US3835755A

US3835755A - Bag tie dispenser

Info

Publication number: US3835755A
Application number: US00343451A
Authority: US
Inventors: E Jones
Original assignee: Canadian Industries Ltd
Current assignee: NATIONAL TRUST Co A TRUST Co OF ONTARIO
Priority date: 1972-04-10
Filing date: 1973-03-21
Publication date: 1974-09-17
Anticipated expiration: 1991-09-17
Also published as: AU5331773A; CA990114A; GB1422779A; IT981909B; AU472468B2; DE2317189A1; FR2179853B1; FR2179853A1; JPS5722747B2; JPS4948496A

Abstract

An apparatus that cuts a strip of plastic film from a length of film advanced by a film metering device, applies a drop of adhesive to the strip and forces the adhesives bearing side of the strip into contact with the surface of a plastic bag, thus providing an attached bag tie. The apparatus is suitable for use at the output of a bag making machine, means being provided to attach the bag tie to a moving bag in correct register with the bag mouth.

Description

Elmfite @tates Patent 11 1 1111 3,835,755

Jones 1 Sept. 17, 1974 BAG TIE DISPENSER 3,099,237 7/1963 Currin et al. 93/35 os x 3,355,995 12/1967 Borkmann et al 93/1 TS [751 invent Elwyn Jones Bebe, 3,411,418 11/1968 Seragnoli 93/1 TS Quebec, Canada 3,579,397 5 1971 Schwarzkopf 93/1 TS ux A ig Canadian Industries Limited 3,773,591 ll/l973 Blalt 93/35 H X Montreal, Quebec Canada 3.794545 2/1974 Lucas 93/8 WA Filedl 1973 Primary ExaminerRoy Lake 2 APPL 343,451 Assistant Exam1'ner.lames F. Coan Attorney, Agent, or Firm-Alexander O. McIntosh [30] Foreign Application Priority Data ABSTRACT Apr. 10, 1972 Great Br1ta1n l640l/72 An apparatus that cuts a str1p of plast1c t1lm from a 52 us. 01 93/8 WA, 93/35 v13, 156/519, length of film advanced y 9 film metering device. 9- 5 /57 plies a drop of adhesive to the strip and forces the ad- 51 1m. (:1 B31b 1/90 hesives bearing side of the Strip into Contact with the [58] Fi ld f s h 93 3 W 3 R, 1 5 35 VL, surface of a plastic bag, thus providing an attached 93/35 D3 3 5 H; 15 519 573 bag tie. The apparatus is suitable for use at the output of a bag making machine, means being provided to at- [5 3 References Cited tach the bag tie to a moving bag in correct register UNITED STATES PATENTS the bag 9 2,995,174 8/1961 Wang 156/519 8 Claims, 3 Drawing Figures aaa'mss PAIENIED sen 71924 sum 1 ur 2 PAIENIEUSEPITIQYI 3335.155

SHEEI '2 [IF 2 MACH/NE I I 5 I 44 I I I I BAG TIE DISPENSER This invention relates to an apparatus for forming bag ties and for attaching said ties to a bag.

Bags are used extensively as containers for a variety of products. Frequently this use requires that the bag be closed by means of a tie. Such ties may be of wire enclosed within paper tape, or be strips of flexible sheet plastic. 1t is usual to include a group of ties with such bags when they are sold to the public, the ties being enclosed as separate articles with the package of bags. This is common practice with bags intended for domestic use as containers for food, and also with bags used to handle garbage.

There is a disadvantage is supplying bag ties separately with packages of bags, since the consumer may lose the set of ties before the bags in the package are exhausted. There is therefore an advantage in having a bag tie attached directly to the bag. However, such a method of providing bag ties will require extensive manual labour unless a machine method of attaching ties to bags is devised.

The present invention provides an apparatus that forms strips of flexible material and attaches such strips to bags with adhesive in position appropriate to serve as ties to close the bags.

Therefore, the primary object of this invention is to provide a means for the rapid attachment of bag ties to bags. An additional object is to provide a means for preparing bag ties from plastic sheet material. Further objects will appear hereinafter.

The apparatus of this invention comprises 1. means for providing a strip of flexible material,

2. means for applying a portion of adhesive to the surface of the strip,

3. means for placing the strip with the adhesive carrying surface in contact with the surface of a bag in position for service as a bag tie.

A preferred embodiment of the apparatus of this invention comprises 1. means for cutting a strip from a length of flexible material to form a bag tie, said cutting means being located adjacent to a bag supporting means,

2. adhesive applicator adapted to apply a portion of adhesive to the surface of the strip,

3. guide means adapted to guide the strip on to the surface of a bag supported by the supporting means, and

4. pressing means adapted to press the adhesive carrying surface of the strip against the bag on the supporting means.

Normally, the adhesive will be applied to the central part of the strip.

