JPH0655486A - Rubber component cutter - Google Patents

Abstract

PURPOSE:To provide a cutter which can cut a rubber sheet at a low angle easily. CONSTITUTION:This rubber component cutter consists of a fixing table 15; a knife driving device 13 journalled oscillatable to the fixing table 15 and a pair of oscillation links 14a and 14b; and the knife 4 whose both ends are jouranlled oscillatable to the ends of both oscillating links 14a and 14b respectively; and by making the cutter end of one side oscillating link 14a journalled oscillatable by the tip of a piston 13a of the knife driving device 13, the knife 4 is operated in a circular arc form.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber component cutter (hereinafter, simply referred to as a cutter). More specifically, it relates to a cutter capable of cutting an inner liner of a tire, a rubber component such as a sidewall or a tread, or an unvulcanized rubber sheet at a low bevel angle (low angle) of 30 ° or less.

[0002]

2. Description of the Related Art Conventionally, it has been tried to cut the above rubber component (hereinafter represented by a rubber sheet) with a cutting surface having a low angle as much as possible. This is a low-angle cut surface S of the rubber sheet R as shown in FIG.
This is because the area of connection between the rubber sheets R becomes large when cut so as to form a sheet, so that it is easy to assemble and the sealing property when bonded is improved. As a result, it is easy to automate the connection between the rubber sheets R, and it is expected that the automation of molding saves manpower and improves the productivity.

A hot knife (a knife heated to about 200 ° C.) 51 as shown in FIG. 6 is generally used for low-angle cutting such as the above. The blade 52 of the hot knife 51 is formed in a V shape as shown in the figure, and cuts the rubber sheet R in the vicinity of the inner portion 53.

That is, as shown in FIG. 7A, both sides of the portion of the rubber sheet R to be cut are held by the clamps 54 and stretched. Then, as shown in FIG. 7B, the blade 52 of the hot knife 51 is brought into contact with and positioned on the side of the rubber sheet R, and then the rubber sheet R is completely pushed down. The cutting at the low bevel angle is performed by tilting the hot knife 51 so as to approach the rubber sheet R in parallel.

[0005]

However, when low bevel angle cutting is performed using the conventional hot knife 51, the following fatal problems occur.

That is, as shown in FIG. 7C, the rubber sheet R is pressed by the pressing force from the hot knife 51.
The surface is deformed so that it intersects the hot knife 51 at a right angle. Therefore, no matter how the hot knife 51 is set at an acute angle with respect to the surface of the rubber sheet R, the above-mentioned deformation is restored after cutting, and the actual cutting angle becomes larger than the initial setting angle of the hot knife 51. (See (d) of FIG. 7).

This is because the relative resistance that the rubber sheet R receives from the hot knife 51 at the time of push cutting is made as small as possible, and it is also caused by the shape of the hot knife 51. Further, this phenomenon becomes more remarkable as the rubber sheet R is cut at a low angle. The reason is as follows.

(1) Since the contact length between the rubber sheet R and the blade edge of the hot knife 51 becomes long, the relative resistance received from the hot knife 51 becomes large. (2) Since the contact area between the rubber sheet R and the hot knife 51 is increased, the temperature of the hot knife 51 is easily lowered. (3) Since the hot knife 51 is tilted, the distance between the clamps 54 (W in FIG. 6B) must be increased, and the rubber sheet R is more easily deformed.

The present invention has been made in order to solve the above problems, and the friction between the rubber sheet and the knife at the time of cutting is greatly reduced, and the deformation of the rubber sheet is eliminated, so that the low bevel of the rubber sheet is reduced. The purpose is to provide a cutter capable of cutting.

[0010]

A cutter of the present invention comprises a knife portion, a moving means for moving the knife portion in a direction in which a component perpendicular to the blade edge and a component parallel thereto are combined, In the vicinity of the blade edge, there is provided a tensioning means for stretching the rubber component, which is an object to be cut, in a state of being bent in a slightly V shape from a straight line parallel to the blade edge.

The cutter is interlocked with the stretching means,
The rubber component is provided with a conveying means for supplying and discharging the rubber component, and the stretching means holds both sides of the rubber component in a state of bending in a dogleg shape in the vicinity of the part where the blade edge enters. It is preferably composed of a clamp which can be moved between a cutting position and a non-cutting position where the rubber component is released from its holding after cutting.

