JP2002066990A - Cutting device for semi-solid synthetic resin sheet - Google Patents

Abstract

(57) [Problem] To reduce the production cost of a semi-solid synthetic resin sheet used for molding and to improve the transportability to a molding device. SOLUTION: A first cooling plate 23 of a cutting machine 20 is provided with a second cooling plate 25 in which a slit 25a is formed so as to be able to approach and separate, and a cutter supported by the second cooling plate so as to be movable in parallel with the slit. The head 30 is provided with a cutter 35 that enters the slit and a part of the outer periphery protrudes toward the first cooling plate. With the semi-solid synthetic resin sheet 15 extruded from the extrusion die 13 held between the cooling plates, the cutter head is moved and the semi-solid synthetic resin sheet is cut by the cutter. If the cutting machine is moved together with the semi-solid synthetic resin sheet, the cutting can be performed without stopping the extrusion of the semi-solid synthetic resin sheet. Cured portions are formed on both side edges of the obtained cut sheet of semi-solid synthetic resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semi-solid synthetic resin sheet cutting apparatus for cutting a semi-solid synthetic resin sheet continuously extruded from an extrusion die of an extruder.

[0002]

2. Description of the Related Art In a vacuum molding or stamping molding of a synthetic resin product, a semi-solid synthetic resin sheet cut to a predetermined size may be used as a material. Conventionally, such a semi-solid synthetic resin sheet is formed by cutting a semi-solid synthetic resin sheet continuously extruded from an extrusion die into a cut sheet by temporarily cooling and hardening the sheet to a predetermined size, and reheating immediately before molding. Used in a semi-molten state.

[0003]

However, according to the above-mentioned method, since the synthetic resin cut sheet cut to a predetermined size is cooled and hardened, it is necessary to reheat the cut sheet before molding. Therefore, since equipment and energy for reheating are required, there is a problem that manufacturing cost is increased.

In order to solve such a problem, a semi-solid synthetic resin sheet continuously extruded from an extrusion die is placed on a cutting table without being cured by cooling and cut by a cutting blade to form a cut sheet. Although it is conceivable to use it for molding, there is a problem that the semi-solid synthetic resin sheet adheres to the cutting table and the cutting blade, so that the cutting does not work well and cutting failure occurs. Further, since the semi-solid synthetic resin sheet is difficult to be held by the manipulator, there is also a problem that transportability to the molding apparatus is poor. An object of the present invention is to solve each of these problems.

[0005]

An apparatus for cutting a semi-molten synthetic resin sheet according to the present invention is an extruder for supplying a semi-molten synthetic resin to an extrusion die and extruding the same from the extrusion die as a continuous semi-molten synthetic resin sheet. And a cutting machine for cutting the semi-solid synthetic resin sheet. The cutting machine is provided with a cooling medium passage, and the semi-solid synthetic resin sheet which is extruded from the extrusion die and slidable on one side is slidable. A first cooling plate to be in contact with, a cooling medium passage provided, provided so as to be able to approach and separate from one side surface of the first cooling plate, and a slit penetrating in the thickness direction intersects the extrusion direction of the semi-molten synthetic resin sheet. A second cooling plate formed in the direction, a cutter head guided and supported by the second cooling plate so as to be movable in parallel with the slit and moved by a cutter feed actuator, and orthogonal to the slit. A second cooling plate which is supported by a cutter head rotatably around a line, is driven to rotate by a cutter actuator, enters a slit, and a part of the outer periphery projects from the second cooling plate toward the first cooling plate; Approaching the first cooling plate and abutting on the semi-solid synthetic resin sheet and sandwiching it between the first cooling plate and the cutter head is moved by the cutter feed actuator, and the semi-solid synthetic resin sheet is moved by the cutter. Is cut off. The portion of the semi-solid synthetic resin sheet that comes into contact with the first cooling plate and the second cooling plate is cooled and hardened more than the other portions, so that it does not stick to the cutter and the first cooling plate during cutting.

