US2942387A

US2942387A - Cup-shaped diamond grinding wheel

Info

Publication number: US2942387A
Application number: US718736A
Authority: US
Inventors: Frederick W Lindblad
Original assignee: Individual
Current assignee: Individual
Priority date: 1958-03-03
Filing date: 1958-03-03
Publication date: 1960-06-28
Anticipated expiration: 1977-06-28

Description

June 28, 1960 w. |NDB| AD 2,942,387

CUP-SHAPED DIAMOND GRINDING WHEEL Filed March 3, 1958 INVENTOR l4 azozmck w. Lmoauo {33; I W I (3 V 7 ATTY.

States Patented June 28, 1960 Frederick W. Lindblad, Chicago, III. (835 Illinois A've., Aurora, Ill.)

Filed Mar. 3, 1958, Ser. No. 718,736

Claims. (Cl. 51209) This invention relates to abrasive grinding wheels, par- .ticularly such grinding wheels as utilize diamond abrasive material. It is especially concerned with grinding wheels of the flared cup type, that is one wherein an abrading section is combined witha body section that is of the shape of a flared cup.

It is one of the objects of the present invention to provide an abrading wheelof the above mentioned type which can be fabricated by combining a one piece prefabricated abrading section with a one piece prefabricated body section.

It is another object of the present invention to provide a flared cup type'of abrading wheel wherein the grinding section and the core section may each be prefabricated separately and then combined to form a finished wheel.

In a flared cup type grinding wheel wherein the ring of grinding material is on the outside of the cup there are certain disadvantages insofar as concerns the holding of the grinding ring on the core. It is an object of the present invention to overcome many of these objections by locating the diamond ring on the inner side of the cup shaped core and thereby utilizingthe sloping walls of the core to help hold the diamond ring in place, and

wherein the bond between the diamond core and the ring is under compression when the Wheel is in use rather than under tension, thereby producing a better holding action.

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

Fig. 1 is a top plan view of the abrading'wheel embodying the present invention;

Fig. 2 is a side view of the wheel of Figure 1, in quarter.

section; a

Fig. 3 is a plan view illustrating modified construbtion; and

Fig. 4 is a sectional view taken along 44 of Fig. 3. Reference may now be had more particularly to the. drawing wherein like reference numerals designate like parts throughout. 7

The wheel A of Figures 1 and 2 consists of a body or core 1 of a generally frusto-conical shape having a diamond abrasive ring 2 imbedded therein. The body or core 1 has the usual opening 3 for mounting the same upon the arbor of a machine. The edge 4 of the grinding ring 2 is the working edge. The body 1 is a preformed flared cup shape body that may be moulded of any desired material, preferably plastic material, but

not limited to plastic material. A preferred plastic composition is of nylon which imparts a desired small amount of resiliency to the core. Other suitable plastics that may also impart a limited amount of resiliency to the core are tenite, etc.

2 8 terminates in a thin surface 10 that is concentric with the outer frusto-conical surface of the core and which leaves a thin section 12 of core material at an obtuse angle to the shoulder 8. The inner surface 10 may be' machined to the desired dimension if the dimension of the flared cup as moulded is not precisely accurate.

The abrasive ring 2 is moulded to the shape shown and consists of industrial diamond abrasive particles moulded within a body of plastic. The composition of the diamond abrading ring 2 including the diamond particles and the plastic filler may be any preferred conventional type, for instance as described in my United States Patent 2,703,437, issued March 8, 1955. When the abrasive ring 2 has been fabricated and the core 1 has been fabricated the two are assembled as shown, with a suitable bonding agent or cement between them. The bonding face between the diamond sectionand the core, and thatto check measure the diamond section before assembly with thecore since the diamond section is preformed accurately to shape before it is assembled with the preformed core. It is easier to dress this type of wheel, and in addition there is a visual guide to help the operator determine when to redress the core away from the outside edge thereof. The highly objectionable consequences of failure to dress the core are therefore minimized. The support for the diamond section is along the entire interentire interface is in compression when grinding pressure is applied to or by the grinding ring 2. This better support gives longer life to thewheel. The core material may be of the type which will soften and be pushed away if the pressure is great enough. As a result there is no The core 1 has a radially'extending seat for the ring 2,

danger of abusing the wheel even if the core material is not dressed away.

