JPS6336936B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing power transmission belts such as flat belts, poly V belts, and low edge V belts. A cutting edge receiving sheet is interposed between the cylindrical drum and the laminated belt molded body, and a series of belt manufacturing processes such as molding, vulcanization, polishing, and cutting are performed continuously on a single drum, significantly reducing the number of man-hours. The purpose of this invention is to reduce the amount of heat generated and to obtain a transmission belt of good quality.

Conventionally, the production of poly V belts involves forming a belt laminate on a cylindrical iron drum, vulcanizing the belt molding, cooling the molding, removing the vulcanized sleeve-shaped belt molding from the drum, and removing it. Storage of the belt moldings, transfer of the belt moldings to an expander drum whose outer periphery is covered with vulcanized rubber, pre-cutting into a wide width, wrapping the pre-cut intermediate product between two pulleys on the sanding machine, and cutting the surface. The process involves cutting and polishing the sleeve into a V shape, attaching the sleeve with ribs to a cutting machine, and cutting the sleeve into small widths with a predetermined number of ribs.

In the above poly V belt manufacturing method, preliminary cutting,
Since we use a rib cut and two cutting processes, the belt side part is cut into a small width during the preliminary cut and discarded, resulting in a lot of scrap.
In addition, storage space is required to cool the sleeve-shaped belt molded product after vulcanization and removal.Furthermore, when polyester fibers with large heat shrinkage are used for the tensile material, heat generation during polishing ( 150°～
200℃) causes the belt to shrink, so it is necessary to apply a tensile force of about 1/10 of the belt tension while polishing the belt wound between a pair of pulleys. There were many problems, such as not being able to make the film (300mm).

On the other hand, in the production of a low edge type V-belt, forming a belt laminate on a cylindrical iron drum, vulcanizing the belt formed body,
Cooling of the molded body, Removal of the vulcanized sleeve-shaped belt molded body from the drum, Storage of the removed belt molded body, Transfer of the belt molded body to the expander drum, and subsequent V-setting of the individual V-belts. Shape cutting work, sanding work to polish the sides of the V-belt by wrapping the V-belt around a pair of pulleys to reduce vibration of the V-belt, inspection, finishing work such as deburring the belt, etc. However, in this manufacturing method, the wide vulcanized belt is transferred to another expander drum and this drum is expanded, making it difficult to form a perfect circle and causing variations in belt width when V-shaped cuts are made. , extra steps such as sanding work to polish the side surface of the V-belt are required, resulting in a large number of scraps and a complicated process.

In order to solve these operational problems, it would be desirable to be able to perform forming, vulcanizing, polishing, and cutting in a single drum in succession, from the standpoint of improving work efficiency and quality. If the belt molded body is directly wrapped around the cylindrical drum, there is a high risk that the cutting blade of the cutter will come into contact with the drum during cutting, damaging the blade and rendering it unusable.
The cutting blade also damages the drum surface, leaving uneven scars on the surface of the next belt molded product (the part that contacts the drum), and the molding, vulcanizing, polishing, and cutting operations are repeated on a single drum. There were many technical problems.

This invention was arrived at as a result of various studies aimed at solving the above-mentioned conventional problems.This invention is based on the invention, in which a cutting edge receiver is provided on the outer peripheral surface of the cylindrical drum in contact with the laminated molded body of the belt. A series of operations such as vulcanization, polishing, and cutting after forming the belt are carried out on a single drum with the sheets interposed and wound, and the damaged cutting edge receiving sheet is replaced after each belt manufacturing process is completed. Next, specific embodiments of the present invention will be explained using poly V belts and low edge V belts as power transmission belts.

First, in manufacturing the poly V belt shown in Fig. 3, reference numeral 1 in the figure is an iron cylindrical drum, and the entire outer periphery of the drum is covered with a smooth cutting blade receiving sheet 2 made of thick paper, cloth, resin sheet, etc. is wrapped (Fig. 1).

