US3306003A

US3306003A - Package wrapping machine

Info

Publication number: US3306003A
Application number: US270391A
Authority: US
Inventors: William E Sundy; Daniel H Hickok
Original assignee: WO Hickok Manufacturing Co
Current assignee: WO Hickok Manufacturing Co
Priority date: 1963-04-03
Filing date: 1963-04-03
Publication date: 1967-02-28
Anticipated expiration: 1984-02-28

Description

Feb, 28, 1%? w. E. SUNDY ETAL PACKAGE WRAPPING MACHINE l0 Sheets-Sheet 1 Filed April 5, 1963 INVENTORS WILLIAM E. SUNDY BY DANIEL H. HICKO K 24M ATTOR NEY Feb. 28, 1967 w. su T 3,306,003

PACKAGE WRAPPING MACHINE Filed April 5, 1963 10 Sheets-Sheet 3 l BY & WILLIAM E. SUNDY y"; HilggK O N I 9 w. E. SUNDY ETAL 3,396,003

PACKAGE WRAPPING MACHINE 10 Sheets-Sheet 4 Filed April 5, 1963 o o i 8 m7 5 m f 3 1 m 0 r0 m 7 B Q m w O F M INVENTORS WILL'AM E. SUN DY DA IEL H. CKOK ATTORNEY Feb. 28, 1967 w. E. SUNDY ETAL 3,306,003

PACKAGE WRAPPING MACHINE Filed April 5, 1963 10 Sheets-Sheet 5 IN VENTORS WILLIAM E. SUNDY BY DANIEL H. HICKQK ATTORNEY Feb. 28, 1967 w. E. SUNDY ETAL 3,306,003

PACKAGE WRAPPING MACHINE Filed April 5, 1963 10 Sheets-Sheet 6 IN VEN TO S WILLIAM E. SUNDY BY DANIEL H. HICKOK WK LP ATTORNEY Feb. 28, 1967 w. E. SUNDY ETAL PACKAGE WRAPPING MACHINE l0 Sheets-Sheet 7 Filed April 5, 1963 INVENTORS WILLIAM E. SUNDY ATTORNEY Feb 28,- 1967 w. E. SUNDY ETAL PACKAGE WRAPPING MACHINE l0 Sheets-Sheet 8 Filed April 5, 1963 INVENTORS WILLIAM E. SUNDY ANIEL H HICKQK ATTORNEY Feb. 28, 1967 w. E. SUNDY ETAL PACKAGE WRAPPING MACHINE l0 Sheets-Sheet 9 Filed April 5, 1963 INVENTORS WILLIAM E. SUNDY Y W O R m w H I T A N A o Y B Feb. 28, 1967 w. E. SUNDY ETAL 3,306,003

PACKAGE WRAPPING MACHINE Filed April 5, 1963 10 Sheets-Sheet l0 INVENTORS WILLIAM E. SUNDY BY DANIEL H. HIC 0K ATTORNEY United States Patent 3,306,003 PACKAGE WRAPPING MACHINE William E. Sundy, New Cumberland, and Daniel H. Hickok, Linglestown, Pa., assignors to The W. 0. Hickok Manufacturing Company, Harrisburg, Pa., a corporation of Pennsylvania Filed Apr. 3, 1963, Ser. No. 270,391 9 Claims. (Cl. 53228) This invention relates to a package wrapping machine.

It is the common practice in wrapping packages with sheet material, for example, polyethylene sheets, to cut a sheet to be wrapped around a package and perform the sheet folding steps along the sides of the package longitudinally of a conveyor as the latter moves over the conveyor. The package is thus wrapped with the sheet of material therearound transversely to the direction of movement along the conveyor, and the article or package is then moved over a different conveyor at right angles to the first-named conveyor to fold the sheet and seal it with respect to the ends of the package, which are now parallel to the direction of movement.

An important object of the present invention is to provide an apparatus for wrapping articles or packages wherein the ends thereof, which ordinarily are wrapped by changing their direction of movement as referred to above, can be closed with the sheet of material as the first step in the operation, while the article or package is moving in the direction perpendicular to the planes of the ends of the article or package.

A further object is to provide such an apparatus wherein the wrapping sheet, for example, heat-scalable polyethylene or any well-known pressure-sealable material, is cut to a predetermined length and moved into the plane of movement of the article and to engage the sheet with the article intermediate the ends of the sheet whereby the leading end of the article engages the sheet and pushes it along so that sidesof the sheet contact with the tops and bottoms of the packages, and then, while the article is still moving, to effect the folding of the sheet over the following end of the package, after which conventional means may be employed for closing the sheet around the sides of the package or article with the latter continuously moving.

