JP2001171976A - Jib crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a jib crane capable of being removably erected over the upper part of a concrete structural body. SOLUTION: This jib crane is provided with a portal basement part 2 striding across the upper part of a concrete structural body, and with press-bolts 3 to be attached to both its leg parts forming the portal basement part, which hold and fix the concrete structural body with stiffening plates from both the surfaces by way of spherical bushes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jib crane temporarily installed on a concrete structure.

[0002]

2. Description of the Related Art When constructing a plant or a building, a jib crane is often used temporarily to take in materials. When a jib crane is temporarily installed on a concrete structure, a large number of anchor bolts are temporarily installed on the concrete structure, and the foundation is fixed to the concrete structure using the anchor bolts. In order to counter the moment applied to the jib crane foundation when the materials are suspended, it is necessary to drive the anchor bolts over a wide area, but when the concrete structure is a wall, Is not sufficient in terms of strength, and it is necessary to arrange anchor bolts on its side.

[0003] However, it is difficult to accurately align the foundation with a large number of anchor bolts which are different from each other at 90 ° or 180 ° on the upper surface and both sides, and the temporary work of the jib crane requires a long time and many manual operations. It was an operation that required In addition, since the operation is performed at a high place, the safety is often a problem. In addition, the temporary jib crane is removed after the construction is completed. At that time, it was also difficult to cut many anchor bolts and cure the concrete surface so as not to leave traces.

In general, as a method of attaching and detaching construction equipment easily and temporarily, a method of fixing the object to be fixed with a bolt provided on the base portion using a clamp system as described above is known. In the case, it was questioned whether a concrete surface whose surface was not sufficiently smooth was sandwiched between bolts as a fixing object and the reaction force and frictional force required by the jib crane could be sufficiently obtained, and it was not put to practical use.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a jib crane which can be easily attached to and detached from an upper part of a concrete structure.

[0006]

According to the present invention, a concrete structure is provided on both sides of a portal structure by means of a contact plate via spherical bushes on both legs of the portal structure. It is a jib crane provided with push bolts to pinch and fix.

In general, when a jib crane is temporarily installed above a concrete structure to take in materials, the concrete structure often forms a wall shape and takes in materials in a manner to get over the wall. The base of the jib crane is formed in a gate shape that straddles the concrete wall, and push bolts that push inward are provided on both legs forming the gate shape,
Each push bolt is a jib crane having a backing plate via a spherical bush, pressing the concrete wall surface with the backing plate, and clamping the concrete structure from both sides.

[0008] Instead of directly pressing the concrete wall surface with the push bolt, a pressing plate is provided on each push bolt via a spherical bush, and the concrete wall is pressed by the pressing plate, so that the concrete surface is not necessarily sufficiently smooth. On the other hand, the contact surface of each push bolt adapts, and the bearing force of concrete and the frictional force between the concrete wall and the caul plate can be fully utilized. Therefore, if the tightening torque of the push bolts is properly controlled, the reaction force and the frictional force to be borne by each push bolt can be sufficiently secured.

According to the present invention, it is not necessary to temporarily install an anchor bolt on a concrete structure, so that the installation work and the cutting and curing work at the time of removal become unnecessary.
The work of fitting the jib crane base to the anchor bolts, which also requires long hours of work to match the 90 ° or 180 ° different anchor bolts, eliminates the temporary work of the jib crane for both installation and removal. This has the effect of being easier and safer to work.

[0010] The present invention also has a portal-type base portion that straddles the upper part of the concrete structure, and the concrete structure is fixed to both legs constituting the portal structure by sandwiching the concrete structure from both sides with a swash plate via a spherical bush. The present invention relates to a jib crane provided with push bolts, and an anchor bolt arranged in a direction perpendicular to a direction in which the push bolts sandwich a concrete structure.

