US2560454A

US2560454A - Apparatus for dressing convex surfaces on grinding wheels

Info

Publication number: US2560454A
Application number: US86254A
Authority: US
Inventors: Klopak Joseph
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1949-04-08
Filing date: 1949-04-08
Publication date: 1951-07-10
Anticipated expiration: 1968-07-10

Description

.uy l0, 1951 J, KLOPA'K' 2,560,454

APPARATUS FOR DRESSING CNVEX SURFACES ON' GRINDING WHEELS Filed April e, 1949 lllll I|| .K1 5MM rma@ m VH T NwM/A S www B Patented July 10, 1951 APPARATUS FOR DRESSING CONVEX SUR- FACES N GRINDING WHEELS Joseph Klopak, Newark, N. J., assigner Ato Gen eral Motors Corporation, Detroit, Mich., a corporation of Delaware Application April 8, 1949, Serial No. 86,254

Claims. (Cl. 125g-11) This invention relates to apparatus for dressing convex surfaces on grinding wheels, especially large radius curves on wheels of large diameter. In prior apparatus for dressing convex curves, the apparatus has been subject to vibration and, in order to get the center of curvature inside of the body of the Wheel, a large pivoted yoke has straddled a large portion of the wheel. This leads to undesirable bulk and expense.

An object of the invention, accordingly, is to provide a dressing apparatus which will avoid the above mentioned and other defects in prior devices. Another object is to provide.a compact but rugged dressing apparatus which will dress any selected convex curve across the periphery of a grinding wheel and be tree from vibration. Another object is to provide improved apparatus for locating the center of curvature about which the dressing tool travels inside the body of the wheel with provision for varying theradius of the curve produced without the need of a plurality of templates or formers.

In the drawings,

Fig. 1 is a plan View with a splash guard in section.

Fig. 2 is a view of parts of Fig. l in another position.

Fig. 3 is a perspective view of a blade and it follower,

Fig. 4 is a front view of Fig. 1.

Fig. 5 is a side view of Fig. 1 with a slide in section.

Fig. 6 is a plan view of a slide.

Fig. 7 is a perspective View of a gauge.

A main bracket 2 has a base flange 4 secured by screws 5 to the grinding wheel head. The bracket has a platform 8 on which is fastened a dovetail' guiding tongue II] whose center is in line with the central plane of the grinding wheel G. A slide I2 having guide rails is shiftable along the guide by a screw I4 threaded in a nut IB on the slide and journalled for rotation without endwise movement in a plate I8 fastened to the platform. Fastened in a recess of the slide I2 is a prole blade or template 2B having an arcuate guiding edge 22 engaged by the tip of a wedged shaped follower 24 formed on a stud 26 which secures the follower to a swinging diamond carrying arm 28. The follower has a flange 3D extending under an overhanging portion of the blade to hold the arm 2B down on the top of the plate l2. The follower and its ange are shiftable in an arcuate recess 32 of the slide I2. The enlarged front of the arm 28 has a threaded recess to adjustably receive a threaded diamond holder 34 in which a headed stud carrying a cutting tool or dressing diamond 36 is secured. A curved splash guard 38 having an opening for the arm 2B is guided between curved angle plates fastened on a main splash guard 40 which substantially iollows the outline of the slide I2.

The arm 23 is connected to a longer arm 42 by

parallel links

44 and 46 of equal length pivoted to each arm. The front end of the longer arm is pivoted to the slide I2 at one side of the wheel by a pivot stud 48 which is connected by a coil spring 5I! to a stud on the link 46. The spring holds the follower pressed against the profile blade. Pivoted to the arm 42 is a link 52 which is in turn pivoted in the fork of a yoke 54 adjust- .ably secured to one end of a piston rod 56 projecting from a cylinder 58 secured to the slide I2.

The pistonand cylinder unit oscillates the Varrn 42 about its pivot 48 and the parallel links cause the diamond carrying arm 28 to follow in parallelism. While this occurs the follower 24 is kept pressed against the prole blade thus controlling the motion of the diamond in an arc. The center of the curvature to be produced on the grinding wheel is inside the body of the wheel as indicated at C in Fig. 1; a plane perpendicular to the side ofthe grinding wheel through this point C will also pass through the center of the pivot stud 4S. This condition is maintained whatever the radius of the curvature to be produced. The curvature of the profile blade has the same center of curvature as Ythe curvature to be produced on the wheel but it has a larger radius.

