Machine guarding systems are becoming much more refined and widespread as we all deal with the increasingly sophisticated implications of social and technical trends in industry, from manufacturing to packaging and processing. All such trends come with their own developing technical applications and legislation to match. Consequently, accessory and component manufacturers like Elesa have created ranges of products specifically designed to make the task easier for builders and installers of everything from equipment cages through access panels to the associated control cabinets.
Availability of simple and inexpensive modular systems is a major factor in production of many machine guarding systems and, coupled with a range of compatible accessories developed to meet regulations, is important both for the effectiveness of the guarding and for cost effectiveness of its assembly. Building on the basis of industry-standard tubular frame systems, the Elesa range enables complete frame assembly with associated panel fixing, panel hinging, door fabrication, door hinging, locking and interlocking to ensure quick, simple, robust and reliable installations.
Fundamental to many guarding systems is the need for square tube connectors; Elesa's STC range comprises zinc-plated steel reinforced and stainless steel-reinforced plastic versions which suit 20mm, 25mm and 30mm square tubes and eliminate the need for welding.
Naturally the completed frame requires both fixed and moveable panels in materials from wire mesh to polycarbonate; where a fixed installation is required, then PC Panel Support Clamps are convenient as they offer a smart and robust method for the installation of guard panels up to 8mm thick without the need to drill. These clamps are fully retained assemblies which fix by machine screw to the guard frame and are compliant with the Machine Directive 2006/42/CE Part 1, 4.2 which specifies that: "The Fixing Systems of guards must remain attached to the guards or to the machinery when the guards are removed".
Panel installation with PC Panel Support Clamps requires only that the correct spacer be fitted to match the relevant panel thickness and then the hex keyed screw (M6) be tightened up - the positive grip characteristics of the clamp plus its method of fixing then ensure a secure fixing of the guard panel.
Where an opening panel is needed, then quick access can be readily achieved by the use of Elesa's Ball Shaped Door Lock, typically applied on sliding access doors or on window-style ventilation panels, either on its own or with locking handle, or with safety switch-enabled hinges, such as the Elesa CFS range. Single screw fitment for the ball and for the spring clamp elements facilitates quick and positive location, while spacers of 5mm, 10mm and 15mm allow the installation to compensate for differences of thickness between the door and the frame, so ensuring a proper fit and finish.
A feature often required is that of quick operation - possibly while wearing gloves - and in this case the ESC door lock handle provides a design which is ergonomic, so enabling both rapid and safe operation of equipment.
Machine guarding of electrical/electronic control cabinets naturally implies door hinging with automatic safety cut-off switches, which are now available to be installed with the cut-off switch as an integral facility of the hinge itself. A good example is the new Elesa CFSW IP67 180 degree hinge, which has its own built-in multiple safety switch, so that in the event of accidental opening of a control cabinet door, machine panel or safety door, it automatically shuts off the power, so protecting the operators of machinery and production equipment. The CFSW is paired with its equivalent mechanical hinge, the CFMW so creating a tough, safe installation.
The CFSW is double insulated and approved AC15 (IEC 60947-5-1) and DC13 (IEC 60947-5-2) for usage up to 400V-4A (AC15); it is available with different combinations of contacts with positive opening (2NO+2NC, 1NO+3NC etc.). These robust units are tested to over 1 million operating cycles, are totally tamper-proof, and may be quickly and easily installed.
Standard connectivity is with 8 pole connector or 8 core cable in 2m or 5m lengths; 180 degree opening is normal but other operating angles may be specified. Operational configurations include NC with positive opening, for removal/cutting off of power; NO for operation of positive alarms etc.; NC + NO versions combined for achievement of both functions simultaneously.
CFSQ and CFS hinge operation is adjustable in 15 ° increments from a minimum of 5 degrees up to a maximum of 180 degrees. The 5 degree angle is appropriate for standard (small) doors, but is adjustable prior to installation down to 1 degree for large doors, so as to minimise opening aperture.
The development of this integral hinge/switch technology is a significant benefit in production of machine guards since it is easy to install mechanically and electrically while being compatible with most common aluminium profiles or steel tube systems. The Elesa website provides extensive user guidance for installation, configuration and operation. Further information regarding Elesa machine guarding components may be found at www.elesanow.co.uk/.