US3319399A - Package wrapping machine - Google Patents

Description

R. F. BARBER PACKAGE WRAPPING MACHINE 7 Sheets-sheet 1 Filed April 24, 1964 z 3 -+14 z LETT www o hulrl: E i1--- o mw U May 16, 1967 R. F. BARBER 3,319,399

PACKAGE WRAPPING MACHINE May 16, 1967 R. F. BARBER PACKAGE WRAPPING MACHINE 7 Sheets-Sheet IS Filed April 24, 1964 m5 Wm,

R. F. BARBER May 16, 1967 PACKAGE WRAPPING MACHINE 7 Sheets-Sheet 4 Filed April 24, 1964 May 16, 1967 RF. BARBER PACKAGE WRAPPING MACHINE 7 Sheets-Sheet 5 Filed April 24, 1964 May 16, 1967 R. F. BARBER 3,319,399

PACKAGE WRAPPING MACHINE Filed April 24, 1964 '7 Sheets-Sheet f- R. F. BARBER PACKAGE WRAPPING MACHINE May 16, 1967 Filed April 24, 1964 7 Sheets-Sheet 7 ZIO 1Z0 71 153 f2 5 of United States Patent C) 3,319,399 PACKAGE WRAPPING MACHINE Ralph F. Barber, Elmhurst, Ill., assignor to Miller Wrapping & Sealing Machine Company, a corporation of Illinois Filed Apr. 24, 1964, Ser. No. 362,292 9 Claims. (Cl. 53--379) This invention relates to package wrapping machines and, more particularly, to such machines for wrapping packages with a limp film wrapping material.

Package wrapping machines of the semi-automatic type for wrapping packages with covering material and providing end folds for the wrapping material are well-known in the prior art. An example of such a machine is shown in Corley et al. Patent No. 2,654,196. The wrapping material is initially wrapped about the package manually by an operator and the package is placed at a first station of the machine where the ends of the wrapping material are formed and folded to lie against the end of the package. 'I'he package is then automatically .advanced to a second station where hea-t is applied to the folded ends and to the overlapped Wrapping material at the bottom of the package. The heat functions to seal the overlapped sections of wrapping material together to form a completed package. This has been done with materials such as cellophane coated with heat-sensitive material and no problem has been encountered due to the substantial body of the cellophane. Such machines have not been satisfactory in Working with limp films, such as polyethylene films and trademarked films, such as Pliofilm and Saran.

An object of this invention is to provide a wrapping machine for providing a tight, neat wrap of a package utilizing a limp film.

Another object of the invention is to provide a wrapping machine for limp films in which partial heat sealing is accomplished at the first folding station of the machine to tack parts of the wrapping material to each other and thus hold the limp film in Vfolded relation during advance of the Wrapped package to the second station at which the heat is applied to securely seal the wrapping material together.

Another object of the invention is to provide a wrapping machine as defined Ain the preceding paragraph in which the amount of heat applied to the wrapping material at the second station is accurately controlled to provide heat at a sufficiently low rate to prevent burning of the wrapping material while providing the heat for a sufficient length of time to have the heat transmitted through the wrapping material and effect a good seal.

Still another object of the invention is to provide a wrapping machine as defined in the preceding paragraphs in which the mechanism is constructed with a minimum number of parts in a manner to provide long, trouble-free service.

A further object of the invention is to provide a wrapping machine in which the wrapping material at the ends of the package is folded by folding mechanism with parts of lthis folding mechanism being heated and movable during the initial folding of the ends of the package to tack together overlapped layers of the wrapping material to temporarily seal the ends of the package and hold the wrapping material in folded relation until the package is finally sealed.

An additional object of the invention -is to provide a wrapping machine in which heat is applied to the bottom and ends of the package to seal the wrapping material by movable heated members which are moved into engagement with the package during a cycle of operation of the machine and time delay means are provided for stopping 3,319,399 Patented May 16, 1967 rice the cycle of fthe machine for -a predetermined time period to provide the proper amount of heat to the wrapping material for sealing thereof with the completion of the time delay period resulting in re-starting the cycle of the machine to complete the movement of the machine parts, with this time delay being predetermined by an operator.

