US3594961A

US3594961A - Holder for sharpening twist drills

Info

Publication number: US3594961A
Application number: US865629A
Authority: US
Inventors: William C Reynolds
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-10-13
Filing date: 1969-10-13
Publication date: 1971-07-27
Anticipated expiration: 1988-07-27

Abstract

A holder for sharpening twist drills wherein the drill rests between sets of rollers mounted on a pair of parallel shafts. The shafts form part of a frame which pivots a limited amount about an axis perpendicular to the axis of the drill. A clamp is secured to the drill, and is provided with diametrically disposed shafts either one of which is insertable between a pair of fixed rods underlying the rollers which cause the drill to turn on its axis as the frame is moved arcuately. An adjustable stop controls the axial position of the drill. A modification involves the use of a slotted V-guide.

Description

United States Patent [72] Inventor William C. Reynolds P.O. Box 403. Morro Bay. Calif. 93442 [21] Appl. No. 865,629 [22] Filed Oct. 13. 1969 [45] Patented July 27. i971 [54] HOLDER FOR SHARPENING TWIST DRILLS 14 Claims, 8 Drawing Figs.

[52] U.S.Cl 51/219R [51] Int. Cl B24b 3/26 [50] Field ofSearch 51/219 R, 219 PC [56] References Cited UNITED STATES PATENTS 153,40l 7/1874 Haagen 51/219 Primary Examiner-Harold D. Whitehead Attorney-Lyon & Lyon ABSTRACT: A holder for sharpening twist drills wherein the drill rests between sets of rollers mounted on a pair of parallel shafts. The shafts form part of a frame which pivots a limited amount about an axis perpendicular to the axis of the drill A clamp is secured to the drill, and is provided with diametrically disposed shafts either one of which is insertable between a pair of fixed rods underlying the rollers which cause the drill to turn on its axis as the frame is moved arcuately. An adjustable stop controls the axial position of the drill. A modification involves the use ofa slotted V-guide.

HOLDER FOR SHARIENING TWIST DRILLS SUMMARY OF THE INVENTION This invention is summarized in the following objects: First. to provide a holder for sharpening twist drills which is inexpensive yet capable of presenting the drill to the grind wheel in such a manner that the two end faces, when finished, are identical with identical cutting edge angles and clearance angles, even when operated by unskilled persons.

Second, to provide a holder for sharpening twist drills which is readily adjusted to change the clearance angle of the drill to meet different drilling conditions.

Third, to provide a holder for sharpening twist drills which is capable of handling a wide range of drill sizes.

Fourth, to provide a holder for sharpening twist drills which utilizes a support defining a V-groove in which the drill or a shaft coaxial therewith is placed; the support providing openings through which a cross shaft secured to the drill or its coaxial shaft extends; the support being movable as a unit with the drill about an axis perpendicular to the drill and an end of the cross-shaft engaging a fixed member so that, on movement of the drill about the perpendicular axis, the drill is rotated about its axis thereby to generate a clearance angle.

Fifth, to provide a holder, as indicated in the preceding object, wherein the supports and drill are adjustable radially with respect to the perpendicular axis which includes novel means to effect precise axial adjustment of the drill in radial relation to the perpendicular axis.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of the holder for sharpening twist drills, with a portion of the grind wheel shown in section, the holder being shown in its initial or starting position by solid lines, and in its final position by dotted outline.

FIG. 2 is a side view of the holder, the parts being shown in their midposition.

FIG. 3 is a transverse sectional view, taken through 3-3 of FIG. 2.

FIG. 4 is a fragmentary sectional view, taken through 4-4 of FIG. 2.

FIG. 5 is a plan view, similar to FIG. 1, showing a modified construction of the holder.

FIG. 6 is a sectional view, taken through 6-6 of FIG. 8.

FIG. 7 is a fragmentary sectional view thereof, taken through 7-7 of FIG. 8.

FIG. 8 is a transverse sectional view, taken through 8-8 of FIG. 6.

Reference is first directed to FIGS. 1 through 4. The holder for sharpening twist drills includes a base 1 in the form of a rectangular plate. Extending upwardly from one end of the base is a journal post 2 which receives a pivot shaft 3. The upper end of the pivot shaft is joined to a crossbar 4.

Secured to the crossbar 4 and extending horizontally therefrom is a pair of parallel roller journal rods 5 and an adjustment rod 6 parallel to the journal rods. The extremities of the

rods

5 and 6 are joined to a second crossbar 7. Extending downward from the crossbar 7 is a supporting shaft 8, the lower end of which rides on the base 1. Mounted on or forming a part of the base I is a stop member 9 in the form ofa boss having an arcuate side terminating in stop ends 10 adjacent each side margin ofthe base 1.

