JP4305824B2 - Piping structure in construction machinery - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of piping structures in construction machines such as hydraulic excavators.
[0002]
[Prior art]
Generally, a front mounted on a construction machine such as a hydraulic excavator is provided with a hydraulic actuator such as a hydraulic cylinder, and is configured to be able to perform work by the front based on pressure oil supply to the hydraulic actuator. However, in this case, the hydraulic piping that becomes the flow path of the pressure oil from the hydraulic device mounted on the machine body side to the hydraulic actuator on the front side is configured to be able to cope with the vertical swing of the front accompanying the work. There is a need. For this reason, the hydraulic piping is, for example, a flexible body interposed between the airframe side piping fixed to the airframe side, the front side piping fixed to the front side, and the airframe side piping and the front side piping. The hydraulic hose has a property to be able to cope with the vertical swing of the front by the deformation of the hydraulic hose that extends or bends. However, in this case, when the hydraulic hose stretches or bends as the front moves up and down, the part where the bending angle of the hydraulic hose changes greatly, for example, both ends of the hydraulic hose (with the fuselage side piping and the front side piping) Stress tends to concentrate on the hydraulic hose portion in the vicinity of the connecting portion, and there is a risk that the portion will deteriorate early. Also, care must be taken so that the bent hydraulic hose does not interfere with other parts of the construction machine.
Therefore, the fuselage side pipe fixed to the fuselage side and the hydraulic hose extending to the front side are connected via a swivel joint, while the middle part of the hydraulic hose is inserted into the hose guide fixed to the front so as to be movable in the longitudinal direction. There is a configuration in which the hydraulic hose portion above the hose guide is bent (see, for example, Patent Document 1).
In addition, a swivel joint is arranged coaxially with a bearing that pivotally supports the front to the body side so as to be movable up and down, and the swivel joint is connected to the body side pipe fixed to the body side and the front side pipe fixed to the front side. Some of them are configured to be able to cope with the vertical swing of the front by rotating the swivel joint (for example, see Patent Document 2).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-266260 (page 3, FIG. 7, FIG. 9)
[Patent Document 2]
JP 2000-282508 A [0004]
[Problems to be solved by the invention]
By the way, in Patent Document 1, when the front swings up and down, the hydraulic hose moves in the longitudinal direction while being guided by the hose guide so that the hydraulic hose portion below the hose guide becomes substantially linear. However, in this case, the hydraulic hose moves in the hose guide every time the front moves up and down, so the hydraulic hose and the hose guide rub against each other, causing premature damage to the hydraulic hose. is there.
On the other hand, there is no problem of damage to the hydraulic hose in Patent Document 2 because there is no hydraulic hose that bends or moves as the front moves up and down. It is indispensable to provide a swivel joint coaxially with a support shaft that is pivotally supported. Therefore, in Patent Document 2, a pair of left and right mounting portions are provided at the base end portion of the front, and the left and right mounting portions are respectively connected to left and right mounting brackets protruding from the body side via left and right support shafts. A swivel joint was arranged between the left and right support shafts. For this reason, the support shaft that pivots the front to the machine body is divided into two parts on the left and right, but the front shaft support is a part that requires high strength because of the work load. There is a problem that it is not preferable from the viewpoint of strength to divide the support shaft of the part into two, and there is a problem to be solved by the present invention.
