US1902079A

US1902079A - Box wrapping machine

Info

Publication number: US1902079A
Application number: US513984A
Authority: US
Inventors: Arthur E Johnson
Original assignee: WM Wrigley Jr Co
Current assignee: WM Wrigley Jr Co
Priority date: 1931-02-06
Filing date: 1931-02-06
Publication date: 1933-03-21
Anticipated expiration: 1950-03-21

Description

March 21, 1933; A. E. JOHNSON 1,902,079

BOX WRAPPING MACHINE v Filed Feb. 6, 1931 4 Sheets-Sheet l *1 H c9 m: 11 ii iEMFIWQ Y! ooookk g N gg oooooo 5 000000 i. V) Q! E QQ omog b00000 n I 0 on I PO 0 March 21, 1933. A. E. JOHNSON 1,902,079

BOX WRAPPING MACHINE Filed Feb. 6, 1931 4 Sheets-Sheet 2 WW5; W MUM; f

March 21, 1933. A. E. JOHNSON BOX WRAPPINC- MACHINE.

Filed Feb. 1931 4 Sheets-Sheet 3 Id J70 Z650 66. lgw

March 21, 1933. o sb 1,902,079

BOX WRAPPING- MACHINE Filed Feb. 6, 1931 4 Sheets-Sheet 4 4 a 116 16g 2 '9 42M 26 26%? 1 2 'GiDI IHIIHIifii 27 l-lll it AF W @E 4 m Patented Mar. 21, 1933 PATENT OFFICE ARTHUR E. JOHNSON, OF OAK PARK, ILLINOIS, ASSIGNOR TO WM. WBIGLEY JR.

COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE BOX WRAPPING MACHINE Application filed February This invention relates to improvements in box wrapping machines, and more particularly to machines for applylng covering sheets to the outer surface of cardboard 5 boxes.

The chief object of the invention 1s to provide mechanism for transferring the boxes from the feed belt into the path of the sheet applying mechanism, a step in the operation of these machines which heretofore was a manual operation.

More specifically, the ob ect of the invention is to improve upon a previously disclosed mechanism for the same purpose previously disclosed in application for Letters Patent filed by Herbert J. Melville on May 26, 1930, Serial No. 455,621.

A brief discussion ofthe operation performed by machines of this type generally and the improved mechanism, will precede the detailed disclosure of the subject matter:

The operation performed is that of applying acoating of paper to the exterior of an open box or box cover. A conveyor belt transports the adhesive coated sheets of paper towarda station heretofore occupled by an operator who centered a box on each sheet, and in the same operation transferred the same with the sheet adhering to its bottom 33 into the path of a vertically moving plunger,

which carried the assembled parts into contact with a series of brush wipers whereby the sheet was wiped against the outside and inside of the box and then discharged. In such 35 an organization it is manifest that the output of the machine is determined by the limit of the ability of a skilled operator to continuously assemble and transfer the boxes from one part of the machine to the other,

and, therefore, to eliminate the human factor and replace it by mechanical means for performing the same work, insures increased production and a superior product.

As already suggested, the transition from a wrapping machine partially manual in operation to one entirely automatic except for the assembling of the boxes and cover sheets on the conveyor, constituted the subject matter of said prior application, but as will later 5 be pointed out, the present type of transfer 6, 1931. Serial No. 513.984.

mechanism is believed to be and serviceable.

For the purpose of this disclosure, it will not be necessary to illustrate the complete machine, inasmuch as the improved mechanism consists of parts which function to transfer the box and its cover from the feed belt to the applying mechanismfboth of which may be considered as common to machines now in use.

Referring, therefore, drawings,

Figure 1 is a top plan view of theimproved transfer mechanism and adjacent portions of a box coating machine, as taken on line 11 of Figure 2. A

Figure '2- is a view in side elevation of the transfer mechanism and adjacent parts as taken on line 22 of Figure 1.

Figure 3 is a perspective view of the transfer mechanism and an assembled box about to be transferred. I

Figure 4 is an enlarged detail view in vertical section taken on line 44 of Figure 1, shgwing the transfer carriage about to engage a ox.

F igure 5 is a View similar to Figure 4', showing the same parts at the completion of the transfer movement; and

Figure 6 is a detail view in vertical section taken on line 66 of Figure 5.

