GB1588609A

GB1588609A - Process and moulding apparatus for the manufacture of sliding clasp fasteners

Info

Publication number: GB1588609A
Application number: GB2563676A
Authority: GB
Original assignee: Lightning Fasteners Ltd
Current assignee: Lightning Fasteners Ltd
Priority date: 1976-06-21
Filing date: 1976-06-21
Publication date: 1981-04-29
Also published as: ES459986A1; FR2355639B1; CH617124A5; DE2727839A1; FR2355639A1

Abstract

The aim of the process is to simplify the moulding device serving for carrying it out. The moulding device has a carrier (10) which is rotatable intermittently about a shaft (11) and bears on its circumference a row of sliding pieces (13) with mould cavities which can be pressed against a backing tape (T) for the purpose of moulding coupling elements to said backing tape (T). The outer surfaces (14) of a group of adjacent sliding pieces form a clamping surface in which a row of mould cavities (15) is formed. A pressing element (26) can be moved whilst the carrier is stationary in order to press the backing tape against the clamping surface. At least one of the sliding pieces can be moved relative to the carrier in order to obtain a region of the backing tape which is free of coupling elements. <IMAGE>

Description

(54) PROCESS AND MOULDING APPARATUS FOR THE MANUFACTURE OF SLIDING CLASP FASTENERS (71) We, LIGHTNING FASTENERS LIMITED, a British Company of Kynoch Works, Witton, Birmingham B6 7BA, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a process and moulding apparatus for the manufacture of sliding clasp fasteners having series of coupling elements moulded on to carrier tapes.

It has been proposed to mould series of coupling elements of a sliding clasp fastener on to carrier tapes located between parts of a flat mould and to move a slide transversely of the mould to bring appropriate mould cavities into position to form end components at the end of the series of coupling elements. However, special feed means are required to draw the tape through the mould whilst accurately controlling the longitudinal incremental feed of the tape to achieve a constant pitch spacing of the coupling elements.

It has also been proposed to provide a rotary mould in which each mould cavity is formed by separate and opposing mould parts which are moved towards one another transversely of the mould to complete a mould cavity and to engage with opposite faces of a carrier tape extending around part of the mould. The movement of the mould parts to complete each mould cavity requires complicated mechanism.

According to one aspect of the present invention, moulding apparatus for the manufacture of sliding clasp fasteners having series of coupling elements moulded on to carrier tapes includes a carrier intermittently rotatable about an axis and supporting a peripheral series of slides each having a surface which faces radially outwardly of the carrier, a clamping surface provided by the said surfaces of a group of adjacent slides, a series of coupling element mould cavities in the clamping surface for the moulding of coupling elements on to a carrier tape when it is clamped against the clamping surface, and a platen movable towards the carrier to clamp the carrier tape against the clamping surface during non-rotation of the carrier, rotation of the carrier and its slides causing the coupling element mould cavities to move sequentially past the platen along a peripheral path, a selected slide or slides being slideable relative to the carrier to displace the respective coupling element mould cavity or cavities from said path to provide a region of the carrier tape without any coupling element or elements, and the slide or slides being returnable to re-locate the coupling element mould cavity or cavities in said path.

The slides are preferably supported on the carrier by respective slideways which are directed transversely of the direction of rotation of the carrier. The apparatus preferably comprises an additional mould cavity locatable in the peripheral path for the formation of an end component adjacent an end of the series of coupling elements.

The additional mould cavity for forming the end component may be provided in an auxiliary slide arranged to displace at least one of the slides having a coupling element mould cavity, the auxiliary slide having a surface which faces radially outwardly to match that of the displaced slide or slides whereby movement of the auxiliary slide in one direction will locate the end component cavity in said peripheral path with the radially outwardly facing surface of the auxiliary slide forming part of the clamping surface, and movement of the auxiliary slide in the opposite direction will withdraw the end component cavity from said peripheral path.

Although location of the auxiliary slide may be effected manually, it is preferable to provide automatic mechanical or other means to effect such location. For example, transfer fingers may be provided for moving the auxiliary slide to displace the appropriate slide or slides and subsequently to return the displaced slide or slides. A stationary support for the auxiliary slide may be positioned adjacent the carrier whereby the auxiliary slide may be transferred in said one direction from the stationary support to the carrier for forming the end component, and may subsequently be returned in said opposite direction to the stationary support after the end component has been moulded.

