US2897635A

US2897635A - Drill pointing machine

Info

Publication number: US2897635A
Application number: US622683A
Authority: US
Inventors: Stephanoff Alexander
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-11-16
Filing date: 1956-11-16
Publication date: 1959-08-04
Anticipated expiration: 1976-08-04

Description

Aug. 4, 1959 A. sTEPHANoFF 2,897,635

DRILL POINTING MACHINE Filed Nov. 16, 1956 6 Sheets-Shea?l 1 /Z 3 99 l 7 7485/ 87 135 3 l/r I+ 7g2 8 '1? las 7 84 37 38 /8 36 lo n ol/9 Aug. 4, 1959 A. sTEPHANoFF- DRILL Pomme MACHINE 6 Sheets-Sheet 2 Filed NOV. 16, 1956 (mNm v R.a 6 ww W NA K M y L T mw A S M @A I M y B a A 0 MN www Aug- 4, 1959 A. sTEPHANoFF 2,897,635

DRILL POINTING MACHINE Filed Nov. 16, 1956 6 Sheets-Sheet 3 Aug- 4, 1959 I A. STEPHANOFF 2,897,635

DRILL POINTING MACHINE Filed Nov. 16. 1956 6 Sheets-Sheet 5 Aug. 4, 1959 A. STEPHANOFF DRILL POINTING MACHINE 6 Sheets-Sheet 6 Filed NOV. 16, 1956 IN1/EN TOR. A L 5114/1/05( S f/MMUFF fram/sys I Stte This invention relates generally to grinding or abrading machines, and, more particularly to a machine of this type which is especially adapted to finish grind the points on twist drills, and other similar tools or cutters.

lt is the primary object of this invention to provide an automatic twist drill pointing machine which is adapted to accurately finish grind the points on twist `drills with the proper .angle and clearance and at a high rate of production. The machine of the present invention generally comprises a rotary fixture adapted to carry a plurality of twist drills and to alternately move the drills into operative grinding engagement with a pair of laterally spaced -apart grinding wheels as the fixture is simultaneously rotated and reciprocated, so as to finish grind the pointed end of each of the drills on opposite sides thereof and thus produce an accurately ground and centered point on each of the drills. The drills are fed by a hopper to the rotary fixture and are automatically located, indexed to the proper position for grinding, clamped, ground, and ejected at a highly efficient rate of production.

It is another object of this invention to provide an automatic twist drill grinding machine which is economical of manufacture, simple of structure, durable and compact, and highly efficient in operation.

Other objects, features and advantages of this invention will be apparent from the following detailed description and appended claims, reference being had to the accompanying drawings forming .a part of the specification wherein like reference numerals designate corresponding parts of the several views.

ln the drawings:

Fig. 1 is a top plan View, with parts removed and parts broken away, of a twist drill grinding machine made in accordance with the principles of the invention;

Fig. 2 is a side elevational View of the structure illustrated in Fig. l, taken substantially in the direction of the arrow marked 2, with parts broken away and parts in section;

Fig. 3 is an end elevational view of the structure illustrated in Fig. l, taken substantially in the direction of the arrow marked 3;

Fig. 4 is an enlarged end View of a drill clamping fixture employed in the invention, and showing an air cylinder adapted to position a drill in the fixture;

Fig. 5 is a top plan view of the drill clamping fixture illustrated in Fig. 4, taken in the direction of the arrow marked 5;

Fig. 6 is a plan view of an adjustable eccentric stud used in the drill clamping fixture of Fig. 5;

Fig. 7 is an end view of the eccentric stud illustrated in Fig. 6, taken along the line 7 7 thereof;

Fig. 8 is a side elevational view of the clamping fixture shown in Fig. 4, taken in the direction of the arrow marked 8, and showing the cam locking means for the fixture; Y

Fig. 9 is an enlarged top plan view, partly broken away 297,635 Patented Aug. 4, 1959 l rc and partly in section, of the drill locator means employed in the invention; Y

. Fig. 10 is an enlarged side elevational View of the drill contacting member employed on the drill locator shown in Fig. 9;

Fig. 1l is an end elevational view of a carrier member employed on the drill locator shown in Fig. 9, taken along the line 11-11 thereof;

Fig. 12 is a vertical sectional view of the structureV illustrated in Fig. 11, taken along the line 12-12 thereof;

Fig. 13 is an end elevational View of the structure illustrated in Fig. 10, taken in the direction of the arrow marked 13;

Fig. 14 is an elevational view of the structure illustrated in Fig. 9, taken in the direction of the arrow marked 14;

Fig. 15 is a partial elevational view of the structure' illustrated in Fig. 14, taken along the line 15-15 thereof;

Fig. 16 is a plan view of the cam and cam roller adapted for actuating the drill carrying rotary fixture forwardly and backwardly;

Fig. 17 is an enlarged partial elevational view of the drill ejector structure illustrated in Fig. 1, taken along the line 17-17 thereof;

Fig. 18 is a partial plan View of the structure illustrated in Fig. 17, taken along the line 18-18 thereof;

Fig. 19 is an enlarged partial elevational View of the structure illustrated in Fig. l, taken along the line 19-19 thereof, and showing the rail for actuating the drill fixtures clamping means;

Fig. 20 is an end view of a drill showing the manner in which the -drill locator engages a drill;

Fig. 21 is `a partial elevational view of a drill adapted to be finished ground by the apparatus of the present invention;

Fig. 22 is an end elevational view of the right grinding wheel, taken along the line 22-22 of Fig. 1, showing the position of the drills in grinding one side of a drill point; y

Fig. 23 is an end elevational View of the left grinding wheel, taken along the line 23--23 ofFig. 1, showing the position of the drills in grinding the other side of a drill point;

Fig. 24 is a plan View of a modified grinding wheel adapted for use in the invention;

Fig. 25 is an end view of the structure illustrated in Fig. 24, taken along the line 25-25 thereof;

Fig. 26 is an elevational side view of one of the grindthe drill point during the grinding of the second side of the drill point. i

Referring now to the drawings, and, in particular to Figs. 1, 2 and 3, an illustrative embodiment of the invention is shown which includes a rotary fixture base 10 that is provided on its upper side vwith a horizontally disposed longitudinally extended dovetailed guide 11.

A horizontal carriage or slide 12 is slidably mounted on the lguide 11 with its longitudinal axis normal or at a right angle to the longitudinal axis of the guide=11,.l

The slide 12 is adapted to'be moved on the guide 11 by means of the elongated screw rod 13, the inner end of which is threadably mounted in the slide 12in the usual manner and the outer end of which is rotatably- 3 l mounted in the armv 14 which is xedly mounted, in any suitable manner, as by welding, on the outer end of the base 10.

