JPH09155885A - Method and apparatus for vulcanization of belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vulcanization apparatus which does not need a large initial equipment investment, is easy of step replacement and of automation in a method for vulanizing a rubber slab by a pair of heat boards the distance between which can be adjusted. SOLUTION: A cylindrical mold 1 in which an unvulcanized rubber slab 2 is engaged externally is held by a pair of parallel heat boards 3, 4, which are moved in the opposed directions to each other while being pressurized, the directions are inverted repeatedly at regular intervals, the heat boards 3, 4 are heated, and the rubber slab 2 is heated to be vulcanized. As a vulcanization apparatus, a heat board driving means (connection chain, movable motor, etc.) which makes the heat boards slide in opposed directions to each other is provided in addition to the mold 1 and the heat boards 3, 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for vulcanizing belts (transmission belts, conveyor belts, etc.). The power transmission belt is formed by kneading a predetermined rubber compound to form back rubber, adhesive rubber, bottom rubber, etc. into sheets, and sandwiching a tensile strength member (cord) on the outer peripheral surface of a cylindrical mold in a predetermined order. A cylindrical unvulcanized rubber sheet (also referred to as a slab including a vulcanized product) is molded by being wound around, and then vulcanized, sliced, and finished to be manufactured. The present invention relates to this vulcanization process.

[0002]

2. Description of the Related Art Conventionally, a vulcanization step in a method for manufacturing a transmission belt includes a method requiring a mold and a method not requiring a mold for each size of the transmission belt. As a method that requires a mold, there are a CM vulcanization method and a gasket vulcanization method, and an example of the gasket vulcanization method is shown in FIG. 3 (which is a sectional view). The mold 30 to which the unvulcanized slab 34 is fitted is erected vertically on the lower flange 32 of the gasket vulcanizing can 37, and the upper flange 31 is pressed against the upper part of the slab 34.
The steam inlet 3 is provided above and below the outer wall 36 and the mold 30, respectively.
5. After connecting the steam outlet 36, steam is introduced between the outer wall 36 and the sleeve 33 (made of rubber and expands and contracts) and into the mold 30 to heat and pressurize the slab 34 for vulcanization.

There are a press vulcanization method and a rotocur vulcanization method as vulcanization methods that do not require a die for each size.
As an example, the rotocure vulcanization method will be described with reference to FIG. A heating drum 40 which is heated to a predetermined temperature and is rotatable in the direction of arrow X, and a first tension roll 41 which can be moved toward and away from the heating drum 40 by a first hydraulic cylinder 47.
And the heating drum 40 by the second hydraulic cylinder 48 at a position symmetrical to the first tension roll 41 of the heating drum 40.
A second tension roll 45 that can be moved closer to and away from the heating drum 40, and a steel band 43 that is provided with guide rolls 44 and 49 above and below the heating drum 40 and laid between them. The second tension roll 45 is brought close to the heating drum 40, the guide rolls 44 and 49 are opened in the direction of the arrow Y, and at the same time, the first tension roll 41 is moved to the heating drum 40.
The unvulcanized belt 42 is hung between the two in the vicinity. Subsequently, a predetermined tension is applied to the first tension roll 41 in a direction in which the first tension roll 41 is separated from the heating drum 40, and the guide roll 44,
49 is closed and the second tension roll 45 is moved away from the heating drum 40 to move the steel band 4
3 is tensioned to press the belt 42. Heating drum 4
While rotating 0 while heating, the heater 46 can also heat from the back surface of the steel band 43. The vulcanization is completed by heating for a predetermined time.

In the press vulcanization method, although not shown, an unvulcanized belt is stretched between tension rolls usually provided in the vicinity of both ends of a plate-shaped heating plate with the heating plate sandwiched between the upper and lower parts. Vulcanization is performed by pressing and heating by an upper heating plate and a lower heating plate which are parallel to the heating plate.

[0005]

However, the above-described vulcanization device for a transmission belt has the following problems because it requires a vulcanization can for each size or the device becomes large. In the CM vulcanization method and gasket vulcanization method, it is necessary to prepare molds, sleeves, flanges, etc. depending on the size of the belt, which increases the initial capital investment and the number of man-hours required for setup change. Automation becomes difficult. Moreover, in the press vulcanization method, vulcanization of only the length of the hot platen is performed by one press, and the vulcanization near the edge of the hot platen (also referred to as burning boundary) becomes uneven, which tends to cause quality defects. . In the roto cure vulcanization method, since the belt is pressed by the steel band as described above, a large tension is required for the steel band, the apparatus becomes large and complicated, and it is not suitable for a small belt.

