Currently, we are designing an arc-shaped flat spring with an inner circumference of φ25 x H10 x t0.5 and one part cut out by 40 degrees (material: SUS430).
Since we want to set this arc to hold a round-shape object with an outer circumference of φ25, we are thinking of mounting it with a larger diameter, but it is acceptable how much the diameter can be mounted. I am worried about stress.
Is there any material that can be used as a reference for examination?
Mr. Masato, Thank you for your continued support.
Regarding the stress of arcuate flat springs, the following stress calculation formula may be helpful. The formula below is a formula for calculating the stress in the case of an arc-shaped retaining ring. (The maximum stress part is a point on the opposite diameter of the cut edge.)
Stress: σmax = 32Pr (cosα + 1) / πd ^ 3P = Load r = Radius α = Central angle of missing circle / 2π = Pi d = material’s thickness.
Nice to meet you. Excuse me for a sudden reply to the topic.
I am also having trouble with similar issues, and I would like to ask for your help. How was the coefficient 32 above calculated? The material thickness and radius of the arc are included in the above, but I would like to know how to apply the material length.
Spring Newbie, thank you for posting!
32 in the formula for σmax is the value of circular second moments of area ⇒ Z = πd ^ 3/32. By the way, the formula before the transformation of σmax is as follows. σmax = Pr (cosα + 1) / Z. Regarding the material length, the area moment of inertia of the thin plate is ⇒ Z = bh ^ 2/6, so the area moment of inertia does not include the plate length. For reference, in the case of a cantilevered thin flat spring, σ = 6Pl / bh ^ 2, and l is the material length.
