Apparatus for opening and closing cover

Abstract

An activating device for a cover has: a shaft unit having a rotary shaft; an arm unit which is coupled to the cover and the rotary shaft; and an actuator which drives the rotary shaft. The actuator has: a motor having a first output portion; a first reducer having an input portion and an output portion; and a second reducer having an input portion and an output portion. The reciprocal of a reduction ratio of the second reducer is larger than a quotient which is obtained by dividing a product by a torque that is required for rotating the output portion when a torque is not applied to the input portion, the product being obtained by multiplying a difference between a maximum torque that is applied to the output portion when the cover is opened, and a torque that is required for rotating the output portion when a torque is not applied to the input portion, with a ratio of a torque that is a remainder of a torque applied to the output portion after subjecting to a mechanical loss due to the second reducer, to the torque applied to the output portion.

Dependencies are inferred from the claim text.