JPH05286017A - Method and device for manufacturing synthetic resin pallet - Google Patents

Abstract

PURPOSE:To manufacture a pallet for mounting articles continuously, efficiently and at low cost by extruding synthetic resin. CONSTITUTION:In an extrusion molding machine A for synthetic resin with a mold 2 wherein frame-like extruding ports are disposed in a row, a take-off molding device B which moves vertically opposed molds 9'', 10'', disposed adjacent to each other, in a product-take-off direction is provided to extrude synthetic resin into a hollow board-like shape wherein a plurality of square cylinders are disposed parallelly, and said extruded board-like item is drawn out, while recesses are being formed on said item, so that pallets comprising synthetic resin are formed continuously.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for manufacturing a pallet for loading and unloading articles, which is used when moving or storing articles by a lift.

[0002]

2. Description of the Related Art Conventionally, a pallet has been manufactured by assembling a plurality of plate members 30 in the shape of a cage as shown in FIG. However, wooden pallets are apt to rot if left outdoors in the field such as piled up, and have poor durability. In addition, since they require a lot of sturdy and strong wood, they are not desirable from the viewpoint of forest resource protection. There wasn't. Further, it requires labor for assembling, and plate materials of different sizes have to be prepared according to the size of the pallet to be manufactured, resulting in poor productivity. Therefore, a synthetic resin pallet made from a synthetic resin material, which is an industrial waste that does not rot and is difficult to dispose, has been devised. This synthetic resin pallet was manufactured one by one by forming an insertion port of a fork in a side surface by an injection molding method in which a molten synthetic resin is injected into a mold of a predetermined shape.

[0003]

In the production of the synthetic resin pallets by the above-mentioned conventional injection method, since they are molded one by one using a mold, the productivity is poor and a plurality of pallets are produced depending on the size of the pallet. There is a problem that a mold has to be prepared, equipment cost increases, and it takes time to change the size. Further, this manufacturing method has a problem that it is difficult to embed a core material such as metal for reinforcement, and it is not possible to cope with the strength improvement of the synthetic resin pallet.

[0004]

According to the present invention, there is provided a synthetic resin extrusion molding machine in which a die having a shape in which a frame-shaped extrusion port is arranged at the tip of the extruder is attached, and the extrusion molding machine is connected to the extrusion molding machine. , A take-up molding machine that moves the pair of upper and lower pressing dies in the take-up direction of the product in a state where they are close to each other, and a cutting machine that cuts the plate-shaped synthetic resin sent from the take-up molding machine to a predetermined size. Using the synthetic resin pallet manufacturing equipment equipped with it, a plurality of rectangular cylinders were taken out while forming recesses on the surface of the synthetic resin extruded in the shape of a hollow plate, and at the same time natural cooling or forced cooling was performed. It was decided that a substantially rectangular parallelepiped synthetic resin pallet would be continuously formed by cutting the synthetic resin pallet.

[0005]

In the extrusion molding machine having a die having a frame-shaped extrusion port arranged in a row, a core material is embedded as necessary to extrude a synthetic resin into a hollow plate shape in which a plurality of square tubes are arranged in parallel. In addition, the take-up molding machine having the pressing die projecting at a predetermined position takes in the plate-like synthetic resin extruded from the extrusion molding machine, and at the same time, the recess for improving the rigidity of the pallet. To act as.

[0006]

1 is a simplified plan view showing an embodiment of the synthetic resin pallet manufacturing apparatus of the present invention, and FIG. 2 is a right side view thereof. As shown in the figure, the synthetic resin pallet manufacturing apparatus of the present invention comprises a synthetic resin extrusion molding machine A, a take-up molding machine B, and a cutting machine C, which are arranged in a line. Synthetic resin extruders 1 and 1 are attached to the left and right of a mold 2 having outlets (not shown) arranged in a row. Further, the take-up molding machine B is constructed such that the columns 5, 6 are erected on the base 4 and the frames 7, 8 are provided.
And a crawler belt 9 formed by connecting a plate-shaped body 9 ′ made of metal, hard rubber or the like between drive wheels 11 and driven wheels 12 attached to both ends of the frame 7, Similarly, a crawler belt 10 formed by connecting similar plate-shaped bodies 10 ′ between the drive wheels 13 and the driven wheels 14 attached to both ends of the frame 8 is wound, and both crawler belts 9 and 10 are vertically moved. The crawler belts 9 and 10 are provided with pressing dies 9 "and 10" having a substantially trapezoidal cross section at predetermined intervals. The drive wheels 11 and 13 are connected to the AC servo motor 2 via a power transmission mechanism and a speed reducer 29 (not shown).
8 and are synchronized with each other so as to rotate in opposite directions. Further, the cutting machine C is provided with a rail 16 on the base 15 in a direction orthogonal to the product conveying direction.
A cutter 17 is attached to the so that it can travel freely.
Reference numeral 8 is a guide for guiding the formed pallet, and 19 is a roller for conveying the completed pallet.

