GB2228729A

GB2228729A - Capping device

Info

Publication number: GB2228729A
Application number: GB9001618A
Authority: GB
Inventors: Kenneth Henry Hawkins; Clive Edric Glover
Original assignee: Boots Co PLC
Current assignee: Boots Co PLC
Priority date: 1989-01-24
Filing date: 1990-01-24
Publication date: 1990-09-05
Anticipated expiration: 2010-01-24
Also published as: GB9001618D0; GB8901460D0; GB2228729B

Abstract

Apparatus for positioning caps 34 on containers 28 comprises a passageway with an entrance 14 above an outlet end portion 16 and including a wall 18 having an opening (22, Fig. 1), preferably bounded at each side by lips 24, to support the cap 34 over the opening (22). Receiving portions of containers traveling in a feed direction B pass through the opening (22) and each engage a cap 34 held by a retaining member 30 at the outlet end portion. As a container continues in the feed direction B in engagement with the cap 34 the cap is withdrawn from the passageway, the retaining member 30 moving away from its rest condition allowing the cap to escape. Adjusting means 60 may if necessary adjust the final position of the cap. <IMAGE>

Description

CAPPING DEVICE This invention is concerned with a capping device and especially to apparatus suitable for use in positioning caps over openings of containers, for example in positioning caps on receiving portions of containers defining the opening, eg. necks of plastic containers, bottles, or the like.

In packaging products in plastics containers, bottles or the like having neck portions through which the contents to be packaged are introduced into the container and which subsequently must be closed by a closure member for example a cap, it is necessary to provide a means for applying a closure member or cap to the receiving portion of the container, namely the neck.

Various different shapes of container may be utilised and desirably the containers should be filled and capped as rapidly as possible. In order to deal with containers of a variety of different shapes, it has been necessary to build capping equipment especially adapted for each shape of container the capping equipment being adapted to hold the container in position for application of the cap. One known technique of applying caps to bottles and the like is known as pressure capping in which a cap positioned loosely in the correct position on the neck of the container is carried between two belt conveyors travelling at the same speed, the spacing between the two belts gradually diminishing so that progressively increasing pressure is applied to the cap: ultimately the cap snap fits over a co-operating engaging means on the neck portion of the container.This type of cap engaging system is especially attractive in that the system is operative in a continuous production line not in a stepwise manner as is the case with many other types of capping machines. However in order to utilise this pressure capping system it is essential that the cap be applied to the neck portion of the container in correct orientation before attempting to apply the pressure between the converging conveyor belts.

One of the various objects of the present invention is to provide improved apparatus for placing caps in correct position on a receiving portion of a container.

In one aspect the invention may be considered to provide apparatus suitable for use in positioning caps over an opening of a container propelled in a feed direction in the operation of the apparatus comprising dispensing means defining a passageway having an entrance portion into which caps may be introduced and an outlet end portion disposed below the entrance portion and positioned in a path along which a receiving portion defining said opening of the container is constrained to travel as a container moves in a feed direction, a wall of the outlet portion having an opening through which the receiving portion is constrained to pass as it travels along said path, the dispensing means further comprising retaining means positioned at the outlet end portion of the passageway to retain a cap at the outlet end portion of the passageway positioned over said opening for engagement with the receiving portion of a container travelling along said path, the retaining means being mounted for movement as the receiving portion engaged with the cap travels along said path to allow the cap to escape from the passageway.

