JPH06262625A - Bulk density adjusting method for ground foamed resin and device therefor - Google Patents

Abstract

PURPOSE:To easily adjust the bulk density of ground foamed resin product to desired value by a method wherein the predetermined amount of the ground foamed resin product is agitated under the predetermined heating condition and, during the agitation, the ground foamed resin product is partially heat-shrunk. CONSTITUTION:Ground foamed resin article is fed through an opening 35 in an agitating tank 40 so as to be gradually moved along the slope of a guide plate 3 in order to be fallen in the agitating tank 40. The interior of the agitating tank has heated atmosphere having the temperature of about 100-200 deg.C by the heat emitted from heaters 48. Under the above-mentioned state, by turning a rotary disc 41, the ground article is homogeneously agitated by the interaction of agitating bars 44 and 45 and fixed bars 46 and, as the same time, heated. By the agitation under the above-mentioned heated atmosphere, the surface of the ground article are partially heat-shrunk. Next, by transferring treated matter through guide funnels 51 and 52 to a metering hopper 53 through an opened shutter 37 so as to measure the bulk density of the treated matter with a load cell. The metered treated matter is transferred to a conveyor 56 and then transferred outside the device concerned through a blower 55.

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 adjusting the bulk density of foamed resin crushed products.

[0002]

2. Description of the Related Art Conventionally, as a method of reusing a resin foam material such as waste polystyrene foam, the resin foam material is appropriately crushed and then mixed with a newly foamed primary material, and the novel material is secondarily foamed under heating and humidification. As a result, they are integrally molded as a foam-molded product. Such remanufactured products are effectively used, for example, as relatively large foamed resin blocks that are buried in the soil when building embankments on soft ground or when constructing platforms, or as core materials for floats. Has been.

At the time of molding, the current state is that the waste foam resin material which has been subjected to primary crushing by a crusher and, if necessary, secondary crushing is put into a molding machine as it is together with a new material, and heated steam is injected to perform foam molding. Is.

[0004]

Generally, in the production of foamed molded articles, desired temperature is controlled by adjusting the temperature of heated steam and its supply amount to adjust the foaming conditions to change its bulk density (foaming ratio). Trying to gain weight. When foam molding is performed using only a new material, this method can easily obtain a desired bulk density and achieve the initial adjustment purpose. However, the bulk density of crushed waste resin foam is usually lower than that before crushing, and the rate of change also changes depending on the crushing conditions. It has been difficult to always control the final product to be molded to a desired average bulk density (weight per unit volume) by adjusting the mixing ratio. In addition, after crushing, all resin materials are not always crushed to the same particle size and usually become a mixture of aggregates with different bulk densities. Moreover, it was virtually impossible to make them all the same weight.

Further, when it is desired to obtain a molded product having a bulk density equal to or higher than the bulk density of the waste resin material mixed in, the mixing ratio of the waste resin material crushed product must be reduced. , I couldn't get enough cost benefit. Also, when crushing resin products with a crusher, in addition to block-shaped crushed products, avoid including those that break into bubbles to form a thin film or aggregates into a long fiber form. I can't. Since the specific gravity of this kind of product is smaller than that of the block-shaped pulverized product, when the pulverized product is mixed with a new material and put into a foam molding machine, it becomes in a floating state. When molding was carried out for a long period of time, this floating substance caused the steam supply port of the molding machine to be clogged.

An object of the present invention is to eliminate the above-mentioned inconvenience caused by a crushed product when a crushed product of a waste resin foam is mixed with a new material to produce a new foam molded product. More specifically, it is an object of the present invention to provide a method and apparatus for making a crushed resin product have a desired bulk specific gravity so that a final product having a desired weight can be easily molded.

[0007]

In order to solve the above-mentioned problems and to achieve the object, the present invention is to stir a predetermined amount of a foamed resin pulverized product for a required time under a predetermined heating condition, while Disclosed is a method for adjusting the bulk density of a foamed resin crushed product, which comprises adjusting the overall bulk density by partially heat-shrinking the crushed product. Here, a step of taking out a part of the foamed resin pulverized product that has been stirred for a predetermined time under a predetermined heating condition and measuring its bulk density, and adjusting the heating condition and / or the stirring time based on the measured value is further added. Producing is a preferred embodiment.

