1、AMERICAN STANDARD Microscope Objecti.ve Thre-ad . . ASA B1.11-1958 UDC 621.882.082:535.822:681.42 - - . - . REAFFIRMED 1994 FOR CURRENT COMMllTEE PERSONNEL PLEASE SEE ASME MANUAL AS-1 1 REAFF:IRMED 1989 FOR CURRENT COMMllTEE PERSONNEL PLEASE SEE ASME MANUAL AS-fl - .,. . . Society of Automotive Engi
2、neers The American Society of Mechanical Engineers THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS 29 West 39th Street, New York 18, N. Y. Intentionally left blank ERRATA ANSI B1.ll - 1958 (R1972) MICROSCOPE OBJECTIVE THREAD (JULY 1972) Page 5, Section 7 should read, American National Standard ANSI B1.
3、7-1965 (R1972) Page 6, Section 14 should read, Angle Deviation. Foreword The standardization of the microscope objective thread is one of the projects toward unification of screw thread standards among inch-using countries. In Great Britain, the Royal Microscopical Society had established standards
4、for microscope objectives in 1858, based on the Whitworth screw thread system, which were subsequently used throughout the world. The history of this standard is in the Transactions of the Society: 1858, p. 39; 1859, p. 92; 1896, pp. 389, 487; 1911, p. 175; 1915, p. 230; 1924, p. 266; and 1936, p. 3
5、77. In practice, American manufacturers of this thread have always employed modifications of the Whitworth form because of their preference for flat crests, such modified threads being completely interchangeable with the RMS threads. At the Conference on Unification of Engineering Stand- ards held i
6、n Ottawa, 1945, the American Delegation presented ASA Paper B1/57 and A.O. Drawing ED-95 giving limits of size for a truncated Whitworth thread. Since a thread form with rounded crest is preferred in Great Britain for optical instruments, it was recommended that the title of this document be amended
7、 to read, “Proposed Permitted Truncation and Tolerances for RMS Thread.” On the basis of this proposal a draft of a proposed American Standard, dated April, 1948, was cir- culated to the B1 Sectional Committee membership for comment. In conformity with comments received, a revised draft, dated Octob
8、er, 1954, was approved by Subcommittee No. 4 on Instrument Screw Threads and subsequently submitted to the Sectional Commlttee for approval. Final approval as an American Standard was given on January 7, 1958, by ASA. Any part of this standard may be quoted. Credit lines should read: “Ex2ractedjro r
9、eaffirmed 1953). Stub Acme Screw Threads (B1.8-1952). Buttress Screw Threads (B1.9-1953). Pipe Threads (B2.1-1945). . Square and Hexagon Bolts and Nuts and Lag Bolts (B18.2-1955). Socket Head Cap Screws and Socket Set Screws (B18.3-1954). Large Rivets-1/2 In. Diameter and Larger (B18.4-1950; Reaffir
10、med 1957). . Round Unslotted Head Bolts (B18.S-1952). . Slotted and Recessed Head Wood Screws (B18.6.1-1956). Hexagon and Slotted Head Cap Screws, Square Head Set Screws, Slotted Headless Set Screws Screw Thread Gages and Gaging (B1.2-1951). . Small Solid Rivets (B18.1-1955). (B18.6.2-1956) . Plow B
11、olts (B18.9-1950). Track Bolts and Nuts (B18.10-1952). Fire-Hose Coupling Screw Threads (B26-1925; reaffirmed 1953). . Hose Coupling Screw Threads (B33.1-1935; reaffirmed 1947). . Preferred Limits and Fits for Cylindrical Parts (B4.1-1955). . Quantity discounts as follows: In lots of IO, 20% oj list
12、 50, 25%; 100,30%,. PRICE $1 .oo 3.50 4.00 2.25 1 .so 1 .so 1 .so 2.50 1 SO 2.00 1.50 1 .so 1 .so 1.00 1 .so 1 .so 1 .so 1 .oo 1 .oo 1 .so A binder is available for holding these standards. It holds twenty-fve (25) pamphlets and gives every ad- vantage of a bound book together with the added conven
13、ience which comes from the ability to instantly insert, remove, or transpose sections of the contents. Price $3.25 Postpaid. A complete list of American Standards published by the American Society of MechanicaZ Engineers ob- tainable upon request. ASME members are entitled to a 20 per cent discount on a single copy of any standard.
