JP5690084B2 - Attachment for forklift and load handling method using the same - Google Patents

Description

  TECHNICAL FIELD The present invention relates to an attachment for a forklift and a load handling method using the same, and more specifically, an attachment provided on a forklift for handling a curved concrete product, and a curved concrete product by a forklift equipped with the attachment. It is related with the lifting and transporting method.

A forklift, also called a forklift truck, is a special vehicle equipped with a mast at the front of a powered vehicle body and configured to move up and down a fork for holding luggage along this mast. For transportation, it is widely used in factories, warehouses, collection sites, construction sites, etc.
In addition to the fork, various types of attachments can be attached to the mast depending on the form of the luggage and the work content.
For example, Patent Document 1 below discloses an attachment configured as a tire stacking device, Patent Documents 2 and 3 disclose snow removal attachments, and Patent Document 4 further discloses. Discloses an attachment for handling a drum can.

However, forklift attachments for handling, for example, curved concrete products constituting the walls of tunnels and large drains, that is, curved concrete products whose inner and outer peripheral surfaces are part of a substantially cylindrical curved surface, Never been offered before.
Such curved concrete products are large, heavy, and have a special shape, so it is difficult to balance when handling with a forklift, and if the balance is lost, the product may fall or fall. Not only was the product damaged, it was very dangerous.
Therefore, there is a problem that handling of such a curved concrete product with a forklift requires great care and is troublesome, and usually a large crane vehicle or the like is used for handling the load.

Japanese Patent Laid-Open No. 05-139698 Japanese Patent Laid-Open No. 10-088543 Japanese Patent Laying-Open No. 2005-220711 JP 2000-016792 A

Therefore, an object of the present invention is to stably attach a curved concrete product as described above by a forklift attachment that can lift and transport a curved concrete product in a stable state, and a forklift equipped with the attachment. The purpose is to provide a method that can be lifted and transported.
In the present invention, the term “curved concrete product” is not necessarily limited to only a concrete product, but broadly encompasses all heavy objects having a generally curved shape.

To achieve the above object, a forklift attachment for handling a curved concrete product according to the present invention comprises:
A horizontal frame attached in a form that spans between the left and right fork claws of the forklift,
It has a hanging part that is detachably attached to the horizontal frame at both ends, and is folded back into a U-shape at a substantially central part when used, and at that folded part, a curved concrete product as a lifting object is lifted and held. Two lifting belts,
Wherein the two lifting the hooking parts at both ends of the belt, is composed of a hanging member provided in at least two places on the transverse frame to removably retain,
The horizontal frame uses an H-shaped steel material composed of a web portion and a pair of flange portions provided on both sides of the web portion, with the web portion side in a horizontal state, and is positioned below the web portion side and Fork claw insertion holes through which the fork claws are inserted are provided on the flange portions .
In this case, the present invention is such that the installation position of the hanger provided on each flange portion is set to a position offset by an angle α on the normal R when the center of curvature of the curved concrete product is O. Features.

Further, in order to achieve the above phrase suitability, a forklift equipped with the forklift attachment according to the present invention lifts and conveys a curved concrete product whose inner peripheral surface and outer peripheral surface are part of a substantially cylindrical curved surface. The method is
Attaching the two left and right fork claws of the forklift to the insertion hole provided in the horizontal frame so as to hang and thereby integrating the horizontal frame and the left and right fork claws;
Holding the curved concrete product in an upright state such that a generatrix of the substantially cylindrical curved surface is substantially vertical;
Attaching one hanging portion of each of the two lifting belts to separate lifting tools on the lateral frame attached to the fork claws of a forklift;
By passing the other hanging portion of each of the two lifting belts under the concrete product held in the standing state and attaching them to separate lifting tools provided on a horizontal frame, the lifting belt is substantially omitted. It is attached to the concrete product in a state of being folded in a U-shape at the center, and the center of gravity of the concrete product is located within the width region connecting the locations where the two lifting belts lift the concrete product. Adjusting so that,
Raising the fork of the forklift to lift the concrete product to a desired height with the two lifting belts, and transporting the concrete product to a desired location by running the forklift in that state;
It is comprised from these.

