KR20120060008A

KR20120060008A - Counterweight mounting/separating apparatus for construction machinery

Info

Publication number: KR20120060008A
Application number: KR1020100121556A
Authority: KR
Inventors: 박병화
Original assignee: 두산인프라코어 주식회사
Priority date: 2010-12-01
Filing date: 2010-12-01
Publication date: 2012-06-11

Abstract

The present invention relates to a counterweight mounting / detaching device for a construction machine, and in particular, facilitates the installation / removal of the counterweight, and lifts the counterweight and places it in a mounting position to prevent interference such as contact with the vehicle body (frame) of the construction machine. The present invention relates to a counterweight demounting device having a structure capable of preventing a small hydraulic cylinder having fewer strokes for the same rotation angle of a link, and for this purpose, a driven part and a driving part disposed to face each other about a rotation point. A link having a linkage, a hydraulic cylinder connected to the driving portion of the link to rotate the link, and a flexible body disposed at one end of the link follower and having one end fixed to the rear frame and the counterweight fastened to the other end. In addition, the follower of the link is bent at a portion adjacent to the pivot point It further includes a formed bent portion, when mounting / removing the counterweight through this structure, prevents interference between the counterweight and the vehicle body (rear frame), and rotates the link using a small hydraulic cylinder having fewer strokes This reduces the load on the hydraulic pump and can alleviate the height constraints on the mounting position.

Description

Counterweight mounting / separating apparatus for construction machinery

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a counterweight demounting device for a construction machine, and more particularly, a counter for a construction machine that can separate or mount a counterweight through a combination of a hydraulic cylinder and a link mechanism at the rear of a main body of a construction machine such as an excavator, a loader, a forklift, or the like. It is related with a weight removal apparatus.

In general, excavators perform a variety of tasks, such as excavation, leveling, ground compaction, lifting of heavy objects, and the like. An excavator is a work machine consisting of a boom, an arm and a bucket, and an operation of the excavator is performed by controlling a work machine such as a boom, an arm and a bucket through a driving means such as a hydraulic cylinder.

The loader is an excavation work for excavating soil and sand at the construction site, a transport work for carrying the excavated soil, a loading and unloading work for loading or unloading the transported soil on a freight vehicle, road stop work, snow removal work, and towing work. It is widely used to perform such. Such a loader has a structure provided with a boom which is installed at the front side of the vehicle and operated by a boom cylinder, and a bucket which is rotatably installed at the tip of the boom and operated by a bucket cylinder.

A forklift is a kind of industrial vehicle that can lift or lower loads of heavy weights, and is used to move heavy loads at a short distance or to load or unload such loads into various transport vehicles. The forklift truck consists of a main body including an engine and a mast assembly provided on the front side of the main body. The mast assembly is provided with a carriage having a fork, and may be composed of two stages, three stages, etc. in consideration of the moving height of the heavy material.

Construction machines such as excavators, loaders, or forklifts as described above are counterweights that act to balance the weight of the body or external forces acting on the body, i.e. counterweight load counters to counteract the moment due to the load. (counterweight).

These counterweights are usually cast-type manufactured by casting or structural type manufactured by cutting and welding of a steel plate structure, and as described above, a considerable weight is required to balance the weight or external force of the construction machine body. It is generally configured to have

In addition, the counterweight results in an increase in the body weight of the construction machine, which may cause unnecessary constraints due to the weight of the counterweight when the construction machine is not in operation such as when moving on a road. Thus, the counterweight is typically moved to the work site separately from the construction machine, mounted on the construction machine at the work site, and then separated again after the work.

1A and 1B are schematic diagrams showing an example of a counterweight detachment apparatus of the related art. 1A and 1B, the counterweight detachable device 10 according to the related art is rotatably coupled to a proximal end through a bracket 24 to a fixed plate 22 formed on a main body rear side 20 and a roller 32 at a distal end. Relief link (30) is formed and the rotatable cylinder (40) rotatably coupled via the bracket 26, one end is rotatably coupled to the front end of the relief link 30 to rotate the relief link (30) And a rope 42 having one end fixed to the fixing plate 22 and the other end fastened to the counterweight 12 via the roller 32. It further includes a lifting cylinder 34 which is stretched at one point of the relief link 30 to adjust the relative position of the roller 32.