In another aspect the invention may be considered to provide apparatus suitable for use in positioning caps on receiving portions of containers over an opening defined by the receiving portion, comprising a slideway of width slightly greater than the caps to be positioned having a wall portion for supporting a cap, an entrance portion at which caps can be introduced into the slideway and an outlet end portion at a lower end portion of the slideway, said wall of the slidway having an opening at said outlet end portion bounded at either side by lip portions adapted to support peripheral portions of the cap with the cap positioned over said opening in the wall of a slideway for engagement with the receiving portion of a container travelling in a feed direction through the apparatus, the apparatus further comprising a retaining member mounted adjacent said outlet end portion for pivotal movement said member normally being urged to a rest position in which it closes the outlet end portion of the slideway and retains a cap in said slideway positioned for engagement by a receiving portion of a container, whereby when a container travelling in said feed direction engages a cap positioned at the outlet end portion of the slideway continued movement of the container in the feed direction draws the cap from the slideway the cap causing said retaining member to pivot away from the rest position to allow the cap to escape from the slideway positioned on the receiving portion.

In apparatus in accordance with the invention it is desirable that the cap slide from said entrance portion down said wall to said outlet end portion readily.

Preferably, to this end, said wall is inclined at an angle of at least 250 to the horizontal, more preferably between 30 and 600 to the horizontal e.g. about 400 to the horizontal.

Preferably apparatus in accordance with the invention comprises feeding means for feeding caps to the illustrative apparatus. In a further aspect the invention may be considered to provide feeding means as set out below. Suitably the caps may be supplied, in correct orientation i.e. with their openings facing downwardly, to means for feeding a pre-selected number of caps, preferably one at a time into said entrance portion. The apparatus preferably further comprises sensing means adapted to sense the absence of a cap from a sensing position adjacent the outlet end portion and to signal the feeding means to operate to feed said preselected number of caps into said entrance portion.

Suitably the sensing means may comprise a retro-reflex photocell directed at the position which would be occupied by a cap adjacent the outlet end portion of the apparatus. Other sensing means may be used if desired.

Preferably apparatus in accordance with the invention comprises adjusting means positioned downstream of the outlet end portion so that a guide surface thereof, in an operative position, is spaced slightly from a cap correctly positioned on a receiving portion of the container but is adapted to engage a cap which is askew and adjust it to the correct position as the container is propelled past the adjusting means in the feed direction. Preferably the adjusting means is retained in the operative position by the force of gravity but is mounted so that it may readily move upwardly from the operative position in the event that a distorted cap engages the guide surface thereof, to avoid jamming of the apparatus. Suitably a groove extends in the feed direction along a central portion of the guide surface throughout its length; upper surfaces of moulded plastics caps are usually slightly convex and the groove provides a guide passageway for the convex configuration of the upper surface of the cap.

Preferably a terminal portion of said wall, at said outlet end portion, is horizontal or substantially so; thus, as the cap is withdrawn from the outlet end portion, it progressively adopts a generally horizontal position. Preferably, in addition, a lower end portion of the retaining means is angled from the vertical in a downstream direction to facilitate escape of the cap from the outlet end portion and to guide it into said horizontal condition.

There now follows a detailed description to be read with reference to the accompanying drawings of apparatus embodying the invention. It will be realised that this apparatus has been selected for description to illustrate the invention by way of example.

In the accompanying drawings: Figure 1 is a perspective view with parts broken away showing apparatus embodying the invention; Figure 2 is a diagrammatic front view with parts broken away and partly in section of part of the illustrative apparatus; Figure 3 is a side view of part of the illustrative apparatus showing a neck portion of a container engaging a cap; and Figure 4 is a view partly in section of adjusting means of the illustrative apparatus.

The illustrative apparatus comprises a mounting bracket 10 adapted to be mounted on conveying apparatus of a packaging line (not shown). A slideway 12 is secured to the bracket 10 and comprises an entrance portion 14 and an outlet end portion 16 below the entrance portion.

The slideway comprises a lower wall 18 for supporting caps inclined at an angle A (see Figure 2) to the horizontal; conveniently, in the illustrative apparatus the angle A is about 300. The slideway 12 further comprises side walls 20 spaced apart by a width slightly greater than the width of caps to be positioned by the illustrative apparatus. At the outlet end portion 16 of the slideway, an opening 22 is provided, bounded at either side by lip portions 24 which are adapted to support peripheral portions of a cap with the cap positioned over the opening 22 for engagement with a neck portion 26 of a container 28 travelling in a feed direction (indicated by the arrows B in Figures 1 and 2) through the illustrative apparatus.

