US2268714A - Tool sharpening and gauging machine - Google Patents

Description

Jan. 6, 1942. J. F. McCARTHY, JR

I TOOL SHARPENING AND GAUGING MACHINE Filed March 31, 1939.

3 Sheets-Sheet l F-i-I "illlllll. J. 6 M n 1 a A... u H 1" 4 6 n a i l 2' w F a w a a m a m a a m a u 0 u m m m a 5 a a I" F o a a 2 1 6 a a z 3 h a n o i 5 JAMES F. MC CARTHY, JR.

Gttomeg Jan. 6, 1942.

J. F. M CARTHY, JR 2,268,714

TOOL SHARPENING AND GAUGING MACHINE I Filed march :51, 1939 3 Sheets-Sheet '2 lumentor C(ttomeg Jan. 6, 1942. J. F. McCARTHY, JR

TOOL SHARPENING AND GAUGING MACHINE Filed March 31, 1939 5 Sheets-Sheet 3 I l I WIH'HHFUI IH H lnni flul G A a m m 1 I I 'III lllll'lllllll I 3 m 9 8 u M 5 4 4 JAMES F. no GARTHY, JR.

Inventor dim-neg Patented Jan. 6, 1942 UNI-Ten stars-s Parem "or ies TOOL SHARPEN IN G AND GAUGING MACHINE James McCarthy, Jr.,, Wallace, Idaho Application March 31, 1939, Serial'No. 265,249

14- Claims.

My present'invention relates to improvements in tool sharpening and gauging machines for detachable bits of the type commonly used in rock drilling and mining.

In mining the drilling machine operator will take a quantity'of bits to. the heading where he is to work'and where he has been provided with a number of different lengths of drill rods. The bits are fitted-to the rods and used until they become dull. The cutting edges will be battered and distorted sothat they are of no further use for drilling purposes in their present condition. Economical mining requires that the maximum of use be obtained from such bits, and therefore resharpening of the dulled bits is highly desirable. To be effective, such resharpening must be accomplished simply and efiiciently due to the low initial cost of such bits. When the cutting edges of the bits have been resharpened, the gauge faces, of the bit must also be re-gauged to insure accurate workmanship in subsequent drilling. Due to the. extreme hardness of the steel used in the detachable bits, I have found that sharpening and gauging may best be done when the bit has been heated. to a high degree of temperature.

An important object of my invention istoprovide a precision bit sharpening and gaugingmachine, adjustable to accommodate various types and'sizes of-bits.

Another object of my machine is the provision of means whereby the bit to be sharpened may be handled while at a high heat.

A further object of the invention is the provision of a bit holder which will readily receive and securely hold the bit. while it is being presented to the facing tools.

Still another object of the invention resides in the features of the machine whereby it may be quickly and conveniently adjusted to sharpen and gauge difierent sized bits.

A still further object of the invention has been the provision of such a machine as has been described-that maybe produced, installed: and operatedatthe lowest possible cost, to permit the resh'arpener to compete favorably with the original producer.

Other objects and advantages of the invention will'be apparent during the course of the following description.

In the accompanying drawings, forming a part of this specification, and in which like numerals are, employed to designate like parts throughout the Same,

i holder of my machine with tor stand upon which the motor II I surface a pair of V-ways lE-I'S'.

Figure l is a side elevation of the millingmachine embodying my invention,

Figure 2 is a front elevation of my machine,

Figure 3 is an enlarged detail view of the bit 7 portions broken away for the convenience of illustration,

Figure 4 is a view of a portion of the bit holder of my invention illustrating the bit-clamping action therein, 7

Figures 5 and 6 are, respectively, side and end views of a typical detachablexbit to which my machine is adapted for sharpening and gauging, and a Figure 7 is a view in elevation of the bit holder arm, showing the manner in which a bit is fitted thereon. I I

- In the drawings, wherein for the purpose of illustration is shown thepreferred embodiment of my invention, the numeral III designates a mois securely mounted. Upon the shaft IZ of' the motor I mount the rotary sharpening miller I3.

A base plate I4 is provided and extends to one side of the stand I0, andhas'upon its upper A slidable motor carriage I6 is supported on "the plate I4' and is longitudinally slidable, guided upon the ways I5. A boss I7, at one edge of the plate I4, supports a carriage screw I8 secured tothe carriage I6 by means of the boss I9. outwardly from the carriage and parallel to the plate I4 and is provided with elongated slots 2 I2 I, and anchor bolts 2222 pass through the slots 2| and are threaded into the plate I4 for securely anchoring the carriage in an adjusted position.

