US1577975A - Safety spindle counterbalance - Google Patents

Description

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" March 23 ,1926.

1,577,975 v D. c. KLAUSMEYER Sm 521mm: copuwsna mucfi Filed April l, 1923 2 Sheets-She't 1 {lyweutoi March 23. ,-1926. *1f577,975

D. C. KLAUSMEYER SAFETY SPINDLE COUNTERBALANCE Filed April 4, 1923 2 SheetsShe'e' 2 20W a y I Qbvwentoz @31 awe mum:

Patented Mar. 23, 1926. v

UNITED STATES PATENT. OFFICE.

DAVID C. KLAUSMEYER, OF CINCINNATI, OHIO, ASSIGNOR TO THE CINCINNATI BICK- FORD TOOL COMPANY, OF CINCINNATI, OHIO, A CORPORATION OF OHIO.

SAFETY SPINDLE GOUNTERBALANCE.

Application filed April 4, 1923. Serial No. 629,852.

To all whom it may concern:

Be it known that I, DAVID 'O. KLAUs- MEYER, a citizen of the United States, and residing at Cincinnati, in the county of Hamilton and State of Ohio, have invented a new and Improved Safety Spindle Counterbalance, of which the following specification is a full disclosure.

This invention relates to drilling machines and it deals primarily with the means for counterbalancing the weight of the spindle and its associated elements whereby the spindle may be readily moved up and down for the purpose of feeding'the drill into and out of the work; all While permitting the spindle to rotate.-

Heretofore, it has been usual to employ a weight for the purpose of counterbalancing that ofrthe spindle and it has, accordingly, been necessary to provide space in or adjacent the frame of the machine to ac.

commodate the movement of the weight. Furthermore, when a weight is employed, it has to be of suitable proportions and means must be provided .for so that thepath of the weight will not be in the immediateproximity of the. spindle; all of which. has entailed some structural objections. Furthermore, the employment of a weight does not make it possible easily to adjust the de-' gree of the counter-pull on the spindle to meet any particular circumstances of use.

This invention, accordingly, undertakes to render available a 'very compact and selfcontained arrangement suitable for the suspension of a drill-spindle and in which a weight is dispensed with and its functions performed by a coiled spring preferably located. in an upper portion of the frame away from the working region of the spin- 2 die. Another object of the invention is to combine with the spindle-supporting-means a safety device such that, if the spindle should fail to be supported, the device will operate forthwith to arrest any untoward descent of the spindle.

Another object is so to construct the spring arrangement that the pull on the spindle will be uniform notwithstanding the increase in' the tension of the spring when the spindle is in its lower positions; thereby avoiding an objection heretofore raised to the use of springs due to their inability to exactly counterbalance the spindle in all of its positions.

Another object is to provide a very con-- venient means for adjustin the degree of tension of the spring or for replacing a broken part or for making any other correction necessary to the mechanism. This has always occasioned much trouble in the and in part rendered apparent therefrom in connection with the annexed drawings.

To enable others skilled in the art so fully to apprehend the underlying features hereof that they may embody the same in the various ways contemplated by this invention, drawings depicting a preferred typical construction have been annexed as a part of this disclosure and, in such drawings, like characters of reference denote corresponding parts throughout all the views, of which Fig. 1 is a vertical section taken transversely to that of Fig. 2 showing in sideelevationthe counter-balancing device and the safety catch. Fig. 2 is a vertical section of a portion of a drilling machine embodying this invention showing a clutch ar rangement enabling the drill spindle to begency check to prevent falling of the drill spindle. Fig. 6 is an enlarged fragmentary will be in part indicated in the following-description side elevation of said emergency check and pawl. Referring'to thedrawings, 1 represents a portion of the frame of a drill head which, in this instance, is provided with guideways 2 and 3 to admit of being shifted bodily along a radial arm or other suitable support. This head l'has a vertical hole within which is vertically shiftable a sleeve 4. This sleeve does not rotate but may be translated by means of a pinion 1.7 engaging a rack 16 afiixed-to one side of the spindle. The pinis a front elevation of the-isolated that the power may be engaged with the with the spindle as to receive the weight ofpinion 17 ,the hand-lever 34: may be turned about its pivot thereby'shifting the cam 37 and the pin 38 which controls the clutch. A stop 44: adapted to cooperate with the part 45 on the hand-lever 34; automatically disconnects the power-feed at an adjusted position and a stop cooperating with a shift-key 4:1 accomplishes the same effect at the limit of. the downward stroke of the spindle.

The sleeve 4, which is vertically translatable as aforesaid in the frame 1, carries the spindle 3 which is journaled therein and is restrained against longitudinal movement relative to the sleeve by means of thrustbearings 5 and 14; the former cooperating with a shoulder provided by the spindle and the latter with an adjustable collar 15, as will be understood.