The illustrative apparatus further comprises retaining means provided by a retaining member 30 mounted adjacent said outlet end portion 16 for pivotal movement about a horizontal pivot 32 carried by the bracket 10.

The retaining member 30 is urged about the pivot 32 under the force of gravity to a rest position in which it closes the outlet end portion of the slideway 12 (see Figures 1 and 2) to thereby retain a cap 34 in the slideway 12 positioned for engagement by the neck 26 of a container 28. An adjusting screw 36 mounted on the retaining member 30 is adapted to engage a portion of the bracket 10 and to act as a stop by which the rest position may be slightly adjusted if necessary.

Parts of the lip portions 24 which at their ends provide a terminal portion of the bottom wall 18 of the slideway 12, are horizontal, or substantially so (see Figures 1 and 2). A lower end portion 38 of the retaining member 30 is angled from the vertical in a downstream direction in feed direction B.

The illustrative apparatus further comprises feeding means 40 for feeding one cap at a time into the entrance portion 14 of the slideway 12. The feeding means comprises a horizontal slideway 42 along which caps 34b, 34c are urged towards a feed position in which a cap 34b is shown in Figure 1 of the drawings. At the feeding position a feeding device is shown, the device being mounted on the bracket 10 and comprising a pneumatic cylinder 44 mounted on the bracket 10 (by means not shown) having secured to a piston rod 46 thereof a pusher block 48. The pusher block 48 is shown in Figure 1 of the drawings in a retracted position and is reciprocable in a direction indicated by the arrow C in Figure 1 of the drawings by the pneumatic cylinder 44.A plate 50 is secured to the block 48 above a floor 43 of the slideway 42, spaced therefrom by a distance sufficient to receive the caps between the floor 43 of the slideway 42 and the plate 50; an edge portion of the plate 50 facing the slideway 42 is upturned to provide a guide to direct caps beneath the plate 50. A downturned lip D2 is provided on the plate 50 at the edge portion thereof opposite the block 48, to prevent caps (as the cap 34b) in the feed position being accidently urged into the entrance of portion 14 of the slideway 12. As can be seen viewing Figure 1, the cap 34b in the feed position abuts a face of the bracket 10 facing the slideway 42 and is positioned between the lip 52 and a pusher face 54 of the block 48.

In order to feed the cap 34b into the entrance portion 14 of the slideway 12, the piston rod 46 is extended from the cylinder 44 by appropriate admission of air to the cylinder thus to move the block 48 towards the slideway 12, the cap 34b being pushed by the pusher face 54 into the entrance portion 14 of the slideway, the plate 50 passing above an upper edge portion of the slideway 12. As the block 48 moves towards the slideway 12, a face 56 of the block 48 passes across the slideway 42 and is engaged by the next cap 34c in the slideway, preventing the cap 34c being moved into the feeding position.After the cap 34b has reached the appropriate position in the slideway 12, the cylinder 44 retracts the block 48, allowing the cap 34e to be pushed by the pressure of succeeding caps in the slideway 42 towards the bracket 10 until it engages the bracket 10 and is stopped in the feeding position between the face 54 and the lip 52.

The illustrative apparatus further comprises sensing means adapted to sense the absence of a cap from a sensing position adjacent the outlet end portion 16 and to signal the pneumatic cylinder 44 to operate to feed a cap into the entrance portion 14 of the slideway 12. In the illustrative apparatus the sensing means comprises a retro-reflex photocell (not shown) mounted to face a cap through an opening 58 in one of the walls 20 of the slideway 12. The cell may be positioned to detect the presence or absence of a cap positioned over the opening 22, retained in place by the retaining member 30, or alternatively may be positioned further up the slideway to detect a second cap, abutting the lowermost cap.This latter position may be adopted where it is necessary to ensure that at least two caps are readily available in the slideway where containers travelling in the feed direction B may pass by in contact with one another. It has been found in practice that two such containers may be in contact; however the sensing means may be positioned to ensure a supply of any desired number of caps in the slideway 12 (commensurate with the length of the slideway 12).

