JPH11229433A - Revolving construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the total length of a revolving frame and reduce the total revolving radius and arrange compactly a plurality of hydraulic devices or the like on the revolving frame. SOLUTION: Overhanging beams 33, 34 provided between the center frame 30 of a revolving frame 22 and a side frame 36 are formed to have a larger height than the side frame 36, and a fuel tank is installed on the overhanging beams 33, 34. A container space 41 with a certain height positioned between the overhanging beams 33, 34 is formed under the fuel tank, and a cushion valve device 68 is arranged in the container space 41. In this way, the fuel tank and the cushion valve device 68 can be mutually stacked vertically and hence, a limited space on the revolving frame 22 can be effectively used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swing type construction machine such as a hydraulic shovel which is suitably used for excavating earth and sand, for example, and more particularly, to a swing type in which the swing radius of an upper swing body is reduced. Related to construction machinery.

[0002]

2. Description of the Related Art A hydraulic shovel will be described as an example of a conventional swing type construction machine with reference to FIG.

In FIG. 1, reference numeral 1 denotes a lower traveling body of a hydraulic shovel, and 2 denotes an upper revolving body which is rotatably mounted on the lower traveling body 1. A room 4, a building cover 5 containing a prime mover, a radiator, a hydraulic pump, and the like, a count weight 6, and the like are provided. And the revolving frame 3 of the upper revolving superstructure 2
Is provided with a turning device (not shown) including a turning motor or the like as a hydraulic actuator between the lower traveling structure 1 and the turning device. The turning device drives the upper turning structure 2 to turn around the turning center O. Has become.

The cab 4 is disposed at the front left side of the upper slewing body 2 and operates when the slewing operation of the upper slewing body 2 is performed.
Means that the left corner 4A of the front part has a radius R1 with respect to the turning center O.
Is turned along the virtual circle 7 of. The counterweight 6 is disposed on the rear side of the building cover 5 and is formed to be curved in an arc shape so as to be contained in an imaginary circle 8 having a radius R2 (R2> R1) with respect to the turning center O. .

[0005] Further, a fuel tank 9 is disposed on the revolving frame 3 on the right side of the upper revolving unit 2, and a hydraulic oil tank 10 is disposed between the fuel tank 9 and the building cover 5. A multiple valve device 11 is disposed between the operator's cab 4 and the fuel tank 9 at a position behind the turning center O. The multiple valve device 11 is used for traveling, working and turning. And the like.

Reference numeral 12 denotes a working device which is disposed at the front of the revolving frame 3 so as to be able to move up and down.
3, an arm, a bucket (both not shown) and the like are configured to excavate earth and sand. The boom 13 and the like of the working device 12 are arranged at positions offset by a certain distance from a center line O1-O1 passing through the turning center O in order to satisfy the standard dimensions of the cab 4.

[0007] A pair of boom cylinders 14, 14 as hydraulic actuators are provided between the boom 13 of the working device 12 and the front part of the turning frame 3, and the boom cylinders 14 move the boom 13 up and down. Is to be raised and lowered. The working device 12 is provided with an arm cylinder and a bucket cylinder (both not shown) as a hydraulic actuator in addition to the boom cylinder 14.

In the hydraulic excavator of the prior art constructed as described above, the upper swing body 2 is swiveled on the lower traveling body 1 by tilting an operation lever or the like provided in the operator's cab 4 and work is performed. The excavation work such as earth and sand is performed by raising and lowering the device 12. Then, at the time of the turning operation of the upper turning body 2, the corner 4A of the cab 4 is turned along the virtual circle 7 having the radius R1 with respect to the turning center O.

Further, the counterweight 6 is turned with respect to the turning center O along a virtual circle 8 having a radius R2.
Of the virtual circle 7 is larger than the radius R1 of the virtual circle 7 by the dimension ΔR. For this reason, when turning the upper swing body 2 at a work site or the like, the work is performed by turning the upper swing body 2 after confirming that there is no obstacle in the virtual circle 8 having the radius R2. The above safety is ensured.

[0010]

By the way, in the above-mentioned hydraulic shovel according to the prior art, when the upper swing body 2 is swung, an obstacle is formed within an imaginary circle 8 having a radius R2 determined by the rear side of the counterweight 6. It is necessary to confirm that the upper revolving unit 2 does not exist, and there is a problem that it is difficult to perform the revolving operation of the upper revolving unit 2 in a narrow work site or the like.

Therefore, the present inventors have studied to reduce the radius R2 from the turning center O to the rear surface side of the counterweight 6 to, for example, about the radius R1 on the cab 4 side.
Then, in this case, it is only necessary to confirm that the corner 4A in which the visibility can be sufficiently secured in front of the cab 4 does not interfere with surrounding obstacles or the like, and it is determined whether or not the turning operation of the upper turning body 2 is possible. This has the advantage that the safety of work can be easily ensured.

However, in this case, the counter weight 6
Is required to be shorter in order to bring the turning frame O closer to the turning center O, and the mounting space for hydraulic equipment and the like to be installed on the turning frame 3 is greatly limited.

