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).
Proposed simple indicator for car battery charging levels to prevent over-charging.
| Identifier | WestWitteringFiles\Q\January1927-March1927\ 86 | |
| Date | 18th February 1927 | |
| TO HS.{Lord Ernest Hives - Chair} BY EFC. } FROM R.{Sir Henry Royce} (At Le CanadelHenry Royce's French residence.) ORIGINAL R1/M15.2.27. DESPATCHED FROM W.W. 18.2.27. X. 4005 X. 4040 C. to DJ. WCR. RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} PN.{Mr Northey} DA.{Bernard Day - Chassis Design} CAR ACCUMULATORS - OVER-CHARGING ETC. For a very long time there has been anxiety to know when the battery is charged. EFC. has produced I understand the Midgeley device in another form which reduces the rate of charge when the volts rise to a certain figure. I am not much in favour of such a device, because - (1) of the increased complication of an already extreme-ly unavoidably complicated system on a car, (2) the difficulty of getting such a device to act with sufficient accuracy. I should like Mr. Northey to give his opinion on this sch. As another scheme I suggested to Mr. Minchin a very simple scheme of closing with unventilated plug one cell, and connecting by rubber or other small piping to a simple indicator (upon the dash) of say 5/8" dia. glass tube with a small nozzle at the bottom for the gas to issue from; it is arranged as a syphon and the glass tube half filled with water or other liquid, coloured or clear, so that when the control cell gases a stream a bubbles pass through the water. This has been made by Peto & Radford and works well on my 7-EX. So far as I can see it should only cost a few shillings and tells the driver when his battery is charged - three advantages:- (1) If it is full (it removes the anxiety about having any charge.) (2) When to stop (prevent distruction and lossof water by overcharging.) (3) It saves nearly all the wear on dynamo commutator and brushes when not charging. We find it worth its place and cost. Is it worth a patent - at least a provisional in England? It is not necessary to see it at night. Will Mr. Northey and EFC. give us their opinions? R.{Sir Henry Royce} | ||