JPS6097824A - Die for extruder - Google Patents

Abstract

PURPOSE:To enable to keep on extruding molding material under steady operating conditions even just after the replacement of a mouthpiece by a method wherein the molding material is kept on being extruded through a bypass by changing-over a shutter when the replacement of the mouthpiece is intended. CONSTITUTION:When the replacement of a mouthpiece 15 followed by the change of tire size is intended, at first, the piston rods 27 and 28 of cylinders 25 and 26 (not shown in fig.) are synchronously put into actuation so as to shift a shutter 23 in the direction towards the other end so that the other side end of a first slider 21 is located nearly on the one side surface 13 of a bypass projection 12 and stop the shutter 23. As a result, a bypass recess 14 communicates to an opening 24, while a molding recess 17 is blocked by the first slider 21. Secondly, the mouthpiece 15 is shifted in the direction indicated with the arrow (c) so as to draw out of a holder 8 in order to replace with other mouthpiece. Even during the above-mentioned replacement work, rubber is continuously extruded through the bypass. After the replacement of mouthpiece, the shutter 23 is reset to its initial location by actuating the cylinders 25 and 26 (not shown in fig.) synchronously. Consequently, the rubber is extruded through the molding recess 17 again. Thus, when molding operation is restarted, the shifting to steady operating conditions can be quickly realized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a die for an extruder that is provided in the head of an extruder and defines the cross-sectional shape of a molded material to be extruded.

Conventionally, the cross-sectional shape of the molded material extruded from an extruder, such as tread rubber, changes depending on the type of tire, but this cross-sectional shape is changed by replacing the die mouthpiece of the extruder. . In order to replace this cap in a short time, various methods have been proposed in the past, such as one described in Japanese Utility Model Application Publication No. 56-139527. However, in all of these devices, when replacing the die, the operation of the heating roll and extruder must be stopped. For this reason, when the operation is restarted, the operating conditions such as the temperature, hardness, and extrusion speed of the rubber in the extruder become unstable, and as a result, the molded material extruded during the period until the operating conditions stabilize to steady values There are problems with quality such as dimensional accuracy, and there are cases where the product has no choice but to be discarded.

This invention was made in view of the above-mentioned problems, and an object of the invention is to provide a goo for an extruder that can continuously extrude a molded material regardless of whether the nozzle is replaced.

Such a purpose consists of: - a fixing block having a bypass recess formed on one side, an exchangeable base having a molding recess formed on the other side opposite to the bypass recess and having the same cross-sectional shape as the molding material; A shutter is provided on the upstream side of the block and the base and is movable perpendicularly to one side of the fixed block and has an opening through which the molding material passes.When extruding the molding material, the shutter is moved. Position the other end of the opening almost on the other side of the base, and
When extruding the molding material through the molding recess and replacing the die, move the shutter so that one end of the opening is approximately on one side of the fixed block, and push the molding material through the opening and the bypass recess. This can be achieved by doing more.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In FIG. 1.2, (1) is an opposed type extruder, and a molded material such as tread rubber (2) is extruded from this extruder (1). The extruder (1) has a head (3) in the center, and a die (4) below the head (3) that defines the cross-sectional shape of the tread rubber (2).
is attached, and the tread rubber (2) extruded through this die (4) is conveyed to the next process by a conveyor (5). The extruder (1) has a tread rubber (2
) to the die (4) for sending the rubber forming the widthwise end portions of the tread rubber (6), and 8 paths for sending the B type rubber forming the widthwise central portion of the tread rubber (2) to the die (4). (7)
・A, B kneaded by a heating roll (not shown) are formed in these A, 8 passages (6) and (7).
Seed rubber is supplied respectively. The die (4) extends in the front-rear direction, and has a substantially prismatic holder (
8). A horizontal rectangular hole (9) is formed in the center of this holder (8), and this rectangular hole (
A penetrating rectangular discharge hole (10) is formed between the holder (8) and the lower surface of the holder (8). This discharge hole (1o)
A step (11) is formed at the upper part of the inner surface on the negative side, and a bypass protrusion 02) as a fixed block that projects toward the step 01) is formed at the upper part of the other side inner surface.