  When the load handling attachment according to the present invention is used, when the concrete product is lifted by the two lifting belts folded in a U-shape at the substantially central portion, the two places that are the attachment points of the lifting belt to the concrete product are connected. By adjusting so that the center of gravity of the concrete product is positioned within the width region, the concrete product is in a state equivalent to that supported by the center of gravity, and does not fall down on either side. Therefore, it is not necessary to firmly tie the concrete product and the lifting belt with another rope or the like, and the concrete that is curved in a stable state only by these two lifting belts that are simply folded back in a U shape. The product can be lifted and transported. Therefore, it is not necessary to use a large crane vehicle or the like, the working efficiency is improved, and the cost can be saved.

It is explanatory drawing which shows one Example of the horizontal frame which comprises a part of attachment for forklifts concerning this invention. It is explanatory drawing which shows one Example of the two lifting belts which comprise a part of attachment for forklifts concerning this invention. It is explanatory drawing which shows an example of the fall-off prevention means of the horizontal frame from the fork nail | claw of a forklift. It is explanatory drawing which shows the desirable setting position of the attachment position hole of the hanging tool to a horizontal frame. It is explanatory drawing which shows the example of the general forklift truck which attaches and uses the attachment for forklifts which concerns on this invention. It is explanatory drawing which shows the state which attached the attachment for forklifts which concerns on this invention to the forklift shown in FIG. It is explanatory drawing which shows the process of raising the curved concrete product which should be lifted and conveyed and attaching the attachment for forklifts which concerns on this to this. It is explanatory drawing which shows the state which attached the attachment for forklifts which concerns on this invention to the curved concrete product. It is explanatory drawing which shows the positional relationship of the mounting position of the lifting belt to the curved concrete product, and the gravity center of concrete product. It is explanatory drawing which shows the state which lifts and conveys the curved concrete product.

The details of the forklift attachment according to the present invention will be described below with reference to the accompanying drawings.
The present invention is not limited to the illustrated embodiment, and each component can be replaced with another member having an equivalent function.

The forklift attachment according to the present invention has a horizontal frame 11 as shown in FIG. 1 as an example, two lifting belts 12A and 12B as shown as an example in FIG. 2, and a suspension provided on the horizontal frame 11. and ingredients 112a~112d, consists of.
As shown in FIGS. 6-8, the attachment 10 which consists of these components is attached to a pair of fork claw 26a, 26b of the forklift 20, and is suitably used for lifting and transporting the curved concrete product 30.

In the case of the embodiment shown in FIG. 1, the horizontal frame 11 has a frame portion 111, as shown in FIG. 3 , in particular, a web 111c and flange portions 111d and 111d provided on both sides of the web portion 111c. The forklift 20 is made of an H-shaped steel material having a web portion 111c side in a horizontal state and is located on the lower side of the web 111c side and penetrates the flange portions 111d and 111d. Insertion holes 111a and 111b for inserting the fork claws 26a and 26b are provided. In addition, the flanges 111d and 111d near both ends of the frame portion 111 are attached with suspenders 112a to 112d made of shackles or chains with hooks attached to the lower end portions . A handle 113 made of a wire rope or the like is attached near the upper side of the central portion of the frame portion 111 so that the horizontal frame 11 itself can be easily carried by a crane or attached to a forklift.
The horizontal frame 11 is attached so as to span between the two fork claws by inserting the left and right fork claws 26a and 26b of the forklift 20 into the fork claw insertion holes 111a and 111b, respectively. Thus, the horizontal frame 11 and the two left and right fork claws 26a and 26b can be integrated.
In order to prevent the horizontal frame 11 from falling off from the fork claws during operations such as lifting and transporting concrete products, for example, as shown in FIG. 3, a pin hole 261 is drilled near the tips of the fork claws 26a and 26b. Then, the drop-off prevention pin 114 is inserted into the hole to prevent the horizontal frame 11 from falling off. Alternatively, when the forklift is equipped with a fork shifter that can increase or decrease the distance between the left and right fork claws 26a, 26b, the fork claws 26a, 26b inserted into the fork claw insertion holes 111a, 111b of the horizontal frame 11 are By spreading it out to a certain extent, it is possible to prevent the horizontal frame 11 from dropping to a certain extent. Furthermore, in the case of a forklift capable of fixing the horizontal frame 11 and the fork claws 26a and 26b with screws, a giant clam vise, etc. or tilting the mast back and forth (tilt), tilt the mast somewhat backwards, The horizontal frame 11 may be prevented from falling off by inclining the fork claw so that the tip side of the fork claw is lifted somewhat.

