Patent GB-490539-A (GB)
Title: Improvements relating to the jacking up of road vehicles
IPC: B60S9/04
Filed: 1937-02-18
Abstract: 490,539. Jacking-apparatus on vehicles. REID, H. C. Feb. 18, 1937, No. 4870. [Class 79 (iii)] Vehicle jacking means comprises two or more legs or struts of different length pivoted to an axle or other vehicle part and adapted, when brought into engagement with the ground, to come into operation successively to raise the vehicle in steps as it is moved backwards or forwards, the struts being relatively movable so that they can be closed together to economize space both in the raised and lowered positions. When one of the rear wheels of the vehicle is being raised it may be automatically braked so that the vehicle may still be moved by power transmitted through the differential to the other rear wheel. In the form shown in Figs. 1 and 3, channel section struts 3, 4 pivoted to a bracket 1 on an axle 2 are normally retained by springs 6 in a raised position, the strut 3 seating in the strut 4. A cord 7 attached to an arm 3a on the strut 3 enables the device to be drawn down from the driver's seat, a strap 9 causing the strut 4 to follow the strut 3, the strut 4 being retarded by a pair of tie rods 10, 11 with a spring joint 12, the rod 11 being pivoted at its end 11a to the vehicle frame. The tie rods relieve the strut 4 of bending strains when over its dead centre and supporting the vehicle. The strut 3 only reaches the ground when the wheel tyre is deflated. The tie rods may be connected to the strut 3 or may be replaced by spring- means between the struts tending to separate them but overpowered by the springs 6 when operative. A roller 13, Fig. 7, may be mounted in slots 4a in the end of the strut 4 and normally pressed downwards by a spring 4b, so that, if it should become rusted up, the weight of the vehicle, when the strut is in use, breaks away the rust. When applied to a front axle, the cord 7 may be attached to an extension of the strut 3 beyond its pivot 5 instead of to the arm 3a. The struts may be arranged so that when folded up out of action, they project beyond the ends of the vehicle, carrying transverse members acting alternatively as bumpers, and as ground engaging members. In a further modification, three jacking legs or struts are provided, the middle one being of H-section so as to be adapted to house the other two, such a form being useful when applied to raise the whole side of the vehicle. Several arrangements are described for automatically applying the brake to the rear driving wheel when this is raised. As shown in Fig. 8, the cord 7 instead of being attached directly to the strut 3, is connected to a grooved block 19 around which is passed a cable 18 leading from the strut 3 to a pivoted arm 15 located behind a brake operating arm 16, so that the brake arm is operated conjointly with the strut. The arm 15 may be pivoted on the shaft 17 to lie alongside and engage the arm 16 or the arm 16 may be extended and the cable 18 connected directly to the end thereof. To operate a hydraulic brake, as shown in Fig. 11, the cable 18 is connected to an arm 22 integral with a cam 20 adapted to press the brake shoe 21 into engagement. The cam 20 may be coupled to a second cam 20a operating the opposite shoe. In cases where the brakes are normally operated by a pull on a transverse brake rod, as in the Girling system, the cable 18 may be connected to one arm of a bell crank lever, the other arm of which terminates in a fork straddling the rod and engaging a collar thereon, Fig. 12 (not shown). In all the above arrangements only the brake of the wheel to be raised is operated and normal actuation of the brakes is unimpeded.