JP2003245935A - Apparatus for forming rubber sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide at a low cost an apparatus for forming a rubber sheet of simple equipment which forms a rubber sheet of a high precise shape and quality without generating rekneaded rubber. <P>SOLUTION: The apparatus for forming the rubber sheet is equipped with an extruder 11 for extruding a cast rubber material; a metering pump which meters and discharges a metered amount of the extruded rubber material; a nozzle 15 which forms the discharged rubber material of the regulated amount in a flat band state, a calender roll 16 which forms the flat band stated rubber material discharged from the nozzle 15 further into a specific flat band stated rubber sheet and sends it out; a width sensor 21 for detecting a width of the rubber sheet sent out from the calender roll 16; and a sheet width regulating means 20 which feed-back controls driving of the metering pump 12 based on the width of the rubber sheet detected by the width sensor 21 to send out the rubber sheet 1 of the specific width. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber sheet forming apparatus for forming a thin gauge sheet or the like as a constituent member of a tire.

[0002]

2. Description of the Related Art In the case of continuously forming a rubber sheet having a predetermined width with high accuracy, conventionally, as shown in FIG. 5, only a necessary shape portion 02 is cut out from a rubber sheet finally sent out from a calendar roll 01. The remaining portion 03 was used as a kneaded rubber to be kneaded back into an extruder or the like.

A change in the discharge amount of the rubber material to the calender roll affects the width of the molded rubber sheet and appears as a width variation, and in particular, both side edges of the molded rubber sheet have tapered portions that are tapered. If so, it is difficult to obtain a high width accuracy, and therefore, the rubber sheet sent by the calendar roll 01 is cut into a required shape,
The remaining return rubber 03 will be used for kneading.

As the taper portion of the rubber sheet has a smaller inclination angle (an acute angle) to improve the quality, it is more difficult to improve the width accuracy, and it becomes more and more necessary to cut it into a desired shape.

[0005]

[Problems to be Solved by the Invention] However, calendar rolls
Cutting the rubber sheet into the required shape with 01 requires a kneading function for kneading the remaining part 03, which is disadvantageous in terms of space and may easily cause troubles, possibly impairing productivity. .

Further, repeating kneading also changes the rubber characteristics, and in order to stabilize the quality, it is an operation that is not desired to be performed.

There is also a method of molding a rubber sheet with a high width accuracy by using a 1-roller die 05 as shown in FIG.
The roller die 05 is heavy and costly, and a small amount of rubber leaks, which requires regular processing.

The present invention has been made in view of the above problems, and an object thereof is to form a rubber sheet with a simple facility for forming a rubber sheet having high shape accuracy and quality without producing kneaded rubber. The point is to provide the device at low cost.

[0009]

In order to achieve the above object, the present invention according to claim 1 is an extruder for extruding a charged rubber material, and a constant amount of the extruded rubber material is discharged. A fixed amount discharge pump, a die for forming a fixed amount of the discharged rubber material in a flat band shape, a calendar roll for discharging the flat band-shaped rubber material discharged from the base into a predetermined flat band-shaped rubber sheet, and the calendar. A width sensor for detecting the width of the rubber sheet sent out from the roll, and a sheet width control means for feeding back the rubber sheet of a predetermined width by feedback controlling the drive of the constant quantity discharge pump based on the width of the rubber sheet detected by the width sensor. And a rubber sheet forming apparatus provided with.

Since the width of the rubber sheet delivered from the calender roll is affected by the amount of the rubber material discharged from the constant quantity discharge pump, the sheet width control means determines the width of the rubber sheet based on the width of the rubber sheet detected by the width sensor. By feedback-controlling the drive of the rubber sheet, it is possible to accurately and stably form and send out a rubber sheet of a predetermined width without producing kneaded rubber.

Since it is only necessary to provide a control system for the sheet width control means and the width sensor, the space is hardly expanded, and the conventional kneading function is not required, which is advantageous in terms of space as a simple and inexpensive facility. There are few troubles and very little hinders productivity. Since no kneading is performed, high quality can be maintained without changing rubber characteristics.

According to a second aspect of the present invention, in the rubber sheet molding apparatus according to the first aspect, a pressure sensor for detecting the pressure of the rubber material at the inlet of the metering discharge pump and the pressure of the rubber material detected by the pressure sensor. Pressure control means for feedback-controlling the drive of the extruder based on the above and maintaining the pressure of the rubber material appropriately.