Figures 3 and 4 show a grinding wheel 14 similar to that of Figures 1 and 2 but dilfering therefrom in that the inner. surface of the flared cup shaped core is provided with vanes 15 that act as fan blades and maintain a stream of air in movement across the inner face of the abrasive ring 2 thus facilitating cooling of that ring If desired, water cooling may be used, in which event the vanes move the water outwardly towards and across the inner surface of the abrasive ring 2. V

In compliance with requirements of the patent statutes I have herein shown and described a preferred embodiment'of the present invention. It is, however, to be understood that the invention is not limited to the construction herein shown, the same being merely illustrative of the principlesof the invention. What is considered new and to be covered by Letters Patentis;

l. A grinding wheel comprising a hollow frusto conicalsupporting 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 inner surface of the supporting body and facing in the direction towards the larger diameter end of the body and said shoulder extending from the'interior of the body towards the exterior thereof and at right angles to the longitudinal axis of the body, anda" t. hollowfrusto conical grinding ring the small 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 surrounded and backed at its frusto conical surface to a major portion of the axial length of its frusto conical surface by the part of the supportingbodythat'extends from the seat to'the larger diameter end'of :the body, said ring being of abradablermaterial teiminating at its larger diameter end in a grinding surface that is substantially parallel to said grinding ring seat onthe said body thering being of substantially smaller mass thanithe 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 around the ring immediately adjacent to the grinding surface thereof during the progressive wearing away of the ring.

2. A grinding wheel comprising a hollow frusto conical supporting body having means at the smaller diametcrend 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 fora grinding ring, said seat comprising an annular shoulder fonned on the inner surface of the supporting body and facing in the direction towards the larger diameter end of the body and extending from the interior of the body towards the exterior thereof and making an obtuse angle with the frusto-conical portion of the inner surface'ofthe body that extends from the shoulder towards the larger diameter-end of the body, and a hollow 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 surrounded and backed at its frusto conical surface -to a major portion of the axial length of its frustoconical 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 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 around the ring immediately adjacent to the grinding surface thereof during the progressive wearing away of the ring.

3. A grinding wheel such as defined in claim 1 having fluid circulating vanes on the inner surface of the frusto conical supporting body for maintaining flow of cooling fluid within the body in movement radially outwardly and over the inner frusto-conical surface of the abrading ring.

4. A grinding wheel such as defined in claim 2 having fluid circulating vanes on the inner surface of the frusto conical supporting body for maintaining a flow of cooling fluid within the body in movement radially outwardly and over the inner frusto-conical surface of the abrading ring.

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 inner surface of said body at the larger diameter end thereof and backed by the frusto conical surface of the body over a major portion thereof, and cooling vanes on the inner surface of said body for maintaining a flow of cooling fluid radially outwardly and over the frusto-conical surface of the grinding ring. 7

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 inner circumference 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 outer frusto-conical surface by said body to a major extent of the outer frusto-conical surface of said ring.

7.'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 inner circumference-of the larger diametenend of the body, and a frusto conical grinding ring resting on said seat and reenforced by being backed at its outer frusto-conical surface by said body to a major extent of the outer frusto-conical surface of said ring, said ring including a diamond abrasive and said body being 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.

8. A grinding wheel of the type comprising a grinding ring of comparatively expensive material and a supporting body therefor of material that is inexpensive in com-' parison with the material of the'grinding wheel, said supporting body being of frusto conical shape adapted to be mounted for rotation about the central longitudinal axis of the frusto cone, the larger diameter end of the frusto cone having a radially extending seat for a grinding ring; said seat comprising an annular shoulder formed on the inner surface of the supporting body and facing in the direction towards the larger diameter end of the body and extending fromthe interior of the frusto cone towards the exterior thereof, and a hollow frusto conical grinding ring the smaller diameter end of which rests on said seat and said'ring flaring radially outwardly from said seat towards the larger diameter end of the ring and the ring being surrounded and backed at its frusto-conical surface over a major portion thereof by the part of the supporting body that extends from the seat to the larger diameter end thereof, the'ring being of substantially smaller mass that the mass of the supporting body.

9. A grinding wheel comprising a hollow frusto-conical body having means at the smaller diameter for mounting same, a frusto-conical grinding ring of abradable material and being located on the inner surface of said body at the larger diameter end thereof, said ring being backed by the frusto-conical surface of the body over a major portion of the frusto-conical surface of the ring, the frusto-conical body being of a plastic material that may be progressively dressed away as the grinding surface of the ring is progressively worn, and cooling vanes on the inner surface of said body for maintaining a flow of cooling fluid radially outwardly and over the frusto-conical surface of the grinding ring.

10. A grinding wheel comprising a hollow body having the outer 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 outer frusto-conical surface of the ring to reinforce the ring up to the region of the working surface thereof.

References Cited in the file of this patent UNITED STATES PATENTS 2,307,312 Whiting Ian. 5, 1943 2,320,130 Harris May 25, 1943 2,806,331 Hoye Sept. 17, 1957