Portable Belt Drive Niggers (Patent No: 473534)

Inventor: Letourneau, Emile M.

Location: Winfield

Comments: N/A

Description:
The embodiment of the invention in which an exclusive property or provelage is claimed are defined as follows:

1. A machine for turning and holding logs on their carriage during sawmill operations comprising a suitable framework operatively positioned below the sawmill floor; three lateral parallel shafts rotatably journalled in pillow blocks affixed to the said framework; a main drive pulley fixed outside the said framework to the centre shaft of the three lateral parallel shafts, said main drive pulley coupled to a suitable power source; secondary drive pulleys fixed, inside the said framework, to the said centre shaft; a driven pulley fixed, inside the said framework and in longitudinal alignment with one of the said secondary drive pulleys, to the second of the said three parallel shafts, such secondary drive pulley and driven pulley loosely coupled by a belt; a nigger bar having interspaced log-engaging teeth, vertically operable through the sawmill floor and adapted at its lower end to slidably fit laterally over the said second shaft and longitudinally over a hoisting pulley affixed to the said second shaft; shook absorbing means mounted on the said nigger bar between the said nigger bar and the said second shaft; a chain fixed by one of its ends to a point on the periphery of the said hoisting pulley and by the other of its ends to the lower end of the said nigger bar; a second chain fixed by one of its ends to a point on the periphery of the said hoisting pulley and by the other of its ends through a tension spring to a lug extruding from the said nigger bar; a driven pulley, fixed inside the said framework and in longitudinal alignment with the other of the said secondary drive pulleys to the third of the three parallel shafts, such pulleys loosely coupled by a belt; a friction pulley fixed, inside the said framework and in longitudinal alignment with the said nigger bar, to the said third shaft; a friction cable wound on the said friction pulley, such cable coupled by one of its ends through a chain to the said nigger bar and by the other of its ends through a tension spring to the said framework; a belt tightening pulley rotatably journalled between parallel supporting beams, at one end thereof, the opposite ends of said supporting beams pivotally connected to the said second lateral shaft at each side of the said driven pulley thereon; means for raising said belt tightening pulley consisting of a U-shaped member pivotally connected by its ends to the said parallel beams and pivotally connected at its mid-point to one end of a lever, which is fixedly connected by the other of its ends to a lateral shaft; a second lever fixedly connected by one of its ends to the said lateral shaft and pivotally connected at the other of its ends to one end of a connecting rod which is pivotally connected by its other end to the lower end of an operating lever, the said operating lever extending vertically through the sawmill floor and pivotally supported at its mid-point in a suitable lever mount positioned to the sawmill floor; a second belt tightening pulley rotatably journalled between parallel supporting beams and at one end thereof, the opposite end of said beams being pivotally connected to the said third lateral shaft at each side of the said driven pulley thereon; means for lowering the said belt tightening pulley consisting of a U-shaped member pivotally connected by its ends to the said parallel beams and at its mid-point to one end of a lever which is fixedly connected by the other of its ends to a lateral shaft; a second lever fixedly connected by one of its ends to the said lateral shaft and pivotally connected by the other of its ends to one end of a connecting rod, the other end of the said connecting rod being pivotally connected to one arm of a bell crank the other arm of which is pivotally connected to a vertically operable shaft, said shaft extending vertically through the sawmill floor; means for maintaining said second belt tightening pulley in a raised inoperative position consisting of a cable attached by one of its ends to the parallel supporting beams and at the other of its ends to a tension spring affixed to the said supporting framework; vertical guide members affixed to the sawmill floor, longitudinally parallel on each side of the said nigger bar; shock absorbing means mounted on the said parallel members.