The pressure control means feedback-controls the extruder to maintain the pressure of the rubber material extruded from the extruder and reaching the inlet of the constant amount discharge pump within a certain range, so that the discharge amount from the constant amount discharge pump is also increased. It is possible to easily maintain the shape of the rubber sheet fed from the calendar roll properly.

According to a third aspect of the present invention, in the rubber sheet forming apparatus according to the first or second aspect, a rectifying tube is interposed between the constant amount discharge pump and the mouthpiece, and the rubber material is a flat strip. It is characterized in that the rubber material is evenly supplied to the die to be formed.

When the distance from the constant quantity discharge pump to the head is short, the filling degree of the rubber in the head varies. Therefore, a rectifying tube is provided between the constant quantity discharge pump and the mouthpiece to prevent the rubber material from flowing into the head. It is possible to eliminate the bias of filling and keep it properly and stabilize it.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is an external perspective view of the rubber sheet molding apparatus 10 according to the present embodiment, and FIG. 2 is a side view thereof. The rubber sheet forming apparatus 10 continuously forms a smooth sheet 1 for forming a thin gauge sheet of a tire constituent member.

The smooth sheet 1 is formed in a flat band shape and has tapered portions 1a, 1a whose both end edges are tapered, and the smooth sheet 1 is mutually tapered.
A thin gauge sheet is formed while sequentially stacking a.

The rubber sheet molding apparatus 10 is shown in FIGS.
As shown in FIG. 1, the extruder 11, the gear pump 12, the straightening pipe 13, the cap 15 of the head 14 and the calendar roll 16 are arranged in this order, and the rubber material charged into the extruder 11 is molded to form a smooth sheet. It is continuously discharged as 1.

The extruder 11 extrudes into the gear pump 12 while kneading the charged rubber material and the like by rotating a screw. The gear pump 12 is a constant-quantity discharge pump that controls the rubber material extruded by the extruder 11 to a constant discharge amount based on the rotation speed of the gear and discharges it to the rectifying pipe 13.

The rectifying pipe 13 is a distance extension pipe for connecting the gear pump 12 and the mouthpiece 15 of the head 14 so as to provide an appropriate distance between them, and is interposed if necessary.

The discharge of the rubber material from the gear pump 12 is often concentrated. Therefore, when the distance from the gear pump 12 to the head 14 is short, the filling degree of the rubber in the head 14 varies, so that the gear pump 12 and the cap 15 Rectifier between
It is possible to prevent the bias of the filling of the rubber material into the head 14 by interposing 13 and properly maintain and stabilize the rubber material.

The mouthpiece 15 of the head 14 has a mouthpiece shape substantially close to the target cross-sectional shape of the smooth sheet 1 to be formed.

The target sectional shape of the smooth sheet 1 is shown in FIG.
As shown in (3), it has a flattened plate-like shape and has tapered portions 1a, 1a whose both edges are tapered. On the other hand, the mouthpiece of the mouthpiece 15 has the same shape as shown in FIG. It has a shape having a taper portion at the edge so that the appearance becomes closer to the target cross-sectional shape. However, the tip of the tapered portion is missing in the die shape.

By making the die shape of the die 15 follow the target cross-sectional shape, lateral flow of rubber can be prevented and a stable smooth sheet 1 can be obtained. Further, when a smooth sheet having tapered portions on both edges is formed, the shape of the die of the die 15 also has tapered portions on both ends, whereby the rubber volume can be adjusted to form a more stable smooth sheet 1.

The rubber material formed in the die shape of the die 15 is discharged between the upper and lower two rolls of the calendar roll 16. The calender rolls 16 sandwich the rubber material discharged from the die 15 by upper and lower rolls having a predetermined outer peripheral surface shape, mold the rubber material into a target cross-sectional shape, form the final smooth sheet 1, and continuously send it out.

In order for the smooth sheet 1 to form a target cross-sectional shape without producing kneaded rubber, the gear pump 12
Therefore, it is necessary to stably discharge and supply an appropriate amount necessary and sufficient for forming the target cross-sectional shape of the smooth sheet 1.

