Patent GB-523937-A (GB)
Title: Improvements in or relating to apparatus for testing motor and other vehicles
IPC: G01L5/28
Filed: 1939-01-18
Abstract: 523,937. Dynamometers; systems for testing motor vehicles. TECALEMIT, Ltd. Jan 18, 1939, No. 1785. Convention date, Jan 18, 1938. [Class 106 (ii)] [Also in Group XL] Comprises apparatus in which the vehicle is allowed to run down an incline with its brake applied and the time taken compared with a standard time. The vehicle to be tested is run up an incline 3 to the station 2 at the upper end of the section AB of the test incline. Here the wheels engage a beam 12 carried by levers 13 pivoting about an axis 14. The lower arms 13d of these levers are locked by levers 16 pivoting on axis 18 at right angle to the axis 14. These levers 16 have the arms 16a pivotally connected together by a rod 19 to which is attached a cable 20 passing over guide pulleys to a pulley 24 connected to a gear 26 driven from a pinion 27 operated by a handle 28. The beam 12 when the handle 28 is turned in the correct direction to release the levers 16 falls under its own weight and the vehicle is released. The beam is returned when the arms 16 are raised by a cable 29 suitably guided and attached to any one of the levers 13, a spring section in the length of the cable allowing the beam to be raised to full position before the levers 16. When the vehicle starts to run down the test length AB of the track the front wheels depress a spring lever and cause switch 40 to energize a relay making the circuit of a time switch controlling a signal lamp on a standard 65<SP>1</SP>. The time switch causes the lamp to light up for the time which a vehicle with efficient brakes takes to cover the distance AB. If the vehicle takes a greater time than standard to cover the path AB, the lamp is extinguished before the point B is passed and the brakes are in order. If the switch 41 at point B is operated to put out the lamp the brakes are defective. In an alternative circuit two lamps of different colours are used. A record of the test may be made by introducing a ticket 81 under a character carried by a spring strip 78 above which is a spring stamp 77 which is raised by a tooth 73 engaging a lug 74. The tooth is carried on a disc 72 which is revolved by a time switch in the standard time referred to above. If the brakes are good the character 79 which is a " G " is stamped. If the time taken between points A,B is less than standard the switch 41 energizes a solenoid 83 to move the strip 78 forward and bring mark 80 carrying a " B " into position. A latch 84 released by a solenoid 85 energized by the time switch restores the parts. In a modification the cam disc is clutched at the proper instant magnetically to a continuously rotating disc and is returned by a spring upon release of the clutch. Signalling and recording means may be combined and circuits are given to illustrate this combination. For testing the grip and resistance to skidding, the path from B to C is made of the same character as the road and again the time taken by a standard tyre taken as a basis of measurement. The contact 41 initiates the test and similar apparatus is used as in the case of the brake test, a switch 42 completing the test, and a signal device 65<SP>2</SP>, used. Similar recording devices. may be used. Contact members are arranged along each side of the test path which when engaged by the tyres of the wheels cause an indication of skidding to be given the contacts being connected to the brake testing signal circuit. When the vehicle is at rest against the abutment 12, the steering gear may be examined for " play ." A similar printing device with hand operated switches may be used to record this test, the test tracks are covered by a tunnel to protect them from the weather and, being dark. may be used for testing head lamps. For this purpose a photo-electric cell 140 is arranged at such a point that it is not affected by the light beam emitted by head lamps if these are at the correct adjustment. The point B may be the starting point of this test and a lamp is arranged to light up when the vehicle passes this point and remains alight for a certain time. Another lamp of a different colour lights up if the cell is influenced by the beam. A similar printing apparatus as previously described may be used to record the result. Mechanical means may be used to operate signal and recording means for the brake, skid and tyre tests, and may actuate with the aid of clockwork movable disc signals.