Patent ID: 8746226

Claim:
A backward momentum generating device for a toy gun arranged to extend through an opening in an internal wall located between a housing of the toy gun and a stop wall of the toy gun, wherein when a piston unit produces compressed air in the housing, the backward momentum generating device is pushed in a moving direction of reciprocal motion of the piston unit to induce a reaction force on the stop wall so as to produce an effect of shooting recoil force, characterized in that the backward momentum generating comprises: a front-section tube, which extends through the opening of the internal wall into the housing and is movable with the reciprocal motion of the piston unit and comprises a front-section spring and a front-section inner rod received in the front-section tube, the front-section spring being fixed to an internal front surface of the front-section tube, the front-section inner rod being arranged at a non-fixed end of the front-section spring and extending outside an internal back end of the front-section tube; a weight, which is coupled to the front-section tube between the internal wall and the stop wall and forms therein a hollow channel, the front-section inner rod extending through the internal back end of the front-section tube into the hollow channel; and a back-section tube, which extends from the front-section inner rod to be received in the channel formed through the weight and comprises a back-section spring within the hollow channel and a back-section inner rod received within the hollow channel, the back-section spring being fixed to an internal front surface of the back-section tube, the back-section inner rod being arranged at a non-fixed end of the back-section spring and extending beyond a back end of the back-section tube and the hollow channel of the weight to engage the stop wall.