US3735619A - Gear roll chamfering - Google Patents

Gear roll chamfering Download PDF

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Publication number
US3735619A
US3735619A US00221357A US3735619DA US3735619A US 3735619 A US3735619 A US 3735619A US 00221357 A US00221357 A US 00221357A US 3735619D A US3735619D A US 3735619DA US 3735619 A US3735619 A US 3735619A
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United States
Prior art keywords
gear
teeth
die
chamfering
rolling
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US00221357A
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English (en)
Inventor
R Tersch
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nachi Machining Technology Co
Original Assignee
Lear Siegler Inc
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Filing date
Publication date
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Publication of US3735619A publication Critical patent/US3735619A/en
Assigned to ADD, INC., A MICHIGAN CORP. reassignment ADD, INC., A MICHIGAN CORP. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: LEAR SIEGLER, INC. A DE. CORP.
Assigned to NATIONAL BROACH & MACHINE COMPANY, reassignment NATIONAL BROACH & MACHINE COMPANY, CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). 5-30-86 Assignors: ADD, INC.
Assigned to FERRETT, JAMES A., RAO, SURENDRA B., WILKINS, LEONARD J., DONNELLY, JOHN T.; reassignment FERRETT, JAMES A. SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: NATIONAL BROACH & MACHINE COMPANY
Assigned to MIDLANTIC NATIONAL BANK reassignment MIDLANTIC NATIONAL BANK SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: NATIONAL BROACH & MACHINE COMPANY
Anticipated expiration legal-status Critical
Assigned to IMEC CORPORATION, A CORP. OF MA, NATIONAL BROACH & MACHINE COMPANY, 17500 TWENTY-THREE MILE RD., MT. CLEMENS, MI 48044 A CORP. OF MI reassignment IMEC CORPORATION, A CORP. OF MA RELEASED BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). 12-21-90 CA Assignors: MIDLANTIC NATIONAL BANK, PS HOLDING CORPORATION, A CORP. OF CA
Assigned to NATIONAL BROACH & MACHINE COMPANY reassignment NATIONAL BROACH & MACHINE COMPANY ASSIGNMENT OF ASSIGNORS INTEREST. SECURITY AGREEMENT RECORDED AT REEL 5033 FRAME 0527 Assignors: DONNELLY, JOHN T., FERRETT, JAMES A., RAO, SURENDRA B., WILKINS, LEONARD J.
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21H—MAKING PARTICULAR METAL OBJECTS BY ROLLING, e.g. SCREWS, WHEELS, RINGS, BARRELS, BALLS
    • B21H5/00—Making gear wheels, racks, spline shafts or worms
    • B21H5/02—Making gear wheels, racks, spline shafts or worms with cylindrical outline, e.g. by means of die rolls
    • B21H5/022—Finishing gear teeth with cylindrical outline, e.g. burnishing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23F—MAKING GEARS OR TOOTHED RACKS
    • B23F19/00—Finishing gear teeth by other tools than those used for manufacturing gear teeth
    • B23F19/10—Chamfering the end edges of gear teeth
    • 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
    • Y10T29/49462—Gear making
    • Y10T29/49467—Gear shaping
    • Y10T29/49471—Roll forming
    • 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
    • Y10T409/00—Gear cutting, milling, or planing
    • Y10T409/10—Gear cutting
    • Y10T409/101113—Gear chamfering or deburring
    • Y10T409/101272—Using relatively reciprocating or oscillating cutter

