vertical plate 4b, a space 17 close to the engine room 14 and from which a hydraulic oil tank is arranged.
And its front position is the fuel tank arrangement space 1
8 Further, a front position of the fuel tank arrangement space 18 is a C / V arrangement space 19 in which devices such as a control valve (C / V) are arranged. further,
At the front of the C / V arrangement space 19, a step 20 is mounted.

In the space between the frame vertical plates 4a and 4b, a turning drive unit 21 constituting the turning device 2 is arranged at the rear position, except that an engine room 14 is provided so as to cross. Here, the turning device 2
As is well known, has a turning wheel 22 composed of an outer ring provided on the lower surface of the turning frame 4 and an inner ring provided so as to protrude from the running frame side of the lower running body 1. The outer ring and the inner ring that are configured are fitted so as to be relatively rotatable, and a ring gear is provided on the inner surface of the inner ring. The turning drive unit 21 includes a pinion that meshes with a ring gear provided on the inner ring of the turning wheel 22 and a hydraulic motor that rotates the pinion. Further, peripheral devices such as a relief valve are integrally provided in the housing. It is a thing. The center position c of the turning wheel 22 constituting the turning device 2 configured as described above is the turning center of the upper turning body 3,
A through hole 2 for mounting a center joint for supplying and discharging the hydraulic pressure between the turning center c and the lower traveling body side.
3 are provided.

The housing of the turning drive unit 21 is fixedly provided on the turning frame 4 by a predetermined number of bolts 24.
By attaching and detaching, it is possible to remove it from the turning frame 4. Thus, maintenance such as inspection and repair of the turning drive unit 21 and the like can be performed. The turning drive unit 21 is connected to the turning frame 4
In order to allow easy attachment and detachment with respect to the frame, it is arranged at a substantially intermediate position between the frame vertical plates 4a and 4b. Also,
Since the turning drive unit 21 is a heavy object, the turning drive unit 21 is disposed rearward of the turning center c in order to balance the entire vehicle. Further, in order to easily attach and detach the turning drive unit 21 to and from the turning frame 4, no special members are arranged at positions before and after the place where the turning drive unit 21 is installed. . Therefore, the engine room 14 is disposed at a position separated from the installation portion of the turning drive unit 21 by the distance d.

[0011]

The upper swing body 3 is capable of swinging with respect to the lower traveling body 1, but the swing operation of the upper swing body 3 is appropriately performed even when performing work such as excavation of earth and sand. You. For example, earth and sand are excavated by the front working machine, the excavated soil is stored in the bucket 9, the bucket 9 is set in a posture of being lifted, and the upper revolving unit 3 is swiveled by a predetermined angle, so that the bucket 9 is loaded on the dump truck bed. And the excavated soil is dropped from the bucket 9 to the dump truck. Also, when changing the excavation work position, the upper swing body 3 may be swung to a desired angle, for example, about 180 °.

In urban civil engineering and the like, a work area in which a hydraulic excavator operates may be a narrow place where obstacles such as buildings and trees exist around the work area. Even in such a narrow place, it is necessary to make the turning radius of the upper turning body 3 as small as possible in order to ensure the smoothness of the operation by the hydraulic excavator. If the front work machine 5 raises the boom 6 and folds the arm 7 toward the boom 6, the front work machine 5 can have a relatively compact posture. On the other hand, the turning radius on the rear side does not change. In other words, the counterweight 13 is provided at the rear end of the upper revolving unit 3, and the rear end turning radius extends to the rear end surface of the counterweight 13. For this purpose, the rear end face of the counterweight 13 is an arc surface having a radius r from the turning center c of the turning frame 4 as shown in FIG. Therefore, the rear end turning radius is the radius r.

As described above, the length of the rear end turning radius r,
Depending on the relationship with an obstacle or the like existing at the place where the hydraulic shovel works, there is a case where the work with the hydraulic shovel becomes substantially impossible. Also, even if work can be performed, the excavator cannot be placed in the position where the work can be performed most efficiently in order to avoid contact with obstacles located around, and the turning operation must be carefully performed. Due to the necessity of performing such operations, there are problems such as a decrease in work efficiency such as excavation of earth and sand by a hydraulic shovel.