[0005]
[Means for Solving the Problems]
The present invention has been made in view of the above circumstances and has been created for the purpose of solving these problems. The invention according to claim 1 provides a base end portion of a front equipped with a hydraulic actuator, In a construction machine that is pivotally supported by left and right mounting seat frames projecting from the upper and lower pivots, a hydraulic pipe serving as a pressure oil passage from a hydraulic device provided on the machine body side to the hydraulic actuator is connected to the machine body side. The main body side pipe fixed to the front side, the front side pipe fixed to the front side, and a flexible hydraulic hose interposed between the main body side pipe and the front side pipe. per, by arranging so as to be positioned between the body of the left and right sites and connected to the hydraulic hose pipe and portion to be connected to the hydraulic hoses of the front pipe in plan view the mounting seat frame, the hydraulic hoses Together to be positioned between the left and right mounting seat frame in a plan view, connected via a swivel joint located between the hydraulic hoses and the inboard pipeline or front side piping between the left and right mounting seat frame, front In the state where the hydraulic hose is moving downward, the hydraulic hose is positioned between the left and right mounting seat frames and is substantially linear, and in the state where the front is moving upward, the central part of the hydraulic hose is bent downward and The piping structure in a construction machine is characterized in that the bent portion is housed in a space between the left and right mounting seat frames so that both end portions of the hydraulic hose are hardly bent .
By doing this, it is possible to avoid problems such as the flexed hydraulic hose interfering with other parts of the construction machine or stress is concentrated on a part of the hydraulic hose and the part deteriorates early. Can contribute to improving the durability of the hydraulic hose.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings. In the drawings, reference numeral 1 denotes a hydraulic excavator. The hydraulic excavator 1 is attached to a crawler type lower traveling body 2, an upper revolving body 3 that is rotatably supported by the lower traveling body 2, and the upper revolving body 3. The front 4 includes a boom 5, an arm 6, a bucket 7, and the like, and includes hydraulic actuators such as an arm cylinder 8 and a bucket cylinder 9. The arm cylinder 8 and the bucket cylinder 9 are expanded and contracted based on the supply and discharge of pressure oil made via a front hydraulic pipe 10 to be described later, whereby the arm 6 and the bucket 7 operate. The construction is the same as before.
[0007]
Here, the base end portion of the boom 5 constituting the front 4 is located between the pair of left and right mounting seat frames 11, 11 protruding integrally with the base frame 3 a of the upper swing body 3. The shafts 11 and 11 and the boom 5 are formed so as to be swingable up and down via a support shaft 12 that passes through a boss cylinder 5a formed at the base end of the boom 5. The boom 5 is configured to swing up and down about the support shaft 12 based on the expansion and contraction operation of the boom cylinder 13. The hydraulic pipe (see FIG. (Not shown) is arranged below the boom 5 and is not included in the hydraulic piping of the present invention.
[0008]
Reference numeral 14 denotes a turning motor (with a speed reducer) for turning the upper turning body 3. The turning motor 14 is located between the left and right mounting seat frames 11, 11 and the base end of the boom 5. It is arrange | positioned in the back position.
[0009]
Reference numeral 15 denotes a control valve disposed on the upper rear side of the swing motor 14, and the control valve 15 includes various types including the arm cylinder 8, bucket cylinder 9, boom cylinder 13, and swing motor 14. A plurality of valves for controlling pressure oil supply / discharge to the hydraulic actuator are incorporated as a unit, and hydraulic equipment such as a hydraulic pump, an oil tank, and a hydraulic actuator (not shown) are connected via a pipe. .
[0010]
On the other hand, the front hydraulic pipe 10 is a plurality of pipes serving as pressure oil supply / discharge passages from the control valve 15 to the arm cylinder 8 and bucket cylinder 9 provided on the front 4. The pipe 10 has one end side connected to the control valve 15 and the other end side located above the left and right mounting seat frames 11, 11, a metal body side pipe 10 </ b> A, and one end side of the boss cylinder 5 a having a boom base end. Between the front side pipe 10B which is fixed in the vicinity via a clamp 16 and whose other end side is connected to the arm cylinder 8 or the bucket cylinder 9, and between the other end side of these machine body side pipes 10A and one end side of the front side pipe 10B. And a flexible hydraulic hose 10C interposed between the airframe 10A and the hydraulic hose 10C. , The swivel joint (swivel) 17 is disposed. As is apparent from FIGS. 3, 5, 6, 7, and 8, the portion (the other end side) connected to the hydraulic hose 10C of the machine body side piping 10A and the hydraulic hose 10C of the front side piping 10B are connected. Similar to the hydraulic hose 10C, the part (one end side) is located between the left and right mounting seat frames 11 when viewed in plan.
