GB2388831A

GB2388831A - Sachet applicator

Info

Publication number: GB2388831A
Application number: GB0210126A
Authority: GB
Inventors: Michael John Smith
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-05-02
Filing date: 2002-05-02
Publication date: 2003-11-26
Also published as: GB0210126D0

Abstract

A mechanism for attaching sachets to articles such as wrapped bunches of flowers or take-away food containers includes means 50 for applying adhesive to the sachets. The adhesive applicator station 23 may have left and right transporter means such as opposed drive belts for gripping the side edges of each sachet and passing it through the station, the adhesive applying means 50 being located between the left and right transporter means. Successive sachets may be fed from a source such as a reel 20 through sensing means 21 and drive rollers 22 and past sensing means 51 associated with the adhesive applicator station 23, to an ejector station 24. The mechanism is controlled in response to the sensing means 21, 51 so that each successive sachet following application of adhesive to its underside is separated at a line of weakness from the following sachets and ejected downwardly at station 24 onto the article below. The location of sensing means 21 is adjustable for different sachet sizes.

Description

1 238883 1

Attaching Sachets to Articles 5 The present invention relates to apparatus and methods for attaching sachets to articles. A particular application is to the attachment of plant food sachets to wrapped bunches of flowers; for this, the present invention can usefully be used in combination with flower wrapping machinery of the type described in our earlier patent application no. WO 01/10634 Al. However. the uses of the n present invention are not limited to flower wrapping,. and extend for example to the attachment of sachets of food flavounngs or sauces to take- away food containers. Traditionally. plant food sachets have been attached using conventional s plastic sticky tape. In many cases the tape used to bind the base of the wrap also secures the sachet. The bunch of flowers in typically wrapped in a cone-shaped wrap of paper or similar material. The most common practice is to gather the base of the wrap by hand and the orbit a tape reel by hand around the gathered flower stems, wrap, and sachet. Van den Berg has developed a machine that to binds the sachet at the gathered base using elasticated cord, while Arnie BV have a mechanism that orbits a tape reel around a presented bouquet in a similar manner to the manual technique just described.

A sachet applicator machine has been described in WO 02/06124 Al. A 25 connected sequence of sachets is moved along a transport path past a first station where Preferably a double-sided sticky tape is applied to the sequence of sachets.

The separating paper is then diverted from the transport path, and the position of the sachets is sensed at a second station where the sachets are separated from each other. This system enables the sachet to be secured in substantially any location 0 on the wrap. The flower vendor can therefore locate the sachets in a readily visible location on the wraps.

The object of the present invention is to provide an improved technique for applying sachets such as plant food sachets to articles such as wrapped bunched of flowers. According to the invention there is provided a sachet applicator comprising an adhesive applicator station having left and right transporter means for gripping the sides of a sachet and passing it through the station, and adhesive applying means located between the left and right transporter means. Preferably the station lo includes sensor means for sensing the position of the sachet and controlling the adhesive applying means. Preferably the transporter means comprise bands passing round rollers. Preferably the transporter means operate so as to eject the sachet with applied adhesive on the fly. Preferably the applicator station is preceded by sachet providing means comprising drive means for feeding a is continuous strip of sachets separated by perforations and capable of being started to feed a sachet forward to the applicator station and stopped to hold the strip stationery such that the applicator station separates the sachet from the following sachet. Preferably the sachet providing means includes sensor means for sensing the positions of sachets on the strip. Preferably the applicator station feeds an :e ejector station comprising a pair of flaps on which the sachet can rest and having a gap between them between which the adhesive will lie, and an ejector plate above the flaps and operable to drive the sachet through between the flaps. The flaps may be flexible or mechanically operable to open to allow ejection of the sachet.

A sachet applicator machine embodying the invention will now be described, by way of example, with reference to the drawings, in which: Fig. I shows a strip of sachets; Fig. 2 is a side view of the applicator machine; and Fig. 3 is a perspective view of the machine.