As shown in FIG. 4, a bypass recess 04), which has almost the same cross-sectional shape as the maximum width of the tread rubber, is formed on the side surface (13), that is, the tip end surface, of this bypass protrusion (12). (14) penetrates in the vertical direction and extends in the longitudinal direction of the die (4). The step (1
1), a flat plate-shaped cap (15) parallel to the die (4) is supported so as to be slidable in the longitudinal direction shown by the arrow (C), and this cap (+5) is slid in the longitudinal direction to attach to the holder ( 8) It can be replaced with a different type of cap by pulling it out. A molding recess (17) having the same cross-sectional shape as the tread rubber (2) to be extruded is formed on the other side surface (16) of the base (15) opposite to the bypass recess (14), and this molding recess 0'7 ) penetrates in the vertical direction and the die (4)
extends in the longitudinal direction. Further, the other side surface (16) of the cap (15) comes into contact with the negative side surface (13) of the bypass protrusion (12), and as a result, the bypass recess (14) and the molding recess (1
71 and communicate with each other at the open end. Again, in FIG. 1, a support frame (18) is attached to the front surface of the head (3), and a die (4) is attached to this support frame (18).
) is attached to the cylinder (19) located on the extension line of the cylinder (19). This cylinder 09) piston rod (20
) to which the front end of the base (15) is detachably connected. Again, in Figure 3.4, the rectangular hole (
9), a pair of first and second sliders (21+1221) parallel to the die (4) are slidably housed in the die (4), and these first and second sliders (21+(221) as a whole have a bypass protrusion ( 121 and a shutter f231 provided on the upstream side of the base (15).In other words, the shutter (23) includes the first and second sliders (2+1
(A rectangular opening (24) extending parallel to the die (4) is formed between 221, and this opening (24) penetrates in the vertical direction, allowing the rubber to pass through.
The width of 4) is larger than both the depth of the bypass recess (14) and the depth of the molded recess 07).

Again, in Fig. 1.2, (25+!26) are two pairs of cylinders attached to the head (3), and each cylinder (251f26i is a The cylinder (
251 (26+ piston rod (21F28+ tip has first and second slider (2) 1 (
22) at the negative end and the other end of 1. Each is connected. As a result, when cylinder f251 (26+) operates synchronously, the first and second sliders (211F22+,
In other words, the shutter (23) moves the inside of the base and the bypass protrusion (12) from the side (1) of the bypass protrusion (12).
3) move in unison perpendicular to. Again, the third
In the figure, (2 (g)) connects the -L surface of the holder (8) and the opening (24) of the shutter (23).
), and the central thrower (29+) has a central insert (30) located upstream of the shutter (23) as shown in FIG.
) is slidably housed. Furthermore, this figure 5 shows -
Because half of the insert is omitted, one center insert (3
0) Although not shown in the figure, the other central insert, which is paired with this central insert 1 (301) and is equidistant from the longitudinal center of the guide (4), is actually placed in the omitted upper half. (301 are spaced apart from each other, and as a result, there is a passage (31) between these central inserts) through which the Class B rubber passes. Again, in Fig. 1, the support frame (32) is also visible on the rear surface of the head (3), and the support frame (32) is parallel to the support frame (3) and the support frame (3) is parallel to the guide (4). cylinder (331 (
341 is attached. These cylinders (33
) (34), the tips of the piston rods (351 (361) are connected to the one and other central inserts (30) through connecting plates (30) as shown in FIG. By protruding or retracting the piston rod (35) (341) by an equal amount, both central inserts (301) approach and separate from each other by an equal amount, and the length of the passage ('3+1) changes.

Center thrower) + 29) has a center thrower) +29) on the - blade side.
An insert recess (38) parallel to the insert recess (29) is formed, and one end of the insert recess (38) is formed in the insert recess (38).
(39+ is slidably housed in the center insert) (Similar to 301, this insert recess (38)
houses the other end insert (not shown). Each end inserter) (3q) has an inclined recess (
40) is formed, and each inclined recess (4(1) is located on the outer side in the longitudinal direction from the tip surface of the central insert (30). Also, (41) is formed between the inclined recess (401 and the opening (2). It is a communication port that communicates with the leak, and the inclined recess (40
The A type rubber supplied to 1 is led to the opening (24) through the communication port (41), and is led to the opening 0 through the passage (31).
It merges with both ends of the B class rubber guided by 4i. again,
In Fig. 1, the support frame (18) (39Q has a cylinder (42) parallel to the cylinder (33+ +341).
) 1431 were investigated, and these cylinders (42
) (The tips of the piston rods (44) and (45) of 431 are connected to the one end inserter and the other end inserter) (respectively to 391 through the connecting plate) (46), and these end inserts (so-called the above-mentioned end inserts) Central insert (30)
The cylinder (42) (F43) moves by an amount equal to that of the cylinder (42) (F43). In Figure 3.6, (47) is the holder (8
) is a supply plate fixed to the upper surface of the supply plate), and the supply plate (47) has a penetrating end supply port (48) for supplying the Class A rubber in the entry passageway (6) to the inclined recess (40); 8 passages (a penetrating central supply port (49) for supplying type B rubber in the direction to the passage (31) is formed, and these ends and the central supply port (48) (4q) are end inserters) (
39), central insert) Even if (30) moves, A, B
The seed rubber is fed into the inclined recess (40) and the passageway (31), which extends in the longitudinal direction of the gouer (4).

Next, the operation of one embodiment of the present invention will be explained.

Now, the tread rubber (2) with a predetermined cross-sectional shape is put into the extruder (1).
). At this time, the opening of the shutter (23) (the other end 60 of 2(A)), that is, the negative end of the second slider (22),
As shown in the figure, it is located approximately on the other side surface (16) of the cap (15). For this reason, the molding recess (+7) is the opening (
24), but the bypass recess (14) is connected to the shutter +'l! 31, second slider (22),
is blocked by.

