US936870A - Electric drill. - Google Patents

Description

3 BHEETS-SHEET 1.

Patented 0@1..12,19o9.

ELBGTRIG DRILL.

APPLIUATION FILED MAY a, 1905.

Wi 0. DUNTLEY L H. J. KMMAN.

ELECTRIC DRILL.

APPLIOATION FILED MAY a, 1905.

@36pm/QQ Patented not. 12,1909.

3 SHEETS-SHEET 2.

. O yfssfs.- 71( 7 7 74 /NvE/vofes F y v Y n y r @y @WM :7M/1 NORA/Ens W. 0. DUNTLEY L H. J. KIMMAN. BLEGTRIG DRILL.

APPLICATION FILED MAY s, 1905.

9861,87@ l Patented Oct. 12, 1909.

3 SHEETS-SHEET 3.

.7429 AHORA/Ens currar) STATES PATENT carica.

WILLIAM 0.` DUNTLEY,OF CHICAGO, ILLINOIS, AND HRY J. KIMMAN, OIE CLEVE- LAND,

JERSEY. l

l To all whom it mcy-concern:

` Y. is to produce an etiicient and reliable tool or drill of `this character, chierI among whose advantageous features is a provision for preventing 'overloading of the drill, the result being accomplished, inthe present instance,

by so constructing and arranging the driving connection between the iiiotor and the tool spindle that such connection is rendered inoperative -whenthe drill `becomes overloaded, With the. result that the drill is `stopped without interfering with or stopping the electric motor, which continues to run Without effect upon` the tool spindle or drill.

Our invention relates, to other -advanta-l geous features,'such as a novel and original` construction of switch device for the motor jcir'cuit, aswell as a novel and original form ,f of force feed device for the tool or machine.

In lthe d rawings,'ld`igure 1 is a longitudil nal sectional elevation oii7 an electric vdrill embodying our'invention'; Fig. 2 a plan view thereof; F lgs. 3 and 4 details of the switch;

Figa 5 an elev-ation of the brush holder, and

Figs. 6 and 7 sectional views yillustrating :modified vforms of gearing.

xfReferring to the particular embodimentof *our invention as herein illustrated. the elec- 'I tric drill comprises a main casing' 1. within which is'arranged an-electric motor 2, the

, lcasing "preferably forming the Aiield frame of such motor.

i Moreover, by preference, tlie casing is providednwith a series of tianges lor ribs 3, for the purpose lof'lradiatng the heat. that may possibly be generated and to assist the fan device -in'co'oling `the motor, as hereinafter described; lBy preference, the upper portion of tiie'casin'g is substantially cylindrical, but is outwardly'flared at its lower e "end andprovided at itsextreme end with a Range-4, in order that the gear casing 5 may specification of 'Letters Patent.

-ing a Morse taper.

OHIO, 1ASSIGNORS,I BY DIRECT `ANB MESNE ASSIGNMENTS, TO CHICAGO PNEUMATIC TOOL COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION 0F NEW'V nimse'rme imiLL.

Patented Oct. 12, 1909.

a, i905. serial no. 258,675.

be secured to the main casing of the machine or drill. Between this main casing and the gear casing is clampeda lower head or diaphragm 6, inl which is arranged the lower bearing 'i' of the armature shaft 8 of the electric in otor, which bea-ring may be of suit.- able construction, but herein showneas a ball bearing.y Anotherhead 9 is arranged at the upper end of the main casing of the machine and the saine is in the present instance and 'by preference, east or formed integral with the main casin rllhis upper head is provided witli a suitable bearing 10, in the present inst-ance a ball bearing, for the purpose of journaling the upper end of .the armature shaft. The lower end of the armature shaft extends through its bearing and through the diaphragm or lower head 6 and is formed as or provided with a pinion 11, which lis ar-I ranged to mesh with a train of gears, Jfor the purpose of transmitting the motion or rotations ot' the armature to the tool socket or spindle 12, which receives theshank of.

