US2736147A - Michelson - Google Patents
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- Publication number
- US2736147A US2736147A US2736147DA US2736147A US 2736147 A US2736147 A US 2736147A US 2736147D A US2736147D A US 2736147DA US 2736147 A US2736147 A US 2736147A
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- United States
- Prior art keywords
- drill
- locating
- sharpening
- post
- guide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B3/00—Sharpening cutting edges, e.g. of tools; Accessories therefor, e.g. for holding the tools
- B24B3/24—Sharpening cutting edges, e.g. of tools; Accessories therefor, e.g. for holding the tools of drills
Definitions
- This invention relates to a drill sharpening fixture and more particularly to a device such as covered by my U. S. Patent No. 2,389,679, issued November 27, 1945.
- Fig. l is a plan view of the drill sharpening fixture embodying my invention.
- Fig. 2 is an elevational side View thereof.
- Fig. 3 is a front view in central vertical section.
- Fig. 4 is a sectional plan view on line 4-4 of FigfZ.
- Fig. 5 is an enlarged side view, in central vertical section, of the upper portion of said fixture.
- Fig. 6 is a front view of the said upper portion in central vertical section.
- Fig. 7 is a further enlarged view of said portion.
- Fig. 8 is a side view of a portion of the lower chuck, partly in central Vertical section.
- Fig. 9 is a side view of the said drill sharpening fixture showing the same with the positioning and magnifying means attached thereto.
- Fig. 10 is a side View of the upper portion of said fxture.
- Fig. 11 is an enlarged sectional top view on line 11-11 of Fig. 10.
- Fig. 12 is a plan view of the magnifying means embodied in my invention.
- Fig. 13 is a side view of the upper portion of the fixture showing the locating and magnifying means in a retracted position.
- Fig. 14 is an exploded perspective view of the various parts included in my improved locating and magnifying means.
- Fig. 15 is a side view of a resilient washer used in connection with my invention.
- the numeral 5 denotes the frame of my drill sharpening fixture
- 6 denotes a base portion thereof upon which there is rotatably mounted a spindle 7 having in its upper end a sleeve which is formed to provide a plurality of substantially resilient jaws 8 with tapered outer surfaces 9 which are engaged by a tapered annular surface 10 upon the inside of the chuck 9-a which includes a head 11 that is threaded to the said spindle.
- the upper end of the said sleeve is slit, as at 12, to render the jaws. 8 resilient when forced 2,736,147 Patented Feb. 28, 195,6
- the said spindle has an axial bore 14 in which there is contained a shank 15 of a chuck 15-a having a head 16 and jaws 17 mounted upon the end of said shank.
- a locating disc 18 is rigidly secured to the spindle 7 tol rotate therewith and is mounted within a slot 19 in the base portion 6.
- the said disc is provided around its periphery with a series of notches 20 that are engaged by a located detent 21 that is slidably mounted within a recess 22, in the base portion 6, and urged into contact with the said disc by a spring 23.
- the upper portion of the said fixture is provided with a lateral projection 24 having a bushing 25 fitting within an opening 26 therein and secured thereto in a predetermined position by means of a set screw 27.
- the said projection 24 is provided with a guide surface 28 which is disposed at an angle relatively to the vertical axes of the chuck 15-a and corresponding to the angle to which the cutting edge of the drill is to be formed.
- the said guide surface is also inclined rearwardly and is curved, as indicated at 28, to correspond with the degree, or angle, of the relief that is to be provided back of the cutting edge of the drill.
- An adjusting screw 29 is threaded to and coaxial with the spindle 7 and the said jaws, vshank and adjusting screw r are bored upon the axis of the opening in the chuck 15-a for the passage of a drill which is to be inserted in said chuck or removed therefrom.
- the said adjusting screw 29 abuts the end of the shank 15 so as to adjustably position said shank within the chuck 9-11.
- a locating member 30 that is retractably mounted against the rear surface of the projection 24 by means of a domed spring washer 31 which is secured'to the rear of the projection by a stud 32 having a head 33 which engages the said washer and forces it against the locating member 30 to securely retain said member in frictional engagement with the rear surface of the projection.
- the said locating member 30 has a projection 34 which extends laterally over the guide surface 28 and substantially parallel thereto, and the said projection has a straight locating edge 35 by means of which the cutting edges of the drill are located for a sharpening operation.
- the said magnifying glass preferably comprises a casing 36 in which there is mounted a suitable arrangement of lenses for the desired magnification.
- This casing has a projection 38 with an opening extending therethrough which receives a threaded post 39 for slidably mounting the said casing thereon, and a pair of clamping nuts 40 are provided on said post for clamping the magnifying glass therebetween and focusing it upon the cutting edges of the drill which are aligned by the locating edge 35.
