US2911779A - Tucking mechanism for wrapping machines - Google Patents

Description

NOV. 10, 1959 w LUCZEK ETAL TUCKING MECHANISM FOR WRAPPING MACHINES 3 Sheets-Sheet 1 Filed Jan. 1'7, 1957 WA TOR EYS INVENTOR WALTER LUCZEK CEDRIC E. CROSS WM 2? Fillvlllt l r kll NOV. 10, 1959 w ucz EI'AL I 2,911,779

TUCKING MECHANISM FOR WRAPPING MACHINES Filed Jan. 17, 1957 3 Sheets-Sheet 2 INVENTOR WALTER LUCZEK CEDRIC B. CROSS BY A w ATIO NEYS FIG. 2

NOV. 10, 1959 w, ucz EIAL TUCKING MECHANISM FOR WRAPPING MACHINES 3 Sheets-Sheet 3 Filed Jan. 17, 1957 INVENTOR TUCKING MECHANISM FOR WRAPPING MACHINES Walter Luczek, Indian Orchard, and Cedric B. Cross,

Monson, Mass., assign'ors to Package Machinery Company,.East Longmeadow, Mass., a corporation of Massachusetts Application January 17, 1957, Serial No. 634,716 3 Claims. (Cl. 53-378) The present invention relates to wrapping machines of the type wherein articles are continuously advanced in a straight line as the wrapping operation is carried out and more particularly to tucking mechanism forarticles partially wrapped in this type of machine.

The machine disclosed .in application Serial No. 439,- 682, filed June 28, 1954, now U.S. Patent No. 2,810,246, is illustrative of the type of Wrapping machine referred to above. While that type of machine aifords rates of operation hitherto unobtainable, it does not lend itself to the use of conventional techniques in tucking the ends of a wrapper encircling the article. It is, therefore, the object of our invention to provide improved tucking mechanism for wrapping machines which will enable such machines to take full advantage of the inherently high rates of operation which they possess. Another object of our invention is found in the simple, reliable and economical tucking mechanism for wrapping machines generally.

Our invention resides in a novel combination of parts wherein the leading portion of a wrapper extending from and encircling an article rides against and is foldedinwardly by one tucker member while a second tucker member is moved in proper timed relationshipto overtake and fold inwardly the trailing portion of the extended wrapper as the article is continuously advanced in a straight line and wherein the tucking members are relatively thin and project from a pair of rotors. v

The various objects of the invention and its detailed novel aspects will be more readily apparent from a reading of the following description of twopreferred embodiments, makingreference to the accompanying drawings, and the particular novelty thereof .pointed out in the appended claims.

In the drawings: a

Fig. 1 is a side elevation, with certain frame members omitted, showing the portion of a wrapping machine in which the tucking operation is carried out by our improved mechanism;

Fig. 2 is a section taken generally on the lineII-Jl in Fig. 1;

Figs. 3 through 7 inclusive are plan views of thetucking members seen in Fig. 1 showing the progressive positions which they assume in performing a tucking operation;

Fig. 8 is an end view of a tucked package.

For illustrative purposes our tucking mechanism is herein disclosed in association with a high speed wrapping machine as disclosed inthe above-referred to application. It will be understood, however, that this in no way indicates that our invention is restricted to use with this particular type of wrapping machine. Many wrapping machine components seen in that application (and particularly Fig.'21 thereof) will be found in equivalent form in Fig. 1, as will now be described.