Downstream of the outlet end portion 16 in the feed direction B is positioned adjusting means 60 suspended from a part (not shown) of the bracket 10 by two shafts 62 (broken away). The shafts 62 are freely movable up and down in said part of the bracket 10 and are arranged to be suspended under the force of gravity in an operative position. In this operative position a guide surface 64 of the block 60 is positioned so that it will be spaced slightly from a correctly positioned cap 34 carried on the neck 26 of a container 28 as shown in Figure 2. A leading end face 66 of the block 60 is inclined downwardly in the feed direction B to provide a lead in to the guide surface 64. A groove 68 extends in the feed direction B along a central portion of the guide surface 64 throughout its length.In the operation of the illustrative apparatus a container 28 is propelled in the feed direction B on a conveyor belt past the outlet end portion 16 of the slideway 12. The container 28 is guided so that its neck 26 passes through the opening 22 and engages a downstream portion 35 of a wall of a cap positioned at the outlet end portion 16 (see Figure 2).

Continued movement of the container 28 in the feed direction B draws the cap from the slideway 12 urging the cap 34a against the lowermost portion 38 of the retaining member 30 to pivot the retaining member in the direction of the arrow D away from its rest position thus allowing the cap to escape from the slideway 12 positioned on the neck 26 in correct orientation for presentation to a pressure capping device of the type referred to previously (not shown) by which the cap 34 is snapped into place on the neck 26.

In the illustrative apparatus, a single cap 34 is supplied by the feeding means 40 to the slideway 12 at a time. Thus, each time the sensing means detects the absence of a cap from the outlet end portion of the slideway 12, a signal is passed to cause the pneumatic cylinder 44 to operate to push a further cap into the entrance portion 14 of the slideway 12.

The retaining member is constructed so that only a very light force is applied to the container as it withdraws the cap from the slideway when travelling in the feed direction B, insufficient to displace the container or knock it over as it travels. In order that the force exerted on the container is not too great, the number of caps accommodated in the slideway 12 must be kept to a minimum. Also, care must be taken that as the caps supplied to the entrance portion 14 slide down the bottom wall 18, the momentum generated is not sufficient to allow the caps to escape passed the retaining member 30 out of the outlet end portion 16 of the slideway.

Where apparatus is operated at a fast speed, it may be necessary to keep two or possibly even more, caps in the slideway 12 and as before mentioned the sensing means is appropriately positioned to ensure a satisfactory supply of caps. When a cap is detected at the sensing position, this signals retraction of the feed block 48 to its retracted position, ready to dispense a further cap when signalled to do so.

Should a distorted cap be supplied through the machine, the block 60 may yield upwardly to allow the distorted cap to pass without causing jamming of the illustrative apparatus.

The caps intended to be used with the illustrative apparatus are generally moulded of plastics material and have a slightly domed upper surface: the groove 60 ensures that the caps 34 are correctly oriented, as can be seen from Figure 4.

Caps can be positioned on the necks of containers at a rapid rate, for example 80 to 100 caps per minute using the illustrative apparatus (a typical rate using known apparatus is 60 to 80 caps per minute). Furthermore, the illustrative apparatus is relatively cheap and simple to manufacture and can be utilised with containers of various outline shapes, the illustrative apparatus merely needing to fit the dimensions of the cap to be supplied and to be adjust to the correct position to accommdoate the container to be capped.

The illustrative apparatus is especially intended to apply caps by pressure capping to the neck portions of plastics containers, for example of talc. However, apparatus in accordance with the invention may be used to apply suitable caps to receiving portions of containers for other purposes for example tins having an opening defined by a suitable receiving portion, for example a cylindrical wall.

