JPS6353009B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermoplastic synthetic resin molding machine, particularly to a method for supplying chips, which are thermoplastic synthetic resin materials, to an injection molding machine for slide fastener chains made of thermoplastic synthetic resin, and improvements to the apparatus. By using a simple method and equipment, recycled chips made by shredding runners, spools, etc. cut from the molded product are continuously fed into the hopper of an injection molding machine, and a new thermoplastic compound is added thereto. To provide a method that can automatically supply resin chips, and to supply recycled chips by using simple hoppers and transfer means, without using special mixing equipment or metering equipment. and chips of the new thermoplastic synthetic resin can be automatically supplied while maintaining a substantially predetermined mixing ratio and a substantially uniform mixing state, and an opening for supplying the chips of the new thermoplastic synthetic resin The object of the present invention is to provide a material supply device in which the position of a fixed hopper can be easily adjusted, removed, etc., and the mixing ratio can be easily changed.

Generally, when molding slide fastener chains made of thermoplastic synthetic resin, the proportion of materials consumed by runners, spools, etc. reaches 40 to 60% of the total amount of material supplied to the synthetic resin molding machine. It has been proposed to return the runners, spools, etc. into new thermoplastic synthetic resin chips and completely mix them for reuse, but the structure is difficult because mixing devices, metering devices, etc. are usually used. It is complicated and requires skill to operate, and equipment costs are high. Particularly in the dry blending method, cleaning at the time of color change has the drawback of significantly lowering work efficiency.

The present invention satisfies the above-mentioned needs and eliminates the drawbacks of the conventional means by having the configurations described in claims 1, 2, and 3. That is, the method according to claim 1 involves feeding a thermoplastic synthetic resin material into a mold of a thermoplastic synthetic resin molding machine to mold a product, and shredding runners, spools, etc. separated from the product. In a material supply method for a thermoplastic synthetic resin molding machine in which recycled chips are automatically supplied into a mixing hopper of the molding machine for reuse, the recycled chips are supplied to the lower center end of a funnel-shaped mixing hopper. While automatically supplying chips to the molding machine from the mixing hopper, the amount of recycled chips and new thermoplastic synthetic resin chips in the mixing hopper is automatically controlled to a nearly constant amount at all times. ,
Mixing and supplying both chips at a good approximately predetermined ratio by simply adjusting the distance between the new chip supply opening and the bottom side wall of the mixing hopper and supplying the new chips from the hopper by weight. ,
Further, the method according to claim 2 involves feeding a thermoplastic synthetic resin material into a mold of a thermoplastic synthetic resin molding machine to mold a product, and shredding runners, spools, etc. separated from the product. In a method for supplying materials to a thermoplastic synthetic resin molding machine in which recycled chips are automatically supplied into a mixing hopper of the molding machine for reuse, New thermoplastic synthetic resin chips are added to the recycled chips flowing in by adjusting the distance between the new chip supply opening and the bottom side wall of the mixing hopper so that the mixing ratio of both chips is approximately a predetermined ratio. The recycled chips and new chips are supplied from the mixing hopper and temporarily accumulated in the mixing hopper, and when the accumulated chips are supplied to the molding machine and the amount thereof decreases, the amount of the accumulated chips is By supplying new chips by weight into the mixing hopper, the amount of recycled chips lacking in the amount of chips supplied to the molding machine is automatically replenished, without using any special equipment. Recycled chips and new thermoplastic synthetic resin chips are automatically and easily supplied to a molding machine.

Furthermore, the apparatus according to claim 3 is a device for supplying a new thermoplastic synthetic resin material to the slope of the funnel-shaped bottom side wall of a mixing hopper for supplying a thermoplastic synthetic resin material of a synthetic resin molding machine. The supply openings of the hopper are opened at intervals, and on the other hand, a device for removing runners, spools, etc. from the molded product and a shredding device are located adjacent to the device for taking out the molded product directly below the mold. A transport path for recycled chips, which are the fine pieces, provided and attached to the shredding device is opened at a position where the recycled chips can flow down toward the supply port at the lower center end of the funnel-shaped mixing hopper, The hopper, which has an opening for supplying the new thermoplastic synthetic resin material fixedly facing downward, is installed on a support plate that is vertically adjustable and is attached to a support that stands on the machine base,
The mixing hopper is removably installed in the mixing hopper, and the supply port at the lower center of the mixing hopper is connected to a thermoplastic synthetic resin molding machine. It is sufficient to use a means of transporting recycled chips;
without using special mixing or measuring equipment,
A material supply device is provided which can automatically supply recycled chips and new thermoplastic synthetic resin chips to a molding machine continuously.

