EP1309256A1

EP1309256A1 - Eyelet for reinforcing the edge of a hole in a carrier strip and device for attaching an eyelet to a carrier strip

Info

Publication number: EP1309256A1
Application number: EP01960266A
Authority: EP
Inventors: Heinz-Dieter Kopatz
Original assignee: William Prym GmbH and Co KG
Current assignee: William Prym GmbH and Co KG
Priority date: 2000-08-12
Filing date: 2001-06-02
Publication date: 2003-05-14
Anticipated expiration: 2021-06-02
Also published as: CN1446061A; US6907647B2; CA2418293A1; CN1209987C; DE20112908U1; PL360079A1; ES2230351T3; WO2002013646A1; EP1309256B1; ATE285688T1; MXPA03000586A; US20030167610A1; CZ200370A3; PL203329B1; AU2001281804A1

Abstract

The invention relates to a ringless eyelet ( 10 ') comprising a plate ( 11 ) arranged on the display side ( 23 ) of the carrier strip ( 20 ), and a tube-shaped collar penetrating the hole in the carrier strip. The hem of the collar of the eyelet element ( 10 ') is supported on the rear side ( 24 ) of the carrier strip ( 20 ). The aim of the invention is to connect the eyelet to the carrier strip ( 20 ) faster and in a more cost-effective manner. In order to achieve this, the free end part of the collar of the eyelet element ( 10 ') is provided with projections ( 16 ). An essentially closed ring profile ( 50 ), into which the collar projections ( 16 ) are integrated, is created when the collar is hemmed. After hemming, pressure points ( 40 ) are created on the carrier strip ( 20 ) between the collar projections ( 16 ) and the abutment surfaces ( 49 ) formed by the plate ( 11 ), said pressure points reliably holding the carrier strip ( 20 ). Said carrier strip ( 20 ) extends namely inside ( 51 ) the ring profile ( 50 ) beyond the pressure points ( 40 ). An eyelet is obtained using only one.

Description

Eyelet for reinforcing the edge area around a hole in a carrier web and device for attaching the eyelet to a carrier web ^•

The invention is initially directed to an eyelet of the type specified in the preamble of claim 1. One-piece and two-piece eyelets are known.

In the known one-piece eyelet of the type specified in the preamble of claim 1 (US Pat. No. 2,901,800, Fig. 5), the eyelet is formed by a single eyelet part, which consists of a plate with a short neck. At the front end of the neck there are spikes that sit at a radial distance from one another and act as projections of the neck. This rivet part is riveted via an additional sleeve-shaped rivet element, which can also be part of a rivet press. Only the prongs and not the neck of the eyelet are bent against the plate on which the sheet to be punched is located. The sheet is perforated through the front end of the tubular rivet element. After attaching the eyelet, the rivet element is removed and can be used again. The strength of the attachment of the eyelet to the leaf is unsatisfactory because only the occasional prongs are involved. The folded tines cannot prevent the leaf from pulling out at the eyelet-reinforced hole, because the points of the points point in the direction of such a pull-out movement.

There are one-piece eyelets of another type (DIN 7333), which have no projections, in which the end piece of the neck is flanged. These eyelets are mainly used for inflexible carrier webs, such as cardboard boxes. Until now, application on flexible carrier webs, such as car tarpaulins, was not possible. Before the Attaching the well-known one-piece eyelet, the box had to be pre-punched, which was cumbersome and time-consuming. After attaching, the eyelet supported itself on the face with its plate, penetrated the pre-cut hole in the box with its neck and its approximately L-shaped border came to rest on the back of the carrier web.

A pre-perforation of the carrier ba n is not necessary with other types of eyelets, namely two-part eyelets, which consist of an eyelet on one side and a disc part on the other side of the carrier web (DIN 7332). With these two-part eyelets, canvas can also be used as a carrier sheet, but a higher amount of material in the manufacture and a greater amount of work in the attachment are required. This is because both the eyelet part and the disk part have to be produced separately, and both parts have to be arranged in the associated upper and lower tools of the attachment device. The production, warehousing and feeding of two parts each is space and time consuming. The pull-out strength of the eyelets is also limited. If one wanted to try to omit the disc part from this known two-part eyelet, and only to work with an eyelet part, as in the aforementioned first prior art, one would obtain a completely unusable pull-out strength of the supporting track on the attached eyelet.

