GB2350657A

GB2350657A - Fastener with more than one driving formation

Info

Publication number: GB2350657A
Application number: GB0012783A
Authority: GB
Inventors: Melvin Douglas Jackson
Original assignee: EUROP IND SERVICES Ltd
Current assignee: EUROP IND SERVICES Ltd
Priority date: 1999-05-29
Filing date: 2000-05-26
Publication date: 2000-12-06
Also published as: GB9912546D0; GB0012783D0

Abstract

A fastener has a head which has a recess adapted to receive a driver having either a cross shaped or a hexagonal/arcuate lobed driving formation. Additionally a further recess for receiving a flat blade screw driver may be provided.

Description

2350657 PATENTS ACT 1977 A9822GB-CAS/maj Title: An Improved Fastener

Description of Invention

The present invention relates to an improved fastener and is concerned with a fastener which has a shank part and a head part, the shank part having a helical thread form on the external surface thereof and the head part having a driver engageable formation to enable engagement of the fastener by a driver to cause rotation about the axis of said shank.

For the sake of convenience, such a fastener will hereinafter be referred to as a fastener of the type described.

Such fasteners are well known and many different head formations have been proposed and are in use at present.

The present invention is concerned with a head which has a recess formed therein into which recess a driver is inserted to enable rotation of the fastener.

One form of recess comprises a slot formed diametrically across the head of the fastener, which slot is engaged by a single bladed traditional screwdriver. Another recess comprises a cruciform recess which may be engaged by a cruciform driver such recess being sold under the Registered Trade Marks of PHILIPS or POSIDRIV.

A ftirther recess also much in use is one of modified hexagon form and sold under the Registered Trade Mark TORX The TORX driver has six radial projections which engage in a corresponding shaped recess in the head of a fastener, the recess in the head of the fastener being shallow relative to the depth of recess sold under the PHILIPS or POSIDRI-V Trade Marks.

2 It is known to provide a fastener provided with a recess that will accommodate a cruciform type driver and also a conventional flat screwdriver blade.

It is an object of the present invention to provide an improved fastener.

According to one aspect of the present invention we provide a fastener of the type described having a head and a recess formed in said head capable of receiving and being driven by a driver provided with a cruciform formation and also a hexagonal formation.

Preferably the fastener is drivable by a driver sold under the PHILIPS and/or POSIDRIV Registered Trade Marks and also by a driver sold under the Registered Trade Mark TORX Preferably the arrangement of the recess is such that a pair of a diametrically opposed recesses on the hexagonal formation coincides with approximately diametrically opposed recesses provided in the cruciform receiving formation.

Preferably where the arrangement of the hexagonal recess relative to the crucifonn receiving recess is as mentioned above, the remaining four recesses of the hexagonal receiving formation each intersect a respective land situated between the cruciforin receiving recesses.

Preferably the depth of the recess exceeds that normally provided for a conventional hexagonal recess such as for example a recess sold under the Trade Mark TORX Preferably the depth of the recess exceeds that normally provided for a cruciform receiving recess.

According to a further aspect of the invention the recess may also be capable of receiving a conventional flat blade screwdriver to the extent where the fastener may be driven by, said conventional flat bladed screwdriver.

3 Hitherto it was assumed that the superimposition of a cruciform recess and a hexagonal recess in the same fastener would render both recesses unusable by either a cruciform or hexagonal driver.

Surprisingly however, it has been found that the driving engagement between the driver and the fastener is just as good or in fact improved by the superimposition of the recesses. The precise reasons are not known, however, it is believed that, since the production of fasteners is a mass production operation, in practice with a normal single recess only one or at best two wings of the driver will engage with a surface of the recess at least in a direction where torque may be transmitted to the fastener, and hence the superimposition of the two recesses does nothing to detract from the driving engagement of the driver with the fastener.

It is also thought that the superimposition of the hexagonal recess on the cruciform recess may impart a certain flexibility to the lands between thefour radially extending recesses thus enabling a driver to have increased contact with the driving surfaces of the cruciform recess.

Contact between the hexagonal driver and the hexagonal recess is also enhanced, primarily, it is believed, because the depth of the recess is greater than is conventionally applied for a hexagonal recess, the depth being necessary to accommodate the cruciform driver. As a result there is increased surface area contact between the hexagonal driver and the fastener.

It is also believed that in addition to the reasons mentioned above, the interference to conventional shape of the hexagonal recess caused by the formation of the crucifonn recess also imparts an increased flexibility of the land parts of the headed fastener hence permitting of increased surface contact between the driving faces of the hexagonal driver and the torque receiving faces of the fastener.

4 One example of a fastener in accordance with the present invention will now be described in more detail with reference to the accompanying drawings, wherein:

FIGURE I is a side elevation of the fastener, FIGURE 2 is a plan view of the head of the fastener, FIGURE 3 is a section along the line 3-3 shown in Figure 2.