The illustrated embodiment will be described below.

FIG. 1 shows a slide fastener chain 1 immediately after demolding formed by the method and apparatus of the present invention, in which rows of fastener elements 2 are connected in series by runners 3, The spool 4 remains on the runner 3.

The method and apparatus of the present invention involve cutting the runner 3 and spool 4 from the fastener element row 2, cutting them into pieces to make recycled chips, continuously feeding the chips into a mixing hopper of an injection molding machine, and mixing the chips. A method and apparatus for supplying recycled chips and new thermoplastic synthetic resin chips from a hopper to an injection molding machine.

FIG. 2 shows a thermoplastic synthetic resin injection molding machine equipped with the device according to claim 3 and in which the methods according to claims 1 and 2 are carried out.
This is a schematic front view of the column, and a funnel-shaped mixing hopper 6 for supplying a thermoplastic synthetic resin material is attached to the heating cylinder 5, and a new thermoplastic synthetic resin material, a new thermoplastic synthetic resin material, is installed in the mixing hopper 6. A hopper 7 for supplying chips and supply pipes 9 and 10 to a cyclone 8 for transporting recycled chips obtained by shredding the runner 3, spool 4, etc. are opened.

A molding die 13 consisting of a fixed die 11 and a movable die 12 fixed to the heating cylinder 5 described above.
The fastener tape 14 is drawn in,
On the opposite edges thereof, rows of fastener elements 2 shown in FIG. 1 are injection molded to form a slide fastener chain 1.

Immediately below the molding die 13, a pair of rolls 15 for taking out the molded slide fastener chain 1,
A cutting device 16 for the runner 3 and the spool 4 is disposed, and a shredding device 17 for the cut runner 3 and the spool 4 is disposed directly below the device 16.
The shredding device 17 is equipped with a transfer device 20 consisting of a blower 18 and a transfer path 19 for transferring the shredded recycled chips. The opening is opened in the transfer cyclone 8, and the regenerated chips are transferred to the transfer cyclone 8 by transfer air generated by the blower 18.

The transfer cyclone 8 has a structure in which the regenerated chips transferred by the transfer air are separated from the transfer air, and the regenerated chips are discharged downward. Reference numeral 21 in FIG. 2 indicates the slide fastener chain 1 from which the runner 3 and spool 4 have been removed.
It is a storage box.

It should be noted that the recycled chip transfer device 20 is not limited to the device shown in the drawings, and any other device such as a belt conveyor device can of course be used.

FIG. 3 is a longitudinal sectional view of the mixing hopper 6 shown in FIG. 2, the hopper 7 for supplying new chips, and the cyclone 8 for transporting recycled chips, and is a longitudinal sectional view of the mixing hopper 6 shown in FIG. This shows the main parts of the device.

That is, the mixing hopper 6 has a supply port 23 at the center lower end of a funnel-shaped bottom side wall 22 connected to the inside of the heating cylinder 5 of the injection molding machine via the shutter 24, and is not equipped with any stirring device. do not have.

The supply opening 26 of the supply pipe 9 of the hopper 7 for supplying new chips 25 is opened substantially parallel to the slope of the bottom wall 22 with a distance H between them.

Further, the supply opening 27 of the supply pipe 10 of the regenerated chip transfer cyclone 8 is arranged so that the regenerated chips 31 can flow down toward the supply port 23 at the central lower end of the funnel-shaped mixing hopper 6.
3 and is open.

In particular, the above-mentioned hopper 7 is installed on a support plate 28 and is detachable from the mixing hopper 6, and the support plate 28 is attached to a support 30 erected on the machine base 29 so as to be vertically adjustable. .

The method invention of claim 2 is implemented by the above-mentioned apparatus, and the details thereof will be described below.