A further object is to provide such an apparatus wherein the length of the sheet of wrapping material is such that the extremity of the sheet at the bottom of the package, after the latter is pushed through the plane of the pre-cut sheet, is coincident with the plane of the following end of the article while the other end of the sheet extends downwardly over the following end with an extended flap, and to provide means for tucking such flap beneath the package and sealing the flap in closed position.

A further object is to provide a method and apparatus of the character just referred to wherein the tucking operation is accomplished by an element movable at a speed greater than the speed of movement of the package over the conveyor, thus eliminating any stopping of the conveyor or any changing of the direction of movement of the package.

Other objects and advantages of the invention will become apparent during the course of the following description.

In the drawings I have shown one embodiment of the invention. In this showing FIGURE 1 is a side elevation of the apparatus, a portion of the supporting frame being broken away;

3,300,003 Patented Feb. 28, 1967 FIGURE 2 is an enlarged fragmentary side elevation looking from the opposite side of the apparatus showing a portion of the drive means;

FIGURE 3 is a plan view of the apparatus, end portions being broken away, and parts being removed;

FIGURE 4 is an enlarged fragmentary sectional view on line 44 of FIGURE 3;

FIGURE 5 is a transverse vertical sectional view on line 5-5 of FIGURE 4;

FIGURE 6 is a fragmentary longitudinal sectional view on line 66 of FIGURE 3;

FIGURE 7 is a fragmentary transverse vertical sectiona1 view on line 77 of FIGURE 6;

FIGURE 8 is a schematic-sectional view taken substantially on the same plane as FIGURE 4, parts being omitted, showing an initial stage of the wrapping operaion;

FIGURE 9 is a similar view showing the next step in the sequential operation;

FIGURE 10 is a similar view showing the next stage of such sequential operation;

FIGURE 11 is a schematic-structural view of portions of the apparatus, parts being omitted, taken on the same plane as FIGURE 4; and

FIGURE 12 is a detail sectional view on line 1212 of FIGURE 11.

Referring to the drawings, the numeral 10 designates the main frame as a whole having an upper elongated horizontal supporting structure 11 and supporting legs 12. The upper supporting structure 11 carries horizontal side frame members 13 projecting toward the left or inlet end of the machine.

Referring to FIGURES 3, 6 and 7, the frame members 13 are connected by transverse supports 15 over the tops of which are arranged a pair of horizontal cam trackways 16, the inlet ends of which are curved arcuately as at 17 for a purpose to be described.

Above opposite sides of the inlet end of the machine is arranged a pair of plates 20, the left-hand ends of which in FIGURE 1 are supported on a cross bar 21 fixed at its ends to the side frame members 13. Such cross bar similarly supports the adjacent end of a central longitudinal plate 22, the longitudinal edges of which are spaced from the inner edges of the plates 20 for a purpose to be described. The opposite end of the plate 22 (FIGURE 6) may be supported in any suitable manner, for example, by brackets 23 carried by a transverse member 24 secured to the side frame members 11.

The plates 20 support side guides 26 and are connected thereto by brackets 27 adjustable with respect to the plates 20 by wing nuts 28 engageable in selected threaded openings 29, according to the width of the'packages to be fed between the guides (see FIGURE 3).

Associated with each cam trackway 16 is a conveyor chain 32 passing around

sprockets

33 and 34, respectively. Each of the sprockets 34 is carried by a stub shaft 35, the space between the sprockets 34 being clear for a purpose to be described. The sprockets 33 are carried by a drive shaft 37 extending from one side of the apparatus to be driven by means to be described. Each of the chains 32 carries a plurality of pushers 38 pivotally connected to links thereof as at 39. Each pusher 38 is provided with a long arm 40 and a relatively short arm 41. It will be noted that the arcuate sections 17 of the cam trackways 16 are eccentric to the shaft 37, the lower portions of the arcuate cam trackway sections being closer to the axis of the shaft 37 than the top portions of the arcuate sections.

Referring to FIGURE 6, it will be apparent that with the

sprockets

33 and 34 rotating clockwise, the short arms of the pushers 38 will engage the arcuate camway portions 17 as the chains move around the sprockets 33, and in the top runs of the chains, the long arms 40 will be held in vertical position to move to the right successive packages 44 shown in broken lines in FIGURE 6. As each pair of pushers 38 reaches the right-hand end of the horizontal cam trackway 16, the short arms 41 of the pushers will be released to swing to inoperative positions as shown in FIGURES 4 and 6, whereupon each. successive package will be engaged by a separate conveyor. The purpose of the swinging of the pushers 38 as described will become apparent below.

