FIELD OF THE INVENTION
The invention relates to a method device for and a method of dressing grinding wheels to allow tools and other instrumentalities to be shaped, dressed, or formed thereby or therewith. In particular, this invention is concerned with obtaining great accuracy in dressing grinding wheels in which the face of the wheel is to be given a linear contour, along with a method and apparatus that is simple, economical, foolproof and inherently free from tendency to err or fall out of adjustment.
BACKGROUND OF THE INVENTION
Prior to this invention, the art of dressing grinding wheels has been attended with elaborate mechanisms and costly methods of forming the working contour of the wheel to correspond to the desired or intended linearity in shape on its peripheral or working face. Moreover, the prior art left much to be desired in speed of operation, ease of re-dressing, accuracy of dressing and re-dressing, and general simplicity of means and economy of operation. Heretofore when a grinding wheel became worn, dull or out of shape, or if for any other reason it was desired to redress it, for example to be able to generate intricate surface profiles or to resharpen machine tools such as of lathe machine or for any other reason, it has always been necessary to remove it from the machine in which it operates and place it in another machine adapted to dress the wheel. After being dressed it was then

necessary to transfer it back to the machine in which it was to operate. It was found that due to slight inaccuracies or nonconformities, of the spindles of the machine a grinding wheel which had been redressed and returned to the machine in which it was to operate was practically never exactly true to shape or position and required a considerable period of running with consequent waste of time and material of the grinding wheel before it was ready to be put back in operation for useful purposes. The present invention provides a method whereby precise wheel dressing, through selective triturating can be performed with little effort and in a minimum amount of time.
Within the objects of this invention, it is sought to cure the defects existing in the art as mentioned in part above, and to provide a method and means of dressing grinding wheels having low initial cost and unkeep, great and continuing accuracy inherent in its design and operation, ruggedness and simplicity in its construction and operation, all to the ultimate end of faithfully and consistently reproducing in and through the dressing of a grinding wheel.
OBJECTS OF THE INVENTION
It is, therefore, an object of the present invention to propose a device and a method by which a grinding wheel can be dressed or profiled without removing it from the dressing machine in which it operates, thus avoiding the work and loss of time

involved in transferring it to and from the dressing machine, and the running time required before the wheel is again properly centered ready for useful operation.
Another object of the invention to propose a wheel dressing mechanism, together with a device for urging said dressing tool under pressure against the peripheral face of the grinding wheel, while said wheel and dressing tool are relatively rotated, thereby linearly contouring the relatively soft peripheral face of the grinding wheel, so that in the operation of the latter, the desired linearity in profile is accurately reproduced upon the grinding wheel.
Yet another object of the invention to provide a mechanism of this kind in which the application of the pressure force of said dressing tool against the face of the grinding wheel is independent of the manual force or dexterity of the operator so that the reduction of grinding wheel diameter is held to a minimum and uniformly accurate results are produced.
A further object of the invention is to propose a wheel dressing mechanism, wherein the device for wheel dressing have minimum number of structurally durable parts cooperatively assembled in a compact manner, in which several adjusting means for the wheel dressing tool are easily accessible for operation.

SUMMARY OF THE INVENTION
In a first aspect of the invention, there is provided a device for dressing grinding wheels, comprising: a base plate 11 having a slot 12 towards its center to act as a rigid base to entire wheel dressing tool; a plate 21 T-welded upon the base plate 11 and having holes 23, 22; a plurality of inwardly placed L-shaped plates 31, 31’ abutting longitudinally with the Plate 21 such that holes 34, 34’ in the L-plates 31, 31’ match said holes 23, 22 in the Plate 21; a plurality of plain bearings 32, 32’ in L-plates 31, 31’ for supporting rotating ends 43, 43’ of a screw member 41, and a plurality of plain bearings 36, 36’ placed in hole 35, 35’ for supporting a strengthening rod 71; the screw member 41 effecting axial movement of a housing member 61 of the dressing tool relative to the screw member 41; the housing member 61 having bore 66 within which the dressing tool 81 is detachably held by means of another screw that uses a bore 62 provided at the top of the housing (61); an extended arm 44 of the screw member 41, beyond said plain bearing members 32’, threadedly supporting a rotary handle 51 through a threaded connection 45; and a handle 51 is expandable at its rotating end to form a gripping head 52;
In a second aspect of the invention, there is provided a method of dressing grinding wheel in a device as claimed in claim 1, said method comprising the steps of; assembling a left hand L-plate 31 on a plate 21 through holes 23 and 34 and pressing plain bearings 32 and 36 on the L-plate 31; pressing a rotating end 43 of a