According to the invention of the preceding paragraph, the cutting machine further includes a moving base that is guided and supported so as to be movable in the same direction as the moving direction of the semi-molten synthetic resin sheet and is moved by a cutting machine feed actuator, The second cooling plate is attached to the moving base, and the cutting machine moves the semi-solid synthetic resin sheet to the first cooling plate and the second cooling plate while the moving base is moving at the same speed as the moving speed of the semi-solid synthetic resin sheet. It is preferable that the semi-solid synthetic resin sheet is cut between the cooling plates by moving the cutter provided on the cutter head.

The invention of the preceding two aspects is characterized in that the semi-solid synthetic resin sheet sandwiched between the two cooling plates except for a predetermined width centering on the slit is provided on one side of the second cooling plate which is in contact with the semi-solid synthetic resin sheet. A concave step is formed so that a slight gap is formed between the first cooling plate and the one side of the first cooling plate which is in contact with the semi-solid synthetic resin sheet, except for a range corresponding to a predetermined width of the second cooling plate. It is preferable to form the concave step so that a slight gap is formed between the semi-solid synthetic resin sheet sandwiched between the plates.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The apparatus for cutting a semi-molten synthetic resin sheet of this embodiment is an extruder 11 that supplies a synthetic resin in a molten state to an extrusion die 13 and extrudes it as a semi-molten synthetic resin sheet 15, and is continuously extruded from the extrusion die 13. Cutting machine 2 for cutting the semi-solid synthetic resin sheet 15
0.

As shown mainly in FIGS. 1 and 2, an extruder 11 is fixed on a first bed 10 and heats a synthetic resin material supplied from a hopper 14 to extrude from a supply pipe 12 into a plastic semi-molten state. It is supplied to the die 13 and extruded from the extrusion die 13 as a continuous semi-solid synthetic resin sheet 15 in the X direction. The extruded semi-molten synthetic resin sheet 15 has an MFR (melt flow rate, melt flow rate) of a little less than 1 and is not immediately deformed by its own weight, but the plasticity required for vacuum forming and stamping molding is as follows. Have.

As shown in FIGS. 1 to 4, the cutting machine 20
A first cooling plate 23 formed of an elongated rectangular thick plate; and a second cooling plate 2 formed of a thick plate having the same contour shape as the first cooling plate 23 and provided on the upper side surface of the first cooling plate 23 so as to be able to approach and separate therefrom.
5 and a moving base 2 for supporting the cooling plates 23 and 25.
1, a cutter head 30 movably provided on the second cooling plate 25, and a circular cutter 35 rotatably supported by the cutter head 30. The movable base 21 is formed of a rectangular thick plate that is elongated in a direction perpendicular to the X direction, and a pair of X-direction rails fixed parallel to each other on a second bed 16 fixedly arranged with respect to the first bed 10. 17, the semi-solid synthetic resin sheet 15 is guided and supported movably in the same X direction as the moving direction of the semi-solid synthetic resin sheet 15, and is advanced and retracted by a cutting machine feed motor (both not shown) via a feed screw.

As shown mainly in FIGS. 1 to 3, the first cooling plate 23 has a length in a longitudinal direction orthogonal to the X direction larger than the lateral width of the semi-molten synthetic resin sheet 15.
Through the pair of support legs 22 provided on both sides, the semi-solid synthetic resin sheet 15 extruded and moved from the first cooling plate 23 has a height at which the sheet 15 naturally comes into sliding contact with the upper surface of the first cooling plate 23. And is fixed on the moving base 21. First cooling plate 2
A cooling medium passage 24 is formed in the cooling medium passage 3, and one end of the cooling medium passage 24 is connected to a cooling water supply pipe 24a, and the other end is connected to a cooling water discharge pipe 24b.

The moving base 21 is longer than both the cooling plates 23 and 25, and a pair of brackets 27 are fixed to both ends of the moving base 21 outside the first cooling plate 23 and stand up. I have. The upper end of each bracket 27 is bent inward to provide a lifting cylinder 26, respectively.
Both ends of the second cooling plate 25 are fixed to distal ends of piston rods 26 a extending downward of each lifting cylinder 26. By simultaneously operating the lifting cylinders 26, the second cooling plate 25 moves in the vertical Z direction perpendicular to the X direction and the Y direction, and moves closer to and away from the upper surface of the first cooling plate 23. In the center of the second cooling plate 25 in the X direction, a slit 25a extending in the Y direction orthogonal to the X direction is formed to penetrate in the thickness direction, and the length of the slit 25a is larger than the width of the semi-molten synthetic resin sheet 15. Is big. Second cooling plate 25
Inside the cooling medium passage 28, a cooling water supply pipe 28a is connected to one end of the cooling medium passage 28, and a cooling water discharge pipe 28b is connected to the other end.

