US3041068A - Machine for loading articles from the bottom and for transferring said articles - Google Patents

Description

June 26, 1962 H. E. SCHALTEGGER 3,041,068

MACHINE FOR LOADING ARTICLES FROM THE BOTTOM AND FOR TRANSFERRING SAID ARTICLES 6 Sheets-Sheet 1 Filed March 4, 1960 INVENTOR.

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June 26, 1962 H. E. SCHALTEGGER MACHINE FOR LOADING ARTICLES FROM THE BOTTOM AND FOR TRANSFERRING' SAID ARTICLES 6 Sheets-Sheet 2 Filed March 4, 1960 INVENTOR. HERBERT SCHALTEGGER BY 0'14") M0606 [JP/'7,

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June 26, 1962 H. E. SCHALTEGGER 3,041,068

MACHINE FOR LOADING ARTICLES FROM THE BOTTOM AND FOR TRANSFERRING SAID ARTICLES Filed March 4, 1960 a s heats-Sheet 5 INVENTOR.

HERBERT S'C'HALTEGGER BY Olum "many 4 June 26, 1962 H E. SCHALTEGGER 3,041,058

MACHINE FOR LZOADING ARTICLES FROM THE BOTTOM AND FOR TRANSFERRING SAID ARTICLES Filed March 4, 1960 I 6 Sheets-Sheet 4 INVENTOR. HERBERT SCHALTEGGER Fr c l J 6/0 ATTORNEYS.

June 26, 1962 H E. SCHALTEGGER MACHINE FOR ILOADING ARTICLES FROM THE BOTTOM 6 Sheets-Sheet 5 G} 1 ii '1" .4% W 45 v x N \1 a 0 3| Q Q E 5 5 u --1 M W a a? i i X I II} I I INVENTOR. n 3? HERBERT SCHALTEGGER 5/ m I Ma 606 M7";

June 26, 1962 Filed March 4, 1960 H. E. SCHALTEGGER MACHINE FOR LOADING ARTICLES FROM THE BOTTOM AND FOR TRANSFERRING SAID ARTICLES 6 Sheets-Sheet 6 INVEN TOR. HERBERT 'SCHALTEG GER J F/u loJ may" V 1am ATTORNEYS.

United States Patent 3,041,068 MACHINE FOR LOADING ARTICLES FROM THE BOTTOM AND FOR TRANSFERRING SAID ARTICLES Herbert E. Schaltegger, New Milford, Conn., assignor,

by mesne assignments, to Afico S.A., Lausanne, Switzerland, a corporation of Switzerland Filed Mar. 4, 1960, Ser. No. 12,739 4 Claims. (Cl. 271-29) This invention relates to improvements in machines for transferring small articles, and in particular relates to improvements in machines of the type wherein articles are taken from the bottom of an elevated stack and are lowered and transferred to another conveyor, such as a moving conveyor.

Without limitation thereto, the principle of my invention is particularly suitable for use in connection with apparatus employing a suction cup which is operative under vacuum to pick up the article from the bottom of an elevated stack in any appropriate dispenser, and which is then moved to a point at which the vacuum is relieved and the suction cup releases the article to a moving conveyor.

In many instances, with which this application is primarily concerned, it is desirable to remove labels, carton blanks or other articles from the bottom of a stationary hopper and to transfer the articles to a moving conveyor or to a receptacle which is located on a moving conveyor. It is desirable to permit this conveyor to move at a maximum speed and to transfer maximum number of articles to said conveyor per given unit of time.

Since the article is picked up from below and released from above, the suction cup should turn 180- degrees between the point of pick-up and the point of release, and should turn another 180 degrees between the point of release and the point of pick-up. The suction cup should be travelling generally vertically just before and just after the moment of pick-up and should be approximately stationary at the moment of pick-up. Furthermore, if the conveyor is located in a horizontal plane, the suction cup should be travelling generally horizontally and with maximum speed at the moment of release of the article, to permit maximum speed of the conveyor and to insure smooth transfer of the article.

In accordance with a preferred embodiment of the invention, the path of movement of the suction cup is in the form of an epitrochoid, while at the same time an additional movement is imparted to the suction cup which causes it to turn 180* degrees about the axis of its support shaft while moving between the extreme upper and lower points of the curve.

