| 摘要 |
A power-operated typewriter in which a key action mechanism cooperates with a power-operated mechanism to transmit type key depression into power-actuated movement of a respective typebar. The key action mechanism comprises an integrally formed, flexible, parallelogram-shaped structure of which a portion of the key lever forms one side and a portion of the actuating lever forms another side. A support lever, fixed to the typewriter frame, and a fourth lever form the other two sides. All the levers are connected by relatively more flexible joints and the lengths of the levers are chosen so that key depression translates into upward movement of the actuating lever. A cam lever has an arm in contact with an extension of the actuating lever and upward movement of the actuating lever causes the cam lever to rotate about a first pivot to bring its gripping surface into contact with the power roll. A bellcrank lever connected to the cam lever at the first pivot point is caused to rotate about a second pivot and actuate the typebar. During power actuation the distance between the point on the power roll contacted by the cam lever's gripping surface increases. After completion of the upward cycle of the actuating lever it is deflected from contact with the cam lever to prevent repeat action.
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