A press-on and split-off type fastener and a method and device for its manufacture

This Invention relates to a press-on and split-off type fastener.

A metal fastening strap disclosed in Canadian Patent specification No. 794,559 has a plurality of fastening catches spaced along the length of the overiapplng ends. The strap is overlaid on another in such a manner that the catch of each of the straps is exactly put on the opposite catch and the overlaid straps are pressed to engage the catches with each other and thereby prevent them from separating from each other by the stiffness of the metal body.

A fastener disclosed in French Patent specification No. 1,313,692 is made of a thermoplastic substance by molding and has ribs and grooves which are formed in the same shape as each other along the length of fastener strap. This fastener must be closed beginning at one end and working toward the other, much in the manner of closing a zip-fastener because it lacks resiliency.

A pouch having interlocking members made of thermoplastic substance is disclosed in US Patent specification No. 3,325,084. The interlocking member, however, has the same construction 7, as the fastener of said French Patent No. 1,313,692.

Another fastening device is described in German Utility Model No. 68 00 798 which relates to a device for fixing curtains, wall doth?and so on. The fastening of the object is accomplished by fixing to, for example, a wall, one of a pair of straps having a plurality of straight ribs and grooves having no phase difference, which are made of thermoplastic substance by molding, and by engaging It with the other strap which is sewed on a curtain. It can be said that the device ¾

56978/2 is the same as the fastener of said French Fatent in principle. However, it is a feature of the device that the ribs and grooves are formed in such a manner that it is not easy to separate the two straps once coupled.

The fasteners described in the above-;vnentioned specif!cations are disadvantageous in that they lack flexibility, that their component members can engage with each other only in face-to-face relationship and that they require complicated and expensive manufacturing processes. The fasteners of French Patent No. 1,315,692, US Patent 3,325,084 and German UM 68 00 798 have the further disadvantage that they allow easy separation of closure when subjected to a force in the transverse direction since there is no difference in the phase of the ridges.

Besides, a press-on andsplit-off type fastener consisting of a first tape having flexible hooks planted densely thereon and a second tape having loops planted densely thereon for engagement with the said first tap?, which fastener closes when the two tapes are placed face to face on the sides planted with hooks and loops pressed against each other and splits off when the tapes are forced away from each other, is also known. In the aforementioned conventional fasteners, one side of both the first and the second tapes has a piley woven construction« For the formation of hooks, therefore, the first tape requires the operation of cutting the material into the shape of hooks. Accordingly, this fastener has a drawback in that production efficiency cannot be Improved and the cost inevitably proves relatively high. When two second tapes are placed face to face on the sides densely planted with loops and pressed against each other, they produce no closure. When two first tapes are

36978/2

C* placed face to face on the eidee densely planted with hooks and pressed against each other, there is closure

U, . * . ¹ of very weak strength. Therefore, it is requisite that tie first and second tapes should he used in pairs.

According to the present invention therefore, there is provided a press-on and split-off type fastener member formed of a synthetic resin, and comprising a plurality of elongate corrugated strips arranged in parallel to each other when viewed perpendicularly to the plane of the fastener member and joined to each other along lateral edges thereof, each of said corrugated strips comprising a series of alternate ridges and grooves, the strips being so staggered in their longitudinal direction that the ridges of each strip are adjacent the grooves of the adjoining strips, the arrangement being such that when a first fastener member is laid, over a second fastener member, and the first and second members pressed together, the ridges of the strips in each of said members enter the grooves of the other member and are retained therein by ffictional engagement with the lateral edges of the ridges of the ridges of adjoining strips.

Hereinafter a fastener member will occasionally be called a fastener.

The present fastener is flexible and can easily be produced by pressing synthetic resin sheet. It is possible to close the fastener elements by pressing either side of one against either side of the other. The engaging force of the fastener is very strong since it has strong resistance not only against longitudinal forces but also aglnst transverse forces. This is because the fastener ridges and grooves have a phase-difference throughout.