Next, on the outer circumferential surface of the cutting edge receiving sheet 2, a wide-angle canvas 5 with rubber, which is made of cotton yarn or a blended yarn of cotton yarn and synthetic fiber, and whose intersection angle of the warp and warp yarns is 85° to 145°, is placed on the outer peripheral surface of the cutting edge receiving sheet 2.
The belt is wound in one to a plurality of layers, usually one to two plies, in an endless form, with the wide-angle intersection portions aligned with the longitudinal direction of the belt. On top of that, NR (natural rubber), SBR (styrene-butadiene rubber), CR (chloroprene rubber),
A thin unvulcanized upper adhesive rubber sheet 6 made of a single material such as IIR (butyl rubber) or BR (butadiene rubber) or an appropriate blend of these is wrapped, and then an isocyanate-based or RFL (resorcinol formalin latex) is applied. A low-elongation, high-strength tensile rope 7 made of surface-treated and hot-stretched polyester fiber, nylon Kepler, or glass fiber is spirally wound under a constant tension, and then the upper part is bonded. An unvulcanized lower adhesive rubber sheet 8 made of the same material as the rubber sheet 6 is wrapped around it.

Next, an unvulcanized compressed rubber sheet 9 made of the same material as the adhesive rubber sheets 6 and 8 and having a certain thickness is wrapped around the belt to form a laminated body 20a of the belt. In addition, various short fiber groups may be embedded in this folded and compressed rubber sheet 9 in the same orientation in the belt width direction.

Next, the unvulcanized belt molded body is transferred to a vulcanization step together with the cylindrical drum and is vulcanized.

The vulcanized sleeve-shaped vulcanized belt molded body is
The grinder 12 is attached to a grinding machine (not shown) with the drum as it is without being removed from the drum 1, and has a plurality of band-like protrusions 11 at a predetermined pitch in the circumferential direction shown in FIG. 2 on the outer circumferential surface. While rotating the drum 1 holding the belt molded body on its surface in different directions, the protrusion 11 of the grinder 12 is gradually pressed firmly against the surface of the compressed rubber layer 9 of the sleeve-shaped vulcanized belt molded body, and the compressed rubber layer 9 gradually becomes a base. The product is cut and polished into a shape to form a ribbed sulfur belt molded body 20b having valleys 10 as shown in FIG. Grinder 12 used here
It is possible to obtain a rib-added sulfur belt molded product in which triangular protrusions are continuously provided on the lower surface of the belt by using a grinder in which triangular protrusions are adjacent to each other instead of the triangular protrusions having the spacing shown in the figure. can.

The rib-added sulfur belt molded body 20b thus formed is then cut by a cutting machine (not shown) together with the drum 1.
The belt is cut to a predetermined width until it reaches the cutting edge receiving sheet 2, and the belt is cut with a cutter (not shown) at the valley of the rib portion as shown by the dotted line, and then removed from the drum 1. , by reversing it, the tensile members 7 are buried in parallel in the adhesive rubbers 6 and 8 shown in FIG. A plurality of poly V-belts 21 are obtained to which the rubber-covered canvas 5 having a surface is attached. The cut blade receiving sheet 2 used here is removed from the drum 1 after completing one cycle of forming, vulcanizing, polishing, and cutting, and is discarded, and a new cutting blade receiving sheet 2 is used for the next molding. It is wrapped around the entire outer circumference of drum 1 for the next forming, vulcanization,
Polishing and cutting are repeated.

In this way, the blade receiving sheet 2 is
By repeatedly performing molding, vulcanization, polishing, and cutting by changing the drum, a series of manufacturing steps can be performed continuously on a single drum 1, reducing the number of man-hours and obtaining a poly V belt of good quality. Can be done.

Next, in manufacturing the low edge V-belt shown in Fig. 6, 1 in Fig. 4 is an iron cylindrical drum, and the entire outer periphery of the drum 1 has a wall thickness similar to that described in the poly V-belt manufacturing process. A cutting edge receiving sheet 2 made of paper, cloth, resin sheet, etc. is wrapped and covered.

