JPH08142200A - Manufacture of loading pallet - Google Patents

Abstract

PURPOSE: To easily obtain a low-cost loading pallet of synthetic resin having a light weight and high durability in a short time. CONSTITUTION: A plurality of legs 3 are disposed in two directions perpendicular in the same plane, deck boards 1, 2 are provided at both sides of the legs 3, and coupling parts 4 are opposed to the ends of the legs 3, heating plates 17a, 18a are inserted between the legs 3 and the board 1 of the one end side and between the legs 3 and the board 2 of the other end, the adjacent ones are brought into close contact, and both the ends of the legs 3 and the coupling parts of the opposed boards 1, 2 are heated and fused by heating plates. Then, the contact is released, the plates are drawn, the legs 3 and the boards 1, 2 of both the ends are press bonded, the ends of the legs 3 and the coupled parts 4 of the boards 1, 2 are fusion bonded, and coupled, thereby manufacturing the loading pallet made of synthetic resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a cargo pallet for manufacturing a cargo pallet used for cargo work using a forklift.

[0002]

[Prior Art] Japanese Patent Publication No. Sho 53 as a conventional pallet for cargo handling.
There is one described in Japanese Patent Publication No. 36220. As shown in FIG. 11, this conventional example includes a pair of upper and lower deck boards a and b made of synthetic resin, and a plurality of synthetic resin pipe legs c that keep them in parallel with each other at a predetermined interval. It is configured. On the back surface of each deck board a, b, there is formed a fitting protrusion d that fits to the end of the leg c, and the end of each leg c is fitted to each of these fitting protrusions d. In this state, a pair of upper and lower deck boards a and b and a plurality of legs c are integrally combined by using about three sets of bolts and nuts e for each leg c.

[0003]

By the way, a large bending moment may act on the pair of upper and lower deck boards a and b depending on the usage conditions. At this time, in order to prevent permanent deformation between the denki boards a and b and the leg c due to relative movement, the fitting protrusion d and the leg c are increased in fitting rigidity and the bolt is -It is necessary to increase the tightening force of the nut e so that the leg c is strongly pinched and held between the upper and lower deck boards a and b. However, in order to improve the fitting rigidity, there is a problem of weight increase due to thickening of the resin portion and a problem of strength imbalance with other portions due to partial rigidity increase. To increase the power, a synthetic resin deck board a,
Since there is a limit due to insufficient strength of b, in the conventional example, permanent deformation easily occurs due to the bending moment.

In the above conventional example, the bolt / nut e
It is necessary to provide a large number of holes through which the deck boards a and b are inserted, and since these holes weaken the bonding strength of the deck boards a and b, there is a problem in durability.

Further, at the time of assembling the pallet, it is necessary to insert the bolts / nuts e at a large number of places and to perform the respective fastening work, and also to adjust the fastening force of the bolts / nuts e.
Since it is necessary to prevent the rotation, there is also a problem that the manufacturing cost increases due to an increase in the number of assembly steps and an increase in component cost.

Therefore, according to the present invention, the deck board and the legs are joined together in a state similar to the case where they are integrally molded without fitting portions or fastening portions, so that a pallet for cargo handling which has no problem as in the past can be easily formed. Moreover, it is an object of the present invention to provide a method of manufacturing a cargo pallet that can be obtained in a short time at low cost.

[0007]

In order to solve the above-mentioned problems of the conventional example, the present invention arranges a plurality of synthetic resin pipe legs in two directions orthogonal to each other on the same plane. While placing a synthetic resin deck board on one end side of the, and placing a synthetic resin deck board or lower plate on the other end side, the joint with each leg is opposed to the end of each leg, Insert a heating plate between each leg and the deck board facing one end thereof, and between each leg and the deck board or lower plate facing the other end of each leg,
By bringing these adjacent parts into close contact with each other, both the end portions of the legs and the connecting parts of the deck board or the lower plate facing them are heated and melted by the heating plate, and then the close contact state is set. After unwinding and pulling out the heating plate from the insertion position, each leg and the deck board or the lower plate on one end side and the other end side of the leg body are crimped to face the end portion of each leg body and the end portion thereof. The deck board or lower plate is joined by melting and joining, and each leg and the deck board or lower plate on one end side and the other end side of the leg body are integrated to manufacture a cargo pallet. It is characterized by

