US1892388A - Wheel dressing mechanism - Google Patents

Description

Dec. 27, 1932. .1. EDGAR WHEEL DRESSING MECHANISM I Y Original Filed Nov. 4. 1927 3 SheetsSheet 1 gain? 67501".-

IA'ITORNEYS Dec. 27, 1932. J.EDGAR 1,892,388

WHEEL DRESS ING MECHANISM Original Filed Nov. 4. 1927 5 Sheets-Sheet 2 Dec. 27, 1932. D R 1,892,388

WHEEL DRESSING MECHANISM Original Filed Nov. 4.1927 8 Sheets-Sheet 8 INVENTOR Jojm Ea? ar' ATTORNEYS Patented Dec. 27, 1932 UNITED STATES PATENT OFFICE JOHN EDGAR, OF ROCKFORD, ILLINOIS, ASSIGNOR TO BARBER-COLMAN. COMPANY, OF ROCKFORD, ILLINOIS, A CORPORATION OF ILLINOIS WHEEL DRESSING MECHANISM Original application filed November 4, 1927, Serial No. 230,966. Divided and this application filed January 9,

v 1928. Serial N 0. 245,351.

The present invention relates to improvements in dressing mechanisms for grinding wheels, and has particular reference to a novel dressing mechanism adapted to be incorporated in a grinding machine and'to auto- -matically and periodically dress the grinding wheel in timed relation to the cyclic operation of the machine.

One of the objects of the present invention resides in the provision of a new and improved dressing mechanismv for a grinding machine having a slide movable laterally of the grinding wheel, in which the dressing mechanism is supported on but is non-movable with the slide, and which is operable through movement of the slide in one, direction to dress the grinding wheel.

A further object resides in the provision in a grinding machine having a wheel with a V-shaped cutting periphery, of a novel dressing mechanism having tools for operating on the inclined sides of the grinding wheel and a tool for operating on the periphery .of the grinding'wheel, said tools serving to gradually change the form of the grinding wheel from a blunt contour into the desired predetermined contour, and to limit the position and form of the grinding wheel upon a relative approach feed between the grinding wheel and the dressing mechanism.

, A further object resides inthe provision of a novel mechanism having a pluralityof dressing tools adapted to be actuated in timed relation by means of asingle operating element to dress a plurality of separate grinding surfaces, and movable without interferencewith each other.

Other objects reside in the provision of a dressing mechanism of the above character in which each of the dressing tools is independently' adjustable, which is simple and inexpensive in construction, and which is positive and eflicient in operation.

A further object resides in the provision in a dressing mechanismhaving' a dressing tooland an actuating member therefor,of a clutch operatively int sed between said tool and said member, clutch being operative upon movement of said member in tion.

one direction and inoperative upon movement of said member in another direction.

Further objects and advantages will become apparent as the description proceeds.

In the accompanying drawings, Figure 1 is a fragmentary view partially in section of a grinding machine to which a dressing mechanism embodying the features of my invention has been applied, the front end of the dressing mechanism being shown in elevation.

Fig. 2 is a view similar to Fig. 1, but showing the dressing mechanism in rear eleva- Fig. 3 is the dressing mechanism taken along line 3-3 of Fig. l.

'Fig. 4 is a fragmentary view partially in section of the means for adjustably supporting the dressing tools.

Fig. 5 is a longitudinal sectional View of the clt ressing mechanism taken along line 55 of Fig. 6 is a sectional view taken along line 66 of Fig. 5.

Fig. 7 is a sectional view taken along line 7-7 of Fig. 1. I v

Fig. 8 is a diagrammatic view showing the contour of the grinding wheel at difierent stages of the grinding operation.

While the invention is susceptible of various modifications and alternative constructions, I have shown in the drawings and will herein describe in detail the preferred embodiment but it is to be understood that I do not'thereby intend to limit the invention to the specific form disclosed, but intend to cover all modifications andalternative constructions falling within the spirit and scope a fragmentary detailed view of ing machine comprises a base 10 having a vertical column 11. A head stock slide 12 which supports a grinding wheel 13 adapted to be driven through a shaft 14, a pulley 15 and a belt 16, is adjustably mounted on the column 11. Preferably, this adjustment is provided by anon-rotatable feed screw 17 depending from the slide 12, and by a rotatable nut 18 anchored in the column 11 and having a threaded engagement with the screw 17, said nut being adapted to be rotated through any suitable means (not shown).

