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).
LaSalle steering systems, gear load capacity, bearing efficiency, and handling stability.
| Identifier | ExFiles\Box 170\2\ img242 | |
| Date | 12th January 1935 guessed | |
| -4- The combination of zero camber and a front stabilizer with say a 5 lb increase in pressure, gives normal front tire life. LaSalle Steering The front weight of the LaSalle is not 2400 lbs but about 2125 fully loaded. However Marles are completely wrong in saying that the LaSalle steering is inadequate for these loads. They must be basing their statements on their original design and heat treatment, etc which are not a patch on current Saginaw practice. As I have picked up the information around here, the original gears were like the sketch attached. Radial thrust on the roller was taken on a plain bushing. There was some cocking action on the roller. Later, needle bearings were tried. Efficiency was gradually lifted from 45% to 60%. Needle bearings on the driven spindle gave 70% efficiency. The double contact tooth and angular contact ball bearing raised the load capacity and efficiency. Efficiency went to about 75%. Angular contact ball bearings straddle mounted on the driven spindle are capable of giving us 88 to 90% efficiency. The load capacity of gears of a given dimension has increased two or three times in the last few years and a special shock-testing rig which whirls an unbalance weight on the end of the pendulum lever as the gear is swung back and forth through its range has led to an improvement in life of about 800%. Kettering's legend of the long lever, is that a steering mechanism is a lever of which the driven half is 8" long and the handle is 10 feet to 14 feet long. The gear is the part of the lever around the fulcrum, and is a place where stresses are necessarily high and displacements low. The double tooth, increasing the range of the gear, is exactly equivalent to increasing the whole size of the gear in reducing the stresses. The contact being on the outside of the teeth reduces the effective helix angle and accounts for our figure of 5 degrees - 57 as against yours of 7.4 degrees. Handling stability Suppose a car is proceeding straight (see sketch) and for any reason | ||