US2005450A

US2005450A - Paper feeding mechanism

Info

Publication number: US2005450A
Application number: US701616A
Authority: US
Inventors: Raymond G Bower
Original assignee: Burroughs Adding Machine Co
Current assignee: Unisys Corp
Priority date: 1933-12-09
Filing date: 1933-12-09
Publication date: 1935-06-18
Anticipated expiration: 1952-06-18

Description

Qgfi "13, 1935- R. G. BOWER 7 2,005,450

PAPER FEEDING MECHANISM Filed Dec. 9, 1935 v 2 Sheets-Sheet 1 IIEIVENTOR Egg/220710, 6.50am

ATTORNEYS June-1s, 1935 R. G. BOWER PAPER FEEDING: MECHANISM 2 sheets-shecct 2 Filed Dec. 9, 1933 INVENTOR ayawnd 6 Bower I ATTORNEYS Patented June 18, 1 935 UNITED STATES PATENT OFFICE,

PAPER FEEDING MECHANISM Raymond G. Bower, Detroit; Mich., assignor to Burroughs Adding Machine Company, Detroit, I Mich., a corporation of Michigan Application December 9, 1933,Serial No. 701,6l6

9 Claims. (01. 197-138) This invention relates to paper feeding mecha- A single rear feedroll'3ll is shown in the presnism for typewriters, calculating machines and ent embodiment, but several rear feed rolls may the like, particularly to the feed roll and paper be used if desired. The rear r011 30 is carried bya pan features of such machines. x a shaft 3| journaled in arms 32 pivoted on the The general object of the invention isto proshaft 23. These arms are urged clockwise about 5 vide improved paper feeding mechanism for their pivots 23 bysprings 33 connected to the typewriters, calculating machinesand the like. arms and to brackets 34 on the back plate Amore particular object is to provide'improved The tension of springs 33 may be adjusted by feed roll mounting and feed roll releasing means means of screws 35.

for such m hin t From the description given, it will be clear that 10 A further object is to provide 'ani'mprov'ed the front and the rear feed rolls are urged topaper pan arrangement and mounting for such Wa d the p y Separate sp ng means so machines. that the tension of the rolls may be varied inde- Still another object is to provide improved Pendentlyi This enables the t ess With means'for automatically closing the gap between which the rear roll grips the paper to be varied 15 ,the feed roll and the paper pan when the feed roll with resp to t tightness th wh h the and platen are e t 7 front rolls grip the paper and it has been found Other and more particular objectswill hereinhat this enables a better feeding action to be k after appear. obtained. An embodiment of the invention is shown in Feed roll release means 20 the accompanying drawings, in which;

Figure 1 is a perspective view of the invention 12 1 igg j g parts spread to illustrate them while a paper or papers are being passed about the platen after which the feed rolls can be re- Fig. 2 is a sectional elevation of the invention leased for engagement with the papers to h 01 d 25 with the feed rolls in engagement with the platen;

them in feeding relation to the platen. Fig. 3 is a view similar to Fig. 2 with the feed rolls out of Contact with the platen; and The feed rolls are released by means of a feed roll release lever 40 having a thumb piece 41, 5 3 f EZZ of prtlon of the feed said leverbeing journaled on a shaft 42. The 30 The invention is Shown applied tn the travek lower end of the lever has a toothed sector 43 whose teeth mesh with teeth on a sector 44 fixed mg paper carriage of a typewriter, which carriage comprises side plates llland ll joined by a cross to a feed 1011 lelease shaft Journaled at one late H and at its other end in piece 52 and a back plate l3. A rotatable platen end in the end p R P is suitably journaled in the cross plates In g j fg hand bracket 24 f m t 5 and The release shaft 45 has a plurality of notches 46 and 4'! in it corresponding in number to the Associated with the platen P are front and rear number of

levers

22 and 32 which carry the front feed rolls adapted to cooperate with the platen and rear feed rolls respectively. These notches to hold papers thereagainst and to cause the are shown in Fig. 4 where it will be seen that papers to be line spaced or fed as the platen is there is a separate notch for the rear and front rotated. feed roll carrying levers, the notches 46 being The front feed rolls 20 are carried by a shaft for the front feed roll levers and the notches 41 2i supported on arms 22 pivoted on a shaft 23 for the rear feed roll levers. These notches form that is fixed in end plates 24, shown in Fig. 1, actuating camsurfaces for the feed roll levers said end plates being fixed to the carriage rail and the periphery of the shaft 45 forms a dwell E2. The arms 22 have downwardly extending portion of the cams. L-shaped arms 25 (Fig. 1), and, connected be- The front feed roll supporting levers 22 have :tween the ends of these arms and studs 26 on the downwardly projecting arms 50 provided with stationary brackets 24, are springs 21 whose 'tensurfaces 5| adapted to engage in the slots 46 of 50 sion is adjustable by means of screws 28. These shaft 45. springs exert a tension on the arms 22 tending to The lower ends of the rear feed roll supporting urge them counterclockwise about their pivots 23 levers 32 have cam ends 52 adapted to engag (Fig. 2) so that the front rolls 20 are urged toin the slots 41. 55 ward the platen P. When the feed rolls are in enzagement with 55 The feed rolls may be moved out of engagement with the platen and held in this position Feed roll mounting the platen, the parts occupy the position illustrated in Fig. 2 where the cam edges 5| and 52 are in the slots 46 and 41, respectively.

