JP2002516789A - Tamper-resistant closure - Google Patents

Abstract

SUMMARY OF THE INVENTION A method and apparatus for forming a tamper-resistant seal in a plastic bag containing bread loaves and other products is disclosed. The neck (125) of the bag (125b) is flattened and a pair of upper inboard and outboard gathering belts and a pair of lower inboard and outboard gathering adjacent the opposing sides of the bag neck segment. I get caught between the belt. As the bag moves adjacent to the rollers provided with teeth or cutting elements, a row of perforations (132) is formed in the neck of the bag. Inboard and outboard to form a sealed strip spaced from the perforation row of the bag neck and to weld the bag panels so that the sealed strip can be easily removed from the bag. A jet of heated air is directed into engagement with a segment of the bag spanning between the gathering belts.

Description

DETAILED DESCRIPTION OF THE INVENTION

TECHNICAL FIELD This invention relates to a tamper-resistant closure attachment to a device for wrapping a ribbon around the pursed neck of a bag and twisting the ribbon to close and seal the neck of the flexible bag. About the machine. BACKGROUND ART U.S. Pat. No. 3,138,904 (title of the invention: method and apparatus for tying package and wrap material) and U.S. Pat. No. 3,059,670 (title of the invention: wire twisting device)
U.S. Pat. No. 3,919,829 (device for tying package and wrap material); U.S. Pat. No. 4,856,258 (title of invention: wire binding device); and U.S. Pat. Device Ribbon Sensing Device discloses a device used to attach a wire ribbon around the neck of the bag and twist it to close the plastic bag.

A bag tying device of the type disclosed in the aforementioned patent is disclosed in Oklahoma,
Available from Buford Corporation, Maysvill. The tying device is typically configured to receive a package such as a loaf of bread at a rate of producing, for example, 100 or more packages per minute at a rate of about 108 feet / minute.

[0003] Plastic bags containing bread products, paper pieces, and ice can be easily opened to access the contents of the bag by removing the twisted ribbon around the neck of the bag. The bag can be resealed by hand by repositioning the ribbon around the neck of the bag and twisting it.

[0004] US Pat. No. 5,600,938 discloses an apparatus for sealing a plurality of spaced apart points across a flattened open end of a plastic bag containing contents. The bag is moved along the conveyor past a sealing mechanism that welds a plurality of spaced apart locations across the open end of the bag. In one embodiment, the sealing mechanism includes a plurality of heated pins extending through the two layers at the open end of the bag while substantially flattening the end of the bag. These pins then move with the bag in synchronism with the conveyor while welding. In another embodiment, the sealing is performed using a wheel with heated pins around it, the wheel rotating so that its tangential speed is synchronized with the conveyor, and in turn, at spaced welding points. Is formed across the substantially flattened open end of the bag. This device was designed to allow the bag to be opened without tearing or breaking the bag, while carefully sealing the bag to show evidence of tampering by breaking the seal. Seal the separated area.

US Pat. No. 5,741,075 describes a package having a flexible plastic bag and a label. The bag has a closed end that can be opened to create an opening to access the contents of the package. The closed end of the package is first sealed in a sealing area, which is provided with aligned perforations which form an opening and can be closed again by a label. The label is disclosed as having on one side two adhesive areas separated by a non-adhesive area extending across substantially the entire width of the label. The two adhesive areas are adapted to adhere to the package on each side of the perforation line. A satisfactory method and apparatus for forming a seal and a single perforation to provide a tear strip to provide an initial indication of tampering is not disclosed.

[0006] Accordingly, systems are still being developed to form a reclosable tamper-evident seal that can be economically employed to safely protect the contents of a bag before being opened by the end consumer. It has not been. SUMMARY OF THE INVENTION The apparatus disclosed herein is used to form a tamper-resistant seal on a plastic bag. Here, both sides of the bag are welded together to form a seal adjacent to a row of perforations formed in the bag so that the seal can be torn from the bag. After the seal and perforated strip have been formed in the bag, the bag neck is narrowed and tied by twisting a wire-like ribbon around the bag neck.

The device for forming a tamper-resistant seal is preferably mounted on a bag tying device of the type disclosed, for example, in US Pat. No. 5,483,134, the entire disclosure of which is hereby incorporated by reference. Are cited here as forming. The gathering belt is attached to a pulley synchronized with the gathering belt of the bag tying device.

The bladder neck is flattened near the gathering belt, and the flattened bladder neck moves adjacent to rollers with projections forming perforations in the bladder neck.
The bag passes between a pair of manifolds that apply a stream of heated air to the upper and lower surfaces of the bag neck to seal the bag. The manifold does not contact the face of the bag so that the neck of the bag can be sealed even if the printing ink on the surface of the bag is not dry or if heat softens the printing ink.