The rubber component in the claims is a concept including a rubber material having various shapes such as a sheet shape, a prismatic shape, and a cylindrical shape.

[0013]

According to the cutter of the present invention, the rubber sheet is bent in a dogleg shape in a line parallel to the blade edge of the knife portion, and the knife portion penetrates into the portion where the tensile stress is generated. Since both sides of the rubber sheet are cut apart, both sides of the rubber sheet are separated from both sides of the knife portion. Therefore, the resistance against the advance of the knife portion is significantly reduced, and the contact area between the knife portion and the rubber sheet is reduced, so that the temperature of the knife portion is not easily lowered.

On the other hand, when the rubber sheet is cut, the knife portion is moved in a direction in which both components, that is, the direction perpendicular to the edge of the blade and the direction parallel to the blade edge, are combined. Since the blade is cut, the cutting angle of the knife portion with respect to the rubber sheet is extremely small, and the cutting resistance is significantly reduced. Furthermore, since the cutting surface area and contact time of the rubber sheet that come into contact per unit interview of the knife portion are considerably smaller than those of the conventional hot knife 51, the temperature of the knife portion is less likely to decrease.

As a result of the above, according to the cutter of the present invention, it is possible to easily perform cutting at a low angle (30 ° or less) cutting surface, and like the conventional hot knife 51, a rubber sheet is cut during cutting. There is no problem of sticking and cutting.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the cutter of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a front view showing an embodiment of the cutter of the present invention, FIG. 2 is an operation explanatory view of a knife portion in the cutter of FIG. 1, and FIGS. 3 to 4 are operation explanatory views of the cutter of FIG. .

In FIG. 1, reference numeral 1 is a cutter, which is a sheet feeding portion 2 for feeding the rubber sheet R to be cut and a sheet fixing portion 3 for holding the rubber sheet R.
And a cutting section 5 having a knife 4 for cutting the rubber sheet R, and a sheet unloading section 6 for delivering the cut rubber sheet R.

The sheet feeding section 2 is a rubber sheet R at a substantially constant speed.
Is constituted by a supply roller 7 that rotates so as to feed the sheet to the sheet fixing portion 3 by a set length (direction of arrow A).

The sheet fixing section 3 includes a driving section (not shown) for the supply roller 7 and a knife driving apparatus described later.
It is composed of a top clamp 8 and a bottom clamp 9 that interlock with 13 to hold the rubber sheet R under pressure at the same time when the supply roller 7 stops and release the holding when the rubber sheet R is cut. FIG. 1 shows that the top clamp 8 pushes the rubber sheet R so as to bend it into a dogleg shape, and the leaf spring 9a
Shows the holding state with some tension applied. While the rubber sheet R is being supplied, both clamps 8 and 9 are constructed so that they can be opened by the clamp driving device 10 as in the state shown in FIG. 4, and in that state the rubber sheet R becomes a straight line. . The top clamp 8 is divided into a front top clamp 8a and a rear top clamp 8b so as to form a gap 11 into which the knife 4 enters. The contact surfaces of the front top clamp 8a and the rear top clamp 8b with the rubber sheet R are inclined at a slight angle to each other, whereby the rubber sheet R is bent into a dogleg shape just at the gap 11. .

The cutting portion 5 is interposed between the knife 4 which can be heated by the plate heater 12, the knife driving device 13, and the knife driving device 13 so as to move the knife 4 in an arc shape. A pair of swing links 14
a and 14b (see also FIG. 2).
In the present embodiment, both the clamp driving device 10 and the knife driving device 13 are air cylinders, but they may be electric motors, solenoids or the like.

Now, the movement of the knife 4 will be described with reference to FIG. The knife driving device 13 and the pair of swing links 14a and 14b are pivotally supported by a fixed base 15 so as to be swingable. The tip ends of the pair of swing links 14a and 14b are swingably supported on both ends of the knife 4, respectively. The tip of the piston 13a of the knife driving device 13 is swingably connected to the other end of the long swing link 14a. The piston 13a is reciprocated in the directions of arrows B and C.

