GB2189226A - Label splicing machine - Google Patents

Abstract

A splicing mechanism for use in splicing webs comprises a splicing station 9 through which the web 2 is fed, first holding means 16 to receive and hold one web 2 stationary in the web splicing station, web severing means 18 for severing said one web held by the web holding means to release an upstream portion 23 of the web with respect to the holding means, further holding means 17 for holding a self-adhesive end portion 15 of a further web 13 to be fed by the feeding mechanism and means 22 (not shown) to move the first holding means and with it the severed downstream end 41 of said one web towards the further holding means to apply said downstream end of the one web to the adhesive end portion of the further web. The mechanism allows splicing to be completed within a dwell period of a discontinuous web transport mechanism supplying labels carried by the web to a labelling machine. <IMAGE>

Description

SPECIFICATION Improvements in or relating to web splicing This invention relates to web splicing and in particular but not exclusively to a splicing mechanism and a web transport mechanism for feeding a label carrying web to a labelling machine.

It is known for labelling machines to be supplied with labels by means of a transport mechanism feeding a continuous web on which labels are carried. Since the label carrying webs are prepared in finite lengths it is necessary for successive lengths of web to be spliced in order to provide a continuous supply of labels to the machine. A problem exists in that the splicing operation requires the web to be held stationary so that both the transport mechanism and the labelling machine must be stopped during the splicing operation.

This is particularly disadvantageous when using high speed labelling machines and relatively large labels such that frequent splices are required or where particular thick labels are used such that the available web in a reel of given diameter is of limited length.

According to the present invention there is disclosed a splicing mechanism for use in splicing webs in a web transport mechanism comprising a splicing station through which the web is fed, first holding means to receive and hold one web stationary in the web splicing station, web severing means for severing said one web held by the web holding means to release an upstream portion of the web with respect to the holding means, further holding means for holding a self adhesive end portion of a further web to be fed by the feeding mechanism and means to move the first holding means and with it the severed downstream end of said one web towards the further holding means to apply said downstream end of the one web to the adhesive end portion of the further web.

Preferably the severing means includes a knife and preferably operates by action of the first holding means urging the web into contact with the stationary knife. An advantage of such an arrangement is that a splice may be completed rapidly and with the minimum of moving parts.

Advantageously a splicing mechanism includes knife displacing means for providing reciprocating movement of the knife into and out of the splicing station, the knife being displaceable in a direction substantially parallel to the plane of the web. The further web may then assume after completion of the splicing operation the position formerly occupied by the said one web by movement from the further holding means towards the first holding means, which movement would otherwise be obstructed by the presence of the knife.

Conveniently the first holding means includes a recess into which the knife extends during at least part of the severing operation.

This assists the cutting action and prevents the presence of the knife obstructing the movement of the first holding means towards the further holding means.

Preferably at least one of the first and the further holding means includes suction means.

Advantageously the splicing mechanism includes means for moving the further holding means between its operating position in the splicing station and a loading position in which the end portion of the further web may be loaded onto the further holding means such that the further holding means may then be returned to its operating position with the end portion held in place.

Conveniently the means for moving the further holding means includes a pivot about which the further holding means is pivotally mounted.

According to a further aspect of the invention there is disclosed a web transport mechanism comprising means for feeding a label carrying web step by step to a labelling machine to deliver a predetermined number of labels thereto at each step, control means for actuating the web feed means to advance one step in response to a signal from a labelling machine and a splicing mechanism for splicing a further web to the web currently being supplied between said step by step feeds of the web to avoid disruption of the label supply.

Preferably the web transport mechanism includes a label sensing means connected to the control means for sensing a label at a position along the feed path which is downstream of the splicing mechanism, the arrangement being such that the control means initiates feeding of the web upon receipt of a signal from the labelling machine and stops the feeding of the web after the passing of a predetermined number of labels has been detected by the label sensing means.

Preferably the web transport mechanism includes means for adjusting the path length between the splicing mechanism and the label sensing means. The path length may then be adjusted so that the splicing mechanism may be arranged to sever the web at a position between adjacent labels before splicing a further web to the downstream portion of the first web and this path length may be adjusted in order to accommodate the splicing of webs having labels of different size.

Advantageously a web transport mechanism includes a web supply level sensor for actuating the splicing mechanism upon depletion of the finite web supply. The splicing of webs may therefore be initiated automatically without receiving the attention of an operator.

Advantageously the web is supplied from a first reel at a first location and the further web is supplied from a second reel at a second location and the web transport mechanism fur ther includes means for moving the second reel to the first location and the first reel to the second location upon completion of a splicing operation. The depleted first reel may then be replaced by a full reel the end of which may be loaded onto the further holding means in readiness for splicing when the second reel is depleted.