Considering the machine as a whole, the essential parts are the feed belt 1, and the wrapper applying mechanism including a vertically reciprocating plunger assembly 2 of the feed belt near located on one (left) side its discharge end. The feed belt is an endless web having a travel of, say, 15 or 20 feet in a horizontal direction at table height, being supported at either end on pulleys 3, the upper lead being the active portion of the belt moving continuously toward its discharge end. The belt is perforated, and between the two leads is a shallow box or duct 4 having its top wall 4a; perforated and its interior, otherwise sealed, connected with a suitable exhausting apparatus for maintaining an internal pressure of less than atmospheric pressure. The duct 4 extends substantially throughout the length of the belt, with its perforated top more practical to the accompanying wall section terminating just short of its discharge end. The upper lead of the belt travels in contact with the perforated top wall of the duct and the suction acts to hold the covering sheets in contact with the belt until they are carried beyond the perforated area of the top wall and then freed to be removed or transferred therefrom. As shown in Figure 3, the boxes A to be covered are relatively shallowand made of any suitable stock. The wrapping or coating sheets B of suitable paper stock are cut to the size of the boxes, having a central panel of the same dimensions as the bottom of the box and marginal flaps 6 formed by cutting rectangular sections from the corners. These flaps are slightly wider than the upright walls a of the box A and eventually are folded against the same, the excess width being carried over the edges and downwardly agamst the inner surfaces of these walls. The sheets B are fed onto the belt 1 at the outer or head end thereof, having previously had their upper surfaces coated with glue.

As the cover sheets travel forwardly in regular and spaced order, an operator places or spots a box A centrally of each sheet, so that they reach the end of their travel in the r partially assembled condition shown in Figure 3, namely, with the flaps 6 extending outwardly and flat upon the belt.

Now the transfer mechanism is located above the dischar e end of the belt and opposite the vertical pl unger assembly 2, and consists in general of a horizontally reciprocating carriage equipped with grippers, whereby each box on reaching a position in front of the retracted carriage is picked up with its cover sheet adhering to its bottom and quickly transported laterally into the path of a vertically reciprocating plunger head 2a secured to the lower end of a plunger rod 212 which at that instant is descending, whereupon the box is stripped from the carriage which then returns to its starting position for the next, box, and so on.

For the reasons already stated, it is not necessary to go into detail as to the manner in which the cover sheets are folded and applied to the boxes after they are deposited in the path of the descending plunger head 26. Suffice it to say that the plunger enters the box and carries it downwardly into contact with rows of brush-like wipers 5, which fold and smoothly apply the glued surfaces of the flaps 6 against the sides and ends of the box walls. YVhen the plunger reaches the lower end of its stroke, the same or other sets of wipers operate to fold the margins of the flaps over and inside the box walls, whereupon the plunger moves upwardly carrying the completed box which is then removed by cam actuated stripper fingers 6 projecting through openings in the plunger head 2a, whereupon it is removed from the machine by a reciproeating push rod 7 which bunts the finished boxes out of the path of the plunger.

The transfer mechanism comprises in general a slidin carriage 8 mounted on a track consisting o a pair'of

parallel round rods

9, 9 extending transversely of the belt just above and short of the box take-off end and opposite the plunger 2. These rods are supported at their inner and outer ends by

rackets

10 and 11 respectively, the former depending from an upper part of the machine frame adjacent the plunger shaft :27 and the latter fixed to the lower part of the frame and projecting outwardly and upwardly beyond the outer edge of the belt 1. As shown clearly in Figure 2, the

track rods

9, 9 are inclined upwardly at a slight angle from the belt 1 toward the plunger 2.

Referring now to the carriage 8, the same is in the nature of a cross head sliding on the

rods

9, 9 and carrying a pair of grippers at its forward edge. The carriage consists of a body casting 12 extending transversely beneath the rods with a pair of integral bosse. at its upper edge which are bored to slide on the

rods

9, 9. Extending rearwardly from the body casting in line with one of the rods is an integral arm 13 having a sleeve 13a at its end sliding on the rod above, thereby providing a three point support for the carriage on the track.

Mounted ahead of the frame 12 is an integral pusher bar 14 supported by transverse webs 14a. Above the pusher bar and slightly to the rear thereof is a transverse rock shaft 15 journalled near its ends in bearing sleeves 15a, 15a cast integral with the frame 12 of the carriage, and just inwardly from the hearing sleeves are mounted a pair of bloc-

ks

16,16 to which are fixed the gripper fingers 16a, 1611. At the rear end of the rock shaft 15 is a fixed cam lever 17 having a roller 1711 at its end, the same adapted to coact with the cam 18 in the form of a flat bar extending horizontally beneath it. This cam is supported at one end upon the bracket 11 and curving upwardly and inwardly, extends transversely above the belt surface and beneath the cam lever 17. The forward end of the cam bar is curved downwardly to provide an incline 18a located at the point in the travel of the carriage at which the boxes are picked up by the grippers, as will be presently described.

