US3161995A

US3161995A - Grinding wheel

Info

Publication number: US3161995A
Application number: US152219A
Authority: US
Inventors: Frederick W Lindblad
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-11-14
Filing date: 1961-11-14
Publication date: 1964-12-22
Anticipated expiration: 1981-12-22
Also published as: CH413639A; GB1009840A

Description

Dec. 22, 1964 w LINDBLAD 3,161,995

GRINDING WHEEL Filed Nov. 14. 1961 INVENTOR. FEoRcK W. LmoeLAo United States Parent Office &161395 Patented Dec. 272, 1964:

3,151,995 GRlNllNG WHEEL Fredericls W. Linrlhlad, 835 rllinois Ave., Aurora, ill. Filed Nov. 14, 19631, Ser. No. 152319 7 Claims. (Ch 51-209) This invention relates in general to grinding and, more particularly, to a grinding wheel wherein an abrasive member that performs the grinding operation is Secured to a body or core.

It is an object of the present invention to provide a grinding wheel which permits increased air cooling of the abrasive member and the interfaces between the abrasive member and the body or core upon which the abrasive member is mounted. r

lt is a further andmore specific object of the present invention to provide'a grinding wheel of the type stated in which the outer surface of the body or core has a plurality of air passageways which terminate at an interface between the abrasive member and body so that air moving along the passageways can cool the abrasive member and the interface between it and the body.

The attainment of the above and further objects of the present invention will be apparent from the following specification taken in conjnnction with the accompanying drawing forming a part thereof.

In the drawing:

FIG. l is a top plan view of a grinding wheel constructed in accordance with and einbodying the present invention;

FlG. 2 is a sectional View taken along line 2-2 of FlG 1;

FlG. 3 is a bottom plan View of the grinding wheel;

FIG. 4 is a fragmentary sectional View, on an enlarged scale, taken along line 4-4 of FG. 3; and

FlG. 5 is a fragmentary sectional view taken along line 5 5 of FIG. 4.

Reference may now be had to the drawing, which illustrates a preferred embodiment of the present invention, and wherein like reference characters designate like parts throughout.

l`he grinding wheel A comprises a core or body l which may be a ilared cup-shaped member which, inthe broad aspects of this invention, may be molded or otherwise formed of any desired material. Nylon has been found to be a suitable material out of which to fabricate the body l because of the fact that nylon imparts a small amount of resiliency to the body l. However, other materials may be used in the fabrication of the body 1, another preferred material being a phenolic molding compound, such as explained in rny United States Patent 2,703,437 that issued March 8, 1955. The body 1 may have any suitable shape, as, for example, the trusto-conical shape shown. At its smaller diameter end, the body i has a wall 3 which lies at rightangles to the central longitudinal axis a of the body and has a hole 5 for mounting the body upon the arbor of a grinding machine.

At its larger diameter end, the body l has a seat '7 which receives and supports a frusto-conical grinding ring 9. The seat 7 may comprise a shoulder 11 formed on the exterior surface of the body 1 and lying at right angles to the axis a. The seat 7 also includes a fusto-conical fiange 13 which extends from the shoulder 11 to the larger diameter end of the body l for receiving the internal frusto-conical surface of the grinding ring 9. The larger diameter end of the flange 13 has a plurality of circumferentially spaced notches 15 which extend toward the shoulder ll whereby the fiange 13 may be bent inwardly, that is, toward the central axis a to enable the grinding ring 9 to be slipped over the ilange 13 and seat against the shoulder 11.

The grinding ring 9 is molded to the shape shown and may be of any conventional type. One such type may be a ring having industrial diamond abrasive particles nolded within a body of plastic. When the grinding ring 9 has been fabricated, it is assembled with the body l with a bonding agent between the grincling ring 9 and the seat 7. Epoxy resins are bonding agents suitable for this purpose.

Formed on the outer frusto-conical surface 17 of the body I are circumferentially spaced slots 19 eachof which extend from the smaller diameter end of the body 1 to the shoulder ll. In the form of the invention shown, the body may be molded with the Slots 19 therein. It has been found that these Slots 19 form air passageways that increase the air cooling of the grinding ring 9 and the body 1, and particularly the interface between the two. The grinding wheel A is of a type which is intended to be operated at a very high speed of rotation. For eX- ample, the linear speed at the outer periphery of the grinding ring 9 may eXceed one mile per minute. At such high speeds, the rotating grinding wheel tends to drag with it a film of air which also moves at a high velocity but, of necessity, somewhat less than the velocity of the grindng wheel. It is believed that this rotating air layer creates a vacuum `at the surface 17 and in the slot 19 so that air may flow into the slots lil and against the portions of the grinding ring at the end of each slot 19. This movement of air in the slots 19 will cool both the grinding ring 9 and the interface between the grnding ring 9 and seat 7 wherein the bonding resin is located. Consequently, the provision of air passageways 19 on the surface of the body 1 helps to prevent a deterioration of the grinding ring 9 and the bonding agent at the interface between the grinding ring 9 and body i, thereby increasing the service life of the grinding wheel.