screw 41 into the plain bearings 32 such that a collar face 46 of the screw 41 abuts the L-plate 31; mounting a dressing tool housing 61 rotatably and threadedly on the screw 41 to form a screw kinematic pair with the screw member 41; passing distal end 72 of a strengthening rod 71 through a hole 64 of the housing member 61 in order to be received in said plain bearings 36; fixing free ends 43’ and 72’ in the plain bearings members 32’ and 36’ respectively for completely supporting said screw member 41 and strengthening rod member 71; tightening the screw member (41) in bore 62 to fix a dressing tool 81 in the desired position; sliding the dressing tool 81 to a position which allows a forward end 82 or inturn a tool tip 83 of the dressing tool to be in close proximity with relation to the peripheral surface of the grinding wheel to be dressed; urging the housing member 61 on the screw 41 axially towards or away from the plate 31 using a handle grip head 52; moving the tool tip 83 of a dressing machine in a back and forth manner or side to side motion using screw 41 till the time sufficient particles have been stripped so that the grinding wheel is considered dressed; and withdrawing the dressing machine from the grinding wheel worktable.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
The foregoing and other features of the invention, comprising the improved wheel dressing mechanism together with the construction and relative arrangement of the

several parts, will be apparent from the following more particular description of the invention, as illustrated in the accompanying drawings, in which like reference characters refer to the same parts throughout the different figures and subsequently incorporated in the subjoined claims. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
Fig. 1 is line representation of proposed front view of developed device for grinding wheel dressing.
Fig. 2 is line representation of proposed top view of developed device for grinding wheel dressing
Fig. 3 is line representation of proposed side view of developed device for grinding wheel dressing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION
Before describing in detail, method and device of dressing grinding wheels in accordance with the present invention, it should be observed that the present invention resides primarily in a novel and non-obvious combination of hardware elements and method steps. Accordingly, these elements and steps have been represented by conventional elements and steps in the drawings, showing only those specific details that are pertinent to the present invention so as not to obscure the

disclosure with details that will be readily apparent to those skilled in the art having the benefit of the description herein.
The present invention is directed to solve the above-described problems of the prior art and to provide a method and means of dressing grinding wheels in accordance with the present invention and to enable to accurately dress slot wedges easily and in short time.
In present invention, the grinding wheel is a standard grinding or lapping wheel, that is to say, a wheel which contains or is impregnated with hard particles in working portion, mounted on a shaft which in operation is driven by an electric motor or the like.
Referring now to figure 1-3 in detail, the base plate 11 acts as the base of the complete fixture F wherein this base plate 11 comprises of a slot 12 towards its center. In general, the arm provided on the grinding wheel, to rest the workpiece while grinding is being worked upon it, comprises of a slot to fix an additional attachment in order to machine the job at an angle or any other customized setting depending on the angle as well as criticality of machining. Therefore, slot 12 on base plate 11 can be matched and bolted together to provide rigid base to entire wheel dressing tool. Plate 21 is T-welded upon base plate 11. Plate 21 is positioned and oriented in a way to provide greater base to L-plates 31, 31’ that are provided

