Castors
AssigneeCastor Technology Ltd.
InventorAlan Foster
Life of this patent
Estimating the term…
Abstract
A support structure for a castor, a castor provided with such a support-structure, and a castored trolley is described. The support structure comprises a first member 5, a second member 3 that is rotatable with respect to the first member about a pivot axis, and magnetic means 21, 23, 61, 63 that is operable up to a certain torque to restrain movement of the rotatable member from one angular position with respect to the first member. Preferably the magnetic means comprises at least one hair of magnetically co-operable components. Preferably one component of the at least one pair of components is a permanent magnet. In another angular positions without registration of the first and second members free rotation is possible unless and until re-registration occurs.
Claims23
A support structure for a castor comprising a first member, a second member that is rotatable with respect to the first member about a pivot axis, and magnetic means that is operable up to a certain torque to restrain movement of the second member from one angular position with respect to the first member, wherein said magnetic means comprises a first magnet associated with the first member and a second magnet associated with the second member, said first magnet being coaxially aligned with respect to said second magnet wherein said first magnet and said second magnet are disposed to have confronting faces that are spaced apart to define an air gap therebetween, and means is provided to adjust the spacing between confronting faces of said first magnet and said second magnet.
A support structure for a castor, comprising:
- (i) first and second plates located in co-axial, spaced apart relationship so as to provide mutually facing surfaces,
- (ii) bearing means located between the plates whereby one plate is rotatable with respect to the other plate, and
- (iii) one component of at least one pair of co-operable components being mounted on each plate, at least one of which pair of components is a permanent magnet adapted, in one angular position of the rotary plate with respect to the non-rotary plate, to be brought into registration with a relatively small air gap between confronting adjacent surfaces of the two co-operable components to create a magnetic flux that, up to a certain torque restrains rotation, and in other angular positions without registration permits free rotation unless and until re-registration occurs wherein said components of said at least one pair of co-operable components mounted on each plate are co-axially aligned with respect to one another and means is provided to adjust the spacing between confronting surfaces of said two co-operable components.
Dependencies are inferred from the claim text.