the drill or other working tool in the well f known manner. ln' the present instance, the

particular forni of gearing employed and' herein `illustrated is of the planetary type comprising essentially two gears or pinioiis 13 revolving in connection with a circular rack 14. arranged in asocket in the upper end of thejgear casing. These revolving gears are mounted to rotate-freely on the vertical studsl, which are in turn secured upon the revolving yoke or gear frame 16 pinned or otherwise secured to the tool spindle .12. lu the present instance, this tool spigdle is provided with a tool socket 17 hav- As illustrated in Fig. 1 the revolving gears properdo not-(imesh with the circular rack 14, but the saine are provided with hubs 18 formed as pinions for directly engaging with the circular rack 11i.

it will be understood that if the machine or drill should be constructed as just described, the same is liable to be overloaded from several causes, such its the use of a drill -largertl'ianl the capacity or power ot the machine, o-r by too great pressure or feed eX- erted on the tool or drill, with the result that owing to the consequent stoppage or slowing down ot the electric motor, the latter would be supplied with such an amount/oi/ out the armature windings. To overcome this objection of overloading, preferably without interfering with the motor o1' its current, is the principal feature of our present invention and to accomplish this result, we provide means whereby the gearing becomes inoperative when the load on the working tool reaches or exceeds a predetermined amount. In the present instance, this result is brought about through the medium of the circular rack 14, which is nor- 'mally in a fixed or stationary position so long as the predetermined load 1s not reached orv exceeded, but which is adapted -to slip Within its socket in the casing, whenever such predetermined load is reached or exceeded. In the normal operation the circular rack is in fixed positlon, as stated, and the revolving gears 13 are consequently enabled to transmit the motion of the motor to the tool spindle, but obviously when the predetermined amount of load is reached or exceeded and jincreased pressure brought to bear by thefv revolving gears or pinions against the rack the latter will slip and be rotated, withthe result that the tool spindle will stop, while theelectric motor will continue to run. In the present instance, the

. driving connection between the tool spindle and themotor may be considered a frictinal drive in connection with gearing, the arrangement being such as hereinafter described, that the amount of friction or frictional resistance may be adjusted in degree at the will of the operator, so that the predetermined amount of load may be varied'as described.

Referring to the construction as herein illustrated, the circular rack 14 coperates with means for applying pressure or frictional resistance thereto, such means comprisin a pressure applying ring 19, arrange theretoward with yielding pressure by means of a series of spring pressed studs 20. Each of these studs projects upwardly through the upper end of a spring case 21 formed on the gear casing and containing a spring 22 ressing against the head of the stud 20 an also against a nut 23 arranged to screw upon the spring case for the purpose of varying or adjusting the tension of the spring and` consequently varying or adjusting the amount of the frictional resistance of the curved'rack 14. In order to receive the upward thrust on the circular rack we'provide an abutment 24, which is in theforin of a ring secured to the gear -casing. By preference, we provide 'between the rack 14 and the two rings 19 and 24, resistance rin 25 of suitable material such as fiber.

vide a proper and uniform amount of resistance, and moreover cannot be crushed or become cut. The load which can safely be below the circular rack and held e'prefer to employv these fiber rings, inasmuch as the same pro-' amount of load is still carried by it, because of the fact that it is at Such time, rotating the rack on which the frictional resistance is constant. Consequently, the motor carries the predetermined amount of load, but is relieved of the excess load.

IVe do not limit our invention to the speciic character ofgearing illustrated in Fig.l

l, nor to the specific manner or meansfor obtaining the results hereinbefore referred to, inasmuch as the same results could be accomplished by other specific means without departing from the spirit of our invention, and

vrun wild, inasmuch as the predetermined furthermore, our invention is applicable in respect to other constructions of gearing, as

illustrated in Figs. 6 and 7 hereinafter described.