The inner frusto-conical surface 21 may, if desired, be provided with vanes 23 that act as fan blades and maintain a stream of air across the inner surface of the flange 13 and the portion of the inner frusto-conical surface of the grindng ring 9 that is exposed at the Slots 19. This further facilitates cooling the grinding ring 9 and its interface with the body l.

When the body 1 is molded in accordance with the process of my prior United States Patent 2,703,437, which is within the concept of the present invention, the ring 9 may be molded in place at the same time, all as disclosed in my above patent.

ln compliance with the requirernents of the patent statutes I have herein shown and described a preferred embodiment of the invention. lt is, however, to be under- I stood that the invention is not limited to the precse con-. struction herein shown, the same being merely illustrative of the principles of the invention. What is considered new and sought to be Secured by Letters Patent is:

l, A grinding wheel comprising a body having means for mounting same for rotation about the central longitudinal aXis of the body, means on said body forming a seat surrounding said aXis, and an abrasive member on said seat, the portion of the body that extends between the abrasive member and the means for mounting the body being substantially a surface of revolution centered on said axis but deviating from a surface of revolution by having means for directing a flow of cooling air against the abrasive member, said ilow directing means compris ing Channels in the surface of revolution and each channel extending to the juncture of the abrasive member with the body, and directing a flow of air toward said juncture for accentuating motion of cooling air at the region of said juncture. i

2. A grinding wheel comprising a hollow frusto-conical body havin means at'the smaller diameter end for i mounting the same for rotation about the central longtudinal axis of the body, the larger diameter end of the body having a radially extendng seat for a grinding ring, said seat comprising an annular shoulder forrned on the outer surface of the body and facing in the direction toward the larger diameter end of the body, said shoulder lying at right angles to the axis of rotation of the body, and a hollow frusto-conical grinding ring the smaller diameter end of which rests on said seat and said ring fiaring radially outwardly from said seat toward its larger diameter end, the body having a part thereto that extends from the shoulder to the larger diameter end of said body and said part receiving the inner surface of the grinding ring and supporting said grinding ring over a major portion of its axial length, the outer surface of the body having a plurality of circumferentially spaced grooves each extending radially outwardly to and terminating at the shoulder.

3. A grinding wheel comprising a hollow frusto conical supporting body having means at the smaller diameter end for mounting the same for rotation about the central longitudinal aXis of the body, the larger diameter end of the body having a radi ally extending seat for a grinding ring, said seat comprising an annular shoulder formed on the outer surface of the supporting body, said shoulder extending from the exterior of the body towards the interier thereof, and a hollow frusto conical grinding ring the small diameter of which rests on said seat and said ring fiaring radially outwardly from said seat towards its larger diameter end and said ring being backed at its inner frusto conical surface to a major portion of the axial length of its frusto conical surface by the part of the supporting body that extends from the seat to the larger diameter end of the body, said ring being of abradable material terminating wat its larger diameter end in a grinding surface, the ring being of substantially smaller mass than the mass of the supporting body, and the portion of the supporting body between the seat and the outermost larger diameter end thereof being of plastic material that may be progressively dressed away as the grinding surface of the grinding ring is progressively worn whereby the edge of the supporting body at the larger diameter end thereof may be maintained in reinforcing position immediately adjacent to the grinding surface thereof during the progressive wearing away of the ring, said body having formed in its outer surface a plurality of circumferentially spaced grooves that extend from said smaller diameter end and terminate at said shoulder and being effective by rotation of the body for accentuating a movement of cooling air against said seat.

