US2149944A - Strip sealer for wrapping machines - Google Patents

Description

March 7, 1939. A. VAN VEEN 2,149,944

STRIP SEALER FOR WRAPPING MACHINES Filed Nov. 29, 1935 3 Sheets-Sheet l INVENTOR March 7, 1939. A. "VAN VEEN 2,149,944

STRIP SEALER FOR WRAPPING MACHINES Filed Nov. 29, 1955 s Sheets-Sheet 2 WQX E 1 x ATTORNEY March 7, 1939. A. VAN'VEEN 2,149,944

STRIP SEALER FOR WRAPPING MACHINES Filed Nov. 29, 19:55 '3 heets-Sheet s m 9 FIG. .6

INVENTOR ATTORNEY Patented Mar. 7, 1939 UNITED STATES PATENT OFFICE STRIP SEALER FOR WRAPPING MACHINES Application November 29, 1935, Serial No. 52,023

27 Claims.

This invention relates to improvements in sealing mechanisms, more particularly'to wrapping machines such as are commonly used for wrapping bread, cartons and the like, wherein the margins of the wrapper are lapped on the bottom of the package to form a bottom seam and the ends of the wrapper are folded over the package ends. In such machines, bakery products are now generally wrapped in waxed paper because of the ease with which the same may be heatsealed. Heretofore, in such machines, it has been found difficult to properly seal a package having a non-waxed paper wrapper. The main object of the invention, therefore, is to apply a glued or gummed label or sealing strip to the end folds and/or bottom seam of the nonaxed paper wrapper to effectively seal the same.

It is well known that waxed paper-has a number of drawbacks as a wrapping for bakery products, but it is nevertheless in wide use because of the ease with which it may be sealed and its moistureproozf nature which prevents drying out of the product. However, when the hot, moist bread or other bakery product is wrapped in waxed paper, the excess moisture retained in the package may cause the bread to become relatively soggy and lose its original crispness. .This condition has also been found to promote moulding of the bread. Another objection to waxed paper is that 'the same may impart a waxy flavor to the bread, which is objectionable to some people. Another serious objection to waxed paper is that it materially increases its cost and weight. Still another objection to waxed paper is that it does not permit-clearcut printing thereon or the production of clear undulled colors, since the wax has a clouding efiect on such printing or colors. Despite these drawbacks, waxed paper is widely used because ordinary paper offers mechanical difficulties in sealing the paper after it has been wrapped about the bakery product. In accordance with the above mentioned object of the invention, the enumerated disadvantages I of waxed paper may be avoided by using ordinary paper for the wrapper and sealing the latter with a sealing strip.

With these ends in view, there is provided a web-feeding mechanism comprising two sets of grippers successively acting to draw a web of sealing material under the bottom seam of the package, the first set of grippers carrying a knife which is actuated at the proper time to sever the desired length of sealer strip from the web. The construction of the present web-feed permits adjustment thereof to vary the length of sealing material drawn, and by reason of the mounting of the knife on one set of grippers the mere adjustment of the web-feed will vary the length of sealer strip cut from the web. A further object of the invention, therefore, is to vary the length of the sealer strip whereby packages of various lengths may be sealed, or the overlapping of the strip ends on the end folds may be varied, or a length of strip sufiicient to cover the bottom seam only may be obtained.

Still another object of the invention is to bring the printed matter on a printed sealing material, in case the same is used, into predetermined relation with the package; and to this end the sealing material is provided with equally spaced perforations through which contact is successively made to energize electrically controlled mech-v anism which stops the feeding of the web of sealing material with the printed label or design 1 the desired relation to the package.