In particular, as in a hydraulic circuit described in Japanese Utility Model Application Laid-Open No. 62-44105 (Japanese Utility Model Application Publication No. 3-2722), a directional control valve is switched by remote control means such as a pilot valve to switch from a hydraulic source. When the hydraulic oil is supplied to and discharged from the hydraulic actuator, if the switching speed of the directional control valve is too fast, an impact may occur when the hydraulic actuator is started or stopped. It is known to provide an impact mitigation means (switching speed adjusting means including a flow control valve with pressure compensation) between the pilot valve. These impact mitigation means are generally arranged on the rear side of the seat in the driver's cab.

However, as described above, when the entire length of the revolving frame 3 is reduced in order to reduce the entire revolving radius of the upper revolving unit 2, a prime mover, a radiator and the like are arranged behind the cab 4. Therefore, for example, it is not possible to provide the impact mitigation means behind the driver's cab 4, and there is a problem that it is very difficult to secure a mounting space.

Further, in a small turning machine having a small turning radius, in order to improve the livability and operability of the operator,
When the configuration is such that a driver's cab is provided which is the same as or the same as the standard machine, there is a problem that the installation space for various devices is narrowed and the layout at the time of design is difficult.

The present invention has been made in view of the above-described problems of the prior art, and the present invention can shorten the entire length of the revolving frame to reduce the entire revolving radius, and can secure a mounting space for impact mitigation means and the like. There is a need to provide a swivel type construction machine capable of easily performing piping work and the like.

Another object of the present invention is to provide a revolving construction machine capable of easily performing inspection work of an impact mitigation means (switching speed adjusting means) and improving the appearance of the machine. It is in.

[0018]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a first aspect of the present invention is to accommodate a lower traveling body, a driver's cab and a motor in a revolving frame mounted on the lower traveling body so as to be pivotable. Applied to a revolving construction machine that includes an upper revolving body provided with a building cover, a counterweight, a hydraulic oil tank, and a fuel tank, and a working device provided at the front of the upper revolving body so as to be able to move up and down. .

A feature of the structure adopted by the invention of claim 1 is that one of the hydraulic oil tank and the fuel tank is installed in the swivel frame with the bottom raised, and the tank and the swivel frame are mounted. A storage space is formed between the hydraulic actuator and the lower surface of the hydraulic actuator, and shock absorbing means for reducing the shock when the hydraulic actuator is started or stopped is provided in the storage space.

[0020] With this configuration, the tank and the shock absorbing means can be arranged so as to be stacked one above the other.
The limited space on the revolving frame can be effectively used. In addition, even if the entire length of the revolving frame is shortened, a space for mounting a plurality of hydraulic devices and the like can be secured, and the entire upper revolving unit can be accommodated within a small turning radius.

According to the second aspect of the present invention, the turning frame is provided with a directional control valve for switching and controlling the pressure oil from the hydraulic source and supplying and discharging the hydraulic oil to and from the hydraulic actuator. Remote control means for outputting a signal is provided, and the shock mitigation means is constituted by switching speed adjusting means for suppressing abrupt switching of the directional control valve by a switching signal from the remote control means.

Thus, even when the remote control means is suddenly operated, abrupt switching of the direction control valve can be suppressed by the switching speed adjusting means, and an impact is generated when the hydraulic actuator is started or stopped. Can be favorably alleviated.

Further, the invention of claim 3 provides a lower traveling body, a cab mounted on the lower traveling body so as to be capable of turning, a cab, a building cover for accommodating a motor, a counterweight, a hydraulic oil tank, and fuel. An upper revolving structure provided with a tank, and a working device provided in a front part of the upper revolving structure so as to be able to move up and down. On the revolving frame of the upper revolving structure, pressure oil from a hydraulic power source is switched and controlled. The present invention is applied to a turning type construction machine having a directional control valve for supplying and discharging to a hydraulic actuator, and remote control means for outputting a switching signal to the directional control valve in the cab.

A feature of the structure adopted by the invention of claim 3 is that one of the hydraulic oil tank and the fuel tank is installed in the swivel frame with the bottom raised, and the tank and the swivel frame are mounted. An accommodation space is formed between the lower surface of the directional control valve and a switching speed adjusting means for suppressing abrupt switching of the direction control valve by a switching signal from the remote control means. It is in.

With such a configuration, the tank and the switching speed adjusting means can be arranged so as to be stacked one above the other, and the limited space on the revolving frame can be effectively utilized. In addition, even if the entire length of the revolving frame is shortened, a space for mounting a plurality of hydraulic devices and the like can be secured, and the entire upper revolving unit can be accommodated within a small turning radius.

On the other hand, a fourth aspect of the present invention provides a lower traveling body,
An upper revolving structure provided with a driver's cab, a building cover for accommodating a prime mover, a counterweight, a hydraulic oil tank and a fuel tank on a revolving frame mounted on the lower traveling structure, and a front portion of the upper revolving structure; And a plurality of direction control valves for independently supplying and discharging hydraulic oil from a hydraulic source to a plurality of hydraulic actuators on a revolving frame of the upper revolving unit. The present invention is applied to a swing type construction machine provided with an interlocking device and a plurality of remote control means for individually outputting a switching signal to each directional control valve of the multi-valve device in the cab.

