US2934862A

US2934862A - Method and machine for grinding rolls

Info

Publication number: US2934862A
Application number: US679644A
Authority: US
Inventors: Edward C Fechter
Original assignee: Hamilton Watch Co
Current assignee: Hamilton Watch Co
Priority date: 1957-08-22
Filing date: 1957-08-22
Publication date: 1960-05-03
Anticipated expiration: 1977-05-03

Description

May 3, 1960 E. c. F'ECHTER METHOD AND MACHINE FOR GRINDING ROLLS Filed Aug. 22, 1957 3 Sheets-Sheet l ATTORNEY May 3,' 1960 E. c. FECHTER METHOD AND MACHINE FOR GRINDING ROLLS Filed Aug. 22, 1957 3 Sheets-Sheet 2 INVENTOR EDWARD C. FECHTER ATTORNEY May 3, 1960 E. c. FECHTER 2,934,862 METHOD AND MACHINE FOR GRINDING ROLLS Filed Aug. 22, 1957 3 Sheets-Sheet 3 Fl G 5 INVENTOR EDWARD C. FECHTER ATTORNEY United METHOD AND MACHINE FOR GRINDING ROLLS Edward C. Fechter, Millersville, Pa., assignor to Hamil- ,ton Watch Company, Lancaster, Pa., a corporation of Pennsylvania Application August 22, 1957, Serial No. 679,644

4 Claims. 01. 51-95 This invention relates to a method and machine for grinding rolls for multi-high rolling mills to provide a convex surface on the rolls.

In rolling metal tape to the thinness of one mil or under, an ordinary cylindrical roll will produce distorted edges and, under the abnormally high pressures used in rolling, will produce a tape which is slightly thicker in the shaped by cylindrical grinding with the grinder being moved through an arcuate path by a series of cams to pro duce the desired convexsurface on the roller.

' I have now found that this grinding can be done in a much more efiicient and accurate manner without these cams and relatively complicated equipment. According to my invention a cylindrical roll is rotated on centers while its central portion is deflected or bowed a predetermined distance. A grinder mounted on the opposite side of the roll from the direction of deflection or bow is then moved longitudinally across the roll to remove an accurately predetermined amount of metal from its ends.

It is accordingly a primary object of the present invention to provide an improved apparatus and method for making convex surface rolls.

It is another object of the present invention to so mount a roll on a reciprocating carriage that surface contact with a fixedly mounted rotating grinding wheel will produce the desired convex surface on said roll.

It is a further object of the present invention to provide a method of supporting and rotating a roll for a multihigh rolling mill in such a manner that a grinder wheel may grind a convex surface on the roller.

It is a still further object of the present invention to provide a machine for holding a rotating roll between centers so that a reciprocating carriage may move said roll across the surface of a fixedly mounted rotating grinder in a straight line and produce a convex surface.

The invention is illustrated on the accompanying drawings in which:

Figure 1 is a perspective view of the apparatus used for grinding the rolls;

Figure 2 is a cross-section through the center of the roll;

Figure 3 is a cross-section through the center of the roll, greatly enlarged showing the grinding wheel contact position;

Figure 4 is a perspective view of the roll gripping element;

Figure 5 is a side elevation, partly in section, showing a tape passing between a pair of convex rolls before pressure is applied to the rolls; and

Figure 6 is a side elevation of the rolls of Figure 5 after pressure has been applied showing the roll deforma- 70 tion which occurs to produce a flat uniform tape.

Referring particularly to Figure 1, a fixed longitudinal base 12 with

sliding surfaces

13, 14 and 15 is mounted on a reciprocating carriage 10. This carriage is similar to the movable carriage found on an ordinary cylindrical grinder and contains stop elements and reversing switches so that the travel of the carriage may be controlled within limits. Mounted on the base 12 and slidable on the surfaces, 13, 14 and 15 is a roll gripping central element 16. This element may be positioned and securely locked at any position along the base 12 so that it may be centrally positioned for rolls of different lengths. The table is also provided with a pair of centers 18 (only one of which is shown). These centers are fixed in that they do not rotate, although one is adjustable relative to the other so that rolls of different lengths may be accommodated.

Mounted for rotation between the centers 18 is a roll 20. Also mounted on the slide is a motor 22 driving the roll 20 through a dog 24 so that roll 20 is turned between the fixed centers 18.

Adjacent to the table 10 is a grinding wheel 26 adapted to contact the roll 20 during the reciprocating motion of the carriage, the carriage being adjustable toward and away from the wheel 26 by means of manually operated screws. Carried by the frame supporting the wheel 26 is a retractable rod 28 which has located at one end thereof a measuring dial indicator or micrometer 30 having a contacting pin 32. The measuring dial indicator may be positoned by means of the wing nut 27 so as to contact the roll 20 throughout its entire length during the reciprocation of the carriage. The micrometer and rod may also be withdrawn from the framework and replaced without disturbing the accuracy of measurement.

The center holding element consists of a U-shaped body portion having legs 33 and 35-. Each of the legs has holes 37 for the reception of bolts 34. The

legs

33 and 35 are formed on their under sides with

sliding surfaces

41, 43 and 45 which engage and slide on the

surfaces

13, 14 and 15 of the slide 12. The middle sliding surface 14 is cut away at 47 to provide a projecting edge 38. The bolt 34 carries a head 36 which underlies the projection 38 and securely holds the U-shaped central element in position.

