US2164549A - Duplicating machine - Google Patents

Description

July 4, 1939. P. A. sTEPHr-:NsoN v2,164,549

DUPLICATING IACHINE Filed March 19, 1937 2 Sheets-Sheet 1 July 4, 1939. P. A. sTEPHENsoN 2,164,549

DUPLICATING IACHINE Filed March 19, 1937 Patented July 4, 1939 UNITEDSTATES PATENT oFFlcE DUPLICATIN G MACHINE Paul A. Stephenson, Winnetka, Ill., assignor to A. B. Dick Company, Chicago, Ill., a corpora.

tion of Illinois Application March 19, ll`37, Serial No. 131,766

4 Claims. (Cl. 271-53) My invention relates to duplicating machines the following description taken in connection' and the like and more particularly to sheet feedwith the drawings, which form a part of this ing devices for such machines, and it has for its specification, and in which; principal object to eifect certain improvements Fig. 1 is a viewin perspective of the delivery end in apparatus of this character whereby the feedof a duplicating machine, partially broken away ing of sheets into the printing couple of the mato show the construction, illustrating the applichine may be effected more accurately and withcation of my invention; out slip or damage to the sheets, particularly at Fig. 2 is a side elevation, partially broken away, the higher speeds. 1 of the velocity changing means of my invention; In duplicating machines as now commonly con- Fig. 3 is a sectional view taken substantially structed, sheets are fed either manually or autoon the line 3--3 of Fig. 2; matically from the feed board of the machine'to Fig. 4 is a sectional view taken substantially on a position in which the forward edge of the sheets the line 4 4 of Fig. 3, and is a short distance in front of the crotch, or Fig. 5 is a sectional view taken on the line 5-5 line of contact between the elements of the printof Fig. 3.

ing couple. In this position each sheet is held Referring to the drawings, at I0 is indicated until, the machine having cleared the preceding generally a duplicating machine having the usual sheet, it is engaged by rotary feed segments which side frame members I I, between which are rotatforward it into the crotch at a speed substanably supported a printing cylinder I2 and an tially equal to that of the printing cylinder. I impression roller I3 which form the printing have found that the high velocity with which the couple of the machine. The cylinder I2 is of feed segments engage the stationary sheet frewell-known construction, being provided with a quently causes the sheet to slip with respect to l perforated diaphragm portion I4 through which the face of the segments at the time of contact, ink may be fed from within the cylinder to a causing a delay in the acceleration of the sheet stencil I6 mounted on its outer surface. A drivto machine speed. 'I'his slip becomes more proing pulley I1, rotatably mounted on one of the nounced at higher machine speeds so as to adside frame members II co-axial with the cylinder versely aect registration of the print. Moreover, I2 and operatively connected to the cylinder in the blow which is struck the back of the sheets driving relationship by any suitable means, is acby the segments is frequently of suicient force tuated through a belt I8 from a convenient source to permanently mark the sheet, particularly of power, not shown, which may be an electric where soft or heavy papers areused, and such motor. The other end of the cylinder I2 is supmarking or nicking becomes much worse as the ported by a bearing I9, formed in the hub-2| of machine speed is increased, even to the extent a spur gear 22 which is rotatably mounted on the of tearing the sheets. adjacent side frame. The gear 22 'is connected to One of the objects of my inventionis to provide the cylinder I2 and is driven thereby, having for means whereby a sheet to be fed to the printing this purpose a notch 23 in its hub portion 2I couple of the machine is picked up from rest by adapted for engagement by a suitable dog on the feeding members moving at a relatively low cylinder, not shown. velocity, and is thereafter accelerated to the cor- 'I'he impression roller I3 is joumalled at its ends rect feeding speed, at or slightly above the speed in bearings 26, removably mounted in recesses or of the machine. notches 21 in the ends of parallel arms 28, each Another object of the invention is to provide ,of which arms is pivotally mounted as at 29 on means whereby the feed members are decelerated one of the frame members II. Tension springs just before contact with a sheet to a desirably 3l, connected between the arms 28 and the frame low velocity of contact, and are gradually acceler- II tend to swing these arms upwardly and urge ated after contact has been made to the desired the impression roller toward the cylinder I2 in feeding speed. the usual manner. The machine is provided with A further object of my invention is to provide the usual feed plate 32, over which the sheets of means for varying the speed of the feed segments impression paper, indicated at 33, are forwarded through the previously mentioned cycle of decelto the printing couple, and on which the sheets eration and acceleration without noise or shock are brought to rest in feeding position by the and without the imposition of undesirable stresses usual stop-gate devices indicated at 3l.