Epitrochoids and related curves are briefly discussed in Mechanical Engineers Handbook, edited by Lionel S. Marks, fourth edition (1941), pages 152 and 153. An epitrochoid is a curve traced by any point rigidly attached to a circle of radius a, at distance b from the center, when this circle rolls without slipping on the outside of a fixed circle of radius 0. If a /2c, the epitrochoid has two cusps or stops 180 degrees apart. The suction cup is caused to turn in such direction that it rotates only once while its complete curve of movement is described. The suction cup is inverted at the upper cusp or stop of the curve of its movement when it picks up the object and erect at the bottom of the curve of movement when it releases the object.

As an important preferred optional feature of the invention, cyclic means are provided for increasing the rate of rotary movement of the suction cup at the top of its path of movement, thereby accentuating the upper cusp or stop and emphasizing the vertical component of the movement of the suction cup at the top of its path 3,041,068 Patented June 26, 1962 of movement and increasing the speed of change from upward movement to downward movement of the suction cup. Furthermore, these same cyclic means decrease the rate of rotary movement of the suction cup at the bottom of its path of movement, thereby emphasing the horizontal component of movement of the suction cup and facilitating transfer of the article to the conveyor.

Other objects and advantages of this invention will become apparent from the following description, in conjunction with the annexed drawings, in which a preferred embodiment of the invention is disclosed.

In the drawings,

FIG. 1 is a front elevation of the apparatus, showing the suction cup in full lines in its lowermost position for release of the article, and in broken lines just before and just after its lowermost position.

FIG. 2 is a vertical section of the apparatus, showing the hopper and conveyor in broken lines.

FIG. 3 is a section on line 3-3 of FIG. 2.

FIG. 4 is a section on line 44 of FIG. 2.

FIG. 5 is a section on line 5-5 of FIG. 2. FIG. 5 shows various positions of the suction cup in broken lines and also shows the curve of movement thereof.

FIG. 6 is a fragmentary section on line 66 of FIG. 2.

FIG. 7 is a fragmentary section on line 7-7 of FIG. 2.

FIG. 8 is a fragmentary section on line 8-8 of FIG. 2.

FIGS. 9 12 are views similar to FIG. 7, partly in phantom, showing various stages of a cycle of movement of the suction cup. FIG. 9 shows the suction cup at the bottom or transfer point of its path of movement. FIG. 10 shows the suction cup shortly after the top of its rise from its bottom point. FIG. 11 shows the suction cup in its top position. FIG. 12 shows the suction cup shortly after it has begun to drop from its top point.

FIG. 13 is a section on line 1313 of FIG. 1.

General Description The general arrangement of the'machine will best be apparent from FIG. 14.

Vertically and laterally extending frame member 10 serves as the main support for the apparatus. As shown in FIGS; 1 and 13, said frame member 10 is provided on its rear face with one or more bosses which are formed to provide a plurality of sleeve bearings for various operating members of the apparatus. In particular, there is a main sleeve bearing 11 which turnably receives a drive sleeve 14 which extends both rearwardly and forwardly of frame member 10. Longitudinal drive shaft 15 extends turnably through sleeve 14.

Optionally, upright 10 may be provided with broadened base support 10a for stability. Forwardly of upright 10, sleeve 14 is provided with an enlarged rotary valve portion 14b about which a fixed valve portion 13 extends. A further sleeve bearing 12 around sleeve 14, forwardly of fixed valve member 13, has a rear transverse flange 12a. Said flange 12a and fixed valve member 13 are fixed to upright 10 by means of screws 9 (FIG. 2).

An enlarged spider 29 of disc-like shape is fixedly mounted upon sleeve 14 forwardly of bearing 12;

Shaft 15 extends forwardly of sleeve 14, and gear 30 is fixedly mounted upon the front end of shaft '15. A spacer washer 31 upon the front end of sleeve 14 serves to space spider 29 and gear 30.

As shown in FIG. 2, spider 29 has a bore adjacent its periphery, in which sleeve bearing 32 is received. Longitudinal shaft 33 extends longitudinally into bearing 32 and extends forwardly of spider 29 and gear 30. Gear 34 is fixedly mounted upon shaft 33 and meshes with gear 30. Adjacent the front end of shaft 33, a pair of suction cup shafts 35 extend radially therefrom, with suction cups 36 being respectively mounted upon the outer ends of. said shafts 35. It will be apparent that by turninggsleeve 14, spider 29 is rotated, thereby turning shaft 33 about the main longitudinal axis of shaft 15 and sleeve 14. As the result of the meshing of gear 34 with gear 30, shaft 33 also turns about its own axis. Gear 34 may be considered the same as. a circle rotating on the periphcry of a fixed circle represented by gear 30. Any point on the periphery of gear 34 describes a curve known as an epicycloid. The open end of suction cup 36, which is a' fixed distance radially from the center of gear 34, describes a curve. known as. an. epitrochoid.

