US1722995A - Die mechanism and extrusion method of forming metal articles - Google Patents

Description

Aug. 6, 1929. F. w. BURGER ET- AL DI E MECHANISM AND EXTRUSION METHOD OF FORMING METAL ARTICLES Filed March 10, 1924 4 Sheets-Sheet 1 Aug. 1929- F. w. BURGER ET AL 1,722,995

DIE MECHANISM AND EXTRUSION METHOD OF FORMING METAL ARTICLES Filed March 10, 1924 4 Sheets-Sheet 2 g- 1929- F. w. BURGER ET AL 1,722,995

DIE MECHANISM AND EXTRUSION METHOD OF FORMING METAL ARTICLES Filed March 10, 1924 4 Sheets-Sheet 3 zg W 27% Patented Aug. 6, 1929.

UNITED STATES PATENT OFFICE.

FREDERICK W. BURGER AND BERGER STOCKFLETH, OF NILES, MICHIGAN, ASSIGNORS TO EYDRAULIC PRESSED BEARING COMPANY, OF WILMINGTON, DELAWARE, A

CORPORATION OF DELAWARE.

DIE MECHANISM AND EXTRUSION METHOD OF FORMING METAL ARTICLES.

Application filed March 10, 1924.

-Our invention relates to improvements in methods and means for producing metal articles by means of pressure. The object of our invention is to provide improved means and methods for producing metal articles by means of pressure and out of malleable metal, the specific object of our invention being the production of bearings from such metal as babbitt or other metals having similar characteristics. By similar characteristics we mean metal which have a softer base containing harder wearing particles distributed through the base. Such metals are typified by Babbitt metal which consists of a lead or zinc base with tin antimonoid crystals or hard particles of other materials, such as copper particles; the latter are knownto the trade as lead copper metals.

A particular object of our, invention is to provide a practical means and method of carrying into practice our invention of a novel bearing as disclosed in our copending application S. N. 539,550, filed February 27th, 1922, since matured into Patent No. 1,492,119, issued April 29, 1924, wherein the method of producing bearings or bearing liliings by pressure is disclosed, such method including the idea of preserving the virgin or original structure of the metal, or, in

other words, the original size and distribution of the harder or wearing particles in the softer or base metal.

This present application is in the nature of a continuation in part of our said original application. One important feature of our present application relates to the method of control by which we are enabled to obtain pressure enough within the die mechanism to form the nietal articlesiand to preserve the die mechanism against destruction from too great a pressure.

Our original invention includes the idea of heatingthe metal only to that tempera- 'ture at which the soft base is sufliciently malleable to permit the mass of metal to be pressed into the shape desired without producing fissures or cracks therein, or if such are produced sufliciently malleable to cause the elimination of such faultsby the final pressure to which the article is subjected.

A further result which it is our object to obtain is that of compacting or compressing Serial No. 698,123.

may escape from the die cavity. By controlling the shape and area of such outlets we are enabled in any given instance to'produce just the quality of bearing desired and prevent undue strains being developed in the mechanism used for producing the formmg pressure.

Another feature of our invention relates to the j oining of the malleable'metal to a harder metal back, such as a brass back or shell for a babbitt lined bearing. It has long been common practice to tin the inner surface of a bearing shell and then cast a Babbitt metal lining, the heat of the molten babbitt causing it to be firmly soldered to the shell through the medium of the tin which was first applied to the shell. In the present method we particularly wish to preserve the origimil'structure of the bearingmetal and consequently we only apply sufficient heat to make the soft metal base malleable but not sufiicient to melt it. We have found that by direct pressure alone it is somewhat difiicult to cause the bearing metal to adhere to the tinned surface of the shell. However, when we cause the bearing metal, in the forming process, to How over the tinned surface under the heavy pressure which we employ, we cause a perfect metallic joining of the bearing metal to the backing. and motion heat is generated at the contact ing surfaces sufiicient, possibly, to melt the tin solder with which the shell is coated, or possibly the molecules of the two metals are brought into such intimate relations that they become as one piece. But regardless of the true theory of the action we are enabled to cause the lining to adhere to the shell and produce lined bearings of high quality w thout changing or disturbing the original structure of the metal.

