EP1153552B1 - Slider for a plastic fastener tape - Google Patents

Abstract

The slider for a fastener strip with a center piece (8), two inner surfaces (31, 32) converging towards one another and two support flanks (14, 15) is provided with an additional center piece (7) which is located within the zone of the inner surfaces (31, 32). Also claimed are a fastener strip with such a slider, and a bag, preferably consisting of a plastic material with such a fastener strip.

Description

The invention relates to a slider for a fastener tape. It further relates to a closure tape with such a slider and a bag, preferably made of plastic, with such a closure tape.

Such slides and fastener tapes, which may also be referred to as profiled strip closures or sliding closure strips or tapes, are already known. Most of the known slides are individually manufactured by injection molding and then automatically applied by means of complicated devices individually on the slide fastener tapes. In most of these slides, it is necessary that they are fed via so-called Rütteltöpfe - aligned in the mounting direction - a device that spreads the slider and then presses it astride the previously opened fastener tape.

Such a device is known for example from DE-PS 31 36 075. Here, the sliders are successively fed to a rotor which grips the upper part of the slider, while the side parts (wings) of the slider are slowly spread in a stator and then pushed by the rotor onto the sliding closure band.

Other systems use complicated foldable pushers, the side parts (wings) are horizontal and hinged on the hinge during assembly. Such a slider is known from PCT / WO 95/35057.

All these methods have the disadvantage that on the one hand the slide production is costly and on the other hand, the assembly of the slide requires complicated facilities that are very prone to failure and allow only a relatively slow production.

From DE-PS 16 32 574 slider and a method for their application are known in which the U-shaped slide are mounted astride slide closure strips. The continuous strip forming closure strips are moved stepwise, and in each case a slider is pressed with a stationary fastener tape by a plunger on the tape.

DE-OS 21 01 875 describes a device for applying slides on complementary closure elements, the intermittently push past the device, wherein from an endless chain of elastic slides in each case a slide from the chain is pressed onto the tape. The slider side panels (wings) are flexurally elastic, so that they spring back after the slight spreading and pressing and the closure band functionally include. With this method, a low-noise manufacturing with relatively high speed is possible. A major disadvantage, however, is that the slider due to their small size are accepted by consumers only conditionally. They are not very handy and can be torn off the fastener tape with rough handling. Another disadvantage is that these slides have only in the front part of a very short arrow-like heart with inward-reaching flanks. These flanks prevent by holding the profile parts of the fastener tape pulling the slide upwards, but only in the front third of the slider. At the end of the slider, although there are small, inwardly directed flanks on the side parts, which are the sealing tape from the outside should include and prevent peeling or tilting of the slide. However, these flanks are so short that they can slide over the profile of the fastener tape even with little force and the slider then tilts upwards in its rear part. As a result, the closing function of the slider is no longer given.

EP-A-0 479 661 discloses a slider for a fastener tape having a center piece, two inner surfaces facing each other and two supporting flanks, the core extending over approximately half the length of the slider.

From DE 32 08 245 a slider for a fastener tape is known, which has on its upper side attachments through which the slider can be spread.

The object of the invention is to propose an improved slider for a fastener tape.

This object is solved by the features of claim 1. The slide, which is preferably made of plastic, comprises a heart, two mutually running inner surfaces and two supporting flanks. The slider may have a substantially U-shaped configuration. In this case, it consists of a base part and two adjoining side panels or wings. The closure band, which is preferably made of plastic, generally comprises two parts or sub-bands with profiles that can interlock. The slider is used for sliding or sliding assembly and separation of the fastener tape or the interlocking profiles or parts. By running towards each other inner surfaces of the slider, the interlocking parts of the fastener tape are moved towards each other. This is achieved by the decreasing distance of the inner surfaces of the slider. At one end of these inner surfaces of the centerpiece is provided by which the interlocking parts are kept at a distance. At the other end of the inner surfaces of the slider, the support flanks are provided. In this area, the interlocking parts are joined together; the fastener tape is hooked or closed.

