Field of the Invention:
The present invention generally relates to maintenance of grinding wheels used for abrasive machining. More particularly, the present invention relates to a roll form wheel dresser used for knocking worn-out abrasive particles of a grinding wheel while still maintaining concentricity of the grinding wheel.
Background of the Invention:
A grinding wheel is an expendable wheel made from a matrix of coarse, abrasive particles pressed and bonded together to form a solid, circular shape. Each of the coarse, abrasive particles of the grinding wheel acts as a cutting tool for facilitating abrasive machining. More specifically, sharp cutting edges of each of the coarse, abrasive particles on grinding wheel's surface remove small chips from a work-piece via shear deformation. In order to achieve effective grinding and satisfactory finish on the work-piece, proper selection of the grinding wheel is of primary importance. The small cutting edges of the coarse, abrasive particles on grinding wheel's surface become dull with regular use of the grinding wheel. In order to achieve a free cut and produce a satisfactory finish on the work-piece, a layer of coarse, abrasive particles with the sharp cutting edges is required to be maintained on the surface of the grinding wheel. For maintaining a layer of coarse, abrasive particles with the sharp cutting edges on the surface of the grinding wheel, dressing of the grinding wheel is required.
Wheel dressing is the process of knocking worn out abrasive particles with dull cutting edges from the grinding wheel's surface and exposing fresh abrasive particles with sharp cutting edges on the grinding wheel's surface,
while still maintaining the concentricity of the grinding wheel. The wheel dresser includes hard cutting points that fractures the worn out abrasive particles on the grinding wheel's surface for re-sharpening of the cutting edges of the worn out abrasive particles or completely removes the worn out abrasive particles for exposing fresh abrasive particles that has sharp cutting edges. The wheel dresser further cleans out tiny spaces between the abrasive particles, thereby removing metallic dust and other particles which eventually clog up pores of the wheel face and adversely effects performance of the grinding wheel.
Apart from proper selection of the correct grinding wheel, selection of the proper truing or dressing tool and proper use thereof is also important. More specifically, incorrect dressing causes a satisfactory grinding wheel to act unsatisfactorily. On the other hand use of a good dressing tool can improve life and grinding action of the grinding wheel.
The wheel dresser includes a plurality of hard cutting points disposed on a surface there-of, the hard cutting points of the wheel dresser rub against the grinding wheel to cause dressing of the grinding wheel. The hard cutting points of the wheel dresser functions like cutting tool and like all cutting tools the hard cutting points of the wheel dresser gets dull with regular use of the wheel dresser. The wheel dresser, particularly, the roll form wheel dresser has a cylindrical body provided with a cavity extending around a periphery thereof. The cavity is having a contour such that the cavity receives a peripheral portion of a grinding wheel of a particular size. As the roll type wheel dresser rotates about an axis of rotation, the cutting points disposed on the curved profile of the cavity rub against the peripheral
portion of the grinding wheel to cause dressing of the grinding wheel. Although, the wheel dresser disclosed herein is used for dressing the grinding wheel used in the machining of outer track-surface of the bearings, the wheel dresser of the present invention may be used for dressing of grinding wheels used in other applications.
The wheel dresser is required to be appropriately positioned with respect to the grinding wheel being dressed by the wheel dresser for achieving high-grade dressing of the grinding wheel. In accordance with the prior art arrangements for locating the wheel dresser with respect to the grinding wheel, the work-piece and the grinding wheel performing abrasive machining on the work-piece are centrally aligned with respect to each other, whereas top edge of the grinding wheel is considered as a reference for positioning the wheel dresser with respect to the grinding wheel. However, considering the top edge of the grinding wheel as reference for positioning the wheel dresser with respect to the grinding wheel requires lot of time for setting the position of the wheel dresser with respect to the grinding wheel. Considering top edge of the grinding wheel as a reference for positioning the wheel dresser with respect to the grinding wheel leads to inaccurate dressing of the grinding wheel. Inaccurate dressing of the grinding wheel causes inefficient operation of the grinding wheel.
Due to inaccurate dressing of the grinding wheel, the grinding wheel may get permanently damaged and the grinding action thereof may be adversely affected, which in turn may damage the work-piece. Furthermore, if the wheel dresser is not properly placed relative to the grinding wheel, the wheel dresser may also get damaged. The in-appropriate placement of the wheel
dresser with respect to the grinding wheel may damage the grinding wheel and the wheel dresser and render the work-pieces machined by the grinding wheel defective.
Accordingly, there is a need for maintaining a large inventory of the wheel dressers and grinding wheels, depending on width of the object and Portion of contour with respect to reference face. Costs associated with maintaining such large inventories of wheel dressers and grinding wheels are also high. There is felt a need to accurately position the wheel dresser with respect to the grinding wheel for preventing damage to the wheel dresser and the grinding wheel, thereby reducing the consumption of the grinding wheels and accordingly reducing the inventory of wheel dressers and grinding wheels. There is a need for reducing part change time & cost associated to it for grinding wheels of Different type/size of bearings. Further, there is a need to reduce consumption of grinding wheels by elimination of initial truing amount.
Objects of the Invention:
The principle objective of the present invention is to provide an arrangement for accurately placing a roll form dressing tool with respect to a top edge of a grinding wheel for precision dressing of the grinding wheel.
Another object of the present invention is an arrangement for accurately placing a roll form dressing tool with respect to a grinding wheel that reduces grinding wheel inventory and consumption.