The counterweight demounting device 10 of this structure provides a structure in which the counterweight can be mounted / detached through the coupling structure of the rope 42 and the relief link 30 and the relief cylinder 40 which rotates the relief link. In order to avoid interference such as contact with the main body rear part when mounting / removing the counterweight, a lifting cylinder 34 for adjusting the relative position of the roller 32 is required. Further, since one end of the relief cylinder 40 causing the rotation of the relief link 30 is fastened to the tip end of the relief link 30, that is, the vicinity of the roller 32, the rotation radius (range) of the relief link is greatly increased. In order to solve this problem, the stroke range of the relief cylinder 40 has to be increased.

In addition, Figure 2 is a schematic diagram showing another example of the conventional counterweight detachment apparatus. According to FIG. 2, the counterweight detachable device 50 according to the related art includes a first link 72 rotatably fixed to a first bracket 62 and a second bracket (not shown) formed in the main body frame 60. , The second link 74, and the hydraulic pressure that is rotatably fastened to the tip portions of the guide link 76, the first bracket 62 and the first link 72, respectively, connecting the tip portions of the first link and the second link. And a yoke 78 having an upper side fastened to the cylinder 80 and a guide link 76 and a lower side to which the counterweight can be fastened.

The counterweight demounting device 50 of this structure consists of a combination of a link structure 70 composed of a plurality of links 72, 74, 76 and a hydraulic cylinder 80 for rotating the link structure 70. Multiple links, such as links 72, second links 74, and guide links 76, require complex structures that must be joined using multiple brackets 62 and multiple securing pins. Further, since the hydraulic cylinder for rotating the link structure 70 is fastened to the front end of the link structure 70, specifically, the fixing pin to which the first link 72 and the guide link 76 are fixed, As in the case of FIG. 1, in order to increase the turning radius (range) of the link structure 70, the stroke range of the hydraulic cylinder has to be increased.

As described above, the conventional counterweight detachment structure can adjust the relative position of the roller relative to the link up and down in order to avoid the counterweight contacting the vehicle body of the construction machine when the heavy weight counterweight is mounted. There is a need for a complicated configuration such as providing a lifting cylinder which is provided separately or constituting a composite link structure consisting of a first link, a second link, and a guide link. Further, in order to increase the turning radius (range) of the link or composite link structure, there is a constraint that the stroke range of the hydraulic cylinder connected thereto must also be increased.

An object of the present invention is to provide a counterweight detachable device that can avoid the interference of the counterweight and the construction machine body when the counterweight is mounted.

Another object of the present invention is to provide a counterweight detachable device that can be configured by using a simple structure consisting of a link mechanism and a hydraulic cylinder.

Still another object of the present invention is to provide a counterweight detachable device in which a smaller hydraulic cylinder can be used by reducing the stroke range of the hydraulic cylinder.

In order to achieve this object, the present invention is a counterweight mounting and detaching device for transporting and mounting / dismounting the counterweight between a mounting position on a rear frame of a construction machine and a separating position separated from the construction machine, the rotation is fixed to the rear frame A link having a driven part and a driving part disposed to face each other with respect to a point; A hydraulic cylinder including a piston rod fastened to an end of the drive unit and a cylinder tube fastened to the rear frame, the hydraulic cylinder rotating the link around the pivot point; A roller installed in the follower; And a flexible body having a fixed end fixed to the rear frame and both ends of the fastening end to which the counterweight can be fastened, the flexible body having a predetermined length supported by the roller at one point between the both ends. Is provided so that the pivot point is projected further rearward than the roller, and the driven part has a bent portion formed to be bent so as to project forward from an area adjacent to the pivot point.

In the present invention, the point of the rear frame to which the fixed end of the flexible body is fastened is characterized in that it is located in the front / bottom with respect to the pivot point.

Further, in the present invention, the drive unit of the link is characterized in that it is formed with a length shorter than the distance from the rear frame to the pivot point.

In the present invention, the flexible body further includes a length adjusting means capable of adjusting the length of the flexible body.