A further feature of our invention relates to the die mechanism which we have devised with which to practice our metal article By such pressure forming inventions, and has special referthe outlets to .provide restricted outlets through which the surplus metal can exude, and by means of which theforming and compacting pressure is limited asatisfactory and safe point. G

Our invention will be more readily understood by reference to the accompanying drawings, forming part of this specification, and in which we have illustrated a die mechanism which we have found best adapted to the practice of our invention.

In said drawings Figure 1, is a top plan View of our novel die mechanism;

Figure 2, is a vertical sectional view of the press 011 the line 22 of Figure 1 and showing a front view of the die and punch mechanism;

I, Figure 3, is a fragmentary Vertical sectiona-l view on the line 3..3 of Figure 1; Figure 4, is a vertical sectional view on the line 44 of Figure 3;

Figures 5 and 6 are vertical sectional Views on thelines 55 and 6-6, respectively, of Figure 2;

Figure 7, is a fragmentary plan section on the line 7-7 of Figure 2;

Figure 8, is an enlarged vertical cross section of the die and punch similar to that shown in Figure 2;

Figure 9, is a similar view showing the means employed to change the forming pressure; 7

Figure 10, is a bottom plan view of the punch;

F igure 11,'isa top plan view of a line half-bearing-such as would be produced in accordance with our improvement; and

Figure 12, is a similar View of a halfbearing formed wholly of the.bearing metal.

The device which we have found best suited for practicing our invention com- 7 prises an ordinary punch or pressurepress provided with special bearing forming die parts. In the drawings, we have only illustrated the special parts whichwe have to add .to an ordinary .press to practice our invention. The really essential parts comprise a die member 1 having a die space 2 formed therein of the shape and conformity of the outer surface of thebearing to be produced and a cooperating punch member- 3 having an operating punch member or forming block 4 adaptedto cooperate with 'the die space 2 when brought to'closed position, as illustrated in Figures 3 and 4:, to

cause a fragment or block of the Babbitt metal 5, see Figure 2, to assume-the shape desired. This desired shape is best shown in Figures 11 and 12. In Figure 11, we have illustrated a half-bearing 6 composed of an outer semi-cylindrical backing 7 and an inner Babbitt metal lining 8. Preferably the backing has narrow outwardly ex tending circumferential flanges 9 at its ends The die member 1 is mounted upon a suitable bed plate member 12 and is adapted to be moved from front to back-of the press to position the die 2 below the plunger 3 at the inner limit of its movement and at the otherto be withdrawn from the punch toward the front of the machine so that the fiormed bearing. can be removed from the (1e. 1'

As'best shown in Figure 4, the die cavity 2 is mainly formed in the upper surface of a central member 13, being a part of the die member 1 and at each side, that is at the forward and rear sides of this central member 13 are cross-bars 14, being part ofthe die member 1. Each of these cross-bars has'a flange 15, the upper edge 16 of which forms that portion of the die in which the flanges 10 of the bearings are formed. These cross-bars 14 .are clamped or bound together by plates 17 and bolts 18, which plates extend across the upper surface of the ends of the projection 13, as best shown in Figure 1.

For the purpose of partially closing the die at the upper edges of the bearing we provide laterally 'movingplunger members 19, the inner ends 20 of which are adapted to be projected toward each other, thatis toward the center of the diea s'uflicient distance to cause them to close over the outer part of the top of the mold space. These plungers are guided ontop of the top surface of the part 13 of the die and beneath the tie plates '17 and are adapted to be moved out and in, that is transversely of the die mechanism as the die is moved back and forth on the base plate. 12. As best shown in Figure 2, the base 12 has side members 21 which rise at either side of the die mechanism and guide the member 1 in its back and forth movement. These side members carry under guides 22 which project 1 I minate at 26, Figure 1,; so that when the die mechanism is drawn forward they can be llfted up to forcibly lift the bearing which has just been formed, engaging the bearing by the flanges and forcing it upwardly free of the die space 2. For effecting the movement of the die member back and forth on the base plate 12 we provide a yoke member 27 having side arms 28 connected by a cross-bar 29. The rear ends of the side arms are mounted upon horizontal shafts 30 extending outwardly from the outer ends of the plungers 19. These shafts 30 extend beyond the side arms 28 and carry cam spools 31 on their outer ends, these spools being held against removal from the shafts by suitable nuts 32.

