US436203A - Saw-mill dog - Google Patents

Description

2 SheetsShet 1.

(No Model.)

' M. E. BENSON.

SAW MILL DOG.

0 H [l I IN VENTOI? WITNESSES.

A from/5Y8 2 Sheets-Sheet 2.

(No Model.)

M. E. BENSON.

SAW MILL DOG.

No. 436,203. Patented Sept. 9, 1890.

[I li k //v VENTOH mg z A TTORNE Y8 UNITED STATES PATENT OFFICE.

MARCUS E. BENSON, OF WEST PLAINS, MISSOURI.

SAW=M|LL DOG.

SPECIFICATION forming part of Letters Patent No. 436,203, dated September 9, 1890.

Application filed March 24, 1390.

To all whom it may concern..-

Be it known that I, MARCUS E. BENSON, of West Plains, in the county of Howell and State of Missouri, have invented a new and Improved Saw-Mill Dog, of which the following is a full, clear, and exact description.

The object of the invention is to provide a new and improved saw-mill dog which is simple and durable in construction, very effective in operation, and permits of freely moving the log up or down in case of knots or crooks striking the collar of the saw, without, however, releasing the dog.

The invention consists of certain parts and details and combinations of the same, as will be hereinafter more fully described, and then pointed out in the claims.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar letters of reference indicate corresponding parts in all the figures.

' cured a standard B, on which is held an adjustable frame 0, having near its upper and lower ends a slot 0, through which pass bolts D, screwing into the standards B and permitting a horizontal adjustment of the said frame O. Vhen the latter is in its innermost position, as shown in Fig. 3, its inner planed edge 0 fits into a vertical guideway B, formed on the standard B and serving to limit the inward motion of the frame 0. The bolts D are then in the right-hand end of the slots 0, as is plainly shown in Fig. 1.

In order to conveniently move the frame 0 horizontally on the bolts D in order to adjust the dogs farther in or nearer to the side of the.log, levers E and E are provided, pivoted at E or E respectively, to the standard B and preferably made of L shape, one end of each being pivoted to the frame 0, while the other ends of the two levers are pivotally connected with each other by the link E so that when one lever is moved the other moves simultaneously, and the frame C is regularly Serial No. 345,020- (No model.)

Fig. 3, the two guideways O and 0 being engaged by a vertical sliding carriage F, carrying the upper dog G, provided with the usual point- G, adapted to engage the log under treatment.

On the upper part of the carriage F is mounted to turn in suitable bearings the transversely-extending shaft H, on which is secured a gear-wheel I, in mesh with a rack J, fitted to slide vertically on the inner face of the projection 0 The rack J is supported at its lower end on a vertically-extendingcoiled springK, extending through a recess 0, formed in the projection C the upper end of the spring being fastened to the top of the frame 0. (See Fig. 1.) On the lower end of the rack J is secured a slide or carriage L, fitted to slide on the guideways O and O similarly to the carriage F, the said slide L supporting the lower dog N, provided with the usual upwardly-extending point N, adapted to engage the log from the under side, as is plainly shown in Fig. 1. v The gear-wheel I, previously mentioned, is adapted to be engaged by a pawl 0 held on two bolts P, extending transversely through slots Q in the lever Q, f ulcrumedjloosely on the shaft H. The bolts P also support on the'opposite face of the lever Q an arm R, having a segmental edge R, adapted to be pressed in contact by a spring R with the segmental edge F, formed on the carriage F, concentric with the shaft II on which the lever Q'is fulcrumed. The said arm R is also adapted to be engaged by the beveled end of a plate F secured to the top of the carriage F and having its point passing onto the segmental edge F of the carriage F, as is plainly shown in Fig. 2.

When the lever Q is thrown into a vertical position, the arm B travels up. the beveled end of the plate F so that the said arm slides outward and carries along the pawl O, which latter is thus disengaged from the gearwheel I.

When the lever Q is moved downward, so that the arm R passes off the beveled end of the plate F then the spring R pressing on the said arm R, causes the latter to slide inward, thereby moving the pawl O in the same direction-that is, in engagement with two teeth of the gear-wheel I.

On the shaft H and at its front end is fulcrumed loosely a cam S,supported on an arm S, fastened to the lever Q, so that the said cam S turns with the swinging of the lever Q, as hereinafter more fully described.

The cam S is adapted to engage with its cam-edge the releasing-arm T, pivoted at T to the dog G, and adapted to engage with its outer end T the log under treatment next to the point G, so as to withdraw the latter whenever desired, and as hereinafter more fully described.

The operation is as follows: The operator first moves the lever Q into a vertical position, so as to disengage the pawl 0 from the gear-wheel I, as previously described, to enable the operator to move the carriage F into the uppermost position, the gear-wheel I then traveling loosely over the rack J. The operator then throws the lever Q into ahorizontal position, so that the pawl O engages the gearwheel I, as previously described, and as the entire weight of the said carriage and its contents now hangs on the rack J, the latter slides downward until the lower dog N is below the top of the head-block A, thereby permitting the log to be rolled onto the headblock in the usual manner until it rests against the outside of the projection C When the log has been rolled on the head-block, the operator raises the lever Q into a perpendicular position, so as to disengage the pawl 0 from the gear-wheel I, thereby releasing the rack J from the Weight of the carriage F, so that the said rack slides upward by the action of the spring K and movesthe lower dog N, with its point N, into the log from underneath. At the same time the operator lets the carriage F slide downward by its own weight, so that the point G of the upper dog G engages the log from the top. The operator then swings the lever Q downward into about the position shown in Fig. 1, so that the gear-wheel I is turned in the direction of the arrow at, thereby exerting the upward pressure against the rack J, at the same time causing the downward sliding of the carriage F, whereby the points G and N of both dogs G and N are moved toward each other and pressed into the log, so that the latter is securely held in place.