Once the seals and perforations have been formed in the bag, the bag neck passes through a tying device, where the bag neck is pursed, tied, and tied in a conventional manner. Discharged from the device.

[0010] Instead of a twisted wire string around the pursed neck, a plastic wireless twisting string or other closing means, such as a plastic clip with slots or adhesive tape, is attached to the pursed neck of the bag. You may. This closure is
The bag is sealed between the perforations and the contents to prevent contamination and maintain the freshness of the contents of the bag. DESCRIPTION OF THE PREFERRED EMBODIMENT A wire binding device, generally designated 10 in FIGS. 1 and 2 of the drawings, is disclosed in U.S. Pat. No. 3,138,904 and U.S. Pat. No. 3,919,829. Provided adjacent to the side of a conveyor 300 of the type described above, the entire contents of such U.S. Patents are hereby incorporated by reference to form a part of this specification. The conveyor 300, for example, continuously loads the loaf of bread 125a, 125b, 125c into the wire tying device 10 and passes it through and out of it. The conveyor 300 is well known to those skilled in the art, and a detailed description thereof is not considered necessary except as described in connection with the drive mechanism, as described in detail below. It should be understood that the conveyor may be formed in other and other configurations.

[0011] The loaf of bread 125c is moving toward the bag tying device 10, and the bag neck is positioned adjacent to the device 100 for forming a tamper-resistant closure on the bag neck. . Bag 125b is moved by conveyor 300 and gathering belt to a position where a wire-like ribbon is wrapped around the pursed neck of the bag and twisted. The loaf of bread 125a has just exited the binding device through the binding device 10. Referring to FIGS. 9 and 10 of the drawings, the apparatus 100 has the sides 125x, 125y of the bag 125 welded together to form a tamper-resistant seal strip 130. A row of perforations 132 is formed in the neck of the bag 125 adjacent to the seal strip 130 so that the seal strip 130 can be removed from the bag and the contents of the bag can be removed.

[0012] The twisted wire ribbon 115 connects the bag with the perforated strip 132 and the bag 1.
Seal between contents of 25a.

As best shown in FIGS. 9 and 10 of the drawings, opposite sides 125 x, 125 y of the bag are welded together along seal strip 130 and are adjacent to seal strip 130. Thus, a row 132 of perforations is formed.
After the tamper-evident seals 130, 132 have been formed in the bag neck 125, any conventional removable closure, such as a twisted wire lace 115, of the bag to maintain freshness and prevent contamination of the bag contents. A slotted plastic clip or adhesive tape that grips the neck may be attached to the bag neck. Seal strip 13
A 0 can be easily removed by tearing the bag along the perforated rows 132.

A bag 125 that allows the seal strip 130 to be identified as tampered with
Obviously, the seal strip 130 must be removed by constructing the closure for a and tearing along the rows 132 of the bag perforations to access the contents of the bag. The bag can then be opened by removing the torsional strap 115, and the bag can be resealed by reattachment.

The device 100 for forming a tamper-resistant closure includes a pair of rollers that engage opposite sides of the bag neck to form a perforated row 132 and a heated gas, such as air, to the perforated row 132. The bag neck panels have a pair of manifolds for welding the panels of the bag neck together to form a sealing strip 130, with the panels facing the surface of the neck of the adjacent bag.

Referring to FIGS. 3, 4 and 8 of the drawings, reference numeral 140p generally designates a roller having teeth 142p provided therearound, wherein a roller 150p has a groove for receiving the teeth 142p of the roller 140p. 152p is formed. Roller 1 bag
Moving between 40p and roller 150p, teeth 142p of roller 140p
A hole is drilled in the neck of the bag to form a row of perforations 132 in the neck of the bag.

As best shown in FIGS. 2 and 8 of the drawings, a pair of gathering belts 41, 43 hang around driven rollers 140, 144 and a drive roller 145 attached to a shaft 146. ing. At the opposite end of the shaft 146 is mounted a pulley 147, which is driven by a belt 25a wrapped around pulleys 147,148. The pulley 148 is connected to the shaft 2
5, the shaft 25 is connected to the driven pulley 24 of the bag tying device 10.
And drives the upper gathering belt 22 wrapped around the idler pulleys 26, 27, 28.

A groove 152p is formed on the surface of the roller 150p.
Are driven by a pair of gathering belts 51 and 53 wound around rollers 150, 154 and 155, as shown in FIG. The drive roller 155 is
6, and a pulley 157 is attached to an end of the shaft 156. A drive belt 35a is hung around a pulley 158 attached to the end of the shaft 35, and the shaft 35 is tied around the driven pulley 34 and the pulleys 36, 37, 38 of the bag tying device 10. The lower gathering belt 32 is driven.

