Constant tension clamp

摘要

A hose clamp is provided for compressing a hose radially to hold the hose on a pipe. The clamp has a band for wrapping about the hose over the pipe and includes a first end and a free end. Angled slots extend in parallel adjacent the free end and a housing is attached to the first end and includes first and second end walls. An adjustment screw passes through the first end wall and extends generally in parallel with respect to the bands, the screw being contained within the housing at all times but for a head and a part of a shank adjacent the head. The head is operable to rotate the screw which has a thread in engagement with the angled slots so that rotation of the screw will adjust the band about a hose. The screw also includes a thrust surface adjacent the thread and remote from the head and a helical coil spring is contained in the housing in alignment with the screw and in compressive engagement between the thrust surface and the second end wall. An end piece on the screw engages into the spring sufficient to locate the spring and the screw about a common axis. As a result, after the screw has been rotated to tighten the band, the screw can subsequently be further rotated to compress the helical coil spring and thereby store energy in the spring for use in automatically tightening the clamp should the hose creep to a smaller diameter.