US1893990A

US1893990A - Wrapping machine

Info

Publication number: US1893990A
Application number: US555829A
Authority: US
Inventors: Grover Frederick
Original assignee: Forgrove Machinery Co Ltd
Current assignee: Forgrove Machinery Co Ltd
Priority date: 1930-11-07
Filing date: 1931-08-07
Publication date: 1933-01-10
Anticipated expiration: 1950-01-10

Description

Jan. 10, 1933. F. GROVER WRAPPING MACHINE Filed Aug. '7. 1951 4 Sheets-Sheet Jan. 10, 1933. F. GROVER WRAPPING MACHINE Filed Aug. '7. 1931 4 Sheets-Sheet 2 Jam. l0, 1933. V F 4@ROVER 1,893,990

WRAPPING MACHINE Filed Aug. 7. 1931 4 Sheets-Sheet 5 Patented dan. l0, 1933 STATES Leases@ FREDERICK GRVER, OF LEEDS, ENGLAND, ASSIGNO'R T0 THE FORGBOVE MAUHINERY CGIPANY LIMITED, OF LEEDS, lTNCzIaAND WBAPPING MACHINE Application led August 7, 1981, Serial No.555,829, and in Great Britain. November 7, 1980.

The object of this invention is to wrap cylindrical objects such for instance as sugar sticks made by confectioners, lozenges or coins in column formation, and an such similar articles whichon assembly in columns are built up into cylindrical form. ln the case of sticks having a right cylindrical :form the ends of the stick may be tapered round or flat at either or both ends. Uctagonal lozenges and elliptical objects may also be wrapped in the apparatus and for the sake of brevity the sticks and other articles or columns of articles to be wrapped are hereinafter termed cylindrical objects.

The closing of the ends of the tubular Wrapper extending beyond the cylindrical object may be effected by twisting when the wrapper is suitable for such treatment, or by folding by means of folders capable of forming segmental tucks in sequence to cover the ends of the cylindrical object.

One particular purpose of the invention is to enable cylindrical objects to be wrapped with cellophane, which is extremely diiicult to handle mechanically' owing to the instability of such cellophane when drawn sayfrom a reel into a single layer. The cellophane is extremely sensitive to atmospheric conditions of temperature and humidityy which results in unforeseen local distortions. 'lhe disturbing eilect of these distortions on the wrapping operation must be prevented by the mechanism controlling the cellophane during the processes of drawing the sheet from the reel, cutting it, andwrapping it tightly around the article to be Wrapped.

Generally, the invention consists in the combination of two cylindrical formers concentrically arranged and spaced apart, wrapper grippers on lsaid cylindrical formers, means for rotating'said-ormers for Winding a wrapper around said formers, and a pocket for supporting between said formers and concentric therewith a cylindrical objectto be wrapped in said wrapper, said pocket having an inclined wall whereby the cylindrical object tends to move upwardly free from the pocket when the wrapper is carried around the cylindrical object. p

A further feature of the invention consists 'in providing means, such as twisting grippers, for gathering in the ends of the wrapper about the ends of the cylindrical object spaced apart from said cylindrical formera and providing means for feeding the pockets to said twist gripper-s and for holdlng the wrapper about the cylindrical object while it 1s e The invention will now be described with reference to the embodiment shown upon the accompanying drawings, wherein lig. l illustrates a longitudinal sectional elevation of a fragment of a wrap ing machine lfor wrapping cylindrical o jects in tubular wrappers, according to this invention.

Fig. 2 is a fragmentary sectional yiew on the line 1li-ll in Fig. l.

Figure 3 illustrates a part of one of the end grippers drawn to an enlarged scale.

Fig. 4 shows one of the pockets'drawn to an enlarged scale and illustrates how the cylindrical object is freed from the walls of the pocket by the action of winding the wrapper around its cylindrical surface.

Fig. 5 illustrates dia rammatically how.

the cylindrical object is aterally supported.

lFigs. 6, 7 and 8 illustrate diagrammatically the cylindrical object and wrapper in three successive stages of the wrapping operation.

Fig. 9 illustrates a modification of the final stage of the Wrapping operation.

