US2566799A - Rotary sealer - Google Patents

Description

Sept. 4, 1951 J. M. HUMPHREY- ROTARY SEALER 6 Sheets-Sheet 1 Filed Nov. '7, 1946 J- M- HUMPHREY KI'TORNEY Sept. 4, 1951 Filed Nov. '7, 1946 J. M. HUMPHREY ROTARY- SEALER 6 Sheets-Sheet 2 INVENTOR. J. M. HUMPHREY 2 KTTORNEY P 1951 .1. M. HUMPHREY 2,566,799

ROTARY SEALER Filed Nov. '7, 1946 6 Sheets-Sheet 4 10., in mlh g 1% FIG. 5

INVENTOR.

J M HUMPHREY ATTORNEY Patented Sept. 4, 1951 UNITED STATES PATENT OFFICE 8 Claims.

This invention relates to improvements in devices for sealing the open ends of bags, particularly bags formed of scalable material such as cellophane, or other heat softenable or heat moldable material, and is especially directed to improved means for feeding the bags into and away from the bag sealing device.

The sealing device itself may be such as is particularly illustrated and described in my prior application Serial Number 643,631, filed June 26, 1946, for Rotary Type Heat Sealer, now abandoned, to which reference may be had for a detailed description of the sealer mechanism.

Since this type of sealer has been in use many attempts have been made to provide automatic feeding means to carry the filled bags to be sealed to and away from the sealing rollers.

These various attempts have failed to provide a satisfactory mechanism, the chief difficulty having been encountered in feeding the bag ends into the sealing rollers. In the prior device the bag ends have been brought to the vicinity of the location at which the rollers most nearly contact each other and the gripping action of the rollers has then been depended upon to carry the bag ends between them. This has resulted in imperfect closing and sealing of the bags since the bag ends are frequently presented to the sealing rollers in a crumpled or creased condition, or at an angle to the plane of rotation of the rollers or not at the proper height for perfect sealing. There is also a tendency in the previ-. ously used feeding devices for the bag ends to slip or turn as they are passing through the rollers and for an occasional bag to adhere to one of the rollers and be carried by the roller away from the feeding mechanism.

It has also been found difficult to maintain the moving parts of the feeding mechanism in exact synchronism with the turning of the sealing rollers.

At the same time it is highly desirable to provide a substantially automatic feeding device for such a sealer to increase its efficiency and speed of operation, reduce the necessary amount of manual labor and provide more perfect seals,

It is therefore among the objects of the present invention to provide an improved rotary type bag sealer having bag feeding mechanism which will firmly grip the bags at a location convenient to the operator of the sealer and hold the bags in firmly gripped condition until they have passed between the sealing rollers and will support the bags on movable conveyor means as they approach and leave the sealing rollers.

A further object resides in the provision of improved feeding means for a rotary type bag sealer which is fully adjustable to maintain the proper pressure on the bags as they are fed between the sealing rollers.

A still further object resides in the provision of improved feeding means for a rotary type bag s aler in which the movable portions of the feeding means are operatively connected with the sealing rollers in a manner such that the feeding means is driven in exact synchronism with the sealing rollers.

Another object resides in the provision of improved feeding means for a rotary type bag sealer which feeding means is simple and economical to manufacture and install and durable in operation.

Other objects and advantages will become apparent from a consideration of the following description in conjunction with the accompanying drawings in which:

Fig. l is a perspective view of a rotary type bag sealer showing automatic feeding means il-- lustrative of the invention applied thereto;

Fig. 2, a perspective view of the lower portion of the sealing machine and the automatic feeding means with the covers removed from they automatic feeding means to show the construction thereof;

Fig. 3, a side elevational view of a complete bag sealing unit including a supporting tabie with a conveyor belt thereon, a rotary type sealing machine mounted above the table and an automatic feeding device for the sealing ma chine;

Fig. 4, a top plan view of a fragmentary portion of the table shown in Fig. 3, parts being broken away to better illustrate the construction thereof;

Fig. 5, a bottom plan view on an enlarged scale of the automatic feeding device for the rotary sealer;

Fig. 6, a transverse sectional view on the line 66 of Fig. 5; V

Fig. '7, a transverse sectional view on the line 1-1 of Fig. 5;

Fig. 8, a sectional view on an enlarged scale of a modified sealing roller adapted for the application of the automatic feeding means thereto;

Fig. 9, a view similar to Fig. 8 showing a further modified form of sealing roller; and

Fig. 10, an elevational view on an enlarged scale showing a fragmentary portion of one of the feeding chains of the auto'inatic feeding mechanism.