56978/2

The invention also relates to a method of manufacturing a press-on and split-off type fastener according to the invention, wherein a sheet of synthetic resin is passed between a group of rolls arranged in opposing pairs» each of the said rolls being formed of a plurality of .?discs of a fixed width arranged face to face, each of the said discs having curved ridges and grooves of the same form in a continuous manner and the said ridges and grooves in any two adjoining discs being staggered in position in a fisted relationship*

The Invention further relates to a device for manufacturlng a press-on and split-off typo fastener member according to the Invention, comprising a group of roihls and means for passing a sheet of synthetic resin between said, group of rolls, said rolls being arranged opposite to one another, each of the said rolls being formed of a plurality of discs of a fixed width arranged laterally, each of the said discs having curved ridges and grooves of the sane form in a continuous manner, the said ridges and grooves in any two adjoining discs being staggered in position in a fixed relationship.

The invention will be further explained with reference to the schematical drawings in which

Fig. 1 is a diagram illustrating the state in which the conventional press-on and split-off type fastener is used;

Fig. 2 is a front view of one typical embodiment of the fastener according to the present indentionI

Fig. ל is a side view thereof;

Pig. 4 and Fig. 5 are enlarged sectional views along lines IV-IV and V-V indicated in Fig. 5 respectively;

369.73/2

Fig. 6 is a diagram illustrating the state of cl&sure;

Fig. 7 is an enlarged sectional view along line VII-VII indicated in Fig. 6;

Fig. 8 is a front view of another embodiment} i

Fig. 9 and Fig. 10 are sectional views of the state of closure;

Fig. 11 and Fig. 12 are sectional views of a modified ' fastener in the state of closure;

Fig. 13 is a side view of another typical embodiment of the fastener according to this invention;

Fig. 14 is a diagram illustrating the fastener of Fig. 13 in the state of closure;

Fig. 15 is a front view of another typical embodiment of the fastener according to this invention;

Fig. 16 is a aide view thereof;

Fig, 17 is an enlarged sectional view along line XVII-XVII indicated in Fig. 16;

Fig. 18 is a front view of another embodiment of the fastener according to this invention;

Fig. 19 is a side view thereof;

Fig. 20 is a side view of the state of closure;

Fig. 21 is an enlarged side view along line XXI-XXI Indicated in Fig. 20;

Fig. 22 is a side view illustrating another embodiment in the state of closure;

Fig. 23 is a front view of another embodiment of the fastener according to this invention;

Fig, 24 is a sectional view illustrating an example of the state of closure of the fastener shown in Fig. 23;

36978/2

Pig. 25 18 an outline diagram illustrating a device for manufacturing the fastener?

Fig. 26 Is a front view of a roll of the first group of rolls?

Fig. 27 Is,a longitudinal section of the roll?

^! ! Fig, 28 is an enlarged perspective view of a disc.

Fig. 29 Is an. enlarged sectional view of part of the rolls in the state of engagement;

Fig, 30 1b an enlarged sectional view of a fastener passing between a group of rolls;

Fig. 31 is an enlarged perspective view of part of ta roll of the second group of rolls?

Fig, 32 is a sectional view illustrating the formation of projeotions;

Fig, 33 is an enlarged sectional view of a fastener having projection?

Fig. 34 is an enlarged perspective view of part of another embodiment of a roll used in a fastener manufacturing device?

Fig. ?5 is a side view of a longitudinal section of a fastener formed by the use of the roll illustrated in Fig. 34?

Fig. 36 is an enlarged perspective view of part of a roll of another embodiment;

Fig. 37 is a side view of a longitudinal section of a < fastener formedpccording to Fig. 36;

Fig. 38 is an enlarged perspective view of part of a roll of another embodiment;

Fig, 39 is a side view of a longitudinal section of a fastener formed according to Fig. 38? and ’ Fig. 40 is an enlarged perspective view of a fastear of another embodiment.

