AT THE HEART OF THE ROAD TRANSPORT INDUSTRY.

Call our Sales Team on 0208 912 2120

A BRAKE ACTUATED BY HYDRAULIC PRESSURE.

29th June 1926, Page 28
29th June 1926
Page 28
Page 28, 29th June 1926 — A BRAKE ACTUATED BY HYDRAULIC PRESSURE.
Close
Noticed an error?
If you've noticed an error in this article please click here to report it so we can fix it.

Which of the following most accurately describes the problem?

A R6sume of Recently Published Patent Specifications.

THE Maybach Motorenbau, of Friedrichshafen, Germany, in specification No. 226,564,,,describe a brake which is operated by means of hydraulic pres sure derived from a geared pump. As with all the more recent developments of such brakes, this firm recognizes the importance of "feel,' which enables the driver to judge the amount of pressure he is exerting on his brakes by the pressure he applies to his pedal, and in their specification they say, "The object of the invention is to provide an arrangement wherein the intensity of the braking effect corresponds to the foot or other pressure exerted by the driver."

An oil pump, which apparently runs continuously, circulates fluid upwards, where it flows through the valve and returns again to the tank. Pressure applied to The valve diverts the fluid so that a pressure is set up in the cylinder which, by means of the piston and rod, applies the brake. The flow of the fluid tends to open this valve so that the pressure in the cylinder is in proportion to the pressure applied to the valve. So far, the plan does not seem new to us, as a device of this type has been made in this country, and was described and illustrated in this journal.

A new departure, however, seems to be the introduction of a spring to the piston rod so that the pressure of the driver's foot can apply the brake inde

• '• pendently of the hydraulic System. This is so arranged that a slight pressure can be brought to bear on the brakes, quite independently of the hydraulic system, which comes into action as the /ring is compressed, as then the arm shown comes into contact with the stem of the valve, which closes if the pressure be continued.

An American Universal Joint.

THE International Motor Co., of Delaware, U.S.A., in specification No., 252,035, describe a universal joint in

which one member is . provided with vanes extending inwardly, whilst the other member has vanes extending outwardly. The spaces between the two sets of vanes are filled with blocks of rubber. A ball bearing of the self-aligning Skefko type is used to centralize the meinbers. The rubber is said to " flow " sufficiently to prevent rubbing between it and the vanes.

This invention does not appear to us to have any very strikingly new points, as it bears a resemblance to the wellknown buffer drive fitted to the R.C. type of Commercar, and we can remember seeing a bearing of this class used to centralize the two members of a clawclutch type of universal joint. Another point which strikes us is that this class of hall bearing does not act truly as a ball bearing unless rotary motion is permitted between the two members, as without this motion the balls merely rub in the outer race, and cannot roll.

Apparatus for Extracting Used-up Lubricant.

THE Standard Oil Co., of America, in

their specification No. 228,870 describe an apparatus for extracting usedup lubricant from the engine cases, gearboxes, etc., of vehicles. The object stated is that the unwanted lubricant can be quickly removed to be reclaimed or otherwise disposed of. The arrangements as set out are such that at a filling station one may have unwanted lubricant removed before refilling with new.

A Winch for Fordson Tractors.

A winch suitable for hauling trucks and other purposes is shown in the specification of G. Rushton, No. 252,058.

The whole of the apparatus is designed so that the front part can be fixed to the forward pin on which the engine is carried, whilst the rear part is clipped to the main axle. The drive is by means of a belt from the drum of the Pordson to the gearing of the winch.

A Brake With a Floating Ring. PALI, HALLOT, of Paris, in his

specification No. 252,227, shows a brake in which the shoes are so formed that there is space enough between them and the drum for the insertion of a floating ring which carries the lining. This ring is not attached to the shoes, but can follow with the drum until it is arrested by an abutment situated above the expander cam. Several applications are shown, in all of which the same floating band is employed.

A Brake Which Will Not Lock the Wheels.

THE Daimler-Motoren Gesellschaft, of

Stuttgart, in specification NO. 252,223, say, "As is well known, the locking of the wheels, especially the front wheels, of a motor road vehicle is liable to have serious consequences, and may result in accidents due to the skidding or overturning of a vehicle." They further point out that the co-efficient of friction between the brake drum and its shoes increases to an appreciable extent with a decrease of speed, whilst the co-efficient of friction between the tyre and the road surface changes only 'very slightly with a change of speed. Owing. to these characteristics, it is difficult for a driver to avoid locking his wheels. .

With the present invention, as applied to front wheels, there is a means whereby the front spring can slide backwards, such as shackles at both ends of the spring. The axle is held in its place by means of the spring shown, attached to the dumb iron.

• When the braking effect approaches the point where the wheels would no longer hold the ground, the spring attached to the dumb iron compresses, and by means of the rod shown closes a valve in the hydraulic system, and by so doing reduces the braking effect.

Tags


comments powered by Disqus