Conveniently the web transport mechanism includes indicating means for indicating to an operator the completion of a splicing operation. The operator is then alerted to the need for replacing the depleted first reel by a full reel the end of which is to be loaded onto the further holding means in readiness for the next splicing operation.

Preferably a web transport mechanism as hereinbefore disclosed includes a splicing mechanism as hereinbefore disclosed since such a splicing mechanism is particularly adapted for completing a splicing operation within a short period of time.

The predetermined number of labels may be unity in which case labels are fed one by one to the labelling machine. Alternatively the number may be greater than unity so that a plurality of labels are fed in a single step following which the web feeding means will stop. The means for generating the signal for starting the web feeding means may then include a label counter such that the signal is generated after a corresponding plurality of labels has been consumed.

Particular embodiments of the invention will now be disclosed by way of example only and with reference to the accompanying drawings of which Figure 1 is a front elevation of a web transport mechanism including a splicing mechanism in accordance with the present invention, Figure 2 is a front elevation of the splicing mechanism of Fig. 1 at the beginning of a splicing operation, Figure 3 is a similar view of the splicing mechanism of Fig. 2 at a later stage of the splicing operation, Figure 4 is a plan view of the web transport mechanism of Fig. 1, and Figure 5 is a front elevation of an alternative splicing mechanism in which the further holding means is pivotally mounted.

In Figs. 1 and 4 a web transport mechanism 1 feeds a web 2 to a labelling machine 3 from a first reel 4. A web feed means 5 feeds the web 2 having pinch rollers 6 driven by an electric motor 7 through an electromagnetic clutch and brake mechanism to enable the drive transmitted to the pinch rollers 6 to be started and stopped on demand from a control means 8 so that the web may be fed with a step by step motion.

The web 2 is fed through a splicing station 9 which is upstream of the pinch rollers 6 and a label sensor 10 is positioned downstream of the splicing station. The label sensor 10 comprises a photoelectric sensor which is mounted so as to be slideably adjusted along the path of the web 2 in order to provide means for adjusting the path length between the sensor and the splicing station 9. The label sensor 10 is connected to the control means 8 and indicates to the control means the presence or absence of a label on the web 2.A photoelectric web sensor 11 is located downstream of the splicing station 9 and is connected to the control means 8 to indicate the presence or absence of a web and a similarly located photoelectric double web sensor 12 is arranged to detect any double thickness of web to the control means, the sensors 11 and 12 being present to detect fault conditions arising either from a web break or a failure of the splicing station 9 requiring the web feed to be stopped.

A further web 13 is supplied from a second reel 14 and has a self adhesive end portion 15 which is held in the splicing station 9 in readiness for being spliced to the first web 2.

The splicing station 9 has a first holding means 16 which is adjacent to the web 2 in the normal running position as shown in Fig. 1 before the commencement of a splicing operation with the label carrying side of the web facing the first holding means. A further holding means 17 is disposed on the opposite side of the web 2 and a knife 18 is disposed between the further holding means and the web so as to extend in a direction parallel to the plane of the web and transversely with respect to the direction of the web feed. The first holding means 16 has a perforate face 19 facing the web 2 through which suction may be applied in order to hold the web as required during splicing and the face 19 includes a recess 20 extending in parallel alignment with the knife 18.The further holding means 17 has a perforate face 21 through which suction may be applied for holding the further web 13 with the adhesive end portion 15 in readiness for splicing.

The splicing station 9 includes reciprocating means 22 for moving the first holding means 16 in a direction at right angles to the plane of the web and into and out of contact with the further holding means 17. In the position shown in Fig. 2 the first holding means 16 is in contact with the web 2 whilst the web is stationary and the web is held against the perforate face 19 by suction on either side of the recess 20. Continued movement towards the further holding means 17 brings the web 2 into contact with the knife 18 and further continued movement in this direction severs the web as the knife extends into the recess 20. An upstream portion 23 of the web is thereby released so that no web from the first reel 4 will thereafter be fed forward by action of the web feed means 5.Upon completion of the splicing operation suction applied to the face 19 is turned off so that the upstream portion 23 will fall from the splicing station 9.

The knife 18 is mounted on a retracting mechanism 24 for providing reciprocating movement of the knife into and out of the splicing station 9 in a direction parallel to the plane of the web 2 and transverse to the feed direction. The retracting mechanism 24 as seen in Fig. 4 includes rollers 25 running on a rail 26 with the knife been driven along the rail by means of a pneumatic ram 27. Similarly the first holding means 16 has a reciprocating means 22 including rollers 28 and a pneumatic ram 29. Fig. 4 also shows the motor 7 of the web feed means 5 with the pinch rollers 6 feeding the web 2.

