ATTACHMENT MEANS FOR A COVER PLATE OR THE LIKE

Abstract: To facilitate fastening of a cover plate to a rack cabinet for, e.g., telecommunications equipment and to obtain reliable and secure attachment of the plate, there is provided a plastic fastener device which is comprised of two interacting parts, i.e. a fastener part (2) and a pin (1). The fastener part consists in a pierced shaft portion which includes tabs or like appendages and two connected flange-like collars (6, 7). The pin is intended to be driven into the pierced shaft portion so as to deform the same. With the shaft portion inserted into a hole in a rack cabinet and a pin driven into the shaft portion, the shaft portion is deformed by virtue of conically shaped tab parts disposed therein, therewith fixating and securing the collared shaft portion in the hole. The cover plate can now be pushed between the two flange-like collars on the fastener device.

Description: DESCRIPTION Attachment means for a cover plate or the like TECHNICAL FIELD The present invention relates to a fastener device for secu- ring a cover plate or like element, said fastener device including a hole-mounted first fastener part which includes a cover plate supporting surface, and a second fastener part which interacts with said first fastener part and functions to fix and secure the first part in said hole, such as to provide a fastening for a cover plate or like element. DESCRIPTION OF THE BACKGROUND ART Fastener devices which consist in two interacting parts are previously known from DE-A 4,111,374 and SE-B 423,832. These known fastener devices include a first fastener part having a flange and a through-pierced portion for insertion into a hole, and a second fastener part which is configured for insertion into said through-piercing hole, wherein the insertable portion of the first fastener part is deformed as the second fastener part is inserted therein, so as to be able to secure a plate or like element. DISCLOSURE OF THE INVENTION For the purpose of readily securing a cover plate to a rack cabinet for, e.g., telecommunications equipment, such as to obtain reliable and secure fastening of the plate, there is provided a plastic fastener device which consists in two interacting parts, i.e. a fastener part and a pin. The fasten¬ er part is comprised of a pierced shaft portion and two connected flanged collars. The pin, which may be provided with a through-penetrating hole, is intended to be driven into the pierced shaft portion and therewith deform the same. The shaft portion includes conical tabs or like appendages which when the shaft portion is inserted into a hole on a rack cabinet and the pin is driven into the through-pierced shaft portion are deformed such as to affix and secure the collared shaft portion in said hole. The cover plate can now be pushed onto the fastener device, between the two collar flanges. The firmness with which the plate is secured and the ease with which the plate can be removed is determined by the distance between the collars and the thickness and shape of the plate. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 illustrates an inventive fastener device comprising an fastener part and a pin, and shows the device as a one- piece moulded article. Figure 2 illustrates the pin of the fastener device shown in Figure 1. Figure 3 is a sectioned view of the fastener part of the device shown in Figure 1. Figure 4 shows the pin partially inserted into the fastener part in Figure 3. Figure 5 shows different views of the fastener part in Figure 1. Figure 6 is a simplified illustration of part of a rack cabinet. Figure 7 shows the fastener part inserted in a hole on one part of a rack cabinet, and also shows an associated pin ready for insertion. Figure 8 shows respectively a front view and a side view of a cover plate. Figure 9 shows the cover plate and the fastener device from above. BEST MODE OF CARRYING OUT THE INVENTION Figure 1 illustrates an inventive fastener device, which in the illustrated case is delivered in the form of a one-piece plastic moulded product, with the pin 1 and the fastener part 2 joined together by a moulding part 3. As shown at 4 in Figure 2 , the pin is bevelled at both ends and includes a through- penetrating hole 5, partially for reasons of a moul¬ ding/technical nature. Figure 3 is a sectional view of the fastener part 2, which will be seen to include two flange-like collars 6, 7 and tabs or like appendages 8. The upper collar 6 is thicker than the lower collar 7 and includes a supportive surface 18. The thickness of the upper collar is determined partially to be able to withstand external forces, for instance to prevent the junction 9 between collar and shaft breaking should the pin be positioned obliquely (see Fig. 4) when being inserted into the fastener part, and such that the resistance afforded by the collar will assist in achieving correct alignment of the pin with a favourable force distri¬ bution from the collar to the shaft part carrying the tabs. The illustrated shaft includes five tabs. An odd number of tabs provides a better holding force than an even number of tabs, should the direction of an aperture or recess 15 in a cover plate 16 fail to coincide with two diametrically opposed tab interspaces. The width of the recess or aperture 15 is adapted generally to accommodate the diameter 17 of the fastener part 2 between the collars 6 and 7. Each tab 8 has a slightly curved outer side 10 and a slightly conical and inwardly directed inner side 11, such that as the pin is inserted into the region of the inwardly directed inner sides, the tabs will be forced elastically outwards, and the pin is held in place subsequent to being inserted. The fastener device is preferably made of a carbonate plastic, so as to have an acceptable impact resistance and so that the device will have an elasticity acceptable for its function. Figure 6 is a greatly simplified view of the lower part of a rack cabinet 12. The cabinet 12 includes a profiled section having on the underside thereof a transversely extendingplate which includes one or more holes 13 into which the fastener part of a respective fastener device shall be inserted. Figure 7 shows a fastener part 2 inserted into a hole 13 in a plate element from beneath. The outwardly slightly curved tabs with their bevelled ends can easily be pressed together for insertion into the hole, whereafter the tabs spring back to their original form and hold the fastener part in the hole in said plate and partially fixate the fastener part in said hole. With the fastener part in position in the hole and with the collar 7 resting against a surface around the hole 13 in the plate element 12, the pin 1 is driven up into the down¬ wardly facing hole 14 in the fastener part, the diameter of said hole being of a size which will enable the pin to be readily inserted over the first few millimeters with the application of a small force. When the pin has passed the region of the thinner collar 7, the pin will meet a further region which is delimited by the five tabs 8, which when no load is applied thereon decrease in a direction towards the centre axis of the fastener part, i.e. the inner surfaces of the tabs are slightly conical towards said centre axis. Further insertion of the pin from said region will cause the tabs to be forced out elastically against the resistance offered by the edge of the plate acting against the inner and thinner collar, and the fastener device is held firmly in the hole at the junction between the thinner collar and the tabs or like appendages. With the pin fully inserted in the fastener part, there is obtained a reliable and positive attachment of the fastener part and the fastener device will function effectively to support a cover plate on the suppor¬ tive surface 18 on the collar 6.