3697Θ/2

Figure 1 shows a belt which is formed of the second tape of a conventional*^ress-on and split-off type fastener. To obtain desired closure on the side of the said second tape 1 having loops planted densely as shown in Fig. 1, the first tap® 4 oust be fixed at one end of the belt, with its back 3 against the side of the second tape opposite to the side having loops planted densely 80 that the side 5 densely planted with hooks and the side 2 densely planted with loops face in opposite directions from each other. Otherwise, the belt fails to function as required. According to the present Invention, however, the fastener can be used as a belt by itself without the use of what corresponds to the first tape.

As a matter of course, the fastener of the present invention closes when two fastener component tapes of an identical construction are placed fade to face and pressed against each other and it can be used for purposes similar to those of the conventional presa-on and split-off type fastener.

As is clear from Fig. 2 to Fig. 5 inol., the fastener A of this Invention has a plurality of corrugated stripe joined in an orderly arrangement in parallel, each strip having a fixed width and incorporating curved ridges 11 and grooves 12 of approximately similar shapes alternately in a continuous manner, and any two adjacent corrugated strips» a^ and a₂, are placed so that the ridges (or grooves) of one strip a, stand Immediately next to the grooves (or ridges) of the other strip a₂. These strips are formed of a synthetic resin.

Accordingly, where the two adjacent corrugated strips and a₂ are so related with each other that the ridges(grooves) of one strip 8_ד or a₂ are aligned with the grooves (ridges)

36978/2 of the other etrip a₂ or a^, the corrugated strips and a₂ cross one another in a series of X'g. The ׳ two strips join at such cross points which fall at the middle of the height from grooves 12 to ridges 11 and are in Orderly arrangement in parallel. And, the ridges (groove־) of the ־trip and the gr־־ve־(rldg־־) of the strip a₂» when looked at from the side, i,e. perpendicular to the direction in which they are in orderly arrangement, form a series of hollow spaces 13.

Each of the aforementioned hollow spaces 13 has a circular shape if the ridge 11 and the groove 12 each have a semicircular form. If the ridge and the groove each have a hyperbolic form, the hollow space has a more or less elliptic shape, '

The fastener member A of the present invention has ridges and grooves on both sides thereof, furthermore, the ridges and the grooves in any two adjoining corrugated strips and a₂, are staggered in position in a fixed relationship. With respect <ιφ one corrugated strip a₂, for example, a groove 12 occurs in each interval between ridges 11 and 11 ( of the adjoining corrugated strips a^ and a^) and, at the same time, a ridge 11 odours in each interval between grooves 12 and 12. In the group of corrugated strips that are in orderly arrangement in parallel, each individual strip is joined with its adjoining strip Only, at points where they cross each other, the said points falling along straight lines running in the direction of the fastener's width. Therefore, the fastener can be bent at right angles to the long axis of the band without having to deform the ridges

36978/2 and grooves. Thus, the fastener enjoys sufficient flexibility,

When one fastener member is bent in an endless form to permit opposite sides of that fastener member 10 be placed face to face, when one fastener member is folded back to permit one same side of that fastener member to be placed face to face or when two fastener members are placed one on top of the other as Illustrated in Fig. 6 and Fig, ך so that 1 1 11 grooves 12 of one fastener member A fall over fidges 11 of the other fastener member A¹¹, the ridges of the said fastener member A^ advance over ridges 11^ of the other fastener member A^ and come to rest on grooves 12^ and ridges

X 1 °ome of the fastener member A similarly/to rest on goove 12^xxof the fastener member A^¹.

For practical purpose, it is sufficient for the corrugated f strip to measure 1 mm in width, 0.5 mm in thickness, 2.5 mm in height from the top of ridge 11 to the base of groove 12, and about 5 mm in distance between adjoining ridges and between adjoining grooves. Therefore, relationships ’⁷that permit ridges of one fastener member to enter between ridges of the other fastener member and come to rest on grooves intervening between them occur numerously in a small area, whereby the two fastener members A־*־ and A^ ^are °l°^sed with sufficient force by mere engagement and friction.

