JPH0852686A - Sheet material cutting device - Google Patents

Abstract

PURPOSE:To prevent a movable blade from tilt moving while decreasing resistance in a slide part due to a difference between right/left forces of the movable blade from a cutting start to a cutting end, by using a parallel link for supporting the thin plate-shaped movable blade having a cutting edge of hollowing an edge point line into a V shape. CONSTITUTION:A movable blade 1, movable blade material 11, movable blade base metal 13 and a spacer 16 are fastened by using a supporting shaft pin 13 and a plate nut 17 and built, to fix a fixed blade 4 to a side of a paper through window 21 provided in a frame 2 to make a cut sheet pass. Supporting pins 22, 23 are secured to an end part of this frame 2, and supporting pins 14, 15 provided in the movable blade 1 are connected by the first/second links 31, 32 respectively formed with a parallel link 3, to support the movable blade l to the frame 2. Drive force is loaded to the supporting pin 14, to cut a sheet material by downward moving the movable blade 1 in the case of swiveling the parallel link 3 around the supporting pin 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet material cutting device for performing full-width cutting (full cutting) or uncut cutting (partial cutting) of recording paper or a folded continuous sheet wound in a roll shape. The present invention relates to a sheet material cutting device that is mounted on office equipment such as various printers, communication facsimiles, and copying machines, and that cuts by moving a movable blade in a direction perpendicular to a width direction of a fixed blade.

[0002]

2. Description of the Related Art In recent years, office equipment such as communication facsimiles and various printers have been required to be smaller and lighter and have a longer life, and a sheet material cutting device mounted on such office equipment is also Along with the miniaturization of the printer body, the demand for smaller and lighter printers is increasing. Moreover, this sheet material cutting device must have a function of arbitrarily selecting full-width cutting or uncut cutting. For example, in a sheet material cutting device for a home facsimile or a register, if the sheet material is cut to the full width, the separated sheet material will scatter and must be picked up from the floor. Therefore, a portion of the paper is left uncut, and the uncut portion is torn off when necessary to obtain a piece of paper or the like.

On the other hand, a conventional rotary type cutting device, which is often used, is difficult to miniaturize for structural reasons, and it is not possible to partially cut and cut, so that the width of the sheet material is 50 mm or less. Moreover, it could not be installed in a mini-printer or the like that requires a cut-and-cut function. Therefore, as a sheet material cutting device for a printer that can arbitrarily select full cut and partial cut, a cutting device that uses a saw blade-shaped cutting tool, a scissors-type cutting device, and a movable blade and a fixed blade are cross-pressed to each other so that the movable blade is A cutting device commonly known as a guillotine type has been developed that moves substantially at right angles to the cutting edge line of a fixed blade.

A cutting device using a saw blade must keep the cutting edge sharp in order to obtain a smooth cut. In order to solve this problem, as a cutting device which is easily provided with the functions of full cut and partial cut, JP
The cutting devices described in JP-A-289697 and JP-A-4-300198 have been widely used. And
The cutting device disclosed in Japanese Patent Application Laid-Open No. 1-289697 cuts from both ends toward the center while cross-contacting the mutual cutting edges of a thin plate-shaped movable blade having a V-shaped concave edge line and a fixed blade on the other side. Is a device that advances. Furthermore, JP-A-4-3
Japanese Patent No. 00198 discloses a mechanism for smoothly operating a movable blade in a guillotine-type cutting device having a movable blade recessed in a V shape and a fixed blade having a straight blade edge. Has a structure in which links and racks are provided in the vicinity of both left and right ends, and the movable blades and the fixed blades are cut by the tolerance pressure contact with each other.

[0005]

[Patent Document 1] Japanese Patent Application Laid-Open No. 1-28969
In the cutting device described in Japanese Patent Publication No. 7, the sheet is cut by a pair of blades including a movable blade having a V-shaped concave edge line and a fixed blade that presses the edge of the movable blade, so that the same principle as scissors (however, the scissors are Although the shear angle gradually decreases as the cutting progresses, the cutting device of this structure has a highly reliable structure with the shear angle remaining almost unchanged from the beginning to the end of cutting. It is also possible to add the uncut portion.
Conventionally, in this type of cutting device, a slider provided at the center of a movable blade as shown in FIGS. 4 and 5 is configured to reciprocate in a long hole of a thin plate-shaped frame so that the movable blade and the plate can be moved. It is mounted like a sandwich between the nuts.

In order for the slider to reciprocate while sliding in the elongated hole, the slider must have a diameter slightly smaller than that of the elongated hole and be slightly thicker than the frame. . In addition, the slider can slide smoothly if it has an elongated shape as much as possible.
If it is too long and slender, the height of the entire cutting device becomes high, which is not preferable. In addition, since the movable blade is assembled by stacking it on the fixed blade fixed to the frame, the blade edges interfere with each other by a step corresponding to the thickness of the fixed blade, and the interference causes bending of the frame. It has a structure to obtain pressure contact between the blade edges, and at present, this structure is most often used in a cutting device for a mini printer.