As further described below, the present machine is intended to operate to close the ends of a continuously moving package, which ends extends transversely of the direction of movement of the package. The machine is primarily intended to use polyethylene plastic sheets, or similar material, as the covering for the packages, and to this end, a roll 50 of the material is supported in any suitable manner above the inlet end of the apparatus. The web 51 on the roll 50 is fed between a pair of pinch rolls 52 and then downwardly over a rotary cutter 53 (FIGURE 4). The pinch rolls 52 and rotary cutter 53 form no part of the present invention and may be driven by any suitable means.

From the rotary cutter 53, the web moves downwardly over a vertical stationary plate 54 suitably supported on the apparatus, and endless belts 55, passing over pulleys 56 with their runs adjacent the plate 54 engageable with the web of the sheet, feed it downwardly to a predetermined point below the plane of movement of the packages through the apparatus. Such distance of movement of the Web is predetermined in accordance with the wraparound length of material necessary for a given package, as further described below. The rotary cutter 53 is so timed that it will sever the web when the lower end thereof reaches the predetermined point necessary to provide a wrapper of required length. The vertical plate 54 may be supported in any suitable manner, for example, by standards 58, and form part of the unit for supplying separate web sections to the machine in a position to be utilized in accordance with the present invention.

In the next succeeding section of the apapratus, a plurality of spaced parallel plates 60 extend longitudinally in the direction of movement of the package, and between adjacent pairs of such plates are arranged conveyor belts 61 traveling over

pulleys

62 and 63 mounted respectively on

shafts

64 and 65, the latter of which has an end 66 projecting beyond the apparatus for the connection of drive means thereto as described below. The plates 60 are secured as at 67 to a transverse plate 68 having its ends mounted on the side frames of the apparatus. The plates 60 form a support for the package which is propelled by the endless belts 61 through the section of the mechanism being described.

Packages traveling over the belts 61, as described be low, will have the polyethylene wrapper in the process of being applied thereto and an overhead endless belt '70 engages the wrapper to maintain it in snug engagement with the top of the package. The lower run of the belt 70 is parallel to and moves at the same linear speed as the upper runs of the belts 61. Firm contact of the lower run of the belt 70 with the wrapper of the package is maintained by running the lower run of the belt 70 over rollers 71 carried by arms 72 spring-biased as at 73 to tend to swing the rollers 71 downwardly. The arms 72 are pivoted as at 74 to side bars 75. Adjacent the inlet end of the apparatus a plate 77 is pivoted as at 78 to the side bars 75 (see FIGURE 4) and carries a plurality of rollers 79 about which the belt 70* passes. Intermediate the ends of the wrapper section of the machine now being considered, the upper run of the belt 70 passes around an upper idler pulley 80 supported as at 81. At the other end of 4 the wrapper section, the lower run of the belt passes around the righ-hand end roller 71 (FIGURE 1), thence upwardly around a drive pulley 82, and thence upwardly over the pulley 80. The drive pulley or roller 82 is mounted on a shaft 83 driven in a manner to be described.

Beyond the ends of the conveyor comprising the belts 61 and longitudinally spaced therefrom is a conveyor belt 88 associated with means (not shown) and forming no part of the present invention for folding and sealing the wrapper along the sides of the article parallel to the direcion of movement thereof. Such means may be of any desired type and is now conventional. The belt 88 passes around the rollers 89 and 90 mounted respectively on

shafts

91 and 92 carried by side bars 93 supported in any suitable manner with respect to the supporting frame of the apparatus. The shaft 91 is provided at one end with a sprocket 95, the driving means for which has been omitted from FIGURE 3 in the interest of clarity of disclosure.

As the article or package passes from the conveyor belts 61 to the conveyor belt 88, the following end of the article projects toward the inlet end of the machine relative to the roller 89. Such projecting end of the article is supported at times by a roller mounted on the upper ends of arms 101. The lower ends of the arms 101 (FIGURES 4, 5, 11 and 12) carry vertically slidable members 102 mounted for vertical movement in guides 103 carried by plates 104 (FIGURES 11 and 12). Below the guides 103 the members 102 carry follower rollers 105, each of which engages a cam generally indicated at 106, such cams being mounted on a transverse shaft 107 driven in a manner to be described. The lower ends of the members 102 (FIGURES l1 and 12) slide in guides 110. The lower end of each member 102 is welded to a plate 111 and such plate is bonded to a rubber or other resilient body 112, having a similar plate 113 bonded to the bottom thereof and connected to the upper end of a spring 114. Each spring 114 projects through an opening 115 in a plate 116. The lower ends of the springs 114 are connected as at 117 to a lower transverse plate 118 supported from the side frame members 11 (FIGURES 4 and 5).

