JPH0528028Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an extrusion molding machine having a T-die.

[Prior Art] Generally, this type of extrusion molding machine includes a T-die and a truck on which the T-die is mounted. In this type of extrusion molding machine, the carriage is configured to be able to reciprocate between a forward limit position and a backward limit position along a movement direction defined by a rail or the like. Therefore, the truck can move within the range of both limit positions and guide the T-die to the forming position. When the T-die is guided to the molding position by the movement of the trolley, the plasticized resin is extruded through the T-die in an extrusion direction that intersects the direction of movement of the trolley, forming a film. It is wound onto a take-up roll.

As mentioned above, when the T-die is used for film forming, as the width of the film becomes wider, it becomes difficult to form a film with a uniform thickness, and the non-uniformity of the film thickness, i.e. , unevenness in film thickness inevitably occurs. For this reason,
The drawback was that it adversely affected the appearance of the film.

In order to improve the negative effects caused by uneven film thickness, an extrusion molding machine has also been proposed in which the T-die is reciprocated in the above-mentioned movement direction within a range narrower than the film width to disperse areas where uneven thickness occurs. . In this type of extrusion molding machine, after the carriage is moved to a molding position, the carriage is reciprocated in the moving direction with the molding position as a reference. Therefore, the above-mentioned rocking is performed with a fixed reference position as an inverted position, and with a constant swing amplitude.
Note that the ends of the film extruded from the T-die in the width direction are usually trimmed to remove defective parts.

[Problems to be Solved by the Invention] This means that the T-die is placed in the same situation within the range of the above-mentioned reciprocating oscillation and at the period of the reciprocating oscillation. For this reason, the amount of uneven thickness deposited increases locally, and convex portions and concave portions corresponding to the amount of rocking movement appear in the film roll.

An object of the present invention is to provide an extrusion molding machine that can prevent the accumulation of uneven thickness within the range of reciprocating rocking and can further improve the winding appearance of the film.

[Means for Solving the Problems] According to the present invention, a T-die for extruding plasticized resin in the form of a film in a predetermined extrusion direction; An extrusion method that includes a cart capable of moving the T-die in a movement direction that intersects with the extrusion direction, and swings the T-die by reciprocating the cart in the movement direction within a range narrower than the film width. In the molding machine,
means for determining the range of reciprocating swing; means for measuring the time of reciprocating swing; and means for instructing switching of the reciprocating range when the reciprocating swing has been performed for a predetermined time; An extrusion molding machine having means for varying the swing range is obtained.

[Operation] In the present invention, since the reference position of the reciprocating swing of the cart and the T-die, that is, the reversal position of the swing, is changed over time, the accumulation of uneven thickness can be kept to a minimum.

[Example] Hereinafter, the present invention will be explained with reference to the drawings.

Referring to FIG. 1, the extrusion molding machine according to the present invention includes a truck 10 and a T-shaped body mounted on the truck 10.
It has a die 11. The trolley 10 is the rail 12
It is possible to travel in the left and right directions in the figure on the trajectory defined by . Therefore, in FIG. 1, the left-right direction in the figure is the moving direction of the truck 10. The range of movement of the truck 10 is limited by stoppers 13 and 14 provided at the right and left ends of the rail 12. On the other hand, a plasticized resin is supplied to the T-die 11, and the film is extruded in the vertical direction in the figure, that is, in the extrusion direction. Thus, the moving direction of the truck 10 intersects the film extrusion direction.

Referring to FIGS. 2 and 1, stopper 1
A forward limit plate 16 is provided near the stopper 14 along the rail 12 to determine the forward limit position of the truck 10, and on the other hand, near the stopper 14,
A rearward limit plate 17 is provided that determines the rearward limit position of the truck 10, and the truck 10 can actually travel between the plates 16 and 17.

Furthermore, the illustrated embodiment includes a first rocking plate pair constituted by a first and second plate 21 and 22 that define a range of reciprocating rocking, and the first rocking plate pair 21 and 22 refer to third and fourth plates 2 that are slightly shifted in the moving direction, that is, provided at offset positions.
A second rocking plate pair constituted by 6 and 27 is provided. The spacing between the first and second pairs of rocking plates defines the range of reciprocating rocking, and in this embodiment, the spacing between each pair is equal to each other. Further, the second pair of swinging plates 26, 2
7 is positioned on the outside of the first swing plate pair 21, 22 with respect to the rail 12.

On the other hand, the truck 10 is provided with a limit switch section 30 or a proximity switch at a position where it can come into contact with the above-described first and second rocking plate pairs 21, 22, and 26, 27. The limit switch section 30 has a first pair of switches provided corresponding to the first pair of swinging plates, and a second pair of switches provided corresponding to the second pair of swinging plates. . Of these, the first switch pair includes a first switch 31 that contacts the plate 21;
The second switch pair includes a second switch 32 in contact with plate 22, and a third switch 33 in contact with plate 26 and a fourth switch 34 in contact with plate 27.