[0008]

In the above-mentioned structure of the present invention, a plurality of legs made of synthetic resin pipes, a synthetic resin deck board at one end of the legs, and a synthetic resin deck board or a lower end at the other end of the legs. Since each of the plates and the ends of the legs that face each other and the connecting portions of the deck board or the lower plate that face each other are melted and pressure-bonded, the bolts and nuts, etc. There is no need for parts or work for inserting them.
Also, there is no need for fastening parts or fitting structures for joining,
All that is required is to have a well-balanced wall thickness distribution that satisfies the required strength, and it will be slimmer, lighter and cheaper than before. Moreover, it has a sufficient shape-retaining strength and can flexibly absorb and absorb external force as a whole, resulting in excellent durability.

Moreover, a plurality of legs made of synthetic resin pipes, a synthetic resin deck board at one end of the legs, and a synthetic resin deck board or lower plate at the other end of the legs are provided.
Face each other according to the positional relationship required for each connection,
Simply insert a heating plate between the leg and the deck board or bottom plate on both sides of this leg to bring the adjacent parts into close contact with each other. All of the joints of the deck board or the lower plate can be put into a molten state necessary for melting and welding all at once, and then the heating plate is pulled out from the insertion position, and each end of the leg body is pulled out. After making the connecting parts and the connecting parts face each other in the molten state, simply crimp the legs and the deck boards or lower plates on both sides, and each end of the legs facing each other in the molten state and the deck. All of the joints of the board or the lower plate can be fused at once, and the cargo handling pallet with the above characteristics can be manufactured easily and in a short time by simple work, and the product cost can be reduced. be able to.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method for manufacturing a cargo handling pallet according to the present invention will be described below with reference to the drawings.

The manufacturing method of the cargo pallet of this embodiment is as follows:
For example, a pallet for cargo handling as shown in FIGS. 6A and 7C is manufactured. As shown in the figure, this cargo handling pallet includes a pair of upper and lower deck boards 1 and 2 made of synthetic resin,
It is composed of nine legs 3 made of a synthetic resin pipe that keep them in parallel at a predetermined interval.

The deck boards 1 and 2 are made of a hard synthetic resin such as polyethylene, vinyl, ABS (a) in the figure,
It is obtained by compression molding into a shape as shown in (b), (b) and (c) of FIG. 7. Deck board 1,
In order to increase the surface resistance of No. 2, it is preferable to mix powder particles such as rubber material, wood and carbon with the hard synthetic resin. Alternatively, in order to increase the surface resistance, as shown in (a), (b) of FIG. 6 and (a), (b), (c) of FIG. The connecting portions 4 for connecting the end portions of the legs 3 are provided at the four corners of the deck boards 1 and 2, the center of each side, and the central position at nine positions. The connecting portion 4 has a short tubular shape protruding from the back surfaces of the deck boards 1 and 2, more specifically, a cylindrical shape having a small protruding amount.

The tubular coupling portion 4 may have a shape other than a cylinder, for example, a tubular shape having a rectangular cross section. Reinforcing ribs 5 are formed on the back surfaces of the deck boards 1 and 2 except the connecting portions 4. In this embodiment, the grid-like reinforcing ribs 5 having a relatively small pitch are formed, but if the deck boards 1 and 2 can be improved in rigidity, other shapes of reinforcing ribs may be formed. Good.

The leg 3 is made of a hard synthetic resin such as polyethylene, vinyl, ABS, etc., and is made of a material shown in FIGS.
(A) and (b) are extruded and machined into a predetermined size to finish the end face. The leg body 3 has a cross-sectional shape that matches the joint portion 4 of the deck boards 1 and 2, and is formed in a cylindrical shape in the case of the present embodiment. The upper and lower end surfaces of the leg body 3 are butt surfaces 3a that are closely butted to the butt surface 4a of the coupling portion 4. These abutting surfaces 3a, 4a are formed as flat surfaces. The leg body 3 may not have a tubular shape in some cases. A groove shape or a simple block shape can be used, and the shape of the coupling portion 4 is also adapted to this.

