US2062952A - Feeding device - Google Patents

Description

Dec.1,1936. A, BWAHLQUST 2,062,952

FEEDING DEVICE Filed July 5l, 1935 2 Sheets-Sheet l Patented Dec. 1, 1936 `UNITED STATES FEEDING DEVICE Albin B. Wahlquist, Chicago, Ill., assigner to The Heyer Corporation, Chicago, Ill., a corporation of Illinois Application July 31, 1935, Serial No. 33,921

'l Claims.

The feeding device of the present invention is designed primarily for the purpose of feeding 'paper sheets singly from a stack to the roller of a duplicating machine, although the latter mechanism constitutes no portion of the present invention, and since the feeding mechanism is adapted for use in connection with machines of various kinds irrespective of the manner in which the paper sheets are -treated or manipulated after delivery by the feeding mechanism.

In the feeding of sheets singly from the top of a stack in such a way asI to bring the leading edge of the paper sheet each time to an exact position for delivery, difcultly has been experienced by reason of the fact that in feeding forward the uppermost sheet there is a tendency to forwardly displace one or more of the underlying sheets so that when such displaced sheets are in turn advanced by the feeding mechanism they will start from a forwardly displaced position, with the result that the leading edge will be advanced to a point beyond the normal line of discharge.

The mechanism of the present invention is designed to overcome the tendency toward such displacement of the underlying sheets by so acting after each feeding stroke as to retract a displaced sheet, so that each sheet of the stack in succession will start from the proper feeding point, with a resulting accuracy in the delivery of the sheets.

Further objects and details of the invention will appear from the description thereof in conjunction with the accompanying drawings, Where- Figure 1 is a side elevation of the feeding mechanism of the present invention as applied to the drum of a rotary duplicating machine;

Figs. 2 and 3 are longitudinal sectional views of the feeding mechanism in different positions of operation;

Fig. 4 is an end view of the feeding mechanism;

Fig. 5 is an enlarged sectional view of one of the feed rollers taken on line 5--5 of Fig. 3;

Figs. -and 'I are enlarged'details of the clutching mechanism for the feed rollers; and

Figs. 8 and 9 are sectional details showing a modified form of cam for actuating the clutching mechanism.

As shown, the feeding mechanism is applied to a duplicating machine comprising a frame I0 and a drum I l which is adapted to be rotated by a handle I3. The duplicating mechanism, however, constitutes no portion of the present invention and need not be described in detail.

The frame of the machine affords a feeding table I4 which is preferably arranged at an incline from front to rear for the support of a stack of paper sheets A, which stack is held in position by side plates I5 and a stop plate IB, which is curved to compensate for the difference in travel of the sheets to the delivery line as the height of the stack diminishes.

The feeding is performed by a pair of corrugated feed rollers I'I, each of which isI carried at the inner end of an arm IB of inverted channel formation, comprising a top web portion I9 and side flanges 20. As shown in Figs. 2 and 3, the web portion near the inner end of each arm is cut away at the point 2| to afford clearance for the roller which is supported between the ends of the inwardly projecting side flanges.

The arms, at their outer or rear ends, are mounted upon a rod 22 which is rigidly secured at its ends between swinging ams 23, the lower ends of which are mounted upon pivots 24 on opposite sides of the frame of the machine. A swinging motion is imparted to the arms 23 by means of links 25, which at their forward ends are adjustably secured to a plate 26 carried by the shaft I2, which plate is provided with an arcuate slot 2l which permits the arms 23 to be adjusted and locked by wing nuts 28 in order to properly time the feeding operations with the action of such devices-grippers or the likeas may be provided for removing the paper sheets after delivery.

Figure l shows in full lines the position occupied by the feed rollers when retracted at the beginning of a feeding movement, and in dotted lines the position of the parts after the roller has been advanced to its limit. In feeding the paper sheets forward, it is desirable to prevent rotation of the feed rollers, so that they will by their weight maintain feeding contact with the surface of the uppermost paper sheet during the period of advancement.

The timing of the machine is such that the feed rollers begin their recession during the interval of withdrawal of the uppermost sheet by the grippers, so that as the feed rollers start hack, they are moving in reverse relation to the paper sheet last delivered, and during this interval it is necessary to unclutch the rollers to afford a rolling contact with the outgoing sheet, but at an intermediate point in the retraction of the rollers they will pass the rear edge of the outgoing sheet and come in contact with the surface of the underlying sheet, and at this point it is necessary to lock the rollers against further rotation in order that they may be utilized as friction elements to draw back the underlying sheet (or sheets) against the stop plate, and thus true up the stack and compensate for previous displacement prior to the next feeding operation.

The mechanism now to be described is designed to lock and unlock the rollers at the proper time to perform the functions above stated.

Each of the rollers |1, which is preferably of rubber or suitable composition, is carried by a cup-shaped mounting 29 provided with an inwardly extending flange 30 the inner edge of which bears upon a pintle 3| provided with a flange 32 against which the inner rim of the flange 39 abuts. The cup 29 surrounds and is journaled upon a partially cylindrical block 33 which is locked to the pintle 3| by a sunk set screw 34 which may be manipulated through an aperture 35 in the wall of the cup. The arrangement is such that the roller mounted upon its cup will journal upon the block 33 and upon the pintle 3|. The outer margin of the cup 29 is shouldered at the point 36 to receive a ring plate 31 which is mounted for rotative movement.

