KR20030003192A - Apparatus for driving drain-board of crane for reinforcing ground of weakness - Google Patents

Abstract

PURPOSE: A drain board press fitting apparatus of a crane for improving weak foundation is provided to simplify the overall structure of the press fitting apparatus and make the rise and fall operation of a press fit casing carried out more easily and safely. CONSTITUTION: A rising wire(26) is connected to the upper side of a wire clamping plate(28) via a first tension roller at the upper part of a wire drum(21) and an upper roller(24) of the uppermost end of a boom rest(12), being wound to a take-up surface(21a) at one side of the wire drum(21). A falling wire(27) is connected to the lower side of the wire clamping plate(28) via a second tension roller at the upper part of the wire drum(21), a space maintaining roller(23) at the lower part of the wire drum(21) and a lower roller(25) of the lowermost end of the boom rest(12).

Description

Apparatus for driving drain-board of crane for reinforcing ground of weakness}

The present invention relates to a drain board press-fitting device for a soft ground improvement crane used to press-fit various drain boards for discharging underground pore water of the soft ground onto the soft ground. More specifically, the casing for drain board press-fitting is provided. It is possible to raise and lower by the wire drum of the wire, the wire fixing plate to which the lifting wire is connected to install the guide roller in contact with the guide housing of the press-fit casing, elastic contact with the upper and lower sides of the wire fixing plate at the upper end and the lower end of the boom By installing the cushioning means, the overall structure of the press-fitting device can be easily and safely carried out while simplifying the overall structure of the press-fitting device. Rather, breakage of the press-fit device The present invention relates to a drain board press-fitting device for a soft ground improvement crane to minimize the phase.

In general, the areas formed by reclamation, dredging, or reclamation of coasts, rivers, lakes, and harbors not only form wetlands mixed with water and viscous soils or water, but also contain void water in the ground. Therefore, since the overall strength of the ground becomes very weak, a soft ground is formed. In order to use such an area as an industrial area or a commercial area, the work of improving the soft ground to be suitable for the site utilization must be preceded.

As described above, in the method for improving the soft ground, a sand pillar or a drain paper board is pressed into the ground by a casing, such as a sand drain method or a paper darin method. Vertical drainage method to promote consolidation of the soft ground by discharging it to the ground, and sand compaction pile to reinforce the bearing capacity along with the discharge of underground gap water by forming sand compaction pile on the ground. Various methods such as construction method, forced replacement method by Santo landfill, or lime column method using lime pillar are variously adopted depending on the site conditions. The vertical drainage method described above is very widely used.

The soft ground improvement crane used in the vertical drainage method as described above is fixed to the boom stand vertically by a wire rope vertically in front of the crane vehicle, the drain board for discharging the ground gap water in the front inside the boom The inserted press-fit casing is installed to be moved up and down along the guide housing fixed to the boom, and the lifting wire is connected to the upper and lower sides of the wire fixing plate which is formed integrally with the press-fit casing and exposed to the rear of the guide housing. Lifting wire is made of a configuration connected to each wire drum rotatably installed on the boom target by a drive motor having a reducer.

Accordingly, the wire drum connected to the descending wire and the wire drum connected to the lifting wire are rotated in one direction to press the casing for press fitting into the soft ground together with the drain board, and then rotate each wire drum in the opposite direction for press fitting. When only the casing is separated from the soft ground, only the drain board can be easily inserted on the soft ground, and the drain board inserted in this way absorbs the groundwater in the soft ground and discharges it to the ground surface.

However, in the conventional drainboard press-fitting device installed in the above-mentioned soft ground improvement crane, since two wire drums for winding up and down the wires for lifting and lowering wires are separately installed, a drive motor for rotating the wire drums. And a tension roller for sequentially winding the reducer and the lifting wire to the corresponding wire drum, there was a problem in that the overall structure of the drain board press-fitting device was somewhat complicated because it was to be installed for each wire drum.

In addition, in order to move up and down the press-in casing, each wire drum connected with the up-and-down wire must be rotated at the same time. In addition to the movement process of the press-in casing, the press-in casing is pressed into the soft ground and pressed from the soft ground. If the tension applied to the elevating wire (ie, the rotational speed of each wire drum) cannot be properly adjusted when the casing is pulled out, the wire of any one of the elevating wires remains loose and the wire is There is a problem that it is difficult for the worker on the crane vehicle to smoothly lift and lower the operation of the press-fit casing, such as is not staggered sequentially.

