18i8."] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



30£ 



IMPROVEMENTS IN MARINE ENGINES AND PROPELLERS. 



Joseph Maudslay, of the firm of Maudslay, Sons, and Field, of Lambeth, engineers, for '■^Improvements in ohtaining and applying 

 motive power and in the machinery and apparatus employed therein." — Granted March 8; Enrolled September 8, 1848. [Reported in 

 the Mechanics Magazine.'] 



Fig. 1. 



Fig. 2. 



Fig. 3. 



w 



Fig. 4. 



Fig. 5. 



1. The new steam propeller which forms the 

 leading subject of Mr. Maudslay's present patent, 

 obviates one of the greatest obstacles that have 

 hitherto stood in the way of steam propelling, 

 whether by means of screw blades or flat Wades, 

 or blades of any other description ; viz., the diflB- 

 culty of shipping and unshipping the propeller. 

 Mr. Maudslay affixes the blades of his propeller 

 (which may, he says, be of " ,iny approved or 

 suitable form") in such a manner to the driving- 

 shaft that the propeller assumes of itself, as it 

 were, the proper angle for propulsion, the instant 

 the driving-shaft is put in motion, and returns as 

 instantly into a neutral or inoperative position 

 when the driving-shaft ceases to rotate. 



Fig. 1 represents part of the stern of 3 vessel 

 fitted with tliis improved propeller ; fig. 2, a front 

 view of the instrument detached from its place ia 

 the vessel; and fig. 3, a sectional plan of the 

 propeller, and its connections on the line a 6 of 

 fig. 1. 



"A' A^ are the blades of the propeller, which 

 are inserted at their inner or narrow ends into 

 sockets B' B-, in the end of the propeller-shaft S, 

 in which sockets they are free to turn to the ex- 

 tent to be presently defined. To the shank of 

 each propeller blade there are two toothed seg- 

 ments C' C, C- C-, attached one at the top of 

 each socket, and the other at the bottom of 

 it ; and the two sets of segments work the one 

 into the other within the limits determined by 

 the stops/./; so that the propeller-blades must 

 always move in perfect unison, and can only turn 

 round in their sockets to the e.\tent allowed by 

 the stops. E is a sliding clutch, affixed to the 

 driving-shaft inside of the propeller-blades, «hich 

 may be moved sternwards, so as to lay hold of 

 either of two sets of pins, d d and e e, which pro- 

 ject from the back of the wheels of the innermost 

 propeller-blade A-. F is a vertical rod, by means 

 of which tlie clutch E, may be worked from the 

 deck of the vessel; this rod terminating at bottom 

 in a screw, which takes into a swivelled nut ra, 

 which is attached to one arm of a bell-crank G, 

 the other arm of which is forked so as to embrace 

 the clutch E, when brought down upon it. The 

 mode in which the propeller, as thus fitted, acts, 

 is as follows :— Supposing the clutch to be disen- 

 gaged, and the driving-shaft to be put in motion, 

 the blades are immediately throH n out into the 

 angular positions proper for propelling, and they 

 will continue in these positions as long as the 

 shaft continues to rotate. Should occasion arise 

 for backing the vessel, the blades are then se- 

 cured in their extended positions by interlocking 

 the clutch with the pins d d, at the back of the 

 wheels of the innermost blade A-, as represented 

 in fig. 3. When the engine is stopped, and the 

 driving-shaft ceases to rotate, and the clutch is 

 withdrawn, the propeller-blades vvill, by the action 

 of the water upon them, be turned round in their 

 sockets until they come into a line with the course 

 of the vessel, and present their sharp edges only 

 to the water, as exemplified in fig. 4 ; and, for 

 greater security, they may be made fast in this 

 position by interlocking the clutch E, with the 

 pins e e, at the back of the wheels of the innermost 



blade." 



From the instantaneousness with which this 

 peculiarly fixed screw propeller can be turned 

 to account, from its never being required to be 

 raised out of the water, and never oftering, when 

 in the water and at rest, any material obstruction 

 to the steering or progi-ession of the vessel, it 

 seems to possess so far a great superiority over 



40 