The radius of gear 34 is preferably one-third of the radius of gear 30. If gear 30 were to rotate with uniform speed, this would result in the epitrochoid path of movement of suction cup 36. having an upper cusp or stop and a lower cusp or stop. This curve is optionally and preferably modified in a manner to be described below.

Hopper 38 is located at the top of the path of movement of suction cups 36 and carries a plurality of blanks or other articles. 39, in position for suction cups 36 to withdraw a blank 39 from the bottom of .hopper 38 at the uppermost. point of movement of said suction cups 36.

Any suitable horizontally and laterally moving conveyor 40 islocated imposition to receive. a blank 39 from suction cups 36 at the lowermost point of movement of said suction cups 36.

In order to drive sleeve 14, gear 22 is fixedly mounted upon sleeve 14 rearwardly of upright 10. This meshes with a gear 19 on longitudinal shaft 20, and said gear 19 in turn meshes with gear 18 on longitudinal shaft 17. Optionally, the three gears 18, 19 and 22 are in 1:1:1 ratio. Said. shaft 17 extends to the extreme rear of the apparatus, and sprocket 16 is mounted on the rear thereof. This sprocket may be driven by any suitable means such as the chain 16!) shown in broken lines in FIG. 14. Any suitable means for rotating shaft 17 may be employed. Optionally, shaft 17 is rotated at uniform speed but the invention is not limited to this. In fact, in some applications, itmay be desirable to increase the speed of'rotation of shaft 17 while article 39 is being transferred to conveyor 40. V

The assumed direction ofrotation of sprocket 16 is given by arrow 16a and hence is counter-clockwise when viewed from the front of the apparatus. Gear 18 turns in the same direction (arrow 18a), gear 19 turns in the reverse direction (arrow 19a), 'and gear 22 turns in the counter-clockwise direction (arrow 22a). This establishes a counter-clockwise direction of movement for sleeve 14 (arrow 14a) and spider 29 (arrow 29a). This establishes a basic clockwise direction of rotation of shaft 33' (arrow 33a).

-Without further modification, shaft 33 would make a complete rotation in movement from its upper point to its lower point and vice versa, and this is not desirable.

As is clear from FIG. 14, shaft =33 should only turn 180 degrees in movement of suction cups 36 from their top position to their bottom position. Accordingly, appropriate means are provided for turning shaft 15 in the same direction as sleeve 14, but at half the rate of rotation thereof, so as to impart the desired rate of rotation to shaft 33. In the preferred drive means, a plate 24 has a through aperture through which sleeve 14 extends turnably. Said plate 24'has a further aperture through which longitudinal shaft 25 extends turnably. In front of plate 24, gear 26 is fixedly mounted upon shaft 25 and meshes with gear 22. Preferably, the ratio of gears 22 and 26 is 2:1. Gears 27 and 28, in 1:1 ratio, are respectively fixed meshingly upon shaft 25 and shaft 15, rearwardly of plate 24.

It will be apparent that gears 26 and 27 turn in the clockwise direction (arrows 26a and 27a.) as viewed from the. front of theapparatus, and that gear 28 turnsin the counter-clockwise direction (arrow 23a). The effect is to make gear 30 rotate in the direction of arrow 30a at half the rate of rotation of gear 29. If gear 33 were stationary, gear 34 would turn in counter-clockwise direction at too great a rate of speed. The turning of gear 34} in the counter-clockwise direction of arrow 33a imparts a turning force upon gear 34 which turns it in the clockwise direction of arrow 33a. While the resultant rotation of shaft 33 is in the counter-clockwise direction of arrow 33!), the rate'of rotation of shaft 33 is such as to cause it to rotate. once per rotation of spider 29.

As an important optional and preferred feature of the invention, means are provided for cyclically varying the rate of rotation of shaft 33 in the direction of arrow 33b. In the preferred form, a simple crank arm 23 is attached by longitudinal pivot 23zz'to gear 19, and by longitudinal pivot 23b to plate 24 adjacent the upper end thereof. The result is to produce an oscillatory movement of plate 24 (arrow 24a), there being one complete oscillation of plate 24 per rotation of spider 29.

