1、Driving elements Pulleys for fiat transmission belts Dimensions, nominal torsional moments Antriebselemente: Flachriemenscheiben: Masse, Nenndrehmomente Supersedes September 1972 edition As it is current practice in standards published by the International Organization for Standardization (ISO), the
2、 comma has been used throughout as a decimal marker. For connection with International Standards IS0 22 - 1975, IS0 99 - 1975 and IS0 100 - 1975 published by the International Organization for Standardization (ISO), see Explanations. Dimensions in mm 1 Field of application This standard specifies th
3、e principal dimensions, the nominal torsional moments and the material to be used for pulleys for flat transmission belts. 2 Dimensions, designation The pulleys for flat transmission belts need not conform to the illustration; only the dimensions specified must be adhered to. General tolerances: DIN
4、 7168 - m For hub length 1: + IT 14 according to DIN 7151, lower deviation O Tolerance zones for hub bore: - H7 for one-piece pulleys for flat transmission belts (spoke pulleys and solid pulleys) - U7 for two-piece pulleys for flat transmission belts (spoke pulleys) Any other tolerance zones subject
5、 to agreement Solid pulleys o/( O Cu c - O a) 0 UY Page6 DIN 111 oooooc NONbNT a NCVNNNC - O 5: NO cvN Lo N O O O d 7 8 N I IIIIII UJm N/ .- CJ Lo (v - oooc ONOC (vcvmc O (v - O N O O W - Lo c l- O O (u UJ l- l- - O O Co 1 - DIN 111 Page7 3 Material GG-20 in accordance with DIN 1691. Other materials
6、 subject to agreement. 4 Finish In the case of one-piece (IT) pulleys for flat transmission belts, the hub shall be flush with the rim on one side (hub refer- ence edge), .e., one face each of the rim and of the hub shall lie in the same plane. The other hub face shall either be set back or projecti
7、ng relative to or flush with the other rim face. In the case of two-piece (2T) pulleys for flat transmission belts, the hubs shall always be arranged symmetrically with regard to the rim, on both sides they shall either be “flush“ or “set back“ or “projecting“ (see figure). Keyway: PN feather keyway
8、 conforming to DIN 6885 Part 1, deep pattern (in the case of 2T pulleys for flat transmission belts the feather keyway is offset from the parting line by 90“) PN with grub screw (set screw) subject to agreement. KN taper keyway conforming to DIN 6886 (in the case of 2T pulleys for flat transmission
9、belts the taper keyway shall be on the parting line) Position of the deepest point of the hub keyway subject to agreement. Heights of crown: The heights of crown indicated apply to drives with horizontal shafts. In the case of drives with vertical shafts and for special belts the heights of crown mu
10、st be agreed. Balancing: General : In a single plane, quality grade Q 16 in accordance with VDI 2060 at u = 30 m/s for d, 400 mm or at n = 1500 l/min ford, I 400 mm Balancing shall be carried out without keyway on a smooth balancing arbor. Subject to agreement: Balancing in accordance with VDI 2060
11、with keyway, butwithout parallel key,and/or in two planes Recommendation: In two planes, quality grade Q 6.3 for operating speed if a) u 30 m/s or b) the diameter to rim width ratio equals d, : b2 20 m/s Recommendation for rim types 2 or G: The choice of rim type Z or G is governed by the type of dr
12、ive. In general, the following must be observed: In the case of a gear ratio of more than 3 it is recommended to choose the rim type Z for the smaller pulley. Page8 DIN 111 Standards referred to and other documents DIN 748 Part 1 Cylindrical shaft ends; dimensions, nominal torsional moments DIN 1691
13、 Cast iron with lamellar graphite (grey cast iron) DIN 6885 Part 1 Drive type fastenings without taper action; parallel keys, keyways; deep pattern DIN 6886 Stressed-type fastenings with taper action; taper keys, keyways; dimensions and application DIN 7151 IS0 standard tolerances for sizes from 1 t
14、o 500 mm nominal dimension DIN 7168 Part 1 General tolerances; linear and angular dimensions VDI 2060 Rules for assessing the balancing condition of rotating rigid bodies Previous editions DIN 11 1 : 04.23, 12.54, 09.72 Amendments As compared with the September 1972 edition the following amendments
15、have been made: a) the heights of crown have been diminished from d, = 315 mm b) the second example of designation has been deleted, as the hub lengths are now clearly correlated to the other pulley c) the contents and the layout have been revised with regard to the rules for drafting standards dime
16、nsions Explanations The diameters dl, widths b and heights of crown h, in- to make selection and storage easier for the user. Speci- cluding the permissible deviations, are in accordance fications regarding the balancing of pulleys for flat with the specifications of the following IS0 Standards: tra
17、nsmission belts and the torsional moments TN in N m IS0 22 have also been included. Widths of flat transmission belts and corresponding The hub lengths of the IT Pulleys for flat transmission Dullevs belts have been chosen in such a manner as to provide .I IS0 99 Diameters of pulleys for flat transm
18、ission belts IS0 100 Crowns of pulleys for flat transmission belts When revising the previous standard special importance was attached not only to bringing the specification into line with the IS0 Standards but also to specifying the hub dimensions (maximum bore, hub diameters, hub lengths and their
19、 correlation with rim widths) in order the possibility of placing the solids and spokes on the mid-line of the rim, which explains a certain irregularity in the values. Owing to practical experience gained with high-capacity flat belts the heights of crown adopted in this standard have been reduced, especially as regards the upper dimensional range, and they conform to International Standard IS0 100 only up to a diameter of 280mm. Thus a longer service life of the pulley and a good guid- ance of the belt is assured.