Each cam 106 is provided with a semi-circular portion 120 engaging the associated follower roller 105, and during the period of engagement of the follower rollers 105 with the concentric cam portions 120, the roller 100 will have its top in the plane of the upper runs of the

conveyor belts

61 and 88. Each cam 106 rotates in a clockwise direction as indicated by the arrow in FIGURE 11, and at the proper point, each roller drops oif a shoulder 121 and the follower roller 105 then comes in contact with the dwell portion 122 of the associated cam. At the end of the dwell portion 122, each cam is provided with a rise 123 and engagement of such portion with the roller 105 elevates the latter to the position shown in FIGURES 8 and 11. When each follower roller 105 drops off its shoulder 121, the plate 113 associated with each member 102 engages the adjacent plate 116, and the resilient body 112 acts as a shock absorber.

As previously stated, as the article moves through the plane of the sheet, the sheet intermediate its ends will be looped around the leading edge of the article as at (FIGURE 4) and the sheet will extend along the top and bottom of the article as at 131 and 132, respectively. The end of the bottom section 132 of the sheet will terminate approximately in the plane of the following edge of the article, while the end of the sheet portion 131 extends downwardly as a flap 133, the size of which will be greater than the thickness of the article to leave at the bottom thereof a loose flap end 134 (FIGURE 9). Also as previously stated, after leaving the conveyor belts 61, the following end of the article projects substantially beyond the roller 89 toward the inlet end of the machine as shown in FIGURES 8 and 9. Until later operations take place, the overhanging end of the article is supported by the roller 100 as shown in FIGURE 8.

To insure downward movement of the flap 133 over the end of the article, pairs of aligned fingers 138 move downwardly over the flap 133 as shown in FIGURES 3 and 8 to insure the folding of the flap 133 over the end of the package or article. The space between these fingers is provided so that the fingers will pass the holddown belt at the center of the machine as close to the belt as practicable. Incidentally, it may be noted that this hold-down belt and associated elements have been eliminated from FIGURE 3 for the purpose of illustration, but have been shown in FIGURES 1, 2, 4 and 5. Three pairs of the fingers 138 are shown in the present embodiment of the invention, these fingers being carried by links 139 of chains 140. The chains 140 pass around

sprockets

141 and 142 mounted and freely rotatable on the

respective shafts

64 and 65. These chains also pass around

lower sprockets

143 and 144 and around

upper sprockets

145 and 146. The

various sprockets

141, 142, 143, 145 and 146 are supported on suitable shafts. For example, the sprockets 143 are mounted on a suitably supported shaft 150. The

sprockets

141 and 142 are supported on the

shafts

64 and 65 previously described. The

sprockets

145 and 146 are respectively supported on

stub shafts

151 and 152, and these shafts at opposite sides of the machine are supported by bearing brackets 153 mounted on the main supporting frame. It will become apparent that the chains 140 are driven in timed relation to movement of the article onto the conveyor 88 so that when the following end of each article reaches the proper position, a set of the fingers 138 will move downwardly to insure the proper folding of the flap 133.

After a set of the fingers 138 has moved beyond the bottom of the article, the flap end is tucked under the article by means of a transverse tucker plate 158 carried by arms 159. These arms extend beneath the tops of the conveyor belts 61 and plates 60 and over the shaft 65, then downwardly as at 160 to terminate in a horizontal end 161 each welded or otherwise secured to a slidable cross-head 162. Each cross-head 162 is elongated longitudinally of the machine and is provided with an elongated slot 163. A cross bar 164 is slidable in the slot 163 to support one end of each of the cross-heads 162. The other ends of the cross-heads are supported by a driven shaft 165 rotated in a manner to be described. The shaft 165, adjacent each cross-head 162, carries a cam 166, and each cam 166 is engaged by a follower roller 167 carried by the adjacent cross-head 162.

At the ends thereof opposite the follower rollers 167, the cross-heads 162 are welded or otherwise connected to a cross bar 170. A rod 171, carried by the bar 170, is connected to one end of a tension spring 172 which biases the cross-heads 162 for movement to the right as viewed in FIGURES l, 4, 8, 9 and 10 to maintain engagement of the follower rollers 167 with the cams 166.

Each cam 166 has a substantially semi-circular surface 175 concentric with the axis of the shaft 165. The cam 166 rotates in a clockwise direction and at the following end of the surface 175, each cam is curved over and inwardly as at 176 into a dwell 177, beyond which the cam is provided with an arcuate portion 178 terminating in a second dwell 179. A short semi-circular portion 180 follows such dwell and extends into another dwell 181, followed by a curved surface 182 extending around the cam and merging into the semi-circular portion 177. Throughout approximately a half cycle of operation, the follower rollers 167 are riding over the semi-circular surface 175, thus maintaining the cross-heads 162 at their left-hand limit of movement with the tucker 158 fully retracted to the position shown in FIGURE 8.