Another object of the present invention is to provide an arrangement for facilitating quick setting of position of a roll form dressing tool with respect to a grinding wheel.
Still another object of the present invention is to provide an arrangement for placing a roll form dressing tool relative to a grinding wheel that enhances life of the grinding wheel.
Yet another object of the present invention is to provide an arrangement for placing a roll form dressing tool relative to a grinding wheel that reduces inventory of the grinding wheel.
Another object of the present invention is to provide an arrangement for placing a roll form dressing tool relative to a grinding wheel that reduces consumption of the grinding wheel.
Still another objective of the present invention is to provide an arrangement for placing a roll form dressing tool relative to a grinding wheel that maintains grinding wheels in proper working conditions.
Brief Description of the Accompanying Drawings:
The invention will now be explained in relation to the accompanying drawing, in which:
Figure 1 illustrates a prior art arrangement for placing a roll form dressing tool with respect to a grinding wheel, wherein top edge of the grinding wheel is considered as a reference for positioning the roll form dressing tool
and the dressing tool is designed by considering the center of cavity to be ground as a reference; and
Figure 2 illustrates an arrangement for accurately placing a roll form dressing tool with respect to a grinding wheel in accordance with an embodiment of the present invention, wherein, the dressing tool is designed by considering a top edge of the cavity to be ground as a reference.
Detailed Description:
The invention will now be described with reference to the accompanying drawings which do not limit the scope and ambit of the invention. The description provided is purely by way of example and illustration.
Referring to Figure 1 of the accompanying drawings, a prior art arrangement 10 for placing a roll form dressing tool 02 with respect to a grinding wheel 04 is illustrated, wherein top edge of the grinding wheel 04 is considered as a reference for positioning the roll form dressing tool 02. In accordance with the prior art arrangement 10, the work-piece 06 and the grinding wheel 04 performing abrasive machining on the work-piece 06 are centrally aligned with respect to each other, whereas top edge of the grinding wheel 04 is considered as a reference for positioning the wheel dresser 02 with respect to the grinding wheel 04. However, considering the top edge of the grinding wheel 04 as reference for positioning the wheel dresser 02 with respect to the grinding wheel 04 requires lot of time for setting the position of the wheel dresser 02 with respect to the grinding wheel 04. Further, the prior art arrangement 10 for positioning the roll form dressing tool 02 with
respect to the grinding wheel 04 for dressing the grinding wheel 04 fails to maintain concentricity of the grinding wheel 04. Different Size of GW requires for different range of products. Further, the dressing tool 02 is designed by considering the center of cavity to be ground as a reference point. More specifically, point "A" is a reference point for designing of the dressing tool 02.
Referring to Figure 2 of the accompanying drawings, an arrangement 20 for accurately placing a roll form dressing tool/ roll type wheel dresser 12 with respect to a grinding wheel 14 in accordance with an embodiment of the present invention is illustrated, wherein center of the grinding wheel 14 is considered as a reference for positioning the roll form dressing tool 12. In accordance with the arrangement 20, the work-piece 16, the grinding wheel 14 performing abrasive machining on the work-piece 16 and the roll form dressing tool 12 are all centrally aligned with respect to each other. Centrally aligning the roll form dressing tool 12 with respect to the grinding wheel 14 is convenient, accurate and requires less time for setting the position of the roll form dressing tool 12 with respect to the grinding wheel 14. The roll form wheel dressing tool 12 has a cylindrical body provided with a cavity 12a extending around a periphery thereof. The cavity is designed with reference of top edge of the grinding wheel 12a is capable of receiving a peripheral portion of the grinding wheel 14. As the roll type wheel dresser 12 rotates about an axis of rotation 18 thereof, the cutting points disposed on the curved profile of the cavity 12a rub against the peripheral portion of the grinding wheel 14 to cause dressing of the grinding wheel 14. The axis of rotation 18 of the roll type wheel dresser 12 is parallel to the axis of rotation of the work-piece 16 and the grinding wheel 14.
Centrally aligning the roll form dressing tool 12 with respect to the grinding wheel 14 reduces the chances of misalignment between the roll form dressing tool 12 and the grinding wheel 14, thereby leading to accurate dressing of the grinding wheel 14 and subsequently enhancing life of the grinding wheel 14 and quality of the surface finish of the work-piece 16. Further, the dressing tool 12 is designed by considering a top edge of the cavity to be ground as a reference. More specifically, "B" is a reference for designing of the dressing tool 12.
Technical Advantages and economic significance:
In accordance with an embodiment of the present invention there is provided an arrangement for accurately placing a roll form dressing tool with respect to a grinding wheel for precision dressing of the grinding wheel. The arrangement for accurately placing a roll form dressing tool with respect to a grinding wheel facilitates quick setting of position of the roll form dressing tool with respect to the grinding wheel. Further, the arrangement for placing a roll form dressing tool relative to a grinding wheel enhances life of the grinding wheel. Furthermore, the arrangement for placing a roll form dressing tool relative to a grinding wheel reduces consumption of the grinding wheel and accordingly reduces cost of the grinding wheel and consumption per piece of grinding wheel Furthermore, same grinding wheel can be used for a range of jobs to be ground, thereby reduces requirement of different sized grinding wheels and inventory of grinding wheels.
While considerable emphasis has been placed herein on the particular features of this invention, it will be appreciated that various modifications
can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the invention. These and other modifications in the nature of the invention or the preferred embodiments will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.