US117828A

US117828A - Improvement in machfnes for turning logs

Info

Publication number: US117828A
Authority: US
Publication date: 1871-08-08
Anticipated expiration: 1888-08-08

Description

swan .I

EDWARDHSTEARNS.

Improved Log-Turning Machine.

Patented Augu t 8, 1871.

INVENTGR WITNESSES EDWARD H. STEABNS. Improved Log-Turning Machine.

Patented August 8, 1871.

a ll EDWARD H. STEARNS. Improved Log-Turning Machine. "7,828. I Patented August 8, 1871 INVFQ 1 EDWARD H. STEARNS, OF ERIE, PENNSYLVANIA.

PATENT OFFICE.

IMPROVEMENT lN MACHINES FOR TURNING LQGS.

Specification forming part of Letters Patent No. 117,828, dated August 8, 1871.

To all whom it may concern.-

Be it known that I, EDWARD H. STEARNS, of Erie, in the county of Erie and State of Pennsylvania, have invented certain Improvements in Machines for Turning Logs in Saw-Mills, of which the following is a specification:

The first part of my invention relates to the construction and operation, in combination with the gearing e and G, hereinafter more fully de' scribed, ofa toothed are or bar, which moves nearly vertically, aud varies according to the size and position of the log to be moved, and is provided with a series of teeth upon its upper portion, while its lower portion is provided with cogs, by means of which a pinion fixed upon a shaft is caused to run the bar upward when the shaft is revolved. The teeth upon the upper end of the bar engage with the log on the carriage, and turn it as may be required. The bar and the pinion cooperate to produce that result. The second part of my invention relates to the construction and operation of a rockingguide, which turns or rocks on the same shaft with the pinion above mentioned. The said toothed bar is made to pass through this rocking-guide, which rocks or turns in such a manner upon the shaft that the cogs of the bar shall remain properly in gear with the pinion, whether the upper end of the bar be moved backward orforward as far as required. The third part of my invention relates to the construction of a stirrup in combination with a slot in the said toothed bar, or any equivalent formation in its place, in such a manner that the stirrup will limit the downward movement of the bar. The fourth part of my invention relates to the use of an elastic buffer in combination with the longitudinal slot in said bar, or with any equivalent formation of such bar, to receive the concussion of the metal at the upper end of the slot upon the bottom of the stirrup, and, by reason of its elasticity, prevent any hurtful jar in the machine. Such concussion will take place when the bar is allowed to run down by its own weight. The fifth part of my invention relates to the construction and arrangement of a spring-cog, which is the uppermost one of the series on said bar, a-nd in combination with said bar and pinion, in such a manner that when said bar is allowed to run down as far as the stirrup will allow, and the shaft is still revolved by the momentum of the frictionwheel, this spring will readily yield to each cog of the pinion and thus prevent breakage. The sixth part of my invention relates to the construction and operation, in combination, of the brake, which, by its peculiar form and weight, presses the toothed side of the said bar against the log so that the teeth may engage with the same, a shoulder on the brake and a spring-tooth on said bar which engages with that shoulder, so that the brake may operate upon the bar up to a higher point than it would otherwise do, after doing which the tooth will allow it to pass. In case the bar engages with a log that will not yield laterally the tooth will yield and allow the bar to swing back as it rises, and prevent accident to the machinery; and further, of another brake on the opposite side of the bar, which will be more fully hereinafter described. The function of that brake is simply to press the bar from the log so that it may pass down by its own weight more readily and without friction against the log. The seventh part of my invention relates to the combination of the rocking-frame for carrying the shaft H of the friction-wheel l and band-wheel M with the said toothed bar E in such a manner that said shaft H shall always in operation preserve its parallel position to the shaft Z.