The block 33, as shown in Figs. 6 and 7, is of half cylindrical formation in its upper portion,

`but is cut away on each side of its vertical center to afford a notch 38 leaving a medial projection 39 with a concentrically rounded bearing surface 40, which in conjunction with the upper portion of the block furnishes the journal mounting for the cup 29 with the roller mounted thereon.

The side faces 4| of the medial projection 39 converge toward one another, and in conjunction with the adjacent wall of the cup 29 afford the tapering or wedge-shaped recesses 38 each of which houses a ball 42 backed by a spring 43 the upper end of which is contained within a socket recess 44 in the overhanging upper portion of the block 33.

The two balls 42 act in opposition to one another; that is to say, the right hand ball (as viewed in Figs. 6 and 7) acts to prevent rotation of the roller |1 in a clockwise direction, while the left hand ball acts to prevent rotation in a counter-clockwise direction. In order to disable the right hand ball and permit rotation during the return of the roller after a feeding movement, a pin 45 is provided which extends inwardly beneath the right hand ball and has its outer end entered through and rigidly secured to the ring plate 31 which being rotatable may be adjusted to lift the ball against spring pressure and thus hold the ball within the enlarged upper end of the cavity so that its wedging function will be suspended for the time being, thus permitting a limited clockwise movement of the roller during the period of such adjustment.

The adjusting ring 31 is actuated by a push rod 46 the inner end of which is pivoted upon a pin 41 outwardly extending from the adjusting ring 31. The rear end of the push rod 46 carries a roller 48 which is held against a cam disk 49 by the action of a spring 50. The cam 49 is mounted upon the rod 22 and held in adjusted relation by a thumb screw 5|, and the cam is provided with a flattened surface 52.

From a comparison of Figs. 2 and 3, it will be noted that as the arms 23 swing forwardly, the rod 22 and with it the cam 49 will be moved to cause the roller 48 to roll away from the depressed cam surface and thus impart a counterclockwise movement to the ring plate 31, which slightly lifts the pin 45 and with it the associated ball 42, `so that at the terminus of the forward feeding movement of the roller |1 the roller will be unlocked by the `disablement of one of the balls 42 in preparation for a rolling movement of the feed roller during the beginning of its return movement and while the outgoing paper sheet is advancing in the opposite direction.

As shown in Figs. 2 and 3, the formation of the cam 49 is such as to bring the ring plate 31 back to its initial position to restore both of the wedge balls to locking position toward the terminus of the return movement, but the cam, if desired, may be modified in shape, as shown in Figs. 8 and 9, by limiting the extent of the depression 52a with a resultant change in timing such that the locking of the feed roller on its return will occur during an intermediate interval only and not during the terminal half of said movement.

Operation For convenience and to ensure precision in the feeding of paper sheets, the feed roller arrangement has been duplicated near each end of the rod 22, which brings the feeding pressure to bear near the side margins of the paper, which is ordinarily desirable, although a single roller may be employed in some circumstances.

With the parts in the retracted position shown in Figure 1, the roller (or rollers) Will rest by gravity upon the surface of the uppermost paper sheet. If desired, the rollers may be additionally weighted to insure firmer contact. In this position, the feed roller (or rollers) will be locked against rotation by the action of. the left hand wedge ball 42 (Figs. 6 and 7) irrespective of the adjustment of the right hand ball, so that on the forward or advancing movement of the roller it will maintain frictional contact with the uppermost sheet and carry the same forward to the delivery line. As soon as the sheet is delivered it will be caught and drawn forward by grippers or other appropriate mechanism, and during its discharging movement the feeding mechanism will begin its return movement.

At the terminus of the forward feeding stroke, the cam 49 will have rotated the ring plate 31 suiiiciently to elevate the right hand Wedge ball, with the result that the feed roller will be unlocked and free to roll in reverse arrangement to its movement of recession during a portion of the return movement and until the outgoing uppermost sheet has cleared itself from the feed roller. Thereafter, the depression in the cam 49 will permit a restoration of the ring plate to normal position, with a consequent locking of the right hand wedge ball, so that during a portion of the return movement of the parts, the feed roller will be locked and will thus exert a back feeding pressure on the sheets of. the stack, which tends to true up the stack and compensate for any previous displacement prior to the next forward feeding operation. This results in the feeding of the sheets from a properly adjusted stack at all times and hence insures that the leading edge of each sheet will be fed to the same delivery line, so that the ensuing operations involving additional manipulation of the sheet will be performed with precision and accuracy.

Furthermore, the partial movement of rotation permitted to the roller on each return movement will progressively bring different portions of. the roller surface into operating contact with the sheets so that any wear on the roller surface, due to long continued operation, will be equally distributed around the roller, thereby maintaining its perfect circularity at all times. Of course, the extent of the rolling action can be regulated by the conguration and adjustment of the cam.

it being desirable, however, to avoid a complete rotation (or rotations) in order to constantly bring new portions of the roller surface into operative relation with the stack of sheets.

