US3759640A - Rotary engine valve means - Google Patents

Abstract

This invention provides a valve system for directing charges of pressurized working fluid into the expandable chambers of a rotary engine, for operation against a pivoted power arm associated with each chamber. The valve system includes a manifold for containing a supply of pressurized working fluid, and fluid intake ports associated with each expandable engine chamber. Fluid conduit means associated with each intake port communicate with the manifold, and valve means associated with each port are adapted to open or close the conduit means in a timed sequence. Cut-off means also are provided to stop the flow of working fluid to the engine chambers after the power arm associated with each port has moved through a selected portion of its power stroke. Switching means also may be included to selectively switch the rotary engine between simple and compound modes of operation.

Description

United States Patent 1 Hinckley et al.

[ Sept. 18, 1973 ROTARY ENGINE VALVE MEANS [75] Inventors: John N. Hinckley, Beloit; Van Tassel Stonehocker, Brookfield, both of Wis. [73] Assignee: Beloit College, 'Beloit, Wis.

[22] Filed: Apr. 1, 1971 [21] Appl. No.: 130,182

[52] US. Cl 418/249,-137/625.11, 137/625.15 [51] Int. Cl. F0lc l/00, F03c 3/00 [58] Field of Search 418/12, 249; 91/482; 137/625.11, 625.15

[56] References Cited 1 p: UNITED. STATES PATENTS 613,344 l1/1898 'White 418/249 530,961 12/1894 Nielsen 91/482 832,848 10/1906 Croston 418/249 X 3,233,047 12/1965 Toy.. 91/482 528,818 11/1894 Sparks 91/482 3,327,642 6/1967 Budzich.. 91/482 591,165 10/1897' Greenlu 418/12 888,806 5/1908 'l-lopkinsm, 418/12 Primary Examiner-Allan D. l-lerrmann Attorney-Hume, Clement, Hume & Lee

57 ABSTRACT This invention provides a valve system for directing charges of pressurized working fluid into the expandable chambers of a rotary engine, for operation against a pivoted powerarm associated with each chamber. The valve system includes a manifold for containing a supply of pressurized working fluid, and fluid intake ports associated with each expandable engine chamber. Fluid conduit means associated with each intake port communicate with the manifold, and valve means associated with each port are adapted to open or close the conduit means in a timed sequence. Cut-off means also are provided to stop the flow of working fluid to the 'engine chambers after the power arm associated with each port has moved through a selected portion of its power stroke. Switching means also may be included to selectively switch the rotary engine between simple and compound modes of operation.

7 Claims, 16 Drawing Figures PATENTED SEN 8 I973 SHEU 1 [1F 8 INVENTOR. JOHN N. HINCKLEY VAN T. STONEHOCKER.

D W. CLEMENT F. JAGER.

BY N HOW MEL PATENTED 3. 759 .640

SHEU 2 BF 3 3 D INVENTOR.

HOW Vl. CLEMENT MEL F. JAGER.

JOHN N. HINCKLEY VAN T. STONEHOCKER.

PAIENIEU EH 3.759.640

SHEEI n if 8 423 (H PC) 422 INVENTOR. JOHN M. HINCKLEY VAN T. STONEHOCKER.

HOWARD W. CLEMENT MELVIN F. JAGER.

I nsm 81912. 5 0

swears 0F 8 INVENTOR- JOHN N. HINCKLEY VAN T. STONEHOCKER HOWARD W. CLEMENT MELVIN F JAGER PATENTED 3 m a ma INVEN TOR.

' JOHN N. HINCKLEY. VAN T. STONEHOCKER.

uovmao w. CLEMENT MELVIN F. JAGER.

Omm

Omm owm own 1 no'rAnY ENGINE vALvs MEANS BACKGROUND AND GENERAL DESCRIPTION This invention relates generally to valves for prime movers and more specifically relates to valve systems for use with rotary engines of the swinging abutment type, such as described and claimed in the co-pending application of John N. I-Iinckley, filedon Sept. 24, 1969, under Ser. No. 860,684, now U.S. Pat. No. 3,684,413.

As well-known by those skilled in the art, one of the More particularly, there is a need to provide a valving system for rotary engines of the type described in said co-pending application of John N. Hinckley. The valve system for such engines must be capable of use in either simple or compound engine cycles, and further must be adaptable to permit adjustment of the admission of working fluid into the engine. The valve systems for such engines must also function to deliver charges of working fluid into selected fluid chambers of the engine at timed intervals which assures a smooth and continuous flow of power to the engine output shaft. The distribution of working fluid to the engine also must occur with maximum thermal efficiency and a minimum loss of energy due to friction and turbulent flow.

This invention meets the above-described needs and requirements of the art by providing valve systems for controlling the flow of pressurized working fluid to rotary engines. The valve systems in accordance with this invention can operate in combination with rotary engines having either a simple or a compound mode of operation. The valve systems also can operate to admit charges of working fluid into the operating chambers of rotary engines at variable cut-off rates, or for a fixed duration or degree of rotation of the rotor and shaft, such as at full admission.

Briefly, the valve system of the present invention includes a manifold for containing a supply of pressurized working fluid and fluid intake ports associated with each expandable chamber of the engine. Fluid conduit means place each intake port in communication with the manifold, and valve means associated with each port are adapted to open or close the conduit means in a timed sequence. Accordingly, charges of pressurized fluid will be sequentially admitted into the engine chambers. The valve system also includes cut-off means to stop the flow of fluid to the chambers after the associated arms move through a portion of their power strokes to control the duration of admission of fluid into the engine.