Claims: CLAIMS 1. A fastener device for securing a plate, such as a cover plate, comprising a fastener part (2) which includes a shaft for insertion into a hole (13) , and a pin (l) which interacts with the fastener part (2) andwhich is intended for insertion into a hole (14) extending through the fastener part and its shaft portion, such as to deform the fastener part elastically and therewith fixate and secure the fastener part in the hole (13) , said fastener device comprised of the fastener part and said pin functioning to secure a cover plate (16) , charac¬ terized in that the fastener part (2) includes two flange-like collars (6, 7) having an intermediate supportive surface (18) for receiving and supporting a cover plate (16) inserted between said two collars. 2. A fastener device according to Claim 1, characterized in that one collar (6) is thicker than the other collar (7) . 3. A fastener device according to Claim 1, characterized in that the shaft portion is comprised of an odd number of tabs or like appendages (8) , preferably five in number. 4. A fastener device according to Claim 3, characterized in that in the absence of deforming forces, the inner surfaces (11) of the tabs (8) slope towards a centre line. 5. A fastener device according to Claim 3, characterized in that the outer ends (11) of the tabs are bevelled. 6. A fastener device according to Claim 3, characterized in that the outer collar (6) has essentially the same thickness as the shaft portion (2) prior to the region (9) at which the shaft portion (2) merges with the tabs (8) . 7. A fastener device according to any one of the preceding Claims, characterized in that the fastener device (1, 2) is made of a plastic material. 8. A fastener device according to Claim 7, characterized in that the plastic is a carbonate type plastic.

Inventors: ESSENBERG CORRIE, ESSENBERG, CORRIE
Applicants: ERICSSON TELEFON AB L M, ESSENBERG CORRIE, ESSENBERG, CORRIE, TELEFONAKTIEBOLAGET LM ERICSSON
Application year: 1995
Main classification: F16B5
IPC codes: F16B5, F16B19, H02B1, H05K7