While the dressing mechanism may be adapted to operate on a large variety of grinding Wheels, in the present instance, the grinding wheel 13 is flat in form, and has a beveled or V-shaped grinding periphery comprising oppositely inclined side faces 19 and 20, and a flat intermediate peripheral face 21, thus adapting the grinding wheel for grindin V-shaped screw threads 22 (see Fig. 8).

ounted on the base 10 for movement toward and from the column 11 perpendicular to the plane of the grinding wheel 13-is an indexing slide 23. A traverse slide 24 adapted to support a work holder (not shown) is mounted on the index slide 23 for reciprocation in the plane of the grinding wheel 13. While the specific means for actuating the slides 23 and 24 is not disclosed herein, it will be understood that movement of the slide 24 carries the work across the grinding wheel 13 to grind the threads 22 individually, and that movement of the slide 23 in opposite directions serves respectively to index the threads 22 successively into grinding position, and to return the work to the starting position for the commencement of a deeper cut.

The dressing mechanism comprises a suitable base 25 mounted on the slide 24 for long itudinal and lateral movement therewith.

he upper surface of the base 25 is formed with dove-tailed guides 26 on which a slide 27 is secured by suitable gib plates 28. The

slide 27 is rigidly secured against movement with the slide 23 laterally of the base 10 by means of a rearwardly extendin arm 29 hav- I ing a depending finger 30 slida ly engaging in a spline groove 31 in the upper surface of a block 32 secured across the front of the colum 11. By this construction, the dressing mechanism is retained in the plane of the grinding wheel 13 for movement into and out of operative position with the slide 24 regardless of the lateral position of the slide 23."

Secured to the rear side of the slide 27 "is a depending V-shaped bracket 33 having: a bearing 34 at its apex in which a stub shaft 35 is rotatably mounted. The inner end of the shaft 35 has a collar 36 secured thereto, and abutting against'the end of the bearing 34, and isformed with a spur gear 37 which meshes with a rack gear 38 suitably secured to the underside of the base 25 and extending transversely thereof. The outer end of the shaft 35 is formed with an enlargement 39 having a plurality of peripherally spaced and inclined notches or cam faces 40. A suitable clutch sleeve 41 is rotatably mounted on the shaft 35 between the adjacent end of the bearing34 and the enlargement 39, and has an annular flange 42 disposed about the periphery of said enlargement.

A plurality of balls 43, one in each instance, are freely disposed in the notches and are retained therein by means of an end cap 44 fitting over the open end of the flange 42. It will be-noted that when the shaft 35 is rotated in a clockwise direction as viewed in Fig. 6, as it is when the base'25 is moved forwardly from the column 11, the balls 43 will move into wedging engagement with the notches 40 and the flange 42 so as to effect a clutch connection between the shaft 35 and the sleeve 41; and that when the shaft 35 is rotated in a counter-clockwise direction, as it is when the base 25 is moved rearwardly toward the column 11, it will. rotate freely without rotating the sleeve 41.

Keyed on the sleeve 41 is a spur gear 45 which meshes with a pinion 46 k'eyed to a stub shaft 47 journaled in the bracket 33. The pinion 46 is formed integral on one end with an eccentric 48 which is rotatably disposed in a bifurcated end 49 of a bell-crank lever 50 keyed to the outer end of a shaft 51 journaled in the slide 27 The shaft 51 extends through the slide 27, and has an arm 52 secured to its front end. A suitable dressing tool 53 is adjustably secured in a socket 54 in the free end of the arm 52. In the present instance, the dressing tool 53 has 9. diamond point 55, and is adapted to be adjusted by means of a screw 56 threaded into the inner end of the socket 54. The diamond point is arranged for oscillation in a vertical plane across the peripheral face 21 of the grinding wheel 13 to dress the latter.