In the drawings, reference numeral 3 is an extrusion molding machine A.
1. A temperature controller for adjusting the temperature of the plate-shaped synthetic resin extruded from the mold 2 to a temperature suitable for the take-up molding, and D is a roller conveyor that conveys the completed pallet.

Next, a method of manufacturing a synthetic resin pallet by the pallet manufacturing apparatus having the above-described structure will be described. First, the extruders 1 mounted on both sides of the mold 2 are used to synthesize the thermoplastic mold in the mold 2. When the resin is heated and extruded,
The plasticized synthetic resin is extruded from a frame-shaped extrusion port (not shown) provided on one side of the mold 2 into a shape in which square tubes are arranged as shown in FIG. In FIG. 5, reference numeral b indicates a core material such as metal or fiber embedded in the synthetic resin a in order to improve the strength, and the core material b is a conventionally known means at the time of the above-mentioned extrusion molding. It is embedded and extruded together with the synthetic resin a. The hollow plate-shaped synthetic resin a extruded in this way is then fed between the crawler belts 9 and 10 of the take-up molding machine B, and the upper and lower crawler belts 9 which rotate in synchronization therewith,
It is sandwiched between 10 and taken up, but at that time, the track 9,
Hollow portions c are crushed and crushed at predetermined intervals by pressing dies 9 "and 10" provided in 10, and concave portions d are formed on the surface as shown in FIG. Be done. At this time, in order to prevent the crushing of the synthetic resin a around the pressing dies 9 ", 10", the surface thereof is sucked from the front and back by a suction mechanism (not shown) or a blower mechanism (not shown) is used for the hollow portion c. We will press in the air. Thereafter, the plate-shaped synthetic resin a described above is sent to the cutting machine C, where the cutter 17 travels on the rail 16 at predetermined intervals, and is cooled and solidified while passing through the take-up molding machine B. A plate-shaped synthetic resin a is laterally cut to manufacture a synthetic resin pallet having a desired size. Then, the completed pallet is conveyed by the roller conveyor D continuously provided and collected in a stacker (not shown). Thus, according to the method of the present invention, the synthetic resin pallets are continuously manufactured.

FIGS. 3 and 4 show another embodiment of the take-up molding machine. In this example, instead of the above-mentioned endlessly rotating crawler belt, means for moving up and down the pressing die and means for horizontally moving the pressing die. It was decided to drive using and. Figure 3
Describing the configuration based on FIG. 2, reference numeral 20 denotes an air cylinder that is a means for moving up and down the pressing die, and the air cylinders 21 are vertically opposed to each other and have a substantially trapezoidal cross section at predetermined intervals.
Are attached above and below a frame 23 that holds the pressing mold 21 in accordance with the protruding pressing mold 21. Again 2
Reference numeral 4 denotes a spiral rod which is a means for moving the pressing die in the horizontal direction, and is engaged with the lower end of the frame body 23 to allow the motor 2
It is adapted to be rotationally driven at 5. Reference numeral 26 denotes a belt that conveys the plate-shaped synthetic resin extruded from the extrusion molding machine, and is driven by the motor 22 in synchronization with the extrusion speed of the synthetic resin.

In the take-up molding machine B'using the linear driving means constructed as described above, when the plate-like synthetic resin is first supplied from the extrusion molding machine, the air cylinder 20 causes the upper and lower pressing molds to be pressed. 21 are moved toward each other so that the synthetic resin is sandwiched between the pressing dies 21, and then the frame 23 to which the pressing dies 21 are attached by the motor 25 is synchronized with the conveying speed of the synthetic resin. When moved, the convex portion 21 'of the pressing mold 21 is pressed into the surface of the synthetic resin having plasticity so as to crush the hollow portion of the synthetic resin during this movement to form a concave portion. At this time, as in the case of the above-described embodiment, the surface of the synthetic resin is sucked by a suction mechanism (not shown) or air is forced into the hollow portion of the synthetic resin, so that the convex portion of the pressing die is pressed. The surrounding area should be prevented from being immersed. The belt 26 supporting the synthetic resin is also driven by the motor 22 in synchronization. Then, when the frame body 23 moves to the end of the spiral rod 24, this time the air cylinder 20 separates the pressing die 21 from the surface of the synthetic resin, and the motor 2
The frame 23 is returned to the initial position by rotating 5 in the reverse direction, and the same operation is repeated. In this way, in the take-up molding machine B'according to the second embodiment, the operation of pulling the plate-shaped synthetic resin continuously fed while forming the concave portion on the surface is intermittently performed.