The belt molded body is made of the same material as described in the production of the poly V belt, and is coated with a compressed rubber sheet 9 of a predetermined thickness on the outer peripheral surface of the cutting edge receiving sheet 2, followed by a lower unvulcanized adhesive rubber sheet 8, and a spiral. The tensile rope 7 is wound into a shape, and the upper unvulcanized adhesive rubber sheet 6 is wrapped thereon, and finally one to a plurality of wide-angle canvas layers 5 are sequentially wound in a laminated manner.

Unvulcanized belt molded body 20a thus molded
The whole cylindrical drum is transferred to the vulcanization process and cured.
After vulcanization, the sleeve-shaped vulcanized belt molded body 20b moves to the next cutting process together with the drum. Katsuto is
As shown in FIG. 5, first, one inclined round blade cutter 14 inclines in the direction of the arrow and cuts into the vulcanized belt formed body 20b, and then the other round blade cutter 15, inclined in the opposite direction, cuts in the same manner. A trapezoidal low edge V-belt 22 is manufactured by cutting down to the receiving sheet 2.

Next, by removing the cut belt from the drum, the tensile member 7 is embedded in the adhesive rubber 6, 8 as shown in FIG. 6, and has a compressed rubber layer 9b at the bottom.
In addition, a plurality of low edge V-belts 22 having the rubberized canvas 5 attached to the upper part are obtained.

Next, the cut blade receiving sheet 2 is removed and discarded from the drum 1 after one cycle is completed, and during the next molding, another sheet 2 is wrapped around the outer circumferential surface of the drum 1 to perform the next molding, vulcanization, and cutting. Do this repeatedly.

In the case of the first invention detailed above, in order to protect the cutting blade and the cylindrical drum, a sufficiently thick blade receiving sheet 2 is used, and care is taken to absorb errors in the depth of cut of the cutting blade. However, requiring a large wall thickness for the cutting edge receiving sheet 2 inevitably results in a large loss of material, which ultimately leads to an increase in the cost of the belt.

Here, the first invention is improved one step and during the manufacturing process of the target poly V belt and low edge V belt,
In particular, taking into consideration the characteristics of the cutting blade, a vulcanized rubber sheet is placed on the underside of the cutting blade receiving sheet without changing the basic position of wrapping the cutting blade receiving sheet on the cylindrical drum and at the position where it contacts the belt molded body. By interposing a vulcanized rubber sheet or a double rubber sheet made of an unvulcanized rubber sheet on its surface, the thickness of the cutting blade receiving sheet can be reduced and the cost of discarded materials can be reduced. In manufacturing a poly V belt 21 as the second invention, a specific embodiment thereof will be described with reference to FIGS. 7 and 8.

In the figure, 1 is a cylindrical iron drum, the entire outer periphery of which is covered with a thick vulcanized rubber sheet 3, either adhered or unadhered, and the entire surface of which is covered with paper,
It is covered with a thin cutting blade receiving sheet 2 with a smooth surface made of cloth or a resin sheet. The method for manufacturing the poly V belt 21 using the drum in which the surface of the cylindrical drum 1 is sequentially coated with the vulcanized rubber sheet 3 and the cutting edge receiving sheet 2 has already been described in FIGS. 1 and 2. As described in detail, the wide angle canvas 5, the unvulcanized upper adhesive rubber sheet 6, the rope extension 7, the unvulcanized lower adhesive rubber sheet 8, and finally the compressed rubber sheet 9 are laminated in order, The unvulcanized belt molded body 20a was vulcanized integrally with a cylindrical drum, and the sleeve-shaped vulcanized belt molded body 20b was attached to a polishing machine (not shown) together with the drum, and a plurality of band-shaped protrusions 11 were provided on the outer peripheral surface. Using a grinder 12, ribs 9a are formed on 9 parts of the compressed rubber layer of the belt molded body, and the rib-added sulfur belt molded body is transferred to a cutting machine (not shown) together with the drum 1, and the ribs are placed in the valleys of the rib parts. As shown by the dotted line, a cut is made to a predetermined width to reach the cutting blade receiving sheet 2, and the cut belt is removed from the drum 1.
By inverting the poly V belt 21 shown in FIG.
is manufactured. The cutting blade receiving sheet 2 used here is formed to be relatively thin from an economical point of view, so during the belt cutting operation, some parts of the sheet 2 are completely cut, and some of the cutting blades are cut off. Although this resulted in part of the lower vulcanized rubber sheet 3 being damaged,
The cutting edge receiving sheet 2 is replaced every cycle of forming, vulcanizing, polishing, and cutting during belt manufacturing, and the vulcanized rubber sheet 3 cut into thin lines is covered with the cutting edge receiving sheet 2, although it seems new. A series of belt manufacturing operations on a single drum can be repeated only by replacing the thin cutting edge receiving sheet 2.