EXEMPLARY EMBODIMENTS Additional features and advantages of the present invention will become apparent from the following description of several preferred embodiments thereof, taken in conjunction with the accompanying drawings. In the drawings:

FIG. I is a partial cross-sectional end view of a simple external combustion engine incorporating a camoperated, adjustable poppet valve system in accordance with this invention;

FIG. 2 is a cross-sectional side view of the engine and valve system illustrated in FIG. I, as viewed along the line 2-2 in FIG. I;

FIG. 3A-D are removed partial sectional views of the adjustable valve system for selectively controlling the admission and cut-off of the working fluid in the engine illustrated in FIGS. ]l and 2; I

FIG. 4 is a partial cross-sectional end view of another embodiment of an external combustion engine incorporating an arm-actuatd adjustable slide valve system in accordance with this invention, with the engine adapted to be switchable between simple and compound modes of operation;

FIG. 5 is a cross-sectional side view of the switchable engine and valve system as viewed along the line 5-5 in FIG. d;

- FIG. 6 is aremoved end view of the fluid transfer plate incorporated in the valve assembly illustrated in FIGS. 4 and. 5;

FIG. 7 is an end view of the transfer plate shown in FIG. 6 schematically illustrating the relationship between the transfer plate and the arm-actuated valves of the present invention;

FIG. 8 is a cross-sectional side view of an engine incorporating a rotational sliding valve system in accordance with this invention;

FIG. 9 is a partial cross-sectionalend view of the engine and valve system embodiment illustrated in FIG. 8; t

FIG. 10 is a removed and enlarged cross-sectional view of the sliding valve plate and valve seat arrangement incorporated in the engine and valve system illustrated in FIGS. 8 and 9;

FIG. I1 is a cross-sectional side view of an engine incorporating a rotational sliding valve system which includes means to selectively vary the cut-off of the working fluid flowing into the engine;

FIG. 12 is a partial cross-sectional end view of the engine and valve system embodiment illustrated in FIG. 11; and

FIG. 13 is a removed and enlarged cross-sectional view of the sliding valve plate and cut-off plate arrangement incorporated in the engine and valve system illustrated in FIGS. 11 and I2.

EXEMPLARY EMBODIMENTS Cam-Operated Poppet Valve FIGS. 13 illustrate the adjustable cam-operated poppet valve system of the present invention incorporated within external combustion engine unit 100. The engine is a balanced unit which is very simple in construction and is particularly adapted for a simple mode of operation with a pressurized working fluid,

such as .carbon dioxide or superheated steam. The

structure and operation of the engine 100 are fully described in the co-pending l-Iinckley application Ser. No. 860,684 and will be referred to only briefly herein.

The engine unit 100 incorporates a double-lobe rotor 50 positioned within a generally cylindrical rotor housing 20 on a central drive shaft 30. A key 51 or the like connects the rotor 50 to the shaft 30 in a manner which permits the rotor to float laterally within the rotor housing 20. Six swinging abutment arms 40A-F are uniformly spaced within the interior of the rotor housing 2d, 60 apart, on pivot pins 41. The rotor 50 and arms 40 have approximately the same width as the rotor housing 20.

As seen in FIG. 2, one end of the housing 20 is closed by an exhaust housing 60, and the other end is closed by a valve housing 70. The housings 60 and 70 support the shaft 30 on main bearings 61 and 71 and also support the arm pivot pins 41. Machined face plates 62 and 72 seal the adjacent ends of the rotor housing 20. Suitable means, such as discontinuous labyrinth sealing grooves 42 and 52 can be provided on the side portions of the arms 40 and rotor 50, respectively, to seal the arms and rotor with respect to the face plates.

As illustrated in FIG. 1, the free end of each of the arms 40A-F includes a bevelled portion 43 adapted for engagement with the periphery of the rotor 50. A projection 46 on the inner surface of .each arm 40 defines the point closest to the associated pivot pin 41 at which the rotor 50 will engage with the arm. Further, a relief 47 in each arm allows clearance for the rotor. Each arm 40 also includes a valving portion 45A-F which extends beyond the arm pivot pins 41. 7

Further, the rotor housing 20 includes a plurality of elongate recesses 22 to receive each of the arms 40 when the arms are in their outermost position (e.g., arm 40A in FIG. 1). The rotor housing 20 also provides a plurality of arcuate recesses 25 for receiving the valve portions 45 of the arms 40 as the arms move inwardly toward the rotor 50. Sealing strips 44 in the housing 20 and the arms 40 prevent pressurized working fluid from becoming trapped in these recesses 25.

The engine 100 is also provided with means for admitting charges of pressurized working fluid into the rotor housing 20 in the proper sequence. In this regard, the valve housing 70 includes a plurality of uniformly spaced intake ports 23. As illustrated in FIG. 1, one of the intake ports 23 is positioned in each of the arm recesses 22 closely adjacent the free end of the associated arm 40. By this arrangement, a charge of working fluid can be admitted into the rotor housing 20 through these intake ports 23 and will flow inwardly against the rotor 50 and the associated arm 40, to thereby impart a torque force to the rotor. The arrangement of the intake ports 23 adjacent the free end of the arms 40 permits the charge of working fluid to initially contact the associated arm at a point of great leverage, so as to forcefully swing the arm inwardly against the rotor 50.

