Unique Uni-Screw, designed and manufactured in the UK, is the most significant development in screw fixing for decades

Citation

(2001), "Unique Uni-Screw, designed and manufactured in the UK, is the most significant development in screw fixing for decades", Assembly Automation, Vol. 21 No. 2. https://doi.org/10.1108/aa.2001.03321baf.004

Unique Uni-Screw, designed and manufactured in the UK, is the most significant development in screw fixing for decades

Unique Uni-Screw, designed and manufactured in the UK, is the most significant development in screw fixing for decades

Keywords Drivers, Fasteners

Once a decade, an invention comes along that makes everyone totally revise the way that they think about an accepted form of technology. In the 1990s it was the Dyson vacuum cleaner. In the first decade of the twenty-first century it is set to be Uni-Screw, a revolutionary new screw and driver fastening system which substantially reduces tooling costs, improves assembly productivity and eliminates cam-out.

Uni-Screw was developed by engineers in Sheffield and is manufactured in the UK by Birmingham-based Forward Engineering. Uni-Screw is a direct replacement for Slotted, Phillips™, Pozi-Drive™ and Torx™ screws and offers significant advantages over these fixing media. As such it represents the most powerful development in screw fixing for decades.

Uni-Screw's unique design means one driver for screw size M2-M12

Uniquely, Uni-Screw uses the same driver for all sizes and so does not require any tool changes for screws between M2 and M12. (see Figure 2 and Plate 1). This is achieved because the Uni-Screw castellated driver locates tightly into the screw head, providing multiple drive surfaces, no matter what the size. For the smallest screw sizes, only the smallest of the three driver tiers is used. As screws increase in size, either two or three tiers are used for maximum torque.

Figure 2 Uni-Screw compared with other screw types

Plate 1 Just one drive is needed for screws from M2 to M12 and screws are available with any head and thread configuration

The single driver feature has considerable positive cost implications for all users of screw fasteners. In industrial assembly environments tooling costs are reduced and production time is saved, because the need to change screwdriver bits to accommodate different sizes of screws is removed. The same is true for products which, because of their complexity, need to be hand-assembled. The assembler will, in the main, require just one screwdriver bit, reducing down-time, the costs of the bits themselves and the cost of replacing drivers that inevitably get misplaced.

Cam-out eliminated

Uni-Screw's unique design also overcomes "cam-out", a major problem describing the tendency of conventional tapered drivers to force themselves out of screw heads when they are rotated. With Uni-Screw both screw and driver surfaces are precisely aligned with the driver axis, so there is no tendency for the driver to disengage under load or "cam-out'. In addition, only minimal end-load ever need be applied, thereby minimising operator fatigue.

Design provides exceptional directional stability

The multiple concentric hexagonal driving surfaces, a unique feature of the Uni-Screw design, offer exceptional directional stability and are able to define a direction in space with an accuracy better than three degrees. There are two main benefits. First, on assembly lines torque can be applied controllably and with reduced risk of stripping the screw head recess. Second, Uni-Screw provides the ideal solution in applications where there is poor access or no direct line of sight to the fastener location.

Secure location solves problems in sensitive electronic assembly

Complementing Uni-Screw's exceptional directional stability is the system's designed ability to locate the driver so firmly within the screw that an electric screwdriver can be released horizontally with the screw supporting its weight. This feature allows the Uni-Screw system to be used with confidence in sensitive electronic equipment environments, because the screw is held in place without magnetism. This has the added benefit that screw fastening can be undertaken by one-handed operators, opening up improved opportunities for disabled people in light engineering employment and in domestic DIY.

Tamper resistance can be tailored to specific needs

Uni-Screw's unique design also satisfies the increasing demands for a type of fastener that is tamper resistant. The intricate nature of many types of control equipment, used in industrial processes, computers, printers and other electrical equipment, means increasingly that only trained and authorised personnel are able to access their internal electronics or mechanics. The standard Uni-Screw system, with its three precisely aligned hexagonal drive surfaces, addresses this situation by providing a moderate degree of protection against tampering (see Plate 2).

Plate 2 Uni-Screw's three-tier hexagonal driving head locates firmly into screw heads

For greater security, a matching screw and driver system can be tailored to meet specific customer needs. With bespoke designs the drive surfaces can be square, pentagonal, heptagonal or a combination of these shapes, thereby precluding the use of hex keys entirely. Configuring the surfaces in this way means that the screw recesses can be also made to appear circular to the naked eye, which has the effect of "camouflaging" them offering very high levels of tamper resistance.

Enquiries: Malcolm Clarke, Forward Engineering Products Ltd, Unit 12, St Andrews industrial estate, Sydney Road, Small Heath, Birmingham B9 4QB, UK. Tel: +44 (0)121 771 4345; Fax: +44 (0)121 771 4244; e-mail: forward-eng-products@lineone.net; Website: http://www.uni-screw.com