The operation of the extrusion molding machine shown in FIGS. 1 and 2 will be explained with reference also to FIGS. 3 and 4. In FIG. 3, a control section within the truck 10 is shown to explain the operation of the truck 10.
The first to fourth switches 31 to 34 are connected to a switch control section 41, and the switch control section 41 controls the drive device 4 via a controller 42.
Connected to 3. The drive device 43 is used to drive a motor (not shown) of the truck 10 and the like.

In FIG. 4, the truck 10 has a rearward limit plate 1.
Travel from position 7 to switching position 46 at high speed,
When the switching position 46 is reached, the running speed of the truck 10 is switched to low speed. During this low-speed running, the switch 47 indicates that the forward limit plate 16 has been reached.
When detected, the trolley 10 stops. Next, under the control of the controller 42, a rocking operation is started as shown in FIG. 4A. As a result, the first and second switches 3
1 and 32 are placed in an operable state, and the truck 10 reciprocates back and forth in the moving direction between the switches 31 and 32, centering on the position of the forward limit plate 16. Specifically, the trolley 10 moves forward until it comes into contact with the plate 21 and the switch 31, and when it is detected that the switch 31 is turned on, the controller 4
2, the trolley 10 starts moving backward. As a result of the backward movement, when the switch 32 comes into contact with the plate 22 and turns on, the truck 10 stops moving backward and starts moving forward again. Thereafter, the trolley 10 repeats forward and backward movement by the same operation.

On the other hand, the controller 42 uses a timer built in the controller 42 to time the reciprocating swing described above.
Alternatively, it is monitored by a counter, and when a predetermined time T has elapsed, the controller 42 sends a switching instruction signal to the switch control section 41. Note that the predetermined time T can be varied between 0.05 seconds and 10 hours, and is usually selected to be several tens of minutes.

On the other hand, the controller 42 provides a drive signal to the drive device 43, and the drive device 43 causes the truck 10 to operate in an offset mode in which it reciprocates between the plates 26 and 27. At this time, the trolley 10 is the fourth one.
As shown in Figure B, the third and fourth switches 3
The controller 42 monitors the contact between the third and fourth plates 26 and 27, and the cart 10 swings back and forth between the third and fourth plates 26 and 27 for a predetermined time T. After the predetermined time has elapsed, the first
The second switches 31 and 32 are placed in an operable state, and the above-described operations are repeated thereafter.

As is clear from the above, the reciprocating rocking range is determined by each plate pair, and the controller instructs the switching of the reciprocating rocking time and rocking range. Furthermore, it is clear that the drive device changes the swing range in accordance with the swing range switching instruction.

[Effect] In the extrusion molding machine according to the present invention, by temporally changing the range of reciprocating oscillation, it is possible to suppress as much as possible unevenness in the thickness of the film extruded from the T-die, and to improve the winding shape of the roll. It is possible to eliminate the unevenness of the surface.

[Modifications of Embodiments] Although the embodiments described above have been described only in the case where two sets of switches are used in combination with two sets of plates, the present invention is not limited to this in any way. More sets of switches may be combined with more sets of plates to configure the offset range in multiple stages. Further, the swinging speed may be constant or may be a constant multiple of the film forming line speed. Further, the swing distance can be arbitrarily set by changing the position of the plate.

The swing distance and swing time during offsetting may be changed from the normal swing distance and time. Also, it is possible to change the swing range and swing time sequentially according to a program stored in the controller, for example, without using plates arranged along the rail. In this case, it is clear that the controller also operates as a means for determining the swing range.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a system including an extrusion molding machine according to an embodiment of the present invention, and FIG. 2 is a plan view showing a part of the extrusion molding machine system shown in FIG.
Fig. 3 is a block diagram for explaining the control of the extrusion molding machine according to the present invention, and Fig. 4 is a block diagram for explaining the operation of Figs. FIG. Explanation of symbols, 10...Dolly, 11...T-die, 12...Rail, 13, 14...Stopper, 16, 17...Forward limit and reverse limit plate,
21, 22...first plate pair, 26, 27...
...Second plate pair, 31-34...First to fourth
switch, 41... switch control section, 42...
Controller, 43... drive device.

Claims (1)

[Scope of utility model registration request] a T-die for extruding plasticized resin in the form of a film in a predetermined extrusion direction;
- having a trolley on which a die is mounted and capable of moving the T-die in a moving direction intersecting the extrusion direction, and swinging the trolley back and forth in the moving direction within a range narrower than the film width; According to
In an extrusion molding machine that swings a T-die, there is a means for determining the range of the reciprocating swing, and a means for measuring the time of the reciprocating swing, and when the reciprocating swing is performed for a predetermined time, the range of the reciprocating swing is determined. An extrusion molding machine comprising: means for instructing switching; and means for varying a reciprocating swing range in response to the switching instruction.