From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Operation and testing of a hydraulic device, likely for suspension or braking systems.
| Identifier | ExFiles\Box 28\1\ Scan100 | |
| Date | 18th February 1927 | |
| Oy3-E-21827 -2- February 18, 1927 (4) Castor oil diluted with alcohol is used instead of glycerine and alcohol (in the Houdaille). (5) The gland packings are of rubber (which is now standard practice on all hydraulic brake systems, etc. which use castor oil) and pressure is prevented from falling on the packings by means of grooves E and F both of which communicate with the reserve chamber. (6) A spring loaded valve at the top of the instrument (not shown) allows the reserve chamber to leak in hot weather if over-filled, at a reasonable pressure of 10-15 lbs. (7) The loads on the spindle are out of balance but actually the bearing areas are very great as the quality of work is such that bearing takes place along the whole back of the vane G as well as the two bronze bushings H and K.{Mr Kilner} Operation. In operation the vane moves say to the left freely until point A reaches B. Then oil pressure lifts valve L and escapes through groove M to the right hand chamber. On the return the oil in the right-hand chamber can only escape through groove M and through the restriction of the eccentric pin D whence it is returned close to the valve N which is open and drawing oil. If the pressure exceeds a pre-determined amount the valve C opens and allows the oil to flow back direct to the L.H. chamber. Since this is the direction of motion for upward movement of the axle this limits the force it is possible to exert on the car when dropping into a hole. On the reverse stroke where only the force of the compressed road spring has to be reckoned with there is no need for a blow-off valve. This makes the instruments right and left-handed. Test of device. The makers claim development tests up to 25,000 miles, and have standardized riding quality tests along the lines of our bumping rig using either bumps or "pot-holes" on the drum. | ||