The present invention has been made in view of the above-mentioned points, and the initial facility investment is small and the setup change is easy.
An object of the present invention is to provide a belt vulcanizing method and a vulcanizing apparatus that are easy to automate.

[0007]

In order to achieve the above-mentioned object, the belt vulcanizing method of the present invention comprises: a) a pair of cylindrical dies that are rotatably supported and externally fitted to an unvulcanized rubber slab. While sandwiching and pressing by parallel heating plates, b) move each heating platen in mutually opposite directions and repeat inversion at a certain distance, and simultaneously heat those heating plates to remove the unvulcanized rubber slab. Heat and vulcanize.

The cylindrical mold for externally fitting the unvulcanized rubber slab is also used in the CM vulcanization method and the gasket vulcanization method.
As described above, the back rubber, the adhesive rubber, the cord, the bottom rubber and the like are sequentially wound and laminated on the cylindrical mold. Since the cylindrical mold is attached to a fixed position so that it can be raised and lowered and is freely rotatable, the cylindrical mold is sandwiched by parallel heating plates,
By sliding the hot plates in mutually opposite directions, the unvulcanized rubber slab fitted on the cylindrical mold is heated and vulcanized by the hot plate while being rotated. However, vulcanization of the slab is insufficient and non-uniform with one contact. Therefore, by reversing the movement of the hot platen at a constant distance and repeatedly heating, the entire surface of the unvulcanized rubber slab is uniformly heated and the whole is uniformly vulcanized. This fixed distance is a length with a half circumference of the unvulcanized rubber slab as a unit, and each part of the unvulcanized rubber slab is heated uniformly and does not cause a so-called burning boundary.

A vulcanizing apparatus according to claim 2 is: A) a lower hot platen slidably supported in a horizontal direction; and B) an axial center on the upper surface of the lower hot platen. A cylindrical mold that is rotatably mounted in a direction orthogonal to the moving direction of and has a rubber slab fitted on it, and C) is parallel to the lower heating plate and is slidable in the opposite direction, An upper heating plate that can be pressed into contact with and separated from the upper portion of the rubber slab that is externally fitted to the cylindrical mold by a pressing means, and D) a heating plate driving means that moves the upper heating plate and the lower heating plate in mutually opposite directions. It has and.

Since the lower hot platen is slidable in the horizontal direction, the cylindrical mold is rotatably held at a fixed position to heat the entire surface of the cylindrical mold, as will be described later. You can Since the lower heating platen is horizontal, it can be moved with the least driving force.

Since the axis of the cylindrical mold is oriented in a direction orthogonal to the moving direction of the lower heating plate, it can be freely rotated by the movement of the heating plate. The upper heating platen and the lower heating platen are slidable in mutually opposite directions, and heat and vulcanize the sandwiched unvulcanized rubber slabs while complementing each other. Since the unvulcanized cylindrical rubber sheet is repeatedly heated and pressed, the unvulcanized cylindrical rubber sheet is softened and slightly rolled at the same time as the vulcanization progresses, so that even if there is a nonuniform thickness portion, it tends to be uniform. In order to make the thickness more uniform, there is a method in which a liner is inserted between the upper hot plate and the lower hot plate and the shaft of the cylindrical mold and a strong pressure is applied while maintaining a constant interval. .

Since the upper heating plate can be moved up and down by the pressurizing means, the upper heating plate is raised when the setup is changed (the cylindrical mold having the rubber slab fitted is replaced). Make mold replacement easy. By lowering this, the rubber slab can be sandwiched and pressed between the upper side heating platen and the lower side heating platen.

The hot platen drive means repeatedly moves the upper hot platen and the lower hot platen in opposite directions to move a fixed distance, whereby the entire surface of the rubber slab is uniformly heated and vulcanized. . Specifically, the upper and lower heating plates are connected by a connecting chain to fix the mutual positional relationship, and the connecting chain is repeatedly driven to invert.

Grooves (concavities and convexities) forming a rib shape on the bottom rubber of the power transmission belt are provided on the surfaces of the lower heating plate and the upper heating plate of the vulcanizing apparatus, which are in contact with the rubber slab, and these are pressed against the unvulcanized rubber slab, By heating and vulcanizing while molding, a V-ribbed belt having a rib on the bottom rubber can be manufactured. In addition, in the method of manufacturing a V-ribbed belt, a rib is formed by cutting after vulcanizing a rubber slab having a flat bottom rubber surface.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a power belt vulcanizing method and apparatus according to the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing the entire apparatus according to this embodiment, and FIG. 2 is an upper heating plate 3 and a lower heating plate 4 of this embodiment.
3A and 3B are conceptual diagrams for explaining the operation with the cylindrical mold 1.