The present invention further provides, as an apparatus for carrying out the above adjusting method, means for quantitatively supplying foamed resin crushed products,
A stirring tank for receiving and stirring the foamed resin crushed product from the quantitative supply means, a stirring means for stirring the foamed resin crushed product in the stirring tank, and a heating for heating the foamed resin crushed product in the stirring tank There is also disclosed a bulk density adjusting device for a crushed foamed resin product, comprising: a means and a measuring means for measuring the crushed foamed resin product that has been stirred and heated.

The term "crushed product of foamed resin" as used in the present invention refers to all crushed products of foamed resin that can be usually reused, and is not limited, but the present invention is particularly effective in the case of crushed polystyrene foam. To function.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in more detail based on the description of the embodiments with reference to the accompanying drawings. FIG. 1 is a partial cross-sectional view showing an embodiment of a processing apparatus suitable for carrying out the processing method of the present invention.

This processing apparatus is roughly divided into a crushed product accommodating means 10, a crushed product stirring / heating means 30, and a weighing / unloading means 50. The crushed product storage means 10 is a hopper 11 for receiving and holding a crushed product of a foamed resin material.
And a fixed amount feeding means 20. The hopper 11 has a charging port 12 and a discharging port 13, and its lower position and upper position are level sensors 1 made of appropriate means such as optical means.
4 and 15. A crushed product of a resin foam material is fed into the input port 12 from a conventionally known crusher (not shown) through a blower. A fixed amount feeding means 20 for measuring the discharged pulverized product and sending it to the pulverized product stirring / heating means 30, which will be described later, is located downstream of the discharge port 13. The fixed amount feeding means 20 has a valve function and a metering function, and is arranged in the axial direction of the rotary shaft 21 as shown in FIG.
It has a gutter-shaped measuring mass 22 and a motor 25 for rotating the measuring mass 22. The motor 25 and the rotary shaft are connected to each other via an appropriate speed control mechanism 26.

A guide plate 31 having a convex cross-sectional shape is located on the delivery side of the weighing mass 22, and the guide plate 31 extends into the crushed product stirring / heating means 30. That is, the stirring / heating means 30 has a stirring tank 40 surrounded by both side walls 32 and 33 and a cylindrical casing 34 located between the side walls as shown in FIG.
An opening 35 is formed at the center of the stirring tank 40, and the guide plate 31 extends into the stirring tank 40 through the opening 35. Further, the cylindrical casing 34 has a discharge opening 36 below, and a shutter 37 is slidably arranged near the discharge opening 36. The shutter 37
Is opened and closed by an appropriate shutter opening / closing mechanism 38 attached to the side wall 32.

A disc 41 having a diameter somewhat smaller than the inner diameter of the cylindrical casing 34 is provided in the stirring tank 40 at a position close to the side wall 32, and the disc 41 is rotatable on the side wall 32 via an appropriate bearing. It is fixed to a support shaft 42 supported by. Further, the support shaft 42 is connected to the motor 43 via an appropriate speed adjusting means (not shown). Further, the disc 4
In Fig. 1, two stirring rods 44a, 44b and 45a, 45b near the outer peripheral edge thereof and two stirring rods closer to the center side thereof are fixed at symmetrical positions with respect to the spindle 42, respectively. As shown in FIG. 1, it extends to the vicinity of the opposing side wall 33. On the other hand, two fixed rods 46a and 46b having a space inside are fixed to the side wall 33 so as to be positioned in the middle of the rotation loci of the stirring rods 44 and 45.

A flat heater 47 is attached to the inner peripheral wall of the cylindrical casing 34 and the wall surfaces of the side walls 32 and 33 defined by the cylindrical casing 34.
A rod-shaped heater 48 (FIG. 1) is provided in the internal space of the fixing rod 46.
The flat heater 47 and the rod-shaped heater 48
Is connected to a power supply unit (not shown) through an appropriate circuit.