`-A. supporting bracket 15fis"iixefdly mounted on the outer end of the base 10, by any suitable means,- as by the bolts 16: Fixedly mountedon the bracket 15 is aconventional gear reductionLmeans 17 which is connected to the outer end of the screw rod 13 by means of the coupling 18. Fixedly mounted on the bracket is a constant speed electric'motor 19 which is connected to the gear reduction means 17 by means of the coupling 20. The motor 19 and gear reduction means 17 are adapted to continuously rotate the screw rod 13 so that the slide 12 'will be advanced or retracted along the guide 11 approximately thirty thousandths of an inch per revolution of the screw rod. This will permit the drills to. always move longitudinally of the grinding wheels over a clean part thereof and provide even wear on. the grinding wheels. It will be understood that the movement of the slide 12 could also be regulated in accordance with the movementv of a predetermined number of drills engaging the grinding wheels, and a suitable gear reduction means and constant speed motor could be selected accordingly.

The motor 19 may be reversed at the end of the advanceor retraction travel of the slide 12 by any suitable means, as by the following means. The motor 19 is connected by means of the conductor lines 20a to a usual electrically operated reversing switch 21 which is connected to a suitable source of electrical power indicated by the numeral 22. A first micro-switch 23 is xedly mounted on the base 10 adjacent the rear end thereof and is connected to the reversing switch 21 by the conductor lines 24. A second micro-switch 25 is tixedly mounted on the base 10 adjacent the forward end thereof and is connected to the reversing switch 21 by the conductor lines 26. The

switches

23 and 25 would be set apart a distance equal to the ,desiredy length of travel of the drills lengthwise to the grinding wheels. The

switches

23 and 25 are operated by means of the rigid downwardly extended arm 27 which is xedly mounted on thev adjacent end of. the slide 12, as by means of the bolt 28. The contacting of the

switches

23 and 25 by the

arm

2,7 will operate these switches which in turn operate the motor reversing switch 21.

The slide 12 is provided on 'its upper side with a longitudinally disposed dovetailed guide 29 on which is shdably mounted a second slide or carriage 30 which Vcarries the housing generally indicated by the numeral 351.V Thehousing 31 is swivelly mounted on the second slide 30 by means of the swivel pin 32 (Fig. l) and is andj3, the bolt 33 passes through the arcuately shaped aperture 34 in the bracket 35 which is xedly mounted on the housing 31, and this bolt then is threadably engageable Vin a suitable aperture in the upper side of the slide 30. The housing 31 may thus be adjusted relative to the slides 12 and 30 to provide for different posltions for grinding drills having differently angled points. For example, the drill illustrated in Fig. 2l has an angled point of 59 and so the housing 31 would be set to provide an angle of 59 between the longitudinal axis of the guide 11 and the longitudinal axis ofthe housing 31. This angle is indicated in Fig. lfby the letter x.

The second or upper slide 30 is adapted to be moved on the rst `or lower slide 12 by the following described means. 1 Fixedly mounted on the inner end of the slide 12 is avertically extended arm 36 having a recess 37 on the ,inner side thereof in which is nested one end of av co1l spring 38', and this is best seen in Figs. 1 and 2. The other end of the coil spring 38 is nested in a recess as 39 in ,the inner end of the lslide 30.. The coil spring 38 functions to normally bias or move the slide 30 on the guide 29 toward the outer end or right end of the slide 12V, as viewed in Fig. 3. A drive motor? 4Q is lrxedly l nected at its front end with the motor shaft 43 by means of the coupling 47. A bevel gear 48 is ixedly mounted on the rear end of the shaft 46 and this gear is meshably engageable with the bevel gear 49 which is iixedlyv mounted on the upper end of the vertically disposed driven shaft 50. Any suitable meshable pair of miter or worm gears could be used in place of the bevel gears 48 and 49. The vertical shaft 50 passes through the lower wall of the gear housing and through the upper wall of the housing portion 44 and is rotatably mounted in these walls by any suitable means, as by the sleeve bearing 51. The gear housing 45 is open on the upper side thereof and this opening is adapted to be enclosed by means of the cover plate 52 which is secured in place by the bolts S3. The cover portion 44 of the housing 31 is xedly mounted on the body portion 41 byk means of the bolts 54.

Fixedly mounted on the shaft 50, immediately below the sleeve bearing 51, is a bevel gear 55. The lower end of the shaft extends downwardly through the stationary arm 56 which is xed on the inner side of the housing cover portion 44. The bevel gear 57 is tixedly mounted on the lower end of the shaft 50 below the arm 56 and it meshably engages with the idler gear 53 which is rotatably mounted on the hub or boss 59 on the housing cover portion 44. The idler gear 5S meshably engages the bevel gear 60 which is a gear similar to the gear 57 and which is xedly mounted on the upper end of the vertically disposed shaft 61. The shaft 61 passesdownwardly through the fixed arm 62 and the lower wall of the housing cover portion 44 and is suitably journalled therein. Fixedly mounted on the shaft 6i between the arm 62 and the lower wall of the housing. portion 44 is the bevel gear 55a which is similar to the gear 55. Fixedly mounted on the lower end of the shaft 61 is a drive worm gear 63 which is meshably engaged with the driven worm gear 64 which is xedly mounted onV the shaft 65. As shown in Fig. 3, one end of the shaft `65 is rotatably mounted in the arm 66 which depends yfrom the housing cover portion 44 and which is. fixedly secured thereto by any suitable means, as by the bolt 67. The other end of the shaft 65 is fixed to one end of a splined sleeve member 68 and the other Vend of the splined sleeve member 68 slidably receives one. end of a shaft 69, which end is splincd.

As shown in Figs. l and 3,. the outer end of the shaft 69 is suitably rotatably journalled in the bracket 70 and has -xedly mounted on its outer end the drive bevel gear 71 which meshes with and drives the driven bevel gear 72 which is xedly mounted on the upper end of the shaft 73. The shaft 73 is rotatably mounted in the outwardly extended upper arm 74 of the bracket 75. The bracket 75 is lixedly mounted on the outer end of the slide 30 by any suitable means, as by the' bolts 76. The bracket is adjustably mounted on the. bracket 75 by means of the arcuate slot 76 and the loca bolt 7'?, so as to permit swiveling of the bracket 7d on the bracket when lthe housing 3l is adjusted.

l The bracket 75v is provided with Vthe lower outwardly extended arm 78 in which is suitably journalled the lower end of the shaft 73. YAs shown in Figs. l and 16, an elliptically shaped cam 79 is disposed between the arms' 74 and 78 and is xedly mounted on the shaft 73 by means of the lock key 80. Thecam 79 is adapted to rollably engage the cam roller 81 which is rotatably mounted on the shaft 82 on the bracket 83. The bracket 83 is xedly mounted on the slide 84 which is slidably mounted on ther guide 29 of the slide 12. The slide 84 is adjustable by reans of the screw rod v85, the inner end of which is threadably connected to the slide 84 in the usual manner and the outer end of which is rotatably mounted in the bracket 86 which is iixedly mounted on the outer end of the slide 12. The screw rod 85 is operable by means of the handwheel 87 which is fixed on the outer end of the rodv 85. It will be seen that the coil spring 38 normally urges the slide 30 outwardly so as to maintain the cam 79 in continuous engagement with the cam roller 81, and, that when the cam 79 is turned by the shaft 73, the slide 30 will be moved inn wardly toward the arm 36 a distance equal to the eccentric throw distance of the cam 79, as indicated by the numeral S8, and then moved outwardly toward the bracket 83 the same distance.