When a force is exerted so as 10 move fastener members in the direction of width from their closed state, since ridges of one fastener member are engaged with grooves intervening between ridges of the other fastener member they will not be moved at all. When a force is exerted so as to move one fastener member over the other fastener member in the direction

36978/2 of the length, of the corrugated strips, it cannot be moved.

11־ ו

Another fastener member A of the same construction can further be fastened onto either of the two fastener members which are in the closed state as mentioned above when it is placed on top and pressed down.

Therefore, it is evident that two fastener members which are in the closed state can be separated by merely pulling them apart with a force which overcomes the force with which the closed sides are held in engagement by friction. Ths relative position of one fastener to the other in the closed state can be varied in fine degrees by allowing the ridges on one band to come to rest in the next set of grooves on the other band.

between

Since the distance/adjoining grooves in a given corrugated strip can be fixed in the neighborhood of 2.5 mm as already mentioned, the position of the closed state can be varied very finely from the practical point of view.

Where two fastener members are used in a situation where the force of friction by contact alone proves Insufficient for the desired closure, the difficulty is eliminated by the use Of the modified fastener of this invention illustrated in Fig. 8 and subsequent figures.

Referring to Fig. 8, a fastener member B has a projection 14 provided in the shape of a grain on both sides of each ridge and/or groove in the corrugated strip. From the practical point of view, since the fastener member is formed of thermoplastic synthetic resin as previously mentioned, the projection 14, through slightly protruding from the side, is compressed by the ridge of the other fastener which forces ?its way tfeibugh ridges to coms to rest on a groove intervening therebetween and con- 11 36978/2 sequently permits the passage of that ridge. After passage

Of the ridge, the projection returns tb its original form.

The group of projections 14 which have returned to \ their original form serve 10 hold the fidges of the other fastener member down from behind against the grooves of the fastener member to which they belong. Thus, they enable the fastener members to be retained in the closed state without relying solely upon the force of friction by contact.

To separate the two fastener members thus held in the closed state, there is required a strong force which compresses the group of projections 14 to permit the ridges of one fastener member to be withdrawn from those of the other fastener member in addition to overcoming the force of friction by contact.

The fastener member to be closed on the fastener member 2 is another fastener member 3\ as illustrated in Fig. 9 or it may be fastener member A of the aforementioned embodiment as Illustrated in Fig. 10.

As concerns the position of projections 14, it suffices for the purpose to place them on both lateral edges at the peak point of the ridges in the case where tie reverse side of the ridges of one fastener member is adjacent to the reverse side of ridges of the other fastener member, such that the ridges of the first fastener member are placed soas to come to rest on the grooves of the second fastener member as Illustrated th Fig. 9. In the case of Fig. 10 wherein voids are formed between the reverse faces of the ridges of the two fastener members, such projections may be placed on both lateral edges of the base of the grooves.

36978/2

The aforementioned projection 14 may be formed in the ehape of a horn of a hook as shown in Fig. 11 and Fig. 12. Consequently, ridges of the other fastener members, while in the process of coming to rest on grooves, bend such horns or hooks 15 to gain passage therethrough. After their passage, the horns or hooks 15 return to their original dape by virtue of the elasiticity of the resin and get caught on the ridges of the other fastener from behind, producing a practically inseparable closure.

Fig. 13 shows a fastener member having component strips formed by repeating only the ridges or grooves, namely, by elimirefcing either ridges or grooves from the corrugated strips of the fastener of Fig. 2 to Fig. 7, incl.

To be more specific, this is a fastener which has a plurality of corrugated strips adjoined and in orderly arranged ment in parallel, each of the said strips having curved ridges (or grooves) 21 of the same&rm In a continuous manner. The said wave-formed strips, made of thermoplastic synthetic resin, are placed in such a positional relationshiptthat the peak point of the ridges in one strip are aligned with the points where the ridges in the other strip are Joined.