Since the two lifting belts 12A and 12B shown in FIG. 2 have the same configuration, only the lifting belt 12A will be described here.
As the lifting belt 12A (a belt is preferable to a rope), a nylon sling 123 made of nylon fiber is used for the product weight, and the outside thereof is wrapped with a long bag-like cover cloth 124, and hanging parts 121a at both ends. , 121b, a ring or shackle 122 is attached.
The cover cloth 124 is for preventing damage to the object to be lifted and transported (curved concrete product) and for preventing wear of the nylon sling, and the ring or shackle 122 suspends the lifting belt 12A. For hooking the hooks of the tools 112a to 112d.
The lengths of these two lifting belts 12A and 12B are the same, but there are cases where it is necessary to change the length according to the object to be lifted and transported, so two lifting belts of the required length are required. They are prepared one by one.

The hoisting tools 112a to 112d provided in at least two places on the horizontal frame 11 are for detachably holding the hanging portions 121a and 121b at both ends of the two lifting belts 12A and 12B. In the illustrated embodiment, a hook with a stopper is attached to the lower end of the chain. However, the form is not limited to this, and the hanging portions 121a and 121b of the two lifting belts 12A and 12B are engaged. As long as the configuration can be stopped, various forms can be adopted. For example, when hooks are attached to the hooks 121a and 121b at both ends of the lifting belts 12A and 12B instead of the ring 122, holes for hooking the hooks on the frame 111 are provided on the side of the horizontal frame 11. In that case, the hole itself opened in the frame part 111 becomes a hanger .
In the illustrated embodiment, the distance between the left and right suspension tools 112a and 112b on the left side of the horizontal frame 11 and the right suspension tools 112c and 112d is two for the curved concrete product to be lifted and transported. It is necessary to appropriately change the position depending on the position where the lifting belts 12A and 12B are attached. For this reason, it is recommended that suspensions be attached in advance at two or more positions with different left and right intervals. Alternatively, a plurality of types of horizontal frames 11 having different distances between the left and right suspensions may be prepared and used according to the size and shape of the concrete product.
Moreover, the position hole provided in the horizontal frame 11 for attachment of these suspenders 112a-112d is determined according to the size of a concrete product, More preferably, it provides on the normal line according to the curvature of a product. Is desirable.
This point will be described with reference to FIG. 4. The position of the fork claws 26 a and 26 b on the frame portion 111 of the horizontal frame 11 is parallel to the axial direction T (the position indicated by the black triangle in the figure). Rather than providing a position hole, when the center of curvature of the concrete product is O, it is provided at a position offset by an angle α on the normal R (a position indicated by a black circle in the figure). . Thus, the lifting belts 12A and 12B are hung on the normal line R, and the concrete product can be lifted stably.

FIG. 5 shows a general forklift 20 to which the forklift attachment according to the present invention is attached.
The forklift 20 has a mast 23 at the front of a vehicle body 21 having a driver's seat 22, and a fork mounting frame 25 to which a pair of left and right fork claws 26 a and 26 b is attached can be lifted and lowered along the mast 23. Yes. The roller chain 24 is a part of a drive mechanism for raising and lowering the fork mounting frame 25. The roller chain 24 is wound around a sprocket not shown in the figure, and the fork mounting frame 25 is raised and lowered by forward and reverse rotation of the sprocket. Yes.

