JP3790962B2 - Manufacturing method of toothed belt - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a toothed belt.
[0002]
[Prior art]
As a manufacturing method of a toothed belt, it is comprised, for example from the following AE processes.
A. A cylindrical mold having tooth forming grooves on its outer peripheral surface is wound in the order of a stretchable canvas, a core wire, a thick unvulcanized rubber sheet, and a stretchable canvas.
B. A cylindrical mold wound with stretchable canvas, core wire, unvulcanized rubber sheet and stretchable canvas is placed in a vulcanized can, and steam of a predetermined pressure is introduced into the can to form a semi-vulcanized belt. Manufacture the body.
[0003]
Here, in the semi-vulcanized belt molded body, by heating and pressurizing with steam, the unvulcanized rubber sheet flows and about half the amount exceeds the core wire, and the inner elastic canvas is pressed by the rubber. Thus, unfinished teeth are formed following the shape of the tooth forming groove, and the other half of the amount remains outside the core wire.
C. The cylindrical mold is taken out from the vulcanizing can, cooled to room temperature, and then the semi-vulcanized belt molded body is removed from the cylindrical mold.
D. The semi-vulcanized belt molded body is stretched between two toothed pulleys having teeth corresponding to unfinished teeth formed on the semi-vulcanized belt molded body.
E. A semi-vulcanized belt molded body stretched between toothed pulleys by a pair of upper and lower pressurizing and heating molds having a tooth shape while rotating the semi-vulcanized belt molded body while rotating the toothed pulley. To form teeth on both sides.
[0004]
However, in the above manufacturing method, since it is necessary to flow one thick rubber sheet in the step B, the heating temperature and the applied pressure must be increased. The vulcanization degree of the whole rubber becomes high and the fluidity is lowered. Therefore, if a complete tooth is formed by the pressurizing / heating mold in the E step, the rubber is damaged, and as a result, the running life as a belt is shortened.
[0005]
[Problems to be solved by the invention]
Therefore, an object of the present invention is to provide a method for manufacturing a toothed belt that can form a complete helical tooth or a immediate tooth without damaging the rubber part and has a sufficient running life.
[0006]
[Means for Solving the Problems]
(Invention of Claim 1)
In the manufacturing method of the toothed belt according to the present invention, the first canvas sheet is covered with a cylindrical mold, the first rubber sheet, the core wire, and the second rubber sheet are wound on the cylindrical mold in this order, and further on the second rubber sheet. The process of covering the mold with a second canvas jacket that stretches in the circumferential direction of the mold, and applying the low pressure and low temperature from the outer surface side of the second canvas jacket to cause the second rubber sheet to flow in a state of being hardly vulcanized, thereby integrating these members A step of forming the cylindrical intermediate product, and the second canvas jacket surface by sandwiching the demolded intermediate product with two flat plate press dies heated to a temperature at which the first and second rubber sheets are vulcanized The step includes molding the tooth or the immediate tooth on the side, and the step of removing the tooth or the state in which the immediate tooth is molded from the flat plate pressing mold and cutting the sheet into a predetermined width.
(Invention of Claim 2)
In the method for manufacturing a toothed belt according to the present invention, after the first canvas is preformed into a corrugated shape, the first rubber sheet is preformed at a temperature that hardly vulcanizes according to the shape of the first canvas after the preforming. The first canvas and the first rubber sheet are integrally formed with a band-shaped integrated object having a temporary tooth portion, a cylindrical mold having a tooth forming groove on the outer peripheral surface, and the tooth forming groove has a temporary tooth. A step of winding the belt-shaped integrated object in a manner in which the portion is fitted, winding the core wire and the second rubber sheet in order on the first rubber sheet, and expanding and contracting in the mold circumferential direction on the second rubber sheet A step of covering the second canvas jacket, and applying a low pressure and low temperature from the outer surface side of the second canvas jacket to cause the second rubber sheet to flow toward the tooth forming groove side in a hardly vulcanized state. Rubber sheet, core wire, second rubber sheet, second canvas A step of forming a cylindrical intermediate product integrated with the jacket, and the intermediate product after demolding are clamped by two flat plate press dies heated to a temperature at which the first and second rubber sheets are vulcanized. (2) A step of molding a tooth or immediate tooth on the canvas jacket surface side, and a step of removing the state in which the helical tooth or the immediate tooth is molded from a flat plate press die and cutting it to a predetermined width. It is supposed to be.