When the movement of plate 24 is in the clockwise direction, as viewed from the front of the apparatus, the result is to move gear 27 with respect to gear 28 in such a way as to increase the rate of movement of gears 27' and 28 in the direction of the arrows 27a and 28a. This increases the rate. of movement of shaft 33 in the direction of arrow 33a, and thereby decreases the net rate of rotation of shaft 33 in the direction of arrow 33b. Conversely, the oscillation of plate 24 in the counterclockwise direction causes the. rotation of shaft 33 to be increased.

Details of the Apparatus While the overall structure should be clear from the general description and from the drawings, the details of the vacuum system for the suction cups, as well as certain details of the housing, will be briefly described.

In order to support and conceal the shafts 15, 20 and 21 and associated parts, a generally cylindrical, longitudinally extending housing 50 is mounted upon the rear of frame member 10, by means of screws 56. Housing 50 has rear openings 51 and 52 through which shafts 15 and 17 respectively extend. Rear bearing assembly 53 covers opening 51 and turnably receives shaft 15. Rear bearing assembly 54. covers opening 52, and shaft 17 extends turnably through bearing assembly 54. Sprocket 16 is mounted on shaft 17 rearwardly of bearing assembly 54 The boss on frame member 50, in addition to the sleeve 11 previously mentioned, also has a sleeve 11a for reception of shaft 20 and its sleeve bearings 21, and a sleeve 11b for reception of the front end of shaft 17 and its sleeve bearings 55. 7

With particular reference to FIGS. 2-5, it will be noted that shaft 33 has a longitudinal bore 60 closed at its front end by plug 61. Shafts 35 are hollow and communicate with bore 65). Shaft 33 extends turnably through and beyond sleeve bearing 32 in bore 32a. of spider 29. The rear of bore 32a is closed by plug 32b. Diametrical bore 60a in shaft 33 provides communication between bore 60' and bore 32a behind bearing 32. Spider 29 and sleeve 14 together have a radial bore 62 which provides communication between bore 32a behind hearing 32 and longitudinal bore 63 in the wall of sleeve 14. The rear end of bore 63 communicates with radial bore 64 in sleeve portion 14b, which serves as the rotary air valve member, as previously stated.

Fixed' valve member 13' has grooves 66 and 67 in the inner periphery thereof. Groove 66 extends (as viewed in FIG. 5) in the counter-clockwise direction from a point just past the top of the bore of valve member 13 to a point near the bottom of the bore of valve member 13, for a total are somewhat under degrees. Hollow radial fitting 68 extends through a radial bore of valve member 13 into communication with groove 66, and is adapted to'be connected to any suitable means (not shown) for withdrawing air from fitting 68 in the direction of arrow 68a. Groove 67 extends across the bottom of the bore of valve member 13. Gear 67 communi cates through radial bore 67a in member 13, with the outside atmosphere. Optionally, intake air may be forced into bore 67a.

It will be understood that if only one shaft 33 is provided, only one set of air bores need be provided, and hence only one has been described. The drawing illustratively shows spider 29, sleeve 14 and valve member 13 provided with a second set of bores, in case a second shaft 33 is used. This may occur in certain applications, especially when crank 23 is omitted. Illustratively, crank 23 might be omitted if article 39 is to be dropped into a jar supplied by an indexing mechanism, rather than onto a moving conveyor.

A generally cylindrical cover 70 is provided for gears 30 and 34, the peripheral wall of cover 70 being secured to the front of spider 29. Cover 70 has -a front end opening with sleeve bearing 71, through which shaft 33 extends.

Summary of Operation While the operation of the apparatus will be generally apparent from the foregoing, the operation may be briefly summarized as follows: FIG. 14 shows the suction cups 36 at the bottom of their path of movement, in position to release article 39 to conveyor 40. In this position, the suction cup shaft 13 communicates with groove 67 and bore 67a, and hence with the external atmosphere for release of article 39. In this position, crank 23 has the position shown in FIG. 9, and plate 24 has begun an oscillation in the counter-clockwise direction, as viewed from the front of the machine (clockwise direction as taken in FIG. 9). As a result, while suction cups 36 are moving through the position of FIG. 14, the direction of movement of plate 24 is such as to retard the rate of movement of suction cups 36 in the direction of arrow 33b.