- the post 39 has a base 41 which has an opening therein to receive a threaded projection 42 on the head 33, and an annular surface 43 is provided surrounding said opening to abut the head 33 and frictionally position the post on ⁇ the projection 24.
- the post is disposed at an angle to the base 41 and perpendicular to the guide surface 28 so as to support the magnifying glass parallel thereto.
- An abutment 44 projects from the post 41 and engages stop surfaces 45 and 46 at the end of the extension 24 for positioning said post 39 in its operative and retracted positions, and a clamping nut 47 is threaded to the projection 42 for securing the post 39 in its operative or inoperative positions.
- the guide member 30 has preferably an elongated slot 48 which permits sliding movement of said member, as well as rotating movement, upon the stud'32 and relatively to the extension 24.
- a drill indicated at 49, is secured between the jaws 17 of the chuck 15-a and positioned, by means of the adjusting screw 29, so that it will extend through the bushing 25 and project slightly above the guide surface 28.
- the locating member 30 is then moved to its operativeposition, as illustrated in Fig. 9, wherein the projection 34 thereof will be disposed upon the guide surface 28 and the locating edge 35 will extend across and slightly to one side of the center of the drill-end so as to locate the said straight edge in line with the bottom of the drill groove.
- the magnifying glass is then swung upwardly, until it is located in vits operation position by means of the abutment 44, and the clamping nut-47 is tightened to retain the magnifying glass in said position as shown in Figures 9 and 10.
- the magnifying glass and the locating member 30 are swung downwardly on the stud 32 to their inoperative positions, as shown in Fig. 13, and a suitable sharpening stone 52, indicated in dotted lines in Fig. 6, is then moved with a reciprocatory movement against the end of the drill and over the guide surface 28.
- This movement of the sharpening stone will be guided by the surface 28 so that said stone will sharpen, or form, a cutting edge and the relief in back of it at the correct angles.
- the disc 18 is rotated 180 until it is again positioned by the detent 21. This will bring to sharpening position the opposite cutting edge of the drill whereupon the sharpening operation with the sharpening stone is repeated.
- the head 16 of the chuck 15-a is rotated to open the jaws 17 and the drill may then be ejected through the top of the fixture by means of a wire inserted through the bores in the shank and adjusting screw.
- the locating disc 18 is preferably provided with four notches, so ⁇ as to accommodate drills or reamers having four cutting edges; however, any suitable number of notches may be provided to accommodate various types of drills or reamers which are to be sharpened in my fixture.
- my improved sharpening fixture may be adapted to drills of different sizes by providing a plurality of the bushings v25, each having a hole therein to accommodate a certain size of drill. Said bushings may be easily interchanged by loosening the set screw 27 and each of the said bushings may also be properly located so that their upper ends will be correctly positioned in alignment with the surface 28 by means of a positioning notch, indicated at 51, which cooperates with the end of the set screw 27 when the same is forced into said locating notch.
- the magnifying glass may be adjusted for the proper focus upon the end of the drill by simply manipulating the clamping nuts 40-40 upon the threaded post 39 until the said focus has been obtained.
- a device kof ⁇ the character described comprising a frame having a guide portion projecting therefrom, the said portion having ahole extending therethrough for receiving .a drill, av guide lsurface onisaid portion, a drill holder for holding a drill in said hole with its end positioned relatively ⁇ to said -guide surface, a stud projecting from the back of the said guide portion, a guide member slidable on said stud and having a projection with a straight edge thereon adapted to be positioned upon the guide surface -and -across -the said hole for locating the cuttingr edges of the drill relatively to the guide surface, means on said stud for frictionally retaining the guide member against vthe back of the guide portion, means permitting removal of the guide member yfrom the guide surface ywhile retaining it in ya vretracted position thereon, a supporting.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Drilling And Boring (AREA)
Description
Feb. 28, 1956 J-. MICHELsoN DRILL SHARPENING FIXTURE 2 Sheets-Sheet l Filed Jan. 5, 1952 #VVE/V707?.
JUL/(f5 N/CHELSONI Feb. 28, 1956 l J. MICHELsoN 2,736,147
DRILL SHARPENING FIXTURE Filed Jan. 5, 1952 Sheets-Sheet 2 /Nl/ENTOR.
JUL/U5 M/CHELS'O/V- /YTTOR/VEK United States Patent O DRILL SHARPENING FIXTURE v Julius Michelson, Worcester, Mass.