The weight of the parts is sustained or counterbalanced, without interfering with the vertical movement, by means of a flexible connection here shown as a link-chain 30. This chain is at one end so connected the parts and, at its. other end, the chain is connected with a pull-device adapted to ex.- ercise sufficient tension on the chainto counterbalance the downward drag of the spindle and its associated parts. A convenient form of attachment is that shown best by Fig. 1 in which a plate 6 is firmly secured to the upper portion .of the sleeve 4 and this plate has a projecting portion 7, the extremity of which isrbifurcated to straddle a stationary ratchet-bar 11 having ratchet-teeth 13. It will be seen that, by this arrangement, the sleeve and rack attached thereto are prevented fromturning by reason of the engagement between the projecting portion 7 and the stationary ratchet-bar 11.- Heretofore the sleeve has been restrained from turning by a stationary projection which, so to speak, had a movement along the sleeve during its rise and descent. Bv virtue of the present arrangement, the sleeve is thus made available for the use of an additional stop which is complementary in action to theabove described stop ,40. It willbe understood that,

" when the spindle ,is merely reversed in direction of rotation,-its direction of feed is likewise reversed and the effect of stop 55 is to prevent the spindle from being overfed upwardly. .In prior constructions, the

7 and is urged by a spring 10 towards the ratchet-teeth 13; the object being to effect an immediate and automatic engagement between the pawl 9 and the ratchet-bar 11' in the event that the tension connection 30 either breaks or, for some reason or other, fails to be pulled upwardly with a force sufficient to sustain the weight of the spindle and sleeve. embodiment by providing the pawl 9 with a short arm to which is pivotally attached the lower end of the chain 30. Therelation between the pivot 8 and the point of attachment of the chain is such that when the chain exercises suflicient pull it will hold the pawl 9 into its retracted position and out ofcngagemcnt with the teeth'13. If the tension should be insufiioient, however, the spring 10 will be enabled to act and the pawl This is accomplished, in this 9 will prevent any" downward movement of the sleeve 4. It will beseen that this safetycatch arrangement is equally applicable whether the tension ,on the chain 30 be created by an ordinary counterbalancing weight or by the compact sprmg-mechamsm constituting another characteristic of this invention and which will now be described.

Preferably the axis of the pin 46 is normally offset with relation to the axis of the naled in an upper portion 22 of the frame is a stud 23 which, at one end carries a worm 21 permanently in mesh with the' worm-Wheel 20 and. this stud 23 may be turned by hand by applying a wrench to the squared end 31; thereby enabling the angular position of the shaft 18 to be regulated from the point 21. This being an irreversible drive, .it will be apparent that any tendency'of the shaft 18 to turn will be restrained by the worm 21 in allpositions, although any rotation of the stud 23 will at once effect a corresponding movement in, the shaft 18. The purpose of this arrangement is to enable a counterbalancin -spring to have its tension adjusted to. any desirable degree. This spring is shownby Fig. 3 and i attached to the shaft 18 by means of a pin mg elements such as the Weight heretofore employed. Also, the invention presents a 19. The spring 24 is contained within .a rotatable housmg 26; it bein attached thereto-by means of a hooked en 25 engage ing a slot in the peripheral Wall of the housing, as shown by Fig. 1. The housing 26 is also attached to a member shown by; Fig.

4'which is in the nature of a fusee and on the periphery of which winds the chain 30. The periphery of the fusee 27 provides a shallow groove 28 and this groove is of spiral formation so that it progressively 1nci'eases in distance from the axis of rotation of the fusee. The chain is attachedat one end to the end of the groove 28 which is most remote from the axis of rotation, as by means of'a in 29. f

It will be perceived that, in consequence of this arrangement, as the spindle is lowered, and as the spiral spring 24 increases in tension, the-po1nt on which the chain leaves its drum willbe more and more remote from the axis of rotation; in other.

words, the leverage efi'ect will progressively decrease as the tension of the .spring increases and conversely. In this manner, the chain 30 is subjected to a constant tension in all positions of the spindle althou h the spiral spring has its tension increase as it becomes wound more and more tightly.

It will be perceived that this invention provides a very compact self-contained arrangement, eminently suitable for drilling machines, and which removes from the proximity of the spindle any space occupydegree of safety not heretofore attalned in asmuch as it is impossible for the spindle or sleeve to fall even though the means normally supporting it should fail and, further more, in the event of such a failure, it is'a very simple matter to make repairs inas-- much as the connections are immediately accessible and such connections may be estabished undereasy working conditions, to wit, when there is no tension on any of the parts; the means for re ulating the tension .of the spring being capa le of reducing that tension to zero or of increasing it to any desired amount after the connection has been established.

Without further analysis, the foregoing will so fully reveal the gist of thisinvention that others can, by applying current knowledge, readily adapt it for various essential characteristics of either the generic in case said counter.-

pally-movable spindle; quick-traverse means therefory. a fusee connected -to carry the weight of said s'pindle;.a coiled spring exer-v cising a counter-pull on said fuses; and a safety-latch means for said spindle normally held inoperative'b the connection between the fusee and spmdle and adapted automatically to arrest the descent of said spindle ull should cease.

me combininga spindle; a sleeve having a rack; a pinion engagin said rack; means for turnin said pinion eit er manually to effect a quic -traverse of said sleeve or y power to feed said sleeve; a coiled-spring for counter-balancin said parts; a planar compensator intervening be- 1 2. A drilling-mac tween said sprin and said parts for rendersleeve; a coiled-spring for counter-balancmg said sleeve and spindle; a planar pullequalizer intervening between said spring and said sleeve for rendering uniform and maintaining in the same plane the pull of saids ringv on said spindle; manual means for a justm the normal tension of said spring; a me carried by said sleeve; means cooperating with said rack for shifting said sleeve either quickly manually or slowly by power; and 21 safety-catch comprising a spring pressed pawl 'mounted'directly on said sleevev to cooperatew/ith a fixed rack for automatically arresting the fall of said spindle in'case it should fail to receive suport from said spring, whenever the power eeding means is disengaged;

In witness-whereof, I hereunto subscribev y name. utihzatlons by retaining one or more of the r" a DAVID o. musMEYER.

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