It should be noted that the upper gathering belts 41, 43 and the lower gathering belts 51, 53 grip the bag neck adjacent both sides of the bag segment to be sealed to form the sealing strip 130. is there. Tooth 142 of roller 140p
p is preferably spaced from the gathering belt adjacent to the bag neck segment between 41,43.

The roller 140p on which the teeth are formed is driven in synchronization with the gathering belt 22 by a belt 25a hanging around the pulleys 147 and 148, and the roller 150p on which the groove 152p is formed is a pulley. Obviously, the belt 35a hung around 157 and 158 drives in synchronism with the lower gathering belt.

The rollers 140, 144, 145 are mounted on a mounting plate 149, and the rollers 150, 154, 155 are mounted on a mounting plate 159.
Both ends of the shafts 146, 156 are supported by mounting plates 149a, 159a.

The top plate 149b has opposite ends secured between the mounting plates 149, 149a by screws, and the side plate 149c is mounted generally perpendicular to the top plate 149b. , 149a extending vertically.

An upper heater 160 is secured to the top plate 149b by U-bolts 162, 164, as best shown in FIGS. 6 and 7 of the drawings. A rear end of the upper heater 160 is connected to a passage 160a formed in the mounting plate 149a.
Extends through it.

A lower heater 170 extends through an opening formed in the mounting plate 159, 159a, and the heater is mounted in a bottom mount adjacent a vertically extending mounting plate 159c by U-shaped bolts 172,174. It is fixed to the plate 159b.

The heated air is sent from the heater 160 into the upper manifold 165 and the heated air is sent from the heater 170 into the lower manifold 175.

The manifolds 165, 175 are preferably formed with elongated orifices that form a row of air jets, the air jets comprising the manifolds 165, 175.
5 Discharged to strike the surface of the neck of the bag moving between each other. The temperature and air volume of the air are selected to deliver sufficient heat to fuse the panels of the bag together to form the sealing strip 130.

By releasing a jet of heated air and applying it to the surface of the bag, the panels of the bag can be sealed without the heated sealing elements sealing the physically contacted surfaces of the bag. It should be understood that welding is possible. Thus, the sealing strip 130 can be formed on the neck of the bag, even with uncured wet ink or ink softened by heat. The wet or softened ink does not transfer to the manifolds 165,175. This is because the manifold does not physically contact the surface of the bag neck.

The air manifolds 165, 175 preferably have twenty orifices, for example, about 0.040 inches (about 1.016 mm) arranged to form an outlet opening, such outlet openings comprising: The air flow is released to allow the panel 12 above and below the neck 125 of the bag.
5x, 125y, and heat panels 125x, 125y to a temperature sufficient to fuse panels 125x, 125y together to form sealing strip 130.

[0029] The heaters 160, 170 preferably electrically heat the air flowing therethrough, and this air is supplied to an air supply line 180, as shown in Figure 2 of the drawings.
From the pressure regulator 182, the filter 184 and the supply line 185. Air supply line 185 is preferably connected to heater 160 through line 187.
, 170 are passed through a control valve 186 for controlling the pressure and the amount of air sent to the air. The heater mount of the lower heater 170 has a substantially mirror image relationship with the heater mount of the upper heater 160, and the heaters 160 and 170 are separated from the rollers 140 and 150 by a piece attached to a loaf of bread in the bag 125. The rollers 140 and 150 are attached to a frame so that the rollers 140 and 150 can be separated from each other when dropped into the nip. The roller 140 is spring-pressed downward toward the roller 150,
It can be pivoted upward if necessary, so that shards or other obstacles
, 150 through the nip.

Each heater 160, 170 preferably includes an electrical heating element, which includes a thermostat suitable for regulating the temperature of the air sent from heaters 160, 170 to manifolds 165, 175. Connected through. further,
Thermocouples are provided in manifolds 165 and 175 to indicate the temperature of the air supplied by heaters 160 and 170 and to maintain this temperature within a predetermined range.

As shown in the table of FIG. 11, the temperature of the air required to form the sealing strip 130 depends on the thickness and composition of the materials used to form the bag 125 and the manifold 165 of the bag neck. , 175 depending on the speed of the conveyor 300 moving between them. As the bag thickness increases, the temperature of the air sent through the air manifolds 165, 175 generally increases. As the speed of the conveyor increases, the temperature of the air rises and a controlled air flow and heat to form the sealing strip 130 is sent through the manifolds 165,175.

The pressure of the air supplied through the pressure regulator 182 is preferably about 25 psi
And the heaters 160, 170 are preferably selected to heat the air flowing through the manifolds 165, 175 to a maximum temperature of, for example, 600 ° F. (approximately 315.6 ° C.). The thermocouple provides a reading of the temperature of the air flowing through the manifolds 165, 175, and the temperature of the air sent through the heaters 160, 170 generates the desired amount of heat to form the sealing strip 130. Can be adjusted.