Each journal rod 5 receives a set of rollers II. The rollers of each set are axially movable on their respective journal rod. The rods are spaced such that the rollers of each set are contiguous to the rollers of the other set but do not quite touch. The rollers form a channel to receive a twist drill l2, and is intended to accommodate drills ofdifferent diameter, for example, ranging from a sixteenth ofan inch in diameter to a half of an inch in diameter. The holder may, however, be adapted for larger or smaller drills.

The journal rods 5 are positioned equidistant at opposite sides of the vertical pivotal axis of the frame comprising the crossbar 4, journal rods 5, adjustment rod 6, and crossbar 7. As a consequence, the axis of rotation of the drill rod intersects the vertical pivotal axis of the frame.

The adjustment shaft 6 is screw threaded to receive a roller positioning wheel 13, which is engaged by a spring 14 to provide sufficient friction in order that the positioning wheel will remain wherever it may be placed. The positioning wheel engages the first roller of the adjacent set of rollers so that forward movement of this set of rollers toward the grind wheel may be determined by the positioning wheel 13.

A drill clamp is provided. The drill clamp is provided with an opening 16, forming a V-end, and is intended to receive a drill. The drill clamp is screw threaded to receive a screw shaft 17 which bears against a drill within the opening 16 so as to press the drill into the V-end thereof. A second shaft 18, in coaxial alignment with the screw shaft 17, extends in a diametrically opposite direction. By spreading the rollers axially, either

shaft

17 or 18 of the drill clamp may be extended between the rollers and toward the base I.

The base 1 is provided with a boss 19, located near the end of the base opposite from the journal post 2. The boss 19 is offset laterally with respect to the pivot shaft 3 and supporting shaft 8. Pivotally supported from the boss 19 for movement about a common axis is a pair of parallel bars 20, which slope upwardly and forwardly toward the pivot shaft 3. The bars are spaced to receive the tip of either

shaft

17 or 18, as indicated in FIG. 3.

Operation of the holder for sharpening twist drills shown in FIGS. 1 through 4 is as follows:

The holder is positioned with respect to a grind wheel 21 so that the grinding surface of the grind wheel coincides with a vertical or pivotal axis of the frame. A drill l2, placed between the sets of rollers is thus positioned so that its axis intersects the grind wheel at a point common to the axis of rotation of the frame.

The drill clamp 15 is secured to the drill and the rollers II are spread axially so as to form a slot through which the drill clamp and one of its shafts may extend downwardly for insertion between the parallel bars 20. The positioning wheel 13 is adjusted so that the surface of the drill is brought into contact with the grind wheel. The initial position is shown in FIG. 1 in which the supporting shaft 8 is in engagement with one of the stop members 9. When the frame and the drill 12 are moved from the position shown by solid lines in FIG. 1 toward the dotted outline position, the drill is caused to rotate around its axis. As a result, a drill face is generated and the drill face forms a predetermined clearance angle. During this operation, the drill is held in place by the operators hand. Between grinding operations, the position of the drill is changed by reversing the position of the drill clamp and inserting the other shaft between the bars 20.

The location of the drill clamp varies depending upon the length of drill; that is, the drill clamp is closer to the pivoted end of the frame when secured to a smaller drill. The slope of the bars 20 tend to compensate for location of the drill clamp so that whether a short drill or a long drill is being ground, the rotation of the drill and hence the clearance angle tend to remain constant.

It should be observed that while in most cases the axis of rotation of the frame coincides with the surface of the grind wheel, the holder may be displaced to change the configuration of the end face of the drill. Also, the angular relation of the holder with respect to the grind wheel may be altered should this be desired.

Reference is now directed to FIGS. 5 through 8. The construction here illustrated includes many parts of the .firstdescribed structure, which bear corresponding reference characters. The modified construction includes a baseplate 22, which rests on a table 23, and is capable ofannular adjustment. This is accomplished by extending the journal post 2 through the baseplate 22 to form a pivot 24, and securing the journal post to the table 23. The opposite end of the baseplate 22 is provided with a slot 25 which receives a clamp screw 26 extending into the table 23.

In place ofthe fixed stop 10, an adjustable stop 27 is provided. The adjustable stop includes a boss 28, extending upward from the baseplate 22. The boss 28 receives a horizontally extending screw shaft 29 which is provided with an adjustment wheel or knob 30 so that the screw shaft may be advanced or retracted endwise. Mounted on the screw shaft is a pair of stop discs 31, which may be adjustably secured by nuts 32. The stop discs 31 engage the supporting shaft 8 to limit its arcuate movement.

