JP3411083B2 - Method and apparatus for cutting unvulcanized 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 for cutting an unvulcanized rubber sheet and an apparatus therefor, and more particularly to a method for cutting an unvulcanized rubber sheet in a pressure molding step during cutting of the unvulcanized rubber sheet. It is possible to cut the cutting line by cutting the unvulcanized rubber sheet on the cutting side with a predetermined tension after forming the thin part that can be cut when pulling the cutting part without separating the part. And a device for cutting the unvulcanized rubber sheet.

[0002]

2. Description of the Related Art Conventionally, in a tire manufacturing process, a long unvulcanized rubber sheet such as an inner liner is cut into a rubber sheet having a predetermined length, and the cut rubber sheet is wound around a molding drum. There is a step of crimping and joining both ends thereof. In this joining step, the two ends of the cut rubber sheet to be joined have good step uniformity h at both ends Wa of the rubber sheet W as shown in FIG. 12 in order to improve the uniformity and joining accuracy of the tire. As described above, both end portions Wa of the rubber sheet W are cut obliquely with respect to the thickness direction of the rubber sheet W, and the step difference of the splice portion (bonding portion) S of the rubber sheet W is minimized as shown in FIG. Should be.

However, in the conventional blade, the cutting angle β
Is less than 15 °, and in order to maintain the adhesive strength of the adhesive surface, lap splicing is unavoidable as shown in FIG.

[0004]

[Means for Solving the Problems] A rubber sheet W as described above.
In the cutting of, the hot knife and the circular cutter are used, and the hot knife and the circular cutter are cut with a tilt as much as possible in order to reduce the step of the splice portion S, but it is very difficult to cut with a tilt of 20 ° or less. There was a problem.

Recently, with the advent of ultrasonic cutters, it is possible to cut at an angle of up to about 15 °, but above 15 °, a sheet gauge (thickness) is required to perform the cut face alignment. Cut surface length is 8 mm for 2 mm or less
Only the following can be obtained, and there is a problem that it is difficult due to reasons such as the cut length system of the sheet and lack of adhesive strength due to variations and insufficient adhesive surfaces. The thickness of general seats is 1.0 to 1.2 mm for passenger cars and 1.8 mm to 2.2 mm for trucks.

Further, as a method of obtaining a cut surface with a low angle, for example, as disclosed in Japanese Patent Laid-Open No. 4-220332, a pressing plate (die) having a mountain shape is used to press and cut. A molding method and apparatus have been proposed, but by pressing with a mountain-shaped pressure plate, elongation in the longitudinal direction occurs, and after processing or cutting, there was a problem in feeding the leading edge of the continuous sheet. .

That is, when the unvulcanized rubber sheet is cut by pressing (cutting by pressing while molding), the cut end becomes wrinkled due to residual internal stress after peeling from the mountain-shaped pressure plate (mold), or becomes wavy. There is a problem that it flutters, and when the continuous sheet is fed in, the thin part of the tip of the mold will break, which will adversely affect the spliced state later.Furthermore, the tip of the mountain part of the mold was contacted with the lower mold. Since the cutting is performed in the state, there is a problem that the mold release material (Teflon coating) coated on the mold is worn or peeled off, and the life is shortened.

The present invention has been devised in view of the above conventional problems, and does not separate the cut portion of the unvulcanized rubber sheet in the pressure molding step when cutting the unvulcanized rubber sheet, The unvulcanized rubber sheet after cutting is formed by forming a thin portion that can be cut when the cut portion is pulled, and then separating and cutting by pulling the unvulcanized rubber sheet on the cutting side with a predetermined tension. It is possible to effectively prevent the cutting end from being deformed or broken, and to improve the spliced state of the unvulcanized rubber sheet later.In addition, the unvulcanized rubber sheet is connected to the front and back of the embossing device. The unvulcanized rubber sheet between the presses can be easily loaded and unloaded between the presses, and there is no contact between the mountain-shaped pressure plate to be pressed and the fixed base, so the life of the pressure plate can be extended. Unvulcanized It is an object to provide a cutting method and device for a seat.