In the case of two-part eyelets, which are designed as so-called "grommets", the ring-shaped disk part has individual prongs on both the inner edge and the outer edge, which are pressed axially against the plate of the eye part during the flanging and thereby perforate the carrier web. These prongs are on the face side The carrier web, in the plate area of the eyelet, is bent or flanged by the transition between the neck and the plate from the eyelet and, on the other hand, by a peripheral chamber on the plate of the eyelet This eyelet is also very complex to manufacture and process.

The invention has for its object to develop an inexpensive, quickly attachable eyelet, which after its attachment to the carrier web by a high Excellent tear resistance. This is achieved according to the invention by the measures set out in claim 1, which have the following meaning.

With the axial or radial projections on the free end piece of the neck, holding means are obtained which, when the neck is flanged, produce special pressure points on the detected carrier web, against which the carrier web is subject to tensile stresses. In the ring profile of the flanging of the neck, the end-side neck projections are integrated and, with the interposition of the hole edge region of the carrier web, lie against abutment surfaces which are formed in this ring profile by the plate or by the transition between plate and neck of the neck part. The carrier web runs inside the ring professional beyond the pressure points up to its perforated edge. Stresses on the carrier web act as obstacles at the pressure points on the inside of the ring profile with rolled-up edges of the perforated web. The eyelet according to the invention is considerably more reliable than the prior art mentioned at the outset.

In comparison with the much more complex two-part eyelets, the invention gives a surprisingly high pull-out strength, namely a 30 to 75% higher strength. This occurs particularly with the previously so critical flexible or stretchable carrier webs that could not be processed with a one-piece eyelet. Because of the one-piece design of the invention, one saves the pane part and thus material, storage costs, freight costs and handling during the preparation work. The one-piece eyelet part in the invention allows rapid processing, which lowers the cost of attaching the eyelet. Taking into account the ring profile during the flanging, it is sufficient to make the neck of the eyelet according to the invention sufficiently long. Of course, the thickness of the support wall must also be taken into account. Then only the axial or radial projections need to be arranged in the free end piece of the neck, which can be created in different ways.

One possibility is to form the projections, for example, by radial perforations in the tube wall of the neck. When the neck is flanged over, these radial projections penetrate into the gripped edge area of the carrier web, where they dig in and create the pressure points with respect to the opposite abutment surface on the plate. In terms of production, however, it is simpler to form the other possibility, namely the projections axially. The toothed or corrugated end edge of the neck mentioned in claim 2 is suitable for this. In this case, the entire edge of the neck is continuously profiled and not, as in the prior art mentioned at the outset, provided with individual projections which are spaced apart from one another. In the ring profile, both the neck and its projections are deformed together in the invention. When the ring shape is pulled during the flanging, the tooth digs into the web material and there is not only a clamping between the tooth and the abutment surface from the plate, but also a positive fit between the tooth and the carrier web. The greater the tension exerted on the carrier web, the more reliably the tooth digs into the carrier web. This explains the surprisingly high tear strength of the eyelet according to the invention.

The invention further relates to a device for attaching the eyelet according to the invention. The resulting peculiarities can be found in claim 10. In the known attachment devices for eyelets on flexible carrier webs, such as tarpaulins, pulling pins are used on the end face of an axially movable central insert in the upper tool. This made it possible to cut the hole in the carrier web larger during the flaring stroke of the two tool parts in order to obtain problem-free riveting with the disk part. The invention takes a completely different path here.

Although, as has already been said, the invention does not use disc parts but only eyelet parts, a device is used which is customary for the two-part eyelets. In contrast, however, no pulling pin is used on the central insert of the upper tool, because the invention wants to make the hole in the carrier web as small as possible. This is important because, as has already been mentioned, in the formation of the essentially closed ring profile of the flange, an excess length from the hole edge region of the carrier web is desired, which continues inside the ring profile beyond the pressure points mentioned. A particularly reliable mode of operation is obtained if the pressure ring mentioned in claim 11 and the in Claim 13 counter pressure ring used. The profiles of these pressure and counter pressure rings mentioned in the further subclaims are also useful.

