US2919689A

US2919689A - Radius dresser

Info

Publication number: US2919689A
Application number: US614019A
Authority: US
Inventors: Edwin J Burkhart
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-10-04
Filing date: 1956-10-04
Publication date: 1960-01-05
Anticipated expiration: 1977-01-05

Description

Jan. 5, 1960 E. J. BURKHART RADIUS DRESSER 2 Sheets-Sheet 1 Filed Oct. 4, 1956 INVEN TOR. [ow/N (2' 50/9/1416??? BY Q4 6% 52 9% 1% 'ra/r/ws'n- Jan. 5, 1960 E. J. BURKHART RADIUS DRESSER 2 Sheets-Sheet 2 Filed Oct. 4 1956 United States Patent Ofiice 2,919,689 v Patented Jan. 5, 1960 RADIUS DRESSER Edwin J. Burkhart, North Olmsted, Ohio Application October 4, 1956, Serial No. 614,019 4 Claims. Cl. 125-11 The invention relates to radius dresssers, sometimes in more limited applications referred to as grinding wheel dressers.

As is known to those skilled in machine shop practice, objects having certain surface contours which are most conveniently shaped by grinding are finished by means of a grinding wheel having a contour complementary to that of the face to be ground. The simplest exemplification of this procedure is the formation, for example, of'a concavity on a surface by the use of'a grinding wheel having a convexity on its exterior having a radius of curvature equivalent to the radius of curvature' of said concavity.

' It will be obvious that continued use of such grinding wheel in the finishing of a large number of identical parts will cause the wheel periphery to gradually depart from dimensional accuracy, and it is desirable to provide a simple, rapid, and economic means for restoring'the wheel periphery to its original contour. This is known in the art as wheel dressing or radius dressing and a device whereby the purpose can be accomplished is commonly termed a radius dresser.

It is an object of the present invention to provide a radius dresser of simple construction, sothat it can be manufactured at a relatively low cost, and can be operated by anyone relatively unskilled as a result of the adjusting and guiding structure which I have provided.

Further objects and advantages of the invention will be apparent upon a study of the following specification, in conjunction with the accompanying drawings, in which: 1

Fig. 1 is a side elevational view of the radius dresser exemplifying one embodiment of my invention.

- 'Fig. 2 is a top plan view of the device shown in Fig. 1.

Fig. 3 is an end elevational view as seen from the left side of Fig. 1.

Fig. 4 is a sectional view taken on the line 44 of Fig. 1'.

Fig. 5 is a view similar in most respects to Fig. 4, but showing a somewhat modified form of the invention.

Referring now to Figs. 1 to 4, I show a radius dresser having a base which is movable on a fixed bed plate 11. A transverse supporting bar 12 carries on its top surface a template or guide member 13, the bar 12 and template 13 being fixed to bed plate 11 by means of two machine bolts 14 which extend upwardly through aligned apertures in the bed plate, the bar, and the template, and are tightly clamped by knurled knobs 15. j

The working surface 13a of template 13 is machined to a contour equivalent to the peripheral contour of the wheels to be dressed. In the present instance, said Working surface is shown asa segment of a circle, and the grinding wheel 16 shown in fragmentary outline in Fig. 1 has a peripheral edge face groove cut to the same concavity as the curvature of the surface 13a of the template. The axis of rotation of the Wheel is fixed with respect to bed plate 11.

Supported on base 10 is a movable carriage 17 having a dove-tailed shoe 17a which is slidable in a complementary groove 18 in the base. The carriage may be moved to the right or left (Figs. 1 and 2) and may be adjustably fixed in any convenient way in the groove, as by a set screw (not shown) or may even be advanceable and retractable in more elaborate fashion as by a worm and gear or rack and pinion (not shown). The shoe is intended to be adjustably fixed in any desired position, within limits, forwardly and rearwardly with respect to the fixed template, as will appear.

Fixed to the carriage 17 by means of a pin 19 is a post 20 which carries fixed thereto a cutting tool 21 which has a hardened cutting point 21a, for example a diamond or tungsten carbide point. This is held in place in any convenient way, for instance by the set screw 24.

