JPS6048326B2 - Equipment that continuously produces plate-shaped foam - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for continuously producing a plate-shaped foam, and more specifically, the present invention relates to an apparatus for continuously producing a plate-shaped foam, and more particularly, it relates to an apparatus for continuously producing a plate-shaped foam, and more specifically, a plate-shaped molded body made of a thermoplastic resin and having the property of being foamable when heated. The present invention relates to an apparatus suitable for use in continuously forming a sheet-shaped foam from a raw material.

Various proposals have been made in the past as an apparatus for manufacturing a plate-shaped foam by heating and foaming a plate-shaped molded body made of a thermoplastic resin such as polyethylene and having the property of being able to foam when heated, that is, having the so-called foaming ability. There is.

For example, a so-called horizontal type is shown in Japanese Patent Publication No. 43-22674 and Japanese Patent Publication No. 47-2426, in which foaming is performed by preheating and heating a plate-shaped molded product while continuously transporting it in the horizontal direction. Foaming devices are known.

However, although the apparatus disclosed in the above-mentioned publication may perform the intended function as an apparatus for continuously manufacturing plate-shaped molded bodies, it has the following drawbacks. In other words, since the means for supporting the plate-shaped molded body in the preheating chamber for preheating the plate-shaped molded body having foaming ability is a jet of air or an endless belt, the preheating zone is extended in the horizontal direction. However, the scale of the apparatus must become large, and the above-mentioned method may cause the plate-shaped molded product to meander when being transferred.

Furthermore, when preheating a plate-shaped molded product while supporting it with a jet of air, it is difficult to adjust the delicate pressure of the jet of air, making it difficult to provide stable support. The belt may loosen or stretch, making it difficult to provide stable support.

The present invention was made in order to eliminate the drawbacks of the conventional foaming apparatus as described above, and it can be installed in a relatively narrow place and can be transferred without causing meandering to the plate-shaped molded product. It is an object of the present invention to provide an apparatus which can smoothly produce a foam by using a supporting means that does not stretch or relax.

The present invention provides an apparatus for continuously supplying a plate-shaped molded body, a preheating chamber, a heating foaming chamber separated from the preheating chamber and having a higher temperature than the preheating chamber, and a device for continuously drawing the plate-shaped foamed body. A cylindrical rotating body whose rotational axis is orthogonal to the moving direction of the plate-shaped molded body is provided in the preheating chamber, and a surface of the rotating body is The rotating body is subjected to mold release treatment, and the diameter of the rotating body is such that the length of its semicircumference is approximately equal to the distance required to raise the plate-shaped molded body from room temperature to around the foaming start temperature. The gist of this invention is an apparatus for continuously manufacturing a plate-shaped foam body. In producing a plate-shaped foam by the apparatus of the present invention, the supplied plate-shaped molded body is, as mentioned above, a thermoplastic resin plate-shaped molded body having foaming ability. A plate-shaped molded body made from a thermoplastic resin that has the property of being softened and then foaming as the foaming agent it contains decomposes, and the plate-shaped body can also be referred to as a sheet-shaped or film-shaped body. It also includes shape.

There are no restrictions on the dimensions of the molded body, such as its wall thickness, length, width, etc., but dimensions that are normally employed are preferably used. Further, the means for producing the above-mentioned molded body is not particularly limited, and it may be produced by extrusion molding or the like, and a continuous elongated body is particularly preferable.

As thermoplastic resins, various thermoplastic copolymer resins are used, including resins such as polyethylene, polypropylene, and polyvinyl chloride, as well as ethylene-based resins such as ethylene-vinyl chloride copolymers and ethylene-vinyl acetate copolymers. It's fine. Further, the resin may be crosslinked in advance, and for example, plate-shaped molded products made from polyethylene that has been irradiated with electron beams can also be used. It is a plate-shaped molded product that undergoes crosslinking during foaming. Examples of the above-mentioned molded product include a polyethylene molded product containing an organic peroxide, or a composition consisting of polyethylene bound to an alkoxysilane and a silanol condensation catalyst (as described in Japanese Patent Publication No. 1711/1982). A molded body made from a composition) can be mentioned.

It goes without saying that the above-mentioned thermoplastic resin plate-like molded product having foaming ability may contain a foaming aid, a pigment, etc., as necessary, in addition to the foaming agent.