Further measures and advantages of the invention result from the subclaims, the following description and the drawings. In the drawings, the invention is shown in one embodiment. Show it:

1 and 2, each in plan view, the front or the back of a carrier web equipped with the eyelet according to the invention,

Fig. 3, in high magnification, a cross-sectional view through the in

1 shown attached eyelet along the section line III - III,

4 shows an axial section through the special eyelet part of the diskless eyelet according to the invention in the initial state, namely before it is processed on the carrier web,

Fig. 5, in enlargement, a flat bend of a portion of the section. V in Fig. 4 marked edge area of the inventive eyelet and

Fig. 6, in axial half section, fragments of a two-part device according to the invention for processing the eyepiece shown in Fig. 4, wherein the upper tool is located opposite the lower tool in the upper end point of its lifting movement.

1 and 2, an eyelet is intended to reinforce the edge region 21 of a hole 22 cut in a carrier web 20. The carrier web 20 is generally a flexible and possibly stretchable structure, for example a motor vehicle tarpaulin. The invention achieves the desired hole reinforcement with a one-piece eyelet part 10. In FIGS. 4 and 5, the eyelet part 10 is shown in its initial state before Processing. 1, 2 and 3, on the other hand, show the eyelet part 10 'after its processing, in the finished state of use, during its hole reinforcement function.

The eyelet 10 can be divided into a curved, essentially radially extending plate 11 and an axially extending tubular neck 12. For reasons of better dimensional stability and for the annular flanging of the neck 12 to be described in more detail, the plate 11 has a curvature profile

13 provided. This results in a particularly striking arch-shaped transition

14 between the plate 11 and the neck 12. The free end piece 15 of the neck is provided with axial projections 16, that is to say in the direction in which the neck 12 extends. In the present case, these consist of an arc-toothed end edge 17 which can be seen in FIG. 5. This has the following special appearance.

The tooth tips 17 are provided with convex curves 27, while the tooth gaps 18 have concave curves 28. This creates a wave shape from the tooth profile 19. The waveform is asymmetrical. That is, the radius of curvature of the curves 27 of the tooth tips 17 is smaller than that of the curves 28 of the tooth gaps.

This eyelet part 17 is attached to the carrier web 20 in the device 30 shown in FIG. 6. The device 30 consists of essentially five parts which are axially displaceable with respect to one another in time. First of all, this includes a lower tool 32 which in the present case is stationary and which, on the other hand, carries a pressure ring 34 which is passively axially movable. Furthermore, the device 30 includes an upper tool 31 that is actively movable relative to the lower tool 32, with a central insert 33 arranged coaxially therein, which, in contrast, is also passively axially movable. Finally, the upper tool 31 is enclosed in the circumferential area by a counter pressure ring 54, which is also passively axially movable. The central insert 33 and the counterpressure ring 54 are force-loaded in the sense of the force arrows 35 and 55 against the lower tool 32, while the pressure ring 34 in the lower tool 32, also mirror image, in the sense of the force arrow 36 against the upper tool 31 under the action of a group of springs 56 stands, which are mounted in axial bores of the lower tool 32. The springs 56 are as Coil springs are formed, in the inside of which the pins 57 which are seated on the pressure ring 34 engage. The tool group 31, 33, 54 on the one hand and 32, 34 on the other hand are reciprocally movable, as illustrated by the movement arrow 37 of the upper tool group 31, 33, 54.

The counter pressure ring 54 is guided on the peripheral surface 63 of the upper tool 31. The force load 55 from the counter pressure ring 54 is generated by a compression spring 64, which is supported between a flank of a peripheral flange 65 of the upper tool 31 and the abutment surface of a cutout 66 in the counter pressure ring 54. The extension position of the counter pressure ring 54 is determined by end stops. In the present case, these consist of the head 67 of a family of guide rods 68, which can be adjusted in length by thread 69 and a locking nut 71. The rod head 67 is supported at rest on the upper flank of flange 65. The desired extension length 70 of the counter pressure ring 54 with respect to the upper tool 31 is thereby determined.