As shown in FIGS. 1 to 4, the slit 25a
The slit 25a is formed on the upper surface of the second cooling plate
A cutter head 30 is guided and supported on a pair of Y-direction rails 29 fixed in parallel with the cutter head 30. Both slits 25a
A feed screw 32 rotatably supported in a groove 25b formed in the second cooling plate 25 between the cutter head 3
0, the feed nut 31 fixed to the lower side is screw-engaged,
The feed screw 32 is driven by the cutter feed motor 33 (see FIG. 4).
Is driven to reciprocate, so that the cutter head 30
Reciprocated in the direction. The slit 25a is parallel to the lower surface of the second cooling plate 25 which is in contact with the semi-solid synthetic resin sheet 15.
The cutter head 30 is rotatable about a rotation axis orthogonal to the
A circular cutter 35 having a knife-shaped blade formed all around is coaxially attached to the distal end of the cutter shaft 34 supported by the cutter shaft 34, and is rotationally driven by a cutter motor (not shown) incorporated in the cutter head 30. You. This circular cutter 35
A part of the outer periphery of the second cooling plate 25 enters the slit 25a and projects from the second cooling plate 25 toward the first cooling plate 23. Comes close to the first cooling plate 23, abuts the semi-solid synthetic resin sheet 15, and sandwiches it between the first cooling plate 23, and the cutting edge of the outer periphery of the circular cutter 35 approaches the first cooling plate 23. But no contact.

Next, the operation of the above embodiment will be described. During the following operation, the cooling water is always supplied to the cooling medium passages 24 and 28 through the first cooling plate 23 and the second cooling plate 25.
(For example, the first cooling plate 23 is 60 to 80
° C, the second cooling plate 25 is 20 to 30 ° C). First, at the start of the operation, the entire cutting machine 20 is set to the standby position shown in FIG. 1, the cutter head 30 is set to the standby position shown in FIGS. 3 and 4, and the second cooling plate 25 is set as shown in FIGS. Is separated from the first cooling plate 23 by the lifting cylinder 26. In this state, when the extruder 11 is operated and the semi-solid synthetic resin sheet 15 is extruded from the extrusion die 13, the semi-solid synthetic resin sheet 15 becomes as shown in FIG. Excluding) cooling plates 2
3 and 25, the first cooling plate 23 is slid while slightly abutting on the upper surface thereof. In this state, the semi-solid synthetic resin sheet 15 is only partially contacted with the first cooling plate 23 and the contact time is short, so that the first cooling plate 23 is slightly cooled.

