US1486587A - Means for and method of drop-forging crank shafts - Google Patents

Description

March 11,1924, 1,486,587

H. H. KEEPORTS MEANS FOR AND METHOD OF DROP FORGING CRANK SHAFTS Filed May 17, 1919 3 Sheets$heet l Qttmncq March 11 1924. 1,486,587 H. H. KEEPORTS I MEANS FOR AND METHOD OF DROP FORGING CRANK SHAFTS Filed May 17, 1919 3 Sheets-Sheet 2 an uenfoz March 11 1924. 1,48%,587

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' HARRY H. EPORTS, OF DETROIT, MICHIGAN.

MS FOR AND .METHOD OF DROP-FORGING CRANK SHAFTS.

Application filed may 17, 1919. Serial Ito. 297 848.

To all whom it may concern.

Be it known that I, HARRY I-I. KEEPoRTs, -a citizen of the United States, residing at Detroit, in the county of Wayne and State e of Michigamhave invented certain new and useful Improvements in Means for and Methods of Drop-Forging Crank Shafts, of which the following is a specification.

This invention relates to improved means it or dies for dropforging crank shafts and tlfiefrpethod or process of forming the crank s a The objects of the invention are to pro- I vide improved methods of forming crank shafts and whereby the structure of the metal will not be strained by the twisting after forgin and to improve the process.

Objects which relate to mere details will appear from the description to follow.

The objects of this invention are accomplished by the devices and means described in the following specification. The invention is defined and pointed out in the claims.

I A structure, which is a preferred embodi- 26 ment of the invention is clearly illustrated in the accompanying drawings forming a part of this specification, in which:'

Fig. I is a plan view of the dies for drop forging the crank shaft.

Fig. II is an elevation of the dies somew at separated looking against the lower si e of Fi I. I

Fig. III is a vertical detail sectional view of the dieswith a; completely forged crank shaft disposed therein, the same being taken on a line corresponding to line 33 of Figs. I, IV and VI, arts of the crank throws being by dotted ines.

Fig. IV is a transverse detail sectional view taken on line corresponding to line 4-4 of Fig. III, the position of art of the prank throws being indicated by dotted mes.

Fig. V' is an enlarged fragmentary -detail view artially in section on line 5-5 of Figs. II and VI, of the integral forming projection 3 of the bottom die.

' Fig. VI is a detail view of the operating faces of the bottom and top dies 1 and 2 placed side by side.

Fig. VII is an illustration of the billet from which the crank shaft is formed.

Fig. VIII is a plan view of the same after the first bending operation performed by the die.

Fig. IX is an elevation View of the crank shaft after such preliminary bending operation.

Fig. X is a plan view of the crank shaft after the final operation of the forming dies before the fin or flash has been trimmed 0d.

Fi XI is a perspective view of the complete y formed crank shaft ready for machining.

Fig. XII is an end elevation view of this complete crank shaft.

In the drawing, similar numerals of reference refer to similar parts throughout the several views.

Considering the numbered parts of the drawing, the bottom die 1 is formed with double impressions, one at the edge for the preliminary bending of the crank shaft in a vertical plane in which are upward projections 3, 3 for deflecting portions of the shaft laterally at each side of the center and with depressions 4, 4: for the centrally dis posed throws of the crank shaft. orresponding depressions 5, 5 to the rojections 3, 3 are in the upper die dispose at an angle and projections 6, 6' are on the upper die corresponding to the depressions at, I in the lower die.

The projections 3, 3 are disposed at an angle to compensate or allow for the bending of the blank in the second impression and their upper surfaces are curved as indicated in Fig. V, the diagonal relation appearing in Fig. VI. This permits the bending of the 'metal without undue strain at these points and conforms the part at this preliminary bend so that it will be correctly and readily deflected when the partially bent shaft is passed to the second die recess.

The second recess in the die is provided with deep end cavities 7, 7 in the bottom die for receiving the end throws of the crank, as clearly appears in Fig. III. Corresponding pro ections 8, '8' on the upper die 1 coact therewith. Recesses 9, 9 are disposed laterally adjacent to these end cavities as will be seen by referring to the dotted lines in Fig. III and the full lines in the dies 1 and 2 of Fig. VI. The precise angle of the same to the bottom cavity appears by the dotted lines in Fig. IV. The

central throws of the crank are formed by the laterally disposed recesses 10, 10' on the opposite side, as will be seen by the transverse sectional view shown in Fig. IV and the plan view in Fig. VI. These recesses coact with recesses 11, 11 and 12, 12 in the top die respectively.

The straight billet 13 is first operated upon by the preliminary bending as seen in Figs. VIII and IX on the first or edge recesses of the dies. The central crank throws 15, 15 are struck down into the cavities 4:, 4: by the projections 6, 6 and the next adjacent crank throws 14, 14: are struck up by the projections 3, 3 into the cavities 5, 5, see Figs. II and VI, the projections 3 being disposed at an angle for the preliminary bend so that the crank throws are properly deflected.