Next, a third invention for manufacturing the low edge V-belt 22 will be explained using FIGS. 9 and 10.

In the figure, 1 is an iron cylindrical drum, on its outer circumferential surface is a thick vulcanized rubber sheet 3, on its outer circumferential surface is a thick unvulcanized rubber sheet 4, and in addition, on its outer circumferential surface is paper. Thin blade receiving sheets 2 with smooth surfaces made of cloth or resin sheets are sequentially laminated and coated. The method for manufacturing the low edge V-belt 22 using the drum coated with the three sheets 4, 3, and 2 described above is as explained in detail with reference to FIGS. 4 and 5. A compressed rubber sheet 9, a lower unvulcanized adhesive rubber sheet 8, a rope-like tensile body 7, an upper unvulcanized adhesive rubber sheet 6, and finally one to a plurality of wide-angle canvases 5 are sequentially wrapped in a laminated manner. This unvulcanized belt molded body 20a is vulcanized together with the cylindrical drum 1, and the sleeve-shaped vulcanized belt molded body 20b after vulcanization is transferred to the cutting process together with the drum 1, as already explained with reference to FIG. As shown, one round blade cutter 14 is inclined in the direction of the arrow and cuts into the vulcanized belt molded body 20b, and then the other round blade cutter 15 inclined in the opposite direction is similarly cut up to the cutting blade receiving sheet 2, and the base A low edge V-belt 22 having the same shape is manufactured.

The cutting blade receiving sheet 2 used here is formed relatively thin from an economical point of view, so during the belt cutting operation, some parts of the sheet 2 are completely cut, and some parts of the cutting blade are also cut off. reaches a part of the lower unvulcanized rubber sheet 4. Moreover, the cutting blades that reach the unvulcanized rubber sheet are two cutting blades 1 with different inclination angles.
4 and 15, it is difficult for the cutting lines on the rubber sheet surface to perfectly match each cycle, and the cuts are made in a slightly shifted state, so the surface of the rubber sheet located on the bottom surface of the cutting edge receiving sheet 2 becomes ring-shaped. There is a risk that uneven lines will be generated on the sheet surface due to the cutting and removal, and that this will cause unevenness to occur on the belt surface (more precisely, on the bottom of the belt) during the next cycle of vulcanization. Even if a cutting edge receiving sheet 2 with a smooth surface is laminated and coated, it is difficult to remove the unevenness that occurs on the belt surface. Therefore, in consideration of the special circumstances of diagonal cutting by the cutting blade, in the present invention, a flexible unvulcanized rubber sheet 4 is disposed directly under the cutting blade receiving sheet 2, so that cutting can be performed in each cycle. Even if the cutting position shifts, due to the flexibility of the unvulcanized rubber, the damaged part of the cut will be immediately restored, and a smooth surface will always be maintained, working together with the cutting edge receiving sheet 2 to create an accurate and efficient low edge V-belt. subsidize the manufacturing of

As described above, this group of inventions is characterized in that a replaceable cutting blade receiving sheet with a smooth surface is always interposed between a belt molded body wrapped and molded on the surface of a cylindrical drum at a position in contact with the belt molded body. We designed the belt to be able to perform a series of processes such as forming, vulcanizing, polishing, and cutting continuously on a single drum. By eliminating the breakage of cutting blades and forming drums, which was a major hindrance to continuous work on a single drum,
We were able to produce the following effects.