Below the discharge opening 36 formed in the cylindrical casing 34, a measuring / carrying-out means 50 is provided.
That is, the guide funnel 5 is provided below the discharge opening 36.
1, 52 are located below the funnel 52, and a weighing hopper 53 is provided below the funnel 52 via an appropriate load cell 54 to form a side wall 32,
It is supported by 33. A conveyor 56 connected to the blower 55 is located near the discharge port of the weighing hopper 53. The guide funnels 51 and 52 are provided for the purpose of preventing the processed products in the cylindrical casing 34 from collectively dropping into the weighing hopper 53.

Further, this apparatus has a control box 100 and a level sensor 1 provided in a hopper 11.
4, 15, the speed control mechanism 26 of the motor 25, the speed control means of the motor 43, the power supply circuit of the flat heater 47 and the rod-shaped heater 48, the load cell 54 of the weighing hopper 53, and the blower 5.
5 is electrically connected to the drive circuit of 5 and controls the operation of the apparatus.

Next, the operation of this device will be described.
As described above, the accumulated resin foam material, which is mainly waste material, is crushed to an appropriate size by a crusher (not shown),
It is supplied from the inlet 12 into the hopper 11 by a blower. The level of the crushed product supplied is the upper level sensor 15
If it is detected by, the operation of the blower is stopped and the supply is stopped. The crushed product in the hopper 11 is measured by a predetermined amount by the rotation of the measuring mass 22 driven by the motor 25,
It drops on the guide plate 31 from the delivery side of the weighing mass 22. The dropped pulverized product is sent into the stirring tank 40 through the opening 35 formed in the side wall 33, gradually moves along the slope of the guide plate 31, and drops into the stirring tank 40.

Inner peripheral wall and side wall 3 of the cylindrical casing 34
The heater 47 attached to Nos. 2 and 33 and the heater 48 inserted into the fixing rod 46 are energized at this time, and the internal space of the stirring tank 40 is 100 ° C. to 2 ° C. due to the heat from the heater.
The heating atmosphere is about 00 ° C. In this state, the rotating disc 41 is rotated by driving the motor 43. As a result, the crushed product of the resin foam material put in is stirred by the stirring rods 44, 45.
And the fixing rod 46 interacts with each other, so that they are substantially homogeneously stirred and simultaneously heated. Due to the stirring under this heating atmosphere, the ground product is partially subjected to heat shrinkage from its surface. At the same time, suspended matter such as thin film-like ones formed by crushing the bubbles generated during the above-described pulverization or long-fiber-like ones gathered in a cross-linking state is also heat-contracted and becomes lump-like.

After the stirring process in this heating atmosphere is performed for a predetermined time, the shutter 37 is opened to guide the processed product to the funnel 5.
It is transferred to the weighing hopper 53 via 1, 52. In the weighing hopper 53, the bulk density of the processed material is measured by the load cell 54, and the measured value is sent to the control box 100. The processed products after the weighing are transferred from the weighing hopper 53 to the conveyor 56, and transferred from the blower 55 to an appropriate processed product collecting location outside the apparatus. After that, when necessary, it is mixed with a new material to form a resin foam product.

If there is a deviation between the measured value and the initial value, control is performed to correct the deviation. There are various methods for correcting the deviation. For example, a correction signal may be sent from the control box 100 to the temperature control mechanism of the heaters 47 and 48 to raise or lower the temperature inside the cylindrical casing 34, or the temperature of the feed to the control mechanism of the shutter 37 may not be changed. Alternatively, the stirring time may be lengthened or shortened. Furthermore, it is also possible to make adjustment by controlling the rotation speed of the motor 43. Moreover, you may control by combining each said means.

Although not shown in the drawing, a flow path switching valve may be provided at the blow-out port of the blower 55 to form a return path for returning the processed material having a bulk density of a predetermined value or less to the hopper 11. As the treatment progresses, the level of the crushed product in the hopper 11 decreases. When the lower sensor 14 detects the level of the crushed product, the crusher is operated to supply the crushed product into the hopper 11.

Hereinafter, this operation is performed in the control box 1
It is repeatedly performed based on the command from 00. The resin foam material pulverized by this treatment is adjusted to a desired bulk density. It will be easily understood that the set bulk specific gravity value can be changed during the operation. The above description is only one description of one embodiment of the method and apparatus of the present invention, and there are many other variations.