The wire binding device, generally indicated at 10 in FIGS. 1 and 2 of the drawings, is itself claimed in the claims, except when combined with a device for forming a tamper-resistant closure. Do not make the main part of. The wire tying device has, as main components, upper and lower gathering belts 22, 32 as shown in US Pat. No. 5,483,134, and the upper gathering belt 22 is driven by a pulley provided on a shaft 25. The lower gathering belt 32 is driven by a pulley provided on a shaft 35. As described above, the operation of the rollers in the device for forming the tamper-resistant closure is synchronized with the rotation of the shafts 25, 35 via the belts 25a, 35a.

The upper and lower gathering belts 22, 32 hold the bag 125 around the needle assembly, the hook assembly of the twisting device, and the wire strap around the pursed neck of the bag 120. Moving along a path leading to a location near a shear assembly (not shown).

For example, the terms “horizontal”, “vertical”, “up” and “down” when used in connection with the drawings generally indicate the orientation of the components in the illustrated embodiment, The orientation need not be exactly as described.

Second Embodiment A second embodiment of an apparatus for forming a tamper-resistant closure on the neck of a bag comprises:
This is shown in FIGS. The components of this device are substantially the same as in the first embodiment, except that some components and operation modes are exchanged.

Referring to FIGS. 16 and 18, a heater housing 200 is provided between the end walls to form a partition wall for forming a high temperature region 201, an intermediate region 203 and a low temperature region 205 in the heater housing 200. 202 and 204. An air filter is provided in the intermediate region 203 for cleaning air that is provided in the low temperature region 205 and drawn into the intermediate region by the blower 230 for sending air to the heaters 260 and 270. As described in detail below, an exhaust fan 208 for exhausting used air from the heater housing 200 is provided in the high temperature region 201.

Referring to FIGS. 12 and 18 of the drawings, an external upper gathering belt 241 and an internal upper gathering belt 243 are attached to an upper chassis 222,
The lower gathering belt 251 outside the machine and the lower gathering belt 253 inside the machine are
It is attached to the lower chassis 225.

The lower chassis 225 supporting the belts 251, 253 may indicate that the capacitive sensor 215 (best shown in FIG. 14) has a snip or other obstruction falling into the bag neck. Can be moved from the position shown in FIG. 12 to the position shown in FIG. After removing the shards or other obstructions, resetting the system returns the lower chassis 225 to the position shown in FIG.

The outer upper gathering belt 241 includes an outer timing belt pulley 240,
Hangs around 244, 245, 246. In-machine upper gathering belt 2
43 hangs around the pulleys 240a, 244a, 245a, 246a. Pulleys 240 and 240a are attached to shaft 240b and pulley 244
, 244a are attached to the shaft 244b, and the pulleys 245, 245a are
Attached to shaft 245b, pulleys 246, 246a
b.

As best shown in FIG. 18, upper chassis 222 includes spaced apart plates 221, bolted or otherwise secured between end walls.
223. In the illustrated embodiment, the upper chassis cannot move, and the shafts 240b-246b are spaced apart from each other by the spaced plates 221.
, 223 are supported by bearings 227 provided in the inside.

The outer lower gathering belt 251 is provided with outer pulleys 250, 254, 255,
Hanging around 256. The lower gathering belt 253 in the machine is connected to the pulley 2
It hangs around 50a, 254a, 255a, 256a. Pulley 250,
250a is attached to shaft 250b, pulleys 254, 254a are attached to shaft 254b, and pulleys 255, 255a are attached to shaft 255b.
, And the pulleys 256 and 256a are attached to a shaft 256b. The lower chassis 225 is formed by spaced plates 224, 226 that are bolted or otherwise secured between slides or slide plates that move perpendicular to the end walls. In the illustrated embodiment, the lower chassis is movable and the shafts 250b-256b are supported by bearings 228 provided in spaced apart plates 224,226. As described in detail below, the bearings 227 and 228
Inward from 256b and manifolds 265, 275, a sufficient distance to prevent excessive heating of bearings 227, 228 by used air vertically drawn into hot zone 201 in heater housing 200 by exhaust fan 208. Is located.

The piercing wheel 220 is driven by a belt 240x hanging around a hub provided on the piercing wheel 220 and by a pulley (not shown) provided on the shaft 255b.

An air nozzle 209 shown in FIG. 14 is connected to a flexible tube 209 a through which air is pumped out of an air compressor (not shown) or other suitable source of compressed air for jetting. The jet flattens the bladder neck and urges it into a first pair of brushes 210, 214 positioned above the edges of the conveyor and a second pair of brushes 210, 214 positioned below the edges of the conveyor. It is positioned to enter the nip between the two pairs of brushes 212,216. The air jet applies the side 125x of the bag 125a to the bag 1
25a to the side 125y.

