US3074608A

US3074608A - Adjustable feed mechanism

Info

Publication number: US3074608A
Authority: US
Inventors: Joachim H Ohme
Original assignee: Western Electric Co Inc
Current assignee: AT&T Corp
Priority date: 1960-08-19
Filing date: 1960-08-19
Publication date: 1963-01-22
Anticipated expiration: 1980-01-22

Description

Jan. 22, 1963 J. H. OHME 3,

ADJUSTABLE FEED MECHANISM Filed Aug. 19. 1960 2 Sheets-Sheet 1 Iii 0) NVEIN Tut-7 .J. H. UHITTE' Jan. 22, 1963 J. H. OHME 3,0

ADJUSTABLE FEED MECHANISM Filed Aug. 19. 1960 2 Sheets-Sheet 2 I HTTURNE'Q United States Patent corporation of New York Filed Aug. 19, 1960, Ser. No. 50,743 6 Claims. (1. 226-141) This invention relates to feeding mechanisms and particularly to an improved adjustable mechanism for controlling the feed of strip stock into a press.

In the operation of standard impression machines, stamping machines and like presses requiring an intermittent feed of strip stock, various adjustable mechanisms have been devised for controlling the amount of strip feed. However, most of these machines are either rotatably or arcuately driven, such as the type shown in Patent 2,011,736 to M. A. Suarez in which the feed is regulated by connecting one end of a rack along an arcuately driven member pivotally mounted to the machine.

The feed is proportional to the distance between the relative position of the rack end and the pivotal connection, the feed being increased as the rack end is moved away from the pivot. In other words, a change in the leverage is required to produce a corresponding change in travel of a pinion along the rack to vary the feed. However, this is not adaptable to linearly reciprocating ram machines since such machines lack a pivotal driving element along which a feed control may be placed.

The principal object of this invention is an adjustable mechanism for accurately and efiiciently controlling the intermittent feed of strip stock into a machine driven by a constant linear stroke.

Another object of this invention is a mechanism associated with the adjustable mechanism for insuring the positive removal of a punch from the strip before the succeeding feed thereof.

Generally, according'to the invention, one end of a rack is pivotally connected to a fixed member and the teeth near the other end of the rack are in mesh with a pinion carried by the linearly driven ram, the pinion imparting a unidirectional drive to a roller to feed a predetermined amount of strip into the machine. The strip feed is changed simply by changing the position of the one end of the rack along the member to change the angular disposition of the rack with respect to the ram stroke and thereby control the moving distance of the pinion along the rack, the moving distance being related to the included angle between the stroke and rack.

In a preferred embodiment, a press, driven by a ram having a linearly reciprocating constant stroke, has a feeding unit which includes a common shaft with a pinion, feed roller, and unidirectional feed drive mechanism disposed thereon. A rack has one end in mesh with the pinion and the other end adjustably movable along a member angularly disposed with respect to the ram stroke. Upon the upstroke of the ram, a clutch for controlling the feed is prevented from operating until a bracket unit positively removes the punch from the strip. The strip feed is varied by changing the position of the other end of the rack along the template, the rack position controlling the rotational feed movement of the pinion therealong.

Other objects and a fuller understanding of the invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawing, in which:

FIG. 1 is a side view of the press ready to commence its downstroke with the adjustment mechanism set for a maximum feed and, in phantom, set for a minimum feed of the strip;

"ice

FIG. 2 is a side view of the press ready to commence its upstroke to feed the strip; and

FIG. 3 is a fragmentary view of another embodiment of the rack adjusting mechanism.

With reference to the drawing, the invention is illustrated as being incorporated in a hot stamp press for stamping identifying numerals on an article 9. The press includes a vertically driven ram 10 having connected thereto a holder 11 for supporting a supply reel 12 of strip 13 which is threaded around roller 14, under spring loaded

members

15 and 16 located on either side of a heated punch 17, and between pressure roller 18 and feed roller 19.

A common drive shaft 20 is supported on a feed roll unit, generally referred to at 21, and has connected thereon the feed roller 18 and a pinion 22, the pinion being held in mesh relationship with a rack 23 by bracket 24. The rack 23 has one free end 25 While the other end 26 is provided with an internally threaded sleeve 35 pivotally connected to a fixed threaded member 27 mounted on element 28, the element being mounted on the press frame 29. The threaded member 27 is angularly disposed with respect to the vertical movement of the ram stroke and feed roller 18. The rack sleeve 35 may be moved along the threaded member from" a full feed position at the upper end of 27 where the rack is positioned parallel with the ram stroke to a minimum feed position at the lower end of 27 where the rack approaches perpendicularity to the ram stroke, the direction of the ram stroke being shown by the arrow in FIGS. 1 and 2. A calibrated scale, not shown, can be provided with the member 27 for adjustment identification.

In operation, upon the downstroke of the ram 10, mounting bracket 30, connected to the holder 11 by screw 31, moves downwardly on guide pin 32. The feed roll unit 21, connected to an arm portion 44 of bracket 30 by spring 36, moves downwardly with the bracket until an adjustable stop screw 33 on the unit strokes stop member 34 to prevent any further movement thereof.

