JPH0585230B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to an apparatus for reducing the volume of waste synthetic resin so that it can be effectively reused.

[Conventional technology and issues]

Currently, a huge amount of used synthetic resin is generated. Moreover, its amount is increasing significantly. Most used synthetic resin is disposed of by incineration. Incinerators for waste synthetic resin have a short lifespan;
This is causing incineration costs to rise. Also, depending on the type of synthetic resin, toxic gas is generated when incinerated. Some of the used synthetic resin is used to mold recycled products. To reuse waste synthetic resin, the dirty synthetic resin is washed, melted, formed into pellets, and reused. This method has the disadvantage that processing costs for processing waste synthetic resin into pellets are high. In order to effectively reuse the huge amount of waste synthetic resin generated, it is important to find a way to reduce processing costs and volume. The reduced volume of waste synthetic resin is
Can be remolded using a molding machine. A device has been developed that reduces the volume of waste synthetic resin by forcing it into a cylinder with a tapered tip (Japanese Patent Application Laid-open No. 82879/1982). This volume reduction device heats the tip of the cylinder in order to melt the extruded waste synthetic resin with heat. This volume reduction device is
The waste synthetic resin is pushed into the cylinder using a piston, heated and melted at the tip, and then extruded from the cylinder in a reduced volume state. This type of volume reduction device requires a large amount of thermal energy to heat the cylinder to a high temperature.
This increases running costs. As a volume reduction device that solves this drawback, a device that melts synthetic resin by self-heating has been developed (Japanese Utility Model Publication No. 62-22340). This device has a screw shaft built into the cylinder that extrudes waste synthetic resin. Narrow the opening at the tip of the cylinder,
In this part, the synthetic resin generates heat through frictional heat.
The tip of the screw shaft is shaped to reduce the amount of synthetic resin transferred so that the amount of heat generated by the synthetic resin increases at the tip of the cylinder. A volume reduction device with this structure can reduce the thermal energy used to heat the cylinder. However, it is difficult to efficiently reduce the volume of all waste thermoplastic synthetic resins. The reason for this is that the amount of heat generated varies significantly depending on the type of synthetic resin and the moisture content. In order to solve this drawback, the present inventor developed a volume reduction device shown in FIG.
-199917=Refer to Japanese Unexamined Patent Publication No. 3-65284). This volume reduction device includes a cylinder 1, a drive shaft 2 rotatably disposed within the cylinder, a tapered shaft 6 to be rotated by the drive shaft 2, and a motor 4 to rotate the drive shaft 2. The cylinder 1 is provided with a tapered heat generation volume reduction opening 7 whose cross-sectional area increases toward the open end so that the heat generation state can be adjusted depending on the type of waste synthetic resin. The surface of the tapered shaft 6 is provided with protrusions. The tapered shaft 6 has a tapered shape that gradually becomes thicker in the extrusion direction of the waste synthetic resin so that a predetermined gap is formed between the tapered shaft 6 and the heat generation volume reduction opening 7. This volume reduction device reduces the volume of waste synthetic resin under the following conditions. Waste synthetic resin is fed into cylinder 1. The synthetic resin fed into the cylinder 1 is forced forward by the screw shaft 5. The waste synthetic resin pumped within the cylinder 1 is rubbed between the heat-generating volume reduction opening 7 and the tapered shaft 6 and generates heat by itself. The waste synthetic resin self-heats in this part because
The rotating tapered shaft 6 opens the heat generating volume reducing opening 7.
This is because the waste synthetic resin is force-fed while being pressed against the inner surface of the container and being subjected to friction. The calorific value of the waste synthetic resin is adjusted by the distance between the inner surface of the heat generation volume reduction opening 7 and the tapered shaft 6. If this gap is narrowed, the waste synthetic resin will be strongly pressed and the amount of heat generated will increase. On the other hand, if this gap is adjusted to be wide, the frictional force pressing the waste synthetic resin will be reduced, and the amount of heat generated will be reduced. However, if the gap between the tapered shaft 6 and the heat generation volume reduction opening 7 is narrowed in order to increase the amount of heat generated, the volume of the synthetic resin to be reduced and extruded will be reduced, resulting in a reduction in processing capacity. For this reason, it is important for equipment to reduce the volume of waste synthetic resin to improve the efficiency of self-heating of the synthetic resin and to increase its processing capacity. however,
A volume reduction device in which a protrusion is provided on the surface of the tapered shaft 6 cannot achieve a sufficiently satisfactory volume reduction processing ability, and there is a strong desire for a device that can efficiently reduce volume. This invention was developed with the aim of solving this drawback, and the important objectives of this invention are to increase the self-heating efficiency of waste synthetic resin, increase the volume reduction processing capacity, and furthermore, To provide a volume reduction device capable of reducing the volume of waste synthetic resin by heating it to a uniform state.