And, the guide housing which serves as a moving passage of the press-fit casing is fixedly installed along the front inner surface of the boom extending to a somewhat higher position, because the press-fit casing itself is simply suspended by the lifting wire, When the boom or the wire is shaken due to various causes such as wind during the movement of the press-fit casing, a collision between the press-fit casing and the guide housing frequently occurs and the press-fit casing and the guide housing are easily damaged. According to the shaking of the press-fit casing, when the lifting wire is not wound properly on the wire drum and is staggered or severely, there is a problem that the wire is separated from the wire drum or the roller.

In particular, when a worker in a crane vehicle does not accurately grasp the position of the press-fit casing and moves the press-fit casing to the top or bottom of the boom, the wire fixing plate is formed integrally with the press-fit casing and is exposed to the inside of the boom. It is caught by strong collision with the upper roller installed at the top of the boom or the lower roller installed at the bottom of the boom.The operator who rides the crane vehicle can quickly grasp such a situation and stop the operation of the press-fitting device. There was a problem causing breakage of the roller and the wire and the press-fit casing.

The present invention has been made to solve the conventional problems as described above, the drain board press-fitting device of the soft ground improvement crane according to the present invention is to be able to raise and lower the drain board press-fit casing in one wire drum, The wire fixing plate to which the elevating wire is connected is provided with a guide roller which is in contact with the guide housing of the press fitting casing, and the upper and lower portions of the boom are provided with a cushioning means for elastic contact with the upper and lower sides of the wire fixing plate, so that the overall structure of the pressing device While simplifying the operation, the lifting and lowering operation of the press-fit casing can be carried out more easily and safely.In addition to the various shocks and cross-linking and detachment phenomenon of the press-fitting casing, the damage of the press-fitting device caused by this can be achieved. The technique of the present invention to minimize the It is an enemy task.

The present invention for achieving the above technical problem, the boom is vertically fixed to the front of the crane vehicle, the pressurized casing of the drain board is installed in the boom can be lowered along the guide housing, the press-in The casing is formed integrally with the wire fixing plate connected to the elevating wire, the elevating wire is connected to the wire drum rotatably installed on the boom object, the elevating wire is wound on one side of the winding side of the wire drum It is connected to the upper side of the wire fixing plate via the first tension roller of the upper portion of the wire drum and the upper roller of the boom stand in the state, the lower wire is the second tension roller of the upper portion of the wire drum in the state of being wound on the other winding surface of the wire drum To the lower side of wire fixing plate through gap keeping roller at lower part of wire drum and lower roller at bottom of boom And the lifting wires wound on both sides of the winding surface of the wire drum are wound so that the winding directions thereof are opposite to each other. The wire fixing plate contacts the outer wall surfaces of both sides of the guide housing to provide a press-fit casing. Guide rollers for guiding the lifting and lowering are rotatably installed, and a pair of cushioning means in elastic contact with the wire fixing plate by the elastic force of the coil spring is provided on the bracket below the upper roller and the lower roller of the boom. It is characterized by being installed.

1 is a side view showing a soft ground improvement crane equipped with a drain board indentation apparatus according to the present invention.

Figure 2 is a schematic device diagram showing a wire connection structure of the drain board press-fit apparatus according to the present invention.

Figure 3 is an enlarged front view showing a wire connection structure of the drain board press-fit apparatus according to the present invention.

Figure 4 is a plan sectional view showing the casing lifting structure of the drain board press-fit apparatus according to the present invention.

Figure 5 is a front sectional view showing the casing lifting structure and the buffer means of the drain board press-fit apparatus according to the present invention.

6 (a) and 6 (b) are side cross-sectional views showing the working relationship of the cushioning means.

<Explanation of symbols for main parts of drawing>

10 crane vehicle 11: caterpillar 12: boom

13: wire rope 14, 15: wire rope fixture 16: hydraulic jack

17: drive motor 17a: reducer 18: rotary support plate

20: press-fit device 21: wire drum 21a: winding surface

22: tension roller 22a: first tension roller 22b: second tension roller

23: space keeping roller 24: upper roller 25: lower roller

26: lifting wire 27: falling wire 28: wire fixing plate

28a: casing connection 29: press-fit casing 30: drain board

31: guide housing 32: fixed plate 33: guide roller

40: buffer means 41: bracket 42: support

43: head portion 43a: buffer surface 44: coil spring

45: spring support 46: nut

Hereinafter, described in detail with reference to the accompanying drawings, the present invention for achieving the above object is as follows.