Still another object of the invention is to so support the package that the sealer strip may be applied to its bottom seam. To this end the package is supported at sealing position by stationary members having a gap therebetween, the gap being bridged by guide rails at the time the package is delivered to sealing position above the gap. In this manner the guide rails keep the packages from dropping into the gap during their delivery to sealing position but then are retracted from underneath the package to permit the sealing strip to be placed on the bottom seam. A further object of the invention is the provision of novel mechanism for pressing the sealing strip against the bottom seam and end folds of the package immediately after the guide rails are retracted. Said mechanism is controlled by a feeler arranged in the path of the packages advancing into sealing position so that said mechanism operates only when and if an article is delivered to sealing position. A pair of rotary folded fingers then lay the ends of the sealing strip over the end folds of the package, and these folders are formed of resilient material wherefore they can flex to accommodate individual variations in the lengths of the packages, and are furthermore relatively adjustable to operate on packages of various lengths.

Other objects of the invention therefore, are to provide package-controlled mechanism for applying the sealer strip to the package, and adjustable strip folders for laying the sealer strip ends over the package end folds. The latter are held against the ends of the package by guide strips while the latter advances from the end folders over the guide strips by the strip folders. Accordingly, an auxiliary object of the invention is I to keep the package end folds closed during the movement of the package into sealing'position.

With these and other objects not specifically mentioned, the invention consists in certain constructions and combinations hereinafter fully described and then specifically set forth in the. claims hereunto appended.

Generally stated, in the embodiment of the invention herein illustrated, the package is supported in an upright position and a sealer strip is applied to the bottom seam and, if desired, to the end folds also of the package. In the best constructions contemplated there is provided means for supporting in upright position a package having a bottom seam and end foldsin its wrapper, and mechanism applying a strip of sealing material over the bottom seam and end folds only of the package to seal the same. Preferably, the package is supported in'upright position by means including two sets of spaced opposed stationary members, and the strip-applying mechanism includes a web feed for drawing a web of sealing material along said gap, a knife for severing a sealer strip therefrom, and devices for pressing the sealer strip through said gap against the bottom seam and-then wiping the strip ends over the end folds of the package. Furthermore, in the best constructions, the web feed includes two sets of successively acting moving grippers and the knife is mounted on one set of grippers.

The particular machine selected to illustrate the invention is but one of many possible concrete embodiments of the same, and the construction thereof maybe widely varied within the scope of the invention. Therefore, the invention is not to be restricted to the details illustrated parts Fig, 1 is a plan view of the strip sealing mech- Fig. 2 is a sectional end elevation of the same, taken on line 2-2 of Fig. 1;

Fig. 3 is a side elevation of one set'of grippers of the web-feeding mechanism;

Fig.4 is a side elevation of the other set of grippers, showing the knife mounted thereon;

Fig. 5 is a detail perspective view of the electrical control for the web feed, showing contact disk and roller making contact through one of the perforations of the sealing material;

Fig. 6 is a side elevation of the strip sealer taken on line 9-6 of Fig. 1;-

Fig. '7 is an end elevation of one set of grippers taken on line 1-1 of Fig. 3;

Fig. 8 is an end elevation of the other set of grippers taken on line 8-9 of Fig. 4;

Fig. 9 is a sectional end elevation of the package detector mechanism, taken on line 9-9 of Fig. 6 v

has been previously enfolded in its wrapper durattached to one side of the frame II.

S is led over a contact roller 21 (Figs. 1, 2 and Ii),

shown) forming a part of the machine, to a so- 1 called sealing position which is located intermediate the ends of extensions 29 and the delivery guides 2| of the sealing mechanism. In order to bridge the gap between said extensions and guides while a package is being delivered to the sealing station. and thus support the package during this movement, a bottom guide is periodically advanced to bridge said gap and then retracted to permit the sealing material to be drawn under the package. While in the sealing position, the ends of the package P are engaged in order to prevent opening of the end folds, by a pair of narrow, resilient, guide strips 22 extending from the end folders l8 of the wrapping machine. The bottom guide consists of a number of guide rails 23 attached to blocks pivotally 'connected to the ends of a forked arm 24 loosely mounted on a cross-shaft 25 supported in bearings of frame l5.