[0009]

In order to achieve the above-mentioned object, the present invention has a mountain-shaped pressure plate and a fixing base in which a cut portion of an unvulcanized rubber sheet is heated in a conveying line of the unvulcanized rubber sheet. With the die, the die is pressed into a substantially V-shaped cross-section by pressing, and the thickness of the cutting line of the cutting portion is formed into a thin portion that can be cut when the unvulcanized rubber sheet on the cutting side is pulled by a predetermined tension. The apparatus is installed, and the unvulcanized rubber sheet unloading line behind the embossing apparatus is equipped with a separating device that pulls and cuts the unvulcanized rubber sheet on the cutting side along the cutting line of the cutting portion. It is what

In addition, a vertical embossing device for press-molding from at least one of the vertical direction is installed on the unvulcanized rubber sheet conveyed in the horizontal state, or the unvulcanized rubber sheet conveyed in the vertical state is unvulcanized. It is also possible to install a horizontal embossing device that pressurizes the vulcanized rubber sheet from at least one of the left and right directions. Further, a clamp means for clamping the unvulcanized rubber sheet is installed between the embossing device and the separating device, and a pressure plate for press-molding the cut portion of the unvulcanized rubber sheet has a substantially V-shaped cross section. It is also possible to form the tip of the pressure plate in a concavo-convex shape or in a beak shape along the width direction, in addition to the shape.

[0011]

The present invention is constructed as described above, and presses the cut portion of the unvulcanized rubber sheet conveyed by the carry-in conveyor by the mountain-shaped embossing device to cut the cut line of the cut portion. The thickness of the unvulcanized rubber sheet before and after the cutting line is formed into a thin wall that can be cut when pulled by a predetermined tension, and the front and back surfaces of the cutting line are formed into inclined surfaces, The unvulcanized rubber sheet after cutting is unvulcanized by pulling the unvulcanized rubber sheet on the cutting side in the longitudinal direction with a predetermined tension while holding the front and rear parts of the unvulcanized rubber sheet. It is possible to effectively prevent the cut end portion of the rubber sheet from being deformed or broken, and improve the spliced state of the sheet later. Further, in order to facilitate pulling and cutting, the gauge of the embossing device is adjusted so that the thickness of the cutting line at the cutting portion becomes 0.1 mm to 0.3 mm.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings. The same components as those in the conventional example are designated by the same reference numerals and the description thereof will be omitted. FIG. 1 shows a horizontal embossing device 2 for pressure-molding an unvulcanized rubber sheet W conveyed in a horizontal state according to the present invention by a mountain-shaped pressure plate 1 from at least one of the left and right directions. The schematic front view of the installed cutting device 3 is shown, and the said embossing device 2 carries in the carry-out end part 4a of the carry-in conveyor 4 and the carry-out conveyor 5 which were installed in parallel with a predetermined space | interval and provided the step. Part 5
Clamping means 6 which is installed in the space between a and a, and clamps the unvulcanized rubber sheet W at the bottom of the embossing device 2.
Also, a device 7 for separating the unvulcanized rubber sheet W is installed.

The embossing device 2 is provided with a vertically fixed heated fixing base 9 fixed to a base 8 and the chevron-shaped mount installed opposite to the fixing base 9 so as to be movable back and forth. This pressure plate 1 is composed of a heated pressure plate 1.
Moves back and forth toward the fixed base 9 by the press cylinder 10 and holds the cut portion Wx of the unvulcanized rubber sheet W between the fixed base 9 and the mountain-shaped pressure plate 1 as shown in FIG. Then, it is pressure-molded into a substantially V-shaped cross section, and the cut portion Wx of the unvulcanized rubber sheet W is processed as shown in FIG.