Further objects and advantages will become apparent from the following detailed description taken in connection with fthe accompanying drawings in which:

FIG. 1 -is a fragmentary side elevational view of the Wrapping machine with parts broken away and with the drive mechanism shown in an elevated position;

FIG. 2 is a perspective view looking toward the left front corner -of the machine, as viewed in FIG. 1;

FIG. 3 is a detailed view on an enlarged scale and in elevation of the finger folding mechanism for one end of the package;

FIG. 4 is `a section taken generally along the line 4-4 in FIG. 3;

FIG. 5 is a view similar to FIG. 3 showing the folding fingers in their positions to fold and tack the Wrapping material at one end of the package;

FIG. 6 is a section on a further enlarged scale taken generally along the line 6-6 in FIG. 3;

FIG. 7 is a view similar to FIG. 6 and taken generally along the line 7-7 in FIG. 5;

FIG. 8 is a generally vertical section taken generally along the line 8 8 in FIG. 3 on `a further enlarged scale and showing the lingers in their retracted position;

FIG. 9 is a view similar to FIG. 8 and taken generally along the line 9-9 in FIG. 5;

FIG. 10 is a plan view of the structure shown in FIGS. 8 and 9 and shown in full line in the position of FIG. 9 and in broken line in the position of FIG. 8;

FIG. l1 is a view taken .along the line 11-11 in FIG. 8;

FIG. 12 is an elevational view of the second station of the machine in which the bottom and ends of the package `are sealed and with portions of the bottom sealing mechanism shown in section;

FIG. 13 is a plan view of the structure shown in FIG. 12;

FIG. 14 is a section taken generally along the line 14-14 in FIG. l2; and

FIG. 15 is an electro-mechanical schematic of the control system for the machine.

While this invention is susceptible of embodiment in many different forms, there is shown in the drawings 4and will herein be described in detail an embodiment of the invention with the understanding that the present disclosure is to be considered as an exemplilication of the principles of the invention and is not intended to limit the invention to 'the embodiment illustrated. The scope of the invention will be pointed out in the appended claims. Y The semi-automatic Wrapping machine disclosed herein is of basically the same construction as disclosed in the Corley et al. Patent, No. 2,654,196-, granted Oct. 6, 1953, and the disclosure contained therein is incorporated herein by reference with respect to the general structure.

The wrapping machine comprises a main frame having supporting legs including legs 10 and 11 with a platform near the lower end of the legs indicated generally at 12 which supports the primary power system for the machine. This system includes a motor 26 (FIG. 15) which drives a belt 13 engaging a pulley 14 (FIGS. 1 and 15) on a rotatable shaft 15 supported in bearings, one of which -is shown at 16, with this shaft driving an electrically operated clutch 17. With the clutch engaged, the output of the clutch extends into a gear box 18 with the output from the gear box driving a sprocket 19. The sprocket 19 drives a chain 20 engaging a sprocket 21 on a rotatable cam shaft 22. Another sprocket 23 drives a.

chain 24 for driving a shaft (not shown) corresponding to the shaft 85 of the Corley et al. patent and which has directly mounted thereon a crank 100 similar to that of the Corley et al. patent which cycles a rocker arm 25 corresponding to the rocker arm 98 of the Corley et al. patent. The wrapping machine has two stations indicated generally at and 31 in FIGS. l and 2.

The folding functions accomplished at the first station are, in part, accomplished by the initial manual insertion of a package into the station. The bottom length of wrapping material extending beyond the ends of the package is folded upwardly upon insertion of the package, movable fingers fold in the leading and trailing edges of the wrapping material at the end and then the top portion of the wrapping material is folded down over the remainder of the wrapping material at the ends of the package. The structure at station 30` embodies a pair of supporting rails 32 and 33 at opposite sides of the station onto which a package is placed and, as the placement occurs, stationary folding fingers adjacent each rail cause the lower part of the wrapping material to move upwardly. These fingers are similar at each side of the station, with the fingers adjacent the rail 33 including a pair of spaced apart stationary folding fingers 34 and 35 and a center finger 36. A pair of movable folding lfingers 37 and 38 are caused to move after the package is in position to fold the leading and trailing edges of the wrapping material over the bottom material that has been folded up and, as a final step in the operation, the wings 39 and 40 which are in spaced-apart relation come down along side the ends of the package `and sweep across the ends while at the same time, all of the folding fingers are lowered away from the package.

