Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
250 words
In a locking mechanism for sets of castors of the kind, in which the castor wheel is journalled in a fork being able to revolve on a tubular wheel carrier, the improvement which consists in each of the tubular wheel carriers enclosing a tubular part of a locking member, slidingly fitting into the tubular wheel carrier, said tubular part of the locking member being able to move up and down, but not to revolve in said tubular part of the wheel carrier, the tubular part of the locking member carrying a brake flange at the underside which can be brought to bear against the wear surface of the castor wheel in one extreme position of the movement of the locking member, and against the wheel fork in the other extreme position to prevent the latter from revolving, the locking members being pairwise served by means of a lever system being designed as a toggle press, wherein the lever system acting on a pair of castors comprises a short, nearly vertical lever at each castor wheel, one end of said lever being pivotable on a pivot horizontally mounted in the tubular part of the locking member, a connecting rod between the other ends of said short vertical levers and pivotably connected to said ends of the short levers being movable in its longitudinal direction, and a roller being mounted adjacent each of the thus established toggle links, said rollers having runways on the bottom side of a frame carrying the castors.
Claim 2
Dependent Claim
250 words
In a locking mechanism for sets of castors of the kind, in which the castor wheel is journalled in a fork being able to revolve on a tubular wheel carrier, the improvement which consists in each of the tubular wheel carriers enclosing a tubular part of a locking member, slidingly fitting into the tubular wheel carrier, said tubular part of the locking member being able to move up and down, but not to revolve in said tubular part of the wheel carrier, the tubular part of the locking member carrying a brake flange at the underside which can be brought to bear against the wear surface of the castor wheel in one extreme position of the movement of the locking member, and against the wheel fork in the other extreme position to prevent the latter from revolving, the locking members being pairwise served by means of a lever system being designed as a toggle press, wherein the lever system acting on a pair of castors comprises a short, nearly vertical lever at each castor wheel, one end of said lever being pivotable on a pivot horizontally mounted in the tubular part of the locking member, a connecting rod between the other ends of said short vertical levers and pivotably connected to said ends of the short levers being movable in its longitudinal direction, and a roller being mounted adjacent each of the thus established toggle links, said rollers having runways on the bottom side of a frame carrying the castors.
Claim 3
Dependent Claim
25 words
A locking mechanism according to claim 1, in which the connecting rod of the lever system is slightly arcuated and mounted with a resilient prestressing.
Claim 4
Dependent Claim
38 words
A locking mechanism according to claim 1, in which the lever system is self-locking in the locking position by the short levers being able to swing shortly beyond the vertical position to come to rest against a stop.
Claim 5
Dependent Claim
32 words
A locking mechanism according to claim 1, in which a spring-loaded lock cooperates with notches or similar recesses in the connecting rod to retain the latter in a desired, not locking position.
Claim 6
Dependent Claim
34 words
A locking mechanism according to claim 1, in which a brake lever or foot pedal shaped as a bell crank lever pivotally engaging the connecting rod is arranged to longitudinally move the connecting rod.
Claim 7
Dependent Claim
32 words
A locking mechanism according to claim 1, in which the brake levers or foot pedals of the connecting rods are mutually connected for simultaneous operation of the locking members of all wheels.