Patent GB-1466132-A (GB)
Title: Device for testing tyres for vehicles
IPC: G01M17/02
Filed: 1974-06-05
Abstract: 1466132 Testing vehicle tyres REGIE NATIONALE DES USINES RENAULT and AUTOMOBILES PEUGEOT 5 June 1974 [6 June 1973] 24960/74 Heading B7C Apparatus for testing a vehicle tyre 2 comprises a drivable continuous track 1, a hub 16 capable of freely rotatably supporting a wheel carrying the tyre 2, a carriage 9 carrying the hub 16, a frame 4 on which the carriage 9 is slidably mounted, means for sliding the carriage 9 to urge the tyre 2 against the track 1 at a given load, and means for pivoting the hub 16 to vary both the steering angle α and the camber angle # of the wheel and tyre assembly. The track 1 may be formed by the periphery of a rotatable drum and the apparatus may, as shown in Fig. 1, be arranged such that the tyre 2 contacts the track 1 on a generally vertical part thereof. As illustrated in Fig. 2 the hub 16 may comprise a ring 23 carrying ball bearings 24 to enable free rotation of the wheel, the ring 23 being journalled on pins 22, 22a carried by a further ring 21. The ring 21 is in turn journalled on pins 20, 20a carried by a sleeve 19 slidably mounted on a shaft 11 mounted on the carriage 9. Rods 17a, 17b, 17c and 17d connect the ring 23 to a yoke 29 journalled on pins 28 carried by another yoke 27 which is itself journalled on a pin 26 fixed to a further sleeve 25 slidably mounted on the shaft 11. The yoke 29 is also connected by a rod 30 to a structure 38 fixed to the frame 4. Sliding movement of the sleeve 25 along the shaft 11 thus causes the yoke 29 to pivot about the pins 28 and hence the ring 23 to pivot about the pins 22, 22a and vary the camber angle #. Rotation of the yoke 27 about the pin 26 causes the ring 21 and hence the ring 23 to pivot about the pins 20, 20a thus varying the steering angle α. In the Fig. 2 embodiment the sleeve 25 is moved by means of a reciprocable piston 44 and cylinder 46 device whose pistonstroke length is controlled by adjustable stops 51, 52. The yoke 27 is rotated by means of piston 65 and cylinder 66 device whose pistonstroke length is controlled by adjustable stops 71, 72. In an alternative embodiment (Figs. 6- 8, not shown) the sleeve 25 and member 27 are connected to a motor driven gear assembly capable of moving the sleeve and/or member as appropriate either to impart a constant angle α and/or # to the hub, or to continuously vary the angle α and/or # in sinusoidal fashion with a selected amplitude and with or without a phase difference between the angles α and # when both are continuously varied. The carriage 9 may be moved by means of a jack 14 fixed to a base 3 of the apparatus. In an alternative embodiment, Fig. 3, the carriage 9 is connected to a device 94 mounted on a platform 95 slidable along rails 96 resiliently supported on a frame 97 fixed to the base 3. The platform 95 may be moved by means of a screw 102 and nut 103 arrangement in order to move the carriage 9 and hence bring the tyre 2 into contact with the track 1. The device 94, which incorporates a motor and a system of gears, may then be used to reciprocate the carriage 9 such that the tyre 2 is applied against the track 1 under a load which varies in sinusoidal manner with a selected amplitude. Jacks 106 and 112 may be provided for immobilizing the platform 95.