As shown in Figs. 1, 2 and 3, the numeral 89 generally indicates a rotatable spider -arm type rotary xture which includes the hub 90 which is adapted to rotate in the vertical plane. Fixedly secured to the hub 90, by any suitable means, is the journal 91 which is horizontally rotatably mounted in the longitudinal aperture 92 in the body portion 41 of the housing 31. The journal 91 is adapted to be rotatably carried in the tapered roller bearings 93 and is retained in place in the housing portion 41 by means of the annular retaining ring 94 which is threadably mounted on the rear end of the journal 91 and is secured in .place by the lock bolts 95. Fixedly mounted on the rear end of the journal 91 is a beveled ring gear 96 which is aiixed thereto by means of the screws 97 and the boss 98 on the rear end of the journal 91. The ring gear 96 meshes with and is driven by the two bevel gears S5 and 55a which are tixedly mounted on the drive shafts 50 and 61, respectively.

As shown in Figs. 1, 2 and 3, the rotary ixture 89 is provided with a plurality of xedly mounted spider arms 99 which are evenly arranged around the circumference of the hub 90 and which extend vertically and outwardly laterally from the hub 90 in the direction opposite to the journal 91. Fixedly mounted on the outer end of each of the spider arms 99 is a drill hold ing and clamping xture indicated generally by the numeral 100. As best seen in Fig. l, 4, 5 and 8, the drill fixtures 100 each include a body 101 which is xedly mounted on the outer end of a spider arm by any suitable means, as by welding. Each of the bodies 101 is provided with a transverse groove 2 adjacent the front end thereof in which is fixedly mounted a V-block 103, the ends of which extend beyond the sides of the body 101. ,The V-block 103 is adapted to support a drill which is to be ground, as 104, and is ixedly secured in the groove 102 by any suitable means, as by the bolts 105. The drill 104 is releasably clamped in the V-block 103 by means of the clamp 106 which is provided with the two drill engaging arms 107 on the front end thereof. 'Ihe clamp 106 is provided on the rear end thereof with an enlarged portion 108 through which is formed a transverse aperture 109 in which is `rotatably mounted the pivot pin 110.

As best seen in Figs. 5, 6 and 7, the pivot pin 110 is provided on each end thereof with an eccentrically mounted square, outwardly extended lportion 111. The square portions 111 are adapted to be mounted between a pair of integrally formed upwardly extended portionsr or shoulders, as 112 and 113, on each side of the body 101 adjacent the rear end thereof. Extending outwardly from each of the vsquare portions 111 is a centrally disposed round shaft 114 around which is mounted the upper end of a clip spring as 115. The lower ends of the clip springs 115 are mounted around the integral pins 116 on each side of the body 101. The clip springs 115 also each abut one of the shoulders 113 -which extend down the sides of the body 101. The clamp 106 is provided on the rear end thereof with a downwardly extended tail portion 117 through which is threadably mounte the body 101. The clamp 106 is adapted to pivot on the pin 110 and the screw 118 functions to limit the upward movement of the clamp 106. The eccentric mounting of the square portions 111 permits the pin 110 to be rotatably adjusted to various positions to permit the clamp 106 to be raised to a higher position when drills of larger diameter are to be held in the drill lixture for grinding.

The drill clamping fixtures 100 each include a clamping stud 119 which passes through the aperture 120 in the clamp plate 106 and through the aperture 121 in the fixture body 101. The stud 119 is provided on the upper end thereof with an enlarged head portion 122 which is adaptedto abut the top face of the clamp plate 106. Mounted around the stud 119 and between the clamp plate 106 and the fixture body 101 is a coil spring 123 which tends to bias the clamp plate 106 upwardly around the pin 110 to permit the loading and unloading of a drill 104 from the drill fixture 100. The stud 119 is providy ed with an annular washer 124 on its lower end at a point below the lixture body 101. A second coil spring 125 is mounted around the ystud 119 with the lower end thereof abutting the washer 124 and with the upper end thereof seated in the recess 126 in the lower face of the xture body 101. Spring 125 isa stronger or heavier tension spring than spring 123, and, accordingly, the clamp plate 106 is normally urged downwardly into clamping engagement with the drill 104 in the V-block 103.

The clamping force exerted by the heavy tension spring 125 is strong enough to hold the drills in place in the V-blocks 103 during the indexing and positioning actions described hereinafter, however, a cam lock means, generally indicated by the numeral 127, is provided for locked a screw 118, the end of which abuts the rear endof ing the clamp stud l119 in place during thegrinding action to provide additional holding force which is necessary when the drills are being ground.

As best seen in Figs. 1, 2, 4 and 8, the cam lock means 127 includes an arm 128, the lower end of which is bifurcated and pivotally connected by the pin 129 to the clamp stud 119 below the washer 124. The bifurcated lower end of the arm 128 is rounded olc and extends outwardly as at 130 to form a cam nose which contacts the washer 124 when the arm 128 is pivoted to the locked position shown in dotted lines in Fig. 4. The unlocked position of arm 1'28 is shown in Fig. 4 in the solid linesQ The upper end of the arm 128 is pivotally connectedby means of the pivot pin 131 to the outer end of a piston rod 132. The other end of the piston rod 132 is slidably mounted in the outer end of a suitable air cylinder 133 and is xedly connected to the piston 134. The air cylinder 133 is pivotally mounted at the inner end thereof on the spider arm 99 by means of the integral arm 135 which is pivoted on the pin 136 on the spider arm 99. Y

Air under pressure is supplied to the opposite ends of the air cylinder 133 by means of the tubes or

conduits

137 and 138 which are connected to the ow reversing valve 139. The Valve 139 is operated by the push button 140 which is in turn actuated by the bar 141 in one direction and which is spring actuated in the other direction in the usual manner as more fully described hereinafter. The bar 141 is xedly mounted on the arms 142 which are ixedly mounted on the Vertical supporting member 143 by any suitable means, as by the bolts 144. The supporting member is provided at the lower end thereof 'with the integral llanges 14S which are iixedly mounted on the housing portion 41 by means of the bolts 146.