Although the illustrative apparatus is intended for use with a pressure capping machine, caps which are to be secured in place by other means may also be handled by the illustrative apparatus, for example screw threaded caps: in such cases suitable means other than a pressure capping device must be positioned downstream of the illustrative apparatus to secure the caps.

Claims

1. Apparatus suitable for use in positioning caps over an opening of a container propelled in a feed direction in the operation of the apparatus comprising dispensing means defining a passageway having an entrance portion into which caps may be introduced and an outlet end portion disposed below the entrance portion and positioned in a path along which a receiving portion defining said opening of the container constrained to travel as a container moves in a feed direction, a wall of the outlet end portion having an opening through which the receiving portion is constrained to pass as it travels along said path, the dispensing means further comprising retaining means positioned at the outlet portion of the passageway to retain a cap at the outlet end portion of the passageway positioned over said opening for engagement with the receiving portion of a container travelling along said path, the retaining means being mounted for movement as the receiving portion engaged with the cap travels along said path to allow the cap to escape from the passageway.

2. Apparatus suitable for use in positioning caps on receiving portions of containers over an opening defined by the receiving portion, comprising a slideway of width slightly greater than the caps to be positioned having a wall portion for supporting a cap, an entrance portion at which caps can be introduced into the slideway and an outlet end portion at a lower end portion of the slideway, said wall of the slidway having an opening at said outlet end portion bounded at either side by lip portions adapted to support peripheral portions of a cap with the cap positioned over said opening in the wall of the slideway for engagement with the receiving portion of a container travelling in a feed direction through the apparatus, the apparatus further comprising a retaining member mounted adjacent said outlet end portion for pivotal movement said member normally being urged to a rest position in which it closes the outlet end portion of the slideway and retains a cap in said slideway positioned for engagement by a receiving portion of a container, whereby when a container travelling in said feed direction engages a cap positioned at the outlet end portion of the slideway continued movement of the container in the feed direction draws the cap from the slideway the cap causing said retaining member to pivot away from the rest position to allow the cap to escape from the slideway positioned on the receiving portion.

3. Apparatus according to either one of Claims 1 and 2 wherein said wall is inclined at an angle of at least 250 to the horizontal.

4. Apparatus according to Claim 3 wherein said wall is inclined at an angle of between 300 and 600 to the horizontal.

5. Apparatus according to any one of the preceding claims comprising feeding means for feeding a preselected number of caps at a time into said entrance portion.

6. Apparatus according to Claim 5 wherein said feeding means is adapted to feed one cap at a time into said entrance portion.

7. Apparatus according to either one of Claims 5 and 6 comprising sensing means adapted to sense the absence of a cap from a sensing position adjacent the outlet end portion and to signal the feeding means to operate to feed said pre-selected number of caps into said entrance portion.

8. Apparatus according to any one of the preceding claims comprising adjusting means positioned downstream of said outlet end portion so that a guide surface thereof is, in an operating position, spaced slightly from a cap correctly positioned on a receiving portion of a container but adapted to engage a cap which is askew and adjust it to the correct position as the container is propelled past said adjusting means in the feed direction.

9. Apparatus according to Claim 8 wherein said adjusting means is movable upwardly from said operative position.

10. Apparatus according to either one of Claims 8 and 9 comprising a groove extending in the feed direction along a central portion of the guide surface throughout its length.

11. Apparatus according to any one of the preceding claims wherein a lower end portion of the retaining means is angled from the vertical in a downstream direction.

12. Apparatus according to any one of the preceding claims wherein said terminal portion of said wall, at said outlet end portion is horizontal, or substantially so.

13. Apparatus suitable for use in applying caps to necks of containers constructed arranged and adapted to operate substantially as hereinbefore described with reference to the accompanying drawings.