Definitions

  • ABSTRACT Helical gears are rolled to improve tooth surfaces and in the same operation have the acute end corners of the teeth chamfered. The chamfering precedes finish rolling so as to avoid displacement of metal above the tooth profile.
  • a gear rolling apparatus preferably employing a single gear-like die, in which means are provided for effecting relative radial or depth feed between the die and the gear in order to establish rolling pressure between the teeth of the die and the gear.
  • means are provided for effecting a relative traverse between the die and gear in a plane parallel to the axes of both the die and gear. Conveniently, this relative traverse may be in a direction parallel to the axisof the gear.
  • a pair of chamfering dies Associated with the die, which is generally conjugate to the desired form of teeth on the work gear, are a pair of chamfering dies the profile curvature of the teeth being the same as that of the gear rolling die but the teeth being tapered, or having one side inclined as in Paulger U.S. Pat. No. 3,233,518, so that as the work gear is moved axially to force the ends of its teeth into the tapered tooth spaces of the chamfering die, the
  • acute corners are chamfered.
  • the tooth surfaces of the chamfering dies adjacent the obtuse corners are continuations of the sides of the teeth of the rolling die.
  • the taper may be differently arranged so that if desired, the obtuse corners might be chamfered, or in some cases, a spur gear could be provided with a mild chamfer at all four corners of each tooth thereof.
  • FIG. 1 is an elevational view of a machine employed in practice of the present invention.
  • FIG. 2 is an enlarged view of the assembly of rolling and tapered dies.
  • FIG. 3 is a fragmentary elevational view on the line 3-3, FIG. 2.
  • FIG. 4 is a much enlarged composite showing of the die assembly showing its operation on adjacent teeth of a work gear.
  • FIG. 1 there is shown a gear rolling machine comprising a frame having a forwardly-projecting portion 12 carrying a rotatable gear rolling. die 14. Suitable means (not shown) are provided for driving the die in rotation.
  • a forwardly projecting base portion 16 carrying a support 22 which is vertically adjustable by threaded adjusting means indicated generally at 24.
  • a slide 26 which is connected to the support 22 by toggle mechanism indicated generally at 28 and adapted to be rocked by suitable means such for example as a hydraulic piston and cylinder device diagrammatically indicated at 30, to bring the intermediate pivot 32 of the toggle device into vertical alignment with a lower pivot 34 provided on the upper end of the support 22, and an upper pivot 36 provided at the interior of the vertically movable slide 26.
  • the vertically movable slide 26 carries a sub-table 40, herein shown as angularly adjustable about a vertical axis and provided at its upper end with rectilinear ways indicated at 42, which carries an upper table 44 for horizontal movement along the ways 42.
  • Means are provided for effecting horizontal traverse of the upper table 44 and this means is indicated as a nut 46 carried by the sub-table 40, and a feed screw 48 carried by the upper table 44 and in threaded engagement with the nut.
  • Suitable means such as a worm 50 and worm gear 52 are provided for effecting rotation of the feed screw, the worm 50 being driven by a motor indicated at 54 carried by a bracket 56 mounted on the upper table 44.
  • a crowning table 60 is mounted on a pivot connection 62 intermediate the upper table 44 and the crowning table 60, and suitable cam means (not shown) may be provided for effecting rocking of the crowning table 60 in accordance with traverse thereof as effected by the feed screw 48.
  • suitable means may be provided for rocking the crowning table 60 without traverse of the upper table 44 to accomplish substantially horizontal movement of a work gear W, as will subsequently be described.
  • suitable adjustable abutment means are provided in- .termediate the crowning table and the upper table 44.
  • a die assembly as best illustrated in FIG. 2 is provided.
  • the die support arbor is indicated at and includes an intermediate enlarged portion on which is provided an adapter 72 having a cylindrical flange 74 at one end.
  • the adapter 72 is keyed to the arbor 70 by the key 76.
  • Each chamfering die 80 includes a toothed portion 82 and a reduced cylindrical portion 84.
  • the teeth of the chamfering dies are in substantial alignment with the teeth of the gear rolling die but are tapered in such a way as to engage end surfaces of the teeth of a work gear moved axially to bring the ends of its teeth into the converging tooth spaces of the chamfering dies.
  • Suitable means such for example as a pin 86, is provided to couple the flange 74 of the adapter to the left hand chamfering die 80 as seen in FIG. 2.
  • Rotation of the left hand chamfering die is transmitted to the gear rolling die by means of circumferential adjusting and driving means including a pin 90, details of which are best illustrated in FIG. 3, in conjunction with FIG. 2.
  • the pin 90 extends through an opening in the gear rolling die 14 and into enlarged openings 92 in the chamfering dies 80.
  • Adjustment screws 94 are provided in openings 96 in the chamfering dies. As one of the screws 94 is retracted the other may be advanced to effect angular adjustment between the chamfering dies and the gear rolling die. In addition to providing for angular adjustment, it will of course be apparent that the pin 90 and the screws 94 constitute driving connections so that the left hand chamfering die 80 drives the rolling die 14, which in turn drives the right hand chamfering die 80, as seen in FIG. 2.
  • the teeth of the gear rolling die 14 are indicated at 100 and the teeth of the chamfering dies 80 are indicated at 102.
  • the tooth surfaces 104 of the gear rolling die are longitudinally concave so that in the final rolling operation the teeth of the gear may be longitudinally convex or crowned, although this is not a part of the present invention.
  • Portions of the gear teeth cooperating with the die teeth 100 and 102 are indicated at 106 and 108, and in FIG. 4 it will be observed that the teeth of the gear are helical and that the end corners of the teeth at one side of the gear are obtuse as indicated at 110 while the other end corners 112 of the teeth at the same side are acute.
  • the teeth of the chamfering die are provided with surfaces 116 which are continuations of the surfaces 104 of the teeth of the gear die except of course for the special concavity of these teeth indicated at 104, which may or may not be provided.
  • the surfaces 116 of the teeth 102 of the chamfering die are shown as extending at the same helix angle as the teeth of the gear W.
  • the teeth 102 are tapered so that the opposite side of the teeth of the chamfering die as indicated at 118, extend at an angle to the sides 116, and in FIG. 4 the surfaces 118 are indicated as extending generally parallel to the axes of the gear and dies, or perpendicular to the planes thereof.
  • the surfaces 118 may be considered as surfaces of a conventional spur gear tooth.
  • the chamfering operation while it is effective to produce the chamfered surface 114 and to displace material beyond the ends of the teeth as indicated at 124, may in some cases displace a minor amount of metal into the operating surface of the tooth.
  • any protuberance thus caused of material beyond the desired tooth profile is eliminated by the subsequent rolling operation in which the work gear is fed into the die until the tooth surfaces are roll finished, as is well understood in the art.
  • rocking table 60 as means for effecting substantially axial movement of the gear W into engagement with the chamfering dies. This will eliminate the necessity of providing the feed screw 48 and associated mechanism. Minor rocking movement of the crowning table 60 from the intermediate horizontal position will be sufficient to bring the ends of the teeth of the gear into engagement with the tapered chamfering dies, particularly if the width of the gear rolling die is only slightly greater than the width of the gear.
  • the method may be carried out with the work gear in tight mesh with the tooth rolling die, and this tends to minimize displacement of material above the profiled surface of teeth, or the chamfering operation may be carried out with the gear and tooth rolling die in mesh but with appreciable back-lash or clearance.
  • the method of roll finishing and chamfering gears which comprises providing a die assembly of a gear rolling die having teeth substantially conjugate to the desired form to be produced on the teeth of a work gear, and achamfering die directly adjacent one side of the rolling 'die and having teeth in end alignment with and forming continuations of the teeth of the rolling die, one side of the chamfering teeth being angularly disposed to the corresponding side of the teeth of the gear rolling die to intercept the adjacent corners of gear teeth, meshing the teeth of the gear with the teeth of the rolling die near to at least substantially full depth, driving the die assembly and gear in rotation, relatively traversing the gear and die assembly in a plane parallel to the axes of both to force the ends of the teeth at one side of the gear into the tooth spaces of the chamfering die to chamfer end corners thereof, reversing traverse to bring the teeth of the gear into registration only with the teeth of the rolling die, providing a relatively depth feed between the gear and die assembly to roll finish the teeth of the gear from end to end and to