The feeding mechanism of the present invention is equally adapted to the feeding of thin sheets of. material other than paper, and is adapted for association with any kind of a machine which is designed to operate successively on sheets thus delivered to a common feeding line.

Although the invention has been described with particularity, it is not the intention to limit the same to all of the details shown and described, since modifications can be made without departing from the spirit of the invention.

I claim:

1. In feeding mechanism of the class described, means for holding a stack of sheets in column relation, a feed roller and means for causing the same to reciprocate upon the surface of the stack and in feeding contact with the uppermost sheet, and means actuated by the feeding and return movements of the roller for locking the feed roller against rotation during its forward feeding movements and for unlocking the roller to permit rotation during a portion only of its return movement to insure a back feeding frictio-nal contact with the stack of sheets during a portion of. the return movement, said means including oppositely disposed wedge members interiorly housed and adapted normally to lock the v roller against rotation in either direction, and devices for temporarily moving one of said wedge members from wedging position during a portion of the return movement.

2. In feeding mechanism of the class described, means for holding a stack of sheets in column relation, a feed roller and means for causing the same to reciprocate upon the surface of the stack and. in feeding contact with the uppermost sheet, and means actuated by the feeding and return movements of the roller for locking the feed roller against rotation during its forward feeding movements and for unlocking the roller to permit rotation during a portion only of its return movement to insure a back feeding frictional contact with the stack of sheets during a portion of the return movement, said means including oppositely disposed wedge balls adapted normally to prevent rotation of. the roller in either direction and a pin adapted to lift one of the balls from wedging position, and cam actuated means for adjusting the position of said pin.

3. In feeding mechanism of the class described, means for holding a stack of sheets in column relation, a feed roller and means for causing the same to reciprocate upon the surface of the stack and in feeding contact with the uppermost sheet, and means actuated by the feeding and return movements of the roller for locking the feed roller against rotation during its forward feeding movements and for unlocking the roller to permit rotation during a portion only of its return movement to insure a back feeding frictional contact with the stack of sheets during a portion of the return movement, said means including oppositely disposed wedge balls adapted normally to prevent rotation of the roller in either direction and a pin adapted to lift one of the balls from wedging position, an adjusting ring carrying said pin, a push rod for partially rotating said ring, and a cam properly timed to actuate said push rod.

4. In feeding mechanism of the class described, the combination of a table and guide means for holding a stack of sheets in column relation, including a stop for the rear edges of the stack of sheets, a roller having a frictional surface adapted to bear upon the uppermost sheet of the stack, an arm pivoted at its rear end to a swinging arm and carrying the roller at its free forward end, locking means associated with the roller for preventing rotation thereof during forward feeding movements, and means for disabling said locking means to permit rotation of the roller during the initial portion of the return movement and adapted to restore said locking means to operative relation during an ensuing portion of the return movement to impart back feeding movements to compensate for displacement of sheets in the stack.

5. In feeding mechanism of the class described, the combination of a table and guide means for holding a stack of sheets in colunm relation, including a stop for the rear edges of the stack of sheets, a roller having a frictional surface adapted to bear upon the uppermost sheet of the stack,

, an arm pivoted at its rear end to a swinging arm and carrying the roller at its free forward end, oppositely disposed Wedge balls associated with the roller and normally adapted to prevent rotation of the roller in either direction, and disabling means adapted to displace one of the wedge balls from Wedging relation during the initial portion of the return movement and adapted to restore said ball to Wedging position during an ensuing portion of the return movement to impart back feeding movements to compensate for displacement of sheets in the stack.

6. In feeding mechanism of the class described, the combination of a table and guide means for holding a stack of sheets in column relation, including a stop for the rear edges of the stack of sheets, a roller having a frictional surface adapted to bear upon the uppermost sheet of the stack, an arm pivoted at its rear end to a swinging arm and carrying the roller at its free forward end, oppositely disposed Wedge balls associated with the roller and normally adapted to prevent rotation of the roller in either direction, a pin adapted to lift one of the balls from Wedging position, and cam actuated mechanism associated with the roller operating mechanism for regulating the action of the pin to permit rotation of the roller during a portion of the return movement` 7. In feeding mechanism of the class described, the combination of a table and guide means affording space for the positioning of a stack of sheets in column relation, a feed roller and means for reciprocating said roller upon the uppermost surface of the stack, said means including an arm carrying the roller at its free end, a rod upon Which the opposite end of the arm is pivoted and a swinging arm to which the rod is rigidly secured, a cam rigidly mounted upon said rod, a push rod having its rear end in operative contact with said cam and pivoted at its forward end to a ring plate associated with the roller, a journal block upon which the roller is journalled, said block being notched on opposite sides to aord wedge recesses, a Wedge ball in each of said recesses adapted to normally lock the roller against rotation in either direction, and a pin carried by the ring plate and adapted when rotated by the push rod to lift the associated wedge ball and disable the same to permit limited rotation of the roller during the initial portion of its return movement.

ALBIN B. WAHLQUIST.

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