Therefore, the fastener member which is formed in thia way has ridges 21 on only one side, dverse or reverse, thereof because of the group of wave-formed strips, while it has recesses 22 conforming to the sMd ridges on the remaining side. By having ridges on one side of one component tape placed in alignment with recesses 22 on the other side of the other component tape, closure can be obtained by the same principle as that of the fastener of Fig. 2 to Fig. 7, indl.

36978/2

<img file="IL36978A_D0001.tif" />

While this fastener is inferior to the:faetaer of Fig. 2 to Fig. 7, incl., in that no closure can be obtained by placing two sides which have ridges or recesses alone, it is easier to manufacture.

The fasteners of the embodiments shown in Figi 15 through Fig. 24 have a plurality of corrugated strips a of a fixed width ,adjoined and in orderly arrangement, eabh of the said strips having curved ridges 31 and linear flat portions 32 alternately in a continuous manner. The said corrugated strips, made of plastics, are placed in such a positional relationship that the ridges (flat portions) in one strip a^ are aligned with the points where the flat portions (ridges) of the adjoining strip a₂ are joined.

The flat portions are placed in the spaces at the lower end of ridges. In case ttie length of the flat portions is equal to that of the lower end of the ridges, the corrugated strips a. and a₉ are adjoined and in orderly arrangement in parallel at the lower end of the ridges and at the end of the flat portions.

However, in case the length of the flat, portions is slightly shorter than that of the space at the lower end of the ridges, namely, if the length 1 of the flat portions is shorter than the length I! of the space at the lower end of the ridges as shown in Fig, 18 and Fig. 19 the two corrugated strips a₁ and a₉ are adjoined at the aide at the middle of the height up to which the said strips tend to rise to make the ridges. In either case, when looked at from the direction of thickness crossing atta right angle to the direction of the corrugated arrangement, the plane composed of the flat poitims

36978/2 forms a series of hollow spaces 33 raised by the ridges. If the ridges are semicircular, the series of spaces are formed semicircular. If the ridges are hyperbolic, the series of spaces are firmed semi-elliptical.

Oonsequerily, fastener A of the aforementioned embodiment has ridges rising on the front surface with a group of corrugated strips arranged inparallel and ridges sinking on the back surface, the two kinds of ridges being arranged alternately. Furthermore, the ridges and the flat portions in any two adjoining corrugated strips and are staggered in position in a fixed relationship. With respect to one corrugated strip a_, for example, a flat portion 32 occurs JL in the space between ridges 31 and 31 of the adjoining oorrugat ed strips a₂ and a₂. As for the corrugated strip a₁ also, each flat portion 32 is located in the space between ridges 31 and 31 and each ridge 31 1b located in the space between flat portions 32 and 32; so that each of the flat portions is surrounded on four sides by ridges, while each of the ridges is surrounded on four sides by flat portions.

are

And, in the group of corrugated strips that/in orderly arrangement in parallel, each individual strip is joined with its adjoining strip at the ends of the flat portions of the latter or at points !slightly above the ridges where they cross each other, the said joining points falling in straight lines running in the direction of the fastener's width. Therefore, the fastener can be bent along such joined points without having to deform the ridges and flat portions.Thus the fastener enjoys sufficient flexibility.

When two fasteners of the same construction are placed one on top of the other as illustrated in ^ig. 20 and Fig. 21

36978/2 that ridges 31' of one fastener A* fall over flat portions 32 of the other fastener A, the ridges 31' of the said fastener A' advance along the spaces between the ridges 31 of the other fastener A and the tops of said ridges 31* come into contact with flat portions 32 of the other fastener, while at the same time the ridges 31 of the fastener A also advance along the spaces between the ridges 31' of the fastener A* and the tops of said ridges 31 come into contact with flat portions 32'. Thus the ridges 31' of the fastener A' engage with the side edges of the ridges 31 of the fastener A and the ridges with of the fastener A engage/the side edges of the ridges 31' of the fastener A' each by friction.