VReferring particularly to FIGS. 1, 2, 3, and 5, the stationary fingers 34, and 36 are adjustably mounted on a plate 45 which is secured to a tube 46 which is movable along a fixed rod 47 secured to the frame of the machine, with the opposite ends of the plate having suitable guide means engaging the frame (not shown).

The movable fingers 37 and 38 are also mounted on said plate by pivot means providing compound pivoting movement of these fingers. The fingers have one pivotal movement for folding the wrapping material, as in the Corley et al. patent. The second pivotal movement is new and provides for movement of the fingers toward the package end to apply heat to the wrapping material and make tacks in the material.

The mounting ofeach of the movable fingers 37 and 38 is similar, with the mounting for finger 38 being shown particularly in FIGS. 8, 9, 1l and also in FIGS. 3 and 5. The mounting includes a bracket 50 extending downwardly from the plate 45 and mounting a block 51 which is pivotally mounted to the bracket by a pin 52 extending lengthwise of the plate 45 for providing pivot movement of the finger 38 about an axis extending parallel to the plate 45 which results in movement of the finger 38 toward and away from the package, as more fully described hereinafter. The block 51 carries a pivot pin 53- on which the finger 38 is mounted for pivoting about an axis transverse to that of the pin 52, whereby the finger 38 can move from the withdrawn position, shown in FIG. 3, to the fully operative position, shown in FIG. 5.

With the compound pivoting, as provided by the pivot pins 52 and 53, the fingers 37 and 38 can move about the pivots of the pins 53 between the position shown in FIG. 3 and FIG. 5, with the final movement of the fingers being from the position of FIG. 8 to that of FIG. 9 by movement about the pivot pins 52.

The actuating movement of the fingers 37 and 38 is obtained through a single operating member in the form of a cam track 55 having spaced-apart rails which moves from the lower position with the fingers retracted as shown in FIGS. 3 and 8 to an elevated position with the fingers in tacking position, as shown in FIGS. 5 and 9. The cam track 55 is supported for movement between these positions in Aa somewhat arcuate path by a pair of levers, with a lever 56 pivoted to the frame 45 at a pivot 57 and pivoted to a bracket 58 on the cam 5S by means of a pivot connection 59. A lever 60` is pivoted to the frame plate 45 at 61 and pivoted to the cam track 55 at 62 to support the other end of the cam track. Movement is imparted to the lever 60 by an inner rod of an elongate actuator of the Bowden wire type, with this inner rod 63 being connected to the lever 60, at 64, as shown in FIGS. 3, 5 and 1l.

Each of the fingers 3-7 and 38` have rollers 65 and 66, respectively, engageable within the cam track 55 and, as shown, the roller 66 is rotatably connected to the lower end of a finger arm 67 which extends upwardly and has a hot plate 68 secured thereto.

The relation of the cam roller 66 to the finger pivot 53 causes a pivoting of the finger from the position of FIG. 3 to that of FIG. 5, as the cam track 55 is raised. Further, the offset relation of the c-am roller 66 relative to the finger pivot 52 results in a force tending to urge the finger 38 toward the package end when the finger is permitted to do so. The control of this action is determined by a cam 70 secured to the stationary folding finger 35 and being fastened to a spaced plate 71 by means of threaded connectors 72 passing through spacer blocks 73 to define an enclosure for the finger arm 67. The cam 70 has a surface 74 which holds the finger in a position removed from the package end and a second surface 75 closer to an end of the package which is positioned to permit the finger 67 to move inward when the finger h-as been moved into a position to move against the end of the package and make the heat sealing tack. An insulating block 76 is secured to the finger arm 67 through which electrical leads extend and it is this block which actually engages the cam surfaces 74 and 75.

The hot plate 68 carried by the finger 38 consists of a metal block having heating elements therein supplied with electricity for creating heat and with the block having a thin projection 80 to pass beyond the plane of the stationary folding finger 35 and press against the end of the package to apply heat to overlapped sections of wrapping material and form a tack by sealed together sections of wrapping material. To prevent adherence of the element 68 to the Wrapping material, the hot plate is surrounded by a sleeve 8l 4of Tefion which does not adhere to the Wrapping material, with the sleeve being held in place by a metal clip 82.

