US181604A - Improvement in door-bells - Google Patents

Description

0. W. STOW.

l noon-HELM.

l No.181,604, Patented Aug. 29, v187B.

NITED i'rATES PATENT IMPROVEMENT IN Doon-BELLS.

Specication forming part of Letters Patent No. 181,604, dated August 29, 1876; application tiled June 2, 1876.

of which the following is a specification:

AThe invention relates to the peculiar construction of the parts with reference to securing them to the door, and compensating for the various thicknesses of doors, all as hereinafter described.

In the accompanying drawing, Figure l is a lfront elevation of the striking mechanism of a door-bell which embodies my invention 5 and Fig. 2 is a vertical section on a line passing through its center of a door-bell which embodies my invention.

A designates a central and rotating cani, held in place, as hereinafter described, within a central chamber. The stud B, which supports the bell C, is secured to and projects from the base-plate D. An oscillating hammer, E, is hun'g to said plate D, said hammer carrying an arm, a, which engages with the central cam A, so as to be tripped thereby, and it is held in contact with said cam by means of the spring b, constantly pressing upon the arm a ofthe hammer E. By rotating the cam in such direction that its top travels away from the arm c, said arm will be thrown outward as it rides up the incline of the cam, and its opposite end inward, as indicated by broken lines in Fig. l. So soon as the radial shoulder ofthe cam passes the hammer-arm a, the spring b forces the arm a suddenly inward, and the hammer proper outward, to strike the bell C in a well-known manner. I secure the central vcam A tirmly to its shaft F; and to the opposite end, by means of a nut or other convenient fastening, I secure a crank, G, or other handle, by means of which the shaft may be rotated. Upon each side ofthe door H I secure a. circular plate, c c', the latter being secured to the outside by means of screws, and may be as ornamental as desired, and also its contour may be of other form than circular. Upon each of these plates I form hollow bosses d d, and the cam-shaft F is fitted to turn in these bosses, as showin The exterior of these bosses should be of a size to tools.

In order to secure the device upon a door, a hole corresponding in size to the. bosses is bored straight through the door. The crank orhandle is removed from the cam-shaft, and the plates c c are placed upon the door, with their bosses resting in the hole so made in the door to receive them, and the outer plate c' may be secured by screws when the crank can vbe replaced on the cam-shaft. In the back side of the base-plate D I form a circular recess, of a size anddepth to correspond with the size and thickness of the circular plate c, and which recess in the drawing is filled by said plate. In front of the plate c and its recess a chamber is formed in the plate D, of a diameter large enough to allow the central cam free play, and of a depth fully equal to the thickness ofthe cam, for a purpose herei after specified. At one side of this chamber the walls are cut away, as shown, in order to allow the hammer-arm a and cam A to come in con tact with each other. In order to secure the boss-plate D upon the door, its proper position is rst determined by placing it over the plate c, and letting said plate into its recess in the plate D, when said plate may be secured in place by screws. The central cam is then prevented from working toward the bell by the front wall of the cam-chamber, which chamber should be shallow enough to hold the cam within the door anddeep enough not to bind the cam and cause it to turn hard. The cam, by striking the plate c, will be prevented from Working in the opposite direction-that is, the end chase of the cam and its shaft is regulated by the plate c and front wall of the cam chamber. The cam shaft should be made long enough for the thickest door, and by the above construction Will readily accommodate itself to varying thicknesses of doors, the only variance heilig that in a thin door the crank end will project a little farther' than it does in a thick door. The device is also very cheaply made, and can be much more conveniently attached than can ordinary crank-bells.

I claim as my inventionl. The plate D, having the central can1- FFIE.

chamber in the back to receive the cam a, subi 3. The plate D, carrying the stud. B, and stantially as described, and for the purpose having the Walls of the central chamber upon speced. one side cut*J away, substantially as described,

2. The cam A, having the bearings for its and for the purpose specified. shaft secured to the door, and detached from v ORSON W. STOW. the plate which carries the hammer, substan- Witnesses: tially as described, and for the purpose speci- RALPH I. CRISSEY,

fled. H. J. HOLT.

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