Tubular door lock with a bell

Claim 1

A tubular door lock with a bell comprising, an inside knob constructed with a locking structure and a pipe shaft cut with two straight slots, a bell bored with a hole which is penetrated by said pipe shaft and which has two notches in which respective projections of a fixing frame fit, said fixing frame containing four radiating arms, two of said arms having axial projections connected to a fixing plate, the other two of said arms each being bored with a hole, and the fixing frame further having two projections located in the notches of said bell, said fixing plate containing a hole for a screw to penetrate to link said bell to an outside knob, and two pins, the pins being inserted in the respective holes in said fixing frame, two sticker springs, each pivotally carried on a respective one of the pins for striking internally against the bell, each striker spring having a central pivot, a contact head adjacent the pivot, a pair of spring arms extending outwardly from the pivot, and a striker at the end of each arm, a rotating unit having a protruded circle at each of its two sides for matching with said fixing frame and said fixing plate, and four protrusions able to squeeze and overpass the contact heads of the striker springs, an assembling plate having two lunar slots for assembling with said inside knob, a square opening for assembling with a square shaft of said outside knob, four hooks for further spring respectively to hook around and an ear for connecting with one end of said further spring, said further spring having one end connected with said ear and the other end fixed at said fixing plate, so that said fixing plate can automatically return to its original position after either of the knobs is turned around, said square shaft being connected with a linking plate to rotate the linking plate, a latch to be pulled or released by the linking plate and which has a shaft hole to be penetrated by said square shaft of said outside knob to rotate and to move a latch bolt, and characteristics that the rotation of said outside knob will be transmitted to move said rotating unit causing said protrusions sequentially to press against the contact heads of the respective striker springs, with pressure of a respective protrusion against a respective contact head effecting pivotal movement of a respective striker spring on its respective pivot until one of the strikers engages the interior of the bell where upon subsequent release of the contact head on passage of the protrusion causes the striker to strike against the interior of the bell due to the resilience of the respective spring arm.