JPS5914157Y2 - Single rotation seat cutter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cutter used for cutting roll paper or filter into arbitrary lengths in devices such as copying machines, facsimile machines, and office printers.

For example, as described in Japanese Utility Model Publication No. 48-5909, such a cutter has a structure consisting of a rotating blade and a fixed blade that cuts the sheet material while pressing the cutting edge crosswise against the rotary blade using a spring. be.

Driving the rotary blade by rotating the rotary blade once in such a cutter is widely used as a driving method when cutting while the cutter is traveling because it is unlikely to cause jams (paper jams) even if the sheet material to be cut is cut while it is traveling. ing.

However, when the rotary blade of a conventional cutter is driven one revolution, there is a serious drawback in that the durability of the cutter is significantly reduced due to the following reasons.

A wheel having the same cylindrical surface as the cutting edge of the rotary blade is integrally attached to the cutting start end of the rotary blade of the cutter as a guide for engagement of the cutting edges of both the rotating blade and the fixed blade.

When the rotary blade is in standby mode, the cutting edge of the fixed blade is pressed against this wheel, and when the rotary blade is driven, the cutting edge of the fixed blade slides on the outer peripheral surface of this wheel, and then the cutting edge of the fixed blade slides on the outer circumferential surface of this wheel. It engages with the cutting edge to perform cutting.

The wheel body for guiding the cutting edge is made of the same high-hardness material as the cutting edge, and in the case where the rotating blade is driven to reciprocate by the rotary solenoid and return spring described in the above-mentioned Japanese Utility Model Publication No. 48-5909. The sliding friction range between the wheel and the fixed blade is about 5 to 15 at most, but when rotating the rotary blade once, the range of sliding friction between the wheel and the fixed blade is about 3.
Since sliding friction occurs over a range of 00° or more, there is an unavoidable tendency for early wear to occur only at the portion of the fixed blade that contacts the cutting edge with the wheel.

The wheel of the rotary blade and the cutting edge part of the fixed blade that come into contact with this part play an important role in guiding the engagement of both cutting edges, and if there is significant wear and tear on this part, the cutter as a whole will eventually deteriorate. This will impede the functionality of the

The present invention eliminates these drawbacks by shortening the friction distance between the wheel of the rotary blade and the cutting edge of the fixed blade, thereby providing a cutter with a long life.

To explain the present invention with reference to the drawings, in FIGS. 1 and 2, a fixed blade 1 is supported by a leaf spring 2, and its cutting edge 3 is mounted at a position that slightly interferes with the locus circle 5 of the cutting edge of the rotary blade 4 in the free state. It will be done.

The rotary blade 4 is provided with a guide ring 6 at its cutting start end.

The guide ring 6 is attached eccentrically to the cutting edge 7 side with respect to the cutting edge trajectory circle 5 of the rotary blade, and the area near the cutting edge 7 is finished with the same cylindrical surface 5 as the cutting edge.

Now, in the one-rotation type sheet cutter having such a structure and based on the present invention, when the rotary blade 4 rotates in the cutting direction (arrow A direction), the cutting edge 3 of the fixed blade 1 first comes into contact with the guide ring 6, and then the cutting edges mutually bite. After cutting sheets 1 to 8 together,
As the radius of the guide wheel 6 decreases, it loses contact and the plate b
remains in the free state position of 2.

In the one-rotation type sear 1 to cutter based on this invention, the contact friction between the guide ring of the rotary blade and the cutting edge of the fixed blade occurs in a very small range before and after cutting, so naturally there is little wear in this area, and it is durable. It can be used as a cutter with high performance.

In addition, with this single-rotation type sheet cutter, the rotating blade and fixed blade do not come into contact with each other except during and before and after cutting, so there is no friction loss between the rotating blade and the fixed blade, which reduces the power required to drive the rotating blade. It also has the characteristic of being able to

FIG. 3 shows another embodiment of the shape of the guide wheel, in which the guide wheel 9 has a notch 10 at a corresponding portion after the start of cutting.

When the guide ring is shaped like this, there is no contact between the guide ring and the cutting edge of the fixed blade after cutting, which further improves durability.

FIG. 4 shows yet another embodiment of the present invention, in which the cutting edge 12 of the rotary blade 11 and the guide ring 13 share a common axis 01.
The cutting edge 13 is eccentrically formed with respect to the drive axis 02 of the rotary blade in the direction of the maximum radius.

When the rotary blade is shaped like this, the outline of the guide ring becomes a smooth continuous curve, and even when the rotary blade is rotated at high speed, more stable and quiet cutting can be performed.

As explained above, the present invention provides a single-rotation type sheet cutter that has a simple structure in which the fixed blade is supported by a leaf spring and the guide ring of the rotary blade is eccentrically shaped, has high durability, and can be driven easily. It is.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of a one-rotation type sheet cutter according to the present invention, and FIG. 2 is a sectional view taken along the SS of FIG. 1. 3 and 4 are cross-sectional views showing other embodiments.

Claims (1)

[Claims for Utility Model Registration] 1. A cutter consisting of a rotary blade that is driven one revolution and a fixed blade that cuts a sheet material while pressing the cutting edge in cross-pressure contact with the rotary blade by a spring, in which the fixed blade is supported by a leaf spring. It is installed in a position where the cutting edge slightly interferes with the cutting edge trajectory circle of the rotating blade in the free state, and the rotating blade is placed at the cutting start end of the rotating blade before the cutting edges of the fixed blade engage with each other and the cutting starts. A single-rotation type sheet cutter characterized by a structure in which a blade edge guide part is provided whose radius gradually increases, becomes the same cylindrical surface as the blade edge just before cutting starts, and quickly reduces the radius after cutting starts. 2. Scope of a claim for registration of a utility model characterized by a structure in which a wheel whose center is eccentric in the direction of the cutting edge of the rotating blade is attached to the cutting start end of the rotating blade, and only the area near the cutting edge is cylindrically ground at the same time as the cutting edge. The single-rotation sheet cutter described in item 1. 3 Attach a wheel whose center is offset toward the cutting edge of the rotary blade at the cutting start end of the rotary blade.After cutting starts, the corresponding part is cut out to provide relief, and only the area near the cutting edge is finished by cylindrical grinding at the same time as the cutting edge. A single-rotation type sheet cutter according to claim 1 of the utility model registration claim characterized by a structure. 4. It is characterized by a structure in which a wheel with the same cylindrical surface as the cutting edge cylindrical surface is provided as a cutting edge guide at the cutting start end of the rotary blade, and the rotary drive shaft of the rotating blade is mounted eccentrically in the direction where the cutting edge has the maximum radius. A single-rotation type sheet cutter according to claim 1 of the utility model registration claim.