The rotor housing 20 also includes a plurality of exhaust ports 26 which are spaced uniformly about the housing to receive the working fluid from the six segments of the engine 100. As indicated in FIG. 1, an 'exhaust port 26 is positioned in each of the rotor recesses 25, directly adjacent the valving portions 45A-F on the arms 40. Hence, the arm valving portions 45 control the opening and closing of the associated exhaust ports 26. As illustrated by the position of the arms 40A and D, the ports 26 are closed when the arms arein their outermost positions. As similarly illustrated by the position of the arms 40C and F, the ports 26 are opened to the rotor housing 20 after the associated arm 40 has moved inwardly for a selected degree of rotation of the rotor 50, i.e., l to The exhaust ports 26 are thus positioned to assure that the operation of the charges of working fluid against the rotor and the adjacent arms 40 will overlap.

The exhaust ports 26A-F can be connected to a closed fluid system if the simple engine 100 is operated with steam as the working fluid. The spent working fluid would then be recycled to a steam generator for reheating and returning to the engine. On the other hand, if the working fluid is carbon dioxide or the like, the ports 26 can be connected to a suitable exhaust manifold system (not shown) and exhausted to the atmosphere.

The periphery of the double-lobe rotor is designed to permit each of the arms 40A-F to move through a complete cycle of operation twice for each rotor revolution. Furthermore, the rotor periphery is designed to allow the arms 40 to move inwardly and outwardly with substantially harmonic motion, so as to minimize inertia losses in the engine 100.

The rotor 50 defines a pair of symmetrical and diametrically opposed high dwell segments 54. As indicated by the arms 40A and D, the high dwell segments 54 are adapted to engage a pair of diametrically opposed arms, and to retain the arms in their outermost positions for a selected degree of rotor rotation. Symmetrical rotor fall segments 56 are adapted to be engaged by a pair of opposed swinging arms 40, such as arms 40C and 40F, as the anns are driven inwardly by the expanding working fluid. These segments 56 move the arms 40 inwardly with approximately simple harmonic motion, so that the working fluid operating against the arm 40 and the exposed portion of the rotor 50 transmits a substantial torque force to the shaft 30.

The double-lobe rotor 50 further includes a pair of symmetrical and diametrically opposed low dwell segments 57. The segments 57 followthe fall segments 56 on the rotor periphery and operate to slow the inward movement of the approaching pair of arms 40' (e.g., arms 40C and F), and maintain the engaged arms inward in preparation for a reversal of direction. The fall segments 56 engage with the pairs of arms, such as 40A and D, for between 55 and degrees of rotor rotation. Similarly, the low dwell segments 57 engage the pair of arms for between approximately 10 and 15 of rotor rotation. Since adjacent pairs of arms (e.g., 40A and 40B) are spaced 60 apart around the rotor housing 20, the fall segments 56 and dwell segments 57 provide a 10 to 15 overlap in the power strokes of adjacent arms. Thus, for 10 to 15 of rotor rotation, the charge of fluid associated with the four arms 40A, C, D and F are simultaneously transmitting a torque force to the rotor 50 and the shaft 30.

The periphery of the double-lobe rotor 50 additionally includes diametrically opposed and symmetrical rise segments 58. The rise segments 58 engage with the pairs of arms '40 after the dwell segments 57, with the rotor 50 rotating in a clockwise direction, and return the engaged pair of arms (e.g., arms 40B and E) to their outermost positions within the arm recesses 22. The rise segments 58 merge into the high dwell segments 54 so that the high dwell segments will continue to retain the engaged pair of arms 40 in such outward position. The rise segments 58 are positioned so that one pair of arms, such as arms 40C and F, does not begin a reversal of direction and move outward until the following pair of arms, such as arms 40A and D, have engaged with the fall segments 56 of the rotor and have opened the associated exhaust ports 26, such as the ports 26A and D. The rise segments 58 thereby also assure that the operation of charges against the rotor 50 and adjacent pairs of arms 40 are overlapped.

During the operationof the engine 100, each of the arms 40A-F will complete one cycle of operation, and

engage sequentially with a fall segment 56; a dwell segment 57; a rise segment 58; and a high dwell segment 54, as the rotor 50 rotatesthrough 180 degrees. The

double-lobe rotor 50 therefore produces two complete The engine 100 in accordance with this inventionis provided with a valving system 80 for admitting charges of pressurized working fluid through the intake ports 23 in the proper sequence, and for controlling the engine cut-off point so as to adjust the duration of the fluid admission. As illustrated in FIGS. 2 and 3, the valve system 80 is generally cylindrical in configuration and is secured to the outer side of the valve housing 70 by means of a mounting plate 81. The mounting plate 8 1 has a central aperture for receiving the shaft 30, and further includes a plurality of passages 82 alignedwith the intake ports 23 in the adjacent housing 70. Mounting pins 83 assure the proper alignment of the housing 70, the plate 81,- and the rotor housing 20.

The valving system 80 further includes an annular valve body 84 which is secured to the mounting plate 81 so as to surround the adjacent end of the shaft 30. An intake passage 85 adapts the body 84 for connection with an external source of pressurized working carries three valve push rods 95 which are uniformly spaced around the shaft 30 in a predetermined position with respect to the three poppet intake valves The rods 95 are adapted to slide radially in the member 94.

