Patent GB-190318128-A (GB)
Title: Improvements in Continuously Variable Speed Gear and in Clutches and Link Motions connected therewith.
Inventor: DANN AUGUSTUS CARDIGAN FREDERI
Filed: 1903-08-21
Granted: 1903-10-15
Abstract: 18,128. Dann, A. C. F. Aug. 21. Variable - speed gearing.-A crank a on the driving-shaft b is coupled by a rod c to a slotted link d fixed to trunnions monnted in bearings in a standard e. A screw f, mounted in the slot, engages a block g coupled by a rod h to a pin h<1>, which is secured in a pair of holes formed in discs h<2> keyed to a shaft i. A bevel-wheel i<1> on the shaft i engages with bevel-wheels loosely mounted on the driven shaft o. A number of holes are formed in each disc h<2>, so that the relative position of the wheel i<1> may be altered by changing the position of the pin h<1>. The wheels are each formed integral with, or fixed to, one member of a clutch, the other member gearing with the wheel i being secured to the shaft o. These clutches are preferably of the roller type, each of the rollers being provided with a band of teeth to engage teeth in the clutch shells, thereby ensuring a rolling motion for the rollers when moving between the engaged and free positions. These clutches are so arranged that an oscillating movement of the shaft i is converted into continuous motion, in one direction, of the shaft o. An intermittent motion of the shaft o is obtained if only one clutch is employed. By adjusting the position of the block g so as to alter the length of the arm or crank d, the speed of the shaft o is varied. Upon the screw f is fixed a worm-wheel f<1> in gear with a worm f on a shaft f Two pairs of curved arms m, n are pivoted to extensions of the standard e, the centre of curvature of the arms being the pivot of the link d. Each pair of arms is adapted to engage the free members of clutches m<1>, n', the other clutch members being fixed to the shaft f<3>. The arms are held out of contact with the clutches by means of a spring p, and are brought into engagement therewith by means of a lever p<1>, conveniently operated by a pedal. When a pair of arms engage the clutches, the screw f is rotated to move the block g due to the oscillations of the link d, the direction of the movement of the block depending upon the pair of arms in engagement. The shaft o may carry a bevel-wheel o<1> in gear with wheels q<1>, q<2> loosely mounted on the shaft. Either of the wheels q<1>, q<2> can be fixed to the shaft by means of a clutch r, according to the direction in which the shaft is required to run. Preferably, the operating-lever s for the clutch r is arranged so that the clutch can be disengaged at any speed, but can only be engaged at slow speed. A slot s<1> in the lever s has a central enlargement adapted to engage the head t<1> of a spring-pressed pin t passing through the slot and through a hole in the standard e. A plate attached to the block g is adapted to engage the inner end of the pin t, and pushes it out of engagement with the lever s at the required speed thereby enabling the lever to be operated to throw the clutch r into action. A number of sets of gearing may be arranged in connection with the driving-shaft.