[Means to solve conventional problems]

The waste synthetic resin volume reduction device of the present invention has the following configuration in order to achieve the above-mentioned object. (a) The volume reduction device consists of cylinder 1 and cylinder 1.
The drive shaft 2 includes a drive shaft 2 rotatably disposed therein, and a motor 4 that rotates the drive shaft 2. (b) The cylinder 1 is provided with a tapered heat generation volume reduction opening 7 whose cross-sectional area increases toward the open end. (c) A tapered shaft 6 is connected to the drive shaft 2. (d) The tapered shaft 6 has a tapered shape that gradually becomes thicker in the direction of extrusion of the waste synthetic resin so that a predetermined gap is created between the tapered shaft 6 and the heat generation volume reduction opening 7. (e) A plurality of protrusions 13 are provided on the outer periphery of the tapered shaft 6 to extend in the axial direction. (f) The protrusion 13 is located on the front side 1 in the cross-sectional shape.
3A and the rear surface 13B have different slopes. (g) The front side surface 13A of the protrusion 13 is an inclined surface with a gentle upward slope, and the rear side surface 13B is a descending surface with a steeper downward slope than the front side surface 13A.

[effect]

In the volume reduction device of the present invention, the waste synthetic resin supplied to the cylinder is rubbed in the gap between the heat-generating volume reduction opening 7 and the tapered shaft 6, heated and melted, and then extruded from the cylinder. FIG. 1 shows a state in which the waste synthetic resin is self-heated between the heat generation volume reduction opening 7 and the tapered shaft 6. As shown in this figure, the waste synthetic resin moves between the protrusion 13 and the heat-generating volume-reducing opening 7 as shown by the arrow, and is heated, melted, and reduced in volume. That is, the waste synthetic resin is crushed by the protrusions 13 provided on the surface of the tapered shaft 6, and is rubbed and reduced in volume. The front side surface 13A of the protrusion 13 has a gentle upward slope, and the rear side surface 13B has a steep downward slope. When the convex strip 13 having this shape moves, the waste synthetic resin is subjected to friction, heating, and volume reduction in the following conditions. a The waste synthetic resin in front of the protrusion 13 is sent toward the upper end of the protrusion 13 along the upwardly sloped protrusion front side surface 13A. b The waste synthetic resin moving in the direction of the arrow along the front side surface 13A of the protrusion 13 is gradually pressed with stronger pressure. c The waste synthetic resin press-fitted into the narrow gap between the protruding strip 13 and the heat generating volume reducing opening 7 is pressed with the strongest pressure, and is strongly pressed against the inner surface of the heat generating volume reducing opening 7 by the protruding strip 13 and is efficiently rubbed. . d The synthetic resin that has passed through the upper end surface of the protrusion 13 passes through the protrusion 13 smoothly due to the steep descending surface. In this state, the waste synthetic resin is
3A and the upper end surface, self-heating is generated extremely efficiently. The waste synthetic resin is rubbed by gradually pressing the front side surface 13A of the protrusion 13 strongly, and then the waste synthetic resin is rubbed by pressing strongly in the narrow gap between the upper end of the protrusion 13 and the heat generation volume reduction opening 7, and then The reason is that the waste synthetic resin that has passed through 13 is smoothly transferred to the back surface of the protruding strip 13. Therefore, the waste synthetic resin volume reduction device of the present invention can self-heat the supplied waste synthetic resin extremely efficiently, increasing the processing capacity per unit time, and reducing a large amount of waste synthetic resin in a short time. Achieve features that can be tolerated. Furthermore, the volume reduction device of this invention
Since the processing capacity is improved by increasing the self-heating efficiency of the waste synthetic resin, there is no need to supply a large amount of thermal energy to reduce the volume of a large amount of waste synthetic resin. Therefore, overall, it has the feature of saving energy and reducing the volume of a large amount of waste synthetic resin.