. The sealing material, which is to be placed over the bottom seam and the end folds of the package P, may be fed in the form of a web 8 from a reel R loosely mounted in a bracket 23 The web a guide roller 29, a paste-applying roller 29. and two other guide rollers and 3| into the webfeeding mechanism of the strip sealer. The contact roller 21 is supported in a pair of arms 32 attached to bracket 28; Roller 29 is also pivoted to said bracket 29. The paste-applying roll er or wheel 29 is mounted on a shaft 33 supported in bearings provided in the sides of a paste reser- 30. The paste reservoir 34 is supported by brackv et 29, and the guide roller 31 is' pivoted to a pai I of lugs 35 of frame I! (Figs. 1 and 2).

The web S is pulled into the machine and underneath the package P by means of two sets of grippers comprising movable Jaws 39 and 31 having interfitting configurations and being mounted on horizontally reciprocating blocks 39 and 39 the latter having flanges 93 and 94 which constitute the stationary jaws of their respective set of grippers. Each of the blocks is equipped with a bushing 40 having a spiral channel retaining a number of balls 4| (Figs. 3, 4, 7 and 9) The balls of block 39 engage inv a'right hand spiral groove 42 of shaft 43, while"'the balls held by block 39 engage in a left hand "spiral groove- 44 of the same shaft. Groove 42 runs from the center of the shaft 43 towards one end of the same, while groove 44 runs from the center of shaft 43 towards the other end of said shaft. Therefore,upon rotation of the latter, the blocks 38 and 39 and their Jaws 39 and 31 respectively, move either towards or away from each other, depending upon the direction of rotation of shaft 49. The leading end of the web of sealing material S is first gripped against the flange 33 by the jaw 39 when the latter is closed by mechanism hereinafter described, whereupon rotation of shaft 43 in the properdirection moves this set of grippers towards the center of the machine, thereby pulling the web S of! the supply reel R. At the center of the package, which is also the center of the sealing station, the jaw 36 while gripping the leading end of web S, is met by the open jaw 31. The latter is equipped with tongues 45 which enter corresponding notches of jaw 36, and the latter has a tongue which enters the notch 46 of jaw 31. Thereupon the jaw 31 closes against its flange 84 and grips that part of the web S lmderlying the notches of jaws 36. The latter then releases the strip and remains in an open position while the shaft 43 rotates in the opposite direction, whereupon the jaws 36 and 31 move away from the center of the package toward their respective ends, thus causing the jaw 31 to pull the web S further across the machine and underneath the package P while jaw 36, retreating in an open position, moves over the web back to its starting position.

Shaft 43 is supported in bearings of frame l5 and carries a pinion 41 periodically driven in opmounted on a cross-shaft 52 also supported in bearings of frame I5. 0n shaft 52 is fixed a flange 53 (Figs. 2 and 6) to ,which is adjustably fastened in arm 54 vibrated through a connecting rod 55 by means of a crank pin 56 adjustably fastened to a crank disk 51 mounted on ashaft 58 supported in bearings of frame l5. Shaft 58 carries a sprocket 59 driven through a chain 68 by a. sprocket 6| mounted on shaft 25. On thelatter is mounted a ratchet 62 (Figs. 1 and 9) which engages a spring pawl 63 pivoted on an arm 64 loosely mounted on the shaft 25. To the hub of the arni 64 is attached a sprocket 65 which, through a chain 66, is driven by a sprocket 61 loosely supported by a shaft 68. To sprocket 61 is fastened a bevel gear 69 meshing with a bevel gear 18 mounted on the main shaft 1| of the wrapping machine. It is evident that the radial adjustment of the crank pin 56, while the arm 54 is unfastened from the flange 53, will permit the stroke of the grippers 36 and 31 to be varied in a corresponding degree and increase or diminish the length of sealing material fed thereby. This adjustment should be carried out only while the grippers are at rest in their central position.

