JP3069970B2 - Method and apparatus for continuous vulcanization of rubber sheet - Google Patents

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 continuously vulcanizing a rubber sheet, and more particularly to a method for producing a vulcanized rubber sheet with reduced dimensional debris and stable dimensional accuracy. The present invention relates to a method and an apparatus for continuously vulcanizing a rubber sheet.

[0002]

2. Description of the Related Art Conventionally, as a continuous vulcanizing apparatus for a rubber plate, a blasted main roll 1, a first pressure roll 2, a tension roll 3, a driving roll 4, and a surface wound around a main roll 1 are used. Blasted steel band 5
And a guide roll 6 of an unvulcanized rubber sheet Wa, and the molded unvulcanized rubber sheet Wa is continuously inserted into the steel band 5 and the main roll 1 while being sandwiched therebetween. It is to be vulcanized.

[0003] Incidentally, as a method of continuously vulcanizing the rubber sheet W in the above-mentioned state, an unvulcanized rubber sheet Wa is constrained so that both end portions of the unvulcanized rubber sheet Wa do not flow in the width direction during vulcanization. There are known a method of arranging a gauge ring or a gauge belt at both ends of a vulcanized rubber sheet Wa for vulcanization, and a method of vulcanizing by solid pressing without using the gauge ring or the gauge belt. The method of vulcanizing using the above-described gauge ring or gauge belt has a short life and requires time and effort for placement and insertion. Therefore, a method of vulcanizing by solid pressing is generally used.

[0004]

However, in the method of vulcanizing by solid pressing, since both end portions of the rubber sheet W are not restrained at the time of vulcanization, the rubber at both end portions flows during the vulcanization. However, there is a problem that the thickness of the ear portion becomes thinner than the thickness of the center portion or the portion becomes porous, and vulcanization is performed to eliminate the difference in thickness between the center portion and the ear portion of the rubber sheet W. Later, the width of the ear trim of the rubber sheet W had to be widened, so that there was a problem that ear trim debris increased and wasted.

The present invention has been devised in view of such a conventional problem, and suppresses the flow of rubber in both ears at the time of vulcanization of a rubber sheet, and eliminates porosity in both ears.
An object of the present invention is to provide a method and an apparatus for continuously vulcanizing a rubber sheet, which can significantly reduce the amount of material trimmed by reducing trim of ear trims and can make the thickness of the rubber sheet uniform in the width direction. It is the purpose.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention achieves both ends of an unvulcanized rubber sheet during vulcanization immediately before the unvulcanized rubber sheet is put between a main roll and a steel band. The gist of the invention is to provide a restraining means for restraining the flow of rubber in the part. Further, as the restraining means, in addition to installing a semi-vulcanizing device, a canvas of a predetermined width is disposed on at least one of the upper surface or the lower surface of both ears of the unvulcanized rubber sheet. .

[0007]

The present invention is constituted as described above, and immediately before the unvulcanized rubber sheet is inserted between the main roll and the steel band, the both ends of the unvulcanized rubber sheet are semi-vulcanized to a predetermined width. After that, the rubber sheet is put between the main roll and the steel band to perform the main vulcanization, so that the flow of rubber in both ears of the rubber sheet can be suppressed.

A canvas of a predetermined width is disposed on at least one of the upper and lower surfaces of both ears of the unvulcanized rubber sheet, and the rubber sheet is inserted between the main roll and the steel band in this state. By performing the main vulcanization, the flow of rubber in both ears can be restrained during the vulcanization.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings. The same components as those of the conventional example are denoted by the same reference numerals, and description thereof will be omitted. FIG. 1 is a schematic front view of a continuous vulcanizing apparatus for a rubber sheet W embodying the present invention, wherein 1 is a blasted main roll, 2 is a first pressing roll, 4 is a driving roll, and 5 is a first vulcanizing roll. A pressure-rolled roll 2, a tension roll (not shown), a drive roll 4, and a steel band whose surfaces are blasted around the main roll 1 are blasted, and 6 is a guide roll for an unvulcanized rubber sheet Wa.

