JPH0952272A - Band-like matter extruding variable gage head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently manufacture a band-like matter having partly different thickness. SOLUTION: A band-like matter-extruding variable gage head 10 is mounted at the end of an extruder 12. The head 10 has a fixed upper head plate 20A and a lower head plate 20B vertically moving by a cylinder 28. Rubber material 16 fed from the extruder 12 is extruded between the plate 20A and plate 20B to become a band-like material. Since the plate 20B is moved to be able to alter the interval between the plate 20A and the plate 20B, the band-like material having partly different thickness can be efficiently manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gauge variable head for extruding a band, and more particularly to a gauge variable head for extruding a band capable of varying the thickness of the band.

[0002]

2. Description of the Related Art Belts such as a tread portion of an automobile tire and a cap rubber of a rubber crawler are generally manufactured by an extruder.

The raw rubber material inserted into the cylinder of the extruder is continuously extruded with a constant thickness from the hole of the die attached to the tip of the extrusion head by the rotation of the screw.

[0004]

In order to make a cap rubber for a rubber crawler, as shown in FIG. 8, an annular body 102 is made of a raw rubber strip 100 having a constant thickness, which is shown in FIG. When trying to perform the circle heating with the simple vulcanizer 104, the thickness of the joint portion 106 (the strip 10
Since the thickness is twice the thickness of 0), there is a problem that the rubber in the thickened portion protrudes from the mold 110 of the vulcanizer 104 and is damaged. In addition, the jointed part has a high rubber density in the product, and
Since the product gauge is also thick, it is not preferable in terms of quality.

In order to solve this problem, a method is conceivable in which the end portions to be joined are made thin and the joints are made.

Conventionally, as a method of partially reducing the wall thickness of the end portions of the strip-shaped article, as shown in FIG. 10, the strip-shaped articles 112 having the same thickness are laminated to reduce the number of laminated layers at both ends, or As shown in FIG. 11, the strip 114 and the strip 116 having different thicknesses had to be added. Therefore, the manufacturing process is complicated and the productivity is not good.

In view of the above facts, it is an object of the present invention to provide a gauge variable head for extruding a strip, which can efficiently produce a strip having a thin end portion.

[0008]

According to a first aspect of the present invention, there is provided a variable gauge for strip extrusion for determining the extrusion shape of a strip extruded by an extruder, comprising a pair of opposed die members. It is characterized in that at least one of the pair of mouthpiece members is provided movably in a direction in which it comes into contact with and separates from the other opposite mouthpiece member, and the band-shaped material is pushed out from between the pair of mouthpiece members.

The invention described in claim 2 is the same as claim 1.
The gauge-variable head for strip-shaped material extrusion according to [4] is characterized by comprising drive means for moving the mouthpiece member.

In the variable gauge for strip-shaped material extruding according to the first aspect, since the distance between the pair of die members can be varied, the thickness of the strip-shaped material can be varied during extrusion.

For example, in the case where a predetermined size is formed at both end portions in the longitudinal direction of a band-shaped material and the thin-walled portions are jointed to form an annular material having a constant thickness, first, the gap between the die members is set. And extrude the strip by the joint length, then widen the gap between the die members and extrude a predetermined amount of the strip, and finally narrow the gap between the die members and extrude the strip by the joint length to cut the strip. To do.

After that, the annular parts can be formed by superimposing the thin-walled parts at both ends of the band-like parts and jointing them. Here, since the thin portions of the belt-like material are overlapped to perform the joint, the thickness of the annular material can be made constant.

As described above, the wall thickness of both end portions can be reduced only by changing the interval between the die members, so that the production efficiency is high as compared with the method of laminating a plurality of strips or adding them.

In addition, the thickness of the strip can be freely changed not only by reducing the thickness at both ends but also by reducing the thickness of the central portion. Further, the thickness can be gradually increased or decreased.