Again, of two fasteners of the same construction, if the front face of the other fastener A is placed on the back face of one fastenar A. as illustrated in Fig. 22 so that the ridges 31 of the fastener A fall over the hollow spaces formed by the ridges 31' of th® fastener A', the ridges 31 of the fastener A advance from the spaces between the flat portions 32' of the fastener A' to the hollow spaces 33’, namely, the back side of the ridges 31', to come to rest on the said hollow spaces 33', the sides of the ridges 31 engaging with the side edges of the flat portions 32' by fiction. In this case, it pis possible to engage the said engaged fastener A with another fastener by applying the back face of the former to the front face of. the latter, so that any number of fasteners can be engaged one on top of another in a series. It is also possible to bend one fastaer in an endless form and have both ends of the fastener engaged by placing their opposite sides face to face, thus making it a loop.

The fastener of the above-described construction is closed

36978/2 with the force of engagement at the side edges of the ridges or fMt portions of another fastener. Where two fasteners are used in a situation where the said force of engagement alone proves insufficient for the desired closure, the difficulty is eliminated by the use of the modified fastener of the embodiment illustrated in Fig. 23 and Fig. 24.

Fastener B has projections 34 on both sides of the top of each ridge. The said jrojections 34 extend slightly beyond both sides of each rd|ge. In the course of closing, the pr&amp;jections are compressed when they pass through the ״spaces between ridges or flat portions of another fastener, thus permitting the passage of the ridges of said other fastener. After passage of the ridges, they resume their former shape.

Then, the projections 34 serve to press down the projections at the passed or the upper face of the passed flat portions. The projections thus apply a force, in addition to the force of contact and friction, to :hold the fastener in a closed state. To open the fastener, therefore, there is required a large amount of force which must not merely overcome the force of contact and friction but also compressively deform the group of projections 34 so as to enable the ridges of the first fastener to be pulled out of the ridges of the sedond fastener.

.The fastener to be closed on the fastener B may be a fastener B' identical to the fastener B as illustrated in F!g.

the lor it may be a fastener not provided with/said projections.

The projections ?4 may be formed in the shape of hooks inclining toward the flat portions.32 as illustrated in Fig. 24 7 % 36978/2 ⁷ or they may be shaped as square or round grains, If the outer faces of the ridges, especially their tops, are arched, the ridges of one fastener can pass more easily through the spaces between the ridges or flat portions of another fastener and the force of engagement in a closed state remains undecreased.

A device designed to manufacture a fastener of the kind mentioned above is now described by referring to Fig. 25 through F!g, 40, a soft thin resin sheet emerging from a plastics extruder 41 is passed between a series of rolls 43 formed of rolls 42 disposed in vertically opposite pairs. This sheet is mads of thermoplastic or thermosetting plastics or of synthetic paper. It may be available in the shape of a roll of long tape or of a wide roll of long film. Hereinafter these materials will be referred to collectively as sheet.

Each roll of the said series of rolls is of the type so as that provides forced rotation/to advance the sheet being passed. Each c omprises a fas־taer-f orming section 45 having a plurality of discs 44 joined face to face laterally and a pair of supporting rolls 46 and 46 each joined to the outermost disc 44 of the said fastener-forming section 45» )Between the two supporting roils 46 and 46, a supporting shaft 47 is disposed so as to pass through the discs 44, whereby the discs are immobilized collectively in a series. Each disc 44 has the same width as the corrugated strip a., or a₉ and has a corrugated circunference 48.

The said corrugated circumference 48 has the same shape as that of the corrugated strip a of the fastener to be produced. Any two adjoining discs are arranged In such relationship that the ridges (grooves) of one disc stand immediately

36978/2 next to the grooves(ridges) of the other disc.

Since any two adjoining discs are so disposed that the top of the ridges of one disc is aligned with the base of the grooves of the adjoining disc, the corrugations of every other disc are in perfect alignment.