At one point in the operation of the mechanism, as described in detail below, the set of fingers 138 which has just operated, drops below the bottom of the article to prepare for the operative movement of the tucker 158. In this momentary period, nothing mechanically engages the flap 133 to hold it in position. To insure the holding of the flap in proper position, a series of air nozzles 185, preferably four in number as shown in FIGURE 5, blow jets of air against the flap 133. This moves the flap 133 to the proper position for the efficient operation of the tucker 158. Each of the nozzles 185 is formed at the end of a pipe 186 having a cock 187 therein, and these pipes are connected to a manifold 188 mounted on supporting brackets 189 (FIGURES 2 and 4). The manifold 188 is connected through a manually operable valve 190 with a supply hose 191 (FIGURE 1) supplied with pressure from a suitable motor compressor unit 192.

A motor 200 provides power for operating the unit and drives a pulley 201 through a belt 202. A pulley 203 on the shaft 204 of the pulley 201 drives a belt 205 passing around a drive pulley 206 of a gear reduction unit 207. The output shaft 208 of the unit 207 drives a chain 209 passing around a sprocket 210 (FIGURES 2, 3 and 5) mounted on the shaft end 66. This shaft 66 also carries the sprocket 142 previously described. A chain 212 passes around the latter sprocket and around a sprocket 213 mounted on the shaft 165, thus driving the cams 166. Another drive chain 215 passes around a second sprocket 216 mounted on the shaft 165, and the chain 215 passes around a sprocket 217 mounted on the shaft 37 to drive the conveyor chains 32. This shaft drives the chains 32 to operate the pushers 38.

The shaft 165 carries a third sprocket 220 around which passes a chain 221. This chain passes around a sprocket 222 mounted on the shaft 107 which operates the cams 106 (FIGURE 11) previously described.

The shaft end 66 carries a gear 223 (FIGURES 3 and 5) meshing with an intermediate gear 224 (FIGURES 2 and 3) which, in turn, meshes with a third gear 225 mounted on the shaft 91 for driving the conveyor 86.

As previously stated, the

shafts

151 and 152 are stub shafts, the former of which lies substantially above the shaft 64 as viewed in FIGURE 3. These stub shafts are employed to provide space for the passage of the article therebetween on the drive belts 61. The chains 140 toward the observer in FIGURE 2 and toward the top of the sheet in FIGURE 3 are driven in a manner to be described.

Referring to FIGURES 1 and 5, it will be noted that the cam shaft 165 carries a sprocket 230 about which passes a chain 231, and this chain drives a sprocket 232 mounted on the shaft 150. The cam shaft 165 thus drives the shaft 150 to drive both of the chains 140.

If polyethylene is used as the wrapping material, means is employed for heating the flap end 134 to seal it with respect to the bottom layer of the sheet of wrapping material. To this end, the roller 89, over which the belt 88 operates, is apertured as at 235 to receive an electric heating element 236. The belt 88 is formed of a heat resistant plastic material so as to transmit therethrough, without damage, suflicient heat to seal each successive flap end 134. The roller 89 is of such size and the linear speed of the belt 88 is such that the heating element will reach operative position at the proper time to effect the sealing of the fiap end, such position being approached in FIGURE 10.

Operation The roll 50 on which the web 51 is wound is supported for rotation in any suitable manner. The end of the web is fed between the pinch rolls 52, and the cutting roller 53 is operated in timed relation to the machine to sever the web at the proper point to provide a wrapping sheet of necessary length. Prior to the cutting operation, the end of the web is engaged by the right-hand run of the conveyor belts 55 and moved downwardly over the plate 54 until the lower extremity of the sheet reaches a position spaced below the bottom plane of the article a distance equal to the length of the article longitudinally of the apparatus. At this point, the sheet is severed from the web.

An article placed on the plate 22 is engaged by the vertical arms 40 of the pushers and moved to the right in FIGURES l, 3 and 4. The leading end of the article moves into engagement with the severed sheet and is pushed through the plane thereof as shown in FIGURE 4, the lower portion of the sheet then becoming the bottom section 132 of the sheet. The portion of the sheet through which the article is moved loops as at 130 around the article and the top sheet layer 131 is laid against the top of the article and held down in engagement therewith by the belt 70. When the article reaches the position of the left-hand article in FIGURE 4, the projecting flap 133 including its flap end 134 will be equal to the depth of the package plus the flap end 134.