That is, in the embossing device 2, the cut portion Wx of the unvulcanized rubber sheet W is pressure-formed into a substantially V-shaped cross section without being cut off by the fixing base 9 and the pressure plate 1, and the cut portion Wx is formed. The thickness H of the cutting line P-P is formed into a thin portion that can be cut when the unvulcanized rubber sheet W on the cutting side is pulled by a predetermined tension, for example, 0.1 mm to 0.3 mm. When the wall thickness H of the cutting line PP is 0.1 mm or less, it may be cut from the cutting line PP during the molding process or during transportation, and when it is 0.3 mm or more. However, even if it is pulled, it cannot be easily separated, and there is a possibility that defects such as the unvulcanized rubber sheet W stretching or the cut surface deforming may occur.

Further, the pressure plate 1 and the fixing base 9 of the embossing device 2 are provided by a heating means (not shown) in order to easily press-form the cut portion Wx of the unvulcanized rubber sheet W into a substantially V-shaped cross section. It is desirable to keep the temperature constant. The clamping means 6 for clamping the unvulcanized rubber sheet W installed at the lower part of the embossing device 2 is a supply side of the unvulcanized rubber sheet W pressure-molded into a substantially V-shaped cross section as shown in FIG. And is composed of a fixed base plate 11 and a clamp cylinder 12.

The unvulcanized rubber sheet W separating device 7 is also provided.
Is for pulling the cutting side of the unvulcanized rubber sheet W clamped by the clamp means 6 in the horizontal direction to separate it from the cut portion Wx of the unvulcanized rubber sheet W. The upper part of the carry-in portion 5 a of the carry-out conveyor 5 A rotatable separating roll 14 is attached to the tip of a rod 13a of a separating cylinder 13 installed horizontally.

That is, after the unvulcanized rubber sheet W in which the cut portion Wx is pressure-formed by the embossing device 2 into a substantially V-shaped cross section is sent out to the carry-out conveyor 5 side, the supply side of the unvulcanized rubber sheet W is changed. The unvulcanized rubber sheet W is clamped by the clamping means 6 and the cutting side of the unvulcanized rubber sheet W is separated, and the separating cylinder 13 of the device 7 is extended so that the cutting side of the unvulcanized rubber sheet W is separated by the separating roll 14 provided at the tip of the rod 13a. As shown in FIG. 2, the unvulcanized rubber sheet W is cut along the cutting line Wx by cutting the unvulcanized rubber sheet W by a predetermined tension in the direction of the arrow.
At the same time as separating from the end, there is no breakage or wrinkles at the end
It is transferred onto the carry-out conveyor 5.

5 and 6 show the unvulcanized rubber after press-molding the cut portion Wx of the unvulcanized rubber sheet W from the mountain-shaped pressure plate 1 of the embossing device 2 into a substantially V-shaped cross section. An embodiment for peeling the pressure plate 1 from the cut portion Wx without deforming the cut portion Wx of the sheet W, in the embodiment of FIG. 5, the mountain-shaped pressure plates 1a and 1b are thickened from the top portion 1x. The pressure plates 1a and 1b are divided into two parts in the vertical direction so that the pressure plates 1a and 1b can be operated separately by the two press cylinders 10a and 10b.

That is, the cut portion Wx of the unvulcanized rubber sheet W
Of the unvulcanized rubber sheet W by raising one of the pressure plates 1a through the press cylinder 10a with the other pressure plate 1b pressing the cut portion Wx after completion of the molding with the pressure plates 1a and 1b. The pressure plate 1a can be easily peeled off from the cut portion Wx, and then the other pressure plate 1b is lifted from the cut portion Wx to be peeled off.

Further, FIG. 6 shows the pressure plate 1c from the cut portion Wx.
Shows another embodiment for peeling the
After press-molding the cut portion Wx into a substantially V-shaped cross-section, the pressure plate 1c is easily separated from the cut portion Wx by swinging the pressure plate 1c left and right by a predetermined angle α as shown by the chain double-dashed line. Can be done. The swinging means may be configured to support the press cylinder 10 and the rod with a hinge or the like so as to swing. If such a method is adopted, the clamp means 6 can be omitted.