Alternatively, the additional mould cavity for forming the end component is preferably provided in one of the slides so that displacement of this slide enables the respective end component mould cavity to be located in said peripheral path. Some of the slides may be equi-angularly spaced and provided with at least one of the additional mould cavities. Preferably each slide is provided with at least one of the additional mould cavities.

Apparatus of the present invention may be employed to manufacture sliding clasp fasteners having coupling elements moulded on only one face of a carrier tape. However, in the more usual forms of sliding clasp fasteners having series of moulded coupling elements, the elements are moulded astride an edge of a carrier tape, ie on both faces of the carrier tape. For moulding such fonns of fastener, apparatus of the present invention may further comprise complementary coupling element mould cavities in the platen for appropriate registration with the coupling element mould cavities in the series of slides whenever the platen clamps the carrier tape against the clamping surface.At least some of the complementary coupling element mould cavities in the platen may be parallely displaceable relative to the clamping surface in conjunction with the selected slide or slides to provide the region of the carrier tape without any coupling element.

Mthough this displacement may be achieved by moving the entire platen, a platen slide is preferably mounted in the platen for sliding movement parallel to the clamping surface and also for movement with the platen to clamp the carrier tape against the clamping surface, the platen slide defining the displaceable coupling element mould cavities. In the case where end components are to be provided, the platen or the platen slide may define an end component mould cavity for registration with the additional mould cavity in the slides.

The carrier and its peripheral series of slides are preferably arranged such that the surfaces of the slides are parts of a cylindrical surface coaxial with the carrier axis. Preferably, a support shoe is provided at the side of the carrier diametrically opposite to the platen for supporting the carrier against the pressure applied by the platen when clamped against the clamping surface.

A second series of coupling element mould cavities is preferably arranged in the clamping surface parallel to the first series of coupling element mould cavities, whereby rotation of the carrier and its series of slides will cause the second series of coupling element mould cavities to move sequentially past the platen along a second peripheral path parallel to the first peripheral path for moulding the second series of coupling elements on to a second carrier tape when it is also clamped against the clamping surface, and the selected slider or slides being slideable to displace the corresponding coupling element mould cavities of both series from said paths to provide a region on each carrier tape without any coupling element.An additional mould cavity may be locatable in the second peripheral path for the simultaneous formation of an end component adjacent an end of the second series of coupling elements.

According to a further aspect of the invention a process for the manufacture of sliding clasp fasteners having series of coupling elements moulded on to carrier tapes includes intermittently rotating a carrier supporting a peripheral series of slides of which the radially outwardly facing surfaces provide a clamping surface having a series of coupling element mould cavities whilst simultaneously feeding a carrier tape around part of the clamping surface, advancing a platen towards the carrier so as to clamp the carrier tape against the clamping surface whilst the carrier is stationary, then injecting molten thermoplastics material into the mould cavities so as to adhere to the carrier tape, subsequently retracting the platen from the clamping surface and rotating the carrier to move the carrier tape and the moulded-on coupling elements past the platen whilst at least some of the coupling elements are supported in mould cavities, periodically moving at least one of the slides relative to the carrier whilst the carrier tape is unclamped thereby displacing the respective coupling element mould cavities to provide a region of the carrier tape without any coupling element, and subsequently returning the displaced slide or slides to relocate the coupling element mould cavities.

Two embodiments of the invention will now be described by way of example only, with reference to the accompanying drawings in which: Figure 1 is a perspective view of an apparatus in accordance with a first embodiment with parts shown broken away for clarity; Figure 2 is an elevation of the concavely curved surface of a platen slide forming part of the apparatus shown in Figure 1; Figure 3 is a view similar to Figure 1 with some parts omitted and showing certain movable parts in their alternative positions; Figure 4 is a perspective view of an apparatus in accordance with a second embodiment with parts shown broken away; Figure 5 is an elevation of the concavely curved surface of a platenslide forming part of the apparatus shown in Figure 4; and Figure 6 is a view similar to Figure 4 with some parts omitted and showing certain movable parts in their alternative positions.

