| 摘要 |
This disclosure provides a device for delivering coded data in the form of knocks, comprising an electric motor capable of bi-directional rotation, a control utility to command the motor to alternately rotate in two opposite directions; a knocking element coupled to the motor such so as to be rotated thereby; and an anvil element positioned so as to being successively impacted by the knocking element in each of the two rotational directions. |
