Log rest with rack and pinion system
A new log support and clamp system (log rest) for a portable sawmill, having a log rest and a log dog. The log rest features a rack and pinion for adjusting a vertical position of the log rest using an actuation mechanism located on the operator's side of the portable sawmill, which improves the ability of the user to affix the log in place for sawing. Also, a portable sawmill having such a log rest.
1. A log rest assembly comprising:
a vertically extending log rest post;
a post housing assembled with the post, said post being vertically displaceable therewith; and
a rack secured to the post and a pinion secured to the post housing, the rack and pinion being operable to raise and lower the post by vertically sliding the post in relation to the post housing;
wherein the rack and pinion comprises a tensioned chain attached to the log rest assembly; and a ratcheted wheel attached to the post housing for engaging teeth on the tensioned chain.
2. The log rest assembly of claim 1 further comprising an actuation mechanism comprising:
a second ratcheted wheel;
a rotatable shaft extending from the ratcheted wheel to the second ratcheted wheel; and
a handle attached to the second ratcheted wheel for actuating the ratcheted wheel,
wherein rotation of the handle causes the ratcheted wheel to traverse the chain, thereby raising or lowering the vertical position of the post.
3. The log rest assembly of claim 2 further comprising a pawl having a tooth for engagement with a notch of the second ratcheted wheel, wherein the pawl locks the vertical position of the post.
4. A log rest assembly comprising:
a vertically extending log rest post;
a post housing assembled with the post, said post being vertically displaceable therewith; and
a rack secured to the post and a pinion secured to the post housing, the rack and pinion being operable to raise and lower the post by vertically sliding the post in relation to the post housing;
wherein the post has a wheel at a top end.
5. The log rest assembly of claim 3 wherein in an unlocked position, the post is vertically displaceable, and in a locked position, the post is vertically non-displaceable.
6. The log rest assembly of claim 3 wherein the pawl and the notch are configured to allow free movement of the rack and pinion when the pawl is unlocked.
7. The log rest assembly of claim 1 , wherein the rack and pinion are manually operable to raise and lower the post.
8. The log rest assembly of claim 1 affixed to a bed of a portable sawmill.
9. The log rest assembly of claim 1 , further comprising a handle for manually operating the rack and pinion.
10. A log rest assembly comprising:
a post;
a post housing, said post being vertically displaceable therein; and
a rack and pinion for raising and lowering the post, wherein the rack and pinion comprises:
a tensioned chain attached to the log rest assembly; and
a first ratcheted wheel attached to the post housing for engaging teeth on the tensioned chain; and
an actuation mechanism comprising:
a second ratcheted wheel;
a rotatable shaft extending from the first ratcheted wheel to the second ratcheted wheel; and
a handle attached to the second ratcheted wheel for actuating the first ratcheted wheel,
wherein rotation of the handle causes the first ratcheted wheel to traverse the chain, thereby raising or lowering the vertical position of the post.
11. The log rest assembly of claim 10 further comprising a pawl having a tooth for engagement with a notch of the second ratcheted wheel, wherein the pawl locks the vertical position of the post.
12. The log rest assembly of claim 11 , wherein in an unlocked position, the post is vertically displaceable, and in a locked position, the post is vertically non-displaceable.