In the present embodiment, the arm cylinder 8 and the bucket cylinder 9 are shown as the hydraulic actuators mounted on the front 4, and four convenient pipes for the arm cylinder and the bucket cylinder are shown as the front hydraulic pipe 10. However, without being limited thereto, for example, when the front 4 is equipped with a hydraulic actuator such as a breaker, the front hydraulic pipe 10 may include a pipe for the hydraulic actuator.
[0011]
The swivel joint 17 includes a first joint 17A having a connection port 17a to which the other end of the machine body side pipe 10A is connected, a second joint 17B having a connection port 17b to which the hydraulic hose 10C is connected, The first and second joints 17 </ b> A and 17 </ b> B are configured using a connecting portion 17 </ b> C that rotatably connects the two joint ports 17 </ b> A and 17 </ b> B. It is communicated through. Thus, the hydraulic hose 10 </ b> C is connected to the other end side of the machine body side pipe 10 </ b> A through the swivel joint 17 in a rotatable state.
[0012]
Here, as described above, the hydraulic hose 10C is fixed to the other end side of the machine body side pipe 10A located above the left and right mounting seat frames 11 and 11 and in the vicinity of the boss cylinder portion 5a of the boom base end portion. It is interposed between one end side of the front side pipe 10B, and thus is located between the left and right mounting seat frames 11 in a plan view. Furthermore, in the present embodiment, the four hydraulic hoses 10C for arm cylinder supply / discharge and bucket cylinder supply / discharge are divided into right and left, and the left and right inner seat frames 11, 11 It is arranged along the side. In this case, the swivel joint 17 is assembled so that the second joint 17B (side to which the hydraulic hose 10C is connected) is positioned on the outer side in the left-right direction of the first joint 17A (side to which the machine body side pipe 10A is connected). Thus, the hydraulic hose 10 </ b> C can be easily arranged along the left and right inner side surfaces of the left and right mounting seat frames 11, 11.
[0013]
When the boom 5 is moving downward, the hydraulic hose 10C is positioned above the left and right mounting seat frames 11 and 11 and is substantially linear (see FIGS. 3 to 6). When the boom 5 is swung upward from this state, the central portion of the hydraulic hose 10C bends downward as the boom 5 moves upward, and the bent portion is a space between the left and right mounting seat frames 11, 11. (See FIGS. 7 to 10). In this case, since the fuselage-side pipe 10A and the hydraulic hose 10C are connected via the swivel joint 17, the hydraulic hose 10C freely rotates with respect to the fuselage-side pipe 10A at the connecting portion, thereby the hydraulic hose 10C. When the angle is bent, both end portions of the hydraulic hose 10C are hardly bent, and it is possible to avoid stress concentration on both end portions of the hydraulic hose 10C.
[0014]
In the configuration as described above, a front hydraulic pipe 10 serving as a pressure oil supply / discharge flow path to the arm cylinder 8 and bucket cylinder 9 provided in the front 4 is connected to a control valve 15 mounted on the machine body side. Machine body side pipe 10A, front side pipe 10B fixed to the base end of boom 5, and flexible hydraulic hose interposed between these body side pipe 10A and front side pipe 10B The machine body side pipe 10 </ b> A and the hydraulic hose 10 </ b> C are connected via a swivel joint 17. When the front 4 swings up and down, the hydraulic hose 10C extends and bends and deforms. However, the bent portion of the hydraulic hose 10C is free to swing the base end of the boom 5. The hydraulic hose 10C is deformed while freely rotating with respect to the fuselage side pipe 10A while being positioned in a space between the left and right mounting seat frames 11, 11 that are pivotally supported.