As described above, in general, when a jib crane is temporarily installed above a concrete structure to take in materials, the concrete structure often has a wall shape. When trying to fix the jib crane by placing an anchor bolt only on the upper surface of such a wall-shaped concrete structure, there is not enough distance from the center of the jib crane post to the anchor bolt in the wall thickness direction, In the past, anchor bolts on the top surface alone could not withstand the moment applied to the foundation, so hitherto the anchor bolts were hit on the side, but there is a case where it is not necessary because there is a sufficient distance in the longitudinal direction of the wall Many. In such a case,
A necessary reaction force is imparted by being sandwiched between the push bolts only in the wall thickness direction, and a moment acting on the foundation is received in the longitudinal direction by the anchor bolts which are cast on the upper surface of the concrete structure. The position of the anchor bolts is in the longitudinal direction of the concrete wall,
The direction is perpendicular to the direction in which the push bolt sandwiches the concrete structure.

According to the present invention, the number of anchor bolts is significantly reduced as compared with the conventional method in which the push bolts are arranged in all directions since the push bolts are arranged only in a direction perpendicular to the direction in which the concrete structure is sandwiched. Cutting and curing work during installation and removal are reduced, and since the anchor bolts are only on the upper surface of the concrete structure, the work of aligning the jib crane base with the anchor bolts requires a different anchor in the conventional 90 ° or 180 ° direction. An effect is obtained that is extremely easy as compared with the case where the bolt is fitted, and as a result, the effect described above is obtained.

[0013] The present invention also relates to a base portion formed by combining two orthogonal portals straddling the upper portion of a columnar concrete structure, or an upper portion of a columnar concrete structure formed by connecting four legs thereof to each other. This is a jib crane having a square sheath-shaped base portion that covers the concrete structure, and provided on four legs with push bolts for sandwiching and fixing the concrete structure from all sides with a swash plate via spherical bushes.

When the concrete structure is not a wall but a column, and a jib crane is temporarily installed on the concrete structure, the foundation is formed so that two portals are orthogonal to each other. The two legs are connected to each other to form a square sheath that covers the upper end of the columnar concrete, and the four legs are provided with push bolts. By adopting a configuration in which the structure is sandwiched and fixed, the above effects can be obtained.

Further, according to the present invention, in each of the above-mentioned various jib cranes, a guide protruding from a leg is provided on each patch plate, and the size in the thickness direction is adjusted so that the patch plate is freely tilted without hitting the guide. It is a jib crane with a changed backing plate.

In the above-mentioned various jib cranes provided with the push bolts for sandwiching and fixing the concrete structure from both sides with the backing plate via the spherical bush, the material protrudes from the legs by the moment applied to the base when the material is hung. An upward or downward bending moment is generated at the tip of the push bolt that reaches the spherical bush, causing galling or sticking between the push bolt and the female thread cut into the leg, and controlling the subsequent tightening torque and controlling the jib crane. Disassembly may be hindered. The effect of the bending moment can be reduced by shortening the length protruding from the leg, but there is a limit to the shortening in view of the manufacturing accuracy of the foundation and the concrete structure.

Therefore, a guide having a size that is suitable for the size of the backing plate is protruded from the leg, and the guide is given sufficient strength to bend the tip of the push bolt.
In other words, when a force is applied that shifts the center of the backing plate from the center of the push bolt, the force is transmitted directly from the backing plate to the legs via the guides, thereby bending the push bolt when hanging the material. Decrease moment. For this purpose, when the backing plate is moved forward or backward by the push bolt, it does not become a resistance, and when the bending moment occurs, the center of the backing plate is slightly displaced and contacts the backing plate to receive the load. As described above, the inner method of the guide is determined by adding a small gap to the dimension of the backing plate.