The pivot shaft 3 and frame which included the crossbars 4 and 7 and the

rods

5 and 6 of the previously described structure are utilized, the change ifany being one merely ofdimension. In place of the rollers 11, the frame receives a carriage 33, having end bars 34 provided with slotted ends which receive the rods 5. The end bars 34 are connected by a V- guide member 35, having a series of slots 36 therein.

The positioning wheel 13 and spring 14 of the firstdescribed structure are utilized and includes a finger 37, which engages the carriage in the same manner that the wheel 13 of the first-described structure engages one of the rollers.

The cartridge 33 may support a drill 12 directly as in the first described structure and utilize the drill clamp 15. Alternatively, the V-guide member 35 may support a journal shaft 38, provided with a cross rod 39 which serves the function of the drill clamp 15 and its shafts l7 and 18. A chuck 40 is secured to one end of the journal shaft 38 and receives the drill 12 to be sharpened. The end of the journal shaft 38 opposite from the chuck 40 may be provided with a counterbalance 41.

In place of the boss 19 and the parallel bars 20 of the firstdescribed structure, there is provided a drill turning lever 42, mounted on the baseplate 22 by means ofa pivot 43. The lever 42 includes a first arm 44, terminating in an end slot 45 which straddles the supporting shaft 8. The lever includes a second arm 46, the portion of which adjacent the pivot 43 extends upwardly so that the remaining portion may slope downwardly, as shown in FIG. 7. The downwardly sloping portion of the second arm is provided with a slot 47 which receives either end of the cross rod 39 or if the drill clamp 15 is used, either

shaft

17 or 18 is received by the slot 47.

, Operation of the construction shown in FIGS. 5 through 8 is essentially the same as the firstdescribed structure. The drillturning lever 42 operates essentially the same as the parallel bars 20. Because of the pivotal mounting of the lever 42, the second arm 46 and its slot 47 which is the equivalent of the parallel bars 20 need to slope downward toward the pivotal axis of the baseplate 22, rather than upwardly. If desired, the lever 42 may be provided with more than one pivotal axis by providing more than one hole to receive the pivot 43.

The present embodiments of this invention are to be considered in all respects as illustrative and not restrictive.

lclaim:

1. Means for holding twist drills for presentation to a grind wheel, comprising:

a. a frame having a pivotal axis located adjacent a grind wheel, the frame adapted for limited arcuate movement about its pivotal axis;

b. holding means carried by the frame defining a channel adapted to receive and support a drill with its longitudinal axis intersecting the pivotal axis of the frame and permitting rotation of the drill about its axis; said holding means forming transverse openings;

c. drill turning means adapted to be secured to the drill and to extend radially through the openings;

d. and means engaging the turning means to effect turning of the drill about its axis in correspondence with movement ofthe frame about its axis.

2. A twist drill holding means, as defined in claim 1,

wherein:

a. the holder means includes a pair of guide shafts and two sets of guide rollers slidable on the shafts to provide the openings for the receiving of the drill turning means. 3. A twist drill holding means, as defined in claimv l,

' wherein:

a. the holder means is in the form of a fixed V-channel slotted at intervals to receive the drill turning means.

4. A twist drill holding means, as defined in claim 1, which further comprises:

a. means for longitudinally adjusting the holding means and drill with respect to the grind wheel.

5. A twist drill holding means, as defined in claim 1,

wherein:

a. said frame includes a pair of parallel journal rods;

b. and said holding means includes sets of axially separable rollers mounted on said journal rods and forming said channel therebetween.

6. A twist drill holding means, as defined in claim 1,

wherein:

a. said frame includes a pair of parallel guide rods;

b. and said holding means includes a transversely slotted V- structure, the slots therein adapted to admit the drill turning means.

7. A twist drill holding means, as defined in claim 1,

wherein:

a. a base supports said frame;-

b. and the means engaging the turning means includes means forming a guide slot for receiving an end of said turning means therebetween.

8. Means for holding twist drills for presentation to a grind wheel, comprising:

a. a base member;

b. a vertical journal post at one end thereof;

c. a frame including a pair of guide bars and cross members at the ends thereof;

d. a member pivotally connecting one ofsaid cross members to the journal post;

e. a supporting post extending from the other crossmember to the base for arcuate movement thereon;

f. stop means for limiting the movement of the supporting post;

g. guide means axiallyslidable on the guide bars and defining an upwardly facing V-slot for rotation of a drill about its axis; said guide means having at least one transverse opening;

h. drill turning means having opposed arms selectively insertable through the transverse opening;

i. and means supported from the base for receiving either end of the opposed arms, thereby to turn the drill about its axis as the frame is pivoted about its axis.

