JPS5916552A - Document shredder - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a document shredding machine, and more particularly to a document shredding machine for shredding discarded documents into chips.

Conventionally, serrated tooth tips are formed on the outer periphery of a rotary cutter that is fitted onto two rotating shafts that are parallel to each other, and the document is pierced by the tooth tips. Document shredding machines have been proposed that cut documents to obtain finely chopped chips. In this shredding machine, spacers are provided between the many cutters to prevent the chips from wrapping around each other.

In the above structure, the chips shredded by the rotary cutter are attached to the wall between the tips of the teeth of the rotary cutter, and as the rotary cutter rotates, the chips are separated from the tips of the teeth between adjacent spacers. Therefore, chips accumulate between adjacent spacers, and eventually the chips accumulated between the spacers become hard and interfere with the outer periphery of the rotary cutter, applying a brake. Therefore, the throughput of the rotary cutter is significantly reduced, and in this case, the spacer tip must be cleaned periodically, resulting in a disadvantage that maintenance thereof is troublesome.

The present invention was developed in view of the above-mentioned circumstances, and includes providing a protrusion for chip removal in the cutting direction of a rotary cutter, and improving its shape and positional relationship with the cutting blade of an adjacent rotary cutter. It is an object of the present invention to provide a document shredding machine that reduces tearing resistance, allows chips to reliably separate from and fall from a rotary cutter, and prevents chips from accumulating between spacers.

The present invention has two rotating shafts that are parallel to each other, and a large number of rotary cutters and spacers are alternately filled with liquid on each shaft, and the rotary cutters on both shafts are arranged so as to mesh with each other. In the document shredding machine, the rotary cutter has tearing blades that protrude radially outward at appropriate intervals on the outer periphery, and a space between adjacent tearing blades on the outer periphery that is larger than the base diameter of the tearing blade. a chip detachment protrusion that protrudes radially outward; the protrusion has a front slope that rises at an obtuse angle in front of the rotational direction of the rotary cutter; The protrusions are arranged so as to protrude into the space formed by the front slope of the protrusion.

Next, the embodiment shown in the drawings will be described.

In FIGS. 1 and 2, 1.1' is two parallel shafts parallel to each other, and their ends 11, 11' are rotatably supported by bearings 41, 41/.

A plurality of plate-shaped rotary cutters 2, 2...2/, 2/... are attached to the two parallel shafts 1, 1', respectively.
are fitted alternately through the interposition of spacers 3.3...3/, 3/.... As will be described later, the rotation and cutters 2+2' have a relative angle relationship between their tearing blades, etc., so in order to naturally ensure that relationship, the inner diameter of the shaft 1 is made into a hexagonal shape as shown in the figure, and the shafts 1 and 1 are
' is also the fitting part 13.13 of the rotary cutter 2, 2'.
' also has a corresponding hexagonal shape. On the other hand, the spacer 3.3' has an inner diameter larger than the circumscribed circle of the hexagonal part of the shaft so as not to rotate together with the shafts 1, 1', and is attached to the fixed frames 4, 41 with nine rods. 3,3
1 is supported. Thus the two axes 1,1/
The rotary cutters 2 and 2' fitted in the cutters 2 and 2' are arranged so as to mesh with each other alternately.

The rotary cutters 2 and 2' have tearing blades 21 and 21' that protrude in the radial direction at appropriate intervals on the outer periphery, and between adjacent tearing blades 21 and 21 on the outer periphery. ', 21
In between the cutting blades 21 and 21' are provided protrusions 22 and 22' for chip removal that protrude radially outward from the cutting edge diameter of the cutting blades 21 and 21', respectively. The tearing blades 21 and 21' serve to make a horizontal slit in the discarded document before it is shredded into strips in the document input direction.It is preferable that the tip thereof be sharp, and in the case shown in the figure, it is triangular in shape. ing.

In order to further sharpen the tearability, the tip may have a plurality of cusps, for example, at least one V-groove 211 may be provided along the outer periphery of the rotary cutter as shown in FIG. . .

Next, the protrusions 22 , 22 ′ for chip removal are located between the above-mentioned tearing blades 21 , 21 and between 21 ′, 21 ′, and are located radially outward from the circle connecting the blade bases of the tearing blades 21 , 21 ′. It has front slopes 221, 221' that protrude in the direction of the rotary cutters 2, 2' and stand up at an obtuse angle θ with respect to the tangent in the blade base in front of the rotating direction (arrow direction) of the rotary cutters 2, 2'. As will be described later, the protrusions 22, 22' improve the effectiveness of the tearing blades due to their front slopes, and also serve as the cutting blades for the rotary cutters 2, . After the front slopes 221 and 221' begin to push out the chips from the tip, the back surfaces 222 and 22 are used to push out the chips for a certain period of time and make the chip removal effective.
It is illustrated as having a trapezoidal shape such that the contact area (circumferential length) with the tip 2' is large. However, the protrusions 22, 22' may have the shape of a scalene triangle or a semicircular shape as long as it is suitable for the purpose described above.