Air under pressure is supplied to the valve 139 through the conduit 147 which is connected to the air cap 148.

The aircapl 148 has an outlet for each of the conduits Y 147 for all of the spider arms 99 and theseoutlets are connected to a passage 149 through the hub 90 which passage communicates withthe air chamber 150 inside of the journal 91. The air chamber 150 is supplied with air under pressure through the conduit 1 51, the-inner theA journal 91Y by mltIILSof the

bolts

15,31. The conduit' 151 extends through thering gear 96' and` is rotatably mounted in the boss 59 and outer'wall of the housing portion 44. The outer end' ofthe conduit' 151 is rotatably mounted in a swivelv 154" andlis connected to the stationary conduit S by means ofthe usual swivel con'- nection means 156. The conduit 15S. is adapted to b'e connected toY a suitable air compressor.

As best seen inFigs. 1, 2 and 3', the' vertical' supporting member 143 is provided on its upper end thereof with an integral forwardly extended horizontal arm157 which is disposed over the rotary iixture 89 on' the vertical plane through the rotary axis of. said fixture. A gravity feed drill hopper 1'58 is lixedly mounted o n the' horizontal arm 157 by means of the support members 159. The hopper 158 is disposed in vertical alignment overrthe path of travel of' the drill'holding' fixtures 100' and'- is adapted to' feed the drills 104 to be ground into the drill`iixtures.100`

as they pass' underneath. The drill hopper' 1.58 is pro'- vided onthe lower end thereof with a' narrowed neck portion 160 which is adapted to align the drills' 10'4"for'singu lar downward movement of the drills to' the drill holding' fixtures 100. The hopper neck portionj1'60 is' provided at its lower end with an inwardly extended finger, as 161, on each side thereof, andthese lingers function to support the lowermost drill 104 in the

hopperA

15,8 in a position whereby it may be' knocked out by the front end" of the arms 107 onthe clamp plate 106 'and' into the V-bloclt 103'.v The hopper neck portion 160 is open at Vthe lower end thereof, fromthe point indicated by the' numeral'162 downwardly to permitthe lowermost drill 104; to be removed froml the hopper 158.

As shown in Figs. 2 and 3, al vertically disposed-"sup-V port shaft 163 is iixedly mounted on the, outerend of the support arm 157 by any suitable means, as` by'welding. A collar 164 is-slidably mofunted'on the lower endof the shaft 16,3l and is adapted to be secured in aY desired adjusted positionby means of the bolt 165; -Thecollar 164 carries anintegral outwardly extending arm 166 which extends toward the rotary drill carrying fixture 8'9". The arm 166 is provided on its outer end:` with an integral support arm 167 having a downwardly tapered portion 168 disposed under and in alignmentwith the travel path of the drill iixtures 100 and just ahead of the-drill hopper position.

As best seen in- Fig. 3, the support. arm portion 168is adapted' to adjustably carry the curved riser bar 169 on `which' thev lower ends 170 of theV clamp studs' 1-19 are adapted'toride and be' raised asthey passthereover. As the cla-mp studs 119-are=lifted by the riser bar-169 the tension of the heavy clamping springs 125 is overcome and the lighter springs 123 'function-toepivot? the clamp plate 106 upwardly to the position shown in Fig. 8, whereby the drill iixture 100 is in a condition for the unloadingy and loading of a drill 104; The riser bar 169 isv adjustably mounted on the arm portion 168 by Vmeans of the Vadjusting screws 171, which are threadably mounted in the arm portion 168 with the upper ends thereof being rotatably secured in the lower side of the riser bar 169 by any suitable means.

As best seen in Figs. l, 17 and 18, a drill ejector means, generally indicated by the numeralV 172, is disposed along the path of travel of the drill fixtures 100'. The ejector means comprises a cylinder 173-which is iix edly mounted by any suitable means onthe arm 174. The lower end ofthe arm 174 is pivotally mounted, as by means of the pin 17S, on the arm 1'76which is pivotally mounted-on-theprojection- 177 onthe housing portion 41 byv means of the pin 178. Fixedly mounted on the forward end of the cylinder 173 is the stub arm 179 which is adapted to extendintothe p'atl'r of travel of th'e drill lixtxures 100 and to beY engaged by the 'outwardly extending VA-bloclrs 103 of the drill fixtures, soas to carry' the ejection` cylinder 17% a'short` distance' along with the drill slidably mounted' in the cylinder 173 in the' usual manner and is iixe'dly' connected'Y to the piston 181. The piston 181 is adaptedto bev biased inwardly to a non-operative position by means ofthe spring 182 and' to be biased outwardly to movethe ejection rod'180'into an operative position by means of a conventional solenoid 183'. An arm 184 is ixedly mounted on thetop ofthe housing portion 41 and has' fixedly mounted on its outer end the substantiall'y horizontally disposed support' bar 18S' which is providedwitlr axstop 186 at the' front end thereof. The arm 174 is provided with a projection or linger 187 which abuts the stop 186 when the ejection meansv is not functioning. A spring 188 isconnected at one end thereof to the pin- 189` on the arm 17-4, and at the other end thereof to the pin 1`90=on the housing portion 41. When the ejector meansk is carriedalong by a drill fixture 100,

the arms 174 and; 176 pivot on the pinv 17 8 and the linger' means 172 therealong will, bev ejected bythe ejection rod' 180 into a suitable discharge chute, as 197' 18').

Continued movement of the ejection means 172` causes the linger 187011 the arm174 to ride up the tapered cam' rise surface 198, therebycausing' the arm 174 tou-tilt` backwardly around the pin-175; whereby the' stub arm 179' is disengagedA from the V-block 103i of thev drilll'lixture' which carriedl the ejection means 172' allong with' it duringv the ejection process; The spring; SS'th'en' func'- tions to-return-the ejection means 172 back to' its' initial. position with the nger 187 against the stop 186. The spring 182 has inthe meantime returned the ejection rod to the inoperative positiom As best seenI in Figs. l and 43 an air cylinder' 19'9 is provided for positioning the drills 104 lengthwise inthe V-blocks 103 of the drill lixtures 100 after the` drills 104' xedly mounted on the arm 205 which is in turnixe'dly connectedv to the air' cylinder 199. The' aircyli`nder 199 1s provided v'vithl` the usuall air inlet lines 206` and" 207 and they in. turn ares' connected to. a solenoid type conventionalow control valve ZllSwhich' is connected t'o'- a suitable source. of pressured' air, by' means ofthe line 209' and: to the atmospherebytherline 210. The dow-control valve 208 sadaptedl tobe actuated by the-mieroaswiteh- 211'. whichis positionedV atl the exit endof thefriser'bar 169', whereby said switch 211V isactuated by means' of the clamp stud` lower end' 170 when` it' contactsA the switch' 211 after the loading. of' a drilll 1104' in a dir-ill xturelili- The micro-switch 211 is interconnected byfth'eline'sI 2111-2.Y to theA valve 2081 and'. to a suitable source'- of electrical energylas 2.13. Y