(Invention of Claim 3)
The method for manufacturing a toothed belt according to the present invention relates to the invention according to claim 1 or 2, wherein the intermediate product that has been removed from the mold is passed over a pair of pulleys and the pulleys are rotated to rotate at a predetermined pitch. The first and second rubber sheets are sandwiched between two flat plate press dies heated to a temperature at which the first and second rubber sheets are vulcanized, so that teeth or immediate teeth are molded on the second canvas jacket surface side.
(Invention of Claim 4)
The method for manufacturing a toothed belt according to the present invention relates to the invention according to claim 1, wherein the first canvas jacket has elasticity in the mold circumferential direction, and the removed intermediate product is stretched over a pair of pulleys. The first or second canvas jacket surface is made to rotate by a predetermined pitch by rotating the pulley and sandwiched between two flat plate press dies heated to a temperature at which the first and second rubber sheets are vulcanized. The teeth are to be molded on the side or immediately.
[0007]
The operation and effect of the method for manufacturing a toothed belt of the present invention will be described in the section of the embodiment of the present invention below.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described with reference to the drawings shown as embodiments.
Embodiment 1
FIG. 1 is an enlarged view of a cross section of a toothed belt B having a tooth on one side.
[0009]
As shown in FIGS. 1 and 2, the toothed belt B includes a first rubber layer 2 serving as a back plate portion, a second rubber layer 4 having a helical tooth portion 40 and a tooth bottom portion 41, Consists of a core wire 3 provided between the second rubber layers 2, 4, a first canvas 1 that covers the surface of the first rubber layer 2, and a second canvas 5 that covers the surface of the second rubber layer 4. Has been.
[0010]
Here, the above-described toothed belt B is manufactured by the following steps (1) to (5).
(1). 3. Setting process of material on cylindrical mold 70 As shown in FIG. 4, the cylindrical mold 70 having no tooth forming groove as shown in FIG. 3 is covered with the first canvas jacket 1A, and then the first canvas jacket. The first rubber sheet 2A, the core wire 3, and the second rubber sheet 4A are wound on 1A, and then a second canvas jacket 5A having stretchability in the mold circumferential direction is covered.
(2). The cylindrical mold 70 in which each material is set as shown in the forming step (1) of the intermediate product B1 is put into the vulcanizing can 73 as shown in FIG. 5, and the second canvas as shown in FIG. The second rubber sheet 4A is caused to flow by applying a low pressure and low temperature (pressure 0.5 to 0.7 MPa, 50 to 110 ° C.) only from the outer surface side of the jacket 5A, and the first canvas jacket 1A and the first one as shown in FIG. A cylindrical intermediate product B1 in which the 1 rubber sheet 2A, the core wire 3, the second rubber sheet 4A, and the second canvas material 5A are integrated is formed.
[0011]
Since the intermediate product B1 is molded by applying low pressure and low temperature (pressure 0.5 to 0.7 MPa, 50 to 110 ° C.) only from the outer surface side of the second canvas material 5A, the second rubber sheet 4A flows. Most of it is not vulcanized. That is, both the second rubber sheet 4A and the first rubber sheet 2A are hardly vulcanized. (3). Belt Teeth Molding Step First, the intermediate product B1 is removed from the cylindrical mold 70 (demolding).
[0012]
Next, as shown in FIG. 7, the removed intermediate product B1 is passed over a pair of pulleys P and P, and the pulleys P and P are rotated so as to rotate at a predetermined pitch. 2 The second canvas jacket is clamped by two flat plate press dies 80, 81 heated to the temperature at which the rubber parts corresponding to the rubber sheets 2A, 4A are vulcanized (maintained constant at 130-180 ° C). Mold teeth on the 5A side.
[0013]
After a certain period of time, the vulcanization of the first and second rubber sheets 2A and 4A and the corresponding rubber parts is completed, but before the first and second rubber sheets 2A, 2A, Since both 4A are hardly vulcanized, the fluidity is not lowered, and the rubber part is formed into a complete helical tooth without being damaged by the flat plate press die 80. Therefore, the toothed belt formed through the subsequent steps has a sufficient running life.