FIGURE 4 is a side elevation of the fastener shown in the previous drawings modified in the provision of an additional recess.

FIGURE 5 is a section along the line 5-5 shown in Figure 4.

A threaded fastener 10 is shown in Figure 1, the fastener 10 having a shank portion 11 formed with a helical thread form 12 and a head part 13 which is formed with a recess 14 to enable a driver to be inserted into the recess to cause rotation of the fastener 10 about its longitudinal axis 15.

Referring now in addition to Figures 2 and 3, the form of the recess 14 is shown and it can be seen that there is a recess comprising four symmetrically spaced recesses 20, 21, 22, and 23, such a formation being capable of receiving and being driven by a cruciform type driver for example as sold under the Registered Trade Marks PHILIPS and/or POSIDRIV.

The recess 14 also comprises a hexagonal recess located around the axis 14, the hexagonal recess including six radially outwardly projecting wings 30, 31, 32, 33, 34, and 35.

The radially outer edges of two of the wings 30 and 33 can be seen in Figure 3 at 38 and 39 respectively showing that the radially outer edge of the wings 30-35 of the hexagonal recess are substantially parallel to the axis 14 of the fastener.

The depth of the hexagonal recess is very much greater than is conventionally provided with for example a TORX (Registered Trade Mark) recess hence the interference with the normal shape of the hexagonal recess caused by its superimposition on the cruciform recess is compensated by the extra depth to the extent where engagement of the hexagonal driver within the recess is improved compared with a driver having a conventional hexagonal only recess.

It is envisaged that the cruciform recess is of sufficient size to accommodate a conventional blade type screwdriver and as a result the fastener may be driven by three different types of driver.

It may be in certain circumstances particularly where the threaded fastener is of relatively small size that the cruciform recess is not of a sufficient size to accommodate a conventional blade type screw driver and a modification to the recess is shown in figures 4 and 5 in which the opposed wing 20 and 22 of the cruciform recess are shown of elongated form albeit at their diametric extremities the depth of the recess is relatively small. This can be seen in figure 5. The additional recesses shown at 40 and 41 permit the fastener to be driven more easily by a conventional blade type screw driver.

The multi recess fastener as described above provides a significant improvement in that it can be used for example alongside fasteners that for one reason or another are provided only with a cruciform recess or a hexagonal recess, without the operator having to change either the head part of a driving machine, the driving machine itself, or where applicable, a hand operated driver to insert the fastener.

Surprisingly also the engagement of either a hexagonal driver or a cruciform driver with the universal recess provided in the fastener of the present invention has been found to be enhanced compared with a normal single hexagonal recess or normal single cruciform recess which is quite the opposite to what would perhaps be expected.

It has also been found that the recess can be formed by a single punch thus obviating the need for two punching operations.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in

6 terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

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Claims

1. A fastener comprising a shank part and a head par the shank part having a helical thread form on the external surface thereof and the head part having a driver engageable formation to enable engagement of the fastener by a driver to cause rotation about the axis of said shank wherein said head part has a driver engageable formation capable of receiving and being driven by a driver provided with a cruciform formation and also a driver provided with a hexagonal formation.

2. A fastener as claimed in claim 1 wherein said recess is such that a pair of diametrically opposed recesses on the hexagonal formation coincides with approximately diametrically opposed recesses provided in the cruciform receiving formation.

3. A fastener as claimed in claim 2 wherein the remaining four recesses of the hexagonal receiving formation each intersect a respective land situated between the cruciform receiving recesses.

4. A fastener as claimed in any one of the preceding claims wherein the depth of the recess capable of receiving and driven by a driver provided with a hexagonal formation is deeper than is normally provided.

5. A fastener as claimed in any one of the preceding claims wherein the depth of the recess adapted to receive and be driven by a driver provided with a cruciform formation is greater than that that is normally provided.

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6. A fastener as claimed in any one the preceding claims wherein the cruciform recess is adapted to receive and be driven by a driver sold under the PHILIPS and/or POSIDRIV registered trade mark.

7. A fastener as claimed in any one of the preceding claims wherein the hexagonal formafion is adapted to receive and be driven by a driver sold under the TORX registered trade mark.

8. A fastener as claimed in any one of the preceding claims wherein a further recess is provided capable of receiving and being driven by a conventional flat blade screw driver.

9. A fastener as claimed in claim 8 wherein the further recess is aligned with diametrically opposed wings of the cruciform recess.

10. A fastener as claimed in claim 9 wherein said further recess does not extend completely across the head of the fastener.

It. A fastener substantially as hereinbefore described with reference to and as illustrated in figures I to 3 of the accompanying drawings.

12. A fastener substantially as hereinbefore described with reference to and as illustrated in figures 4 and 5 of the accompanying drawings.

13. A fastener including any novel feature or novel combination of features as described herein and/or illustrated in the accompanying drawings.