1、0 British Standards Institution. No part of this publication may be photocopied or otherwise reproduced without the prior permission in writina of BSI COPYRIGHT British Standards Institute on ERC Specs and StandardsLicensed by Information Handling ServicesBSI BS*bllJy 85 81 lb24bIa9 0072694 3 I BS 1
2、434 : 1985 Foreword This British Standard, which has been prepared under the direction of the Non-ferrous Metals Standards Committee, supersedes BS 1434 : 1970 which is withdrawn. This standard is a full technical revision of the 1970 edition and takes into account the corresponding requirements of
3、IEC 356 : 1971 Dimensions for commutators and slip-rings published by the International Electrotechnical Commission (IEC). The principal objectives in preparing the revised edition were as follows: (a) to extend the size and shape ranges covered in accordance with demand for copper section for uses
4、ranging from mass produced commutators through to special purpose applications (where present limits appear to have satisfied demand, no changes have been made); (b) to provide adequate choice within practical limits so that cost/accuracy and size demands can be optimized; (c) to take, in each area
5、of the specification, the best elements from both BS 1434 : 1970 and IEC 356 : 1971 and combine them to give an improved and more practical standard; (d) to simplify presentation and eliminate redundant text while retaining the practical essentials. Useful information has been included in appendix A
6、 which lists the preferred nominal heights (see A.l) for commutator sections supplied as bar or coil, and the preferred nominal diameters (see A.2) for finished commutators, in which material complying with this standard is supplied. Compliance with a British Standard does not of itself confer immun
7、ity from legal obligations. COPYRIGHT British Standards Institute on ERC Specs and StandardsLicensed by Information Handling ServicesBS 1434 : 1985 Contents Foreword Committees responsible Page Inside front cover Back cover Specification Scope 2 Definitions 2 Information to be supplied by the purcha
8、ser General 2 Material 2 Tolerances on dimensions and shape Sampling 9 Determination of hardness 9 2 2 Appendix A Preferred nominal sizes Tables 1 2 3 4 5 6 7 8 9 10 11 12 13 Chemical compositions and minimum hardness Permitted proportions of bars of different actual lengths in any one delivery of m
9、ill lengths Tolerances on length for specified lengths Tolerances on length for blanks and segments Tolerances on height Thickness measurement positions for commu- tator bar segments or blanks Tolerances on thickness Tolerances on specified angle Tolerances on shape error and shape constants for the
10、 shape of the side faces Maximum deviation from straightness of bar Maximum twist for bars, blanks and segments Preferred heights, H, in mm, of sections for commutator bars Preferred nominal diameters, in rnm, of finished commutators Figures 10 2 3 3 3 4 4 7 7 7 8 8 10 10 Segments 3 positions for th
11、ickness, angle and shape Qeviation from specified angle 7 Tolerance on shape of the convex thick edge Tolerance band for the shape of the thin edge (referee method) 9 Main dimensions of cross sections of commu- tator bar segments or blanks and measuring 5 9 9 Measuring area for Vickers hardness 1 CO
12、PYRIGHT British Standards Institute on ERC Specs and StandardsLicensed by Information Handling ServicesBSI BSrLY34 85 m Lb2Ybb9 O072696 7 m BS 1434 : 1985 Specif ication 1 Scope This British Standard specifies requirements for flat sided wedge-shaped copper sections in bars (straight lengths and coi
