Patent ID: 7679479

Claim:
An adjustable magnetic switch for controlling an electric circuit mountable to first and second support members, one of which members is movable, the switch comprising: a control arranged to be secured to the first support member having at least one magnetizable contact means arranged for movement between a setting condition and a non-setting condition to control electric current to the electric circuit, the at least one contact means defining a contact axis, a magnetic actuator secured to the second support member; and an adjustable member secured to the movable one of said members; the magnetic actuator exhibiting a magnetic field comprising first and second magnetic field portions wherein the first field portion comprises an elongated magnetic field of a given polarity in a desired direction defining a substantially continuous elongated magnetic actuation field portion of an extent of a given magnitude and elongated in a first direction that is substantially greater than the extent of the second magnetic field portion of the given polarity in a second direction transverse to the first direction, the first magnetic actuation field portion being normal to the contact axis for moving the at least one contact means between the setting condition and the non-setting condition, the adjustable member including an operative control member to adjustably control the relative direction of the first magnetic actuation field portion to the contact means axis, so that the movable one support member moves relative to the fixed support member a greater distance than is obtainable using a magnetic field corresponding to the extent of the second field portion, without a change in the setting or non-setting condition of the at least one contact means.