US Patent 11696986 Multiple use disposable injection pen

A medication injection method where a dose set knob of a medication injection pen is rotated with respect to the housing of the medication injection pen during dose setting and dose correcting, a driver is selectively engages with the dose set knob, the driver being rotatably fixed with respect to the housing during dose setting and dose correcting, the driver is moved axially with the dose set knob during the dose setting and the dose correcting, and the driver is rotated with the dose set knob during an injection.