A circular hub 96 is positioned in axial alignment with the member 94 adjacent the end of the shaft 30. I

As seen in FIG. 2, the hub 96 frictionally engages within a groove 97 provided in the fixed cover plate 87, and thus can be rotated manually or automatically with respect to the member 94. The hub 96 further includes an inspection cap 99 and three uniformly spaced and radially extended keyways for receiving the radial keys 99 on the three valve control sectors 200. As shown in FIGS; SA-D, one sector 200 is positioned radially fluid. An annular intake manifold'86 is provided inthe with a pair of opposed arms 40. Working fluid which enters any one of the passages 88 hence will be directed simultaneously to the ports 23 of the'two opposed arms 40. Since the engine 100 includes six arms 40A-F, the valve body 84 includes three arcuate passages SSA-C, which are connected, respectively, between the ports 23 associated with the opposed arms 40A and 40D; the arms 40B and E; and the arms 40C and F.

I The valve assembly 80 also includes, a plurality of poppet-type intake valves 90 for selectively connecting the fluid passages 88A-C to the intake manifold 86. Since the engine 100 includes sixuniformly spaced arms 40 which operate in opposed pairs, it is sufficient to provide the assembly 80 with three uniformly spaced valves 90. Plugs 89 provide access to these valves 90 and seal the valves from the atmosphere. The plugs 89 also support compression springs 91 which bias the valves 90 inwardly toward a closed position against the valve body 84. As shown in FIGS. 3AD, the poppet valves 90 alsoinclude valve stems 92 arranged to extend inwardly into the interior of the valve body 84.

engagement with plate 81, by suitable bolts or the like, in a position surrounding the end of the shaft 30. The member 94 below each of the intake valves and adjacent each of the push rods 95. The circumferential positioning of the-sectors 2 with respect to the intake valves 90 and rods hence can be controlled, within a given range,

by manually or automatically rotating the hub 96.

. The valve mechanism 80 also includes a primary admission cam 201 and a cut-off control cam 202. These cams 201 and 202 are keyed to the adjacent end of the shaft 30,- and are aligned axially so that the primaryadmission cam 201 is sequentially engageable with the three push rods 95 and the cut-off control cam 202 is sequentially engageable with the three sectors200. As illustrated in FIGS. 3A-D, each of the cams 201 and 202 include opposed doublelobes 201A and 202A, re spectively. Thus, the cam lobes 201A and 202A will engage twice with each push rod 95 and each valve sector 200, respectively, for each complete rotation of the shaft 30. i

Means are also provided in the valve assembly 80 to respond to the radial movement of the push rods 95 and sectors 200 and thereby control the operation of the intake valves 90. In this regard, a rocker lever arm 205'is positioned on a fixed pin 206 adjacent each of the valves 90. One end of each lever arm 205 is en gaged with the upper end of the adjacent push rod 95, and the other end of each am 205 is joined to a cam lever 208 by means of a pivot pin 207. A spring-biased snubber rod 209 is mounted in the valve body 84 directly aligned with each of the levers 208 to prevent excess movement of the linkage formed by the arms 205 and 208 during the operation of the engine 100. The free ends of the levers 208 are positioned directly below the valve stem 92 of the adjacent intake valve 90. The levers 208 are also radially aligned with the adjacent sliding valve sectors 200.

To operate the valve system 80, in accordance with this invention, the hub 96 is rotated to station the three sectors 200 in the desired circumferential position with respect to the fixed push rods 95. Sincethe relationship between the cams 201 and 202 is fixed on the shaft 30, the relative positioning of the sectors 200 and rods 95 controls the time at which the cut-off control cam 202 disengages with the sectors 200 and lowers the sectors so the valve 90 can close. The adjustment of the hub 96 therefore adjusts the engine cutoff.

Referring in detail to FIGS. 3A-D, the operation of 'the engine 100 constantly rotates the shaft 30 and the the poppet valve 90 is retained in its closed position by the force of the compression spring 91.

However, as shown in FIG. 3C, further rotation of the shaft 30 engages the cam lobe 201A with the push rod 95, so that the lobe 201A drives the push rod 95 outwardly a predetermined distance. This motion of the rod 95 further causes the rocker arm 205 to rock about its fixed pivot pin 206 and thereby force the connecting pin 207 radially inward. The lever 208 is then rocked against the periphery of the raised sector 200 and its free end will thereby raise the valve stem 92 and open the valve 90. The valve 90 will remain in this open position as long as both the push rod 95 and the sector 200 are engaged with the respective lobes 201A and 202A on the cams 201 and 202.

The opening of the poppet valve 90 thereby brings one of the intake passages 88A-C into fluid communication with the intake manifold ring 86. A charge of pressurized working fluid, such as superheated steam or carbon dioxide, then can be directed against a pair of arms 40 through the diametrically opposed intake ports 23 which are connected to that intake passage 88.

As the shaft 30 continues to rotate, the same valving functions are repeated sequentially, at 120 intervals, by the valve system 80 for the remaining pairs of diametrically opposed arms 40.

As illustrated in FIG. 3D, the valve 90 is closed when the continued rotation of the shaft 30 moves the cam lobe 202A away from the sector 200. The sector 200 will then move inward to relieve the forces on the levers 205 and 208, and thereby cause the lever 208 to disengage the valve stem 92. The poppet valve 90 then will be returned to its closed position by the spring 91.

