JPS5828080B2 - rotary cutting machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary cutting machine used for continuously cutting sheet materials such as paper, film, cloth, etc. in the transverse direction.

Conventional equipment of this type consists of a cutter roll that holds a knife and a cylindrical counter roll made of hardened steel, but it requires a large amount of torque to cut, and the equipment is large and heavy. There was a drawback.

These shortcomings in conventional devices are mainly due to the following reasons.

In other words, in conventional devices of this type, the cutting edge of the cutter roll is held parallel to its rotation axis, and the counter roll is also arranged parallel to the cutter roll, so the cutting edge of the cutter roll is held parallel to the sheet material to be cut. The moment it is pressed against the counter rolls, the entire width is simultaneously cut.

Therefore, cutting requires a large torque, and both the cutter roll and counter roll require large rigidity to avoid the tendency to deflect in the center, so both parts are large and heavy. I didn't get it.

In order to avoid such drawbacks, it is effective to twist the cutting edge of the cutter roll so that it cuts sequentially from one end to the other.

However, in order to do this, it is necessary to finish the cutting edge of the cutter roll into an accurate spiral shape, and in order to process the highly hard cutting edge material into this shape, a special high-precision machine tool must be used. Therefore, in practice, this machining is very difficult and expensive, and there is another difficulty in that it is not easy to re-grind the cutting edge if it becomes worn.

The present invention aims to provide an inexpensive rotary cutting machine that is lightweight, compact, and has low cutting torque, which has a structure that has a so-called perforation hole while keeping the cutting edge of the cutter roll in a straight shape that is easy to process. That is.

The present invention will be explained with reference to the drawings. Figures 1 to 3 show embodiments of the present invention.

A straight cutting edge 2 fixed to a cutter roll 1 is arranged obliquely in the rotational direction with respect to its axis.

The counter roll 3 is rotatably supported by the left and right side plates 4.5 through bearings, and the cutter roll 1 is rotatably supported by pins 6 against the side plates 4 and 5, also by bearings. It is rotatably supported and pressed by a spring 9 in the direction of pressure contact with the counter roll 3.

The surfaces 10.11 of the holding plate 7.8 are in contact with the surfaces 12.13 of the side plates 4 and 5, respectively, and are related to the maximum distance at which the cutting edge 2 of the cutter roll can contact the counter roll 3 even at the minimum position of the rotation radius. It has been stopped.

The cutter roll 1 receives power through a chino (not shown) and is rotationally connected to the counter roll 3 by gears 12 and 13, and the circumferential speed of the cutting edge 2 and the counter roll 3 is controlled by the feed rolls 14 and 15. It is driven at a speed approximately equal to the feeding speed of the sheet material to be cut (not shown) being fed.

In the rotary cutting machine according to the present invention configured as described above, the cutting edge diameter of the cutter roll is not necessarily constant, but combined with the structure in which it is in elastic contact with the counter roll, it is possible to cut the sheet material to be cut sequentially from one end to the other. Cut securely.

Therefore, compared to conventional rotary cutting machines of this type, the torque required for cutting is reduced, and the cutting machine can be made smaller and lighter because it requires less rigidity.

Now, in such a rotary cutting machine based on the present invention, if we pay attention to the rotation of the cutter roll and the accompanying change in the relative position of the counter roll, these relationships are shown in Figures 4 and 4. FIG.

In Fig. 4, the point where the straight cutting edge 2 of the cutter roll 1 first contacts the counter roll 3 (cutting start end) is P.
point, the intermediate position where the radius of rotation of cutting edge 2 is minimum is point Q,
The end of the cut is point R.

FIG. 5 shows a change in the distance X between the cutter roll 1 and the counter roll 3 as the cutter roll 1 rotates θ.

When the cutter roll 1 rotates, first, the cutting edge point P touches the counter roll 3 (point A), the center of the cutter roll 1 axis, P
The distance from each other is expanded until the point and the counter roll 3 are lined up in a straight line (point B), and then the distance X changes as the rotational diameter of the cutting edge 2 changes (point B → point C → point D),
The distance X decreases until the cutting end point R leaves the counter roll 3 (point E).

When the cutter roll 1 and the counter roll rotate at a relatively low speed, the rotation angles θ and X change according to the relationship described above and do not occur in particular.

However, when the cutter roll 1 and the counter roll rotate on a raised floor, the following problem occurs.