(4). In the cutting step, the one in which the teeth are molded is removed from the flat plate press dies 80, 81 and cut into a predetermined width.
(5). After the step (4), the toothed belt B having the teeth to be turned over is completed.
[0014]
In the toothed belt B described above, the first canvas 1 is the first canvas jacket 1A, the first rubber layer 2 is the first rubber sheet 2A, and the second rubber layer 4 is the second rubber sheet 4A. The canvas 5 is formed by a second canvas jacket 5A.
[Embodiment 2]
FIG. 8 is an enlarged cross-sectional view of the toothed belt B formed with a tooth on one side and an immediate tooth on the other side, and FIG. It is a fragmentary perspective view.
[0015]
As shown in FIGS. 8 and 9, the toothed belt B includes a second rubber layer 4 having a helical tooth portion 40 and a tooth bottom portion 41, and a first rubber layer 2 composed of a tooth portion 20 and a tooth bottom portion 21. The core 3 provided between the first and second rubber layers 2, 4, the first canvas 1 covering the surface of the first rubber layer 2, and the surface of the second rubber layer 4. The second canvas 5 is made up of.
[0016]
Here, the above-described toothed belt B is manufactured by the following steps (1) to (6).
(1). In this step, as shown in FIG. 10, a tooth portion 61 provided on the outer periphery of the pre-formed toothed drum 60 and a tooth portion 63 provided on the outer periphery of the toothed roller 62 are provided. However, a device that engages and cooperates is used, and the preformed toothed drum 60 and the toothed roller 62 are rotated in the directions indicated by arrows A and B, respectively.
[0017]
As shown in FIG. 10, the first canvas material 1 </ b> B is supplied to the preformed toothed drum 60 so as to surround a part of the periphery of the preformed toothed drum 60 and is introduced into the engagement region with the toothed roller 62. At this time, the first canvas material 1B is preformed into a corrugated shape by the cooperative operation of both the tooth portions 61 and 63. The first canvas material 1 </ b> B is supplied to the pre-formed toothed drum 60 so that the stretchable yarn is perpendicular to the rotation axis of the pre-formed toothed drum 60.
[0018]
Next, as shown in FIG. 11, a steel belt 64 is applied to a part of the periphery of the pre-formed toothed drum 60 with an appropriate pressing force so as to run at the same speed as the peripheral speed of the pre-formed toothed drum 60. It is done. The first rubber sheet 2B is supplied between the pre-formed toothed drum 60 and the steel belt 64, whereby the first canvas material 1B and the first rubber sheet 2B after pre-forming are integrated. That is, the first rubber sheet 2B is pressed by the steel belt 64 and preformed according to the shape of the first canvas material 1B after the preforming, and the first canvas material 1B and the first rubber sheet 2B are integrated. A band-like integrated object B2 is obtained.
[0019]
In addition, as shown in FIGS. 11 and 13, the preformed belt-like integrated object B2 has temporary tooth portions 20 ′ and tooth bottom portions 21 alternately formed. These temporary tooth portions 20 ′ and tooth bottom portions 21 are formed. The first canvas material 1B is coated following the shape of the above.
(2). Setting process of material to cylindrical mold 70 As shown in FIG. 12, the cylindrical mold 70 having the tooth forming groove 71 on the outer peripheral surface, as shown in FIG. Is wound around the belt-like integrated object B2 for one round.
[0020]
Subsequently, as shown in FIG. 13, the core wire 3 and the second rubber sheet 4B are wound in this order on the first rubber sheet 2B of the strip-like integrated body B2, and the mold circumferential direction is further wound on the second rubber sheet 4B. Is covered with a second canvas jacket 5B having elasticity.
(3). As shown in the step (2) of forming the intermediate product B3, the cylindrical mold 70 in which each material is set is put into the vulcanizing can 73 (see FIG. 5) and only from the outer surface side of the second canvas jacket 5B. The second rubber sheet 4B is made to flow by applying low pressure and low temperature (pressure 0.5 to 0.7 MPa, 50 to 110 ° C.), and the first canvas material 1B, the first rubber sheet 2B, and the core wire as shown in FIG. 3. A cylindrical intermediate product B3 in which the second rubber sheet 4B and the second canvas jacket 5B are integrated is formed. In this state, the intermediate product B3 is formed with teeth 20 ″ (immediate teeth) that are hardly vulcanized on the inner peripheral surface side but are close to the final form.