Referring to Figures 1 to 3 of the drawings, moulding apparatus of the first embodiment for the manufacture of sliding clasp fasteners having series of coupling elements moulded on to carrier tapes, includes a carrier in the form of a drum 10 intermittently rotatable about an axis 11. The periphery of the drum 10 defines transverse slideways 12 supporting a peripheral series of movable slides 13, the length of the slides being approximately half that of the drum. Radially outwardly facing surfaces 14 of the slides are contiguous one with another and form an endless cylindrical clamping surface, the surface 14 of each slide having two parallel series of coupling element mould cavities 15 for the moulding of parts of coupling elements of a sliding clasp fastener.The mould cavities of each series are interconnected by a small semicircular circumferential groove 16 for a purpose to be hereinafter described.

Adjacent one face of the drum 10, a stationary support in the form of an arcuate cage 17 is fixedly supported by suitable brackets (not shown) the arcuate form of the cage following the ends of a group of the slideways 12 and associated slides 13 extending circumferentially from the one o'clock position to the five o' clock position.

An auxiliary slide 18 is disposed in the cage 17 and has the same length and curvature as the series of slides 13. The auxiliary slide 18 is adapted to enter and move along any adjacent set of three of the slideways 12. The radially outer surface of the auxiliary slide 18 defines end component mould cavities 19,20 for the moulding of parts of top and bottom end components of a sliding clasp fastener, the cavities 19 being for parts of top stop components, and the cavities 20 being for parts of bottom end components of well-known openend or separable type fasteners in which two halves of a fastener are completely separable from one another.

The end component mould cavities 19,20 are spaced apart in a circumferential sense to provide a length of mould surface 21 devoid of mould cavities. The end component mould cavities 19,20 are located along the auxiliary slide 18 so that movement of the auxiliary slide into the drum 10 and its displacement of certain of the slides 13 transversely of the drum enables the end component mould cavities 19,20 to be located in the circumferential path of the coupling element mould cavities 15 in the remaining slides 13. The movement of the auxiliary slide 18 into the slideways of the drum 10 is effected by means of two feed fingers 22 mounted at one end in a plate 23 secured to and movable in the direction of arrow Z by a piston rod of a piston and cylinder device (not shown), the feed fingers 22 passing through holes 24 in a side wall of the cage 17.

Subsequent return of the displaced slides 13 and the removal of the auxiliary slide 18 from the drum 10 is effected by means of a plunger 25 operated by a piston and cylinder device (not shown).

A platen 26 at one side of the drum 10 is movable radially of the drum towards and away from adjacent slides 13 and has a concave surface 27 which conforms to the radially outer surface of the series of slides 13.

A runner channel 28, and two rows of coupling element mould cavities 15a which are complementary to the mould cavities 15, are formed in the concave surface 27, the channel stopping short of the upper edge of the platen, and from the runner channel 28 a sprue hole 29 extends through the platen to open into a conical recess 30 arranged for engagement with a nozzle of a plastics injection machine (not shown).

Below the sprue hole 29, a platen slide 31 is mounted from the platen for movement parallel to the series of slides 13 in the drum 10. The platen slide 31 is movable in one direction, ie to the right in Figure 1, by contact with the plate 23, and in the other direction, ie to the left in Figure 1, by a ram 32 actuated by a piston and cylinder device (not shown).

The platen slide 31 has a concave surface 33 forming a continuation of the concave surface 27 of the platen. Referring to Figure 2 of the drawings the surface 33 defines rows of coupling element mould cavities 34 at each side of a channel 35, the mould cavities 34 being complementary to the mould cavities 15 in the slides 13, and end component mould cavities 36,37 at each side of a channel 38 and complementary to the end component mould cavities 19,20 in the auxiliary slide 18.

A support shoe 39 is mounted for movement radially of the drum 10 at a position diametrically opposite the platen 26 to support the drum 10 and its slides 13 against pressure applied by the platen 26 when moved towards the slides.