As seen in Fig. 1 the first and second reels 4 and 14 respectively are rotably mounted in a frame 31 such that the second reel 14 is above the first reel 4. The frame 31 is rotatable about a horizontal axis 32 so that by rotation of the frame through 180 degrees in a clockwise direction as viewed in the drawing the first and second reels may change position. The frame 31 also include web tensioning and braking devices 33 to ensure smooth web delivery.

The frame 31 also includes a photoelectric sensor 34 for detecting whether the remaining web of the first reel 4 has reached a low level and this sensor is connected to the control means 8 such that when the supply of web 2 runs out the splicing operation is initiated during the next stationary period of web feeding.

A removable front guard 35 prevents operator access to the splicing mechanism whilst the knife 18 is extended into the splicing station. A micro switch 36 is provided to detect the closed position of the guard 35 and this is connected to the control means 8 so that the knife 18 may be retracted whenever the guard is lifted for the operator to obtain access to the splicing station 9. A foot switch 37 is connected to the further holding means 17 so as to enable an operator to turn on or off the suction applied through the perforate face 21, the switch 37 comprising a microswitch controlling the vacuum supply. A template 38 is also provided adjacent to the splicing station 9 whereby an operator may attach an adhesive patch to the free end of a further web 13 in order to form the adhesive end portion 15.

An indicator light 39 is provided for indicating to the operator that a splicing operation has been completed and this light will be extinguished on closing the guard 35, the micro switch 36 at this instant providing a signal to the control means 8. The guard 35 is closed again only after a new further web has been loaded onto the further holding means 17 at which point a logic signal is generated in the control means 8 representing that a further web is available for splicing.

The control means 8 includes logic circuits controlling the sequence of operation of each of the active elements of the transport mechanism 1. The control means 8 will command the drive to the pinch rollers 6 to be engaged if it receives a demand signal from the labelling machine 3 provided that there is no web fault indicated by either of sensors 11 and 12.

The web will then feed forward until a signal from the label sensor 10 indicates that one label has been fed forward at which point the control means 8 will command the drive to the pinch rollers to be disengaged and the web arrested. In this way the web transport mechanism 1 feeds the web in a step by step motion to deliver labels one by one to the labelling machine.

During any period in which the web is stationary, a low web level signal received from the sensor 34 will result in the control means initiating a splicing operation provided that micro switch 36 indicates that the guard has been closed. The splicing operation is initiated by actuating the pneumatic ram 29 to move the first holding means 16, retracting the knife 18 after cutting the web by actuating the retracting mechanism 24 and reverse actuating the ram 29 after contact between the first holding means 16 and the further holding means 17.

The first holding means 16, the further holding means 17, the knife 18 and their associated reciprocating means therefore together comprise a splicing mechanism 40 which operates by holding and cutting the web 2 to release an upstream portion 23 of the web and then press a downstream portion 41 of the web into contact with a self adhesive end portion 15 of a further web 13 which is held in a further holding means 17. The splicing operation is completed during a period in which the web is stationary and before the arrival of the next demand signal from the labelling machine so that there is no disruption to the label supply. Immediately after the splice the indicator light is turned on and alterts the operator that action must be taken to prime the splicing station 9 with a further web.The operator rotates the frame 31 so that web is being drawn from the lower of the two reels carried on the frame and the frame is then locked in position. A fresh reel of web is loaded into the frame to form an upper most reel from which a length of web is threaded around guide rollers 42 in preparation for being fed to the splicing station. The end of this further web is prepared by the operator using the template 38 in order to trim the web to have a square end and attach a self adhesive splicing tape 43 in order to form a self adhesive end portion 15 of the further web.

The guard 35 is lifted and the foot switch 37 operated to shut off the suction provided by the perforate face 21 of the further holding means 17. The adhesive end portion 15 is then positioned on the face 21 and the suction reinstated by means of the foot switch 37 so that the end portion 15 is held in place. The guard is then closed at which point the indicated light is extinguished and the knife 18 is moved forward into the splicing station 9 into its operative position.

The priming of the splicing mechanism 40 is then completed.

When the supply of web once again becomes sufficiently depleted to activate the low web level sensor 34 then the splicing operation will be initiated at the same time as the web feed is halted following delivery of a label.