Immediately before the unvulcanized rubber sheet Wa is introduced between the main roll 1 and the steel band 5, the vulcanization restricts the flow of rubber in the both ears Wx of the unvulcanized rubber sheet Wa during vulcanization. A restraining means 7 is provided. For example, as shown in FIG. 2, the restraining means 7 includes rotating heating drums 8 on the upper and lower surfaces of both ears Wx of the unvulcanized rubber sheet Wa.
a, 8b are arranged to provide both ears Wx of the unvulcanized rubber sheet Wa.
A rotary heating drum system for semi-curing a predetermined width, and as shown in FIG. 3, a microwave and electron beam vulcanizing device having a U-shaped cross section on the upper and lower surfaces of both ears Wx of an unvulcanized rubber sheet Wa. 9
a, 9b for semi-vulcanization, and as shown in FIG. 4, infrared heaters 10a, 10b on the upper and lower surfaces of both ears Wx of unvulcanized rubber sheet Wa for semi-vulcanization. There is a method of sulfurizing.

Further, another restraining means 7 for restraining the flow of rubber in both ear portions Wx of the unvulcanized rubber sheet Wa during vulcanization.
In place of the above semi-vulcanization method, as shown in FIG. 5, a canvas 11 having a width of 10 mm to 50 mm is provided on at least one of the upper surface or the lower surface of both ears Wx of the unvulcanized rubber sheet Wa.
a and 11b are arranged, and in this state, an unvulcanized rubber sheet Wa is inserted between the main roll 1 and the steel band 5 to perform the main vulcanization. Further, as another embodiment, as shown in FIG. 6, the strip-shaped vulcanized rubber 12a, 12
There is also a method in which b is disposed on both sides of the unvulcanized rubber sheet Wx to restrict the flow of the ear rubber. In this case, as in the related art, the ear trim of the vulcanized rubber sheet can be effectively used without using a gauge ring or the like.

Next, the effect of vulcanization using the restraining means 7 of the semi-vulcanization method as described above, and the effect of at least one of the upper surface or the lower surface of both ears Wx of the unvulcanized rubber sheet Wa. The effect of vulcanization by disposing the canvases 11a and 11b will be described with reference to the graphs of FIGS. FIG. 7 is a graph illustrating the effect of vulcanization using the constraining means 7 of the semi-vulcanization method in comparison with a conventional vulcanization method, and illustrates a 5.0 mm thick natural rubber sheet (standard value 5.
0 mm, +0.2 mm, −0.1 mm), when semi-curing at 120 ° C for 2 minutes, and comparing with the conventional solid pressing vulcanization method,
In the conventional method, it is necessary to trim both end portions Wx of the vulcanized rubber sheet W by about 10% of the length in the width direction, but in the present invention, it is almost unnecessary to trim.
That is, by semi-vulcanizing the both ears Wx of the unvulcanized rubber sheet Wa in advance by the semi-vulcanizing restraint means 7, the flow of the rubber in the ears Wx can be restrained, and thereby the thickness in the width direction is reduced. This was substantially uniform, the dimensional accuracy in the width direction of the vulcanized rubber sheet W was stabilized, and unnecessary trim trim was reduced.

FIG. 8 shows that at least one of the upper and lower surfaces of both ears Wx of the unvulcanized rubber sheet Wa has a width of 40 mm.
FIG. 7 is a graph illustrating the effect of vulcanizing by disposing canvas 11a, 11b such as cloth excellent in heat resistance of 3.0 mm, and a natural rubber sheet having a thickness of 3.0 mm (standard value: 3.0 mm). ±
0.1 mm) at 120 ° C. for 2 minutes and a conventional solid pressing vulcanization method. Ear Wx
Need to be trimmed about 10% of the length in the width direction, according to the present invention, there is almost no need to trim, whereby the thickness in the width direction becomes substantially uniform, and the vulcanized rubber sheet W The dimensional accuracy in the width direction was stabilized, and unnecessary trim trim was reduced.