The vulcanizing apparatus shown in FIG. 1 has a lower heating platen 4 slidably supported in the horizontal direction, and an axial center (shaft 13) on the upper surface of the lower heating platen 4 which serves as the lower heating plate. A cylindrical mold 1 fitted with a rubber slab 2 rotatably mounted in a direction orthogonal to the moving direction (arrow Z) of the board 4, and a lower heat plate that is parallel to the lower heating plate 4. An upper hot platen 3 that can slide in the opposite direction to the platen 4, can be moved up and down by pressurizing means (hydraulic cylinder 9, upper rail 5), and can be pressed against the upper part of the rubber slab 2, and its upper hot platen 3 And the lower heating platen 4 are moved in opposite directions to each other, and a heating platen driving means (moving motor 11, connecting chain 8) is provided.

The lower heating plate 4 is slid in the direction of arrow Z on a lower rail 6 which is horizontally held by lower supporting plates 18 and 18 'supported by frames 10 and 10' which are erected on a base 12. It is movably attached. Since the lower rail 6 is attached horizontally, the lower heating platen 4 is kept horizontal and can easily slide. In this embodiment,
Although the lower support plates 18 and 18 'are fixed, by allowing them to be lifted and lowered by a lifting means such as a guide groove and a hydraulic cylinder, the work of attaching and detaching the cylindrical mold 1 can be further facilitated. The lower hot platen 4 and the lower rail 6 are not specified, but it is preferable that the lower hot platen 4 is provided with a groove and the lower rail 6 is engaged with the groove.

A cylindrical mold 1 fitted with a rubber slab 2 is attached with its axis centered in a direction orthogonal to the moving direction (arrow Z) of the lower heating plate 4, and its shaft 13 is attached to the lower heat plate. Board 4
Are attached to the slide bearings 14 provided on the upper portions of the columns 7 standing upright on both sides so as to be slidable only up and down. As a result, the cylindrical mold 1 fitted with the rubber slab 2 is pressed against the lower heating platen 4 by its own weight, and at a constant position even when the lower heating platen 4 moves in the direction of arrow Z. It is rotatably supported by. The upper part of the slide bearing 14 is opened, so that the cylindrical mold 1 can be easily attached and detached.

The upper hot platen 3 has a groove-like groove portion formed in the upper surface thereof in the direction of movement, and has a protrusion (the cross section has a wide bottom portion) corresponding to the groove portion and is horizontally arranged. It is slidably fitted on the supported upper rail 5. Both ends of the upper rail 5 are horizontally held by upper support plates 17 and 17 ', and the upper support plates 17 and 17' have upper and lower ends of the frames 10 and 10 'standing on the base 12, respectively. It is guided by the guide grooves 19 and 19 'provided in the above, and the central portions of the upper support plates 17 and 17' are supported by the hydraulic cylinders 9 and 9 'so as to be able to move up and down. When the cylindrical mold 1 is attached or detached, the upper heating platen 3 is raised to secure a desorption work space, and after the cylindrical mold 1 is mounted, the upper heating platen 3 is lowered to contact the rubber slab 2. It is contacted and heated and pressed to vulcanize it.

As the heating plate driving means, the ends of the upper heating plate 3 and the lower heating plate 4 are connected by connecting chains 8 and 8 '. Since the connecting chains 8 and 8 ′ have a predetermined length and are wound around the wheels 15 and 15 ′, the upper heating plate 3 and the lower heating plate 4 are moved in mutually opposite directions. The wheel 15 is driven by the moving motor 11 via the belt 16 and is inverted at a predetermined timing (time for sliding the hot plate a predetermined distance). The connecting chains 8 and 8'can be replaced by a toothed belt, which is advantageous in terms of noise and dirt. In order to move the upper heating platen 3 up and down, the connecting chains 8 and 8'are detachably attached to the heating plate.

By forming irregularities (grooves) corresponding to the rib shape of the bottom rubber of the V-ribbed belt on the surfaces of the upper heating plate 3 and the lower heating plate 4 that are in pressure contact with the rubber slab 2, the bottom rubber is simultaneously vulcanized. Ribs can be formed on the. In a V-ribbed belt having a plurality of ribs (protrusions) formed on the bottom rubber, a slab having a flat surface (bottom rubber) is usually vulcanized and then the ribs are formed on the bottom rubber portion by grinding. In the vulcanizing apparatus of the present invention, the upper slab 3 and the lower slab 4 are provided with grooves, which are pressed against the rubber slab 2 and heated to soften the rubber slab 2 to form ribs corresponding to the grooves. Then it is vulcanized. This makes it possible to manufacture a V-ribbed belt without providing a rib forming step after vulcanization.

