US3142115A - Method and apparatus for manufacturing annular workpieces of metal, particularly steel, to be subsequently shaped by cold forging - Google Patents
Method and apparatus for manufacturing annular workpieces of metal, particularly steel, to be subsequently shaped by cold forging Download PDFInfo
- Publication number
- US3142115A US3142115A US122555A US12255561A US3142115A US 3142115 A US3142115 A US 3142115A US 122555 A US122555 A US 122555A US 12255561 A US12255561 A US 12255561A US 3142115 A US3142115 A US 3142115A
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- United States
- Prior art keywords
- blank
- punch
- annular
- die
- metal
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- Expired - Lifetime
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21K—MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
- B21K1/00—Making machine elements
- B21K1/04—Making machine elements ball-races or sliding bearing races
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21K—MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
- B21K1/00—Making machine elements
- B21K1/14—Making machine elements fittings
- B21K1/16—Making machine elements fittings parts of pipe or hose couplings
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
- F16C33/30—Parts of ball or roller bearings
- F16C33/58—Raceways; Race rings
- F16C33/64—Special methods of manufacture
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C19/00—Bearings with rolling contact, for exclusively rotary movement
- F16C19/02—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows
- F16C19/14—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for both radial and axial load
- F16C19/16—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for both radial and axial load with a single row of balls
- F16C19/163—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for both radial and axial load with a single row of balls with angular contact
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49636—Process for making bearing or component thereof
- Y10T29/49643—Rotary bearing
- Y10T29/49679—Anti-friction bearing or component thereof
- Y10T29/49689—Race making
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49789—Obtaining plural product pieces from unitary workpiece
- Y10T29/49796—Coacting pieces
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T83/00—Cutting
- Y10T83/929—Tool or tool with support
- Y10T83/9411—Cutting couple type
- Y10T83/9423—Punching tool
- Y10T83/9425—Tool pair
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T83/00—Cutting
- Y10T83/929—Tool or tool with support
- Y10T83/9411—Cutting couple type
- Y10T83/9423—Punching tool
- Y10T83/9437—Shear-type female tool
Definitions
- This invention relates to a method and apparatus for manufacturing annular workpieces of metal, particularly of steel, which are to be subsequently shaped by cold forging in a press.
- the starting material is a circular disc or a rod section, from which a concentric inner portion is punched out by means of a punch in a die.
- this is achieved in that the diameter difference between the cutting edges of the punch and of the die is about one fourth of the thickness of the blank so that an inclination of about 7 and more results between the two cutting edges in the parting direction; i.e., the radial clearance being about one-eighth of the thickness of the blank.
- the cutting operation will result in a clean cut at the separated work-piece parts (inner part and outer ring).
- the two separated parts of the blank namely, the outer ring and the solid central part, are given such a volume and dimension that they are appropriately pre-shaped for the subsequent shaping.
- a single starting blank may be repeatedly punched as indicated above to form from the resulting solid central portion further annular workpieces for the subsequent forging. This may be suitable, e.g., if the punched annular members are to be used as inner and outer races of anti-friction bearings or are to be combined in a similar unit (screwed pipe coupling or the like).
- the subsequent shaping of the solid central part of the starting blank will result in an optimum utilization of material.
- FIG. 1 is a diagrammatical view showing the punching tool with the inserted blank before the beginning of the punching.
- FIG. 2 is a sectional view showing a pre-shaped blank (pressing).
- FIG. 3 shows the same blank after punching, whereby it has been separated into an outer ring and a solid central part.
- FIG. 4 is a longitudinal sectional view showing the entire punching tool.
- FIG. 5 shows a screwed pipe joint consisting of coldforged annular members.
- FIG. 6 shows an anti-friction bearing consisting of cold-forged annular members.
- FIG. 7 shows a pipe coupling,pthe annular parts of which have bearing shoudlers.
- the starting blank for use in the method according to the invention is a circular disc 1 which is obtained by flatpressing a rod section to exact shape and has the height h.
- This disc is insertedinto an open die 2, the annular shoulder 2 of which serves as a support for the disc.
- the edge 2"' of theannular shoulder formsl a cutting edge.
- the punch 3 engages the top endface of the disc 1.
- the punch has such a diameter d that a cutting clearance s amountingto approximately one-eighthof theheight h of the blank is obtained relative to the die diameter D. With this cutting clearance s, the desc'ent of the punch 3 will result in a cut 4 having an inclination of ab out7 between the parts of the blank 1 to be separated.