An arcuate surface of the support shoe 39 facing the drum has a circumferentially extending channel (not shown) to avoid contact of the shoe with moulded components.

The operation of the various piston and cylinder devices referred to above may be controlled for example by a cam shaft, or by means of an endless link chain having appropriately spaced cams secured thereto to operate respective valves, the cam shaft or chain being geared to the rotation of the drum 10. The slides may, of course, be set manually, particularly when the required length of fastener is an aliquot part of the circumference of the mould surface. The various slides are accurately located in their transverse operative positions by means of depressions in the slides registering with springloaded balls or the like in the slideways.

Additionally, pins may be provided extending from the concave surface 27 of the platen 26 to register in holes formed in the slides 13.

In use, the moulding apparatus is mounted in a plastics injection machine so that normal closing of the machine will cause the platen 26 and the support shoe 39 to move towards the drum 10. The auxiliary slide 18 is disposed in the lower end portion of the cage 17 and the platen slide 31 is positioned with its channel 35 aligned with the channel 28 in the platen 26.

Two lengths of carrier tape T each having a beaded edge as well known in slide fasteners constructions are introduced in the direction of arrows X between the series of slides 13 and the platen 26 with the faces of the carrier tapes lying against the surfaces 14 of the slides 13 to be substantially parallel to the axis 11 and the beaded edges of the tapes T located in the circumferential grooves 16. The carrier tapes T continue circumferentially of the series of slides to emerge from between the slides and the support shoe 39 to be led to take-off rolls (not shown). The drum 10 is indexed about its axis 11 in the direction of arrow Y corresponding to the pitch of several slides 1 3 equivalent to the operative length of the platen 26.

During stationary periods of the drum 10, the platen 26 and the support shoe 39 are moved into contact with the tapes whilst plastics material is injected along the channels 28, 35 and thereby into the coupling element mould cavities 15,34, and thus around the beaded edges of the carrier tapes T. Indexing movement of the drum 10 is arranged to move the uppermost moulded components to immediately adjacent the lower edge of the platen slide 3 1 so that the plastics runner connecting the moulded components provides a stop for the lower end of the channel 35. If required the length of the rows of moulded components above the sprue hole 29 may be reduced by introducing an arcuate finger into the runner channel 28 to stop-off the channel.

When it is desired to mould end components on the carrier tapes, the plate 23 and its fingers 22 are actuated following an indexing moving of the drum to move the auxiliary slide 18 into slideways 12 of the drum to locate the end component mould cavities 19,20 in the circumferential path of the coupling element mould cavities 15, the coresponding slides 13 being displaced along their slideways 12 from beneath the carrier tapes, as shown in Figure 3. At the same time, the platen slide 31 is moved by the plate 23 across the platen 26 to locate the channel 38 in alignment with the channel 28 in the platen.Injected plastics material will then flow along the channels 28 and 38, the material from channel 38 passing into the end component mould cavities 19,20,36,37. After this latter injection of material and retraction of the platen 26 from the drum 10, the ram 32 is actuated to return the platen slide 31 to relocate channel 35 with channel 28. The auxiliary slide 18 remains in the drum until it reaches a position where it can be returned to the cage 17 by operation of the plunger 25 against the displaced slides 13, movement of these slides ejecting the auxiliary slide from the slideways 12 whereupon the auxiliary slide drops to the lower end portion of the cage in readiness for its next insertion into the drum.

Depending upon the size of the drum and the length of fastener to be produced, more than one auxiliary slide may be provided in the cage 17 to be employed in succession.

If end components are temporarily not required to be moulded, then the auxiliary slide 18 may be dispensed with, the platen slide 31 may have only coupling element mould cavities 34 and the appropriate number of slides 13 with the platen slide 31 are displaced to bring smooth surfaces thereof into the path of the plastics injection zone so that a predetermined length of the carrier tapes will be devoid of any moulded components.

Apparatus of the second embodiment, shown in Figures 4 to 6 of the drawings, includes a carrier in the form of a drum 40 rotatable about an axis 41. The periphery of the drum defines transverse slideways 42 supporting an annular series of movable slides 43.

