On a truck loader, the static position of the work station from which the driver customarily operates the crane controls is not always the best one for loading and unloading. There can be situations where the operator has to work too near to the load for total safety, or others where his or her view may be restricted. Remote control can provide an effective solution.
In the UK, the code of practicepublished by The Association of Lorry Loader Manufacturers & Importers (ALLMI) earlier this year incorporates a guide for crane slingers and a code for signallers*. With remote controls, and properly used in conjunction with this working practice and the relevant international standards, such difficulties can largely be overcome.
As a result, remote control of all operations either by radio or by a thin cable, is becoming an increasingly specified alternative, not only to give improved safety but also to widen the operational range of uses of the truck loader concept.
With the skies around us ever more crowded with radio waves, concern is sometimes expressed about the risk of radio signal collision or other forms of interference causing a stoppage in crane operations and even jeopardising safety.
One way round this is offered by the Swedish manufacturer Scanreco, whose control system overcomes these risks by giving a unique ID-code to every system, which means that only the portable hand control unit can activate its matching receiver on the crane. In addition to this, the system enables the driver to change to one of 11 other radio channels during operation.
The concept of remote control continues to gain acceptance in the truck loader market. A UK haulage operator, AJ Transport of Dereham, Norfolk, has taken delivery of a low-chassis Volvo fitted with a Fassi 420XP loader and radio remote control. AJ specialises in the transportation of often heavy, high value equipment such as computer numerically controlled (CNC) machine tools and electrical control panels.
“We operate at the top end of the market, handling high-value equipment,” says AJ proprietor Andrew Jarvis, “which means we have to use machinery and expertise which matches our high customer expectations. The Volvo and Fassi combination, with radio remote control, means that we can give customers the optimum in truck and loader performance.” Jarvis adds: “The crane also has an extra power facility, which gives us a weight cushion which is particularly useful when customers are not exactly sure of the weight of the machinery they are asking us to handle. This extra power feature gives a clear 5t lifting capacity at full reach of 8m.
“For our type of work, radio control enables us to be totally independent under any site conditions,” he continues. “The operator can move around, with the load, or work up to 200m away from it. CNC tools need careful slinging, so he can adjust and tension the slings as he works. He can also be in position to lower the machine onto skates, remotely manoeuvre the load into a building and then position it inch perfectly. If we are loading up onto a mezzanine or first floor, he can walk up and operate the Fassi entirely from there.” The hand-held radio remote control panel is battery operated and incorporates a radio transmitter and antenna. It works through a receiver on the crane unit, which operates through the system’s Danfoss hydraulic valve block.
Controls include an emergency stop button, radio frequency change and extra power facility, as well as up to eight crane function levers. These levers are protected against accidental operation and are also sprung-loaded to return automatically to the neutral position.
The speed of any loader function is directly proportional to the extent of lever actuation. Additionally, the unit has micro operation by means of which speed can be temporarily stepped down to as little as 20% of normal. This proportional operation enables lifting operations to be performed with precision as well as safety.