9. A holder, as defined in claim 8, wherein:

a. said guide means is a set of rollers disposed in pairs.

10. A holder, as defined in claim 8, wherein:

a. said guide means is a V-block.

11. A holder, as defined in claim 8, wherein:

-a. said drill turning means is a clamp attachable directly to a drill.

12. A holder, as defined in claim 8, wherein:

a. said drill turning means includes a chuck for clamping a drill, a shaft secured to the chuck in coaxial relation to the drill, the opposed arms being carried by the shaft.

13. A holder, as defined in claim 8, wherein:

a. said receiving means is fixed to the base member, slopes upwardly toward the pivoted end of the frame, and defines a slot receiving a selected opposed arm.

14. A holder, as defined in claim 8, wherein:

a..said receiving means is pivotally connected to the base member intermediate its ends, and includes a first end engaged by the supporting post and a second end sloping downward toward the pivoted end of the frame, said second end defining a slot receiving a selected opposed arm.

Claims

1. Means for holding twist drills for presentation to a grind wheel, comprising: a. a frame having a pivotal axis located adjacent a grind wheel, the frame adapted for limited arcuate movement about its pivotal axis; b. holding means carried by the frame defining a channel adapted to receive and support a drill with its longitudinal axis intersecting the pivotal axis of the frame and permitting rotation of the drill about its axis; said holding means forming transverse openings; c. drill turning means adapted to be secured to the drill and to extend radially through the openings; d. and means engaging the turning means to effect turning of the drill about its axis in correspondence with movement of the frame about its axis.

2. A twist drill holding means, as defined in claim 1, wherein: a. the holder means includes a pair of guide shafts and two sets of guide rollers slidable on the shafts to provide the openings for the receiving of the drill turning means.

3. A twist drill holding means, as defined in claim 1, wherein: a. the holder means is in the form of a fixed V-channel slotted at intervals to receive the drill turning means.

4. A twist drill holding means, as defined in claim 1, which further comprises: a. means for longitudinally adjusting the holding means and drill with respect to the grind wheel.

5. A twist drill holding means, as defined in claim 1, wherein: a. said frame includes a pair of parallel journal rods; b. and said holding means includes sets of axially separable rollers mounted on said journal rods and forming said channel therebetween.

6. A twist drill holding means, as defined in claim 1, wherein: a. said frame includes a pair of parallel guide rods; b. and said holding means includes a transversely slotted V-structure, the slots therein adapted to admit the drill turning means.

7. A twist drill holding means, as defined in claim 1, wherein: a. a base supports said frame; b. and the means engaging the turning means includes means forming a guide slot for receiving an end of said turning means therebetween.

8. Means for holding twist drills for presentation to a grind wheel, comprising: a. a base member; b. a vertical journal post at one end thereof; c. a frame including a pair of guide bars and cross members at the ends thereof; d. a member pivotally connecting one of said cross members to the journal post; e. a supporting post extending from the other crossmember to the base for arcuate movement thereon; f. stop means for limiting the movement of the supporting post; g. guide means axially slidable on the guide bars and defining an upwardly facing V-slot for rotation of a drill about its axis; said guide means having at least one transverse opening; h. drill turning means having opposed arms selectively insertable through the transverse opening; i. and means supported from the base for receiving either end of the opposed arms, thereby to turn the drill about its axis as the frame is pivoted about its axis.

9. A holder, as defined in claim 8, wherein: a. said guide means is a set of rollers disposed in pairs.

10. A holder, as defined in claim 8, wherein: a. said guide means is a V-block.

11. A holder, as defined in claim 8, wherein: a. said drill turning means is a clamp attachable directly to a drill.

12. A holder, as defined in claim 8, wherein: a. said drill turning means includes a chuck for clamping a drill, a shaft secured to the chuck in coaxial relation to the drill, the opposed arms being carried by the shaft.

13. A holder, as defined in claim 8, wherein: a. said receiving means is fixed to the base member, slopes uPwardly toward the pivoted end of the frame, and defines a slot receiving a selected opposed arm.

14. A holder, as defined in claim 8, wherein: a. said receiving means is pivotally connected to the base member intermediate its ends, and includes a first end engaged by the supporting post and a second end sloping downward toward the pivoted end of the frame, said second end defining a slot receiving a selected opposed arm.