As already mentioned, FIG. 6 shows the upper reversal point of the lifting movement 37, where the upper tool 31 is located at a maximum lifting distance 38 with respect to the lower tool 32. As a result, an eyelet part 10 can be conveniently inserted onto the receiving profile of the upper tool 31 and central insert 33. For this purpose, the upper tool 31 has a receptacle 39 corresponding to the profile of the plate 11. The area provided with the receptacle 39 is subject to wear when used as intended. To make it easier to repair a worn device 30, the lower region of the upper tool is therefore provided with an insert 31 ′, which is detachably connected to the upper region of the upper tool 31 by the indicated screw or the like. This insert 31 'has the receptacle 39.

After the insertion of the eyelet 10, the end of the neck 20 is supported on the peripheral surface of the central insert 33. The central insert 33 is provided with a flat end surface 43. To secure the position of the eyelet in the tools 31, 33, a holding element 44 is arranged in the circumferential area of the central insert 33, which in the present case consists of a pin which is spring-loaded radially outwards. Between the two tool parts 31, 32, the carrier web 20 is inserted, which is initially unperforated. The aforementioned springs 56 hold the pressure ring 34 in a defined starting position, which can be seen in FIG. 6. At the maximum stroke of the tools, the relevant upper side 45 of the pressure ring 34 is above or expediently at the same height with a cutting edge 42 provided in the cutting tool 32. This results in the pressure ring 34, a horizontal support plane 60 for the carrier web 20, which is illustrated in FIG.

During the downward stroke 37 of the upper tool group 31, 33, 54, the leading counter-pressure ring 54 first meets the carrier web 20 lying above the pressure ring 34. The two rings 34, 54 are provided with bevels 58 and 59 which run essentially parallel to one another and which support the carrier web 20 grasp between them, whereby the carrier web 20 is initially slightly tensioned. The inclined surface 58 of the pressure ring 34 extends at an acute angle 61 with respect to the support plane 60 illustrated in dash-dot lines in FIG. 6, which is determined by the end face 45 of the pressure ring 34 serving to support the carrier web 20. The counter pressure surface 59 of the pressure ring 54 mentioned runs essentially parallel to the pressure surface 58. When the two tools 31, 32 move against one another, the carrier web 20 is therefore drawn around the edge 62, which is formed between the end face 45 and the inclined surface 58 of the pressure ring 34. As a result, the carrier web is pulled smooth in the area 29 to be punched. The carrier web 20 consequently assumes an extended position in the support plane 60 mentioned.

Then the central insert 33 loaded by the press ram hits the upward facing side 23 of the carrier web 20 and presses it against the cutting edge 42 of the lower tool 32 resting on the carrier underside 24. A circular punched hole is thereby cut out of the carrier web 20. The hole radius 46 determined by the cutting edge 42 is smaller than the neck radius 26 of the eyelet neck 12 identified by 26 in FIG. 6.

If the upper tool 31 lowers further in the direction of the lifting movement arrow 37, the carrier web 20 becomes firmer between the two bevels 58, 59 of the two rings 34, 54 clamped. The neck 12 moves from the eyelet 10 through the hole formed in the lower tool until the plate 11 from the eyelet 10, with the interposition of the carrier web 20, touches the pressure ring 34. During this downward movement 37, the upper tool 31 overcomes the spring force 36 from the lower pressure ring 34 and the eyelet neck 12 and the axial projections 16 on the flanged profile 47 of the lower tool 32 are flattened. The spring force 54 from the upper pressure ring 54 is smaller than that on the Thrust ring 34 acting ejection force 36. Similar to the upper tool 31, the lower tool 32 also has an insert 32 'which is positioned in the axial region and which has the relevant flanged profile 47. This flared profile 47 wears out after prolonged use. Then it is sufficient to replace this insert 32 '.