The cargo handling pallet is shown in FIGS. 7 (a), 7 (b), and 7 (c) with the respective connecting portions 4 of the pair of upper and lower deck boards 1 and 2 and the end portions of the nine legs 3. As shown, the abutting surfaces 3a and 4a are abutted against each other, and are fused and integrally joined to complete the process. In addition, in FIG. 1D, FIG. 6A, and FIG. 7C, the fusion-bonded portion integrally connected is indicated by a symbol P.

The heating conditions for this fusion welding are well known and will not be described. Further, in order to increase the bonding strength by fusion bonding, the bonding portions 4 of the deck boards 1 and 2 can be formed flush with the back surfaces of the deck boards 1 and 2.

In this embodiment, the deck boards 1 and 2 as described above and the nine legs 3 are integrally joined by fusion welding,
To manufacture the cargo handling pallet shown in FIG. 6 (a), first, the nine legs 3 are arranged in two directions orthogonal to each other on the same plane, in this embodiment, three rows vertically and horizontally. Position it.

For this purpose, for example, it is preferable to use a supporting mechanism 11 as shown in FIGS. This support mechanism 1
1 has three pairs of chucks 12 in which the nine legs 3 are provided so as to correspond to a row aligned in one direction, for example, a lateral direction. Each chuck 12 is composed of a pair of chuck pieces 12a and 12b having a length capable of simultaneously gripping three legs 3 arranged in a row facing each other at a required interval, and the chuck pieces 12a and 12b are moved in parallel. By opening and closing, the three legs 3 can be grasped at the same time, and they can be released at the same time. Such being able to grip and release at the same time means that a plurality of legs 3 are gripped or released, one leg 3 is gripped,
This can be achieved in the same time as releasing it, which is convenient when a large number of legs 3 are subjected to coupling. This gripping and gripping release are chuck pieces 12a and 12b.
What is done by the simultaneous translations of is achieved in the shortest stroke and in the shortest time. If this is not desired, other opening / closing methods such as scissors-type opening / closing methods can be employed.

Each of the chucks 12 after the plurality of legs 3 gripped respectively are joined to the deck boards 1 and 2,
With the legs 3 connected to the deck boards 1 and 2 being released as shown in (d) of FIG. 1, as long as the legs 3 held by them are moved side by side, It is possible to freely retreat without interfering with the joined legs 3.

In this embodiment, the support mechanism 11 travels while being guided by the wheels 13 provided on the base 31 of the support mechanism 11 and the guide rails 14 on which the wheels 13 are mounted, and the chucks 12 are moved.
To the joining work position A shown in FIGS. 1 and 4 for performing the joining with the deck boards 1 and 2, or joining work position A
To the retracted position B shown in FIG. However, this advancing / retreating direction may be any direction as long as the legs 3 are lined up. However, the arrangement direction of the legs 3 gripped by each chuck 12 needs to match the advancing / retreating direction.
When the base 31 is moved back and forth, for example, as shown in FIG.
This is automatically performed by the reciprocating drive of the cord 38 which is stretched by 6 and 37 and driven by the reversible motor 35. However, it can be done manually. At the retracted position B, as shown in FIG. 4, for example, the pins 51 are used to suspend the base 11 in a required arrangement state so that it can be transferred to the support mechanism 11 which has returned to the retracted position B. It is preferable to do it.

A pair of chuck pieces 12 of each chuck 12
As shown in FIGS. 2 and 3, a and 12b are guided by a dovetail / dove groove fitting portion 32 between the inner surface of the side plate 31 of the base 31 so as to be vertically movable, and are regulated by the stopper 33 by the spring 15. If the actuator 16 such as a solenoid or a fluid cylinder is driven in the closing direction by keeping the open state, the chuck pieces 12a and 12b are closed against the spring 15 and the leg 3 is elastically moved. So that it can be held. At the portions of the chuck pieces 12a, 12b that hold the legs 3, gutter-shaped contact plates 12c are provided along both sides of the legs, so that the cylindrical legs 3 can be held stably without tilting. . Further, since the backing plate 12c serves to connect each of the grasped legs 3 to the deck boards 1 and 2 on both sides, both ends of the grasped leg 3 are sized so as to be open to both sides of the deck boards 1 and 2. . As a result, the chuck 12 that holds the leg 3 does not hinder the connection between the leg 3 and the deck boards 1 and 2.
Each chuck piece 12a, 12b is a rack 1 provided on them.
The pinions 39 meshing with 2d are interlocked so that the center between the two is always at a fixed position. As a result, the grasped leg body 3 can be centered, and after the leg body 3 and the deck boards 1 and 2 are coupled to each other, the chuck 12 causes the leg body 3 to move.
It is possible to reduce the required opening degree for retracting without interfering with.

