THIS paper attempts to clarify the functioning of the volute spring and to eliminate the confusion which is at present connected with volute-spring computations. A number of contradictory formulas are currently in use, many of them usable only for one coil or for half a coil at a time.
The paper shows the relationship between the volute spring and other forms of coiled springs; it explains the similarities and dissimilarities of formulas for these spring forms, with particular emphasis on stress determination.
Because of the high stress invariably encountered in some part of a volute spring, it is clear that special consideration must be given to proper bulldozing and load-checking methods, and a set of specifications incorporating these methods is suggested.
In order to steer clear of excessive overstressing and the attendant spring settling, the stress reductions obtainable with partial tapering of the spring blade are discussed in detail.
As a proof for performance results which may be expected from a volute spring design, the life testing of the springs is considered indispensable, and an account is given of results in the past and of prospects in the future.