The valve system 80 also can be arranged to provide an advanced admission of working fluid through the poppet valves 90, to fill the passages 88A-C with working fluid before the associated arms begin their inward power strokes. To accomplish the advanced valving, the cam 201 is arranged on the shaft 30 with respect to the rotor 50 so that the cam lobe 201A engages with a push rod 95, and thereby begins the valve opening operation, before the associated pair of arms 40 begin their inward power strokes against the rotor. A suitable arrangement would permit the valving operation to precede the power strokes of the associated arms by approximately 5 of rotor rotation.

The cam 202 is designed and positioned to engage the sectors 200 for a selected degree of rotation of the shaft 30 and rotor 50. In the preferred embodiment, the cam 202 and sectors 200 cooperate so that the associated valves 90 are opened for a sufficient duration to assure the overlapping operation of adjacent pairs of arms. The cam 202 and sectors 200 also are designed and positioned to provide the engine 100 with a selected variable cut off between full admission and zero admission. For example, if superheated steam is the selected working fluid, it has been found that an optimum design for the valve assembly 80 would cut off the admission of steam to the expandable fluid chambers after about 25 percent of the inward power strokes of the associated arms.

' As explained in co-pending application Ser. No. 860,684, the operating cycle for the engine 100 is started by admitting charges of pressurized working fluid through the valve system 80 in the abovedescribed manner, so that separate fluid charges will be fed simultaneously through the ports 23 to a pair of opposed arms, such as the arms 40C and 40F. As indicated in FIG. 1, the fluid charge will operate against the associated arms 40C and F and the rotor 50, and drive the arms inwardly against the rotor fall segments 56. The pair of arms 40C and F will thereby transmit a double power stroke to the rotor 50.

As the rotor 50 continues to rotate, the valve system admits a second charge of working fluid into the intake ports 23 of the following pair of opposed arms, such as the arms 40A and D. The high dwell segments 54 of the rotor will subsequently release this second pair of arms 40A and D and permit the arms to engage with the fall segments 56 and transmit a double power stroke to the rotor. As described above, the fall segments 56 and dwell segments 57 are arranged so that the working fluid against the rotor and the adjacent pairs of arms, such as arms 40A and D and 40C and F will overlap for 10 to 15 of rotor rotation.

As further seen from FIG. 1, the inward stroke of the following pair of arms, such as 40A and D, will open the associated exhaust ports 26 (e. g., the ports 26A and D) after the four adjacent arms have completed the above-described overlapping operation. Then, the preceding pair of arms, such as arms 40C and F, will engage with the rise segments 58 and begin to move outward. The arms will then force the working fluid out of the engine through the exhaust ports 26 (e.g., 26A and D) which have been opened by the following pair of arms, such as arms 40A and D. This above-described cycle is repeated for each pair of arms every 60 of rotor rotation. Due to the double-lobe configuration of the rotor 50, the cycle is repeated twice by each pair of arms for each rotor revolution. Thus, the engine 100 will transmit twelve single power strokes, or six double power strokes, to the rotor 50 for each rotor revolution.

Arm-Actuated Slide Valve FIGS. 4-7 illustrate a single engine unit 300 which includes a double-lobe rotor 350 and six uniformly spaced swinging abutment arms 340A-F. The engine 300 is adapted to be switchable between simple and compound modes of operation, and includes a modified, arm-actuated slide valve assembly for controlling the admission of working fluid to the engine.

The double-lobe rotor 350 is positioned in a rotor housing 320 on a central drive shaft 330, and the six arms 340A-F are uniformly spaced within the housing 320 on pivot pins 341. The rotor 350 and the arms 340 are connected to the shaft 330 and the pins 341 with splines 351 or the like which permit the rotor and arms to float laterally within the housing 320. The arms 340 and the rotor 350 have approximately the same width as the rotor housing 320.

As shown in FIG. 5, the ends of the housing 320 are closed by an exhaust housing 360 and a valve housing 370. The housings 360 and 370 include main bearings 361 and 371, respectively, to support the shaft 330, and further include bearing means (not shown) to pivotally support the pivot pins 341 on which the arms 340A-F rotate during the operation of the engine 300. The pins 341 extend through the housing 370 and also support the sliding valve assemblies 450A-F, as illustrated in FIG. 7. Keys 341A on the shafts 341 assure that the aspin 341 in a fixed relationship.

Machined face plates 362 and 372 are defined by the interior faces of the housings 36d and 370, respectively, and seal the adjacent ends of the rotor housing 320. Furthermore, a plurality of discontinuous and unaligned labyrinth sealing grooves 352 and 342 are provided on the side portions of the rotor 350 and arms 340, respectively, to seal the rotor and arms with re spect to these end plates 362 and 372.

As seen in FIG. 4, the arms 340A-F include bevelled portions 343 at their free ends for engagement with the rotor 350. A projection 346 on each arm defines the point closest to the associated pivot pin 341 at which the rotor 350 will engage each arm, and a relief 347 allows clearance between each arm and the rotor during the operation of the engine. Each arm 340 further includes valving portions 345A-F extending beyond the pins 34l. The valving portions 345 are positioned adjacent to a plurality of exhaust ports 390A-F provided in the exhaust housing 360. Thus, the valving portions 345 will function to open and close the ports 390 as the associated arms 340 move inward and outward with respect to the rotor 350. A plurality of arcuate recesses 325 are provided in the rotor housing320 adjacent the arms 340 for receiving the valving portions 345 as the arms move inwardly toward the rotor 35d.

