WO1997028378A1

WO1997028378A1 - Holder for threaded details

Info

Publication number: WO1997028378A1
Application number: PCT/SE1997/000146
Authority: WO
Inventors: Pawel Muszynski; Ove Agdahl
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 1996-02-01
Filing date: 1997-01-30
Publication date: 1997-08-07
Also published as: SE9600365D0; SE9600365L; SE506426C2; AU1680297A

Abstract

A holder for holding threaded members (10) includes a cage-part (1), a cover element (5) on one edge (11) of the cage-part, and holder securing means. The holder is comprised of an electrically insulating material and the cage-part (1) includes a recess (9) whose shape coincides with the shape of the threaded member (10). The cover element (5) is bendable across the threaded member (10) and the holder securing means include a spacer element (7) disposed on the cover element (5) and carrying a flange-like counter-pressure means (8) on its free end.

Description

Holder for threaded details

FIELD OF INVENTION

The present invention relates to an electrically insulating holder for screw-threaded members.

DESCRIPTION OF THE BACKGROUND ART

Structural components may often be secured with the aid of screw joints. The main advantage with screw joints is that they can be loosened and tightened quickly and in a simple fashion without causing unnecessary damage to the joints. However, when a screw joint consists of a screw and a nut two tools are required to establish and loosen the joint. When the components to be interjoined have different shapes and are located in confined spaces, it is often difficult to readily loosen or secure one part of the screw joint, due to lack of space. Accordingly, different solutions have been proposed with the aim of holding firm one component of a screw joint, often the nut, so as to require the use of only one tool in loosening and establishing a screw joint.

Prior publication FI 933 089 describes means for securing chassis nuts. The holder is comprised of a metal tab that has been bent around the nut . The two free ends of the metal tab include locking elements which hold the device firmly on a metal plate for instance.

The problem with this solution is that the two mutually joined parts come into electrical contact with one another, which is not always suitable. SUMMARY OF THE INVENTION

Structural components that are assembled with the aid of screw joints may be configured or positioned in a way that renders one part of a screw joint inaccessible, therewith making it difficult to establish and loosen a screw joint. One example in this regard is when devices, such as rectifiers, are to be secured in a magazine. So-called metal cage nuts or captive nuts are normally used in cases such as these. It may sometimes be necessary to use an insulated mount when fitting such devices, therewith eliminating the possibility of using a cage nut.

The aim of the present invention is to solve the aforesaid problems with the aid of a holder that consists of an electrically insulating material and that includes a bottom cage-part adapted to accommodate a threaded member, at least one cage-part cover means, and a holder securing means.

The object of the invention is to provide a removable threaded-member holder that insulates at least two components of a screw joint electrically from one another, while enabling the holder to replace existing metal cage- nuts .

The cage-part includes a recess whose shape coincides with the outer contours of the threaded member. The rim of the cage-part carries one or more bendable cover elements. When the cover elemen (s) is/are are bent across the threaded member, the cage-part will form together with the cover element/elements a holder which embraces the threaded member in an electrically insulating fashion. A screw or bolt receiving hole extends through the bottom of the recess in the cage-part that accommodates the threaded member, and also through the bendable cover element .

The holder also includes means for securing the holder. These holder securing means may be placed on the bendable cover element . The holder securing means may have the form of a tubular spacer placed centrally on the cover element, and flanges provided on the free end of said tubular spacer. These flanges may be intended to grip around the hole-defining surface of a lock plate, or directly around the hole-defining surface of the object to which the holder shall be secured.

One of the advantages afforded by the invention is that the holder components, such as cage-part, cover element and lock plate may be moulded in the one and the same mould. The moulded material may be an electrically insulating material, such as a polymeric material.

Another advantage is that the shape and size of the holder can be readily adapted to existing holes that have been used in respect of metal cage nuts.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a perspective, exploded view of an inventive holder for threaded joint members. Figure 2 is a side view of the same threaded member holder as in Figure 1, but shows the holder in an assembled state. Figure 3 is a side view of an alternative embodiment of a threaded member holder. Figure 4 is a perspective, exploded view of an alternative embodiment of a threaded member holder.

Figure 5 is a perspective view of a similar alternative embodiment of the holder according to Figure 3.

DETALED DESCRIPTION OF PREFERRED EMBODIMENTS

Figure 1 illustrates an exemplifying embodiment of a threaded member holder. The holder includes a cage-part 1 which includes a recess 9 for accommodating a threaded member 10. The shape and size of the recess coincide with the outer contours of the threaded member 10. In the illustrated embodiment, the depth of the recess 9 is the same as the thickness of the threaded member 10. Provided in the bottom of the recess is a hole 3 which is intended to receive the screw/bolt to be screwed into the threaded member 10. Cover elements 5 which function to insulate and cover the threaded member 10, i.e. nut 10, are provided on two mutually opposing edges of the cage-part 1. These insulating and covering elements 5 can be bent, or folded in towards one another so as to form a cover for the nut 10. Each element 5 includes one half of a spacer element 7. The spacer element 7 is positioned so that when the insulating and covering elements 5 are folded or bent in towards one another, the spacer element 7 will be seated centrally on the cover that extends across the threaded member 10 and formed by said elements 5. The hole extending through the spacer element 7 and the hole provided in the bottom of the recess in the cage-part are in register with the threaded member 10. The spacer element and flange-like counter-pressure means 8 provided thereon form holder fastening means together with a lock plate 20. The lock plate 20 includes a hole 24 whose shape coincides with the flange-like counter-pressure means 8 on the spacer element 7. The size of the hole is, on the other hand, slightly smaller than the outer contours of the counter-pressure means 8. This is because the lock plate 20 shall be pressed firmly beneath the flange-like counter-pressure means 8. The edge of the hole is bevelled on one side of the lock plate 20, as shown at 22. The bevel 22 has the same size and shape as the counter-pressure means 8 on the spacer element 7, such that said flange-like counter-pressure means 8 will not protrude out from the lock plate 20.

