DEVICE FOR CHANGING OPERATING FORCE OF LENS DEVICE

摘要

An outer tube body of a device for changing operating force is connected to a gear part of a zoom ring of a lens barrel to rotate the outer tube body together with the zoom ring. The outer tube body has a cylindrical shape and includes a hollow part into which an inner tube body whose rotation is restricted is arranged. Grease is interposed in a gap is formed between an inner peripheral surface of the outer tube body and an outer peripheral surface of the inner tube body. A load caused by viscosity resistance of the grease is applied against rotation of the outer tube body together with the zoom ring. The inner tube body can be displaced in a direction of the center axis so that area of a sliding contact region between the outer tube body and the inner tube body is changed.

主权项

1. A device for changing operating force of a lens device, comprising:
an operating ring rotatably provided around an outer periphery of a lens barrel; a rotating body connected to the operating ring to rotate around a rotary shaft in a predetermined direction together with rotation of the operating ring, the rotating body having a cylindrical peripheral surface centering on the rotary shaft; a non-rotating body whose rotation is restricted, the non-rotating body having a cylindrical peripheral surface being arranged by having a gap at a position facing the peripheral surface of the rotating body in a noncontact manner; viscous fluid having viscosity interposed in the gap, the viscous fluid applying a load caused by viscosity resistance thereof against rotation of the rotating body rotating together with the operating ring to produce operating force required to rotate the operating ring by the load; an operation member for changing operating force to be operated by an operator to change the operating force; and a non-rotating body driving device for changing a value of a load against rotation of the rotating body by moving the non-rotating body in a direction of the rotary shaft corresponding to an operation of the operation member for changing operating force by an operator to change a size of an area of a sliding contact region in which the peripheral surface of the rotating body and the peripheral surface of the non-rotating body face each other.