During this time, the feed roller 22 is disengaged from.

the pinion by a slip clutch (not shown) to prevent its causing spring 36 to compress against the arm portion 44 and thereby decrease the gap at 37 between the bracket element 38 and the end portion 39 of unit 21. At this time the punch begins to cut into the strip, the cutting action being completed at the termination of the downstroke as seen in FIG. 2. When ram 10 begins its up stroke, bracket 30 moves upwardly therewith causing spring 36 to release and restore the gap at 37 to its original dimension. During the release of spring 36, punch 17 is positively removed from the strip. As the ram continues its ascent to the end of the upstroke, bracket 30 engages and lifts the unit 21. Simultaneously therewith, a slip clutch (not shown) engages the feed roller with the pinion and a predetermined amount of new strip is fed under the punch as the used strip is passed between the feed and pressure rollers due to the moiement of the pinion along the fixedly positioned rac The amount of strip fed under the punch is determined by the position of the pivotally connected rack end 35 along the member 27, a handle 40 being provided on member 27 for rotation thereof to move the rack therealong. As seen in FIG. 1, upon positioning the rack in an almost parallel relationship with respect to the stroke movement of the ram, the pinion travels the full length of the rack teeth 41 and a maximum feed results.

In other words, upon the downstroke of the ram,- the pinion travels the full length of the rack teeth towards the rack end 25. Upon the upstroke and after the punch is positively removed from the strip, the slip clutch is activated to engage the pinion with the feed roller and the pinion moves upwardly towards the other end of the rack traveling over the full lengthof the rack teeth.

In the event that a minimum feed is desired, the rack end 35, as seen in phantom in FIG. 1, is positioned in an almost perpendicular relationship with respect to the ram' stroke so that a minimum movement of the pinion along the rack is obtained. Consequently, by varying the included angles between the longitudinal axis of the rack with the longitudinal axis of the ram stroke, a desired amount of strip feed is obtained. Instead of using the threaded member 27 for positioning the pivotal end of the rack, a template 45, as seen in FIG. 3, having a cut out portion 46, can be utilized. The cut out portion 46 can be a straight passage inclined with respect to the ram stroke or it may be of concave, conveX or compound curvature. The end of the rack is provided with securing means 47 for locking the pivotal end in the desired position.

In the event an accurate small feed is desired i.e., where the angle between the rack and ram stroke approaches 90, as seen by the dashed line in FIG. 3, then the curvature of the cut out portion should be such that it provides a longer moving distance for the rack end to produce a relatively smallangular change with respect to the disposition of the rack.

It is to be understoodthat the above described arrangements are simply illustrative of the application of the principles of the invention. Numerous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

1. In a strip feedingmechanism having a linearly driven, constant stroke, a reciprocating ram with a feed roller on a shaft carried by the ram, the improvement comprisingmeans' for controlling the rotation of the feed roller to determine the feed of the strip" which comprises a pinion on the shaft, a rack' for rotating the pinion,

means for holding the rack in mesh with the pinion, pivotal connecting means on one erido'f the rack, andmeans for securing the rack connecting means'at various" fixed positions so that the rack may be positioned'a't var-' ious angles with respect to the ram stroke.

2. In a strip feeding mechanism including a reciprocating ram having a linearly driven constant stroke, a shaft movable with the ram, a feed roller on the shaft, unidirectional feed means for operating the roller responsive to the movement of the ram, and a pinion connected to the shaft, the combination of a rack having teeth on one end thereof in mesh with the pinion, means for holding the rack in mesh with the pinion, means for securing the other end of the rack at various positions with respect to the stroke to change the distance of travel of the pinion aiong the rack for controlling the amount of feed by the roller.

3. In a strip feeding mechanism according to claim 2 whereby the rack is disposed in a substantially parallel relationship with respect to the ram stroke to effectuate a maximum feed by the roller.

4. In a strip feeding mechanism according to claim 2 whereby the rack is disposed in perpendicular relationship with respect to the ram stroke to effectuate a minimum feed by the roller.

5. In a strip feeding mechanism according to claim 2 whereby the other end of the rack has an internally threaded element connected thereto and the securing means comprises a member angularly disposed with respect to the stroke and having an externally threaded surface cooperating with the threaded element, and a handle connected to the member for rotation thereof to move the rack therealongto change the angular relationship between the rack and stroke;

6. In a strip feeding mechanism according to claim 2 wherein the securing means comprises a template having a cut out portion angularly disposed to the ram stroke, the curvature of the cut out portion being such that it provides a longer moving distance for the rack end to produce a relatively small angular change with respect to the disposition of the rack, and a locking element on the other end of the rack to lock the rack in the desired position on the cutout portion.

References Cited in the file of this patent UNITED STATES PATENTS 2,589,907 Weidenmiller Mar. 18, 1952 2,622,873 Wenneche Dec. 23, 1953 2,763,325 Willous Sept. 18, 1956 2,904,167 Gues's' Sept. 15, 1959

Claims

1. IN A STRIP FEEDING MECHANISM HAVING A LINEARLY DRIVEN, CONSTANT STROKE, A RECIPROCATING RAM WITH A FEED ROLLER ON A SHAFT CARRIED BY THE RAM, THE IMPROVEMENT COMPRISING MEANS FOR CONTROLLING THE ROTATION OF THE FEED ROLLER TO DETERMINE THE FEED OF THE STRIP WHICH COMPRISES A PINION ON THE SHAFT, A RACK FOR ROTATING THE PINION, MEANS FOR HOLDING THE RACK IN MESH WITH THE PINION, PIVOTAL CONNECTING MEANS ON ONE END OF THE RACK, AND MEANS FOR SECURING THE RACK CONNECTING MEANS AT VARIOUS FIXED POSITIONS SO THAT THE RACK MAY BE POSITIONED AT VARIOUS ANGLES WITH RESPECT TO THE RAM STROKE.