As previously pointed out, there are two principal components of rotary movement of shaft 33. One component is the movement imparted to shaft 33 as the result of the rotation of gear 34 imparted thereto by gear 30 during rotation of spider 29. The second component of a movement of shaft 33, which opposes the first-mentioned component, is that movement imparted to it as the result of the rotation of gear 30' in the direction of arrow 30a, said gear 30a being driven by gears 18, 19, 22, 26, 27 and 28. As pointed out above, the movement of plate 24 in the counter-clockwise direction about the axis of sleeve 14 (as viewed from the front of the machine) reduces the speed of rotation of shaft 26 and hence reduces the speed of the resulting rotation of shaft 33, thereby imparting resulting reduction in speed of the vertical component of movement of suction cups 35 in the position of FIG. 14.

FIG. shows the extreme limit of the movement of plate 24, which movement has been shown at an intermediate point thereof in FIG. 9. This cor-responds to the position of suction cup '36 shortly after article 39 has been released. Plate 24 now begins to turn about the axis of sleeve 14 in the clockwise direction as viewed from the front of the machine (counter-clockwise direction as viewed in FIG. 11). FIG. 11 shows plate 24 at an intermediate point of its movement in its counter-clockwise direction. This results in an increase in the direction of arrow 33a in the rate of turning of suction cups 36 when they are in the broken line position of FIG. 14 for pick-up of article 39 from hopper 38. During the vertical upward movement of suction cups 36, the suction cup shafts 35 are in communication with groove 36 of fixed valve element 35, and accordingly the cups 36 are under suction. This suction continues after article 39 has been picked up by suction cups 36, and until it is released later on.

FIG. 12 shows the position of plate 24 at the conclu- 6 sion of its movement, an intermediate point of which is shown in FIG. 11. It will be apparent that FIG. 12 corresponds to the downward movement of suction cup 33, before it reaches its position of FIG. 9.

One-half of the path of movement of suction cups 36 is indicated diagrammatically by the curve 1 in FIG. 5, and the other half of the curve should be readily apparent without a showing. It will be apparent that the curve 1 is a modified single cusp epitrochoid, the modification of the curve resulting from the provision of the oscillatory plate 24. The curve 1 corresponds to the position at each instant of the center of the base of suction cup 36. Since the rotary movement of suction cup 36 is retarded at the base of the curve, the base of the curve is flattened and made more nearly horizontal. Since the rate of movement of suction cup 36 is increased at the upper portion of curve 1, the upper portion of curve 1 is of increased steepness and the cusp is accentuated.

Curve 1, accordingly, represents a highly desirable curve of movement of suction cups 36 since the major component of movement of suction cups 36 is horizontal just before, when, and just after article 39 is released to conveyor 40, and since the major component of movement of suction cups 36 is vertical just before, when, and just after article 39 is picked up from the bottom of hopper 38, with an abrupt reversal of movement at the instant of pick-up.

Modifications It will be apparent that various changes, omissions and additions may be made in the invention without departing from the scope and spirit thereof. Most of these changes require no extended discussion. As one possible modification, in certain applications crank 23 may be removed so that plate 24 does not oscillate.

As another important modification, it is not always necessary that the points of pick-up and release be degrees apart. For example, the suction cups 36 may release article 39 to an inclined conveyor 40 before the lowermost point of curve 1 is reached. Furthermore, by changing the gear ratios it is possible to provide a path of movement of suction cups 36 which has, for example, two or more cusps. This makes it possible to provide for pick-up of an article at a cusp located otherwise than at the top of the curve of movement of suction cups 36 and at a point disposed other than 180 degrees from a flattened portion of the curve of movement of suction cups 36 which is suitable for release of an article. The important principle of the invention is that pick-up of an article he at a cusp of the curve of movement of the suction cups, and that release of an article be at a relatively flat portion of the curve of movement.

If there is more than one cusp in the curve, obviously the relationship of the pick-up and release points may be different from that shown in FIG. 14 and other views, but the principle of the invention is still the same. Furthermore, even in the event that a modified curve of movement is employed, the oscillatory plate 24 may still be employed to accentuate the cusps and to accentuate the fiat portions of the curve of movement.

