Patent ID: 8759704

Claim:
A switch comprising: a click spring that generates a tactile action by being pressing down and comprises a circumferential edge and a movable contact; a spring holding sheet attached on the click spring; a switch base which is provided with a first stationary contact and a second stationary contact, and which supports the spring holding sheet; and a nub disposed on the spring holding sheet and having a non-linear acting load to displacement characteristic; wherein the circumferential edge of the click spring is continuously in contact with the first stationary contact; wherein the movable contact of the click spring is configured to contact the second stationary contact at a time of the tactile action; and wherein a spring constant k 11 , a spring constant k 3 , a spring constant k 12 , a displacement S 1 , and a displacement s 11 satisfy following inequalities: k11<k3, k12>k3, and 0<s11<S1, where: the spring constant k 11 is a gradient of a tangent line at an origin point of an acting load to displacement characteristic curve of the nub, the displacement S 1 is a displacement corresponding to a peak acting load in an acting load to displacement characteristic curve of the click spring and the spring holding sheet, the spring constant k 3 is a gradient of a line connecting a point corresponding to the peak acting load and an origin point of the characteristic curve of the click spring and the spring holding sheet, the spring constant k 12 is a gradient of a tangent line at an arbitrary point within a non-linear portion of the characteristic curve of the nub, and the displacement s 11 is a displacement corresponding to an intersection point of the line having the gradient k 11 and the line having the gradient k 12 .