US2933871A - Wrapping machines - Google Patents

Description

L. BROOK WRAPPING MACHINES Apr-i126, 1960 4 Shgets-S'neet 1 Filed Feb. 15, 1958 April 26, 1960 l.. BROOK 2,933,871

WRAPPING MACHINES Filed Feb. 13, 1958 4 Sheets-Sheet 2 4 Sheets-Sheet 3 Filed Feb. 13, 1958 April 26, 1960 L. BROOK 2,933,871

WRAPPING MACHINES Filed Feb. 13, 1958 4 Sheets-Sheet 4 United States Patent i 2,933,871 WRAPPING MACHINES Leonard Brook, Leeds, England, assignor to The Forgrove Machinery Company Limited, Leeds, England, a company of Great Britain Application February 13, 1958, Serial No. 715,141

` Claims priority, application Great Britain February 175, 1957 4 Claims. (Cl. 53-234) This invention relates to wrapping machines of the type comprising a wrapping wheel arranged to rotate intermittently about a horizontal axis and carrying a number of pairs of article grippers, each of which receives a partially wrapped article at a loading station and carries the articles so received past one or more wrapping stations to a discharge station.

It is the general practice in such machines to fee wrappers in succession into position adjacent to the wrapping wheel by a feed mechanism separate from the wrapping wheel and to lift articles into the article grippers, as they dwell in succession at the loading station, byl an elevator', each article carrying a wrapper with it as it is lifted so that the wrapper is folded in U-forrnation about the article as it enters the grippers.

Recently it has been proposed in my U.S. specification No. 2,784,541 to provide further grippers on the wrapping Wheel which successively feed wrappers from a wrapper feed station remote from the loading station into position above the elevator. This has the advantages (a) that any chippings which may fall from the elevator cannot drop on to the wrapper feed mechanism and (b) that it is no longer necessary to dispose the cutting mechanism `which severs the individual wrappers from a continuous web of wrapping material near the elevator, with the result that the stroke of the elevator can be reduced which is a convenience for high speed running.

In the arrangement described in U.S. specification No. 2,784,541 the wrapper grippers are opened and closed by cam levers external to the wrapping wheel. The present invention has for its object Vto provide an enclosed construction of wrapping wheel which is more easily cleaned and such that it is more difficult for grit and other foreign matter to gain access to the various moving parts associated with the wrapping wheel.

The invention accordingly provides a wrapping machine, comprising a wrapping wheel including a support plate arranged to rotate intermittently on a horizontal axis, a pluralityV of pairs of article `grippers pivotally mounted on the front of the support plate and serving to convey articles in succession from a loading station past one or more wrapping stations to a discharge station, a plurality of pivoted wrapper grippers also mounted on the front of the support plate and serving, as the wheel rotates, to convey wrappers in succession from a wrapper feed station and to presentthem at the loading station in position to be fed by the articles into the article grippers, a cover plateittedto the front of the support plate and cam mechanism and associated cam levers concealed behind the cover plate and operative to control the opening and closing of the article grippers Yand the wrapper grippers. Y

`Conveniently the cam mechanism comprises a cam situated between the support plate and the cover plate Vand mounted for oscillation about the axis of rotation of the wrapping wheel and a pair of cams situated be-y hind the support plate and arranged to be constantly rotated.

Preferably the wrappers are gripped between a single wrapper gripper and the outer face of one of the article grippers, and each wrapper gripper is actuated by an operating lever which applies pressure thereto at a point adjacent the pivot of the article gripper so that actuation of the wrapper gripper imparts little or no turning movement to the article gripper. i'

Two specific embodimentsof wrapping machine according to the invention will now be described in'more detail, by way of example, with reference to the accompanying drawings, in which:

Fig. l is a front elevation of the wrapping wheel of the first embodiment with cover plate removed,

Fig. 2 is a corresponding side elevation of the wrapping wheel, partly in section,

Fig. 3 is a section through the wrapping wheel,

Fig. 4 is a'section on the line X--X in Fig. 3,

Fig. 5 is a section on the line Y-Y in Fig. 1,

Fig. 6 is a front elevation of the wrapping wheel of the second embodiment with the cover plate removed,

and

Figs. 7 and Sare respectively sections on the lines Vil-VII and VIII-VIII in Fig. 6.