As further illustrated in FIG. 4, each of the arms 340A-F defines an integral wedge-shaped horn member 348. The horns 348 are adjacent the free end of the arms 340, and are spaced to allow the free arm ends to define substantial contact surfaces 344. The front edge 349 of each horn 348 is curved to be concentric with thepivot pin 341 and extends outwardly from the associated arm for a distance which exceeds the length of the inward arm stroke. Conforming wedge-shaped recesses 328 in the rotor housing 320 receive the horns 348 when the associated arm 340 is in its outermost position. An arcuate wall 329 in the recesses 324 is positioned to form a seal with the curved edge 349 on the arm 340 as the arm moves inwardly toward the rotor.

The recesses 328 and the rotor housing 320 thereby provide a plurality of sealed high pressure chambers HP,,. which expand in volume as the associated arm 340 moves inwardly toward the rotor 35th. A charge of high pressure working fluid, such as superheated steam, thus can be expanded in the chambers HP and will transmit a torque force to the rotor 350 by forcing the associated arm 340 inwardly against the rotor. lFluid in-' take ports 323 are provided in the valve housing 370 to place each of the high pressure chambers HP,,. in direct fluid communication with a source of high pressure fluid.

The engine unit 300 further includes a plurality of low pressure chambers LP spaced adjacent the contact surfaces 344 on the free end of the arms 34tlA-F. The chambers L? are adapted to receive a charge of working fluid, such as steam or the like, for operation against the associated arm contact surface 344 and the periphery of the rotor 350. Low pressure intake ports 324 in the valve housing 370 are in direct communication with each of the low pressure chambers LP By this arrangement, working fluid can be directed into the chambers LP through the intake ports 324 at the desired time during the operation of the engine 300.

The periphery of the rotor 350 defines symmetrical and diametrically opposed high dwell segments 354,

which will engage with the arms 340 to maintain the I arms outward for a predetermined degree of rotor rotation. The next portion of the rotor 3561? defines symmetrical and diametrically opposed fall segments 356 which will permit the arms 34% to be driven inwardly The rotor periphery further includes low dwell segments 357, which engage with the pair of arms for 10 to 15 of rotor rotation and prepare the arms for a re versal direction. Since the adjacent arms are spaced uniformly degrees apart in the rotor housing 32th, the fall segments 356 and dwell segments 357 cause the operation of the arms to overlap by 10 to 15 of rotor rotation. During that overlapping period, two pairs of opposedarms, such as arms 340A and D and 34M: and F, will simultaneously transmit their power strokes to the rotor 354).

The rotor 350 also includes a pair of symmetrical rise segments 358. The continued rotation of the rotor 350 will engage apair of arms, such as 343C and F, sequentially with the fall segments 356, the dwell segments 357, and the rise segments 358. The segments 358 return the arms to their outermost positions and are arranged on the rotor 35% so that the outward movement of a pair of arms does not begin until the preceding pair of arms has started its'inward movement along the fall segments 356. This arrangement assures that the preceding pair of arms, such as 343A and D, will open the associated exhaust ports 3% so that the outward arm movement will exhaust the spent working fluid from the engine 3041 through the open exhaust ports 39b.

The engine unit 3MB further includes a valving mechanism 46W for admitting charges of high pressure working fluid to the engine and for switching the engine betweensimple and compound modes of operation. As illustrated in FIG. 5, the control mechanism 4th) is positione'dadjacent the valve housing 370, and includes a transfer plate 42% and a valve body 446). The valve body 444) defines an annular pressure storage chest 4411 which is joined to an external source of working fluid, such as steam, by means of a suitable connection. The body 44@ also has six arcuate inlet ports 443 (FIG. 5) extending through to the adjacent transfer plate 424). The inlet ports 443 are uniformly spaced 60 degrees apart, and will function to direct fluid into the engine 300 from the pressure chest 441. Similarly, six pairs of valve ports 444 and 445 are provided in the valve body ill, adjacent the pivot pins 341 of the arms 34%, to re ceive the fluid flowing from the chest 441.

The transfer plate 424 includes passages and ports to control the flow of working fluid from the chest 441 through the ports 443, 444, and 445 and to the chambers HP andlLlP of the engine 304 in this regard, the transfer plate 420 includes six uniformly spaced L- shaped inlet passages 421 which extend in a direction concentric to the shaft 33th for a predetermined distance and then turn radially outward. As shown in FIGS. 5 and 6, the passages 42llthereby connect the inlet ports 443 to the adjacent valve port 444. The plate 420 further includes a series of six uniformly spaced L- shaped high pressure passages 422. One end of each passage 422 is in communication with the adjacent port 445 in the valve body 444), and the other end of each passage terminates in a port 423. As shown in W6. 5-,

the ports 423 are in axial alignment and fluid communication with the intake ports 323 in the valve housing 370, and thus lead directly into the associated high pressure chambers HP. Thus, when the gap between the ports 444 and 445 is bridged, the passages 421 and 422 are joined, and will place the inlet ports 443 in direct fluid communication with the high pressure chambers HP through the ports 423.

