US2592606A - Bar miller - Google Patents

Description

April 15, 1952 T. s. sEE ETAL BAR MILLER 3 Sheets-Sheet 1 Filed Feb.` 10, 1948 April 15, T S SEE ETAL 2,592,606

` BAR MILLER Filed Feb. 10, 1948 3 Sheets-Sheet 2 ulm A M MW April 15 1952 T. s. SEE ETAL 2,592,606

BAR MILLER Filed Feb, 10, 1948 3 Sheets-Sheet 3 Patented Apr. 15, 1952 BAR MILLER Theodore S. See, Hammond, Ind., and Horace A. Frommelt, Milwaukee, Wis., assignors to La Salle Steel Company,

tion of Delaware Chicago, Ill., acorpora- Application February 10, 1948, ScrialNo. 7,375

4 Claims. l This invention relates to a machine for milling metal bars and more particularly to an improved machine for milling metal bar stock other than rounds. Such stock includes squares, flats, hexagons and what are termed special sections. This latter term indicates an elongated metal article of uniform, cross section, the crosssectional shape thereof being neither square, flat, hexagonal, octagonal nor round.

`The invention has for an important object thereof the provision of a new and improved machine ofthis character which is operable at much higher speeds than heretofore deemed possible and which is flexible in design and adjustment in order to` enable it to be set up quickly and with greater facility than the machines of the prior art to operate on metal bars, including special sections, of various shapes and sizes.

A feature of the invention which contributes to the `accomplishment of the foregoing objectr consistsl in providing, in a machine of this character, a plurality of independently adjustable cutters, positioned in tandem with respect to one another, each cutter being preferably driven at speeds in excess of those heretofore employed in the art. -In copending application Serial No. 7,372 led February 10, 1948, in the name of one of the instant inventors there is disclosed an improved milling process for` steel and its alloys and also a machine for practicing themethod in the milling of round bars. The present invention may, in some of its aspects, be regarded as residing in the provision of la novel machine capable of applying the method of the copending application to the milling of metal bars other than rounds. Primarily the novelty of the method phase of this development, of which the instant application is a part, relates to steel and its alloys although many features yof the development such as theapparatus, cutters, etc., are not to be confined to such materials but will apply with equal force to the milling of other ferrous, as well as non-ferrous metals.

Furthermore,` although both this and the copending application disclose machines for milling bars, the invention, including the method, may be employed in a novel manner in milling such additional products as billets, slabs, blooms, rounds, tube rounds, etc., as wellas apparatus, devices, articles and `machines. manufactured from such products.

A further feature of the invention which contributes to the flexibility of the machine herein disclosed consists in the provision of a novel cutter assembly in which the milling cutter, madcpl'ff,"

erably of a carbide material, is made up of a' plurality of sections, keyed and clamped together to form a complete assembly. In accordance With this feature of the inventiontheparts or sections of various cutters may be interchangedV withone another to adapt the assembly tooperateon bars of various shapes, sizes and cross sections thereby avoiding the necessity of providing separate, complete cutters for each diierentsize crshape of bar. y Other objects `and features of the invention will become apparent from a readingof the following speciilcation` in the light of the accompanying drawings, in which,

Figure 1 is a diagrammatic View oi a milling machine constructed in accordance with the present invention;

Figure 2 is aview in front elevationof a single stand, or assembly, oi` a cutter and guide shown, inplurality, in Figure 1;

Figure 3 is a View, partially in section,` ofthe stand orassembly shown in Figure 2 4Figure 4 is a View, in front elevation, showing the manner in which the cutter and guide Iare driven;

Figure 5 is a view inside elevation of the constructionshownlin Figure 4 Figures 6 to 9 inclusive illustrate the component parts vof a typical cutter assembly constructed in accordance with: the present invention, and

Figure 10 shows three typical special sections made from bars of different shapes. 4

As diagrammatically shown in Figure l ofthe drawings, the machine comprises a suitable num-V berof stands or assemblies A, B, C, etc., each of which, as illustrated, is made up of a cutter Ill and a guide roll I 2- cooperating therewith. `A work piece i4, which for purposes of description, may be regarded as a square is shown passing through the machine, `and.- more specifically, passing between the cutters lil and the cooperating guide rolls-I2.` It will be understood that the cutters Ill will'mill the top and bottomfsurfaces of the bar and inlorder to accommodate barsof different thicknesses or shapes. the distance between the guide rolls and cutters may be increased or decreased through the provision of adjusting means which will presently be described.

