Tiltable x-ray examination table

Claim 2

In an x-ray examination apparatus including a base, a tiltable patient-table carried by the base, a carriage displaceable on said table, and drive means for displacing the carriage, the improvement in combination therewith of a safety device for quickly stopping the drive means from further displacing said carriage when said carriage collides with an object, comprising first means for sensing the amount of tilt of the table and for providing a corresponding signal, second means for sensing the impact and deceleration of the carriage at the time of said collision and providing a corresponding signal, actuator means responding to signals from said first and second means for directing said drive means to cease displacing said carriage, when either of said first and second means produces a signal that departs from a predetermined value relative to the other signal.

Claim 3

Apparatus according to claim 1 operable with a source of electrical current, wherein said drive means includes an electric motor and circuit means for conducting current from said source to said motor, said first means comprising a first potentiometer and cursor, and tilting of said table causes movement of said first cursor, said second means comprises a second potentiometer and cursor, and helical spring means having its ends secured to said carriage and an intermediate part between said ends secured to said drive means and to said second cursor, whereby a collision and deceleration of said carriage produces corresponding movement of said second cursor, said apparatus further comprising circuit means which includes said first and second potentiometers and their cursors, and third means for analyzing said signals from said first and second means and providing a resultant signal, said actuator means being responsive to said resultant signal for controlling said drive means.

Claim 4

Apparatus according to claim 1 wherein said first means comprises a force-measuring potentiometer for measuring force resulting from said collision, said second means comprises a position-measuring potentiometer for measuring the amount of tilt of said table.

Claim 5

Apparatus according to claim 3 wherein said actuator means comprises a wheatstone bridge circuit which includes as branches thereof, said potentiometers of said first and second means.

Claim 6

Apparatus according to claim 2 further comprising a compressible grip operable with said drive means, wherein speed of displacement of the carriage corresponds to compressive force applied to said grip.

Claim 7

Apparatus according to claim 5 further comprising at least one adjustable compensating potentiometer which is varied by the force applied to said grip, and is in circuit with said force-measuring potentiometer.