At the forward end of the rock shaft 15 is a guide finger 19 somewhat longer than the gripper fingers 16a and consisting of a metal bar secured to the block 16 of the adjacent gripper finger and extending forwardly and thence downwardly, terminating in a somewhat pointed end formed by cutting the in Her edgeof the bar along a curved or beveled line as shown at 19a (Figure 6).

The rock shaft 15 with the gripper fingers 16a, 16a, cam lever 17 and guide finger 19 fixed thereto, form a unit adapted to swing through anarcof less than 90, -namely,

through the angle between theelevated and lowered positions of the gripper fingers 16a as shown in. Figures .4 and 5. A coil spr ng 20 acts on therock shaft to swing it in a counterclockwisedirection'and to oppose the cam action which swings it in the opposite direction. Thi spring is secured at one end to Y oneof the blocks'l6 on the shaft and is aner bar 13 strikes the wall of the boxA about to] be transferred from the belt' l to the plunger mechanism, thereby permitting the gripper fingers 16a to swing down inside of thebox and clamp the edgeof the wall against the pusher bar 14;, whereby the box is shifted laterallyand at the same time is lifted from the surface of the belt'due'to the inclination of the

rods

9, 9 as shownin Figure 5. The boxes A with the coversheets adhering to their bottoms, are fed in rapid succession so that after each box is delivered into the path of the plunger head and stripped from the grippers, it returns for the next one -whlch is brought to rest by astep bar 21 mounted in its path in the position to be picked up by the grippers, the proper positioning being insured by the guide finger 19 at the end of the carriage, its beveled inner edge acting to shift the boxes against the stop bar-just in advance of the gripping action, should the same be slightly out of position.

The drive for the sliding carriage 8 consists-of a pair of

parallel levers

22 and 23 connected by a transverse rod 24, the first and shorter lever being actuated by a plate cam 25, and the latter lever being driven and connected with the transfer carriage 8 by a link 26 and a short arm 27 extending laterallyv from the carriage frame toward the lever 23, and having pivotal connection at its end with the connecting link 26. To avoid a rigid connection at the carriage, the arm 27 is pivotally connected to the top of the frame 12 by a pivot pin 26a at a short distance from its end (Figure 6), and a stifif coil spring 28 is attached to the arm at its end and is anchored to the frame 12 just forwardly thereof. Thus in case the carriage for any reason should suddenly be obstructed, the shock would be taken up and absorbed by the swinging of the arm 27 and thus avoid possible breakage. I

Now as shown in Figures 1 and 2, the main frame of the machine has a supporting base 30 of about table height, and extending up wardly from its surface is a post or standard carria 31 supporting amongfother parts, the reciprocating plunger mechanism 2. On either side'of this post and near opposite corners of the base 30 are

brackets

32 and 33 which support the parallel lever arms '22 and 23 re.-

s'pectively. p I I The bracket 33 supporting the longer lever v23 is located beyond the end of the conveyor belt 1- and the axis of the'bearing proper upon which the lever arm is mounted, is inclined slightly to the vertical so that the lever arm swings in a plane parallel with the plane of the carria e tracks 9, 9 and not in a horizontal plane. he shorter lever arm 32, on the other hand, does swing about a vertical axis, and to compensate for the parallel movement in slightly oblique planes, the con- .necting rod 24 is provided with

end fittings

24a, 24a of the universal joint or swivel type so that the rod is free to oscillate slightly in avertical plane as it moves endwise. The connecting rodalso is attached at the end of the short lever 22, and with the longer lever approximately midway of its length, and since the latter is about twice the length of the former, it follows that the are through which the outer end of the long lever travels is considerably greater than that of the short lever, a matter of ratio which is only important in designing the driving mechanism for the e, including the cam 25 operating the short lever. This cam is mounted on a vertical shaft 34 adjacent the short lever 22, and is preferably of the plate or disc type having a groove 34a. of predetermined contour in which rides a cam roller 22a journalled midway the ends of the lever 22.

Now the cam groove is shaped to transmit a definite movement to the lever 22 acting as a cam follower, this movement being transmitted to the long lever, and thence to the carriage through the link 26.