The present invention has been made in view of the above points, and a purpose thereof is to provide a rear space without particularly sacrificing a space for arranging devices and the like installed on a revolving frame. The object is to reduce the end turning radius.

[0015]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a traveling vehicle in which an upper revolving unit is installed on a lower traveling unit via a revolving device so as to be revolvable. A pair of left and right frame vertical plates is provided on the turning frame to be mounted, a front work machine is mounted at a position in front of both frame vertical plates, and a driver's cab is installed adjacent to the front work machine. A rear excavator having a counterweight connected to the rear ends of the frame vertical plates and having a rear end surface having a substantially circular arc shape centered on the center of rotation of the upper revolving unit; The device is provided with a turning wheel comprising an inner wheel and an outer wheel provided on the traveling frame and the turning frame of the undercarriage, respectively, and installed on the turning frame. A pinion ring gear meshes provided on the inner ring provided on the traveling body frame side, there is constructed from a turning drive unit and a motor for rotating the pinion, of the pair of frame vertical plates,
When the frame vertical plate on the side facing the driver's cab is a first frame vertical plate, and when the frame vertical plate located on the opposite side to the driver's cab is a second frame vertical plate, the turning drive unit includes: Arranged on the side of the arrangement portion of the second frame vertical plate from the center line between the frame vertical plates equally dividing the interval between the first and second frame vertical plates, and behind the center of rotation of the revolving frame. It is characterized by having a configuration of

The turning room is provided with an engine room for accommodating the engine and the like. To reduce the turning radius at the rear end, the engine room may be arranged in front of the turning frame. Thereby, the counterweight constituting the rear end turning radius can be brought closer to the turning center. However, if the engine room is arranged at a position overlapping with the turning wheel, the position of the turning drive unit must be changed. Since the operator's cab is located at the front position of the turning frame, the turning drive unit cannot be displaced in this direction. Therefore, although the turning drive unit is arranged at a position displaced toward the second frame vertical plate, preferably, the turning drive unit is arranged at a position overlapping with the second frame vertical plate. For this purpose, an opening can be formed in the second frame vertical plate, and the turning drive unit can be arranged so as to cross the second frame vertical plate via this opening. Thereby, the engine room and the counterweight can be arranged further forward, and the rear end turning radius can be further reduced.

The frame vertical plate is provided with a front working machine at a front portion thereof and a counterweight at a rear portion thereof. When the opening is formed in the second frame vertical plate for mounting the turning drive unit, the strength of the second frame vertical plate is reduced by that much.
In order to suppress the decrease in strength, the strength can be improved by increasing the thickness of the second frame vertical plate. In addition to or instead of this, a reduction in strength can be suppressed by reducing the opening area of the opening formed in the second frame vertical plate as much as possible.

For this purpose, the center line between the frame vertical plates is arranged at a position offset from the center of rotation of the revolving frame toward the side opposite to the cab by a predetermined distance. As a result, the turning wheel does not protrude too much outward from the position of the second frame vertical plate, so that the length of the turning drive unit protruding outward can be shortened. This can minimize the size of the opening. Further, the position of the center of gravity of the counterweight is positioned closer to the driver's cab than the center line between the frame vertical plates. as a result,
The load on the load of the front working machine and the counterweight is increased on the first frame vertical plate side where the opening is not formed, and the load on the second frame vertical plate can be reduced. Further, when the center of gravity of the counterweight is located at a position behind or near the turning center, the first and second
The distribution of the load to the frame vertical plate can be set more rationally.

The slewing drive unit is provided with a pedestal fixed on a slewing frame, and installed on the pedestal. The pedestal is disposed so as to cross the second frame vertical plate, and the second frame vertical plate has an opening. By forming a notch through the pedestal at the lower end of the portion, when the pedestal is fixed by welding means or the like, the welding line can be lengthened and the like, so that the pedestal can be fixed more firmly.