In order to mill the sides of the bar as it passes through vthemachine the latter is provided with a second series of stands or assemblies M, N, O, etc., each of whichas illustrated, comprises a cutter il) and a cooperating guide roll |2.` It will be appreciated that a greater or lesser num- 55 ber of stands or assemblies A, B, C, MiN.` 0. eww

may be provided, as desired, in accordance with' the demands of the work being performed by the machine. Also it is not necessary to operate simultaneously all of the stands or assemblies with which the machine may be provided. Certain of them may remain idle during a given milling operation but may be brought into operation during another. Additionally, the arrangement of cutters and guide rolls, as illustrated in Figure 1, may be changed, as desired, without departing fromV the scope of the invention as herein set forth. Thus, the vertical cutters and guide rolls M, N, O might be interposed between the horizontal cutters and guides A, B, C to .provide alternate horizontal and vertical stands. Various other permissible and contemplated arrange-l ments of the stands as Well as the cutters and guide rolls within the stands will occur to those skilled in the art.

vFeed rolls I6 and I8 may be provided, and, if desired, burnishing rolls 28 and 22 maybe added. These latter operate at surface speeds above the rate of feed of the bar to impart a burnishing action thereto. Similarly, the guide rolls I2 may rotate faster than the bar moves toobtain the burnishing action.

As. hereinbefore sety forth, the machine is so designed as to obtain a maximum amount of flexibility in operation in order to render it capablelofmilling bars of various shaps and sizes, including hexagons and octagons as well as bars having cross-sectional contours of irregular shape, which latter are known in Vthe trade as special sections. To this end, as shown in Figure 2, the cutter lil and guide roll I2 are mounted in a hood or casing 24 which, in turn, is mounted for rotation within an outer frame or casing 26.` Roller bearings 28 facilitate the rotation of the hood 24 within the casing and,

as shown in Figure 3 these members may be provided with collars 30 having engagement with an annular groove 32 formed in the outer surface lof thehood 24. VMembers 33 are provided for the purpose of maintaining the hood 24 in proper position within the casing 26 and a rack 34 provided with a pinion 38 afford means for adjusting the rotary position of the hood 24 within the frame 26. A hand operated member 48 is provided for driving the pinion 36 although it will be appreciated that this membery may be replaced by electrically driven means, remotely controlled, if desired.

s Turning now to Figures 4 and 5, it will be observed that the cutter I0 is mounted on a shaft 42 which is rotatably driven by means of high speed'motors 44 and 46 mounted on platforms 48 .and50 carried by the hoodv 24. The guide roll I2 is mounted on a shaft 52 which, through interconnections, is driven by high speed motors v54 and 56. These latterdrive bevel gears 58, 88 which have driving engagement with cooperating bevel gears 82, 84 carried by sleeves 68, 88 splined to shafts 1D, 12. Thus the latter rotate Vwith the sleeves 86, 68 but are free to move upwardly or downwardly through such sleeves.

At theirupper extremities the shafts 18, ,12 carry bevel gears 14, 'I6 which have driving engagement with bevel gears 18, 8|] fixed to the opposite ends of the guide roll shaft 52. The bevel gears 14'1'I8Yand '18, r8i! are constantly in driving engagement with one another owing to the fact that they arermounted within bracketsr 82, 84.

Examining one of the brackets, for instance the one which appears `to the left of the guide roll I2, as shown in ,Figure 4, an integrally formed arm 88 extends outwardly therefrom and carries a bushing 88 within which the shaft I0 freely rotates. A second arm 98, also integrally formed with the bracket 82 extends rearwardly and carries a bushing 92 within which the guide roll shaft 52 freely rotates. Thus the arms 88 and 28, being formed integrally with bracket 82 move up and down as a unit and at all times the bevel gears 14 and 78 remain in driving engagement with one another. Inasmuch as the bracket 84 which supports the bevel gears 80 and 'I8 is identical to the bracket 82 no detailed description of it need be given.