According to the present invention, when the counterweight is mounted, it is possible to avoid the interference between the counterweight and the construction machine body, and can be configured using a simple structure composed of a link mechanism (assembly of a link and a flexible body) and a hydraulic cylinder. And smaller hydraulic cylinders can be used by reducing the stroke range of the hydraulic cylinders.

1A and 1B are schematic views showing an example of a counterweight demounting apparatus according to the prior art;
2 is a schematic view showing another example of a counterweight detachment apparatus of the prior art;
3 is a schematic perspective view showing a counterweight demounting apparatus according to an embodiment of the present invention;
4A and 4B are schematic views showing the counterweight detachment apparatus of FIG. 3;
5A and 5B are schematic diagrams illustrating the principle of operation around a link and a flexible body in accordance with aspects of the present invention; And
6 is a schematic view showing a counterweight demounting apparatus according to another embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. For reference, the terms "front" and "rear" as used herein refer to directions toward the front and the rear with respect to the vehicle body of the construction machine, respectively.

3 is a perspective view schematically showing a counterweight detachment apparatus according to an embodiment of the present invention, FIG. 4A is a schematic view showing a state in which the apparatus of FIG. 3 is in a mounting position, and FIG. 4B is an apparatus of FIG. It is a schematic diagram which shows the state in a separation position. Referring to Figures 3 to 4b, the counterweight demounting apparatus 100 according to the present invention will be described.

The counterweight demounting device 100 of FIGS. 3 and 4A and 4B transfers and mounts the counterweight (not shown) between the mounting position on the rear frame 102 of the construction machine and the separating position separated from the construction machine. And a device for separating / dividing the link 120 into a pivot 120, a hydraulic cylinder 110 for rotating the link 120, and a distal end of the link 120. One point is supported by the roller 130 and includes a flexible body 140 to which the actual counterweight is fastened.

More specifically, first, the link 120 is a pivot point 122 that is pivotally fixed between a pair of brackets 106 formed on the rear wall 104 of the rear frame 102 via a pivot axis. And the long-length driven part 124 and the short-length driving part 126 which mutually oppose each other centering on the rotation point 122 are formed integrally. As shown in FIG. 3, the links 120 are coupled to the inside of the pair of brackets 106 and are constituted by a pair of links having the same structure as each other, and connect each pivot point 122. On the basis of the coaxial, it is driven together via the driving unit 126 connected to each other. In the following description, the structure of the link 120 will be described based on one link. In addition, the driven portion 124 of the link 120 of the present invention is formed with a bent portion 128 bent to protrude forward in the region adjacent to the pivot point 122, the link 120 having such a shape is mounted position In which the portion between the end of the follower 124 and the bend 128 is arranged parallel to the rear frame 102, more specifically the corresponding rear wall 104 surface. In addition, a roller 130 is formed at the end of the follower 124, and the flexible body 140 is supported by the roller. In addition, the length of the link 120 driving unit 126 is shorter than the distance from which the pivot point 122 protrudes, and more specifically, when the link 120 rotates based on the pivot point 122. It should be formed within a range not having contact with the rear frame 102.

Next, the flexible body 140 may be implemented by, for example, a chain or a wire, etc., one end 142 is fixed on the rear frame 102 and the roller 130 formed at the follower end of the link 120 The fastening end 144 is disposed downward at the other end thereof, and a counterweight may be fastened to the fastening end 144. Obviously, the flexible body 140 should have a tension of at least enough weight to support the weight of the counterweight. Again, the flexible body 140 is composed of a pair of flexible bodies having the same structure as each other, like the link 120, and acts the same for each link 120. In the following, the description is developed based on one flexible body 140 for one link 120 as well.

Next, the hydraulic cylinder 110 is driven using the hydraulic oil delivered from the hydraulic pump (not shown) of the construction machine, the both ends are fastened and stretched to the rear frame 102 and the drive unit 126 of the link to expand the link. It may rotate based on the pivot point 122.

