JP2003340903A - Apparatus and method for covering cord with rubber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and a method for continuously covering the surface of a cord used as a core wire of a transmission belt or the like with an unvulcanized rubber to dispense with the adhesive rubber of the transmission belt. <P>SOLUTION: The apparatus for covering the cord with the rubber is equipped with (1) an extruder 2 for kneading the unvulcanized rubber by the rotation of an extrusion screw to extrude the same; (2) a pair of dies 3a and 3b connected to the extruder 2 to form respective rubber passages, that is, a bypass passage 15, a main passage 16 and a discharge passage 17; (3) a cord running part 4 provided in a pair of the dies 3a and 3b to face to the main passage 16; (4) a guide member 5 arranged in the cord running part 4 of one die and passing the cord through a guide hole 21 to guide the same to the main passage 16; (5) a rubber covering mold 6 arranged in the cord running part 4 of the other die, and passing the cord to which the rubber adheres through the piercing passage 25 to apply and fix the rubber to the cord; and (6) a regulation member 7 capable of controlling the amount of the roller discharged from the discharge passage 17. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device and a method for coating a cord with rubber, and more specifically, it continuously coats an unvulcanized rubber on the surface of a cord used as a core wire of a power transmission belt or the like and transmits the power. The present invention relates to a device and method for coating a cord with rubber, which does not require adhesive rubber for a belt.

[0002]

2. Description of the Related Art Industrial belts for power transmission such as V-belts, V-ribbed belts and toothed belts are made of fiber material such as polyester fiber, aramid fiber or glass fiber as a tensile core wire. And the code is used. In order to improve the adhesion of this cord to rubber materials, RFL treatment alone or RFL treatment after pretreatment with an epoxy or isocyanate compound, or RFL treatment
After the L treatment, the rubber paste was attached.

Usually, the above cord is continuously pulled out from the creel while applying a certain tension by a driving roll in a cord dipping machine, impregnated with an adhesive liquid in a dip tank, and then sent into an oven to be dried by heating. After that, after being cooled outside the oven and finishing the first treatment step, the same treatment steps as the second, third and fourth treatments are repeatedly passed, and each treatment is impregnated with a treatment liquid having a different composition. Adhesion and heat drawing treatment under different oven temperature conditions and tension conditions were given to the belt to give optimum cord physical properties and wound on a reel to complete the dip treatment.

As another method, the treatment liquid is passed along a roll having a relatively large diameter, or the roll is wound so as to pass a core wire between two rolls arranged in a bath. Means such as passing through the liquid have been adopted.

Still another method is disclosed in Japanese Patent Laid-Open No. 8-
Japanese Patent No. 108496 describes that a steel cord unwound from a spool is passed through a rubber extruder to coat the entire surface of the steel cord with rubber in a concentric circle shape.

[0006]

However, in the case of the dip processing machine, since the processing liquid uses a solution containing rubber or resin as a base material, the contents thereof are solidified during long-time operation. was there. Due to the adhesion of solidified substances, the automatic on-off valve may be clogged, causing troubles such as malfunctions.Besides, since processing liquids containing organic solvents such as toluene, which are generally used as solvents, are used, fire and disaster prevention is required in these processes. In addition, it is necessary to use explosion-proof equipment at the parts where the level switch, automatic switching valve, etc. come into contact with the processing liquid. In addition, there are many drawbacks such as an increase in size due to heavy equipment of equipment, difficulty in maintenance work, and increase in equipment cost.

Further, when the cord is passed through the bath containing the rubber paste, it is difficult to attach a large amount of rubber to the cord because the viscosity of the rubber paste is set to be small. When a transmission belt was formed using the cord overcoated with, the adhesive rubber sheet was used to adhere to the rubber layer of the belt body.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and addresses the problem. The unvulcanized rubber is continuously coated on the surface of a cord used as a core wire of a transmission belt or the like to bond the transmission belt. It is an object of the present invention to provide an apparatus and method for coating a cord with rubber that does not require rubber.