FIGS. 7 (a), (b), 8 and 9 show a chevron shape in which the cutting portion Wx of the unvulcanized rubber sheet W can be easily and accurately cut by the cutting device 7. 7 (a) shows another embodiment of the pressure plate 1 in the shape of a circle,
In the embodiment of (b), the tip portion E of the pressure plate 1d is formed in a concavo-convex shape along the width direction, and the cut portion Wx of the unvulcanized rubber sheet W is added to the pressure plate 1d in a substantially V-shaped cross section. When pressure forming,
The convex portion of the pressure plate 1d contacts the fixing base 9, and the concave portion has 0.1
The unvulcanized rubber sheet W having a thickness of mm to 0.3 mm remains, and as shown in FIG. 8, the cutting line P-P of the cutting portion Wx of the unvulcanized rubber sheet W is connected to one of the uneven portions. Therefore, when the cutting side of the unvulcanized rubber sheet W is formed later and separated by the separating device 7, the connection area becomes smaller than the cut portion Wx of all the unvulcanized rubber sheets W that are connected. Even if the pulling force is small, the cutting can be easily performed, and the cutting line P-P of the cutting portion Wx is deformed to some extent, but can be reliably cut along the P-P line.

In the embodiment shown in FIGS. 9A and 9B, the tip E of the pressure plate 1e is formed into a beak shape, and the pressure plate 1e is formed.
When the cut portion Wx of the unvulcanized rubber sheet W is pressure-molded in e with a substantially V-shaped cross section, when the cutting side of the unvulcanized rubber sheet W is later cut off by the cutting device 7, the unvulcanized rubber sheet W is cut. Concentrated tensile stress is applied to the cut portion Wx of W, and it is possible to easily cut even if the pulling force is small.
The cutting line P-P of x is also unlikely to be deformed, and can be cut along the line P-P without fail.

FIG. 10 shows a multi-stage carry-in conveyor 24a,
The unvulcanized rubber sheets W1 and W2 are conveyed from 24b, and the cut portion Wx of the unvulcanized rubber sheet W is cross-sectionally V-shaped by the embossing device 2 installed in the space between the conveyor 25 and the conveyor. It is formed by pressure molding, and the cut portion Wx is separated by the clamping means 26 and the separating device 27 for the unvulcanized rubber sheet W. In this embodiment, a plurality of unvulcanized rubber sheets W are simultaneously formed into a predetermined shape. It is possible to cut into lengths.

Since the other structure is the same as that of the first embodiment, the same reference numerals are given and the description thereof is omitted. Further, in the above-described embodiment, the horizontal embossing device which press-molds the unvulcanized rubber sheet W conveyed in the vertical state as the embossing device 2 by the pressure plate 1 from at least one of the left and right directions has been described. However, with respect to the unvulcanized rubber sheet W conveyed in the horizontal state, the unvulcanized rubber sheet W has a predetermined length by using a vertical embossing device that press-molds the unvulcanized rubber sheet W from at least one of the vertical direction by the pressure plate 1. It is also possible to cut into pieces.

According to the present invention configured as described above, when the unvulcanized rubber sheet W is cut into a predetermined length, in the embodiment of the present invention, the cut portion Wx of the unvulcanized rubber sheet W is embossed. Clamping means 6 which will be cut later without being cut off by the device 2
In addition, it is pulled by the separating device 7 to be separated from the cut portion Wx. That is, the cut portion Wx of the unvulcanized rubber sheet W conveyed by the carry-in conveyor 4 is pressed by the chevron-shaped embossing device 2 to cut the cut portion Wx.
The thickness H of the cutting line P-P is formed into a thin thickness H that can be cut when the unvulcanized rubber sheet W before and after the cutting line P-P is pulled by a predetermined tension, and the cutting is performed. The front and rear surfaces of the line PP are formed into inclined surfaces.

