JP3056436B2 - Raw material cutting method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for cutting raw materials, and further compresses (reduces the volume of) waste such as plastic and discharges it as a high-density material, or compresses waste such as plastic Suitable for a twin screw extruder that heats (self-heating or external heating), softens and melts the thermoplastic material, mixes it with non-molten material (wood chips, paper chips, etc.), solidifies, reduces the volume, and discharges. The present invention relates to a cutting device that can be implemented in a single machine.

[0002]

2. Description of the Related Art A twin screw extruder as described above is disclosed in Japanese Patent Publication No. 7-29356 proposed by the present applicant. In this extruder, the rotary blade is continuously rotated at a predetermined rotation speed by a drive motor constituting a fixed-size cutting mechanism, and the raw material (melt) discharged in a rod shape from the discharge hole is rotated once by the rotary blade. Is cut off once. When cutting to a predetermined length (for example, 15 mm x 150 mm), the rotary blade must rotate slowly at a peripheral speed of about 0.3 m / sec. However, when rotated slowly, the melt is soft, so the cut surface becomes skewed or torn, resulting in a problem that not only the added value of the product is inferior, but also the filling rate decreases when bagging is performed. is there. On the other hand, when the rotation speed is increased, the cut dimension is shortened accordingly, and the subsequent handling becomes troublesome, and the filling rate is increased. That is, there is a problem that the apparent specific gravity (bulk specific gravity) increases.

[0003]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems and can improve the precision of a cut surface without making the cut surface oblique. It is an object of the present invention to provide a raw material cutting method and an apparatus thereof capable of suppressing an increase in the amount of raw material.

[0004]

According to a first aspect of the present invention, there is provided a method for cutting a raw material, wherein a rod-shaped raw material fed by a rotary screw of an extruder and discharged from a discharge hole is rotated at a high speed. When cutting to a predetermined length with a rotary blade, the rotary blade after cutting the raw material by rotation is temporarily stopped and intermittently rotated so as to rotate again after a predetermined time.

According to a second aspect of the present invention, there is provided a raw material cutting device provided near a discharge hole of an extruder, for cutting a rod-shaped raw material discharged from the discharge hole into a predetermined length, and a rotary blade. A driving member for rotating the blade at high speed, and a control member for intermittently controlling the rotation of the driving member so that the rotating blade temporarily stops rotating after cutting the raw material by rotation and re-rotates after a predetermined time. It is characterized by having.

According to a third aspect of the present invention, there is provided a raw material cutting device, wherein a raw material supply port is provided at an upper portion at one end and an end plate having a plurality of discharge holes is mounted at the other end.
A pair of rotating shafts rotatably provided in a direction facing the inside of the body, a feed screw provided on the rotating shaft, and a rod-shaped raw material provided near the discharge hole and discharged from the discharge hole. In a raw material cutting device of a twin-screw extruder equipped with a rotary blade for cutting at a predetermined length and a driving member for rotating this rotary blade at high speed, after the rotary blade cuts the raw material by rotation of the driving member, A control member for intermittently controlling the rotation so as to temporarily stop the rotation and restart the rotation after a predetermined time is provided.

[0007]

An embodiment of the present invention will be described with reference to the drawings. This embodiment is applied to a twin screw extruder. 1 is a partially cutaway front view of the twin-screw extruder, FIG. 2 is a partially cutaway and partially cutaway plan view of the same, and FIGS. 3 and 4 are partially cutaway side views of the same. is there. 3 and 4, a portion A is a partially broken portion along the line AA in FIG. 1, a portion B is a partially broken portion along the line BB in FIG.
Parts C 'and C "are partially broken sections along the lines C'-C' and C" -C ", respectively. In these drawings, reference numeral 1 denotes a twin-screw extruder, which is installed on the base plate 2. Body 3
It has. The body 3 has an elongated shape having two substantially circular side cross-sections, and is divided into two in the length direction and the vertical direction, and is assembled by being connected with bolts and nuts. A supply port 4 for an object to be processed (raw material) such as a plastic waste is provided in an upper portion of one end of the body 3 which is closed. The other end of the body 3 is opened to form a discharge port, and the discharge port is closed by an end plate 5. The end plate 5 has a bracket 7 protruding from one side thereof connected to a bracket 8 provided on the body 3 by a connecting pin 9 (FIG. 3, FIG. 3).
4) The pin rotates as a fulcrum to open and close the discharge port, and the end plate 5 is fastened to the body 3 by the hydraulic clamp mechanism 11 in a closed state (FIG. 1).