[Preferred embodiment]

Embodiments of the present invention will be described below based on the drawings. However, the embodiments shown below are illustrative of a volume reduction device for embodying the technical idea of the present invention, and the volume reduction device of the present invention is characterized by
The shape, structure, and arrangement are not limited to the following structures. Various modifications may be made to the volume reduction device of the present invention within the scope of the claims. Furthermore, in order to make the claims easier to understand, the numbers corresponding to the members shown in the embodiments are indicated in the "Claims column" and "Means for Solving the Conventional Problems". The members shown in the "Column" and "Column of Functions and Effects" are appended with notes. However, the members shown in the claims are by no means limited to the members of the embodiments. The waste synthetic resin volume reduction device shown in the schematic cross-sectional view in FIG. 2 and the perspective view in FIG. Tapered shaft 6 connected to the tip
and a motor 4 that rotates the drive shaft 2. The cylinder 1 consists of a volume reduction cylinder section 1A that heats and reduces the volume of waste synthetic resin, and a pushing cylinder section 1B that presses the waste synthetic resin into the volume reduction cylinder section 1A. The pushing cylinder part 1B is connected to the tip of the volume reducing cylinder part 1A, and the pushing cylinder part 1B and the volume reducing cylinder part 1A are connected in series. The volume reduction cylinder section 1A reduces the volume of waste synthetic resin and discharges it from the cylinder 1. The volume reduction cylinder part 1A is provided with a tapered heat generation volume reduction opening 7 whose cross-sectional area increases toward the opening end so that the heat generation state can be adjusted depending on the type and moisture content of the waste synthetic resin. . An enlarged sectional view of the heat generation volume reduction opening 7 and the tapered shaft 6 is shown in FIG. As shown in this figure, the heat generation volume reduction opening 7 is provided with a plurality of grooves 14 extending in the axial direction. The groove 14 is a heat generating volume reducing opening 7.
To reduce slippage between the surface of the plastic and the waste synthetic resin. Reducing slips allows waste synthetic resin to self-heat more efficiently. 5 to 50 grooves 14 are provided on the inner surface of the heat generation volume reduction opening 7. The depth and width of the groove 14 are designed to be in the range of 1 to 10 mm. The cross-sectional shape of the groove 14 can be semicircular as shown in FIG. 1, or rectangular or trapezoidal (not shown). By the way, although this volume reduction device ideally reduces the volume by completely melting the waste synthetic resin, it is not necessarily necessary to completely melt the waste synthetic resin by heating it to a temperature higher than the melting temperature. This is because the volume of the waste synthetic resin can be sufficiently reduced even when it is in a semi-molten state or a partially melted state. The heat generating volume reduction opening 7 of the volume reduction cylinder portion 1A includes:
A tapered shaft 6 is provided. Tapered shaft 6
is connected to the tip of the drive shaft 2. A protrusion 13 is provided on the surface of the tapered shaft 6 and extends in the axial direction. The cross-sectional shape of the protrusion 13 is shown in FIG. As shown in this figure,
The protrusions 13 have different slopes on the front side 13A and the rear side 13B, with the front side 13A being a gentle upward slope, and the rear side 13B being a steeper downward slope than the front side 13A. There is. The front side surface 13A has a curved surface whose slope gradually becomes steeper. Preferably, the front side surface 1 of the protrusion 13
3A has a curved surface having a predetermined radius of curvature. Length L of the inclined portion of the front side surface 13A of the protrusion 13
is adjusted to an optimum value in consideration of the height H of the protrusion 13. The ratio between the length L of the inclined portion and the height H of the protrusion 13 is usually adjusted to a range of 0.3≦L/H≦5, preferably 0.5≦L/H≦3. Further, the height H of the protrusion 13 gradually decreases toward the tip of the tapered shaft 6, but is designed to be 3 to 40 mm at the highest portion. As shown in FIG. 4, the protrusions provided on the surface of the tapered shaft can be arranged by extending short protrusions 13 in the axial direction so as to be spaced apart from each other. The tapered shaft 6 is connected to the tip of the drive shaft 2 so as to be movable in the axial direction. Therefore, a square hole into which the drive shaft 2 is pushed is provided at the center of the tapered shaft 6. The tip of the drive shaft 2 has a prismatic shape that can be slidably inserted into a square hole. The square column of the drive shaft 2 is inserted into the square hole of the tapered shaft 6, and the tapered shaft 6 is rotated by the drive shaft 2.
When the tapered shaft 6 moves in the axial direction, the depth at which the square column is inserted into the square hole changes. The tapered shaft 6 is linearly connected to the drive shaft 2. The tapered shaft 6 is supported by the tailstock 3 so as to be movable in the axial direction of the drive shaft 2.
The tapered shaft 6 moves in the axial direction together with the tailstock 3. Therefore, the tapered shaft 6 is supported by the tailstock 3 in a state where it can rotate freely but does not move in the axial direction. A shaft protruding from the tip of the tapered shaft 6 is supported by the tailstock 3 via a bearing. The tailstock 3 is movable in the axial direction of the volume reduction cylinder portion 1A and fixed at the moving position.