The jaw 36 is fastened to a pair of collars 12 loosely mounted on a shaft 13 supported in bear ing lugs of guide block 38. One of the collars 12 is equippedwith an arm 14 having a lug which engages an adjusting screw 15 held by an operating lever 16, also loosely mounted on shaft 13. Between the arm 14 and operating lever 16 is inserted a compression spring 11 seated in sockets provided in the arm and lever and normally urging the same into positions in which the lug of arm 14 contacts the adjusting screw 15 on the operating lever. Lever 16 also carries aroller .18 which is periodically engaged by a horizontal cam or operating rail 19 fastened to a, pair of arms 89 mounted on an oscillating operating.

shaft 8| supported in bearings of frame l5. The leading end of the web S, by means of a bellmouth 82, is guided under the jaw 36 when the latter is opened, and is then gripped between the latter and a flange 83 (Fig. 4) extending from guide block 38, as will be presently described.

S by the paste wheel 29, and the jaws 36 and 31 are provided with grooves corresponding with the stripes in order to prevent fouling of the jaws with glue when they grip the web. Moreover, gummed paper may be-used for the sealing material, in which case the.paste reservoirv will be filled with water and the paste wheel will merely moisten the gummed surface of the web of sealing material. A flange 84 forming a part of the lug 85 projecting from guide block 39 underlies the jaw 31 and is provided with corresponding tongues to flt the notches of the flange 83, the latter coinciding with the notches of the jaw 36. Jaw 31 is fastened to collar 86 fixed on a shaft 81 supported in bearing lugs of block 39. On shaft 81 is fastened a lever 88 carrying a roller 89 which is engaged by the rail 19 during its upward movement to swing the jaw 31 to an open position. Lever 88 is equipped with a tension spring 98 anchored to the block 39 and acting to press the jaw 31 against flange 84. Operating lever 16 is likewise equipped with a tension spring 9| anchored to its block 38 and acting to press the adjusting screw 15 against the arm 14 and thereby swing the jaw 36 to an ineffective position, and also serving to keep roller 18 in constant engagement with rail 19. The latter is periodically raised while the jaw 36 is in its initial position, to lift the lever 16 and thereby permit the clamp 36 to close on the leading end of the web S, and the roller 18 rides on the rail while jaw 36 draws the web toward the center of the package. The contour of the rail 19 is designed to keep the jaw 36 closed during the descent of the rail 19 when the clamp reaches the center of the loaf, until the jaw 31 has closed on the leading end of the web wherefore the sameis gripped continuously. Thereupon the jaw 31 draws the leading end of the web from the center of the package to a point slightly beyond the end of the same.

After the desired length of web has been pulled underneath the package P in the manner just described, the operating rail 19 re-ascends and causes jaw 31 to open and jaw 36 to close upon a portion of the web remote from its leading end and, ascending further, operates a knife 92 which cuts off the desired length of strip S, the jaw 36 meanwhile holding the unsevered portion of the web S leading to the supply reel R. and spring 11 being slightly compressed by the movement of the lever 16 relative to the arm 14 at this time. The knife 92 is mounted on an arm 93 fastened to shaft 13. Arm 93 carries a roller 94 with whichthe rail 19 also engages during its ascent to operate the knife. A tension spring 95 connected to the arm 93 keeps the knife 92-out of the path of the web S except when raised as just described, during the cutting operation.

In order to keep the blocks 38 and 39 in an upright position during their reciprocating motion,

each block is equipped with a pair of bosses 96 straddling. the cross-shaft 49 and carrying on their lower ends guide rollers 91 engaging'with the sides of the cross-shaft (Figs. 3, 4, 7 and 8).

The practice of providing sealing strips with printed designs or labels for advertising purposes creates the necessity of cutting each strip to accurate length so that cumulative errors will not cause the web of sealing material to be cut at sections 'too close or too far from the printed matter thereon. In order to stop the feeding of the web S at the proper point, the latter is provided with equally spaced perforations or holes H- (Flg. 5) through which a contact disk 21a leads'90c and.90d connected to the coil of a solenoid 99 (Fig. 6). The latter in turn is energized and releases and operates a device, which will now be described, controlling the web-feeding and cutting mechanism. Contact disk 21a is pivoted on the free end of a forked arm I mounted on a shaft IOI supported in a bearing bra'cket I02 attached to one of the supporting with one arm of a bell crank lever I00 pivoted to frame I0. The upright arm of said bell crank lever I00 is provided at its end with an upright when a printed web is used. Cam III also has the function of operating the web-feeding and cutting mechanism in case the contact disk 210 should fail to make contact with the contact roller 21 due to an improper perforation or other arms 02. The core of the solenoid 99 is connected pin I04 which engages with a slot I05 of a control arm I00 loosely mounted on' the operating shaft 0I. The hub of arm I00 is provided with notches I0I (Fig. 1) into which project the Jaws I00 of a pair of clutch collars I00 fastened to shaft 0|. On the latter is fastened an arm IIO which Is connected by a link III to one arm H2 between the lug II'I and a wing nut on the end of the rod.