The corrugations may be formed by joining the said discs face tp face or by cutting corrugations on the surface of a cylindrical roll. In the case of a roll formed by joining a number of discs, it becomes possible to vary the width of the fastener-forming section freely by changing the number of discs used in that roll!.

Rolls of the.above mentioned construction are placed one after another at short intervals to comps®®.the group of trolls 43»

The said roll is opposed across a small space to another roll of the same construction In such relationship that the ridges (grooves) of the waves of the former roll come into engagement with the grooves (ridges) of the waves of the latter roll. When the soft sheet emerging from. the extruder 41 is sent through the space formed between the opposite roll surfaces this sheet is pressed at the fastener-forming section 43 of the opposite rolls, whereby corrugations are formed in strips upon the surface of sheet. When the sheet has passed through the spaceeoformed between several pairs of opposite rolls, the said strips of corrugations are stabilized and, with gradual loss of heat, give a complete shape to a fastener tape. This fastener tape is then fed into the space formed between a card, clothing roll 49 having a surface planted densely with pins and a presser roll 50 held in slight contact with the said roll 49 in such manner that the corrugations

36978/2 formed on the sheet are not deformed. The description givent to this poiht covers only a fastener of the type that closes by virtue of the force of contact and friction between ridges and grooves.

A device for manufacturing a fastener having projections illustrated in Fig. 8 through Fig. 12 is obtained by introducing a minor modification to the aforementioned device. This device is illustrated in Fig. 28 through Fig. 30.

In thia device, small notches 51 and 51 are formed laterally at the top of ridges in the corrugations of eaoh disc 44 composing a roll 42. When a soft sheet 18 passed through a series of such rolls, basic projections 15’ and 15’ are formed on the lower plane of ridges 11 and on the upper plane of grooyes 12 in each strip of corrugations as illustrated in Fig. 30*

In this case, if the space across which the pair of rolls are opposed is increased slightly. the corrugated strips formed on the sheet under the pressure exerted by the edges of the corrugations of the rolls are allowed to acquire arched surfaces, which facilitate the insertion of the ridges of the manufactured sheet ״into the grooves of the next sheet at the. time of fastener closure.

Since the basic projections 15’ are formed alternately on the lower plane of ridges and the upper plane of grooves on the sheet, they are made to stick out of the lateral planes by allowing the sheet being discharged by the card clothing roll 49 and the presser roll 50 to pass through the second group of 5rolls 61.

Similarly to the roll 42 each of the second group of roils 62 has a multiplicity of discs 63 as shown in Figures 31, 32

36978/2 joined face to face laterally, said discs each having a corrugated portion 64 formed on the periphery thereof. Thus the rolls 62 receive the corrugated strips of the sheet on the outer surface of the corrugated portions 64, The corrugated portion 64 is slightly thinner than the disc 63 as shown in Fig. 31 and has raised portions formed at the top of ridges by making notches close to the top thereof. In receiving the corrugated strips of the sheet, the corrugated portion 63 supports the basal edges of the basic projections 15’ in direct contact with the lower plane of ridges. When the sheet in this state is beaten ^lightly on the outer surface by means of a »vibrator the basic projections 15’ are deformed and forced to stick out of the wave-formed strips, giving rise to projections 15 which serve to secure engagement at the time of fastener closure.

The basic projections 15 which are positioned at the grooves when the basic projections 15' are lightly beaten by a vibrator 66' and converted into outwardly raised projections 15’ when the sheet is reversed and received on the surface of the roll 62’ which is situated next to the troll 62.

After the basic projections at the ridges and the grooves have been caused to stick outward as mentioned above, the sheet is advanced through the space between a card clothing roll 67 planted densely with pins and a presser roll 68 held in slight contact with the said roll 67 so that the formed strips of corrugations will not be deformed.

