Apparatus for and a method of welding a reinforcing member to a bag-like means

Abstract: Apparatus for welding a reinforcing member to a bag like member comprising a hollow mandrel (18), the hollow mandrel (18) having an outer surface with the groove (17) shaped to the form of the reinforcing member, means (19) for applying a closed end of the bag like member into the hollow mandrel (18) and an open end of the bag like member over the hollow mandrel (18) at the outer surface with the groove (17), the reinforcing member being located with respect to the bag like member at the position of the groove (17) and means for welding (51) the reinforcing member to the bag like member.

Description: This invention relates to apparatus for and a method of welding a reinforcing member to a bag like member. It is known from FR-A-1136378 to provide an apparatus for welding a reinforcing member 78 to a bag like member 74 comprising a hollow mandrel 71 having an outer surface and means for welding the reinforcing member to the bag like member. The present invention is characterised in that the outer surface of the mandrel has a groove shaped to the form of the reinforcing member; means are provided for applying the closed end of the bag like member into the hollow mandrel and an open end of the bag like member over the hollow member at the outer surface of the groove, the reinforcing member being located with respect to the bag like member at the position of the groove. Preferably the means for applying the bag like member include means for gripping the bag like member at a plurality of sites on a circumference of the open end of the bag like member. The means for applying the bag like member may include means for expanding the open end of the bag like member, and also the means for welding the reinforcing member may include means for applying heat and/or pressure. The reinforcing member may be located in the groove prior to the application of the bag like member. The means for gripping the bag like member may include a plurality of prongs positionable within the open end of the bag like member and cam means for moving the prongs from a position in which they are separated from one another to expand the open end of the bag like member. The gripper prongs may be in the form of captively held rollers rotatable on axes parallel to one another and to the bag like member. The prongs in the expanded condition preferably provide an opening therein, and the welding means is in the form of a head which can pass through the said opening. Means may also be provided for removing surplus material at the open end of the bag like means extending beyond the reinforcing member. The means for removing the surplus material may be provided by movement of the prongs after welding has taken place. One or more gas injectors may be provided to open and/or maintain open the open end of the bag like member. The mandrel may be mounted on a turntable which rotates the mandrel to operational positions, in which the bag like material is applied thereto, welded thereto and removed therefrom. In one convenient arrangement the bag like member and the reinforcing members are annular. According to another aspect of the present invention is a reinforcing member welded to a bag like member to form a contraceptive sheath. The contraceptive sheath is preferably for female use. According to another aspect of the present invention is a method for welding a reinforcing member to a bag like member. In this connection it is also known from FR-A-1136378 mentioned above to provide a method for welding a reinforcing member to a bag like member 74 comprising the steps of applying into a hollow mandrel 71 having an outer surface a closed end of the bag like member and an open end of the bag like member over the hollow mandrel of the outer surface thereof, and welding the reinforcing member to the bag like member. According to this aspect of the present invention the method is characterised in that the outer surface of the mandrel has a groove shaped to the form of a reinforcing member; the reinforcing member is located with respect to the bag like member at the position of the groove. Preferably the step of applying the bag like member includes gripping the bag like member at a plurality of sites on a circumference of the open end of the bag like member and moreover, the step of applying the bag like member may include expanding the open end of the bag like member. In addition the step of welding the reinforcing member may include applying heat and/or pressure. Conveniently the method also includes a step of removing surplus material at the open end of the bag like means extending beyond the reinforcing member and the removal of the surplus material may be performed by movement of prongs after welding has taken place. The invention may be performed in various ways and one specific embodiment will now be describe by way of example and with reference to the accompanying drawings in which : Figure 1 - is a general arrangement view of apparatus according to the invention; Figure 2 - shows in more detail an O-ring pick up arrangement; Figure 3 - shows a bag like means about to descend down a chute to an O-ring weld station; Figure 4 - shows the bag like means during its descent; Figure 5 - shows the welding head about to move into position to weld the ring to the bag like means; Figure 6 - shows the welding head in position; Figure 7 - shows the completed bag-like means ready for removal; Figure 8 - shows the