The arrangement of the hydraulic cylinder 110 can be freely configured within the range in which the link 120 can be rotated, but particularly preferably, when the hydraulic cylinder 110 is extended, the link rotates from the detached position to the mounting position. That is, the counterweight is mounted, and when the hydraulic cylinder 110 is contracted, the link is rotated from the mounting position to the separating position, that is, the counterweight is arranged to be separated. In this embodiment, the cylinder tube 112 of the hydraulic cylinder 110 is pivotally fixed by a pair of brackets 108 whose ends are formed on the rear wall 104 of the rear frame 102. The end of the piston rod 114 of 110 is rotatably fastened to the drive part 126 of the link 120. More specifically, the hydraulic cylinder 110 is the end of the piston rod 114 is connected to the connecting shaft for connecting the drive unit 124 of each link 120 between the pair of links 120, the extension of the piston rod drive By this, the drive unit 124 of the link can be rotated in both directions with respect to the pivot point.

The counterweight demounting apparatus 100 described in this embodiment operates as follows.

As shown in FIG. 4A, in the mounting position with the counterweight mounted, the hydraulic cylinder 110 is retracted to move the piston rod 114 into the cylinder tube 112, thereby driving the link 120. 126 is pulled to rotate clockwise relative to the pivot point 122, and the follower 124 of the opposite link is also rotated clockwise relative to the pivot point 122. The fastening end 144 of the flexible body 140 supported by the roller 130 formed at the end of the follower 124 is moved to the separation position with the rotation of the follower 124.

As shown in FIG. 4B, when the contraction of the hydraulic cylinder 110 continues and the piston rod 114 is fully contracted, the follower 124 of the link 120 is also referred to the pivot point 122. The counterweight moves to the maximum rotational position in the clockwise direction, and the counterweight fastened to the fastening end 144 is transferred to a separation position placed on the ground or the like.

Conversely, when the counterweight is to be mounted, the counterweight can be transferred to the mounting position by performing the above-described operation in reverse. For example, the hydraulic cylinder 110 is extended so that the piston rod 114 protrudes from the cylinder tube 112, whereby the driving unit 126 of the link 120 fastened to the piston rod 114 is the pivot point 122. The counterweight is rotated in a counterclockwise direction, while the follower 124 and the roller 130 of the link are rotated counterclockwise to lift the counterweight fastened to the fastening end 144 of the flexible body 140. It may be transferred onto the rear frame 102.

The counterweight demounting device has the following characteristics.

First, the link 120 is formed of a long driven part 124 and a short driving part 126 in both directions with respect to the pivot point 122, and then a hydraulic cylinder ( By fastening the piston rod 114 of 110, it is possible to ensure a more efficient moving distance than the drive length (stroke range) of the piston rod. That is, compared with the conventional case in which the hydraulic cylinder is directly fastened to the driven part in which the roller is formed, even if a hydraulic cylinder having a much shorter driving length is used in the structure of the present invention, it is possible to ensure a sufficient movement distance of the counterweight. That is, in spite of using a hydraulic cylinder having a shorter driving length, it is possible to secure the moving distance of the counterweight of longer or the same length (that is, the moving distance of the follower with a roller).

As such, the use of a hydraulic cylinder with a short drive length allows the hydraulic cylinder to be driven with a smaller amount of hydraulic fluid, in addition to simply having a short driving range of the piston rod. This can be a very useful feature in that it can reduce the load on the weighted hydraulic pump.

Next, the link 120 has a bent portion 128 that is bent near the pivot point 122, and also by this bent portion, the portion between the link follower 124 and the bent portion 128 at the mounting position corresponds to the rear side. By being disposed parallel to the frame 102, specifically the rear wall 104 of the rear frame, it is possible to prevent interference between the counterweight and the demounting devices (specifically, links, rollers and hydraulic cylinders, etc.) in that area. . As such, by preventing interference in the area, the counterweight can be mounted closer to the rear frame, which results in a reduction in the rear protrusion range of the counterweight. In addition, the reduction in the range in which the counterweight protrudes to the rear of the construction machine may reduce the problem that the working radius of the construction machine increases.

In addition, the hydraulic cylinder 110 is arranged to lift the counterweight when extending the piston rod, and to lower the counterweight when contracting the piston rod, it can be configured more effectively. This is due to the fact that in a conventional hydraulic cylinder, the piston rod can provide more force when expanding the piston rod than when it is retracted, i.e. in the direction of lifting the counterweight, e.g. the link point from the disconnected position to the mounting position relative to the pivot point. By allowing the piston rod to elongate when it is rotated counterclockwise, it is possible to drive the link with greater force than when the piston rod is retracted.