( 3 Sachets are used for a variety of applications, from carrying a small volume of sauce or spice to accompany some pre-prepared vegetables or "ready meal' to carrying fertiliser or chemical food for flowers or plants. The present apparatus is concerned with around the automatic application of these sachets and their s attachment to the article to be sold.

The sachets are normally formed by a continuous process where a continuous strip of plastic film material is curved by formers as it is fed through the system such that a U and then a tubular section are created. (Alternatively lo two layers of plastic film material may be joined together one above the other with side seams to create a tube.) As the tubular section is closed it is sealed, generally using heat welding. As the process continues, a second device, generally a heated bar, clamps and seals the created tube at regular intervals, thus creating the bags or sachets. A nozzle placed inside the tube at the region where it is formed fills the t5 tube with the appropriate product as the associated mechanisms create and seal each bag in turn. The result is a string of small bags; if desired, a multiple string may be produced by running several lines in parallel. Fig. 1 depicts a typical single string 10 of sachets I I so produced, each sachet being closed by a seal line 12 around its periphery.

The normal cutting point is the breaking point 13, at which the manufacturing machine normally separates each of the sachets prior to dropping them into a box for supply to the customer. For present purposes a continuous string is required, so the normal cutter is replaced by a perforation cutter that :5 leaves small slots in the material but does not break the string.

Figs. 2 and 3 show the general layout of the apparatus, which comprises a sachet source 20, sensing means 21, a pair of drive rollers 22, an adhesive applicator station 23, and an ejector station 24 in sequence.

f 4 The sachet source 20 is shown for simplicity as a reel which carries a long strip of sachets of the form shown in Fig. I. Instead of a reel attached to the apparatus, the sachets can of course be fed from a remote reel via a feed roller in place of the reel 2O, either directly or via a further feed roller located above the position of the reel 20. The use of such feed rollers is desirable to help to ensure the movement of the sachet's contents to one end of the sachet, providing better definition for Me sensing system 21. Alternatively, a pair of rollers (not shown) can be provided at the outlet of the reel 20 for this purpose.

n The sensor mechanism 21 comprises a single pair of rollers 30 and 31, mounted on arms 32 and 33 pivotally mounted at their left-hand ends so that the rollers can move towards and way from each other. A spring 34 is located across the two arms to pull them together, and a switch 35 is also mounted between the arms. When a sachet is pulled between Me arms, the contents of the sachet will s push the arms apart, operating the switch 35. This allows simple location detection of the perforation by sensing the sachet or bag thickness.

Typically, sachets have a location mark printed into the pattern of the film material, this mark being used in conjunction with a sensor to correctly locate the to sachet for cutting etc. A sensor of this type can of course be used instead of the sensor mechanism 21.

The stung of sachets is pulled through the sensing means 21 by the pair of stop/start rubber drive rollers 22. The rollers 21 are driven either by a separate Is electric motor or by a clutch/brake take-off Mom the drive for the adhesive applicator station 23. When a sachet is required for application, the rollers 22 are switched on until the sensor indicates the correct location has been reached; th brake is then applied to stop the string, suddenly with the perforation inline with the break line 13. The roller beltJband set in die adhesive applicator station 23 so operate continuously, so when the drive rollers 22 are stopped, die sachet stung is

snapped along the perforation line and the single sachet continues its path through the adhesive applicator station 23 to the ejection station 24.

The sensor mechanism 21 is mounted for sliding movement along the line s of movement of the strip 10, and can be clamped in position by clamps 36 forming part of the sensor mechanism and protruding through a slot 37. This allows different sachet sizes to be catered for by adjusting the sensor location.

Adjustment is made such that the break point or line 13 is maintained, with the sensor being positioned appropriately.

lo The lower roller of the rollers 22 is on a fixed mounting. whereas the upper roller of this pair of rollers is on a spring mounting. This allows the gap between these rollers to be forced open by the sachet passing through the roller pair. The spring mounting maintains the appropriate pinch between the rollers so that they do not slip or skid on the sachets' surface. Rubber rollers, belts, or bands are used as required to maintain a high coefficient of friction or grip against the sachet.