Here, the first and second frame vertical plates are generally formed as horizontal portions extending horizontally for a predetermined length from a portion connected to the counterweight, and furthermore, to prevent twisting. In order to achieve this, a horizontal portion is formed by connecting and providing reinforcing plates above and below the horizontal portion. Further, since a boom constituting a front working machine is mounted on the front portion of the frame vertical plate, a certain height is required. Therefore, this horizontal portion includes a rising portion curved forward and obliquely upward. However, depending on the shape of the second frame vertical plate, there is a possibility that the horizontal portion may interfere with any device arranged in the engine room, for example, an oil pan or the like. There is. Therefore, the height of the horizontal portion of the second frame vertical plate must be reduced. However, in terms of strength, assemblability, etc., the radius of curvature of the rising portion of the second frame vertical plate is
It is desirable that the radius of curvature of the rising portion of the first frame vertical plate be substantially the same. Under these conditions, in order to lower the height of the horizontal portion of the second frame vertical plate from the height position of the horizontal portion of the first frame vertical plate, the height of the horizontal portion of the second frame vertical plate should be changed from the horizontal portion to the rising portion. Of the first frame vertical plate is located on the rear side of the change point position from the horizontal portion to the rising portion of the first frame vertical plate. As a result, the distance from the opening to the rising portion can be increased, and the strength of the most disadvantageous portion can be improved.

The housing of the turning drive unit is fixed to the installation portion of the turning frame by a plurality of bolts. Since the turning drive unit passes through the second frame vertical plate, the pitch interval of the bolts for fixing the housing is set. When the opening of the second frame vertical plate and the vicinity thereof are set to the non-bolt mounting portion with the unequal pitch interval, the bolt can be easily attached and detached. When the rear end turning radius is reduced,
The space on the rear side of the turning frame is reduced. However, in the revolving frame, it is necessary to secure a space for mounting various devices and the like. For this reason, there is a case where it is not possible to secure a utility space for installing a storage section for tools and the like. Since the center line between the frame vertical plates is offset toward the opposite side to the cab, there is some space between the first frame vertical plate and the cab.
Therefore, this space can be used as a storage space for tools and the like.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The basic configuration of the hydraulic excavator is that the upper revolving unit is installed on the lower traveling unit via a revolving device, and that the upper revolving unit is provided with a front work machine and the like. It does not change substantially. Therefore, in order to allow the present invention to be more clearly understood, FIG. 1 shows a plan view of a revolving frame similar to FIG. 7, and the configuration of FIG. 1 is compared with the configuration of FIG. The features of the embodiment of the present invention will be described.

First, it is apparent from comparison of these figures that the turning frame 30 shown in FIG. 1 has a turning radius R from the turning center C to the rear end face of the arc-shaped counterweight 31. 7 is smaller than the turning radius r in FIG. In this way, by reducing the turning radius of the rear end, the possibility of collision with surrounding obstacles during turning of the upper turning body performed during excavation work is reduced, and even in a narrow place, such as excavation of soil and the like can be smoothly performed. Work can be done.

As described above, in order to shorten the rear end turning radius R in the turning frame 30, the counterweight 31 forming the rear end turning radius R is disposed more forward, and accordingly, the engine room 32 Is arranged forward in the turning frame 30 to a position overlapping with the position of the turning wheel 33 provided at the lower position. As a result, it is possible to bring the counterweight 31 closer to the turning center C, which is the center position of the through hole 34 where the center joint is mounted, in the turning frame 30. Therefore, the engine room 32 in the configuration of FIG. 1 is arranged at a position substantially corresponding to the utility space 16 and the hydraulic oil tank arrangement space 17 in the turning frame 4 of FIG.

The turning drive unit 35 of the turning device including the turning wheel 33 and the turning drive unit 35 cannot be disposed at a position where it interferes with the engine room 32. Here, although the pinion of the turning drive unit 35 needs to mesh with the ring gear of the inner ring of the turning wheel 33, it may be meshed at any position. In the turning frame 30 shown in FIG. 1, when the arrow F is set to the front of the vehicle in FIG. 1, the left side of the turning wheel 33 is provided with four anti-vibration support devices 36, and a driver's cab is disposed thereon. The turning drive unit 35 cannot be installed at this position because of the driver's cabin arrangement space 37, but it is possible to arrange the turning drive unit 35 at a position in front of the turning wheel 33. The turning drive unit 35 is a heavy object, and it is not preferable to dispose this heavy object in front of the turning center C in order to balance the entire vehicle. If such an arrangement is adopted, the weight of the counterweight 31 must be increased. Then, the counterweight 31 becomes large, which affects the rear end turning radius R. From the above, the turning drive unit 35 is arranged at the position on the right side of the turning frame 30 among the turning wheels 33 and obliquely rearward from the turning center C.