Each slide 43 has a radially outer surface 44 which, at one transverse portion, defines end component mould cavities 45 to form parts of top stops of a sliding clasp fastener, and also coupling element mould cavities 46 to form part of coupling elements immediately adjacent the top stops. Each slide has a plain portion 47 devoid of mould cavities, and then another portionhaving two rows, considered in a circumferential sense, of coupling element mould cavities 48. Each surface 44 has a further portion which defines end component mould cavities 49 to form parts of bottom end components of open-end type fasteners.

A platen 50 has a runner channel 51, coupling element mould cavities 48a, sprue hole 52 and a platen slide 53. As shown in Figure 5 this platen slide 53 defines rows of coupling element mould cavities 56,57 at each side of channel 58. A support shoe 59 is mounted diametrically opposite the platen to support the drum, the shoe having a clearance channel (not shown) to avoid contact with moulded components. The slides 43 are moved by pushrods 60 and the platen slide 53 is moved by pushrods 61, each of these pushrods 60,61 being controlled independently by piston and cylinder devices (not shown) so that each slide may be moved in either direction along its respective slideway. Location means are provided to locate the slides in their transverse operative positions as described for the first embodiment.

In use, the slides 43 in the drum are normally located along their slideways 42 and the platen slide 53 is located across the platen so that molten plastics material will be injected from the sprue hole 52 into the coupling element mould cavities 48,54. When it is required to mould end components, separated by a gap space, the appropriate slides 43 in the drum 40, for example slides 43a, 43b and 43c, Figure 6, are moved to locate the respective mould cavities 45,46 plain portion 47, and mould cavities 49 in their moulding position, and the platen slide 53 is moved along the platen until the channel 58 is in alignment with the channel 51 in the platen. After moulding the end components, the platen slide 53 is returned to locate the channel 55 with the runner channel 51, and the displaced slides 43 move round with the drum 40 until they depart from the carrier tapes at say the 12 o'clock position subsequent to which they are returned to their nor renal positions as shown in Figure 4 before they reach the vicinity of the platen 50. The slides 43 are returned by further unshown plungers, or alternatively by deflector plates situated at the ends of the drum 40 to channel or funnel the slides into the drum.

In modifications of either of the above embodiments, the end component mould cavities employed for moulding components of openend type fasteners may be replaced by mould cavities suitable for moulding two-part permanent bottom end stops, ie bottom stop parts which can be inter-engaged by mounting a slider of a sliding clasp fastener over them in one direction and once engaged are not disengageable thus preventing subsequent removal of the slider. Such bottom end stops are disclosed for example in United Kingdom Patent 1 479 363.

Instead of providing a platen slide 31 or 53, the respective platen 26 or 50 may be formed with several rows of mould cavities, some rows including end component mould cavities, with an appropriate number of sprue holes and the entire platen be displaced parallel to the series of slides in the drum. Although the second embodiment shows that a set of end component mould cavities 45,49 is provided in every slide 43, such sets of end component mould cavities may only be provided in several equiangularly spaced slides, the equal spacing of these slides corresponding to predetermined increments in the length of fasteners to be produced. Similarly a single set of end component mould cavities could be provided in only one slide in the event that the machine was intended to manufacture fasteners of only one specific length.

An advantage of apparatus of the present invention is that the carrier tapes for the fastener are accurately fed by movement of the mould itself by virtue of some moulded components on the tapes being retained in the mould cavities for at least 180 of mould rotation and ancillary tape feed devices are unnecessary. Also the length of fastener produced can be altered at will.

WHAT WE CLAIM IS: 1. Moulding apparatus, for the manufacture of sliding clasp fasteners having series of coupling elements moulded on to carrier tapes, including a carrier intermittently rotatable about an axis and supporting a peripheral series of slides each having a surface which faces radially outwardly of the carrier, a clamping surface provided by the said surfaces of a group of adjacent slides, a series of coupling element mould cavities in the clamping surface for moulding a series of coupling elements on to a carrier tape when it is clamped against the clamping surface, and a platen movable towards the carrier to clamp the carrier tape against the clamping surface during non-rotation of the carrier, rotation of the carrier and its slides causing the series o coupling element mould cavities to move sequentially past the platen along a peripheral path, a selected slide or slides being slideable relative to the carrier to displace the respective coupling element mould cavity or cavities from said path to provide a region of the carrier tape without any coupling element or elements, and the slide or slides being returnable to relocate the coupling element mould cavity or cavities in said path.