The end plate 5 is provided with a plurality of discharge holes 13 on the same circumference centered on each circle of the body 3, and a similar discharge hole 14 is provided at the center thereof. A split type fuselage liner (lining material) 15 which is divided into a plurality of pieces in the longitudinal direction and the vertical direction on the inner surface of the fuselage 3 and has wear resistance is provided.
Mounted by 16. A pair of rotating shafts 17 and 18 are provided in the body liner 15 so as to be rotatable in parallel with each other and in opposite directions. The rotary shaft 17 is the body liner 15 inner part of the cross section is hexagonal, each six segmented feed screw 20 ₁ to 20 ₆ in its outer surface is fitted fixed to engage with each other. And each feed screw
20 _{1 to} 20 ₆ are assembled so as to form a continuous spiral. The rotary shaft 17, 18 has been a hexagonal cross section in this example, may be connected to the screw 20 ₁ to 20 ₆ sends thereto as a circular key or the like. Although dividing the feed screw 20 ₁ to 20 ₆ to six, the rotary shaft 1 integrally Although one feed screw
You may make it fit and fix to 7 and 18.

FIG. 5 shows a scraping member 23 fixed to the end plates 5 by bolts 22 at the ends of the rotating shafts 17 and 18 on the end plate 5 side. The scraping member 23 has a plurality of scraping blades 24 on its outer periphery for cutting a relatively long workpiece or a plate-shaped raw material which is to close the discharge nozzle 33 to be described later.
The rotation of 18 rotates as shown. In addition, rotating shaft 1
Since the scraping members 23 fixed to 7 and 18 have the same structure except that they are arranged symmetrically, the following describes the scraping members 23 fixed to the rotating shaft 17 as one of them. FIG.
This will be described with reference to FIG. FIG. 7 shows FIG.
9 is a cross-sectional view taken along the line DD of FIG. 8, and FIG. 9 is a partially enlarged view taken along the line EE of FIG. A groove 25 is formed on the downstream side surface (the surface facing the end plate 5) of the scraping member 23. The direction of the concave groove 25 is inclined by a predetermined angle θ ₁ (6 ° in the illustrated case) with respect to the radial axis a passing through the center of the scraping member 23 toward the rotation direction side of the scraping member 23, whereby The workpiece cut by the scraping blade 24 is guided and transferred to the discharge nozzle 33 as the scraping member 23 rotates.

FIG. 10 shows a wear-resistant crushing plate 28 fitted and arranged in a recess 27 formed on the upstream side surface of the end plate 5 (the surface facing the scraping member 22). Discharge holes 30 and 31 communicating with the discharge holes 13 and 14 of the end plate 5 are provided through the grinding plate, and between these discharge holes 30 and 31 and the discharge holes 13 and 14 of the end plate, FIG. The discharge nozzle 33 is detachably attached as shown in FIGS. Further, grooves 35 and 36 are formed on the upstream side surface of the grinding plate 28. As shown in FIGS. 11 and 12, the direction of the concave groove 35 is set with respect to the radial axis b passing through the center of the grinding plate 28 and the scraping member 23.
Is inclined at a predetermined angle θ ₂ on the opposite side of the rotation direction (6 in the illustrated case).
0 °), and the direction of the groove 36 is substantially parallel to the radial axis b, so that the workpiece is discharged in cooperation with the groove 25 of the scraping member 23 as the scraping member 23 rotates. It is guided and transferred to the nozzle 33 side.