1 is a side view showing a soft ground improvement crane equipped with a drain board indentation apparatus according to the present invention, Figure 2 is a schematic device diagram showing a wire connection structure of the drain board indentation apparatus according to the present invention, Figure 3 An enlarged front view of the wire connection structure of the drain board press-fitting device according to the present invention, in the description of the reference numerals, reference numeral 22c denotes a roller shaft, and 24a and 25a denote a roller buffer.

4 is a plan sectional view showing the casing lifting structure of the drain board press-fitting apparatus according to the present invention, and FIG. 5 is a front sectional view showing the casing lift-up structure and the shock absorbing means of the drainboard press-fitting apparatus according to the present invention. (A) and (B) are side cross-sectional views showing the working relationship of the cushioning means, and reference numeral 47 in the description of the reference numerals denotes the washer.

First, the overall configuration of the soft ground improvement crane is installed in the drain board indentation apparatus according to the present invention, as shown in Figure 1, the lower end of the crane vehicle 10, the endless track for the movement of the crane vehicle 10 (11) is installed, the front of the crane vehicle 10 is fixed to the boom stand 12 of a predetermined height perpendicular to the ground by a wire rope 13, the front lower side of the boom 12 and the crane vehicle ( On the rear side of 10), wire rope fasteners 14 and 15 for connecting and fixing the wire rope 13 are installed, and the crane vehicle 10 is grounded when the drain board is pressed in front and rear of the crane vehicle 10. The hydraulic jack 16 for firmly supporting against is provided to be able to raise and lower.

In addition, the drain board press-fitting apparatus according to the present invention is installed inside the boom stand 12 and is lifted by the wire drum 21 and the rollers 22 to 25 that are rotatably supported on the boom stand 12. Centering on the connecting structure of the lowering wires 26 and 27, the press-up and lowering structure of the press-fitting casing inserted through the guide housing 31 inside the boom stand 12 and the upper end and the lower end of the boom 12 are press-fitted. It is made of a buffer means 40 which is in elastic contact with the wire fixing plate 28 of the casing for, this will be described in more detail for each structure with reference to Figures 2 to 6 as follows.

First, the installation structure of the wire drum 21 and the rollers 22 to 25 and the connection structure of the lifting wires 26 and 27 through the wire drum 21 and the rollers 22 to 25 are shown in FIGS. As shown in FIG. 3, a wire drum 21 is rotatably installed at a lower portion of the boom 12, and a first tension roller 22a and a second tension roller are disposed on an upper portion of the wire drum 21. A pair of tension rollers 22 made of 22b are rotatably installed, and an upper roller 24 and a lower roller 25 are rotatably installed at upper and lower ends of the boom 12, respectively. A space keeping roller 23 is rotatably installed between the wire drum 21 and the lower roller 25.

In addition, the lifting wire 26 connected to the wire fixing plate 28 of the press-fit casing 29 from the wire drum 21 is wound on the one winding surface 21a of the wire drum 21. 21) It extends toward the upper side of the first tension roller 22a, is wound around the tension roller 22a once, and then extends to the upper roller 24 side of the upper end of the boom 12, and thus to the upper roller 24 side. The extended lifting wire 26 extends downward along the boom 12 in a state spanning the upper roller 24 and is connected to the upper center portion of the wire fixing plate 28.

Further, the lower wire 27 connected to the wire fixing plate 28 of the press-fit casing 29 from the wire drum 21 is wound on the other winding surface 21a of the wire drum 21 in a state in which the wire drum ( The lower wire 27 extending toward the second tension roller 22b of the upper part 21 and extending back to the wire drum 21 in a state spanning the tension roller 22b, and thus extending to the wire drum 21 side. Is extended to the top along the boom 12 in a state spanning the gap holding roller 23 and the lower roller 25 is made of a structure connected to the lower central portion of the wire fixing plate 28.

The wire drum 21 is a driving motor fixed together with the reducer 17a on both sides of the boom 12 in a state where the wire drum 21 is inserted to be supported by the rotation support plates 18 fixed to both sides of the boom 12. Is connected to (17), the winding surface (21a) of the wire drum 21 is a wire winding spiral groove is continuously formed in one direction so as to wind the lifting wire (26, 27), the Lifting wires 26 and lowering wires 27 are respectively wound on both sides of the winding surface 21a.