Like reference numerals designate like parts throughout the figures.

in the construction shown in Figs. 1`-5, the wrapping Wheel comprises a support plate 10 bolted to a ho1low shaft 11 journalled in the machine frame 12 and receiv# ing intermittent rotation from a Geneva mechanism,not shown. The plate 10 carries the article and wrapper grippers on studs projecting from its front surface and' on the trailing gripper 16 o f each pair meshes with a fur-Y ther quadrant 23 integral with a cam lever 24 pivoted on a stud 31 and carrying a follower 25 coacting with a conical cam 26. Springs 27, 28 urge the vgrippers of each pair towards the closed position. The other gripper 17 of each pair has on its outer face an extension 29 to which is pivoted, also on an axially extending'stud 30,

a wrapper gripper 32 formed with a jaw 33 at its fend whichco-operates with aface 34 on the article gripper -17 to grip the end of a wrapper 36. A spring 35 urgesv the wrapper gripper 32 towards the closed position.

The wheel carries the pairs Vof grippers in succession to the following six equally spaced sations:

Station 1, which is the wrapper feed station. Here a web 37 of wrapping material is fed horizontally towards the wrapping wheel by continuously rotating feed rollers 38. The leading end of the web is fed slightly downwards between guides 39 and, after thewrapper gripper' 32 has closed to `grip it, a continuously rotating knife 40, coacting with a fixed knife 41, severs the gripped wrapper 36 from the web.

Station 2, which is the loading station. Here a wrapper picked up at the preceding station is laid horizontally by the wrapper grippers on top of an apertured feed disc 42 located just below the wrapping wheel. An elevator 43 then rises through the aperture dwelling at the loading station to lift an article 44 from the feed disc into the article jaws, the article carrying the wrapper 36 y I raienfednpr. 26, 1aed its upward travel into, the article jaws 16,: 17 whichV close on it. The wrapper then has two dependingwings projecting from the gripper jaws.

A s the article moves on to stations 3 and 4 the wrapper is further folded in known fashion and at station 5, at the top. of the wheel, the completion of the wrap. is made, for example by twist grippers, not shown. At station4 6 the article jaws are opened and the wrapped article is discharged by any conventional ejector mechanism not shown.,

Associated with' eachy of the wrapper grippers 32 is an` operating lever 46 having a nose 47 which bears against the wrapper gripper 32 at a point opposite the pivot 19 ofthe associated article gripper 17 so that pressure exerted on the wrapper gripper to open it has little or no tendency to rock the article gripper.

The operating lever 46 is mounted on a stud 48. which extends through the plate and carries at, the rear thereof a cam lever 49. A follower 510 on the lever 49 is brought into contact with the appropriate constantly rotating cam 51` or 52 as it reaches station 1 or 2 21S. the case` may be and is maintained in engagement with the cam by a spring 53.

r[he wrapper grippers 32 are normally closed but require to be open at stations 1 and 2 so as to respectively receive and. release a wrapper.

A lobe on the constantly rotating cam 51 or 52 opens the wrapper grippers as they come to rest and further rotation ofthe cam allows the grippers to close again after the wrapper has been fed into or released from the gripper jaws.

The conical cam 26 is arranged to oscillate about the axis of rotation of the wrapping wheel. The cam 26 is disposed in front of the plate 10 and mounted on shaft 5111:l accommodated in the hollow spindle of the Wrapping w eel.

When the wrapping wheel dwells, the follower 25 on the Cam lever 24 associated with the article grippers 16, 17 at the loading station, station 2, is on the high portion of the cam 26 and these article grippers are maintained open. The follower 25 on the cam lever 24 associated with the article grippers at the discharge station, stationV 6,v is however onthe low portion of the cam 26 and this article gripper is still closed. T he conical cam 2,6; is then oscillated to open the article grippers 16, 17 at the discharge station 6 to. release the wrapped article; and slightly later the cam 26 oscillates further in the same direction to the position shown in Fig. l, to allow the article, grippers 16, 17 at the loading station 2 to close. on an article which has by then been brought into position between them by the elevator 43 and top plunger 45. The cam 26 rocks back to its original position as the wrapper wheel rotates.

Axial adjustment` of the conical cam 26 to vary the Opening of the gripper jaws 16, 17 to suit the size of article being wrapped is provided for as follows:

The cam 26 ismounted on a flanged member 55 having an internal thread which` engages with ,an external thread on an adjusting sleeve 56. The sleeve 56 is rotatably mounted on a driving member 57 fixed to the shaft54 and is retained in position by a collar 58 which is fastened rigidly to the driving member 57. A spring dimple 59 in the collar 58 engages holes 60 in the sleeve 56 to lock it in the position of adjustment in relation to. the. driving member 57 correspondingto the cam setting required. Two driving dogs 61 on the flanged member 5,5 engage slots 6 2 in the driving member 57 to provide, the drive to the c am 26. Hand adjustment of the sleeve 56' will cause the conical cam 26 to move axially andv without rotation due to engagement of the driving dogs 6,1 in the slots 62 in the driving member 57.