Since belts can be manufactured continuously on a single drum, the number of man-hours can be significantly reduced, work efficiency can be improved, and product costs can be reduced as a result.

By arranging a cutting blade receiving sheet directly under the belt molded body for each cycle, no traces of damage caused by the cutting blades are left on the surface of the cylindrical drum or vulcanized rubber sheet, and traces are always transferred to the surface of the belt, which is a product. There's nothing to do.

The presence of the cutting edge receiving sheet in contact with the belt molded body plays the role of a deaeration sheet during vulcanization, making it possible to produce a belt with a smooth surface and a good appearance.

By carrying out a series of operations from forming to cutting on a single drum, dimensionally stable belts can be mass-produced.

The presence of the cutting edge receiving sheet makes it easy to remove the finished product (belt) from the cylindrical drum.

It can be expected to have good quality in many areas such as this and have a great effect on improving work efficiency.

[Brief explanation of drawings]

FIG. 1 is a partial cross-sectional view showing the manufacturing mode of the first invention, FIG. 2 is a partial cross-sectional view showing the polishing process subsequent to FIG. 1, and FIG. A perspective view of a part of the poly V belt obtained by the first and second inventions, FIG. 4 is a partial cross-sectional view showing another manufacturing mode of the first invention, and FIG. FIG. 6 is a partial cross-sectional view showing the cutting process continued from FIG. A diagram corresponding to FIG. 1 showing the manufacturing mode of the second invention, FIG.
9 is a diagram corresponding to FIG. 1 showing the manufacturing mode of the third invention that implements this invention, and FIG. 10 is a partial cross-sectional view showing the polishing process continued from FIG. FIG. In the figure, 1 is a cylindrical drum, 2 is a cutting blade receiving sheet,
3 is a vulcanized rubber sheet, 4 is an unvulcanized rubber sheet, 2
0a is an unvulcanized belt molded body, 20b is a vulcanized belt molded body, 21 is a poly V belt, and 22 is a low edge V belt.

Claims (1)

[Claims] 1. Covering the entire outer periphery of a cylindrical drum with a replaceable cutting blade receiving sheet, forming a belt laminated molded product on the sheet, and performing subsequent vulcanization, polishing, cutting operations, etc. A method for manufacturing a power transmission belt, characterized in that a series of manufacturing steps are performed continuously on the same drum. 2. The method for manufacturing a power transmission belt according to claim 1, wherein the cutting edge receiving sheet has a wall thickness and is made of paper, cloth, resin sheet, etc. with a smooth surface. 3. A vulcanized rubber sheet is interposed inside a replaceable blade receiving sheet that covers the entire outer circumference of the cylindrical drum, and a belt laminate molded body is formed on the blade receiving sheet, followed by vulcanization, polishing, A method for manufacturing a power transmission belt, characterized in that a series of manufacturing processes such as cutting operations are performed continuously on the same drum. 4. The method for manufacturing a power transmission belt according to claim 3, wherein the cutting edge receiving sheet is made of paper, cloth, resin sheet, etc., which is thin and has a smooth surface. 5 A vulcanized rubber sheet is interposed on the inner side of the replaceable cutting edge receiving sheet that covers the entire outer circumference of the cylindrical drum, and an unvulcanized rubber sheet is interposed on the surface of the vulcanized rubber sheet, and a belt is placed on the cutting edge receiving sheet. A method for manufacturing a power transmission belt, characterized in that a series of manufacturing steps such as forming a laminated molded product, followed by vulcanization, and cutting are performed continuously on the same drum. 6. The method for manufacturing a power transmission belt according to claim 5, wherein the cutting edge receiving sheet is made of paper, cloth, resin sheet, etc., which is thin and has a smooth surface.