Upon the top surface of the side parts 21 of the base plate 1, we provide cam bars 33 and 34 adapted to enter between flanges 35 on the cam spools 30 and as the die member is moved outwardly to cause the plungers 19 to be withdrawn from their inner operating positions and as the die mechanism is moved inwardly to position the die in working relation to the punch, these cam bars serve to cause the plungers 19 to be forced inwardly to operating position. The inner ends 36 of the side bars 28 of the yoke 27 are formed into lifting projections extending rearwardly from the shafts 30-and when the die mechanism has been fully withdrawn the lifting of the handle end 29 of the yoke serves to lift the cross bars 14 through the medium of the plungers 19 and the tie plates 18, and whereby the bearing which has ust been cast can belifted out of the die, the plungers 19 at this time having been withdrawn from their positions Where the inner ends extend over the edges of the bearing.

The plunger 3 comprises a main member or casting 37 adapted to be removably secured to the vertically movable head 38 of the press upon which the die mechanism is used.

This head 38 is adapted to be reciprocated up and down and force the plunger down into the die member 2 with force sufiicient to form the mass of metal 5 into the space provided between the operating punch member 4 and the die to produce the bearing. The block 4 is adapted to be secured to the member 3 by a horizontal pin 39 which extends through depending portions 40 between which the block 4 is received, the pin 39 preferably being arranged in axial alignment with the center line of the bearing sleeve to be produced. The forming blozk 4 is provided with depending end portions 41 which are spread apart the length of the bearing to be produced and when closed upon the die, these depending portions 41 descend and engage the outer faces of the upwardly extending flanges 15 on the members 14, thus tightly closing the ends of the space in whichthe bearing'is formed. As best shown in Figure 3, the lower longitudt nal sides of the. part 3 of the plunger are cut away, as shown at 42, to provide spaces 43 adjacent the inner ends 20 of the transverse plungers 19 into which'any surplus metal can be forced. As the plunger 3 descends and forms the metal into the die space the pressure will be relieved and the destruction of the mechanism prevented by allowing the excess metal to exude into the spaces 43.

In the formation of the bearing, the surplus metal, shown at 44, adheres to the bearing and is severed from the bearing in a following operation which it is not deemed necessary to describe herein.

Preferably the plunger member is provided. with a center button or projection 45 on its under side adapted to produce an oil hole or opening 46 in the bearing and the plunger is preferably provided with diagonally arranged rounded ridges 47 for producing diagonal oil grooves 48 in the bearing. Furthermore, we preferably provide strips or bars 49 in the plunger member at the upper side edges of the bearing adapted to produce longitudinal cut away portions or oil grooves '50 at the upper longitudinal edges .of the bearings produced.

in fact the bearing when it leaves the press is ready for use without further operations except merely the removal of the surplus or excess metal 44 which can be accomplished by means of suitable simple cutting devices.

In our method of producing bearings, if the bearing is to have a hard metal backing we first form the hard meta-l backing 7 preferably out of sheet metal by means of suitable forming dies and then we coat the inner cylindrical surface of the backing and the outer end surfaces of the flanges 9 with some softer adhering metal, such as a suitable solder. Then when the die member is withdrawn from beneath the plunger, as has been described, the backing is laid in the die member in the proper position, the end flanges 9 engaging the outer sides of the center projection 13. Then a piece 5 of the Babbitt metal, previously heated, as has been described, to make it malleable, is placed in the die upon the backing already in position. Then the die mechanism is pushed in under the plunger and is adapted to be set in central position by means of a rear stop 51 secured to the base plate 12. During the forcing inwardly of thedic mechanism the transverse plungers 19 are forced toward each other and engage over the upper edges of the backing thereby holding it accurately in central and true position. Then the plunger is forced downwardly into the die and the mass of bearing metal 5 is forced by means. of the heavy pressure into the space between the plunger and the die, that is between the plunger and the backing when the backing is used and in this operation under the tremendous pressure required the plained, and in such flowing over the pose the operation is substantially the same the extrusion of metal from the die mechanism in the bearing forming operation.