The caul plate, on the other hand, is connected to the push bolt via a spherical bush and must be tilted to conform to the surface of the concrete structure. Further, the backing plate has a considerable thickness due to its strength requirement. Therefore, if the size of the backing plate in the thickness direction is fixed, the corner portion of the backing plate will hit the inner surface of the guide having only a small gap when tilted, and the tilting operation will be inhibited. Therefore, the dimension in the thickness direction of the caul plate is changed so that the caul plate does not hit the inner surface of the guide even if the caul plate is inclined, that is, the caul plate closest to the center of rotation by the spherical bush in the caul plate thickness direction. Satisfies the two requirements of free inclination and contact due to slight change of the caulking plate by making the dimensions of the guide perfect for the guide's internal method, and reducing the dimensions of the other parts so that they do not hit even if they are inclined. Can be.

According to the present invention, galling and sticking of the push bolt and the female screw portion of the leg portion are prevented, and a free inclination of the backing plate is ensured, so that the reaction force and friction force to be borne by the push bolt can be sufficiently secured. The effect is obtained.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. Note that the present invention is not limited to such an embodiment, and it goes without saying that various changes may be made to the specific structure within the scope of the present invention.

FIG. 1 is a side view of an embodiment of the present invention. The jib crane 1 includes a jib 12 for supporting a lifting device 11 such as a chain block and a post 13 for supporting the same.
The material (not shown), which is composed of the base portion 2 and is lifted by the lifting device 11 such as a chain block, is provided on the post 13 by the traveling of the lifting device 11 along the jib 12. The jib 12 is pulled by rotating the jib 12 by the swiveling mechanism 14, and is suspended at a predetermined position.

In order to clarify the structure of the base 2, FIG.
2 is shown in FIG. 2 and FIG. 3 is a view taken in the direction of arrow BB in FIG. The base part 2 is composed of a ceiling part 21 and legs 22 extending downward from both ends thereof, a gate-shaped plate 23 straddling the concrete structure 15, a reinforcing plate 24 for reinforcing the strength thereof, and a base part. Top plate 25 connecting 2 and post 13
Composed of A sufficient number of push bolts 3 are provided on both legs of the gate-shaped plate 23 to generate a reaction force and a frictional force required for the base portion. Reinforcement plate 2 for reinforcing plate 23 according to the reaction force when tightening push bolt 3
The shape, plate thickness, and number of sheets are determined. Each of the push bolts 3 is provided with a backing plate 4 via a spherical bush (not shown in FIGS. 2 and 3). By tightening the push bolt 3 while controlling the tightening torque, The jib crane 1 is fixed by sandwiching the concrete structure 15 from both sides with the backing plate 4 adapted to the wall surface of the concrete structure 15.

FIG. 4 shows an example of a combination of the push bolt 3, the spherical bush, and the backing plate 4. The spherical bush is composed of a combination of a male 32 having a shape obtained by cutting out a part of a spherical surface and a female 35 having a concave portion which is perfectly fitted to the spherical portion, and both easily absorb axial displacement by sliding easily. It is a part that transmits the pushing force from one side to the other. Here, the male part 32 of the spherical bush is fixed to the tip part 31 of the push bolt 3 by a holding plate 33 and a set screw 34, while the female part 35 of the spherical bush is fixed to the backing plate 4. A retaining plate 37 is attached to the backing plate 4 by a holding screw 38 so as to surround the male 32 of the spherical bush so that the male 32 and female 35 of the spherical bush do not fall apart.

By adopting this configuration, even if the surface of the concrete structure is not a plane perpendicular to the axial direction of the push bolt 3, the contact plate 4 changes its direction according to its surface, The force generated by tightening the bolt 3 is transmitted to the concrete structure through the backing plate 4 without waste.