As seen in Fig. 1 and as in the mentioned application, partially wrapped articles A are yieldingly gripped by jaws 20, 22 extending from endless roller' chains 24,

nited States Patent which chains are driven bysprockets 26 and then .pass around a second set of sprockets, not shown. The chains 24 are guided by upper and lower rails 27 and the jaws 20, 22 have lugs 29 which ride on fixed ledges 31 (see also Fig. 2) so that articles A will be advanced rectilinearly as in the straight line path illustrated. Articles gripped in the jaws 20, 22 have a draped wrapper W, the depending ends of which are encircled about the article as it passes above a rotating bail member 28 and onto a ledge 30 all in a novel manner fully described in the named application. The bail member 28 rotatesin timed relation to the movement of the articles inasmuch as it is driven through a sprocket 32 and chain 34 which is powered by a sprocket 36 fast upon the same shaft 38 as the sprockets 26. a

The tucking mechanism of the present invention is driven in timed relation to the movement of the articles carried in the jaws 20, 22 by being driven from a common power source. That is, a sprocket 38 is arranged to rotate with the bail sprocket 32 as by securing both sprockets on a shaft 40 which shaft is journaled in the side frames of the wrapping machine. A desired rate of operation of the tucking mechanism may be obtained by passing a roller chain 42 around a two diameter sprocket 44. From the second diameter of the sprocket 144 a roller chain 46 passes around a sprocket 48 secured toa shaft 50 which is journal'ed on the side frames (Fig.2) and which is the main power shaft for rotating our tucking mechanism. t

In order to perform tucking operations, simultaneously. on both ends of an article we have provided two tucking units which are indicated generally by the reference characters 52, 54 in Fig. 2. Each unit, .by way of-illustrating our invention, comprises two superposed rotors 56, 58 which respectively carry blades or tuckers 60, 62. Since the units 52 and 54 are identical in all respects a detailed, description of only one unit will be given,=w hich description may be applied to either of the units and like reference characters will be found on the corresponding parts .of the two units.

The rotors 56, 58 are rotated in the same direction but at diiferent speeds .by the now to be described arrangement which provides an operative connection witlrthe main power shaft (for the tucking mechanism) 50. The rotors 56, 58 (Fig. 2) are carried, through means more fully described below, on a box-like frame .64 which is slidably mounted on a transverse shaft 66 securedat its ends to the side frames of the machine. A threaded shaft 68 is journaled on the side frames and exteriorly provided with a hand wheel 70. The shaft 68 is threadably received by a collar 72 on the frame 64, right and left hand threads are respectively provided onthe opposite ends of the shaft 68 so that the tuckingunits 52 and 54 may be simultaneously adjusted inwardly or outwardly to bring the rotor blades 60, 62 into a desired transverse relation with the wrapper W which is to be tucked.

With this transverse adjustment in mind, it will be seen that we have provided a spline connection, employing a key 73 (-Fig. 2) between the shaft 50 and a bevel gear 74 which is rotatably mounted on abracket 76 bolted to the under side of the frame 64. The gear 74 meshes with and drives a second bevel gear 78 keyed to a verticalshaft .89 which is journaled in the frame 64. Also secured to the shaft 80 and within theframe 64 are spur gears 82, 84. Axial movement of the shaft 80 is prevented by the hubs of the gears 78 and 84 bearing against opposite sides of the lower portion of the frame 64. The spur gear 84 meshes with a matinggear6 which is pinned to a second vertical shaft. 88 which is also journal'ed on the frame 64. The upper rotor 56 is adjustably secured to the upper end of the shaft 88 as by a set screw 90 and thus will rotate with that shaft at a 3 rate determined, in part, by the ratio between the gears 84 and 86.

The spur gear 82 meshes with a mating gear 92 formed on the lower end of a sleeve 94 which is rotatably mounted on the shaft 88 and journaled in the upper portion of the frame '64. The lower rotor 58 is adjustably secured to the upper end of the sleeve 94 as by a set screw 96 and thus will rotate with that sleeve and at a rate determined, in part, by the ratio between the gears 82 and 92. Axial movement of the shaft 88 is prevented by the l91ub of the gear 86 and a collar 98 secured to the sleeve With the above arrangement it is possible to vertically position the rotor blades 60 and 62 so that their paths of rotation will intersect the path of travel of the portion of a wrapper W which extends beyond each end of the article about which it is encircled as is illustrated in Figs. 2 and 3. Preferably the blades 60 and 62 should. pass as closely as possible to the horizontal centerline ofthe articles, and this can be obtained by adjustment of the set screws 90 and 96 to properly locate the rotors 56, 58 on the shaft 88 and sleeve 94 respectively. The vertical adjustment of the rotors may be facilitated by a collar 99 which is secured to the sleeve 94 by a set screw 100. The collar 99 also facilitates angular adjustment of the rotors 56, 58 when the set screws 90 and 96 are loosened to bring the rotor blades 60, 62 into a desired relative position so that they will rotate in proper timed relation to the movement of an article as will be more apparent from the description set forth below of the tucking operation.

