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).
Design and specifications for a centralised chassis lubrication dashboard pump.
| Identifier | WestWitteringFiles\T\January1929-February1929\ Scan149 | |
| Date | 15th February 1929 | |
| BY.{R.W. Bailey - Chief Engineer} ) FROM DA.{Bernard Day - Chassis Design} HS.{Lord Ernest Hives - Chair} ) C. to WOR.{Arthur Wormald - General Works Manager} E.{Mr Elliott - Chief Engineer} ORIGINAL DA{Bernard Day - Chassis Design}2/M15.2.29. CENTRALISED CHASSIS LUBRICATION - DASHBOARD PUMP. X3806 With reference to HS{Lord Ernest Hives - Chair}1/LG5229., we have prepared a design for a pump of larger capacity with higher pressure - N. sch. 2830. - send herewith, to avoid the possibility of delay, but we are not quite clear as to the necessity for it. Our information (which may be out-of-date) is that the pump used on the American chassis is the hand operated one, the particulars of which, from drawings and Mr. Bijur's information, are:- Bore & stroke .650 dia. X 2.750". Capacity .912 = 14.94 c.c Pressure per sq. in. 60 lbs. This pump worked satisfactorily. As compared with it our pump has been relieved of 5 rather thirsty components viz: Front axle. Universal Joint & torque sphere. Rear axle. Front & rear springs. So that Mr. Royce's wish to make the pump smaller seemed justified. The recent proposal to include the road springs in the centralised chassis lubrication forms a possible reason for an increase now. Actually the corresponding particulars of the RR. pump as designed (N. schs. 2647. & 2736.) are - Bore & stroke 1.250 dia. X .750. Capacity .92 cu. ins. = 15.07 c.c. Pressure per sq. in. (N. sch. 2736.) 82 lbs.) Max: originally 60 lbs.) (It will be seen that our capacity figures do not exactly agree with HS{Lord Ernest Hives - Chair}1/LG5229.) So far as we are aware the Bijur foot operated pump has not been used on a RR. chassis. (Our information regarding it is as follows) - Bore & stroke 1.5 X .7". Capacity 1.236 cu. ins. = 20.22 c.c. The pressure we do not know but take your figure of 124 lbs. per sq. in. giving a load of 219 lbs. and a spring stress of 166,000 lbs. per sq. in. Mr. Bailey objects strongly to our exceeding 80,000 lbs. per sq. in. because the resulting springs cannot be guaranteed. One would not have concluded from the 10,000 mile test report on the centralised chassis lubrication that more capacity or more pressure was required, all bearings in connection with the system being apparently well oiled. (1) | ||