FIG. 5 is a drawing showing a base portion of a side view of another embodiment of the present invention. FIG. 6 is a view taken along the line CC of FIG. The base part 5 of the present embodiment includes a gate-shaped plate 51 that straddles the concrete structure 15.
And a reinforcing plate 52 that reinforces the strength thereof, and a combination of a top plate 53 that connects the base portion 5 and the post 13. Both legs of the portal-shaped plate 51 have reaction forces required for the base portion. And a sufficient number of push bolts 3 to generate a frictional force, and these push bolts 3 are provided with a backing plate 4 via a spherical bushing in the same manner as the base part 2 of the case described above. is there. In addition to these components, in the base portion 5 of the present embodiment, the anchor bolts 6 are arranged in a direction perpendicular to the direction in which the push bolt 3 sandwiches the concrete structure 15, that is, in the longitudinal direction of the wall of the concrete structure 15. Then, the side plate 54 having the receiving plate 55 is extended from the portal section toward the anchor bolt 6, and the anchor bolt 6
The base plate 5 is fixed by tightening the receiving plate 55 with the nut 61.

According to this embodiment, although the anchor bolts are used for fixing the base portion, the number of anchor bolts is greatly reduced as compared with the conventional construction method relying only on the anchor bolts.
In addition, since the few anchor bolts are planted on only one surface, that is, the upper surface of the concrete structure, it is much easier to align the foundation with the anchor bolts.

FIG. 7 is a side view of a base part of still another embodiment of the present invention, and FIG. 8 is a view of the base part taken along the line DD. In this embodiment, the concrete structure 16 has a columnar shape, and the base part 7 of the jib crane has a sheath-like plate 71 covering its upper part, a reinforcing plate 72 for reinforcing its strength, and a base part 7.
And a top plate 73 that connects the post 13 and the legs of the plate 71 formed on the sheath are provided with a sufficient number of push bolts 3 to generate a reaction force and a frictional force necessary for the base portion. Have been. The place where the contact plate 4 is attached to these push bolts 3 via a spherical bush (not shown) is the same as the base part of the case described above. In this case, since the concrete structure to be fixed was columnar, two portal-type foundations straddling the upper part were arranged orthogonally to each other, and the legs adjacent to each other were connected. It is also conceivable that the strength of is increased by coupling.

By tightening the push bolts 3 provided on the four surfaces while controlling the torque, the jib crane can be easily fixed without using anchor bolts.

FIG. 9 shows an example of a combination of a guide and a contact plate when a guide is provided on the contact plate. (A) shows a front view, and (b) shows the EE arrow view. The male part 32 of the spherical bush is fixed to the tip part 31 of the push bolt, and the female part 35 to be combined therewith is fixed to the backing plate 40. A retaining plate 39 is attached to the contact plate 40 by a holding screw 38 so that the push bolt and the contact plate 40 do not fall apart. A guide 45 is fixed to the gate-shaped plate 23 in the vicinity of the backing plate 40. The shape of the guide is determined according to the shape of the backing plate 40 because the guide comes into contact when the center of the backing plate 40 is displaced from the center of the push bolt and receives the force. Generally, since the backing plate is formed in a disk shape as in this example, the guide takes the shape of a ring surrounding the guide plate. Since the displacement of the caul plate caused by the moment applied to the base when the material is suspended is either upward or downward, the guide is not a complete ring, but the upper and lower parts of the ring as shown in the figure. The effect is the same even when the shape is taken out only, and it is preferable to divide the guide vertically in consideration of the easiness of the work when installing the guide.

The state in which the backing plate 40 is inclined according to the surface of the concrete structure to be pressed is indicated by a two-dot chain line 43. For the purpose of providing a guide, the backing plate 40 and the guide 4
The gap of 5 should be as narrow as possible in the processing without touching them, but if it is made narrower, the contact plate may be tilted.
In the case of 3, there is a possibility that the side surface of the backing plate comes into contact with the guide. Therefore, in order to avoid contact and ensure a free inclination, the shape of the backing plate 40 is changed in the thickness direction. In the case of this figure, the center of rotation of the contact plate by the spherical bush is on the back side of the contact plate, that is, the stopper plate 39.
The inner diameter of the guide 45 is set so as to have a slight gap based on the outer diameter of the back part of the backing plate 40, A recess 42 is provided to avoid contact with the guide 45 in the inclined state 43. Further, the surface portion of the backing plate 40 that does not contact the guide even when inclined is the same as the outer diameter of the back portion. By forming the backing plate in a disk shape, it is easy to process the depression on the side surface.