One arm of the lever 50 is formed with a gear segment 57 which meshes with a gear segment 58 rigidly secured to one end of a shaft 59. The latter is suitably journaled in a bearing' 60 formed in an upstanding bracket 61 at the rear edge of the slide 27. A spur car 62 is keyed to the right end of the sha t 59, and meshes at opposite sides with, two rack gears '63 and 64' provided on suitable dressing tool slides 65 and 66, re-

"Preferably, the gear racks 63 and 66, and extend longitudinally along the rear side edges thereof.

The slides 65 and.66 carry suitable dressing tools 67 and 68 having diamond points 69 and 70 adapted respectively to dress the cutting faces 19 and 20 of the grinding wheel 13. Preferably, the dressingtools 67 and 68 are mounted in suitable sockets 71 formed in laterally projecting lugs 72 and 73 on the ormedint'egral with the slides 65 right sides of the slides 65 and 66, and can be adjusted therein by means of suitable adjusting screws 74 and 7 5.

The slides 65 and 66 are mounted for reciprocation on suitable brackets 76 and 77 adjustably secured to the bracket 61. In the present instance, each bracket 76-77 is provided with a guide strip 7 8 having V-shaped guideways 79 in opposite longitudinal edges. Each slide 6566 is longitudinally recessed in its rear face to form spaced flanges 80 having V-shaped guideways 81 directly opposed to the guideways 7 9. A plurality of balls 82 are disposed between the guideways 79 and 81. Preferably, the balls 82 are held in spaced relation in suitable retaining strips 83 which extend between the guideways 79 and 81, and the ends of which are bent over the ends of the slides 66. The brackets 7 6 and 77 are provided with arcuate arms 84 and 85 respectively, of which the arm '84 is ad just'ably clamped to a plate 86 on the bracket 61 by means of a bolt 87. The arm 85 is rigidly secured to the plate 86 asby means of screws, and the two are secured to the bracket 61 by means of a bolt 87. To this end, the arms 8485 are formed with T-slots 88 respectively engaging the heads of the bolts 87.

It will be evident that as the base 25 is moved away from the column 11, the eccentric 48 will be rotated in a counterclockwise direction as viewed in Fig. 2. This will oscillate the shafts 51 and 59 to reciprocate the dressing points 556970 respectively across the grinding faces 192021. The relative movement of the dressing points is so timed that there is no interference. By adjusting the brackets 84 and 85 to the proper angle, the desired contour will be provided on the grinding wheel. As the grinding wheel 13 is fed downwardly its contour will gradually approach the final predetermined contour, the dressing points 55'697O serving to limit the depth and shapeof the cut. Thus, at the beginning of the grinding op-' eration, see a in Fig. 8, the grinding wheel 13 is blunt, but cuts the full Width of the thread 22. As the grinding wheel cuts deep- .er and deeper, see b and c in Fig. 8, its form becomes more pointed. It will be evident that the grinding is performed mainly by the extreme periphery of the wheel 13. The

dressing tool 55 limits the depth of the cut.

I claim as my invention: 1. A dressing mechanism having, 1n combination, a base, a support mounted for relative reciprocation or. said base, a dressing tool movably mounted on said support, means for operating said dressing tool, said means comprising a one direction clutch, one element of said clutch being connected to a drive pinion, and arack gear on said base and in e'sfh-with said pinion, whereby said dressg t 001 will be operated upon relative moveni'ent of said support on said base in one di gear, said rack extending in the directionof relative movement of said support, a clutch member on said shaft, a clutch sleeve on said shaft, coacting means between said clutch member and said clutch sleeve, said last mentioned means being effectual to drive said sleeve upon rotation of said shaft in one direction but being ineflectual to drive said sleeve upon rotation of said shaft in the other direction, a wheel dressing element movably mounted on said support, and means operatively connecting said sleeve to said wheel dressing element for actuating the latter upon rotation of said sleeve.