6 to 8, the forklift 20 shown in FIG. 5 is attached with the attachment 10 of the present invention shown in FIG. 1 and FIG. 2 and the working process for lifting the curved concrete product 30 using this is sequentially shown. .
As shown in FIG. 6, the attachment according to the present invention is mounted on a forklift by attaching the lateral frame 11 so as to span between the fork claws 26a and 26b of the forklift. That is, as described above, the fork pawls 26a and 26b of the forklift are inserted into the fork pawl insertion holes 111a and 111b of the horizontal frame 11, respectively, and then fixed using screws or the like, or the mast 23 is slightly inclined rearward. The horizontal frame 11 is prevented from falling off the fork claws 26a and 26b.
After that, as shown in the figure, one hanging portion 121a of each of the two lifting belts 12A, 12B is hooked and attached to separate hanging tools 112a, 112c provided on the horizontal frame 11.

On the other hand, the curved concrete product 30 to be lifted and transported is erected using a reversing machine or the like (not shown) as shown in FIG. 7, and the other hanging portion 121b of the lifting belts 12A and 12B is passed through the lower part. Pull it forward.
That is, the concrete product 30 to be handled in the present invention generally has a curved shape in which the inner peripheral surface 30a and the outer peripheral surface 30b are part of a substantially cylindrical curved surface. Is lifted by using a reversing machine or the like so that the substantially cylindrical curved busbar 30e (see FIG. 7) is substantially vertical, and is held in the standing state. Under the concrete product 30, the other hanging portion 121b of the lifting belts 12A and 12B is passed through and pulled out forward.
In order to easily perform the operation of passing the lifting belts 12A and 12B under the concrete product 30, the raised concrete product is temporarily placed on the bases 41 to 43 of the reversing machine, and the concrete product. Try to leave under 30.
In the case of an article curved in an arc shape like the concrete product 30 shown in the figure, as shown in the figure, by basically supporting the three points on the left and right and the center with the bases 41 to 43, the product is stable without falling down. The standing state can be maintained.

Next, as shown in FIG. 8, the other hanging portions 121b of the lifting belts 12A and 12B drawn forward are attached to the separate lifting tools 112b and 112d provided on the horizontal frame 11, thereby lifting the lifting belts. The belt is attached to the concrete product 30 in a state where the belt is folded in a U shape at a substantially central portion.
Since the mounting position is a characteristic of the load handling method according to the present invention, this point will be described with reference to FIG.
FIG. 9 is a schematic view of the state in which the lifting belts 12A and 12B are attached to the concrete product 30 curved in an arc shape as shown in FIG.
As shown in the drawing, in the present invention, the two lifting belts 12A and 12B are arranged so that the center of gravity G of the concrete product is located in the region of the width W connecting the portions where the curved concrete product 30 is lifted. The mounting positions of 12A and 12B are adjusted.
By adjusting the mounting position of the lifting belt in this way, the concrete product 30 becomes equivalent to the state where the center of gravity G is supported, and it does not fall down by its own weight on either the inner peripheral surface side or the outer peripheral surface side. Disappear. Therefore, it is not necessary to tie the concrete product and the lifting belt firmly with another rope or the like, and it is curved in a stable state with only two lifting belts 12A and 12B that are simply folded back in a U shape. It is possible to lift and transport the concrete product.
That is, as described above, the center of gravity G of the concrete product 30 is located in the region of the width W, so that the concrete product maintains its standing state by its own weight, and if its overturning moment does not occur, only its own weight is sufficient. It is independent.
In order to prevent the adjustment work of the position where the lifting belt is attached from being troublesome, the belt hanging position may be set on the normal line of the curved surface of the product. That is, as shown in FIG. 9, when the direction in which the lifting belts 12A and 12B are hung is not the direction of the axial direction T of the fork claw but the center of curvature of the concrete product is O, the normal belt R is offset by an angle α. The direction is set. By doing so, if the center O of the concrete product and the center line of the left and right fork claws do not greatly deviate, the product will naturally fit in the desired position, and some misalignment will occur when the actual lifting operation is performed. Will come into the lifting center of gravity and be kept in a self-supporting position.
Therefore, when the present invention is used, it is not necessary to use a large crane or the like, which improves work efficiency and helps to save costs.

