USRE8160E - Improvement in direct-acting steam-feed works for circular-saw mills - Google Patents

Description

I DeW. 0. PRESCOTT. Direct Acting Steam Peed Works for Circular Saw Mills.

No. 8,160. Reissued April 9,1878.

m W r.w m 1m Q DH u Q J Lg N PATENT OFFICE- i51 "w'I'jrcLIN'roiI PnEsoo'r'T, or MARINETTE, wrsoolvsirt V I MPROVEMENTflN' DIRECT-ACTING STEAM-FEED WORKS FOR CIRCULAR-SAW MILLS.

Specification forming part of Letters Patent No. 174,004, dated February 22, 1876,; Reissue No. 5,160, dated Y April 9, 1878; application filcdMarch QS, 1878.

To all whom it"may concern: 7

Be it known that I, DE Wrrr CLINTON PRESCOTT, of Marinette, county of Oconto, and State of Wisconsin, have invented certain new and usefutImproi ements in Direct-Acting Steam-Feed Works for CirculanSaw Mills, which are fully set forth in the followipg specification, reference bein g had to the accompanying drawings. v

My invention relates to that particular part of circular on rotary saw mills xter-med the feedworks, by, means of which the log (being supported upon its carriage) is propelled or fed against the saw, and also is returned or gigged back to, its original position after a portion has been-sawed from it, thus accomplishing, in conjunction with other mechanisms, the manufacture of lumber; and my object is to dispense with the combination of belts, pulleys, shafts, frictions, and gearing which is now in general use for that purpose, and also to obtain a more prompt and efficient action of the log-carriage when in operation.

The principle of my invention consists in applyin g the power of steam directly to the logcarriage, and by this power, which I cause to.

nates asteam-cylinder, of the same length as the greatest run or travel 0f the log-carriage, proper allowance also being made for clearance at each end, to prevent the piston from striking the cylinder-heads B and G, -which are fitted to it.

D is a piston-head, constructed ina manner steam-tight, and of suitable form. To this is attached one end of piston-rod E, which passes out of cylinder A through the stufifingbox in cylinder-head 0,,the other end thereof being attached securely to the log-carriage means of the bracket F, which is bolted tovit ata suitable point to obtain a proper travel of the carriage, and at the same time to secure a corresponding regular travel of thepiston-head D in cylinder A. The said piston-rod E is composed of iron pipe, though steel pipe orsolid rods may. be used. l v

Fig. 2 shows a sectional view of the steamchest G, containing the slide-valve H, which operates-upon,alvalveseat in lower part of steam-chest Gr, in which are steam-portsl and J and exhaust-port V 'The slide-valve H is so constructed that, when placed upon the center of its stroke, it will present exhaust-openings to both of ports I and J. L and M aresteam-pipes leading from the openings of steam-ports I and J to each corresponding end of cylinder A. N is a pipe connected at opening of exhaust-port K to convey away exhausted steam. O is a valve stem or rod attached to slide-valve H, and also to lever P, with its fulcrum R, which, with connecting-rod S and hand-lever T, enables the sawyer to operate with the slide-"alve H. (See plan of steam-chest, Fig.3.) U is a steam-pipe leading from steam-chest G to a boiler from which power is supplied,.which it has not been deemed necessary to show. Portions of steamcylinder A, piston-rod E, and steam-pipes L and M are removed; but they are supposed to be of proper length.

The operation of the machine is as follows:

The cylinder A being securely fastened to the mill-floor or overlay-timbers, and the pistonrod E attached to the log-carriage, the valve levers and rod P, T, and S are placed in position, as shown, and steam admitted through steam-pipe U into steam-chest. G. A log is placed upon the carriage when in position in front of the saw and somewhat to the left of the position shown in Fig. 4. Then, by means of the hand-lever T, the slide-valve H is moved in the right direction to admit suflicient steam through steam-pipe L into the cylinder .A to impart motion to the log-carriage by means of the piston-head D, piston-rod E, and bracket F. In this manner the log. (being upon the carriage in proper position) is propelled or fed against the saw, which cuts 011' a slab, board, or plank, as the case may be, as the log passes.

. best mode of applying the principle of my in-v This being accomplished, the position of the hand-lever T is reversed, and with it the'slidevalve H, which exhausts the steam just employed, and admits live steam into the cylinder A through steanrpipe M, by which the log carriage is forced or giggcd back to its original position before the saw, ready for the next cut, the sawyer maintaining complete control oft-the carriage at all times by means of the hand-lever T, as before stated.

In the construction of my apparatus I have adopted and shown'wliat I have deemed the vention; but it can he successfully applied in other ways-- for instance, the steam-cylinder can be attached to and travel with the-log. carriage.. Again, t'wo cylinders can be employed, with one of which-to operate the log carriage in feeding-the other to run or gig it back to its original position.

Having thus described the principle and construction, as well as the operation, of my invention, I will'state what I claim and desire to secure by Letters Patent:

'l. Themethod of applying steam-power in a direct manner to operate log-carriages of circular 0r rotary saw mills in the process of sawin g or manufacturing lumber, as specified.

2. In a circular-saw mill, the log-carriage, in COIll'billtlfiOll with a steanncylindcr of about the same length as the grez'itestrun or travel of the carriage, and provided with a piston, either the cylinder or piston being connected directly to the carriage, substantially as and for the purpose set forth.

3. The log-carrier, in combination with a steam-cylinder of aboutthe same length as the greatest run of the carriage, a piston fitted within the cylinder and connected directly to the carriage, and mechanism whereby the travel of the carriage and operation of the steam-feeding device may be regulated, substantially as described.

4. The steam-cylinderA in combination with the piston-head D, pistonrod E, bracket F, attached to the log-carriage, and steam-chest G, provided with valve Hand supply and exhaust ports, lever P, connected to the valvestem, and hand-lever '1, connected to the lever P, substantially as and for the purpose set forth.

DE m CLINTON rnnseorr.

- Witnesses:

G130. H. CANNON, NV. J. TAYLOR.

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