Regarding the fluctuation of the take-up force when the pressing die 21 is returned, as shown by the two-dot chain line in FIG.
A take-up roller 27 having a convex portion 27 'facing the belt 26 is provided at the rear end of the belt 6, or a take-up molding machine B'is separately provided with a take-up dedicated machine (not shown). I will.

In this embodiment, an air cylinder is used to move the pressing die up and down, and a spiral rod is used to horizontally move the frame to which the pressing die is attached. Needless to say, the mold may be driven linearly, and other means such as hydraulic pressure or electromagnetic solenoid may be used as the driving means. Further, in the embodiment, an example in which three recesses are formed in the lateral direction of the pallet has been shown, but the recesses are appropriately formed according to the size of the pallet except for the fork insertion opening (indicated by reference character c'in FIG. 6). It may be provided, and the number and location thereof are arbitrary. Furthermore, in the examples, an example in which the core material is embedded in the outer flat surface portion of the pallet is shown, but the location where the core material is embedded is arbitrary, and by adding an additive to the synthetic resin, sufficient strength is imparted to the pallet. When obtained, the core material does not necessarily have to be embedded.

[0013]

As described above, according to the present invention, since the pallets made of synthetic resin are continuously formed, no manpower is required.
The pallet can be efficiently manufactured, and the size can be easily changed by cutting it at any place, which improves the productivity. Since the concave portion is formed on the surface, the rigidity of the pallet is improved and the placed article is less likely to slip.
Since the core material can be embedded and formed, the strength of the pallet can be easily improved. Since it is formed by reusing a synthetic resin material that is difficult to treat as waste, it can be manufactured at low cost, is resistant to decay, and has excellent durability. In addition, it helps prevent environmental destruction and protects forest resources. Further, in the take-up molding machine using the crawler belts shown as the first embodiment, since the synthetic resin can be continuously taken over only by synchronously rotating the upper and lower crawler belts,
The work can be performed smoothly without requiring a complicated control mechanism, and the molding speed can be easily changed. Further, in the take-up molding machine having the reciprocating drive means shown as the second embodiment, it is easy to attach the suction means and the cooling means to the pressing die, and when the cooling means is provided, it is more efficient. It is possible to continuously manufacture highly accurate synthetic resin pallets, and by forming desired concaves and convexes on the pressing mold in places other than the convexes, it is possible to form concaves on the surface of the pallet and at the same time prevent desired slippage. It has many excellent effects that can be applied.

[Brief description of drawings]

FIG. 1 is a simplified plan view showing an embodiment of the device of the present invention.

FIG. 2 is a right side view of FIG.

FIG. 3 is a side view showing another embodiment of the take-up molding machine.

FIG. 4 is a plan view of FIG.

FIG. 5 is a perspective view of the plate-shaped synthetic resin extruded from the extruder.

FIG. 6 is a perspective view showing a molding example of a synthetic resin pallet.

FIG. 7 is a perspective view showing a conventional example of a pallet.

[Explanation of symbols]

 A Extrusion Molding Machine B Bending Molding Machine C Cutting Machine 1 Extruder 2 Mold 8,9 Crawler Track 8 ", 9", 21 Pressing Mold 20 Air Cylinder 24 Spiral Rod

Claims (4)

[Claims] 1. An extruder is used to extrude a synthetic resin into a hollow plate shape in which a plurality of square cylinders are arranged in parallel, and the synthetic resin is sandwiched between a pair of upper and lower pressing dies while being sucked from above and below or having an increased internal pressure. A method for producing a synthetic resin pallet, which comprises pulling out and continuously forming a synthetic resin pallet having recesses at predetermined intervals. 2. A synthetic resin extrusion molding machine comprising a die having a frame-shaped extrusion opening arranged in a row at the tip of the extruder,
A take-up molding machine that is connected to the extrusion molding machine and moves a pair of upper and lower pressing dies in a product take-up direction in a state where they are close to each other, and a plate-shaped synthetic resin sent from the take-up molding machine to a predetermined length. A device for manufacturing synthetic resin pallets, which is equipped with a cutting machine that cuts at a length. 3. A crawler belt formed by connecting plate-like bodies such as metal or hard rubber having a pressing die protruding from the take-up molding machine is arranged vertically. Manufacturing equipment for synthetic resin pallets. 4. The take-up molding machine comprises a means for driving a pair of upper and lower pressing dies in a contacting / separating direction, and a means for moving the pressing dies in a horizontal direction. The synthetic resin pallet manufacturing apparatus described.