2. A machine for turning and holding logs on their carriage during sawmill operations comprising a suitable framework; lateral parallel shafts rotatably affixed to the said framework; a main drive pulley and secondary drive pulleys affixed to one of the said shafts; a driven pulley .fixed in longitudinal alignment with one of the said secondary drive pulleys to another of the said shafts and loosely coupled to the said secondary drive pulley by a belt; a vertically operable nigger bar adapted to slidably fit laterally over the last mentioned shaft and longitudinally over the hoisting pulley affixed to the said shaft; shook absorbing means mounted on the said nigger bar between the said nigger bar and the said shaft; a chain fixedby one of its ends to a point on the periphery of the said hoisting pulley and by the other of its ends to the lower end of the said nigger bar; means for limiting the rotation of the said hoisting pulley during the downward travel of the said nigger bar; a second driven pulley fixed, in longitudinal alignment with another of the said secondary drive pulleys, to another of the said lateral parallel shafts and loosely coupled to the said secondary drive pulley by a belt; a friction pulley fixed to the last mentioned shaft in longitudinal alignment with the said nigger bar; means associated with the said friction pulley connected to the said nigger bar and adapted to maintain pressure of the said nigger bar against a log positioned on the sawmill carriage; means for tightening the said loosely coupled belts singly or in unison, to engage said secondary drive pulleys and said driven pulleys, said belt tightening means operated and controlled from a preferred location on the sawmill floor; means for restricting lateral movement of the said nigger bar and guiding the said nigger bar during longitudinal oscillation; shock absorbing means mounted on the last mentioned means;

3. A machine for turning and holding logs on their carriage during sawmill operations comprising a suitable framework; lateral parallel shafts rotatably affixed to the said framework; a main drive pulley and secondary drive pulleys affixed to one of the said shafts; a driven pulley fixed, in longitudinal alignment with one of the said secondary drive pulleys, to another of the said shafts and loosely coupled to the said secondary drive pulley by a belt; a vertically operable nigger bar adapted to slidably fit laterally over the last mentioned shaft and longitudinally over a hoisting pulley affixed to the said shaft; shook absorbing means mounted on the said nigger bar, between the said nigger bar and the said shaft; means connected to the said hoisting pulley and the said nigger bar and adapted to raise the said nigger bar vertically coincidentally with the rotation of the said hoisting pulley; a second driven pulley fixed, in longitudinal alignment with another of the said secondary drive
pulleys, to another of the said lateral parallel shafts and loosely coupled to the said secondary drive pulley by a belt; a friction pulley fixed to the last mentioned shaft in longitudinal alignment with the said nigger bar; a friction cable wound on the said friction pulley, such cable attached by one of its ends through a chain to the said nigger bar and by the other of its ends through a tension spring to the said framework; means for tightening said loosely coupled belts singly or in unison, to engage said secondary drive pulleys and driven pulleys, said belt tightening means operated and controlled from a preferred location
on the sawmill floor; means for restricting lateral movement of the said nigger bar and guiding the said nigger bar during longitudinal oscillation; shock absorbing means mounted on the last mentioned means.

4. Means of applying power to a vertically operable nigger bar comprising a main drive pulley and secondary drive pulleys fixed to one of a plurality of parallel shafts such main drive pulley being coupled to a suitable power source; a driven pulley fixed to another of the said parallel shafts and loosely coupled by a belt to one of the said secondary drive pulleys; a hoisting pulley fixed to the last mentioned shaft, the said nigger bar being adapted to slidably fit over the said hoisting pulley and the last mentioned shaft; means associated with the said hoisting pulley and adapted to raise the said nigger bar vertically on rotation of the said hoisting pulley; means for limiting the rotation of the said hoisting pulley during the downward travel of the said nigger bar; another driven pulley affixed to another of the parallel shafts and loosely coupled by a belt to another of the said secondary drive pulleys; a friction pulley fixed to the last mentioned shaft; means associated with the said friction pulley and connected to the said nigger bar adapted to maintain pressure of the said nigger bar against a log positioned on the sawmill carriage; means for tightening the said loosely coupled belts singly, or in unison to engage their respective secondary drive pulleys and driven pulleys such means controlled from a point remote from the said nigger bar; means for restricting lateral movement of the said nigger bar and guiding the said nigger bar during longitudinal oscillation.