2. Moulding apparatus, according to Claim 1, wherein the slides are supported on the carrier by respective slideways which are directed transversely of the direction of rotation of the carrier.

3. Moulding apparatus, according to Claim 1 or 2, including an additional mould cavity locatable in the peripheral path for the formation of an end component adjacent an end of the series of coupling elements.

4. Moulding apparatus, according to Claim 3, wherein the additional mould cavity for forming the end component is provided in an auxiliary slide arranged to displace at least one of the slides having a coupling element mould cavity, the auxiliary slide having a surface which faces radially outwardly to match that of the displaced slide or slides whereby movement of the auxiliary slide in one direction will locate the end component cavity in said peripheral path with the radially outwardly facing surface of the auxiliary slide forming part of the clamping surface, and movement of the auxiliary slide in the opposite direction will withdraw the end component cavity from said peripheral path.

5. Moulding apparatus, according to Claim 4 including transfer fingers for moving the auxiliary slide to displace the appropriate slide or slides and subsequently to return the displaced slide or slides.

6. Moulding apparatus, according to Claim 4 or Claim 5, including a stationary support for the auxiliary slide positioned adjacent the carrier whereby the auxiliary slide may be transferred in said one direction from the stationary support to the carrier for forming the end component, and may subsequently be retumed in said opposite direction to the stationary support after the end component has been moulded.

7. Moulding apparatus, according to Claim 3 wherein the additional mould cavity for forming the end component is provided in one of the slides so that displacement of this slide enables the respective end component mould cavity to be located in said peripheral path.

8. Moulding apparatus, according to Claim 7, wherein some of the slides are equi-angularly spaced and are each provided with at least one of the additional mould cavities.

9. Moulding apparatus, according to Claim 7, wherein each slide is provided with at least one of the additional mould cavities.

10. Moulding apparatus, according to any preceding claim, including complementary coupling element mould cavities in the platen

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. renal positions as shown in Figure 4 before they reach the vicinity of the platen 50. The slides 43 are returned by further unshown plungers, or alternatively by deflector plates situated at the ends of the drum 40 to channel or funnel the slides into the drum. In modifications of either of the above embodiments, the end component mould cavities employed for moulding components of openend type fasteners may be replaced by mould cavities suitable for moulding two-part permanent bottom end stops, ie bottom stop parts which can be inter-engaged by mounting a slider of a sliding clasp fastener over them in one direction and once engaged are not disengageable thus preventing subsequent removal of the slider. Such bottom end stops are disclosed for example in United Kingdom Patent 1 479 363. Instead of providing a platen slide 31 or 53, the respective platen 26 or 50 may be formed with several rows of mould cavities, some rows including end component mould cavities, with an appropriate number of sprue holes and the entire platen be displaced parallel to the series of slides in the drum. Although the second embodiment shows that a set of end component mould cavities 45,49 is provided in every slide 43, such sets of end component mould cavities may only be provided in several equiangularly spaced slides, the equal spacing of these slides corresponding to predetermined increments in the length of fasteners to be produced. Similarly a single set of end component mould cavities could be provided in only one slide in the event that the machine was intended to manufacture fasteners of only one specific length. An advantage of apparatus of the present invention is that the carrier tapes for the fastener are accurately fed by movement of the mould itself by virtue of some moulded components on the tapes being retained in the mould cavities for at least 180 of mould rotation and ancillary tape feed devices are unnecessary. Also the length of fastener produced can be altered at will. WHAT WE CLAIM IS:

1. Moulding apparatus, for the manufacture of sliding clasp fasteners having series of coupling elements moulded on to carrier tapes, including a carrier intermittently rotatable about an axis and supporting a peripheral series of slides each having a surface which faces radially outwardly of the carrier, a clamping surface provided by the said surfaces of a group of adjacent slides, a series of coupling element mould cavities in the clamping surface for moulding a series of coupling elements on to a carrier tape when it is clamped against the clamping surface, and a platen movable towards the carrier to clamp the carrier tape against the clamping surface during non-rotation of the carrier, rotation of the carrier and its slides causing the series o coupling element mould cavities to move sequentially past the platen along a peripheral path, a selected slide or slides being slideable relative to the carrier to displace the respective coupling element mould cavity or cavities from said path to provide a region of the carrier tape without any coupling element or elements, and the slide or slides being returnable to relocate the coupling element mould cavity or cavities in said path.

for appropriate registration with the coupling element mould cavities in the series of slides whenever the platen clamps the carrier tape against the clamping surface.