Actuation of the screw I4 adjusts the slide I2 to locate the pivot 48 so that the center C which corresponds to it will come at the desired distance V from the periphery of the wheel. If a larger radius of curvature is desired, the slide I2 and its appurtenances are advanced towards the wheel and the diamond holder 34 is adjusted away from the wheel by the same amount by turning it in its threaded recess. The foregoing shifts the center C deeper into the wheel. If a smaller radius of curvature is desired, the slide I2 and its appurtenances are retracted from the wheel and the diamond holder is advanced the same amount. The prole blade serves as the guide for every radius desired. Its arcuate curvature is a known constant and its center of curvature is always at the center of curvature to be produced. I'he radius of the curvature to be produced is the distance from the diamond to the plane through the pivot 48 perpendicular to the side of the wheel. The apparatus is not limited to the dressing of arcuate curves. Other forms can be dressed by blades of the selected shapes.

Fig. 6 shows a set-up gauge 60 for accurate location of the diamond holder in the arm 28. The gauge (shown enlarged) will t around a portion of the diamond holder and when its arcuate edge 62 is placed against the end of the arm 28, the diamond holder can be shifted to make the diamond just meet the bottom wall 64. The amount that the diamond projects from the arm 28 is then the known depth of the gauge. The distance of the end of the arm from the edge of the blade is a known constant.

Iclaim:

1. In apparatus for forming a convex curve across the periphery of a grinding wheel, a long arm pivoted at one side of the grinding wheel, the pivot lying in a plane intersecting the wheel at right angles, a second and shorter arm normally in the central plane `of the grinding wheel, links pivotally connecting the arms in parallelism, a cutting tool at one end of the shorter arm, a follower on the shorter arm, a convex prole blade extending across the plane of the grinding wheel and having its center of curvature within the body of the wheel and in the aforementioned intersecting plane, a spring urging the follower against the blade, and means operatively connected to the longer arm for oscillating the longer arm around its pivot to traverse the follower along the blade.

2. In apparatus for dressing a convex surface of revolution on a grinding wheel, a movable arm normally in the plane of the grinding wheel, a cutting tool at one end of the arm and engageable with the grinding wheel, a prole blade having anrarcuate surface crossing the plane of the grinding wheel and having its center of curvature within the body of the grinding wheel, a follower on the arm and engaging said arcuate surface on the profile blade, a spring urging the follower into engagement with said arcuate surface, mechanism including a pivoted member and pivoted parallel links holding the movable arm radially of said arcuate surface and oscillating mechanism connected to said pivoted member.

3. In apparatus for forming a convex curve across the periphery of a grinding wheel, a long arm pivoted at one side of the grinding Wheel, a second and shorter arm beside the rst, links pivotally connecting the arms, a cutting tool at one end of the shorter arm and engageable with the grinding wheel, a prole blade having a convexed surface extending across the plane of the wheel and having its center of curvature within the body of the wheel, oscillating mechanism operatively connected to the longer arm for swinging said longer arm about its pivot, and a follower engaging the convexed blade surface for controlling the motion of the shorter arm.

4. In apparatus for forming a convex curve across the periphery of a grinding wheel, a slide, an arm pivoted to the slide at one side of the grinding wheel, a second arm, parallel links pivotally connected to the arms, the slide having an arcuate slot, a prole blade secured t0 the slide and overhanging the slot, a follower secured to the second arm and entering the slot to ride along the blade, a cutting tool carried by the arm, oscillating mechanism connected to the rst mentioned arm, an adjustment member for shifting the slide towards and from the periphery of the wheel to select the position of the center of oscillation, and an adjustable holder locating the cutting tool lengthwise of the second arm.

5. In apparatus for forming a convex curve across the periphery of a grinding wheel, a slide, an arm pivoted to the slide at one side of the grinding wheel, a second arm, parallel links pivotally connected to the arms, a profile blade secured to the slide and having an arcuate surface crossing the plane of the grinding wheel, a follower secured to the second arm and urged against the blade, a cutting tool adjustably secured to the second arm, mechanism operatively connected to one of said arms for oscillating the rst mentioned arm to cause the follower to traverse said arcuate surface, and feeding mechansm connected to the slide for shifting the slide towards or from the wheel to select the position of the center of oscillation.

JOSEPH KLOPAK.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 761,350 Barr May 31, 1904 1,089,455 Beam Mar. 10, 1914