A feature of the structure adopted by the invention of claim 4 is that the multiple valve device is located on the front side of the revolving frame and is located in the left-right direction with respect to the cab with respect to the base end side of the working device. In the rear of the multiple valve device, one of the hydraulic oil tank and the fuel tank is installed with the bottom raised on the turning frame, and the tank and the lower surface of the turning frame And a plurality of switching speed adjusting means for suppressing abrupt switching of each of the directional control valves by a switching signal from each of the remote control means. And that

In this case, as in the third aspect,
The tank and the switching speed adjusting means can be arranged so as to be stacked one above the other, and the limited space on the revolving frame can be effectively utilized. By arranging the multiple valve device on the front side of the revolving frame and arranging the tank and the switching speed adjusting device on the rear side, the switching speed adjusting device can be arranged close to the multiple valve device and can be arranged in each direction. The switching speed of the control valve can be stably adjusted, and the work of drawing the hydraulic piping can be simplified.

According to the fifth aspect of the present invention, the revolving frame has left and right side frames extending in the front-rear direction, and the tank is arranged at a position higher than the upper surface of the side frame. An opening for inspecting the switching speed adjusting means in the housing space is provided between them, and a detachable cover for covering the opening from the outside is provided.

Thus, the opening provided between the side frame of the revolving frame and the tank can be used as an inspection port. After the inspection operation is completed, the opening is closed by the cover, thereby ensuring the safety and reliability of the machine. Can be improved.

Further, according to the invention of claim 6, the cover is
The bent shape corresponds to the outer shape of the tank and the side frame. As a result, the space between the side frame and the tank is covered with the cover, and the overall appearance thereof can be visually integrated.

In the invention according to claim 7, the remote control means comprises a pressure reducing valve type pilot valve for outputting a pilot pressure corresponding to the operation amount of the operation lever to the direction control valve as a switching signal, and the switching speed adjusting means is provided. And a flow control valve with pressure compensation for controlling the flow rate of pilot pressure supplied and discharged from the pilot valve to the directional control valve.

Thus, even if the operator of the machine suddenly tilts the operating lever or suddenly returns to the neutral position, the pilot pressure as a switching signal supplied / discharged from the pilot valve to the directional control valve is maintained. The rapid fluctuation can be mitigated by the flow control valve with pressure compensation, the switching speed of the directional control valve can be relatively slowed down, and the sudden start and stop operation of the hydraulic actuator can be suppressed well.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a swing type construction machine according to an embodiment of the present invention will be described in detail with reference to FIGS. In the present embodiment, the same components as those of the above-described related art are denoted by the same reference numerals, and description thereof will be omitted.

In the figure, reference numeral 21 denotes an upper revolving structure employed in the present embodiment. The upper revolving structure 21 is substantially the same as the upper revolving structure 2 described in the prior art, and includes a revolving frame 22, an operator's cab 23, and a motor described later. The structure includes a building cover 24 that accommodates 55 and the like, a counterweight 25, a fuel tank 26, and a hydraulic oil tank 27.

However, in this embodiment, the entire length of the revolving frame 22 is shortened, and accordingly, the shapes and arrangements of the building cover 24, the fuel tank 26 and the hydraulic oil tank 27 are changed as shown in FIG. Is what you are doing.

On the front side of the turning frame 22, a storage box 28 is disposed at a position opposite to the driver's cab 23 with respect to the base end side of the boom 13 in the left-right direction (right front position). In the storage box 28, a multiple valve device 59 described later and the like are stored. The upper revolving superstructure 21 includes a building cover 24, a counterweight 25, and a fuel tank 2.
6. Hydraulic oil tank 27, storage box 28, etc., together with corner 23A of operator's cab 23 are accommodated in a virtual circle 29 having a radius R3, and radius R3 of virtual circle 29 is the radius of virtual circle 7 described in the prior art. The dimensions are almost the same as R1.

Here, the turning frame 2 of the upper turning body 21
2, a center frame 30 as shown in FIG. 3 and projecting beams 31 projecting left and right from the center frame 30;
32, 33, 34 and the overhanging beams 31, 32, 33,
34, the left side frame 35 joined to the distal ends of the left overhanging beams 31 and 32 and extending in the front-rear direction, and the right side extended to the distal end side of the right overhanging beams 33 and 34 and joined in the forward and backward direction. The side frames 35 and 36 are formed of a high-strength pipe material having a D-shaped cross section as illustrated in FIG.

The center frame 30 of the revolving frame 22 has a center plate 30A made of a thick steel plate or the like.
And left and right center beams 30B and 30C joined on the center plate 30A and extending in the front-rear direction.
The front side of the center beams 30B, 30C is a bracket for the boom 13. Also, the center beam 30
The upper side of the tail plate 37 is joined to the rear side of B and 30C, and the left and right ends of the tail plate 37 are joined to the rear side of the side frames 35 and 36 by welding.