plan view a gripper finger assembly; Figure 9 - is a side view of Figure 8; and Figure 10 - is a detail view of a gripper finger. Figure 1 illustrates a general arrangement and the numbers shown in the arrows correspond to the arrangement shown in Figures 2 to 7 described more fully below. In Figure 1, there is shown at 10 a series of bag-like means attached to backing paper as described in the Applicant's co-pending UK Patent Application No. 92 16023.3. Figure 2 illustrates an O-ring pick head 11. The O-ring pick head 11 is arranged to pick an O-ring from the top of a stack of O-rings in an O-ring feeder tube 12. The O-ring pick head in this position is shown in dashed or broken lines and moves downwardly on the top of the stack of O-rings. An O-ring gripper 13 releases a single O-ring and the O-ring pick head 11 then has suction applied to it. The section applied to the O-ring pick head 11 causes the O-ring to be sucked or pulled by a vacuum into a corresponding groove in the underside of the O-ring pick head 11. The O-ring gripper 13 contacts and retains the remaining O-rings on the tube. The arrangement is such that the O-rings are raised upwardly so that the O-ring gripper 13 can release the O-rings one at a time. When the O-ring pick head 11 has lifted the top ring, the O-ring pick head 11 then rotates so as to be over the first position of a four position rotary turntable 16. The four positions of the rotary turntable 16 are indexed at 90° to one another. In the first position, the O-ring pick head 11 moves downwardly to press an O-ring into an annular groove 17 in a pot 18 located on the rotary turntable 16. The pot 18 is open at both ends in the preferred embodiment. Suction is then applied to the annular groove 17 at the top of the pot 18. At the same time, the suction is terminated from the O-ring pick head 11 and a supply of compressed air is supplied through the O-ring pick head 11 to assist in transferring the O-ring from the O-ring pick head 11 to the pot 18 on the rotary turntable 16. Sensor means (not shown) can be present for verifying the presence of an O-ring on the annular groove 17. If no O-ring is on the annular groove 17, the O-ring pick head 11 returns to transfer another O-ring. When an O-ring has been satisfactorily placed in the annular groove 17 at the top of the pot 18, the O-ring pick head 11 swings away to return to the position above the O-ring feeder tube 12 in preparation for the start of another cycle. The rotary turntable 16 rotates 90° to transfer the pot 18 having an O-ring to the "bag and O-ring welding station". At the bag and O-ring welding station, a bag-like means is supplied. The bag-like means, as shown at 10 in Figure 1, are adhered to a backing paper and are spaced apart from one another. The bag-like means are adhered along the edge of their open end to the backing paper and are open at their right hand sides (according to the embodiment shown in Figure 1) so as to form an entrance to each bag-like means. An eight finger gripper assembly 19 (explained in detail below) is adapted to grip the open end of a bag-like means. Figures 3 and 4 illustrate the gripper assembly 19 with a bag-like means attached thereto. In order to arrive at this position, the gripper assembly 19 is pivoted into a position approximately 10° past the vertical. The backing paper with an attached bag-like means is indexed or moved into a curved trough. The curved trough bends the two plies of plastic film of the bag-like means so that the lower layer of film, that is adhered to the backing paper, is stretched about the perimeter of the curved trough. The upper layer of plastic film is puckered or rippled. The rippled separation between the two plies of plastic film opens the bag-like means. A high pressure blast of air is applied to the open end of the bag-like means to inflate the bag-like means and the gripper assembly 19 pivots forward approximately 10° to place the roller fingers just inside the mouth of the inflated bag-like means. A double acting twin rod cylinder (not shown) drives the actuator plate 43 downwardly and as described below. The roller fingers assume a circular shape and in so doing grip and stretch the mouth of the bag-like means causing the bag-like means to release from the backing paper. Bag-like means strip air jets direct high pressure gas or air to ensure that the nose or closed end of the bag-like means is also released from the backing paper. With the bag-like means still inflated, the gripper assembly 19 pivots forward and the nose of the bag-like means is guided into and slides down a pivoted curved guide chute 49 and into the pot 18 on the rotary turntable 16 with the O-ring positioned in the annular groove 17. During this movement of the gripper assembly 19, air is continuously supplied by an air jet 48. The force of the air jet 48 pivots with the gripper assembly 19 to keep the bag-like means inflated. The guide chute 49 then pivots back to make room for a weld head 51, shown in Figure 5, to move into position by pivoting from the side and then moving downwardly onto the top of the pot 18. The weld head 51 then presses down through the hole in the back of the gripper assembly 19 formed by the movement of the arms and fingers trapping the plastic film of the stretched bag-like means between a heated plate and the O-ring beneath. Welding of the plastic film to the O-ring is performed for a short time of about 0.3 seconds at a temperature of about 140°C + or -10°C. The bag-like means is