What is claimed is:

1. In cyclical apparatus for transferring articles from the bottom of a hopper onto a horizontal conveyor located below the hopper; a longitudinally extending shaft, a suction cup shaft extending radially from said longitudinal shaft, a suction cup mounted upon the outer end of said suction cup shaft, a first drive member having a main longitudinal axis which is offset from the axis of said longitudinal shaft, said first drive member being rotatable about said main axis, means for rotating said first drive member, said suction cup shaft being rotatable about its axis and about said main axis, means coupling said first drive member and said suction cup shaft for rotation of said suction cup shaft about said main axis upon rotation of said first drive member, a second drive member also having as its axis said main longitudinal axis and being rotatable thereabout, means for rotating said second drive member, means coupling. said second drive member and said shaft for rotating said suction cup shaft in selected direction upon rotation ofsaid drive members, so that said suction cup extends vertically upwardly from said shaft to the bottom of saidhopper at one point of a cycle ofsaid apparatus and then turns so as to extend vertically downwardly from said shaft to said conveyor at an inter-- mediate point of said cycle of said apparatus and then returns to its first mentioned condition when the apparatus returns to said one point of its cycle, and means coupling said respective means for rotating said first drive member and said second drive member and responsive to one of said respective means for increasing the speed of. rotation of said shaft just beforeand just after said suction cup extends to said hopper so that said suction cup moves mainly vertically at'that' time and for decreasing the speed of rotationof said shaft just before and just after said suction cup extends to said conveyor so that said suction cup moves mainly horizontally at that time.

2. Transfer apparatus comprising. a first drive member,

a seconddrive member having a main longitudinal axis and being mounted to be turnable thereahout, said first drive member extending concentrically turnably about said second drive member, a longitudinally extending shaft mounted upon said first drive member so as to be turnable about the shaft axis, said shaftaxis being offset from said main axis, a suction cup shaft extending radially from said longitudinal shaft, a suction cup mounted upon the. outer end'of said suction cup shaft; meshing first and second gears respectively mounted upon said second drive member and said longitudinal shaft, 21' third gear mounted upon said first drive. member, means including a fourth gear for rotatingsaidt third gear to rotate said first drive member, means for. rotating'said second drive member, a crank'having one end attached to: said fourth gear, a plate' mounted on said apparatus so as to be turnable. about a longitudinal axis and attached. to the other end of said crank for oscillatory movement of' said: plate;v alongitudinal stub shaft on said plate, and meshing fifth and sixth. gears respectively upon said stub shaft and said second:

drive member for respective advancement. and retardation of the rate ofrotation'ofsaid first drive member corresponding to respective oscillatory movements of said plate.

3.. In. cyclical apparatus for transferring articles from the bottom of a hopper onto a horizontal conveyor located below the hopper, said apparatus having a main longitudinal. axis; a rotary shaft parallel to said: main, axis, an air suction cup extending radially from said support shaft, first means for rotating said shaft about said main axis, second means for rotating said shaft about its own axis, and means coupling said first means andsaid second means so that said suction cup extends vertically upwardly from said shaft to the bottom of said hopper at one point instant of a cycle of said apparatus and then turns so as to extend vertically downwardly from said shaft to said conveyor at an intermeditae point of said cycle of said apparatus and then returns to its first-mentioned condition when the apparatus returns to said one point of its cycle, said coupling means including means for increasing the speed of rotation of said shaft just before and just after said suction cup extends to said. hopper so that said suction cup moves mainly vertically at that time and for decreasing the speed of rotation of said shaft just before and just after said suction cup extends to said conveyor so that said suction cup moves mainly horizontally at. that time.

4. Apparatus for transferring articles from the bottom of a hopper onto a receptacle moving along on a conveyor below said hopper, comprising a frame, a hollow rotary shaft supported on saidframe, arotary member mounted on said hollow shaft, a rotary support shaft mounted at one end thereof on said rotary member in spaced. and parallel relationship to the axis of rotation thereof,.a first gearfixedly mounted on said support shaft adjacent said one end thereof, air suction cups fixed to and radially extending from said support shaft adjacent its other end, a further rotary longitudinal shaft extending through said hollow shaft, a second gear fixedly mounted on said further shaft in meshing relation with said first gear, drive means for rotating said further shaft oscillating coupling means between said hollow shaft and said further shaft for cyclically varying the speed of said further shaft relative to said hollow shaft, a source of vacuum and means for alternatively connecting the air suction cups with said source of vacuum and the atmosphere.

Pritchard Apr. 15, 1952 Faeber Sept. 8, 1959

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