As a result, A and B paths f6) (7) from the heat input roll
The A and B type rubber supplied respectively to K are supplied through the end supply port (4
8), the inclined recess (40), the communication port (4υ), the central supply port (49), and the opening (2
4), where they merge and are then extruded through the molding recess 0'7). At this time, the cross-sectional shape of the tread rubber (2) is the other end 60) of the opening (24) and the molded recess (
17).

Next, with the change in tire size, tread rubber (2
), the cap (15) is changed. In this case, first, cylinder f251
The piston rods I271f28) (26) are actuated synchronously to move the shutter (23) in the lateral and end directions. This movement is caused by the - side end (
51), that is, the other end of the first slider (21), stops when it is approximately located on the negative side surface (13) of the bypass protrusion (12). As a result, the bypass recess (14) comes to communicate with the opening (24), and the molded recess 07)
is the shutter (23), that is, the first slider (21
), is occluded by. As a result, the A and B type rubbers in the opening (24) are pushed out through the bypass recess (14), and the molding recess 0'? ), the A and B rubbers will not come into contact with each other at all. At this time, tread rubber (2)
The cross-sectional shape of is defined by the negative end r51) of the opening (24) and the shape of the bypass recess (14). Next, the piston rod (20) of the cylinder (19) is retracted, the mouthpiece (15) is moved in the direction of the arrow (C), and the holder (8) is moved.
extract it from

Next, a cap with a molded recess corresponding to the size to be changed is inserted, and the cap is replaced. Even during this exchange process,
Since the tread rubber (2) is continuously extruded without stopping the operation of the heating roll and extruder (1), the operating conditions at this time, such as the temperature, hardness, extrusion speed, etc. of the rubber, are the same as those of steady operation. There is almost no difference between the operating conditions and the operating conditions are similar. At this time, if the amount of change in the width of the tread rubber (2) is within a predetermined range, the cylinder (33+ (34+
(42) G131 piston rod (3!'1) (3
The 6jf persimmons (45) are synchronously protruded or retracted by an equal amount. As a result, the pair of center and end inserters (30) (39+) are moved closer to each other and separated from each other centering on the longitudinal center of the die (4), and the boundary between the A and B type rubbers is well set. Like, shutter 123)
The inserts (30) (391) located further upstream are each divided into two parts in the longitudinal direction, and these parts are moved closer to each other and separated from each other, so that while continuously extruding the tread rubber (2), the boundary between the A and B type rubbers is When the cap is replaced in this way, the cylinder (251 (2)
6) are operated synchronously to return the shutter (23) to its initial position. As a result, the A and B type rubbers are again extruded through the molding concavities (■η, and the tread rubber (2) with the required cross-sectional shape can be obtained. At this time, as mentioned above, when replacing the base, the operating conditions are Since there is almost no change, the operating conditions shift to normal operating conditions immediately after resuming extrusion.As a result, there is no deterioration in quality such as dimensional accuracy after replacing the die.

As explained above, according to the present invention, the molding material can be continuously extruded regardless of whether the nozzle is replaced, and as a result, even immediately after the nozzle is replaced, the molding material can be extruded under steady operating conditions, and the quality of the molding material can be improved. improves.

[Brief explanation of drawings]

Fig. 1 is a plan view showing an embodiment of the present invention, Fig. 2 is a front view thereof, Fig. 3 is a sectional view of the die, Fig. 4 is a perspective view of the main parts near the base, and Fig. 5 is a 6th cross-sectional view taken along the line T-T in the figure.
The figure is a sectional view taken along the line ■-■ in FIG. 3, and the upper half of both FIGS. 5 and 6 is omitted. (1) Extruder (2) Processing material (tread rubber) (3) Spatula (4) Die (12)
...Fixed block (bypass protrusion) (13)...-
Side surface (141... Bypass recess (I5), base (1
6)...Other side (1η...molding dent (231...
・Shutter (24)...Opening 60)...Other side end (51)...-side end Patent applicant Brideston Tire Co., Ltd. Agent Patent attorney Ta 1) Toshio Figure 5 31 Figure 6

Claims (1)

[Claims] The die of the extruder is provided in the head of the extruder and defines the cross-sectional shape of the molded material to be extruded. It has a replaceable cap in which a molding recess with the same shape as the cross-sectional shape is formed, and an opening that is provided upstream of the fixed block and the cap and is movable perpendicularly to one side of the fixed block, through which the molding material passes. and a shutter, when extruding the molding material, move the shutter to position the other end of the opening approximately on the other side of the base, extruding the molding material through the opening and the molding recess,
When replacing the cap, the shutter is moved so that one end of the opening is positioned approximately on one side of the fixed block, and the molding material is extruded through the opening and the bypass recess. Machine die.