13、ls), blanks and segments, suitable for the manufacture of commutators for rotating machines, in the following size ranges: (a) thick edge thickness (T) up to 15 mm; (b) height (H) from 6 mm to 200 mm; (cl height to thin edge ratio (Hlr) up to 50. This standard does not cover copper for flat face com
14、mutators, commonly rectangular section strip and bar, which is covered by BS 1432 and BS 1433. NOTE. The titles of the publications referred to in this standard are listed on the inside back cover. (f) the thickness dimensions ri and r3, or t and T (see 6.4, table 6 and figure 2) and the tolerance c
15、lass (see 6.4 and table 7); (9) the angle, (Y (see 6.5, table 8 and figure 3); (h) the shape (flat or convex) of the thick edge (see 6.9 and figure 4). 3.3 Commutator segments The following information shall be provided: (a) the information detailed in items (a) to (h) of 3.2; (b) the length of the
16、commutator segment, Lu (see 6.1.3, table 4 and figure 1); (c) the height of the commutator segment, Hu, and the tolerance class (see 6.3, table 5 and figure 1); (d) a drawing of the shaped segment required, especially if the blank is other than L-shaped. 2 Definitions 4 General For the purposes of t
17、his British Standard the following definitions apply. 2.1 commutator section. A solid, flat sided product of wedge-shaped cross section, with or without a stepped section (see figure 21. 2,2 commutator bar. Commutator section, intended for use in the manufacture of commutator blanks or segments, usu
18、ally supplied in mill, multiple or specified lengths. NOTE. Commutator bar in the smaller section sizes may be supplied in coils. 2,3 commutator blank. A short length, cut or fabricated from a commutator bar, that is of plain shape, 2.4 commutator segment. A short length, cut or fabricated from a co
19、mmutator bar, that is shaped. 3 Information to be supplied by the purchaser 3.1 General The information given in 3.2 and 3.3 shall be supplied by the purchaser in the enquiry and order to assist the manufacturer in supplying the correct material. 3.2 Commutator bars and blanks The following informat
20、ion shall be provided: (a) the quantity required; (b) the material grade (see table 1); (c) the length and whether this is to be supplied in mill lengths (see 6.1.1 and table 21, specified or multiple lengths (see 6,1.2 and table 31, blanks and segments (see 6.1.3, table 4 and 3.3); (d) for the smal
21、ler sections, supplied in coil, the coil size and/or mass; (e) the height (H) and tolerance class (see 6.3, table 5 and figure 2); Copper commutator bars (straight lengths and coils), blanks and segment shall comply with the material requirements specified in clause 5 and the tolerances on dimension
22、s and shape specified in clause 6. Methods for sampling and the determination of hardness shall be as specified in clauses 7 and 8 respectively. 5 Material The chemical composition and the hardness, determined either by the Vickers or the Brinell methods in accordance with clause 8, shall be as give
23、n in table 1. Table 1. Chemical compositions and minimum hardness Material grade (see item (b) of 3.2) 1 2 Chemical composition CU-ETP-2 (C101/2) of Cu-Ag-3 of or CU-FRHC BS 6017 BS 601 7 Minimum hardness 85 I 80 6 Tolerances on dimensions and shape 6.1 Length 6.1.1 Milllengrhs, The proportions of b
24、ars of different actual lengths that are permitted in any one delivery shall be as given in table 2 (see item (c) of 3.2). 2 COPYRIGHT British Standards Institute on ERC Specs and StandardsLicensed by Information Handling ServicesBSI BS*l1434 85 W Lb24bb 0072b7 9 Actual bar length 6 mm mm - 100 100
25、200 200 500 Permifted proportions Tolerance mm f0.3 f0.5 f 1.0 6.1.2 Specified or multiple lengths. The tolerances on specified length shall be as given in table 3 (see item (cl of 3.2). Table 3. Tolerances on length for specified lengths (see item (c) of 3.2) (Cl X denotes corners for measurement o