However, the chuck 12 is the chuck piece 12
It is also possible to adopt a system in which one of a and 12b is fixed and the other is opened and closed by being brought into contact with the fixed side, and in this case, each chuck 12 is integrally moved upward or By moving the chuck piece 12 downward
The fixed side of a and 12b may be set to a predetermined grip height with respect to the leg body 3, and the other may be brought into contact with and separated from the leg body to open and close to grasp the leg body 3 and release it. In addition, after the grasped leg body 3 is used for coupling with the deck boards 1 and 2,
Conversely, by moving each chuck 12 downward or upward to return it to its original position, it becomes possible to retract to the retracted position B without interference with the legs 3 connected to the deck boards 1 and 2.

Next, the deck board 1 is arranged on one end side of each leg 3 held at the combining work position A in the arrangement state required for the connection using the support mechanism 11, and the deck board 2 is arranged on the other end side thereof. Then, the ends of the legs 3 and the connecting portions 4 of the deck boards 1 and 2 facing the ends of the legs 3 face each other in the axial direction of the legs 3, and one end of each leg 3 in this state and The ends of the legs 3 and the joints 4 are fused and welded between the deck boards 1 facing each other and between the other ends of the legs 3 and the deck board 2 facing the other ends, respectively. The heating plates 17 and 18 for heating to a molten state are inserted and withdrawn.

As shown in FIG. 1A, the heating plate 1
Insertion and withdrawal of 7 and 18 may be performed by any method from any direction. In this embodiment, as shown in FIG. 1, each of the heating plates 17 and 18 is hung by a cord 21 such as a chain, a chain or a wire, and is raised and lowered by a winding mechanism (not shown). The mechanism is simple and can be achieved without taking up a flat space.

To insert the heating plates 17 and 18 into the molten state between the end portions of the legs 3 and the connecting portions 4 of the deck boards 1 and 2 facing the end portions, the deck boards 1 on both sides are 2, and the heating plates 17 and 18 located inside of them, and the adjacent ones of the legs 3 between the heating plates 17 and 18 are brought into close contact with each other as shown in FIG. This allows the deck boards 1 on both sides to
The abutting surfaces 3a, 4a of the coupling portions 4 of 2 and the ends of the legs 3 facing each other are heated by the heating plate 17,
It is heated in contact with 18 and melted.

For this heating, the heating plates 17, 1
Although it is preferable to use a metal heating plate 8 made of a good thermal conductor such as aluminum having a sheathed heater built-in, a metal case may have a surface heater built-in. Since the joining portions 4 of the deck boards 1 and 2 and the ends of the legs 3 project from each other, the heating surfaces 17a and 18a of the heating plates 17 and 18 may be flat surfaces. However, for example, when the joint portions 4a of the deck boards 1 and 2 are flush with the back surfaces of the deck boards 1 and 2, as shown in FIG. 8, the heating surface 17a facing the joint portions 4 of the heating plates 17 and 18, 18
It is preferable that a is formed in a shape corresponding to the joint portion 4a so as to project from the surface.

After melting the joining portions 4 of the deck boards 1 and 2 and the ends of the legs 3 from their abutting surfaces 3a, 4a side, in order to fuse them, first, the above-mentioned close contact state is released. The heating plates 17 and 18 are pulled out from the insertion position, and the deck boards 1 and 2 on both sides and the legs 3 located between them are crimped as shown in FIG. The joining portions 4 of the deck boards 1 and 2 facing each other in a state can be fused to the ends of the base 11, and the deck boards 1 and 2 on both sides can be fused.
And each leg 3 located between these is integrated, and a pallet for cargo handling made of synthetic resin can be manufactured. The integration by fusion is completed when the pressure-bonded fusion-bonded portion is cooled and solidified. In order to accelerate this, it is advantageous to blow cooling air or to inject cooling water for forced cooling. However, it can be naturally cooled. It is preferable to perform such cooling in the pressure-bonded state in order to prevent displacement and defective connection.