FIGS. 13A and 13B show details of the hydraulic clamping mechanism 11 of the end plate 5, wherein FIG. 13A shows a tightened state and FIG. 13B shows a state before the tightening. Reference numeral 40 denotes a fastening member disposed on the upper and lower portions of the flange portion 3a of the body 3 and the end plate 5, and is formed on the inclined side surfaces 41 and 42 formed in the recess 43 of the fastening member 40 and the flange portion 3a of the body 3. The inclined surface 3b and the inclined surface 5a formed on the end plate 5 are fitted or separated in a wedge shape. A hydraulic cylinder 45 is disposed on the side of the fastening member 40 opposite to the recess 43. The rod of this hydraulic cylinder 45
46 is loosely fitted in a through hole 47 of the fastening member 40 and is connected to a connecting member 48 embedded and fixed in the end plate 5. 50, 51
Is a hole for supplying and discharging hydraulic pressure inside the cylinder.
When hydraulic pressure is applied from 50, the inclined side surfaces 41 and 42 of the recess 43 of the fastening member 40 are fitted to the inclined surface 3b of the flange portion 3a of the body 3 and the inclined surface 5a of the end plate 5 as shown in FIG. When the upper and lower portions of the flange portion 3a of the body 3 and the end plate 5 are tightened and hydraulic pressure is supplied through the supply / discharge hole 51, the inclined side surface of the recess 43 of the tightening member 40 is formed.
41 and 42 are separated from the inclined surface 3b of the flange portion 3a of the body 3 and the inclined surface 5a of the end plate 5 as shown in FIG.

In FIGS. 1 to 4, reference numeral 55 denotes a fixed-size cutting mechanism for a processed product. Reference numeral 56 denotes a support base provided with bolts 57 in parallel with the end plate 5 at an appropriate interval. The base end of the bolt 57 is rotatably connected to a bracket 58 protruding from one side of the end plate 5 via a connecting pin 59 as shown in FIGS. Therefore, when the bolt 57 is removed, the support 56 rotates about the pin 59 as a fulcrum. Two rotary blades 61 are rotatably provided at a position slightly deviated from the rotation axis of the support base 59, and the sprockets on the shaft 62 of the rotary blade 61 are interlocked via a chain 63 or the like. A drive motor (drive member) 65 is provided on a shaft 62 via a coupling or the like.

As shown in FIG. 14, the drive motor 65 is rotated by being supplied with power from the power supply 64 when turned on by the switch SW, and stopped when turned off. The switch SW is controlled by a control circuit 66, and the control circuit 66 has a limit switch LS for detecting a temporary stop position of the rotary blade 61.
(See FIG. 3). Thus, the rotary blade 61 rotates at a high speed (a peripheral speed of 1 m / sec or more) under the control of the control circuit 66 (the time required for one rotation is 1 second). When the limit switch LS is actuated by the rotation of the rotary blade 61 and the contact with the limit switch LS after cutting the workpiece, the control circuit 66 receiving this detection signal outputs a stop signal to the switch SW, whereby the rotary blade 61 is temporarily stopped rotating. The set stop time (3) is set by a timer (not shown) incorporated in the control circuit 66.
After elapse of sec), the switch SW is turned on, the motor 65 is driven, and the rotary blade 61 is rotated again. By repeating the intermittent rotation by the rotary blade 61, the rotary blade 61 cuts the processing object to a fixed size. In order to increase the accuracy of the cut surface, it is desirable that the position of the rotary blade 61 be provided as close to the discharge holes 13 and 14 as possible.
In FIG. 3, O indicates the rotation center of the rotary blade 61, X indicates the rotation locus of the rotary blade 61, and Y indicates the temporary stop position of the rotary blade 61.
67 is a solution砕用projection provided on the inner surface of the body liner 15 immediately below the supply port 4 side, is provided in corresponding positions with the feed screw 20 _1, 20 _2.