When the feed roll release lever 40 is pulled from the position of Fig. 2 to that of Fig. 3, the shaft 45 is turned to the position of Fig. 3 where, it is to be noted, the cam edges 5| and 52 of the

levers

22 and 32 are not only out of the slots 46 and 41, but a considerable portion. of the periphery of the shaft 45 is turned under the ends or edges of these levers. Two functions are accomplished by this constructionv and arrangement of parts, with the following advantages.

In the first place, the feed roll release shaft,

45 is relieved of torsional strain when the feed rolls are in released position because, at that time, the edges 5| and 52 are bearing against the periphery of the shaft 45 without exerting any tendency to turn it.

The second functionand advantage is that it is not necessary to provide a detent to hold the feed roll release lever'in its released position. In constructions in which the active cam surfaces remain in engagement with the feed roll supporting levers,- some sort of detent' has to be providedto hold the levers out of engagement with the platen. But, with the construction above described, not only is the release shaft relieved of torsional strain, but the feed roll release lever need not be provided with a detent.

Paper pan mounting Positioned beneath the platen is a paper pan time the feed rolls and platen areseparated.

.This pan is in the form ,of an arcuate metal sheet adaptedto fit the under surface of the platen. Toward its forward edge, the pan is provided with downwardly extending lugs or projections-M having L-shaped slots 62 in them by means of which the projections may be fitted over the shaft 2! which acts as a guide for the pan. Near its rear edge the pan may rest on the arms 32 although it does not normally rest on such arms owing to the fact that the pan is urged toward the platen by springs 63 near both ends, said springs surrounding a shaft 23 in each of the two brackets 24 and each having one of its ends bearing against the underside of the pan 60 andthe other end bearing against the shaft 45. The springs cause the pan to lightly engage the platen, the pan being free of the feed rolls and not being disturbed by movement of these rolls into and out of engagement with the platen. The rear end of the pan is limited in its upward movement by engagement with the back plate l3, as shown in Fig. 2,- so that there is always a slight space between the pan and the platen for the reception of a paper or papers that may be inserted.

The front or forward portion of the pan is urged into engagement with the platen at all times by the springs 63. This engagement is light so that it does not interfere with the progress of paper that maybe inserted from the rear but is heavy enough to lightly hold the paper after it has been inserted.

When the feed rolls 2!) and 30 are moved away from the platen, the paper pan remains in the same position as it did while the rolls were engaging the platen, as will be clear from the illustration of the parts in Figs. 2 and 3. When the feed rolls have been released, a paper may be inserted from the rear and this paper will be held in contact with the platen by the relatively light urge of the front edge of the paper pan. The paper is thus held while the feed rolls are moved toward the platen, with the result that the papers are gripped accurately instead of being moved as they might be if the paper pan moved to and from the platen.

Another advantage of the construction is that considerable friction between the paperpan and. the platen is removed so that the papers can slide forward easily. If the pan were to grip the platen over its entire lower surface, a snubbing action would result and the paper would have a tendency to cling or stick to the platen whichwould make it hard to move to position.

If the platen is removed from the carriage for any reason, the paper pan 60 remains in position even though it is urged upward by the spring 63. 5 This is due to the fact that the slots 62 in the projections 6| are L-shaped and the bottom of the slots catch on the shaft 2| and, the back plate I3 block the rear end of the pan.

Means for automatically closing the gap between the feed roll and the paper pan when the feed roll and platen are separated As shown in Figs. 1 and 2, the rear feed roll 30 is adapted to engage the platen through a slot or opening 10 in the paper pan. It is necessary to have the feed roll spaced a substantial distance from the edge of this opening in order that the feed roll may rotate freely while it is in engagement with the platen. When this is done an opening or gap H exists between the feed roll and the edge of the opening in the pan.

This gap has been considered a necessary evil in many paper feeding constructions. The difliculty with the gap is that there is a tendency for papers, particularly if they are stiff, to catch in the gap when they are being fed under the 0 gap between it and the edge of the opening in the pan will tend to become larger and more susceptible to stopping papers.

To avoid the difiiculty, means has been provided for automatically closing this opening or gap when the rear feed and platen are separated. In the embodiment shown, this consists in mounting the rear feed roll shaft in inclined slots 80 in the arms 32. As the feed roll is moved away from the platen, the weight of the roll is enough to cause it to move downwardly and forwardly in the slots 80 from the position of Fig. 2 to that of Fig. 3 where it will be observed that the feed roll closes the gap so that the papers cannot catch in the opening.

