JP2000177979A - Portal crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To switch the advancing direction of a portal crane perpendicularly without allowing a conveyance object to interfere with existing columns by expandably forming a set of opposite frame elements of an architrave-shaped frame having a hanging mechanism. SOLUTION: Rollers 10 provided on a set of frame element 9 of a lower frame 7 are slidably assembled to a set of frame elements 8 of an upper frame 6 of a frame 1. Tips of guide members 11 shrinkably provided on the upper frame 6 are fixed to brackets 12 provided on the lower frame 7, thus a set of frame elements 8, 9 are made expandable. Leg sections 3 are vertically divided at the middle, upper bases 15 are horizontally provided at the lower ends of upper split leg sections 14, and lower bases 20 are horizontally provided on lower split leg sections. Drive gears of motors 22 fitted to the upper split leg sections 14 are engaged with spur gears formed on the lower bases 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a portal crane.

[0002]

2. Description of the Related Art It is well known that heavy construction members such as floor slabs and columns are transported by overhead cranes or portal cranes at building sites.

[0003]

The overhead crane moves along the rails installed on the ceiling side, and the portal crane moves along the rails installed on the floor side. It is possible to switch the traveling direction during the transportation of building members by an overhead crane or a portal crane. However, when the object to be transported is a floor slab or a column, when the traveling direction of an overhead crane or a portal crane is switched around the column (span) already installed at the construction site, the rotating floor slab or column is In some cases, it is impossible to switch the traveling direction. In such cases, the overhead crane and portal crane rails should be installed linearly,
A truck rail is installed at a position where the traveling direction is switched in a direction orthogonal to the rails of the overhead crane and the portal crane, and the overhead crane and the portal crane are used in combination with a truck called a traverser. This will be described with reference to FIG. FIG. 9 shows two portal cranes 100 and 10.
1 is movably installed in a state of being linearly parallel, and one trolley 192 is movably installed in a direction orthogonal to the two portal cranes 100 and 101. Then, one portal crane 100 transports the transport target such as a floor slab or a pillar, and the transport target is transshipped to the bogie 102 by the one portal crane 100 at that location. Next, trolley 1
02 transports the transport object to the side of the other portal crane 101, where the transport object is transshipped from the carriage 1-2 to the other portal crane 101. Thereafter, the other portal crane 101 transports the transport target. in this way,
If the traveling direction cannot be changed in the process of transporting the object to be transported by the overhead crane or the portal crane, it is necessary to transship the object to be transported, and the transportation operation has to be troublesome.

[0004] Therefore, an object of the present invention is to provide a portal crane which can switch the traveling direction without transshipping an object to be transported at a building site.

[0005]

According to the first aspect of the present invention, a frame-shaped frame, four legs connected to the frame, moving means attached to each leg, and a frame. With a load suspending mechanism provided, and
It is characterized in that the set of frame elements is formed to be stretchable. According to a second aspect of the present invention, each leg according to the first aspect is formed in a bent crab-foot shape, and the crab-foot bent portion is formed to be rotatable. . According to a third aspect of the present invention, each moving means according to the first aspect is formed by an air bearing. The invention according to a fourth aspect is characterized in that the load suspending mechanism is attached to the frame according to the first aspect via a rotation mechanism.

[0006]

1 and 2 show a first embodiment of the present invention. FIG. 1 shows an external view of a skeleton of a portal crane.
FIG. 2 shows a front view of a floor slab 30 as an object to be transported lifted by a portal crane, FIG. 3 shows a front view from a direction A in FIG. 2, and FIGS. Fig. 3 shows a transport process when switching twice at right angles. 1 does not show the upper base 15 and the lower base 20 in FIG. 2, and FIG. 3 does not show the guide member 11 and the bracket 12 in FIG.

The portal crane will be described with reference to FIG. The portal crane includes a frame 1 having a frame shape, four legs 3 connected to the frame 1, a moving means 4 attached to each leg 3, and a load suspending mechanism 5 provided on the frame 1.
A pair of opposed frame elements 8 and 9 of the frame 1 are formed to be extendable and contractable, each leg 3 is formed in a crank-shaped crab-foot shape, and a crab-foot-shaped bend. The part is formed rotatably, and each moving means 4 is formed by an air bearing.