The relation of the parts and the movements of the fingers is clearly shown by comparing the positions of the fingers shown in FIGS. 6 and 7 with the broken line `and full line positions, respectively, shown in FIG. l0. As shown in the broken line position of FIG. l0, the finger 38 is in a retracted position to the outside of the plane of the folding finger 35, which is the position of the finger shown in FIG. 6. As the cam track S5 is elevated by operation of the motion-transmitting link 63, the cam rollers 66 cause the fingers to move along the surfaces 74 of the cam blocks 70 and about the pivots 53 until such time as the fingers are adjacent the cam surfaces 75' of the cams 70, at which time the fingers can move toward the package to the full line position of FIG. 10` and as shown in FIG. 7.

The structure for finger 37 is the salme as for finger 38 and the same parts have been given the same reference numeral.

After the tacks are made by the movable folding fingers 37 and 38, the fingers move outwardly to the outside of the plane of the stationary fingers 34 and 35 and then the pair of wings 39 and 46 move downwardly, as described in the Corley et al. patent toy complete the package wrap. These wings are supported by a pair of plates, with one being indicated at 90. The support plates are each connected to a pair of wing arms 91 and 92` pivoted on the frame for movement about pivots 93 and 94, respectively. The wings are pulled down by a pair of pulldown arms 95 and 96, at opposite sides of the station 30, as shown in FIG. 2, with these pull-down arms being connected to a cross-shaft 97, shown in FIG. 1 extending between a pair of pull-down frame arms, one of which is shown at 98 and which are operated by interconnecting linkage from a wing actuating cam 99 corresponding to the actuating cam 105 in the Corley et al. patent.

A package is ejected from station 30 and moved to station 31 by .pushers 99a and 99h which correspond to the pushers 172 of the Corley et al. patent and which are actuated in the same manner. It is this physical transfer of the package which tends to disturb the wrapped material. The slight heat sealing or tacking of the wrapping material enables the transfer to take place.

The timing of the fingers 37 and 38 and the wings 39 and 40 with respect to the over-all cycle of the machine will be described subsequently.

At the completion of the initial tack sealing operation at the station 30 the pushers 99a and 99h push the package into station 31. At station 31, the overlapped portions of wrap-ping material at the bottom of the package are heat sealed and also the overlapped portions of wrapping material at the end of the package are heat sealed. This is accomplished by a bottom sealer, indicated generally at 100 in FIGS. 2, 12 and 14 and by a pair of side sealers indicated generally at 101 and 102 in the same figures.

The botto-m sealer 100 defines a platform on which the package rests, with there being four spaced rods 103, 104, 105 and 106 about which a continuous sleeve or belt of Teflon 107 extends. A hot plate 108 extends across the station 100 and is mounted for slight up and down movement relative to the bars 104 and 105 by a pair of pins at opposite ends with one pin being shown at 109 .in FIG. 12 to permit the up and down movement within the range of the slots 110 in the bars 104 and 105. Normally, the

hot plate 108 lies beneath the plane of the Teti-on sleeve 107. However, during a cycle a pusher member urges the hot plate 108 upwardly against the packa-ge which acts through the Teflon 107. This pusher comprises an arm 110a, as shown in FIGS. 12 and 14, having a layer of resilient material 110b thereon which acts through the lower part of the Teflon sleeve 107 to urge the hot plate 108 upwardly. After sealing of the package, the Teon sleeve 107 can shift along with the package and, as the package moves off the Teflon, the Tefion readily peels away from the wrapping material.

Each of the side sealers 101 and 102 are similar and side sealer 102 will be described in detail by particular reference to FIGS. 12, 13 and 14. This side sealer embodies ahot plate 110 spanning the bottom sealer 100.

This hot plate is floatingly mounted from an overhead support bracket 111 by a pair of pivoted links 112 and k113 .which arepivotally connected `at each end of the plate 110 to permit movement of the plate 110 toward and away from an end of the package and independent.

movement of the opposite ends thereof. The plate 110 is surrounded by a sleeve or belt of Teflon 114 which Vpasses about a pair of vertically disposed rollers 115 and 116. Each of these rollers is suspended from above and mounted by bearings on their respective axles 117 and 118. The axle 117 is supported from an arm 119 which is pivoted by a pin 120 to a block 121 secured to the vframe member 111. A pair of springs 122 and 123 are positioned between the arm 119 and the block 121 to cause the` roller 115 to float in an intermediate position. The axle 118 is similarly mounted to an arm 124 and similar springs 125 and 126 are provided. The rollers 115 and 116 thus provide a floating mount for the sleeve 114 of Teiion and permit the movement of the Teflon sleeve outwardly with the hot plate 110 as it is moved against the end of a package.