The electrical controlling device operates in synchronism with the mechanical means for oscillating the shaft 0|, whichcomprises the arm IIO actuated by cam IIO. The latter is designed to lift the rail 19 and thereby operate the webfeeding and cutting devices at the proper time and cut the sealer strip to the proper length, but the accumulation of errors, however small in the feeding of the web would result in appreciable errors in the spacing of the-printed designs or labels relative to the line of out without the electrical controlling device. The latter being actuated upon contact of the roller 21 and disk 210 through the accurately spaced perforations H, instantly operates the shaft 0I which in turn lifts the rail I9 to actuate the web-feeding and cutting members thereby assuring accurate feeding of the web. To this end the distance between the centers of; the perforations H is equal to the desired-length of the sealer strip. Each time a perforation If in the web S passes underneath the contact disk 21a, the latter makes contact with a contact roller 21, thereby closing the electrical circuit through the relay in the control box 90 and thereby energizing the solenoid 99 which, acting upon the bell crank lever I00,

causes the disengagement of pin I04 from slot I000! control arm I06 which, now released, is swung downward by the action of spring IIO acting upon the forked rod I I9 pinned to the arm.

This movementf the arm I00, through the engagement of one side of its notches with jaws I00 of the collars'I09, causes the shaft 0| to raise the rail I9- and close the gripper 00 on the web 8' and operate the knife 92 as heretofore described.

Cam lll'is provided for the purpose of operating the shaft 0I without the electrical controlling device in case a plain web of sealing material is used in this machine, wherefore the line of cut does not need to be so exactly spaced as.

cause. For this purpose the notches I01 in the hub of am 100 are made large enough to allow the jaws I00 of clutch collars I09 to move therein during turning of the shaft 0| without danger of injuring or breaking the electrical controlling device which locks the control arm I00. The cam I I5 is so timed that it resets the arm I00 to its-initial position after the bell crank lever has strip 8' against the bottom of the package P.

The pendant ends of the sealer strip. S are then folded-up and over the end folds of the package P by means of a pair of rotary folder fingers I22 having hubs. mounted on shaft 50 and acting to wipe the endsof the sealer strip over the guide strips22. The hubs of the folders I22 are fasttened to the shaft 00 by set screws, wherefore they may be moved inwardly thereon after the set screws are loosened, to accommodate packages of various lengths. The arm I2I is fastened to a shaft 00 which carries a cam lever' I20 provided with a cam roller I24 engaging with a cam groove of face cam I25 mounted on shaft 50. Arm I2I is also equipped with an extension I26 which is connected by link I21 with one arm I20 of the operating lever 20 which actuates the bottom guide rails 20. This hook-up assures advance are first tilted downwardly to clear the J sealer strip, and then come =;.to rest in an upwardly tilted position whereby the sealed package is raised slightly above the guides 20 to permit delivery thereof to the guides without injury rto the sealer strip. Thereupon a new package is pushed into sealing position by the next pair of arms II' whereby the finished sealed package is pushed on to the delivery guide rails 2I fastened to the delivery table I29 attached to frame I0, the ends of the sealer strip which were previously wiped over .the guide strips 22 being drawn off the latter during this movement of the package. Table I29 also carries a pair of side guide rails I00 extending almost to the sealing station of the machine to press the ends of the pasted sealer strip S against the package while drying. Platform extensions" are equip with a number of hooked leaf springs III (Figs. 1 and 6) tends into the path of the package advancing into the sealing position. The feeler "2 has a hub 333 mounted on a cross shaft I34 supported in bearings of frame l5. Shaft B4 carries a gear segment 35 engaging with a gear segment 536 mounted on shaft I31 held by frame It. Shaft l3! carries an arm I38 to which is pivoted a roller I39. When no package arrives the feeler 332 will maintain its upright position, wherefore the roller I39 on arm I38 will remain in the path of the pawl 63 on the arm 64 and disengage pawl 53 from the ratchet 62, thereby stopping shaft 25 and therewith the entire strip sealer. The package P, when delivered to the sealing station presses detector finger I32 downward, causingarm I 38 to swing the roller I39 out of the path of the spring pawl 63 so that the strip sealer can operate without interruption.