In the case of the first embodiment, the frame 1 is divided into a horseshoe-shaped first divided frame 6 in plan view and a horseshoe-shaped second divided frame 7 in plan view. The first divided frame 6 and the second divided frame 7 are arranged vertically with the opening of the first divided frame 6 and the opening of the second divided frame 7 facing each other. One set of frame elements 8 forming a pair of side portions facing each other in the upper first divided frame 6 includes a pair of frame elements forming a pair of side portions facing each other in the lower second divided frame. 9
Are assembled so as to be slidably engaged (see FIG. 3). Further, the distal end of a guide member 11 provided on the first divided frame 6 so as to be contractible is fixedly attached to a bracket 12 provided on the second divided frame 7. Therefore, in a state where one of the first divided frame 6 and the second divided frame 7 is fixed so as not to move, the operator points the other divided frame to the arrow X.
By pushing or pulling in the direction indicated by, a pair of frame elements 8 and 9 of the frame 1 facing each other can be expanded and contracted. Instead of the operator pushing or pulling the other divided frame, the guide member 11 may be constituted by an actuator that linearly expands and contracts like an air cylinder, a hydraulic cylinder, or an electric cylinder.

As shown in FIG. 2, each leg 3 is vertically divided at its middle. An upper base 15 is provided horizontally at the lower end of the upper split leg 14. The lower split leg 16 includes an upper vertical portion 17, a horizontal portion 18 extending outward from a lower end of the upper vertical portion 17, and a lower vertical portion extending downward from the tip of the horizontal portion 18. 19 is provided.
A lower base 20 is provided horizontally at the upper end of the upper vertical portion 17. Since the lower base 20 and the upper base 15 are rotatably connected via the shaft 21, the lower split leg 16 is moved horizontally with respect to the upper split leg 14 about the shaft 21 as indicated by an arrow W. It is rotatably connected. The lower base 20 is formed of a spur gear, and the spur gear meshes with a drive gear 23 that is integrally rotatably mounted on an output end of a motor 22 mounted on the upper split leg 14. Therefore, the operation of the motor 22 causes the lower split leg 1
6 may be configured to be driven to rotate in the horizontal direction about the shaft 21.

The load suspending mechanism 5 is attached to the second divided frame 7. The second divided frame 7 has a plurality of connecting members 24 passed over a pair of frame elements 9 facing each other. A winch 25 is attached to one of the connecting members 24, and the fixed pulley 2 is attached to a plurality of intermediate connecting members 24.
6 are individually attached, one end of a wire 27 is anchored to the connecting member 24 at the distal end, and the other end of the wire 27 is alternately wound around the moving pulleys 28 and the constant pulley 26 every other one. Later, it is wound around the winch cylinder of the winch 25. Therefore,
The loading mechanism 5 includes a winch 25, a fixed pulley 26, and a wire 27.
And a moving pulley 28. Then, when the winch 25 is hoisted up in a state in which the plurality of suspension wires 29 extending below the rotation center of the moving pulley 28 are moored to the floor slab 30 as a load carrying object member, The other end of the wire 27 is wound around the winch 25, and the moving pulley 28 moves upward in accordance with the winding amount, so that the load suspension mechanism 5 lifts the floor slab 30 horizontally from the running surface 31.

Referring to FIGS. 4 to 6, a description will be given of a transporting process when the traveling direction of the portal crane in the first embodiment is switched twice at right angles. In this transportation process, the portal crane that lifts the floor slab 30 shown in FIG.
As an example, a process in which the area is transferred from the area a to the area d via the areas b and c as indicated by an arrow Y in FIG. In FIGS. 4 to 6, reference numeral 32 denotes a plurality of columns already provided at the construction site, and a dashed line denotes a center line connecting the columns 32. Also, FIG.
In FIG. 6 to FIG. 6, when the floor slab 30 (see FIG. 2) moves linearly, the floor slab 30 has vertical and horizontal dimensions that allow it to pass between the columns consisting of a pair of columns 32 facing each other. , The floor slab 30 is formed in such a size that the floor slab 30 cannot rotate due to interference with any one of a pair of columns 32 constituting the space between the columns. 4 to 6, each of the four legs 3 is provided with 3a, 3b, 3c and 3d.

