WO1992009813A1

WO1992009813A1 - Fastener insert device

Info

Publication number: WO1992009813A1
Application number: PCT/AU1991/000537
Authority: WO
Inventors: John Joseph Fitzsimon
Original assignee: Jack The Grippa Pty Limited
Priority date: 1990-11-21
Filing date: 1991-11-21
Publication date: 1992-06-11

Abstract

A fastener insert device (10) is formed from an expansible sleeve (11) acted upon by a conical member (18) fitted within the sleeve (11) whereby the member (18) is shaped to interact with the sleeve (11) to expand the sleeve (11) and grip the bore of a tube (2). Relative rotation between the sleeve (11) and the conical member (18) being restricted by the interaction between a projection (21) on the conical member (18) and the sleeve (11).

Description

FASTENER INSERT DEVICE

TECHNICAL FIELD The present invention relates to an expandable insert device adapted to radially engage an inside surface of a recess or hollow member for securing to another member. More specifically, but not exclusively, the device of the present invention is suitable for joining hollow members such as tubes to form a T-joint in a frame.

BACKGROUND ART Frames are often constructed from tubing into generally rectangular configurations wherein the corner joints and T-joints are usually formed by connecting joints which are adapted to receive the two or three or more ends of tubes which converge on the joint. This arrangement necessitates cutting the tubing to the appropriate lengths so that they extend between the various connections. A disadvantage of this system is that when the frame has been constructed and additional tubes are required to be connected within the framework, it is generally necessary for the frame to be disassembled, the tubing cut at the desired points to allow insertion of additional connections, and then re-assembled with the additional tubes and connections.

DISCLOSURE OF INVENTION In one broad form the present invention provides a fastener insert device comprising: a threaded elongate member having an enlarged head at one end; a generally elongate insert comprising an expanding means having a generally conical or wedge-shaped member movable, by means of the threaded elongate member, longitudinally of the insert within a co-operating tapered recess of an expandable member; guide means to generally prevent relative rotational movement, or to allow relative rotational movement between predetermined limits, of the conical member with respect to the expandable member, said guide means comprising a radial projection on the conical member, said radial projection being received in an elongate recess extending longitudinally of the expandable member. Preferably, one longitudinal side edge of the elongate recess is provided with engagement means for releasably engaging the projection, and wherein the other side edge is generally straight for allowing free sliding movement of the projection in both longitudinal directions. The predetermined limits allow less than 360° of rotational movement.

Appropriately, the guide means is at least one pin projecting radially outwards from the conical member.

Preferably, the conical or wedge member is threadedly engaged by the other end of the threaded elongate member, and wherein relative rotational movement between the wedge member and the elongate member in a predetermined direction causes the wedge member to advance towards the enlarged head of the elongate member. Alternatively, a nut threadedly engages the other end of the elongate member and bears against the wedge member and where, in use, relative rotational movement between the elongate member and the nut in a predetermined direction advances the nut towards the enlarged head of the elongate member.

The relative rotational movement between the elongate member and the wedge member, or the nut bearing on the wedge member, in the predetermined direction causes the projection on the wedge member to bear against the other straight side edge of the elongate recess, and wherein relative rotational movement in the opposite direction causes said projection to bear against the engagement means of the one longitudinal side edge of the elongate recess. Preferably, the enlarged head of the elongate member is adapted to be rotatably driven by a standard or Phillips head screw-driver.

In a further form, the enlarged head of the elongate member comprises an elongate piece pivotally mounted to the elongate member about an axis normal to the elongate member, and which is movable between a retracted position generally aligned with the elongate member and an extende position projecting transversely of the longitudinal direction of the elongate member. The pivotal axis of th piece is at a predetermined position therealong such that the head piece is caused to move by gravity into the retracted or extended position depending on the orientation of the elongate member.

In another embodiment of the present invention, a nu is joined to a resilient biasing means which is, in turn, joined to the wedge member for creating a resilient longitudinal biasing force between the elongate member which threadedly engages the nut and the wedge member.

