US2879993A - Paper feeding device - Google Patents

Description

PAPER FEEDING DEVICE Filed May 21 United States Patent O PAPER FEEDING DEVICE Milton V. Scozzafava, Arcadia, and Richard E Busch, La Puente, Calif., assignors to Clary Corporation, San Gabriel, Califl, a corporation of California Application May 21, 1957, Serial No. 660,549

3 Claims. (Cl. 271-2.1)

This invention relates to paper feeding devices for printing machines such as adding-listing machines, cash registers, accounting machines, etc., and has particular reference to feeding devices utilizing pin wheels to positively drive the paper through the machine.

In the above type of feeding devices, the paper generally has a row or rows of perforations along its length in which pins of the pin wheel engage to positively drive the paper.

Such machines generally feed the paper satisfactorily. However, trouble has been encountered in threading new lengths of paper onto the pin wheel so as to initially register the first perforation with a drive pin. This problem is aggravated if the point of insertion of the leading edge of the paper is remote from the pin wheel itself and mustbe suitably guided thereto. I

Although threading under the above conditions may be accomplished by providing a usual narrow paper guiding trough or guide-way leading from the point of entrance to the pin wheel, a constant endwise pressure must be applied to the paper to cause its leading edge to follow one of the pins as the pin wheel is rotated so that a succeeding pin will properly fit in one of the perforations to establish driving relation. Since the paper is relatively weak in compression, it is very difficult to develop a sensitive feel whereby to apply the proper endwise pressure to cause the leading edge to properly follow one of the drive pins. Too much pressure tends to cause the paper to buckle in the guideway whereupon it may jam and thus not feed. Conversely, too little pressure will not cause the leading edge to follow a drive pin and thus the next drive pin will not properly register with a following perforation.

It therefore becomes a principal object of the present invention to thread the leading edge of a length of perforated paper onto the surface of a pin wheel, especially when threaded from a point remote from the pin wheel.

The foregoing object is accomplished by providing a paper guiding trough of a particular shape through which the paper is threaded onto the pin wheel. One wall of the trough is substantially flat. The other wall provides a generally concave paper guiding surface, the two walls terminating in a relatively narrow throat adjacent the pin wheel for guiding the leadingiedge of the paper tangentially onto the pin wheel. When the paper is fed endwise through the throat, the leading edge thereof engages the first pin on the pin wheel. Then, as the paper is further pressed inward, it buckles or bubbles, taking the general shape of the concave contour. of the second Z,879,993 Patented Mar. 31, 1959 ice successive perforation in the paper, even though the paper is held stationary at the point of insertion.

. conjunction with the accompanying drawings, wherein:

' The paper, upon emerging from the container 21, passes Fig. 1 is a sectional view through a paper feeding mechanism embodied in a business machine.

Fig. 2 is a sectional view similar to that of Fig. I, but with parts broken away, illustrating the initial stages of a paper threading operation.

Fig. 3 is a sectional plan view taken along theline 3-3 of Fig. 2;

Referring to the drawing, the machine embodying the present invention comprises spaced side frames, one of which is shown at 11. To the latter are suitably attached auxiliary side frames, one of which is shown at 12. A cross brace 13 is attached at opposite ends thereof to the frames 11 and 12 to maintain them in proper spacial relation.

A platen 14 extends between the side frames 12 and is provided with a shaft 15 rotatably mounted in suitable bearings formed in the frames 12. A pin wheel 16 of the same diameter as the platen and having a plurality of drive pins 17 thereon is suitably attached to one end of the platen.

A means (not shown) is provided to either automatically or manually advance the platen so as to advance the paper thereover into proper relationship with a printing mechanism (also not shown). For details of the manual and automatic platen advancing mechanism, referonce may be had to the copending patent application of Scozzafava and Busch, Serial No. 648,354, filed on March 25, 1957, for Platen Line Spacing Mechanism, now Patent No. 2,843,245.

A paper strip 18 having a row of pin driven perforations 20 along one side thereof (as shown in Fig. 3), is furnished in fanfold or accordion shaped form, several such folds being shown in Fig. 1.

The fanfold paper is mounted in a removable container 21 having front and back Walls 22 and 23, respectively, side walls 19, and a bottom wall 24. The forward wall 23 extends only part way, leaving an opening to permit the paper to be withdrawn forwardly from the interior of the container either beneath a curved lower edge 23a of the wall 23 or over a roller 25 extending between the side walls of the container.

The paper thereafter passes under a second roller 26 and then extends around the combined platen and pin wheel and emerges through a narrow chute comprising two closely spaced parallel guide walls 27 and 28. The

upper wall 27 is curved downwardly around a substan-' tial portion of the periphery of the platen and pin wheel,

but is spaced therefrom sufliciently to allow the paper to pass freely thereunder.

hook 3.0, engageable with studs 31 attached to the side.

frames 12.

into a point of entrance 32 formed partly by the roller 26 and then extends through a peculiarly shaped threading, guide chute before moving over-the pin wheel and platen.

The threading chute comprises a substantially fiat wall 33 and a generally curved second wall 34, the latter being provided at its forward edge with a slot 34a to permit passage of the pins 17.

The wall 33 rests at its upper end on a cross rod 35 extending between the side frames 12. A slot 36 is A slot is provided in the wall, through which the drive pins 17 pass.

formed in the forward edge 37 of the wall 33, and the portion removed to form the slot is bent to underlie the rod 35. The lower end of the wall member 33 is bent to fit over the lateral cross brace 13.

i The walls 33 and 34 are suitably'attached to side plates, one of which is shown at 38, which in turn are suitably attached to the side frames 12 to edge guide the paper strip as it passes through the threading chute.