In the adhesive applicator station 23, belts or bands have been adopted to drive the sachet through the station. This is because a gap along the centre of the to sachet has to be provided so that adhesive can be applied. Specifically, there is a pair of front and back (or left and right) upper belts 41 passing around rollers 42 and 43, a front or left lower belt 45 passing around rollers 46-49, and a rear or light lower belt 44 passing around rollers 46 and 49. Roller 43 is spring-mounted like the upper roller of roller pair 22. A sensor 51 is mounted above the sachet 25 path with a sensor reflector 52 below the path, and an adhesive An 50 is mounted below the sachet path. (The larger length of band 45 is to accommodate the adhesive gun.) The belts seize a sachet by its edges or borders and convey it through the so station 23. The sensor 51 detects the presence of the sachet in the station and switches the gun 50 on at the appropriate moment to apply adhesive along the

( 6 centre line of the sachet. A tone delay may be included if required dependent on the relative locations and speeds of the various elements. The sensor is thus used to control the application of the adhesives starting and stopping the flow as appropriate to achieve the length of adhesive string required. The adhesive may 5 be of any convenient type, though currently hot melt is preferred, and may be applied as a cord or a spray to suit the final application.

The rollers and belts or bands of the station 23 travel quite quickly, so that when the sachet has passed through the station, it is ejected fiom the belts and lo "flies" a short distance before it comes to rest in the ejector station 24. This comprises an upper ejector plate 55 and a lower pair of flaps 56 which support the sachet from either side avoiding contact with the glue layer - side cheeks (not shown) are used to control the sachet's location. The flaps are flexible and supported along their outside edges (parallel to the path of the sachets).

At the appropriate time, the ejector plate 55 travels at a high rate of acceleration - greater than the pull of gravity. The activation of the ejector plate may be by means of pneumatic cylinder, servo motor driven linear mechanism 57, or other suitable technique. When activated, it pushes the sachet past the flaps 56 to and continues accelerating until the end of its stroke, when it decelerates abruptly and returns to its start position before another sachet is snapped from the string.

As the ejector decelerates, the sachet separates and flies a short distance before it collides with the target object (not shown) beneath the apparatus. As a result, the adhesive is forced into contact under the pressure of the sachet's weight and :s velocity, at which point it secures the sachet to its intended surface.

Instead of the passively operating flaps just described, the flaps may alternatively be mounted on rods which can be rotated to rotate the flaps downwards and outwards away from the sachet position.

lo

! 7 Obviously the sachets could be applied to the articles to receive them direct from the station 23.

1 he applicator shown is designed for use over horizontal surfaces such as conveyors; however, the sachets May be applied at any angle with this mechanism by simple rotation and modification to the infeed rollers as appropriate.

The present technique can be used with longitudinal cutters and appropriate mechanisms to enable the apparatus to work with multiple strings of sachets fed as lo a multi-column strip.

2j Claims

Any novel and inventive feature or combination of features specifically so disclosed herein within the meaning of Article 4H of the International Convention (Paris Convention).

Claims

( Claims A mechanism for attaching sachets to articles characterized by a

means of applying adhesive to an individual sachet, string or multiple strings of sachets, sequentially separating each sachet and applying the adhesive coated face of the sachet to an article in order to attach it in a desired position to that article.

A mechanism for attaching sachets to articles charactenzedin that sachets or bags containing any solid, granular material, powder or liquid substance are coated with any volume or area of adhesive and subsequently applied to another object or article using the adhesive as a temporary or permanent attachment means.

A mechanism for attaching sachets to articles characterized by the addition of an adhesive to one or more faces of the sachet for the purpose of attaching that sachet to another object or article.

A mechanism for attaching sachets to articles characterized by a method of transporting, gripping and separating the sachets from their string (10) after having sensed the correct position of the perforation or cutting point using a sensing means.

A mechanism for attaching sachets to articles characterized by a method of transporting the detached sachets past an adhesive application means without the risk adhesive contamination to the transportation means.

A mechanism for attaching sachets to articles characterized by a method of handling sachets with adhesive applied and subsequently attaching that sachet to the surface of a chosen article.