With continued reference to the drawings, the

heat sealing machine comprises, in general, a tubular vertical column III having a. flange II at its lower end by means of which the standard or column III may be rigidly secured to the top of a suitable support, such as the table, generally indicated at I2. A tubular sleeve I3 is vertically slidable on the standard In and has secured thereto a gear casing I4 from the bottom of which depend two vertical shafts I5 and IS on. the lower end of which the sealing rollers I1 and I8 are respectively secured, these rollers being enclosed in the guard shield or cover I! shown in Fig. 1 but being illustrated in bottom plan view in Fig. 5.

Below the gear casing I4 and immediately above the heat sealing rollers I1 and I8, a hearing bracket extends outwardly from the sleeve I3 and the roller shafts I5 and I6 pass through this bracket and-are Journalled therein, suitable means being associated with the bracket to, vary the pressure exerted between the two rollers. Between the bearing bracket 20 and the gear casing I4 a switch bracket 2i is secured to the sleeve I3 and extends outwardly to locate the operating switches for the machine at a position convenient to the operator. One of these switches, for example the switch 22, may be connected to control the drive motor of the sealing machine. Another switch, such as 23, may be connected to control the heating ofthe sealing rollers and a third switch 24 may be connected to control the heating of the preheating elements 25 and 26 through which the bags pass before passing between the sealing rollers. The preheating means and the roller heating means are suflicient to soften the material of the bags to an extent such that when the sides of the open end portions of the bags are pressed together by the sealing rollers, these sides will permanently adhere to each other providing a substantially airtight seal for the bag. The bags 7 are ordinarily made of cellophane or some similar heat softenable material.

Above the gear casing I4 a motor bracket 21 is secured to sleeve I3 by an adjustable connection which includes the set screw 28. A drive motor 29 is mounted on the upper surface of bracket 21 and connected by a suitable drive belt 30 with a drive shaft extending from the gear casing I4.

The distance between the sealing rollers and the top surface of the table or support I2 is controlled by adjusting means including the cable 3| which passes over a sheave 32 at the upper end of column III and is wound on a winch or Windlass 33 having a manually operable crank 34 for raising and lowering the sleeve I3 and a the mechanism carried thereby, on thestandard I0. By this arrangement the sealing machine may be adjusted to seal bags of different heights.

An automatic bag feeding device, generally indicated at 35, is attached to the, lower portion of the bag sealing machine and operatively associated with the sealing rollers. This feeding device is operativeto grasp the upper ends of bags, as indicated at 36. moved along a conveyor belt 31 carried by the table I2 and to carry said bags through the sealing machine in a position such that the bags will be uniformly sealed over a sufficient area to provide a substantially air-tight and moistureproof seal for each bag.

The support or table I2, as is particularly illustrated in Figs. 1 and 3. has an upper surface portion 38 upon which the machine standard II is secured and which extends from each of two opposite sides of the standard location. Along one edge thereof the table is provided with a longitudinal depression 39, the outer side of which is constituted by a cover plate 40 of sheet metal or some similar relatively thin material. The conveyor belt 31 runs in the depression 39 and is driven by suitable mechanism, including the drive motor 4|, the reduction gear unit 42, the belt pulley 43, and the v-belts 44 and 45. The motor and reduction gear unit may be conveniently supported on a table shelf 46 disposed between the center legs 41 and one set of end legs 48 and reinforced by suitable braces 49 and 50. A set of end legs 5I supports the end of the table opposite the end supported by the legs 48.

With this arrangement bags, as indicated at 36 in Fig. 3, may be placed upon the conveyor belt 31 at one end of the table I2 and the conveyor belt will carry the bags to the receiving end of the automatic feeding mechanism 35, which mechanism will carry the bags through the sealing machine. As the bags pass through the sealing machine, they are continuously supported on the conveyor belt 31, and as they leave the machine the belt carries the sealed bags away from the machine as indicated at 36' in Fig. 3. The speed of the conveyor belt 31 is synchronized with the speed of the automatic feed device 35 so that the bags will not be tilted or upset as they pass through thefeed mechanism and the sealing machine but will retain a substantially vertical po-, sition on the conveyor belt and will be sealed over substantially uniform areas by the sealing machine.

This combination of supporting table, conveyor belt, and drive means therefor, automatic feeding device and rotary sealing machine, provides a substantially automatic bag sealing apparatus, the use of which requires only the placing of the bags on the conveyor belt at one end of the table and the removal of the sealed bags from the conveyor belt at'the discharge end of the table.