According to the invention, a further frog is provided in the region of the inner surfaces of the slide. This is preferably a relatively small frog or a frog, which is smaller than the actual heart. The further centerpiece is located between the inner surfaces of the slider. It is also located between the actual heart and the supporting flanks. The further centerpiece holds with its side flanks the two profile parts the sliding closure band sure also to the middle part of the slider firmly and prevents tilting of the slider end upwards. According to the invention, the slide fastener tape halves are firmly guided and held to the middle of the slide; they are then taken over by the narrower end of the slider. On the now closed fastener tape, the slider is then still held by the smaller support flanks. If the sides of the slider should be slightly bent apart by a force such as tearing, tilting of the slider at its top is prevented because the other center in the center of the slider holds the fastener tape.

The invention provides a slide, with which the disadvantages mentioned above can be avoided. The slider has a handy size. He is still easy to produce in a chain, so that a fast low-noise production is possible. By the invention, the disadvantage of the easy tilting of the slide in the rear part is prevented by two separate frogs are arranged with guide flanks in a row. In addition, the necessary for the functioning of the slide bending elasticity of the plastic used in each case is defined. Finally, the invention includes an improvement of a method of applying an endless chain of sliders to a slide fastener tape.

Advantageous developments are described in the subclaims.,

Preferably, the further centerpiece is connected to the other centerpiece. The connection is made by a thin bridge.

According to a further advantageous development, attachments are provided on the upper side of the slider. If the slider has a U-shaped configuration, the attachments are preferably located on the base part, on the side opposite the side walls or wings of the base part. The essays serve for Spreading or biasing of the slider when applying the slider to a fastener tape.

The slider is preferably made of HDPE, ie low density polyethylene (high density polyethylene). HDPE is easy to recycle using low density polyethylene (NDPE), which makes up most bags or pouches, but also polypropylene, which is increasingly producing more bags and fastener tapes.

The invention further relates to a closure tape, preferably made of plastic, which has a slide according to the invention, and a bag, preferably made of plastic, which is characterized by an inventive closure tape.

Fig. 1

einen Schieber nach der DE-OS 16 32 574 in einer perspektivischen Darstellung,

Fig. 2

einen erfindungsgemäßen Schieber in einer Draufsicht von unten,

Fig. 3

den Schieber gemäß Fig. 2 in einer Ansicht von vorne (auf die in Fig. 2 links gezeigte Seite des Schiebers),

Fig. 4

einen Schnitt längs der Linie A-A in Fig. 2,

Fig. 5

eine abgewandelte Ausführungsform, bei der das weitere kleinere Herzstück nicht durch einen Steg mit dem ersten größeren Herzstück verbunden ist,

Fig. 6

den Schieber gemäß Fig. 2 bis 5 in einer Draufsicht von oben,

Fig. 7

den Schieber und einen Stößel, wobei sich der Stössel in zurückgezogener Stellung befindet und

Fig. 8

den Stössel beim Aufdrücken des Schiebers auf das Verschlußband.

Embodiments of the invention are explained below with reference to the accompanying drawings in detail. In the drawing shows

Fig. 1

a slider according to DE-OS 16 32 574 in a perspective view,

Fig. 2

a slide according to the invention in a plan view from below,

Fig. 3

2 in a view from the front (on the left in Fig. 2 shown side of the slider),

Fig. 4

a section along the line AA in Fig. 2,

Fig. 5

a modified embodiment in which the further smaller centerpiece is not connected by a web to the first major centerpiece,

Fig. 6

the slider of FIG. 2 to 5 in a plan view from above,

Fig. 7

the slide and a plunger, wherein the plunger is in the retracted position and

Fig. 8

the plunger when pressing the slider on the fastener tape.

Fig. 1 shows a slider of the known type in a perspective view. The slider 30 is designed substantially U-shaped. It has a base part 6 and two side parts 4 and 5 projecting therefrom, which can also be referred to as wings. The inner surfaces 31, 32 of the side parts 4, 5 converge towards each other. Their distance from each other decreases in a direction opposite to the direction of the arrow 33.

At one end of the inner surfaces 31, 32 a centerpiece 1 is arranged. It is located at that end of the slide on which the distance between the inner surfaces 31, 32 is greatest. The downwardly arrow-shaped heart piece 1 has lateral flanks 2, 3, which together with smaller flanks of the side walls 4, 5 and the side walls 4, 5 and corresponding side walls of the core 1 form separate inlet channels for the closure profile parts.