Reference numeral 68 denotes a jacket (heating jacket) provided on the downstream side of the end plate 5 for heating the raw material with a heating medium (for example, heating oil). Semi-melt the plastic. 73 and 74 are a supply pipe and a discharge pipe for the heat medium. 71 is a cooling water inlet, 72
Is a thermocouple. Reference numeral 76 denotes a jacket (cooling jacket) for cooling the raw material by a refrigerant (for example, cooling water), which is located downstream of the heating jacket 68 and adjacent thereto. 77,78
Are a supply pipe and a discharge pipe of the refrigerant. In this embodiment, the heating and cooling jackets 68 and 76 are configured as follows. That is, the discharge holes 13 and 14 of the end plate 5 are formed by the cylindrical portions 81 protruding downstream from the end plates, and these cylindrical portions 81 and the cylindrical portions are formed on the outer peripheral side of the end plate 5 so as to surround these cylindrical portions.
An annular wall 82 that projects in the same direction as 81, and the annular wall 82 and the cylindrical portion
A large jacket body 85 is formed by the lid plate 83 arranged so as to connect the respective ends of 81, and the end plate 5 side is formed by a partition plate 86 arranged at an intermediate position in the axial direction of the jacket body 85. The heating jacket 68 and the cover plate 83 side are formed in the cooling jacket 76, respectively. In addition, rotating shafts 17 and 18
The end on the side of the supply port 4 penetrates the body 3 and is driven to rotate by a prime mover (not shown) such as a motor.

Next, the operation of the embodiment will be described. When the object to be processed is dropped into the feed zone of the screw 20 ₁ to 20 ₆ feed from the supply port 4, the feed screw on the rotary shaft 17, 18 the treatment was to be viewed first plane rotating in opposite directions to the outer side to each other is crushed by 20 _1, 20 ₂ a solution砕用protrusion 67. Crude after grinding, and further sends the transfer to the screw 20 ₁ to 20 ₆ by an end plate 5 side, compressed by the rotational force of the rotary shaft 17 during this time, crushed, and is milled by attrition砕板28. And end plate 5
, And is sequentially discharged from the discharge nozzle 33.If the object to be processed is a relatively long string-shaped object, it may be caught by the discharge nozzle or congested at a portion where the discharge nozzle 33 is not provided. is there. In such a case, the long string-shaped workpiece is scraped and cut by the scraping blade 24 of the scraping member 23 rotated by the rotating shafts 17 and 18,
After being finely divided, it is guided to the concave groove 25 and transferred to the discharge nozzle 33 side. At this time, the grooves 35, 36 are also provided on the opposing surface of the grinding plate 28.
The milling effect of the cooperation of the gap (about 5 mm in the illustrated case) between the concave groove 25 and the concave grooves 35 and 36 further enhances the grinding effect on the workpiece, and the discharge nozzle 33
The transfer to the side makes the discharge very smooth. Also,
In addition to generating internal friction in the fusible material and inducing self-heating, it can be efficiently softened and melted,
An efficient mixing action with the non-melt raw material is also performed, and sufficient volume reduction and solidification that does not cause bulk return after discharge can be realized.

When the object to be processed passes through the discharge nozzle 33, it is first heated by the heat medium supplied to the heating jacket 68 and then cooled by the refrigerant supplied to the cooling jacket 76. By the action, even an object whose melting is insufficient can be semi-melted. When the operation (operation) is completed, the semi-molten solid is solidified in the discharge nozzle 33. This must be softened before or during operation. At the beginning of the operation, the temperature of the cylindrical portion 81 itself is lowered, so it is necessary to heat the cylindrical portion 81 with a heat medium to make the flow in the discharge nozzle 33 smooth. Conversely, the cylinder 81 is heated by the self-heating of the plastic due to the self-heating of the plastic.At this stage, the supply of the heat medium is stopped, and the refrigerant is supplied to the cooling jacket 76 to cool it. The temperature of the object to be processed whose outer peripheral side is excessively heated can be made substantially uniform both at the outer peripheral side and at the center.
That is, when the temperature of the object subjected to the heating action of the heating jacket 68 was measured, the temperature of the central part of the object was about 100 to 110 ° C., and the temperature of the outer peripheral part was about 130 to 140 ° C. However, when subjected to the cooling action of the cooling jacket 76 by the refrigerant, the temperature of the outer peripheral portion was about 100 to 110 ° C., which was almost the same as that of the central portion. This cooling eliminated spikes.

The workpiece passing through the discharge nozzle 33 is cut into a fixed size by a rotary blade 61 driven intermittently at high speed. In this case, even if the object is not sufficiently cured, the cut edge is cut with high precision. Moreover, shape retention is high. Further, the cut edge does not drop due to the cooling of the outer peripheral portion. Therefore, the dimensional accuracy is greatly improved, and therefore, the filling rate in bagging is increased. In addition, since the rotary blade 61 temporarily stops after one rotation at a high speed, the fixed size of the melt does not become short, so that the subsequent handling is easy and the increase in the filling rate is suppressed. In addition, by bringing the rotary blade 61 closer to the discharge nozzle 33 side, the cut edge has higher accuracy.