BRIEF DESCRIPTION OF DRAWINGS Preferred forms of the present invention will now be described by way of example with reference to the accompanying drawings, wherein:

Fig. 1 is an exploded perspective view of a tubing assembly using the fastener device of the present invention;

Fig. 2 is a schematic perspective view of the device shown in Fig. 1;

Fig. 3 is a schematic perspective view of a variatio of the embodiment shown in Fig. 2 which is suitable for use with square tubing;

Fig. 4 is a schematic cross-sectional view of anothe embodiment of the present invention;

Fig. 5 is a schematic side elevational view of a bol having a retractable head of the embodiment of Fig. 4; Fig. 6 is a schematic perspective view of a preferre form of the wedge member;

Figs. 7 and 8 show adaptors for use with the present invention;

Figs. 9 and 10 show an alternative bolt head arrangement;

Fig. 11 shows a square section tube having an inwardly projecting dimple; and

Fig. 12 shows another manner of connection between a square section tube and the device of Fig. 3. BEST MODES OF CARRYING OUT THE INVENTION

The expandable fastener device 10 as shown in Fig. 1 is particularly suitable for joining a primary tube 1 to a secondary tube 2 to form a "T-joint" when constructing a frame or the like from the tubing. The device 10 comprises an expandable cylindrical member 11 provided with a guide slot 12 which extends in the longitudinal direction of the cylinder. The cylinder 11 is constructed from a resilient material and wherein a longitudinal expansion cut 24 extends longitudinally from end to end to allow the member 11 to resiliently radially expand. The wall thickness of the cylindrical member 11 is tapered so as to be thicker at a forward end 11A thereof.

Received within the cylindrical member 11 is a sliding .conical member 18 which tapers towards its forward edge 18A. The taper of the conical member 18 is approximately the same as the taper of the inside surface of the cylindrical member 11 such that the outside surface of the wedge member 18 generally bears against the inside surface of the cylindrical member 11. Sliding movement of the wedge member 18 towards the ^"forward edge 11A of the cylindrical member 11 causes the cylindrical member 11 to expand radially outwards.

The conical member 18 comprises a threaded aperture 19 which is adapted to engage a distal portion of an elongate bolt 17.

The wedge member 18 further comprises a radial projection 21 which is slidably received in the guide slot 12. One side edge 23 of the guide slot 12 is provided with serrations adapted to engage the projection 21 when it is caused to bear against the one side edge 23 and prevent the projection 21 from moving towards the forward edge 11A of the cylindrical member 11. The other side edge 25 of the guide slot 12 is generally straight to allow free movement of the projection 21 in both longitudinal directions when it is caused to bear against this side edge 25.

The guide slot 12 is closed at the both ends so as to generally prevent the conical member 18 from separating from the cylindrical member 11.

In use, a first hole (not shown) is drilled in the wall of the primary tube 1 which is large enough to permit the enlarged head of an Allen keyed bolt or the like to pass through. Another hole 4 is drilled in the wall of the primary tube 1 which is opposite to and aligned with the first hole 3. The second hole 4 is large enough to receive the shank of the Allen bolt but smaller in diameter than the enlarged head. In this way the shank 17A of the Allen bolt 17 can be inserted through each of the holes (3, 4) with the enlarged head being retained within the primary tube 1 by means of the smaller diameter hole 4, and wherein the shank 17A of the bolt 17 projects radially outwards from the primary tube 1.

The insert part of the device 10 is then inserted onto the shank 17A of the bolt 17 by engaging the threads of the bolt 17 with the threads of the recess 19 in the conical member 18. The secondary tube 2 is then inserted over the expandable part of the device 10. Preferably, the forward end of the secondary tube 2 is formed so that its edge may be caused to consistently abut the curved surface of the primary tube 1 or suitable adaptors provided. The secondary tube 2 is most easily inserted over the insert part of the device 10 when the conical member 18 is positioned furthest away from the forward edge 11A of the cylindrical member 11, and wherein the external diameter of the cylindrical member 11 is designed to fit snugly into the recess in the secondary tube 2. When the device 10 is fully inserted within the secondary tube 2, a screw driver or Allen key as appropriate may be used to rotatably drive the bolt 17. Due to a frictional engagement between the threaded shank 17A of the bolt 17 and the threaded internal recess 19 of the conical wedge member 18, rotational movement of the bolt 17 imparts a moment force on the conical member 18 so that the projection 21 is caused to bear against the straight side edge 25 of the guide slot 12 thereby allowing the conical member 18 to freely advance towards the forward end 11A of the cylindrical member 11. In this way, the cylindrical member 11 is caused to expand and engage the internal surface of the secondary tube 2. The rotational movement of the bolt will cause the forward edge of the secondary tube 2 to firmly abut the outside surface of the primary tube 1.