At the other end of the inner surfaces 31, 32 support flanks z are provided, which project from the inner surfaces 31, 32 inwardly and which together with the inner surfaces form an outlet channel.

The slider 30 is pressed down on a closure tape. Here, the side walls 4, 5 give way to the outside until the fastener tape is in the slide. In this position, a respective closure profile runs through one of the two inlet channels on both sides of the frog 1. At the other end of the slider, the latched or assembled fastener tapes pass through the outlet channel.

In the slider of the known type shown in Fig. 1, the flanks 2, 3 of the core 1 are only very short. These flanks 2, 3 hold the slide together with the flanks of the side walls 4, 5 fixed in its front part on the sliding closure profile. The other, the heart piece 1 facing away from the end of the slide is tapered and presses the two closure profile parts when moving the slider in the direction of arrow 33 together, so that then the fastener tape is closed. When moving the slider in the opposite direction (opposite to the direction of the arrow 33), the core 1 separates the two closure profile parts to open the shutter.

The rear, the heart piece 1 facing away from the part of the slider 30 is on the fastener tape only by short flanks or support flanks z, which protrude from the side parts 4 and 5 inwardly held. This allows the slider 30 slip at this point by stretching the side parts 4, 5 on the closure profile and tilt upwards, which leads to functional failure.

FIGS. 2 to 6 show a slide according to the invention. As can be seen from Fig. 2, there is another (second), smaller centerpiece 7, which is located between the front (first, actual), larger heart piece 8 and the rear end of the slider. The further core 7 is also located between the inner surfaces 31, 32. It has outwardly facing support flanks 12, 13. Further, the second core 7 is connected to the core 8 by a thin web 24.

The outer ends of the support flanks 16, 17 of the core 8 are spaced from the inner ends of the inwardly projecting from the side walls 20, 21 supporting flanks 18, 19. As a result, slots 9, 10 are formed for the halves of the fastener tape. Supporting flanks 14, 15 are provided on the end of the slide opposite the center piece 8, which protrude inwards from the inner surfaces 31, 32. The inner ends of the support flanks 14, 15 are spaced apart, whereby an opening 11 is formed.

In operation, the two fastener tape halves of the slide fastener tape run separately through the two slots 9, 10 when the slider is moved in the direction of the arrow 33. The fastener halves are closed in the thinner rear part of the slider. They exit as a closed closure from the opening 11.

The further, second, smaller centerpiece 7 holds with its side edges 12, 13, the two profile parts of the sliding fastener tape securely to the middle part of the slide and prevents tilting of the heart piece 8 opposite slide end upwards. The slide fastener tape halves are firmly guided and held according to the invention to the middle of the slide; they are then taken over by the narrower end of the slider. On the now closed closure band, the slider is then still held by the smaller support flanks 14, 15. Should you then by tearing the side parts 20, 21 of the slider slightly apart and threatening the slide at its end facing away from the core 8 tilted up, yet holds the other, smaller centerpiece 7 in the middle of the slide this slide on the fastener tape.

In Fig. 3 you can see the slide of FIG. 2 from the front (of the slots 9, 10), ie at the inlet of the two fastener tape halves. The support flanks 16, 17 of the core 8 hold the fastener tape halves from the inside, while the support flanks 18, 19 of the side walls 20, 21 keep them from the outside firmly on the slide.

As can also be seen from FIG. 3, attachments 22, 23 are provided on the upper part of the slide, that is to say on the base part 6 thereof, which have a substantially rectangular cross-section which, however, is slightly rounded at the corners. These attachments 22, 23 are used for pre-spreading of the slider by a plunger, as shown in Figures 7 and 8.

Fig. 4 shows a section along the line A-A in Fig. 2. The heart pieces 8 and 7 are connected by a thin web 24 together.

In the modified embodiment shown in Fig. 5, the core pieces 8, 7 are not connected by a web, but separated from each other. This embodiment has the advantage that material is saved and that the side parts spread more easily when shooting the slide.