Application January 5, 1952, Serial No. 265,073
` 3 claims. (ci. 51-219) This invention relates to a drill sharpening fixture and more particularly to a device such as covered by my U. S. Patent No. 2,389,679, issued November 27, 1945.
It is an object of the present invention to provide certain improvements in the construction of such a drill sharpening fixture which will greatly facilitate the use, increase the accuracy of the fixture, and provide novel advantages over the construction disclosed in the said patent.
It is a further object of this invention to provide novel and efficient means for accurately locating a drill for a sharpening operation invsaid fixture.
It is a still further object of the present invention to provide magnifying meansfor facilitating the positioning of small size drills in an accurate manner.
Further objects and advantages of this invention will be more clearly understood from the following description and from the accompanying drawings in which:
Fig. l is a plan view of the drill sharpening fixture embodying my invention.
Fig. 2 is an elevational side View thereof.
Fig. 3 is a front view in central vertical section.
Fig. 4 is a sectional plan view on line 4-4 of FigfZ.
Fig. 5 is an enlarged side view, in central vertical section, of the upper portion of said fixture.
Fig. 6 is a front view of the said upper portion in central vertical section. j
Fig. 7 is a further enlarged view of said portion.
Fig. 8 is a side view of a portion of the lower chuck, partly in central Vertical section.
Fig. 9 is a side view of the said drill sharpening fixture showing the same with the positioning and magnifying means attached thereto.
Fig. 10 is a side View of the upper portion of said fxture.
Fig. 11 is an enlarged sectional top view on line 11-11 of Fig. 10.
Fig. 12 is a plan view of the magnifying means embodied in my invention.
Fig. 13 is a side view of the upper portion of the fixture showing the locating and magnifying means in a retracted position. v
Fig. 14 is an exploded perspective view of the various parts included in my improved locating and magnifying means.
Fig. 15 is a side view of a resilient washer used in connection with my invention.
As illustrated in the drawings, the numeral 5 denotes the frame of my drill sharpening fixture, and 6 denotes a base portion thereof upon which there is rotatably mounted a spindle 7 having in its upper end a sleeve which is formed to provide a plurality of substantially resilient jaws 8 with tapered outer surfaces 9 which are engaged by a tapered annular surface 10 upon the inside of the chuck 9-a which includes a head 11 that is threaded to the said spindle. The upper end of the said sleeve is slit, as at 12, to render the jaws. 8 resilient when forced 2,736,147 Patented Feb. 28, 195,6
ice
inwardly by the tapered surface on the head 11 and the said spindle has an axial bore 14 in which there is contained a shank 15 of a chuck 15-a having a head 16 and jaws 17 mounted upon the end of said shank.
A locating disc 18 is rigidly secured to the spindle 7 tol rotate therewith and is mounted within a slot 19 in the base portion 6. The said disc is provided around its periphery with a series of notches 20 that are engaged by a located detent 21 that is slidably mounted within a recess 22, in the base portion 6, and urged into contact with the said disc by a spring 23.
The upper portion of the said fixture is provided with a lateral projection 24 having a bushing 25 fitting within an opening 26 therein and secured thereto in a predetermined position by means of a set screw 27.
The said projection 24 is provided with a guide surface 28 which is disposed at an angle relatively to the vertical axes of the chuck 15-a and corresponding to the angle to which the cutting edge of the drill is to be formed. The said guide surface is also inclined rearwardly and is curved, as indicated at 28, to correspond with the degree, or angle, of the relief that is to be provided back of the cutting edge of the drill.
An adjusting screw 29 is threaded to and coaxial with the spindle 7 and the said jaws, vshank and adjusting screw r are bored upon the axis of the opening in the chuck 15-a for the passage of a drill which is to be inserted in said chuck or removed therefrom. The said adjusting screw 29 abuts the end of the shank 15 so as to adjustably position said shank within the chuck 9-11.
In order to facilitate accurately locating the cutting edges of a drill with respect to the guide surface 28, I provide a locating member 30 that is retractably mounted against the rear surface of the projection 24 by means of a domed spring washer 31 which is secured'to the rear of the projection by a stud 32 having a head 33 which engages the said washer and forces it against the locating member 30 to securely retain said member in frictional engagement with the rear surface of the projection. The said locating member 30 has a projection 34 which extends laterally over the guide surface 28 and substantially parallel thereto, and the said projection has a straight locating edge 35 by means of which the cutting edges of the drill are located for a sharpening operation.