The upper cam track portions 16 (FIGURES 4-, 6 and 7) terminate short of the vertical plane of the stub shafts 35, and during movement of each pusher over the horizontal track portion 16, engagement of the lower arms 41 of the pushers with the trackway portion 16, maintains the longer arms 40 vertical. As soon as the short arms 41 of the operative pushers pass beyond the extremity of the cam trackway portions 16, the pushers are free to swing about their pivots to assume the angular position shown to the right in FIGURE 6. This swinging movement of the pushers is caused by pressure thereof against the article, and the swinging movement prevents the long arms 40 of the pushers from swinging into the wrapping sheet. The article is now supported on the belts 61 and held downwardly on the upper runs thereof by the belt 70. As one of the articles passes from the conveyor belts 61 to the belt 88, it will be supported intermediate such conveyors by the roller 100, for example, as shown by the right-hand article in FIGURE 4. The flap 133 will trail behind the article, also as shown in FIGURES 4 and 11.

As the article passes completely from the conveyor belts 61, the following end of the article will be temporarily supported by the roller 100. The operation of the chains 140 will swing the fiingers 138 downwardly adjacent the following end of the article to assure the proper folding down of the flap 133 as shown in FIGURE 8. It will be apparent that the fingers 138 will travel at the linear speed of the adjacent portions of the chains 140 until the fingers 138 pass through a plane perpendicular to the plane of said portions of the chains 140 and passing through the axis of the shaft 65. Thereafter, the fingers 138 move at an accelerated speed due to the increased diameter of the circle around which the fingers pass, concentric to the axis 65. In other words, the diameter of the circle described by the finger 138 will be greater than the diameter of the chains 140' passing around the sprockets 142.

Thus the fingers 138 are moved rapidly out of the way for the immediately following operations. The fingers 138 swing beyond the adjacent ends of the tucker plate 158, at which point the follower rollers 167, as the cams 166 rotate, move from the position shown in FIG- URE 8 to the position shown in FIGURE 9, the rollers 167 now engaging the dwells 177. At this time, it will be apparent from FIGURE 9 that the advancing end of the tucker plate 158 will project slightly beneath the following end of the article to support it. Movement of the tucker plate 158 to such position takes place at a rate of speed at least equal to the speed of the article to avoid a back drag, on the flap end 134.

As soon as the following end of the article is thus supported on the advancing edge of the tucker plate 158, the cams 120 will have rotated from the solid line position shown in FIGURE 11 to the broken line position, and the follower rollers 105 thus will drop off the position, 121 'of the cams 106, and the roller 100 will drop from the soid line position in FIGURE 11 to the broken line position, that is, to the position shown in FIGURE 9. Instantly upon the dropping of the roller 100, the cam follower rollers 167 will start to ride over the cam sur- 8 faces 178. Under such conditions, the spring 172 will urge the cross heads 162 to the right, the rollers 167 following the cam surfaces 178. The cam surfaces 178 are so designed that the tucker plate 158 moves at approximately tWice the speed of the package, and though the package is moving, the tucker plate 158 moves to the position shown in FIGURE 10, at which time, the flap end 134 will be engaged by the upper run of the belt 88 to hold it in position against the bottom of the package.

If the article is being conveyed at substantial speed, air currents engaging the flap end 134 (FIGURE 9) may tend to swing this flap end backward to prevent its proper movement over the top of the conveyor belt 88. To prevent this from occuring, jets from the nozzles 185, blowing angularly upwardly, lay the flap end 134 up against the bottom of the package. Thus, the extremity of this flap end necessarily must move over the top of the upper run of the conveyor belt 88.

Movement of the tucker plate 158 forwardly is completed when the follower rollers 167 reach the dwells 179 of the cams 166. Over the concentric cam portion 180, the tucker plate 158 will momentarily remain stationary (FIGURE 10). Thereafter, the follower rollers 167 move over the cam surfaces 182 to be retracted to their normal positions and the cross-heads will remain stationary in such position while the follower rollers 167 travel over the concentric cam portions 175 until the follower rollers 167 reach the position shown in FIGURE 8, ready for the next operation.

As the article moves over the conveyor 88, the flap end 134 will be relatively snugly engaged with the upper run of the conveyor belt 88 and will receive through such run of the belt sufficient heat from the heating element 236 to seal the flap end 134 against the bottom layer 132 of the wrapper. If a pressure-scalable wrapping material is used, the roller 71 above the conveyor roller 89 will exert sufiicient pressure through the belt 70 and through the article to seal fiap end 134.

