US2228553A

US2228553A - Safety paper guard for paper cutters

Info

Publication number: US2228553A
Application number: US361987A
Authority: US
Inventors: Barney Freeman
Original assignee: Challenge Machinery Co
Current assignee: Challenge Machinery Co
Priority date: 1940-10-21
Filing date: 1940-10-21
Publication date: 1941-01-14
Anticipated expiration: 1958-01-14

Description

Jan. 14, 1941. F, BA N Y 2,228,553

SAFETY PAPER GUARD FOR PAPER CUTTERS Filed Oct. 21, 1940 I l I1 \hvexd'or a j hheman 'B g1neb MMX I. ,3 we W Patented Jan. 14, 1941 UNITED STATES PATENT OFFICE SAFETY PAPIR GUARD FOR PAPER UTT'ER Application October 21, 1940, Serial No. 361,987

6 Claims.

This invention relates to paper cutters and more particularly to a safety paper guard for paper cutters.

This invention is designed to be an improvement over devices such as shown in the patent to James L. Lee, No. 732,754, patented July 7, 1903. In paper cutters of this character the knife and knife bar move vertically and longitudinally of the paper cutter to perform a shear cut. This longitudinal movement of the knife and knife bar has a tendency to force the strips of paper, which are cutfrom the paper stock, into the space between the vertical guides for the knife and knife bar. The, paper strips in this opening sometimes vcause clogging and unnecessary delay in the cutting operation. Occasionally the paper strips cause damage to the machine when deposited between the guide members. It has also been found that the operator of the machine will sometimes forgetfully put one of his fingers or his hand in this opening between the guide members below the knife and knife bar.

One object of this invention is to provide a means for filling this space between the guide members below the knife and knife bar to prevent the scrap strips of paper from being deposited into this opening and also to prevent the operator from accidentally putting his finger or hand into this opening.

Another object of this invention is to provide means whereby the paper guide may be caused to be inoperative without removing any of the parts of the machine, it being necessary simply to move the guard to its lowermost position to be- 35 come inoperative.

Another object of the invention is to provide a paper guard in which the operation of the guard is not caused by means of springs but by a weighted arm which will not easily get out of order.

The invention provides various novel features of construction and arrangement as are hereinafter more fully described and particularly pointed out.

Fig. 1 is a fragmentary front elevation of a paper cutter having the paper guard embodying this invention applied thereto.

Fig. 2 is a vertical section of a portion of the machine having the paper guard applied there- Fig. 3 is an end elevation of the portion of the machine shown in Fig. 2.

Fig. 4 is a vertical sectional view along line 4-4 in Fig. 2, and

Fig. 5 is a horizontal section taken along line 55 of Fig. 3.

Like numerals refer to like parts in the various views of the drawing.

The paper cutter to which the safety paper guard is applied is of conventional form having a base I, the work table 2, an upper knife supporting structure 3 which is supported by vertical spaced parallel knife guides 4 and 4a. Other conventional parts of the paper cutter include a knife bar 5 to which is attached a knife 6. This knife bar is attached to the supporting structure 3 by means of the pivoted links 1. An operating link 8 is pivotally connected to the knife bar and provided with suitable operating mechanism so that the knife bar may be operated to cut the paper.

With the knife bar mounted on the links 1, on operation of the knife bar the knife bar and knife will move in a rotative motion around the pivots of the links I causing them to move vertically and also longitudinally. When paper to be cut is located in the machine and the knife and knife bar is operated, the longitudinal motion of the knife bar tends to move the scrap strips of paper to the left of the machine as shown in Fig. 1 and toward the space between the knife guides 4.

This space between the knife guides 4 is provided with a paper guard to prevent the scrap strips of paper from being deposited between them. The opposite faces of the knife guides 4 are grooved as at H to receive the tongues [2 formed on the vertical edges of the sliding plate I3. This plate 13 is recessed at 14 at its outer side and has a plain face at its inner side. This inner side of the plate l3 lies flush with the inner faces of the knife guides 4 to present a continuous surface between the knife guides. The upper edge of the plate I3 is formed to substantially the same con-tour as the lower faces of the knife and knife bar. This upper edge of the plate I3 is provided with two spaced bearing members 15 between which there is rotatably mounted the beveled roller Hi. This beveled roller contacts the lower sides of the knife bar 5 while the paper cutter is in normal operation. A boss I! is formed at the lower edge of the plate l3 into whichis screwed the rod t8 which had an enlarged head l9.

