FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1916
1916 - 0359.PDF
AMU- 27. IQI°- (/ycHT THE CHRISTENSEN SELF-STARTER FOR AERO ENGINES. • . little curious that comparatively nothing has been done up The present to simplify the starting of aeroplane engines, and, 'Vh few exceptions, " swinging the prop " is as much the order f the day now as in the ""^ dayS- N°W *at high-powered «>d Irinlc engines are coming more and more into vogue, the subject ""eceivinc more attention from designers, and in this connection •V-est attaches to the Cbristensen self-starter, which has been in lL on automobiles for the past five or six years, and is now being IdaWed for aeroplanes by the N. A. Chnstensen Co., of Milwaukee, Wk U.S.A. This self-starter, which is of the pheumatic type, is The air-compressor of the Chrlstensen aeromotors self-starter for not only light, weighing complete about 40 lbs., but very simple and effective in operation, and compares very favourably with those of the electric type. The component parts consist of a small air compressor and a dis tributor valve worked from the engine, a control valve, a surface carburettor, a reservoir and, of course, the necessary piping The air compressor, which is of the single-cyclinder, single-acting type, is driven from any convenient shaft of the engine—that driving the magneto being, perhaps, the most su'table. It is so coupled to its driving shaft that it can be disconnected at will, as it is not neces sary for it to be running all the time. Air from this compressor is delivered to a reservoir located at some convenient part of the machine, and on its way it has to pass through the control valve, which is situated on the dash in front of the pilot. There are three movements to the control valve lever, (I) starts the compressor (when the engine is running, of course), and opens the communica tion through to the reservoir ; (2) the compressor is put out of action, and the reservoir shut off from the rest of the system ; (3) air is allowed to flow from the reservoir through the carburettor, aud thence to the distributing valve, operated by the camshaft. This distributor is provided with one valve for each cylinder of the engine, and is so timed that the carburetted air is admitted under pressure, to a cylinder on its firing stroke. Thus the piston is ® ® " Aeroplane Design." . , wr v c THE appearance in book form of the paper read by Mr. *. a. Barnwell before the Engineering Society of Glasgow University in the winter of 1914 would seem to be very opportune when, as at present, so many branches of engineering are being drawn into tne aviation industry and when consequently more and more engineers »re taking an interest in aeroplane dewgo. Although the hook is oot-and does not pretend to be—a complete treatise of the subject, Mr. Barnwell-who, by the way, is the designer of the .B™tol Sco« -has been singularly successful in incorporating in his book just enough to give a clear understanding of the general principles 01 -— • - - • •• --• -» of it well aeroplane design and yet keep the mathematical aspect *"thm the gra^p of any non-technical reader possessing a iainy forced downwards, a spark occurs, igniting the charge, and letting the engine in motion. When the engine is running all the parts are out of engagement, consequently there is practically no wear. All the parts are The Chrlstensen sell starter fitted to an 8 cyl. Curtiss aeromotor. of aluminium and chrome vanadium steel, heat treated and ground to a perfect fit, and the lubrication is automatic. The following results were obtained from tests carried out with a Christetwen starter fitted to a Hall-Scott motor at the Sloan Manufacturing Company's plant in Plainfield, N.J. On a tank of air of 250 lbs, pressure, 28 complete starts were made without recharging the reservoir, and the last ttart was made with a pressure of only |iw(nim**f •— , Diagram showing the general arrangement of the Chrlstensen self-starter for aeromotors. 100 lbs. It is stated that the Sloan Company was so impressed with the demonstration that it has been decided to adopt this starter as a standard equipment. It may be of interest to note that the inventor of this self-starter, Mr. N. A. Christensen, it also the inventor of the system of air brakes now in use on the London Underground Electric Railways, Paris Underground and surface lines, and many other continental and American railways. ® ® sound knowledge of the fundamentals of mathematics and mechanics. Should anyone experience difficulty in following Mr. Barnwell's remarks on stability, they will find the chapter on this subject con tributed by Mr. W. H. Sayers of great service. Written in simple, non-technical language, this explanation of inherent stability is lucid enough to be followed lay the veriest tyro in aviation matters. The book is one which will be equally useful to the amateur who wishes to know something about tne theory of flying and to the trained engineer who has not hitherto given any attention to this new branch of science. Moreover, trie price—2*. 6rf.—is within the reach of all. The publishers are Messrs. McBride, Nash and Co., and it may be obtained from '* FLIGHT " Office, price 2s. torf. post free. 359
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