The construction shown in Figs. 6-8 is generally simi-A 4 lar to. that tust described. In this. case.. however., the article grippers are actuated by the constantly rotating cams and the wrapper grippers are actuated by the oscillating cam.

As shown in Figs. 6 and 7, thel cam lever 24 associated with each pair of article grippers 16, 17 is fixed to its stud 31 and the stud 31 carries, at the rear of the plate 10, an arm 124 onV which is mountedra cam follower 1,25; which Vco-operates with conicall constantly rotating cams 151, 152. The article grippers 16, 17 are normally closed, but as each pair of article grippers reaches Station 2, the loading station, the cam 152 coacts with the follower 125 to open the article grippers as they come to rest. Further rotation of the cam 15,2 thereafter allows the article grippers to close again when an article has been fed into position between them. Similarly, as each pair of article grippers reaches station 6, the discharge station, the cam 151 coacts with the follower 125 to open them and thereafter allows the grippers to close again after the wrappedV article has been discharged from them. Means, not shown, are provided for effecting axial ad-Y justment of ther cams 151, 152 to vary the amount ofopening of the article grippers to suitl the size of the articles being wrapped.

Each of the wrapper grippers 32 is actuated by an operating lever 46 having a nose 47 which bears against the wrapper gripper at a point opposite the pivot 19 of the associated article gripper 17. The lever 46 carrie; a follower 156 which coacts with an oscillating cam 155 mounted on a shaft 54 housed within the hollow shaft 11.

When the wrapping wheel dwells, the follower of the cam lever 46 vof the Wrapper gripper 32 at the wrapper feed station, station 1, is on the high portion of the cam and this wrapper gripper is maintained open, while the follower of the cam lever of the wrapper gripper at the loading station, station 2, is on the low portion of the cam and this wrapper gripper is closed. After a wrapper has been fed into the wrapper gripper at station 1 the cam 155 oscillates to open the wrapper jaws at station 2 to release the wrapper which has by then been nipped between the top plunger and the article on the elevator. Slightly later the cam 155 is oscillated further in the same direction to close the wrapper jaws at station 1. During the movement of the wrapper grippers fromV station 1 to station 2 the cam 155 rocks backl to its previous position.

In both of the constructions illustrated the wrapping wheel is of enclosed construction, the cams being con cealed by thecover plate 13, with the oscillating cam in front of and the rotating cams behind the support plate 10. The moving parts associated with the wrapping wheel are thus protected from grit and other foreign matter but may easily be cleaned on removal of the cover plate.

What I claim as my invention and desire to secure by Letters Patent is:

1. In a wrapping'machine a wrapping wheel including a support plate arranged to rotate intermittently on a horizontal axis, a plurality of pairs of article grippers pivotally mounted on the front of the support plate and' serving to convey articles in succession from a loading station past one or more wrapping stations to a discharge station, a plurality of single wrapper grippers, which are respectively pivotally mounted on one of each pair of article grippers, each Wrapper gripper coacting with said article gripper to convey wrappers in successionA from a wrapper feed station and to present them at the loading station in position to be, f ed'byy the articles into the article grippers, springs associated with each pairV of article grippers and no rmallyv urging saidV grippers to closed position, a spring associated with each wrapper gripper and normally yurging it to engage the article gripper to which it is pivoted, control linkages associated with the article and wrapper grippers, and cam mechanism operative on said linkages, while the wrapping wheel is dwelling to open the article grippers at the loading and discharge stations and thereafter permit them to close and to open the wrapper grippers at the wrapper feed and discharge stations and thereafter permit them to close, said cam mechanism being adjustable to vary the opening movement imparted to said article grippers.

2. In a wrapping machine, a wrapping'wheel comprisa horizontal axis and carrying a plurality of gripper assemblies spaced uniformly around its periphery, each gripper assembly including a pair of article grippers pivoted to the support plate and serving to convey articles in succession from a loading station past one or more wrapping stations to a discharge station and a wrapper gripper pivoted to` one of said article grippers and co.

ing a support plate arranged to' rotate intermittently on 6 closing of the article grippers and the wrapper grippers, said'cam mechanism being adjustable to vary the opening movement imparted to the article grippers.

3. In a ,wrapping machine, a wrapping wheel as claimed in claim 2, wherein each wrapper gripper is urged by a spring to close against the article gripper to which it is pivoted and wherein the cam lever for actuating the wrapper gripper applies pressure thereto at a point adjacent the pivot of said article gripper.

4. In a wrapping machine, a wrapping wheel as claimed in claim 3, wherein each wrapper gripper is pivoted on a lateral extension at the outer side of the article gripper and coacts with the end of the article gripper togrip. and feed wrappers. l

References CitedV in the file of this patent UNITED STATES PATENTS Edis et al Mar. 12, 1957

Images