The carriage IB- is substantially triangular in elevation and at its upper apex is provided with hinge ears 23- 23 which support a pivot pin 24. An adjustable motor mounting plate 25 is pivotally supported from the pin 24, and a gauge screw 26 in the opposite end of the plate 25 serves to adjust the angle of the plate with relationship to the rear sloping wall 21 of the carriage. A

motor 28 is mounted on the plate 25, and upon the motor shaft 29 is secured for rotation the gauging miller 30.

A carriage slide BI is supported from one face of the stand ID by meansIof the arm 32, and the bit holder carriage 33 is slidably engaged thereon, as may best be seen in Figures 1 and 3. Depending from each of the longitudinal edges of the carriage 33 are flanges 34 which engage the side edges and a portion of the under surface Of the member '3I and are provided with set A flange 20 extends screws 35 for securely locking the carriage in adjusted position.

Upon the upper surface of the carriage is mounted a pair of bearings 36 and 31. A shaft 38 is fitted in the bearings for rotation. A collar 39 is fixed to the shaft 38 between the bearings and carries an upstanding tubular arm 40. The flanged bushing 4| is fitted into the open end of the arm. A ball thrust bearing 42 in the lower depth of the arm 40 takes the thrust of the pin 43, upon which pin is formed a bit holding head 44. The pin 43 is grooved at 45, and a keeper screw 45 engages the groove to hold the pin within the arm 40 and also the bushing 4|.

A collar 45 is secured to an overhanging end of the shaft 38 and supports an arm 41 extending at right angles thereto. A dolly support bushing 48 is slidably mounted upon this arm and has an upper sloping cam surface 49. A cam 50 is also provided on the arm 41 and has a lower cam surface and the cam operating handle 52 extends outwardly from the bushing 58.

An expansion spring 53 encircles the arm 41 and is retained in place upon the upper surface of the bushing 50 by means of the spacer collar 54 and the nut 55 threadably engaged with the arm 41. Between the dolly bushing 48 and a fixed collar 56 I provide a return spring 51 which also encircles the arm 41.

A dolly supporting arm 58 extends from one side of the bushing 48 and carries the dolly head 59. By means of suitable bearings 68-458, a dolly mandrel 6! is mounted for rotation within the head 59; At the upper end of the mandrel I form a crank 62 for rotating the mandrel, which has at its lower end a dolly .63. The dolly 63 may be substantially round and tapered and has bit engaging points 64 and a centering point 65.

The carriage 33 at its rear end has an upstanding ear 66, and the slide 3| has an ear or boss 61. A carriage screw 68 is rotatably mounted in the ear 66 and threaded in the boss 61 and may be turned by means of the toggle-handle 69.

Referring now to Figures 5 and 6, wherein I have illustrated, in side and face views, a typical drill bit, it will be apparent that the bit consists of an interiorly threaded body portion having a lower skirt 1|, and four radial extending wings as 12, 13, 14 and 15. The upper impact faces of the wings are tapered to form a cutting edge 16. The outer face of the wing at the largest diameter is ground to form gauge faces 11.

The rotary sharpeningmiller I3 is circular and has sloping cutting faces 18 and 19 tapering outwardly from the center.

Referring to Figure 1, I have shown an upstanding bar 80 secured to the back of the collar 46 which protrudes sufficiently high so that the upper end is located directly behind the bushing 48, Lug 8| on the bushing 48 in certain positions abuts against the bar 80 and impedes further rotation of the bushing 48 on the arm 41, to align the dolly 63 with the bit to be gauged.

Method of operation Before starting the operation of sharpening and gauging bits, the dull bits are sorted for size and type and are heated in a suitable furnace to approximately 1600 degrees F. Certain types of bits require a taper on the gauge face of approximately 3 degrees. This taper varies with other types of bits as well as in accordance with varying conditions to be met. To adjust the gauging miller the operator will loosen the anchor screws 22 and unlock the carriage screw l8. By turning the carriage screw la the carriage I6 is slid forward or back to the desired location, whereupon it may be again securely locked against movement.

To vary the angle of the beveled gauging miller the gauge screw 26 is turned one way or the other to increase or decrease the angle between the adjustable motor mount 25 and the rear face 21 of the carriage, it being apparent that the mount 25 swings pivotally on the pin 24.

Because the depthof the bit, measured by the distance between the extreme edge of the skirt 1| and the cutting edges 16, varies with different bits, it is occasionally necessary to adjust the swinging bit holder so that the bit will be presented to the sharpening miller l3 in the proper manner. To accomplish this adjustment the carriage 33 is moved on the slide plate 3| after loosening the set screws 35 by turning the carriage screw 68 to either advance or withdraw the carriage as deemed advisable.

