摘要 |
A medical injector has a body with a displaceable plunger, which has a plurality of ratchet teeth along its length. An indexer is provided to engage the plunger, wherein the indexer is configured to allow the plunger to displace distally. The medical injector also includes an actuator having an engagement portion formed to engage the ratchet teeth. The.actuator is displaceable to a ready state, the engagement portion being displaced proximally relative to the plunger with the actuator being displaced to the ready state. The indexer prevents proximal movement of the plunger, thereby allowing the engagement portion to bypass one or more of the ratchet teeth with the actuator being displaced to the ready state. The plunger is slidably displaceable relative to the body, and rotatable relative to the body to selectively engage and disengage ratchet teeth engaged with the indexer and the actuator. |