The special riveting relationships shown in FIG. 3 result from the bordering. Practically the entire neck length 48 of the eyelet part shown in FIG. 4 is rolled into an annular profile 50 recognizable in FIG. 3 on the rear side 24 of the carrier web 20. The neck projections 16 are included in this ring formation 50. With the interposition of the hole edge region 21 of the carrier web 20 mentioned and also indicated in FIG. 6, these neck projections 16 are pressed against an abutment surface 49 generated by the described curvature 13 of the plate 11. The ring-shaped circumferential pressure points 40 can be seen there from FIG. 3. In the ring profile interior 51, the carrier web 20 continues with an end zone 41, which adapts to the profile 50 in the manner of a ring segment. Even when the end zone 41 rolls in during the riveting process, the bevels 58, 59 hold the carrier web 20 in place.

When the eyelet part attached to the carrier web 20 is used as intended, the force arrows 52 in FIGS. 1 to 3 show tensile loads which are illustrated. These tensile loads 52 are absorbed by the pressure points 40. At the pressure points 40 there is initially a clamping effect between the neck projections 16 and the abutment surface 49. In addition, because of the described profiling 19 of these projections 16, there is also a positive fit. The tooth tips 17 penetrate into the web material, however, because of the curves 27, 28 of the tooth profile 19, there is no formation of cracks in the web 20. A notching effect is thereby avoided. Before Tooth tips and also in the arched tooth gaps 18, beyond these pressure points 40, there is a step-like increase in the web thickness designated 53 in FIG. 3. The web 40 is in fact endeavored to rise back to its original web thickness 25 at 53. With the tensile loads 52 of the web 20, these step-like elevations 53 of the web material 20 cling to the wavy edges of the neck projections 16. This increases the positive fit and achieves a surprisingly high tensile strength of the riveted eyelet part 10 ′ on the web 20.

B e z u g s z e i c h e n l i s t e:

Outer part (initial state; Fig. 4) 'riveted state of 10 (Fig. 1 to 3) plate of 10 neck of 10, eyelet neck arch profile of 11 arcuate transition between 11, 12 end piece of 12 axial neck protrusion at 15 (Fig. 4) tooth tip ( Fig. 5) Tooth gap tooth profile at 15 (Fig. 5) Wear Erb ahn Lo chrandb er eich of 20 holes in 20 (Fig. 1, 2) face of 20 back of 20 web thickness of 20 (Fig. 6) neck radius of 12 ( Fig. 6) convex rounding of 17 (Fig. 5) concave rounding of 18 (Fig. 5) punched die from 20 (Fig. 6) device upper tool from 30 'interchangeable insert in 31 lower tool from 30' interchangeable insert in 32 central insert in 31 pressure ring in 33 force load arrow of 33 arrow of spring force of 34 stroke movement arrow of 31 versus 32 (FIG. 6) maximum stroke distance between 31, 32 receptacle in 31 for 11 pressure point of 20 between 16, 49 (Fig. 3) end zone of 20 beyond 40 (Fig. 3) cutting edge on 32 flat end face of 33 (Fig. 6) holding element for 10 at 33 (FIG. 6) end face for 20 to 34 hole radius of 29 (FIG. 6) flare profile in 32 (FIG. 6) neck length of 12 (FIG. 4) abutment surface on 11 for 16 (FIG. 3) ring profile of 12 at 10 '(Fig. 3) ring profile interior of 50 (Fig. 4) arrow of tensile load on 20 step increase from 20 behind 40 (Fig. 3) counter pressure ring force load of 54 spring for 36 pin on 34 for 56 slope of 34, slope slope counter slope of 54, counter bevel surface support plane angle course of 58 opposite 45 edge between 45, 58 of 34 circumferential surface of 31 compression spring flange cutout head of 68 guide rod threaded engagement extension length lock nut

Claims

Patent claims

1.) Eyelet for reinforcing the edge area (21) around a hole (22) in a carrier web (20),

with a discless eyelet part (10, 10'), which consists of a plate (11) resting on the visible side (23) of the carrier web (20), a tubular neck (12) passing through the hole (22) and an arcuate transition ( 14) exists between the plate (11) and neck (12),

wherein the free end piece (15) of the neck (12) is provided with projections (16),

and with a border of the neck (12) of the eyelet part (10') which is supported on the back (24) of the carrier web (20),

characterized ,

that the neck projections (16) run in the axial and/or radial direction,

that the completed flanging of the neck (12) has a substantially self-contained ring profile (50) into which the end piece (15) having the neck projections (16) is integrated,

that with the interposition of the hole edge area (21) of the carrier web (20), the neck projections (16) in the ring profile (50) are pressed against abutment surfaces (49) formed by the plate (11) or the transition (14) and pressure points (40) on the detected Generate a carrier web (20) against which the carrier web (20) stands under tensile loads (52),

and that the carrier web (20) continues in the ring profile interior (51) beyond the pressure points (40) to its hole edge (41).