The upper wall 34 is shaped to form a generally concave paper guiding surface which converges at its upper end with the wall 33 to form a narrow throat 40 extending substantially tangentially toward the periphery of the pin wheel 16 so as to guide the leading edge of the paper thereon. The lower end of the wall member 34 terminates directly adjacent the roller 26.

In threading the paper, the container 21 is removed by unhooking the same from the studs 31. The leading edge of the paper is then passed through the opening or mouth 32 and into the threading chute. Since the paper tends to maintain a relatively straight endwise shape, it may be forced through the chute from a point outside the opening 32, permitting the walls 33 and 34 to generally guide the leading edge through the throat 40 and into engagement with a pin of the pin wheel positioned adjacent the throat. Further inward pressure against the paper causes it to bow as it assumes substantially the form shown in Fig. 2. It will be seen that the shape of the wall 34 is such that the paper may bow to a limited extent only and will not tend to buckle back upon itself and thereby lose its endwise stiffness. Also, when completely bowed, the paper will form a smooth curve wherein the leading edge portion extends substantially tangentially therefrom and through the throat 40.

When so inserted, the outer portion of the paper may be held stationary while the leading edge thereof exerts a light endwise pressure against the nearest drive pin due to its inherent resiliency. The paper thus tends to staighten out even though it has not been inserted so far as to completely bow into the position shown in Fig. 2. Accordingly, when the platen and pin wheel are rotated clockwise, the leading edge of the paper will follow the engaged drive pin until the next pin engages in the next perforation whereupon a positive driving relation is established. The container is then replaced, permitting the paper to follow the path shown in Fig. l.

The leading edge 41 of the paper is preferably formed, as shown in Fig. 3, with a partial pin perforation 42 regularly spaced from the first whole perforation a and arranged to engage the surface of the nearest drive pin 17 extending from the pin wheel.

Although we have described our invention in detail in its preferred form and have therefore utilized certain specific terms and languages herein, it is to be understood that the present disclosure is illustrative rather than restrictive and that changes and modifications may be made without departing from the spirit or scope of the claims appended hereto. For example, the wall member 33 may be formed to present a slightly convex paper guiding surface to assist in causing the paper within the threading chute to assume its bowed shape.

Having thus described the invention, what we desire to secure by United States Letters Patent is:

1. A paper feeding device for a printing machine or the like in which a paper having regularly spaced pin holes therealong is fed by a pin wheel engageable in said holes, comprising first and second spaced walls forming a threading chute, said walls terminating in a guide throat extending adjacent the periphery of said pin wheel, said walls forming an entrance mouth at a point remote from said throat, said second wall presenting a generally concave paper guiding surface terminating in a portion extending substantially tangent to the periphery of said pin wheel, said walls being effective to guide said paper into an endwise bowed shape when forced into said chute whereby said paper will tend to straighten out and thereby exert a yielding force to maintain its leading edge against a pin on said pin wheel during rotation of said pin wheel, said first wall presenting a guiding surface effective to prevent said paper from bowing away from said second wall, the length of said concave paper guiding surface approaching a distance equal to the straight line distance between said mouth and said throat plus the spacing between adjacent ones of the pins on said pin wheel.

2. A paper threading device for a printing machine or the like in which a paper having regularly spaced pin holes therealong is fed by a pin wheel engageable in said holes, comprising first and second spaced walls forming a threading chute, said walls terminating adjacent said pin wheel in a guide throat, said walls forming an entrance mouth at a point remote from said pin wheel, said first wall presenting a paper guiding surface located substantially in a fiat plane, said second wall terminating adjacent said pin wheel in a portion extending substantially tangent to the periphery of said pin wheel and said second wall presenting a substantially concave paper guiding surface effective to guide said paper into an endwise bowed shape when forced into said chute whereby said paper will tend to straighten out and thereby exert a yieldable force to maintain its leading edge against a pin on said pin wheel during rotation of said pin wheel, the length of said concave paper guiding surface approaching a distance equal to the straight line distance between said mouth and said throat plus the spacing between adjacent ones of the pins on said pin wheel.

3. In a paper threading device for a printing machine or the like in which a paper having regularly spaced pin holes therealong is fed by a pin wheel engageable in said holes, comprising first and second spaced walls forming a threading chute, said walls forming an entrance mouth at a point remote from said pin wheel, said first wall terminating adjacent said pin wheel and presenting a paper guiding surface located substantially in a flat plane, said second wall terminating adjacent said pin wheel and presenting a substantially concave paper guiding surface effective to guide said paper into an endwise bowed shape when forced into said chute whereby said paper will tend to straighten out and thereby exert a yielding force to maintain its leading edge against a pin on said pin wheel during rotation of said pin wheel, the portion of said second wall which terminates adjacent said pin wheel extending substantially tangent to the periphery of said pin wheel, the length of said concave paper guiding surface approaching a distance equal to the straight line distance between said mouth and said end of said second wall adjacent said pin wheel plus the splaciiig between adjacent ones of the pins on said pin w ee References Cited in the file of this patent UNITED STATES PATENTS 1,882,014 Howell Oct. 11, 1932 FOREIGN PATENTS 893,981 France Mar. 6, 1944

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