  The concrete product 30 fitted with the two lifting belts 12A and 12B as described above can be lifted to a desired height as shown in FIG. 10 by pulling up the fork mounting frame 25 along the mast 23 of the forklift 20. Therefore, the forklift can be run in that state, and the concrete product can be transported in a stable state to a desired place.

In addition, this invention is not limited to the said Example, For example, the horizontal frame 11 does not necessarily need to utilize an H-shaped steel material, and also has lifting tools 112a-112d and lifting belts 12A and 12B. As described above, the configuration of the hanging portions 121a and 121b can also be in other forms. Therefore, the present invention is within the technical scope of the claims, and the person skilled in the art will understand from the above description. All modifications that can be easily conceived are included.

As described above in detail, the present invention uses a horizontal frame attached to a fork claw of a forklift and a lifting belt attached to the horizontal frame to position the lifting belt on the concrete product when lifting a curved concrete product. Is limited to a specific position defined in the present invention, so that the concrete product is prevented from falling down and is kept in a stable position by its own weight, so that it is curved as described above without using a large crane or the like. It is possible to provide an attachment for a forklift capable of lifting and transporting a concrete product in a stable state, and a method for stably lifting and transporting a curved concrete product using the attachment.
The attachment according to the present invention can also be used as an attachment for a crane.

DESCRIPTION OF SYMBOLS 10 Forklift attachment 11 Lateral frame 111 Frame part 111a, 111b made of H-shaped steel material Fork claw insertion hole 112a-112d Lifting tool 113 Handle 114 Fall-off prevention pin 12A, 12B Lifting belt 121a, 121b Hanging part 122 Ring 123 Wire rope 124 Cover cloth 20 Forklift 21 Car body 22 Driver's seat 23 Mast 24 Roller chain 25 Fork mounting frame 26a, 26b Fork claw 261 Pin hole 30 Curved concrete product 30a Inner peripheral surface 30b Outer peripheral surface 30c Upper surface 30d Lower surface 30e Bus bar 41-43 Base G Center of gravity

Claims (3)

A horizontal frame attached in a form that spans between the left and right fork claws of the forklift,
It has a hanging part that is detachably attached to the horizontal frame at both ends, and is folded back into a U-shape at a substantially central part when used, and at that folded part, a curved concrete product as a lifting object is lifted and held. Two lifting belts,
Wherein the two lifting the hooking parts at both ends of the belt, is composed of a hanging member provided in at least two places on the transverse frame to removably retain,
The horizontal frame uses an H-shaped steel material composed of a web portion and a pair of flange portions provided on both sides of the web portion, with the web portion side in a horizontal state, and is positioned below the web portion side and A forklift attachment for handling a curved concrete product , wherein a fork claw insertion hole for inserting the fork claw is provided on each flange side . The installation position of the lifting tool provided on each flange portion is a position offset by an angle α on the normal line R, where O is the center of curvature of the curved concrete product. Attachment for forklift for handling curved concrete products as described in 1 . A forklift equipped with the forklift attachment according to claim 1 or 2 is a method for lifting and transporting a curved concrete product having a part of a curved surface having a substantially cylindrical inner peripheral surface and outer peripheral surface,
Attaching the two left and right fork claws of the forklift to the insertion hole provided in the horizontal frame so as to hang and thereby integrating the horizontal frame and the left and right fork claws;
Holding the curved concrete product in an upright state such that a generatrix of the substantially cylindrical curved surface is substantially vertical;
Attaching one hanging portion of each of the two lifting belts to separate lifting tools on the lateral frame attached to the fork claws of a forklift;
By passing the other hanging portion of each of the two lifting belts under the concrete product held in the standing state and attaching them to separate lifting tools provided on a horizontal frame, the lifting belt is substantially omitted. It is attached to the concrete product in a state of being folded in a U-shape at the center, and the center of gravity of the concrete product is located within the width region connecting the locations where the two lifting belts lift the concrete product. Adjusting so that,
Raising the fork of the forklift to lift the concrete product to a desired height with the two lifting belts, and transporting the concrete product to a desired location by running the forklift in that state;
A method for lifting and transporting a curved concrete product, characterized by comprising:

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