2.) Eyelet according to claim 1, characterized in that the axial neck projections (16) consist of a toothed end edge (19) of the neck (12).

3.) Eyelet according to claim 2, characterized in that the tooth tips (17) are convex and the tooth gaps (18) are concavely rounded

and that both curves (27, 28) determine a wave shape of the tooth edge (19).

4.) Eyelet according to claim 3, characterized in that the toothed edge (19) has an asymmetrical wave shape.

5.) Eyelet according to claim 3 or 4, characterized in that the convex curves (27) of the tooth tips (17) are smaller than the concave curves (28) of the tooth gaps (18).

6.) Eyelet according to one of claims 1 to 5, characterized in that the material of the carrier web (20) is designed to be flexible and / or stretchable.

7.) Eyelet according to claim 6, characterized in that the carrier web (20) consists of a canvas tarpaulin.

>.) Eyelet according to claim 6, characterized in that the carrier web (20) consists of a reinforced plastic film.

.) Eyelet according to one of claims 1 to 8, characterized in that the hole diameter (49) of the carrier web (20) is smaller compared to the clear width between the diametrical ring profiles (50) of the flanged neck (12).

10.) Device (30) for attaching eyelet parts (10) to a carrier web (20) according to one of claims 1 to 9,

with a lower tool (32) having the flanged profile (47) for the neck (12) of the eyelet part (10),

with an upper tool (31) which accommodates the eye part (10) and is movable (37) relative to the lower tool (32),

the carrier web (20) being positioned between the two tools (31, 32),

characterized ,

that the upper tool (31) is provided with a central insert (33) which is axially movable against a spring force (35) and has an end face (43),

that the end face (43) of the central insert (33) is essentially flat and free of the pulling pins that pull the carrier web (20) deep,

that the lower tool (32) has an annular cutting edge (42), which acts with the end face (43) of the central insert (33) to cut holes (29) on the carrier web (20) in between,

and that the hole radius (46) of the cutting edge (42) is smaller than the outer radius (26) of the neck (12) of the eye part (10).

1.) Device according to claim 10, characterized in that a pressure ring (34) is arranged in the lower tool (32) at a radial distance from the flanged profile (47) and is force-loaded (36) in the direction of the upper tool (31),

that - seen at the maximum stroke of the two tools (31, 32) - the pressure ring (34) is essentially in the height range of the cutting edge (42) of the lower tool (32).

and that the pressure ring (34) creates a support plane (60) for the carrier web (20) to be placed between the two tools (31, 32).

12.) Device according to claim 11, characterized in that a helical compression spring has an annular end surface

and that this ring end surface forms the pressure ring (34) and the compression spring generates the force load (36).

13.) Device according to one of claims 10 to 12, characterized in that the pressure ring (34) is assigned a counter-pressure ring (54) in the upper tool (31) and is force-loaded (55) on the lower tool (32).

and that the carrier web (20) is clamped between the two rings (34, 54) during the lifting movement (37).

14.) Device according to claim 13, characterized in that for clamping the carrier web (20), the two rings (34, 54) are provided with two mutually facing inclined and counter-inclined surfaces (58, 59).

5.) Device according to claim 14, characterized in that the inclined surface (58) runs at an acute angle (61) pointing in the lifting direction (37) with respect to the support plane (60), which extends from the support surface (45) of the pressure ring (34). certainly,

and that the counter-inclined surface (59) of the counter-pressure ring (54) runs essentially parallel to the oblique surface (58) of the pressure ring (34).

16.) Device according to one of claims 10 to 15, characterized in that the upper tool (31) and / or the lower tool (32) are provided with inserts (31 'or 32') which hold the receptacle (39) and / or have the flanged profiles (47) for the eyelet part (10).