[0009]

In order to achieve the above-mentioned object, the invention according to claim 1 of the present application is a device for continuously coating the surface of a cord with unvulcanized rubber, which is not vulcanized by the rotation of an extrusion screw. An extruder for kneading and extruding vulcanized rubber, a pair of dies connected to the extruder to form rubber passages of a bypass passage, a main passage, and a discharge passage, and a main passage in the pair of dies And a guide member that is arranged in the cord running portion of the one die to guide the cord to the main passage through the guide hole, and a cord running portion of the other die. An apparatus for coating a rubber with a rubber, which comprises a rubber coating die which is disposed and which is coated and fixed by passing a cord to which a rubber is attached through a through passage.

In this apparatus, the rubber extruded by the extruder is constantly made to flow through the rubber passages of the bypass passage, the main passage, and the discharge passage formed by the pair of dies, and the cord is run by the pair of dies. The rubber is attached by passing through the guide hole of the guide member installed in the section and crossing the main passage, and then continuously passing through the rubber covered type through passage to continuously coat and fix the cord surface. Moreover, the cross-sectional shape of the rubber covered with the rubber coating die is arbitrarily determined. When the adhesive rubber of the power transmission belt is used as the rubber and the core wire of the power transmission belt is used as the cord, the adhesive rubber becomes unnecessary when the power transmission belt is molded.

According to the second aspect of the present invention, there is provided an apparatus for coating a cord with rubber having an adjusting member capable of controlling the amount of rubber discharged from the discharge passage. It is possible to increase the amount of rubber attached to the cord by increasing the internal pressure of the cord. On the other hand, when the coating process is not performed, the discharge amount of the rubber is increased, and the rubber is mainly stored in the tank disposed outside the discharge passage via the bypass passage and reused without remaining.

The present invention as set forth in claim 3 is an apparatus for coating a cord with rubber having a rectangular cross section of a rubber-covered through passage, wherein the rubber coating the cord has a rectangular or square cross section. Thus, when used as the core wire of the transmission belt, the arrangement of the core wires during spinning becomes good.

The invention according to claim 4 of the present application resides in an apparatus for coating a cord with rubber provided with two guide holes provided in the guide member, and the processing ability for coating the rubber is further enhanced.

The invention according to claim 5 of the present application is an apparatus for coating the cord with the unvulcanized rubber extruded from the extruder, the rubber being always flowing through the bypass passage, the main passage and the discharge passage. Yes, it prevents rubber from remaining.

According to a sixth aspect of the present invention, in the method of continuously coating the surface of the cord with unvulcanized rubber, the rubber kneaded and extruded by an extrusion screw is used to form a bypass passage provided in the outer peripheral direction of the die and a straight line. -Like main passage and each rubber passage of the discharge passage are discharged without flowing, at the same time the cord is moved across the main passage, and the rubber is adhered in the main passage, and the adhered rubber has a predetermined cross section. This is a method of coating the cord with rubber that is fixed to the cord so as to have a shape.

That is, in the method of the present invention, the rubber extruded by the extruder is constantly made to flow in the respective rubber passages of the bypass passage, the straight main passage, and the discharge passage provided in the outer peripheral direction of the die, and By passing the above cord through the guide hole of the guide member installed in the traveling part of the pair of dies and traversing this passage, the rubber is attached, and then the cord is continuously passed through the through passage of the rubber coating type cord. The cross-sectional shape of the rubber to be covered and fixed on the surface without any problem and to be covered with the rubber coating die is arbitrarily determined. When the adhesive rubber of the power transmission belt is used as the rubber and the core wire of the power transmission belt is used as the cord, the adhesive rubber becomes unnecessary when the power transmission belt is molded.

According to the seventh aspect of the present invention, in the step of coating the cord with the rubber, the rubber for adjusting the discharge amount of the rubber is reduced so that the rubber is easily attached to the cord by increasing the internal pressure of the passage. There is a coating method, which increases the amount of rubber attached to the cord and also ensures the attachment.

According to the eighth aspect of the present invention, in the step of not covering the cord with the rubber, there is provided a method of covering the cord with rubber for adjusting the discharge amount of the rubber so that the rubber does not stay in each rubber passage.

The invention according to claim 9 of the present application is a method for coating a cord with rubber, which is an adhesive rubber used for a transmission belt.

The invention according to claim 10 of the present application is a method for coating the cord with a rubber which reuses the discharged rubber.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a sectional view of an apparatus for coating a cord with rubber according to the present invention, FIG. 2 is a sectional view of FIG. 1 seen from the direction AA, and FIG. 3 is a sectional view taken along the line BB of FIG. Sectional view seen from the direction,
FIG. 4 is a front view of the guide member, and FIG. 5 is a front view of the rubber coating type.

