Baker Botts L.L.P.
Wood planing machine with an automatic chain tensioner device
 A wood planing machine includes a machine base having left and right mounting short sides, and feed-in and take-out long sides. Left and right pairs of posts are fixed on a top surface of the machine base at the left and right mounting short sides, respectively. A cutter carriage is disposed above the machine base, and has opposite end portions mounted respectively, vertically and movably on the posts. Left and right threaded rods are mounted respectively and rotatably on the mounting short sides of the machine base such that the threaded rods are disposed respectively between the left and right pairs of posts, and extend threadedly through opposite end portions of the cutter carriage for moving the cutter carriage along the posts. Two sprockets are sleeved respectively and fixedly on the left and right threaded rods. A chain has a front chain section and a rear chain section, and engages the sprockets so as to rotate the left and right threaded rods synchronously with each other. A chain tensioner device includes a pushing piece disposed movably inside the chain, and a biasing unit for biasing the pushing piece to contact and move the front chain section away from the rear chain section. 
P & F Brother Industrial Corporation
B F B F
B27C F16H B27C F16H
inventional inventional inventional additional
Chiu-Tsun
Chang