[0021]
In addition, since the intermediate product B3 is molded by applying low pressure and low temperature (pressure 0.5 to 0.7 MPa, 50 to 110 ° C.) only from the outer surface side of the second canvas material 5B, the second rubber sheet 4B flows. Most of it does not vulcanize. That is, both the second rubber sheet 4B and the first rubber sheet 2B are in a state of being hardly vulcanized.
(4). Belt Teeth Molding Step First, the intermediate product B3 is removed from the cylindrical mold 70 (demolding).
[0022]
Next, as shown in FIG. 15, the removed intermediate product B3 is passed over a pair of toothed pulleys P ′ and P ′, and the toothed pulleys P ′ and P ′ are rotated to rotate the pitch of the teeth 20 ″. Each of the first and second rubber sheets 2B, 4B and the corresponding rubber portion is sandwiched between two flat plate press dies 80B, 81B heated to a temperature (130 to 180 ° C.). The teeth are formed on the second canvas jacket 5B surface side, and the teeth are immediately molded on the first canvas material 1B surface side.
[0023]
After a certain period of time, the vulcanization of the rubber parts corresponding to the first and second rubber sheets 2B and 4B is completed, but before the first and second rubber sheets 2B and 2B are formed by the flat plate pressing dies 80B and 81B, Since 4B is hardly vulcanized, the rubber part on the second rubber sheet 4 side is not damaged, and the complete tooth 40 is obtained by the flat plate press die 80B, while the rubber part on the first rubber sheet 2 side is not damaged. The complete straight tooth portion 20 is formed by the flat plate press die 81B without being damaged. Therefore, the toothed belt formed through the subsequent steps has a sufficient running life.
(5). In the cutting process, the tooth and the state in which the teeth are immediately formed are removed from the flat plate press dies 80B and 81B and cut into a predetermined width.
(6). After the step (5), when turned over, the toothed belt B having the teeth on the inside and the teeth immediately on the outside is completed.
[0024]
In the toothed belt B, the first canvas 1 is made of the first canvas material 1B, the first rubber layer 2 is made of the first rubber sheet 2B, and the second rubber layer 4 is made of the second rubber sheet 4B. The canvas 5 is formed by the second canvas jacket 5B.
(Other embodiments)
In the first embodiment, if the first canvas jacket 1A has elasticity in the mold circumferential direction, and if the first canvas jacket 1A is formed with helical teeth, the turning over step (5) is unnecessary. Become.
[0025]
Moreover, in Embodiment 1, the tooth | gear may be immediately formed in the single side | surface of a belt.
[0026]
Further, in the second embodiment, teeth or immediate teeth may be formed on both sides of the belt.
[0027]
【The invention's effect】
Since the present invention is configured as described above, it has the following effects.
[0028]
As is clear from the contents of the column of the embodiment of the invention, it is possible to provide a manufacturing method of a toothed belt that can form a perfect tooth or a straight tooth without damaging the rubber part and has a sufficient running life. It was.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a toothed belt according to a first embodiment of the present invention.
FIG. 2 is a perspective view of the toothed belt.
FIG. 3 is a perspective view of a cylindrical mold having no tooth forming groove on the outer peripheral surface used for forming the intermediate product B1 of the first embodiment.
FIG. 4 is a cross-sectional view showing a state in which a first canvas jacket, a first rubber sheet, a core wire, a second rubber sheet, and a second canvas jacket are set in the cylindrical mold.
FIG. 5 is a perspective view of a vulcanizing can used for forming the intermediate product B1 of the first embodiment.
6 is a cross-sectional view showing a state where an intermediate product is formed by applying low pressure and low temperature from the second canvas jacket side in the state of FIG. 4;
FIG. 7 is an explanatory view showing a procedure for molding a tooth on one side of the intermediate product.
FIG. 8 is a sectional view of a toothed belt according to a second embodiment of the present invention.
FIG. 9 is a perspective view of a toothed belt according to the second embodiment.
FIG. 10 is an explanatory view showing a state in which a first canvas material is pre-formed into a corrugate by a pre-formed toothed drum and a toothed roller.
