From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Article from 'The Autocar' magazine reviewing various permanently fitted and detachable car jacking systems.
| Identifier | ExFiles\Box 139\2\ scan0062 | |
| Date | 9th March 1934 | |
| 384 The Autocar March 9th, 1934. Views of the inexpensive Oto system. A jack with permanently attached handle shaft, is carried separately. in stock, and for small-sized cars the price is five guineas, for medium-sized cars seven guineas, and for large cars ten guineas. Extra is charged for fitting, but this is not a long job in most cases, especially if taken to the service depot at Donald Sessions and Co., Ltd., 906, Harrow Road, Willesden, London, N.W.10. Quite one of the most advanced jacks on the market is the Smith's Jackall, and in this case four jacks are permanently attached to the car and are operated hydraulically by means of a hand pump. Lubricant is forced through pipes to the four jacks. In order to raise the car a handle which is normally carried on the side of the scuttle is inserted into a neat control box situated in front of the passenger's seat, and a distributor pump is brought into action by pumping the lever backwards and forwards. A pointer on top of the control box can be moved to any of four positions ("front," "all," "rear," or "release") so that the two front jacks or the two rear jacks, or alternatively all four jacks, can be operated at the same time. The jacks are clamped to the axles. Modifications Dictated by Experience One usually finds that considerable modifications have been effected to such jacks since their original introduction, and, in fact, when the Jackall was first marketed in 1928, by S. Smith and Sons (Motor Accessories), Ltd., Cricklewood, London, N.W.2, the control box had more valves, so that each jack could be raised individually, instead of the front pair or back pair together, as is the present arrangement. Also, the D.W.S. jack in its original form was a very massive and heavy affair, but it has now been considerably lightened. A further improvement to the D.W.S. is the fitting of safety clips to overcome the danger of the jack accidentally falling open under vibration. The Smith's Jackall avoids this danger by means of a spring which the oil pressure has to extend when the jacks are being lowered, but which pulls back the jack when the oil pressure is released. The cost of the Jackall for cars up to 30 cwt. is twelve guineas, and for cars over 30 cwt. fourteen guineas. S. Smith and Sons (M.A.), Ltd., state that the front or rear wheels can be raised in twelve seconds, or the whole car in under half a minute. The entire hydraulic jacking system, which weighs about 45 lb., can be transferred on to another car when a change of cars is made. The position of the jacks with the D.W.S. (two for the rear axle and one in the centre of the front axle) and with the Jackall (one for each wheel) enables all wheels to be lifted at once, but there are also certain permanent jacks which lift the car from the centre of each chassis member; whilst by this arrangement only the two wheels on one side of the car can be lifted at a time, it does offer definite advantages in the way of simplicity of construction, and therefore appreciably lowers cost, and, of course, achieves the same object of facilitating greasing and cleaning. A jack of this latter type, which was first put on the market in October, 1933, and which has already become quite popular, is the Oto, made by Oto, Ltd., 37, Pavilion Road, Knightsbridge, London, S.W.1. On either side of the car a special bracket is clipped to the bottom flange of the chassis member and bolted beneath the running board. This arrangement provides for the lift being directly beneath the side member, but no drilling of the chassis is necessary. Normally, the bracket need not affect the ground clearance to any great extent, but when the car is to be lifted a hinged part of it is let down to take a special jack which is carried in the car in the ordinary way. This special jack, which has its handle permanently attached to it, is slipped up into the hinged bracket, and a sleeve on the handle engages with a catch on the running board to hold it in position. The handle has a detachable cross piece, and this is turned in a clockwise direction in order to lower the jack and raise the car. The illustrations make the operation quite clear. There are notches cut in the cross piece, so that it will give a narrow turning circle for winding fast, when the jack is not actually touching the ground, and a wider turning circle when the side of the car is being lifted. The complete Oto set—that is, the two brackets, the jack, and the cross piece for the handle—costs only 45s. The standard charge for fitting is from 4s. 6d. The Oto jack is really only intended for cars weighing up to 25 cwt. The weight of the complete set is 21 lb., and the car can be jacked up in about forty-five seconds. Three More Types Three more jacks remain in the list of those now on the market—the Stevenson, the Guna, and the Marchal. The Stevenson is another of the type which lifts the car from the side. It is made by Jenks Brothers, Ltd., of Wolverhampton, who have had years of experience with this type of jack. Their latest model is called the Outrigger, and involves special brackets attached to each side member and projecting underneath the running board. A separate jack, of special design, which is carried elsewhere on the car, slides into this bracket, when the car is to be lifted, and is lowered by turning a wheel brace which fits vertically on to the top. Thus, the car can be jacked up without any uncomfortable stooping. This system certainly possesses the merit of simplicity, and is therefore comparatively inexpensive. Prices vary according to the size of the car, from £2 19s. 6d. to £3 19s. 6d. Special brackets are necessary for different makes of cars, but these are obtainable for most of the A 12 | ||