US643703A - Drill-grinding machine. - Google Patents

Drill-grinding machine. Download PDF

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US643703A
US643703A US73671299A US1899736712A US643703A US 643703 A US643703 A US 643703A US 73671299 A US73671299 A US 73671299A US 1899736712 A US1899736712 A US 1899736712A US 643703 A US643703 A US 643703A
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drill
holder
grinding
wheel
journal
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US73671299A
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Henry P White
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CHARLES D FULLER
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CHARLES D FULLER
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B3/00Sharpening cutting edges, e.g. of tools; Accessories therefor, e.g. for holding the tools
    • B24B3/24Sharpening cutting edges, e.g. of tools; Accessories therefor, e.g. for holding the tools of drills
    • B24B3/247Supports for drills

Description

0 0 m 0 2 h e F d e t n e t a P DRILL GRINDING MACHINE.
(Application filed Nov. 11 1899.)
2 Sheets-Sheet L (No Model.)
' lgvelgtor I Witlgesszsz sumo'ron, o. c
m: Nomys PETERS co. PH070 LITN\7.. WA
, Patented Feb. 20, I900.
H. P. WHITE.
DRILL GRINDING MACHINE.
(Application filed Nov. 11, 1899.)
2 Sheets-Sheet 2.
(No Model.)
Witgesses:
llgvelgton,
NlTED STATES ATENT HENRY P. WHITE, OF KALAMAZOO, MICHIGAN, ASSIGNOR TO CHARLES D. FULLER, OF SAME PLACE.
DRILL-GRINDING MACHINE.
SPECIFICATION forming part of Letters Patent No. 643,703, dated February 20, 1906.
Application filed November 11, 1899- Serial lilo. 736.712. (No model.)
To all whom, it may concern:
Be it known that I, HENRY P. WHITE, a citi-' zen of the United States, residing at the city of Kalamazoo, in the county of Kalamazoo and State of Michigan, have invented certain new and useful Improvements in Drill-Grinding Machines, of which the followingis a specification.
This invention relates to improvements in drill-grinding machines.
The objects of the invention are, first, to simplify the construction of drill-grinders that shall be adapted to grind different sizes of drills without special adjustment on account of the variations in the diameter of the drill; second, to provide an improved drillgrinding machine which shall give the properv variation to the clearance between the point and the periphery of the drill; third, to pro vide in a drill-grinder improved adjusting means to vary the clearance; fourth, to simplify the construction of a practical drillgrinding machine generally; fifth, to provide in a drill -grinding machine an improved holder which is adapted to fit and hold any size of drillin a practical manner; sixth,to provide in a drill-grinder improved means of adjusting or raising the drill from the holder for purposes of adjustment or the like.
Further objects will definitely appear in the detailed description to follow.
I accomplish these objects of my invention by the devices and means described in the specification.
Theinvention is clearly defined,and pointed out in the claims.
A structure embodying the features of my invention is fully illustrated in the accompanying drawings, forming a part of this specification, in which Figure 1 is a perspective view of a drillgrinding machine embodying the features of my invention. Fig. 2 is a plan view of the structure appearing in Fig. 1, showing details of construction.
detail sectional view of the adjustable bracket 0, taken on a line corresponding to line 3 3 of Fig. 1. Fig. 4isadetail sectional view through the adjustable tail-block, taken on a line corresponding to line 4 4: of Fig. 1. Fig. 5 is an enlarged detail end elevation view of the drill- Fig. 3 is an enlargedholder detached from its support, showing a drill of large size in position. Fig. 6 is an enlarged detail view of the adjustable lip-rest (1, looking at it from its inner edge. Fig. 7 is an enlarged detail sectional view of the drill-holderand supporting-bracket, taken on a line corresponding to line 7 7 of Fig. 1. Fig. Sis an enlarged detail sectional view through the holder and its adjustable support, taken on a line corresponding to line 8 8 of Fig. 1. Fig. 9 is an enlarged detail sectional view through the holder, its support, and the ad-- justin g means for varying the clearance,taken on a line corresponding to line 9 9 of Fig. 1. Fig. 10 is an enlarged detail sectional eleva tion through the holder and its adjustable tail-stock, taken on a line corresponding to line 10 10 of Fig. 1. Fig. 11 is an enlarged detail longitudinal sectional elevation through the lower end of the holder and its adjustable tail-stock, taken on a line corresponding to line 11 11 of Fig. 10.
In the drawings all of the sectional views are taken looking in the direction of the little arrows at the ends of the sectional lines, and similar letters of reference refer to similar parts throughout the several views.