Figures 10 and l1 illustrate in side and end views respectively one of the twist grippers.

n the example of construction shown upon the .accompanying drawings, a chain A is provided which carries a series of openended pockets B. The chain has imparted to it a step by ste movement by means of the Maltese wheel fixed on a chain sprocket (not shown), said wheel bein actuated by a driving member D in a wellnown manner. The cylindrical objects E are placed in the pockets and are lcarried along by the chain into a number of successive ositions'. In one of these positions the poc et comes to rest between two roundformers F, `F1 of the same or nearly the same diameter as the cylindrical object in the pocket. The formers F, F1 are placement or falling-out of the cylindrical object when this arrives between the formers. Each former is provided with a flat s ring clip or gripper H adapted to grip the side of a wrapper adjacent its leading edge against the former. The flat spring clip or gripper H is pivotally mounted at H1 on a lug F* car- ,ried by an extension Fz of each former and is provided with an arm H2 which extends through a slot in said extension F2 and engages in a slot I in the end of a gripper actuating rod I1. The gripper actuating rod is operated by an arm Iz shown in Figi 2, actuated by a cam or other mechanism (not shown) in the cycle of the machine operation to cause/che gripper to open to receive the wrapper, to close the gripper to grip the wrapper during the wrapping operation, and, finally, to open the gripper after the wrapping operation to release the wrapper.` When the gripper is stationary, it is located in such a position as to admit the edge of the wrapper J moved forward by feeding mechanism (not shown). The gripper is then closed and in this position the leading edge of the wrapper lies parallel to the axis of the cylindrical object, and the wrapper extends tangentially to the cylindrical object in the direction of length of the wrapper, as shown in Fig. 6, which is the initial position of the wrapping operation. The outer sides of the wrapper adjacent the leading edge will thus be gripped by the grippers so that by simultaneous rotation of the formers, the leading edge will be moved around the cylindrical surface of the object, while the remaining portion of the wrapper will be gradually wrappedI around the cylindrical surface of the object against which it will be held by the pocket B. The movement of the leading edge of-the Wrapper around the cylindrical surface of the object will be facilitated by the object being free to rotate as the winding proceeds.

It might he thought that the central part of the leading edge of the wrapper would crumple when entering between the cylindrical object and the pocket wall. This, however, is obviated by causing the formers F, F1 after the wrapper has been gripped to separate slightly in an axial direction., which is effected by levers L operated by cam mechanism. By this separationfof the foi-mers the leading edge of the wrapper is pulled taut the foi-mers.

enough to resist the crumpling effect which might be obtained with an otherwise unstable leading edge. Further precaution is made by so shaping the pockets that in the action of winding on the wrapper, the rotation of the cylindrical object has the effect offreeing rather than wedging it against the walls of the pocket. This is attained by providing the pocket with a wall B1 which is inclined upwardly and forwardly up which the eylindrical object tends to move from a position shown in dotted lines to a position shown in full lines in Fig. 4, when the wrapper is being moved around its cylindrical surface. Such freeing action is well understood in the construction of silent pawls and the like.

The formers are rotated by means of tooth wheels K fixed thereon and meshing with further tooth wheels K1 which are driven from the driving mechanism of the machine. wheel K is wider than the wheel K1 and is so arranged as to permit of axial movement of lVhen the formers have been rotated suiiiciently to wind on the cylindrical object the required length of wrapper, rotation of the formers will cease and the spring grippers will then be released. The formers and grippers are then withdrawn in an axial direction clear of the tubular ends of the `wrapper by means of the lever L which is operated by cam mechanism. Provision may be madefor the ingress of air to the spaces vacated by the formers on their withdrawal. In order to prevent lateral displacement of the Wrafpper in the pocket during Withdrawal of the ormers, two thin blades Gr1 (Fig. 5) are provided in continuation of the rails G, these bladeslying one between each end of the cylindrical object and the innermost end of the adjacent former, said blades being of such segmental shape as to impinge against the outer edges of the cylindrical ob]ect to prevent lateral displacement thereof, while not interfering with the formation of the tubular wrapper.

It might reasonably be expected that inasmuch as the wrapper is wound around the formers and eventually is wound over the springgrippers,thatwhenthelatter aremoved outwardly to release their grip, the action of release would either loosen the 'whole end of the wrapper or alternatively, the spring grippers would tear their way through the tubular ends of the wrapper. This effect is avoided by constructing the cylindrical surface adjacent the ends of the former with a flat portion F3 with which the gripper H is adapted to contact so that the surface where the grippers act is of less diameter than that of the cylindrical surface ofthe former by which the tubular wrapper is formed. By

this artifice the tubular wrapper is tightly wound around the extreme ends of the formers but that portion of the tubular wrapper containing the grippers is of loose spiral The A' formation, and is therefore capable of easy been withdrawn, the wrapper is inthe position shown in Fig. 7, which is the finalposition ofthe wrapplng operation After the wrapping operation has been completed and the formers withdrawn, the

pocket containing the wrapped object passes' along the machine between the guide rails G2 until the wrapper and object are brought in between revolving grippers. These gulde rails G2 are located one at each end 'of the cylindrical object so as to impinge on the ends of said object, said rails being slotted for the passage of the tubular wrapper ends.