The device 1 of the present invention is a device for continuously coating the surface of the cord with unvulcanized rubber and has the following constitution. That is, the present apparatus 1 includes an extruder 2, a pair of dies 3a and 3b forming rubber passages of a bypass passage, a main passage, and a discharge passage, and a pair of dies so as to intersect the main passage. The cord running portion 4 provided, the guide member 5 that guides the cord to the main passage by passing it through the guide hole, the rubber-covered mold 6 that coats and adheres the cord attached with rubber through the through passage, and discharges from the discharge passage. An adjusting member 7 for controlling the amount of rubber is provided.

The extruder 2 accommodates an extrusion screw 11 in a cylinder 10, puts a rubber (rubber compound) 12 through a raw material charging port (not shown), and kneads and extrudes by rotating the extrusion screw 11. . At this time, cylinder 1
Gas and the like generated from the air and rubber inside 0 are exhausted from an exhaust port (not shown). Although the temperature of the cylinder 10 is changed depending on the rubber type, it is usually adjusted to 40 to 100 ° C., and the rubber is heated to a temperature at which it is easily mixed and is thermoplasticized, so that it can be easily extruded. Further, the kneading time in this case is adjusted so that the vulcanization of the rubber does not proceed.

The pair of dies 3a and 3b are fixed to the extruder 2 through a mounting member 14 so as to be united at the center.
Each of the rubber passages is formed to allow the kneaded rubber 12 to flow to the outer peripheral direction of the die, to a bypass passage 15, a straight main passage 16, and a discharge passage 17. That is, the rubber 12 is divided into the 180-degree clockwise route and the counterclockwise route of the hollow bypass passage 15 provided on the outer peripheral portion of the one die 3b, merges again, and is discharged from the discharge passage 17 to the outside. It is discharged from the discharge passage 17 to the outside via the linear main passage 16 passing through the center point of one die 3b. The bypass passage 15 is provided because it is necessary to constantly flow in the rubber passage so that a predetermined amount of the extruded rubber 12 does not stay and solidify in the die 3. On the other hand, the main passage 16 has a wide entrance to facilitate the insertion of rubber, and serves as a portion for coating the rubber 12 on the cord 19 that moves in a direction intersecting with the passage, as will be described later. It is always flowing. The mounting member 14 has a heating means capable of adjusting the temperature of the die 3 to 60 to 150 ° C.

The cord running unit 4 includes a pair of dies 3a and 3b.
It is a space portion provided inside so as to face the main passage 16, and the cord 12 is made to enter the main passage 16 while traveling and the rubber 12 is coated.

The guide member 5 is arranged in the cord running portion 4 of one die 3a, and guides the cord 19 through the guide hole 21 to the main passage 16. As shown in FIG. 4, the guide member 5 is provided with two guide holes 21 through which two cords 12 pass and a positioning pin 22 is provided on the inner wall of the cord running portion 4 in the center of a stepped disc. By fitting in the guide groove 23, the guide member 5 is set accurately. Of course, two or more guide holes 21 can be provided.

The rubber coating mold 6 is arranged in the cord running portion 4 of the other die 3b, and the cord 1 is inserted through the through passage 25.
9 is coated with rubber 12. That is, as shown in FIG.
The rubber covered mold 6 has a through passage 25 having an opening 26 having a large outlet area at the center of the disc body, and has a cylindrical pressing member 2
It is installed on the bottom surface of the die 3b by inserting 6. At that time, the rubber-coated mold 6 has a guide groove 28 in which the positioning pin 27 inserted into the rubber-coated mold 6 is provided on the inner wall of the cord running portion 4.
Accurately installed by fitting into.

When the guide member 5 and the rubber coating mold 6 are correctly installed, the cord 12 is guided from the guide hole 21 to the main passage 16,
The guide hole provided on the bottom surface of the die 3b, the through-passage 25, and the open portion 26 can be linearly run to the outside to reliably cover a predetermined amount of rubber.

The adjusting member 7 controls the amount of rubber discharged from the discharge passage 17, and a rotary pin 30 having a through hole 31 provided in a direction perpendicular to the shaft is inserted into the mounting member 14 as shown in FIG. When the through hole 31 is aligned with the discharge passage 17, the passage is fully opened and the amount of rubber discharged is maximized. When the rotating pin 30 is rotated, the valve formed by the through hole 31 and the discharge passage 17 becomes smaller. The mechanism is to reduce the amount of rubber discharged.