The invention is illustrated by way of example in the accompanying drawings wherein FIG. 1 is a view, partly diagrammatical, of the apparatus showing a cut strip of material passing between a strip cutting device and a roll carrying the bag to which it will be attached,

FIG. 2 is a side elevation of a strip cutting device, and

FIG. 3 is a schematic diagram of the electricalpneumatic control system of the apparatus.

Referring to the drawings at l is shown a roll over which is travelling a length of plastic bags 2 joined along transverse lines of perforations. Roll 1 can conveniently be an element of the bag folding and stacking machine disclosed in Canadian Pat. application No. 101,336 filed on Dec. 22, 1970 in the names of E. D. Jones and D. E. Scuffell (corresponding to British application No. 55494/71). At 3 is shown a strip of plastic film issuing from a strip cutting device shown generally at 4. The operations of roll 1 and strip cutting device 4 are synchronized so that strip 3 falls on the length of bags intermediate two transverse lines of perforations and adjacent to a bag mouth. At 5 is shown a gun adapted to eject a small portion of adhesive onto the under surface of strip 3. The operation of gun 5 is synchronized with the operation of cutting device 4 so that the adhesive will land on the central part of strip 3. When strip 3 falls on the bag passing over roll 1 movable roll 6 is moved into contact with the strip and bag, forcing the strip into close contact with the bag and making an adhesive bond between the two. Roll 6 is then withdrawn.

Strip cutting device 4 functions to cut strips of film from a length of plastic film. The length of film is shown at 7. A preselected length of film is metered by

rolls

8 and 9. Upper roll 8 is driven intermittently through the action of arm 10 connected to said roll through unidirectional clutch 11. The outer extremity of arm 10 is linked to the piston of air cylinder-piston unit 12 through clevis 13, so that the action of unit 12 drives roll 8. Roll 8 turns in bearings carried by

side plates

14 and 15.

To the opposite end of roll 8 is attached ratchet wheel 16. The rotation of 16 is controlled by cooperating pawl 17 pivotted on shaft 18. Pawl 17 is lifted out of engagement with ratchet wheel 16 by the action of the piston of air cylinder-piston unit 19. Pawl 17 is urged into e engagement with ratchet wheel 16 by means of a spring not shown. The function of ratchet wheel 16 and cooperating pawl 17 is to control reproducibly the amount of film metered by

rolls

8 and 9.

Lower roll 9 is mounted in bearings carried at the extremities of arms 20. Arms 20 are attached to cross shaft 21 which is joumalled in bearings in

side plates

14, 15. To the outer end of shaft 21 is attached arm 22. The free end of arm 22 is linked to the piston of air cylinder-piston unit 24 through clevis 23 attached to the piston. Through the action of 24 roll 9 is kept in engagement with roll 8 or it can be lowered so that film 7 may be threaded between the rolls.

The length of film is cut by the action of upper movable knife blade 25 and lower fixed knife blade 26. Knife blade 26 is carried by knife support 27 which is attached to

side plates

14, 15 of the apparatus. Knife blade 25 is carried by knife support 28 which is pivota bly mounted at 29 in knife support frame 30. Frame 30 slides vertically, being guided by four rollers 31 mounted in front plate 32, and two pinions 33. The two pinions are carried by cross shaft 34 and mesh with rack bars 35 mounted on frame 30.

The motion of knife frame support 30 and its knife blade 25 is effected by air cylinder-piston unit 36 which is mounted on top plate 37 of the apparatus. The piston of 36 is linked to clevis 38 carried by the upper cross piece of frame 30. Air cylinder-piston unit 39 is mounted on the lower cross piece of frame 30 with its piston linked to a projection of pivotted knife support 28. Air cylinder-piston unit 39'functions to press upper knife blade 25 agains lower knife blade 26 during the cutting of the film, thus facilitating the cutting action.

The strip of film cut by

knife blades

25 and 26 is guided onto the bag on roll 1 by means of lower guide 40 fixed to side plate 15, and upper guide 41 linked by hinge 42 to said side plate. Upper guide 41 is connected to knife suport 28 by link 43 which passes through a bore in said support. A helical spring carried by link 43 urges guide 41 downwards. Thus when knife blade 25 moves down, guides 40 and 41 grasp one end of the cut strip, causing the other end of the strip to hang down over roll 1.

The operation of the apparatus is coordinated by a pneumatic-electrical control system as illustrated in FIG. 3. Operation is initiated by a pulsed signal from the machine that processes the bags. This may be a bag folding and stacking machine. The timing of this pulse is synchronized with the operation of the machine delivering bags to the bag support roll 1 in order to ensure that the bag tie will be attached to the desired position on the bag, i.e., adjacent to the bag opening. When this signal is received knife blade 25 is in the lower position, having just cut off a strip of film which is held by guides 40 and 41. At this stage of the operating cycle movable roll 6 will be withdrawn from contact with roll 1. When the pulsed signal is received it actuates a first air valve V.l feeding air to air cylinder-

piston units

36 and 39, causing knife blade 25 to rise, releasing the cut strip 3 from guides 40 and 41. At the same time the control circuit actuates an air cylinder-piston unit 44 which causes movable roll 6 to press against roll 1, and adhesive gun is actuated by a pulse from pulse generator 47, ejecting a small amount of adhesive onto the under surface of the cut strip. The strip carrying the adhesive is then pressed against the bag on roll 1 by the action of roll 6.

