Hydraulic power unfolds for the big view

New challenges in hydraulics are mounted by very large outdoor television screens that are installed in large trucks, and then unfolded and extended to provide visibility for spectators who may be distant from crucial parts of an event. Ever larger - 100 square metre designs are being planned – they nonetheless need to be easily portable and deployable, if transport and setup times and costs are not to be excessive. Penny Hydraulics based in Derbyshire, has recently designed and built the working mechanism of three very large, truck-mounted outdoor screens for Vipex, which is based in neighbouring Nottinghamshire. Penny Hydraulics specialises in bespoke hydraulics, while Vipex specialises in equally bespoke specialist vehicles and trailers. Robin Penny, managing director of Penny Hydraulics says that, as well as having to unfold, the screens must be able to be raised, rotated through 360°C and not tip the trailer over if the wind blows strongly. The latter is accomplished by a system of extending supports, but the design is further complicated by the trailer incorporating a stage that unfolds when the screen unfolds and extends. The rotation is accomplished by a hydraulic motor and gears, but the screen raising and support extending system combines hydraulic rams, some of which are 3m long and 150mm in diameter, with box section inside box section telescopic slides, so there is no side loading on the rams. A particular challenge is posed by the need to run hoses and rams inside the box sections in the limited space available. Penny told us that the systems include 34 functions, which are all operated by a wireless remote control, so the operator is well clear of everything as it unfolds and erects, and can also observe that everything is happening correctly. The systems are designed to be completely independent of external power supplies, and can be run for up to a week on the diesel stored on the vehicle. This is necessary because the screens are often used in fairly remote locations – a most recent usage being a display at the finish of the Round the World Clipper Race. With each screen having to be bigger and better than its predecessor but go on the same sized truck, Penny commented that, "The next one is going to be a real challenge". However, innovating to solve challenges is what the business is all about. A recent contract has been to design folding platforms for the extra cameras that Sky Television intends to use for its new 3D service, which was scheduled to be launched on October 1st. All Premier League clubs are to have these, but the clubs want them to fold up so that, when not in use, they can be folded up to reveal extra advertising space. The company makes its own hydraulic rams, because they are mostly non standard sizes, including 1m long 300mm diameter rams for up to 140 tonne presses for fork lift truck tyres. It also makes a range of small cranes and platform lifts for commercial vehicles, pub cellar lifts and various other products for customers that include what's left of the UK mining industries, but bespoke products is its real speciality. A recent contract relates to servicing scissor lift based mobile control towers for airfields in Afghanistan, so they can be lowered in between operations to make them less of a target for our adversaries. Pointers * Company specialises in bespoke designs involving a real challenge, such as ever larger unfolding and self erecting, truck mounted, outdoor, ultra large sized television screens * This involves its making its own hydraulic cylinders, since most of the bespoke designs require non standard sizes, as well as sophisticated control systems