To provide a contents discharging mechanism intended to reduce the burden of a movable passage member to an operating force and an impact applied to a trigger lever and avoid breakage of a layer of the operating member, the movable passage member driven by the operating member, the malfunction-preventing stopper and/or the cover body when, e.g. an operating member undergoes an impact with a malfunction-preventing stopper attached.

The contact areas of the trigger lever and the movable passage member in the interlocking action parts are increased. Instead of a rotary malfunction-preventing stopper, a freely removable stopper having a C-shaped cross-section is used to increase the contact area with the contact part for prevention of malfunction on the side of the movable passage member. The malfunction-preventing stopper has a longitudinally bending impact-absorbing shape. Using a malfunction-preventing stopper having an impact-absorbing shape, two or more members movable on operation, e.g. the trigger lever, an operation button and/or the movable passage member, are received simultaneously. The configurations may be combined.