Patent GB-483938-A (GB)
Title: Improvements relating to double clutches especially for power vehicles
IPC: F16D21/06
Filed: 1937-02-15
Abstract: 483,938. Variable-speed gearing; friction clutches; locking levers. HERING, E. Feb. 15, 1937, Nos. 4569, 4570, and 4571. Convention dates, Feb. 15, 1936, June 2, 1936, and Jan. 30, 1937. [Classes 80 (ii) and 80 (iii)] The engine shaft 1, Figs. 1 and 6, of a motor vehicle is adapted to be connected alternatively to a shaft 8, connected to a driven shaft 8a through change-speed gearing controlled by a lever 71, or to a hollow shaft 12, connected to the shaft 8a through a free-wheel clutch and toothed gears which give a low-speed drive, through a double friction clutch comprising discs 5 and 10 mounted on the shafts 8 and 12 respectively, the disc 5 being disposed between the face of a flywheel 2 secured to the shaft 1 and a pressure plate 6 located on one side of a plate 4 secured to the flywheel, while the disc 10 is disposed between the other side of the plate 4 and a pressure plate 14. The two pressure plates are controlled by a single set of radial levers IS actuated by a pedal-operated control sleeve 24. As shown in Fig. 1, each lever is in pivotal connection with a bolt 17, carried by a projection 15 extending from the plate 6 through an aperture in the plate 4, and carries-a roller 19 co-operating with a plate 20 secured to the plate 14. With the pedal released, the parts occupy the position shown, the clutch 5 being engaged by springs 9 while the clutch 10 is free. When the pedal is depressed'to an intermediate position, the rollers 19 act on the plate 14: first to engage the clutch 10 and then disengage the clutch 5. On depressing the pedal further the rollers 19 move off the part 20 to a part 21 of the plate 4, whereby the clutch 10 is also freed. As shown in Fig. 6, each lever 18 carries a roller 41 coacting with a part 42 of the plate 14 and carries also an adjustable pin 38 coacting with a member 39 secured to the plate 4. Instead of carrying a roller 41, the lever may be pivoted on a pin carried by the member 14. The pedal 27, Fig. 4, is retracted by a spring- loaded arm 30 engaging a pin 28 secured to the pedal. The arm 30 has a recess 29 whereby, by the further resistance offered to the descent of the pedal, the operator is made aware that the pedal has reached its intermediate position. Means may, however, be provided for maintaining the pedal in the intermediate position. Thus, as shown in Fig. 9, the pedal 27, normally retracted by a spring 59, carries a pin 28a coacting with a spring-loaded arm 30a. The latter is pivoted at 32a and carries a spring- loaded arm 47 provided with laterally-projecting cams 49 and 50. On depression of the pedal to its intermediate position, the pin 28a engages a notch 29a in the arm 30a, running along the surface 51 of the cam 49 and over the peak 52 into a recess 53 in that cam. The pedal is now locked against return movement, but may be depressed further, the pin then riding out of the notch 29a and running along the inner surface 56 of the cam 50, returning along the outer surface 54 of the cam 50, and may be unlocked by slightly depressing the pedal. Alternatively, as shown in Fig. 11, a pin 28b carried by the spring-retracted pedal cooperates with a spring-loaded arm 30b pivoted at 32b and carrying laterally-extending cams 49b, 50b. An arm 60, pivoted on the pin 28b, is normally maintained in the position shown by a spring 64 and carries a pin 66b. On depressing the pedal to its intermediate position, the pin 28b engages a notch 29b in the arm 30b and the pin 66b runs on the surface 51b of the cam 49b and then, if descent of the pedal is stopped, falls into a notch 53b in the cam 49b, as shown in Fig. 16. This locks the pedal against return movement. To unlock, the pedal is slightly depressed so that the pin 66b can move, under the action of the spring 64, below the cam, in which position the pedal can either be retracted or depressed further. If the pedal is not stopped in the intermediate position, the pin 66b can pass direct from the surface 51b to the surface 54b of the cam 50b. The Specification as open to inspection under Sect. 91 states that the rollers 19 may be replaced by balls. This subject-matter does not appear in the Specification as accepted.