AsfshoW-ninf Figs; li, andQthrough'lS', a' drillL locator means is provided which is' generally indicated by the numeral l214. The' drill* locator means' 21:4` includes thev 9 cylindrical sleeve 215 which is mounted on the shaft 163 above the collar 164. The shaft 163 is threaded immediately above the collar 164 and threadably mounted thereon is the nut 216, at a point below the sleeve 215. The nut 216 is fixed in place by means of the set screw 217. The sleeve 215 'may be secured in an adjusted position by means of the set screw 218. The sleeve215 may be adiusted upwardly and downwardly on the shaft 163 by means of the nut 216 upon which it seats or rests. Fixedly mounted on the sleeve 215 is the track 219 which is circular in part and which is straight along the side 226i, and parallel along this side 220 to the path of travel of the drill fixtures 100. The upper surface of the track 219 is flat except on the straight part 220 which is curved on its upper surface similarly and in accordance with the path of travel of the drill fixtures 100. A carrier having the three arms 221 is rotatably mounted on the shaft 163 and it rests on the upper end of the sleeve 215, and, each of the arms 221 thereof, is provided with a slot 222 in which is slidably carried a slide as 223. Each of the slides 223 is provided with a vertical aperture 224 (Figs. 14 and l5) in which is slidably mounted the pin 225.

The lower end of the pin 225 extends down into an enlarged aperture 226 in a slide block 227 and is swivelly secured to the block 227, as by the pin 223. A spring 229 (Figs. 14 and 15) is mounted around the pin 225 and is interposed between the slide 223 and the block 227. The blocks 227 (Figs. 14 and 15) slide on the track 219 and the springs 229 normally bias the blocks 227 downwardly into a sliding engagement with the track 219.

Each of the blocks 227 is provided with a lip 230 (Figs. 14 and 15) which engages the outer vertical face of the track 219. The blocks 227 are normally held in position with each lip 230 abutting theouter face of the track 219 by means of springs as 231, the inner ends of which are fastened by means of the pins 232 to the arms 221 and the outer ends of which are fastened by means of the pins 233 to the slides 223. The carrier supporting the arms 221 is journalled on the reduced neck 234 of an adjusting nut 235 which is threadably mounted on the shaft 162 and which is adapted to be locked in place by means of the set screw 236.

The slide blocks 227 are provided with an axial bore 237 in the front wall thereof which communicates with the larger bore 238 which extends the rest of the way therethrough. Rotatably mounted in the bore 237 is a spindle or shaft 239, the rear end of which is rotatably supported by the bushing 240. The rear end of the spindle 239 is splined as at 241. The gear 242 is slidably mounted on the splined end 241 of the spindle 239 and is retained against endwise movement by means of the retaining bracket 243 which is fixed to the block 227, by means of the cap screw 244.

As shown in Fig. 1l, the bracket 243 is provided with an arcuate clearance opening 245 through which the splined shaft end 241 extends. As shown in Fig. 11, a stop 246 is provided on the back face of the block 227 against which the stud 247 on the gear 242 is adapted to abut. The coil spring 248 is mounted around the spindle or shaft 239 in the bore 238 and normally maintains. the shaft 239 in a position whereby the stud 247 abuts the stop 246. The front end of the spring 248 is iixedly mounted in the block 227, asiat 249, and the rear end of the spring 24S is iixedly mounted in the spindle 239, as at 250.

As shown in Figs. l0, l2 and 13, the front end of the spindle `239 is provided with an axial recess 251 in which is mounted the shaft 252 of a drill contact member having the enlarged head 253. The shaft 252 is fixed in the recess 251 by means of the set screw 254.. The back face 255 of the enlarged contact head 253 is adapted to abut the front end of the spindle y239. The enlarged head 253 s provided with a tapered recess 256 substantially similar to the shape of the lend of the drill 104 which is to be pointed, but being formed at an angle slightly less than the angle of the point of the drill. A pair of inserts, as

1:0 257, are mounted in the tapered recess 256 in an offset position so as to contact the offset lips of a drill 104 as shown in Fig. 20. The inserts 257 are fixedly mounted inv the. enlarged head 253 by any suitable means and they protrude outwardly a slight amount, as about 1/16 of an inch. The inserts 257 must protrude outwardly a distance suiicient enough to catch the lips of a drill 104 for turning it and locating it in the drill fixture y100. Fixedly mounted on the leading side ofthe block 227 is a horizontal outwardly extended arm 258 which is secured thereto by means of the screws 259. As shown in Fig. 11, the underside of the block 227 which contacts the track 219 is curved as at 260 similarly to the curved upper surface of the straight portion 220 of the track 219.

As shown in Figs. 2, 9, l1 and 12, the spindle 239 is provided with an integral pin-shaped cam follower 261 on the rear end thereof. The cam follower 261 is'adapted to engage the tapered face of the wedge-shaped cam 262 which is iixedly mounted on the track support member, by means of the bolts 263, in a position inwardly of the straight portion 220 of the track. A gear rack 264 is disposed on the track support member between the cam 262 and the straight portion 220 of the track and this rack is parallel to said straight track portion. The gear 242 is adapted to engage the rack 264 when the block 227 is moved over the curved upper surface section of the track, by means of a drill fixture `10() engaging the arm 25S and moving the block 227 along the curved upper surface of the straight portion 220 of the track 219.

The size of the circular track 219 is proportionate Vto the size of the circular path traveled by the rotary fixture 89 and to the number of stations or drill fixtures 100 carried on the rotary fixture 89, so that starting with a block 227 at the point y, shown in Fig. 9, the extended V- block 103 of a drill fixture 100 will engage the arm 258 of said block and will move the block along the curved upper surface of the straight portion 220 of the track 219. During such travel, the gear 242 engages the rack 264 and the cam follower 261 engages the cam 262. As the block 227 travels along the upwardly curved surface of the track portion 220, the spindle 239 will be cammed outwardly and the enlarged drill locator head 253 will engage the end of the drill 104 in the drill fixture 10i! which is moving the block 227. Simultaneously, the spindle 239 will beV rotated clockwise, as viewed in Fig. 9, by means of the gear 242 rolling on the rack 264 and the inserts 257 will engage the lips on the drill point. When the block 227 has been moved a distance suliicient to permit the cam follower 261 to move off of the cam 262, the spindle 239 will be positioned with the inserts 257 in a vertical plane, as shown in Fig. 20, and the drill 104 will be properly positioned for grinding. The inserts 257 willk always end up in a vertical position at this drop-off point gear 242 engages the rack 264 so that the drill locator head 253 on the spindle 239 is allowed to engage the point of a drill 104 before the gear 242 starts to turn on the rack 264.v It will be understood that the rack 264 is curved similarly to the upper curved surface of the straight portion 220 of the track 219.