4on the parts. After being brought to rest in position on the Other objects of the invention will appear from plate 32, the sheet 33. being fed is picked up and 5 forwarded to the printing couple by suitable sheet feeding members, illustrated as rotary feed segments 35, which are operated in timed relation to the machine and which are provided with the usual arcuate paper engaging surfaces 31 adapted to contact the under side of the sheet. These segments 35 are fixed to and rotate with a shaft 38 which extends across the machine beneath the feed plate 32 and is journalled at its en ds in suitable bearings on the frame members not shown. The segments project upwardly through transversely spaced slots 35 in the feed plate, located between the stop-gates 34, so that the paper engaging surfaces 31 rotate slightly above the level of the plate 32. Cooperating with the segments 35 in the feeding of the sheets are feed rolls 4|, adapted to engage the upper side of each sheet and to press it firmly into engagement with the segment faces 31. The rolls 4| are fixed to a shaft 42, which is journalled at 'its ends in levers 43, pivotally mounted as by hubs 44- on a rock shaft 45. The shaft 45 is journalled in suitable bearings, not shown, carried by the frame members and is provided near its ends adjacent the levers 43 with ilxed arms 41, having projecting lips 48 arranged to engage with abutments or fiat portions 49 on the levers 43. These levers 43 are also provided with extension portions 5| to which are connected springs 52, urgand thereby raise the shaft 42 and rollers 4| out of contact with the plate 32, except when a sheet is to be fed. However, as such actuating and controlling means forms no part of the present invention. it has not been illustrated and further description is unnecessary.

The segment-driving and speed-controlling device of this invention, comprises means for continuously driving the segment shaft 38 from the machine, together with means for periodically decelerating and accelerating said shaft in a fixed cycle with respect to the printing cylinder. As best shown in Fig. 1, the driving means includes a train of gears operatively connecting the cylinder gear 22 to the shaft 38, including a pinion meshing with and driven by the gear 22, a gear 58 meshing with and driven by the pinion 55, a gear 51 co-axial with the gear 55 and meshing with and driving a gear 58 fixed on the shaft 38, and a speed varying connection between gears 55 and 51. The constant speed gear 55 is rigidly secured as by a pin 59. to a shaft 5I, journalled at its ends in bearings 52 formed in bosses 53 on the frame members as shown in Fig. 3. It is formed with an elongated hub portion 54, forming a bearing on which is journalled the variable speed gear 51, co-axial with the gear 55 and spaced therefrom by a washer 55. The hub 54 also carries a locking ring 51, secured thereto as by a set screw 58, which engages the hub of the gear 51 and retains it in axial position.

'Ihe gears 55 and 51 are preferably of the same diameter and number of teeth, and are connected in power transmitting relation by the speed varying means of my invention. This means includes a lever 1I, disposed between the gears 55 and 51 and pivotally connected to the gear 55 at its fulcrum as by a pin 12 mounted1 on the gear. The lever 1| carries a pin 13, 4which projects through an opening 14-formed in the gear 51 and is connected by a link 15 to a pin 11 secured to the body of gear 51. The, lever 1| also carries a pin 18, which projects through an opening 18 formed in the gear 51 and is connected by a spring 8| to a pin 82, carried by the gear 55 and projecting through an opening 83 formed in the gear 51.

Thus it will be evident that gear 51 is driven by the gear 55 through the lever and link connection 1|, 15 to rotate about the common axis of the gears, and that any pivotal movement of the lever 1|4 about its fulcrum 12 during such rotation is imparted to the gear 51 through the link 15, to vary the angular relation of the gear 51 to the gear 55. If the gears are rotating together at a given velocity, movement of the lever 1| transmitted to gear 51 in the direction of rotation accelerates the gear 51; that is, increases its speed and advances it with respect to the gear 55. Conversely, movement transmitted to gear 51 from lever 1| against the direction of rotation decelerates the gear, reducing its speed and retarding it with respect to the gear 55.