The improved automatic feeding mechanism is particularly illustrated in Figs. 2 and 5 to 10,

inclusive. This mechanism comprises a pair of flat arms 52 and 53 secured to the under side of the bearing bracket 20. In order to position these arms at the level of the lower ends of the corresponding sealing rollers I1 and I8, each arm is provided with a substantially Z-shaped end portion, as indicated at 54 for the arm 52 and at 55 for the arm 53. As is particularly illustrated in Fig. 2 in connection with the arm 53, the upper substantially horizontal part of the Z-shaped end portion 55 is secured to the under surface of bearing bracket 20 by suitable means, such as the bolt 56. The substantially vertical part of the Z-shaped end portion extends downwardly from the end of the horizontal portion past the sealing roller n to the level of the bottom end of the sealing roller and from the bottom end of the vertical part a substantially horizontal arm portion 51 extends away from the roller. The lower horizontal parts of the arms 52 and 53 have sub--' stantially parallel edges adjacent the respective Z-shaped end portions but have inwardly tapered outer edge portions at their outer ends, as is clearly illustrated in Fig. 5. The inner edge portions of the two arms are straight. parallel and opposed but spaced apart as is also clearly shown 'in Fig. 5. At its outer end the arm 52 carries a chain sprocket 58 journalled on an axle 59. the lower end of which is fixed in the outer end portion of the arm and the arm 53 carries a similar chain sprocket 60 journalled on an axle 8| carried by the arm. The two sprockets 58 and 69 are disposed in the same substantially horizontal plane and rotate in close proximity to each other but without interference between them.

Each of the sealing rollers I1 and I8 is made somewhat longer in its vertical dimension than the corresponding rollers shown in application Ser. No. 643,631 referred to above, and each roller has a chain sprocket on the bottom end thereof. In the arrangement shown in Fig. 8 wherein the construction of the roller I8 is shown in de-- tail, the two rollers being of the same construc tion, roller I8 is provided with an annular recess 82 located between an apertured central boss 63 which receives the lower end of drive shaft l6,

and a concentric peripheral rim G4, the outer surface of which is preferably grooved, knurled, or otherwise treated to rovide a roughened surfaced, as indicated at C5. Roller heating elements 68 are disposed in the recess 52 and below these heating elements the bottom wall 61 connects the central boss with the rim 54. This wall 61 is made sufliciently thick so that chain sprocket teeth 68 may be provided thereon. may be conveniently provided integrally with the roller by cutting a groove 69 in the cylindrical surface of the roller adjacent the bottom end thereof to provide a ridge or head 19 and then machining the ridge or bead T9 to provide the separate sprocket teeth 68. The efiective diameter of the sprocket having the teeth 68 is such that the speed of a feed chain driven by said sprocket is exactly the same as the peripheral speed of the corresponding roller.

In the modified arrangement shown in Fig. 9 the roller 18 is of the same size and construction as the sealing rollers shown in my prior application referred to above, and a sprocket member ll is formed from a flat metal plate having sprocket teeth 68 cut into the periphery thereof. This plate may be attached to the bottom end of the roller by suitable means such as screws 12 extending through the plate and into the bottom wall 81 of the roller.

While the roller-carried chain sprocket may be provided by either of the above-described methods, it has been found that certain factors favor the provision of the chain sprocket integral with the roller, as illustrated in Fig. 8, as this method provide a sprocket which is truly concentric with the roller and cannot become loosened or slip relative to the roller, has the same heat expansion and contraction characteristics as the remainder of the roller, and substantially the same wearing characteristics.

For the sake of simplifying the description the sprocket for the roller IT has been indicated by the numeral 12 in Fig. 5 and the similar sprocket for the roller I8 has been designated by the numeral 13, these references being applied without regard to the manner in which the sprocket is provided.

An endless flexible member, such as the chain generally indicated at T4, surrounds the sprocket I2 on roller l1 and the sprocket 58 at the outer end of arm 52 which extend outwardly frgm the roller I I. A similar member, general indicated at 15, surrounds the sprocket 13 on roller 18 and the sprocket 69 at the outer end of arm 53 which extends outwardly from roller l8. Between the sprocket l2 and the sprocket 59 a guide sprocket 16 is journalled on an extension 11 of arm 52 to guide the outer flight of chain 14. Between this guide sprocket and sprocket I2 an idler These teeth sprocket l8, journalled on the outer end of an arm 19, the inner end of which is pivotally mounted on the arm 52 by a pin 80, bears on the outer side of the outer flight of chain 14 and is resiliently urged into chain-tightening contact with the outer flight of the chain by a coiled tension spring 8|, one end of which is secured to the outer end of arm 19, the opposite end of which is secured to arm 52 adjacent the roller IT. A guide sprocket 82 mounted on extension 83 of arm 53 guides the outer flight of chain 15 and idler sprocket 84 journalled on the outer end of'arm 85, the inner end of which is pivotally mounted on arm 53 by pin 86, is held in chaintightening contact with the outer flight of chain between sprockets 82 and 13 by coiled tension spring 81, one end of which is secured to the outer end of arm 85, and the opposite end of which is secured to arm 53 adjacent roller l8.