Next, in order to explain the present invention more specifically, the present invention will be explained in detail together with its usage mode with reference to the drawings showing embodiments of the present invention.

Although FIGS. 1 and 2 are longitudinal sectional views showing different embodiments of the apparatus of the present invention, the numbers assigned in the figures are common to both.

In the figure, reference numeral 1 denotes a pair of supply rolls, which have the function of continuously introducing a plate-shaped molded body 5 having a foaming ability into a subsequent device by rotation.

2 is a preheating chamber, 3 is a heating and foaming chamber, and a pair of take-up rolls 4 for taking off the plate-shaped foam 50 are provided at the final stage.

Although the apparatus of the present invention is provided with the supply apparatus 1, the preheating chamber 2, the heating and foaming chamber 3, and the taking-off apparatus 4 in this order as described above, the arrangement of each apparatus is not particularly limited, and for example, as shown in FIG. As shown in FIG. 2, the four types of devices described above may be arranged horizontally, or the heating and foaming chamber 3 may be arranged vertically as shown in FIG.

Further, in the case where the heating foaming chamber 3 is arranged vertically as described above, in addition to arranging it as shown in FIG. It is also possible to have the device collected from the customer.

A cylindrical rotating body 7 is provided in the preheating chamber 2, and the rotation axis 71 of the rotating body 7 is parallel to the rotation axis of the supply roll 1 as shown in the figure.

That is, the cylindrical rotary body 7 is installed in the preheating chamber 3 so that the rotation axis 71 of the rotary body 7 is perpendicular to the direction in which the plate-shaped molded body 5 moves (indicated by the arrow 10). The cylindrical rotating body 7 may be a solid body, but in view of weight reduction and the provision of other equipment inside, it is preferably a hollow body. Regarding the material, it is preferable to use a metal plate or a metal net in view of the influence of heat in the preheating chamber 3, but the material is not limited to these, and other materials such as wood or ceramics may also be used. is also available. The length of the rotating body 7 is preferably made slightly larger than the width of the plate-shaped molded body 5 to be foamed, and its diameter is such that the distance required to raise the plate-shaped molded body 5 from room temperature to around the foaming start temperature is selected. The diameter is set to be approximately equal to the semicircumference of the rotating body 7. The above-mentioned distance is determined by the temperature in the preheating chamber 3, the feeding rate of the plate-shaped molded body 5, the wall thickness of the molded body 5, and the type of resin. Also, rotating body 7
The rotational speed of is adjusted such that the circumferential speed of its outer surface matches the feeding speed of the feeding device 1. The plate-shaped molded body 5 thus supplied is transferred while being placed on the surface of the rotating body 7, and during this time is heated and preheated by the heat sources 62 and 67. As the heat sources 62 and 67, various means such as electric heaters, infrared lamps, hot air blowers, etc. can be employed. The heat source 67 is provided within the rotating body 7, and in addition to the above-mentioned means, a heated heat medium may be circulated within the rotating body 7. The temperature when preheating the plate-shaped molded body 5 in the preheating chamber 2,
In other words, in the method of using the apparatus of the present invention, the temperature is set at such a temperature that the molded body 5 does not significantly foam.
It is best to preheat to a temperature just before foaming starts. The temperature can be maintained by adjusting the heat sources 62, 67, the feeding rate of the molded body 5, etc. The plate-shaped molded body 5 that has been preheated in the preheating chamber 2 as described above is brought into a state in which the resin has sufficient viscoelasticity to be crosslinked or foamed. For this reason, the molded body 5 may soften in the preheating chamber 2 and may stick to the surface of the rotating body 7 that is placed in contact with it, so the surface of the rotating body 7 may be coated or coated with Teflon or silicone oil. By doing so, the process is performed to improve mold release properties. Furthermore, it is preferable to make the rotating body 7 from a metal net-like body as described above, since the contact area with the molded body 5 will be reduced and the fear of the above-mentioned adhesion can be reduced.
A preheating chamber 3 is provided next to the preheating chamber 2;
As mentioned above, it can be arranged either horizontally or vertically, but if it is arranged horizontally as shown in Fig. There is a need to. However, when the heating and foaming chamber 3 is arranged in the vertical direction as shown in FIG. can be supported. A heater 63 is also provided in the heating and foaming chamber 3, and the heating means may be the same as that provided in the preheating chamber 2. The amount of heat is greater than that in preheating chamber 2,
Therefore, the heater 63 is used to make the indoor temperature higher.
The type, number, and location of installation can be determined as appropriate. The molded body 5 supplied from the preheating chamber 2 is heated to a temperature higher than the foaming temperature in the heating and foaming chamber 3, and at this stage is formed into a plate-shaped foamed body 50, which is continuously taken as a product by the taking-off device 4.
Note that 30 indicates an outlet of the plate-shaped foam 50. Similarly, preheating chamber 2
An inlet 20 for the plate-shaped molded body 5 is provided in the. When the heating and foaming chamber 3 is arranged horizontally, the foam plate 50 is usually sticky at first, so in order to support the foam plate 50, as shown in FIG. Preferably, this is carried out by means of an air jet from the air jet device 8.