A volume sensor 2 for detecting when a piece of bread loaf falls into the neck of a bag
15 are positioned between the air nozzle 209 and the brushes 210-216. If a snip or other obstruction falls into the neck of the bag, the sensor will signal to stop the conveyor and activate the sealing device to the inoperative position as shown in FIGS. The sensor 215 is a capacitor-type sensor that detects a change in mass outside a predetermined range adjacent to the sensor.

If there are no obstacles in the bag neck, the bag neck moves between the upper and lower pairs of brushes. The first upper brush 210 and the lower brush 212 best shown in FIG. 14 have bristles and rotate in opposite directions, so that the lower surface of the upper brush 210 and the upper surface of the lower brush 212 It moves in the same direction and engages the neck of the bag, thereby pulling the bag laterally of the conveyor, eventually causing the contents of the bag to engage the guide bars, which guide the contents of the bag. Moves and engages the guide bar to stop lateral movement of the bag. First upper and lower brushes 210,
The brushing action of 212 pulls the bag pin around its contents.

[0047] The second upper and lower brushes 214, 216 have spaced rows of diagonal bristles, the diagonal bristles moving the leading edge of the bag neck away from the trailing edge. Is slightly longer than the bristles of the first upper and lower brushes 210, 212 to flatten the neck and evacuate air from the bag before sealing the bag. The diagonally arranged bristles are preferably about 1/8 the diameter of the bristles of the first upper and lower brushes 210,212.
Inches (3.175 mm) longer.

A first pair of upper and lower brushes 210, 212 pulls the bag around the product, while a second pair of upper and lower brushes 214, 216 flattens the bag neck. It is evident that the air is evacuated from the bag and the leading edge of the bag neck is positioned between the upper belts 241, 243 and the lower belts 251, 253. A first set of brushes 210, 212 for moving the bag neck laterally of the conveyor resiliently hold the bag neck and a second pair of upper and lower brushes 214, 216 and a gathering belt. Tend to resist movement of the bag neck in the length of the conveyor obtained by the method. Thus, the leading edge of the bag neck is gripped by the gathering belt, and the trailing edge is pulled from between the brushes to allow the bag to divide the space between the gathering belt and the horizontally spaced belts 241, 243. The neck of the bag is stretched while straddling and being pulled between the neck portion of the substantially flat bag.

As shown in FIGS. 14 and 15, the piercing assembly is located below the neck of the bag and has a piercing wheel 220 circumferentially spaced with teeth 221 therearound, and And an anvil 218 provided with a slot 217. The neck of the bag is held between the lower surfaces of the belts 241 and 243 and the upper surfaces of the belts 251 and 253 in a state of being pulled with pins.

Each tooth 221 of the piercing wheel 220 is shaped to provide a predetermined cut or elongated slot in the neck portion of the bag straddling between the belts. A region 221a of predetermined length is formed between adjacent teeth 221 of the drilling wheel 220 so as to leave uncut, spaced regions at the neck of the bag. A piercing wheel 220 is driven by a pair of belts in synchronism with the belt moving the bag so that any bags moving adjacent to the piercing wheel are substantially identical.

The piercing wheel 220 is attached to a short shaft fixed to the lower belt chassis 225 via a bearing. The piercing wheel teeth extend into slots in the lower surface of the anvil supported by the upper chassis 222 such that the bladder is supported by flat surfaces adjacent the opposite sides of the piercing wheel.

Referring to FIG. 12 of the drawings, as described above, the upper gathering belt 241
, 243 are attached to the upper chassis 222 and the lower gathering belt 251
, 253 are attached to the lower chassis 225. The lower chassis 225 supporting the belts 251 and 253 can move from the position shown in FIG. 12 to the position shown in FIG. 13 if the capacity sensor 215 detects a piece dropped into the neck of the bag. After removing the shards or other obstructions, resetting the system returns the lower chassis 225 to the position shown in FIG. Drilling wheel 225 is driven by a belt 240x, which is hung around a hub provided on the drilling wheel and driven by a pulley (not shown) mounted on shaft 255b.

Referring to FIGS. 18 and 19 of the drawings, a shaft 240b with pulleys 240 and 245a and a shaft 255b with pulleys 255 and 255a were hung around the pulleys as shown in FIG. 19 of the drawings. Driven by the belt 320. The shaft 245b is an idler shaft, and has no pulley at its rear end.

A pulley 304 for driving the timing belt pulleys 254 and 254a is attached to the shaft 255b. Timing belt pulley 350, 350
A pulley 305 for driving a is mounted on the shaft 256b. The idler pulley 306 is attached to a short shaft supported by the lower chassis 225.