At step 102 in FIG. 4, each leg 3 of the portal crane is oriented in the direction of travel of arrow X1. In step 103, the portal crane goes straight from the area a to the area b (see step 101), and at the position where the legs 3a, 3b on the front side in the traveling direction of the arrow X1 can rotate, the portal crane stops. , 3b rotate 90 degrees horizontally in the direction of arrow W1. In step 104, after the rotation of the legs 3a, 3b is completed, the portal crane moves straight again in the direction of the arrow X1 and stops until the legs 3a, 3b approach the column 32. The stop state of the portal crane is step 105. In step 106, while the first divided frame 6 on the front side in the traveling direction of the arrow X1 is stopped, the second divided frame 7 goes straight to the arrow X1, and the legs 3c and 3d on the rear side in the traveling direction of the arrow X1 are rotatable. At the position, after the straight traveling of the second divided frame 7 stops,
The legs 3c and 3d rotate horizontally by 90 degrees in the direction of arrow W2. The movement of the second divided frame 7 in step 106 is a reduction operation of the frame 1 (see FIG. 1) including the first and second divided frames 6 and 7. Step 1 in FIG.
In 07, after the rotation of the legs 3c, 3d is completed, the legs 3c, 3d
Until d approaches the pillar 32 on the rear side in the traveling direction of the arrow X1,
The second divided frame 7 moves straight in the direction of arrow X2 (opposite to X1) and stops. In step 108, after the straight traveling of the second divided frame 7 is stopped, the portal frame goes straight in the direction of arrow X3 (the direction orthogonal to arrow X1). This is the first switching of the traveling direction in which the traveling direction is switched from the direction of arrow X1 to the direction of arrow X3. In step 109, after the portal crane advances straight from section b to section a (see step 101) and stops, the second divided frame 7 moves straight in the direction of arrow X1 until the legs 3c and 3d can rotate. Stop. In step 110, the legs 3c and 3d rotate 90 degrees horizontally in the direction of arrow W3. In step 111, after the rotation of the legs 3c and 3d is completed, the second divided frame 7 moves straight in the direction of the arrow X2 while the first divided frame 6 is stopped. This is a decompression operation of the frame 1 including the first and second divided frames 6 and 7. Second divided frame 7
Step 112 is the end of the straight traveling. In step 113, after the portal crane stops in the traveling direction of arrow X2 until the legs 3a, 3b on the rear side in the traveling direction of arrow X2 are rotatable, the legs 3a, 3b move in the direction of arrow W4. To 90
Rotate horizontally by degrees. In step 114, after the rotation of the legs 3a, 3b is completed, the portal crane moves straight again in the direction of arrow X2. At step 115, the portal crane goes straight from section c to section d (see step 101). This is the second traveling direction switching in which the traveling direction is switched from the direction of arrow X3 to the direction of arrow X2.

In short, according to the first embodiment, the floor slab 3
If the vertical and horizontal dimensions of a heavy object to be transported, such as 0 or an unillustrated column or beam, can move straight between the existing columns at the construction site, use a portal crane around the column. When the switch is performed, the pair of frame elements 8, 9 facing each other in the frame 1 is extended and contracted without rotating the portal crane, so that the object to be transported does not interfere with the column 32, The direction of travel can be switched at right angles. In the transport process in which the traveling direction does not need to be switched and the frame elements 8 and 9 are extended and the length of the frame 1 in the traveling direction is set to be long in the transporting process in which the vehicle is traveling straight, the straight traveling of the portal frame is stabilized, and We can carry thing safely.

According to the first embodiment, the crab-shaped bent portion formed by the horizontal portion 18 and the lower vertical portion 19 of each leg 3 is connected to the upper vertical portion 17 so as to be rotatable in the horizontal direction. Therefore, when the traveling direction of the portal crane is switched, the traveling direction of the portal crane can be smoothly switched by using both the expansion and contraction operation of the frame elements 8 and 9 and the rotation operation of the bent portion of the leg 3. . In the straight traveling process, the extension of the frame elements 8 and 9 and the securing of the rotation stop position of the leg 3 are used together,
The wheelbase, which is the distance between the moving means 4 in the traveling direction, can be set long, so that the straight movement of the portal frame is more stable, and the transport target can be transported more safely.

According to the first embodiment, since the moving means 4 is formed by an air bearing, it is necessary to keep supplying compressed air from the compressor (not shown) to the air bearing during the movement of the portal crane. However, like a hovercraft, an air layer is formed between the portal crane and the traveling surface 31 by pressurized air blown from an air bearing, and the motor or engine Thus, the portal crane, which hangs a heavy object to be transported, can be easily moved manually without using a drive source for movement, and the operability is improved.

FIGS. 7 and 8 show a second embodiment of the present invention. FIG. 7 shows a floor slab 3 as an object to be transported by a portal crane.
FIG. 8 shows the front from the direction B in FIG. 7. The second embodiment is characterized in that the load suspending mechanism 5 is attached to the second divided frame 7 via the rotating mechanism 40. The rotating mechanism 40 includes a fixed base 41 fixed to the connecting member 23 of the second divided frame 7 and a fixed base 4
1 includes a circular rail 42, a plurality of rollers 43 slidably engaged with the circular rail 42, and a turntable 44 to which the rollers 43 are fixed. And the roller 43
Moves along the circular rail 42, the turntable 44 rotates in the horizontal direction, and the load suspending mechanism 5 mounted on the turntable 44 rotates together with the turntable 44. Therefore, in a state where the floor slab 30 is lifted from the running surface 31 by the load suspending mechanism 5, the rotating mechanism 40 is rotated without rotating the portal crane, and the floor slab 3 is lifted.
The direction of 0 can be changed.