Fig. 6 shows the slider in a plan view from above. In addition to the closure tape inlet openings 9, 10 can be seen the support flanks 16, 17 of the (first, actual, larger) heart piece 8 and the outer, smaller support flanks 18, 19 on the side parts 20, 21. At (middle, smaller) another centerpiece. 7 the support flanks 12, 13 can be seen. The base part 6 has openings 34, 35. At the end of the slide, from which emerges the closed sliding closure band, the small support flanks 14, 15 are located on the side parts 20, 21.

Figures 7 and 8 show the interaction of the slider with a plunger 26 for spreading the slider. The plunger 26 has projections 27, 28 which are spaced from each other. The mutually facing surfaces of the projections 27, 28 are inclined to each other, in such a way that increases the distance between these surfaces with increasing distance from the plunger 26. In this way, a conical recess is formed by the mutually facing inner surfaces of the projections 27, 28.

In the position shown in Fig. 7, the projections 27, 28 of the plunger 26 are spaced from the articles 22, 23 of the slider. To shoot the slider on the fastener tape, the distance between the slider and the plunger 26 is reduced until the position shown in Fig. 8 is reached. Upon advancement of the plunger 26, the inner surfaces of the projections 27, 28 engage the attachments 22, 23. This exerts a pressure on the attachments 22, 23, which then moves these attachments 22, 23 towards each other in the manner shown in FIG , As a result, the side walls 20, 21 of the slider spread in the also shown in FIG. 8 apparent Something on, so that the slider can be easily pressed onto the fastener tape. Due to the bending elasticity of the slider, the side walls 20, 21 jump back after pressing; they then cover the fastener tape.

Of considerable importance for the trouble-free application of the slide according to the invention is its bending elasticity. On the one hand, the slider must spring back after spreading to its original position, on the other hand, this spreading may not go too hard. Furthermore, the slider body must not become brittle when spreading and for a long time afterwards. He must not get any cracks. Finally, the slide should reuse (recycle) together with the closure bag and the slide fastener tape.

To achieve this, the material must consist of the same or similar base material as the pockets or bags from which the slide closure bag is made. A particularly suitable plastic material is low density polyethylene (HDPE), which is highly recyclable with low density polyethylene (NDPE) from which most bags or pouches are made. More and more, the bags and the closure tape are made of polypropylene. Together with this material, the slides can be recycled HDPE, that is ground and reuse. Such a material is, for example, a HDPE from Borealis A / S with a melt flow rate of 12 g / 10 min and a Shore hardness of 62.

The flexural elasticity of the slider has been studied by numerous experiments and may be e.g. to be defined as follows: experiments at the slide end, starting from an end opening on the sprayed 20-piece strand of 0.45 to 0.60 mm, measured at the free passage including the outer small supporting flanks 14, 15.

A slider is attached to its two molded connection sides of the chain by means of two clamps on a spring balance and loaded in the tensile test, the end opening of the slider as far as it is to the profilumgreifenden outer Support flanks 14, 15 on the strength of the fastener tape, about 1.8 mm, opens. This requires a tensile load of between 700 to 1300 grams. After completion of the tensile load takes place on the slide a provision of the end opening by its elasticity to 0.9 to 1.0 mm.

The slider is now permanently functional, that is he opens and closes the fastener tape safely without embrittling or tearing. He then has an end opening of about 1.8 mm, minus profilumgreifende outer support edges of about 0.4 mm, ie about 1.0 mm, and the closing pressure sustains permanently.

Claims (4)

1. Slider for a fastener strip, with a centre piece (8), two inner surfaces (31, 32) converging towards each other and two supporting flanks (14, 15), a further centre piece (7) being provided in the region of the inner surfaces (31, 32) between the centre piece (8) and the rear end of the slider, and the centre pieces (8, 7) being connected and separated from each other by a thin web (24).
2. Slider according to Claim 1, characterized in that attachments (22, 23) are provided on the upper side of the slider.
3. Slider according to Claim 1 or 2, characterized in that the slider is produced from HDPE
4. Fastener strip, preferably made of plastic, characterized by a slider according to one of Claims 1 to 3.

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