Such revolving grippers indicated by N in Figure l are shown in Figures l0 and 11 of the accompanying drawings and comprise two fiat gripper platesN1, N2 each fixed to one end N1 of a lever N4 pivoted at N5 on a bracket N8 and carrying at its other end N7 a bowl N8 which is held against the periphery of a cam O by the spring N1. rlwo cams are provided one for each gripper plate, these cams being ixed on an extension 01 of the cam operatingr gear wheel O2 meshing with the driving gear wheel O2. rlhe bracket N2 is fixed by a screw N1o to a shaft N11 which passes through the cam operating gear wheel 02 and is formed with gear teeth N12 meshing with the driving gear wheel N13. The driving gear wheels O5 and N13 drive the gears 02, N12 in such a timed relationship that the gripper plates N1, N2 are moved together and effect the twisting of the ends of the wrappers before being allowed to be opened by the action of the.` springs N. The

twist grippers are movable endwise to bring the gripper plates N1, N2 when separated against the untwisted projecting wrapper ends and to withdraw them from the twisted wrapper ends by the engagement with the shaft-N11 on the gear N12 of an arm P, actuated by cam mechanism. These twist grippers are rotated in opposite directions to twist the wrapper ends. The gripper plate N1 is resiliently retained on the end Na by the springs N1 in order that it may give to accommodate the thickness of wrapper gathered between said plates. Two of these revolving twist grippers are provided. one at each end of the pockets and these twist grippers are adapted to grip the projecting open cylinder ends of the wrapperand are adapted to be rotated ingopposite directions in order to twist said ends into the position shown in Fig. 8 which shows the wrapper at the end of a twisting operation. The wrapper in the pocket continues to be carried forward by the chain until it reaches a position at the end of the conveyor where the wrapped objec-t is charge ta le O, as shown in Fig. 1.

In a modified construction where end folds are required instead of twisted ends, the pockets are brought consecutively opposite folding blades of known construction which act to turn in the ends of the wrapper, as shown in Fig. 9.

What I claim as my invention and desire to secure by Letters Patent is l. A wrapping machine, comprising, in combination, two cylindrical foi-mers concentrically arranged and spaced apart, wrapper grippers on said cylindrical formers, means for rotating said formers for winding a wrapper held by said grippers around said formers, a pocket for supporting between said formers and concentric therewith a cylindrical object to bc wrapped in said wrapper, said pocket having an inclined wall whereby the cylindrical object tends to move upwardly free from the pocket when the wrapper is carried around the cylindrical object, means for moving said formers outwardly to withdraw them from the wrapper after the latter has been wound; two

oppositely rotatable twist grippers spaced apart from said cylindrical formers for twisting the ends of said wrapper; means for feeding said ocket from a position in which the cylindrical object and its wrapper are between the formersv to a position in which they are between the two twist grippers, and means for maintaining the wrapper aroundthe cylindrical object while it is fed from the formers to the twist grippers.

2. A wrapping machine, comprising, in combination, two cylindrical formers concentrically arranged and spaced apart, grippers on said cylindrical formers for a wrapper, means for rotating said formers for winding said wrapper around said formers, pockets for supporting between said formers and concentric therewith cylindrical objects vto b e wrapped in said wrapper, said pocket-s having an inclined wall whereby the cylindrical object tends to move upwardly free from the pocket when the wrapper is carried.

around`the cylindrical object, meansv for moving said formers outwardly from each other whereby after being gripped by said grippers the wrapper is pulled taut and after winding the formers are retracted from opposite ends of said wrapper, two oppositely rotatable twist grippcrs spaced apart from said cylindrical formers for twisting the ends precipitated on to an inclined dis-` of said wrapper, means for feeding said pers on said cylindrical formers for a wrapper, means for rotating said ormers for winding said wrapper around said formers, pockets for supporting between said formers and concentric therewith cylindrical objects to be wrapped in said wrapper, means for moving said formers outwardly from each other whereby the formers are retracted from opposite ends of said wrapper, means spaced apart from said cylindrical formers for gathering the ends of said wrapper on to the ends of the cylindrical object, /means for feeding said pockets from the formers to the twist grippers, and means for maintaining the wrapper around the cylindrical object while it is fed fromthe formers to the twist grippers.