After the preliminary bending is completed, as seen in Figs. VIII and IX, the partially bent crank shaft is placed in the second recess with the central throws 14, 14, 15, 15' in a horizontal plane where the end crank throws 16, 16' are formed by the metal being forced into the recesses 7, 7 of the bottom die 2 by the projections 8, 8 on the upper dies and at the same time the dies coact to forge and forcethe shaft journals down and the crank throws 14, 14 into the lateral recesses 9, 9' throu h an angle of 30 degrees and the crank tirows 15, 15 into the recesses 10, 10. The drop hammer is operated sufficiently to completely form the crank shaft with the usual projecting fin or flash. The fin or flash is then cut off and the crank shaft returned to the die and trued up.

A plan view of the completed crank shaft appears in Fig. X. The crank shaft with the fin cut ofi appears in perspective in Fig. XI, and the relation of the crank throws appears in the end elevation view -Fi XII. The form of the dies and their relation appear in Fig. IV the exact parting of the dies only appear in'connection with Fig. II or Fig. VI and the complete crank shaft appearing in Fig. X.

While this mvention is shown as applicable to a six throw crank shaft, it is very clear that it is adaptable to three or any multi le of three and indeed can be made use 0 for any crank shaft having more than a double throw. However, three or multiples of three lend themselves best to this method because that only calls for a deflecting of certain of the crank throws through an angle of 30 degrees so that each lateral crank throw stands at an angle of degrees from the perpendicular, which is very readily accomplished in the drop hammer.

I illustrate an apparatus adapted to the forming of the intermediate crank throws first and the end throws last, which has cerinsane? tain advantages and which I desire to claim specifically. I, however, call attention to the fact that the dies can be so shaped and their recesses so located that the throws 1 and 6 may be deflected down, or possibly up in the second operation, or 2 and 5, or 3 and 4,v where a six throw crank shaft is being forged.

I have shown the and which I desire to claim specifically. I also desire to claim the same broadly.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a means for formin crank shafts, the combination of a die with impressions comprising recesses in which are projections for forming preliminary vertical -bends to form intermediate crank throws,

the end projections of which are inclined and disposed at an angle to the axial line thereof to give the initial lateral impulse to the corresponding crank throw, a second impression for completing the operation containing deep vertical recesses to form the end crank throws, and lateral recesses to receive and deflect the intermediate crank throws after the first bend, 'coacting for the purpose specified.

2. In a means for forming crank shafts, the combination of a die with impressions comprising recesses in which are projections for forming preliminary central vertical bends to form the throws, and a second impression for completing the operation containing dee vertical end recesses to form the end tfirows, and lateral recesses to receive and deflect the central crank throws after the first bend coacting for the purpose specified.

3. In a means for forming shafts, the combination of a die with impressions comprising recesses in which are projections for forming preliminary vertical bends to form opposite and adjacent crank shaft throws, a second impression for completing the operation containing deep vertical recesses to form additional crank shaft throws, and lateral recesses to receive and deflect.v the first formed throws after the first bend, coacting for the purpose specified.

4. The method of forming a crank shaft consisting in bending the shaft preliminarily in substantially a vertical plane to form the central portion of the crank throws, and thereafter bending the additional end crank throws at substantially a right angle to the plane of the first formed throws and deflecting the first formed throws into oblique planes in'the same operation.

5. The method of forming a crank shaft consisting in bending the shaft preliminarily insubstantially a vertical plane to form the central crank throws, and thereform preferred by meintermediate crank means? after forming additional crank throws in a plane at substantially ri ht angles to the plane oi the first crank t rows and deflecting the first formed throws into oblique planes.

6. The method of forming a six throw crank shaft consisting in a reliminary bend of the central four throws in the same plane, two to one side of the axial line and two to the opposite side, and thereafter bending the end crank throws in a plane at substantially right angles to the first throws, and deflecting the said first throws to oblique planes at angles of 60 degrees to the first plane, as specified.

7. The method of forging crank shafts consisting in first bending the intermediate crank throws, and then bending and forming the end throws while-at the same time deflecting the intermediate throws to ob- 8. The method of forming crank shafts consisting in first bending in a vertical plane opposed central crank throws and then bending and forming additional end crank throws in a plane at right angles to the plane of the first formed crank throws and deflecting the first formed crank throws to oblique planes of the required angle, as specified.

In witness whereof, I have hereunto set my hand and seal in the presence of two witnesses.

HARRY H. KEEPORTS. [12. s.]

Witnesses:

FRANK CUR'rIs Moran, STEPHEN J. PYLES.

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