Hinge Switch for Machine Safety from Banner Engineering

Banner Engineering Corp. has introduced the SI-HG63 Series Hinge Safety Interlock Switches for safeguarding of hazards. SI-HG63 hinge switches are used in place of the standard hinges on swinging guards, gates or doors. They offer two normally closed safety contacts and one normally open auxiliary contact for greater application flexibility. When the SI-HG63 hinge switch is activated, these normally closed safety contacts are forced open by a nonresilient mechanical means (not reliant on springs), interrupting the electrical circuit and sending a stop signal to the machine control. SI-HG63 hinge switches are also repositionable, with a safety switching point that is easily adjustable (±1.5°) throughout the hinge's full 0-270° range of motion.

Banner's SI-HG63 hinge switches are built to withstand harsh plant environments, with each safety switch body integrated into a highly robust PBT housing and integrated on to a stainless steel hinge. They are rated IEC IP67 and deliver superior performance and improved protection against defeat over actuator-style safety switches. Each hinge can support an axial and radial load of 1200 N (approximately 120 kg). In addition to in-line QD and "out-the-back" right-angle QD models, right-side and left-side hinges are available, which can be converted to operate from the opposite side when needed. List price for SI-HG63 hinge switches start at $159 each.

"Safeguarding a hazard with a guard, gate or door that is mounted on a hinge is one of the most common safety applications and also can be one of the most difficult to solve," said Mike Carlson, technical manager for Banner's safety products. "Typically, this type of application would use a keyed-actuator style of safety switch, but because the door or guard may sag or otherwise gets deformed, alignment problems with the switch and the actuator can arise. This usually results in damage to the switch and machine downtime," explains Carlson. "The SI-HG63 hinge switches do not have this problem and are a rugged, reliable solution that is very difficult to defeat."

Carlson adds, "When properly interfaced, they prevent cycle initiation or send a stop signal if the guard is opened, halting the hazardous motion. Depending on the number of switches on a guard and the means of interfacing, such as with a safety module, the SI-HG63 hinge switch can meet safety category 2, 3, or 4 [ISO 13849-1] and U.S. control reliability requirements."