' Figure 1 is a side elevation of a machine embracing my improvement. Fig. 2 is a front elevation of the same. Fig. 3 is a vertical sectional view, on an enlarged scale, of the toothed are or bar E, the rocking-guide, the spring-cog, pinion G, and friction-pulleys g g. Fig. lisa detached and enlarged view of t11e frict1on-pulleys g g, which are located in the rocking-guide g. Fig. 5 shows an arc of a smaller circle, for use where there is little room below the floor. Fig. 6 shows a cross-section of the same bar constructed in a different form, the back side of it being in a T- form, which is used instead of the slot a, shown in several of the figures, and embraced by a box through which the stirrup opasses.

In Fig. 1 is shown a side view of the toothed bar E, and in Fig. 2 a front view. The front plate of it is made wide enough to afford sufficient space for cogs of the required length, to make them strong, extending up and down the center, and for bearing-surface on each side of the cogs for the rims G G of the pinion G, which partly sustain its weight, and upon which it turns when the upper end is moved forward or backward. The back part of the bar has the form of a flange, extending back from the front plate, and it is made so narrow that on each side of it, on the back of the front plate, there will be space enough for bearing-surfaces for the anti-friction wheels g g g 9, while the flange divides each pair of them. These wheels hold the bar against the rims G G of the pinion G, and guide the bar in its upward and downward movements. These rims G G serve also to prevent the cogs of the bar from meshing too deeply with those of the pinion G. In the upper end of the slot at is fastened a buffer of soft India rubber or other suitable elastic substance, by means of which, when the bar E is run down by its own weight and caught by the stirrup o, the shock will be broken, as before stated. Upon the lower end of the bar E is the blank 0, without cogs. This is provided in order that the bar may stop in its upward movement when its lower end reaches the pinion G, thus limiting its upward movement as the stirrup 0 does its downward movement. This toothed bar may be modified in form, as shown in Figs. 5 and 6. I prefer the form and gearing shown in Figs. 1 and 2. The rocking-guide g, turning freely on the shaft Z, inclosing and holding the anti-friction pulleys g g g y and the pulley G, and inclosing and guiding the toothed bar and keeping it always in gear with the pulley G, completes the construction for the upward movement of the bar, to the end that the teeth may engage and turn the log on the carriage as may be desired. The power to set it in motion is applied by means of the friction-pulley K, which turns the shaft Z. Its upward and downward movementis limited, as before shown, by the blank 0 and the stirrup o, and the shock caused by its falling upon the bottom of stirrup o is broken and rendered harmless by the buiier WV, before described, which, in combination with the spring-cog, aids the latter in preventing injury from the momentum of the friction-wheel and in starting the bar upward on its return movement into gear with the rigid cogs. In Fig. 3 is shown an enlarged view of the spring cog 0, showing plainly its construction. It is equally efficient with the others in the upward movement of the bar, but in the downward movement it yields to the cogs of the pinion until the momentum of the irictiolrwheel is exhausted. A hinged cog, 0 as shown in Fig. 3 on the right, is regarded as a mechanical equivalent and will answer the same purpose. The brake N, shown in Fig. 1, by its peculiar form and weight, by the weight n, and its suspension upon the same shaft X with the stirrup 0, exerts a constant pressure against the back of the toothed bar as it commences to rise and throws it forward and moves it with its teeth against the log; and, in order that it may continue to exert such pressure up to a higher point than it would otherwise do, itis provided with the shoulder Z, which engages with the spring-tooth Z in the bar, and thus the bar and brake are held fast together until the spring-tooth is raised so high that the relative position of the tooth and shoulder become so changed that the teeth pass easily over the shoulder during the operation of the brake. The location of its pivot with respect to the are or bar, and to the form of the brake itself, is such that leverage and friction co-act to produce the desired action, which is greatly increased by a small force applied by the operator to the weight a, as is more clearly shown in Fig. 1 of the accompanying drawing. In front of the toothed bar is another brake, P having thegeneral form of a bell-crank lever, bearing and turning upon the shaft X It may be operated by the rod .9 and lever S. The upper part of the brake P is double, each twin-bar being provided with anti-friction pulley K, and they are placed just far enough apart to allow the teeth 1' to pass between them or one bar only, with a single pulley, may be used. Precisely the same principle which governs the action of the brake N governs the action of this brake also, except that after the bar has been thrown back some distance the rollers. will come in contact with the face of the bar and lessen the friction of the downward movement of the same. To return to the subject of the rocking-guide g, such is its structure and operation in connection with the pinion G that the bar is made to press its teeth against the log with equal force all the way from the lowest to the highest tooth. WVith its fixed pivot on the shaft which does not rise and fall with the bar, it performs its work more perfectly than any heretofore in use. All logturners employing toothed bars similar to mine, hcreinbefore described, have been amenable to at least one sorious objection, namely, that the pressure of the bar toward the log has not been the same at different heights. It is not sufficient at the beginnin g of the upward movement, is about so midway of it, and at the end of it is so great as rather to lift the log than turn it. A happy result of the form and the mode of hinging and gearing my bar is, that when its teeth strike the edge of the log in the upward movement they do so with a force that is equal and uniform from the first to the last. This result is due to the fact that the pivot of the bar is stationary. It is obvious that if the pivot were to be raised the direction of the bar in respect to the log would be changed, and, upon being raised to a level therewith, the bar would (h'ive the log squarely against the knee. The arc-form of the bar is superior in its mode of action to any other. Its action is similar to that of a wheel with its teeth up 011 its periphery which lifts a part of the weight of the log, and the teeth as they rise incline away from the knees, the friction against them is lessened, and the log is therefore more easily turned. The spur-gearing which I employ is considered much superior to the chain and sheave arrangement, because it is less expensive to construct, to set up in the mill, and less cumbersome and complicated, and more durable. The chain, when drawn tightly around the spool under a heavy pressure, soon chaws itself out. When a chain is merely stretched the planes of its alternate links out each other at right angles, but when the chain is wound with great force around a spool the tendency of all is to fall flat upon it, the result of which is that they twist and grind each other in their gearing, and power as well as metal is wasted, and the chain soon destroys itself.