As mentioned, the rotor blades 60, 62 rotate in paths which intersect the path of movement of the wrapper extension or extended portion of a wrapper W and preferably as close as possible to the horizontal centerline of the article. In this embodiment of our invention it is also preferable that the rotor blades 60, 62 be very thin as well as being very close together in a vertical sense. To further particularize, the features of this embodiment of our invention are ideally suited, though not necessarily limited to the formation of an end tuck of the type illustrated in Fig. 8 as will be more readily apparent from the following description of their operation.

The start of the tucking operation for this type of tuck is seen in Fig. 3. The lower rotor blades 62 have, in Figs. 3 through 7, been shaded to facilitate their identification in those figures. An article A is being advanced along a straight line in uninterrupted fashion past the rotors 56, 58 as is indicated by the arrow associated with the article A. During the intersecting portions of their paths, the rotor blades 60, 62 move in the direction indicated by the respective arrows so that each blade has a component of motion extending in the same direction as the movement of the article A. The rate of rotation of the rotor 56 is such that the article will overtake the blade 60a as will be appreciated by comparing the relative positions of the article and rotor blade 60a in Figs. 3 and 4. The rotor 58 is rotated at twice the rate as the rotor 56 so that the rotor blade 62a will overtake the article A as it is advanced and engage the trailing portion of the extended wrapper W as can be appreciated from again comparing Figs. 3 and 4 and will be particularly seen in Fig. 5. Also in Fig. 5 it will be seen that as the article A continues to overtake the rotor blade 60a the leading portion of the extended wrapper is folded inwardly in a progressive manner as will be more fully appreciated from viewing Fig. 6. Simultaneouly the faster rotating blade 62a is folding the trailing portion of the extended wrapper inwardly as the article continues its uninterrupted advancement. Fig. 7 shows the position of the blades 60a and 62a as the tucking operation nears its completion. The timing of the rotor blades with respect to the advancement of the article allows them to swing clear of the tucked wrapper end after the tucking operation is completed and as the article continues its rectilinear advancement towards further instrumentalities which will complete the wrapping operation.

This last-described relationship of the rotor blades is illustrated in Fig. 3 by the blades 60b and 62b and the article A as the completed tuck, seen in Fig. 8, is formed. We have found it preferable to provide adjacent and beyond the rotors 56 and 58 retaining bars 102 and 104 which temporarily restrain the extended wrapper end in its tucked relation until the above-mentioned further instrumentalities can dispose of the tucked end in the manner desired. These further instrumentalities are not essential to the present invention but may include a heat sealing bar which seals the tucked end and then further instrumentalities which fold the sealed end underneath the package and secure it by heat sealing to the underneath side of the package to complete the packaging or wrapping operation. During the tucking operation, the article has been positively gripped by the jaws 20, 22 to maintain, at all times, a proper relationship between the article and the blades 60, 62, all of which demonstrates the preferability of this type of conveyor.

While we have found that it is preferable that the rate of rotation of the rotor 58 be twice that of the rotor 56 and that the slower moving rotor have twice the number of blades as the faster moving rotor, and while We are able'to perform with this arrangement, a successful tucking operation at a very rapid rate of speed it will be appreciated that other numbers of blades and other speed ratios could successfully be employed so long as the sequence of relative motions between the extended wrapper and the rotor blades 60a and 62a as illustrated, in Figs. 3 through 7, are maintained. Further note should be taken that it has been found preferable for the lower rotor to be the slower'rotor where the overlapped portion of the wrapper is slid along the ledge 30.

