| 摘要 |
A pen-type drug injection device in which the absolute position of a movable control member (10), such as a dose setting member (32) is determined by at least one transducer responsive to movement of said control member to convert mechanical energy into electrical energy to output an electrical signal, a drive circuit (26) for receiving said electrical signal and for outputting an output drive signal, and a display device (58/62) for receiving said output drive signal and displaying a variable image representing a parameter that varies consequent on said movement. The transducer includes piezoelectric elements (16) which operate switches and the display is a bistable display (14), e.g. an electronic paper display so that the display function is self-powered without a requirement for a battery or the like. The parameter displayed may be for example a dose volume, a count of doses delivered, progress and/or completion of a dose, etc. The drive circuit is an absolute position encoder and detects the actual position of the control member and does not deduce the position by counting pulses. |
