Knob assembly, operation part and electronic endoscope

The invention discloses a knob assembly which is used for an operation part of an electronic endoscope, the operation part comprises an upper shell serving as a shell, the knob assembly comprises a first knob, a second knob, a second gear and a first gear which are sequentially arranged and coaxial from outside to inside of the shell, the first knob can drive the first gear to rotate, and the second gear can drive the second gear to rotate. The second knob can drive the second gear to rotate, and the second gear and the first gear are located in the shell. The invention further discloses an operation part and an electronic endoscope, and the cost can be reduced. 本发明公开了一种旋钮组件，用于电子内窥镜的操作部，操作部包括作为壳体的上壳，旋钮组件按由壳体外向内的顺序，包括依次设置且同轴的第一旋钮、第二旋钮、第二齿轮、第一齿轮，其中，第一旋钮可驱动第一齿轮旋转，第二旋钮可驱动第二齿轮旋转，第二齿轮和第一齿轮位于壳体内。还公开一种操作部及电子内窥镜，可以降低成本。