A magnetic tether switch for equipment or vehicles is described. The magnetic tether switch may include a base having a first magnetic assembly. The first magnetic assembly may include a magnet and a first magnetic flux return component, or multiple magnets with reversed polarization directions. The magnetic tether switch may include a cap including a second magnetic assembly. The second magnetic assembly may include a magnet and a magnetic flux return component, or multiple magnets with reversed polarization directions. Alternatively, the second magnetic assembly may be composed of a ferrous material. The base may include a circuit with multiple contacts, where attaching the cap to the base may connect or disconnect the contacts to each other by moving the magnet within the base by magnetic attraction from the cap.

In one aspect, an apparatus for use in a wellbore is disclosed that in one non-limiting embodiment includes a string for placement in the wellbore and a switch on an outside of the string, wherein the switch includes a plurality of magnetic elements that provide a continuous electrical when the plurality of magnetic elements are aligned by an externally applied magnetic field. In one embodiment, the switch includes a channel that houses the plurality of magnetic elements that remain unaligned until the magnetic elements are aligned by the externally applied magnetic field.

A keyswitch structure includes a base plate, a keycap, a scissors support connecting the keycap and the base plate, a linking support rotatably disposed on the base plate, a movable part movably disposed relative to the base plate, and a magnetic part on the movable part. The linking support includes a magnetic portion and a driving portion. The magnetic part and the magnetic portion produce a magnetic attraction force therebetween. When the movable part is located at a first position, the magnetic part is located under the magnetic portion, and the magnetic attraction force drives the keycap through the linking support to move away relative to the base plate. When the movable part moves from the first position to a second position, the magnetic part moves away relative to the magnetic portion, so that the magnetic attraction force decreases so as to make the keycap move toward the base plate.

A magnetic tether switch for equipment or vehicles is described. The magnetic tether switch may include a base having a first magnetic assembly. The first magnetic assembly may include a magnet and a first magnetic flux return component, or multiple magnets with reversed polarization directions. The magnetic tether switch may include a cap including a second magnetic assembly. The second magnetic assembly may include a magnet and a magnetic flux return component, or multiple magnets with reversed polarization directions. Alternatively, the second magnetic assembly may be composed of a ferrous material. The base may include a circuit with multiple contacts, where attaching the cap to the base may connect or disconnect the contacts to each other by moving the magnet within the base by magnetic attraction from the cap.

A magnet reed switch assembly. The magnetic reed switch assembly includes a reed switch having a body and a pair of electrical contacts disposed in the body. A ring magnet has a bore, and a portion of the body of the reed switch is disposed within the bore, with the ring magnet positioned close to the pair of electrical contacts. The ring magnet is movable along the axis of the body between a first position and a second position. A plunger includes a proximal end coupled to the ring magnet and a distal end having a sensing magnet. When a ferrous target is disposed near the sensing magnet, the plunger moves toward the ferrous target causing the ring magnet to move from the first position to the second position, and the reed switch to move from an open state to a closed state.

A security switch for detecting an actuator comprises a magnetic field source, a magnetically susceptible object, and a circuit. The magnetic field source is configured to produce a magnetic field gradient. The magnetically susceptible object is suspended at a first position at least in part due to the magnetic field gradient and shiftable to a second position when the actuator affects the magnetic field gradient. The circuit is configured to detect when the object is in the second position.

An improved magnetic switch assembly (16) has a housing (24), a first electrode (40) positioned within the housing (24), a second electrode (42), and a magnetically movable component (48) located within the housing (24) and shiftable between a first position in simultaneous contact with electrodes (40, 42), and a second position out of such simultaneous contact. The electrode (40) has a radially enlarged contact section (44, 58) adjacent the free end thereof which prevents hangup or sticking of component (48) in the first position.

A magnet reed switch assembly. The magnetic reed switch assembly includes a reed switch having a body and a pair of electrical contacts disposed in the body. A ring magnet has a bore, and a portion of the body of the reed switch is disposed within the bore, with the ring magnet positioned close to the pair of electrical contacts. The ring magnet is movable along the axis of the body between a first position and a second position. A plunger includes a proximal end coupled to the ring magnet and a distal end having a sensing magnet. When a ferrous target is disposed near the sensing magnet, the plunger moves toward the ferrous target causing the ring magnet to move from the first position to the second position, and the reed switch to move from an open state to a closed state.

A keyswitch structure includes a base plate, a keycap, a scissors support connecting the keycap and the base plate, a linking support rotatably disposed on the base plate, a movable part movably disposed relative to the base plate, and a magnetic part on the movable part. The linking support includes a magnetic portion and a driving portion. The magnetic part and the magnetic portion produce a magnetic attraction force therebetween. When the movable part is located at a first position, the magnetic part is located under the magnetic portion, and the magnetic attraction force drives the keycap through the linking support to move away relative to the base plate. When the movable part moves from the first position to a second position, the magnetic part moves away relative to the magnetic portion, so that the magnetic attraction force decreases so as to make the keycap move toward the base plate.

A target magnet mechanism for a proximity switch. The target magnet mechanism includes a plurality of magnets disposed in an alternating magnetic pole configuration forming a narrowed, polarity reversing magnetic field. A center magnet has a magnetic polarity opposite the magnetic polarity of a sensing magnet of the proximity switch. A flanking magnet includes a magnetic polarity opposite the magnetic polarity of the center magnet and the same as the sensing magnet. So configured, the plurality of magnets trigger the proximity switch to an activated state by pulling on a magnetic field of the proximity switch via the opposed polarity of the center magnet and the sensing magnet. In addition, the plurality of magnets release the proximity switch back to an unactivated state by pushing on the magnetic field of the proximity switch via the same polarity of the flanking magnet and the sensing magnet.