A pair of follower pins 25 depend within the hollow base it} far enough to make contact, when in working position, with face 13a of the template. These pins are spaced one on each side of a vertical plane in which plane lies the axis of tool 21. It can be seen that the operator may move the base 10 until pins 25 make contact with the template face 13a. If the base then be moved to the right or left; the carriage 17, the post 20, and the tool 21 will of course travel with it through a segment of a curve equivalent to the curvature of template face 13a, and the tool point- 21a will trace a curve of equivalent radius as long as the tool point is disposed directly above an imaginary line joining the contact points of pins 25 with face 13a.

Extending up from base 10 is a dimensional reference point consisting of a pin 26. Protruding laterally from the same side of shoe 17 is another reference point consisting of a pin '27. In the position shown in Fig. 1, and in an actual working embodiment I have constructed and used,

pins

26 and 27 are exactly one inch apart when tool point 21a is exactly above the line between follower pins 25, and therefore this position can be immediately duplicated at any time by inserting a one-inch block or other dimensional guide on base 10, in contact with pin 26, and then moving shoe 17 to the left (Fig. 1) until pin 27 makes contact with the block.

Obviously if pin 27 be moved to within one-half inch of pin 26 (again using a measuring block) then tool 21 will finish a wheel having a radius one-half inch less than the radius of the template, and if pin 27 be moved to contact with pin 26 by movement of shoe 17, the wheel will be of a radius one inch less than the radius of the'working face of the template. Other variations in radii of wheels being dressed may be accommodated by movement of shoe 17 to the right or left from the position shown in Figs. 1 and 2, inserting in each case the desired dimensioning block between

pins

26 and 27. A leeway of several inches in grinding wheel diameters can be accommodated in this way.

The device of Figs. 1 to 4 is operated as follows. Assume that when the shoe 17 is moved to the left (Figs. 1 and 2) until pin 27 contacts pin 26, the tool 21 is positioned to make dressing contact with a wheel of six inches radius. The tool point 21a should be disposed at the same height as the axis of rotation 22 of the wheel 16. The wheel is rotated and the dresser is moved laterally, maintaining pins 25 in contact with face 13a of the template. 1

If the next wheel to be dressed has a radius of seven inches, the shoe is unclamped and moved rearwardly (to the right in Fig. 1). A one-inch spacing block is inserted to the right of pin 26, in contact with it, and

the shoe is moved forwardly until pin 27 contacts the block. The shoe is then secured in place and the block is withdrawn. The tool is now set one inch further from the axis of rotation of the wheel. The manner of deter-- mining tool positions for other dimensions is now obvious.

I have provided means for converting my radius dresser so as to provide a tangential or transversely lineal dressing cut, which is the type desired for the ordinary grinding wheel having a plain cylindrical periphery, that is to say, neither convex nor concave. While such conversion could be effected by substituting for template 13 another template having a rectilineal working face, I can accomplish the same purpose much more readily, without substitution of the template, in the following manner. Referring to the drawings, it will be observed that the upper face of bar 12 has been provided With a pair of parallel grooves 30 and 31 equispaced on either side of the axis of tool 21. These grooves are adapted to receive stop blocks 32 which can be very readily slid into or out of their respective grooves. When either stop block is in position, it is just contactable with the outer face of a follower pin 25, and in this position the tool 21 is exactly on center with respect to follower pins 25. In this position, if block 32 is in its groove and in contact with the adjacent pin 25, the bed plate 11 and the complete assembly can be moved transversely in the direction of the arrow X (Fig. and the tool 21 will make a dressing cut straight across a Wheel periphery in said direction, For this purpose it may be noted that only the stop block 32 need be in place, but if it is desired to make a return cut, the block 33 must be inserted for transverse movement in the direction of the arrow Y.

Such lateral movement of the bed plate can be achieved if it is mounted on a machine frame provided With a lateral mechanical or hand feed (not shown). To insert or remove the blocks 32 and 33, or either of them, requires only a moment, after the base assembly is lifted away from bed plate 11. Dimensioning the assembly for wheels of different radii is done as heretofore described.