That is, the thickness H of the cutting line of the cutting portion Wx is
By adjusting the stroke amount of the press cylinder 10 of the embossing device 2 so that the thickness becomes 0.1 mm to 0.3 mm,
The gauge thickness is adjusted, and then, the rear side of the cut portion Wx of the unvulcanized rubber sheet W, that is, the supply side of the unvulcanized rubber sheet W is clamped by the clamp means 6, and the unvulcanized rubber sheet W is cut. The side of the unvulcanized rubber sheet W is pulled by a predetermined tension in the direction of the arrow as shown in FIG. 2 by extending the detaching cylinder 13 of the detaching device 7 and using the detaching roll 14 provided at the tip of the rod 13a. Thus, the cut side of the unvulcanized rubber sheet W is cut off from the cut portion Wx.

An unvulcanized rubber sheet W is obtained by such a method.
Is pulled by a predetermined length along the upper surface of the carry-out conveyor 5 to the side opposite to the carrying side, and the end portion of the unvulcanized rubber sheet W is transferred to the carry-out conveyor 5 at the same time as the cutting. It is possible to effectively prevent the deformation or breakage of the cut end of the sheet W, and to improve the splicing accuracy of the end portion of the unvulcanized rubber sheet W later, and further, the embossing device 2
In the front and rear parts, since the unvulcanized rubber sheet W is suspended, it is possible to absorb the elongation in the longitudinal direction of the unvulcanized rubber sheet W by pressurization, and the unvulcanized rubber sheet W is in a connected state. Therefore, carrying in the unvulcanized rubber sheet W between the presses,
It can be easily carried out.

[0028]

As described above, according to the present invention, the V-shaped cross section is formed in the conveying line for the unvulcanized rubber sheet by the mountain-shaped pressure plate and the fixing base that heat the cut portion of the unvulcanized rubber sheet. Along with pressure molding, the embossing device for molding the thickness of the cutting line of the cutting portion into a thin portion that can be cut when the unvulcanized rubber sheet on the cutting side is pulled by a predetermined tension is installed,
Since the unvulcanized rubber sheet unloading line behind the embossing device is provided with a separating device that pulls and cuts the unvulcanized rubber sheet on the cutting side along the cutting line of the cutting portion, the following excellent It is effective. (A). During the cutting process of the unvulcanized rubber sheet, the unvulcanized rubber sheet is not cut off in the pressure molding process, but is cut into a thin part that can be cut when the cut part is pulled. Since the end of the unvulcanized rubber sheet is transferred to the carry-out conveyor at the same time as separating and cutting by pulling the vulcanized rubber sheet with a predetermined tension, deformation or breakage of the cut end of the unvulcanized rubber sheet after cutting is prevented. It can be effectively prevented. (B). It is possible to improve the splicing accuracy of the unvulcanized rubber sheet later. (C). Since the unvulcanized rubber sheets are connected to each other in the front and rear portions of the embossing device, it is easy to carry in and carry out the unvulcanized rubber sheets between the pressure plate and the fixing base. (D). Since the tip of the chevron-shaped pressure plate does not contact, abrasion and peeling of the coating material can be prevented, and the life of the pressure plate can be extended.

[Brief description of drawings]

FIG. 1 is a schematic front view of a cutting device provided with a horizontal embossing device embodying the present invention.

FIG. 2 is an enlarged front view of a horizontal embossing device, a clamp means, and a separating device.

FIG. 3 is a partially enlarged front view of a horizontal embossing device.

FIG. 4 is a cross-sectional view of a cut portion of an unvulcanized rubber sheet pressure-molded into a substantially V-shaped cross section.

FIG. 5 is an enlarged front view showing an embodiment of an embossing device for omitting a clamp device for a pressure plate of the embossing device.

FIG. 6 is an enlarged front view showing an embodiment of the embossing device for omitting the clamp device by the pressure plate of the embossing device.

7A is a cross-sectional view showing another embodiment of the tip portion of the mountain-shaped pressure plate, and FIG. 7B is a cross-sectional view taken along the line AA of FIG.