3. A dressing mechanism having, in combination, a base, a support mounted for relative reciprocation on said base, a plurality of dressing tools movably mounted on said support, and means for operating said dressing tools, said last mentioned means comprising a one direction clutch operably connected to said base to effect movementof said tools upon relative movement of said support in one direction and to be ineffectual upon relative movement of said support in the other direction on said base.

4. A dressing mechanism having, in combination, a base, a support mounted for relative sliding movement on said base, a shaft journaled in said support, a gear rack on said base, said rack extending in the direction of relative movement of said support, gear means connecting said shaft to said rack, a clutch element on said shaft, a second clutch element, coacting means between said clutch elements, said last mentioned means being effectual to drive said second clutch element upon rotation of said shaft in one direction but being ineffectual to drive said second clutch element upon rotation of said'shaft in the otherdirection, a wheel dressing tool movably mounted on said support, and means operatively connecting said second'clutch element to said wheel dressing tool,

5. A dressingmechanism comprising, in combination, a base, a support mounted for relative reciprocation on said'base, a shaft rotatably mounted on said support, a dress 6. A dressing mechanism comprising, in

combination, a support, a pair of tool slides mounted for reciprocation on said support, said tool slides being angularly adjustable on said support, a shaft in said support, gear means operatively connecting said shaft to said slides, a second shaft, a laterally extending holder having a dressing tool mounted combination, a support, a pair of tool slides mounted for reciprocation on said support, said tool slides being angularly adjustable on said support, a shaft in said support, gear means operatively connecting said shaft to said slides, a second shaft in said support, gear segments on said shafts in mesh with each other, a laterally extending holder having a dressing tool mounted on said second shaft, one of said gear segments having a bifurcated arm, an eccentric disposed in said bifurcated arm, and means for rotating said eccentric.

8. A dressing mechanism comprising, in combination, a support, a pair of guides having bracket arms arcuately adjustable about a common center on said support, two slides mounted respectively on said guides, two dressing tools one operatively mounted on each slide, two longitudinal gear racks one on each slide, a gear disposed between and in mesh with said racks, said gear being rotatable on said center, a shaft for rotating said gear, and means for oscillating said shaft.

9. A dressing mechanism comprfsing, in combination, with a grinding wheel adapted to have a V-shaped contour and a support for the grinding wheel, a base reciprocable relative to said support in the plane of the grinding wheel and also transversely of the grinding wheel, means for effecting a feeding movement of said grinding wheel toward said base, a dressing support transversely slidable on said base, means for holding said support against movement relative to said first mentioned support transversely of said grinding wheel, a plurality of dressing tools mounted on said dressing support in position respectively to dress opposite side faces and the peripheral face of said grinding wheel, and means operable through relative movement between said dressing support and said base for actuating said dressing tools across the respective faces of said grinding wheel.

10. A dressing mechanism comprising, in combination, a support, ashaft rotatably mounted in said support, a gear segment on said shaft, means supporting a dressing tool 0nd shaft rotatably mounted in said support, a bifurcated arm on said second shaft, said arm having a gear segment in mesh with said first mentioned gear segment, means supportmg a dressing tool operatively connected to said second shaft, an eccentric journaled in said support and operatively disposed in said bifurcated arm, and means for rotating said pccantric whereby to oscillate said dressing 11. A dressing mechanism comprising, in

combination, a support having an annular ring with a concentric arcuate slot, a bracket having an a-rcuate arm, said arm having an arcuate projection fitting in said slot for angular adjustment and having an arcuate T-slot opening laterally through said proection, means ooacting with said T-slot for securing said arm in position of adjustment to said ring, said bracket having a guide, a slide reciprocable on said guide, anti-frict1on bearings disposed between said guide and said slide, gear means for reciprocating said slide and a dressing tool adjustably mounted on said slide.

12. A dressing mechanism comprising, in combination with a grinding wheel and a support for the grinding wheel, a base reciprocable relative to said support transversely of the grinding Wheel axis. and also parallel to said axis, means for effecting a relative feeding of said grinding wheel toward said base, a dressing support relatively operatively connected to said shaft, a sec- In testimony whereof, I have hereunto affixed my signature.

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