Without going into detail as to the shape of the cam, it may be stated that the movement sought is primarily a reciprocating motion which is timed to the vertically reciprocating movement of the plunger so that a box is placed beneath the descending plunger head at the proper instant. Bearing in mind that the plunger moves quite rapidly and that there is but a short interval of time allowed for thrusting the box into its path, a uniform reciprocating movement is neither desirable nor satisfactory, inasmuch as it means rapid strokes, quick reversals and abrupt gripping and displacement of the boxes,a motion which places undue strain on the transfer mechanism. As a matter of fact, this is the objection to the drive disclosed in the prior application referred to.

With the present drive mechanism, a variable reciprocating movement is imparted to the carriage, which may be described as generally uniform, except as the carriage approaches the end of its stroke toward the veran exceptionally rapid return stroke as would.

bethe case if the carriage or any part thereof had to clear the plun er. Hence the return movement while rapi is moderate as com- .pared with the quick short thrust that takes place at the end of the forward or feeding stroke, the thrust being so short in fact that there is no increase .of inertia, and hence no added strain in bringing the carriage to rest and starting it on its return stroke.

In short, by the arrangement of the levers and cam drive, herein disclosed, it is possible to obtain greater efficiency in the operation of the machine, both from the standpoint of production and maintenance, since it eliminates excessive wear on the transfer mechanism by varying its speed throughout different portions of its stroke, but without reducing or otherwise interfering with the timing of the machine as a whole. I

Having set forth a preferred embodiment of my invention, I claim:

1. In a box wrapping machine, the combination of feeding means upon which the boxes and cover sheets are assembled, sheet applying mechanism adjacent said feeding means including a plunger, a box transfer member movable between said feeding means and the path of said plunger, and means for driving said transfer member comprising a lever arm connected at its free end with said transfer member, another arm parallel with said first lever arm, a connecting rod between s'aid lever arms and driving means for imparting a predetermined oscillatory movement to said last mentioned lever arm.

2. In a box wrapping machine, the combination of a feed belt upon which the covering sheets and boxes are assembled, sheet applying mechanism adjacent said feed belt and including a vertically reciprocating plunger, a transfer member operative to transfer the boxes from said feed belt into the path of said plunger, and means for imparting a predetermined movement to said transfer member comprising a driving and a driven lever connected to swing in substantially parallel relation, said driven lever having operative connection at its end with said transfer member, and a cam acting on said driving lever for imparting a predetermined oscillating movement thereto.

3. In a box wrapping machine, the combination of feeding means upon which the covering sheets and boxes are initially assembled, sheet applying mechanism ad acent said feeding means including a reciprocating plunger, a reciprocating carriage operative to transfer assembled boxes and sheets from said feeding means into the path of said plunger, and means for imparting a predetermined movement to said carriage comprising parallel driving and driven levers, a rod connecting the end of said driving with said driven lever intermediate its ends and the latter having operative connection at its end said belt into the path of saidplunger, and

means for impartin a predetermined movement to said trans er member comprising a relatively long leverarm pivotally connected at its free end with said carriage, a shorter lever arm spaced from said first lever arm, a connecting rod joining the free end of said shorter lever arm with the longer lever arm lntermediate its ends, and means for imparting a predetermined oscillating movement to said shorter lever arm.

5. In a box wrapping machine, the combination of a horizontal feed belt upon which the boxes and wrapping sheets are assembled and advanced toward a predetermined transfer station, sheet applying mechanism including a vertically reciprocating plunger adjacent said feed belt, a reciprocating carriage operative to transfer said assembled boxes from said belt along an upwardly in-. clined path into the path of said plunger, and means for imparting a predetermined movement to said transfer member comprising a relatively long lever arm pivotally connected with said transfer member, a shorter lever arm parallel with said first lever arm, a connecting rod having swivel connections with the free end of said'shorter lever arm and withvthe longer lever arm intermediate itsends and a rotative driving cam operatively connected with said shorter lever arm.

6. In a box wrapping machine, thecombination of a feed belt upon which the boxes and wrapping sheets are assembled and advanced toward a station adjacent sheet applying mechanism including a vertically reciprocating plunger adjacent said feed belt, a transfer member operative to lift said assembled boxes from said belt and transport them'into the path of said plunger, inclined guides supporting said transfer member, and means for imparting a reciprocating movement to said transfer member comprising a relatively long lever arm pivotally mounted at one end and connected at its other end with said transfer member, a relatively short lever spaced from said longer lever and pivotally mounted at one end, a connecting rod connecting said levers in parallel relation a and having swivel connections at its ends with the end of the shorter lever and with the longer lever substantially midway of its ends,

and a positively driven cam for driving said shorter lever.

Signed at Chicago, 111., this 4th day of February 1931.

ARTHUR E. JOHNSON.