[0015]
As a result, when the hydraulic hose 10C expands or bends and deforms as the front 4 moves up and down, a part of the hydraulic hose 10C, for example, a portion in the vicinity of the connection portion with the machine body side pipe 10A or the front side pipe 10B. Thus, the stress does not concentrate and the portion does not deteriorate at an early stage, which can greatly contribute to the improvement of the durability of the hydraulic hose 10C. In addition, the swivel joint 17 for rotatably connecting the hydraulic hose 10C and the fuselage side pipe 10A does not need to be provided coaxially with the support shaft 12 that pivotally supports the boom 5 so that the swivel joint is supported. There is no problem that the support shaft must be divided into two parts in order to be coaxial with the shaft.
[0016]
Further, when the hydraulic hose 10C is bent, the bent portion is located in the space between the left and right mounting seat frames 11, 11, so that the bent portion is placed on the other portion of the hydraulic excavator 1. There is no possibility of interference, and the hydraulic hose 10C can be effectively protected. In addition, the hydraulic hose 10C is arranged so as to be substantially along the left and right inner side surfaces of the left and right mounting seat frames 11, 11, so that the swing motor 14 is arranged between the left and right mounting seat frames 11, 11. Even if this is done, the bent portion of the hydraulic hose 10 </ b> C can be positioned between the left and right mounting seat frames 11, 11 without interfering with the turning motor 14.
[0017]
Of course, the present invention is not limited to the above-described embodiment. In the above-described embodiment, the swivel joint is arranged at the connection portion between the hydraulic hose and the fuselage-side piping. It may be arranged at the connection part of the two or both of the connection parts.
[Brief description of the drawings]
FIG. 1 is a side view of a hydraulic excavator.
FIG. 2 is a plan view of a hydraulic excavator.
FIG. 3 is a plan view of a main part in a boom lowering state.
FIG. 4 is a side view of a main part in a boom lowering state.
FIG. 5 is a main part rear view in a boom lowering state.
FIG. 6 is a perspective view of a main part in a boom lowering state.
FIG. 7 is a plan view of a main part in a boom moving state.
FIG. 8 is a main part rear view in a boom upward movement state.
FIG. 9 is a perspective view of a main part in a boom upward movement state.
FIG. 10 is a perspective view of a main part in a boom upward movement state.
[Explanation of symbols]
4 Front 5 Boom 6 Arm 7 Bucket 8 Arm cylinder 9 Bucket cylinder 10 Hydraulic piping 10A Machine side piping 10B Front side piping 10C Hydraulic hose 11 Mounting seat frame 12 Support shaft 15 Control valve 17 Swivel joint

Claims (1)

In a construction machine in which a base end portion of a front provided with a hydraulic actuator is pivotally supported by left and right mounting seat frames projecting from the machine body so as to be swingable up and down, the hydraulic actuator is provided from a hydraulic device provided on the machine body side. The hydraulic piping that becomes the pressure oil flow path to the airframe is interposed between the fuselage side piping fixed to the fuselage side, the front piping fixed to the front side, and between the fuselage side piping and the front piping. In constructing using a flexible hydraulic hose, the left and right mounting seat frames in plan view of the part connected to the hydraulic hose of the airframe side piping and the part connected to the hydraulic hose of the front side piping by arranging so as to be positioned between the, together with the hydraulic hoses to be positioned between the left and right mounting seat frame in a plan view, and a hydraulic hose and the inboard pipeline or front pipe Connected via a swivel joint located between the right mounting seat frame, hydraulic hoses in a state where the front is moved downward becomes substantially linearly located above between the left and right mounting seat frame, When the front is moving up, the central part of the hydraulic hose bends downward, and the bent part is in the space between the left and right mounting seat frames, so that both ends of the hydraulic hose can be bent almost. A piping structure in a construction machine, characterized in that it is configured so as not to exist .

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