In addition to the said locating member 30, I provide a magnifying glass for facilitating the locating cutting edges of a small drill which cannot be clearly seen with the naked eye; The said magnifying glass preferably comprises a casing 36 in which there is mounted a suitable arrangement of lenses for the desired magnification. This casing has a projection 38 with an opening extending therethrough which receives a threaded post 39 for slidably mounting the said casing thereon, and a pair of clamping nuts 40 are provided on said post for clamping the magnifying glass therebetween and focusing it upon the cutting edges of the drill which are aligned by the locating edge 35.
The post 39 has a base 41 which has an opening therein to receive a threaded projection 42 on the head 33, and an annular surface 43 is provided surrounding said opening to abut the head 33 and frictionally position the post on` the projection 24. lt will be noted that the post is disposed at an angle to the base 41 and perpendicular to the guide surface 28 so as to support the magnifying glass parallel thereto. An abutment 44 projects from the post 41 and engages stop surfaces 45 and 46 at the end of the extension 24 for positioning said post 39 in its operative and retracted positions, and a clamping nut 47 is threaded to the projection 42 for securing the post 39 in its operative or inoperative positions.
The guide member 30 has preferably an elongated slot 48 which permits sliding movement of said member, as well as rotating movement, upon the stud'32 and relatively to the extension 24.
In -the operation .of my invention, a drill, indicated at 49, is secured between the jaws 17 of the chuck 15-a and positioned, by means of the adjusting screw 29, so that it will extend through the bushing 25 and project slightly above the guide surface 28. The locating member 30 is then moved to its operativeposition, as illustrated in Fig. 9, wherein the projection 34 thereof will be disposed upon the guide surface 28 and the locating edge 35 will extend across and slightly to one side of the center of the drill-end so as to locate the said straight edge in line with the bottom of the drill groove. The magnifying glass is then swung upwardly, until it is located in vits operation position by means of the abutment 44, and the clamping nut-47 is tightened to retain the magnifying glass in said position as shown in Figures 9 and 10.
`The end of the drill is then viewed through the said magnifying glass and the shank is rotated in the chuck 9-a until the cutting edges of the drill are in alignment with the locating edge 35' as shown in dotted lines in Fig.V 12. The chuck head 11 is then rotated to tighten the chuck La and retain the drill in its adjusted position.
When the drill has been adjusted, as above described, the magnifying glass and the locating member 30 are swung downwardly on the stud 32 to their inoperative positions, as shown in Fig. 13, and a suitable sharpening stone 52, indicated in dotted lines in Fig. 6, is then moved with a reciprocatory movement against the end of the drill and over the guide surface 28. This movement of the sharpening stone will be guided by the surface 28 so that said stone will sharpen, or form, a cutting edge and the relief in back of it at the correct angles.
After one side of the drill has been sharpened, the disc 18 is rotated 180 until it is again positioned by the detent 21. This will bring to sharpening position the opposite cutting edge of the drill whereupon the sharpening operation with the sharpening stone is repeated.
1t will be understood that the proper cutting edge has been obtained on the drill when the sharpening stone is prevented, by the guide surface 28, from removing any more material from the end of the drill.
When both sides of the drill have been formed or sharpened as above described, the head 16 of the chuck 15-a is rotated to open the jaws 17 and the drill may then be ejected through the top of the fixture by means of a wire inserted through the bores in the shank and adjusting screw.
The locating disc 18 is preferably provided with four notches, so `as to accommodate drills or reamers having four cutting edges; however, any suitable number of notches may be provided to accommodate various types of drills or reamers which are to be sharpened in my fixture.
It is pointed out that my improved sharpening fixture may be adapted to drills of different sizes by providing a plurality of the bushings v25, each having a hole therein to accommodate a certain size of drill. Said bushings may be easily interchanged by loosening the set screw 27 and each of the said bushings may also be properly located so that their upper ends will be correctly positioned in alignment with the surface 28 by means of a positioning notch, indicated at 51, which cooperates with the end of the set screw 27 when the same is forced into said locating notch.
It is further pointed out that the magnifying glass may be adjusted for the proper focus upon the end of the drill by simply manipulating the clamping nuts 40-40 upon the threaded post 39 until the said focus has been obtained.
I claim:
1. A device kof `the character described comprising a frame having a guide portion projecting therefrom, the said portion having ahole extending therethrough for receiving .a drill, av guide lsurface onisaid portion, a drill holder for holding a drill in said hole with its end positioned relatively `to said -guide surface, a stud projecting from the back of the said guide portion, a guide member slidable on said stud and having a projection with a straight edge thereon adapted to be positioned upon the guide surface -and -across -the said hole for locating the cuttingr edges of the drill relatively to the guide surface, means on said stud for frictionally retaining the guide member against vthe back of the guide portion, means permitting removal of the guide member yfrom the guide surface ywhile retaining it in ya vretracted position thereon, a supporting. post swivellyfmountedupon said stud, `abutment Imeans engageable with -the said guide portion for positioning said post relatively to the guide surface, a magnifying 'glass mounted -on said lpost and means on said ,'post for positioning the magnifying kglass to focus it upon the end of the-drill.