The fastener manufactured as mentioned above has outwardly pointing projections at the ridges and the grooves of

36978/2 each corrugated atrip. Once the tape is closed, therefore, theprojections serve to keep the ridges of a first fastener tape held fast against the grooves of a second fastener tape, keeping the fastener in a state of firm closure. The embodiment illustrated in fig.' 34 and fig. 35 represents a further improvement of the fastener to be manufactured as mentioned above. At the top of ridges in the corrugations 48 formed on the periphery of discs 63 contained in each roll of the first group of rolls 43 arched projections 51’ are formed between opposite notches 51 and 51.

When corrugations are formed upon the sheet by using such a roll, the projection 51' gives rise to narrow indentationa on the inner side at the top of ridges and grooves along corrugations. As this sheet is forwarded to the second group of rolls 61j the outer side of the sheet opposite the said narrow indentations comes into contact with the raised A portions 65 of the diac 63. When the sheet is beaten by the vibrator, only the basic projections are exposed to the beating adtion and consequently caused to stick out side ways, giving rise to projections. The top ends of corrugations of the sheet are thin in wall thickness and:, therefore:» are not expanded wsideways by the beating. Consequently» only the bs^lc projections are caused to stick out and function to provide firm closure. If the top ends of corrugations are devoid of such thin-walled portions and if the sheet is beaten by the vibrator while the raised portions formed on each of the second group of rolls are held in contact with / the top ends of ridges in the corrugations of the sheet, then the top ends of corrugations are forced to expand sideways, causing the projections to be increased in wall thickness and -22 36978/2 to be reinforced in strength at the expense of resilience.

Fasteners having corrugations composed of ridges and grooves as illustrated in Fig. 15 through Fig. 24 can be easily manufactured by flattening the grooves of¾6 corrugations on the discs 44 and 63.

In the fasteners so far described, the strips of oorrugationsformed in the longitudinal direction of the sheet are Joined only at the middleo of the height from the ridges to the grooves. Thus, they sometimes tend to be tom apart along the strips of corrugations.

To preclude the possibility of such tearing, extra strength may be conferred by increasing the wall thickness of the said joined portions.

Fig. 36 and Fig. 37 illustrate one such embodiment. At the middle of the height from ridges to grooves tb® the corrugations 48 formed on each disc contained in the roll 42, fin-molding portions 71 are formed on the lateral edges.

When the sheet is passed through a pair of opposite rolls each composed of a plurality of discs of corrugated peripherles incorporating such fin-molding portions 71, the resin texture of the sheet fills the cavities of the said fin-molding portions. Consequently, the fastener to be obtained enjoys enhanced strength because of padded portions 16 formed around the joined portion of strips as illustrated in Fig. 37. The embodiment illustrated in Fig. 38 and Fig. 39 has stepped portions 72 formed at the middle of the height from ridges to grooves in the corrugations 48 of the roll 42.

When the sheet is passed through a pcfa. of opposite rolls each possessed of such st0?P^e8 portions 72, steps 17 are

36978/2 formed midway between ridges and grooves in each strip of corrugationsi Since the adjoining strips of corrugations are joined along the width of the steps, 17, the resultant fastener enjoys an increased strength.

The embodiment illustrated in Fig. 40 incorporated reinforcing members b^״ at the joined portions of strips of waves a. The reinforcing members b are firmed on the lateral sides along which ridges and grooves are separated starting from the joined portions of the adjoining strips of corrugations. Thus, the corrugated strips are joined by means of the joined portions and the reinforcing members.

When the reinforcing members ״b are extended as far as the side of the projections fanned in the corrugated strips, they stabilize the strips of corrugations greatly so aS to preclude possible tearing or deformation.

Such reinforcing members can be formed by utilizing the resilience of the sheet, l.e. minimizing the thickness of corrugations in each disc־:׳contained in the first group of rolls.

A general description has been given of the present invention.Fasteners manufactured by means of the device of this invention can be effectively applied in all the fields of conventional press-on and split-off type fasteners.