That is, in the example illustrated in FIGS. 4 and 5, the sheet material to be cut is cut from point A to point D, but at point B, the distance X that had been increasing suddenly decreases. A gap is created momentarily between the blade edge 2 and the counter roll, resulting in a portion that cannot be cut.

In order to avoid such problems that occur in the case of high-speed drive, the rotation radius of the cutting edge 3 relative to the counter roll 3 should always increase from the beginning of cutting to the end of cutting, as shown in Figure 6. It is effective to do so.

FIG. 7 shows the rotation angle θ of the cutter roll 1 and the distance X between the cutter roll 1 and the counter roll in this case.

Cutting is performed from point F to point G, and since the rotation radius of the cutting edge 2 is constantly increasing during this period, no defective cutting occurs due to the above-mentioned reason.

However, the distance There is often a risk that a gap will be created between the blade edge and the counter roll, making it impossible to cut.

In other words, after the cutting edge of the cutter roll comes into contact with the counter roll, the distance Even though the time) was O, it causes a change in the distance according to the shape of the cutting edge (0÷〉0), so there is no impact on the speed of the cutter roll at this point (point F). , No matter how you adjust the distance between both rolls in the standby state, it is impossible to avoid the occurrence of a shock.

In order to avoid this, the cutting edge of the cutter roll should be arranged so that it is on a plane parallel to the axis that is in contact with the cutting edge locus circle at the cutting start end.

FIG. 8 shows the rotation θ of the cutter roll and the distance X from the counter roll in this case.

At this time, the cutting start point (point H) causes a change in relative position X almost continuously, and no impact is generated.

Therefore, stable cutting can be achieved even at high speed rotation.

The cutter roll and counter roll are rotationally connected by gears, but if these gears have the same number of teeth, the cutting edge of the cutter roll will always be in pressure contact with the counter roll at the same position to perform cutting. Abrasion easily occurs on the surface of the counter roll.

In order to avoid this, it is effective to have a structure in which the number of teeth of each gear is slightly different so that cutting is not performed continuously at the same location on the counter roll.

If the number of teeth of the cutter roll gear is 01 and that of the counter roll is n3, then when the least common multiple of nl and n3 is N, cutting will be performed at the same location on the counter roll only every (N/n3) cuts. This means that the counter roll has sufficient durability.

In this case, if the surface hardness of the counter roll is made somewhat lower than the hardness of the cutting edge of the cutter roll,
This has the effect of reducing wear and tear on the cutting edge and maintaining the durability of the cutting machine as a whole for a long time.

As explained above, the present invention provides a small, lightweight, and durable rotary cutting machine that has a straight cutting edge and an easy-to-process structure, can cut with low driving torque, and is lightweight and durable. It is something.

[Brief explanation of the drawing]

Figure 1 is a top view of the rotary cutting machine of the present invention, Figure 2 is a side view of Figure 1, Figure 3 is a sectional view showing the SS cross section of Figure 1, and Figure 4 is the rotary cutting machine of the present invention. 5 is a graph showing the operation of FIG. 4, FIG. 6 is a schematic diagram showing another embodiment of the rotary cutting machine of the present invention, and FIG. 7 is a schematic diagram for explaining the positional relationship of the rolls. FIG. 6 is a graph showing the operation, and FIG. 8 is a graph showing the operation of still another embodiment of the rotary cutting machine of the present invention.

Claims (1)

[Claims] 1. A rotary cutting machine consisting of a cutter roll having a knife edge and a highly hard cylindrical counter roll arranged parallel to the axis of the cutter roll, with the cutting edge of the cutter roll being straight and relative to its axis. The cutter roll is tilted in the circumferential direction and fixed, and the straight cutting edge of the cutter roll is arranged so that the diameter of the cutting edge monotonically increases with respect to the counter roll from the beginning of cutting to the end of cutting.The counter roll and cutter roll are connected by a spring. A rotary cutting machine characterized by a structure in which the cutting edge of the cutter roll is always pressed in the pressure direction and is locked at a position where the cutting edge of the cutter roll is always in contact with the counter roll across the entire cutting width. 2. The rotary cutting machine according to claim 1, characterized in that the straight cutting edge of the cutter roll is arranged on a plane parallel to the axis that is in contact with the cutting edge locus circle at the cutting start end.