To sharpen a bit the operator removes it from a furnace with a pair of tongs and places it upon the head 44. It will be understood that the dolly collar is swung out of the way, as may be seen in the dotted line position indicated in Figure 2. The tubular arm 46, carrying the bit to be sharpened, is presented to the miller I3 with the tapered faces of the miller 18 and 19 cutting or dressing the tapered upper faces of the wings of the bit. The miller cutting faces in this operation are interposed between a face of each of the adjoining. angularly disposed wings of the bit. Whentheproper out has been taken the operator indexes the bit on the h'ead 44 to successively present the other faces of the bit for sharpening.

When the bit has been properly sharpened on the miller l3, the dolly and its mandrel and crank are swung from the dotted line position of Figure 2 to the solid line position shownin Figures 2 and 3, so that the lug 8| contacts the stop bar 89. The cam 50 is now turned from the position shown at Figure 3 to that in Figure '4 to depress the dolly bushing 48 on the arm 41 and cause the dolly to engage the cuttingfaces of the bit.

It is customary that bits of the type herein being treated will be provided with a central water hole, in which case the centering pin 65 will enter the water hole. Of course, for bits of the type that do not have a central water hole a centering pin will be omitted from the dolly.

By turning the mandrel 6| through the operation of the crank 62, the bit may be readily revolved on the tubular arm 40, the thrust being taken by the ball bearing 42.

The operator now swings the complete unit, comprising the shaft 41, the arm 40 and the crank 62, to the dotted line position of Figure l, and in this way presents the faces 11 of the bit to me beveled miller 30 for gauging. Suitable stops may be provided to support the weight of the bit holder unit, and it will of course be apparent that the stops may be made adjustable so that various positions will result.

To gauge the bit the operator merely cran'ks the mandrel and the dolly 63 so that successively the different faces 11 will be presented to the gauge miller 30. I

Upon the completion of the gauging operation the bit holder unit is returned to the upright position, the cam 58 is released, and the spring 51 will lift the dolly bushing 48, together with the dolly :63 out of engagement with the bit. By swinging the dolly and its bushing 48 on the arm the bit may readily be lifted 'ofi the pin '44 andreturned to the furnace for additional heating in preparation for tempering or for-am healing, or if the heat is 'still sufficiently high the bit-may be quenched at this time.

It is to be understood that the 'form of my invention, herewith'shown and described, is to be taken as a'preferre'd example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of my invention or the scope of the subjoined claims. --'What I claim .as new and desire to secure by Letters Patent is:

.1. In a drill bitsharpening'machine, the combination vof a base structure, arotary driven sharpening miller supported, thereon, a carriage slide supported from a base structure adjacent the sharpening miller, a slidable carriage operable with'said slide, a bit holder swingingly mounted upon the carriage in alignment with the sharpening miller, a rotary driven gauging miller supported from said base in the path of the swinging bit holder, a rotatably mounted head for engaging the cutting face of a bit upon said bit holder when the latter is swung to present such bit to said gauging miller, and means to 110- tate said head during the gauging operation.

2; In a drill bit sharpening machine, the comupon swinging movement of the bit holder-arm, a

bination of a base structure, a rotary driven I sharpening miller supported thereon, a slidable carriage supportedadjacent the sharpening miller, a bit holder swingingly mounted upon said carriage in alignment with the sharpening miller, a rotary driven gauging miller supported from said base in the path of the swinging bit holder, a rotatably mounted head for engaging the cutting face of a bit upon said bit holder when the latter is swung to present such bit to said gauging miller, and means to rotate said head during the gauging operation.

3. In a drill bit sharpening machine, the combination of a base structure, a rotary driven sharpening miller supported thereon, a bit holder swingingly mounted on said base structure and comprising a tubular arm and a rotatable pin having a head for the reception of a bit to be sharpened, a rotary driven gauging miller sup ported from said base in the path of the swinging bit holder, a rotatably mounted head for engaging the cutting face of a bit upon said bit holder when the latter is swung to present such bit to said gauging miller, and means to rotate said head during the gauging operation.

4. In a drill bit sharpening machine, the com bination of a base structure, a rotary driven sharpening miller supported thereon, a slidable carriage supported adjacent the sharpening miller and provided with hearing blocks, a shaft mounted in said bearing blocks, a bit holder comprising a collar on the shaft, a tubular arm extending laterally from said collar, and a bit receiving pin rotatable within said arm; a rotary driven gauging miller supported from said base in the path of the swinging bit holder, a rotatably mounted head for engaging the cutting face of a bit upon said bit holder when the latter is swung to present such bit to said gauging miller, and means to rotate said head during the gauging operation.

5. In a drill bit sharpening machine, the combination of a base structure, a rotary driven er arm swingingly :mounted on said base structure in alignment with the sharpening miller, a rotary driven gauging miller mounted on said base in the path of a swinging bit holder, a dolly arm parallel 'to the bit holder arm and movable a rotatably mounted head on said dolly arm-- for engaging the cutting face of a bit upon said bit holder when the latter is swung to present such bit to said gauging miller, and meansto .rotate said head duringthe gauging operation.

