Magnetically actuated pressure sensitive suspension position sensor
An elongated pressure sensitive potentiometer is disposed alongside and generally parallel to a reciprocating suspension component, such as a shock absorber, and between a steel track and a rolling or static magnet. The track and contained potentiometer extend from a mount at or near the top of a cylinder of the shock absorber to a point beyond the magnet when the shock absorber is in an uncompressed state. The mount couples the track to the shaft, parallel to and spaced apart from the shaft. Magnet attraction of the track compresses the potentiometer between the track and magnet.
1. A magnetically actuated pressure sensitive sensor comprising
a track, the track having a track length and track width, the track including a ferromagnetic web;
a potentiometer attached to the web of the track, the potentiometer being a pressure sensitive potentiometer having a length that is not greater than the length of the track, and having width that is not greater than the width of the track;
a magnet having a diameter; and
a holder adjacent to the track, the holder including an axle, the magnet having an axis of rotation and the axle extending through the axis of rotation, and the magnet being capable of rotation about the axle, the track being movable relative to the holder along a reciprocating axis orthogonal to the axis of rotation, and the holder supporting the magnet in abutting relationship to the potentiometer attached to the web of the track;
the magnet attracting the ferromagnetic web of the track with force effective for actuating the potentiometer, the force compressing the potentiometer between the magnet and the web of the track.
2. The magnetically actuated pressure sensitive sensor of claim 1 , the magnet having a shape from the group consisting of a cylinder and a sphere.
3. The magnetically actuated pressure sensitive sensor of claim 1 , the magnet being a permanent magnet.
4. The magnetically actuated pressure sensitive sensor of claim 1 , the track being a cantilever structure and deflectable towards the magnet.
5. The magnetically actuated pressure sensitive sensor of claim 1 , the track including a C-cross section shape, including a pair of opposed flanges extending from the web, and a pair of lips extending towards each other from the web, and a space defined between the lips, the space having a width, and the web, flanges and lips defining a cavity, the cavity having a width and depth.
6. The magnetically actuated pressure sensitive sensor of claim 5 , the holder including a neck having a width less than the width of the space between the lips of the track, the neck extending through the space between the lips.
7. The magnetically actuated pressure sensitive sensor of claim 6 , the holder including a head attached to the neck, the cavity containing the head, the head having a width greater than the width of the space between the lips, and the axle being operably coupled to the head of the holder.
8. The magnetically actuated pressure sensitive sensor of claim 7 , the holder including a base, the neck disposed between the base and the head.
9. The magnetically actuated pressure sensitive sensor of claim 8 , further comprising an attachment securing the holder to a first structure.
10. The magnetically actuated pressure sensitive sensor of claim 9 , the attachment comprising a strap.
11. The magnetically actuated pressure sensitive sensor of claim 9 , a bracket securing the track to a second structure.
12. The magnetically actuated pressure sensitive sensor of claim 11 , the first structure and second structure being concentric and the second structure being movable linearly relative to the first structure along a path, the path being parallel to the track, movement of the second structure relative to the first structures causing equal movement of the track relative to the magnet.
13. The magnetically actuated pressure sensitive sensor of claim 12 , the first structure comprising a cylinder of a shock absorber and the second structure comprising a shaft of the shock absorber, the shaft of the shock absorber being movable telescopically relative to the cylinder of the shock absorber.
14. The magnetically actuated pressure sensitive sensor of claim 13 , the head of the holder including a slot having a width, the magnet having a width, the width of the magnet being less than the slot, and the width of the slot being less than the width of the potentiometer.
15. The magnetically actuated pressure sensitive sensor of claim 14 , the axle extending through the slot and the slot receiving a portion of the magnet.
16. The magnetically actuated pressure sensitive sensor of claim 13 , the shock absorber attached to a fork of a two-wheel vehicle.
17. The magnetically actuated pressure sensitive sensor of claim 16 , the two-wheel vehicle comprising a vehicle from the group consisting of a bicycle and a motorcycle.
18. The magnetically actuated pressure sensitive sensor of claim 1 , further comprising a data logger operably coupled to the potentiometer.
19. The magnetically actuated pressure sensitive sensor of claim 18 , further comprising a smartphone operably coupled to the data logger.
20. A bicycle equipped with a magnetically actuated pressure sensitive sensor, the bicycle having a fork with a pair of shock absorbers, the magnetically actuated pressure sensitive sensor comprising
a track, the track having a track length and track width, the track including a ferromagnetic web, the track including a C-cross section shape, including a pair of opposed flanges extending from the web, and a pair of lips extending towards each other from the web, and a space defined between the lips, the space having a width, and the web, flanges and lips defining a cavity, the cavity having a width and depth;
a potentiometer attached to the web of the track, the potentiometer being a pressure sensitive potentiometer having a length that is not greater than the length of the track, and having width that is not greater than the width of the track;
a magnet having a diameter and a shape from the group consisting of a cylinder and a sphere, the magnet being a permanent magnet; and
a holder adjacent to the track, the holder including an axle, the magnet having an axis of rotation and the axle extending through the axis of rotation, and the magnet being capable of rotation about the axle, the track being movable relative to the holder along a reciprocating axis orthogonal to the axis of rotation, and the holder supporting the magnet in abutting relationship to the potentiometer attached to the web of the track, the holder including a neck having a width less than the width of the space between the lips of the track, the neck extending through the space between the lips, the holder including a head attached to the neck, the cavity containing the head, the head having a width greater than the width of the space between the lips, and the axle being operably coupled to the head of the holder, the holder including a base, the neck disposed between the base and the head, the head of the holder including a slot having a width, the magnet having a width, the width of the magnet being less than the slot, and the width of the slot being less than the width of the potentiometer, the axle extending through the slot and the slot receiving a portion of the magnet;
the magnet attracting the ferromagnetic web of the track with force effective for actuating the potentiometer, the force compressing the potentiometer between the magnet and the web of the track, the track being a cantilever structure and deflectable towards the magnet;
an attachment securing the holder to a first component of one of the pair of shock absorbers;
a bracket securing the track to a second component of the one of the pair of shock absorber, the first component and second component being concentric and the second component being movable linearly relative to the first component along a path, the path being parallel to the track, movement of the second component relative to the first component causing equal movement of the track relative to the magnet, one of the first component and the second component comprising a cylinder of the shock absorber and the other of the first component and the second component comprising a shaft of the shock absorber, the shaft of the shock absorber being movable telescopically relative to the cylinder of the shock absorber.