Further, a front support beam 38 for the operator cab 23 is joined to the front end of the side frame 35 between the side plate 35 and the center plate 30A, and the support beam 38, the projecting beams 31, 32, the side frame 35 and the like are connected. Fig. 3 on the top side
A driver's cab 23 is provided inside as indicated by a virtual line. On the other hand, the center plate 3
0A front support beam 39 for the storage box 28
And the bearing beam 39 and the side frame 36
The storage box 28 shown in FIG.

Reference numeral 40 denotes a front right lower surface plate which is located on the front side of the side frame 36 and is joined to the lower surfaces of the overhanging beam 33 and the support beam 39. It is substantially closed. Then, the rear end side of the lower plate 40 extends to a position of an accommodation space 41 described later, as shown in FIG.

Reference numeral 41 denotes a housing space formed between the overhanging beams 33 and 34. The housing space 41 has a structure in which a cushion valve device 68 described later is housed below the fuel tank 26 as shown in FIG. ing. Here, the overhang beam 33,
Numeral 34 is formed as a horizontal beam having an L-shaped cross section, and its height dimension is larger than the upper surface of the side frame 36 by a certain dimension as shown in FIG. The upper surfaces of the overhanging beams 33 and 34 constitute a mounting surface of the fuel tank 26, and are configured to support the fuel tank 26 in a state where the bottom 26A side is raised from the side frame 36.

Reference numeral 42 denotes a U-shaped bracket provided on the rear end side upper surface of the lower plate 40 in the accommodation space 41, and another bracket 43 provided on the lower side of the overhang beam 34. , The cushion valve device 68 is detachably held via bolts 44, 44,.... The bracket 43 is also formed of a U-shaped plate, and is located in the housing space 41 and joined to the inner surface of the overhang beam 34.

Reference numeral 45 denotes a mounting plate located below the bracket 43 and joined to the inner surface of the overhanging beam 34. The mounting plate 45 has an L-shaped cross section, and is provided with an under cover 46 to be described later. It is.

Reference numeral 46 denotes an under cover for closing the lower surface of the housing space 41. The under cover 46 is made of a thin steel plate or the like, and forms the lower surface of the revolving frame 22 below the housing space 41. The under cover 46 is provided between the rear end of the lower plate 40 and the mounting plate 45 by bolts 47, 47,
.. And the like. For example, at the time of inspection of the cushion valve device 68, a tool such as a wrench can be easily inserted into a bolt 51 described later in a detached state as shown in FIG. I have to.

Reference numerals 48, 48 denote mounting brackets located in the accommodation space 41 and joined to the inner surface of the side frame 36. Each of the mounting brackets 48 has a cross section L as shown in FIG.
The cover 50 is formed of a letter-shaped plate, and a cover 50 described later is attached thereto.

Reference numeral 49 denotes an opening formed between the upper surface of the side frame 36 and the bottom 26A of the fuel tank 26. The opening 49 allows the housing space 41 to communicate with the outside on the right side surface of the upper revolving unit 21, and provides a cushion valve. This constitutes an inspection port of the device 68.

A cover 50 detachably covers the opening 49 from the outside. The cover 50 is formed by bending a steel plate or the like into a substantially L-shape.
8 is detachably mounted on each bolt 8 using bolts 51.

The front end of the cover 50 is a bent portion 50A which is bent upward with a constant curvature, and the upper end of the bent portion 50A is at the bottom 26A of the fuel tank 26.
The folded portion 50B is folded inward in the vicinity. The bent portion 50A of the cover 50 has a bent shape corresponding to both the side frame 36 and the fuel tank 26, and has a configuration in which these outer shapes have a visual sense of unity. I have.

A mounting bracket 52 is located on the rear side of the side frame 36 and joined to the rear side of the overhanging beam 34. The mounting bracket 52 operates together with the mounting bracket 53 on the tail plate 37 shown in FIG. Oil tank 2
7 constitute a mounting surface.

Reference numeral 54 denotes a turning motor as a hydraulic actuator disposed at the center of the center frame 30. The turning motor 54 is constituted by a hydraulic motor, and is connected to a center plate via a turning speed reducer (not shown). Mounted on 30A. The swing motor 54 drives the upper swing body 21 to swing on the lower traveling body 1 via a speed reducer by supplying and discharging pressure oil from a hydraulic pump 56 described later.

Reference numeral 55 denotes a prime mover provided in the building cover 24 of the upper revolving unit 21; 56, a hydraulic pump driven by the prime mover 55; the hydraulic pump 56 constitutes a hydraulic source together with the hydraulic oil tank 27; As shown in (1), the hydraulic oil in the hydraulic oil tank 27 is discharged as high-pressure oil.

57A and 57B are main pipelines as a pair of oil passages connecting the hydraulic pump 56 and the hydraulic oil tank 27 to the boom cylinder 14, and 58 is a boom direction provided in the middle of the main pipelines 57A and 57B. A directional control valve 5
Reference numeral 8 denotes a hydraulic pilot type directional control valve, which has hydraulic pilot portions 58A and 58B on both the left and right sides. The direction control valve 58 is switched from the neutral position (a) to the switching position (b) or (c) by a pilot pressure from a pilot valve 61 described later, and the boom cylinder 14 is operated by the hydraulic oil from the hydraulic pump 56. It is to let.