A DC drive motor 315 for driving the belts 241, 243, 251, 253 at a speed equal to the surface speed of the conveyor 300 may be provided by suitable driving means, such as an output from a binding device or a decoder module provided on the conveyor. Is electrically connected to The motor 315 has a drive pulley 310 attached to a drive shaft for driving a belt 320, and the belt 320 is connected to the idler pulley 3.
09, a pulley 302 for driving the upper belts 341 and 343, a driving pulley 304,
Idler pulley 305, drive pulley 3 for driving shafts 246b, 256b
06 and around the pulley 308.

The upper chassis 222 supporting the upper belts 241 and 243 does not move. The lower chassis 225 supporting the belts 251, 253 can be moved vertically, as shown in FIG. 19, thus lowering the lower chassis 225 to separate the upper and lower pairs of belts from each other. Can be moved to a position. Referring to FIG. 19, it is clear that the length of the drive belt 320 does not change when the chassis 225 moves downward. This is because, when the chassis 225 moves vertically, the pulleys 304, 305, 306 rotate and advance along the belt 320. Thus, the belt tension does not change.

Referring to FIG. 16 of the drawings, a three-stage blower 230 sends a large amount of pressurized air to electric heaters 260 and 270. The heaters 260, 270 are preferably configured to circulate air over the heating element, which heats the air to a controlled temperature and directs the air via diverter valves 262, 272, respectively. An upper manifold 265 and a lower manifold 275 are provided. Each of the manifolds 265 and 275 has an elongated slot through which heated air is sent out and the outer belts 241 and 251 and the inner belt 24 are formed.
3,253 to the flattened surface of the neck of the bag straddling the space. It should be understood that perforation rows 132 have already been formed in the bag neck by the piercing wheel 220 before the bag neck is moved between the upper manifold 265 and the lower manifold 275. This allows the bag to be pierced while cooling, which is performed before the bag is heated to a temperature that tends to stretch and deform when the teeth 221 of the piercing wheel 220 engage the neck of the bag. Will be The heated air flowing at high speed hits the upper and lower surfaces of the neck of the bag, and the upper and lower surfaces are welded to each other. It is understood that air impinges on the portion of the bag that straddles between the belts, and that the molten plastic or the ink softened by the hot air does not transfer to the belt or any other mechanism prior to cooling the bag neck. Should be.

The upper diverter valve 262 and the lower diverter valve 272 include spring-loaded paddles that are rotated by the air cylinder from the position shown in FIG. 16 to the position shown in FIG. 17 when the lower chassis 225 is operated to the inoperative position. ing. This causes the heated air to diverge away from the bladder neck, which may be located adjacent to the manifolds 265, 275, through the exhaust port when the lower chassis 225 is moved downward. By diverting the air as shown in FIG. 17, the air is also directed away from the vicinity of the belt, thereby preventing the belt from overheating.

As best shown in FIG. 16, the three-stage blower 230 includes a partition wall 204.
And air is passed through the air filter 206 to the intermediate region 203.
It has an intake line 230a for drawing in from the inside. Air is blown by the blower 232 through the lines 260a, 270a to the heaters 260, 270. The air preferably flows from the heaters 260, 270 along the plurality of paths to the diverter valve 26.
2,272. When the spring-loaded paddle is in the position shown in FIG. 16, air is channeled through the manifolds 265, 275 and strikes the upper and lower surfaces of the outboard belt and the bag neck straddling the outboard belt. When the levers 262a and 272a are turned, the spring-pressed paddle moves from the position shown in FIG. 16 to the position shown in FIG. 17 and sends air through the exhaust ports 262e and 272e to the high-temperature region 201. Air is exhausted from the high temperature area 201 by exhaust fans 208 provided at the upper end and the lower end of the area 201.

The diverter valves 262, 272 located in close proximity to the manifolds 265, 275
This allows the air to be diverted and quickly returned from the manifold to the exhaust port and back to the manifold. Because the heated air is flowing continuously through the diverter valves 265, 275, the mechanism described above ensures that the temperature does not deviate from an acceptable level and that the paddle is moved from one position to another. Does not require a warm-up period.

Since the intermediate region 203 is provided between the high temperature region 201 and the low temperature region 205, the high temperature region 201 is effectively isolated from the low temperature region 205 where the electric control device and the blower 230 are provided. Further, the filter 2 adjacent to the partition wall 202
By drawing air into 06, the air drawn into blower 230 is preheated.

The three-stage blower 230 supplies a large amount of relatively high-pressure air to the heater and the manifold 2.
65, 275. Heating air on the heating element 26
By continuously and stably feeding through 0,270, the temperature and air volume of the air are
Maintained within parameters to seal the bag neck as it passes between manifolds 265 and 275 while preventing excessive heat from being delivered. Heater 26
The heating element in the 0,270 is controlled by the action of a thermostat to adapt to bags made of various materials or of different thicknesses of plastic.

