1、AN AMERICAN NATIONAL STANDARDASME B5.50-2009Revision of ASME B5.50-1994 (R2003)7/24 Taper Tool to Spindle Connection for Automatic Tool ChangeASME B5.50-2009Revision of ASME B5.50-1994 (R2003)7/24 Taper Tool toSpindle Connectionfor Automatic ToolChangeAN AMERICAN NATIONAL STANDARDDate of Issuance: D
2、ecember 11, 2009This Standard will be revised when the Society approves the issuance of a new edition. There willbe no addenda or written interpretations of the requirements of this Standard issued to this edition.Periodically, certain actions of the ASME B5 Committee may be published as Cases. Case
3、s arepublished on the ASME Web site under the Committee Pages at http:/cstools.asme.org as they areissued.ASME is the registered trademark of The American Society of Mechanical Engineers.This code or standard was developed under procedures accredited as meeting the criteria for American NationalStan
4、dards. The Standards Committee that approved the code or standard was balanced to assure that individuals fromcompetent and concerned interests have had an opportunity to participate. The proposed code or standard was madeavailable for public review and comment that provides an opportunity for addit
5、ional public input from industry, academia,regulatory agencies, and the public-at-large.ASME does not “approve,” “rate,” or “endorse” any item, construction, proprietary device, or activity.ASME does not take any position with respect to the validity of any patent rights asserted in connection with
6、anyitems mentioned in this document, and does not undertake to insure anyone utilizing a standard against liability forinfringement of any applicable letters patent, nor assume any such liability. Users of a code or standard are expresslyadvised that determination of the validity of any such patent
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8、 those interpretations of this document issued in accordance with the establishedASME procedures and policies, which precludes the issuance of interpretations by individuals.No part of this document may be reproduced in any form,in an electronic retrieval system or otherwise,without the prior writte
9、n permission of the publisher.The American Society of Mechanical EngineersThree Park Avenue, New York, NY 10016-5990Copyright 2009 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.CONTENTSForeword ivCommittee Roster . vCorrespondence With the B5 Committee vi1 General
10、. 12 Essential Dimensions for 7/24 Taper Toolholder Shank 23 Essential Dimensions for Retention Knobs 24 Essential Dimensions for 7/24 Taper Spindle Sockets . 2Figure1 Optional Face-Mount Holes, 7/24 Taper Spindle Socket . 2Tables1 Essential Dimensions of Basic Toolholder Shanks for Machining Center
11、s WithAutomatic Tool Changers 32 Essential Dimensions of Retention Knobs . 53 Essential Dimensions of 7/24 Taper Spindle Socket . 7Nonmandatory AppendicesA Useful Technical Information . 9B Excerpt From ISO 1947:1973, System of Cone Tolerances for Conical WorkpiecesFrom C p 1:3 to 1:500 and Lengths
12、From 6 to 630 mm . 11iiiFOREWORDThe Aerospace Industries Association (AIA) developed, in cooperation with machine toolbuilders and users, standards of toolholder shanks and retention knobs for machining centerswith automatic tool changers. AIA/NAS 970 was first published in 1964. The objective of th
13、isstandardization effort was to reduce the large number of already existing tool shank configurationsand to prevent the creation of new ones. The toolholder shanks made by different machine toolbuilders varied in the methods and in dimensional details of the gripping by the transfer mecha-nism and r
14、etention in the machine tool spindle. The resulting lack of interchangeability createdproblems of maintaining large toolholder inventories. The AIA standard covered a series ofstraight and tapered shank toolholders, but the standard never found wide acceptance; one ofthe reasons given for this was t
15、hat standardization attempted too “early in the art” would havestifled innovation and development of better tool shanks for machining centers.During the intervening years, almost every machine tool builder continued to develop theirown, often proprietary and very ingenious, toolholder shank configur
16、ations for their machiningcenters. This resulted in an almost unbearable economic situation, where one user had to maintainno less than 28 noninterchangeable tool shank configurations to operate their machining centers,supplied by the various machine tool builders. These 28 different tool shank conf
17、igurations shouldbe multiplied by the number of basic sizes to get an understanding of the resulting tool inventoryproblem.A major user of machining centers decided to end this situation and developed a tool shankfor machining centers. Several major machine tool builders, toolholder manufacturers, a