- annular member and central part of smaller size may be made from the punched solid central part 1b (FIG. 3) in a subsequent punching operation.
- This separating operation may be repeated as often as the cutting conditions permit.
- This method of manufacture is of advantage if the annular members obtained by punching and having different diameters are combined in a unit of construction (anti-friction bearing, pipe connection and the like). See FIGS. 5, 6 and 7.
- FIG. 4 shows the punching tool after the blank has been separated into the two parts 1a and 1b, both of which are jointly ejected from the die 2 by the ram 5.
- the inclination of the cut between the two parts 1a, 1b is larger than the angle of friction.
- the outer ring 1a is carried along by the central part as the ram 5 rises whereas the separated parts of the blank are not wedged one into the other.
- a method of manufacturing annular workpieces of metal from a solid blank which comprises punching a concentric inner part from said blank by means of a punch and die having a diameter difference which is approximately one fourth of the thickness of said blank so that a cut having an linclination of about 7 is obtained between the cutting edges of the punch and die.
- a method as claimed in claim l which comprises pre-shaping said blank before punching.
- a method of manufacturing assemblies of annular workpieces of metal disposed one in the other which comprises punching a concentric inner part from a solid blank by means of a punch and die having a radius dimension cutting edge clearance which is approximately one-eighth of the thickness of said blank so that a cut having an inclination of about 7 is obtained between the cutting edges of the ⁇ punch and die, to divide said blank into a solid inner member and an annular member, repeating said operation on said solid inner member serving as a blank, cold-forging the annular members thus obtained, and assembling said annular members one in the other.
- a punching tool for manufacturing annular Workthickness which comprises a punch and die adapted to cooperate in punching a cencentric inner part from said blank, said punch and die having a diameter dimension dilerence which is approximately one fourth of said predetermined thickness.
- a punching tool as claimed in claim 6, which comprises a ram disposed opposite to said punch with respect to said die and operable to jointly eject the separated parts of the blank out of the die in the direction toward said punch.
- a punch and die assembly for making annular workpieces from a blank; said punch and die assembly being characterized in that ⁇ the following relationships obtain:
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Forging (AREA)
Description
`Iuly 28, 1964 .scHAMlNG 3,142,115
- ramon AND APPARATUS uANuFAcTu c ANNULAR woRxPIEcEs oF METAL, PARTICULARLY STEEL, BE suBsEQUENTLy SHAPED BY coun FoRGING Filed Ju1y 7, 1961 /Nl/f N OP GUILLAUME SCHAMNG mwa wat 704m ATTORNEYS l bh- United States Patent O METHOD AND APPARATUS FOR MANUFACTUR- ING ANNULAR WORKPIECES OF METAL, PAR- TICULARLY STEEL, TO BE SUBSEQUENTLY SHAPED BY COLD FORGING j Guillaume Schaming, Le Perreux, Seine, France, assignor to Caltexa Trust, Vaduz, Liechtenstein Filed July 7, 1961, Ser. No. 122,555 Claims priority, application Germany July 15, 1960 8 Claims. (Cl. 29-416) This invention relates toa method and apparatus for manufacturing annular workpieces of metal, particularly of steel, which are to be subsequently shaped by cold forging in a press. The starting material is a circular disc or a rod section, from which a concentric inner portion is punched out by means of a punch in a die.
In the manufacture of annular blanks for forgings from rod sections or thick circular discs by punching as indicated above, it has been found in practice that an unclean cut is obtained because burrs, cracks or overlaps tend to form at the surface of cut during punching. These faults in the material are extremely detrimental during the subsequent shaping by cold forging and may lead to rejects. To avoid this disadvantage, it has previously been necessary to machine the unclean cut obtained by punching before performing the cold-forging operation. This machining is an additional operation, which increases the cost of cold-forged workpieces.
It is an object of the invention to improve the punching operation in order to ensure that the punching of a concentric inner part from a rod section or a thick circular disc will result in an absolutely clean cut so that the blank can be readily subjected to subsequent shaping by cold forging, without intermediate machining. According to the invention, this is achieved in that the diameter difference between the cutting edges of the punch and of the die is about one fourth of the thickness of the blank so that an inclination of about 7 and more results between the two cutting edges in the parting direction; i.e., the radial clearance being about one-eighth of the thickness of the blank. With this punch clearance, the cutting operation will result in a clean cut at the separated work-piece parts (inner part and outer ring). The two separated parts of the blank, namely, the outer ring and the solid central part, are given such a volume and dimension that they are appropriately pre-shaped for the subsequent shaping. According to the invention, a single starting blank may be repeatedly punched as indicated above to form from the resulting solid central portion further annular workpieces for the subsequent forging. This may be suitable, e.g., if the punched annular members are to be used as inner and outer races of anti-friction bearings or are to be combined in a similar unit (screwed pipe coupling or the like). The subsequent shaping of the solid central part of the starting blank will result in an optimum utilization of material.