It will be seen that as the lower dog N is supported on the rack which supports the carriage carrying the upper dog and is yield in gly mounted on the spring K, it follows that in case the saw strikes knots or crooks the log can yield, at the same time being securely held in place by the two dogs.

It will further be seen that when the operator desires to release the points G and N of the dogs G and N from the log, the operator moves the lever Q upward, so that the gear-wheel I travels in the inverse direction of the arrow at and moves the rack J downward and the carriage F upward, thereby withdrawing the points of the two dogs from the log.

When the operator desires to grasp the cant or squared log to be sawed up to the last board, he moves the handle E of the lever E down, so that the frame 0 slides to the right until the points of the dogs G and N project only three-quarters of an inch into the timber. The operation of (logging the cant is then the same as for the log.

When the lever Q is moved upward to disengage the points G and N of the two dogs G and N from the log, the cam S presses on the releasing-arm T, so that the end T of the latter engages the rim of the log alongside the point G, so that the latter is easily withdrawn.

Having thus fully described my invention, I claim as new and desire to secure by Letters Patent- 1. The combination, withthe frame, of a vertically-reciprocatin g rack-bar thereon carrying the lower dog and having a free upward movement beyond that required to bring the said lower dog into engagement with the log, with a carriage mounted on the frame and having a gear engaging the rack to raise and lower it, and means for locking the gear to the rack, whereby if an obstruction on a dogged log strikes the saw-collar and causes the log to rise, the rack with the two dogs will yield upwardly, substantially as set forth.

2. In a saw-mill dog, the combination, with a frame and a vertically-sliding spring-sup ported rack supporting the lower saw-mill dog, of a gear-wheel in mesh with the said rack and a carriage mounted on the frame and carrying said gear-wheel and supporting the uppermost dog, substantially as shown and described.

3. In a saw-mill dog, the combination, with a frame and a vertically-sliding spring-supported rack supporting the lower saw-mill dog, of a gear-wheel in mesh with the said rack, a carriage mounted on the frame and carrying said gear-wheel and supporting the upper dog, and a pawl and lever for turning IIG the said gear wheel, substantially as shown I and described.

4. In a saw-mill dog, the combination, with a frame and a vertically-sliding spring supported rack supporting the lower saw-mill dog, of a gear-wheel in mesh with the said rack, a carriage mounted on the frame and carrying said gear-wheel and supporting the upper dog, a pawl and lever for turning the said gear-wheel, and means, substantially as described, for disengaging the said pawl from the said gear-wheel, substantially as shown and described.

5. In a saw-mill dog, the combination, with a yieldinglymounted rack supporting the lower saw-mill dog, of a gear-wheel in mesh with the said rack, a carriage carrying said gear-wheel and supporting the upper dog, a pawl and lever for turning the said gear-wheel, means, substantially as described, for disen gaging the said pawl from the said gear-wheel, and a releasing-arm held alongside the uppermost dog and adapted to be actuated by the said lever, substantially as shown and described.

6. In a saw-mill dog, the combination,with a standard and a vertical frame adjustable horizontally thereon, of a vertically-sliding carriage mounted on and carried by the frame, a dog secured thereto, a gear-wheel mounted on the said carriage and provided with an operating-lever having a pawl engaging said gear, a vertically-sliding rack on said frame and engaged by said gear, and a dog on the lower end of the rack, substantially as set forth.

7. The combination, with the frame, a vertically-sliding rack thereon provided with a dog, and a spring secured at its upper end to 0 the frame and at its lower end to a projecting part at thelower end of the rack to support the rack, of a vertically-slidin g carriage on the frame provided with a dog and means for locking the said carriage to the rack to yield therewith, substantially as set forth.

8. The combination,with the frame having vertical guideways, a rack having a free upand-down movement only in the frame be tween said guideways and carrying the lower dog, of an upper carriage mounted to slide vertically on-said guideways in either direction and held thereby from lateral movement on said frame, an upper dog carried by said carriage, agear also mounted on the carriage and meshing into the rack, and an operatinglever provided with a pawl engaging the said gear, whereby the rack and both dogs will be permitted to simultaneously yield vertically, substantially as set forth.

9. In a saw-mill dog, the combination,with a carriage and a dog secured thereon, of a gear-wheel mounted to turn in the said carriage, a lever fulcrumed on the shaft of the said gear-wheel and carrying a cam, and a releasing-arm pivoted on the said dog and extending in line with the latter, substantially as shown and described.

MARCUS E. BENSON.

Witnesses: VoLNEY D. GoRHAM, J. B. THORNTON.

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