18、nd usersof machining centers were approached to discuss and confirm the need and practicality of theirproposed design, and consider it as a basis for an American National Standard. A technicalcommittee (TC 45) of American National Standards Committee (ANSC) B5, Group C, was dele-gated to study the p
19、roposed tool shank and prepare drafts for an American National Standard.A standard was developed and published in November of 1978, as ANSI B5.50-1978. Thetechnical committee followed the policy to establish new standards in SI units, and it was hopedthat ISO would adopt a common worldwide metric st
20、andard.After a number of meetings and recommendations, the ISO put forward a recommendationthat would create more than one standard, which would lead to confusion by the addition of anumber of national metric standards.TC 45 of ANSC B5, Group C therefore recommended that the 1978 edition of the stan
21、dard berevised and replaced with a new inch standard to reflect usage in this country.This Standard specifies the dimensions of toolholder shanks, retention knobs, and sockets, anduseful related technical information for machine tool spindles having 7/24 tapers intended forautomatic tool changing.Di
22、mension M (Table 1) has been revised to allow for greater manufacturing flexibility.Prior to this Standard, there were no applicable standards specifying dimensions and tolerancesfor tool sockets to match the tool shanks in ASME B5.50-1994.Suggestions for improvement of this Standard are welcome. Th
23、ey should be sent to TheAmerican Society of Mechanical Engineers, Secretary, B5 Standards Committee, Three ParkAvenue, New York, NY 10016-5990.This revision was approved as an American National Standard on March 31, 2009.ivASME B5 COMMITTEEMachine Tools Components, Elements,Performance, and Equipmen
24、t(The following is the roster of the Committee at the time of approval of this Standard.)STANDARDS COMMITTEE OFFICERSC. T. Wax, ChairC. J. Gomez, SecretarySTANDARDS COMMITTEE PERSONNELJ. A. Babinski, Contributing Member, Danaher MotionA. M. Bratkovich, The Association for Manufacturing TechnologyJ.
25、B. Bryan, Honorary Member, ConsultantH. Cooper, Honorary Member, ConsultantD. A. Felinski, The Association for Manufacturing TechnologyC. J. Gomez, The American Society of Mechanical EngineersK. J. Koroncey, General MotorsC. D. Lovett, ConsultantD. Mancini, Edmunds GagesJ. A. Soons, National Institu
26、te of Standards and TechnologyR. C. Spooner, Powerhold, Inc.D. Springhorn, Diebold Goldring Tooling, USAC. T. Wax, ConsultantTECHNICAL COMMITTEE 45 SPINDLE NOSES ANDTOOL SHANKS FOR MACHINING CENTERSD. Springhorn, Chair, Diebold Goldring Tooling, USAJ. Burley, Vice Chair, BIG Kaiser Precision Tool, I
27、nc.D. W. Berling, OdawaraD. G. Hartman, Parlec, Inc.G. S. Hobbs, Advanced Machine and Engineering Co.K. Hoffmann, Ingersoll Machine ToolsC. Koehn, Stotz USAR. Laube, Hydra-Lock Corp.D. Mancini, Edmunds GagesE. I. Rivin, Wayne State UniversityO. Sandkuehler, Bilz Tool Co., Inc.S. G. Wallace, The Boei
28、ng Co.C. T. Wax, ConsultantH. M. Whalley, The George Whalley Co.C. Xie, Centrix Precision, Inc.vCORRESPONDENCE WITH THE B5 COMMITTEEGeneral. ASME standards are developed and maintained with the intent to represent theconsensus of concerned interests. As such, users of this Standard may interact with
29、 the Committeeby proposing revisions and attending Committee meetings. Correspondence should beaddressed to:Secretary, B5 Standards CommitteeThe American Society of Mechanical EngineersThree Park AvenueNew York, NY 10016-5990http:/go.asme.org/InquiryProposing Revisions. Revisions are made periodical
30、ly to the Standard to incorporate changesthat appear necessary or desirable, as demonstrated by the experience gained from the applicationof the Standard. Approved revisions will be published periodically.The Committee welcomes proposals for revisions to this Standard. Such proposals should beas spe
31、cific as possible, citing the paragraph number(s), the proposed wording, and a detaileddescription of the reasons for the proposal, including any pertinent documentation.Proposing a Case. Cases may be issued for the purpose of providing alternative rules whenjustified, to permit early implementation
32、 of an approved revision when the need is urgent, or toprovide rules not covered by existing provisions. Cases are effective immediately upon ASMEapproval and shall be posted on the ASME Committee Web page.Requests for Cases shall provide a Statement of Need and Background Information. The requestsh
33、ould identify the standard, the paragraph, figure, or table number(s), and be written as aQuestion and Reply in the same format as existing Cases. Request for Cases should also indicatethe applicable edition(s) of the standard to which the proposed Case applies.Attending Committee Meetings. The B5 S
34、tandards Committee regularly holds meetings, whichare open to the public. Persons wishing to attend any meeting should contact the Secretary ofthe B5 Standards Committee.viASME B5.50-20097/24 TAPER TOOL TO SPINDLE CONNECTION FOR AUTOMATICTOOL CHANGE1 GENERAL1.1 ScopeThis Standard pertains to the sta
