Patent GB-190320770-A (GB)
Title: An Improved Registering Differential Speed Indicator
Inventor: RICHARD JULES
Filed: 1903-09-26
Granted: 1903-12-10
Abstract: 20,770. Richard, J. July 4, [date applied for under Patents Act, A.D. 1901]. Speed indicators; registeringrelative motion. -An instrument for recording angular motions of a rotating shaft, relatively to a wheel l rotating uniformly at the same mean speed, is shown plan. The shaft tested is connected directly or through toothed gearing o<1>, o<2> to a shaft o, which drives a wheel n. This wheel and the wheel are loose on a shaft m<1>, and are attached to bevel pinions in gear with an intermediate bevel pinion m, which is carried on an arm of the shaft m<1>. When the speed of the rotating wheel l has been adjusted to equality with the mean speed of the wheel n, irregular turning of the latter causes rotary movements of the shaft m<1>. The shaft m<1> carries a serrated disc p, against which the padded arms t of an aligning shaft r may be pressed by a finger key. The shaft r carries an arm s and a pen to mark on a revolving vertical drum b. A brake spring s<1> can be applied to the disc p to check vibration. The Specification gives the error caused by back-lash in the gearing as about one degree of angular motion of the shaft being tested. The recording drum b may be driven by the shaft being tested, or at uniform speed by a spring motor. In the latter case, to enable the irregularities recorded to be referred to definite positions of the shaft being tested, this shaft carries a cam or an electric contact to mark each revolution of the shaft on the recording drum b, mechanically by means of a lever, or electromagnetically. The wheel l is rotated through a variable speed gear by any available motor, a spring drum c being used in the construction shown, for portability. The drum c drives a wheel e, and a pinion e<2> on a vertical shaft, and may be stopped by applying a brake spring to the wheel e. The pinion e<2> drives a second wheel e', which is pressed inwards by a spring e<3>, so that a disc g situated between the faces of the wheels e, e<1> is driven frictionally. The shaft of the disc g carries a long pinion g<1>, which engages a crown-wheel h<1>, geared to the wheel l. The shaft of the disc g is supported by a sliding bar, which is movable by a rack and worm gearing and a milled head i, to adjust the disc g and the speed of the wheel l. The adjusting gear is connected with a graduated disc k, to show the speed opposite a stationary pointer. The disc k or the sliding bar may be connected with a pen to mark the speed on the recording drum b. The speed of the motor c is controlled by a centrifugal governor, shown separately in Fig. 5. A plate u<2>, on the vertical shaft of the pinion e<2>, Fig. 4, carries two pivoted brake-blocks u, which are held by springs v attached to levers x<1>, adjustable by screws on the plate u<2>, so that the blocks u revolve in contact with the inside of a cylindrical box w, made dust-proof. In order that the motor c may be set to a definite rate, it drives a pointer d round a graduated dial, for comparison with a standard chronometer. In a modification, for showing considerable variations in angular velocity, the shaft r carries a small aluminium recording cylinder, and a style is moved along this in a straight line so as to mark on it.