By adopting this embodiment, in addition to the above-described effects, an effect is obtained that the manufacture of the backing plate and the mounting of the guide are easy.

[0032]

According to the present invention, it is no longer necessary to temporarily lay anchor bolts on a concrete structure, or even if they are laid, the number of anchor bolts is greatly reduced.
Eliminating or reducing the cutting and curing work at the time of casting and removal, it takes a long time to adjust the jib crane base to the anchor bolts, especially to adjust the anchor bolts at different angles of 90 ° or 180 °. As a result, there is an effect that the temporary work of the jib crane is easier in both mounting and dismounting, and the work can be performed safely. Further, according to the present invention, it is possible to prevent the push bolt and the female screw portion of the leg portion from galling or sticking, and to ensure a free inclination of the backing plate to sufficiently secure a reaction force and a frictional force to be borne by the push bolt. Is obtained.

[Brief description of the drawings]

FIG. 1 is a side view of an embodiment of the present invention.

FIG. 2 is a view taken along the line AA of FIG. 1;

FIG. 3 is a view taken in the direction of arrows BB in FIG. 2;

4 is a drawing showing an example of a combination of a push bolt 3, a spherical bush, and a contact plate 4. FIG.

FIG. 5 is a side view of a base according to another embodiment of the present invention.

6 is a view taken in the direction of the arrows CC in FIG. 5;

FIG. 7 is a side view of a base part of still another embodiment of the present invention.

FIG. 8 is a view as seen in the direction of arrows DD in FIG. 7;

FIG. 9 is a drawing showing an example of a combination of a guide and a backing plate when a guide is provided.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Jib crane 2 Base part 3 Push bolt 4 Backing plate 5 Base part 6 Anchor bolt 7 Base part 11 Lifting equipment 12 Jib 13 Post 14 Swivel mechanism 15 Concrete structure 16 Columnar concrete structure 21 Ceiling part 22 Leg part 23 Gate type 24 Reinforcement plate 25 Top plate 31 Tip end of push bolt 32 Male of spherical bush 33 Holding plate 34 Set screw 35 Female of spherical bush 37 Lock plate 38 Lock screw 39 Lock plate 40 Thickness in the thickness direction 42 Circumferential depression of the abutment plate 43 State in which the abutment plate is inclined 45 Guide 51 Plate formed in a gate shape 52 Reinforcement plate 53 Top plate 54 Side plate 55 Receiving plate 61 Nut 71 Sheath shape Formed plate 72 Reinforcement plate 73 Top plate

Claims (4)

[Claims] 1. A push bolt which has a gate-shaped base part straddling the upper part of a concrete structure, and fixes the concrete structure by sandwiching the concrete structure from both sides with a backing plate via spherical bushes on both legs constituting the gate shape. Jib crane provided. 2. The jib crane according to claim 1, wherein the push bolt has an anchor bolt arranged in a direction perpendicular to a direction in which the concrete structure is sandwiched. 3. A square base covering the upper part of a pillar-shaped concrete structure formed by connecting two orthogonal portals straddling the upper part of a pillar-shaped concrete structure or a pillar-shaped concrete structure having four legs connected to each other. A jib crane that has a sheath-shaped foundation and is provided with push bolts on its four legs that clamp and fix concrete structures from four sides with a patch plate via spherical bushes. 4. A backing plate, wherein each backing plate is provided with a guide projecting from a leg, and the backing plate has a backing plate whose size is changed in the thickness direction so that the backing plate can be freely tilted without hitting the guide. The jib crane according to claim 3.