With this configuration, the turning drive unit 35 does not interfere with the engine room 32. In addition, the turning center C of the turning frame 30
Since the counterweight 31 is located at a more rearward position, there is no need to increase the size of the counterweight 31 and increase its weight.

In addition to the above, the hydraulic oil tank arrangement space 38 is disposed on the right side of the turning frame 30 in which the turning drive unit 35 is disposed, at a position adjacent to the turning drive unit 35. On the other hand, the fuel tank arrangement space 39 is arranged at a position behind the cab arrangement space 37. In the engine room 32, the hydraulic pump is provided at the right position, so the hydraulic oil tank arrangement space 38 is located close to the hydraulic pump, and the piping can be easily routed. Also, fuel tank arrangement space 3
9 is also located in the engine room 32 at a position close to the place where the engine is arranged, so that the piping can be easily routed. In the drawing, reference numeral 40 denotes an engine support provided at four locations. In the engine room 32, a heat exchanger is provided at a position on the left side of the engine arrangement portion, and a battery is provided at a position on the left side thereof. Further, a C / V arrangement space 41 in which a control valve and the like are arranged is formed in front of the hydraulic oil tank arrangement space 38.

A pair of left and right frame vertical plates 42a and 42b are provided on the revolving frame 30 to support a boom constituting a front working machine at a front portion and to support a counterweight 31 at a rear end portion. Is provided.
The frame vertical plate 42a is a first frame vertical plate located on the left side, and the frame vertical plate 42b is a second frame vertical plate located on the right side.

As shown in FIG. 2, the swing drive unit 3
5 is located on the right side of the turning frame 30, and the turning drive unit 35 is arranged at a position where it interferes with the second frame vertical plate 42b. Therefore, as shown in FIG. 3, an opening for passing a part of the housing of the turning drive unit 35 is provided between the lower end surface of the second frame vertical plate 42b and a predetermined height position. A part 43 is formed. The opening 43 is formed behind the position where the boom is attached to the second frame vertical plate 42b.

Moreover, the opening 43 not only secures a space for installing the turning drive unit 35, but also
This is also for forming a space necessary for allowing the turning drive unit 35 to be detachable. The turning drive unit 35 includes a pedestal 44 fixed to the turning frame 30.
Is fixed by tightening a predetermined number of bolts 45. In order to smoothly attach and detach the bolt 45 when removing the turning drive unit 35 and fasten the bolt 45 when re-attaching the turning drive unit 35, the second frame vertical plate 42b and the The bolts are not fixed to the wrapping position and the vicinity thereof, and the fixing pitch intervals of the bolts 45 are unequal pitch intervals as shown in FIG.

As described above, the pedestal 44 is for fixing the turning drive unit 35, and the turning drive unit 35 is arranged so as to pass through the opening 43 provided in the second frame vertical plate 42b. ing. Therefore, the pedestal 44 is also arranged to cross the opening 43. The notches 43a, 4 integral with the opening 43 are provided at the lower end position of the opening 43 provided in the second frame vertical plate 42b.
3a, the pedestal 44 is connected to the cutouts 43a, 43a.
a. As a result, pedestal 4
4 can be made large, and the pedestal 44 can be secured to the second frame vertical plate 42b using welding means, so that a sufficient length welding line can be secured.
4 can be fixed very firmly, and the fixability of the turning drive unit 35 is significantly improved.

However, if the turning drive unit 35 is lifted straight upward when attaching and detaching the turning drive unit 35, it will interfere with the second frame vertical plate 42b. Accordingly, in order to remove the turning drive unit 35, the turning drive unit 35 is lifted from the pedestal 44 to a predetermined height position in the opening 43, and is taken out while being inclined in the direction of the first frame vertical plate 42a. Therefore, it is somewhat troublesome to attach and detach the turning drive unit 35, but the frequency of removing the turning drive unit 35 from the turning frame 30 is extremely low. For this reason, it is sufficient that the turning drive unit 35 can be substantially detached and re-attached, and even if there is some trouble, no substantial inconvenience occurs.