Referring next to the switch device, as

`V,illustrated 1n general in Fig. 1 and inl detail in y.Figs 3 and 4, the same comprises two sprl terminals26 arranged in the motor circuit and supported by the insulating block 27, fastened, 1n the present instance, on the upper surface of the lower head lor diaphragm' 6. The connection between these terminals is under thecontrol of two keys or buttons 28 and 29, which are arranged to project from Athe upper surface of an extension 30 of the main casing and on either 'side of one of the grasping handles 31, which, as indicated in` Fig. l, is secured into one side of the main casin The lower end of the button .29 is provided with means for electrically connecting the two terminals and, in the present instance, such means consilsts of an anti-friction roller 32 of conducting material, with the result that when the button 28 is in its innermost position, as illustratedin Fig. 4, the motor circuit is closed,

the other button 29 being at this time in its outermost position. For the 'purpose of holding the buttons with a yielding pressure inone posit-ion or the other, we provide suit able means such as the lever 33, rocking on the axis 34 intermediate its length with its ends bearing in and engaging the side recesses 35 and 36'of the buttons 28 and 29, respectively. This lever is provided with al depending larm or finger 37, in whose path of movement is interposed the double bevv. eled or wedge-shaped end or head ofan uping the buttons in their relative position, to

which they have just been moved. The result of this movement of the buttons is to open the circuit by removing the roller 32 from its cooperative relationship with the terminals. By preference, the buttons 28 and 29 which, as indicated in Fig. 4, have their bearings in the top of the extension 30 and also through the two lugs 4() and 41 tlierewithin, are arranged or disposed in a plane parallel to the armature shaft and ooni sequently to the line of thrust vwhich is directly along the central axis of the tool or machine and through the axis of the tool spindle. movable elements of this switch, that is the buttons, is in the direction of the longitudi- 'iial axis of the machine or drill and transverse to the longitudinal axis of the handles, with the result that the switch may be operated aiid/ the drill thereby controlled without disturbing the position thereof with relation to the work, which might otherwise result when the tool is held simply by the grasping hands. Moreover, the buttons are arranged on either side of the handle so as to be easily controlled by the operator.

Referring next to the force feed device, the same comprises, iii the present instance, a yoke or U-shaped frame 42, whose parallel members are screw-threaded on their outer edges and enter the interior of the main casing through the top thereof. The cross piece of' this yoke extends diametrically across the top of the machine` or drill Aand is v provided at a' point coincident with the longitudinal axis or line of thrust of the machine or drill, with a centering point 43. For the purpose of operating the yoke and thereby changing its position with relation to the main casing to bring about a force feed,

we provide a pilot wheel 44 internally screwthreaded to engage the screw-threaded arms or members of the yoke 42, the yoke being moved up or down, that is in or out with respect to the main casing accordingly as the -ivheel is moved iii one direction or the other.-

For the purpose of maintaining the .pilot wheelin fixed posit-ion with respectrto the longitudinal axis of the tool or machine, we provide a retaining ring or cap 45, which is secured in suitable manner to the upper surface of the end head 9, which projects above the top plane of the main casing proper, the wheel operating between such ruig. or cap 45 rlhe direction of movement of the.

and such to plane or edge of the main casing, as clear y indicated in Fig. 1. This construction not only provides an efficient and serviceable force feed device, but also serves as a grasping handle when the yoke is moved outwardly sufficient to permit the hand of the operator to grasp the cross piece of the yoke, such grasping handle, or rather the so called grip, being advantageous, especially inv `reaming. opera-tions and where it is desirable that the operator shall hold the tool by one of the regular handles and also by a grip which is in a different position or location than -the other regular grasping handle of the machine. y

'As illustrated in F 1, the machine or drill may be provid with two grasping handles, the handle 31 already described, and also the handle 46, through the latter of which the leading-in wires or cable 47 of the motor circuit may be passed. As seen in Fig. 1, these wires connect with a fuse 48 which 1s arranged opposite one of the openings 49 in the outwardly flared portion of the main casing. 1, with the result that the fuse may be easily and conveniently removed and a new one substituted. rlhese openings 49, how- .I

- ever, are primarily air ports for the passage' of air and the same coperate with a fan device for forcing a circulation of air through the casing and among the elements or inembers of the motor, that is to say, our motor is air cooled. Asherein shown, thefan 5() is secured to the lower bearing 51 on the arma.- ture shaft 8. The openings 49 are for the entrance or exit of the air accordingly as the `blades of the fan are so positioned as to force -or draw the air through the motor casing.