It is important to note that the brushes 210, 212, 214, 216 flatten the neck of the bag, evacuate excess air from the inside of the bag, and remove the perforated rows 132 and the sealing strips 130. It is configured so that it can be formed consistently around the neck of the bag.

The belt is preferably a timing belt having undercut or shortened teeth 241t such that the edge of the belt can extend beyond the flange of the timing belt pulleys 240-256a supporting the belt. As a result, the neck of the bag is not wound around the flanges of the belt and the timing belt pulley, and is not caught between them. Vulcanizing a layer of soft and flexible material 241x on the outer surface of each belt body 241y provides a relatively hard and durable surface for engaging the timing belt pulley and a sewn neck around the bag. A relatively soft and flexible surface to engage is obtained on each belt. This causes the belt to grab the bag and place the neck of the bag adjacent to the piercing wheel 220 and the neck of the bag is formed with the upper and lower manifolds 265 and 275 where the sealing strip 130 is formed.
Minimize slippage when moving between.

A Teflon reinforced slider plate 300 s is fixed to a mounting plate 301 that is bolted or otherwise fixed to the upper chassis 222 and the lower chassis 225. The belt spanning the space between the pulleys 344, 345 and between the pulleys 354, 355 engages the slide plate 300x, thereby preventing the belt from flexing, thereby causing the belt to move to the upper manifold 265 and the lower manifold 275.
To grip the spaced apart portions of the bag neck adjacent to the opposite sides of the bag.

As best shown in FIG. 12 of the drawings, levers 262 a, 272 a extend outwardly from the diversion valves 262, 272, which are provided on the cylinder rods and The spring push paddle in the valve is moved from the position shown in FIG. 16 to FIG.
Engage with the turnbuckle to move to the position shown.

Although a preferred embodiment of a method and apparatus for forming a tamper-resistant seal has been disclosed, it is clear that other embodiments can be envisaged without departing from the basic concept of the invention.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS The drawings of a preferred embodiment of the present invention are attached hereto so that the invention may be more fully understood.

FIG. 1 is a perspective view showing the front of a neck tying device for a bag provided with a device for forming a tamper-evident seal.

FIG. 2 is a rear view of a bag tying device and a device for forming a tamper-resistant seal.

FIG. 3 is a partially enlarged perspective view showing a gathering belt at the neck of the bag and a toothed roller for forming perforations.

FIG. 4 is a partially enlarged view showing a roller for punching a bag.

FIG. 5 is a perspective view showing a back surface and a side surface of an apparatus for forming a tamper-proof seal.

FIG. 6 is a perspective view of an apparatus for forming a tamper-resistant seal, with the cover removed to clearly show details of its construction.

FIG. 7 is an enlarged view showing a relationship among a heater, an air manifold, and a punching roller for forming a tamper-proof seal.

FIG. 8 is an exploded perspective view showing parts of an apparatus for forming a tamper-proof seal.

FIG. 9 is a partial schematic view showing a perforated line formed on the neck of the sealed strip and bag.

FIG. 10 is a perspective view of a bag showing a relationship between a seal strip, a perforated line, and a removable stopper.

FIG. 11 is a table showing an example of the relationship among conveyor speed, bag thickness, and temperature.

FIG. 12 is a perspective view of the belt assembly in an operative position.

FIG. 13 is a view similar to FIG. 12, with the lower belt cradle in a lower position;

FIG. 14 is a schematic view with the belt in the position shown in FIG.

FIG. 15 is a schematic view with the belt assembly in the position shown in FIG.

FIG. 16 is a schematic diagram of a heater and manifold assembly, wherein the belt assembly is shown in FIGS.
In the position.

FIG. 17 is a schematic view similar to FIG. 16, with the belt assembly in the position of FIGS. 13 and 15;

FIG. 18 is a schematic side view.

FIG. 19 is a schematic view substantially along the line 19-19 of FIG. 18; The reference numbers are used to indicate the same elements in the figures.