Referring to the lettered parts of the drawings, A is the main frame of the machine,-carrying the usual driving-pulley B, on the shaft of which is supported a grinding-wheel B,
usually of emery. Projecting from the lower main frame A is a bracket A, bearing a cylindrical arm A. Extending at right angles to the plane of the face of the grinding-wheel on this arm A is an adjustable sleeve 0, bearing an arm 0. Extending back of said wheel and on the rear end of the arm 0' is a journalbearing 0, standing at an angle to the sleeve 0. A crooked arm D, with a journal at its lower end, fits into the journal-bearing O. The j ournal-bearing O is adjustable by means of an adjustable screw 1), the same being open at one side for this purpose. The bearing is fitted moderately tight, so that a little pressure is required to turn or rock the journal in its bearing. The axis of this journal extends upwardly and is at an acute angle to the face of the grinding-wheel, the point of support of the journal being back of the face of the said grinding-wheel. The arm D eX- tends from the journal upwardly and then is curved downwardly in front of the grindingwheel B, the same being formed into a loop to pass around the edge of the wheel, as clearly appears in Figs. 1 and 2. The outer end portion D of the arm D is formed into a seat or support for the drill-holder E. The 'under side of the drill-holder E is rounded at E to fit into the support D adj ustably. The handwheel J, with a screw J thereon, extends up through a transverse slot J in the bracket D into the portion E of the drill-holder E, as clearly appears in Fig. 8. A suitable washer is provided for the hand-wheel J and is adapted to restagainst the under side of the bracket D, which is formed on a curve to correspond with the curved seat between the drill-holder and the bracket D. This hand-wheel is adjustable for the purpose of permitting the drill-holder to be rocked in its seat. The curve on which it is rocked is an arc of a circle struck from the apex of the V-shaped longitudinal groove in the holder E. To regulate the adjustment, a transverse screw L, with knurl or thumb-nut L, is located transversely in the bracket D and is retained from longitudinal movement by a suitable screw 2', extending into an annular groove 2' therein.
The under side of the drill-holder E is provided with teeth L, like those of a worm-gear, to be engaged by the screw or worm L for positively controlling the adjustment of the drill-holder E.
Asuitable pointer g is provided on the front of the portion E of the drill-holder, and a scale g is provided on a bracket D to in dicate the adjustment of the drill-holder. The drillholder E has a V-shaped groove, preferably at an acute angle, as shown, in which the drills are laid to be ground. To facilitate the manipulation of the drill and remove the same from the V-shaped curve, I provide a transverse thin plate or arm a, pivoted at e", to strike up through a kerf on the under side of the drill-holder and raise any drill lying therein to a convenient position to be grasped by the fingers of the operator. A thumbpiece 6 is provided to actuate the same.
On the tail end of the drill-holderE is placed an adjustable tail-block F, which is retained in position by a clamp G conformed thereto, having a hand-screw G through the bottom to clamp it in position, as clearly appears in Fig. 10. In this block F is a shank H, adjustable therein by the hand or thumb nut F, and a fine adjustment is effected of the tail-block I and by the thumb-nut I on the screw I, which travels back and forth in the shank H. The clamp G and block F are secured together by small screws 70, so that the parts remain assembled during adjustment.
The apex of the Vshaped groove at the front end of the drill-holder E is in line of the axis of the journal 0, so that when the drill-holder swings from side to side it turns on this point as on a pivot. The left-hand side of the front end of the drill-holder E is out at an angle on a line nearly parallel with the face of the grinding-wheel. An adjustable lip-rest d is secured to the front end thereof and is adjustable by means of a screw and suitable slot. The lower portion of the drill-rest is curved slightly outward at d, as clearly appears in Figs. 5 and 6, to compensate for the difference in the angle of the grooves in large and small sized drills. The right-hand side of the drill-holder E is cut away to permit the holder to swing in grinding the drill without the holder itself coming in contact with the face of the grinding-wheel.