Two studs 20 are screwed into an overhanging portion 2| of the base 2. A supporting bracket 22 has a central horizontal portion 23 and outward horizontally extending ears 24 through which screws pass into the studs to attach the supporting bracket to the paper cutter. An opening is formed through the base of the .paper cutter, and the supporting bracket 22 has downwardly and inwardly extending parallel legs 26 which extend through this opening in the base to a location within the confines of the base. A web 27 extends between the two legs 26. A lever 28 is pivoted between its ends to the inner ends of the legs 26 and is provided at its inner end with a weight 3| and at its outer end with an arcuate faced head 29 which engages the enlarged head I9 of the rod l8 and thrusts the plate [3 upward so that the roller [6 is constantly in engagement with the lower edge of the knife bar in normal operation.

The plate i3 has the ledge 32 formed integrally therewith adjacent its lower edge. A hookshaped spring 33 is screwed to the upper face of the horizontal portion 2-3 of the bracket 22. When it becomes necessary during the use of the machine to remove the knife therefrom and at other occasions when it is desirable to move this paper guard plate [3 out of the way, the plate may be lowered until the ledge 32 moves under the hooked spring 33 so that the plate will be held in its lowermost position. The plate I3 is held in this position until released by an outward pull on the spring 33. As soon as the plate is released it is moved to its upper position by means of the weighted lever 28.

In the operation of the machine a stack of paper is located on the work table 2 and held there by a conventional means. The links 8 are operated to move the knife and knife bar rotatably on the links 1 which movement cuts off strips of paper from the edge of the stack of paper. With the paper guard located between the knife supports these scrap strips of paper cannot be deposited between the knife guides. On downward movement of the knife and knife bar the plate !3 moves downwardly therewith until the knife and knife bar have reached their lowermost position. As the knife and knife bar are raised the plate l3 will follow the upward movement closely so that the opening between the knife guides is always closed.

It will be noted from the foregoing description that means are provided for preventing the scrap strips of paper from moving into the space between the knife guides and also for preventing the operator from accidentally putting his hands into that space. It will also be apparent that the guard is easily and effectively moved to an out of the way or inoperative position and is also easily made operative. It will be seen that by the use of a weighted arm the device will not easily get out of order. The roller I5 engaging the knife bar prevents engagement of the knife proper with the guard.

Having thus described my invention, the particular construction which I claim as new is defined in the appended claims and is to be con sidered comprehensive of all forms of structure coming within their scope.

I claim:

1. The combination with a paper cutter having a frame, spaced guide members, and a knife and knife bar movable between said guide members, of a paper guard comprising; a plate slidably mounted between said guides, said plate having a portion contacting said knife bar, yieldable means for holding said contacting portion in contact with said knife bar.

2. The elements in combination defined in claim 1 in which said yielding means comprises a weighted lever pivoted to said frame and actuating said slidable plate.

3. The elements in combination defined in claim 1 in which said sliding plate moves vertically to contact said knife bar, combined with releasable means to hold said sliding plate in lowered position.

4.. The elements in combination defined in claim 1 in which the inner face of said slidable plate is flush with the inner face of said guide members.

5. The elements in combination defined in claim 1 in which the knife bar has a beveled face and said contacting portion of said slidable plate comprises a beveled roller to contact the beveled face of the knife bar.

6. The combination with a paper cutter having a frame, spaced guide members, and a knife and knife bar diagonally movable between said guide bars, of a paper guard comprising; a vertically slidable plate extending between and guided by said guide members, anti-friction means on said slidable plate contacting the under side of said knife bar and holding said sliding plate out of engagement with said knife and yieldable means for maintaining said anti-friction means in contact with said knife bar.

FREEMAN BARNEY.