Thus, in the embodiment of the present invention, the hydraulic cylinder 110 is rotatably fastened to the end of the cylinder tube 112 via the bracket 108 at the top of the rear frame, that is, the top of the rear wall 106, The end of the piston rod 114 is illustrated in a state rotatably fastened to the connecting shaft connecting the end of the drive unit 126. Due to this configuration, in this embodiment of the present invention, when the piston rod 114 is extended, the driving unit 126 is pushed counterclockwise so that the driven part 124 to which the counterweight is fastened is separated in the counterclockwise direction. Position to the mounting position, and when the piston rod 114 is retracted, pulls the drive 126 clockwise to pull the follower 124 of the counter-tightened link clockwise, in the mounting position. Can be lowered to the disconnected position.

Next, the position where the fixed end 142 of the flexible body 140 is fastened is demonstrated. 5A and 5B schematically illustrate the combination of link 120 and flexible body 140. In this figure, the hydraulic cylinder and the driving portion coupled thereto are omitted, and the link 120 has both ends of the follower 124 (that is, the point where the roller 130 is formed) and the pivot point 122 at both ends. The flexible body 140 is depicted by a solid line with a fixed end 142 and an end of the follower 124, ie a fastening end 144 lying vertically down via the roller 130. In addition, the distance from the end of the follower 124 where the roller is formed to the fastening end 144 disposed vertically downward is called a 'fastening end length' and is indicated by using the symbol 'h'.

Referring to FIG. 5A, the end of the follower 122 of the link 120, that is, the roller 130, has a trajectory 132 that rotates in a circle with respect to the pivot point 122. 144) is different from the trajectory. For example, when the position of the link 120 of FIG. 5A is the mounting position, the trajectory of the fastening end 144 from this mounting position is drawn in the form of a parabola including the highest vertex, unlike the trajectory 132 of the roller 130.

Of course, as shown in the figure, the link 120 itself is disposed at the distal end of the follower 124, that is, the roller 130, is tilted forward with respect to the pivot point 122 at the mounting position. A circular trajectory 132 having a vertex can be formed. Further, in addition to the inclined state of the link, the trajectory 146 of the fastening end may be formed in the form of a parabola having a larger displacement in accordance with the variation of the 'fastening end length' which lies vertically downward from the roller 130. have.

For example, as shown in FIG. 5B, the roller 130 and the fastening end 144 in the mounting position have a fastening end length of h1, and the roller 130 'and the fastening end 144' at the beginning of the separating operation adjacent to the mounting position. Is at the fastening end length of h2, and in the final separation position, the roller 130 "and the fastening end 144" have a fastening end length of h3, and have approximate trajectories indicated by reference numerals 132 and 146, respectively. At this time, each fastening end length has a relationship of h3> h1> h2.

When the link and the flexible body rotate with such a trajectory, it can be seen that the fastening end length h is changed based on the reference point 134 of FIG. 5A. That is, until the reference point 134, the fastening end length h2 is shortened to have a shape having the highest peak within a range smaller than the fastening end length h1 of the mounting position, and becomes longer after the reference point 134. It becomes longer in the range larger than the fastening end length h1 of a position, and finally has a fastening end length of h3 in a separation position.

Thus, the trajectory 146 of the fastening end from the mounting position to the disengagement position is parabolic, rising briefly at the beginning of the disengagement operation and then steadily decreasing since the peak. On the contrary, the trajectory 146 of the fastening end from the detached position to the mounting position is vice versa, that is, continuously increasing and then temporarily lowered after passing the highest peak. This results in an initial detachment operation, i.e. the counterweight is mounted after being lifted slightly after being adjacent to the rear frame, or detached after being lifted slightly, thereby preventing interference such as contact between the counterweight and the rear frame. have.

This is due to the position of the fixed end 142 of the flexible body is located forward / lower with respect to the pivot point 122. For example, after passing the reference point 134, as the link rotates, the fastening end length becomes more and more. It is characterized by the fact that, in the end, the height difference between the mounting position and the dismounting position can be maximized. As such, the difference in height between the mounting position and the dismounting position can be seen as an advantage of alleviating the height limitation on the mounting position.

