US288510A - Drilling-machine - Google Patents

Description

(No Model?) GE C. TAFT. DRILLING MAGHINL O.

Platen'ted Nov. 13, |1883.

N. PETERS. Fnnlu-Lilhognphnr. washington: |J,C4

i UNITED STATES `PATENT OFFICE.

GEORGE c. Terr, or woEcEsrEn, MASSACHUSETTS.

D-RILLING- MACHINE,

SPECIFICATION forming part .of Letters Patent No. 288,510, dated November I3, 1883.

Application filed June 1, lEQ.

To a/ZZ whom it may concern: l

Be it known that I, GEORGE C. TAET, a citizen of theUnited States, residing at Worcester, in the county of Worcester and State of -Mas sachusetts, have invented a new and useful Improvement in SelfFeeding Drills, of which the following is a specification.

My invention relates to that class of selffeeding drills known as horizontal,77 and has for its objects to aiiord facilities for adjusting the feed,7 to provide `a quick return motion of the drill, and also to securely fasten the slidinglrest atthe bed.

The accompanying drawings represent a drill embodying my invention, in which Figure l shows a front elevation of the drill; Fig. 2, a sectional view of the `main operating parts; Fig. 3, a detached view ofthe feeding device; Fig. 4, the sliding key or spline; Fig. 5, "a secf tional view of the sliding rest.V

Similarletters refer tosimilar parts through out theseveral gures.

The standAsupports the rotating drillspin dle D, and from its base extends the bed B, which carries the sliding rest C. The drill-l spindle D is inclosed by the screw E, which, working in the nut E, imparts a feeding inotion to the drill-spindle D. Rotary motion is given to the drill-spindle D" by thev crank K; The eccentric L is afliXed to the drill-spindle D and imparts a vibrating motion to the lever H, the pivotal bar 7L sliding into the base of the stand A as the drill-spindle and its connected mechanism advance. The upper end of the lever H carries the short lever I, pivoted at I', and having at its upper end the actuating-pawl G, which, engaging with the teeth of the ratchet-wheel F, gives an intermittent rotary motion to the attached screw E, and` accomplishes the feeding 7 of the drill-spindle.

Upon the upper end of the lever H are two lugs, d and f, projecting at right angles to the plane of its vibration, and at a sufficient distance from the secondary lever I to allow the lever I to vibrate between the two lugs at each vibration of the lever H, and consequently impart no motion to the pawl G, the vibration of H being neutralized by the vibration of the lever I. In the lug f, I place the adjustingscrew g, which maybe advanced far enough (No model.)

'to completely check the vibration of the lever I on the pin I, when the two levers H and I will vibrate together and the pawl G be made to pass over Several teeth of the ratchet-wheel, thus giving the maximuml amount of feeding motion to the drill-spindle desired, and by changing the position of the screw any variation in the amount between these two limits may be obtained.

In a suitable socket I place the Spring @,acting against the lug d, and this spring should only be strong enough to hold 'the lever I -against the screw g when no resistance is oifered, the spring being easily compressed at each forward motion of the lever` H without imparting any motion to the lever I,pawl G, and ratchet-wheel F `until the lug d strikes against the lever I. This is necessary, for if the spring is stiff enough to move the lever I and impart motion to the ratchet-wheel,there by feeding the drill-spindle while the drill is at work, the two levers H and I then become practically rigid, and move together, thereby preventing any adjustability of the feed by the screw g. Nor do I claim the use of asecondary lever attached to the vibrating lever and actuated by a spring instead of a driving-lug,

the spring being stiff enough to operate the ratchet against the ordinary resistance in drilling, for` such a construction was shown and described in Letters Patent granted to me March 24, 1857, No. 16,900, in which the force applied to the ratchet by the pawls was measured by the elasticity of the spring, which mightbe varied by means of an adjustable stop against the opposite side of the secondary lever. In my present construction I use a Spring of only sufficient force to carry the secondary lever against the adjusting-screw g, the lug d being used as the driver and the secondary lever vibrating on I between the screw g and the driving-lug d at every vibration of the lever H, the screw g being employed not to increase the force of the spring, but to determine the amplitude of the vibration, and the force applied to the ratchet is measured by that applied to the lever H at the eccentric L.

I accomplish the quick return motion of the drill in either of the two following methods: In the hub of the ratchet-wheel F I place the bindingscrew P, which, through the brass or IOO copper plug P, presses upon the drill-spindle D, so that the spindle and screw E will move together, when, the pawl G being thrown back from the ratchet-wheel and the motion of the spindle D reversed by means of the crank K', the quick return of the drill-spin dle is effected. I also, in some cases, in place of the above, make use of a key or spline, J, sliding in a longitudinal groove or keyway in the drill spindle D, and having the knob J', to afford an enlarged surface for the hand when 'being pushed in, and on the opposite end an enlarged portion, N, forming the shoulder n. In the position shown in Fig. 2 this enlarged end N is inelosed in the annular space M, the hub of the ratchet-'wheel revolving around it; butVv when the quick return of the drill is desired the key J is pushed in, the end Nentering a` rest C, so that the strain of the screw Q will.

come transversely to the base of the rest C, or in the section of greatest resistance, the side being properly strengthened for the purpose of holdingthe screw. The countersunk indentations, by being on the side instead of on the upper face of the bed, and also vby having the side slightly recessed, are protected from dirt and the falling iron chips resulting from the operation of drilling.

I am aware that a sliding rest has been be? fore used, sliding upon a dovetail in the bed, and held by one or more binding-screws, whose strain is thus brought transversely to the bed. Such a construction I do not claim.

I am aware that a vibrating lever has been used to operate the pawl in a feeding device; also, that a secondary pivoted lever has been before used, and such a construction was described in Letters Patent granted to me, and

dated March 24, A. D. 1857, No. 16,900, but for a different purpose, of a different construction in some essential points, and having an entirely different mode of operation. Neither do I claim the construction and operation of the sliding spline or key J for the purpose of effecting a quick return motion of the drillspindle referred to in the foregoingspecification, the same having been made the subject of a separate application.

What I now claim as my invention, and desire to secure by Letters Patent, is-

l. The combination, in a drilling-machine, with the vibrating lever H, actuated by the eccentric L on the drill-spindle, the secondary lever I, pivoted to II at I/, the pawl G, and ratchet F, of the lugs d and f, placed at such distance apart as Will allow the lever I to vibrate between them and impart no motion to the ratchet, the lug f carrying an adjustingscrew, g, having an endwise movement toand from the lever I, and the light spring e between the lever I and actuating-lug d, said spring being only of sufiicient strength to carry the lever I against the screw g during the back-- ward motion of the lever H, allarranged and operating as described, and for the purposeset forth.

2. IIn a drilling-machine, the combination, with the rotating drill-spindle D, of the hollow screw E, inclosing the drill-spindleD and working in the fixed nut E', said hollow screw having abinding-screw, l?, by means of which the rotary motion of the drill-spindle may be imparted to the screw E, thereby -producing a rapid longitudinal movement of the drill-spindle, as and for the purpose set forth.

3. In a drilling-machine,the combination, with the drill-spindle D, of the iiXed nut E and hollow screw E, inclosing the drill-spindle D, and having a binding-screw, I?, and a frietion block or plug, p, all arranged and operating as described, and for the purpose set forth.

Y GEO. C. TAFT.

Witnesses:

R. B. FowLER, A H. M. FoWLER.

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