As is clearly illustrated in Fig. 5, the inner flights 88 and 89 of chains 74 and 15,.respeclively, are parallel and opposed between the inner edges of the supporting arms 52 and 53. These inner flights of the chains are resiliently urged into contact with each other by spring pressed chain guide members 99 and 9|.

As clearly shown in Fig. 6, the chain guide member 9] comprises a flat plate rigidly secured to arm 53 by suitable means, such as bolts one of which is indicated at 92. This plate overlaps the upper surface of arm 53 and has its edge which extends beyond the inner edge of arm 53 in contact with the outer side of the inner flight 89 of chain 15. The guide 90 also comprises a flat plate which overlaps the upper surface of arm 52 and has its edge positioned beyond the inner edge of arm 52 in contact with the side of the inner flight 88 of chain 14. The guide 90 is held in contact with the arm 52 by suitable means, such as pins 93 and 94 extending through the arm and through respective slots in the guide 90 and provided with heads overlying the upper surface of the guide adjacent the slots. This construction permits the guide 99 to slide on the upper surface of the arm 52 a small amount toward and away from the opposed edge of guide 9|. Near its outer end the guide 99 is provided with an upstanding portion 95 at its outer edge, this portion 95 being provided with an extension 96 which receives a corresponding end of a coiled compression spring 91, the opposite end of which bears against the inner surface of a bracket 98, of angular shape, which extends across the outer end of arms 52 and 53 to support the feeder cover, one-half portion of which is shown in Fig. 6 and indicated at 99. A screw I00 threaded through the bracket 98 enters the end of spring 91 to hold the spring in proper operative position. This spring resilienty urges the outer end of spring guide member 90 against the inner flight 88 of chain 14 to force this chain inner flight against the inner flight 89 of chain 15 with a predetermined resilient pressure. At its end adjacent the roller ll the guide member 99 is urged inwardly by a coiled compression spring |9l which is disposed in a tubular retainer I02 welded or otherwise secured to the arm 53 between the roller l1 and adjacent surface of the vertical part of the Z-shaped arm prrtion 55.

One end of the spring lfll bears against an upstanding lug I93 provided on the guide 90 at i s outer edge and the opposite end of the spring bears against a screw plug I04 threaded into the outer end of the spring retainer I02. The pressure of the spring l0! on the guide 90 may be -Flg. 10. Such chains comprise solid connectors,

as indicated at I05, and parallel side plates, as indicated at "6. the connectors and side plates being pivotally united by pins lll extending through apertures in the end portions of the side plates and solid connectors. In order to particularly adapt this type of chain to the feeding operation described above, the side plates I06, are

ground of! flat around one side, as indicated at III in Fig. 10, so that the chains present flat opposed surfaces between the inner flights thereof, which surfaces will grip and firmly hold the upper ends of the bags without puncturing or tearing the material of which the bags are formed.

The arms I! and 53 are so arranged that the inner flights of the chains extend along the conveyor belt 31 toward the feed end of the table so that the chains will receive the bags moved toward the sprockets 58 and 60 by the conveyor belt and carry the bags from this point entirely through the bag sealing machine and discharge the sealed bags at the discharge side of the machine onto the conveyor belt from which they may be conveniently removed.

The preheating elements 25 and 26 are supported on the corresponding arms 52 and 53 by suitable angle brackets, as indicated at I09 and Ill, and the feed cover parts 99 and iii are supported at their outer ends on the bracket I and at their inner ends on the Z-shaped end portions of the arms 52 and 53. A retaining plate 2 secured to bracket 98 and overlying the cover parts secures the cover parts to this bracket and a somewhat similar plate 3 secured to the Z- shaped end portions of the arms and overlying the parts of the cover secures the cover parts to the Z-shaped end portions of the chain supporting arms. Between the cover portions 89 and Hi a removable cover portion Ill covers the manual adjusting device H5 which controls the rheostat iii of the preheating elements an 20.