In addition, although the link 120 is shown to rotate to about 4 o'clock based on the drawing in FIG. 5B, this is merely an example, and the present invention is not limited thereto. For example, as described above, the link 120 is centered on the reference point 134 where the line connecting the fixed end 142 of the flexible body and the pivot point 122 of the link meets the track 132 of the roller. If the link rotates clockwise within the range beyond 134, the engagement end length h becomes longer than the mounting position h1. Accordingly, the rotation angle of the link 120 in the direction from the mounting position to the separation position can be freely set under the condition that, for example, the final position of the roller 130 rotates beyond the upper reference point 134.

Next, Figure 6 shows a counterweight demounting apparatus 100 'according to another embodiment of the present invention. The device 100 'of FIG. 6 is basically similar to the device 100 of FIGS. 3-4B, except that only the length adjusting means 148 is further formed on the flexible body 140'.

The length adjusting means 148 may be a conventional adjusting means, the detailed description thereof will be omitted. For reference, in FIG. 6, the length adjusting means 148 is formed adjacent to the fixed end 142 of the flexible body 140 ′, but the present invention is not limited thereto. It will be appreciated that it may be formed in an adjacent location or any portion of the other flexible body 140 '.

By forming the length adjusting means 148, it is possible to temporarily increase or shorten the length of the flexible body as needed temporarily, thereby further easing the height constraints on the mounting position on the construction machine. That is, for a mounting position of a height that cannot be reached through the rotation of the link, if the length of the flexible body is automatically temporarily increased or shortened using this length adjusting means, the counterweight can be mounted or removed from the mounting position. Has the advantage. In addition, prior to fastening the counterweight to the fastening end of the flexible body, the overall length of the flexible body is adjusted in advance in consideration of the height difference between the mounting position and the disengaging position, so that the flexible body of suitable length can be used so as to be suitable for the work. The environment can be implemented in advance.

As described above, the counterweight demounting apparatus of the present invention has the following advantages. For example, a simple structure consisting of a combination of a link mechanism and a hydraulic cylinder and a linkage of the flexible body can provide a device capable of mounting / removing the counterweight. More specifically, it is possible to use compact hydraulic cylinders with fewer links and shorter strokes compared to conventional devices as exemplified above, thus simplifying the manufacturing process of the device and reducing costs. We can plan.

100: counterweight detachable device 102: rear frame
104: rear wall 106, 108: bracket
110: hydraulic cylinder 112: cylinder tube
114: piston rod 120: link
122: pivot point 124: driven part
126: drive unit 128: bend
130, 130 ', 130 ": roller 132: track of roller
140: flexible body 142: fixed end
144, 144 ', 144 ": Fastener 146: Trajectory of fastener
148: length adjusting means h, h1, h2, h3: tightening end length

Claims

As a counterweight demounting apparatus 100 for transferring / mounting / detaching a counterweight between a mounting position on a rear frame 102 of a construction machine and a separating position separated from a construction machine,
A link 120 having a driven part 124 and a driving part 126 disposed to face each other based on a pivot point 122 fixed to the rear frame 102;
A piston rod 114 fastened to an end of the driving unit 126 and a cylinder tube 112 fastened to the rear frame 102, and rotate the link 120 about the pivot point 122. Hydraulic cylinder 110 to make;
A roller 130 installed on the driven part 124; And
A flexible body having a fixed end 142 fixed to the rear frame and both ends of the fastening end 144 to which the counterweight can be fastened, and supported by the roller 130 at one point between the both ends. 140);
In the mounting position, the link 120 is arranged such that the pivot point 122 further protrudes rearward relative to the roller 130, and the follower 124 faces forward from an area adjacent to the pivot point. Counterweight mounting and detachment device for a construction machine, characterized in that it has a bent portion formed to be bent to protrude.

The counterweight mounting device of claim 1, wherein a point of the rear frame to which the fixed end (142) of the flexible body is fastened is located at the front / lower part with respect to the pivot point (122).

The counterweight mounting device of claim 1, wherein the driving part (126) of the link is formed to have a length shorter than a distance from the rear frame to the pivot point (122).

The counterweight mounting and detachment device according to claim 1, wherein the flexible body (140) further comprises length adjusting means (148) for adjusting the length of the flexible body.