It will be observed that the face of the grinding-wheel B in its relation to the axis of the journal supporting the holder is at an angle, and therefore any parts supported in the drill-holder and rocked in front of the grinder will be ground to correspond to a portion of the surface of a cone, and that consequently a small drill laid within the drillholder will come near the apex of the cone and will be ground to conform to that portion of the cone, while a larger drill laid in the holder will not descend so deep into the angle of the holder and will be ground in a curve corresponding to the surface of the cone near the base, so that the size of the drill placed in the holder automatically comes to the proper position to secure the correct curvature for grinding the drill without any adjustment of the machine whatever, it only being necessary tobring the tail-stock into contact with the shank end of the drill, which is Very quickly and easily done. It will also be noted that the drill-lip rest (Z is capable of adjustment at such an angle that the front edge of the cutting-lip of the drill at its periphery will be in advance of the front edge of the cuttinglip near the center of the drill, and when the holder is properly adjusted this peripheral portion as it comes in contact with the grinding-wheel will be ground at a lesser angle of clearance than the portion near the center. The rocking motion given to the holder when oscillated causes the center portion of the drill to remain longer in contact with the grinding-surface of the wheel than any portion of the same size along the peripheral surface of the ground face of the drill, which action also tends to increase the angle of clearance at the center of the drill in a corresponding amount at each stage of its oscillation. This effect upon the drill is caused by the peculiar relation which the axial line of the angle of oscillation and the angle of the longitudinal line of the holder bear to each other and is of great advantage in securing a correct form to the drill-point.
The form of the drill above referred to is the one which is required and necessary for securing the best cutting effectof the drill, as it enables the center portion at each revolution to cut or advance as freely into the metal as the periphery. There is therefore no unnecessarystrain when the drill is ground secured. It will also be observed that by the.
adjustment of the device herein the drill holder is adjusted for the same relative clearance on all sizes of drills and there is no necessity for a separate and distinct adjustment for each size.
Having thus described myimproved holder, I desire to state that it can be considerably varied in its details without departing from my invention. The angle at which the journal-support stands or the position of the journal can be varied, though this will of course require'a variation of the other angles of the machine. It would be possible to manufacture and adjust the parts with the angle of the V-shaped holder opening at a right angle, or even more; but I have adjusted the parts to the form which seems to me to be most preferable. In the bottom of the holder I provide little thumb-openings f at each side, which are very convenient, but might be dispensed with. Other means might be provided for adjusting the holder in its rest, though the means I have shown seem to me to be most practical and, I believe, possess merit-s over any other. The same remarks apply as to the adjusting means I have shown of the tail-block for the holder. I provide the same with complete and elaborate adj ustments; but a simple tail-block of one piece could very likely be employed for ordinary work with very good success.
I have shown the machine with a base for adjustment to a bench for support; but I desire to state that the whole structure can be provided with a large base of its own to support it in position, and it is needless to remark that the form of the various parts can be considerably varied and still utilize the principle of my invention. It is also obvious that in constructing the machine it would be immaterial which parts bore the journals required and which the bearings therefor. A reversal of the same, as shown, would not depart from my invention.
Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-- l. Ina drill-grinding machine, the combination of the base A, carrying a suitable grinding-wheel B; a cylindrical arm A extending parallel to the axis of said grinding'wheel; a bracket 0 adj ustably supported on said arm A; an arm D with a journal standing at an angle to the face of said grinding-wheel extending into a journal-bearing box 0 back of the face of said grinding-wheel and extending upwardly and then downwardly in front of said grinding-wheel; a \l-shaped drill-holder rounded on its under side at E and resting in a curved bearing D on the arm D; a handscrew J extending upwardlythrough atransverse slot J in the bearing portion D and connecting by a screw-thread wi h the under side of the drill-holder to clamp the same when adjusted in its support; a transverse screw L controlled by a knurl or thumb-wheel L suitably supported in said bearing portion D, the screw-threads of which are adapted to engage worm-gear threads in the under side of the drill-holder for the purpose of adjusting the same; a pointer g on said portion E and a scale g on the portion D to indicate the position of the drill-holder; an adjustable tail block or stock for the drill-holder and a drill-lip rest secured to the forward end of the same, all coacting together substantially as described for the purpose specified.
2. In a drill-grinding machinethe combination of the base A, carrying a suitable grinding-wheel B; a cylindrical arm A extending parallel to the axis of said grinding-wheel; a bracket 0 adj ustably supported on said arm A; an arm D with a journal standing at an angle to the face of said grinding-wheel, extending into a journal-bearing box 0 back of the face of said grinding-wheel and extending upwardlyand then downwardly in front of said grinding-wheel; aV-shaped drill-holder E rounded on its under side at E and resting on a curved bearing D on the arm D; a handscrew J extending upwardly through a transverse slot J" in the bearing portion D and connecting by a screw-thread with the under side of the drill-holder to clamp the same when adjusted in its support; an adjustable tail block or stock for the drill-holder and a drill-lip rest secured to the forward end of the same, all coacting together substantially as described for the purpose specified.