In order to release the device 10 from gripping the inside surface of the secondary tube 2, the bolt 17 is rotated in the opposite direction to cause the enlarged head of the bolt to move away from the wall of the tube while the cylindrical member remains wedged against the inside of the tube 2. A force may then be applied longitudinally against the bolt 17 to "knock" the conical member 18 towards the rearward end of the cylindrical member 11 and thereby disengage the clamping effect. The bolt can then be rotated counter-clockwise to impart a moment on the conical member 10 which causes the projection 21 to bear against the serrated side edge 23 of the guide slot 12 so as to allow the device 10 to be withdrawn from the tube 2 without allowing the conical member to again wedge within the expandable member 11. The device 30 shown in Fig. 3 operates in the same way as the device 10, except that it is adapted for use in a rectangular hollow section instead of round tubing. That is, there is provided a tapered member 38 having a threaded recess 39 and a radial projection 41, an expandable hollow rectangular member 31 having a guide slot 32 with one side edge 43 thereof having serrations, and the other side edge 42 being generally straight and a bolt or the like having an enlarged head at one end and a threaded shank which engages the threaded recess 39 of the tapered member 38. The hollow rectangular member 31 is preferably formed by two angled sections (31A, 3IB) each of which are attached to each other by respective resilient connections 33 located proximate the forward end 31C.

Figs. 4, and 5 show another embodiment of the present invention which allows the device to be engaged with the inside surface of the secondary tube 2 when it is to be connected to, for example, a flat surface which may be inaccessible from the other side. In this embodiment, a specially adapted bolt 71 having a retractable head piece 72 at one end is used. That is, the bolt 71 is provided with a slot 74 adapted to receive a head piece 72 which is pivotally mounted in the slot about a pivot axis 73. The head piece 72 is thereby movable between a retracted position, wherein the piece 72 is generally aligned with the shank 75 of the bolt 71, and to an extended position wherein the head piece 72 extends generally transversely to the longitudinal axis of the shank 75. The pivot axis 73 is positioned off-centre along the length of the head piece 72 so that the head piece 72 tends to move into the extended position unless the shank 75 is in a predetermined orientation wherein the centre of gravity of the head piece 72 acts to move it into the retracted position.

The bolt 71 is slidably received in the aperture of the conical member 18 which threadedly engages on the end of the bolt. In use, the head piece 72, in its retracted position, is inserted through a hole in a wall of the member to which the tube is being joined. The bolt 71 is then rotated so that the head piece 72 is caused to move into an extended position and, when the bolt is pulled back, the head piece 72 is caused to bear against the inside surface of the wall. The device 71 can then be positioned within a tube or rectangular hollow section. Rotational movement of the nut 76 causes the conical member to advance towards the forward end of the expanding member and thereby cause the expanding member to grippingly engage the inside surface of the tube.

The retractable head piece 72 may be provided with a tapered knife edge which engages the side edge of the hole in primary member and prevent undesired rotational movement of the bolt 71.

The head piece 72 may also be provided with snag projections (not shown) .

Shown in Fig. 6 is a preferred form of the wedge member 18 comprising a resilient spring 81 mounted longitudinally from the rearward face 82 of the wedge member 18 and with a threaded end member 83 mounted to the distal end of the spring 81 and adapted to threadedly engage the distal end portion of the threaded bolt of the device. In use, the resilient spring 81 provides continuous resilient pressure on the conical member. When, for example, the tube to which the fastener insert device is attached expands and contracts due to the changes in ambient air temperature, this arrangement allows a constant gripping pressure to be maintained against the inside wall of the tubing even when it expands and contracts.

Shown in Figs. 9 and 10 is a method for allowing the enlarged head of the bolt to be inserted through a pre-formed hole in the primary member 1 which, when correctly orientated after insertion, is adapted to engage a locating member 110 when attached to the strip 93. The strip 93 is also provided with an enlarged aperture 98 corresponding to the pre-formed hole (not shown) in the primary member (not shown) which only allows insertion of the enlarged head 101 of the bolt 100 when it is in a certain orientation. The aperture 98 is located between the holes 92 so as to also be aligned with a similarly shaped aperture 104 in the locating member 110. In use, the enlarged head is inserted through the co-operating apertures in the primary member (not shown) , strip 93 and locating member 110, and rotated by approximately 90 and pulled back whereby projections 103 on the enlarged head 101 engage recesses 111 in the locating member 110 thereby allowing the bolt 100 to be used with the fastener insert device 10.