However, in this type of guillotine-type cutting device, the slider located near the center of the movable blade slides in the elongated hole of the frame so that the movable blade moves in the direction perpendicular to the cutting edge line of the fixed blade. Due to the reciprocating structure, the length of the slider must be at least about 1/5 of the cutting width for stable parallel movement of the movable blade. The driving force tends to increase because the slider easily receives frictional resistance on the sliding surface of the side surface due to the deviation of the balance between the left and right forces received by the movable blade during cutting. In particular, when the slider length is set to be short, the effect of the difference between the left and right forces exerted on the movable blade becomes noticeable, the driving force increases, and the movable blade tilts in the width direction, resulting in a shear angle on the right and left. Differences occur and stable cutting becomes difficult.

[0008] Further, although guide portions on which the ends of the movable blade slide may be provided on both sides of the movable blade, in this case, when the force exerted on the movable blade is out of balance on the left and right, the movable blade is moved. Galling will occur between the end of the and the guide. In order to solve such a problem, the applicant of the present application has
A cutting device having a structure capable of uniformly applying a driving force to both sides of a movable blade was developed and filed as Japanese Patent Application Laid-Open No. 4-300198. Although the cutting device of this structure has achieved its initial purpose sufficiently, it is structurally necessary to enlarge the base above the movable blade in view of the drawing, and there is a tendency that the entire cutting device becomes tall. The present invention solves the above-mentioned problems of the conventional guillotine-type cutting device, and makes it possible to perform a stable reciprocating motion without tilting the movable blade with a simple structure to enable cutting even with a small driving force, so that a small size is achieved. It is an object of the present invention to provide a sheet material cutting device that can be cut by a drive source and that does not become too tall.

[0009]

The inventor of the present application has studied to eliminate the above-mentioned problems, and has a thin plate-like movable blade having a cutting edge with a V-shaped cutting edge line, and press-contacting the cutting edge thereto. In a cutting device with a structure that consists of a fixed blade that generates a meshing engagement, by using a parallel link as the method of supporting the movable blade, the resistance of the sliding part due to the difference in the left and right force of the movable blade from the start to the end of cutting The present invention has been completed by finding that the number of blades can be reduced and the movable blade can be prevented from tilting.

The present invention can be applied to a mini cutter for a printer having a short cutting width (about 50 mm or less) to a cutter having a cutting width of about 100 to 300 mm used for a fax machine or the like. In a cutting device having a thin plate-shaped movable blade having a V-shaped concave edge line and a fixed blade that presses the blade edge against each other and meshes with each other, two pins provided at the center of the movable blade By connecting the pins fixed to the other frame with two links of the same length to form a parallel link, the movable blade near the support part caused by the difference in left-right balance during cutting. It is characterized in that the sliding resistance generated is reduced, the driving force necessary for the reciprocating motion of the movable blade is minimized, and a stable cutting is maintained by a small driving source.

Specifically, the first aspect of the present invention is specifically as follows.
A thin plate-shaped movable blade having a V-shaped concave cutting edge in the shearing direction, and the movable blade were pressed against each other next to a paper passage window provided in the frame and mounted so that the movable blade slides. A sheet material cutting device comprising a fixed blade and a parallel link mechanism for connecting a support member of the movable blade and the frame. Further, the sheet material cutting device according to the first invention is characterized in that the fixed blade has a straight blade edge line in the shearing direction.

[0012]

According to the sheet material cutting apparatus of the present invention, the blade edges of the thin plate-shaped movable blade having the V-shaped blade line and the fixed blade pressed against the movable blade are pressed from both ends toward the center. The point moves to perform cutting, and the cutting ends at the center of the V-shape. In the present invention, the pressure contact force of the movable blade is a structure obtained by the bending of the frame to which the movable blade is slidably fixed, and the rigidity of the frame is the pressure contact force required to stably cut the paper. Must be generated.
Normally, in a guillotine type cutting device, the movable blade and the fixed blade start cutting from both ends of the paper and end at the central part, but in general, the conventional cutting device moves due to the difference in the balance of left and right loads received at the time of cutting. In many cases, a force that tilts left and right is generated around the center where the blade is slidably supported,
Easy to be unstable. The present invention prevents the tilt of the movable blade by receiving the force generated as the tilt direction at the rotation fulcrum of the two support shaft pins connected to the parallel link.