3. In a drill-grinding machine the combination of the base A, carrying a suitable grinding-Wheel B; a cylindrical arm A extending parallel to the axis of said grinding-Wheel; a bracket 0 adj ustably supported on said arm A; an arm D with a journal standing at an angle to the face of said grinding-wheel, extending into a journal-bearing box 0 back of the face of said grinding-wheel and extending upwardly and then downwardly in front of said grinding-wheel; a V-shaped drill-holder E rounded on its under side at E and resting in a curved bearing D on the arm D; and means for adjusting the same in said support; an adjustable tail block or stock for the drillholder and a drill-lip rest secured to the forward end of the same, all coacting together substantially as described for the purpose specified.
4. In a drill-grinding machine the combination of the base A, carrying a suitable grinding-wheel B; a cylindrical arm A extendin g parallel to the axis of said grinding-Wheel; a bracket 0 adj ustably supported on said arm A; an arm D with a journal standing at an angle to the face of said grinding-wheel extending into a j ournal-bearing box 0" back of the face of said grinding-wheel and ex-- tending upwardly and then downwardly in front of said grindingwheel; a V-shaped drill-holder E supported on a bearing portion D of said arm D; an adjustable tail block or stock for the drill-holder and a drill-lip rest secured to the forward end of the same, all
ICC
coacting together substantially as described for the purpose specified.
5. In a drill-grinding machinc,the combination of a suitable base carrying a grindingwheel; a V-shaped drill-holder; an arm for carrying said drill holder which extends downwardly back of the face of said grinding-wheel terminating in a suitable journal provided with a suitable bearing, the axis of which, if extended upwardly, would form an acute angle with the face of the grindingwheel, coacting as specified.
6. In a drill-grinding machine the combination of a suitable base carrying a grindingwheel; a V-shaped drill-holder; a journal in a suitable bearing to support said drill-holder, the axis of which, if extended from the face of the grinding-wheel upwardly, would form an acute angle with the face of the grindingwheel, for the purpose specified.
7. In a drill-grinding machine the combination of a suitable base carrying a grindingwheel; a V-shaped drill-holder; a journal in a suitable bearing to support said drill-holder, the axis of which, if extended from the face of the grinding-wheel upwardly, would form anacut'e angle with the face of the grindingwheel; means of adjusting the support for said journal-bearing, for the purpose specified.
8. Inadrill-grindiugmachinethe combination of a suitable base; a grinding wheel thereon; a V-shaped drill-holder with a drilllip rest; a journal in a suitable bearing connected by suitable means to said drill-holder, the axis of which journal is in aline substantially through the apex of the V-shaped drillholder so that the drill-holder swings as on a pivot at that point, the said axis, if extended upwardly from the face of the drill would form an acute angle therewith, for the purpose specified.
D. In a drill-grinding machine the combination of a suitable base; a grinding wheel thereon; a V-shaped drill-holder with a drill-.
lip rest; a journal in a suitable bearing connected by suitable means to said drill-holder, the axis of which journal is substantially in a line through the apex of the V-shaped drillholder so that the drill-holder swings as on a pivot at that point, the said axis, if extended upwardly from the face of the grinding-wheel would form an acute angle therewith; means of adjusting the said holder to vary the angle of its V sides to the line of the axis of said journal, to vary the clearance and to set the holder to grind the circumference and Web of the drill at different angles for the purpose specified.
10. In a drill-grinding machine the combination of a base carrying a suitable grindingwheel, with a V-shaped drill-support located on one side of said grinding-wheel, said drillsupport being provided with means of oscillation which are placed on the opposite side of said grinding-wheel, the said means of oscillation being connected to the drill-support by a suitable arm passing across the edge of the grinding-wheel, for the purpose specified.
11. In a drill-grinding machine the combination of a suitable base; a grinding-wheel; a V-shaped holder supported on a suitable journal; a drill-lip rest d with an outwardlycurved lower portion d adjustably supported on the front thereof for the purpose specified.
12. In a drill-grinding machine the combination of a suitable base; a grinding-wheel; a V-shaped holder supported on a suitable journal; a drill-lip rest cl with an outwardlycurved lower portion d on the front thereof for the purpose specified.
13. In a drill-grinding machine, the combination of a drill-holder; a journal extending into a suitable bearing for supporting the same, the axis of which journal, if extended upwardly from the face of the grindingwheel, would form an acute angle therewith; a drilllip rest on one side of said V-shaped holder and to one side of a line bisecting the angle thereof whereby a drill placed within the same will have its cutting edge at the periphery in advance of the cutting edge at the center, whereby a different angle of clearance can be given to the peripheral and central portion of the drill for the purpose specified.