3. In a die mechanism of the kind described for forming a bearing lining in a harder metal half cylindrical shell, means metal is compacted and caused to adhere to the inner prepared surface of the backing so that when the bearing is removed, the backingand the bearing metal lining constitutes a unitary member, the bearing metal being molecularl joined to the backing through the medium of the solder coating on the backing. The heavypressure causes the excess metal to flow out of the die, or in other words, be extruded,.as has been exdrical shell comprising plungers movable in and out and adapted to be moved inwardly to overlap the upper edges of the shell, as and for the purpose specified. I

4. In a die mechanism of the kind described, a suitable die for receiving a half cylindrical bearing shell, plungers movable inwardly to engage the edges of the shell to retain it in place and preventits extrusion under the heavy pressure used, the inner ends of the plunger-s ending substantially soldered inner surface of .the lining sufiicient heat is developed to cause the bearing metalto be molecularly joined to the solder. We-have found that it is best to allow the excess metal to flow freely over the edgeof the lining andconsequently we do not permit the inner ends 20 of the plungers' 19 to project inwardly beyond the inner edge of the lining. When it is desired, in order to increase the forming pressure for any reason, we do this by providing outwardly projecting shoulders 52, Figure 9, on the sides of the plunger member 3 which partially close the outlets of the die and make extrusion more diflicult. By this means we are enabledto control the forming pressure to produce the best results in relation to the particular metal being used.

Insome instances it is desired to make bearing linings of Babbitt metal only with out the hard metal backing and for this purfor the purpose specified.

'5. A die mechanism for forming relatively soft metal to desired shapes by'pressure, the mechanism including a die and a cooperating plunger, the die having. an open side through-which the plunger enters, an openbeing formed .can be extruded and means for changing ,the area of said opening to change the forming pressure.

6. A die mechanism for forming relatively soft metal to desired shapes by pressure, the mechanismincluding a die and a cooperating plunger, the die having an .open side through which the plunger enters, openings being provided at the sides of the plunger through which the metalbeing formed can be extruded, and means for changing the areas of said openings for changing the maximum forming pressure.

7. A die and coo erating plunger mechanism for forming earing metal into hearing shells of desired dimensions and density, the die having an open side through which the plunger enters, extrusion openings being provided through which excess bearing metal may escape and means for changing .except that the harder metal backing is omitted and a larger mass of the Babbitt metal is used, being sufficient to form the complete bearing of Babbitt metal.

As many modifications of our invention will readily suggest themselves to one skilled in the art, we do not limit or confine our invention to'the specific steps of. procedure or to the specific details of construction herein shown and described.

We claim: I

1. In a die mechanism for the purpose described, means forming an outlet throu h which excess metal can be forced out of t e die space upon the closing of the die, and means for partially closing said outlet to make the extrusion of the excess metal moredifiicult.

2. The improvements herein described, comprising a bearing forming die mecha-' nism, including a half cylindrical die and a cooperating plunger, side members movable in to project over the side parts of the die for holding a bearing linin in the die, the plunger bemgprovided wit side shoulders of greater or less dimensions adapted to 'project toward the side members for controlling ing the forming pressure.

sired density, and including a die and a cooperating plunger, extrusion openings being provided through which excess bearing metal may escape and means for changing said openings for inversely changing the forming pressure.

ruary, 1924.

FREDERICK. w; BURGER. BERGER STOQKFLETH.

for preventing the extrusion of the cylin-' ing being provided through which the metal the extrusion openings for inversely changflush with the inner edges of the shell, as and 8. In a die mechanism for forming bearing metal into desired shapes and with de- Signed at Buchanan, this 24 day of Feb

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