As described above, the second frame vertical plate 42b
An opening 43 having a predetermined size is formed in the second frame vertical plate 42 when the opening area of the opening 43 is increased.
The strength of b decreases. Therefore, the opening area of the opening 43 is minimized. To do this, in FIG.
The center position of the turning wheels 33, i.e. with respect to the longitudinal direction of the pivot axis L ₁ of the vehicle including a turning center C, first, second frame vertical plate 42a, frame vertical plates centerline was aliquoted 42b L ₂ is offset to the right of the turning frame 30 by δ. Here, the larger the offset amount δ is, the more the position of the second frame vertical plate 42b is displaced to the end side of the turning wheel 33. Therefore, the amount of the turning drive unit 35 protruding from the second frame vertical plate 42b. Can be reduced, and as a result, the opening area of the opening 43 can be reduced. Here, since the offset amount δ needs to be a position where the trajectory of the movement of the bucket of the front work machine does not interfere with the crawler belt of the lower traveling body, it cannot be made extremely large.

The improvement of the strength of the second frame vertical plate 42b can also be achieved by increasing its thickness. However, if the thickness of the second frame vertical plate 42b is too large, the weight increases and the material cost increases,
In addition, processing becomes difficult. For this reason, the increase in the thickness of the second frame vertical plate 42b is suppressed to a minimum, the load on the second frame vertical plate 42b is reduced, and a larger load is applied to the first frame vertical plate 42a. By applying the load, the load share between the frame vertical plates 42a and 42b is changed. That is, the load on the first frame vertical plate 42a having a higher strength is greater than that on the second frame vertical plate 42b. For this, so that it is positioned at a position or near the center line L ₁ in the longitudinal direction of the vehicle including a turning center C of gravity position G of the counterweight 31. As a result, when an operation such as excavation of earth and sand is performed by the front working machine, the load acting on the frame vertical plates 42a and 42b becomes larger in the first frame vertical plates 42a, so that the openings 43 are formed. Frame vertical plate 42 whose strength has been reduced by
b can be prevented from being damaged or deformed.

By the way, as a result of forming the opening 43 in the second frame vertical plate 42b, this second frame vertical plate 42b is formed.
b has a weak portion in itself. That is, the portion where the distance between the end face of the second frame vertical plate 42b and the opening 43 is the shortest, specifically, the portion indicated by N in FIG. The width is reduced, and the strength of this portion is reduced. Therefore, by making the width dimension of the narrow portion N as large as possible, the reduction in strength is minimized.

Since the counterweights 31 are attached to the rear ends of the frame vertical plates 42a and 42b, a torsional force acts near the rear ends. Therefore, the rear portions of the frame vertical plates 42a, 42b are fixed to the upper and lower sides by means of welding or the like to form horizontal portions 42aI, 42bI having an I-shaped cross section. As shown in FIG. 1, the frame vertical plates 42a,
The front side of 42b has front mounting portions 42aF and 42bF which are wide mounting plate surfaces for connecting the boom and a hydraulic cylinder for driving the boom.
aI, 42bI to front mounting parts 42aF, 42bF
Are formed as rising portions 42aC and 42bC rising substantially in an arc shape. The radius of curvature of the rising portions 42aC and 42bC is made as large as possible, so that a sharp shape change point does not occur at the transition between them. Therefore, the rising portion 42a
The radii of curvature of C and 42bC are the frame vertical plates 42a and 42b.
It is extremely important in terms of the strength of the elements, and their radii of curvature are almost the same. Therefore, the second frame vertical plate 4
In 2b, in order to increase the width of the narrow portion N, it is not possible to reduce the radius of curvature of the rising portion 42bC so that the rising portion 42b suddenly rises.