Reference numeral 59 denotes a multiple valve device comprising a directional control valve 58 and the like. The multiple valve device 59 includes, in addition to the directional control valve 58 for the boom 13, an arm, a bucket, a swing and a traveling. It is configured as a control valve block including a directional control valve (neither is shown). And the multiple valve device 5
9 is a storage box 2 located on the front side of the revolving frame 22.
8.

Reference numeral 60 denotes a pilot pump driven by the prime mover 55 together with the hydraulic pump 56; 61, a pressure-reducing valve type pilot valve which constitutes a remote control means provided in the cab 23; While being connected to the pump 60, a tank port is connected to the hydraulic oil tank 27, and a pair of output ports are connected to hydraulic pilot portions 58A, 58B of the direction control valve 58 via pilot lines 62A, 62B.

The pilot valve 61 outputs a pilot pressure corresponding to the operation amount as a switching signal when the operator tilts the operation lever 61A in the cab 23. Further, in the operator's cab 23, a pilot valve for switching the direction control valve for the arm, the bucket, the turning and the traveling, and the like is provided as a remote control means. The pilot lines 62A and 62A are also provided between the pilot valves and the directional control valves.
A pilot line similar to 2B is provided, and the entire pilot line 62 is shown by a dashed line in FIG.

63A and 63B are pilot pipes 62A,
A cushion valve as a flow control valve with pressure compensation disposed in the middle of the cushion valve 63A (6B).
3B) is a valve casing 64 having pilot pressure inflow / outflow ports 64a and 64b and a spool sliding hole 64c as shown in FIG. 8, and a spool inserted into the spool sliding hole 64c of the valve casing 64. 65 and the spool 6
5 comprises springs 66 and 67 which are constantly biased toward the neutral position shown in FIG.

The cushion valves 63A, 63B
Is described in, for example, Japanese Utility Model Laid-Open No.
No. 22) It is configured similarly to that described in the gazette.

Here, the spool 65 has oil passages 65a and 65b spaced apart in the axial direction.
A stop 65c is formed between the stop 65a and the stop 65c.
The spool 65 is moved by the pressure difference generated before and after
It is slid in the directions indicated by arrows A and B in the middle. The inflow / outflow ports 64a, 64b of the valve casing 64 are located in the middle of the pilot pipe line 62A (62B), and the pilot pressure from the pilot valve 61 is applied to the oil passages 65a, 65 of the spool 65.
b, the hydraulic pilot portion 58A (58B) of the direction control valve 58 is supplied and discharged through the throttle 65c.

Then, for example, the operation lever 61A is tilted from the neutral position, and the pilot pressure from the pilot valve 61 is applied to the hydraulic pilot portion 58A (58) of the direction control valve 58.
B), the oil liquid flows from the oil passage 65a toward the oil passage 65b. If a pressure difference occurs before and after the throttle 65c at this time, the spool 65 springs It is displaced in the direction of arrow A against 67. Then, the spool 65 reaches the vicinity of the stroke end and causes a response delay until the oil passages 65a and 65b directly communicate with each other through the outer peripheral surface of the spool 65. Thus, even when the operation lever 61A is suddenly operated, the pilot pressure is reduced. To prevent a sudden increase.

When the operating lever 61A is returned to the neutral position, the oil is directed from the hydraulic pilot portion 58A (58B) of the direction control valve 58 toward the pilot valve 61 and from the oil passage 65b toward the oil passage 65a. The liquid circulates,
Also at this time, if a differential pressure occurs before and after the throttle 65c,
As a result, the spool 65 is displaced in the direction of arrow B against the spring 66. Then, the spool 65 reaches the vicinity of the stroke end and causes a response delay until the oil passages 65b and 65a are directly communicated with each other through the outer peripheral surface of the spool 65, so that even when the operation lever 61A suddenly returns, the pilot pressure is reduced. To prevent rapid decrease.

Thus, the cushion valves 63A, 63
B controls the flow rate of the pilot pressure supplied to and discharged from the directional control valve 58 from the pilot valve 61, suppresses rapid fluctuations in the pilot pressure, and performs pressure compensation. That is, when the operator in the cab 23 rapidly tilts the operation lever 61A of the pilot valve 61 or suddenly returns to the neutral position, the cushion valves 63A, 6
3B constitutes a switching speed adjusting means for alleviating a sudden change in the pilot pressure supplied and discharged from the pilot valve 61 to the directional control valve 58 and suppressing an excessively high switching speed of the directional control valve 58. , And constitutes impact relaxation means for reducing the impact when the boom cylinder 14 is started or stopped.

Reference numeral 68 denotes a cushion valve device composed of cushion valves 63A, 63B and the like. The cushion valve device 68 is a cushion valve 6 for the boom 13.
In addition to 3A and 63B, it is configured as a valve block including cushion valves for arm, bucket, turning and running (neither is shown). Also, a bracket plate 69 is provided on the bottom side of the cushion valve device 68 as shown in FIGS.
Are fastened to the brackets 42 and 43 with bolts 44 and the like.

