Contactless rotary pull switch

Abstract

A contactless rotary pull switch includes a switch knob assembly rotatable about an axis to a plurality of rotational positions and actuatable to at least one pull position, with the switch knob assembly including a knob element and a rotational shaft fixedly coupled thereto. A rotational magnet is coupled to the rotational shaft so as to rotate therewith, and at least one pull magnet is positioned separately from the rotational magnet. A rotational sensor senses a magnetic field generated by the rotational magnet to identify a rotational position of the switch knob assembly and at least one pull sensor senses a magnetic field generated by the pull magnet(s) to identify a pull position of the switch knob assembly. A rotatable arm member selectively enables/inhibits sensing of the magnetic field generated by the pull magnet(s) by the at pull sensor(s), to identify distinct pull positions of the switch knob assembly.

Description

BACKGROUND OF THE INVENTION[0001]Embodiments of the invention relate generally to rotary pull switches and, more particularly, to contactless rotary pull switches such as might be used as lighting switches for a motor vehicle.[0002]In specialty vehicle markets—such as heavy trucks, agricultural equipment, and construction equipment, for example—various types of electrical switches are used as control switches for a variety of applications, including general vehicle features / applications (e.g., switching the motor vehicle lighting, the windshield wipers, the rear windshield heating, the cruise control functions, etc., on and off) and critical or safety related vehicle features / applications (e.g., power take-off (PTO) switches, “e-stop” type switches, etc.). With respect to a vehicle lighting switch in particular, a typical vehicle lighting switch includes a rotary control having at least three positions: all lights (parking lamps and headlamps) OFF, parking lamps ON, and all lights O...

AI Technical Summary

Benefits of technology

[0006]Embodiments of the present invention provide a contactless rotary pull switch that provides for robust sensing of both the rotational position and the pull position of the switch.

Problems solved by technology

With respect to contactless rotary pull switches that are utilized in vehicle lighting switches or in switches for other applications, it is recognized that existing designs of such switches can limit the performance thereof.

However, these variations in the magnetic field strength may not be great enough to discern a distinct switching position.

As such, mechanisms such as optical fibers or light pipes are necessary for transmitting light from the LEDs to the symbols on the face of the switch, thereby increasing the cost and complexity of the switch.

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