11. Moulding apparatus, according to Claim 10, wherein at least some of the complementary coupling element mould cavities in the platen are parallely displaceable relative to the clamping surface in conjunction with the selected slide or slides to provide the region of the carrier tape without any coupling element.

12. Moulding apparatus, according to Claim 11, including a platen slide mounted in the platen for sliding movement parallel to the clamping surface and also for movement with the platen to clamp the carrier tape against the clamping surface, the platen slide defining the displaceable coupling element mould cavities.

13. Moulding apparatus, according to Claim 3 and Claim 11 or 12, wherein the platen or the platen slide defines an end component mould cavity for registration with the additional mould cavity.

14. Moulding apparatus, according to any preceding claim, wherein the carrier and its peripheral series of slides are arranged such that the surfaces of the slides are parts of a cylindrical surface coaxial with the carrier axis.

15. Moulding apparatus, according to any preceding claim, including a support shoe at the side of the carrier diametrically opposite to the platen for supporting the carrier against the pressure applied by the platen when clamped against the clamping surface.

16. Moulding apparatus, according to any preceding clam, including a second series of coupling element mould cavities arranged in the clamping surface parallel to the first series of coupling element mould cavities, whereby rotation of the carrier and its series of slides will cause the second series of coupling element mould cavities to move sequentially past the platen along a second peripheral path parallel to the first peripheral path for moudling the second series of coupling elements on to a second carrier tape when it is also clamped against the clamping surface, and the selected slide or slides being slideable to displace the corresponding coupling element mould cavities of both series from said paths to provide a region on each carrier tape without any coupling element.

17. Moulding apparatus, according to Claims 3 and 16, including an additional mould cavity locatable in the second peripheral path for the simultaneous formation of an end component adjacent an end of the second series of coupling elements.

18. Moulding apparatus, for the manufacture of sliding clasp fasteners having series of coupling elements moulded on to carrier tapes, constructed and arranged substantially as described herein with reference to and as shown in Figures 1 to 3 of the accompanying drawings.

19. Moulding apparatus, for the manufacture of sliding clasp fasteners having series of coupling elements moulded on to carrier tapes, constructed and arranged substantially as described herein with reference to and as shown in Figures 4 to 6 of the accompanying drawings.

20. Process for the manufacture of sliding clasp fasteners having series of coupling elements moulded on to carrier tapes, including intermittently rotating a carrier supporting a peripheral series of slides of which the radially outwardly facing surfaces provide a clamping surface having a series of coupling element mould cavities whilst simultaneously feeding a carrier tape around part of the clamping surface, advancing a platen towards the carrier so as to clamp the carrier tape against the clamping surface whilst the carrier is stationary, then injecting molten thermoplastics material into the mould cavities so as to adhere to the carrier tape, subsequently retracting the platen from the clamping surface and rotating the carrier to move the carrier tape and the moulded-on coupling elements past the platen whilst at least some of the coupling elements are supported in mould cavities, periodically moving at least one of the slides relative to the carrier whilst the carrier tape is unclamped thereby displacing the respective coupling element mould cavities to provide a region of the carrier tape without any coupling element, and subsequently returning the displaced slide or slides to relocate the coupling element mould cavities.

21. Process for the manufacture of sliding clasp fasteners having series of coupling elements moulded on to carrier tapes substantially as described herein with reference to Figures 1 to 3 of the accompanying drawings.

22. Process for the manufacture of sliding clasp fasteners having series of coupling elements moulded on to carrier tapes substantially as described herein with reference to Figures 4 to 6 of the accompanying drawings.