What I claim is:

1. In a radius dresser of the type provided with fixed supporting means having a planar upper surface, above which a wheel to be dressed is rotatable in a vertical plane on a fixed axis, means for dressing the peripheral edge face of said Wheel comprising a template fixed above said supporting means, said template having an edge shaped to the contour to be reproduced on said Wheel edge face, a base member in sliding contact with said planar surface, an upwardly extending post carried on said base member and adjustably fixed with respect thereto, a dressing tool fixed on said post, a pair of spaced followers on said base member adapted to simultaneously contact said template edge whereby when said base is moved on said planar surface said tool effects a dressing operation on said edge face of said wheel, said supporting means being provided with a pair of spaced, removable abutments adjacent to the template and disposed, when both abutments are in position, to straddle said followers, one abutment being in contact with each follower when said tool is in dressing alignment with said wheel whereby to prevent movement of said followers along said template.

2. In a radius dresser of the type provided with fixed supporting means having a planar upper surface, above which a wheel to be dressed is rotatable in a vertical plane on a fixed axis, means for dressing the peripheral edge face of said wheel comprising a template fixed above said supporting means, said template having 4 an edge shaped to the contour to be reproduced on said wheel edge face, a base member in sliding contact with said planar surface, an upwardly extending post carried on said base member and adjustably fixed with respect thereto, a dressing tool fixed on said post, a pair of spaced followers on said base member adapted to simultaneously contact said template edge whereby when said base is moved on said planer surface said tool effects a dressing operation on said edge face of said wheel, said supporting means being provided with removable abutment means adjacent said template and disposed, when in position, to contact one of said followers when said tool is in the plane of said wheel, so as to prevent movement of said base in one direction along said template.

3. In a radius dresser of the type provided with fixed supporting means having a planar upper surface, and above which a wheel of any diameter to be dressed is rotatable in a vertical plane on a fixed axis, means for dressing the peripheral face of said wheel comprising a template fixed on said supporting means having an edge shaped to a contour to be reproduced on said wheel face, a base slidable on said planar surface, a dressing tool carried by said base, said base being provided with a pair of spaced projections adapted to be placed in contact with said template edge, whereby, when said base is moved with said projections maintained in contact with said template edge, said tool effects a dressing operation on said peripheral face of said Wheel, and means connecting said tool and base for relative movement therebetween so that said tool will dress said contour on wheels of different diameters while the dis tance between said axis and edge remain constant, said connecting means comprising gauge block engaging surfaces carried by said tool and base aligned for engagement upon said relative movement so that the distance between said surfaces may be accurately adjusted to compensate for wheels of different diameters.

4. In a radius dresser of the type provided with fixed supporting means having a planer upper surface, and above which a wheel to be dressed is rotatable in a vertical plane on a fixed axis, means for dressing the peripheral face of said wheel comprising a template fixed on said supporting means having an edge shaped to a contour to be reproduced on said wheel face, a base slidable on said planar surface, a dressing tool carried by said base, said base being provided with a; pair of spaced projections adapted to be placed in contact with said template edge, disengageable locking means for disengageably locking said projections against movement along said edge in at least one direction and unlocking said projections for movement along said edge, whereby, when said locking means is unlocked and said 1 base is moved with said projections maintained in contact with said template edge, said tool effects a dressing operation on said peripheral face of said wheel corresponding to said contour edge, and means for moving supporting means parallel to said axis while said locking means is locked for effecting a cylindrical dressing operation on the peripheral face of said wheel.

References Cited in the file of this patent UNITED STATES PATENTS 2,162,836 Candee June 20, 1939 2,222,392 Baerer Nov. 19, 1940 2,269,805 Arter Jan. 13, 1942 2,415,010 Hill Jan. 28, 1947 2,446,833 Johnson Aug. 10, 1948 2,539,941 Allen Jan. 30, 1951 2,554,530 Hosinski May 29, 1951