The lifting wire 26 wound on the winding surface 21a is wound from the left side of the wire drum 21 toward the center portion in the drawing, and the lowering wire 27 is in a direction opposite to the direction in which the lifting wire 26 is wound. As the lifting wire 26 is released from the left winding surface 21a as it is wound from the right side of the wire drum 21 to the center in the drawing, the lifting wire 26 is lowered to the winding surface 21a where the lifting wire 26 is released. When the wire 27 is wound and the lowering wire 27 is released from the right winding surface 21a, the lifting wire 26 may be wound around the winding surface 21a where the lowering wire 27 is released. It is.

In addition, the first and second tension rollers 22a and 22b provided on the upper portion of the wire drum 21 give a predetermined tension to the lifting wires 26 and 27 to wind up the wound surface of the wire drum 21 ( The wires 26 and 27 are sequentially wound to 21a), and are rotatably inserted into roller shafts 22c fixed to both sides of the boom 12, and the wire drum 21 And the space maintaining roller 23 installed between the lower roller 25 and the lower wire 25 extending through the second tension roller 22b to the lower roller 25 are in contact with the wire drum 21. As a preventive method, any position on the boom 12 may be provided as long as it does not interfere with the operation of the lower wire 27 moving through the second tension roller 22b and the lower roller 25.

In addition, the upper roller 24 and the lower roller 25, which are installed at the top and bottom ends of the boom 12, are also rotatably installed on roller shafts fixed to both sides of the boom 12, as shown in FIG. As described above, both ends of the roller shafts of the upper roller 24 and the lower roller 25 are vibrated when the lifting and lowering movement of the press-fit casing 29 or when the press-fit casing 29 is pushed in and out of the soft ground. In addition, it is installed in connection with the roller buffer 24a (25a) to absorb the shock, the roller buffer 24a (25a) is to use the hydraulic or spring type suitable to use, as used in the general crane desirable.

For raising and lowering the press-fit casing 29 along the boom 12 by the movement of the lifting wires 26 and 27 according to the operation of the wire drum 21 and the rollers 22 to 25 as described above. As shown in FIGS. 4 and 5, the lifting structure of the press-fit casing 29 has a guide housing 31 extending along the boom 12 on the front inner surface of the boom 12 to the fixed plate 32. The press-fit casing 29 is fixedly mounted on the boom stand 12 and the drain board 30 is inserted into the guide housing 31 to move up and down along the guide housing 31. It is inserted and installed where possible.

The wire fixing plate 28 is integrally formed with the press-fit casing 29 by a casing connecting portion 28a extending through the rear opening of the guide housing 31 at the rear of the press-fit casing 29. Up and down wires 26 and 27 are connected to upper and lower sides of the wire fixing plate 28 so that the press-fit casing 29 is connected to the wire fixing plate 28 by the rotation of the wire drum 21 according to the operation of the driving motor 17. Along with the guide housing 31, the guide rollers 33 may be rotatably installed on the front side of the wire fixing plate 28 to be in contact with both outer walls of the guide housing 31.

The guide roller 33 is intended to guide the lifting and lowering movement of the press-fit casing 29 when the press-fit casing 29 is moved up and down along the guide housing 31, the wire fixing plate ( It is preferable to install a total of four guide rollers 33, one at each corner portion of 28), and a rubber cover or the like is placed on the outer circumferential surface of the guide roller 33 so as to minimize damage to the outer wall of the guide housing 31. Or it is preferable to use the guide roller 33 made of a hard rubber or plastic material itself.

A buffer for elastically supporting the upper and lower sides of the wire fixing plate 28 when the wire fixing plate 28 of the press-fitting casing 29 moving along the casing lifting structure as described above moves to the upper end or the lower end of the boom 12. The means 40 is a pair of brackets 41 fixed inside both sides of the boom 12 at the lower side of the upper roller 24 and the upper portion of the lower roller 25, as shown in FIGS. 5 and 6. And a support 42 having a rear end portion penetrated into the bracket 41 and a head portion 43 having a buffer surface 43a formed at the front end thereof, and a head portion 43 of the support 42. And a coil spring 44 elastically interposed between the bracket 41 and the nut 46 fastened to the rear end of the support 42 penetrating the bracket 41.