The present method and apparatus is not concerned with the sealing of the wrapper around the sides of the article longitudinally of the conveyor 88. This may be done with machines which are conventional and associated with the conveyor 88 to fold and seal the wrapper against the longitudinal sides of the article as the latter progresses over the conveyor 88. Heretofore, it has been the general practice to place a wrapper around an article, fold the projecting edges thereof at the longitudinal sides of the article and seal them, after which the direction of movement of the articles is changed at right angles to the first sealing conveyor to seal the ends of the article. The present apparatus, therefore, makes it possible to complete the entire sealing operation on all four sides of an article without changing its direction and while the article is continuously moving. One machine has been proposed which will effect the wrapping of an article while continuously moving in one direction, but such a machine requires two sheets, one arranged over the top of the article and the other beneath the article, and fed from web rolls arranged above and below the plane of operation of the apparatus.

The present apparatus uses only a single sheet and effects the sealing of the ends while the article is moving in the same direction as the sealing of the side edges takes place. Since the advancing end of each article moves through the plane of the cut sheet, the looping of the sheet as at around the advancing end of the article makes it unnecessary to seal such end, only the following end of the article having the wrapper sealed therearound. The rate of production of the present machine, therefore, is much more rapid than present machines, and an efficient wrapping of the sheet around the article and the sealing of the sheet with respect thereto takes place.

It is to be understood that the form of the invention shown and described is to be taken as a preferred example of the same and that various changes in the shape, size, and arrangement of the parts may be made as do not depart from the spirit of the invention or the scope of the appended claims.

We claim:

1. In an apparatus for wrapping an article, means for supporting a wrapping sheet in a vertical plane, first and second horizontal conveyors for conveying an article at such a level that the article placed on said first conveyor moves through said vertical plane intermediate the length of the sheet whereby the sheet is looped around the leading end of the article as the latter moves from said first to said second conveyor, means above said second con veyor for holding against the top of the article the portion of the sheet between said loop and the extremity of the said portion of the sheet, at least one extremity of the said sheet extending beyond the following end of the article, a third conveyor aligned with said second conveyor and having an inlet end spaced from the outlet end of said second conveyor, said second conveyor moving the article to said third conveyor to be advanced horizontally thereby, and means between said second and third conveyors as the following end of the article moves therebetween for folding the extremities of the sheet into overlapping relationship and for sealing them to each other.

2. In an apparatus for wrapping an article, means for supporting a wrapping sheet in a vertical plane, first and second horizontal conveyors for conveying an article at such a level that the article placed on said first conveyor moves through said vertical plane intermediate the length of the sheet whereby the sheet is looped around the leading end of the article as the latter moves from said first to said second conveyor, means above said second conveyor for holding against the top of the article the portion of the sheet between said loop and the extremity of the said portion of the sheet, at least one extremity of the said sheet extending beyond the following end of the article, a third conveyor aligned with said second conveyor and having an inlet end spaced from the outlet end of said second conveyor, said second conveyor moving the article to said third conveyor to be advanced horizontally thereby, means between said second and third conveyors movable downwardly back of the following end of the article for folding an extremity of the sheet over such following end and into overlapping relationship with the other extremity of the sheet, and means for sealing said overlapping portions of the sheet to each other as the sheet continues to move over said third conveyor.

3. In an apparatus for wrapping an article, means for supporting a wrapping sheet in a vertical plane, first and second horizontal conveyors for conveying an article at such a level that the article placed on said first conveyor moves through said vertical plane intermediate the length of the sheet whereby the sheet is looped around the lead ing end of the article as the latter moves from said first to said second conveyor, means above said second conveyor for holding against the top of the article the portion of the sheet between said loop and the extremity of the said portion of the sheet, said portion of the sheet lying against the top of the article extending beyond the following end thereof, a third conveyor aligned with said second conveyor and having an inlet end spaced from the outlet end of said second conveyor, said second conveyor moving the article to said third conveyor to be advanced horizontally thereby, means movable downwardly between said second and third conveyors back of the following end of the article for folding downwardly said extending end of the sheet, such extending end being longer than the depth of the article to provide a flap end at its lower extremity, and means operative after said folding means has passed beneath the article for tucking said flap over the other extremity of the sheet into overlapping relationship therewith, and means for sealing such overlapping sheet ends.

4. An apparatus according to claim 3 provided with means for'moving said tucking means in the direction of movement of the article and at a speed greater than the speed of the article to effect said tucking of said flap end.

5. An apparatus according to claim 3 provided with means for moving said tucking means in the direction of movement of the article and at a speed greater than the speed of the article to effect said tucking of said flap end, said wrapping sheet being of the heat-scalable type, said sealing means comprising a heating element for heatsealing said overlapping sheet portions.