However, the discharge amount of the gear pump 12 slightly changes due to the temperature change and the minute variation of the rubber property, and this change has a great influence on the width of the smooth sheet 1. Therefore, the rubber sheet forming apparatus 10 is equipped with a sheet width control means 20 for feedback-controlling the width of the smooth sheet 1 discharged from the calendar roll 16.

That is, the width sensor 17 which is an optical sensor for optically detecting the width of the smooth sheet 1 is replaced by the calendar roll 16
(See FIG. 1) downstream of the gear pump, and as shown in FIG. 4, the seat width control means 20 determines the gear pump based on the detection width of the same width sensor 17.
12 is feedback-controlled.

At the same time, the present rubber sheet molding apparatus 10 has an extruder 11 for supplying a rubber material to a gear pump 12 as shown in FIG.
About the pressure control means 25 for controlling the supply pressure of the rubber material
Is equipped with.

Therefore, a pressure sensor is installed at the inlet of the gear pump 12.
26 is provided, and the pressure control means 25 feedback-controls the extruder 11 based on the pressure detected by the pressure sensor 26 so that the rubber material is always stably supplied at a pressure within a certain range.

In this way, the gear pump 12 to which the rubber material is supplied within a certain range of pressure is feedback-controlled by the sheet width control means 20, and the width of the smooth sheet 1 is monitored to appropriately control the rubber discharge amount in response to a minute change. By doing so, the width accuracy of the smooth sheet 1 can be maintained high.

As described above, the rubber sheet molding apparatus 10 is
Since the smooth sheet 1 having a highly accurate cross-sectional shape can be molded without producing kneaded rubber, the quality of the rubber does not deteriorate due to repeated kneading, and the kneading function is unnecessary, so that it is simple and inexpensive. It is advantageous in terms of space as a facility, has few troubles, and does not hinder productivity.

[Brief description of drawings]

FIG. 1 is an external perspective view of a rubber sheet molding apparatus according to an embodiment of the present invention.

FIG. 2 is a side view of the rubber sheet molding apparatus.

FIG. 3 is a diagram showing a target cross-sectional shape and a mouthpiece shape of a smooth sheet.

FIG. 4 is a block diagram of a control system of the rubber sheet molding apparatus.

FIG. 5 is a view showing a conventional calendar roll with kneading.

FIG. 6 is a view showing a conventional one-roller die.

[Explanation of symbols]

1 ... Smooth sheet, 10 ... Rubber sheet forming device, 11 ... Extruder, 12 ... Gear pump, 13 ... Rectifier tube, 14 ... Head, 15 ...
Clasp, 16 ... Calendar roll, 20 ... Sheet width control means, 21
... width sensor, 25 ... pressure control means, 26 ... pressure sensor.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) // B29K 21:00 B29K 21:00 F term (reference) 4F204 AA45 AG01 AP03 AQ01 AR03 FA06 FB02 FF01 FF23 FF46 FN08 FQ40 4F207 AA45 AG01 AP02 AR02 KA01 KA17 KL67 KL84 KL94 KM06 KM15 KW41

Claims (3)

[Claims] 1. An extruder for extruding a charged rubber material, a constant-quantity discharge pump for quantitatively discharging the extruded rubber material, a mouthpiece for forming the flattened shape of the quantitatively discharged rubber material, and a discharge from the mouthpiece. A calender roll which further forms a flat strip rubber material into a predetermined flat strip rubber sheet and sends it out, a width sensor for detecting the width of the rubber sheet sent out from the calender roll, and a rubber sheet detected by the width sensor. And a sheet width control means for feeding back a rubber sheet having a predetermined width by feedback-controlling the drive of the constant quantity discharge pump based on the width of the rubber sheet forming apparatus. 2. A pressure sensor for detecting the pressure of the rubber material at the inlet of the metering discharge pump, and feedback control of the drive of the extruder based on the pressure of the rubber material detected by the pressure sensor to control the pressure of the rubber material. The rubber sheet molding apparatus according to claim 1, further comprising: a pressure control unit that maintains the pressure appropriately. 3. A rubber material is supplied between the metering discharge pump and the cap so that the rubber material is evenly supplied to the cap which forms the rubber material in a flat band shape. The rubber sheet molding apparatus according to claim 2.