Quick release adjustable height stem for bicycle handlebars has quick release lever that controls clamping of two interference blocks against toothed portion on quill inserted into head tube to adjust height of stem longitudinal tube

摘要

The adjustable handlebar stem includes a vertical quill (70) with a toothed portion (701) at its upper tube end, and a lateral longitudinal stem tube (80) having a faceplate (801) at one end for clamping the handlebars and two links (803, 804) at its other end for pivotal connection on the side of the upper end of the quill (70). The stem longitudinal tube includes a space containing two interference blocks (90,91) in engagement with the toothed portion of the quill. A quick release lever (100) controls clamping of the two interference blocks to allow pivotal adjustment of the stem height when open and locking of the toothed parts (903,904) of the interference blocks against the teeth of the quill when the quick release lever is in it locked position.