Magnetic limit switches allow you to set precise travel limits and stops on screw jacks and actuators. They are also ideal in any application where rotary motion of a machine component can be used to indicate linear motion of another part.
Magnetic limit switches are sensors with reed contact and are fitted with a clamp on the aluminium, or other non-magnetic metal, protective tube T. They are activated by the magnetic field generated by a magnetic ring fitted on the traveling ball screw end.
In case the screw jack is not stopped after the sensor activation, without magnetic field the sensor restores the original state. In case the limit switches are used to stop the screw jack, we recommend to provide an electric connection in order to latch the signal and prevent the screw jack from moving again in the same direction.
Screw jacks with magnetic limit switches are supplied with two sensors for the ball screw extreme positions. On request, extra switches for inter-mediate positions can be supplied.
The position of the sensors along the tube is adjustable.
The accuracy of the stopping position depends on speed, the size and direction of the load, motor characteristics, brakes if present and control circuitry.For advice on a specific application speak to our engineers.