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 'Automotive Industries' magazine discussing new methods of chassis lubrication, including oil-less bushings, direct feed, and wick feed systems.
| Identifier | ExFiles\Box 76\4\ scan0141 | |
| Date | 28th February 1918 | |
| AUTOMOTIVE INDUSTRIES THE AUTOMOBILE VOL. XXXVIII NEW YORK—THURSDAY, FEBRUARY 28, 1918—CHICAGO No. 9 446 AUTOMOTIVE INDUSTRIES THE AUTOMOBILE February 28, 1918 New Methods of Chassis Lubrication Designs for Minimizing Attention and Increasing Life of Parts—Advantages and Disadvantages of Oil and Grease Lubrication—Oil-less Bushings—Direct Feed and Wick Feed Systems By Cornelius T. Myers WHEN we speak of chassis lubrication we refer to the lubrication of such minor parts of an automobile as spring bolts, brake connections, universal joints, radius rod connections, steering rod joints, etc., which form connecting links between the more important units of the chassis. Lack of proper lubrication at these points is not immediately evident in the performance of a motor vehicle, whereas lack of lubrication in the engine, gearbox or axles makes itself felt in a very short time; hence, comparatively little attention has been paid to the lubrication of chassis parts and their durability and efficiency have suffered. These parts also are in more or less inaccessible locations, and the importance of their proper lubrication has been lost sight of. Rightly, the lubrication of these parts should have been more carefully considered, in the light of the important function performed by them, and especially on account of their comparative inaccessibility. Wear at these points is almost always due to improper or insufficient lubrication, and this wear is responsible for squeaks, rattles, emphasized vibration, and break-down to an extent only appreciated by an experienced garageman. The summation of small amounts of wear in many parts accounts for many chassis troubles, quite a few of which have been wrongly interpreted in the past. Major parts of the complete machine have been called upon to work under improper conditions and their design often has been adversely affected by these conditions. Important Units Receive Attention In gearboxes we have an instance of careful thought for lubrication in an inaccessible position. The details have been carefully worked out so that, under ordinary conditions, one filling with moderately heavy oil per year will suffice for satisfactory service. The same comment applies to rear axles, so far as the lubrication of parts in the housing is concerned. The general plan in these cases is that of retention of lubricant and exclusion of dirt, to which method the design and operation of these parts lend themselves. The lubrication of engines has been given careful and constant attention until very reliable systems have been developed. These systems are all based upon a continuous wastage of lubricant and the partial exclusion—partial removal—of foreign matter. It is upon this principle that the lubrication of most chassis parts must be handled, involving more or less continuous flow of lubricant. The more continuous this flow when the vehicle is being operated, the more efficiently will the bearing surfaces be lubricated, other things being equal. This being the case, care must be exercised to see that dirt or other non-lubricating matter is not picked up and led to the bearing surfaces. Choice of Lubricant for Chassis Parts The most important consideration in the design of the chassis lubrication devices is the choice of lubricant. Shall grease or oil be used? Each has advantages and drawbacks. Grease is stiff enough, as a rule, to be more cleanly than oil and not flow over painted surfaces near the grease cups. It lends itself to compact and simple design of cups integral with spring bolts, and its firmness allows grease cups to be set at an angle or even in an inverted position, which is often very convenient where holes for the cups must be tapped in restricted locations. Some claim that grease will support heavier bearing loads, but the difference is probably more apparent than real. Grease can be forced by hand screws from the cups to the various surfaces. In hot weather the heavier greases are possibly more cleanly to handle than oil with the ordinary chassis fittings. On the other hand, grease must stand under heavy in-third or even fourth; as in a steering gear, oil can be successively used on the thrust collar, the actuating mechanism and the trunnion bearing, and then led out and down the steering arm to the ball joint on the drag link. The lubrication of universal joints has always been an unsatisfactory proposition. Oil is the best lubricant, but great difficulty has been encountered in retaining it in the casing of the joint for more than a short time. Hard grease is easily retained, but is a poor lubricant at these points, especially in cold weather. A medium grease is most used, but it is far inferior to oil for the same reasons as were given for other chassis parts. One of the illustrations herewith shows a method devised by the writer for magazine lubricating a universal joint by drawing small amounts of oil intermittently from the gearbox, clutch case or rear axle. If the oil ultimately escapes, as it will in the ordinary joint, it will be in very small amounts and will make little difference. It can be so arranged that a part of the escaping oil will lubricate the slip joint. This is very important, especially with machines that use the Hotchkiss drive, where there is a considerable movement at the slip joints. If this last point is well lubricated, a serious end thrust will be put upon the universal joint and on the bearings behind it in the gearbox. Advisability of Spring Lubrication There is some difference of opinion as to the advisability of lubricating a spring. The magazine system leads the surplus oil from the spring bolts to the spring leaves. This prevents rust and eliminates squeak. It maintains the flexibility of the spring at approximately that given it by the spring maker, depending upon the amount of oil fed to the spring, its distribution between the plates, and the manner in which the plates are formed and fitted. When the flow of oil to the spring bolts is properly regulated, there is not sufficient oil led to the leaves of the spring bolts to destroy its interleaf friction, for the high spots between the leaves break through the oil film and there is metal to metal contact—but without squeak and without accumulation of rust. Labor Shortage Calls for Automaticity To-day in every line we need devices that require the minimum of attention and serve their purpose with the greatest reliability. The passenger car and motor truck of the immediate future must offer these advantages, for they will be called upon to serve more constantly and there is surely going to be a shortage of chauffeurs and garage help. Women now drive their cars and should be able to care for them, when necessary, with but little assistance. Women will be called upon more and more to handle delivery cars and light trucks, relieving the shortage of men as they are called in greater and greater numbers to our armies. The men left in the garages will have less time to pay attention to detail, for they will have to look after more machines. The little troubles that so often cause annoyance and breakdown are largely due to lack of lubrication, and as a fighting nation we cannot afford them. By the provision of lubricating devices as described they can be avoided. | ||