As shown in Figs. l, 2 and 3, there are provided two similar grinding wheels, indicated by the

numerals

265 and 266, which are set parallel to the base 10 on which the rotary fixture housing 31 is mounted. These grinding wheels are disposed to rotate on an axis which is disposed at an angle equal to the desired angle torbe ground on the drills 104. v As shown in Fig. 21, the angle of the illustrative drilly is 59 and, (accordingly, the grinding

wheels

265 and 266 would be set ,with their longitudinal axis atan angle 'f 59 to the axis of rotation of the rotaryV assmss l 11 Y- drill fixture 89, and this setting angle is indicated in Fig. l by the letter x. As illustrated' inFig. 22, the right grinding wheel 265, as viewedjin Fig. 1, is adapted to grind the one relief surface 267 on a drill pointjfrom the heel 268 to the lip 269 as the rotary xture 89 is moved outwardly, that is, as the slide 30 moves, outwardly on the slide 12 away from the'grinding wheelsvor to the rightv The heel 268 and lip 269 portions scribed. As shown in Fig. 2, the grinding wheel 266 is mounted on the shaft 273 against theV flange 274 on said shaft. shaft 273 by any suitable means, as by the lock key 275. The grinding wheel 266 is fixed against end-wise movementon the shaft 273 by means-ofthe retaining plate 276v and the nut 277. The shaft 273 is rotatably mounted in the slide block 278 whichis slidably mounted on the guide 279 on the base 280. Fixedly mounted'on the base 280, bymeans of therbolts 281, is an upwardlyextended plate 282 through which is rotatably mounted a screw rod 283; Fixedly mounted on the end of the screw rod 283 is a handwheel 284Yfor actuating the rod-283. The inner'end of the screw rod 283 is threadably mounted in the slide block 278, in the usual manner. The outer end of the sha-ft=273V carries the pulley 285 which is drivenby the, belts 286which pass around the pulley 287.v The pulley 287 is fxedly mounted on the end ofthe'shaft 288 of the motor-289 which is fixedly mounted on the top of the slide 278, as by means of the bolts 290.

' In operation, with the grinding wheels 265 and- 266 set at the desired angle relative-to the rotaryfixture 89,and with the wheels dressed toapproximately the-same diameter, by any suitable means, the drill hopper 158 would bel loaded with drills 104 with the points thereof facing toward the locating mechanism 214. YThe drills 104, Vat this stage, would bealready rough turned-with the points roughly; formed thereon, and with only the finish pointingV grinding operation` remaining to be performed; The

motors

19, 40 and 289 for driving the rotary fixture 89

andthe grinding wheels

265 and 266 would then-be actuated `and the rotary fixture 89 and the grinding

wheels

265 and 266 would then be actuated and the rotary fixture 89 would berotated in aclockwise direction, vas viewed in Fig. 3.

Assuming a start withanempty drill fixture, as the drill clamping iixture100 leaves the grinding wheel 266the'air control button 140 will engage the rail 141 andbe operated to let air enter conduit 138 to move the piston 134 from the position shown in Fig. l to theposiy the front portions 107 of theclamp plate 106.into engagement withthe lowermostldrill'104 in the hopper 158.and the portions V107 will knock said drill from the lips Y161 ofthe hoppen into theV-.hlock 10S-of Vsaid fixture. v Con tinuedmovement of the drilLfxturer 100 will cause'the j clampingstud 19 to ride down-the downwardly tapered exit end 169i: V(Fig. 3) ofthe riser rail 169. "Ihelieavy The grinding wheel 266 may be locked on the spring 125 in the drillrxture will then move the clamp plate..1 6, into` a clamping engagement` with the drill 104. The clamping stud 119 then rides off of the tapered rail end 169a and engages the micro-switch 211 whichactuates the air cylinder 203. The air cylinder 203 then actuates the positioning plate 201 outwardly into engagement with the point of the drill 104 so as to position said drill to the proper length wise position in the V-block 103.

. Continued movement of the drill fixture 100 causes the Y exit end of the tapered cam 262.

extended V-block 103 to contact the arm 258 on one of the blocks 227 which is disposed at the position y, shown in Fig. 9. As the drill fixture prooceds in its movement, therspindle 239in the block 227 will be moved outwardly and will engage the pointed end ofthe drill in the manner described hereinbefore. Continued mover ment of the drill fixture 100 moves the block 227 alongl the curved upper surface of the straight portion 220 of the track219 and the drill point will be properly positioned for grinding during such movement. The drill 104 will be properly positioned for grinding, with the lips of the drill in a Vertical plane, at the point in the travel of theY block 227 along the straight portion 220 of the track 219 at which the cam follower 261 drops off of the As the drill fixture 100 continues tomove, the arm 258 on the block 227 Will be disengaged from the drill xture 100 and such movement of the-block 227 will have moved the locator arms 221 so as to move the succeeding block 227 to the point marked y in Fig. 9, whereby said succeeding block 227 willrbe picked up and carried through a locating or indexing operation by the next drill fixture 100. As the drill fixture 100 continues in its movement, the air push button 140 will ride off of the rail 141 and air under pressure will flow through the conduit 1 37 to force the piston 134 downwardly and the arm 128 will be pivoted to bring the rounded nose 130 of the cam locking means upwardly against the washer 124 to the dotted position shown in Fig. 4, and the drill 104 will be securely locked in position for the grinding operation.

The rotary fixture 89 continues its rotation and brings the drill- 104 adjacent the right grinding wheel 265 at a point in the rotaryfmotion of the cam 79 when it is ready to permit movement of the slide 30 outwardly on the slide 12 or transversely away from the grinding

wheels

265 and 266 under the action of spring 38 toward the bracket 83 as viewed in Fig. 1. As Viewed in Fig. 22, the one side or relief surface 267 of the drill point is then ground from the heel 268 of the relief surface 267 to the lip 269 of said surface, as the rotary fixture 89 is transversely backed away from the grinding

wheels

265 and 266.

VThe heel 268 of the relief surface 267 on the drill point engages the counter-clockwise rotating grinding wheel 265 at the point marked 291, as shown in Fig. 26. The drill 104 is then moved backwardly, longitudinally and circumferentially relative to the wheel 265and grinding on the relief surface 267 takes place until the tangential point 292 is reached, at which point the lip 269 is ground and thev rotary fixture 89 carries the drill 104 away from the wheel 26S and on to the wheel 266. Continued rotation of therotary fixture 89 brings the other side or relief'surface 270 of the drill point into grinding engagement with'the Wheel 266, at the tangential point 293 on the wheelv26r6. The lip 271 of the relief surface 270 engages the Wheel 266 at the tangential point 293 and as the rotary fixture 89 moves toward the grinding wheel 266, the relief surface 270 is ground from the lip 271 to the heel 272. The grinding action is complete when theV heel 272 breaks engagementv with the wheel 266 at the point'-294'. if Fffhe-dri ll point follows a` helical path Vacross the upper diameter of the grinding wheels` 265 and 266 during the grinding action, as shown in Figs; 26 and 27.

