US 3921920 A
Machine for destroying documents, of the kind which contains two parallel shafts driving cutting discs or cutting tools engaging one another, characterized in that there is used two pairs of shafts equipped with cutting tools, said pairs of shafts being disposed one above the other, and a means is introduced between them to pivot the shreds cut out by the upper cutting tools in such a way that said shreds will fall in a substantially horizontal direction of the lower cutting tools.
Claims available in
Description (OCR text may contain errors)
United States Patent 11 1 Brocard 1 1 Nov. 25, 1975 MACHINE FOR DESTROYING DOCUMENTS l-luguette Brocard, 14, rue de lOdeon, 75006 Paris, France Filed: Apr. 18, 1974 Appl. No.: 461,940
 Foreign Application Priority Data Apr 27, 1973 France 73.15282 U.S. Cl 241/159; 241/236 Int. Cl. B02C 13/20 Field of Search 241/101.4, 159, 236;
References Cited UNITED STATES PATENTS 3/1914 Guettler 241/236 X 1,340,225 5/1920 Howard 83/35 X 3.630,46O 12/1971 Goldhammer 241/236 3,713,358 1/1973 Honeycutt et al. 83/35 3,727,850 4/1973 Krigbaum 1. 241/159 Primary ExaminerGranvi1le Y. Custer, Jr. Attorney, Agent, or Firm--Ul1e C. Linton  ABSTRACT Machine for destroying documents, of the kind which contains two parallel shafts driving cutting discs or cutting tools engaging one another, characterized in that there is used two pairs of shafts equipped with cutting tools, said pairs of shafts being disposed one above the other, and a means is introduced between them to pivot the shreds cut out by the upper cutting tools in such a way that said shreds will fall in a substantially horizontal direction of the lower cutting tools.
2 Claims, 2 Drawing Figures U.S. Patent v Nov. 25, 1975 Sheet 1 Of2 3,921,920
. I 4 a x F U.S. Patent Nov.25", 1975 Sheet2of2 3,921,920
MACHINE FOR DESTROYING DOCUMENTS The present invention relates to a machine for destroying documents, of the type which permits cutting documents into shreds.
Such machines are generally constituted by two series of cutting discs, or cutting tools, mounted on a shaft driven by a mechanical means with the discs in one series engaging between the discs of the other series, and each disc rotating between guides integral with the frame of the machine.
In order that the document, which is to be cut into shreds, may not be reconstituted, it is necessary that said shreds be very narrow, and this makes it necessary to use very thin cutting tools, which are therefore very fragile, and not very efficient.
The present invention relates to a machine which, aside from the fact that it can have high efficiency, guarantees the total destruction of the document, and it is remarkable in that it contains two shafts provided with cutting tools, and below then, a second, indentical device, and a means being provided between these two devices so that the shreds produced by the upper device will pivot by substantially 90 in such a way as to be placed horizontally, before falling onto the cutting tools on the lower device.
In this way there is obtained, at the outlet from the machine, very irregular and completely unreadable particles.
The invention will be better understood, on reading the description which follows, made in reference to the attached drawings by way of indicative example only, in which:
FIG. 1 is a diagrammatic sectional view of the machine, made through a vertical plane perpendicular to the plane of the cutters, and,
FIG. 2 is a diagrammatic partial side view of FIG. 1.
Referring to the drawing, the machine is composed of two parallel means, and on which are keyed cutting tools 3 and 4 with cutters 3 engaging between cutters 4.
In a known fashion, crossbraces 5, held by rods 6, are inserted between the cutters.
The above device as a whole constitutes an ordinary machine for cutting documents into shreds or strips.
According to the present invention, this first device is disposed in a frame, shown at 7, above a similar device containing two shafts 8 and 9. cutters 10-11, and crossbraces 12 held by rods 13.
Shafts l, 2, 8 and 9 rotate according to arrows F and F2.
Between these two devices there is inserted a means which permits bedding the shreds produced by the upper device. in such a way that they will be disposed substantially horizontally when they fall onto cutters 10 and 11.
In this way, the shreds are cut again and reduced to the state of completely illegible particles.
The said means can be constituted by a rotary spiral screw 14. It should be noted that the axis of the screw is offset with respect to the vertical plane of symmetry X-Y of the apparatus.
Assuming that screw 14 is turning according to arrow F (FIG. 2), it can be seen that when thread S meets the lower end of a strap L, which falls according to arrow F the latter is displaced according to arrow F and will occupy the position L shown in broken lines. When the strap L escapes from cutters 3-4, nothing prevents it from rocking and it will now occupy, as it falls, position L that is to say, one according to which the strap will extend parallel to the axes of cutters In addition, in order to prevent wadding, the speed of rotation of screw 14 is higher than that of shafts 1 and 2, and the speed of rotation of shafts 8 and 9 is higher than that of said screw.
Since the documents are cut twice, it is not necessary that the shreds be very thin, and therefore we can use relatively thick, hence strong, cutting tools, and obtain high efficiency.
1. Machine for destroying documents comprising, in combination, a first device constituted by two driven shafts to be driven in rotation in opposite directions to one another, cutters being mounted on said shafts, the cutters on one of said shafts interlocking between the cutters on the other of said shafts, a second device similar to and disposed below said first device, and a rotary driven spiral screw disposed between said two devices with the axis of said screw being parallel to those of said shafts of said two devices.
2. Machine for destroying documents according to claim 1, in which the axis of said screw is offset with respect to the vertical plane of the machine.