Title of Invention

A WORK REST BLADE ASSEMBLY FOR A CENTRELESS GRINDER

Abstract

A work rest blade assembly for a centreless grinder comprising a work rest blade (4) having plurality of perforations along the length and a slanted end resting on work piece (3) which is being grounded and located between driven grinding wheel (1) and driven regulating wheel (2) of a centreless grinder is provided. A fluid inlet (5) is provided on the said work rest blade (4) which is connected to a fluid feed pipe (7) to feed coolant fluid and a support (6) for mounting the said work set blade (4) between the driven grinding wheel (1) and driven regulating wheel (2) of a centreless grinder

Full Text

The invention relates to a work rest blade assembly for a centreless grinder. The work rest assembly according to the invention comprises a work rest blade with a slanted end mounted between the driven grinding wheel and driven regulating wheel of a centerless grinder. The slanted end of the work rest blade support the work piece which is being ground and is located between a driven grinding wheel and driven regulating wheel of a centerless grinder. Work rest blade assembly for a centreless grinder known in art provides multiple wear surfaces on which work piece is supported. Such work rest blade assembly comprises a generally cylindrical work rest bar splined at opposite ends and clamped to a crowned plate in such a manner that the bar is flexed from end to end to impose a bending moment thereon and is twisted in opposite directions at opposite ends so as to impose a rotary moment on the bar and thus rigidify. Reference for such work rest assembly may be made to U.S. Pat.No.4,069,613. The reference may also be made to U.S. Pat No.5,121,571 wherein the work piece support for centreless grinding comprises a rotable base mountable to a standard grinding machine and a carriage assembly mounted on the rotable base. The carriage assembly has a motor driven regulating roller attached thereto for driving the work piece. The work piece guides selectively attachable thereto comprises a pressure roller and a guide rest place with a work piece guide blade magnetically mounted thereon. The reference may also be made to U.S. Pat.No.6,083,084 wherein a cold gas stream supply device including a cooling gas nozzle through which a cold gas stream having a temperature lower than an ambient temperature of the machining apparatus is supplied to a machining point for cooling the machining point through the work holder which interposed between the regulating wheel and the grinding wheel and being located on one of the opposite sides of the work remote from the work blade. The main drawbacks of the work rest assembly for centreless grinder known in the prior art are as follows : 1. The finish of the final work piece deteriorate due to higher friction between the work piece and the work rest blade. 2. The power consumption during the grinding operation is high due to higher friction between work piece and work rest blade. The object of the invention is to provide a work rest blade assembly for a centreless grinder in which the friction between the work rest blade and the work piece is considerably reduced. Another object of the invention is to ensure uniform cooling during grinding and improve efficiency of grinding by reducing the power requirement and grinding time per unit volume of the work piece. Accordingly the present invention provides a work rest blade assembly for a centreless grinder comprising a work rest blade having plurality of perforations along the length and a slanted end resting on work piece which is being grounded and located between driven grinding wheel and driven regulating wheel of a centreless grinder, a fluid inlet being provided on the said work rest blade which is connected to a fluid feed pipe to feed coolant fluid and a support for mounting the said work set blade between the driven grinding wheel and driven regulating wheel of a centreless grinder. The work rest assembly for the centreless grinder according to the invention is described below with reference to the accompanying drawings. Figure 1 shows the work rest assembly according to the invention mounted between driven grinding wheel and driven regulating wheel of a centreless grinder. Figure 2 shows the side view of the work rest blade. Figure 3 shows the plan view of the work rest blade. The work rest assembly according to the invention comprises a work rest blade (4) with a slanted end in for resting work piece (3). The work rest blade (4) is provided with a fluid inlet (5) which is connected to a fluid pipe (7) through which coolant fluid is fed during grinding. The work rest blade (4) is provided with perforations (8) providing plurality of air passages along the length of the work rest blade. The coolant fluid may be gases such as air or oxygen or mixture of them having a temperature less than the ambient temperature. Alternately the coolant fluid may be liquid such as oil, water or an emulsion of water and oil. Work rest blade (4) may be made of metal, polymer or ceramic materials. The perforation (8) in the work rest blade (4) improves cooling of the work rest blade during grinding. The work rest blade (4) is provided with a support (6), which is mounted on the centreless grinder such that the work rest blade (4) is located between driven grinding wheel (1) and driven regulating wheel (2) of the centreless grinder. The work piece (3) rest at the tip of the work rest blade (4) during grinding. The work rest blade assembly according to the invention improves the grinding performance compared to the use of conventional work rest blade assembly as shown in the comparative study given below. Machine used is Centreless Grinder Wheel size : 400 mm x 200 mm x 203 mm Wheel Speed: 1550 rpm Wheel Grade : CUMI TDV 391 Control Wheel Size : 300 mm x 200 mm x 160 mm Feed: Through feed Width of work-rest blade:20 mm Depth of Cut: 0.3 mm Work Piece : Hardned steel WE CLAIM : 1. A work rest blade assembly for a centreless grinder comprising a work rest blade (4) having plurality of perforations along the length and a slanted end resting on work piece (3) which is being grounded and located between driven grinding wheel (1) and driven regulating wheel (2) of a centreless grinder, a fluid inlet (5) being provided on the said work rest blade (4) which is connected to a fluid feed pipe (7) to feed coolant fluid and a support (6) for mounting the said work set blade (4) between the driven grinding wheel (1) and driven regulating wheel (2) of a centreless grinder 2. A work rest blade assembly as claimed in claims 1, wherein the work rest blade (4) is made of metal. 3. A work rest blade assembly as claimed in claims 1, wherein the work rest blade (4) is made of polymer. 4. A work rest blade assembly as claimed in claims 1, wherein the work rest blade (4) is made of ceramic. A work rest blade assembly for a centreless grinder substantially as hereinabove described and illustrated with reference to the accompanying drawings.

Documents:

0041-che-2003-claims duplicate.pdf

0041-che-2003-claims original.pdf

0041-che-2003-description(complete) duplicate.pdf

0041-che-2003-description(complete) original.pdf

041-che-2003-abstract.pdf

041-che-2003-correspondnece-others.pdf

041-che-2003-correspondnece-po.pdf

041-che-2003-drawings.pdf

041-che-2003-form 1.pdf

041-che-2003-form 26.pdf

041-che-2003-form 3.pdf