14. In a drill-grinding machine the combination of a base supporting a grinding-wheel, withaV-shaped holderprovided with means of oscillation, and having the angle of its sides so formed in relation to the angle of a line drawn through the center of oscillation,aud the plane of the grinding-surface of the wheel, as to cause a drill of any diameter when placed within the holder to rest at aproper distance above the apex of said holder so that if the line of oscillation, upon which the said holder swings, were extended, it would pass substantially through the apex of said holder, and cross the axial line of the drill at the required distance from its point, to secure the proper curvature of the ground surface of the cutting end of the drill, in combination with a curved bearing for supporting the said V- shaped holder, and means for adjusting the said holder to different positions in the curved bearing, for the purpose specified.
15. In a drill-grinding machine the combination of a base supporting a grinding-wheel, with a V-shaped holder provided with means of oscillation, and having the angle of its sides so formed in relation to the angle of a line drawn through the center of oscillation, and the grindingsurface of the wheel, as to cause a drill of any diameter when placed within the holder, to rest at a proper distance above the apex of said holder so that if the line of oscillation upon which the said holder swings were extended, it would pass substantially through the apex of said holder, and cross the axial line of the drill at the required distance from its point, to secure the proper curvature of the ground surface of the cutting end of the drill, for the purpose specified.
16. In a drill-grinding machine, a V-shaped holder provided with means of oscillation, Whose longitudinal line stands in such relation to the angle'of a line drawn through the center of oscillation as to cause the angular sides of said holder when oscillated, to change their relation to a vertical line, whereby a drill resting in such holder would be caused to rock upon its axial line when said holder is oscillated, to grind the drill with more clearance at the point than at the periphery, for the purpose specified.
17. In a drill-grinding machine, the combination of a V-shaped drill-holder; a suitable support therefor to allow the same to swing and means of adjusting the V-shaped support whereby the angles of the V-walls will be changed in relation to the support for said holder for the purpose specified.
18. In a drill-grinding machine, the combination of a V-shaped holder having an opening through its under side and a lever to act through said opening to raise the drills from the holder for ease of manipulation.
19. In a drill-grinding machine the combination of a V- shaped support E; a curved bearin g for supporting the same; a screw supported in said curved bearing and adapted to engage worm-gears on the under side of the holder for adjusting the same.
20. In a drill-grinding machine the combination of a Vshaped drill-support with a curved bearing therefor, the line of which curved bearing is struck from the apex of the said V-shaped support, and means for adj usting the said drill-support to different positions in the curved bearing, for the purpose specified.
21. In a drill-grinding machine, a V-shaped drill-holder having a recess near the front end in which a member may be operated for the purpose of more easily manipulating the drill.
22. In a drill-grinding machine, the combination of a grooved holder, with means positioned to rise from the bottom of said groove to raise the drill therefrom.
In witness whereof I have hereunto set my hand and seal in the presence of two witnesses.
HENRY P. WHITE. [L. s.]
Witnesses:
OTIS A. EARL, ALICE E. HOUGHTON.
US73671299A 1899-11-11 1899-11-11 Drill-grinding machine. Expired - Lifetime US643703A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2511055A (en) * 1945-04-13 1950-06-13 Ganz Joseph Device to sharpen twist drills
US2583159A (en) * 1948-10-08 1952-01-22 Nels H Swanson Drill grinding apparatus
US2632983A (en) * 1949-10-29 1953-03-31 Edward C Kapnick Drill end sharpening means
US2780894A (en) * 1954-04-28 1957-02-12 Nordberg Manufacturing Co Twist drill sharpening attachment for tool grinder
US3374587A (en) * 1966-03-16 1968-03-26 Simpkins Drill grinding attachment

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2511055A (en) * 1945-04-13 1950-06-13 Ganz Joseph Device to sharpen twist drills
US2583159A (en) * 1948-10-08 1952-01-22 Nels H Swanson Drill grinding apparatus
US2632983A (en) * 1949-10-29 1953-03-31 Edward C Kapnick Drill end sharpening means
US2780894A (en) * 1954-04-28 1957-02-12 Nordberg Manufacturing Co Twist drill sharpening attachment for tool grinder
US3374587A (en) * 1966-03-16 1968-03-26 Simpkins Drill grinding attachment

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