──────────────────────────────────────────────────続 き Continuation of front page (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE ), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SL, SZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY , CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GE, GH, HU, IL, IS, JP, KE, KG, KP, KR, KZ , LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, TJ, TM, TR, TT, UA, UG, US, UZ, VNF term (reference) 3E049 AA06 BA04 CA04 DB01 EA02 EB02 FA04 FA07 3E094 AA12 BA12 CA19 CA33 CA37 DA08 FA12 FA19 FA26 GA11 HA01 HA08

Claims (11)

[Claims] 1. A method of forming a tamper-resistant seal on a plastic bag containing a loaf of bread, comprising: flattening a portion of the bag neck adjacent an open end of the bag; Securing at least a portion of the flattened portion so that the product therein cannot be accessed; shrinking the flattened portion of the bag between the sealing portion and the product; Attaching a reusable closure. 2. The method of claim 1, further comprising the step of piercing said bag between said secured portion and said product to form a perforated strip. 3. The step of securing at least a portion of the flattened portion of the bag neck includes the step of applying a heated stream of air to the surface of the bag to weld the panels of the bag together. 2. The method of claim 1, comprising moving the neck of the bag to form a sealed strip. 4. The step of securing at least a portion of the flattened portion of the bag neck has been heated to a temperature of about 315 ° -600 ° F. (about 157.2-315.6 ° C.). The method of claim 1, comprising flowing air to a surface of the bag and gripping portions of the bag adjacent both sides of the portion of the bag to which the air stream is directed. 5. A method of forming a tamper-evident closure in a plastic bag containing a product, the method comprising: forming a row of perforations in the bag; and positioning the bag in a spaced position adjacent to the row of perforations. And directing temperature-controlled air between the gripped portions of the bag to form a sealed strip adjacent the perforated row. 6. An apparatus for forming a tamper-resistant closure in a plastic bag containing a product, the means for gripping a spaced apart portion of the bag, and adjacent to the gripped portion of the bag. Means for forming perforation rows in the bag; and the bag between the gripped portions to weld portions of the bag between the gripped portions to form a sealed strip. Means for delivering temperature-controlled air to impinge on the surface of the device, wherein the perforations are arranged such that the sealed strip can be removed. 7. The means for gripping the spaced portion of the bag comprises a pair of horizontally spaced upper belts and a pair of horizontally spaced lower belts, wherein The upper belt and the lower belt are arranged so as to be engaged with a separated position of the bag neck so that the bag neck straddles the space between the upper belt and the lower belt. 6. An apparatus for forming a tamper-resistant closure in a plastic bag. 8. The means for forming perforations in said bag adjacent said gripped portion comprises: an anvil with a slot formed adjacent one side of a neck of said bag. A piercing wheel with cutting teeth disposed adjacent the other side of the bag neck, wherein when the bag neck moves between the anvil and the piercing wheel, the cutting teeth 7. The apparatus for forming a tamper-resistant closure in a plastic bag of claim 6, wherein the device pierces a bag and penetrates a slot formed in the anvil. 9. A means for sending temperature-controlled air to impinge on the surface of the bag, an upper manifold located above the neck of the bag, and a lower manifold located below the neck of the bag. A side manifold; and means for delivering air through the upper and lower manifolds to abut the neck of the bag, wherein the air comprises a sealed strip extending substantially parallel to the row of perforations. The apparatus for forming a tamper-resistant closure in a plastic bag of claim 6, wherein the device is heated to a temperature sufficient to melt the neck of the bag for forming. 10. A diverter valve adjacent each of the upper manifold and the lower manifold, the diverter valve configured to interrupt the flow of air to the diverter valve without interruption of air flow to the upper manifold and the lower manifold. Drivable to deflect airflow from the manifold and exhaust air,
Apparatus for forming a tamper-resistant closure in the plastic bag of claim 9. 11. Apparatus for forming a tamper-resistant closure in a plastic bag containing a product, the plastic bag containing an open end forming a neck that extends beyond the product in the bag. A conveyor for moving the bag along the path, an air nozzle for flattening the open neck when the bag is moved by the conveyor, and a pair of upper brushes and a pair of lower brushes, A first of the pair of upper and lower brushes engages the flattened neck of the bag to pull the bag laterally across the conveyor, and a second upper and lower upper brush. A brush with the trailing edge of the bag neck engaging the first upper and lower brushes;
The apparatus further includes an inclined brush for moving a leading edge of the bag in a longitudinal direction of the conveyor, the apparatus also includes one upper belt and a pair of lower belts, one of the upper belt and one of the upper belts. The lower belt engages both sides of a portion of the neck of the bag, and one of the upper belts and one of the lower belts has a portion of the neck of the bag which is the upper pair of belts and the lower belt. The upper and lower belts are horizontally spaced from each other to engage a second portion of the bag neck to span the space between the pair of belts; Also has a piercing wheel adjacent one side of the bag neck and an anvil with a slot formed adjacent the other side of the bag neck, wherein the piercing wheel is Neck of the bag moved by upper and lower belt Forming a row of perforations, the apparatus also sends heated air, applies heated air to the upper and lower surfaces of a portion of the neck of the bag straddling between the belts, melts the air, and forms the neck of the bag. Device having upper and lower air dispensers for forming a sealed strip over the full width of the bag neck so as to form a seal extending substantially parallel to the perforated rows.