Portable cervical traction device using constant force springs

Abstract

A compact cervical traction apparatus having a carriage which is slidably disposed over a base, the carriage carrying a head support band. A pair of springs that provide a uniform traction force over the entire range of carriage movement are enclosed within a spring housing at the rear of the base. The springs are constant force springs and an uncoiled portion of the first spring is disposed below an uncoiled portion of the second spring. The uncoiled portion of the first spring is attached to a Z-shaped member having an elongated trailing end that is mounted to the carriage so as to bias the carriage. The uncoiled portion of the second spring is attached to a lip member that is disposed to securely fit within the Z-shaped member and thereby combine the traction force of the second spring to that of the first spring. An L-shaped disengaging plate has a portion which passes between the uncoiled portions of the springs proximate attachment of the lip member to the Z-shaped member. The disengaging plate also has a cam surface portion. Pressure applied to the cam surface portion causes the disengaging portion of the plate to separate the lip member and the Z-shaped member sufficiently to prevent coupling. Such pressure is selectively supplied by a cam pivotably secured to the spring housing. The constant force springs each provide a traction force of four pounds to the carriage.

Dependencies are inferred from the claim text.