When the amount of rubber discharged is reduced, the main passage 16
It is possible to increase the internal pressure of the rubber, ensure the adhesion of the rubber 12 to the cord 19, and increase the amount thereof. On the other hand, when the coating process is not performed, the passage is fully opened to increase the discharge amount of the rubber 12, and the tank disposed outside the discharge passage 17 mainly via the bypass passage 15 without leaving the rubber. It accommodates in 33. The rubber contained in the tank 33 can be reused.

However, in the method of continuously coating the surface of the cord 19 with the rubber 12, (1) as an initial setting, the cord 12 is inserted into the guide hole 21 and the main passage 16 is traversed to the bottom of the die 3b. The guide hole is provided, the through-passage 25, and the open portion 26 are pulled out so that the vehicle can run.

(2) Subsequently, the temperature of the die is changed to 60 to 120.
After the temperature is adjusted to 0 ° C., the rubber 12 extruded after kneading and extruding with the extrusion screw is provided on the outer peripheral portion of the die 3b.
5, the straight main passage 16 and the discharge passage 17 are discharged without flowing. The rubber 12 is diverted through the bypass passage 15 into a clockwise route and a counterclockwise route of 180 degrees, merges again, and is discharged from the discharge passage 17 to the outside, and at the same time, discharged from the discharge passage 17 to the outside via the main passage 16. It At this time, the valve of the discharge passage 17 is fully opened by the adjusting member 7 to increase the discharge amount of rubber.

(3) When the valve of the discharge passage 17 is slightly closed by the adjusting member 7 and the internal pressure of the main passage 16 is increased, rubber is attached while the cord 19 is running at 5 to 10 m / sec, and the rubber coating is performed. The rubber attached in the through passage 25 of the mold 6 is covered and fixed on the surface of the cord.

(4) 150 to 2 cords coated with rubber
It can be dried while running in a heating and drying oven whose temperature is adjusted to 20 ° C., and directly spun on the forming drum of the power transmission belt. In this case, if the adhesive rubber of the transmission belt is used as the rubber and the core of the transmission belt is used as the cord,
Adhesive rubber sheet is not required for the molding method.

(5) When the rubber coating is suspended,
The cord of the extruder is not pulled out, and the passage of the discharge passage 17 is fully opened until the rubber charged in the extruder is exhausted to increase the discharge amount of rubber and improve the rubber flow. The discharged rubber can be reused.

The rubber 12 used here is natural rubber, butyl rubber, styrene-butadiene rubber, chloroprene rubber, ethylene-propylene rubber, alkylated chlorosulfanated polyethylene, hydrogenated nitrile rubber, hydrogenated nitrile rubber and unsaturated carboxylic rubber. Mixed polymers with acid metal salts, ethylene-propylene rubber (EPR) and ethylene-
A rubber material such as an ethylene-α-olefin elastomer composed of a propylene-diene monomer (EPDM) alone;
Or mixtures of these are used. Examples of the diene monomer include dicyclopentadiene, methylene norbornene, ethylidene norbornene, 1,4-hexadiene, cyclooctadiene and the like.

A softening agent, a reinforcing agent made of carbon black, a filler, an antioxidant, a vulcanization accelerator, a vulcanizing agent and the like are added to the rubber.

As the above-mentioned softening agent, a general plasticizer for rubber, for example, phthalates such as dibutyl phthalate (DBP) and dioctyl phthalate (DOP), adipates such as dioctyl adipate (DOA), and dioctyl sebacate (DOS). ) And the like, phosphates such as tricresyl phosphate, etc., and general petroleum-based softeners. The rubber is preferably an adhesive rubber for a transmission belt.

As the cord 19 used here, a rope made of polyethylene terephthalate fiber, polyester fiber having ethylene-2,6-naphthalate as a main constituent unit, and polyamide fiber is used, and the purpose is to improve adhesion with rubber. Adhesive treatment is applied. As such an adhesion treatment, it is general that the fibers are immersed in resorcin-formalin-latex (RFL solution) and then dried by heating to form a uniform adhesive layer on the surface. However, the method is not limited to this, and there is also a method of performing pretreatment with an epoxy or isocyanate compound and then treating with an RFL solution.