The invention is not to be restricted to wrapped packages having end folds and a bottom seam, as the present construction can evidently be used to band cartons, etc., or seal various types of packages.

What is claimed is:

1. In a strip sealer, the combination with means for supporting in an upright position at a sealing station a package having a bottom seam and end folds in its wrapper, of mechanism for applying a strip of sealing material over saidbottom seam and end folds only, to seal the same,

. said mechanism comprising devices for feeding an adhesive sealer strip lengthwise relatively to said folds, and devices for pressing said strip against the folds.

2. In a strip sealer, the combination with means for supporting in an upright position a package having a bottom seam and end folds in its wrapper, of mechanism for applying a strip of sealing material over said bottom seam and end folds only to seal the same, said mechanism including means for drawing a web of sealing material under the bottom of the package and severing a sealer strip of the required length from the web, a member for applying stripes of paste to said web, and devices for pressing the pasted sealer strip against the bottom seam and end folds of the package.

3. In a strip sealer, the combination with means for supporting in an upright position a package having a bottom seam and end folds in its wrapper, of mechanism for applying a strip of sealing material over said bottom seam and end folds only to seal the same, said means including two sets of opposed stationary members having a gap between their adjacent ends and adapted to support the bottom of the package, and said mechanism including means for drawing a web of sealing material along said gap and severing a sealer strip of the required length from said web, and a device for pressing the sealer strip against the bottom seam through said gap.

4. In a strip sealer, the combination with stationary' members for supporting in an upright position at a sealing station a package having end folds in its wrapper, of mechanism for applying a strip of sealing material over the bottom and end folds only of the package, said mechanism comprising devices for feeding an adhesive sealer strip lengthwise relatively to said folds, and devices for pressing said strip against the folds.

5. In a strip sealer, the combination with means for supporting in an upright position a package having a bottom seam and end folds in its wrapper, of mechanism for applying a strip of sealing material over said bottom seam and end folds only to seal the same, said means including two sets of opposed stationary members having a gap between their adjacent ends and adapted to support the bottom of the package, and said mechanism including means for drawing a web of sealing material along said'gap and severing a sealer strip of the required length from said web, a device for pressing the sealer strip against the bottom seam through said gap, said mechanism including means for drawing a web of sealing material under the bottom of the package and severing a sealer strip of the required length from the web, and devices for pressing the severed strip against the package. I

6. In a strip sealer, the combination with means for supporting in an upright position at a sealing station a package having a bottom seam and end folds in its wrapper, of electrically controlled means for drawing a printed web of sealing material under the bottom of the package to bring the printed matter thereon in predetermined relation with the package, means for applying stripes of paste to the upper face of the web, a cutter for severing a sealer strip from the portion of the web underlying the package, and devices for pressing the pasted sealer strip against the bottom and end folds of the package into adhering relation therewith. 1

'7. In a strip sealer, the combination with means for supporting a wrapped package having a bottom seam in its wrapper in upright position at a sealing station with said bottom seam exposed, of mechanism for applying a sealer strip to said seam in adhering relation therewith, said mechanism comprising devices for feeding an adbottom and end folds of the 'hesive sealer strip lengthwise relatively to said folds, and devices for pressing said strip against a device for delivering the wrapped articles in upright position at a sealing station, of mechanism for applying a sealer strip to said bottom seam and end folds in adhering relation therewith, said mechanism comprising devices for feeding an adhesive sealer strip lengthwise relatively to said folds, and devices for pressing said strip against the folds.