In addition, between the coil spring 44 and the bracket 41, a spring support 45 for protecting the lower end of the coil spring 44 is inserted on the support 42 or integrally formed with the support 42. The nut 46 is fastened and installed with two nuts 46 interposed between washers 47 so as not to be released from the support 42 by the elastic force of the coil spring 44, and the support 42 is provided. The shock absorbing surface 43a installed at the head 43 is formed of hard rubber or plastic so as to prevent shock and noise generated when the wire fixing plate 28 collides with the wire fixing plate 28.

Hereinafter, the working relationship of the present invention having the above configuration will be described in detail with reference to the accompanying drawings.

First, in order to press-fit the press-fit casing 29 into which the drain board 30 is inserted into the soft ground, an operator who rides on the crane vehicle 10 operates the drive motor 17 of the wire drum 21 while the wire drum is operated. When the left side 21 is rotated in FIG. 2, the lifting wire 26 wound around the left winding surface 21a of the wire drum 21 is released from the winding surface 21a, and at the same time, the lowering wire 27 is the second wire. The lifting wire 26 is sequentially wound around the winding surface 21a from which the lifting wire 26 is released through the tension roller 22b.

Therefore, the lower wire 27 connected to the lower side of the wire fixing plate 28 via the gap holding roller 23 and the lower roller 25 from the wire drum 21 strongly pulls the indentation casing 29 downward, As a result, the press-fit casing 29 is moved to the lower portion of the boom 12 along the guide housing 31 installed on the boom 12 so that the press-fit casing 29 together with the drain board 30 is soft on the ground. It can be pressed in easily.

As described above, the press-fit casing 29 is press-fitted together with the drain board 30 on the soft ground, and then the operator who rides on the crane vehicle 10 operates the drive motor 17 of the wire drum 21. When the wire drum 21 is turned to the right in FIG. 2, the lower wire 27 wound on the right winding surface 21 a of the wire drum 21 is released from the winding surface 21 a and the lifting wire 26 is The lower wire 27 is sequentially wound around the winding surface 21a from which the descending wire 27 is released through the first tension roller 22a.

Therefore, the lifting wire 26 connected to the upper side of the wire fixing plate 28 from the wire drum 21 via the upper roller 24 strongly pulls the indentation casing 29 upward, thereby press-fitting the soft ground. The casing 29 moves upward along the guide housing 31 installed on the boom 12. In this process, viscous soil or mud in the soft ground is absorbed by the drain board 30, and the drain board 30 ), So that the drain board 30 is kept embedded in the ground and only the indentation casing 29 is pulled out of the soft ground.

As described above, the elevating wires 26 and 27 are loosened during the elevating operation of the press fitting casing 29 by the wire drum 21 and the rollers 22 to 25 and the elevating wires 26 and 27. It is always maintained at a constant tension, because the lifting wires 26, 27 are rotated in the first state in which the wire drum 21 is wound to maintain a constant tension on the same wire drum 21. As the elevating wires 26 and 27 are released or wound at the same speed from the wire drum 21, the elevating wires 26 and 27 are tensioned in the elevating wires 26 and 27 during the elevating operation of the press-fit casing 29. This is because the difference rarely occurs.

As described above, the elevating wires 26 and 27 are alternately wound or unwound on one wire drum 21 so that only one wire drum 21 is rotated to raise and lower the casing 29 for press-fitting. Not only can the operation of the elevating wire 26 and the lowering wire 27 for movement be performed at the same time, but also the tension of the elevating wire 26 and the lowering wire 27 when the lowering movement of the press-fit casing 29 is always performed. By keeping constant, the lifting wires 26 and 27 can be wound on the winding surface 21a of the wire drum 21 in a sequential and safe manner, thereby allowing the operator who rides on the crane vehicle 10 to drain. It is possible to perform the press-in operation of the board 30 more easily and efficiently.

In addition, as shown in FIGS. 4 and 5, the guide roller 33 installed on the wire fixing plate 28 is the press-fit casing 29 during the press-fit casing 29 moves along the guide housing 31. ) Can be safely supported without shaking, even if the boom 12 or the lifting wires 26, 27 are shaken due to wind or various causes, the press-fit casing 29 and the guide housing 31 and The collision of the does not occur at all, thereby minimizing damage to the press-fit casing 29 and the guide housing 31, as well as the lifting and lowering wire (26) (27) due to the swing of the press-fit casing (29) ) Staggering or deviation can be minimized.