In the drawing of detached parts in Fig. 1, H H are the fixed bearin gs for the rocking-sh aft H H H are the rigid arms, and in these arms the shaft 5 has its bearing, and upon this shaft revolve the friction-wheel l and the band-wheel M. N ow, by means of the lever B, which is bolted to an arm of the rocking-shaft, the friction-pulley l is thrown into or out of contact with the friction-wheel 7:, just as the operator may desire; and it is obvious, upon observing the operation of this frame, that the shaft 1, whether raised or depressed, will preserve its parallelsm with the shaft or pulley K, so that the faces of the friction-wheels will come squarely together and the band-wheel M will not be thrown out of its proper vertical plane.

I claim 1. The toothed bar or are E operated by rack or spur-gearin g e and G, substantially as and for the purpose described.

2. The rocking-guide g, either with or without the anti-friction rollers g, in combination with the toothed are or bar E, constructed and arranged substantially in the manner and for the purpose described.

3. The stirrup o, in combination with the bar E, provided with slot a, constructed substantially as and for the purpose described.

4. The elastic buffer WV, in combination with the are or bar E, constructed substantially as and for the purpose described.

5. The sprii'ig-cog e, in combination with the are or bar E and pinion G, constructed substantially as and for the purpose described.

6. The combination of the brake N having the shoulder Z, the spring-tooth Z, and the brake P constructed and arranged substantially as and for the purpose described.

7. The rocking-frame H having the arms H H, the friction-wheel l with its shaft 1, frictionwheel K, with its shaft Z, the pinion G, and the toothed bar E, in combination, each constructed and all operated substantially as set forth.

E. H. STEARNS.

YVitnesses:

EDM. -F. BROWN, ALEX. M. STOUT, Jr.