As a result, the cushion valve device 68
Is disposed in a housing space 41 formed between the projecting beams 33 and 34 of the revolving frame 22 as shown in FIGS. The cushion valve device 68 is provided with a plurality of connection ports 68a, 68a,..., And each of the connection ports 68a is connected to an intermediate portion of the pilot pipe 62 including the pilot pipes 62A and 62B. is there.

The hydraulic shovel according to the present embodiment has the above-mentioned configuration, and its basic operation is not particularly different from that of the prior art.

According to this embodiment, however, the projecting beams 33 and 34 provided between the center frame 30 and the side frames 36 of the revolving frame 22 are larger than the side frames 36 as shown in FIG. Formed to height dimensions,
The fuel tank 26 is installed on the overhanging beams 33 and 34, and the overhanging beams 33 and 34 are provided below the fuel tank 26.
As shown in FIG. 4, a storage space 41 having a certain height is formed between the storage tanks 41, and a cushion valve device 68 is disposed in the storage space 41.
6 and the cushion valve device 68 can be arranged so as to be stacked one above the other, and the limited space on the revolving frame 22 can be effectively utilized.

A storage box 28 is disposed at the front side of the revolving frame 22 at a position opposite to the driver's cab 23 in the left-right direction with respect to the base end of the boom 13 as a center (reference). The multiple valve device 59 is disposed in the inside, and the fuel tank 26 and the cushion valve device 68 are disposed behind the storage box 28. Therefore, the cushion valve device 68 is connected to the multiple valve device 59. The pilot pipe 62 drawn from the cab 23 (pilot valve 61) is relayed to the multiple valve device 59 through the cushion valve device 68 as illustrated in FIG. And can be easily routed.

As a result, the pilot pressure relayed through the cushion valve device 68 is applied to the directional control valve 58 of the multiple valve device 59.
The switching speed of the direction control valve 58 can be stabilized and adjusted, and the work of drawing the hydraulic piping including the pilot pipeline 62 can be simplified.

Further, the multiple valve device 5 is mounted on the revolving frame 22.
9. By arranging the fuel tank 26, the cushion valve device 68, and the like as described above, the overall length of the revolving frame 22 can be reliably reduced.
The whole can be accommodated in an imaginary circle 29 having a radius R3 shown in FIG. 2 and the turning radius can be reduced, and a plurality of hydraulic devices and the like can be arranged in a limited space of the turning frame 22, so that a mounting space can be secured. .

Further, as shown in FIG. 6, an opening 49 is provided between the side frame 36 of the revolving frame 22 and the fuel tank 26, and a cover 50 for opening and closing the opening 49 is attached to the side frame 36. Bracket 48
6, the opening 49 can be used as an inspection port by detaching and attaching the cover 50 with the under cover 46 removed as shown in FIG. The cushion valve device 68 can be easily inspected from outside the upper swing body 21.

In this case, since many pipes and wirings such as the pilot pipe line 62 are attached to the cushion valve device 68, it is an important place to be checked when the machine is abnormal, etc. Cover 5 during inspection work including
The fact that 0 can be removed is a great advantage.

Further, by closing the opening 49 with the cover 50 after the completion of the inspection work, safety as a construction machine can be secured and reliability can be improved. The cover 50 having a bent shape corresponding to the outer shape of the fuel tank 26 and the side frame 36 is shown in FIG.
Since the space between the side frame 36 and the fuel tank 26 is covered with the cover 50 as shown in FIG.

Therefore, according to the present embodiment, the overall length of the revolving frame 22 can be reduced, the revolving radius of the entire upper revolving unit 21 can be reliably reduced, and the cushion valve device can be installed in a limited space of the revolving frame 22. A mounting space such as 68 can be secured, and piping work for relaying the cushion valve device 68 between the cab 23 and the multiple valve device 59 can be easily performed.

Further, the inspection work of the cushion valve device 68 can be easily performed by the detachable cover 50, and the workability at the time of inspection can be improved. Further, by covering the space between the side frame 36 and the fuel tank 26 with the cover 50, the overall appearance thereof can have a visual sense of unity, and the aesthetic appearance of the hydraulic shovel can be improved. is there.

Further, even if the operator in the cab 23 suddenly operates the operation lever 61A or suddenly returns to the neutral position, the directional control valve 5
8 can be mitigated by the cushion valve devices 68 such as the cushion valves 63A and 63B, so that the switching speed of the direction control valve 58 can be made relatively slow, and the boom can be reduced. Cylinder 1
The hydraulic actuator such as 4 can be suppressed from being suddenly started or stopped, and the operation of the hydraulic actuator can be stabilized.

In the above embodiment, the fuel tank 2
6, the housing space 41 is formed below, but instead, for example, a housing space is formed below the hydraulic oil tank 27, and the switching speed of the cushion valve device 68 and the like is formed in this housing space. It is good also as a structure which arranges adjustment means.