The rod 44 extending between the legs of the U-shaped body portion pivotally supports an L-shaped lever 46 which has restricted motion about the rod 44. The lever 46 is threaded to receive in its upper portion a bolt 48 adapted to securely and adjustably hold a stop 50 in position. A similar bolt 52 is carried at the lower end of the lever and adjustably positions a wedge-shaped toe indicated generally at 54. The lever 46 is further formed with a central opening 56 so that an adjustably mounted V-shaped rest 58 may pass through the lever and contact the roll 20.

Stop 50 is recessed in its center portion and slotted at 57 so that it may be positioned by vertical adjustment within the limits of the slot. The bottom surface of the stop 50 is formed with two substantially square shaped feet 59 which contact the upper surface of the roll 20 to limit its upward movement. The wedge shaped toe 54 is similarly formed with a slot 60 for vertical adjustment within the limits of the slot. The upper surface of the toe 54 has a wedge shaped face 62 and a portion cut away for clearance at 64.

The upper end of the L-shaped lever 46 has a pin 65 which pivotally supports a spring loaded bolt 66. A yoke 68 is secured to a base 70 and mounted on the U-shaped body portion to receive the end of the spring loaded bolt 66. An adjusting nut 72 is carried between the yoke and is threaded on the bolt 66 to move the lever 46 about the pivot pin 44.

Located in the central portion of the U-shaped cen tral holding member is the V-shaped rest 58 which extends through the hole 56 in the lever 46, and is pivoted to the end of a cylinder 74. The other end of this cylinder is slightly enlarged and formed with threads 76 so that the V-shaped rest may be moved toward and away from the roll 20 by turning the knurled head 78. A locking nut 80 holds the cylindrical member 74 and the V-shaped rest securely in adjusted position so that the roll 20 is held in a bearing consisting of the upper stop 50, the V-shaped rest 58 and the wedge shaped toe 54.

In the operation of the machine the roll is placed between centers 18 and the dog 24 attached to the roll so that the motor 22 may rotate the roll between centers. The rod 28 is advanced (by movement of the carriage toward the grinding wheel) until the contacting point 32 of the micrometer 30 is in contact with the roll and the roll is checked for trueness in mounting between the centers. The roll gripping central element 16 is then moved into position so that the feet 59 of stop 50 are brought into contact with the top of roll at its exact center. The screw 48 secures the stop 50 in position so that movement of the roll upward is impossible. The wedge surface of the toe 54 is then moved into contact with the lower surface of the roll shown in Figure 3, and the screw 52 secures the toe in this contacting position. The thumb screw 72 is then turned to rock the lever 46 about the pivot rod 44 forcing the dog into firmer contact with the roll and causing the roll to bend at the center. This degree of bend is in the nature of from A: to IO-thousandths of an inch (.005 inch to .010 inch) and a second measurement is taken by means of the micrometer 30. When the degree of bend is shown to be sufficient to produce the convex surface desired, the rest 58 is moved into contact with the roll to give it a backing support. With rest 58 in position the roll is held in the bearing consisting of the feet 59 the rest 58 and the wedge surface 62 and between the centers, causing it to rotate eccentrically. The carriage supporting the rotating roll is moved in the direction toward the grinding wheel 26 until contact is made with the ends of the roll. The carriage is then automatically moved back and forth across the grinding wheel until the wheel is taking a cut across the complete surface of the roll. The micrometer is again brought in use to measure and ascertain if the correct convex surface has been ground on the roll.

It will thus be apparent that by means of this apparatus it is possible to provide accurately contoured convex rollers without a large amount of complex and expensive equipment. stitutes the only measuring device necessary to secure high standards of accuracy.

A simple micrometer type dial gauge con- The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. a

What is claimed and desired to be secured by the United States Letters Patent is:

l. A method of grinding rolls for multi-high rolling mills comprising rotating the roll between centers, bowing said roll by pressure exerted at the roll center, securely holding said roll against other than rotary motion in said bowed position and grinding said rotating roll on a line parallel to said centers.

2. An apparatus for grinding a convex surface on a roll comprising a base, means mounting said base for reciprocating motion, a pair of fixed centers carried by said base and adapted to support a work piece between said centers, means for rotating said work piece, means carried by said base for gripping said work piece centrally and bending said work piece relative to a central line between said centers, said gripping means including adjustable guides for preventing displacements of the center of said roll in a direction perpendicular to the direction of said bend, and means for grinding the surface of said work piece during the rotating and reciprocating motion of said work piece.

3. An apparatus for surface grinding rolls for multihigh rolling mills comprising means for mounting said rolls for rotation about a longitudinal axis and for reciprocation along said axis, means for gripping said roll to bend said roll from its normal longitudinal position, said gripping means including means for fixedly securing said roll in said bent position, and means for grinding said roll during rotation and reciprocation.

4. An apparatus as set out in claim 3 wherein said gripping means is mounted on the same base as said mounting means, and said grinding means is mounted on the other side of the roll from said gripping means.

References Cited in the file of this patent UNITED STATES PATENTS 1,317,713 Linder Oct. 7, 1919 1,338,178 Henderson Apr. 27, 1920 FOREIGN PATENTS 767,247 Great Britain Jan. 30, 1957