[0040]

As described above, in the apparatus and method for coating the cord with the rubber of the invention according to the claims of the present application, the rubber extruded by the extruder is always formed with the bypass passage, the main passage, And let each rubber passage of the discharge passage flow,
Then, the above cord is passed through the guide hole of the guide member installed in the traveling portion of the pair of dies to traverse the main passage so that the rubber is adhered, and then the rubber-coated through-passage is continuously passed to continuously pass the rubber. Covered and fixed on the surface of the cord,
Further, the cross-sectional shape of the rubber covered with the rubber coating type is arbitrarily determined. When the adhesive rubber of the power transmission belt is used as the rubber and the core wire of the power transmission belt is used as the cord, the adhesive rubber becomes unnecessary when the power transmission belt is molded.

Also, by using an adjusting member capable of controlling the amount of rubber discharged from the discharge passage, the amount of rubber discharged is reduced to increase the internal pressure of the main passage and increase the amount of rubber attached to the cord. On the other hand, if the coating process is not performed, the amount of rubber discharged can be increased so that the rubber can be stored mainly in the bypass passage through the bypass passage and stored in the tank disposed outside without leaving the rubber. The rubber stored in can be reused.

[Brief description of drawings]

FIG. 1 is a sectional view of an apparatus for coating a cord with rubber according to the present invention.

FIG. 2 is a cross-sectional view of FIG. 1 viewed from the AA direction.

FIG. 3 is a cross-sectional view of FIG. 1 viewed from the BB direction.

FIG. 4 is a front view of a guide member.

FIG. 5 is a front view of a molding member.

[Explanation of symbols]

1 Device to coat rubber with cord 2 extruder 3,3a, 3b die 4 code running section 5 Guide member 6 rubber covered type 7 Adjustment member 11 Extrusion screw 12 rubber 15 Bypass passage 16 passages 17 discharge passage 19 codes

Claims (10)

[Claims] 1. An apparatus for continuously coating the surface of a cord with unvulcanized rubber, an extruder for kneading and extruding unvulcanized rubber by rotating an extrusion screw, and a bypass connected to the extruder. A pair of dies forming the rubber passages of the passage, the main passage, and the discharge passage; a cord running portion provided to face the main passage in the pair of dies; and a cord running portion of the one die. A guide member that guides the cord to the main passage through the guide hole, and a rubber-covered type that is disposed in the cord traveling portion of the other die and that coats the rubber-attached cord through the through passage to fix the cord. An apparatus for coating a cord with rubber, comprising: 2. An apparatus for coating a cord with rubber according to claim 1, further comprising an adjusting member capable of controlling the amount of rubber discharged from the discharge passage. 3. An apparatus for coating a cord with rubber as claimed in claim 1, wherein the rubber-coated through passage has a rectangular cross section. 4. An apparatus for coating a cord with rubber according to claim 1, wherein the guide member is provided with two guide holes. 5. The rubber according to claim 1, wherein the unvulcanized rubber extruded from the extruder always flows through the bypass passage, the main passage, and the discharge passage. Equipment for coating. 6. A method for continuously coating an unvulcanized rubber on the surface of a cord, wherein the rubber kneaded and extruded by an extrusion screw is used to pass a bypass passage provided in the outer peripheral direction of the die, a straight main passage, and a discharge. Each rubber passage is discharged without flowing, and at the same time, the cord is moved across the main passage, and the rubber is attached in the main passage, and the attached rubber is attached to the cord so that it has a predetermined cross-sectional shape. A method for coating a cord with rubber, which comprises fixing by coating. 7. In the step of coating the cord with rubber, the internal pressure of the passage is increased so that the rubber is easily attached to the cord.
The method for coating a cord with rubber according to claim 6, wherein the discharge amount of rubber is adjusted to be small. 8. The method of coating a cord with a rubber according to claim 6, wherein in the step of not coating the cord with the rubber, a large amount of rubber is adjusted so that the rubber does not stay in each rubber passage. 9. The method for coating a cord with rubber according to claim 6, wherein the rubber is an adhesive rubber used for a transmission belt. 10. The method according to claim 6, wherein the discharged rubber is reused.
9. A method for coating a cord with the rubber according to any of 8.