In the accompanying drawing, an illustrative embodiment of the invention is shown.
FIG. 1 is a diagrammatical view showing the punching tool with the inserted blank before the beginning of the punching.
FIG. 2 is a sectional view showing a pre-shaped blank (pressing).
FIG. 3 shows the same blank after punching, whereby it has been separated into an outer ring and a solid central part.
FIG. 4 is a longitudinal sectional view showing the entire punching tool.
FIG. 5 shows a screwed pipe joint consisting of coldforged annular members.
FIG. 6 shows an anti-friction bearing consisting of cold-forged annular members.
ice
FIG. 7 shows a pipe coupling,pthe annular parts of which have bearing shoudlers.
The starting blank for use in the method according to the invention 'is a circular disc 1 which is obtained by flatpressing a rod section to exact shape and has the height h. This discis insertedinto an open die 2, the annular shoulder 2 of which serves as a support for the disc. The edge 2"' of theannular shoulder formsl a cutting edge. The punch 3 engages the top endface of the disc 1. The punch has such a diameter d that a cutting clearance s amountingto approximately one-eighthof theheight h of the blank is obtained relative to the die diameter D. With this cutting clearance s, the desc'ent of the punch 3 will result in a cut 4 having an inclination of ab out7 between the parts of the blank 1 to be separated. These conditions ensure that the separation of the parts of the blank (outer annular member 1a and central portion 1b)-see FIG. 3will result in a satisfactory cut without burr or overlaps so that the separated blank parts can be subsequently shaped to the desired workpiece without intermediate machining. For an economical production it is desirable to separate the blank into two parts having such a volume and size that the blank parts can be readily shaped subsequently to the desired final shape (workpiece). For this purpose, it is recommendable to exactly pre-shape the blank 1, e.g., by trueing it to exact volume and size, e.g., by forming depressions 5, 6 in its end faces, as is shown in FIG. 2.
As has already been indicated, another annular member and central part of smaller size may be made from the punched solid central part 1b (FIG. 3) in a subsequent punching operation. This separating operation may be repeated as often as the cutting conditions permit. This method of manufacture is of advantage if the annular members obtained by punching and having different diameters are combined in a unit of construction (anti-friction bearing, pipe connection and the like). See FIGS. 5, 6 and 7.
FIG. 4 shows the punching tool after the blank has been separated into the two parts 1a and 1b, both of which are jointly ejected from the die 2 by the ram 5. In this case, it is also of advantage that the inclination of the cut between the two parts 1a, 1b is larger than the angle of friction. As a result, the outer ring 1a is carried along by the central part as the ram 5 rises whereas the separated parts of the blank are not wedged one into the other.
What I claim is:
l. A method of manufacturing annular workpieces of metal from a solid blank, which comprises punching a concentric inner part from said blank by means of a punch and die having a diameter difference which is approximately one fourth of the thickness of said blank so that a cut having an linclination of about 7 is obtained between the cutting edges of the punch and die.
2. A method as claimed in claim 1, in which said blank consists of steel.
3. A method as claimed in claim l, which comprises pre-shaping said blank before punching.
4. A method as claimed in claim 1, in which the annular member remaining after punching is subsequently coldforged.
5. A method of manufacturing assemblies of annular workpieces of metal disposed one in the other, which comprises punching a concentric inner part from a solid blank by means of a punch and die having a radius dimension cutting edge clearance which is approximately one-eighth of the thickness of said blank so that a cut having an inclination of about 7 is obtained between the cutting edges of the `punch and die, to divide said blank into a solid inner member and an annular member, repeating said operation on said solid inner member serving as a blank, cold-forging the annular members thus obtained, and assembling said annular members one in the other.
6. A punching tool for manufacturing annular Workthickness, which comprises a punch and die adapted to cooperate in punching a cencentric inner part from said blank, said punch and die having a diameter dimension dilerence which is approximately one fourth of said predetermined thickness. 7. A punching tool as claimed in claim 6, which comprises a ram disposed opposite to said punch with respect to said die and operable to jointly eject the separated parts of the blank out of the die in the direction toward said punch.