At the beginning of the operation, the front end of the semi-molten synthetic resin sheet 15 has an irregular shape. For this, the entire cutting machine 20 is moved in the X direction at the same moving speed as the semi-molten synthetic resin sheet 15 by the cutting machine feed motor, the circular cutter 35 is rotated, and the second cooling plate 25 is lowered by the lifting cylinder 26. The first cooling plate 23 is brought close to the semi-molten synthetic resin sheet 15 and is brought into contact with the semi-solid synthetic resin sheet 15 at a light pressure (for example, 0.01 to 0.05 kg / cm 2) that does not substantially deform the sheet in the thickness direction. It is sandwiched between the cooling plate 23. In this state, the first and second
Since the cooling plates 23 and 25 press a certain part of the semi-solid synthetic resin sheet 15 with a certain pressure, the part of the semi-solid synthetic resin sheet 15 is brought into full contact with both the cooling plates 23 and 25 and gradually comes into contact therewith. Cooled and cured. In the state where the first and second cooling plates 23 and 25 are moving together while holding a certain portion of the semi-solid synthetic resin sheet 15 in this manner, the cutter head 30 is moved in the Y direction from the standby position by the cutter feed motor 33. The first and second cooling plates 2 of the semi-solid synthetic resin sheet 15 are moved by the rotating circular cutter 35.
The portion sandwiched by 3, 25 is cut. Since this portion of the semi-solid synthetic resin sheet 15 is cooled and hardened as described above, it is not adhered to the circular cutter 35 and the first cooling plate 23 at the time of cutting, and the cutting is easily performed. After the cutting is completed, the second cooling plate 25 is raised by the elevating cylinder 26 to be separated from the first cooling plate 23, and the second cooling plate 25 is separated from the circular cutter 35 of the portion hardened and cooled by the first and second cooling plates 23 and 25. The cut portion including the tip portion is removed, and the entire cutting machine 20 and the cutter head 3 are driven by the cutting machine feed motor and the cutter feed motor 33.
If 0 is returned to each standby position, the state shown in FIG. 1 is obtained. In this state, the front end of the semi-solid synthetic resin sheet 15 is cut at a right angle, and the front end edges thereof correspond to a width approximately half the length of the first and second cooling plates 23 and 25 in the X direction. Except that the hardened portion 15a in the range A is formed, similarly to the above-described operation start, the first cooling plate 23 is slid while slightly abutting on the upper surface thereof, and the semi-solid synthetic resin sheet 15 is slid.
Is only slightly cooled by the first cooling plate 23.

The semi-solid synthetic resin sheet 15 is
As shown in FIG. 1, the distance between the tip of the semi-solid synthetic resin sheet 15 and the circular cutter 35 is a predetermined length L.
Then, the entire cutting machine 20 is moved again in the X direction at the same moving speed as the semi-molten synthetic resin sheet 15 by the cutting machine feed motor, and the second cooling plate 25 approaches the first cooling plate 23 by the lifting cylinder 26. Then, the sheet is brought into contact with the semi-solid synthetic resin sheet 15 and sandwiched between the first cooling plate 23 and the above-mentioned pressure. And, as described above, the cutter feed motor 33
The cutter head 30 is moved from the standby position in the Y direction, and the portion of the semi-molten synthetic resin sheet 15 which is sandwiched and cooled by the first and second cooling plates 23 and 25 is cooled and cured.
Cutting is performed by the rotating circular cutter 35. After the cutting is completed, the second cooling plate 25 is raised by the elevating cylinder 26 to be separated from the first cooling plate 23, and the cut sheet 15A cut from the semi-solid synthetic resin sheet 15 as shown in FIG. Next, as described above, when the entire cutting machine 20 and the cutter head 30 are returned to the respective standby positions by the cutting machine feed motor and the cutter feed motor 33, the state shown in FIG. 1 is obtained. By repeating this, a cut sheet 15A made of a semi-solid synthetic resin sheet having a predetermined length L is sequentially obtained.

According to the above-described embodiment, the extruder 11
Sheet 15A cut from semi-solid synthetic resin sheet 15 continuously extruded from extrusion die 13
Can be used for molding such as vacuum molding and stamping molding without the need for reheating, since it remains in a semi-molten state except for the hardened portions 15a on the front and rear side edges. Therefore, equipment and energy for reheating are not required, so that manufacturing costs can be reduced. The first and second cooling plates 23, 25 of the semi-solid synthetic resin sheet 15 are also provided.
Is hardened as described above, so that the portion is not adhered to the circular cutter 35 and the first cooling plate 23 at the time of cutting, and the cutting is easily performed.
Further, the cut sheet 15A of the above-described embodiment includes:
As shown in FIG. 5, on both side edges, a range A corresponding to approximately half the width of the first and second cooling plates 23 and 25 in the X direction is provided.
Of the cut sheet 1 is formed.
5A can be easily transported to the molding apparatus by holding both hardened portions 15a with the manipulator 40 (see FIG. 5).

In the embodiment described above, the cutting machine 20
In the state where the movable base 21 is guided and supported so as to be movable in the same X direction as the moving direction of the semi-molten synthetic resin sheet 15, and the cutting machine 20 is moved in the X direction at the same moving speed as the semi-molten synthetic resin sheet 15, The semi-solid synthetic resin sheet 15 is sandwiched between the first and second cooling plates 23 and 26 to form a circular cutter 35.
According to this, the semi-solid synthetic resin sheet 15 can be cut without temporarily stopping the extrusion of the semi-solid synthetic resin sheet 15, so that the productivity of the cut sheet 15A is improved. be able to.
However, the present invention is not limited to this.
In this case, the cutting of the semi-solid synthetic resin sheet 15 is performed by the extruder 1.
1 may be performed in a state where the extrusion of the semi-solid synthetic resin sheet 15 is temporarily stopped.