The runner 3 and spool 4 of the slide fastener chain 1 removed from the molding die 13 are removed,
The shredded and recycled chips 31 are transported from the cyclone 8 continuously through the supply pipe 10 to the supply port 23 in the funnel-shaped mixing hopper 6.
will be supplied to. Naturally, it is not possible to secure the amount of chips necessary for product molding with the supply of recycled chips alone, so new thermoplastic synthetic resin chips 25
supply. In this supply, the new chips 25 introduced into the hopper 7 are passed through the supply pipe 9 and automatically flow down by their own weight from the distance H between the supply opening 26 and the slope of the bottom side wall 22 of the mixing hopper 6. This is done by When the regenerated chips 31 and new chips 25 accumulate in the mixing hopper 6 and the supply opening 26 of the hopper 7 is blocked by the accumulated chips, the flow of new chips is automatically stopped. When the chips 25 and 31 in the mixing hopper 6 are used for injection molding and the amount of accumulated chips decreases, new chips 2 are added corresponding to the shortage of recycled chips 31 relative to the total amount of chips used.
5 is supplied again. In other words, although the recycled chips 31 are continuously supplied, the amount of chips accumulated in the mixing hopper decreases each time the chips are used by the molding machine, so the density of chips near the supply opening 26 of the hopper 7 becomes sparse. In order to replenish the space, new chips 25 are automatically flowed down by their own weight to promptly supply the required amount of chips corresponding to the shortage without excess or deficiency. In reality, the ratio of runners and spools to discharged products is 40 to 60%.
%, the ratio of recycled chips and new chips to the total amount of chips used will be approximately the same.
Therefore, recycled chips and new chips are mixed at a substantially predetermined ratio and are supplied to the injection molding machine for each shot. As a result, it is possible to reliably prevent thermal decomposition and color unevenness caused by concentrated supply of recycled chips. Furthermore, even if there is a slight fluctuation in the supply amount of recycled chips, the amount of new chips supplied will automatically follow it according to this method. It is possible to always maintain the ability to supply both in excess and deficiency.

In the above-described operation, when the accumulated chips are discharged from the supply port 23 of the mixing hopper 6, a recess is formed on the surface of the accumulated chips above the supply port 23, and the regenerated chips 31 are placed in this recess. Supply pipe 1
The regenerated chips 31 flow out and are supplied from the supply opening 27 of 0, and the new chips 25 flow into the surrounding area, so that the regenerated chips 31 and the new chips 2 can be mixed without using any special stirring device.
5 is approximately a predetermined mixing ratio, and flows into the molding machine in a generally uniform mixed state.

In addition, a new chip 25 is added to the regenerated chip 31.
When changing the mixing ratio of chips 25, the attachment position of the support plate 28 attached to the support column 30 is adjusted up and down, and the connection between the bottom side wall 22 of the mixing hopper 6 and the supply opening 26 of the new chips 25 is adjusted. The mixing ratio can be arbitrarily adjusted by adjusting the interval H between the two. If the interval H is increased, a new chip 2
If the interval H is made small, the mixing ratio of the new chip 25 becomes small.

Although the injection molding machine in which molten metal is intermittently supplied to the mold has been described above, this method can also be applied to an extrusion molding machine in which molten metal is continuously supplied. This is the method of claim 1.
In this case, new chips are continuously flowed down from the mixing hopper, but the replenishment effect on regenerated chips is no different from that described above.

FIG. 4 is a sectional view similar to FIG. 3 of another embodiment of the invention of claim 3, showing a supply pipe 34 of a hopper 33 for supplying new thermoplastic synthetic resin chips 32. Supply opening 3 at the lower end of
5 is opened horizontally and is opposed to the bottom side wall 37 forming the slope of the mixing hopper 36 with a distance therebetween. It has the same structure as that of the embodiment shown in FIG. 3, and produces similar functions and effects.

According to the inventions of claims 1 and 2 described above, if recycled chips obtained by shredding runners, spools, etc. are continuously fed into the mixing hopper, new chips can be used for molding. Since the system automatically supplies just the right amount of recycled chips to the total amount of chips, it is possible to reuse all of the recycled chips without wasting them. New chips and recycled chips can be mixed and supplied to a molding machine while always maintaining a roughly set ratio without using a mixing device or the like.

Further, since a certain amount of recycled chips is generated and the shortage is supplemented by new chips, the mixing ratio of chips becomes almost constant, and as a result, molding can be performed without color unevenness or thermal decomposition.

Even if there is a slight fluctuation in the supply of recycled chips, this method automatically replenishes it with new chips, so there will be no shortage of chips in the mixing hopper.