35、ndardization of basictoolholder shank, retention knob, and socket assembliesfor numerically controlled machining centers with auto-matic tool changers. The requirements contained hereinare intended to provide toolholder interchangeabilitybetween machining centers with automatic tool chang-ers of var
36、ious types. This Standard is the inch solutionfor basic toolholder shank, retention knob, and socketassemblies. This design specifies an interchangeableretention knob with a 45-deg clamping surface.Section 2 of this Standard specifies the dimensionsand tolerances of toolholder shanks having 7/24 tap
37、ersintended for automatic tool change. These are intendedfor use with the corresponding basic retention knob andspindle sockets specified in sections 3 and 4 (see Table 1).Section 3 contains information for standardization ofretention knobs for use with the 7/24 connection systemdescribed herein (se
38、e Table 2).Section 4 specifies the dimensions and tolerances ofspindle sockets, drive keys, and key seats for machinetool spindles having 7/24 tapers intended for automatictool change (see Table 3 and Fig. 1). These are intendedfor use with the corresponding basic toolholder shankand retention knob
39、specified in sections 2 and 3.1.2 NoninterchangeabilityTool shanks conforming to ASME B5.18-1972 andASME B5.40-1977 are not interchangeable with toolshanks established in this Standard. Tool shanks con-forming to ISO 7388-1:1983 and retention knobISO 7388-2:1984 types “A” and “B” are not interchange
40、-able with this Standard. This also applies to additionalshank and knob designs that are in the draft stageswithin the ISO standards development system. Accord-ingly, the reader should note the warning statementincluded with the retention knob specifications shownin Table 2.Some incompatibility with
41、 existing automatic toolchange arms may arise from dimension M (Table 1).1.3 ClassificationThis Standard covers a basic toolholder shank withan “inch” threaded retention knob with 45-deg clampingsurface that is applicable to general-purpose machining1centers where loading and exchange of toolholders
42、 isaccomplished by automatic means. The termgeneral purpose is intended to differentiate betweenmachine designs for unusually high accuracy require-ments or designs intended to function with exception-ally high spindle rotational speeds coupled with higheraxis feed rates, such as is normally found i
43、n high-speedmachining. Tool shanks made to this Standard may beused with a variety of proprietary retention and/orflange locking systems.1.4 DefinitionsTerms relevant to this Standard and its applicationare as follows:automatic tool changer (ATC): mechanism for the transferof the toolholder between
44、a storage feature and the spin-dle or nonrotating socket.balance: when the mass centerline and rotational center-line of a rotor are coincident.basic cone: geometrically ideal conical surface that isgiven by its geometrical dimensions. These are a basiccone diameter, the basic cone length, and the b
45、asic rateof taper, or the basic cone angle.basic toolholder shank: unit that fits directly into the spin-dle or nonrotating socket of the machine and has provi-sion for automatic tool change.coolant hole: passage through the center of the retentionknob that allows through-the-spindle coolant to pass
46、.This hole also permits access to a tool set height adjust-ment screw if so equipped.drive key: device intended to assist in delivery of thedriving torque from the spindle nose to the tool.effective case: depth within a metal part, measured fromthe parts surface, where the minimum required hard-ness
47、 is present.retention knob: member of the toolholder retention sys-tem that provides a coupling point between the tool-holder taper and the spindle drawbar.spindle: component assembly of the machine tool, thefunction of which is to accept the basic toolholder shank.spindle nose: the part of a spindl
48、e into which the toolshank is accepted.ASME B5.50-2009Fig. 1 Optional Face-Mount Holes, 7/24 Taper Spindle SocketCCBBSection DD-A-AADD45 deg0.006 A0.008Taper sizes 30, 40, and 45Taper sizes 50 and 60 Atool angular orientation: mechanical feature to positionand retain the basic toolholder shank in a
49、specific angu-lar relationship to the spindle or nonrotating socket.tool shank: the part of a tool which mates with the taperin the spindle nose.1.5 References1.5.1 The following is a list of publications refer-enced in this Standard.ASME B5.18-1972, Spindle Noses and Tool Shanks forMilling MachinesASME B5.40-1977, Spindle Noses and Tool Shanks forHorizontal Boring MachinesASME Y14.5-2009, Dimensioning and TolerancingPublisher: The American Society of MechanicalEngineers (ASME), Three Park Avenue, New York,NY 10016-5990; Order Department: 22 Law Drive, Box2300, Fairfield, NJ 0700