In the above-described embodiment, the first cooling plate 23 and the second cooling plate 25 are sandwiched with a pressure that does not substantially deform the semi-solid synthetic resin sheet 15 in the thickness direction. This clamping pressure is applied to the semi-solid synthetic resin sheet 15.
May be changed so that the thickness of the hardened portions 15a formed on both side edges of the cut sheet 15A does not hinder the holding by the manipulator 40.

Further, in the above-described embodiment, the surfaces of the first cooling plate 23 and the second cooling plate 25 facing each other are each one plane, but contact the semi-solid synthetic resin sheet 15 of the second cooling plate 25. On the lower surface, the semi-solid synthetic resin sheet 1 sandwiched between the cooling plates 23, 25 except for a range of a predetermined width M (see FIG. 1) centered on the slit 25a.
5 to form a concave step so that some gap is created,
On the upper side surface of the first cooling plate 23 which is in contact with the semi-solid synthetic resin sheet 15, except for the range corresponding to the predetermined width M of the second cooling plate 25, the semi-molten material sandwiched between the two cooling plates 23, 25. A concave step may be formed so that a slight gap is formed between the synthetic resin sheet 15 and the synthetic resin sheet 15. In this way, the range of the semi-solid synthetic resin sheet 15 that is cooled and hardened by contacting the first cooling plate 23 and the second cooling plate 25 is only within the predetermined width M, and is therefore formed on both sides of the cut sheet 15A. The width of the range A of the cured portion 15a is half of the predetermined width M. By appropriately selecting the predetermined width M, the widths of the hardened portions 15a on both sides of the cut sheet 15A are set to the minimum necessary values without changing the widths of the first cooling plate 23 and the second cooling plate 25, The retention of the cut sheet 15A can be improved.

In the above embodiment, the first cooling plate 23
Although the upper side surface is a flat plane, an escape groove for preventing the cutting edge of the circular cutter 35 from contacting the first cooling plate 23 may be provided. The circular cutter 35 according to the above-described embodiment cuts the semi-solid synthetic resin sheet 15 by a sharp wedge action of a knife-shaped blade formed on the outer periphery.
The first cooling plate 23 is formed with a groove or a slit lightly contacting the side surface of the cutting edge portion on the outer periphery of the circular cutter 35 by increasing the amount of projection downward from the second cooling plate 25. The semi-solid synthetic resin sheet 15 may be cut by a shearing action by the cooperation of the groove and the slit of the first cooling plate 23. Alternatively, the circular cutter 35 may have a circular saw shape.

In the above embodiment, the second cooling plate 25
Is formed in the direction orthogonal to the X direction, but depending on the use of the cut sheet 15A, the slit 2
5a may be formed in a direction crossing the X direction at an angle other than a right angle.

[0023]

According to the present invention, a semi-solid synthetic resin sheet continuously extruded from an extrusion die by an extruder is cut into a cut sheet before being cooled and hardened. Is unnecessary. Therefore, equipment and energy for reheating are not required, so that manufacturing costs can be reduced. Further, the portion of the semi-solid synthetic resin sheet that contacts the first cooling plate and the second cooling plate is cooled and hardened more than the other portions, and is not adhered to the circular cutter and the first cooling plate during cutting. Cutting is easily performed and productivity can be improved. Furthermore, since the portions cooled by the first cooling plate and the second cooling plate become both side edges of the cut sheet, it is easy to hold this portion by a manipulator or the like, thereby making it easy to transport to a molding apparatus. Can be improved.

In the invention described in the preceding paragraph, the cutting machine moves the semi-solid synthetic resin sheet between the first cooling plate and the second cooling plate while the moving base is moving at the same speed as the moving speed of the semi-solid synthetic resin sheet. According to the pinching, the circular cutter provided on the cutter head is moved to cut the semi-molten synthetic resin sheet. Since the molten synthetic resin sheet can be cut, the productivity of the cut sheet can be further improved.