Further, in the above-described embodiment, the excavator has been described as an example. However, the present invention is not limited to this. For example, a wheel-type excavator or a self-propelled crane may be provided. The present invention may be applied to a rotating construction machine.

[0078]

As described in detail above, according to the first aspect of the present invention, one of the hydraulic oil tank and the fuel tank is installed on the revolving frame with the bottom raised, and the tank is revolved with the revolving frame. A housing space is formed between the lower surface of the frame and the housing space, and shock absorbing means for starting or stopping the hydraulic actuator is provided in the housing space. Therefore, the tank and the shock absorbing means are stacked up and down. In this manner, the limited space of the revolving frame can be effectively used, and the occurrence of an impact or the like at the time of starting or stopping the hydraulic actuator can be favorably reduced. And the entire length of the revolving frame can be shortened, and the revolving radius of the entire upper revolving structure can be surely reduced.
It is possible to compactly store a plurality of hydraulic devices and the like including the shock absorbing means in a limited space of the turning frame.

According to the second aspect of the present invention, the shock absorbing means is constituted by the switching speed adjusting means for suppressing abrupt switching of the directional control valve by the switching signal from the remote operating means. As a result, the switching speed of the directional control valve can be prevented from becoming too fast, and the impact of starting and stopping the hydraulic actuator can be reduced, and the operation of the hydraulic actuator can be stabilized.

Further, according to the third aspect of the present invention,
Either the hydraulic oil tank or the fuel tank is installed on the revolving frame with the bottom raised, and a storage space is formed between the tank and the lower surface of the revolving frame. Since the switching speed adjusting means for suppressing the sudden change of the direction control valve by the switching signal from the operating means is arranged, the tank and the switching speed adjusting means can be arranged to be stacked one above the other, The limited space of the turning frame can be effectively used. Therefore, the total length of the revolving frame can be reduced, the revolving radius of the entire upper revolving unit can be reliably reduced, and a plurality of hydraulic devices and the like can be compactly stored in the limited space of the revolving frame.

On the other hand, according to the invention of claim 4, the multiple valve device is disposed on the front side of the revolving frame at a position opposite to the cab with respect to the base end side of the working device. Behind the tank, one of the hydraulic oil tank and the fuel tank is installed with the bottom raised on the revolving frame, and in the accommodation space between the tank and the revolving frame, switching from each remote control means is performed. Since a plurality of switching speed adjusting means for suppressing abrupt switching of each directional control valve by a signal is provided, the tank and the switching speed adjusting means are moved up and down in the same manner as in the third aspect of the invention. They can be arranged in a stack so that the limited space of the revolving frame can be used effectively. By arranging the multiple valve device in front of the revolving frame and arranging the tank and the switching speed adjusting device on the rear side, the switching speed adjusting device can be arranged close to the multiple valve device, and the operator's cab A pipe work or the like for relaying the switching speed adjusting means between the apparatus and the multiple valve device or the like can be easily performed, and a work for drawing the hydraulic pipe can be simplified.

According to the fifth aspect of the present invention, an opening is provided between the side frame and the tank for checking the switching speed adjusting means in the housing space, and a detachable cover for covering the opening from the outside is provided. With this configuration, the opening between the side frame and the tank can be used as an inspection port, and the safety and reliability of the machine can be improved by closing the opening with a cover after the completion of the inspection work.

Further, in the invention according to claim 6, since the cover is formed with a bent shape corresponding to the outer surface shape of the tank and the side frame, the space between the side frame and the tank is covered with the cover, and the entirety thereof is covered. It is possible to give a visual sense of unity to various external shapes and improve the aesthetic appearance of the machine.

According to the seventh aspect of the present invention, the remote control means is a pressure reducing valve type pilot valve, and the switching speed adjusting means is a pressure compensating means for controlling the flow rate of the pilot pressure supplied and discharged from the pilot valve to the directional control valve. The switching signal is supplied and discharged from the pilot valve to the directional control valve even if the operator of the machine suddenly tilts the operating lever or suddenly returns to the neutral position. The sudden fluctuation of the pilot pressure can be mitigated by the flow control valve with pressure compensation, the switching speed of the directional control valve can be made relatively slow, and the sudden start and stop operation of the hydraulic actuator can be suppressed well. it can.

[Brief description of the drawings]

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

FIG. 2 is an enlarged plan view of the upper swing body and the like of the excavator in FIG. 1;

FIG. 3 is an enlarged plan view showing a revolving frame.

FIG. 4 shows an arrow IV in FIG. 3 showing a cushion valve device and the like.
FIG. 4 is an enlarged sectional view as viewed from −IV.

FIG. 5 is a cross-sectional view as seen from a direction indicated by arrows VV in FIG. 4;

FIG. 6 is an enlarged cross-sectional view showing a side frame, a fuel tank, a cover, and the like, as viewed from a direction indicated by arrows VI-VI in FIG.

FIG. 7 is a hydraulic circuit diagram showing a boom cylinder, a direction control valve, a pilot valve, a cushion valve, and the like.