For example, the type of level sensor provided in the hopper 11 is arbitrary, and the level sensor itself may be provided. As the fixed amount feeding means provided on the outlet side of the hopper 11, any means can be used as long as it can repeatedly supply a predetermined amount. For example, the supply means may be a shutter plate that opens and closes at regular time intervals.
The guide plate 31 having an upwardly convex cross-sectional shape is provided for the purpose of preventing the crushed product from suddenly forming a lump into the cylindrical casing, and a fixed amount feeding means provided on the outlet side of the hopper 11 is provided. For example, in the case of a form in which a small number of units are supplied multiple times, a flat guide plate may be used.

The number of stirring rods and fixed rods and their mounting positions are also arbitrary, and may be appropriately determined experimentally so as to obtain more uniform stirring of the crushed product. The shape does not have to be a cylindrical rod-shaped body as shown in the figure, and may be rectangular or oval. Furthermore, flat and rod-shaped heaters for creating a heating atmosphere in the cylindrical casing are also shown as examples of the heating means, and it is also possible to feed dry or humidified high temperature air to the crushed product, which is generated during stirring. The frictional heat between the same or the stirring rod and the crushed product may be used. Also,
It is also possible to use them in appropriate combination. In particular,
The flat heater 47 can be attached to the cylindrical casing 34 and the outer side wall portions of the side walls 32 and 33, or can be attached to both inner and outer sides. Any means for measuring the bulk density with a weighing hopper can be used, and a conventionally known bulk density measuring method can be appropriately used. In the case of a crushed product of such a resin foam material, a bulk density measuring method by measuring the amount of light transmission can be effectively used.

[Example of use] Styrofoam waste material was pulverized with a pulverizer to an average particle size of 3 mm, and its bulk density was measured to be about 0.01 g / cc. The crushed product is put into the apparatus shown in the drawing and the temperature in the cylindrical casing is adjusted to 15
The mixture was stirred at 0 ° C for 5 minutes. When the bulk density of the agitated product was measured with a weighing hopper, it was about 0.02 g / cc.
I was able to When the bulk density was measured by continuing stirring for further 5 minutes, it could be about 0.12 g / cc.

[0026]

According to the present invention, it is possible to easily adjust the bulk specific gravity of a resin foam pulverized product pulverized by a pulverizer to a desired value. Further, when treating a mixture of pulverized products having different specific gravities, it is possible to finally adjust the mixture to have a uniform bulk density. As a result, it becomes possible to reliably perform weight control when molding a product in which the recycled foam material treated according to the present invention and the novel foam material are mixed. Further, since it is possible to granulate a metered amount of suspended matter contained in the crushed product, the steam supply port of the molding machine will not be clogged even if molding is performed for a long period of time.

[Brief description of drawings]

1 is a cross-sectional view of a processing apparatus according to the present invention.

FIG. 2 is a diagram showing an example of a fixed amount feeding means.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a partially cutaway perspective view for explaining a stirring tank.

[Explanation of symbols]

11 ... Hopper, 20 ... Fixed amount supply means of crushed foamed resin product, 40 ... Stirring tank, 44, 45 ... Stirring rod, 46 ... Fixed rod, 47, 48 ... Heater, 53 ... Measuring hopper, 54 ...
Load cell

Claims (3)

[Claims] 1. The entire bulk density is adjusted by stirring a predetermined amount of the foamed resin pulverized product under a predetermined heating condition for a required time, and partially shrinking the foamed resin pulverized product during the stirring. A method for adjusting the bulk density of a foamed resin pulverized product. 2. A step of taking out a part of a foamed resin pulverized product which has been stirred for a predetermined time under a predetermined heating condition, measuring the bulk density thereof, and adjusting the heating condition and / or the stirring time based on the measured value. The method for adjusting the bulk density of a crushed foamed resin product according to claim 1, further comprising: 3. A fixed amount supply means for the foamed resin crushed product, a stirring tank for receiving and stirring the foamed resin crushed product from the fixed amount supply means, a stirring means for stirring the foamed resin crushed product in the stirring tank, A bulk density of the crushed foamed resin product, comprising: a heating means for heating the crushed foamed resin product in the stirring tank, and a measuring means for measuring the crushed foamed resin product which has been stirred and heated. Adjustment device.