In the variable gauge for strip extrusion according to the second aspect, the mouthpiece member is moved by the driving means.
Therefore, the movement of the base member is easy. A hydraulic cylinder, a feed screw mechanism, or the like can be used as the driving means.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a gauge variable head 10 for extruding a belt-like article according to the present invention will be described with reference to FIGS.

As shown in FIG. 1, a gauge variable head 10 for extruding a belt-shaped article of this embodiment is a cylinder 1 of an extruder 12.
The extruded material 16 inserted into the strip 4 is rotated by the rotation of a screw (not shown), and the gauge variable head 10 for strip extrusion is
It has a structure in which it is pushed out from the extrusion port 18 toward the arrow F direction.

As shown in FIG. 2, the arrow F at the extrusion port 18
On the direction side, the upper cap plate 20A that determines the shape of the product
And the lower cap plate 20B is arranged.

As shown in FIGS. 2 and 3, the upper mouthpiece plate 20A is fixed to the main body block 22 of the strip variable gauge 10 for extruding the belt-like member by a bolt or the like (not shown).

On the other hand, the lower cap plate 20B is fixed to the slide block 24 with bolts 26. The slide block 24 is attached to a piston rod 30 of a cylinder 28 attached to the main body block 22, and is movable in the vertical direction (arrow U direction and arrow D direction in the drawing) by a predetermined amount. In addition, in the cylinder 28,
A displacement sensor 40 for detecting the amount of displacement of the piston rod 30 is attached.

As shown in FIG. 2, the slide block 24
The upper base plate 20A and the lower base plate 20
A roller 24A that supports the lower surface of the strip 42 extruded from between B and B is rotatably provided, and the extruded strip 42 is located on the arrow F direction side of the upper mouth plate 20A and the lower mouth plate 20B. A roller conveyer 33 that conveys is disposed.

On the other hand, a slide member 32 on which the slide block 24 slides and a slide member 34 on which the lower cap plate 20B slides are attached to the side surface of the body block 22 on the arrow F direction side. Slide members 32, 34
Are provided to obtain stable slippage, and in particular, the slide member 34 serves as a seal for preventing rubber from leaking from between the slide member 34 and the lower cap plate 20B.

In the direction of arrow F of the slide block 24,
A holding cylinder 36 is arranged. The holding cylinder 36 is provided on the body block 22 via a frame (not shown).
It is fixed to.

The piston rod of the holding cylinder 36 moves in the directions of arrow F and arrow B,
A roller 38 is rotatably attached to the tip.

As shown in FIGS. 1 to 3, a fixed length cutting machine 44 for cutting the belt 42 is attached to the upper portion of the main body block 22 in the direction of arrow F.

The fixed length cutting machine 44 is an upper base plate 20A.
A cutter 44A that is in contact with the front surface of the machine and a cylinder 44B that drives the cutter 44A in the vertical direction are provided.

The roller conveyor 33 and the extruder 1
2, cylinder 28, presser cylinder 36 and cylinder 44
B and the like are controlled by a control device (not shown). The displacement sensor 40 described above is connected to the control device. An encoder is connected to the rollers of the roller conveyor 33 so that the extrusion dimension of the strip 42 can be indirectly measured from the rotation speed of the rollers.

Next, the operation of the present embodiment will be described. For example, in the case of manufacturing strips with thinned ends,
As shown in FIG. 5, first, the lower cap plate 20B is moved upward to approach the upper cap plate 20A, the gap between the lower cap plate 20B and the upper cap plate 20A is narrowed to a predetermined dimension, and the extruder 12 is driven. The strip 42 is extruded by at least the joint length.

Then, as shown in FIG. 6, the cylinder 28
Is operated to slide the lower mouthpiece plate 20B downward, widen the interval between the lower mouthpiece plate 20B and the upper mouthpiece plate 20A to a predetermined dimension, and extrude a predetermined amount of the strip 42.