As described above, in FIG. 4, the rising portion 4b extends from the horizontal portion 42bI of the second frame vertical plate 42b.
The transition point T ₁ to 2bC is defined as the transition point T from the horizontal portion 42aI of the first frame vertical plate 42a to the rising portion 42aC.
_The position is behind ₂ . However, the rising portion 42a
C, 42bC are connected to the front mounting portions 42aF, 4
The shape of 2bF is almost the same. For this reason, the horizontal section 4
Comparing the heights of 2aI and the horizontal portion 42bI, the horizontal portion 42bI on the second frame vertical plate 42b side is made lower. Thus, the transition point T ₁ of the transition point T ₂ at the rear, and by positioning the lower, both the rising portion 42
With the curvature radii of aC and 42bC being the same, the width dimension of the narrow portion N of the second frame vertical plate 42b can be increased. As already described, the horizontal portions 42aI, 42a
A counter weight 31 is connected to bI, and the center of gravity G of the counter weight 31 is
a, the second frame vertical plate 42
Even if the height of the horizontal portion 42bI on the b-side is reduced and the strength is somewhat reduced, the load is reduced, so that sufficient shape retention and stability can be obtained.

Since the height of the horizontal portion 42bI of the second vertical frame plate 42b is reduced, when the engine is installed in the engine room 32, it does not interfere with the oil pan 48 provided below the engine. It is more convenient because it can be at the height position.

Further, the frame vertical plates 42a and 42b are
The front mounting portions 42aF and 42bF and the horizontal portions 42aI and 42aI which substantially support the load of the counterweight 31 are provided.
The 42bI and the rising portions 42aC and 42bC are not usually formed as a single body from the viewpoint of machining or the like, but are each formed of a two-piece steel plate formed of separate members, and these are butted and welded by welding means. Will be linked. Therefore, the frame vertical plates 42a, 42b
Is formed so as to be inclined obliquely forward, thereby improving welding strength. In particular, as shown in FIG. 3, the second frame vertical plate 42b has an engine support portion. 40 can be provided so as not to interfere with the welding line W.

By the way, as compared with the turning frame 4 shown in FIG. 7, in the turning frame 30 of the present invention, the utility space 1 formed in the turning frame 4 is formed.
6 does not exist. The biggest reason for providing a utility space in a hydraulic shovel is to secure a storage space for tools and the like. Therefore, even if the utility space is not secured, if the arrangement portion of the tool box is secured, much inconvenience does not occur.

Thus, the first and second frame vertical plates 42
a, 42b to the fact that by offsetting the frame vertical plates centerline L ₂ which is equal to the right just rotating frame 30 [delta], as shown in FIG. 5, a first frame vertical plate 42a
The space between the driver's cab 49 and the driver's cab 49 installed in the driver's cab arrangement space 37 is increased. Therefore, it is possible to secure a space for installing the tool box 50 and the like at the portion at this interval.

[0042]

According to the present invention, the rear end turning radius can be significantly reduced without sacrificing the space for disposing the devices and the like installed on the turning frame. And so on.

[Brief description of the drawings]

FIG. 1 is a plan view of a turning frame of a hydraulic shovel according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of FIG. 1 showing a mounting part of the turning drive unit.

FIG. 3 is a perspective view of the position of FIG. 2 as viewed obliquely from the right.

FIG. 4 is an explanatory diagram of a main part configuration of a frame vertical plate.

FIG. 5 is a perspective view of a main part as viewed from the front in FIG. 1;

FIG. 6 is an external view of a conventional hydraulic excavator.

FIG. 7 is a plan view of a turning frame in the excavator of FIG. 6;

[Explanation of symbols]

REFERENCE SIGNS LIST 30 turning frame 31 counterweight 32 engine room 33 turning wheel 34 through hole 35 turning drive unit 37 driver's cab arrangement space 38 hydraulic oil tank arrangement space 39 fuel tank arrangement space 42a first frame vertical plate 42b second frame vertical plate 43 Opening 44 Base 45 Bolt 46, 47 Reinforcement plate 49 Operator's cab 50 Tool box C Center of rotation G Center of gravity L ₁ Center of rotation L ₂ Center line between vertical plates of frame R Turning radius T ₁ , T ₂ Transition point

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroki Sugawara 650, Kandamachi, Tsuchiura-shi, Ibaraki F-term in the Tsuchiura Plant of Hitachi Construction Machinery Co., Ltd. 2D015 DA01 DA04

