JPH0717532U - Die gate breaker plate - Google Patents

Abstract

(57) [Abstract] [Purpose] To obtain molten resin with uniform viscosity from the resin melting device.
It is intended to supply a breaker plate of a die gate which can be supplied to a die. [Structure] The inner pipe of the die gate connected between the first supply pipe 2 having a large inner diameter on the resin melting device side and the second supply pipe 3 having a small inner diameter on the T die side is a tapered pipe 5. The breaker plate 6 inserted into the tapered pipe 5 from the first supply pipe 2 side of the tapered pipe 5 is a conical body with a collar, and a large number of through pores 6a are formed in parallel along the center line of the conical body. It is what

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an extruder for producing a resin film from a molten resin.

[0002]

[Prior art]

 A large-diameter first supply pipe 2 and a small-diameter second supply pipe 3 on the resin-melting device side are connected by being provided in the middle of a resin-supplying pipe that connects a resin-melting device of an extrusion device for manufacturing a resin film and a T-die. In addition, as shown in FIG. 4, the die gate 1 which changes its direction from the horizontal direction to the downward direction uses a breaker plate 8 which is a flat disk and is provided with a large number of small holes dispersed throughout. Was there.

[0003]

[Problems to be solved by the device]

 However, since the tapered pipe 5 is provided from the position of the breaker plate 8 to the second supply pipe 3, the flow of the molten resin is fast in the central portion and slows toward the wall surface side. Therefore, even if the amount of resin discharged from the extruder is constant, the resin is supplied to the second supply pipe 3 in a state in which its viscosity is varied, that is, the viscosity is constantly changing. When the rotation of the extruder is low, the resin on the wall surface becomes even slower than the flow stagnating, and the constant temperature of heating from the outer surface is added to that extent, resulting in an overheat, resulting in resin viscosity. Becomes more and more low-viscosity side. When such a molten resin having a non-uniform viscosity is extruded from the T-die 4, uneven thickness 9a occurs in the flow direction of the film 9 as shown in FIG. 3, which is a major cause of defective production. The yield will be reduced.

Conventionally, the above is unavoidable in processing, and the rotation of the screw is increased or decreased until the defective resin at the time of low rotation of the extruder is completely discharged at the time of processing. It produces by discharging stagnant resin. The amount of discharged loss resin is enormous.

An object of the present invention is to solve the above problems and provide a breaker plate capable of manufacturing a film 9 having a uniform thickness.

[0006]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, in a device for producing a resin film from a molten resin, the resin melting device is provided in the middle of a resin supply pipe connecting between the resin melting device and a T die 4 for extruding a film-shaped resin. The first supply pipe 2 having a large inner diameter on the T side and the second supply pipe 3 having a small inner diameter on the T die 4 side are tapered in the inner diameter in the tapered shape of the tapered pipe 5. The breaker plate 6 which is provided in the taper pipe 5 from the large diameter part of the inner pipe connected to the pipe 2 and filters the unmelted resin block is a cone with a collar, which is parallel to the center line of this cone. A large number of through pores are formed.

[0007]

[Action]

 As described above, in the portion where the temperature of the molten resin is likely to rise on the wall of the tapered pipe 5, the flow velocity is increased to prevent the influence of the temperature rise, and the molten resin having a uniform temperature and a uniform viscosity is supplied to the T die. By doing so, the film 9 having no thickness unevenness 9a is manufactured.

[0008]

【Example】

 FIG. 1 is a cross-sectional view of a taper pipe part equipped with a breaker plate of the present invention and FIG. 2 is a cross-sectional view of a die gate part connected to a first supply pipe and a second supply pipe.

As shown in FIG. 2, a die gate 1 is provided in the middle of a resin supply pipe connecting between a resin melting device (not shown) and a T die 4 for extruding a film-shaped resin. The die gate 1 is a vertical pipe having a horizontal pipe on the inlet side and a downward pipe on the outlet side. The vertical pipe is connected to a second supply pipe 3 having a small inner diameter which is connected to a T die 4, and the horizontal pipe is a thin pipe. (2) A taper pipe 5 is formed so as to connect the supply pipe 3 and the first supply pipe 2 having a large inner diameter from the resin melting device.

A screen 7 and a breaker plate 6 are sandwiched between the taper pipe 5 and the first supply pipe 2 from the first supply pipe 2 side so as to extend over the entire cross section of the supply pipe.

The breaker plate 6 is a conical body with a collar, the first supply pipe 2 side is a flat surface, the taper pipe 5 side is a conical body, and as shown in FIG. The breaker plate 6 is small in size, and the cone portion of the breaker plate 6 is large. The breaker plate 6 is deeply embedded inside the tapered tube 5, and a large number of through-holes 6a are dispersed in parallel along the center line of the cone body. It is arranged and drilled.

Therefore, the distance between the inner surface of the tapered tube 5 and the outer surface of the conical body becomes larger toward the tip of the conical body, and the cross-sectional area perpendicular to the center line is substantially the same at each position. Has been done.

Next, the operation of the breaker plate 6 of the present invention will be described. The molten resin that has been pressure-fed by the first supply pipe 2 from a resin melting device (not shown) filters undissolved resin lumps on the screen 7, and only the molten resin passes through the through holes 6a of the breaker plate 6 and the tapered pipe 5 Supplied within.

In this case, the gap between the tapered tube 5 and the cone of the player plate 6 is narrower toward the root of the cone, and the number of the through pores 6a is larger as the circumference is larger. The flow velocity of the molten resin becomes higher, and the molten resin is less likely to stagnate on the inner surface of the tapered tube 5.

This means that the temperature variation of the molten resin flowing into the second supply pipe 3 is small and the viscosity of the molten resin is kept uniform.

As a result, the occurrence of non-uniformity in the flow direction of the resin film extruded from the T die 4 as shown in FIG. 3 is suppressed.

[0017]

[Effect of device]

 As described above, by using the conical breaker plate 6 that infiltrates into the tapered tube 5 of the die gate 1, it is possible to accelerate the flow of the molten resin on the wall surface of the tapered tube 5, As a result, the molten resin is unlikely to stagnate on the wall surface, and the viscosity of the molten resin supplied to the T die 4 does not change at each location.

Since the molten resin having a uniform viscosity is supplied, the film extruded from the T die 4 can be a homogeneous and high-quality film.

It is possible to manufacture a high-quality film only by replacing the conventional die gate 1 with the breaker plate 6 of the present invention without modifying it.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a tapered tube portion equipped with a breaker plate of the present invention.

FIG. 2 is a cross-sectional view of a die gate portion connected to a first supply pipe and a second supply pipe.

FIG. 3 is an explanatory diagram of a film in a defective state extruded from a T die.

FIG. 4 is a cross-sectional view of a taper tube portion equipped with a conventional breaker plate.

[Explanation of symbols]

 1 Die Gate 2 First Supply Pipe 3 Second Supply Pipe 4 T Die 5 Tapered Pipe 6 Breaker Plate 6a Through Pores

Claims (1)

[Scope of utility model registration request] 1. An apparatus for producing a resin film from a molten resin, which is provided in the middle of a resin supply pipe connecting from the resin melting apparatus to a T die for extruding a film-shaped resin, and has a large inner diameter on the resin melting apparatus side. In the die gate of the tapered pipe in which the inner diameter is tapered to connect between the first supply pipe and the second supply pipe having a small inner diameter on the T-die side, a large diameter portion of the inner pipe connected to the first supply pipe The breaker plate, which is provided in the tapered tube to filter the unmelted resin block, is a cone with a collar, and a large number of through pores are formed in parallel along the center line of the cone. A breaker plate for a die gate.