Manual-operation fixed-dose repeatedly-used braking mechanism

The utility model discloses a manually-operated fixed-dose repeatedly-used brake mechanism, and relates to the technical field of injection equipment. An inner body; the driving rod is movably arranged in the inner body and is used for performing axial reciprocating motion; the counting ring is used for displaying the quantitative injection times of the injection pen; the push rod is arranged in the driving rod and is used for pushing the rubber plug of the medicine bottle forwards in a fixed stroke so as to realize quantitative injection; the injection key is used for applying acting force to the driving rod; the key cover is arranged at the rear end of the injection key and used for covering the injection key; the refill frame is used for containing a medicine bottle, and the end of the refill frame is connected with the inner body; when the injection button is pushed forwards once, the driving rod and the push rod can be pushed to move forwards by a fixed stroke, and when the driving rod moves forwards, th