The gear casing is by preference partially or wholly illed with a suitable lubricant, desirably a heavy oil or a so called compression grease, or the like,'and for the purpose of introducing such lubricant within the gear casing,1 provide one or more openings closed by screw plugs 5a.

As hereinbefore suggested, the type of gearing in which my invention may be embodied may partake of differentv forms, as illustrated in Figs. 6 and 7. Referring first to the modification of Fig. 6, the armature pinion is operatively connected, as heretofore, with revolving pinions, butyin the present instance, such pinioiis marked 52 directly gengage or mesh with the rack 53, instead of being operatively connected therewith, throu h pinions ontheir hubs,;a s in Fig. 1. In this modification, the-retaining ring 24 is dispensed with and the upper friction ring 25v is clamped between the head or diaphragm 6 and Vthe upper edge of the rack. In other respects, the construction and mode of operation is substantially the same as the device illustrated in Fig. 1. Referring next to the second modification illustrated in Fig.v

-7, the armature pinion meshes withl the two revolving pinions 54, which engage a permanently fixed circular rack 55 secured in a socket on the lower edge of the diaphragm 6. These revolving pinions rotate freely on studs 56, secured in the yoke 57, whose hub is journaled on the upward extension 58 of the tool spindle. rllhis hub is formed as a pinion 59 engaging the two `revolving pinions 60 mounted on the studs 6l of the revolving yoke 62, which is directly fastened or keyed to the tool spindle. rlhese revolving pinions 60 mesh with the circular rack 63, which is provided with the friction rings 64, arranged at the opposite edges thereof. The tensionapplying ring presses against the upper edge of the rack and is held theretoward by means of the spring pressed studs 66. rllhese studs are arranged in a case 67 formed in the diaphragm or head 6, in which screws the nut 68, for the purpose of adjustinvr the ten sion of the spring 69 therewithin. lhis form of gearing, whichv may be considered a double planetary type, operates in the same manner so tar as the result .of preventing overloading is concerned. i

rlhe brush holder in the present instance I is constructed as illustrated in Fig. 5, which provides a sim le arrangement, although other forms of crush holders may be employed. The brush holder comprises essentially a plate 70 secured to the upper head or end plate of the casing and having anl eX- tension (1 provided with an opening to receive the brush (2, which is forced head on against lthe commutator 73 of the motor, with a yielding resistance by mea-ns of the two liat springs 74, whose ends are fastened in the posts 75 rising from the plate 70.

We claim:

l. In an electric. drill, the combination, with an electric motor and a tool spindle, of a train of gearing between said motor and tool spindle, oneof the members of the train being a rack normally stationary. but arranged to rotate and thereby destroy the operating connections between the motor and tool spindle when the load oni the latter reaches a predetermined amount.

2. In an electric drill, the combination,

`with an electric motor and. a'tool spindle, ofplanetary gearing forming the operat1ng` connection between the motor and spindle,

one member of the train being arranged. to

become inoperative when the load reaches a predetermined amount.

3. In an electric drill,.the combination, with an electric motor anda tool spindle, of planetary gearinglforming the operating connection between the motor and splndle, and comprising a rack and pinions, said rack being normally stationary but arranged to rotate when the .load `on the tool splndle reaches a predetermined amount.

4. In an electric drill, the combination,y

amount to resist a @saam ot planetary gearing forming the operating connection between the motor and spindle and comprising a rack and pinions, and a casing or support with which said rack has rictional re'slstance up to a predetermined equaling the rictional resistance with said ring.

6. ln an electric drill, 'the combination, with an electric motor and a tool spindle, of planetary gearing forming the operating connection between the motor and spindle predetermined load on they and comprising a curved rack and pinions,

and means for clamping said rack to resist a predetermined'load onthe tool spindle.

hln an electric drill, the combination, with an electric motor and a tool spindle, oi. planetary gearing forming the operating connection between the motor and spindle and comprising a rack and pinions, and

means for imparting a predetermined iricl tional resistance to the rack to resist a predetermined load on the tool spindle.

8. ln an electric drill, the combination, with an electric motor and a tool spindle, of train of gearing orming the operating connection between the motor and spindle, one of the members of the train being a rack, and means for imparting to the rack a resistance adjustable in degree.