Shown in Figs. 7 and 8 are adaptors 120, 121 which are adapted to be inserted over the expandable members of the fastener insert device to adapt the device for use with large size circular tubing or rectangular hollow section tubing.

A projection 135 on adaptor 120 is adapted to clip into slot 125A on device 10 of Fig. 1 while a similar projection 136 on adaptor 121 of Fig. 8 is adapted to clip into slot 125 on device 30 of Fig. 3.

The slot 138 in adaptor 120 and slot 139 in adaptor 121 enable the locking together of parts as shown in Figs. 11 and 12.

A slot 125 is located on the outer surface of device 30 of Fig. 3 and slot 125A on device 10 of Fig. 1 adjacent their respective forward ends 31C and 11A.

Slots 125 and 125A enable devices 30 and 10 to be locked into tubing or the like by means of a dimple or projection 127 formed inwardly of tubing 128 as shown in Fig. 11. The device 30 can be forced into the tube 128 so that dimple 127 clips into slot 125. Once the wedge member 38 is tightened inside body 31 the device 30 is more securely retained in the bore of component 128.

The adaptors 120, 121 have a similar construction to the expandable members to allow them to be expanded with the expandable members to thereby grip the internal surface of a tube or recess. It is envisaged that adaptors 120, 121 may be inserted over similar smaller adaptors which are in turn inserted over an expandable member.

An alternative arrangement is shown in Fig. 12 where a hole 129 is formed in tubing 128 and a pop rivet 130 or self tapping screw or the like is employed to more securely contain the device 30 in component 128. In similar fashion device 10 can also be secured into a bore. It is envisaged that the fastener insert device may be used to connect a variety of objects in many different applications. Appropriately, the fastener insert device can be shaped to fit differently shaped bores as required such as-'triangular or other multi-lateral shaped bores.

It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims

CLAIMS:-

1. A fastener insert device comprising: a threaded elongate member having an enlarged head at one end; a generally elongate insert comprising an expanding means having a generally conical or wedge-shaped member movable, by means of the threaded elongate member, longitudinally of the insert within a co-operating tapered recess of an expandable member; guide means to generally prevent relative rotational movement, or to allow relative rotational movement between predetermined limits, of the conical member with respect to the expandable member, said guide means comprising a radial projection on the conical member, said radial projection being received in an elongate recess extending longitudinally of the expandable member.

2. A device as claimed in Claim 1 wherein one longitudinal side edge of the elongate recess comprises engagement means for releasably engaging said radial projection.

3. A device as claimed in Claim 2 wherein the engagement means comprises a series of serrations formed along said one longitudinal side edge.

4. A device as claimed in any one of Claims 1 - 3 wherein the conical member is threadedly engaged by the other end of the threaded elongate member such that the conical member moves longitudinally relative to the expandable member under rotation of the threaded elongate member.

5. A device as claimed in any one of Claims 1 - 3, wherein the other end of the elongate member is threadedly engaged in a nut adapted to bear against the conical member such that relative rotation between the elongate member and the nut in one sense advances the nut toward the enlarged head of the elongate member.

6. A device as claimed in Claims 2 or 3 wherein relative rotational movement in one direction between the elongate member and the conical or wedge-shaped member causes the projection to engage the engagement means and relative rotational movement in the opposite direction causes the projection to be disengaged from the engagement means.

7. A device as claimed in any one of the preceding claims wherein the enlarged head of the elongate member comprises an elongate piece pivotally mounted to the elongate member about an axis transverse to the longitudinal axis of the elongate member, said piece being movable between a retracted position substantially aligned with the longitudinal axis of the elongate member and an extended position transverse to the longitudinal axis of the elongate member.

8. A device as claimed in Claim 7 wherein the pivotal mounting of the elongate piece is not at the centre of gravity of the piece.

