A push-type lock for fire-blocking door which includes a base body, a frame mounted on the base body, a latching member pivotally mounted on the frame, an actuating piece mounted also on the frame, and a safety release unit penetratingly secured for the frame. The safety release unit includes a rod member, an inner end and an outer end formed on both ends of the rod member respectively, a spiral spring coupled axially to the rod member and positioned between the inner end and an inner surface of the frame, and a hot-melt member sleeving the rod member between the outer end and an outer surface of the frame and subject to being melted away when heated. As a consequence of the hot-melt member being melted away, the rod member will be moved to the inside of the frame due to the compressed spiral spring, thus allowing the rod member to be moved to a position blocking up the way the latching member can be withdrawn to the inside of the frame. In this case, the latching member is prevented from being withdrawn to the inside of the frame, thus securely latching the door when a fire breaks out.
展开▼