attached to the base. The tailstock 3 moves the taper shaft 6 in the axial direction to adjust the gap between the taper shaft 6 and the volume reduction cylinder portion 1A. When the tailstock 3 is brought closer to the cylinder 1 and the tapered shaft 6 is pushed deeply into the volume reducing cylinder section 1A, the gap between the tapered shaft 6 and the volume reducing cylinder section 1A becomes narrower. On the other hand, when the tailstock 3 is separated from the cylinder 1, the gap between the tapered shaft 6 and the volume reducing cylinder portion 1A becomes wider. When the gap between the tapered shaft 6 and the volume reduction cylinder part 1A becomes narrower, the waste synthetic resin is rubbed together in the narrow gap while being strongly pressed. As a result, waste synthetic resins with high calorific value and high melting temperature,
Alternatively, waste synthetic resin with a high moisture content can be completely melted at a higher temperature. When the gap between the tapered shaft 6 and the volume reduction cylinder part 1A is adjusted to be wide, the pressing force on the waste synthetic resin becomes weaker, and the amount of heat generated decreases. Therefore, this state is optimal for processing waste synthetic resins that have a low melting temperature or a low moisture content. In this state,
The amount of synthetic resin discharged per unit time increases. Therefore, the tapered shaft 6 and the volume reducing cylinder portion 1A
The gap between the two is adjusted to the optimum calorific value and processing amount, taking into consideration the type and moisture content of the synthetic resin to be supplied. By the way, since the waste synthetic resin volume reduction device of the present invention reduces the volume by causing the synthetic resin to self-heat, the volume reduction cylinder part 1A does not necessarily require a heating means such as a heater, but it is possible to install a heater in this part. Needless to say, it is also possible to equip it. Even if a heater is installed, the waste synthetic resin generates heat by itself in the volume reduction cylinder section 1A, so the heating capacity of the heater can be reduced. Push cylinder part 1B into volume reduction cylinder part 1A
are connected. The push-in cylinder portion 1B opens upward and has a waste synthetic resin supply port 8 opened therein. Inside the pushing cylinder portion 1B, a screw shaft 5 and a rotary cutter 10 are arranged side by side in the same horizontal plane. Therefore, the push-in cylinder portion 1B is formed into a cylindrical shape that can accommodate two shafts. The screw shaft 5 is rotatably disposed inside the push cylinder portion 1B. Screw axis 5
is rotated by a motor 4 and pumps the waste synthetic resin fed into the push cylinder part 1B from the supply port 8. Therefore, on the surface of the screw shaft 5,
A spiral fin 9 is provided. The rotary cutter 10 arranged parallel to the screw shaft 5 cuts the waste synthetic resin supplied from the supply port 8 into small pieces with the screw shaft 5, and pressure-feeds it to the volume reduction cylinder section 1A. Therefore, the surface of the rotary cutter 10 is provided with a plurality of vertically extending protrusions 11, and the overall shape is processed into a spline shape. The tip edge of the protrusion 11, in other words, the top edge of the peak of the protrusion 11 contacts or comes very close to the tip edge of the fin 9 of the screw shaft 5, and the fin 9 of the screw shaft 5 and the protrusion of the rotary cutter 11 and cut the waste synthetic resin. Although not shown in the drawings, the rotary cutter 10 may have a plurality of short protrusions extended in the axial direction and arranged in a staggered manner instead of a spline shape. The rotary cutter 10 is rotated in the opposite direction to the screw shaft 5 so as to cut the waste synthetic resin by sandwiching the rotary cutter 10 with the screw shaft 5. In the volume reduction device shown in FIG. 2, a rotary cutter 10 and a screw shaft 5 are rotated in opposite directions via a gear 12. The inner shape of the pushing cylinder portion 1B is processed so that the fin tip of the screw shaft 5 and the tip edge of the convex strip of the rotary cutter 10 are close to each other, for example, 0.1 to 5 mm. In this way, the push cylinder part 1B which houses the rotary cutter 10 parallel to the screw shaft 5
Since the supplied waste synthetic resin is cut into small pieces and sent under pressure to the volume reduction cylinder section 1A, it is cut into long string-like,
It has the advantage that it can supply waste synthetic resin in the form of sheets, bags, etc. as is, and that it can make waste synthetic resin of various shapes into shapes that can be efficiently rubbed in the next process. However, depending on the type and shape of the waste synthetic resin,
The rotary cutter is not necessarily required, and the waste synthetic resin can be force-fed to the volume reduction cylinder part using a cylindrical pushing cylinder part in which the screw shaft and the screw shaft are built in with little clearance. The rear end of the screw shaft 5 is connected to a deceleration motor 4 and driven to rotate. Incidentally, at the rear end of the push-in cylinder section, a water drain port (not shown) is preferably opened at the bottom thereof. By opening a water outlet here, when waste synthetic resin with a high moisture content is supplied, the moisture contained in the synthetic resin is removed, and the synthetic resin with a low moisture content can be supplied to the volume reduction cylinder section.