In the above semi-vulcanization method, the degree of semi-vulcanization is slightly different depending on the thickness (mm) of the rubber sheet and the width of the rubber sheet, and as shown in FIG. At 2.4 mm, semi-curing time is about 1 minute and thickness is 2.6
In mm, the semi-vulcanization time was about 2 minutes, and when the thickness was 2.75 mm, the semi-vulcanization time was about 3 minutes.

[0015]

According to the present invention, as described above, when the rubber sheet is vulcanized, the flow of the rubber in the both ears can be suppressed, and the porosity in the both ears can be eliminated. Accordingly, it is possible to greatly reduce ear trim debris, thereby reducing waste of material, and to stabilize dimensional accuracy by making the thickness of the rubber sheet uniform in the width direction.

[0016]

[Brief description of the drawings]

FIG. 1 is a schematic front view of an apparatus for continuously vulcanizing a rubber sheet embodying the present invention.

FIG. 2 is a sectional view showing a first embodiment of the restraining means.

FIG. 3 is a sectional view showing a second embodiment of the restraining means.

FIG. 4 is a sectional view showing a third embodiment of the restraining means.

FIG. 5 is a sectional view showing another embodiment of the restraining means.

FIG. 6 is a sectional view showing another embodiment of the restraining means.

FIG. 7 is a graph illustrating the effect of vulcanization using a constraining means based on a semi-vulcanization method in comparison with a conventional example.

FIG. 8 is a graph illustrating the effect of vulcanizing by arranging a canvas on at least one of the upper and lower surfaces of both ears of an unvulcanized rubber sheet, and a graph illustrating a comparison with a conventional case.

FIG. 9 is an explanatory diagram showing the degree of semi-vulcanization in the semi-vulcanization method.

FIG. 10 is a schematic front view of a conventional continuous vulcanizing apparatus for a rubber sheet.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Blasted main roll 2 1st press roll 3 Tension roll 4 Drive roll 5 Blasted steel band 6 Guide roll 7 Restraining means 8a, 8b Rotary heating drum 9a, 9b Microwave and electron beam vulcanizing apparatus 10a, 10b Infrared heater Wa Unvulcanized rubber sheet 11a, 11b Canvas 12a, 12b Strip-shaped vulcanized rubber with ear trim W W Vulcanized rubber sheet Wx Both ears

(56) References JP-A-4-78521 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B29C 35/00-35/14

Claims (5)

(57) [Claims] 1. A continuous rubber sheet for vulcanizing by feeding a molded unvulcanized rubber sheet between a main roll whose surface is blasted and a steel band wound around the main roll. In the vulcanization method, immediately before the unvulcanized rubber sheet is inserted between the main roll and the steel band, after semi-curing both ears of the unvulcanized rubber sheet by a predetermined width, the main roll and the steel band are vulcanized. A continuous vulcanization method for a rubber sheet, wherein a vulcanization of a rubber sheet is carried out between the vulcanization and the main vulcanization. 2. A continuous rubber sheet for vulcanizing by feeding a formed unvulcanized rubber sheet between a main roll whose surface is blasted and a steel band wound around the main roll. In the vulcanization method, a canvas of a predetermined width is disposed on at least one of the upper surface or the lower surface of both ears of the unvulcanized rubber sheet, and in this state, the rubber sheet is placed between the main roll and the steel band. A continuous vulcanization method for a rubber sheet, wherein the vulcanization is performed after the introduction. 3. A main roll having a blasted surface, and a first pressure roll, a tension roll, a driving roll, and a steel band having a blasted surface wound around a main roll, respectively. In a continuous rubber sheet vulcanizing device, in which a molded unvulcanized rubber sheet is charged and vulcanized between a steel band, an unvulcanized rubber sheet is charged between the main roll and the steel band. Immediately before the vulcanization, a restraining means for restraining the flow of rubber in both ears of the unvulcanized rubber sheet during vulcanization is provided. 4. The continuous vulcanizing apparatus for a rubber sheet according to claim 4, wherein a semi-vulcanizing apparatus is provided as the restraining means. 5. The rubber sheet according to claim 4, wherein a canvas having a predetermined width is provided on at least one of the upper surface and the lower surface of both ears of the unvulcanized rubber sheet as the restraining means. Continuous vulcanization equipment.