Patent GB-189923707-A (GB)
Title: Improvements in or connected with Balanced Rotary Steam Engines.
Inventor: LJUNGSTROM BIRGER
Filed: 1899-11-28
Granted: 1900-01-27
Abstract: 23,707. Ljungstrom, B. Nov. 28. Revolving-cylinder type; valves and valve gear.- Relates to rotary steam engines, in which all the moving parts, and the steam controlling - valve, are balanced. There may be two steam cylinders revolving about a central axis and located within a surrounding endless and stationary curved track, which is formed to allow each piston to have two strokes imparted during each revolution, or there may be three orfourcylinders with tracks so formed that each piston has two or three strokes imparted during each revolution. The cylinders are provided with hollow pistons fi t t e d internally with rollers which act upon the stationary track, the steam supply and exhaust being controlled by a stationary valve as shown in Fig. 7. The cylinder ends are slotted, and the pistons correspondingly. The cylindrical steam supply and exhaust valve is shown in Fig. 1, and in central section in Fig. 2. This valve admits and exhausts steam simultaneously, and the admission ports equal in number the strokes imparted to the pistons during one revolution. The valve A is held stationary, by means of a flexible tube F, but in such manner that it is free to follow the vibrations of surrounding parts. Lubrication of the parts is effected by admitting oil with the steam supply. Variation in the supply of steam to the cylinders is along with the adjustment of the valve effected by forming the track with a number of concentric segmental portions at the points where the rollers are in contact when the pistons are in their inner positions. To reverse the engine or to vary the expansion, the arrangement shown in Fig. 13 may be adopted. The sleeve G, which is connected to the flexible connection F, is provided with a collar which fits within a groove between the flange of the casing E and that of the extension G<1>. A lever G<2> attached to the collar partly rotates the valve, so changing the position of the ports. Another arrangement for flexibly holding the valve and allowing for its adjustment is shown in Fig. 15. The interior of the supply end of the valve A is fitted with packing-rings, similar rings being fitted in the steam supply pipe near its joint with the casing. The shaft J passes through the supply tube, and is connected to the valve A by means of a loosely-carried connecting-piece J'. The lever G<2> connected to the shaft J is adjusted by hand or by controlling-mechanism. A cover tube K, Fig. 21, may be fitted over the valve A and be connected with a sleeve and lever K<1> by a tube K<2> joining the two by tongues and slots. Suitable ports are provided in the cover tube K. The levers G<2> and K<1> are placed close together, so that, by rocking the lever G<2>, the valve A is adjusted, and by moving the lever K<1> the cover tube K is partially rotated. Both levers may be actuated from the movement of the lever K<1> alone. By such means the engine may be driven forwards and backwards with equal facility. The steam supply may be controlled, without employing concentric curves in the track, by means of the valve shown in Fig. 26. The valve A is combined with cover blades L, which are rotated by the ring L' embracing the supply end of the valve. The ring L' is rotated similarly to the cover tube K. The central valve, when triplicated, is suitable for an arrangement of triple-expansion engine. The valve bore is tapered, and the ports are in proportion to the cylinder capacity. The steam exhausted from the high-pressure cylinder passes into the interior of the valve and to a chamber formed in the casing, and then to the intermediate cylinder, from which it passes to another casing chamber and to the low-pressure cylinder. The casing may be divided into two parts, or may be without partitions. The cylinders may be arranged in various ways, the axes may be parallel or may intersect, and low-pressure cylinders arranged in co-axial pairs at right-angles, with co-axial high-pressure cylinders arranged between, may be employed to obviate dead centres.