The rotary cutter has two rotary cutters 2 and 2' fitted on two parallel shafts 1 and 11, and when the tearing blade 21' of one of the rotary cutters 2' starts tearing, the other rotating Front slope 221, 2 of protrusion 22 of cutter 2
The cutting blades 21' are arranged at an angle 14 protruding into the space formed by the cutting blades 21, and preferably, the tip of the cutting blade 21' is set to face the middle part of the front slope 221. The above tearing blade 2
1′, the obtuse angle θ of the front slope 221 mentioned above is:
When forming horizontal slits, the tearing blade guides the paper surface so that it can pierce the paper with low resistance in a state close to perpendicular to the paper surface, and when the chips are removed after shredding. The shape must be comprehensively determined so as to gradually and reliably enter the disengagement state with low resistance.

Next, the shredding operation of the present invention having the above structure will be explained based on FIG. 3.

First, when the document to be shredded is inserted upwardly, the document enters between the rotary cutters 2, 2' which are engaged with each other from the upper introduction portions of the spacers 3, 3'. The document that has entered between the circumferential rotary cutters 2 and 2' is guided by the front slope 221 of the protrusion 22 of the rotary cutter 2, and is separated by the tearing blade 21' of the other rotary cutter 2', as shown in FIG. A slit D1 is formed in the direction. At this time” 2.
21t As mentioned above, guide the document so that the tearing blade 21' penetrates the surface of the document D at an approximately right angle ν and tears it at an obtuse angle with respect to the circumferential direction. DI is formed with extremely low resistance. Next, as the rotary cutters 2 and 2' rotate in mesh with each other, the document is cut into strips in the longitudinal direction, and together with the transverse force direction slit DI, the paper becomes chips D', l)''.The rotary cutters 2
, 2' are disengaged, the tip D// is pushed out by the protrusion 22 of the rotary cutter 2 and detached from the tip. Therefore, the chip 1) begins to be gradually pushed out with low resistance, making sure that the chip 1) is pushed out with low resistance.
Let go and fall.

As described above, in the present invention, tearing blades and protrusions are provided alternately on the rotary cutters that mesh with each other, the front slopes of the protrusions are obtuse angles, and the tearing blades of the other rotary cutter are arranged in the space formed by the front slopes. Since the structure is such that when forming a horizontal slit in a document, the document is pierced with little force to form the horizontal slit, and when the chip is detached, it can be reliably removed, so the chip is inserted between the spacers and accumulated. It does not increase clogging or resistance, improves shredding ability, reduces required power and noise, enables continuous operation for long periods of time, and facilitates maintenance during periodic inspections.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a portion of the rotary cutter of an embodiment of the document shredding machine of the present invention, FIG. 2 is a cross-sectional view thereof, and FIG. Figures 1 and 4 are partial perspective views of a rotary cutter showing the shape of the tearing blade in other embodiments. 1.1'...Rotating shaft 2,2'...Rotating cutter 21.21'...Tearing blade 211,211'...
Groove 22, 22' of tearing blade... Protrusion 221, 22
1'...Front slope 3.3'...Spacer patent applicant Takeshi Hatanaka

Claims (4)

[Claims] (1) It has two rotating shafts that are parallel to each other, and a large number of rotary cutters and spacers that rotate together with the shafts are fitted alternately into each shaft, and the rotary cutters on both shafts are arranged so that they mesh with each other. In the document shredding machine, the rotary cutter has tearing blades that protrude radially outward at appropriate intervals on the outer periphery, and a space between adjacent tearing blades on the outer periphery that is larger than the base diameter of the tearing blade. a chip detachment protrusion that protrudes radially outward; the protrusion has a front slope that rises at an obtuse angle in front of the rotational direction of the rotary cutter; A document shredding machine characterized in that the document shredding machine is arranged so as to penetrate into a space formed by a front slope of a protrusion. (2) The document shredding machine according to claim (1), wherein the tearing blade has a triangular shape. (3) The document shredding machine according to claim (1) or claim (2), wherein the protrusion has a trapezoidal shape. (4) The document specification according to one of claims (1) to (3), characterized in that the tearing blade has a groove in the outer circumferential direction of the rotary cutter. Cutting machine.