Figure 2 illustrates an assembled holder for threaded members 10. The holder is the same as that shown in Figure

1.

The holder is fitted onto one of the component members of a screw joint, by inserting the spacer element into a hole in said member and then threading the lock plate 20 over the flange-like counter-pressure means 8 on the outwardly projecting part of the spacer element 7. The flanges on the means 8 grip around the lock plate 20 and hold the holder in place . The shape of the hole is such as to prevent the holder from rotating when establishing the screw joint. The spacer element may have a square, hexagonal or some similar cross-sectional shape. The shape and size of the hole are adapted to the shape and size of the spacer element, so as to make rotation of the holder impossible.

It will be understood that the cover elements on the cage- part 1 may be fewer or more than two in number. For instance, a cover element 5 may be provided on one of the edges 11 of the cage-part, as evident from Figure 3 and Figure 5. As beforementioned, the cover element 5 carries a holder securing means, for instance a spacer element 7 that has a flange-like counter-pressure means 8 at its free end. Locking elements 2, 6 may be provided on one edge 11 of the cage-part such as to prevent the threaded member 10 falling away while securing the holder to the object, said locking elements 2, 6 having the configuration shown in Figure 3 and Figure 5. In the Figure 3 embodiment, the locking elements comprise two holes 6 provided on an edge opposite to the side on which the cover element 5 is mounted. These holes 6 receive two pins 2 provided on the cover element 5. The shape, size and mutual spacing of the pins 2 are adapted to the shape, size and mutual spacing of the holes, such as to obtain a firm but easily dismantled snap- connection. The holder of the Figure 5 embodiment has corresponding locking elements, although in this case the positions of the pins and holes is the reverse of the positions of the pins and holes in the Figure 3 embodiment.

Another conceivable way of securing the the holder to one of the members of a screw joint instead of using the aforesaid lock plate 20 is as follows. For instance, each of the at least two parts of the cover means 5 may include one part of a spacer element 7 placed on the centre of the cover. The free end of the spacer element 7 will carry a spring device 12, cf. Figure 4. The spring device 12 is then placed between the two spacer element parts 7. When the spring device 12 is compressed, the flange-like counter-pressure means on the spacer element parts 7 will fit exactly in the hole in which the holder shall be secured. When the spacer element parts 7 have been pressed far enough through the hole, the spacer element parts 7 will spring apart. The flange-like counter-pressure means 8 then grip the edges of the hole on said member, instead of the hole 20 of the lock plate as in the previous embodiment.

The holder components, such as cage-part, cover means, including the spacer element, and lock plates can be moulded in one and the same mould. The moulding material will be an electrically insulating material, e.g. a polymeric material, in order to obtain the electrically insulating properties.

Claims

1. A holder for holding threaded members (10) , comprising a cage-part (1) , a cover element (5) on one edge (11) of the cage-part, and holder securing means, characterized in that the holder is comprised of an electrically insulating material; in that the cage-part (1) includes a recess (9) whose shape coincides with the shape of the threaded member

(10) ; in that the cover element (5) is bendable over the threaded member (10) ; and in that the holder securing means includes a spacer element (7) mounted on the cover element

(5) and carrying a flange-like counter-pressure element (8) on its free end.

2. A holder according to Claim 1, characterized in that the spacer element (7) is positioned so that its centre line coincides with a hole in the threaded member (10) and also with a hole (3) in the recess (9) .

3. A holder according to Claim 2, characterized by locking means on at least one edge (11) of the cage-part and in corresponding positions on the cover element (5) .

4. A holder according to Claim 3, characterized in that the locking means comprises pins (2) on the cover element (5) and corresponding pin-receiving holes (6) on one edge (11) of the cage-part.

5. A holder according to Claim 3, characterized in that the locking means comprises pins (2) on one edge (11) of the cage-part and corresponding pin-receiving holes (6) on the cover element (5) .

6. A holder for threaded members (10) comprising a cage- part (1) , at least two cover elements (5) disposed on edges

(11) of the cage-part, and holder securing means, characterized in that the holder is comprised of an electrically insulating material; in that the cage-part (1) includes a recess (9) whose shape coincides with the shape of the threaded member (10) ; in that the cover elements (5) are bendable across the threaded member (10) ; and in that the holder securing means include a spacer element (7) disposed on the cover element or cover elements (5) and carrying a flange (8) on its free end.

7. A holder according to Claim 6, characterized in that the cover elements (5) are disposed symmetrically over the threaded member (10) ; in that the spacer element (7) comprises as many parts as the number of cover elements (5) on the cage-part (1) ; and in that the centre line of the spacer element (7) coincides with the centre line of the threaded member (10) .

8. A holder according to Claim 7, characterized in that the holder is adapted to be held firmly in a hole on an object by virtue of the flange-like counter-pressure means (8) of the at least two-part spacer element (7) having an outer shape and size that are adapted to the shape and size of the hole in said object; in that said spacer element (7) is resilient in the radial direction of said hole; and in that the flange-like counter-pressure means (8) on the spacer element (7) functions to grip around the edge of the hole in said object.

9. A holder according to any one of the preceding claims, characterized in that the holder is adapted to be held firmly to one of the members of a screw joint with the aid of a lock plate (20) which is adapted to be pressed firmly beneath the flange-like counter-pressure means (8) on the spacer element (7) against said object; and in that the flange-like counter-pressure means grips in a recessed portion (22) of the lock plate (20) .