Further, in the invention of the preceding two aspects, a concave step is formed on one side of the second cooling plate abutting on the semi-solid synthetic resin sheet, except for a predetermined width centered on the slit, and the first cooling plate is formed. The second side is in contact with the semi-solid synthetic resin sheet of
According to the one in which the concave step portion is formed except for the range corresponding to the predetermined width of the cooling plate, the range of the cooled and hardened portion formed on both side edges of the cut sheet can be minimized, so that The yield of the molten synthetic resin sheet can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing the entire structure of an embodiment of a cutting device for a semi-molten synthetic resin sheet according to the present invention.

FIG. 2 is a cross-sectional view of a main part showing an operation state of the embodiment shown in FIG.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 1;

FIG. 4 is a plan view showing a main part of the embodiment shown in FIG. 1;

FIG. 5 is a perspective view showing a cut sheet cut from a semi-solid synthetic resin sheet according to the embodiment shown in FIG. 1;

[Description of Signs] 11 ... Extruder, 13 ... Extrusion die, 15 ... Semi-molten synthetic resin sheet, 20 ... Cutting machine, 21 ... Moving base, 23 ... First
Cooling plate, 24 ... cooling medium passage, 25 ... second cooling plate, 25
a: slit, 28: cooling medium passage, 30: cutter head, 33: cutter feed actuator (cutter feed motor), 35: cutter (circular cutter), M: predetermined width.

Claims (3)

[Claims] 1. An extruder for supplying a synthetic resin in a semi-molten state to an extrusion die and extruding the same from the extrusion die as a continuous semi-solid synthetic resin sheet, and a cutting machine for cutting the semi-solid synthetic resin sheet. The cutting machine is provided with a cooling medium passage, a first cooling plate on which the semi-solid synthetic resin sheet that is extruded from the extrusion die and moves is slidably contacted on one side, and a cooling medium passage is provided. A second cooling plate, which is provided so as to be able to approach and separate from the one side surface of the first cooling plate and has a slit penetrating in the thickness direction in a direction intersecting with the extrusion direction of the semi-molten synthetic resin sheet; A cutter head guided and supported by the second cooling plate movably in parallel with the slit and moved by a cutter feed actuator; and a cutter head rotatable about an axis orthogonal to the slit. The cutter is supported by a cutter head, is driven to rotate by a cutter actuator, enters the slit, and has a part of an outer periphery protruding from the second cooling plate toward the first cooling plate, and the second cooling plate is provided with the second cooling plate. 1
The cutter head is moved by a cutter feed actuator while approaching the cooling plate and abutting on the semi-solid synthetic resin sheet and sandwiching it between the first cooling plate, and the semi-solid synthetic resin is moved by the cutter. An apparatus for cutting a semi-solid synthetic resin sheet, which cuts a resin sheet. 2. The cutting machine further includes a moving base that is guided and supported so as to be movable in the same direction as the moving direction of the semi-molten synthetic resin sheet and is moved by a cutting machine feeding actuator. The second cooling plate is attached to the moving base, and the cutting machine moves the semi-solid synthetic resin sheet to the second position while the moving base is moving at the same speed as the moving speed of the semi-solid synthetic resin sheet. The semi-solid synthetic resin sheet according to claim 1, wherein the semi-solid synthetic resin sheet is sandwiched between a first cooling plate and a second cooling plate, and the cutter provided on the cutter head moves to cut the semi-solid synthetic resin sheet. Cutting equipment. 3. The semi-solid synthetic resin sheet sandwiched between the two cooling plates on one side of the second cooling plate, which is in contact with the semi-solid synthetic resin sheet, except for a predetermined width centered on the slit. A concave step is formed so that a slight gap is formed between the first cooling plate and the side surface of the first cooling plate that contacts the semi-solid synthetic resin sheet. The semi-solid synthetic material according to claim 1 or 2, wherein a concave step is formed so that a slight gap is formed between the semi-solid synthetic resin sheet sandwiched between the cooling plates. Cutting machine for resin sheet.