9. lin an electric drill, the combination, with an electric motor-and a tool spindle, of planetary gearing forming the operating connection between the motor` and spindle, one of the members of the train being a rack, andm'eans for im arting thereto a frictional resistance adjusta le in degree to resist any predetermined load on the tool spindle.

10. In an electric drill, the combination, with an electric motor and a tool spindle, of planetary gearing forming the operating connection between -the motor and spindle and comprising a rack and pinions and springsv impartmg ayfrictional resistance to the rack. 11.

11. In an electric lthe combination, with an electricy motor anda tool spindle, of, planetary gearin'gvformi'ng the operating connection between' the'motor. and spindle and comprising a rack and pinions, sprin s imparting a frictional resistance to the ra vvarying the tertsionv of the and .means for sprmgs.

12. In an electric with anelectric motor and a tool spindle, of

drill, ,the combination,

v ovith an elec-tric motor and a tool spindle, of

planetary gearing forming'the operating connection between the motor and'spindle and comprising a lrack and pinions, a friction ring bearing against the rackv and a series of spring-pressed studs bearing j against the ring to hold the rack with a predetermined frictional reslstance.

15. In an electric drill, the combination,

with an electric motor and a tool spindle, of

planetary gearing forming theA operating connection between the motor and spindle andcomprising a rack and' pinions, a friction ring. bearing against the rack, a series of spring-pressed studs bearing against the ring to hold the rack with a frictional resistance, and means for adjusting the degree of tension exerted by such studs.

16. In an electric drill, the combination,-

with an electric motor and a tool spindle, of planetary gearing forming the 'operating connection between themotor and spindle and comprising a rack and pinions, a casing or support having a socket to receive such rack, and means for holding said rack therein .with an adjustable frictional resistance.

17. In an electric drill, the combination,

with a casing and with the electric motor armature arranged therein, of a fan within the casing which is provided with openings for the passage of air, and fuse arranged 1n the electric motor circuit and located adjacent one of said openings for ready inspection and replacement.

18. In an electric drill,'the combination,

with'a casing and with the electric motorarmature arranged therein, of a force feed device comprising a screw-threaded yoke, and a screw-threaded wheel or ring engaging said yoke and bearingagainst the casing. 19. In an electric drill, the combination, with a casing and with the electric motor armature'arranged therein, of a force feed device comprising a yoke whose parallel members are screw-threadedl and enter the casing, and a screw-threaded ring engaging said yoke and bearing against the casing.

20.111 an electricdrill, the combination,

, with a casing and .with the` electric motor armature arranged therein, of a force feedv device-comprising a U-shaped frame whose.

to its normal position.

parallel screw-threaded members enter the casing and whose cross-piece extends diametrically across the outer end of the casing, and a screw-threaded ring engaging `said yoke and bearing against the casing.

21. In an electric drill, the combination, with a casing and with the electric motor armature arranged therein, of a force feed device comprising a yoke whose parallel members are screwthreaded and enter the casing, said yoke having al centering point, anda screw-threaded ring or wheel engaging said yoke and bearing against the casing.

22. In'an electric drill, the combination, with a casing and with the electric motor armature arranged therein, of a force feed device comprising a screw-threaded yoke, and a screw-threaded wheel engaging said yoke and rotatably mounted on the casing and having a fixed relation thereto with respect to the longitudinal axis thereof.

Q3. In an electric drill, the combination, with the casing and the motor armature therein, -of an electric switch for controlling I said motor, and grasping handles connected 'with the casing, said switch having contact parts within said casing and an actuating part on the outside thereof adjacent a handle and within reach of the operators hand.

24. In an electric drill, the combination with the casing and the motor armature therein, of grasping handles on the casing, an

elect-ric switch for controlling said motor,

said switch comprising Contact parts within said casing, a button for operating said contact parts, and another button for restoring said parts to their normal condition, said buttons projecting through the casing to the ilitside thereof and adjacent one of .the han- 25. The combination with an electric drill, of grasping handles on the-casing, a controlling switch. therefor, said switch being mounted upon said drill, and comprising contact parts, a part adapted to be inovedto operate said contact parts, and a part adapted to be moved to restore' said operating part 26.111' an electric drill, the combination with the casing, and the motor therein, of a handleon said casing, and a switch for controlling said motor, said switch being mounted on saidvcasing, and having two actuating parts, one located on either side of said` handle.