The method described in claim 1 is useful when used in an extrusion molding machine that continuously supplies molten metal into a molding die, and the method described in claim 2 is useful when the molten metal is supplied intermittently into a mold. It is useful if used in injection molding machines used in

According to the invention set forth in claim 3, recycled chips may be supplied by any means capable of transporting recycled chips into the mixing hopper, such as air transport means or conveyor means, or new chips may be supplied. can be carried out with a simple hopper without special measuring means, and mixing does not require the use of special mixing equipment, stirring equipment, etc., so the equipment is simple and does not require much maintenance. Generally, automatic supply of set ratios,
It becomes possible to perform mixing.

In addition, the position of the hoppers can be easily adjusted and removed, making it easy to adjust the amount of new chips supplied depending on the amount of recycled chips, or cleaning when changing colors, and is relatively inexpensive. It has the advantage that it can be provided to

[Brief explanation of the drawing]

Fig. 1 is a plan view of a slide fastener chain immediately after demolding formed by the method and apparatus of the present invention, and Fig. 2 is an example of an injection molding machine to which the invention of claim 3 is applied. FIG. 3 is a longitudinal sectional view of only the mixing hopper portion shown in FIG. 2, and FIG. 4 is a longitudinal sectional view of only the mixing hopper portion of another embodiment. 1: Slide fastener chain, 3: Runner, 4: Spool, 6: Mixing hopper,
7: Hopper for supplying new chips, 8: Transfer cyclone, 16: Cutting device, 17: Shredding device,
19: Transfer path, 20: Transfer device, 22: Bottom side wall,
25: New chip, 26, 27: Supply opening, 31: Recycled chip, H: Spacing.

Claims (1)

[Scope of Claims] 1. A thermoplastic synthetic resin material is fed into a mold of a thermoplastic synthetic resin molding machine to mold a product, and recycled chips obtained by shredding runners, spools, etc. separated from the product are molded. In a method of supplying materials to a thermoplastic synthetic resin molding machine in which materials are automatically supplied into a mixing hopper of a machine for reuse, the recycled chips are automatically supplied toward a supply port at the lower center of a funnel-shaped mixing hopper. and the opening for supplying new chips and the mixing hopper so that the amount of recycled chips and new thermoplastic synthetic resin chips in the mixing hopper is always controlled at a substantially predetermined ratio. The material is continuously flowed from the supply port of the mixing hopper into the thermoplastic synthetic resin molding machine while adjusting the distance between the new chips and the bottom side wall of the mixing hopper and allowing the new chips to fall under their own weight from the hopper to the bottom side wall of the mixing hopper. Supply method. 2. A thermoplastic synthetic resin material is fed into a mold of a thermoplastic synthetic resin molding machine to mold a product, and recycled chips obtained by shredding runners, spools, etc. separated from the product are placed in a mixing hopper of the molding machine. In a method of supplying materials to a thermoplastic synthetic resin molding machine in which the recycled chips are automatically supplied to a mixing hopper for reuse, the recycled chips are automatically supplied to a supply port at the lower center of a funnel-shaped mixing hopper, and The distance between the new chip supply opening and the bottom side wall of the mixing hopper is such that the amount of recycled chips and new thermoplastic synthetic resin chips in the mixing hopper is always controlled at approximately a predetermined ratio. The new chips are fed from the hopper by falling under their own weight to the bottom side wall of the mixing hopper, and are temporarily accumulated in the vicinity of the supply port at the lower center of the mixing hopper. By letting it flow into the molding machine and feeding new chips into the mixing hopper by weight according to the amount of reduction in the accumulated amount,
A method for supplying material to a thermoplastic synthetic resin molding machine, characterized by automatically replenishing a shortage in the amount of chips supplied to the molding machine. 3. The supply opening of the hopper for supplying a new thermoplastic synthetic resin material is spaced apart from the slope of the funnel-shaped bottom side wall of the mixing hopper for supplying the thermoplastic synthetic resin material of the synthetic resin molding machine. On the other hand, a runner from the molded product is opened adjacent to the molded product ejection device directly below the mold.
A cutting device such as a spool and a shredding device are provided,
The transport path for recycled chips, which are small pieces, attached to the shredding device is opened at a position where the recycled chips can flow down toward the supply port at the lower center end of the funnel-shaped mixing hopper. The hopper, whose opening for supplying thermoplastic synthetic resin material is fixed downward, is installed on a support plate that is attached to a column installed on the machine base so that its vertical position can be adjusted freely. The supply port at the lower center end of the mixing hopper is a material supply device for a thermoplastic synthetic resin molding machine, which is detachably installed.