Preventing Uneven Wear on Brake Facings
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AFLEXIBLE shoe, which can be applied at several points around the brake drum, is the chief feature of a design of brake shown in patent No. 510,440, by W. Tucker, Ash Green, Radnage, Bucks. Dealing first with the operating mechanism, a rotary collar (2) can be moved angularly by a cable attached to the pedal. Connecting rods (5) transmit the motion to sliding wedges (1) which force apart slidin g plungers located between the shoe ends. The uniform distribution of pressure is brought about by the use of pivoted struts (3) ; these apply the force at four points on each shoe, the shoes being made of strips of spring steel. A pair of anchor pins (4) serve to locate the shoes-when in the " nfl " position, hut they are flexible enough to allow slight tangential movement during operation.
Power-assisted Injection Pump Timing Adjustment.
adjust the injection timing of an engine while running requires considerable effort, and a scheme for the power-assisted performance of this operation forms the subject of patent No. 510,415, by L. Gardner and Sons, Ltd., Barton Hall Engine Works, Patricroft, Manchester.
The device is made to respond to the pressure of the cooling-water flow, and it is claimed that this pressure varies at about the same rate as that required for correct injection. The drawing shows the layout of the scheme in which a pipe (1) is taken from the pressure side of the water pump and led to a cylinder (2) containing a spring-loaded diaphragm. The diaphragm works the lever (3) which controls a helically splined coupling in the pump drive.
Should a different regulation from that given by the water-pressure be required, a second scheme, employing a formed cam, is also described. An Elevating Tailboard Platform to Facilitate Loading.
TO facilitate the loading and unload ing of a lorry is the object of a scheme shown in patent No. 510,019 by H. Shonnard, New Jersey, U.S.A. The proposed apparatus consists of a means for raising and lowering a rear platform which may normally do duty as the tailboard.
In the drawing, a pair of H-section members (1) are attached to the body, and provick., a track for a pair of sliding rods (3) and their counterweights. The platform (4) is pivoted and chained to these sliders, and can be lifted to the level of the body floor by a pair of cables. A battery-driven electric motor (2) provides the power via a two-speed gear, although a handle is also fitted.
A Cast Crankshaft with Cored-in Oil Passages.
ADESIGN for a crankshaft suited to being manufactured from a casting, is shown in patent No. 510,655, by G. Meyer, Berlin. The chief feature is that the oil passages are so arranged that they can be cast in, instead of being drilled as heretofore. The draw
fag shows a section of two crankpins and the connecting web, the latter being in the form of a disc. Each bearing is cored with a cigar-shaped hole, the ends of which are open to the web. A circular brim (1) around the web traps the oil and prevents its escape except via the big-end lubricating ports (2). The patent does not mention the means for supplying oil, but it is presumed that it is pressure-fed to the main bearing.
A Novel Principle in Carburetter Design.
ACARBURETTER in which th. fuel is vibrated into a mist befor meeting with the air stream, is showi in patent No. 508,582, by Bran
denburgische Metallverarbeitung G.m.b.H., Berlin. The mist thu formed is treated as a gas and fed to ; mixing valve for dilution with air. .
The fuel is agitated at a high fre quency by what is known as a " piezo electric crystal," that is, a crystal tha will vibrate when excited by an electri current. The crystal (5) is housed a the bottom of a taper tube (4) and i supplied with current via a contact (6 and an earth return. Petrol from normal type of float chamber rests o: top of the crystal, and when the cm rent is switched on, the vibration heap the fuel into a conical mist, the lightt parts of which pass through a filter (3 and reach the air-mixing valve (2) The purpose of the small air-inlet (1 is to carry the fuel towards the mai air-valve.
The vibratory frequency of the cry: tal is well into the supersonic rang( being of the order of 300,000 cycles p( second.