In the first and second embodiments, the first and second divided frames 6 and 7 are arranged vertically, but the divided element 8 of the first frame is located outside or inside the frame element 9 of the second divided frame 7. Even if the first and second divided frames 6 and 7 arranged in parallel are arranged in the horizontal direction,
Further, the first and second divided frames 6 and 7 in which the divided elements 8 of the first frame are inserted and arranged either inside or outside the frame elements 9 of the second divided frame 7 may be fitted.

In the first and second embodiments, the leg 3 is formed in a crab-foot shape. However, even if the leg 3 has a straight vertical shape,
Further, the leg 3 may have a non-rotational configuration.

In the first and second embodiments, the rotation of the leg 3 is of the power type, but the rotation of the leg 3 may be of the manual type.

In the first and second embodiments, the moving means 4 is formed by an air bearing. However, the moving means 4 may be a roller type such as a wheel. It may be driven by a driving source.

[0021]

As described above, according to the first aspect of the present invention, the frame-shaped frame having the load suspending mechanism is opposed to the frame-shaped frame.
Since the set of frame elements is formed to be extendable, if the size of the object to be transported lifted by the load lifting mechanism can go straight between the existing pillars at the building site, When switching around the column, the traveling direction of the portal crane is switched at a right angle without rotating the portal crane and expanding / contracting the frame element so that the object to be transported does not interfere with the existing pillar. Can be done. In addition, there is no need to switch the traveling direction, and in the transporting process of traveling straight, if the frame element is extended and the length of the traveling direction of the frame is set to be long, the straight traveling of the portal frame is stabilized, and the object to be transported is transported. Can be transported safely. According to the second aspect of the present invention, since the crab-shaped bent portion of each leg is formed to be rotatable, when switching the traveling direction of the portal crane, the expansion and contraction operation of the frame element and the leg are performed. When the rotation operation of the bent portion is used together, the switching of the traveling direction of the portal crane can be smoothly performed. In addition, in the straight traveling process, the extension of the frame element and the securing of the rotation stop position of the legs are used together, so that the wheel base in the traveling direction can be set longer, the straight traveling of the portal frame becomes more stable, and the transport object can be transported. It can be transported more safely. According to the third aspect of the present invention, since the moving means is formed by the air bearing, the portal crane is floated by the pressurized air blown out from the air bearing, and the moving drive source such as the motor or the engine is driven. Without using it, a portal crane that hangs a heavy object to be transported can be easily moved manually and operability can be improved.
According to the invention of claim 4, since the load suspending mechanism is attached to the frame via the rotating mechanism, in a state where the object to be transported is lifted by the load suspending mechanism, the portal crane does not rotate, and By rotating the rotation mechanism, the direction of the transport target portion can be changed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a portal crane according to a first embodiment of the present invention.

FIG. 2 is a front view of the portal crane that lifts the floor slab of the first embodiment.

FIG. 3 is a side view of the portal crane that lifts the floor slab of the first embodiment.

FIG. 4 is a schematic view showing a transportation process according to the first embodiment.

FIG. 5 is a schematic view showing a transportation process according to the first embodiment.

FIG. 6 is a schematic view showing a transportation process according to the first embodiment.

FIG. 7 is a front view of a portal crane that lifts a floor slab according to the first embodiment of the present invention.

FIG. 8 is a side view of the portal crane that lifts the floor slab of the second embodiment.

FIG. 9 is a schematic view showing a conventional transport mode.

[Explanation of symbols]

1 frame, 3 legs, 4 moving means, 5 loading mechanism, 8 frame elements, 9 frame elements, 30 floor slab (object to be transported), 40 rotating mechanism.

Claims (4)

[Claims] A frame-shaped frame, four legs coupled to the frame, and a moving means attached to each leg.
A portal crane comprising: a load suspending mechanism provided on a frame; and a pair of frame elements facing each other of the frame are formed to be extendable and contractible. 2. The portal crane according to claim 1, wherein each leg is formed in a bent crab-foot shape and the crab-foot-shaped bent portion is formed to be rotatable. 3. The portal crane according to claim 1, wherein each moving means is formed by an air bearing. 4. The portal crane according to claim 1, wherein the load suspending mechanism is attached to the frame via a rotating mechanism.