8 is a perspective view showing a cross section of a cut portion of the unvulcanized rubber sheet formed by the mountain-shaped pressure plate of FIG. 7. FIG.

9A is a cross-sectional view showing another embodiment of the tip end portion of the chevron-shaped pressure plate, and FIG. 9B is a cross-sectional view taken along the line BB of FIG. 9A.

FIG. 10 is a schematic front view showing another embodiment in which the cutting device has a multi-stage configuration.

FIG. 11 is an explanatory view showing a spliced state of an end portion of an unvulcanized rubber sheet processed by the present invention.

FIG. 12 is an explanatory view showing a spliced state of a terminal portion of a conventional unvulcanized rubber sheet.

[Explanation of symbols]

1 Pressurizing Plate 2 Horizontal Embossing Device 3 Cutting Device 4 Carrying In Conveyor 5 Carrying Out Conveyor 6 Clamping Means 7 Separation Device W Unvulcanized Rubber Sheet Wx Cut Part H Wall Thickness PP Cutting Line β Cutting Angle

─────────────────────────────────────────────────── --Continued from the front page (56) Reference JP-A-58-59830 (JP, A) JP-A-4-220332 (JP, A) JP-A-6-71587 (JP, A) JP-A-62- 121000 (JP, A) JP-A 1-240296 (JP, A) JP-A 7-1399 (JP, A) JP-A 7-1393 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B29D 30/00-30/72 B26F 1/00-3/16 B26D 3/00-3/30

Claims (7)

(57) [Claims] 1. A cutting portion of an unvulcanized rubber sheet conveyed by a carry-in conveyor is pressed by a mountain-shaped embossing device, and the thickness of the cutting line at the cutting portion is sandwiched between the cutting lines. While forming the front and rear unvulcanized rubber sheets into a thin wall that can be cut when pulled by a predetermined tension, the front and rear surfaces of the cutting line are formed into inclined surfaces, and the front and rear parts of the cutting line of the unvulcanized rubber sheet are formed. A method for cutting an unvulcanized rubber sheet, characterized in that the unvulcanized rubber sheet on the cutting side is separated along a cutting line by pulling the unvulcanized rubber sheet on the cutting side in a longitudinal direction with a predetermined tension while being held. 2. The wall thickness of the cutting line of the cutting portion is 0.1 mm.
The method for cutting an unvulcanized rubber sheet according to claim 1, wherein the gauge thickness of the embossing device is adjusted so that the thickness is about 0.3 mm. 3. An unvulcanized rubber sheet conveying line is pressure-molded into a substantially V-shaped cross-section by a heated mountain-shaped pressure plate and a fixed base of a cut portion of the unvulcanized rubber sheet, and the cutting is performed. Installed an embossing device that forms the thickness of the cutting line of the part into a thin part that can be cut when the unvulcanized rubber sheet on the cutting side is pulled by a predetermined tension, and unvulcanized behind the embossing device. A cutting device for an unvulcanized rubber sheet, wherein a separating device for pulling and cutting the unvulcanized rubber sheet on the cutting side along a cutting line of a cutting portion is installed in a rubber sheet unloading line. 4. The unvulcanized rubber sheet according to claim 3, wherein a vertical embossing device for press-molding from at least one of the vertical direction is installed on the unvulcanized rubber sheet conveyed in a horizontal state. Cutting device. 5. The unvulcanized rubber sheet according to claim 3, wherein a horizontal embossing device for press-molding from at least one of the left and right directions is installed on the unvulcanized rubber sheet conveyed in a vertical state. Cutting device. 6. Between the embossing device and the separating device,
The unvulcanized rubber sheet cutting device according to any one of claims 3 to 5 , further comprising a clamp means for clamping the unvulcanized rubber sheet. 7. A pressure plate for pressure-molding a cut portion of the unvulcanized rubber sheet is formed to have a substantially V-shaped cross section, and a tip of the pressure plate is formed to have an uneven shape or a beak shape along the width direction. unvulcanized rubber sheet cutting apparatus according to any one of claims 3 to 6.