6. In an apparatus for wrapping an article, means for supporting an anticle, means for supporting a wrapping sheet in a vertical plane, first and second horizontal conveyors for conveying an article at such a level that the article placed on said first conveyor moves through said vertical plane intermediate the length of the sheet whereby the sheet is looped around the leading end of the article as the latter moves from said first to said second conveyor, means above said second conveyor for holding against the top of the article the portion of the sheet between said loop and the extremity of the said portion of the sheet, a third conveyor having a belt the top run of which is in line with said second conveyor, said third conveyor having an inlet end spaced from the outlet end of said second conveyor, a supporting horizontal roller between said second and third conveyors over which the article moves to. be supported after the following end of the article leaves said second conveyor, said portion of the sheet lying against the top of the article extending beyond the following end thereof, means movable downwardly between said second and third conveyors adjacent the following end of the article to fold downwardly said extending portion of the sheet, such extending portion being longer than the depth of the article to provide a flap end extending below the article, a tucker movable beneath the following end of the article to tuck said flap end therebeneath, cooperating means for moving said tucker slightly beneath the following end of the article, dropping said supporting roller and moving said tucker an additional distance to tuck said flap end beneath the adjacent other extremity of the sheet whereby it will be engaged by the belt of the said third conveyor, and for then retracting said tucker and moving said roller back to its normal position in engagement with the article, and

means for sealing said flap end to the adjacent other extremity of the sheet.

7. An apparatus according to claim 6 wherein said wrapping sheet is :of the heat-scalable type, said sealing means comprising a heating element for heat-sealing said flap end against the adjacent other extremity of the sheet.

8. An apparatus according to claim 6 wherein said cooperating means comprise a pair of cam devices, one for operating said tucker and the other for operating said roller, said one cam device comprising a cam having a portion for initially moving said tucker beneath the following end of the article, said cam having a dwell for moving said tucker substantially at the same speed as the article While the cam means for said roller effects downward movement thereof, said cam having a following portion for projecting said tucker beneath the article at a speed greater than the speed of movement of the article over said third conveyor.

9. An apparatus according to claim 6 wherein said cooperating means comprise a pair of cam devices, one for operating said tucker and the other for operating said roller, said one cam device comprising a cam having a portion for initially moving said tucker beneath the following end of the article, said cam having a dwell for moving said tucker substantially at the same speed as the article while the cam means for said roller effects downward movement thereof, said cam having a following portion for projecting said tucker beneath the article at a speed greater than the speed of movement of the article over said third conveyor, said cam having a still further following portion for retracting said tucker as said other 2,810,246 10/1957 Cornock et a1 53-228 12 Waite 53-230 X Schoder 53-230 Monaghan 53-233 Smith et a1 53-228 X Conti 53-228 FRANK E. BAILEY, Primary Examiner.

L. S. BOUCHARD, Assistant Examiner.

Claims

1. IN AN APPARATUS FOR WRAPPING AN ARTICLE, MEANS FOR SUPPORTING A WRAPPING SHEET IN A VERTICAL PLANE, FIRST AND SECOND HORIZONTAL CONVEYORS FOR CONVEYING AN ARTICLE AT SUCH A LEVEL THAT THE ARTICLE PLACED ON SAID FIRST CONVEYOR MOVES THROUGH SAID VERTICAL PLANE INTERMEDIATE THE LENGTH OF THE SHEET WHEREBY THE SHEET IS LOOPED AROUND THE LEADING END OF THE ARTICLE AS THE LATTER MOVES FROM SAID FIRST TO SAID SECOND CONVEYOR, MEANS ABOVE SAID SECOND CONVEYOR FOR HOLDING AGAINST THE TOP OF THE ARTICLE THE PORTION OF THE SHEET BETWEEN SAID LOOP AND THE EXTREMITY OF THE SAID PORTION OF THE SHEET, AT LEAST ONE EXTREMITY OF THE SAID SHEET EXTENDING BEYOND THE FOLLOWING END OF THE ARTICLE, A THIRD CONVEYOR ALIGNED WITH SAID SECOND CONVEYOR AND HAVING AN INLET END SPACED FROM THE OUTLET END OF SAID SECOND CONVEYOR, SAID SECOND CONVEYOR MOVING THE ARTICLE TO SAID THIRD CONVEYOR TO BE ADVANCED HORIZONTALLY THEREBY, AND MEANS BETWEEN SAID SECOND AND THIRD CONVEYORS AS THE FOLLOWING END OF THE ARTICLE MOVES THEREBETWEEN FOR FOLDING THE EXTREMITIES OF THE SHEET INTO OVERLAPPING RELATIONSHIP AND FOR SEALING THEM TO EACH OTHER.