Additional outer end chain guards Ill and 8 are secured to the outer end portions of the arms i2 and 53 by suitable fastening means such as the bolts 9 and enclose the outer sprockets 58 and .0 and the outer portions of the chains to maintain these parts free of dirt and debris and avoid danger of inJury to the operator.

It will be obvious to those skilled in the art that'various changes may be made in the invention without departing from the spirit and scope thereof and therefore the invention is not limited by that which is shown in the drawings and described in the specification but only as indicated in the appended claims.

What is claimed is:

1. In combination with a bag sealing machine having a pair of opposed sealing rollers and means for driving said rollers; automatic bag feeding means for said machine comprising a.

pair of arms mounted on said machine and extending outwardly therefrom at the level of said rollers; a sprocket on the outer end of each arm; a sprocket on the lower portion of each roller; a pair of endless chains each surrounding one roller sprocket and the sprocket at the outer end of the corresponding arm, the inner flights of said chains being parallel and opposed and driven at the same speed toward said rollers by said roller '8 sprockets; and means carried by said arms guiding the inner flights of said chains and maintaining an adjusted pressure between said inner chain flights.

2. In combination with a bag sealing machine having a pair of opposed sealing rollers and means for driving said rollers; automatic bag feeding means for said machine comp ising a pair of arms" mountedi-oh said machine and extending outwardly gt'herefrom at the level ofsaid rollers; a sprocket on the outer end of each arm; a

sprocket on the lower portion of each roller; a

pair of endless chains eachsurrounding one roller sprocket and the sprocket at the outer end of the corresponding arm, the inner flights of said chains being parallel and opposed and driven at the same speed toward said rollers by said roller sprockets; means carried by said arms guiding the inner flights of said chains and maintaining an adjusted pressure between said inner chain flights; and spring loaded chain tightening means carried by said arms and operatively engaged with said chains.

'3. In combination with a bag sealing machine having a pair of opposed sealing rollers and means for driving said rollers; automatic bag feeding means for said machine comprising a pair of arm mounted on said machine and extending outwardly therefrom at the level of said rollers; a sprocket on the outer end of each arm, a sprocket on the lower portion of each roller; a pair of endless chains each surrounding one roller sprocket and the sprocket at the outer end of the corresponding arm, the inner flights of said chains being parallel and opposed and driven at the same speed toward said rollers by said roller sprockets; means carried by said arms guiding the inner flights of said chains and maintaining an adjusted pressure between said inner chain flights; and an additional chain guide pulley carried by each arm and operatively engaged with the corresponding chain.

4. The combination as deflned in claim 1 wherein each of said endless chains is provided with a flattened outer side to grip the material of bags to be sealed without puncturing or otherwise inJuring the material.

5. The combination as deflned in claim 1 wherein the sprocket on the lower end of each sealing roller i integral with the corresponding roller.

6. The combination as defined in claim 1 wherein said chain guide means comprise a pair of flanged members secured one to each arm along the inner flight of the corresponding chain, a

and adjustable spring means operatively connected between one of said members and the corresponding arm to adjust the pressure exerted between the inner flights of said chains.

7. The combination a defined in claim 2 wherein the tightening means for each chain comprises an arm pivotally secured at its inner end to the corresponding chain carrying am; an idler sprocket journalled on the outer end of said pivoted arm and engaging the outer flight of the corresponding chain; and a spring acting between the outer end of said pivoted arm and said corresponding chain carrying arm.

8. Bag sealing apparatus comprising an elongated table having a lengthwise depression along one side thereof; a rotary bag ealing machine mounted on said table above said depression and having a pair of opposed bag sealing rollers; a conveyor belt in said table depression; a pair oi arms each supported at one end on said ma- 9 chine and extending to one ide of said machine along said table depression; a chain sprocket at the outer end of each arm; a chain procket on the lower end of each sealing roller; a pair of endless chains each surrounding one roller 5 sprocket and the sprocket at the outer end of the corresponding arm, the inner flights of said chains being parallel adjacent and opposed to grip the upper end of bags carried along said conveyor belt and feed them between said sealmg rollers; and means driving said conveyor belt at a speed in synchronism with the speed of said has feeding chains.

JAMES M. HUMPI-EREY.

REFERENCES CITED The following references are of record in the I file of this patent:

UNITED STATES PATENTS OTHER REFERENCES Doughboy, published by Dairyland Farmer Press, New Richmond, Wis., available to the public in Dec. 1943.

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