Further, it is preferable to separate the two chambers by a partition wall 23 so that the temperature in the heating and foaming chamber 3 and the temperature in the preheating chamber 2 do not interfere with each other.

The apparatus of the present invention has the structure described above, and has the following advantages when producing a foam using the apparatus. In other words, a cylindrical rotating body is provided in the preheating chamber, and the rotating axis of the rotating body is arranged perpendicular to the moving direction of the plate-shaped molded body, and the surface of the rotating body is subjected to mold release treatment. The diameter of the rotating body is such that the length of its semicircumference is approximately equal to the distance required to raise the plate-shaped molded body from room temperature to around the foaming start temperature. The plate-shaped molded body is transferred while being placed on the rotating body without sticking to the surface thereof, and is effectively preheated by contacting the rotating body.

Furthermore, since the rotating body is cylindrical during the above-mentioned transfer, the plate-like object can be transferred smoothly without meandering during the movement unlike a belt conveyor. In addition, since the preheating chamber and the heating and foaming chamber are separated and the heating and foaming chamber is heated to a higher temperature than the preheating chamber, heating can be performed without mutual interference, and uniform preheating and heating and foaming can be performed. The commercial value of the resulting foam is not impaired. In addition, unlike a belt conveyor, the cylindrical rotating body does not stretch or relax, so it can withstand long-term use and allows continuous production of foam. Furthermore, by incorporating a cylindrical rotating body, the horizontal length of the preheating chamber can be shortened compared to a belt conveyor or an air jet device, and the scale of the device can be reduced. Therefore, the device can be installed even in a narrow site, making it economical. In the present invention, if the heating and foaming chamber is arranged in a vertical direction, it is more convenient because there is no need to install a support device inside the heating and foaming chamber.

[Brief explanation of drawings]

1 and 2 are longitudinal sectional views showing an embodiment of the apparatus of the present invention, and the numbers of the main parts in the figures are as follows. 1... Supply device, 2... Preheating chamber, 3
... Heating and foaming chamber, 4 ... Taking device, 7
......Cylindrical rotating body, 5...Plate-shaped molded body, 50...Plate-shaped foam, 62, 67, 63
······Heater.

Claims (1)

[Claims] 1. A device for continuously supplying a plate-shaped molded body, a preheating chamber,
a heating foaming chamber having a higher temperature than the preheating chamber and separated from the preheating chamber;
A device for continuously taking up the plate-shaped foam is provided in this order, and the preheating chamber is provided with a cylindrical rotating body whose rotational axis is perpendicular to the moving direction of the plate-shaped molded body. The surface of the rotating body is subjected to mold release treatment, and the diameter of the rotating body is determined by the length of its semicircle and the distance required to raise the plate-shaped molded body from room temperature to around the foaming start temperature. 1. An apparatus for continuously manufacturing a plate-shaped foam, characterized in that the dimensions are such that the dimensions are substantially equal. 2. The device according to claim 1, wherein the surface of the cylindrical rotating body is made of a mesh body. 3. The device according to claim 1 or 2, wherein the cylindrical rotating body has a heater inside. 4. The apparatus according to claim 1, 2 or 3, wherein the heating and foaming chamber is installed vertically. 5. The apparatus according to claim 1, 2, 3, or 4, wherein the heating and foaming chamber has a transfer device.