4. A wrapping machine, comprising, in combination, two cylindrical formers concentrically arranged and spaced apart, grippers on said cylindrical formers for a wrapper, means for rotating said formers for winding said wrapper around said ormers, pockets for supporting between said formers and concentric therewith cylindrical objects to be wrapped in said wrapper, said pockets having an inclined "wall whereby the cylindrical objects tend to move upwardly free from the pocket when the wrapper is carried around the cylindrical objects, means for moving said formers outwardly from each other whereby after being gripped by said grippers the wrapper is pulled taut and after winding the formers are retracted from opposite ends of said wrapper, two oppositelyv rotatable twist grippers spaced apart from said cylindrical formers for twisting the ends of said wrapper, a conveyor for said pockets, means for intermittently feeding said pockets to the formers, from the formers to the twist grippers and away from the twist grippers, retaining means for preventing lateral displacement of said cylindrical objects in their movements to the formers and while located between said ormers, and means for preventing lateral displacement of said cylindrical objects and for maintaining the wrapper around the cylindrical object while it is fed from the formers to the twist grippers. f

5. A wrapping machine, comprising, in combination, two cylindrical formers concentrically arranged and spaced apart, said formers having a flat portion on their cylindrical surface, grippers opposed to the flat portion on said cylindrical formers for gripping a wrapper to said flat portion, means for rotating said formers for winding said wrapper around said forniers, an open-ended pocket for supporting between said formers and concentric therewithicylindrical objects to be wrapped in said wrapper, means for moving said formers outwardly from each other whereby after being gripped by said grippers the wrapper is pulled taut and after winding the formers are retracted from opposite ends of Asaid wrapper, two opposite y rotatable twist grippers spaced apart from said cylindrical ormers for twisting the ends of said wrappers, means ,for feeding said pockets to the former-s, from the formera to the twist grippers and from the twist grippers, and means for maintaining the wrapper around the cylindrical object while it is fed from the formers to the twist grippers.

6. A wrapping machine, comprising, in combination, two cylindrical formers concentrically arranged and spaced apart, grippers on said cylindrical formers for a wrapper, means for rotating said ormers for winding said wrapper around said ormers, pockets for supporting between said formers and concentric therewith cylindrical objects to be wrapped in said wrapper, means for moving said formers outwardly from each other whereby after being gripped by said grippers the wra per is pulled taut and after winding the ormers are retracted from opposite ends of said wrapper, two oppositely rotatable twist grippers spaced apart from said cylindrical formers for twisting the ends of said wrapper, means for feeding said pockets to the formers, from the formers to the twist grippers and away from the twist grippers, and means for maintaining the wrapper around the cylindrical object while it is fed from the formers to the twist grippers.

7. A Wrapping machine, comprising, in combination, two cylindrical formers concentrically arranged and spaced apart, grippers on said cylindrical formers for a wrapper, means for rotating said formers for winding said wrapper around said ormers, pockets for supporting between said formers and concentric therewith cylindrical objects to be wrapped in said wrapper, means for moving said formers outwardly from each other whereby the formers are retracted from opposite ends of said wrapper, two oppositely rotatable twist grippers spaced apart from said cylindrical formers for twisting the ends of said wrapper, means for feeding said pockets from the formers'to the twist grippers, and means for maintaining the wrapper around the cylindrical object while it is fed from the formers to the twist grippers. A

8. A Wrapping machine, comprising, in combination, two cylindrical formers concentrically arranged and spaced apart, pockets for supporting between said formers and concentric therewith cylindrical objects to be wrapped in said wrapper, said pockets having an inclined wall disposed approximately tangential to the cylindrical formers, grippers on said cylindrical formers adj accnt said inclined wall for a wrapper, means for'rotating said formers and grippers Athereby moving the wrapper down the inclined wall and wrapping it around the formers and cylindrical object, means for moving said formers outwardly from each other whereby after being gripped by said grippers the wrapper is pulled taut and after winding the formers are retracted from opposite ends of said wrapper, two oppositely rotatable twist grippers spaced apart from said cylindrical foi-mers for gathering the ends of said wrappers, means for feeding said pockets to the ltormers, from the formers to the twist grippers and from the twist grippers, and means for maintaining the Wrapper around the cylindrical object while it is fed from the orrnersto the twist grippers. 'ln witness whereof l have hereunto set my hand.

FREDERCK GRGVER.