Claims
- 1. A tubular door lock comprising an inside knob having a locking structure and a pipe shaft formed with a pair of elongate slots defining respective arcuate portions of the pipe shaft, an outside knob with a hollow square shaft in which is located a flat plate having one end adapted to engage the locking structure of the inside knob for rotating the flat plate, at least two holes in the square shaft in each of which is located a ball for radial up and down movement therein, an assembling plate having two arcuate slots for receiving the respective arcuate portions of the pipe shaft and with a square hole centrally of the arcuate slots for receiving the square shaft so that both knobs are connected for rotation through the assembling plate, a latch connected with a linking plate, the linking plate having a shaft hole with a pair of circumferential recesses, the shaft hole receiving the square shaft therein with said balls in line with the recesses, the flat plate extending through the square shaft for rotation by the locking structure between an unlocked position in which opposite edges of the flat plate engage the balls and urge the balls outwardly into said recesses to drivingly connect the square shaft and the linking plate, and a locked position in which the flat plate is rotated to release the balls from said recesses thereby disconnecting the square shaft from the flat plate.
- 2. A lock as defined in claim 1 which includes a pair of coil springs surrounding the square shaft and retaining the balls in position.
BACKGROUND OF THE INVENTION
This is a divisional of application Ser. No. 923,739 filed Oct. 28, 1986, U.S. Pat. No. 4,800,833.
A door for preventing burglary is usually equipped with a lock and in addition with a door bell so that persons indoors may be warned that somebody is at the door. The inventor had once filed an application, "A BELL LOCK" with Ser. No. 683,360 for a patent in United States, but given it up later. The inventor filed, again in United States, an application of the same title with a different structure which was numbered with Ser. No. 685,491 and granted a patent numbered U.S. Pat. No. 4,577,584. But the structure of said U.S. Pat. No. 4,577,584, whose bell will not work if it is locked from the inside, can not totally function as a bell.
The purpose of this invention is to provide a tubular door lock whose outside knob can be turned around whether it is locked or not, and this lock can function as a bell completely, too.
The invention provides a tubular door lock whose inside knob and outside knob are not combined to interact directly but indirectly. An assembling plate is set with a square shaft hole for matching with a square shaft of the outside knob and lunar slots for matching with a pipe shaft of said inside knob. Said pipe shaft is set with a rotating unit and a bell. The rotation of either of the knobs can start the rotating unit, and the protrusions of said rotating unit are then to push and overpass gradually a projection set at a knocking spring and make one of its ends raised up at first. When the pushing force disappears, said spring will automatically return back by its own elasticity knocking on the bell for ringing. When the locking structure of said inside knob is locked up, the flat plate in the square shaft of said outside knob can be turned around to make the steel balls of said square shaft move inwards so that the rotation of said square shaft do not activate the linking plate of the latch, enabling said inside or outside knob to rotate idly only.
US Referenced Citations (11)
Divisions (1)
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Number |
Date |
Country |
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923739 |
Oct 1986 |
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Patent Grant
4852922