'The aforegoingi grinding 'action is illustrative of thei grinding action on one drill. However, during one complete rotation of the rotary fixture 89, fifteen drills will be ground, since the fixture 89 is provided with fifteen stations or drill holding fixtures 100. During one complete revolution of the rotary fixture 89, the cam 79 makes fteen complete revolutions. The rotary fixture 89 may be provided with more or less stations than shown, but the total number of stations must always be an odd number so that when the fixture 89 is rotatably moving one drill down and away from the grinding wheel 265 after grinding a relief surface 267 it is ready to next move a drill on a fixture 89 upwardly into engagement with the wheel 266 on the forward stroke of the rotary fixture 89 toward the grinding wheels, that is, toward the arm 36, due to the action of cam 79 to grind a relief surface 270. The relief surfaces 267 and 270 are not ground simultaneously but alternately since the total number of fixtures is always an odd number.

After the drill 104 leaves the grinding wheel 266, the rotary xture 89 rotatably moves the drill fixture 100 in the clockwise direction as viewed in Fig. 3 and the air button 140 will be engaged by the rail 141 as described hereinbcfore. The clamp stud 119 will engage the riser bar 169 as described hereinbefore and the clamp plate 106 will unclamp the drill 104 as previously explained. The V-block 103 engages the arm 179 on the ejection means 172 and the ejection means then operates as described hereinbcfore to discharge the drill 104 into the chute 197 or any other suitable receiving receptacle. The drill fixture 100 is then carried again to the hopper 158 for reloading and the cycle is repeated.

The particular machine described would preferably use grinding wheels which are 18" long and 18" in diameter and the rotary xture 89 would have a 24 inch swing, that is, the diameter of the rotary path of the drills 104 would be approximately 48 inches. The rotary locator track 219 would have a diameterof approximately 14 inches so that the blocks 227 would be picked up by the drill fixtures 100 evenly and smoothly in gearlike action. The particular machine shown is suitable to grind drills up to one-half inch in diameter. The eccentric movement of the cam '79 for the machine shown would be about 2 inches. That is, the distance 88 through which the rotary fixture S9 is moved by the cam 79 causes the drills 104 to be moved longitudinally forwardly and backwardly relative to the grinding

wheels

265 and 266. about 2 inches. The aforementioned figures would, however, vary depending on the size or diameter of the drill to be ground. Also, for different desired angles on the drill points, the settings of the grinding

wheels

265 and 266 would have to be adjusted accordingly, relative to the rotary fixture S9 and the slides 12 and 30.

lf the drill 104 is required to have a different clearance angle, the machine could be provided with grinding wheels mounted to be adjustable in various planes, as shown by the grinding wheels in Figs. 24 and 25. Numeral 295 indicates a grinding wheel mounted on the shaft 296'by means of the end plate 297 and the nut 298. The shaft 296 is suitably rotatably mounted in the end wall 299 of the slide 300. A motor 301 is fixedly mounted on top of the slide 300 and drives the pulley 302 which drives the belts 303 and the pulley 304 which is mounted on the outer end of the shaft 296. The slide 300 is slidably mounted on the dovetail guide 305 on the slide 306, and the screw rod 307 is adapted to move the slide 300 on the guide 305 on the slide 306. The inner end of the rod 307 is threadably mounted in the slide 306 in the usual manner and the other end is rotatably mounted in the block 308 which depends from the slide 300. The outer end of the screw rod 307 is connected by the ycoupling 309 to the gear reducer 310 which is fixedly mounted on the bracket 311 which is xed on the block 308 on the slide 300. The `gear reducer 310 is connected to a constant speed motor 312 by means of the coupling 313. The motor Y'14 312 may thus provide a continuous feeding motion to the grinding wheel 295 and this motor may be reversed by means similar to that used on motor 19 of Fig. 2; The slide 306 is pivotally mounted on the pin 314 which is fixed in the slide 315 and the slide 306 is retained in an adjusted position on the pin 314 by the set screw 316. The slide 315 is slidably mounted on the guide 317 on the block 318.- The slide 315 is movable on the block 318 by means of the usual screw rod 319 which is rotatably mounted in the arm 320 which is fixed on the block 31S. The screw rod 319 is actuated by means of the handwheel 321. The block 318 is pivotally mounted on the pin 322 which is fixed in the base 323 and the block 318 is retained in an adjusted position by the set screw 324. It will be seen that the modified grinding wheel mounting structure of Figs. 24 and 25 provides a means for adjusting the position of the grinding wheels relative to the rotary fixture 89 for various drill angles.

The invention is described for use in grinding right hand drills but left hand drills may be ground by reversing the action of cam 79 and grinding the drills on the lower diameter of the wheel. It will be understood that the path travelled across the grinding wheels by a drill point will be longer for increasingly larger sized drills, and vice versa. The rotary fixture base 10 and the grinding wheel bases 280 are preferably mounted on a common base plate 325.

While it will be apparent that the preferred embodiments of the invention herein disclosed are Well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What I claim is:

1. A machine for grinding points on drills comprising: a base having a longitudinal axis; a rotary drill carrying fixture movably mounted on said base and rotatable in a vertical plane about a horizontal axis disposed at an acute angle to the longitudinal axis of said base; means for moving said fixture on said base in a direction transversely to the longitudinal axis of said base; means for rotating said fixture; releaseable clamping means on said fixture for releasably holding a plurality of drills; a pair of laterally spaced apart rotatable grinding wheels, each having a longitudinal axis and being disposed with their longitudinal axes horizontal and parallel to the 1ongitudinal axis of said base; said kgrinding wheels being disposed adjacent the path of travel of the drill holding means on said fixture; and, means for moving said fixture forwardly and backwardly on said base in a direction parallel to the longitudinal axis of said base and the longitudinal axes of said grinding wheels and in timed relation to the rotation of said fixture, whereby, each of the drills carried by said fixture will be moved into grinding engagement with the periphery of one of said grinding wheels during the backward wovement of said fixture for grinding one side of the point on each of the drills, and, the drills will then be moved into grinding engagement with the periphery of the other of said grinding wheels during the forward movement of said fixture for grinding the other side of the point on each of thedr'ills.