27. In an electric drill, the combination with `the casing, and the motor therein, of a handle-secured on said casing, and a switch for cont-rolling said motor, said switch being mounted on said 'casing and having an operating button, and a. restoring button, said buttons being arranged for movement in the direction ofthe longitudinal axis of the drill, and being located one on either side of said handle. V

'rection of the longitudinal axis of the motor,

whereby the drill may be controlled Without disturbing its position with relation to thei AQwork.

Q9. In aii electric drill, the combination (with the casing and the motor therein, of a handle secured to the outside of the casing, andan electric switch for controlling said motor, said switch having its contactparts within said casing, and its actuating part or button projecting through the caslng in proximity to said handle, said button being movable substantially in the direction of the line of thrust of the drill.

30. In an electric drill, thecombination with the casing and the motor therein, of a handle secured to the casing, and an electric switch for controlling said motor, said switch comprising contact parts within said casing and an actuating part outside of said casing in proximity to said handle, said `iactuating part being so disposed/as to require a movement transverse to the longitudinal axis of said handle to actuate the same. 31. In an electric drill, the combination with the casing'and the motor therein, of an electric switch for controlling said motor, said switch comprising'contactparts and an actuating part, s/aid actuating part being located upon the outside of said casing and being so disposed as to require a movement thereof inthe direction of the longitudinal axis of the motor to operate the switch.

32. In an electric drill, the combinatioir with the casing, and the motory therein, of

a handle secured to the outside of said cas-- ing, an electric switch for controllin the circuit of saidlmotor, said switch eing mounted on said casing and having two actu ating parts arranged in proximity to said handle, said arts being movable substantially in the direction of -the line of thrust of the drill,'one of said actuating partsy operating to make the circuit and the other' to break the circuit. p

33. In an 'electric drill, the combination with the casing, and the motor therein, rof a handle secured to the outside of said casing, an electric switch for. controlling the circuit of saidmotor, contact parts for said switch within said casing, and actuating parts for said switch projecting through,

said casing in proximity tosaid handle, said actuating parts being disposed one on either side of said handle and being arranged to be essere moved in the kdirection 34. 'In an electric drill, the cdrnbination with a casin and a motor therein, of two handles rigid y secured to the outside of said casing at diametrically opposite points, and an electric switch for controlling said motor, said switch comprising contact parts located within said casing,` an actuating key or button coperating with said contact parts, a restoring key or button, and a link connecting said buttons projecting through said casing in proximity to said handle and being so disposed with relation to the drill that their operating movement is in the direction of the longitudinal axis thereof.

35. In an electric drill, the combination with the casing and the motor therein, of a handlesecured on said casing, and a switch or controlling said motor, said switch being mounted on said casing, and having an operating button, a restoring button, said buttons being movable in the direction of the line of thrust of the drill, and means for holding the buttons in one position or the other with a yielding pressure.

36. 'In an electric drill, the combination for controlling said motor, said switch being mounted on said casing, and having an operating button, a restoring button, said buttonsbeing movable in the direction of the line of thrust of the drill, and a springpressed pin. cooperating with said buttons to hold them in one position o1' the other.

37. In an electric drill, the combination with the casing and the motor therein, of a handle secured on said casing, and a switch for controlling said. motor, said switch being mounted on said casing, and 'having an operating button, a restoring button, a connecting rocking lever between-the buttons having a projecting finger, and a spring'- pressed pin coperating with said finger to hold' the lever and the buttons in one position or the other, said buttons being movable in the direction of the line of thrust of the drill.

y WILLIAM O. DUNTLEY. .HENRY J. KIMMAN.

Witnesses to the signature of William O.

Duntley:

' S. E. HIBBEN, H' GERTRUDE C. ARMSTRONG. Witnesses to the signature of Henry J. Kimman: i

J. MILLS, S. R. WALLACE.

looI

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