[Brief explanation of drawings]

FIG. 1 is an enlarged sectional view showing the gap between the heat generating volume reduction opening and the tapered shaft of a volume reduction device according to an embodiment of the present invention, and FIGS. 2 and 3 are discards according to an embodiment of the present invention. A schematic sectional view and a perspective view of a synthetic resin volume reduction device, and FIG. 4 is a side view showing another embodiment of the tapered shaft. 1... Cylinder, 1A... Volume reduction cylinder part, 1B... Pushing cylinder part, 2... Drive shaft,
3...Tailstock, 4...Motor, 5...Screw shaft, 6...Tapered shaft, 7...Heating volume reduction opening,
8... Supply port, 9... Fin, 10... Rotary cutter, 11... Protrusion, 12... Gear, 13...
...Convex stripe, 13A...front side, 13B...rear side,
14...Groove.

Claims (1)

[Claims] 1. A waste synthetic resin volume reduction device having the following configuration. (a) The volume reduction device consists of cylinder 1 and cylinder 1.
The drive shaft 2 includes a drive shaft 2 rotatably disposed therein, and a motor 4 that rotates the drive shaft 2. (b) The cylinder 1 is provided with a tapered heat generation volume reduction opening 7 whose cross-sectional area increases toward the open end. (c) A tapered shaft 6 is connected to the drive shaft 2. (d) The tapered shaft 6 has a tapered shape that gradually becomes thicker in the direction of extrusion of the waste synthetic resin so that a predetermined gap is created between the tapered shaft 6 and the heat generation volume reduction opening 7. (e) A plurality of protrusions 13 are provided on the outer periphery of the tapered shaft 6 to extend in the axial direction. (f) The protrusion 13 is located on the front side 1 in the cross-sectional shape.
3A and the rear surface 13B have different slopes. (g) The front side surface 13A of the protrusion 13 is an inclined surface with a gentle upward slope, and the rear side surface 13B is a descending surface with a steeper downward slope than the front side surface 13A.