FIG. 11 is an explanatory view showing a state in which a band-shaped integrated object is formed from a first canvas material and a first rubber sheet.
12 is a perspective view of a cylindrical mold having tooth forming grooves on an outer peripheral surface used for forming the intermediate product B3 of Embodiment 2. FIG.
FIG. 13 is a cross-sectional view showing a state in which a strip-shaped integrated body made of a first canvas material and a first rubber sheet, a core wire, a second rubber sheet, and a second canvas jacket are set in the cylindrical mold.
14 is a cross-sectional view showing a state in which an intermediate product is formed by applying low pressure and low temperature from the second canvas jacket side in the state of FIG.
FIG. 15 is an explanatory view showing a procedure for forming a tooth on one side of the intermediate product.
[Explanation of symbols]
B Toothed belt B1 Intermediate product B2 Strip-like integrated object B3 Intermediate product P Pulley P 'Toothed pulley 1A First canvas jacket 1B First canvas material 2A First rubber sheet 2B First rubber sheet
20 'temporary tooth part 3 core wire 4A 2nd rubber sheet 4B 2nd rubber sheet 5A 2nd canvas jacket 5B 2nd canvas jacket
70 Cylindrical mold
71 tooth forming groove
80,81 flat plate press mold
80B, 81B Flat plate press mold

Claims (4)

A cylindrical mold is covered with a first canvas jacket, and a first rubber sheet, a core wire, and a second rubber sheet are wound on the cylindrical mold in this order, and the second rubber sheet is stretchable in the mold circumferential direction. A step of covering the canvas jacket, a step of applying a low pressure and low temperature from the outer surface side of the second canvas jacket, causing the second rubber sheet to flow in an almost unvulcanized state, and forming a cylindrical intermediate product integrating these members; The intermediate product thus removed is pressed between two flat plate press dies heated to a temperature at which the first and second rubber sheets are vulcanized to form a tooth or immediate tooth on the second canvas jacket surface side. A method for manufacturing a toothed belt, comprising: a step; and a step of removing a helical tooth or a state in which a tooth is immediately formed from a flat plate pressing die and cutting to a predetermined width.   After the first canvas is pre-shaped into a corrugated shape, the first rubber sheet is pre-formed at a temperature at which the first rubber sheet is hardly vulcanized according to the shape of the first canvas after the pre-forming, and the first canvas, the first rubber sheet, Forming a band-shaped integrated object having temporary tooth portions integrated with each other, and winding the band-shaped integrated object in a manner in which the temporary tooth portions are fitted into the tooth forming grooves in a cylindrical mold having tooth forming grooves on the outer peripheral surface. A step of rotating, a step of winding a core wire and a second rubber sheet on the first rubber sheet in order, and covering the second rubber sheet with a second canvas jacket having elasticity in the mold circumferential direction; , Applying a low pressure and low temperature from the outer surface side of the second canvas jacket to cause the second rubber sheet to flow toward the tooth forming groove side in a state of being hardly vulcanized, the first canvas, the first rubber sheet, the core wire, the second rubber sheet, Cylindrical middle with integrated second canvas jacket And pressing the intermediate product that has been removed with two flat plate press dies heated to a temperature at which the first and second rubber sheets are vulcanized to form teeth on the second canvas jacket surface side. Manufacturing a toothed belt comprising: a step of immediately forming a tooth; and a step of removing a helical tooth or a state in which the immediate tooth has been formed from a flat plate press die and cutting it to a predetermined width. Method. Two flat plate presses that are heated to a temperature at which the first and second rubber sheets are vulcanized so that the intermediate product that has been demolded is passed over a pair of pulleys and rotated to rotate at a predetermined pitch. 3. The method for manufacturing a toothed belt according to claim 1, wherein a tooth or immediate tooth is formed on the second canvas jacket surface side by clamping with a mold.   The first canvas jacket has elasticity in the mold circumferential direction, the intermediate product that has been removed from the mold is passed over a pair of pulleys, and the pulleys are rotated to rotate at predetermined pitches. 2. A tooth or an immediate tooth is formed on the first or second canvas jacket surface side by pressing between two flat plate press dies heated to a temperature at which the rubber sheet is vulcanized. The manufacturing method of the toothed belt of description.

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