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Gear Processing (AREA)
  • Gears, Cams (AREA)
US00221357A 1972-01-27 1972-01-27 Gear roll chamfering Expired - Lifetime US3735619A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US22135772A 1972-01-27 1972-01-27

Publications (1)

Publication Number Publication Date
US3735619A true US3735619A (en) 1973-05-29

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US00221357A Expired - Lifetime US3735619A (en) 1972-01-27 1972-01-27 Gear roll chamfering

Country Status (7)

Country Link
US (1) US3735619A (fr)
JP (1) JPS55141B2 (fr)
CA (1) CA964498A (fr)
DE (1) DE2303597A1 (fr)
FR (1) FR2169339B1 (fr)
GB (1) GB1386043A (fr)
IT (1) IT977024B (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3894418A (en) * 1973-03-29 1975-07-15 Zahnradfabrik Friedrichshafen Apparatus for finishing gear teeth
US4290718A (en) * 1977-05-03 1981-09-22 Samputensili S.P.A. Tools for bevelling and deburring gears
DE4130927C1 (en) * 1991-09-18 1992-06-17 Praewema Werkzeugmaschinenfabrik Gmbh, 3440 Eschwege, De Chaser gear for gear tooth deburring and edging - has part of its teeth with compression flanks, engaging angular edges of worked gear teeth
EP1043113A1 (fr) * 1999-04-09 2000-10-11 Samputensili S.p.A. Procédé pour le chanfreinage et l'ébavurage des dents d'une roue dentée, dispositif pour la mise en oeuvre de ce procédé, et outil correspondant
US20050039575A1 (en) * 2003-07-22 2005-02-24 Nissan Motor Co., Ltd. Sintered sprocket for silent chain and production method therefor
WO2021156355A1 (fr) * 2020-02-07 2021-08-12 Profiroll Technologies Gmbh Outil de laminage et procédé de laminage d'un profilé