YIn order to vary the position of the brackets 82 and 84 and thereby to control the distance between the cutter I8 Vand the guide roll I2, the brackets are mounted on screw threaded shafts 94, 95, rotation of which causes the brackets to move uniformly upwardly or downwardly thereby changing the position of said guide roll I2. Rotation of the shafts 94, 95 is accomplished in the following manner. The shaft 94 is extended anbd carries at its lower extremity a bevel gear 98 having screw threaded engagement with a bevel gear Hi8 carried on the inner end of a handoperated adjusting means |82. The upper portion of the screw threaded shaft passes through a bushing I4, carried by a bracket |86, and has 4 a gear E88 afxed to its terminal portion. A

chain IBS is provided for the purpose of transmitting rotary motion from the shaft 94 to the cooperating shaft 85. Thus movement of the hand-operated member |82 causes theV shafts 94, 96 to rotate in one direction or the other, therebymaking the guide rollv I2 move toward or away from the cutter I8.

The latter member, namely the cutter IU is mounted on a shaft l Ill which is carried by bushings I I2, I i4 formed integrally with the brackets |86, I 87.' The shaft is provided with clutch couplings I I2a, and II4a which may be quickly and conveniently disconnected to permit ready interchangeability of cutters.

As previously'mentioned, one of the most irnportant features of the invention is its great flexibility of set-up and operation which enables it to operate satisfactorily on bars of regular cross-sectional contour such as squares, flats, hexagons and the like and also on bars of irregular cross-sectionalcontour known as special sections. In milling ats and squares, only horizontal cutters and guide rolls for the top and bottom of the bar and vertical cutters and guide rolls for the sides will be required. On the other hand, in milling a hexagon, for instance, in one pass or operation, it will be necessary to rotate at least two of the stands or assemblies A, B, C, etc., M, N, O, etc., into a position such that cutters In will be positioned to mill the two addi tional faces presented by the bar. In the case of octagons, four of the stands or assemblies will be rotatably positioned to operate upon the four additional faces that are presented. Thus the machine can be quickly and easily adjusted to accommodate these different types of bars and to facilitate matters in setting the machine for these different purposes it is proposed to employ an indicator and corresponding indicia in connection with each stand or assembly A, B, C, X, T, N, O, to record visibly its exact setting.

Coming now to the operation of the machine in milling special sections, i. e., bars having irregular cross-sectional contours, Figure l0 shows these or other such shapes with the same facility and rapidity as flats, squares,rhexagons and the like. Tothis end it is nowproposed to `employ cutters and guide rolls of a; special design that are shaped to conform to the shape ofi the special section being milled. `It is further proposed, in order to reduce the cost` of Acutters and possibly guide rolls, to build them upin interchangeable sections which can be assembled to provide a unit shaped to conform. to` the` contour of the bar being milled.. i

In Figures 6 and 7 there is shown a cutter of the type disclosed incopendingapplication Serial No. 7,372, referred to above. Such a cutter is monolithic in construction andl is made, for example of so-called hard metal. The so-called hard metal is usually an alloy of carbides, borides, nitrides or silicides and the cutter comprises a body portion |20 integrally formed of such metal and provided on its exterior, peripheral cutting face with a series of ground, spiral or helical cutting teeth |22. These teeth have a minimum or near minimum pitch and the cutter itself is mounted for rotation at abnormally high speeds in accordance with the process disclosed in the copending application mentioned. Thus the pitch of the cutting teeth Will lie within the range of from 1454 of an inch to l inch and the teeth are moved at a linear speed in excess of 1000 feet per minute to bring them into instantaneous contact with the metal work piece.

Figures 8 and 9 illustrate a segmental or builtup cutter intended for use in milling special sections, such, for instance, as that indicated by the letter Z in Figure 10. Referring to Figure 9, the cutter assembly comprises a cylindrical portion |30, a central grooved portion |32 and a second cylindrical portion |34 adapted to be held in assembledposition by means of bolts extending through the members and also through annular clamping members |36, |38. As illustrated by means of dotted lines, the openings |40 extending through the cutter segments are of a diameter greater than the diameter of the bolts passing through them to allow for expansion during operation of the cutter. i

In milling a bar of the shape indicated by the letterfZ, the cylindrical portion |30 of the cutter and the flange |50 of the cutter |32 will mill the stem |52 of the bar and the grooved portion of the cutter |32 Will mill the rounded head |54 of the bar. The cutter |34 will not be required for this particular operation. It will be understood that in an operation of this nature, the guide rolls which cooperate with the cutters will be correspondingly shaped to accommodate the side of the bar lying opposite to that engaged by the cutter. The number of stands or assemblies A, B, C, etc., and M, N, O, etc., that are employed for the purpose of milling the bar Z Will be optional, it being observed however that at least one stand or assembly will be disposed in such a manner as to mill the ilat face |56 of the bar.