9. In a wrapping machine wherein articles are enveloped in a wrapper folded to produce a bcttom scam, the combination with a device for delivering the wrapped articles in upright position at a sealing station, of stationary members having a gap therebetween for supporting in upright position the packages delivered by said device, and mechanism for applying a strip of sealing material over the bottom seam of the package supported on said means, said mechanism comprising devices for feeding 'said sealing strip lengthwise relatively to said bottom seam, and devices for pressing said sealing strip thereagainst.

10. In a wrapping machine wherein articles are enveloped in a wrapper folded to produce a bottom seam, the combination with a device for delivering the wrapped articles in upright position, of stationary members having a gap therebetween for supporting in upright position the packages delivered by said device, mechanism for applying a strip of sealing material over the bottom seam of the package supported on said means, said mechanism including means for 7 drawing a web 'of sealing material along said gap and severing a sealer strip of the required length from said web, a member for pressing the age delivered .by said device.

11. The combination with stationary members having a gap therebetween and adapted to support a wrapped package having a bottom seam,

of a device for applying a sealer strip to said bottom seam through said gap, and means for thereafter slightly tilting the package upwardly on said members to permit the package to be advanced on said members without injury to the sealer strip applied to the bottom seam.

12. In a wrapping machine wherein articles are enveloped in a wrapper having its margins lapped on the bottom of the article in the form of a bottom seam, the combination with stationary members having a gap therebetween and arranged to support a package in upright position, of devices for advancing the packages on to said members, and means for bridging said gap while a package is being moved over the gap while being delivered to said members.

18. In a wrapping machine wherein articles are enveloped in a wrapper having its margins lapped on. the bottom of the article in the form of a bottom seam, the combination with stationary members having a gap therebetween and arranged to support a package in upright position, of devices for advancing the packages on to said members, means for bridging said gap while a package is being moved over the gap while being delivered to said members, and mechanism for thereafter retracting said means and pressing a sealer strip through said gap against the bottom seam of the package supported on said members.

14. In a wrapping machine wherein articles are enveloped in a wrapper folded to produce a bottom seam and end folds, the combination with means for advancing the packages to' sealing position, of members arranged to hold the end folds of the packages against the ends of ar ticles during their movement to sealing position, and mechanism for applying a sealer strip to the bottom seam and end folds of the packages at the sealing position.

15. In a wapping machine wherein articles are enveloped in a wrapper folded to produce a bottom seam .and end folds, the combinationwith means for advancing the packages to sealing position, of members arranged to hold the end folds of the packages against the ends of articles during their movement to sealing-position, and mechanism for applying a sealer strip to the bottom seam and end folds of the packages at the sealing position, said mechanism including a set of folders acting to wipe the ends of the sealer strip over saidmembers and against said and folds. .1

16. In a wrapping machine, the combination with a device for advancing into predetermined sealing position a package having a bottom seam, of mechanism set into operation by the package being advanced to sealing position for applying a sealer strip to the bottom seam of the package, said mechanism comprising devices for drawing a sealing strip longitudinally along said bottom seam in said sealing position, devices for pressing said strip against said seam, and means to actuate said devices while said package is' at rest insaid' sealing position. 17. In a wrapping machine, the combination the bottom seam of the package at sealing posiwith a device for advancing into predetermined sealing position a package having a bottom seam,

- of mechanism set into operation by the package with a device for advancing into predetermined sealing position a package having a bottom seam. and end folds, of mechanism set into operation by the package being advanced to sealing position for applying a sealer strip to the bottom seam and end folds of the package, said mechanism 7 comprising devices for drawing a sealing strip longitudinally along said bottom seam in said sealing position, devices for pressing said strip against said seam, and means to actuate said devices while said package is at rest in said sealing position.