As shown in the figure, if the piston 13a of the knife driving device 13 is driven in the direction of arrow B, a long swing link 14a is obtained.
And the pivotal part of the knife 4 moves in an arc in the D direction. As a result, the knife 4 also moves in an arc in the D direction. By this movement, the blade edge 4a of the knife 4 cuts into the rubber sheet. Conversely, if the piston 13a moves in the C direction, the knife 4 moves in the arrow E direction and cuts the rubber sheet in the same manner as described above.

Next, as shown in FIG. 1, the sheet unloading section 6 is composed of a belt conveyor 16 which is driven in a direction for sending the cut rubber sheet R to the outside of the cutter 1 (direction of arrow F in the figure). .

In the present embodiment, the sheet supply unit 2 is composed of the supply roller 7 and the sheet unloading unit 6 is composed of the belt conveyer 16. However, the present invention is not limited to these. Various known transporting means can be appropriately selected.

Next, the operation of the cutter 1 described above will be described.

First, both the top and bottom clamps 8 and 9 are opened by the clamp driving device 10, and the rubber sheet R is fed from the sheet feeding portion 2 toward the sheet fixing portion 3 by a set length. Then, as shown in FIG. 3, the rubber sheet R is clamped and held by the clamps 8 and 9 while tension is applied by the leaf spring 9a. Then, the knife 4 heated to about 200 ° C. is set at a predetermined angle with respect to the surface of the rubber sheet R to be cut, and is moved in an arc by the knife driving device. Then, the portion of the rubber sheet R bent by the clamps 8 and 9 in a dogleg shape is cut so that the knife 4 slices. When the circular arc movement of the knife 4 is completed, the rubber sheet R is cut, and then both the clamps 8 and 9 are opened to release the holding of the rubber sheet (see FIG. 4). The cut downstream rubber sheet R is carried out by the belt conveyor 16. Simultaneously with the carry-out, the rubber sheet R is newly supplied by the set length from the sheet supply unit 2, and the above-described operation is repeated.

According to the present cutter 1 as described above, the rubber sheet can be cut automatically and continuously at a low angle. Of course, not only the sheet-shaped rubber but also a rectangular column or a columnar rubber block can be cut at a low angle. In that case, the stroke of the knife 4 may be adjusted appropriately.

[0029]

When the cutter of the present invention is used, the friction between the knife and the rubber component is greatly reduced when the rubber component is cut, and the deformation of the rubber component is eliminated, so that the rubber component can be cut with an extremely low cutting angle. Can be cut.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a cutter of the present invention.

FIG. 2 is an operation explanatory view of a knife portion in the cutter of FIG.

FIG. 3 is an operation explanatory view of the cutter of FIG.

FIG. 4 is an operation explanatory view of the cutter of FIG. 1.

FIG. 5 is an explanatory diagram of a cut surface of a rubber sheet.

FIG. 6 is a plan view showing an example of a knife portion in a conventional cutter.

FIG. 7 is an explanatory view of the operation of the knife portion of FIG.

[Explanation of symbols]

 1 Cutter 2 Sheet Supply Section 3 Sheet Fixing Section 4 Knife 4a Blade Edge 5 Cutting Section 6 Sheet Unloading Section 8 Top Clamp 9 Bottom Clamp 11 Interval 13 Knife Drive Device 14a Swing Link 14b Swing Link 15 Fixing Stand R Rubber Sheet S Cutting surface

Claims (2)

[Claims] 1. A knife portion, a moving means for moving the knife portion in a direction in which a component perpendicular to the blade edge and a component parallel to the blade edge, and an object to be cut near the blade edge. The rubber component has a tensioning means for tensioning the rubber component from a straight line parallel to the blade edge in a slightly bent shape, and cutting the rubber component at an acute surface with respect to the surface. Rubber component cutter for doing. 2. A conveying means for supplying and sending out a rubber component, which is interlocked with the stretching means, is provided, and the stretching means closes a portion of the rubber component where a blade edge enters. The rubber component cutter according to claim 1, wherein the rubber component cutter is composed of a clamp that can be moved between a cutting position in which both sides are held in a bent state and a non-cutting position in which the holding is released after cutting the rubber component.