Variable proportion dispenser with cartridge replacement assembly

摘要

A variable proportion dispenser (2c) includes a housing (12c) which houses two pharmaceutical cartridges (6b). A reciprocating drive assembly includes drive stems (36c) extending from the pistons (46b) of each cartridge, a limit guide (76c) removably mounted to the housing, and a sliding body (66e, 300) mounted to the housing through the limit guide. Two one-way drivers (326) and threaded dosage adjusters (60c) are carried by the sliding body. Each one-way driver drives the drive stem into the cartridge through a drive surface to provide a range of dose selections. The user can thus control the amount and proportion of each pharmaceutical dispensed during each delivery stroke for each dispensing cycle. The housing is separable from the remainder of the dispenser, preferably using a cartridge release assembly (302), to allow spent cartridge to be replaced. Use of the cartridge release assembly also causes the one-way drivers to release the drive stems to permit the drive stems to be returned to their original positions.