The close contact between the deck boards 1 and 2 and the legs 3 with the heating plates 17 and 18 sandwiched therebetween and the pressure bonding between the deck boards 1 and 2 and the legs 3 with the heating plates 17 and 18 removed. It is preferable to employ the crimping mechanism 41 as shown in FIG. This crimping mechanism 41
Connects the holders 22 for holding the left and right outermost deck boards 1 and 2 to the fluid cylinder 43 on the side stand 42, and controls the advancing stroke of the fluid cylinder 43 so that the deck boards 1 on both sides are The contact state and the pressure-bonded state can be obtained between the two. The close contact and the release of the crimp are performed by the fluid cylinder 43.
Should be moved backward. The holder 22 has a large number of suction holes 24 shown in FIG. 5 connected to a suction source on the holding surface 22a, and the suction operation through the suction holes 24 sucks the deck boards 1, 2 and the like onto the holding surface 22a, The one that can be held is adopted. However, the present invention is not limited to this, and various types can be adopted. According to the holder 22 as described above, since the deck boards 1 and 2 can be adsorbed and held on the wide holding surface 22a, the holding is stable and
When the positioning pieces 25 as shown in FIGS. 1A and 5 are provided on the holding surface 22a so as to receive the corner portions of the deck boards 1 and 2 to be sucked and held from the surroundings, the deck boards 1 and 2 are It can be positioned firmly on the holding surface 22a.

During the contacting and crimping operations, if the legs 3 are held by the chucks 12 of the supporting mechanism 11 so that they can be slid slightly in the axial direction, the legs 3 can be accurately aligned and both sides can be aligned. Even if the deck boards 1 and 2 are accurately synchronized and the working distances are not equalized, the end of each leg 3 in which the close contact and the crimp are aligned in the center is heated by the heating plate 17,
It can be achieved properly while aligning on the surface of 18 or the deck boards 1, 2.

According to the manufacturing method of this embodiment described above, a plurality of legs 9 made of synthetic resin pipes and the deck boards 1 and 2 made of synthetic resin to be joined to both sides of the legs 9 are joined to each other. Since the parts are melted and pressure-bonded, the parts such as bolts and nuts and the work of inserting the parts are not required for the connection.
In addition, there is no need for extra parts or fitting structure for joining, as long as it has a balanced wall thickness distribution enough to satisfy the required strength, it will be slimmer than before, It will be lightweight and inexpensive. Moreover, the shape retention strength is sufficiently exerted, and the entire structure flexibly absorbs external force and absorbs it, resulting in excellent durability.

A plurality of legs 3 made of synthetic resin pipes
And a deck board 1 made of synthetic resin on one end side thereof and a deck board 2 made of synthetic resin on the other end side of the leg body 3 are made to face each other in a positional relationship necessary for their coupling, By inserting the heating plates 17 and 18 between the body 3 and the deck boards 1 and 2 on both sides of the body 3 and bringing the adjacent ones into close contact with each other, the end portions of the leg body 3 and the respective end portions thereof are All the joining portions 4 of the deck boards 1 and 2 on both sides facing each other can be brought into a molten state required for melting and welding all at once, and then the heating plates 17 and 18 are pulled out from the insertion position. Then, each end portion of the leg body 3 and each coupling portion 4 are made to face each other in a molten state, and then the leg body 3 and the deck boards 1 and 2 on both sides are simply crimped to face each other in a molten state. Deck board 1 with each end of leg 3 that fits
It is possible to melt and bond all of the connecting portions 4 of No. 2 at once, and it is possible to easily manufacture the cargo handling pallet having the above characteristics in a short time by a simple work, and to reduce the product cost. it can.