26、f twist. Figure 1. Segments (see items (b) and (c) of 3.3) 3 COPYRIGHT British Standards Institute on ERC Specs and StandardsLicensed by Information Handling ServicesBS 1434 : 1985 6.2 End squareness for blanks and segments The ends of blanks and segments shall be cut square to the edges within 0,00
27、6 mm per 1 mm of the height dimensions H or Hu shown in figure 2. 6.3 Height The tolerances on the height dimensions Hand Hu shown in figures 1 and 2 shall be as given in table 5 (see item (e) of 3.2 and item (c) of 3.3). Table 5. Tolerances on height (see item (e) of 3.2 and item (c) of 3.3) Height
28、, H or Hu Tolerance Normal Close I35 h mm Hu)* 3 3 3 3 3 3 3 3 3 3 3 3 6 6 6 6 6 6 6 6 6 6 6 6 h, mm (1/2 Hu)* 5 6 6 7 8 9 10 11 12 14 16 18 20 22 25 28 31 36 40 45 50 56 63 (li2 Hu)* mm Hu)* 7 9 9 11 13 15 17 19 21 25 29 33 34 38 44 50 58 66 74 84 94 106 1 20 (Hu - 6)“ h, IH - h, for all sizes) Val
29、ues rounded to the nearest whole millimetre. NOTE 1. For heights that are intermediate between successive values in the above table, thickness measurement positions corresponcing to the next lower value of Hu .are used. NOTE 2. If the lower reference plane is used for the rneasure- ment of stepped s
30、ections, the thickness measurement positions for t, t2 and t, are ho (nominal) + h, and ho (nominal) + h, respectively. 4 COPYRIGHT British Standards Institute on ERC Specs and StandardsLicensed by Information Handling ServicesBS 1434 : 1985 1 T (a) Commutator bar and blanks T (b) Commutator blanks
31、to be shaped, or segments 4 A 7.E X Reference plane L-J Alternative reference plane (c) Stepped commutator bar Figure 2. Main dimensions of cross sections of commutator bar, segments or blanks and measuring positions for thickness, angle and shape (see also items (e) and (f) of 3.2 and table 6) 5 CO
32、PYRIGHT British Standards Institute on ERC Specs and StandardsLicensed by Information Handling ServicesHeight, H Angle, pl mm 6 20 40 80 140 Q mm degree 20 3.6 1.8 40 3.6 1.8 - 80 3.6 1.8 I- 140 I 3.6 I- Table 8. Tolerances on specified angle (see item (9) of 3.2) Height, H or Hu mm 6 20 40 80 140 6
33、 mm 20 40 80 140 200 Angle, 01 degree degree 3.6 - 3.6 - 3.6 - 1.8 3.6 - 1.8 3.6 - 1.8 3.6 - 1.8 3.6 - 1.8 3.6 - 1.8 1.8 3.6 - 1.8 Negative tolerance on specified angle, A t, - A t, Normal I Close I Ex: mm mm mm 0.032 0.020 - 0.025 0.016 - 0.050 0.032 0.020 0.040 0.025 0.020 0.032 0.020 0.020 0.050
34、0.032 0.025 0.040 0.025 0.020 0.032 0.020 0.020 0.063 0.040 0.025 0.050 0.032 0.020 0.040 0.025 0.020 - 1 0.050 I 0.040 - 0.040 0.032 6 COPYRIGHT British Standards Institute on ERC Specs and StandardsLicensed by Information Handling ServicesBSI BS*3434 85 Lb24bb9 0072703 7 M 41 Angle error II I Top
35、limit on. thickness Lower Mit on thickness r Figure 3. Deviation from specified angle (see item (9) of 3.2) BS 1434 : 1985 6.6 Shape of side faces The shape of the side faces, Le. the convexity or concavity and flatness over height, shall be determined from the thickness measurements ti , t2 and t3
36、(see figure 2 and table 6) by calculating a shape error, A f, given by: where A ti, A tz and A t3 are the differences between the nominal and observed thicknesses, undersize values being negative and oversize values being positive. The shape error, A f, shall not exceed the tolerances given in table
37、 9. In addition, any gap at position hz (see figure 2 and table 6) between a straight edge spanning the positions hl to h3 and the actual side face shall not exceed the value, in mm, given by: Af 2 x- - where x, the shape constant, is given in table 9. Table 9. Tolerance on shape error and shape con