9. A device as claimed in any one of Claims 1 - 3 wherein a threaded nut is connected to said conical member via resilient biasing means which provides a longitudinal biasing force to separate the nut from the conical member and further wherein the elongate member is adapted to threadedly engage the nut and the conical or wedge member. 10. A fastener insert device substantially as hereinbefore described with reference to Figs. 1 and 2 or Fig. 3 or Figs. 4 and 5 or Figs. 6, 7 or 8 or Figs. 9 and 10 of the accompanying drawings. AMENDED CLAIMS

[received by the International Bureau on 8 April 1992 (08.04.92); original claims 1-10 replaced by amended claims 1-19 (4 pages)]

1. A fastener insert device comprising: a threaded elongate member having an enlarged head at one end; a generally elongate insert comprising an expanding means having a generally conical or wedge-shape member movable, by means of the threaded elongate member, longitudinally of the insert within a co-operating tapered recess of an expandable member; guide means to generally prevent relative rotational movement, or to allow relative rotational movement between predetermined limits, of the conical member with respect to the expandable member, said guide means comprising a radial projection on the conical member, said radial projection being received in an elongate recess extending longitudinally of the expandable member, said elongate recess being closed at the end of the expanding means proximal the widest opening of the tapered recess.

4. A device as claimed in any one of Claims 1-3 wherein the conical member is threadedly engaged by the other end of the threaded elongate member such that the conical member moves longitudinally relative to the expandable member under rotation of the threaded elongate member.

5. A device as claimed in any one of claims 1-3, wherein the other end of the elongate member is threadedly engaged in a nut adapted to bear against the conical member such that relative rotation between the elongate member and the nut is one sense advances the nut toward the enlarged head of the elongate member.

7. A device as claimed in any one of the preceding claims wherein the enlarged head of the elongate member comprises an elongate piece pivotally mounted to the elongate member about an axis transverse to the longitudinal axis of the elongate member and an extended position transverse to the longitudinal axis of the elongate member. 8. A device as claimed in Claim 7 wherein the pivotal mounting of the elongate piece is not at the centre of gravity of the piece. -

9. A device as claimed in any one of Claims 1-3 wherein a threaded nut is connected to said conical member via resilient biasing force to separate the nut from the conical member and further wherein the elongate member is adapted to threadedly engage the nut and the conical or wedge member.

10. A fastener insert device comprising: a threaded elongate member having an enlarged head at one end; a generally elongate insert comprising an expanding means having a generally conical or wedge-shape member movable, by means of the threaded elongate member, longitudinally of the insert within a co-operating tapered recess of an expandable member; guide means to generally prevent relative rotational movement, or to allow relative rotational movement between predetermined limits, of the conical member with respect to the expandable member, said guide means comprising a radial projection on the conical member, said radial projection being received in an elongate recess extending longitudinally of the expandable member, one longitudinal side edge of said elongate recess comprising engagement means for releasably engaging said radial projection.

11. A device as claimed in Claim 10 wherein the engagement means comprises a series of serrations formed along said one longitudinal side edge.

12. A device as claimed in Claim 10 or 11 wherein the conical member is threadedly engaged by the other end of the threaded elongate member such that the conical member moves longitudinally relative to the expandable member under rotation of the threaded elongate member.

13. A device as claimed in any one of claims 10-12, wherein the other end of the elongate member is threadedly engaged in a nut adapted to bear against the conical member such that relative rotation between the elongate member and the nut is one sense advances the nut toward the enlarged head of the elongate member.

14. A device as claimed in any one of Claims 10-13 wherein relative rotational movement in one direction between the elongate member and the conical or wedge-shaped member causes the projection to engage the engagement means and relative rotational movement in the opposite direction causes the projection to be disengaged from the engagement means.

15. A device as claimed in any one of claims 10-14 wherein the enlarged head of the elongate member comprises an elongate piece pivotally mounted to the elongate member about an axis transverse to the longitudinal axis of the elongate member, said piece being movable between a retracted position substantially aligned with the longitudinal axis of the elongate member and an extended position transverse to the longitudinal axis of the elongate member.

16. A device as claimed in Claim 15 wherein the pivotal mounting of the elongate piece is not at the centre of gravity of the piece.

17. A device as claimed in any one of Claims 10-16 wherein a threaded nut is connected to said conical member via resilient biasing means which provide a longitudinal biasing force to separate the nut from the conical member and further wherein the elongate member is adapted to threadedly engage the nut and the conical or wedge member.

18. A device is claimed in any one of the preceding claims wherein said expandable member comprises a slot or recess in its outer surface adapted to locate locking means to retain the expandable member within a complementary opening when fitted thereinto.

19. A fastener insert device substantially as hereinbefore described with reference to Figs.1 and 2 or Fig.3 or Figs. 4 and 5 or Figs. 6, 7 or 8 or Figs. 9 and 10 of the accompanying drawings.