The transfer plate 420 also includes means for transferring high pressure working fluid directly from the pressure chest 441 to the low pressure chambers LP. The plate 420 hence has a series of six uniformly spaced low pressure passages 424. The passages 424 are generally L-shaped and have one end terminating in a transfer port 429 adjacent the passage 422 and the other end terminating in a port 425. The ports 425 extend through the plates 420 in axial alignment with the low pressure inlet ports 324 in the housing 370 (FIG. 4). The passages 424 thereby lead directly to the engine low pressure chambers LP. Hence, if the gap between the passages 422 and 424 in the plate 420 is bridged, the passages 421 and 424 will place the inlet ports 443 in direct fluid communication with the low pressure chambers LP. A transfer port 427 is provided in each passage 422 adjacent the port 429 to accomplish the connection between passages 422 and 424. Moreover, if the passages 421, 422, and 424 are joined at the same time, the high pressure working fluid in the chest 441 will simultaneously flow into both the low and high pressure chambers LP and HP associated with the same arms 340. Under such conditions, the engine 300 would operate as a simple engine.

The transfer plate 420 also includes six uniformly spaced transfer passages 426 to transfer the charges of working fluid from each high pressure chamber HP to the low pressure chamber LP associated with the next adjacent arm (e.g., the next arm to engage with the rotor 350), when the engine 300 is operating in a compound mode. One end of each transfer passage 426 includes a transfer port 428 spaced adjacent the port 427 in the passage 422. The other end of the passage 426 is positioned next to the low pressure passage 424 of the next adjacent arm 340. These ports 427 and 428 and passages 426 and 424 can be selectively connected, to join the high and low pressure chambers of adjacent arms (e.g., HP, and LP when the engine 300 is operated as a compound engine.

The valving mechanism 400 also provides a switchover assembly 430 for selectively switching the engine 300 between simple and compound modes of operation. The assembly 430 comprises a control ring 431 which is positioned within an annular aperture in the valve housing 370. The inner surface of the ring 431 has gear teeth which mesh with a gear 432. A control rod 433 connected to the gear 432 allows the circumferential positioning of the ring 431 to be shifted from outside of the valving mechanism 400. Six arcuate valving channels 434 are secured to the ring 431 by pins (not shown) so that adjustment of the ring 431 correspondingly shifts the channels 434. The channels 434 are held in sliding engagement with the transfer plate 420 by a wave spring 435. The channels 434 are positioned in radial alignment with the ports 427, 428 and 429, and can be shifted to selectively connect the ports 427 to either the adjacent transfer port 429 or the port 428. When connecting the ports 427 and 429, the channels 434 set the engine 300 for a simple mode of operation. Alternatively, when connecting the ports 427 and 428, the channels 434 set the engine for a compound mode of operation. The channels 434 are also constructed to block the port 428 when connecting with the port 429, and vice versa.

The duration of fluid admission in the illustrated engine 300 is controlled by a movable control ring 460. The ring 460 includes six uniformly spaced cut-off ports 461 which are arranged in axial alignment with the arcuate inlet ports 443 (FIG. 5). The inside surface of the control ring 460 has gear teeth which mesh with the gear 462 so that rotation of the shaft 463 on the gear 462 will rotate the ring 460. Hence, the admission duration for the working fluid directed into the engine 300 can be adjusted by rotating the shaft 463 and the control ring 460, and thereby changing the relative positioning of the cut-off ports 461 and the associated cut-off plate 451. As viewed in FIG. 7, a clockwise rotation of the control ring 460 would cause the plates 451 to close the ports 461 earlier in the arm movement cycle, and vice versa.

As illustrated in FIGS. 5 and 7, the valving mechanism 400 also includes six uniformly spaced sliding valve assemblies 450A-F. The valve assemblies 450 are secured for rotation with the pivot pins 341 of the six arms 340A-F by keys 341A, and slide with respect to the valve body 440 when the associated arm 340 swings with respect to the rotor 350.

One end of each valve assembly 450 defines a cut-off plate 451, which swings with the associated arm 340 and slides across the fluid inlet port 461 for the arm. Thus, as illustrated by the positions of the valve assemblies 4503 and E in FIG. 7, the cut-off plates 451 allow fluid to flow into the inlet ports 461 when the associated arms 340B and E are in their outermost positions. As further illustrated by the positions of the valve assemblies 450A and 450D, the cut-off plates 451 close the inlet ports 461 when the associated arms 340A and D are in their innermost positions. Each plate 451 thereby controls the cut off of the working fluid into the high pressure chamber HP associated with the connected arm 340.

The other end of each valve assembly 450 defines a pair of parallel bridge ports 452 and 453. The first bridge port 452 is adapted to connect the adjacent ports 444 and 445, when the associated valve assembly 451 and arm 340 are in their outermost positions (see valves 4508 and E and arms 340B and E). The bridge ports 452 thereby control the connection between the inlet passage 421 and high pressure passage 422 of the preceding arm 340 (e.g., the valve 450B associated with the arm 340B controls the passages 421 and 422 for the arm 340A). The second bridge ports 453 in the valves 450 similarly connect the low pressure passage 424 of the preceding arm 340 to the adjacent transfer passage 426 when the preceding arm and associated valve assembly 450 are in their outermost positions (see arms 3408 and E, and valves 4503 and E).