The hot plate 110 is caused to move toward a package from its normal position by an actuating plate 130 having a pair of presser clips 131 and 132 urged outwardly a `limited distance away from the actuating plate by springs 133 to provide a yielda-ble pressing force of the hot plate against the package. The actuating plate 130 is guided in its movement by a pair of guide pins with a pin 134 vbeing fixed to the back side of the actuating plate and passing through a guide sleeve 135 extended between a pair of wing mounting plates 136 and 137. Additional guiding is obtained by a pin 138 fixed to the wing mounting plate 137 and extending th-rough a bearing sleeve 139 mounted on the actuating plate 130. The plate 130 is caused to move from a cam control which operates the movable inner wire 140 of a motion-transmitting connection which connects to a bell crank 141 pivoted to the mounting plate 137 by a pivot 142 and having an actuating end 143 engaging a pin 144 extending through the mounting plate 137 and connected to the actuating plate 130. Thus, a pull on the wire 140 causes the actuating plate 130 to move toward the package and the ciips 131 and 132 then engage the back side of the hot plate 110 through the back portion of t-he Teflon sleeve 114 to press the Teflon exposed face against the package and with the heated plate 110 directly therebehind. Similar parts associated with t-he side sealer 101 have been given the same reference numerals as the parts for side sealer 102, since the parts are identical.

Upon completion of sealing of the package, an overhead, four-way motion feeder indicated generally at in FIG. 2 functions to come down Ibehind a package and move the package out of the station 31. As the package is moved out of the station 31, the sleeves 114 of Teflon can move along with the package and thus the package peels away therefrom as the package leaves the sealing station.

Referring to FIG. 15, the movable finger heaters 37 and 38, the bottom sealing hot plate 108 and the side sealing hot plates 110 are all supplied from a line through a main power switch 151 with conventional wiring -being shown supplying power to the heating coils of these plates and with there being thermostats 152 and 153 associated with the side sealing heating hot plates 110 and the bottom hot plate 108, respectively, to control the temperature of these plates.

The electrical control circuit includes a rectifier 160, a manually settable time delay device 161 of a cornmercially available type and three operating switches with the switch 162 being normally open, a switch 163 being normally closed, and the switch 164 being normally open. The switches 162 and 164 are in parallel, whereby initiation of operation by manual depression of a handle 165 closes switch 162 to complete a circuit between rectier A.C. terminals 166 and 167 which connect between the main lines 168 and 169. This circuit is maintained after release of the handle 165 by the normally open switch 164 -being closed by a cam 170 on the cam shaft 22 which closes the switch. The closing of this circuit to the A.C. side of the rectifier results in supplying D.C. to the electric clutch 17 through lines 171 and 172 which drives the cam shaft 22 and the drive chains referred to previously. This circuit has been completed through the normally closed contact and common of the switch 163. During the cycle when the package has arrived at the sealing station 31, and

the side sealers and bottom sealers have been moved to a position to apply heat to the package, the cam 175 on the cam shaft 122 trips the switch 163 to an open position to break the circuit and de-energize the clutch 17 and cause the time delay device to operate. This unit is of a commercially available type and, as known, can be manually set for the preferred amount of time delay. When the proper amount of time yhas elapsed, a cam 176 engages a switch 177 in the unit to close the circuit between main line 169 and a line 180 leading to the switch 164 which is still in closed condition under cam which connects the A.C. rectifier connection 167 back into the circuit with the cycle continuin-g until the switch 164 is returned to its normally open position. On the main cam shaft 22 there are four operating cams, with two of these cams being identical and for operating the side folding fingers and the motion-transmitting rods 63 thereof. One of these cams is shown at 190 and operates a cam roller 191 mounted on an arm 192 pivoted to the frame and with the end of the arm :being connected to the motion-transmitting rods 63. The cam roller 191 is caused to follow the cam by a tension spring 193. The second pair of cams includes the cam 195 operating against a roller 196 and mounted on an arm 197 urged against the cam by a spring 198.

