Keeping Warm
Page 63
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rOMING of warmer weather prevented The
Commercial Motor from testing the effectiveness of the Jenheat anti-freeze unit, .a device for heating water in an engine's cooling system, but it is understood to have been satisfactorily tried by a•number of fleet owners during the winter.
The unit is claimed to be able to raise the temperature of 1 gal, of water through the 6° F. range in 21 hr., representing an overall efficiency of 65 per cent.—a figure ,which could be improved by muffling the radiator to prevent dissipation of heat.
A more powerfuLunit is made for .oil engines with large radiator ca,pacities. Both cost £45s. The makers are Jenbro Products, 43 Plough Road, London, S.W.I I. Export inquiries should be addressed to Gelmar and Co., Ltd., 4 Rangoon Street, London, .E.C3.
Inbuilt "Policemen" I-1 A DEVICE for preventing vehicle
theft and another to stop drivers from speeding have been developed by Mr. E. J. Rateliff, 97 Hay Lane, London, N.W.9. They are shortly to be marketed each at a price estimated to be about £15.
The anti-theft unit consists of a valve introduced into the braking circuit to be screwed down, when the foot brake is depressed, to hold on the brakes while the • vehicle is left unattended by maintaining hydraulic pressure. Whilst there is nothing new in this princiftle, novelty lies in the enclosing of the valve in a heavy casing with a removable lid.
The lid may not be opened or removed without the use of a key, and to prevent conspiracy involving the copying of the key, it is envisaged that the lids •be changed from one vehicle to another day by day. At intervals, the user would exchange a set of lids with the supplier for a number of new ones requiring further different keys.
Mr. Ratcliff offers his other invention as an alternative to a carburetter governor, and states that his design allows full engine power to be.. availed of when necessary. Its essential component is a rod which is caused to move by the action of centrifugal balance weights, which are driven by connection with the speedometer cable.
Other components are a solenoid' operated butterfly valve in the induction manifold and a dashboard control with settings for 30 m.p.h. and 40 m.p.h. (the second being provided chiefly for operators of vehicles not always sub-, ject to 30 m.p.h., light 4 x 4 models, for example). As the vehicle gathers road speed, the rod is raised by the weights, and according to the setting of the control an electric circuit is joined when the specific speed is attained, a contact on the rod meeting another fixed to the housing.' Current' flowing through the circuit then operates' the solenoid to close the valve, thus depriving the engine of mixture.
. Throttle openings appropriate to need are possible in any gear so long as road speed does not exceed either 30 m.p.h. ' or 40 m.p.h. However, should sudden over-riding of the apparatus be necessary in traffic, the accelerator may be fully depressed, which action causes another switch to isolate the system by Creaking the circuit.
John Bull Giant A VAILABLE in a range of popular sizes, a giant tyre introduced by the John Bull Rubber Co., Ltd., Leicester, has a rayon carcase, a wide tread and a pattern with continuous ribs. It is intended for use on vehicles operating at sustained speed on modern roads.
Plasticized Fabric Sheet Pl.A MATERIAL which, it is claimed, could make it possible. to produce from plastics components of complex shape which are commonly pressed from metal sheet has been introduced by Leicester Lovell and Co., Ltd., North Baddesley, Southampton. Known as Resnit, it is in the form of dry semi-rigid sheets of resin-impregnated fabric which can be formed under heat and moderate pressure.
Tools used for pressing components in Resnit may he similar to those used for forming metal, except that they can be lighter and provided with means for heat
ing to a temperature of about 160' C. Pressures are normally in a range of 100500 p.s.i. and press cycle times are at present 14-2 min., but it may be possible to reduce these by shock curing: Characteristics possessed by Resnit when softened by heat enable it to be shaped into forms which could not be taken by metal. It is not expected that, even in large quantities, the material cost of Resnit could equal that of ordinary mild-steel sheet, hut the plastics offers other advantages which might enable it to compete. Cost comparison with light alloy and glass-fibre reinforced polyester resin laminates appears to be favourable.
Among the immediate applications foreseen for Resnit are body components and panels, interior fittings and cartons.
Tester Approved
'FHE Don Mark III brake meter, made
by 'Bowser, Monks and Whitehouse, Ltd., and sold by 'Small and Parkes, Ltd., Hetidham Vale Works, Manchester, 9, has been approved by the Ministry of Transport for use as brake-testing equipment in the forthcoming vehicle eXamination scheme. The meter itself costs £8 12s., whilst the floor-mounting stand which is required by the Ministry is £4.
No Slipping ENABLENABLING vehicles to drive mit of ING whereas they would otherwise spin their wheels, Car-Shue mats are being sold by Messrs. Berrisford and Booth, Broadstone Hall Road South, Reddish, Stockport. They are made of expanded metal and are placed under the driving wheels so that drive can be transmitted without slip, and can be attached by rope to the vehicle so that they are easily retrieved after use.
The price is £4 7s. 6d. for the type suitable for small vehicles and £4 9s. 6d. for a larger pattern_ Sizes for commercial vehicles, including those with twin tyres, are also available.
Process Take-over THE Canusa continuous-extrusion proI cess, by means of which parts made of phenolic moulding powders can be produced to compete with metal components, has been taken over by Sterling Moulding Materials, ,Ltd., 8 Heddon Street, London, W.1. A new factory is in operation in Cheshire and the original Can usa unit has been moved to there.