From the above it will be readily appreciated that we have provided tucking means which are capable of operation at extremely high rates of speed and that in doing so' we have uniquely arranged one tucker which is engaged by the leading portion of an extended wrapper to fold that portion inwardly and a second tucker which is movable into and out of the path of the extended wrapper with a component of movement in the same direction as and at a rate faster than the rate of the article so that the second tucker overtakes and folds the trailing portion of the extended wrapper. The movements of the tuckers are set in predetermined timed relation to the movement of the article so that the leading and trailing portions of the extended wrapper may be folded or tucked in the desired manner, whereby successive partially wrapped articles are tucked at a very rapid rate.

Having thus described our invention what we claim is novel and desire to secure by Letters Patent of the United States is: l

1. In a wrapping machine, means for rectilinearly advancing in uninterrupted fashion and in predetermined spaced relationship articles encircled by a wrapper extending beyond the article; tucking mechanism comprising two coaxially mounted rotors having relatively thin blades disposed in closely adjacent, spaced parallel'planes which planes are also parallel to the horizontal plane through which: the articles are advanced with the path of movement of the rotor blades intersecting the path of movement of the extended wrapper, means for continuously rotating said rotors in predetermined timedrelation to the movement of an article and in a direction such that their blades are moving in the same general direction as the extended wrapper when their paths of movement intersect, the speed of rotation of one rotor being such that the peripheral rate of its blade is less than the rate of the article and .the speed of rotation of the other rotor being such that the peripheral rate of its blade is faster than the article whereby the leading portion of the extended wrapper will overtake and be folded inwardly by the blade of the one rotor and the blade of the other rotor will overtake the trailing portion of the extended wrapper and fold it inwardly all as the article is moving. a

2. In a wrapping machine tucking mechanism as set forth in claim 1 wherein said one rotor has twice the number of blades as said other rotor.

3. In a wrapping machine, a conveyor for rectilinearly advancing in uninterrupted fashion and in predetermined spaced relationship articles encircled by a wrapper the ends of which extend beyond'the article, said conveyor comprising jaws for gripping the leading and trailing sides of each wrapper-encircled article to positively maintain it in said spaced relationship, and tucking mechanism comprising a tucking unit on each side of the conveyor for simultaneously tucking opposite ends of the extended wrapper, each of said tucking units including two multi-bladed rotors disposed in closely adjacent parallel planes which planes are also parallel to the horizontal plane through which the articles are advanced as well as being closely adjacent the horizontal centerline of the articles, said rotors being superposed to rotate about a common axis with the paths of movement of the rotor blades intersecting the path of movement of the extended wrapper, means for rotating said rotors in predetermined time relationship to the movement of an article and in a direction such that their blades are moving in the same general direction as the extended wrapper when their paths intersect, one of said multi-bladed rotors having a given number of equi-radially spaced thin blades, the speed of said one rotor being such that the peripheral rate of its blades is less than the rate of the articles, the other of said multi-bladed rotors having half the number of blades as said one rotor which blades are thin and equi-radially spaced around said other rotor, the speed of said other rotor being such that the peripheral rate of its blades is greater than the rate of the article, whereby the leading portion of the extended Wrapper will overtake and be folded inwardly by one of the blades on said one rotor and one of the blades on said other rotor will overtake the trailing portion of the extended wrapper and fold it inwardly, the two tucking units thus performing the tucking operation on both ends ofthe wrapper-encircled article as it is continuously advanced.

References Citedin the file of this patent UNITED STATES PATENTS 1,350,608 Harriss Aug. 24, 1920 2,144,265 Milmoe Ian. 17, 1939 2,625,778 Wood Jan. 20, 1953 2,634,564 Bergstein Apr. 14, 1953

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