.2. yIn combination with a =dri1l sharpening device includinga-frame having va guide portion with a guide surface and a hole A.extending therethrough for receiving a drill to be sharpened, the said guide portion 4having a back surface, a'drill-holder on said frame yfor holding a drill 4in -said hole with lits end positioned relatively to said guide surface, and a guide member on said guide portion removably positioned over said end of the drill for locating yit yrelatively "to the vguide surface, a post swivelly-mounted uponfthe said back surface of the guide portion and projecting upwardly therefrom, a magnifying glass -slidableion said post and ,'positionable over the said end of the drill and 'guide member, and means for adjusting said magnifying -glass along said post for focusing it upon said drill and guide member.
3. The subject matter setfforth in claim 2 wherein the post is retractible to carrythe magnifying glass over ythe end of the guide portion-into a 'position in which it is clearof a sharpening member being moved over the guide surface.
References Cited in the tile .of this patent UNITED STATES PATENTS 751,198 Parpart Feb. 2, 1904 1,308,248 McKenzie July 1, 1919 `1,' l88;039 Hinz Aug. '16, l1921 1,576,311 Des Jardins Mar. 9, 1926 1,582,014 Kendall Apr. 20, l1926 2,252,303 Oliver Aug. 12, '1941 2,291,729 Koett Aug. 4, 1942 2,389,679 Michelson Nov. 27, 1945 2,411,591 lRaney Nov. 26, 1946 2,511,055 Ganz June 13, 12950
Publications (1)
Publication Number | Publication Date |
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US2736147A true US2736147A (en) | 1956-02-28 |
Family
ID=3445484
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US2736147D Expired - Lifetime US2736147A (en) | Michelson |
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US (1) | US2736147A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3022609A (en) * | 1957-07-18 | 1962-02-27 | Leland Gifford Co | Drill sharpener and point thinner |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US751198A (en) * | 1904-02-02 | parpart | ||
US1308248A (en) * | 1919-07-01 | Archibald findlay mckenzie | ||
US1388039A (en) * | 1919-07-04 | 1921-08-16 | Hinz William | Drill-grinder |
US1576311A (en) * | 1921-03-25 | 1926-03-09 | Jardins Benjamin M Des | Mechanism for use in grinding twist-drill points and the like |
US1582014A (en) * | 1924-09-24 | 1926-04-20 | James L Barngrove | Device for holding drills for sharpening |
US2252303A (en) * | 1939-03-07 | 1941-08-12 | Edd C Oliver | Drill grinder |
US2291729A (en) * | 1940-01-16 | 1942-08-04 | Albert C Koett | Drilling apparatus |
US2389679A (en) * | 1944-02-14 | 1945-11-27 | Michelson Julius | Drill sharpening device |
US2411591A (en) * | 1944-05-06 | 1946-11-26 | William E Raney | Drill grinder |
US2511055A (en) * | 1945-04-13 | 1950-06-13 | Ganz Joseph | Device to sharpen twist drills |
-
0
- US US2736147D patent/US2736147A/en not_active Expired - Lifetime
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US751198A (en) * | 1904-02-02 | parpart | ||
US1308248A (en) * | 1919-07-01 | Archibald findlay mckenzie | ||
US1388039A (en) * | 1919-07-04 | 1921-08-16 | Hinz William | Drill-grinder |
US1576311A (en) * | 1921-03-25 | 1926-03-09 | Jardins Benjamin M Des | Mechanism for use in grinding twist-drill points and the like |
US1582014A (en) * | 1924-09-24 | 1926-04-20 | James L Barngrove | Device for holding drills for sharpening |
US2252303A (en) * | 1939-03-07 | 1941-08-12 | Edd C Oliver | Drill grinder |
US2291729A (en) * | 1940-01-16 | 1942-08-04 | Albert C Koett | Drilling apparatus |
US2389679A (en) * | 1944-02-14 | 1945-11-27 | Michelson Julius | Drill sharpening device |
US2411591A (en) * | 1944-05-06 | 1946-11-26 | William E Raney | Drill grinder |
US2511055A (en) * | 1945-04-13 | 1950-06-13 | Ganz Joseph | Device to sharpen twist drills |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3022609A (en) * | 1957-07-18 | 1962-02-27 | Leland Gifford Co | Drill sharpener and point thinner |
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