Improvements in
Page 62
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Engine Mountings
AN interesting modification to the usual type of resilient engine mounting is shown in patent No. 418,863, by L. Gardner and Sons, Ltd., the well-known enginemaking concern of Barton Hall Engine W orks, Patricroft,
_Manchester. The specification points out that whilst rubber bushes satisfactorily absorb most vibration, conditions may occur in which the frequency of the engine vibration may coincide with the natural frequency of the suspension, which would result in an excessive vibration at one particular speed.
To overcome this, it is proposed to add a frictional clamping device to the system. As in normal practice, the engine bracket (1) is carried on a rubour bush (2), but in this case the central bolt is extended to carry a metal drutn (3). Around this drum is a split hearing (4) lined with friction material, and clamped together by spring-loaded bolts. The action of this device is to resist motion irrespective of frequency, in the same manner as the dampers used on springing systems.
The Analysts of Exhaust Gases.
IT is usual practice in large industrial 'boiler plants to keep a careful check on the constituents of the waste fluegases, as this forms an accurate indication of whether the fuel is being burnt to give its maximum usefulness. Patent No. 416,944 describes an instrument for similarly checking the exhaust products of a vehicle engine: the inventor is E. Bennett, 57, Moorfields, Liverpool.
The action of the instrument depends on the different thermal conductivities of air and carbon dioxide, the latter being the correct effluent from an oil engine. Two tubes, one containing air and the other exhaust gas, have each within them a small spiral of wire, slightly warmed electrically. The different cooling effect of the two gases alters the temperature of the two wires, which in turn, causes its resistance to
be slightly varied. By an arrangement similar to a Wheatstone bridge the difference in resistances is made visible to the driver by a pointer on a scale calibrated " Weak—Normal-Strong."
*B48 A Variable-speed Transmission.
PATENT No. 417,624, from the Reo Motor Car Co., Lansing, Michigan, U.S.A., describes a variable-speed gear in which the ratio is controlled by the speed. The drawing shows a section of the gear, in which the driving pinion (4) meshes with a rack-ring, which is confined by a clutch to one-way rotation. This, in turn, meshes with the .driven member (I). At slow speeds the central pinion drives this member at a reduc,,I speed, but, as this increases, a
resistance to the rotation of the ring • (2) is provided by out-of-balance weights attached to pinions (3). When the speed of rotation is increased to a certain amount, the driving torque ceases to overcome the centrifugal resistance of these weights, and the whole gear rotates as one.
A Speed Synchronizer for Gearbox Use,
PATENT No. 4143,650, by Societe Anonyme Adolphe Saurer, Arbon, Switzerland, gives details of an arrangement of friction clutches for the purpose of equalizing the speeds of two gears about to be engaged. The drawing shows a portion of a gearbox of the constant-mesh dog-clutch type. The central splined dog member (2) can be slid either to the right or the left to engage the corresponding gear. The special feature is the provision of a loose ring (3) mounted on a tapering boss, and having dog-teeth (4) projecting beyond the main dog-teeth (1).
When the sliding sleeve (2) is moved towards engagement, these projecting teeth take up the drive _before the main teeth, and so revolve the ring (3). Further sliding inovetnent causes the conical clutch to bring the sliding sleeve (2) and the shaft to the same speed as the driving dog, and, thus, final engagement may be made without shock, k A Novel Type of Clutch.
r'r1-1E claim is made for the type of A clutch shown in patent No, 416,434 that it can be made of a much smaller diameter, having regard to the torque transmitted, than the usual type of friction clutch. The patentees are J. Zarb, 24, Mervan Road, London, S.W,2, and three others. The drawing shows an internal cone (4) and the corresponding external cone (3). The unusual feature of this design is that the former is eccentrically mounted on its splines, so that when it enters the external cone this also tends to run out of truth. This is permitted to a limited extent by the special manner in which the external cone is fixed to the flywheel, being supported on pins (2) in oversize holes (1). The outer clia,meter of the internal cone is made in the form of a thin rim ; this is intended to spring in and so accommodate the remainder of the cone's eccentricity.