Exercise resistance device with magnets
An exercise resistance device for use in an exercise apparatus includes a rotatable shaft and an impeller rotatable within a fluid filled sealed chamber. A rotating member is joined for rotation with the rotatable shaft. The rotating member is external to the sealed chamber and is magnetically coupled to the impeller.
1. A bicycle exercise resistance device comprising:
a support member;
a roller rotatable on the support member, the roller being adapted to engage a tire of a bicycle;
an impeller rotatable within a fluid filled sealed chamber;
a rotating member joined for rotation with the roller, the rotating member being external to the sealed chamber and magnetically coupled to the impeller;
at least one first magnet provided on the impeller and at least one second magnet provided on the rotating member; and
a housing forming the sealed chamber, the housing including a bowl portion joined to a thin plate member that faces the rotating member and is disposed between the first and second magnets, the bowl portion and the thin plate member having a stationary seal formed therebetween.
2. The bicycle exercise resistance device of claim 1 wherein the seal comprises an o-ring.
3. The bicycle exercise resistance device of claim 1 and further comprising stationary vanes mounted to the housing and disposed in the sealed chamber.
4. The bicycle exercise resistance device of claim 3 wherein the stationary vanes are provided on the bowl portion and wherein the impeller is rotatably mounted to the bowl portion.
5. The bicycle exercise resistance device of claim 1 , wherein the thin plate member is constructed of a non-magnetic material.
6. The bicycle exercise resistance device of claim 5 , wherein the non-magnetic material comprises a ceramic material.
7. The exercise resistance device of claim 1 , wherein the distance between the first and second magnets is approximately 0.120 inches.
8. The bicycle exercise resistance device of claim 7 , wherein the thin plate member has a thickness of approximately 0.060 inches.
9. The exercise resistance device of claim 8 , wherein the thin plate member is positioned approximately 0.030 inches from each of the first and second magnets.
10. A bicycle exercise resistance device comprising:
a support member;
a roller rotatable on the support member, the roller being adapted to engage a tire of a bicycle;
an impeller rotatable within a fluid filled sealed chamber, wherein the impeller includes a high-permeability magnetic material and at least one magnet; and
a rotating member joined for rotation with the rotatable shaft, the rotating member being external to the sealed chamber and magnetically coupled to the impeller.
11. The bicycle exercise resistance device of claim 10 wherein the high-permeability magnetic material portion comprises a plate facing the rotating member, wherein the magnet is joined to the plate between the plate and the rotating member.
12. The bicycle exercise resistance device of claim 10 wherein the rotating member includes a second high-permeability magnetic material portion and at least one magnet.
13. The bicycle exercise resistance device of claim 10 wherein the second high-permeability magnetic material portion comprises a plate facing the impeller, wherein the magnet is joined to the plate between the plate and the impeller.