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2225244B1 (fr) * 1973-04-14 1978-01-06 Hurth Masch Zahnrad Carl
GB2046645B (en) * 1979-02-08 1983-04-20 Hurth Verwaltungs Gmbh Apparatus and method for chipforming deburring or chamfering of the end face tooth edges of gear wheels
JPS57123476U (fr) * 1981-01-26 1982-07-31
JPS60197316A (ja) * 1984-03-21 1985-10-05 Yutaka Seimitsu Kogyo Kk 円筒歯車用転圧面取り工具
FR2646419B1 (fr) * 1989-04-28 1991-09-27 Rhone Poulenc Chimie Procede de preparation d'acides hexenedioiques-1,6
US10570649B2 (en) 2017-08-17 2020-02-25 Gecom Corporation Door lock apparatus

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2206450A (en) * 1935-04-10 1940-07-02 Packard Motor Car Co Apparatus for forming gears
GB698122A (en) * 1951-01-13 1953-10-07 Morris Commercial Cars Ltd Improvements relating to helical gears
US3233518A (en) * 1963-12-05 1966-02-08 Nat Broach & Mach Method and apparatus for chamfering gear teeth

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH539484A (de) * 1970-05-12 1973-07-31 Zahnradfabrik Friedrichshafen Einrichtung zum Einwalzen von Stirnkanten von vorverzahnten Zahnrädern

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2206450A (en) * 1935-04-10 1940-07-02 Packard Motor Car Co Apparatus for forming gears
GB698122A (en) * 1951-01-13 1953-10-07 Morris Commercial Cars Ltd Improvements relating to helical gears
US3233518A (en) * 1963-12-05 1966-02-08 Nat Broach & Mach Method and apparatus for chamfering gear teeth

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3894418A (en) * 1973-03-29 1975-07-15 Zahnradfabrik Friedrichshafen Apparatus for finishing gear teeth
US4290718A (en) * 1977-05-03 1981-09-22 Samputensili S.P.A. Tools for bevelling and deburring gears
DE4130927C1 (en) * 1991-09-18 1992-06-17 Praewema Werkzeugmaschinenfabrik Gmbh, 3440 Eschwege, De Chaser gear for gear tooth deburring and edging - has part of its teeth with compression flanks, engaging angular edges of worked gear teeth
EP1043113A1 (fr) * 1999-04-09 2000-10-11 Samputensili S.p.A. Procédé pour le chanfreinage et l'ébavurage des dents d'une roue dentée, dispositif pour la mise en oeuvre de ce procédé, et outil correspondant
US6571475B1 (en) 1999-04-09 2003-06-03 Samputensili S.P.A. Method of chamfering and deburring gear teeth, device implementing such a method, and relative tool
US20050039575A1 (en) * 2003-07-22 2005-02-24 Nissan Motor Co., Ltd. Sintered sprocket for silent chain and production method therefor
US7041149B2 (en) * 2003-07-22 2006-05-09 Nissan Motor Co., Ltd. Sintered sprocket for silent chain and production method therefor
WO2021156355A1 (fr) * 2020-02-07 2021-08-12 Profiroll Technologies Gmbh Outil de laminage et procédé de laminage d'un profilé

Also Published As

Publication number Publication date
GB1386043A (en) 1975-03-05
JPS55141B2 (fr) 1980-01-05
DE2303597A1 (de) 1973-08-02
IT977024B (it) 1974-09-10
CA964498A (en) 1975-03-18
JPS4884069A (fr) 1973-11-08
FR2169339A1 (fr) 1973-09-07
FR2169339B1 (fr) 1977-10-28

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AS Assignment

Owner name: ADD, INC., A MICHIGAN CORP.,STATELESS

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:LEAR SIEGLER, INC. A DE. CORP.;REEL/FRAME:004600/0061

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Free format text: ASSIGNMENT OF ASSIGNORS INTEREST. SECURITY AGREEMENT RECORDED AT REEL 5033 FRAME 0527;ASSIGNORS:DONNELLY, JOHN T.;WILKINS, LEONARD J.;FERRETT, JAMES A.;AND OTHERS;REEL/FRAME:005639/0406

Effective date: 19910312