To produce the movements of the lever 1| necessary to provide the periodic acceleration and deceleration of the gears 51 and 58, shaft 38 and the feed segments 35, as contemplated by this invention, I provide a fixed cam 84. secured to the frame member in any convenient manner, as by screws 85. Cooperating with the cam 84 is a cam follower 81 comprising a roller 88 mounted on a pin or stud 89 secured to the lever 1|, projecting through an opening 9| in the gear 55. The roller 88 is held in operative contact with the cam 84, as the lever 1| is carried with gear 55 around the cam, by the tension of spring 5I which urges the lever 1| to turn in a radially inward direction about its pivot 12. A supplementary cam 92 is preferably provided for that portion of the cycle in which the pivotal movement of the lever 1|, is most rapid. which occurs just before the segments 35 make contact with the sheet to be fed. Thus during the pick-up period, the cam follower 81 is in contact with both cams 84 and 92 insuring positive movement of the lever 1| without depending on the spring 8|.

'I'he operation of my device will be apparent from the foregoing description. As the leading edge of the segments 35 approach the sheet 33 to be advanced, the cam follower 81 moves on the cam 84 from the high point, indicated on Fig. 5 at A, to the low point indicated at B. The corresponding movement ofthe lever 1| is transferred through the link 15 to the gear 51 being reduced as much as desired, for example one third. Deceleration of the gear 51 is transmitted through gear 58 to the shaft 38, so that at the point of contact with the sheets, the velocity of the segments 35 is relatively low. In this way the segments pick up the sheet and start it forward at a reduced speed. After the sheet has been started, the follower 81 leaves the low portion of the same and rolls on the succeeding portion indicated at C, the profile of which may be a smooth curve of gradually increasing radius, as indicated. As the roller 88 follows this part of the curve, the lever 1| and the link 15 are gradually moved in the direction of movement of the gear 51, resultlng in a gradual acceleration of this gear and with it the gear 58, the shaft 38, vand. the segments 35. In this manner the sheet 33, picked up by the segments at a relatively low velocity, is

thereafter accelerated to, or preferably slightly,

above' the peripheral velocity of the cylinder |2 before its leading edge reaches and makes contact in the crotch of the printing couple.

By this means I am enabled to start the sheet from rest at a velocity suiciently low to obviate slip when the sheet contacts the segments, and to acceleratel it smoothly and uniformly to the de- ;ired feeding speed after contact with the segments has been established. It will be apparent that the absence of slip greatly improves the registration of the prints produced by the machine. and that the absence of shock at the moment of contact prevents damage to the sheets and reduces the noise of operation.

Having thus described my invention, what I claim and desire to secure by Letters Patent, is:

1. In a device adapted to feed sheets from rest, feed members to contact and advance each sheet, driving means for said members including a pair of coaxial adjacent gears, a lever pivotally mounted on one of the gears and disposed be-l tween said gears, a link pivotally connected between the lever and the other gear, and cam means actuating said lever to vary the angular relationship between the gears.

2. In a sheet feeding device, feed members to contact and advance the sheets, a driving gear rotating at constant velocity, a driven gear coaxial with and adjacent to the driving gear and operatively connected to actuate the feed members, lever means carried between and connected to said gears to advance and retard the driven gear with respect to the driving gear, and a cam periodically actuating said lever means.

3. In a sheet feeding device, rotary feed members adapted to start a sheet from rest and to accelerate it to a pre-determined velocity, means to continuously drive said feed members including a constant speed gear anda coaxial variable speedgear, a lever member pivotally mounted on the constant speed gear between said gears. a link pivotally connecting said lever member to the variable speed gear, 'a stationary cam, and a cam follower mounted on said lever member and operated by the cam to actuate said lever.

4. In a sheet feeding device to feed sheets from rest, feed members adapted to contact and advance each sheet, means to continuously drive said feed members including co-axially mounted driving and driven gears, a lever member pivotally mounted on the driving gear, link means connecting the lever member to the driven gear, spring means connecting the lever member to the driving gear, a cam, and a cam follower mounted on the levermember and operated by the cam against the action of said spring means to vary the velocity of the driven gear inA accordance with the speed desired for the feed members throughout the cycle of the device.

PAUL A. STEPHENSON.

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