In milling the bar X various types of operations can be carried out by the machine. The stands M, N, O, etc., might be employed to machine the side edges |58, |60 and the stands A, B, C, etc., to mill the top and bottom surfaces |02, |64, including the areas |65, |68. Here again the hard metal cutters and the cooperating guide rolls would be shaped to conform to the contour of the bar and such areas as 180 and |08 would be milled by cutting teeth formed on the face of the cutter. such as the face |10 as shown` 5 half ovals, halfrounds, beams, channels; squares,

flats, hexagons, etc.

A typical milling operation performed in accordance with the present invention may bedescribed as follows: A cutter provided with car- 10 bide cutting teeth, driven at an R. P. M. of approximately 1500 and having a diameter of approximately 4 inches mills a fiat bar to a depth of approximately g1g `of an inch. The bar iiat duringthis operation is fed at a rate of 600 inches, or 50 feet, per minute and approximately 18 cubic inches of metal is thereby removed per minute. This operation 'can be performed with a` four inch cutter, having al@ inch pitchvand a 221/2 degree helix, on cast iron having a Brinell 20 hardness of 200 or steel of the grade C 1020 having a Brinell hardness of 180. It is to be understood that the helical angle of the cutting teeth may vary, but ordinarily it will lie within the range of from 10l degrees to 30 degrees. The

teeth themselves may have a 0 degree radial angle and the cutting extremities thereof may be provided with a desired negative angle such as 10 degrees.

Additionally, it is once more pointed out that the invention may be employed to operate on rough products such as billets, slabs, blooms, and the like, as will be readily apparent to those skilled in the art, without departing from the spirit of the invention as set forth in the appended claims.

Having thus described the invention, What we claim as new and desire to secure by Letters Patent of the United States is:

l. A machine for milling metal articles other than rounds, said machine comprising a plurality of stands, each of said stands including ya cutter having a longitudinal axis, a cooperating ,guide roll mounted to engage a surface of said work opposite from said cutter and having a longitudinal axis, means for rotatably driving said cutter and roll about said axes, and means for simultaneously angularly adjustingthe longitudinal axes of the cutter and roll and driving means therefor to predetermined positions throughout an arc of 180.

2. A machine for milling metal articles other than rounds, said machine comprising a plurality of stands, each of said stands including a cutter having a longitudinal axis and having cutting teeth on the periphery thereof of a, pitch not greater than one-half inch, a cooperating guide roll having a longitudinal axis, means for simultaneously angularly adjusting the longitudinal axes of the cutter and roll to vpredetermined positions throughout an arc of 180, and

means for rotating the cutter in said adjusted positions at a surface speed in excess of 1000 linear feet per minute.

3. A machine for milling'metal articles other than rounds, said machine comprising a plurality of stands, each of said stands including a cutter having-a longitudinal axis, a cooperating guide roll having a longitudinal axis, means for rotating the longitudinal axes of the cutter and roll through an arc of 180, the said cutter being shaped to conform to the contour of the article being milled, means for rotating the cutter at a surface speed in excess of 1000 linear feet per minute, and means for rotating the guide roll` at a surface speed in excess of the rate of feed of the metal article to impart a burnishing action to said article.

4. A machine for milling metal articles other than rounds comprising a plurality of separate stands, a cooperating cutter and guide roll at each stand mounted for rotation about parallel axes, means at each stand for angularly` adjusting said parallel axes to predetermined positions throughout substantially 180 to cause the cutters at the individual stands to engage selected surfaces of the article being milled, and means at each stand for rotatably driving the associated cutter about its axis in said positions.

THEODORE S. SEE. HORACE A. FROMMELT.

REFERENCES CITED The following references are of record in the iile of this patent:

8 UNITED STATES PATENTS Number Number l 212,959

Name Date Mathias Nov. 23, 1920 Kessler Mar. 9, 1926 Kessler Jan. 8, 1929 Carroll ----1 Dec. 10, 1935 Coryell Oct. 12, 1937 Murray Aug. 3, 1943 Reaney Aug. 31, 1943 Aber Mar. 28, 1944 Goldsmith Nov. 26, 1946 FOREIGN PATENTS Country Date Germany Sept. 4, 1909

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