FIG. 8 is an enlarged longitudinal sectional view showing a cushion valve in FIG. 7;

FIG. 9 is a plan view showing a conventional hydraulic excavator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Lower traveling body 12 Work device 13 Boom 14 Boom cylinder 21 Upper revolving body 22 Revolving frame 23 Operator's cab 24 Machine room 25 Counter weight 26 Fuel tank 27 Hydraulic oil tank 28 Storage box 29 Virtual circle 30 Center frame 33, 34 Overhang beam 35, 36 Side frame 41 Housing space 42, 43 Bracket 46 Under cover 48 Mounting bracket 49 Opening 50 Cover 56 Hydraulic pump (hydraulic source) 57A, 57B Main pipeline 58 Direction control valve 59 Multiple valve device 61 Pilot valve (remote control means) ) 62, 62A, 62B Pilot line 63A, 63B Cushion valve (flow control valve with pressure compensation) 68 Cushion valve device (switching speed adjusting means) 69 Bracket plate R3 Radius (turning radius) O Turning center

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Tsuyoshi Ueki 938-1 Ma, Shimoichi, Kasama City, Ibaraki Prefecture

Claims (7)

[Claims] 1. A revolving superstructure comprising: a lower traveling body; a cab, a building cover for accommodating a prime mover, a counterweight, a hydraulic oil tank, and a fuel tank mounted on the lower traveling body so as to be pivotable on the lower traveling body. And a working device provided at the front of the upper revolving body so as to be capable of raising and lowering, wherein one of the hydraulic oil tank and the fuel tank is raised to the revolving frame. Installed in the state,
An accommodating space is formed between the tank and the lower surface of the revolving frame, and shock absorbing means for alleviating an impact when the hydraulic actuator is started or stopped is provided in the accommodating space. And revolving construction machinery. 2. The swing frame is provided with a directional control valve for switching control of hydraulic oil from a hydraulic source to supply and discharge the hydraulic oil to and from a hydraulic actuator, and outputs a switching signal to the directional control valve in the cab. 2. The swiveling type as claimed in claim 1, further comprising remote control means, wherein said shock absorbing means is constituted by switching speed adjusting means for suppressing abrupt switching of said directional control valve by a switching signal from said remote control means. Construction machinery. 3. An upper revolving structure having a lower traveling structure, a driver's cab, a building cover for accommodating a motor, a counterweight, a hydraulic oil tank, and a fuel tank mounted on a revolving frame rotatably mounted on the lower traveling structure. And a working device provided at the front of the upper revolving unit so as to be capable of raising and lowering. A direction in which pressure oil from a hydraulic power source is switched to the revolving frame of the upper revolving unit to supply and discharge the hydraulic actuator. A swing construction machine comprising a control valve, and remote control means for outputting a switching signal to the direction control valve in the cab, wherein one of the hydraulic oil tank and the fuel tank is Installed with the bottom raised on the revolving frame,
A housing space is formed between the tank and the lower surface of the revolving frame. In the housing space, a switching speed is controlled to prevent the directional control valve from being rapidly switched by a switching signal from the remote control means. A revolving construction machine, characterized in that it is provided with means. 4. A revolving superstructure comprising: a lower traveling structure; a cab, a building cover for accommodating a prime mover, a counterweight, a hydraulic oil tank, and a fuel tank mounted on the lower traveling structure so as to be pivotable on the lower traveling structure. And a working device provided at the front of the upper revolving unit so as to be able to move up and down. The pressurized oil from a hydraulic source is independently supplied to and discharged from a plurality of hydraulic actuators to a revolving frame of the upper revolving unit. A swiveling type comprising a multiple valve device comprising a plurality of directional control valves, and a plurality of remote control means for individually outputting a switching signal to each directional control valve of the multiple valve device in the cab. In the construction machine, the multiple valve device is located on the front side of the revolving frame and is disposed on the opposite side in the left-right direction with respect to the cab with respect to a base end side of the working device, and is located behind the multiple valve device. The hydraulic oil tank One of the fuel tanks is installed with the bottom raised on the revolving frame, and a storage space is formed between the tank and the lower surface of the revolving frame. A turning type construction machine comprising a plurality of switching speed adjusting means for suppressing abrupt switching of each of the directional control valves by a switching signal from an operating means. 5. The revolving frame has left and right side frames extending in the front-rear direction, the tank is disposed at a position higher than an upper surface of the side frame, and a space between the side frame and the tank is provided. 5. The revolving construction machine according to claim 2, wherein an opening for checking the switching speed adjusting means in the accommodation space is provided, and a detachable cover for covering the opening from outside is provided. 6. The swiveling construction machine according to claim 5, wherein the cover has a bent shape corresponding to the outer surface shape of the tank and the side frame. 7. The remote control means comprises a pressure reducing valve type pilot valve for outputting a pilot pressure corresponding to an operation amount of an operation lever to the direction control valve as a switching signal, and the switching speed adjusting means comprises a pilot valve. 7. The swing type construction machine according to claim 2, further comprising a flow control valve with pressure compensation for controlling a flow rate of a pilot pressure supplied to and discharged from the direction control valve.