1、mK: 62-272.2 DEUTSCHE NORMEN January 1971 I DIN Helical Compression Springs made of Flat Bar Steel Calculation I 2090 Zylindrische Schraubendnickfedern aus Flachstahl; Berechnung The present Standard applies only to mecial Durnose desians, in respect of which the springs are subject to special requi
2、rements as regards the space they occupy. Helical compression springs of flat bar steel can be used to advantage in such cases, viz: a) w o u n d o n e d g e (the longer side of the cross-section being perpendicular to the axis of the spring); this enables long lifts, short compressed lengths and a
3、high ratio of the external to the internal coil diameter to be achieved (the longer side of the cross-section being parallel to the axis of the spring); this enables a long overall length and a low ratio of the external to the internai coil diameter to be achieved. Helical compression springs made o
4、f square steel bar with a square cross-section shall be avoidel Helical compreseion springs of round steel bar should be used instead, as the latter can be stressed to the same values for a lower weight of material used and for a shorter overall length. b) f 1 a t w o u n d Spring wire of square or
5、rectangular cross-aection, dram by patented processes for cold coiled helical compression springs, can only be obtained by special arrangement with the spring wire manufacturer. The bar material of trapezoidal cross-section which was formerly used for the manufacture of hot formed helical compressio
6、n springs is no longer available in Germany. Bar material of square Or rectangular cross-section for the manufacture of hot formed helical compression springs is only available if ordered in large quantities. The cross-section of this bar material assumes a trap- ezoidal shape when coiled. Y Dm Shea
7、r stress: TI -= P b in mm in kp/mm c - 3 Spring rate f,f2 Spring travels in mm, related to spring fBl - L, - Side of cross-section perpendicular to asis OS the spring P compression forces Pl,P2 Spring travel in mm, related to spring compression force PBl Side of cross-section parallel to axis o2 the
8、 spring in mm Number of active spring turns Total number of spring turne h if ig Dm w - b Coil ratio (u 24) Da External coil diameter in mm Di Internal coil diameter in mm Dm Mean coil diameter in mm 6 - Dm3 if b2 h2 G Spring travel: f - .P Number of turns: b2 h2 - G 3 6. c Dm if - i g =if+2 See pag
9、e 2 for coefficients yand E G Lo =I 42 $1 Pl 32 Bi E. 7 %i w Modulus of shear in kp/mmi Length of unloaded spring in m Lengths of loaded spring in mn Length of compressed spring in mm (all coil turns in abutment with one another) Spring compression forces in kp, related to spring lengths LI, L2 Spri
10、ng compression force in kp related to length of compressed spring Elasticity (resilience) coefficient, dependent on ratio of cross-section side lengths b/h or h/b respectively Shear stress under load P Shear stress under load PBl Stresa coefficient, dependent on ratio of cross-section side lengths b
11、/h or h/b respectively in kp/mm2 in kp/mm2 Continued on page 2 8einvrrkouf der Normbltter durch Beuth-Vertrieb GmbH, Berlin 30 und Kln DIN 2090 engl. Preisgr. Page 2 DIN 2090 - 1 1,l 1,2 1,3 1J 1.5 1,6 1J 1,s 1,9 2 22 2,4 2,6 2.8 3 32 h Or b E 539 5,61 5.67 577 538 6,02 417 63 63 6,68 6,87 726 7,67 8,W 8,51 8,95 939 W 34 3,6 3.8 4 4.5 5 9,83 103 1073 11,19 1533 13,48 References to other standards DN 2089 Sheet 1 (Freliminary Standard) Helical springe made of round wire and rod; calcula- tion and design of compreseion springe