structural support and rigidity to entire wheel dressing mechanism in accordance with present invention.
Plurality of L-shaped plates are constructionally managed as L-plates 31, 31’ on left and right side of the base plate 11 as shown in front view of the device through figure 1. L-plates 31, 31’ are inwardly placed with their legs facing each other and abutting longitudinally with Plate 21 and in a way that hole 34, 34’ in L-plates 31, 31’ matches hole 23, 22 in Plate 21.
As shown in figure 2 in detail, L-plates 31, 31’ are also provided with respective plurality of plain bearings 32, 32’ placed in hole 33, 33’. These plain bearings 32, 32’ are the mechanical elements used to reduce friction between rotating ends 43, 43’ of screw 41 and stationary support member L-plate 31, 31’. As shown in figure 2 in detail, L-plates 31, 31’ are also provided with respective plurality of plain bearings 36, 36’ placed in hole 35, 35’. The purpose of providing these plain bearings 36, 36’ is to provide a strengthened fixing point where strengthening rod 71 can be fixedly held and supported, through its longitudinal end 72, 72’ attached to stationary support member L-plate 31, 31’.
Constructionally, after assembly of left hand L-plate 31 on plate 21 through holes 23 and 34 and pressing of plain bearings 32 and 36 on L-plate 31, rotating end 43 of screw 41 is pressed into plain bearings 32 such that collar face 46 of screw 41 abuts

L-plate 31. The plain bearings 32 is primarily intended, in use, to receive the said screw member 41 for effecting axial movement of the dressing tool housing member 61 relative to the screw member 41. With distal end 43 supported on plain bearings 32, dressing tool housing 61 is rotatably received and threadedly mounted on screw 41 to form a screw kinematic pair as the internal circumference of the dressing tool housing member 61, through a standard box nut thread in hole 63 (not shown in figure), and the outer circumference of the screw member 41 each comprise a continuous thread. This housing member 61 also has a bore 66 within which the dressing tool 81 is detachably held by means of another screw that uses bore 62 provided at the top of the housing.
Also, distal end 72 of strengthening rod 71 is manually made to pass through through-hole 64 of the dressing tool housing member 61 in order to be received in plain bearings 36. Free end 43’ through abutting collar face 46’ and 72’ are now received by plain bearings members 32’ and 36’ respectively thereby completely supporting screw member 41 and strengthening rod member 71.
Extended arm 44 of screw member 41, beyond plain bearings members 32’, threadedly supports a rotary handle 51 through threaded connection 45. The handle 51 is expanded at its rotating end to form a gripping head 52.

The screw 41 and housing 61 pair are used to convert torque into linear force. As the screw is rotated using handle grip head 52, the non-rotating housing 61 moves along the screw 41. Therefore, as the screw 41 is, say tightened, it draws the housing member 61 axially towards the plain bearing member 32 wherein housing member 61 is urged towards plain bearings members 32’ when, reversibly, the screw is counter rotated using handle grip head 52.
In the dressing operation, the dressing machine as discussed hereinabove is placed on and clamped to the work table of the grinding machine through base plate 11. The height of the entire dressing tool can be slidably adjusted using slot 12. The housing member 61 is now set in motion by using handle 51. Dressing tool 81 is adjusted longitudinally of the body by loosening screw in bore 62 and sliding the dressing tool to a position which allows the forward end 82 or inturn the tool tip 83 of the dressing tool to be in close proximity with relation to the peripheral surface of the grinding wheel to be dressed. Screw in bore 62 is then tightened to dressing tool 81 in the desired position. The dressing element 83 is moved in a back and forth using housing screw or side to side motion using screw 41 till the time sufficient particles have been stripped so that the grinding wheel is considered dressed, the dressing machine is withdrawn from the grinding wheel worktable. The entire operation is achieved in a very short time.

Using these steps, the dressing of a grinding wheel while operating at approximately its normal speed of operation by means of stationary and rigidly held dressing tool whereby the unit stress in the minutely small local areas of support of the fine grinding wheel particles are exceeded and locally fractured and the grinding wheel surface is brought to the desired shape.
Validation of dressing grinding wheel has been verified that no appreciable wear is experienced with the dressing tool because of two phenomena, one, the effective adhesive forces between the tiny smooth surfaces of the grinding wheel particles and its matrix is less than the effective adhesive forces of the coarser tiny surfaces of the dressing tool particles and its matrix; and two, the difference in the surface stress levels of the grinding wheel and dressing tool. The grinding wheel is operated at high speed thus the wheel particles are stressed radially by the high centrifugal forces and circumferentially by the commonly known hoop stresses. Both of these stresses add vectorially to produce a high surface particle stress level. The transfer wheel on the other hand is rotating slowly thus its surface particles are stressed negligibly. When both wheels make contact, an additional impulse is transmitted equally to the surface particles of both wheels. This additional impulse stress adds to the already high stress level of the grinding wheel particles so that the total stress exceeds the rupture value between the abrasive particles and its matrix thus tearing the particles from the wheel and dressing the grinding wheel. The additional impulse stress