That is, by setting the two opposite sides (nodes) of the parallel link to have the same length, the movable blade positioned on one side of the parallel link is driven without changing its posture. It is. As a result, the sliding load of the movable blade is extremely small compared to the conventional cutting device in which the posture of the movable blade is restricted by the side surface of the slider and the end of the movable blade, and the loss of driving force is minimized. And the drive source can be made smaller.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to embodiments and drawings. FIG. 1 is an assembly conceptual diagram showing an embodiment of a sheet material cutting device of the present invention, and FIG. 2 is a sectional view thereof. The movable blade material 11 is made of carbon tool steel (JIS SK5) that has a thickness of 0.3 mm and is subjected to quenching and heat treatment, and is provided with a V-shaped recessed movable blade edge 12 having a blade width of 150 mm. The movable blade 1 is formed by assembling the movable blade material 11, the movable base metal 13, the spacer 16 by the spindle pin 13 and the plate nut 17. The spacer 16 is located between the movable blade member 11 and the plate nut 17, is slightly thicker than the frame 2 by about 0.2 mm, and is slidably fitted in the slide hole 24. The fixed blade 4 was fixed to the side of the paper passing window 21 provided in the frame 2 with an adhesive.

Further, support pins 22 and 23 are fixed to the end portions of the frame 2, and the support pins 22 and 23 and the support shaft pin 14, which is a support member for the movable blade provided on the movable blade 1,
15 are connected to each other by a first link 31 and a second link 32 that have the same length and that form a parallel link 3. The movable blade blade materials 11 are pressed against each other by utilizing the elastic effect of the frame 2 according to the thickness of the fixed blade 4. When a driving force is applied to the support shaft pin 14 by a drive source (not shown), the parallel link 3 swings around the support pin 17 as a fulcrum, the movable blade 1 moves downward in the drawing, and passes through the paper passing window 21. The sheet material (not shown) sent by cutting starts from both ends and ends at the central portion.

Even if the load received by the movable blade 1 is unbalanced during cutting, the posture of the movable blade 1 is maintained by the parallel link 3, so that the movable blade 1 is not tilted and can be cut smoothly. Done. Then, the movable blade 1 is not tilted and the posture is maintained, so that the spacer 16
And unnecessary friction between the slide hole 24 and
The cutting can be done without imposing an excessive load on the drive source. FIG. 3 is a front view showing another embodiment of the sheet material cutting device of the present invention. Of the parallel links 3, the second link 32 is provided with a cam shaft 35 to pivotally support the cam 34, and the cam 34 is provided in the first link 31 with a long hole 33.
Slidably fit in. When the cam 34 is swung with the cam shaft 35 as a fulcrum, the parallel link 3 is swung and the movable blade 1 is moved to cut the sheet material.

In this embodiment, the drive source is directly connected to the shafts of the parallel link 3 and the cam 34. However, one end of the parallel link 3 and one end of the cam 34 are extended and the drive source is provided at the tip thereof. Even if they are connected, the same effect can be obtained, and in some cases, the thickness of the sheet material occupied by the cutting device in the traveling direction can be reduced. Although the present invention has been described with the fixed blade having a straight cutting edge line, the same effect can be obtained even if the fixed blade is provided with a V-shaped concave cutting edge, and a larger shear angle can be imparted. It is possible to reduce the force applied to the drive source.

[0018]

As described above, according to the present invention, a thin plate-shaped movable blade having a V-shaped concave cutting edge,
In this guillotine type cutting device consisting of a fixed blade against which the movable blade is pressed, by using a parallel link as a method of supporting the movable blade, the inclination of the movable blade due to the difference in load on the movable blade during cutting is prevented. It was possible to suppress and reduce the sliding resistance, and it became possible to downsize the drive source. Furthermore, since the link that moves the movable blade for cutting can be installed at almost the same position as the height of the movable blade, the space for installing the link can be made extremely small, and the height of the cutting device body can be reduced. It was possible to lower the size, and the cutting device as a whole could be miniaturized.

[Brief description of drawings]

FIG. 1 is an assembly conceptual diagram showing an embodiment of a sheet material cutting device of the present invention.

FIG. 2 is a sectional view of FIG. 1 showing an embodiment of the sheet material cutting device of the present invention.

FIG. 3 is a front view showing another embodiment of the sheet material cutting device of the present invention.

FIG. 4 is a conceptual diagram showing an example of a conventional guillotine-type cutting device.

FIG. 5 shows an example of a conventional guillotine-type cutting device.
FIG.

[Explanation of symbols]

1 movable blade, 11 movable blade material, 12 movable blade tip, 1
3 Movable blade base metal, 14 spindle pin, 15 spindle pin, 16
Spacer, 17 Plate nut, 2 Frame, 21 Paper window, 22 Support pin, 23 Support pin, 24 Slide hole, 3 Parallel link, 31 1st link, 32 2nd
Link, 33 long hole, 34 cam, 35 cam shaft, 4 fixed blade, 41 fixed blade cutting edge

Claims (2)

[Claims] 1. A thin plate-shaped movable blade having a V-shaped concave cutting edge in the shearing direction, and the movable blade slides by being pressed against the movable blade next to a sheet passing window provided in a frame. A sheet material cutting device comprising a fixed blade mounted as described above, and a parallel link mechanism for connecting the supporting member of the movable blade and the frame. 2. The sheet material cutting device according to claim 1, wherein the fixed blade has a straight edge line in the shearing direction.