When knife blade 25 rises cam operated microswitch 45 is actuated energizing the solenoid of air valve V2. Valve V2. then directs air to pulser 46, actuating air cylinder-piston unit 19 briefly to cause the momentary lifting of pawl 17 from ratched wheel 16. Air cylinderpiston unit 12 at the same time is actuated by air from V.2 lifting arm and causing the partial rotation of film metering roll 8. When the cam operating switch 45 passes this switch the switch opens causing the reversal of valve V.2. This causes the arm 10 of roll 8 to return to its original position, roll 8 remaining fixed in position due to the action of unidirectional clutch 1 1. The result of these operations is that film equivalent to the width of a bag tie has been advanced between open knife blades and 26.

When the initiating pulsed signal ceases the first air valve V.l is reversed, reversing the air supply to air cylinder-

piston units

36 and 39 causing knife blade 25 to cut off the strip of film that has been advanced between

knife blades

25 and 26. The cut off strip is then held by guides 40 and 41. The first air valve V.1 also feeds air to air cylinder-piston unit 44 controlling the position of movable roll 6, withdrawing this from contact with roll 1. The cycle can now be repeated upon reception of another initiating signal from the machine processing the bags.

Air valves V.1 and V.2 are both 4-way solenoid actuated, spring return valves.

Controls are provided so that first air valve V.l can be actuated manually, permitting manual operation of the apparatus. Also a manually operated air valve is provided to control air cylinder-piston unit 24 which controls the position of lower roll 9. The apparatus will also be provided with a safety guard which is adapted to disable the supply of air operating knife blade 25. Air of p.s.i.g. pressure is suitable for the operation of the apparatus.

What we claim is: 1. An Apparatus for forming bag ties and attaching said ties to a bag comprising 1. cooperating upper and lower knife blades adapted to cut a strip from a length of flexible material to form a bag tie,

2. bag supporting means located adjacent to the knife blades,

3. adhesive applicator adapted to apply a portion of adhesive to the surface of the strip,

4. guide means adapted to grasp the strip when the upper and lower knife blades are in cutting contact and to guide the cut strip on to the surface of a bag supported by the bag supporting means, and

5. rotatable roll adapted to be urged toward the bag supporting means thereby to press the adhesive carrying surface of the strip against the bag supported by the bag supporting means.

2. An apparatus as claimed in claim 1 wherein the upper knife blade is movable in a vertical sense and is adapted to be actuated by an air cylinder-piston unit.

3. An apparatus as claimed in claim 1 wherein there are provided cooperating upper and lower metering rolls adapted to advance a predetermined length of flexible material between the upper and lower knife blades in a position to be cut thereby to form a bag tie.

4. An apparatus as claimed in claim 3 wherein there is provided a switching means adapted to actuate the metering rolls when the upper and lower knife blades are separated.

5. An apparatus as claimed in claim 1 wherein the bag supporting means is a roll supported for rotation.

6. An apparatus as claimed in claim 1 wherein the ro tatable roll is adapted to be urged toward the bag supporting means through the action of an air cylinderpiston unit.

7. An apparatus as claimed in claim 1 wherein means are provided to actuate the rotatable roll in synchronisation with the operation of a machine delivering bags to the supporting means so that the bag tie is attached to the bag at a predetermined position.

8. An apparatus as claimed in claim 1 wherein the operation of the apparatus is coordinated by an electricalpneumatic control system.

Claims

1. An Apparatus for forming bag ties and attaching said ties to a bag comprising 1. cooperating upper and lower knife blades adapted to cut a strip from a length of flexible material to form a bag tie, 2. bag supporting means located adjacent to the knife blades, 3. adhesive applicator adapted to apply a portion of adhesive to the surface oF the strip, 4. guide means adapted to grasp the strip when the upper and lower knife blades are in cutting contact and to guide the cut strip on to the surface of a bag supported by the bag supporting means, and 5. rotatable roll adapted to be urged toward the bag supporting means thereby to press the adhesive carrying surface of the strip against the bag supported by the bag supporting means.

2. bag supporting means located adjacent to the knife blades,

6. An apparatus as claimed in claim 1 wherein the rotatable roll is adapted to be urged toward the bag supporting means through the action of an air cylinder-piston unit.

8. An apparatus as claimed in claim 1 wherein the operation of the apparatus is coordinated by an electrical-pneumatic control system.