[0018]

According to the first aspect of the present invention, when cutting, the rotating blade after cutting the raw material by high-speed rotation is temporarily stopped and intermittently rotated so as to re-rotate after a predetermined time. Unlike the conventional cutting method, the cut surface does not become oblique or torn, and the accuracy of the cut surface can be improved. Moreover,
An increase in the filling rate can be suppressed, and handling after cutting is also convenient. According to the second aspect of the present invention, the above effects can be realized by a simple device. According to the invention of claim 3, furthermore, such a cutting device can be applied to a twin-screw extruder to cut the raw material extruded by the extruder in the same manner.

[Brief description of the drawings]

FIG. 1 is a partially broken front view showing a twin-screw extruder according to an embodiment of the present invention.

FIG. 2 is a plan view of the above, partly omitted and partially broken.

FIG. 3 is a partially broken side view of the same.

FIG. 4 is a partially broken side view of the same.

FIG. 5 is a side view of the scraping member.

FIG. 6 is a side view of the upstream side surface of the scraping member.

FIG. 7 is a sectional view taken along line DD of FIG. 6;

FIG. 8 is a side view of a downstream side surface of the scraping member.

FIG. 9 is a partially enlarged view taken along line EE of FIG. 8;

FIG. 10 is a side view of the upstream side surface of the milling plate incorporated in the end plate.

FIG. 11 is a partially enlarged side view of FIG. 10;

FIG. 12 is a partial view taken along line F of FIG. 11;

13A and 13B are enlarged cross-sectional views of the hydraulic clamp mechanism, wherein FIG. 13A shows a tightened state, and FIG. 13B shows a state before tightening.

FIG. 14 is a schematic block diagram showing a drive control system of the rotary blade.

[Description of Signs] ₁ Twin-screw extruder 3 Body 4 Supply port 5 End plate 11 Hydraulic clamp mechanism 13, 14 Drain hole 15 Body liner 17, 18 Rotary shaft 20 _{1 to} 20 ₆ Feed screw 23 Scraping member 28 Grinding plate 30, 31 Discharge hole 33 Discharge nozzle 45 Hydraulic cylinder 61 Rotary blade 65 Drive motor (drive member) 66 Control circuit (control member) 67 Crushing projection 68 Heating jacket 73, 74 Supply and discharge pipes for heating medium 76 Cooling jacket 77, 78 Refrigerant supply and discharge pipes 81 Tube section 82 Annular wall 83 Cover plate 85 Jacket body 86 Partition plate

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) B29C 47/00-47/96 B26D 1/00-1/62 B29B 17/00-17/02

Claims (3)

(57) [Claims] When a rod-shaped raw material fed by a rotary screw of an extruder and discharged from a discharge hole is cut into a predetermined length by a rotary blade rotating at a high speed, rotation after cutting the raw material by rotation is performed. A method for cutting a raw material, comprising: temporarily stopping a blade, and intermittently rotating the blade after a predetermined period of time. 2. A rotary blade provided in the vicinity of a discharge hole of an extruder for cutting a rod-shaped raw material discharged from the discharge hole into a predetermined length, and a driving member for rotating the rotary blade at a high speed. And a control member for intermittently controlling the rotation of the drive member after the rotary blade has cut the raw material by rotation, and then re-rotating the drive member after a predetermined time. . 3. A body provided with a raw material supply port at an upper end on one end side and having an end plate having a plurality of discharge holes on the other end side, and rotatable in a direction facing the body. , A pair of rotating shafts, a feed screw provided on the rotating shaft, and a rod-shaped raw material provided near the discharge hole and discharged from the discharge hole at a predetermined length. In a raw material cutting device of a twin-screw extruder comprising a rotary blade and a driving member for rotating the rotary blade at high speed,
A raw material cutting device, comprising: a control member for controlling the rotation of the driving member intermittently so that the rotation is temporarily stopped after the rotary blade cuts the raw material by rotation, and then re-rotated after a predetermined time.