When a cycle starts by the closing of the clutch 17, the slope 199 on the cam 190 immediately causes the folding fingers 37 and 38 to move to the position shown in FIGS. and 9 to form the heat tacks on the ends of the wrapping material. This condition is maintained until the follower roller 191 moves onto the slope 200 of cam 190, at which time the fingers 37 and 38 move outwardly from the tack position, Ibut still are extended and not returned to their inoperative position. At this time, the wing pull-down frame 98, shown in FIG. 1, is operated to pull down the wings 39 and 40 to fold down the ends of the package and this frame, through a connecting chain 262 (FIG. l) pulls down the finger pull-down frame 293, pivoted at 2114, on the main frame which is connected to the tubes 46 on which the fin-gers are mounted `by means of the mounting plate 45 so as to pull the fiiugers downwardly at the same time as the wings move down past the ends of the package supported on the guide rails 32 and 33. The wing operation and lowering of the folding fingers is as described in the aforementioned Corley et al. patent. With the wings 39 and 4l)` still down alongside the package, the pushers 99a and 99h are operated to move the package into the sealing station 31 and, at this time, the overhead conveying unit comes forward to a position to convey the package. When the package is at station 31, Ia high 210 on the cam 195 causes the actuating plates 130 for the side sealing hot plates 110 to move in and press against the sides of the package, while, at the same time, an extension of the arm 197 is connected to a vertically extending rod 211 (FIG. 1) which connects to the operating arm 110b which causes the bottom :hot plate 198 to move upwardly against the vbottom of the package. At this time, the switch 163 is operated by a pin on the cam 175 to shift the condition of the switch 163 from normally closed to normally open and disengage the drive clutch and start the time delay device 161. AS soon as the timer operates its switch 177 to re-engage the clutch 17, the cycle continues, with the follower roller 196 going back onto its low to permit retraction of the side and 4bottom sealing pilates, with the wings 39 and 40 again rising along with the side folding fingers and at the last part of the cycle the follower rolle-r 191 goes into its low to permit return of the folding fingers 37 and 38 to their inoperative positions, as shown in FIGS. 1 and 3.

From the foregoing description, it will be seen that a mechanism has `been provided for making tight wrappings with heat scalable limp film and in which heat can be applied by members which readily peel from the heated wrapping material.

I claim:

1. A package wrapping machine for utilizing heat sealable limp film having first and second operating stations, the first of said stations including means for folding the wrapping material at the ends of a package including movable folding fingers, means at said second station for heat sealing the wrapping material at the bottom and the ends of the package, said movable folding fingers including heated surfaces for making tacks in the wrapping material at the ends of the package to stiffen the wrapping material .for advance to saidsecond station, said ,movable 8 folding fingers being mounted for pivoting toward each other to fold the ends of the wrapping material, and means providing an additional pivot axis for each finger whereby the fingers pivot toward the package end to apply the heat against the package ends.

2. A package wrapping machine for utilizing heat sealable limp film having lfirst and second operating stations, the ,first of said stations including means for folding the wrapping material at the ends -of a package including movable folding fingers, means at said second station for heat sealing the wrapping material at the bottom and the ends of the package, said movable folding fingers including heated surfaces for making tacks in the wrapping material at the ends of the package to stiffen the wrapping material for advance to said second station, said means at the second station including a pair of spaced-apart hot plates engageable with the ends of the package and a third hot plate engageable with the bottom of the package, a plurality of Teflon belts associated one with each of said hot plates, and means mounting each of said belts for movement with a package as a package leaves the second station whereby the package and belts easily peel apart.

3. A wrapping machine as defined in claim 2 in which said hot plates are movable toward and away from a package and cam controlled means for moving said hot plates.

4. A wrapping machine as defined in claim 3 in which an electrical circuit including an electrically operated clutch controls the operation of the cam controlled means, and a time delay system for temporarily deenergizing said clutch and stopping said cam controlled means with the hot plates against the package for a predetermined period of time.

