Self-orienting revolving fixture

Claim 2

In a self-orienting revolving fixture of the type which has substantially flat, parallel plates including a lower plate for attachment to the top of a relatively fixed furniture base and an upper plate for attachment to the bottom of a furniture member, antifriction means between the plates spacing them apart and providing for free relative rotation about a central axis, coil spring means which has a plurality of spring coils substantially concentrically surrounding the central axis and spaced radially therefrom, said coils having opposite ends, a pair of circumferentially spaced upstanding lugs on the lower plate engaging both of the opposite spring ends when the plates are in said oriented position, a depending pulling lug on the upper plate which is radially adjacent one of the upstanding lugs in the oriented position and which engages one of said spring ends to stress the spring means as the plates are relatively rotated in one direction from said position, and stop means on said plates for limiting their relative rotation from said position, the improvement comprising: guide finger means on one of the plates in a position which is between the upstanding lugs and on the same side of the pivot axis when the plates are oriented and radially inwardly of the spring, said guide finger means having a very small area of contact with the radially inward side of the spring coils in a location behind the pulling lug when the coils are stressed during relative rotation of the plates so as to restrict bodily shifting movement of the coils with respect to the pivot axis and prevent differential stressing of the spring.

Claim 3

The revolving fixture of claim 1 in which there is a single guide finger.

Claim 4

The revolving fixture of claim 1 in which the guide finger means and the stop means are both on the upper plate.

Claim 5

In a self-orienting revolving fixture of the type which has substantially flat, parallel plates including a lower plate for attachment to the top of a relatively fixed furniture base and an upper plate for attachment to the bottom of a furniture member, antifriction means between the plates spacing them apart and providing for free relative rotation about a central axis, coil spring means which has a plurality of spring coils substantially concentrically surrounding the central axis and spaced radially therefrom, said coils having opposite ends, a pair of circumferentially spaced upstanding lugs on the lower plate engaging both of the opposite spring ends when the plates are in said oriented position, a pair of depending pulling lugs on the upper plate each of which is radially adjacent one of the upstanding lugs in the oriented position so that each engages one of said opposite spring ends to stress the spring means as the plates are relatively rotated one way or the other from said position, and stop means on said plates for limiting their relative rotation from sAid position, the improvement comprising: guide finger means on one of the plates in a position which is between the upstanding lugs and on the same side of the pivot axis when the plates are oriented and radially inwardly of the spring, said guide finger means having a very small area of contact with the radially inward side of the spring coils in a location behind the pulling lug when the coils are stressed during relative rotation of the plates so as to restrict bodily shifting movement of the coils with respect to the pivot axis and prevent differential stressing of the spring.

Claim 6

In a self-orienting revolving fixture of the type which has substantially flat, parallel plates including a lower plate for attachment to the top of a relatively fixed furniture base and an upper plate for attachment to the bottom of a furniture member, antifriction means between the plates spacing them apart and providing for free relative rotation about a central axis, coil spring means which has a plurality of spring coils substantially concentrically surrounding the central axis and spaced radially therefrom, said coils having opposite ends, a pair of circumferentially spaced upstanding lugs on the lower plate engaging both of the opposite spring ends when the plates are in said oriented position, a pair of depending pulling lugs on the upper plate each of which is radially adjacent one of the upstanding lugs in the oriented position so that each engages one of said opposite spring ends to stress the spring means as the plates are relatively rotated one way or the other from said position, and stop means on said plates for limiting their relative rotation from sAid position, the improvement comprising: guide finger means on one of the plates in a position which is between the upstanding lugs and on the same side of the pivot axis when the plates are oriented and radially inwardly of the spring, said guide finger means having a very small area of contact with the radially inward side of the spring coils in a location behind the pulling lug when the coils are stressed during relative rotation of the plates so as to restrict bodily shifting movement of the coils with respect to the pivot axis and prevent differential stressing of the spring.

Claim 7

The revolving fixture of claim 4 in which the lugs of a pair are spaced circumferentially around the plate spaced from each other at an angle substantially less than 180*, there is a single guide finger positioned radially inwardly from the spring means on a radius of the plate which bisects said angle, and the stop means comprises a boss on one of the plates which is spaced 180* from the guide finger in a position to contact one of the lugs on the other plate to limit relative rotation of the plates.

Claim 8

The revolving fixture of claim 5 in which the guide finger and stop boss are both on the upper plate.

Claim 9

The revolving fixture of claim 4 in which there is a single guide finger and a single stop boss, both on the upper plate on a diameter of said plate which bisects the angle defined by the lugs.

Claim 10

The revolving fixture of claim 4 in which the guide finger means is provided with antifriction means on the side toward the spring.

Claim 11

The revolving fixture of claim 4 in which the spring means comprises a single spring.