6. In a drill bit sharpening machine, the combination of a base structure, a rotary driven sharpening miller supported thereon, a bit "holder arm swingingly mounted on said base structure inalignment witha sharpening miller, a rotary driven gauging miller supported from said base in the path of the swinging bit holder, a

dolly arm mounted to swing parallel to'the bit holder arm, a bushing on said dolly arm, a rotatably mounted head on saidbushing for en gaging the cutting face of a bit upon said bit holder when the latter is swung to present such bit to said gauging -miller1and means to rotate said head during the gauging; operation.

7; In a drillbi't sharpening machine, the combination of a basestructure, a rotary driven sharpening miller supported erarm swingingly mounted on said base structure in alignment with the sharpening miller, a rotary driven gauging miller supported fromsaid base in the'path of the swinging bit holder, a dolly arm mounted to swing parallel to the bit holder arm, a spring pressed bush-ing on said dolly arm, means on said arm for depressing'said bushing on occasion, a rotatably mounted head on said bushing for engaging the cutting face of a bit upon said bit holder when the latter is swung to present such bit to said gauging miller and means to rotate said head during the gauging operation.

8. In a drill bit sharpening machine having a base structure supporting rotary driven sharpenarm for engaging the cutting face of a bit upon said bit holder when the latter is swung to present such bit to said gauging miller, and means to rotate said head during the gauging opera tion.

'9. In a drillbit sharpening machine having a base structure supporting rotary driven sharpening and gauging millers thereon, the combination, of a bit holder swingingly supported from the base and comprising a pivot shaft, means swinging laterally from said shaft for receiving and supporting a bit, a dolly arm also extending laterally to said shaft and adapted to swing parallel to said bit receiving and supporting means, a rotatably mounted head on said dolly arm for engaging the cutting face of a bit upon said bit holder when the latter is swung to present such bit to said gauging miller and means to rotate said head during the gauging operation.

10. In a drill bit sharpening machine having a base structure supporting rotary driven sharpthereon, a bit *hold- I 4- ening and gauging millers thereon, the combination of a bit holder swingingly mounted on the base in alignment with said millers and comprising a pivot shaft, a bit holder arm radially swingable about the axis of said shaft and adapted to receive a bit to be sharpened, a dolly arm also swingable about the axis of said shaft parallel to the bit holder arm, a spring-pressed bushing on said dolly arm, a cam bushing on said arm cooperable with said spring-pressed bushing for depressing the latter against the urgence of its spring, a rotatably mounted head on said bushing for engaging the cutting face of a bit upon said bit holder when the latter is swung to present such bit to said gauging miller at which time the spring-pressed bushing is depressed through rotary motion of the cam bush ing and means to rotate said head during the gauging operation.

11. In a drill bit sharpening machine having a base structure supporting rotary driven sharpening and gauging millers thereon, the combination of a bit holder swingingly mounted on the base in alignment with said millers and comprising a pivot shaft, a bit holder arm extending at an angle from said shaft and adapted to receive a bit to be sharpened, a dolly arm extending from said shaft to swing parallel to the bit holder arm, a spring pressed bushing'on said dolly arm, a cam on said arm for depressing the bushing, a collar supported from said bushing, a mandrel mounted in said collar and having a crank on one end, and a dolly mounted on the mandrel and adapted to engage and turn a bit on its supporting arm during the gauging operation.

12. In a drill bit sharpening machine, a bit holder mounted for'swinging movement, a dolly arm spaced from-and'swingable parallel to the bit holder and movable therewith, a dolly support pivotally mounted on the dolly arm and having a cam face, a spring-pressed cam mounted on the dolly arm, yieldable means acting upon the dolly support to urge it against the cam, a rotary headfor engaging a bit mounted on the bit holder upon depressive movement of the cam, and means for rotating said head during the gauging operation.

13.111 a drill bit sharpening machine, a bit holder mounted for swinging movement, a-dolly arm spaced from and swingable parallel to the bit holder and movable therewith, a dolly support mounted upon said dolly arm and comprising a pivotal bushing having a cam face, a springpressed cam having means for rotation mounted on the dolly shaft, yieldable means acting upon said bushing to urge it against the cam, a rotatable head supported from said bushing for engaging a bit mounted on the bit holder upon depressive movement of the cam, and means for rotating said head during the gauging operation.

14. A drill bit sharpening machine comprising a rotary driven sharpening miller, a bit holder swingingly mounted in alinement with said sharpening miller, a rotary driven gauging miller mounted in the path of said swinging bit holder, a rotatably mounted head for engaging the cutting face of a bit upon said bit holder when l the latter is swung to present such bit to said gauging miller, and means to rotate said head during the gauging operation.

JAMES F. MCCARTHY, JR.

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