5. A wrapping machine for folding the ends of limp film wrapping material about the ends of a package comprising, a support for a package, stationary folding fingers adjacent said support for partially folding the wrapping material at the ends of the package as the package is placed on the support, a pair of movable folding fingers for each end of the package movable toward each other to further fold the wrapping material, means mounting each movable finger for compound pivoting movement about two axes normal to each other with movement about one axis accomplishing said further folding and movement about the other axis causing the fingers to move toward the end of a package, a hot plate on each finger operable to make a tack in the wrapping material in moving about said other axis, and operating mechanism for moving said fingers about both of said axes including means urging said fingers about the other axis while moving the fingers about the one axis, and cam means holding the fingers against movement about the other axis until the movement of the finger about the one axis is completed.

6. A wrapping machine as defined in claim 5 in which each of said movable fingers has a sleeve of Tefion providing a package-contacting surface which will not stick to the package upon the application of heat to the package by the movable linger.

7. A wrapping machine as defined in claim 5 in which said stationary folding fingers and movable folding fingers are mounted for bodily movement downwardly away from a package on the support, folding wings movable down past the support to fold down the wrapping material, means connecting the fingers to the wings to move the fingers away from the package as the wings move across the ends of the package, and means for moving the movable fingers away from the package ends about said other axis prior to downward bodily movement of the fingers.

8. A wrapping machine having a first station for folding wrapping material at 4the ends of a package, and a second station for sealing the wrapping material at the bottom and ends of the package, said second station including a pair of lspae, l-apar t hot plates for the package ends, means for moving said hot plates toward the ends of a package, a bottom hot plate mounted for vertical movement toward the bottom of a package, and means for controlling the time of package engagement by said hot plates and the temperature thereof including an operating cam shaft, an electric clutch for driving said shaft, an electric circuit for controlling said clutch including an operable switch for deenergizing said clutch when the hot plates engage a package, and a settable time delay device for re-energizing said clutch upon the passage of a predetermined period of time.

9. A Wrapping machine having a first station for folding wrapping material at the ends of a package, and a second station for sealing the wrapping material at the bottom and ends of the package, said second station including a pair of spaced-apart hot plates for the package ends, means for moving said hot plates toward the ends of a package, a bottom hot plate mounted for vertical movement toward the bottom of a package, means for controlling the time of package engagement by said hot plates and the temperature thereof, a plurality of Teflon belts associated one with each of said hot plates, means mounting each belt surrounding the associated hot plate and in floating relation thereto whereby the belt can remain adhered lto a package as the hot plate moves away from the package, and means mounting each of said belts for travelling movement with a package as a package leaves said second station whereby the package and belts can easily peel away from each other.

References Cited by the Examiner UNITED STATES PATENTS 1,818,498 8/1931 Milmoe 53-379 X 1,883,229 10/1932 Bent 53--379 1,968,190 7/1934 Clark 53-33 2,654,196 10/1953 Corley et al. 53-77 2,745,234 5/1956 SchOOler 53-379 20 TRAVIIS, S. MCGE-HEE, Primary Examiner.

Claims (1)

1. A PACKAGE WRAPPING MACHINE FOR UTILIZING HEAT SEALABLE LIMP FILM HAVING FIRST AND SECOND OPERATING STATIONS, THE FIRST OF SAID STATIONS INCLUDING MEANS FOR FOLDING THE WRAPPING MATERIAL AT THE ENDS OF A PACKAGE INCLUDING MOVABLE FOLDING FINGERS, MEANS AT SAID SECOND STATION FOR HEAT SEALING THE WRAPPING MATERIAL AT THE BOTTOM AND THE ENDS OF THE PACKAGE, SAID MOVABLE FOLDING FINGERS INCLUDING HEATED SURFACES FOR MAKING TACKS IN THE WRAPPING MATERIAL AT THE ENDS OF THE PACKAGE TO STIFFEN THE WRAPPING MATERIAL FOR ADVANCE TO SAID SECOND STATION, SAID MOVABLE FOLDING FINGERS BEING MOUNTED FOR PIVOTING TOWARD EACH OTHER TO FOLD THE ENDS OF THE WRAPPING MATERIAL, AND MEANS PROVIDING AN ADDITIONAL PIVOT AXIS FOR EACH FINGER WHEREBY THE FINGERS PIVOT TOWARD THE PACKAGE END TO APPLY THE HEAT AGAINST THE PACKAGE ENDS.

Images