located over the pot 18 such that the plastic film of the bag-like means overlaps and descends down the outside of the pot 18. Figure 6 illustrates the position of the elements during the welding procedure. The gripper assembly 19 is lowered still further. The further lowering of the gripper assembly 19 assists in stripping the annulus of excess film formed by the overlap of plastic film over the outer periphery of the O-ring and pot 18. The heat of the welding procedure causes weakness in the plastic film so that the gripper fingers can easily strip the surplus plastic film and a neat weld is formed without any surplus plastic film attached to the weld. The weld head 51 then lifts and pivots back to the side of the machine and the gripper assembly 19 begins to pivot back towards the rest position. At approximately 45° the gripper assembly 19 pauses and the curved guide chute 49 pivots forward to shield and protect the recently welded bag-like means in the rotary turntable 16. The double acting twin rod cylinder then lifts the actuator plate 43 causing the gripper fingers to contract and release the bag-like means. While this procedure is occurring, high velocity air jets cause the annulus of excess film to be blown away from the pot 18 and deposited to scrap. The gripper assembly 19 then completes the return to the initial position of about 10° past the vertical. The four position rotary turntable 16 then moves 90° to a spare station and then through a further 90° taking the newly formed bag-like means to a product removal station. At the product removal station, a vacuum through the annular groove 17 of the pot 18 is terminated. A product removal head 52 holds the welded product and pivots through a 180° arc. A vacuum is initiated through an annulus 53 on the product removal head 52, thus, enabling the product removal head 52 to pick the newly formed welded bag-like means from the rotary turntable 16. The welded bag-like means and removal head 52 rotate through a 180° arc so that the welded bag-like means can be inverted under a transfer tube. The welded bag-like means is then inflated and the vacuum through the annulus 53 to the product removal head 52 is terminated to cause the welded bag-like means to be launched up the transfer tube. The welded bag-like means is pushed by various air jets along the transfer tube 54 and into platens (not shown). The platens can be used to transfer the welded bag-like means to a testing station. Figures 8, 9, and 10 illustrate the gripper assembly 19 in detail. The gripper assembly 19 comprises two fixed finger rollers 20 and two sets of movable finger rollers 21, 22, 23, and 24 which are mounted on the ends of two sets of arms on each side of a center line running through the gripper assembly 19. Each set has arms 25, 26, and 27 with pins 30, 31, and 32 extending through slots 33, 34, and 35 in a cam plate 36. The lower ends of the arms are connected by further pins 37, 38, and 39 through slots 40, 41, and 42 through an actuator plate 43. The actuator plate 43 is movable between upper and lower positions as shown in the "split views" of the left and right hand sides, respectively, of Figure 8. The lower pin 24 is mounted on a rod which is directly connected to the actuator plate 43. Each of the gripper fingers have rollers 44 and these can be seen in Figure 9. Figure 9 illustrates the rollers 44 mounted on a fixed pin 45. The fixed pin 45 is mounted on the end of the respective arm and has an enlarged head 46. The enlarged head 46 serves to retain a roller sleeve 47. The roller sleeve 47 is rotatable on the pin 45. The roller sleeve 47 has an enlarged shoulder 48 at its outer end. In operation the gripper fingers move from a first position where they are all grouped together into a second position where they form a circular shape by caused the cam plate or actuator plate 43 moving downwardly. The invention includes a process for welding a reinforcing member to a bag-like means. The process involved placing a reinforcing member into an annular groove on an outer surface of at least one hollow mandrel. Then, opening an open end of the bag-like means with a means for opening having a gas injector means for injecting gas into the open end of the bag-like means is performed. Gripping the opened end of the bag-like means at a plurality of sites on a circumference of the open end of the bag-like means occurs. Extending the open end of the bag-like means and applying a closed end of the bag-like means into the hollow mandrel and the open end of the bag-like means over the hollow mandrel at the outer surface with an annular groove for holding the reinforcing member is performed. Welding the reinforcing member to the bag-like member follows. The process can further comprise ejecting the welded bag-like means from the mandrel. The process step of gripping can be performed by a plurality of prongs. The prongs are positionable within the open end of the bag-like means at individual sites on the circumference of the open end of the bag-like means. The step of extending the open end of the bag-like means can be performed by a cam member whereby operation of the cam member positions the prongs in one of two conditions. The two conditions are a first condition wherein the prongs are gathered together in a substantially linear position for insertion into the opened open end of the bag-like means. A second condition can be one wherein the prongs are separated from one another to extend the open end of said bag-like means.