4. A grinding wheel comprising a hollow frusto conical supporting body having means at the smaller diameter end for mounting the same for rotation about the central longitudinal axis of the body, the larger diameter end of the body having a radially extending seat for a grinding ring, said seat comprising an annular shoulder formed on the outer surface of the supporting body and extending from the exterior of the body towards the inten'or thereof, and a holiow frusto conical grinding ring the smaller diameter of which rests on said seat and said ring flaring radially outwardly from said seat towards its larger diameter end and said ring being backed at its frusto conical surface to a major portion of the axial length of its frusto conical surface by the part of the supporting body that extends from the seat to the larger diameter end of the body, said ring terminating at its larger diameter end in a grinding surface, the ring being of substantially smaller mass than the mass of the supporting body, and the portion of the supporting body between the seat and the outermost larger diameter end thereof being of plastic material that may be progressiyely dressed away as the grindirg surface of the gn'nding ring is progres:

sively worn whereby the edge of the supporting body at the larger diameter end thereof may be maintained in reinforcing position immediately adjacent to the grinding surface thereof during the rogressive wearing away of the ring, said body having a plurality of grooves in its outer surface that extend from the seat toward said smaller diameter end of the body for accentuating a movement of cooling air against said seat.

5. A grinding wheel comprising a hollow frusto conical body having means at the smaller diameter end for mounting the same, a frusto conical grinding ring located on the outer surface of said body at the larger diameter end thereof and backed'at its inner surface by the frusto conical surface of the body over a major portion thereof, and cooling means on the outer surface of said body for accentuating a movement along the outer frusto conical surface of the grinding ring, said cooling means including Channels in said outer surface that terminate at the juneture of the grinding ring and body.

6. An abrasive grinding wheel comprising a hollow frusto-conical body having means at its smaller diameter end for mounting the same, a grinding ring seat formed at the outer circtunference of the larger diameter end of the body, and a frusto conical grinding ring resting on said seat and reenforced by being backed at its inner frusto conical surface'by said body to a major extent of the outer frusto conical surface of said ring, said ring including a diamond ab rasive and said body belin of plastic so that as the ring is progressively worn away the body may be progressively dressed away while maintaining its reenforcement around the ring up to the region of the abrading working surface of the ring, the portion of the body that extends between the abrasive member and the means for mounting the body being substantially a surface of revolution centered on the wheel axis but deviating from a surface of revolution by having means forming radially out- Wardly opening Channels along the surface and each channel extending to the juncture of the abrasive member with the body for accentu ating motion of cooling air along the outside of the frusto conical body towards the radially outermost edge of the outer frusto conical surface of the grinding ring.

7. A grinding wheel comprising a hollow body having means at one end thereof for mounting the body for rotation about the central longitudinal axis of the body, said body also having an outer frusto conical surface surrounding said aXis and terminating at its larger diameter end at the other end of the body, said surface terminating at its smaller diameter end in an annular shoulder concentric with said axis, and `a frusto conical grinding ring the small diameter of which rests on said shoulder, the inner frusto conical surface of said ring being backed by the part of the body having the frusto conical surface and said part of the body extending over a major portion of the inner frusto conical surfacetof the ring to reinforce the ring up to the region of the working surface thereof, said frusto conical body surface having a plurality of circumferentially spaced radially outwardly opening grooves that terminate at said shoulder for accentuating the motion of cooling air along said frusto conical body surface toward said shoulder.

References Cted in the file of this patent UNITED STATES PATENTS Tone Ian. 10, 1939 Whting L Jan. 5, 1943 Lindblad June 28, 1960 i FOREIGN PATENTS Canada u Sept. 11, 1956

Claims

1. A GRINDING WHEEL COMPRISING A BODY HAVING MEANS FOR MOUNTING SAME FOR ROTATION ABOUT THE CENTRAL LONGITUDINAL AXIS OF THE BODY, MEANS ON SAID BODY FORMING A SEAT SURROUNDING SAID AXIS, AND AN ABRASIVE MEMBER ON SAID SEAT, THE PORTION OF THE BODY THAT EXTENDS BETWEEN THE ABRASIVE MEMBER AND THE MEANS FOR MOUNTING THE BODY BEING SUBSTANTIALLY A SURFACE OF REVOLUTION CENTERED ON SAID AXIS BUT DEVIATING FROM A SURFACE OF REVOLUTION BY HAVING MEANS FOR DIRECTING A FLOW OF COOLING AIR AGAINST THE ABRASIVE MEMBER, SAID FLOW DIRECTING MEANS COMPRISING CHANNELS IN THE SURFACE OF REVOLUTION AND EACH CHANNEL EXTENDING TO THE JUNCTURE OF THE ABRASIVE MEMBER WITH THE BODY, AND DIRECTING A FLOW OF AIR TOWARD SAID JUNCTURE FOR ACCENTUATING MOTION OF COOLING AIR AT THE REGION OF SAID JUNCTURE.