"CREATION OF HYPERBOLIC PROFILE THROUGH SOFTWARE TO DRESS THE REGULATING WHEEL OF CENTERLESS GRINDERS" Field of the invention

The present invention relates to the creation of hyperbolic profile through software to dress the regulating wheel of centerless grinders, which is a technological improvement whose innovation is the total automation of the creation of this hyperbole through a software program that will create the ideal hyperbole profile which will result in a perfect contact line between the two wheels of the machine - the grinding wheel and the regulating wheel.

Centerless grinders are machines that grind cylindrical parts leaving their diameter dimensions within the expected tolerances. The grinding of the parts is done through an abrasive process, using a grinding wheel (which effectively removes the stock material from the cylindrical part) and a regulating wheel (whose function is to rotate the cylindrical part).

Description of the prior art

The most common cylindrical parts machined in a centerless grinder are pins, shafts or plain cylindrical rods, which are ground by a process called "thrufeed", that is, the cylindrical part enter through one side of the machine and leave through the other side. In order to create a resulting force that will "pull" the parts along the wheels, the regulating wheel is inclined in relation to the grinding wheel.

However, this inclination results in a problem: the inclination of one wheel in relation to the other makes the distance between them to be smaller in the middle than at the ends.

To understand this problem, one may simply touch two cylinders against each other - they will touch each other throughout their entire extensions. But when one cylinder is rotated in relation to the other, the cylinders touch each other only at one point in the middle (0), while in

one end, the point (1 ) located in the same line is above the centerline of the grinding wheel and in the other end, the point (2) is below the centerline of the grinding wheel.

This condition is extremely harmful to the grinding process, since the contact between the part and the grinding wheel occurs only at the center, excluding the possibility of the contact in the whole extension of the wheel.

Summary of the invention

In order to solve this problem, a hyperbolic profile is created on the regulating wheel, making its shape to look like an inverted barrel (or an hourglass). With that, when the regulating wheel is inclined, its hyperbolic profile will result on a perfect contact line throughout the whole extension of the wheels.

In the traditional centerless grinders this hyperbolic profile is created through the manual adjustment (A) of the regulating wheel dresser's diamond. The higher the diamond in relation to the center of the regulating wheel, the shallower the hyperbole will be. However, this method is manual, not precise and empiricist, generating difficulties for the machine operator.

Brief description of the drawings

Further characteristics and advantages of the invention are better clarified below by the detailed description of a preferred embodiment of the invention, with reference to the attached drawings, in which:

FIGURES 1 and 2 represent the side and top views, respectively, of the regulating wheel headstock of the traditional centerless grinder.

FIGURES 3 and 4 represent the side and top views, respectively, of the regulating wheel headstock of the new version of centerless grinder, according to the patent.

FIGURE 5 represents the ideal profile of the hyperbole created and that will result on a perfect contact line between the grinding wheel (not shown) and the regulating wheel.

FIGURE 6 represents the positions of the grinding wheel (1 ) and regulating wheel (2) in the traditional machine (A and B) and in the new version (C and D) according to the present invention, where:

- In A (traditional version) both wheels are shown - grinding wheel (1 ) and regulating wheel (2) - paralleled to each other and with the regulating wheel (2) dressed straight (3);

- In B (traditional version) the regulating wheel (2) is shown dressed straight (3) and inclined in relation to the grinding wheel

(1 );

- In C (new version) the correct hyperbolic profile (4) is shown on the regulating wheel (2);

- In D (new version) the regulating wheel (2) is shown with the hyperbolic profile (4) and inclined in relation to the grinding wheel (1) — the ideal condition.

Detailed description of the invention

The innovation of the project herein proposed is the total automation for the creation of the hyperbole (4). An electronic distance sensor will be adapted to the machine to measure the inclination angle (α) of the regulating wheel. This information will be sent electronically to the computerized numeric control (CNC) of the machine.

Another important innovation - the diameter (d) of the part being grounded - will be typed by the operator on the CNCs keyboard. The regulating wheel diameter (DR) is also automatically known by the CNC.

Through a mathematical formula involving these three variables (α, d and DR) the machine's CNC will run a program to create

the ideal hyperbolic profile that will result on a perfect contact line between the two wheels.

This ideal profile is then transformed into synchronized movements of the axes (X and Y), which move the grinding wheel (1 ) and the regulating wheel (2) against the wheel dressers (5) which perform the straight dressing (3) of the grinding wheel (1 ) and the desired hyperbolic dressing (4) of the regulating wheel (2).

The synchronized movements of the axes (X and Y) will then profile the wheel with the desired hyperbole.

This makes the machine easier to operate and makes the regulating wheel's dressing process much faster and more precise.