807,647. Rotary engines. WALTER, H. Nov. 22, 1955, No. 33381/55. Class 110 (2). [Also in Group XXXII] A rotary engine 1 with an inner pressureresistant casing 2 forming a working chamber 3 and a combustion chamber 4 closed by endplates 5, 6 is provided with a common duct 7 divided by a thin partition 8 into suction inlet 7a and exhaust outlet 7b. Separate ducts may be used if they are kept in constant communication. Vanes 7c divide exhaust outlet into sections, and in use air is drawn into the exhaust from the inlet to cool the exhaust. Air may be supplied to the suction inlet at atmospheric pressure as in Specification 807,648 or at higher pressures by means of a blower. A conduit 9 leading to inlet 7 and divided into an inlet passage 10 and outlet passage 11 is secured by bolts 12 which hold a spacer 13 against a yieldable seal 14 for a cooling jacket 15 surrounding the casing 2, the seal 14 also taking up any change in the casing 2 due to temperature variations. The coolant may be water passing through inlets 19, 20 and outlet 21, a valve control (not shown), being provided so that flow is greater on the exhaust side of the casing. A driving piston 25 is fixed on a shaft 23 mounted in bearings 23a, 23b in the closure plates 5, 6 respectively. Parallel with shaft 23 is a shaft 24 integral with an abutment 26 and provided with annular collars 24a, 24b having press-fit with annular bearings on hollow axles 24e, 24f respectively supported in the plates 5, 6. Shaft 24 is also provided with guide bearings 24g, 24h and gears 122, 123, Fig. 3, are mounted on shafts 23, 24, respectively, beyond the plate 6, the gears being connected to means for adjusting the clearance between piston 25 and abutment 26. The chambers 3, 4 are cylindrical and are connected by a passage 22 cut back as in Fig. 1 to prevent the formation of pockets of high or low pressure. Fig. 7 illustrates the design of the chambers 3, 4, piston 25 and abutment 26. The chamber 3 has an arbitrary diameter D and a concentric circle has diameter D<SP>1</SP> corresponding to the maximum diameter of piston 25. At a distance R from the common centres is the centre of a third circle touching the inner circle and having diameter D", which is the diameter of chamber 4. These circles are used to determine the shapes of the piston and abutment, as shown in Fig. 7, where areas K and L respectively represent combustion space and compression space. A modified design for the chambers is also described. The abutment 26 has a casing 28 welded to the body 27 within which body are chambers 29, 30, Fig. 1, in communication with passages 38, 39 and passages 33, 34 leading to cooling passages 31, 32. Coolant entering a chamber 44, Fig. 2, through an inlet 45 enters these passages through an inlet 35 and is returned by passages 42, 43, 41, 40 to an outlet 36 and thence to a sump 46. Pressure equalizing bores 49 extend through the body 27 parallel to the shaft 24. Sealing lands 52, Fig. 4, are provided at the ends and sides of the abutment 26, which also has cut-out corners 53, 54 to improve the seal. The piston 25 has a similar construction. to the abutment 26 having an outer casing 61 on the body 60 which is keyed to the shaft 23. Within the bore of shaft 23 is a flexible shaft 73 with one end 74 splined to shaft 23 and the other end 75 splined to a relative motion damper 77 having an outer element 78 fixed to the gear 122. Shaft 73, which is keyed to a power take-off 82, rotates with shaft 23, the damper 77 serving to cushion shocks between the shafts. Coolant enters the annular space 84 between shafts 23, 73 from a chamber 87 having a supply inlet 88. After passing through passages similar to those in the abutment 26, the coolant is conveyed through longitudinal channels 64, 65, Figs. 1 and 2, to annular passage 85 and passes thence to sump 46. The damper 77, Fig. 11, has an inner element 76 with slots 110 in which slide vanes 113 projecting into the outer element 78, each vane having a through passage 116 for coolant entering the slots 110 to pass into chambers 111 connected by passages 118, through which the fluid is driven by the movements of the vanes. Extending into each passage 118 is a throttle element 120, Fig. 13, which can be adjusted to restrict the relative motion between shafts 23 and 73. The driven gears 122, 123, Fig. 3, mesh with idlers 124, 125 mounted on pivoted arms 126, 127 so that adjusting these arms by means of screws 130, 131 and pins 140, 141, the clearance between the rotors 25, 26 can be controlled. The idlers 124, 125 are then fixed by a spacer bar 144. Meshing with idler 124 is a pinion 150 keyed to a shaft 151 operatively connected to a fuel pump 152, Figs. 1, 3, connected to a fuel source through a conduit 154 and filter 155. Pump 152 is connected by conduits 157, 158 to a pilot injection valve 159 and main valves 160 opening into the combustion chamber to inject fuel twice in each revolution of the rotor 25. A spark-plug 162 mounted in the casing 2 has current leads 164 and the pilot valve opens into a flame-holding recess 165 to provide continuous combustion in the chamber 4. A pump (not shown) connected to return outlets 170, 171, 172 is used to supply the cooling and lubricating fluid and is connected to pressure seals 190, 191, 192, 193. This pump may be driven from one of the idler gears and supplies inlets 45, 88, 173-180. The seal 192, Figs. 2 and 9, comprises a sleeve 200 having shrink fit on the shaft 23 and supporting a slidable collar 203 with lands and grooves 204 to form a labyrinthine seal. Sealing-rings 205a ... 205f supported by the sleeve and collar have communicating passages 206, into which fluid enters from a passage 194. This fluid leaks into a chamber 208, excess fluid being forced out of the chamber to passage 211 and thence to the sump 46. The collar 203 is connected to a rod 220 slidable in a bore of the casing. The seals 190, 191, 192, 193 are identical in construction and as the shafts 23, 24 rotate the respective sleeves 200 also rotate, but stop-pins 225, Fig. 2, prevent the collar 203 and ring 205a rotating. The intermediate rings 205b ... 205e therefore rotate at a fraction of the speed of the shafts. Initial rotation of the shafts 73, 23 by means of coupling 83 drives the rotor 25 and gear 122 which through idlers 124, 125 drives the gear 123 to rotate the shaft 24, and, with it, rotor 26. As rotor 26 passes the pilot valve 159, fuel is injected into chamber 4, which is ignited when the rotor uncovers the ignition plug 162. U.S.A. Specification 1,003,263 is referred to.