An alternative splicing mechanism 44 is shown in Fig. 5 in which the further holding means 17 is pivotally mounted about a pivot 45 to enable the further holding means to be moved into a position at which the face 21 is more readily assessable for applying the adhesive end portion 15 of a further web.

In a further alternative arrangement the suction applied to the face 19 remains turned on on completion of the splicing operation so that the upstream portion 23 of the web 2 is held in the splicing station 9 until forceably removed when the frame 31 is rotated during changing of the reel positions.

A transport mechanism in accordance with the present invention may form an integral part of the labelling machine or alternatively may be a stand alone item for use with a variety of labelling machines. The label demand signal may be derived from a sensor attachable to the labelling machine to detect a labelling event or from a purpose in-built sensor incorporated in the labelling machine. The web feed path to the labelling machine may require the inclusion of a turn bar (not shown) inclined at 45 degrees to both the horizontal and to the web feed direction so that the plane of the web is rotated from the horizontal to the vertical after turning around the bar.

The web transport mechanism may be adapted to feed a plurality of labels at each step by adapting the control means logic to count a predetermined number of labels as sensed by the label sensor 10. The pinch roller drive is then engaged on receipt of a demand signal from the labelling machine and disengaged after the predetermined number of labels has passed. The demand signal must then be generated only after a corresponding plurality of labels have been consumed by the labelling machine so that a counter is similarly included in the demand signal generating means.

Claims (17)

1. A splicing mechanism for use in splicing webs in a web transport mechanism comprising a splicing station through which the web is fed, first holding means to receive and hold one web stationary in the web splicing station, web severing means for severing said one web held by the web holding means to release an upstream portion of the web with respect to the holding means, further holding means for holding a self adhesive end portion of a further web to be fed by the feeding mechanism and means to move the first holding means and with it the severed downstream end of said one web towards the further holding means to apply said downstream end of the one web to the adhesive end portion of the further web.

2. A splicing mechanism as claimed in claim 1 wherein the severing means includes a knife.

3. A splicing mechanism as claimed in claim 2 wherein the severing means operates by action of the first holding means urging the web into contact with the stationary knife.

4. A splicing mechanism as claimed in claim 3 including knife displacing means for providing reciprocating movement of the knife into and out of the splicing station, the knife being displaceable in a direction substantially parallel to the plane of the web.

5. A splicing mechanism as claimed in any preceding claim wherein the first holding means includes a recess into which the knife extends during at least part of the severing operation.

6. A splicing mechanism as claimed in any preceding claim wherein at least one of the first and the further holding means include suction means.

7. A splicing mechanism as claimed in any preceding claim including means for moving the further holding means between its operating position in the splicing station and a loading position in which the end portion of the further web may be loaded onto the further holding means such that the further holding means may then be returned to its operating position with the end portion held in place.

8. A splicing mechanism as claimed in claim 7 wherein the means for moving the further holding means includes a pivot about which the further holding means is pivotally mounted.

9. A web transport mechansim comprising means for feeding a label carrying web step by step to a labelling machine to deliver a predetermined number of labels thereto at each step, control means for actuating the web feed means to advance one step in response to a signal from a labelling machine and a splicing mechanism for splicing a further web to the web currently being supplied between said step by step feeds of the web to avoid disruption of the label supply.

10. A web transport mechanism as claimed in claim 9 including a label sensing means connected to the control means, for sensing a label at a position along the feed path which is downstream of the splicing mechanism the arrangement being such that the control means initiates feeding of the web upon receipt of a signal from the labelling ma chine and stops the feeding of the web after the passing of a predetermined number of labels has been detected by the label sensing means.

11. A web transport mechanism as claimed in claim 10 including means for adjusting the path length between the splicing mechanism and the label sensing means.

12. A web transport mechanism as claimed in either of claims 9, 10 or 11 including a web supply level sensor for actuating the splicing mechanism upon depletion of the web supply.

13. A web transport mechanism as claimed in any of claims 9 to 12 in which the web is supplied from a first reel at a first location and the further web is supplied from a second reel at a second location and further includes means for moving the second reel to the first location and the first reel to the second location upon completion of a splicing operation.

14. A web transport mechanism as claimed in any of claim 9 to 13 including indicating means for indicating to an operator the completion of a splicing operation.

15. A web transport mechanism as claimed in any of claims 9 to 14 including a splicing mechanism as claimed in any of claims 1 to 8.

16. A splicing mechanism substantially as hereinbefore described with reference to and as shown in Figs. 1 to 4 of the accompanying drawings or as modified in Fig. 5.

17. A web transport mechanism substantially as hereinbefore described with reference to and as shown in Figs. 1 and 4 of the accompanying drawings.