Patent GB-190709249-A (GB)
Title: Improvements in and relating to Mechanical Horns.
Inventor: HUTCHISON MILLER REESE
Filed: 1907-04-20
Granted: 1907-08-15
Abstract: 9249. Hutchison, M. R. April 20. Gongs &c.- Relates to improvements in such as are described in Specification No. 2456, A.D. 1907, in which the sound is produced by a diaphragm vibrated by a rotating cam engaging a stud upon the diaphragm. In the form shown in Fig. 4, the diaphragm 7 is clamped between the front 3 and the casing 1, cork washers 8 being arranged as shown. The stud 9, Figs. 4 and 6, of hard steel is secured to the diaphragm by a washer 11 and a rivet 10 of softer metal. The cam wheel 12 is fixed to-the hollow spindle 14, mounted in a bearing 15, and is rotated by the flexible shafting 17 driven from any rotating part as described later. A lubricator 21 is mounted in a boss 20 which is arranged diametrically opposite the boss 19 through which the flexible shafting passes, so that, if it is desired that the shafting shall be arranged on the other side of the casing, the lubricator 21, flexible shaft 17, ferrule 18<1>, spindle 14, and cam wheel are all removed, the casing turned through an angle of 180 degrees, and the parts replaced. In order to regulate the intensity of the sound, the bearing 15 may be pivotally supported, being pressed towards the diaphragm by an adjustable screw, against the action of a spring. The casing 1 is also provided with holes to allow the escape of any liquid which may find an entry into the casing. To facilitate the bending of the diaphragm at the point of attach. ment of the stud, the washers 11 are provided with rounded edges. The cam wheel should strike the stud in the direction of the grain of the diaphragm. The hard portion of the stud may rotate in the supporting rivet in order to reduce friction. Instead of using a stud such as 9, a projection 36, Fig. 8, may be formed in the diaphragm itself, arranged at a right-angle to the grain of the diaphragm. To regulate the pressure between the cam wheel and the stud, the hardened part of the latter may be conical and the cam wheel capable of axial adjustment, or the surface of the cam wheel may be inclined so that a slight axial movement of the wheel will produce a comparatively large variation in the pressure on the stud. The intensity of sound may be adjusted in the first place by means of the cork washers 8. The projections on the cam may be unequally spaced or the cam may be rotated eccentrically. Two or more diaphragms with separate horns or with a common horn may be arranged around a single cam wheel. The flexible shaft may be driven by hand-operated gearing, or by an electromotor controlled by a manually or electrically actuated clutch, or by a friction wheel engaging any revolving part of the engine as shown in Figs. 10 and 12. The forked end 52 of the flexible shaft embraces two pins 51 in the hollow spindle 38 carrying the grooved friction disk 37, adapted to be brought into engagement with the revolving part 60. The hollow spindle 38 is carried by a bracket 39 pivoted on the pin 40 secured to a bracket 40<1> fixed to the dash-board of the vehicle. The bracket 39 is provided with a sector 41 having a number of holes 42 therein, through one of which passes a bolt 43, clamping the operating arm 44 to the sector 41. The arm 44 can be adjusted over any of the holes 42, aud is actuated by a spring 47 and chain 48. The lever 44 is provided with brake blocks which can be brought into contact with the disk 37, so that the rotation of this disk, due to inertia, may be rapidly stopped when the disk is drawn away from the part 60.