GB212521A - Improvements in automatic clutches - Google Patents

Abstract

212,521. Renault, L. March 10, 1923, [Convention date]. Clutches, friction. - In automatic friction clutches, particularly for preventing stalling of internal-combustion engines used in road or rail vehicles, and of the kind in which the engaging- force is dependent on the speed, and therefore the torque:, of the motor and is opposed by a force dependent on the load, the clutch is controlled by a differential device oppositely acted on by a centrifugally-derived force and the loadresponsive force, which is conveyed to the device by toothed gearing. A driving shaft 1, Fig. 1, carries a disc 3 in vhich are mounted the pivots 4, 4<1> of the expanding clutch shoes 5, 5<1> and the pivots 6, 6<1> of spring-controlled centrifugal masses 7. The shoes coact with a drum 11 rotatable on the driven shaft 2, and their free ends are connected by actuating-links 14, 14<1> to the casing 13 of a differential gear. The pinion 16 of the gear is Keved to a wheel 15 engaged by toothed sectors 8. 8<1> carried by the spindles 6, 6<1>, and the pinion 17 has in its boss a helical slot I7<1> engaged by a. pin 19<1> mounted in a spring-pressed' thrust rod 20 revoluble with the shaft 1. This rod contacts with a similar rod 18 revoluble with the shaft 2 and carrying a pin 19 coacting with a helical slot 11<1> in the boss of the drum 11, which is connected to a disc 10 on the shaft 2 by tension springs 12, 12<1>. Outward movement of the masses 7 turns the casing 13 in such direction as to expand the shoes 5, 5', while the load, by stretching the springs 12, 12<1>, causes relative rotation of the parts .10, 11, which is conveyed through the helical slots 11<1>, 17<1> &c. to the pinion 17, proportionately rotating it on the shaft 1 in a direction to release the clutch. The tensions of the springs are so arranged that the second action predominates when the resistance exceeds the motor torque at the particular speed. In the modification shown in Fig. 6, a plate clutch, comprising elements 21, 22 splined respectively to the hub of the driving-disc 3 and to the drum 11, has engaging-springs 29, 29<1> bearing on spur wheels 27, 27<1>, which act as presser members, and on washers 28, 28'. These washers are supported through shouldered rods 6, 6<1> by fixed bosses 23, 23<1>, against which bear also the bosses 24, 24<1> of the centrifugal arms 7. Slidable, non-revoluble sleeves 25, 25<1> have on their ends helicoidal teeth coacting with like teeth on the bosses 24, 24<1> and wheels 27, 27<1>, which mesh with a pinion 30 controlled in the same manner as the pinion 17. Relative displacement of the parts 10, 11 under load rotates the wheels 27, 27<1> so that they move to the right and relieve the spring pressure, while the centrifugal action of the arms 7 allows the sleeves 25 25' to move to the left and restore the spring pressure on the plates 21, 22.