Claims (9)

[Claims] A traveling vehicle in which an upper revolving structure is rotatably mounted on a lower traveling structure via a revolving device is provided with a pair of left and right frame vertical plates on a revolving frame constituting the upper revolving structure. A front work machine is mounted in front of the frame vertical plate, and a driver's cab is installed adjacent to the front work machine.Further, at the rear of the revolving frame, the rear end of the frame vertical plates is connected. A hydraulic excavator in which a rear end surface is provided with a counterweight having a substantially circular arc shape centered on the center of rotation of the upper revolving structure, wherein the revolving device includes a traveling body frame of the lower traveling structure and the revolving frame. And a ring gear provided on the turning frame, and a ring gear provided on an inner ring provided on the traveling body frame side of the turning wheel. And a turning drive unit including a motor that rotationally drives the pinion, wherein, of the pair of frame vertical plates, the frame vertical plate facing the operator's cab is a first frame vertical plate. When the frame vertical plate located on the opposite side to the operator's cab is a second frame vertical plate, the turning drive unit includes the first and second frame vertical plates.
The arrangement is such that it is arranged at a position on the side of the arrangement portion of the second frame vertical plate from the center line between the frame vertical plates that equally divides the interval between the frame vertical plates, and behind the turning center of the turning frame. A rear-end small turning hydraulic excavator characterized by the following features. 2. The turning frame is provided with an engine room for accommodating an engine or the like, the engine room is arranged at a position partially overlapping with the turning wheel, and the second frame vertical plate is provided on the second frame vertical plate. An opening is formed, and the turning drive unit is arranged at a position including the inside of the opening so as to overlap with the arrangement position of the second frame vertical plate. 1. A rear-end small turning hydraulic excavator according to 1. 3. The center line between the frame vertical plates is disposed at a position offset by a predetermined distance from the center of rotation of the revolving frame toward a side opposite to the driver's cab, and the center of gravity of the counterweight is provided. The rear-end small turning hydraulic excavator according to claim 2, wherein a position of the excavator is configured to be located on a side where the operator cab is disposed relative to a position of a center line between the frame vertical plates. 4. The small swing hydraulic excavator according to claim 3, wherein the center of gravity of the counterweight is located at a position behind or near the turning center. 5. The turning drive unit is mounted on a pedestal fixedly provided on the turning frame, and the pedestal is disposed so as to cross the second frame vertical plate, and is mounted on the second frame vertical plate. 3. The small rear turning hydraulic excavator according to claim 2, wherein a notch is formed at a lower end of the opening to allow the pedestal to pass therethrough. 6. The first and second frame vertical plates extend horizontally for a predetermined length from a connection portion to the counterweight, and have a horizontal portion provided with reinforcing plates above and below the horizontal portion. And a rising portion in which a front portion of the horizontal portion is bent obliquely upward. The curvature radius of the rising portion of the second frame vertical plate is equal to the curvature radius of the rising portion of the first frame vertical plate. The height of the horizontal portion of the second frame vertical plate is lower than the height of the horizontal portion of the first frame vertical plate, and the horizontal portion of the second frame vertical plate The point of change from
3. The rear-end small turning hydraulic excavator according to claim 2, wherein the first frame vertical plate is configured to be located rearward of a transition point from a horizontal portion to a rising portion. 7. The first and second frame vertical plates are divided into two portions at a transition portion from the rising portion to a mounting portion of the front work machine, and the connection at the transition portion is welding. 7. The small turning hydraulic excavator according to claim 6, wherein said welding line is inclined obliquely upward at a predetermined angle upward. 8. The housing of the turning drive unit,
A configuration is adopted in which the plurality of bolts are fixed to the installation portion of the turning frame, the pitch intervals of the bolts are unequal pitch intervals, and the opening of the second vertical frame plate and its vicinity are non-bolt mounting areas. 3. The small swing hydraulic excavator at the rear end according to claim 2, wherein 9. The first frame by offsetting a center line between the frame vertical plates toward a side opposite to the cab.
The rear end small turning hydraulic excavator according to claim 3, wherein an interval generated between the vertical frame plate and the operator cab is used as a storage space for tools and the like.