Claims: Apparatus for welding a reinforcing member to a bag like member (10) comprising welding means and a hollow mandrel (18) adapted to receive in its interior a closed end of the bag like member (10) with the reinforcing member to be welded to the bag like member over the outer surface of the mandrel by said welding means characterised in that the outer surface of the mandrel has a groove (17) shaped to the form of the reinforcing member; means are provided for applying the closed end of the bag like member into the hollow mandrel and an open end of the bag like member over the hollow mandrel at the outer surface of the groove (17), the reinforcing member being located with respect to the bag like member at the position of the groove. Apparatus as claimed in claim 1 in which the means for applying the bag like member includes means (19) for gripping the bag like member at a plurality of sites on a circumference of the open end of the bag like member. Apparatus as claimed in claim 1 or claim 2 in which the means for applying the bag like member includes means (20, 21, 22, 23, 24) for expanding the open end of the bag like member. Apparatus as claimed in any one of the preceding claims in which the means for welding the reinforcing member includes means (51) for applying heat and/or pressure. Apparatus as claimed in any one of the preceding claims in which the reinforcing member is located in the groove (17) prior to the application of the bag like member. Apparatus as claimed in claim 2, 3, 4 or 5 in which the means for gripping the bag like member includes a plurality of prongs (20, 21, 22, 23, 24) positionable within the open end of the bag like member and cam means (30, 31 and 32) for moving the prongs from a closed position in which they enter the bag like means and a position in which they are separated from one another to expand the open end of the bag like member. Apparatus as claimed in claim 6, in which the gripper prongs are in the form of captively held rollers (44) rotatable on axes parallel to one another and to the bag like member. Apparatus as claimed in claim 6 or claim 7 in which the prongs (20, 21, 22, 23, 24) in the expanded condition provide an opening therein, and the welding means is in the form of a head (51) which can pass through the said opening. Apparatus as claimed in any one of the preceding claims including means (19) for removing surplus material at the open end of the bag like means extending beyond the reinforcing member. Apparatus as claimed in claim 9 in which the means for removing the surplus material is provided by movement of the prongs (19) after welding has taken place. Apparatus as claimed in any one of the preceding claims in which one or more gas injectors are provided to open and/or maintain open the open end of the bag like member. Apparatus as claimed in any one of the preceding claims in which the mandrel is mounted on a turntable (16) which rotates the mandrel to operationable positions, in which the bag like material is applied thereto, welded thereto and removed therefrom. Apparatus as claimed in any one of the preceding claims in which the bag like member and the reinforcing member are annular. Apparatus as claimed in any one of the preceding claims in which the reinforcing member welded to the bag like member is a contraceptive sheath. Apparatus as claimed in claim 14 in which the contraceptive sheath is for female use. A method for welding a reinforcing member to a bag like member (10) comprising the steps of applying into a hollow mandrel (18) having an outer surface a closed end of a bag like member (10) and an open end of the bag like member over the hollow mandrel (18) at the outer surface thereof and welding the reinforcing member to the open end of the bag like member characterised in that the outer surface of the hollow mandrel (18) has a groove (17) shaped to the form of the reinforcing member and the reinforcing member is located with respect to the bag like member at the position of the groove. A method as claimed in claim 16 in which the step of applying the bag like member (10) includes gripping the bag like member at a plurality of sites (20, 21, 22, 23, 24) on a circumference of the open end of the bag like member. A method as claimed in claim 16 or claim 17 in which the step of applying the bag like member includes means (20, 21, 22, 23, 24) for expanding the open end of the bag like member. A method as claimed in claim 16, 17 or 18 in which the step of welding the reinforcing member includes applying heat and/or pressure. A method as claimed in any one of claims 16 to 19 including a step of removing surplus material at the open end of the bag like means extending beyond the reinforcing member. A method as claimed in claim 20 in which the step of removing the surplus material is performed by movement of prongs (21, 22, 23, 24) after welding has taken place.

Inventors: KRUCZYNSKI ADAM, MILLER ANNE, KRUCZYNSKI, ADAM, MILLER, ANNE, MILLER, ANNE, THE TECHNOLOGY PARTNERSHIP
Applicants: CHARTEX INT PLC, CHARTEX INTERNATIONAL PLC
Application year: 1993
Main classification: B31B19
IPC codes: B29C65, A61F6, B29L22, B31B19