2. A machine for grinding points on drills comprising: a base having a longitudinal axis; a rotary drill car'- rying fixture movablyrmounted on'said base and rotatable in a vertical plane about a horizontal axis disposed at an acute angle to the longitudinal axis of said base; means for moving said fixture on said base in a direction transversely to the longitudinal axis of said base; means for rotating said` fixture; releasable 'clamping means on said'fixture for releasably holding a plurality of drills; means for automatically operating said Yreleasable clamping means; a pair of laterally spaced Vapart rotatable grinding wheels, each having a longitudinal axis, and being disl posedrwith their longitudinal axeshorizontal and parallel to the longitudinal axis of said base; said grinding wheels being disposedi adjacent the path of travel of the drill holding means on said fixture; and, means for moving said fixture forwardly and backwardly on said base in a direction parallel to the longitudinal axis of said base andthe longitudinal axes of said grinding wheels and in timed relation to the rotation of said fixture, whereby, each of :the drills carried by said fixture will be moved into grinding engagement with the periphery of one of said grinding wheels during the backward movement of said fixture for grinding one side of the point on each of thedrills, and, the drills will then be moved into grinding engagement' with the periphery of the other of said grinding' wheels during the forward movement of said fixture for grinding'the other side of the point on each of the drills.

3. A machinev for grinding points on drills comprising: a base-having a longitudinal axis; a rotary drill carrying fixture movably mounted on said base and rotatable in a vertical plane about a horizontal axis disposed at an acute angle to the longitudinal axis of. said base; means for moving said fixture on said base in a direction ytransversely to the longitudinal axis of said base; means fory rotating said xture; releasable clamping means on said'fixture for releasably holding a plurality of drills; means for automatically operating said releasable clamping means; a pair of laterally spaced apart. rotatable grinding wheels, each having a longitudinal axis, and being disposed with their longitudinal axes horizontal and parallel to the longitudinal axis of said base; said grinding wheels being disposed adjacent the path of travel of the drill holding meansv on said fixture; means for moving said fixture forwardly and backwardly on said base in a direction parallel to the longitudinal axis of said base and the longitudinal axes of said grinding wheels and in timed relation to the rotationof` said fixture, whereby, each of the drills carried by said vfixture will be moved into grinding engagement with the periphery of one of said grinding wheels during the backward movement of said fixture for grinding one side of the point on each of the drills, and, the drills will then be moved into grinding engagement with the periphery of the other of said |grinding wheels during the forward movement of said fixture for grinding the other side of theV point on each of the drills; and a drill ejector means for removing the drillsfrom said clamping means after the points have been Yground on the drills.

4. A machine for grinding points on drills comprising: a base having a longitudinal axis; a rotary drill carrying fixture movably mounted on said base and rotatablel in a vertical plane about a horizontal axis .dis-

posed at an acute angle to the longitudinal axis of said,

base; means for moving said fixture on said base in a direction transversely to the longitudinal axis of said base; means Vforrotating said fixture; releasable clamping means on said fixture for releasably holding a plurality ofl drills; means for automatically operating said` releasable Yclamping means; a pair of laterally spaced apart rotatable'grinding wheels, each having a longitudinal 4axis,xand being disposed with their longitudinal axes horizontal and parallel to the longitudinal axis `of-said base; saidgrinding Wheels being disposed'adjacentgthe path1of travel of thel drill holding means onV said: fixture; vmeans for moving said fixture forwardly and backWardly-,on said base in a direction parallel to theY longitudinal axis of said base and the longitudinal axes of saidgrinding wheels and intimed relation to the rotation ofsaid fixture, whereby, each of the drills carried Y by said fixture willl be moved intogrinding engagement with the periphery-of one of said grindingwheels during thexba'ckwardv movement of said Vfixture for grinding one side of the point on each of the drills, and, the drills M ldwill thenV be moved intogrinding engagement with the periphery of the othenfof said grinding wheels during the forwardmovement-of saidA fixture for' grinding the other side of thefpoint'on each ofthe drills; a drill ejector means for removing the drills from said clamping means after the points'have been ground on the drills; and, means for automatici-illy loading drills into the drill clamping means after the nish ground drills have been ejected therefrom;

. 5. The grinding machine as set forth in claim 4, wherein: sai-d. machine includes a means for positioning the drills lengthwise in the clamping means.

6. The grinding machine as set forth in claim 5, wherein: said machine includes a drill locator means operable by said rotary drillcarrying fixture for locating the drills in said clamping means with the lips of the drills positioned to permit one of said grinding Vwheels to grind one of the faces on a drill point and the other of said grinding wheels to grind the oppositely disposed other face .on a drill point. Y Y

'1. 'The grinding machine as set forth in claim 6, wherein: saidmachine isprovidedwith means for moving said rotary drill'` carrying fixture longitudinally of said grinding wheels.

8. A machine for grinding points on drills comprising: a 'base plate; a base havingl a longitudinal axis fixedly mounted on said base plate; a longitudinally disposed guide on said base; a slide movably mounted on said guide on said lbase; means for automatically moving said slide on said guide on said base; a guide on said first named slide disposed at a right angle to the guide on said base; a secondk slide movably mounted on saidy last named guide; meansY for'moving said second slide backwardlyrand forwardly on said last named guide; a housing adjustably mountedon said second slide; a rotary drill carrying fixture rotatably mounted on said housing and rotatable in a' vertical plane about a horizontal axis disposed at an acute angle to the longitudinal axis of said base; means forrotating said rotary fixture; releasable clamping means on said rotary fixture for releasably holding a plurality of Idrills; a pair of laterally spaced apart-rotatable grinding wheels each having a longitudinal axis, and being disposed on said base plate with their longitudinal-axes horizontal and parallel to the longitudinalV axis-ofthe longitudinally disposed guide on said base; said grinding wheels being disposed adjacent the path of travel of the drill holding means on said rotary fixture;v and, means for automatically operating said releasable clamping means.

9. The grinding machine as set forth in claim 8, wherein: said machine is providedwith a drill ejector means for automatically removing the drills from said clamping means vastherotary fixture is rotated and after the points have been ground on the drills.

l0. The grinding machine as set forth in claim 9, wherein: v said machine is provided with means for automatically, loading drills into the drill clamping means after the finish grounddrills have been ejected therefrom and as .the rotary fixture is rotated.

1l. The grinding machine as set forth in claim l0, wherein: said machine is provided with a means for positioning thefdrills lengthwise in they clamping means as the rotaryr fixture is rotated.

12. The grinding machine as set forth in claim l1, wherein: said machinel is provided ".vith drill locator means operable by said rotary drill carrying fixture for locating-the drills ihn-.the clampingzmeans in a predeterminedrotary position-for grinding a first face on adrill point` on one of the grinding` wheels and a diametrically justably mounting the grinding wheels to permit the grindingiof various angles on the point of a drill.

14. The grinding machine as set forth in claim 12, References Cited in the le of this patent wherein: said means for moving said second slide includes 2,410,348 Johanson Oct. 29, 1946