In particular, the operator who rides on the crane vehicle 10 does not accurately grasp the position of the press-fit casing 29 and moves the wire fixing plate 28 of the press-fit casing 29 to the upper end or lower end of the boom 12. However, as shown in FIG. 6A, a pair of shock absorbing means 40 installed on the lower side of the upper roller 24 and the upper side of the lower roller 25 collide with the wire fixing plate 28 primarily. By the elastic force of the buffer surface 43a and the coil spring 44 formed on the head portion 43 of the support 42, the shock caused by the wire fixing plate 28 can be absorbed primarily, thereby the wire fixing plate ( It is possible to prevent the damage of the press-fit device caused by the 28 directly collide with the upper roller 24 or the lower roller 25.

In addition, even if the operator boarded on the crane vehicle 10 can quickly grasp such a situation and do not stop the operation of the press-fitting device quickly, as shown in (b) of FIG. 6, the support 42 of the shock absorbing means 40 is shown. Since the coil spring 44 is pushed backward while compressing the coil spring 44, the elastic force of the compressed coil spring 44 supports the tension of the lifting wires 26 and 27 to support the roller 24 by the wire fixing plate 28. It is to be possible to minimize the damage of the 25 or the wires 26 and 27 and the press-fit casing 29.

As described above, the drain board press-fitting apparatus of the soft ground improvement crane according to the present invention can not only simultaneously perform the operation of the wire for the lifting and lowering movement of the press-fitting casing by rotating one wire drum, Each wire is always maintained at a constant tension so that the wire can be wound around the wire drum in a sequential and safe manner, thereby allowing the operator in the crane vehicle to more easily and efficiently press-fit the drain board. Will be.

In addition, since the guide roller installed on the wire fixing plate can safely support the movement of the press-fit casing without shaking, it is possible to prevent the collision between the press-fit casing and the guide housing generated when the boom or the wire is shaken due to wind or various causes. There is an effect, thereby minimizing damage to the press-fit casing and the guide housing, and also prevents the wires staggered or detached phenomenon due to the swing of the press-fit casing.

In particular, even if a worker in a crane vehicle does not accurately grasp the position of the press-fit casing and moves the wire fixing plate of the press-fit casing to the upper end or the lower end of the boom, the shock absorbing means having the coil spring elastically supports the wire retaining plate. Therefore, there is an effect that can prevent the damage or breakage of the press-fit device caused by the wire fixing plate directly collides with the upper roller or the lower roller.

Claims (3)

In front of the crane vehicle 10, the boom 12 is fixedly installed vertically by the wire rope 13, and the press-in casing 29 in which the drain board 30 is inserted is installed inside the front of the boom 12. It is installed to move up and down along the guide housing 31 fixed to the boom 12, and is formed integrally with the press-fit casing 29, the wire fixing plate 28 exposed to the rear of the guide housing 31 is raised Lower wires 26 and 27 are connected, and the lifting wires 26 and 27 are rotatably mounted on the boom 12 by a drive motor 17 having a reducer 17a. In connection with (21), The lifting wire 26 is wound on one side of the winding surface 21a of the wire drum 21, and the first roller 22a on the upper side of the wire drum 21 and the upper roller 24 on the upper end of the boom 12. Connected to the upper side of the wire fixing plate 28 through the, The descending wire 27 is wound around the other winding surface 21a of the wire drum 21, and the space between the second tension roller 22b of the upper part of the wire drum 21 and the lowering roller of the wire drum 21 23) and the lower roller 25 at the bottom of the boom stand 12 are connected to the lower side of the wire fixing plate 28, The lifting wire 26 and the lowering wire 27 wound on both sides of the winding surface 21a of the wire drum 21 are wound so that their winding directions are opposite to each other. Board Indenter. According to claim 1, The wire fixing plate 28 is provided with a rotatable guide roller 33 which is in contact with the outer wall surface of both sides of the guide housing 31 to guide the lifting and lowering movement of the press-fit casing 29 Drain board press-fitting device of the crane for soft ground improvement. According to claim 1 or claim 2, The upper roller 24 of the boom 12 and the lower roller 25 of the upper side of the pair of shock absorbing means 40 in elastic contact with the wire fixing plate 28 is a boom ( 12) is installed on the bracket 41 fixed to, The buffer means 40 has a support 42 having a head portion 43 having a rear end portion penetrated through the bracket 41 and a buffer surface 43a formed at the front end thereof, and a head portion of the support 42. A coil spring 44 elastically interposed between the 43 and the bracket 41, and a nut 46 fastened to the rear end of the support 42 through the bracket 41, characterized in that the Drain board press-fitting device for crane for soft ground improvement.