After that, as shown in FIG. 6, the gap between the lower mouth plate 20B and the upper mouth plate 20A is narrowed again to a predetermined size and at least the joint length band 42 is extruded, and the cutter of the fixed length cutting machine 44 is cut. 44A is lowered and the rear end of the strip 42 is cut.

When the strip 42 is extruded, the pressing cylinder 36 is activated and the slide block 2
4 is pressed against the main body block 22. Thereby, the lower cap plate 20B is brought into close contact with the slide member 34, and the rubber is prevented from leaking between the lower cap plate 20B and the slide member 34.

The strip 42 extruded in this way
Since both ends are thin-walled, as shown in FIG. 7, by stacking thin-walled portions and jointing them, a ring-shaped object having a uniform thickness can be formed.

Further, in the variable gauge 10 for extruding strips of this embodiment, the thickness of both ends of the strip 42 can be automatically reduced, so that a plurality of strips can be stacked or added together. Compared to the method, it is less laborious and production efficiency is high.

Although the lower base plate 20B is movable in this embodiment, the upper base plate 20 is not movable.
A may be movable, and the lower cap plate 20B
Both the upper base plate 20A and the upper base plate 20A may be movable.

The material of the band-shaped material may be plastic other than rubber, resin such as vinyl, clay, and the like.

When a rubber crawler is manufactured with a belt having a constant thickness, a damage of about 2% of the total weight is caused at the time of circle vulcanization. Make a ring of a certain thickness with the used band,
Thus, when the rubber crawler is manufactured, the damage during vulcanization can be reduced to about 0.5%.

Conventionally, a large amount of raw rubber was required in anticipation of rubber leakage from the mold, but an annular material having a constant thickness can be formed, and leakage during vulcanization can be reduced. Therefore, the amount of raw rubber used can be suppressed.

[0038]

EFFECT OF THE INVENTION Since the variable gauge head for extruding strips according to claim 1 has the above-mentioned structure, it has an excellent effect that a strip having a partially changed wall thickness can be efficiently manufactured.

Further, in the variable gauge for extruding strips according to the second aspect, in the variable head for extruding strips according to the second aspect, the die member can be easily moved, and automation is possible. It will be possible.

[Brief description of drawings]

FIG. 1 is a side view in which a part of a gauge variable head for extruding a band-shaped material according to an embodiment of the present invention is shown in section.

FIG. 2 is an enlarged view of the vicinity of the base of FIG.

FIG. 3 is a front view of the gauge variable head for extruding the strip shown in FIG.

FIG. 4 is an enlarged view of the vicinity of the mouthpiece showing an initial state of extruding the band-shaped material.

FIG. 5 is an enlarged view of the vicinity of the mouthpiece showing a state in the middle stage of extruding the band-shaped material.

FIG. 6 is an enlarged view of the vicinity of the mouthpiece showing a state at the final stage of extrusion of the band-shaped material.

FIG. 7 is a side view of an annular body made of a band.

FIG. 8 is a side view of a ring-shaped object formed of a band-shaped object having a constant thickness.

FIG. 9 is a schematic configuration diagram of a vulcanizer that performs circle heating.

FIG. 10 is a perspective view of a strip having a thinned end portion formed by a conventional method.

FIG. 11 is a perspective view of a band-shaped object having a thinned end portion formed by another conventional method.

[Explanation of symbols]

 10 Strip Variable Extrusion Gauge Head 12 Extruder 20A Upper Base Plate (Base Member) 20B Lower Base Plate (Base Member) 28 Cylinder (Drive Means) 42 Band

Claims (2)

[Claims] 1. A gauge variable head for strip-shaped material extrusion for determining an extrusion shape of a strip-shaped material extruded by an extruder, comprising a pair of opposed die members, at least one of the pair of die members facing each other. The strip-shaped article extruding gauge variable head, which is provided so as to be movable in a direction in which the strip-shaped article is moved toward and away from the die, and pushes out the strip from between the pair of die members. 2. The gauge variable head for extruding a belt-like article according to claim 1, further comprising a drive means for moving the mouthpiece member.