As the feed rolls are moved away from the platen the feed roll shaft 3| moves behind shoulders 8| on the brackets 24 (Figs. 3 and 1) which prevent the feed rolls being pushed up in the slots 8|] when a stiff card is inserted.

When the feed roll is moved toward the platen again, the influence of the springs 33 is such as to cause the rolls to roll upwardly so that the supporting shaft 3| moves from the position of Fig. 3 to that of Fig. 2 where the feed roll is free to rotate without interference from the pan. This movement of the feed roll also tends to smooth out the papers which are held by the front edge of the paper pan and the front feed rolls.

While the above construction has been shown with only a single rear feed roll, it will be clear that the same construction could be used with a plurality of rear rolls or with front rolls if such construction were designed for a set of front rolls. Likewise, while, in the embodiment i1- lustrated, the feed roll is moved away from the platen to provide a throat or opening for receipt of papers, the construction would operate if the platen were moved away from the feed roll to provide this opening.

It will be understood that the construction shown is for purposes of illustration only and that variations may be made in it without departing from the spirit and scope of the invention as defined by the appended claims.

I claim:

1. In a machine of the class described, a platen, front and rear feed rolls movable into and out of engagement with said platen, means supporting said rolls, a paper pan guidingly interlocked with said roll supporting means and mounted so as not to be affected by the movement of said rolls into and out of engagement with said platen, means for urging said pan intoengagement with said platen, and means for limiting the movement of the rear portion of said pan toward said platen whereby a slight space remains between said platen and the rear of said pan while the front edge of said pan engages said platen whereby papers may be easily fed under said platen from the rear but will be lightly gripped at the front of said platen.

2. In a machine of the class described, a platen, feed rolls movable into and out of engagement with said platen, a paper pan mounted so as not to be affected by the movement of said rolls into and out of engagement with said platen, means urging said pan upward toward said platen, and means operable to limit the upward movement of said pan when said platen is removed, said means being also operable to enable the pan to be quickly removed when desired.

3. In a machine of the class described, a platen, a paper pan cooperating with said platen, a feed roll adapted to engage said platen through openings in said paper pan whereby a gap is left between said roll and said pan, means for separating said feed roll and said platen, and means automatically closing the gap between said feed roll and pan as said feed roll and platen are separated.

4. In a machine of the class described, a platen, a paper pan cooperating with said platen, a feed roll adapted to engage said platen through openings in said paper pan whereby a gap is left between said roll and said pan, means for separating said feed roll and said platen, means automatically closing the gap between said feed roll and pan as said feed roll and platen are separated, and means for holding said gapclosing means .in gap-closing position while said feed rolls and platen are separated.

5. In a machine of the class described, a platen. a paper pan cooperating with said platen, a feed roll adapted to engage said platen through an opening in said paper pan so that a gap remains between said roll and said pan, means for separating said feed roll and said platen without moving said paper pan whereby the tendency is for said gap to become more effective in catching papers that may be inserted between said feed roll and platen, and means automatically closing said gap as said feed roll and'platen are separated. v

6. In a machine of the class described, a platen, a paper pan cooperating with said platen, a feed roll adapted to engage said platen through an opening in said paper pan so that a gap exists between said roll and pan, means for separating said feed roll and platen, and supporting means for said feed roll operable, as said roll and platen are separated, to cause said roll to automatically close said gap.

'7. In a machine of the class described, a platen, a paper pan cooperating with said platen, a feed roll adapted to engage said platen through an opening in said pan so that a gap is formed between said roll and pan, means for separating said feed roll and platen, and arms carrying said feed roll having inclined slots in which said feed roll is mounted, so that, as said feed roll and platen are separated, said feed roll will move in said inclined slots to close said gap.

8. In a machine of the class described, a platen, a paper pan cooperating with said platen, a feed roll adapted to engage said platen through an opening in said pan so that a gap is formed between said roll and pan, means for separating said feed roll and platen, arms carrying said feed roll having inclined slots in which said feed roll is mounted, so that, as said feed roll and platen are separated, said feed roll will move in said inclined slots to close said gap, and means for holding said roll in gap closing position while said roll and platen are separated.

9. In a machine of the class described, a platen, a floating paper pan urged into engagement with said platen so as to loosely engage said platen at the front and to be slightly spaced therefrom at the rear, whereby papers may be easily inserted under said platen from the rear and will be loosely held at the front, front and rear feed rolls adapted to be moved into and out of engagement with said platen, and means for causing said rear feed roll, as it engages said platen at the rear, to move upward slightly while the paper is held at the front by said paper pan and said front feed rolls.

RAYMOND G. BOWER.