38、stants for the shape of the side faces Height, Angle, CY H or Hu mm mm degree 6 20 3.6 - 20 I 40 I 3.6 1 - I Tolerance on shape error, A f degree mm - f 0.025 3.6 -r 0.020 - f 0.032 3.6 f 0.020 - 50.032 3.6 +- 0.020 - f 0.040 3.6 f 0.025 - Lt: 0.050 3.6 f 0.040 Shape constant, x mm 0.025 0.040 0.050
39、 0.063 0.080 7 COPYRIGHT British Standards Institute on ERC Specs and StandardsLicensed by Information Handling ServicesBSI BS*h434 85 hb24bb 0072702 9 H BS 1434 : 1985 6.7 Straightness of bar The maximum deviation from straightness, measured between two points separated by the distances given in ta
40、ble 10 along a central longitudinal line on the edges and faces, shall not exceed the values given in table 10. 6.8 Twist The maximum twist, .e. the maximum deviation of one corner of either side face from a plane passing through the three other corners of that side face, shall not exceed the values
41、 given in table 11 for bars and segments. Table 10. Maximum deviation from straightness of bar Bar length, 1 I mm mm - 1 O0 100 500 500 - Maximum deviation from straightness. Measurement distances 2000 mm mm - 0.8 6.9 Shape of convex thick edge The shape of the convex thick edge shall comply with th
42、e following (see item (h) of 3.2): (a) the highest point shall be within f 0.2T of the line of symmetry, as shown in figure 4; (b) the radius of curvature of the highest point, r, shall not exceed 2 mm or 0.5T, whichever is the smaller; (cl the total contour of the thick edge, including the highest
43、point shall be within the 1 mm tolerance band shown in figure 4. 6.10 Shape of the thin edge The total contour of the thin edge shall be within the tolerance band of 1 mm or 0.5t, whichever is the smaller, shown in figure 5. 1 Table 11, Maximum twist for bars, blanks and segments Product Blanks and
44、segments Length of bar, 1, or length plus height of segment or blank, L+H mm 1 500 (L tH) 100 Maximum twist For any 100 mm part of the length mm 0.5 0.5 0.05 0.05 % of (L + Hl For any 500 mrn part of the length mm - 2.5 0.05 I * For segments, see figure I. 8 COPYRIGHT British Standards Institute on
45、ERC Specs and StandardsLicensed by Information Handling Servicesk T lmm -7 Figure 4. Tolerance on shape of the convex thick edge (see item (h) of 3.2) l E I lmm or O. 5f /IA I t lowest point I Figure 5. Tolerance band for the shape of the thin edge f 7 Sampling 7.1 General The materials shall be sam
46、pled as specified in 7.2 and 7.3. NOTE. The sampling of mill, specified or multiple lengths is not specified but it is recommended that, unless otherwise agreed, one sample should be taken per 100 lengths or fraction thereof. Specified or multiple lengths shortened by sampling are accepted ac good d
47、elivery. 7.2 Material supplied in coils One sample shall be taken per 10 coils or fraction thereof. 7.3 Blanks o segments One sample shall be taken per 1000 blanks, or segments, or fraction thereof. 8 Determination of hardness The hardness shall be determined by means of either the Brinell hardness
48、test in accordance with BS 240, or the Vickers hardness test in accordance with BS 427. Routine measurements shall be made on the side face of the bar, segment or blank. In cases of dispute, the Vickers hardness test shall be the referee method. The hardness shall be determined in the cross-hatched
49、area as shown in figure 6 and shall be calculated as the average of two hardness measurements made on each of the different samples, .e. a total of four hardness measurements. I Figure 6. Measuring area for Vickers hardness (referee method) COPYRIGHT British Standards Institute on ERC Specs and StandardsLicensed by Information Handling Services, BSI BS*L434 B5 M 1b24bb 0072704 2 M BS 1434 : 1985 Appendix A. Preferred nominal sizes A.1 The heights of sections for commutator bars should be selected either from the preferred heights given in table 12 or, for intermediate