As a pallet for cargo handling, the deck board 1 is connected to one end of the leg 3, and the lower plate 71 common to the leg 3 in the same row as shown in FIG. 10
It is also possible to combine individual lower plates 72 for each of the legs 3 as shown in FIG. 5, and in manufacturing the cargo handling pallets shown in FIGS. 9 and 10, instead of the deck board 2,
The lower plate 71 or 72 is simply held by suction by the holder 22, and the subsequent manufacturing process can be performed in the same manner as in the above-described embodiment.

[0033]

According to the present invention, a pair of upper and lower synthetic resin deck boards or lower plates are joined by a plurality of synthetic resin pipe legs to maintain a parallel state at a predetermined interval. In order to manufacture a pallet for use in manufacturing, the above-mentioned joining is performed by melting and welding the end of each leg and each joining part of the deck board or lower plate. Is unnecessary. In addition, there is no need for fastening parts or fitting structures for joining, as long as it has a balanced wall thickness distribution that satisfies the required strength as a whole, it is slimmer and lighter than conventional products. And it becomes cheap. Moreover, while having sufficient shape retention strength, it can flexibly absorb the external force and absorb it.
It has excellent durability.

Moreover, the members to be joined are opposed to each other in a required positional relationship, and a heating plate is inserted between the legs and the deck boards or lower plates on both sides of the legs to bring the adjacent members into close contact with each other. Just by making each end of the leg,
All of the joints on both sides of the deck board facing the respective end portions can be brought into a molten state necessary for melting and welding all at once, and then the heating plate is pulled out from the insertion position. , Legs that are facing each other in a molten state simply by crimping the legs and the deck boards or lower plates on both sides after making the ends of the legs and the connecting portions face each other in a molten state. All the ends of the body and the joints of the deck board or the lower plate can be melted and welded all at once, and a pallet for cargo handling having the above characteristics can be manufactured easily and in a short time by simple work. Therefore, the product cost can be reduced.

[Brief description of drawings]

FIG. 1 is a side view showing a working state of a cargo handling pallet manufacturing apparatus and a main part according to a first embodiment of the present invention.

FIG. 2 is a front view showing a chuck portion of a support mechanism that simultaneously grips a plurality of legs of the apparatus of FIG. 1 and uses them for joining.

FIG. 3 is a plan view of a chuck portion of the support mechanism of FIG.

FIG. 4 is a front view showing the overall configuration of the support mechanism of FIG.

5 is a front view of a holder for holding a deck board and the like provided in the crimping mechanism of the apparatus of FIG.

FIG. 6 is a perspective view showing an example of a cargo pallet manufactured by the method of the present invention and a back view of a deck board used for the pallet.

7A and 7B are a side view and a cross-sectional view showing stepwise a welding operation of the cargo pallet shown in FIG.

FIG. 8 is a partial side view showing an apparatus for manufacturing a cargo pallet according to a second embodiment of the present invention.

FIG. 9 is a perspective view showing another cargo handling pallet manufactured by the method of the present invention.

FIG. 10 is a perspective view showing still another cargo handling pallet manufactured by the method of the present invention.

FIG. 11 is a cross-sectional view showing a conventional cargo handling pallet made of synthetic resin.

[Explanation of symbols]

 1, 2 Deck board 3 Legs 4 Connection part 17, 18 Heating plate 71, 72 Lower plate

Claims (1)

[Claims] 1. A plurality of synthetic resin pipe legs are arranged in two orthogonal directions on the same plane, and a synthetic resin deck board is provided at one end of the legs and a synthetic resin pipe is provided at the other end. The deck board or the lower plate of is arranged so that the joint portion with each leg body faces the end portion of each leg body, and between each leg body and the deck board facing one end thereof, and each leg body and By inserting a heating plate into each of the deck boards or lower plates facing each other at the other end, and adhering these adjacent ones to each other, both ends of the leg body and the deck boards or lower plates facing each other. Both of the joints of the heating plate are heated and melted by the heating plate, and then the close contact state is released and the heating plate is pulled out from the insertion position, and then each leg and one end side and the other end side thereof are Deck board again By crimping the lower plate,
The ends of each leg and the respective connecting portions of the deck board or lower plate facing it are fused and joined together, and each leg and the deck board or lower plate on one end side or the other end thereof A method for manufacturing a cargo pallet, characterized in that each of them is integrated to manufacture a cargo pallet.