imposed on the grinding wheel particles is well within the rupture value and particles are not torn loose from the surface of the grinding wheel (transfer wheel). Thus, rotating the grinding wheel at high speeds and the transfer wheel at low speeds enables the dressing operation to proceed swiftly and yet imposes negligible wear on the stationary dressing tool tip 83.
Although the present discussion relates to method and means of dressing grinding wheels, more particularly, the method and means shall enable dressing of grinding wheel, it will be appreciated that the device and methods discussed may be readily adapted for use with other similar procedures. Not only the methods and the tools devised thereof for quality dressing of grinding wheel is cheap and easy to manufacture but also will provide safer and ergonomic means for the operators to deal with the dressing operation. It will be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the invention and are included within its scope.
Furthermore, all examples recited herein are principally intended expressly to be only for pedagogical purposes to aid the reader in understanding the principles of the invention and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Also, the various embodiments described herein are not necessarily

mutually exclusive, as some embodiments can be combined with one or more othe embodiments to form new embodiments.

WE CLAIM :
1) A device for dressing grinding wheels, comprising:
- a base plate 11 having a slot 12 towards its center to act as a rigid base to entire wheel dressing tool;
- a plate 21 T-welded upon the base plate 11 and having holes 23, 22;
- a plurality of inwardly placed L-shaped plates 31, 31’ abutting longitudinally with the Plate 21 such that holes 34, 34’ in the L-plates 31, 31’ match said holes 23, 22 in the Plate 21;
- a plurality of plain bearings 32, 32’ in L-plates 31, 31’ for supporting rotating ends 43, 43’ of a screw member 41, and a plurality of plain bearings 36, 36’ placed in hole 35, 35’ for supporting a strengthening rod 71; the screw member 41 effecting axial movement of a housing member 61 of the dressing tool relative to the screw member 41; the housing member 61 having bore 66 within which the dressing tool 81 is detachably held by means of another screw that uses a bore 62 provided at the top of the housing (61);
- an extended arm 44 of the screw member 41, beyond said plain bearing members 32’, threadedly supporting a rotary handle 51 through a threaded connection 45; and
- a handle 51 is expandable at its rotating end to form a gripping head 52;

2) A method of dressing grinding wheel in a device as claimed in claim 1, said
method comprising the steps of:-- assembling a left hand L-plate 31 on a plate 21 through holes 23 and 34 and
pressing plain bearings 32 and 36 on the L-plate 31;
- pressing a rotating end 43 of a screw 41 into the plain bearings 32 such that a collar face 46 of the screw 41 abuts the L-plate 31;
- mounting a dressing tool housing 61 rotatably and threadedly on the screw 41 to form a screw kinematic pair with the screw member 41;
- passing distal end 72 of a strengthening rod 71 through a hole 64 of the housing member 61 in order to be received in said plain bearings 36;
- fixing free ends 43’ and 72’ in the plain bearings members 32’ and 36’ respectively for completely supporting said screw member 41 and strengthening rod member 71;
- tightening the screw member (41) in bore 62 to fix a dressing tool 81 in the desired position;

- sliding the dressing tool 81 to a position which allows a forward end 82 or inturn a tool tip 83 of the dressing tool to be in close proximity with relation to the peripheral surface of the grinding wheel to be dressed;
- urging the housing member 61 on the screw 41 axially towards or away from the plate 31 using a handle grip head 52;
- moving the tool tip 83 of a dressing machine in a back and forth manner or side to side motion using screw 41 till the time sufficient particles have been stripped so that the grinding wheel is considered dressed; and
- withdrawing the dressing machine from the grinding wheel worktable.