19 In a wrapping machine, .the combination with a device for advancing into predetermined sealing position at a sealing station a package having a bottom seam and end folds, of mechanism set into operation by the package being advanced to said sealing position for applying a sealer strip to the bottom seam and end folds of the package, said mechanism including mmns operating to draw a web of sealing material under tion and sever a sealer strip from the web, and means for applying the severed strip to the bottom seam and end folds of the package, said mechanism comprising devices for drawing a sealing strip longitudinally along said bottom seam in said sealing position, devices for pressing said strip against said seam; and means to actuate said devices while said package is at rest in said sealing position.

20. In a wrapping machine, the combination. with a device for advancing a package into predetermined sealing position, of mechanism set into operation by the package'being advanced to sealing position for applying a sealer strip to the package, said mechanism comprising devices for 0 drawing a sealing strip longitudinally along said bottom seam in said sealing position, devices for pressing said strip against said seam, and means to actuate said devices while said package is at rest in said sealing position.

21. The combination with a device for advancing a package into sealing position, of two sets of grippers, and mechanism for actuating each set of grippers to successively seize the leading end of and advance a web of sealing material under the bottom of the package at sealing position. a

22. The combination with a device for advancing apackage into sealing position, of two sets of grippers, and mechanism for actuating each set as of grippers to successivelyseize the leading end of and advance a web of sealing material under the bottom of the package at sealing position, said mechanism causing the first set of grippers to release the web intermediate the ends of the 7 .package and causing the second set of grippers to selze'the leading end of the web before the same is released by theflrst set of gripp rs and -.thereai'ter further advancing the web.

23.' The combination with a device for advanc- J0 ing a package into sealing position, of two sets of grippers, and mechanism for actuating each set of grippers to successively seize the leading end of and advance a web of sealing material under the bottom of the package at sealing position, and a knife carried by the first set of grippers and actuated by said mechanism to sever a sealer strip from the web.

24. In a strip sealer, the combination with means for supporting in an upright position at a sealing station a wrapped package having a bot.- tom seam and end folds in its wrapper, of mecha-' nism for applying a strip of sealing material over said bottom seam and end folds only, to seal the same, said mechanism comprising two sets of gripper devices for feeding an adhesive strip lengthwise relatively to said folds, and devices for pressing said strip against the folds; said sealer having means to advance the package to a sealing position for said application of the sealing strip, sensing means operable in the path of the package as it approaches said sealing position, and means for incapacitating the sealing mechanism, said last-named means being made effective by said sensing means in the absence of a package in the path to said sealing position at the appropriate stage of the machine cycle, and said sensing means being moved, by due approach of a package in the path to said sealing station, to render said sealing mechanism effective in due course. 4

25. In a strip sealer, the combination with means for sup rting in an upright position at a sealing station, a wrapped package having a bottom seam and end folds in its wrapper, of mechanism for applying a strip of sealing material over said bottom seam and end folds only, to seal the same, said mechanism comprising two sets of reciprocating gripper devices cooperating to pull the leading end of a strip of sealing material into sealing position at the sealing station, one of said gripping devices having means connected therewith to sever each sealing strip from the web upon return of said last-named gripper to its initial gripping position preparatory to feeding the next sealing strip.

26. In a strip sealer, the combination with mechanism for advancing a package having a wrapper formed with a bottom seam an end folds, means to hold the folded wrapper ends in snug disposition for application thereto of a sealer strip, and mechanism for applying said sealer strip exclusively to said bottom seam and end folds while so held, said mechanism including means to press the strip ends individually against the and folds after advancement of the package beyond the range of said end-holding means.

27. In a. strip sealer, the combination with means for supporting in an upright position a wrapped package having a bottom seam and end folds in its wrapper, of mechanism for applying a strip of sealing material over said bottom seam and end folds only to seal the same, said mechanism including means for drawing a web of sealing material of indefinite length under the bottom of the package, and severing a sealer strip of the required length from the web, means to adjust said severing means to part sealing strips of various lengths from the web, and adjustable devices for applying a sealer strip adheringly in proper position, according to its length when so severed, against the bottom seam and end folds of the package.

f ANTON VAN VEEN.

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