As described in the above description of the vulcanizing apparatus, the method of vulcanizing the power transmission belt is as follows: a) A pair of cylindrical molds 1 on which the unvulcanized rubber slab 2 rotatably supported is fitted. While sandwiched by the parallel heating plates (upper heating plate 3 and lower heating plate 4) and pressurized by the pressing means (hydraulic cylinders 9 and 9 '), b) the respective heating plates 3 and 4 are opposite to each other. The unvulcanized rubber slab 2 is vulcanized by moving in the direction (arrow Z) and repeating the reversal at a constant distance, and simultaneously heating those heating plates 3 and 4. As shown in FIG. 2, this movement is brought into contact with the upper and lower parts of the cylindrical mold 1 fitted with the rubber slab 2 near the ends of the upper hot platen 3 and the lower hot platen 4, and presses them. The heating plates 3 and 4 are moved in the direction of arrow R while being heated (FIG. 2 (a)). The heating plates 3 and 4 move to the vicinity of the other end portion through the central portion (FIG. 2B) (FIG. 2).
(C)). At this position, the heating plates 3 and 4 are reversed and moved in the direction of arrow L. This operation is repeated to pressurize and heat the rubber slab 2 for vulcanization.

If the rubber slab 2 is thick, or if the upper heating platen 3 and the lower heating platen 4 alone do not provide sufficient heat, heating is performed by introducing steam into the cylindrical mold 1. Good.

[0025]

As is apparent from the above description,
The belt vulcanizing method and vulcanizing apparatus of the present invention have the following excellent effects.

1) In the conventional CM vulcanization method, gasket vulcanization method, etc., it was necessary to prepare a mold, a sleeve, etc. for each size of the transmission belt, but according to the vulcanization method of the present invention, a cylinder is used. Although a die is required for each size, a sleeve etc. is not required and initial capital investment is reduced. Also,
Since the process is simple, the man-hours for setup change are reduced, and automation is easy.

2) The press vulcanization system does not cause a so-called burning boundary, which is a quality defect, and the apparatus is smaller than that of the rotocur vulcanization system, which is particularly suitable for small-sized belts.

3) In the vulcanizing apparatus according to the third aspect, the ribs can be formed on the bottom rubber at the same time as the vulcanization, so that the step of forming the ribs after the conventional vulcanization can be omitted.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an entire belt vulcanizing apparatus according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram for explaining the operation of the upper heating plate 3, the lower heating plate 4 and the cylindrical mold 1 in the belt vulcanizing method of the present invention.

FIG. 3 is a sectional view showing an outline of a conventional gasket vulcanizing can.

FIG. 4 is a side view showing an outline of a conventional roto cure vulcanizer.

[Explanation of symbols]

 1: Cylindrical mold 2: Rubber slab 3: Upper heating plate 4: Lower heating plate 5: Upper rail 6: Lower rail 7: Struts 8: Connecting chain 9: Hydraulic cylinder 10: Frame 11: Moving motor 15: Wheel 17 : Upper support plate 18: Lower support plate

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masahiko Hozoji 3-15-15 Meiwa Dori, Hyogo-ku, Kobe, Hyogo Prefecture Bando Kagaku Co., Ltd.

Claims (3)

[Claims] 1. A cylindrical mold, which is rotatably supported and on which an unvulcanized rubber slab is fitted, is sandwiched by a pair of parallel heating plates, and the heating plates are moved in opposite directions while pressurizing. A method for vulcanizing a belt, characterized in that the unvulcanized rubber slab is vulcanized by simultaneously heating the heating plates and repeating the reversal at a certain distance. 2. A lower hot platen slidably supported in a horizontal direction, and an upper surface of the lower hot platen rotatable about an axis in a direction orthogonal to the moving direction of the lower hot platen. A cylindrical mold mounted on the outer periphery of the rubber slab, and a rubber slab that is parallel to the lower heating plate and slidable in the opposite direction, and is fitted onto the cylindrical mold by a pressing means. A vulcanizing apparatus for belts, comprising: an upper heating plate which is pressed against and separated from the upper part of the plate, and a heating plate driving means for moving the upper plate and the lower plate in mutually opposite directions. 3. The belt vulcanizing apparatus according to claim 2, wherein grooves corresponding to the shape of the bottom rubber of the transmission belt are formed on the surfaces of the lower heating plate and the upper heating plate that contact the rubber slab.