8. A punch and die assembly for making annular workpieces from a blank; said punch and die assembly being characterized in that `the following relationships obtain:
where References Cited in the le of this patent UNTED STATES PATENTS 37,189 Westlake Dec. 16, 1862 1,387,638 Bingham Aug. 16, 1921 1,971,083 Schlaa Aug. 2l, 1934 2,383,584 Beishline et al Aug. 28, 1945
Claims (1)
- 5. A METHOD OF MANUFACTURING ASSEMBLIES OF ANNULAR WORKPIECE OF METAL DISPOSED ONE IN THE OTHER, WHICH COMPRISES PUNCHING A CONCENTRIC INNER PART FROM A SOLID BLANK BY MEANS OF A PUNCH AND DIE HAVING A RADIUS DIMENSION CUTTING EDGE CLEARANCE WHICH IS APPROXIMATELY ONE-EIGHT OF THE THICKNESS OF SAID BLANK SO THAT A CUT HAVING AN INCLINATION OF ABOUT 7* IS OBTAINED BETWEEN THE CUTTING EDGES OF THE PUNCH AND DIE TO DIVIDE SAID BLANK INTO A SOLID INNER MEMBER AND AN ANNULAR MEMBER, REPEATING SAID OPERATION ON SAID SOLID INNER MEMBER SERVING AS A BLANK, COLD-FORGING THE ANNULAR MEMBERS THUS OBTAINED, AND ASSEMBLING SAID ANNULAR MEMBERS ONE IN THE OTHER.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE3142115X | 1960-07-15 |
Publications (1)
Publication Number | Publication Date |
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US3142115A true US3142115A (en) | 1964-07-28 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US122555A Expired - Lifetime US3142115A (en) | 1960-07-15 | 1961-07-07 | Method and apparatus for manufacturing annular workpieces of metal, particularly steel, to be subsequently shaped by cold forging |
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3233307A (en) * | 1961-12-13 | 1966-02-08 | Skf Svenska Kullagerfab Ab | Method of producing a pair of rings from a substantially circular blank |
US4516450A (en) * | 1983-03-07 | 1985-05-14 | Wilson Tool Company | Slug-retaining die |
US7895873B1 (en) * | 2008-04-23 | 2011-03-01 | Meadville Forging Co LP | Method and system for simultaneously forging two parts |
US20190024710A1 (en) * | 2015-06-12 | 2019-01-24 | Schaeffler Technologies AG & Co. KG | Angular contact ball bearing having a cold-formed bearing ring, and a method for manufacturing a bearing ring of said angular contact ball bearing |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US37189A (en) * | 1862-12-16 | Improved mode of punching countersunk holes | ||
US1387638A (en) * | 1917-07-16 | 1921-08-16 | Bock Bearing Company | Process of making cup and cone members for roller-bearings |
US1971083A (en) * | 1930-11-29 | 1934-08-21 | Schlaa Friedrich Im | Production of ball races and the like |
US2383584A (en) * | 1941-01-21 | 1945-08-28 | American Car & Foundry Co | Method of flanging bimetallic plate |
-
1961
- 1961-07-07 US US122555A patent/US3142115A/en not_active Expired - Lifetime
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US37189A (en) * | 1862-12-16 | Improved mode of punching countersunk holes | ||
US1387638A (en) * | 1917-07-16 | 1921-08-16 | Bock Bearing Company | Process of making cup and cone members for roller-bearings |
US1971083A (en) * | 1930-11-29 | 1934-08-21 | Schlaa Friedrich Im | Production of ball races and the like |
US2383584A (en) * | 1941-01-21 | 1945-08-28 | American Car & Foundry Co | Method of flanging bimetallic plate |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3233307A (en) * | 1961-12-13 | 1966-02-08 | Skf Svenska Kullagerfab Ab | Method of producing a pair of rings from a substantially circular blank |
US4516450A (en) * | 1983-03-07 | 1985-05-14 | Wilson Tool Company | Slug-retaining die |
US7895873B1 (en) * | 2008-04-23 | 2011-03-01 | Meadville Forging Co LP | Method and system for simultaneously forging two parts |
US20190024710A1 (en) * | 2015-06-12 | 2019-01-24 | Schaeffler Technologies AG & Co. KG | Angular contact ball bearing having a cold-formed bearing ring, and a method for manufacturing a bearing ring of said angular contact ball bearing |
US10465744B2 (en) * | 2015-06-12 | 2019-11-05 | Scjaeffer Technologies AG & Co. KG | Angular contact ball bearing having a cold-formed bearing ring, and a method for manufacturing a bearing ring of said angular contact ball bearing |
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