GB326397A - Steam turbine spur-gear power-box for stoker drive - Google Patents

Abstract

326,397. American Engineering Co., Feb. 21, 1929, [Convention date]. Mechanical stoking. - A mechanical stoker is driven from a steam turbine through a variable-speed gear box comprising chain gears with special tension means and pressure lubricating devices. The stoker is connected to a driven shaft 4, Figs. 1 and 6, extending through the side walls of the housing of a power box 11 and carrying a large gear wheel 14 which meshes with a pinion 15 on a shaft 16. The shaft 16 extends through the side wall and carries at its outer end a gear wheel 18 meshing with a pinion 22 on a sleeve 23 loosely mounted on a high speed shaft 24. Arms 32 on a sleeve 25, keyed to the sleeve 23, afford a mounting for a non-rotatable spindle 33, carrying loosely mounted planet gears 34 and 35. These mesh with internally toothed gears 36 and 37 either of which can be locked by turning the handle 44 of the cam shaft 43, Fig. 11. The planet gear 35 meshes with a gear wheel 45 on the high speed shaft 24, the whole forming a variable speed device as described in Specification 309,341. A steam turbine 46 is mounted on the upper portion 47 of the housing, Fig. 5. A gear system 49 comprising a driving pinion 86 mounted on the turbine shaft extension meshing with a large gear wheel 88 keyed to a tubular shaft 89 is enclosed in a chamber 66. Another chamber 67 houses a sprocket wheel 112 on the high speed shaft 24, the two being connected by a chain 111. The shaft 89 is mounted on eccentric end portions 93 and 94 of a jack shaft 95 which can be turned by an arm 103 with micrometer adjustment. A chamber 119 forms a reservoir for oil and is connected by a plurality of apertures to the chamber 85 and thence to the chamber 66. The free passage of oil from chamber 66 to chamber 67 is prevented by a cover member 127; a small amount required for lubrication passes into the chamber around the shaft 89. The accumulation of oil in 67 is presented by a resilient plate 129, Fig. 9, provided with a bevelled scraping edge in contact with the chain 111, surplus oil being taken off the chain and led back to chamber 66 by the pipe 144. An oil pump 153 may be bolted to the cover plate 127 and driven by a chain mechanism 155 from the tubular shaft 89. The gear system 49 and chain mechanism 155 are lubricated, by the revolving plate 160 which receives the oil forced from between the gears 49 and 86 and throws it out by centrifugal force. The top of the chamber 66, the cover member 127 and the pump 153 are enclosed by a cover member 162 provided with a removable plate 166 for access to parts within. The suction and discharge pipes of the oil pump extend through openings in the rear portion of the chamber 67, the suction pipe terminating in the valve plate 174, Figs. 5 and 7, in the side wall of the oil reservoir 119. The oil enters by a slotted pipe 178, the ball valve 177 preventing a reverse flow. The pipe 178 is surrounded by a tubular cooling. coil 180 and the whole system is enclosed in a tubular screen 186. These parts form a detachable unit extending into the oil reservoir. A pressure pipe from .the pump leads to a distributing manifold 191 in the upper portion of the main housing, the pressure being controlled by a bye-pass valve 203. The governor of the turbine is so adjusted that when the valve 203 is fully opened the speed of the turbine is greatest and vice versa. In operation, if the handle 44 be moved from its mid-point to the right or left, the speed of the shaft 4 is decreased or increased.