14Patent no。 5,660 (1828); Patents for Inventions, 264。
Figure 11 (above) Badger and Walker’s double ratchet windlass Figure 12 (left) O’Brien’s patent with a roller
Leonidas V。 Badger and Richard Walker of Portsmouth, New Hampshire, obtained a patent for the windlass shown in figure 11。15 Driving and retaining pawls, (A and B), engaged ratchet wheels at either end of the barrel and conventional pawls were fitted in the middle (D)。 Handles were fitted at either end of the rocker-arm (C)。 Their driving mechanism is of simpler pattern than Tyzack’s creeper, but otherwise the windlasses are similar。
James M。 O’Brien of Brunswick, Maine, patented the windlass shown in figure 12, in 1838。16 Driving levers (A) were fitted with roller (B) at one end, sized to match the contoured notches in the ratchet wheel (C)。 At the other end, of the lever, a pin was inserted in one of four holes in the quadrant (D)。 By selecting which hole, it was
15US Patent no。 8,264 (1834)。
16US Patent no。 1,003 (1838)。
Figure 13 Gladstone’s windlass
possible to vary the leverage obtained and thereby alter the mechanical advantage of the levers as they moved to and fro。 One of the levers worked by gravity and the other was pressed against the ratchet wheel by a retaining spring (E)。 Although this design is quite ingenious, we are unaware if it was ever manufactured。
In 1838 Thomas Murray Gladstone, of the firm Gladstone, Eddowes & Co, Liverpool, patented the windlass shown in figure 13。17 It is said the design was chosen because many sailors disliked pump-brake windlasses, preferring the traditional handspike。 A ratchet wheel (A) was engaged by a push pawl (B) and a drag pawl (C), actuated by a lever (D) worked by the handspike (E)。 Because the handspike did not have to be ‘fleeted’ less time was lost, and because the pivot was at deck level instead at the centre of the barrel, the effective length of the handspike was longer, and its purchase was increased by using compound levers。 Four handspikes,
17US Patent no。 7616 (1838)。
Figure 14 Hammond of Boston’s windlass with four pawl cases
turning common shafts (F), two moving up while two moved down meant that heaving in was continuous。 Windlasses of this pattern were successfully fitted to some Liverpool vessels。18
In 1843 Artemus Hammond of Boston, patented the windlass seen in figure 14。19 The pump brakes (A), casings for the creepers (B), four push pawls at (C) and four retaining pawls at (D), are seen in the drawing。 Hammond claimed that because his design had four pawl cases or creepers, rather than two in Tyzack’s windlass, which he describes as ‘the common, or English windlass’, the torsional strain on the barrel was significantly reduced。 Although this concept is carefully thought out, I have no evidence that it went into production。
In 1841 William George Henry Taunton of Liverpool took out a patent for a windlass, shown in figure 15, that used a single athwartships pump-brake lever instead of a pair of fore-and-aft ones, as seen in Tyzach’s patent。20 The pump brakes (A) caused the connecting rods (B) to turn the ratchet (C) by means of the push pawls (D)。 The retaining pawls (E) were secured to the central bitt post。 Figure 16 shows a more complicated version。 The novel feature was the simplification resulting from the way the driving ratchets were shifted towards the centre of the barrel, that allowed both to be engaged by a single transverse rocker andmovedinareciprocating fashion。
Taunton’s drawings are carefully worked out, and in practical terms he may be considered the father of the pump-brake windlass。 However, there are a couple of possible challengers。 In 1838 Master Mariner George Charlton of Wapping patented the windlass shown in figure 17。 Bankruptcy proceedings in 1851 describe him as a ‘windlass maker, and manufacturer of cable and chain’。21In 1842 WilliamCarr 十九世纪锚机的发展英文文献和中文翻译(4):http://www.youerw.com/fanyi/lunwen_96310.html