GB231741A - A new or improved brake testing device for automobiles - Google Patents

Abstract

231,741. Cowdrey, C. F. Aug. 26, 1924. Dynamometers, rotary-transmission. - Comprises a device. for testing the action of a brake upon the wheel of an automobile, and consists of means for rotating a wheel of the automobile continuously under brake resistance, and means for indicating the force required to rotate the wheel under these conditions. The device is mounted in a truck and may be moved up to engage a wheel jacked up off the ground for the purpose. A head 21 is adapted to be secured to the wheel and consists of a central part fitted with a gimbal joint 41, 45 and having radiating rods 25 carrying clamps 26 and adjustable simultaneously in an inclined manner to and from the central part by bevel gear 32, 34, so that the head may be clamped to wheels of different sizes. On the truck are mounted two columns 13, 14 pivoted on shafts 16, between which columns is guided a gear casing 18. This casing may be raised and lowered by a screw 92 and bevels 95. Below the casing is an electric motor 46 which drives the main shaft 20 of the device through a gearing into which is introduced a yieldable member the movement of which measures the power transmitted. A pinion 48 on the motor shaft drives a shaft 50 through a gear wheel 49. This shaft in turn drives through gears 54, 55 a shaft 56 which is journaled at one, end in a bracket 51 supporting one end of the shaft 50, and at the other end in the side 58 of the casing. On a non-rotatable sleeve in the shaft 56 is journaled an arm 60, which together with an arm 62 journaled on a sleeve 63 supports a stub-shaft 61 carrying two planet wheels 66, 67 formed in one. These gear with wheels 65, 75, of which the former is secured to the shaft 56 while the latter is on the sleeve 76 which carries a gear 64 meshing with a wheel 77 on the main shaft 20. In one with the arm 62 is a sector 69 which gears with a wheel 70 in mash with a rack 72 normally pushed up by a spring 73. The upward movement of the rack is limited by a set screw 97. In use, the truck is brought up to the automobile wheel, which has been raised and has had offered to it the head 21, and the squared end of the shaft is inserted in the inner gimbal ring. The brake is applied to the wheel and the motor started. The arms 62, 60 move about their axes and force the rack drum against the spring, a graduated drum 81 turned through the gear 80 from the rack indicating the force required. The motor is always driven in. the same direction, each end of the shaft 20 being squared and used to drive opposite wheels. The columns being pivoted the shaft 20 can be swung through an angle to align with an axle which is not horizontal, for instance, a steering stub shaft.