During the operation of the engine 300, the high pressure working fluid, such as superheated steam, is continuously fed into the steam chest 441 through a suitable connection. The working fluid is thereby maintained under pressure directly outside of the cut-off ports 461. To begin the engine operation, the control ring 460 is adjusted by the shaft 463 (FIG. 5) to set the desired steam admission duration by positioning the cut-off ports 461 in a selected position with respect to the arm-actuatedcut-off plates 451. The valve assemblies 450A-F control the admission of steam to the connected arms340A-F, respectively, and further control the admission into the pressure chambers of the next preceding arm (e.g., thevalve 450B controls admission into LP,, and HP,,, etc.). For instance, the fluid admission for the opposed arms 340A andD is controlled by the plates 451 on the connected valve assemblies 450A and D. The pressurized working fluid will enter the cut-off ports 461 only as long as the ports are exposed by the plates 451. However, fluid entering these ports 461 will not flow intothe associated pressure chambers LP, and D and EP and D until the following ,pair of arms 34013 and E are intheir outermost positions. Under those conditions, bridge ports 452 and 453 of the following valveassemblies 45GB and E connect the channel 421 to channel 422, and channel 424 to 'channel 426.

The mode of operation for the engine 300 is selected by adjusting the switchover valve assembly 430. For a simple mode of operation, the rod 433 is rotatedto position the six channels 434 to connect the ports 427 and 429 and to block the ports 428. With a simple mode of operation, charges of working fluid will flow intothe cut-off ports 461, which are opened by the opposed valve assemblies 450C and F, and into the associated ports 443 and channels 421. The charges then flow through the ports 444 and the bridge ports 452 on the valve assemblies 450A and D into the ports 445 and the high pressure passages 422. The charges continue to flow through the ports 423 and into the high pressure chambers HP and HP associated with the arms 340A and 3400, respectively.

The fluid flowing in the high pressure channels 422 simultaneously flows through the transfer ports 427 into the switchover valve channels 434 (FIG. and through the transfer ports 429. Hence, the steam charge also fills the low pressure passages 424 and will flow directly into the associated low pressure chambers LP and LP Since the switchover channels 434 block the ports 428 when the engine is set for simple operation, the fluid flowing from the passages 424 through the bridge ports 453 will not escape from the passages 426.

Thus, when adjusted for a simplemode of operation, the valve mechanism 400 directs working fluid simultaneously into the high and low pressure chambers of the pair of opposed arms 340C and 340E. The fluid will then operate simultaneously in both chambers against the exposed portions of the rotor 350 and the adjacent arms 340C and 340F and thereby impart adouble power stroke to the rotor 350.

This flow of fluid into the low and high pressure chambers HP HP LP and LP continues until the cut-off plates 451 on the valves 450C and F close the ports 461 (FIG. 7), and the arms 340C and F approach thelow dwell segments 357 on the rotor 350. The arms 340C and F then engage the rotor rise segments 356 and are driven outwardly, to thereby reduce the volume of the high'pressure chambers HP and HP Simultaneously, the next pair of arms 340A and D is forced inward by the charges of high pressure working fluid within the chambers HP,,, HP,,, LP, and LP,;. The charge reached those chambers by flowing into the cutoff ports 461 opened by the valve assemblies450A and D (FIG. 7). The charge then flowed from the passages 421 to the passages 422 through the bridge port 452 on .the valve assemblies 45013 and E. From the passage 422 the charge flows through ports 423 into the high pressure chambers HP, and HP and through the ports 427 and'429 and the switchover channels 434 into the passages 424 and the connected low pressure chambers As described above, the engine 360 is timed so that the power strokes of adjacent pairs of arms 340 overlap for 15 to of rotor rotation. Hence, the pairs of arms 340C and F are engaged with the dwell segments 357.

as the arms 340A and D are moving inwardly against the rotor fall segments 356. Thereafter, the arms 340C and F engage the rise segnents 358 and are driven outwardly, and the arms 340A and D have opened the associated exhaust ports 390A and D. The outward movement of arms 340C and F will reduce the volume of thehigh pressure chambers HP and and force the spent fluid charges from the passages 422 through the ports 427 and 429 and switchover channels 434 into ports 390A and D.

the low pressure passage 424 and the low pressure chambers LP and LP The spent charge will then exhaust from the engine 300 through the opened exhaust switchover channels 434 are shifted to connect the ports 4 27 and 428 and block the ports 429. By this arrangement, the high pressure working fluid will be blocked from flowing into the low pressure chambers LP through the ports 429 and passages 424. There will therefore be no simultaneous operation of the charge in the high and low pressure chambers associated with the same arm 340.

In the compound mode of operation, the charge of working fluid flows through the passages 421 and the bridge ports 452 of the valve assembly 450 connected to the preceding arms (e.g., 450A and D) into the passages 422 and connected high pressure chambers HP associated with a first pair of arms 341) (e.g., HP and Simultaneously, the fluid flows through the ports 427 and 42% and the switchover channels 434 and fills the transfer passages 426 associated with the preceding arms 340 (e.g., arms 340A and D). However, these passages 426 are initially blocked ofi' by the inward position of the valve assemblies 454) of the next pair of arms (e-.g., assemblies 4508 and E). The fluid charge will thus initially operate in the high pressure chambers HP (e.g., HP and p) of a first pair of arms 340. Then, the subsequent outward movement of the first pair of arms 340, induced by the rotor rise segments 358, will force the fluid charge into the connected transfer passages 426. At that point in the engine cycle, the rotor dwell segments 354 hold the next pair of arms 450 (e.g., 450B and E) outward so that the bridge ports 453 on the associated valve 450 (e.g., 4508 and E) communicate with the passage 426. The highpressure chambers, such as HP and p, are thereby coupled to the low pressure chambers, such as LP, and associated with the next pair of arms 340. The charge in the high pressure chambers is thereby transferred to the coupled low pressure chambers for a second or compounded operation against the next pair of arms 540. In the preferred arrangement, the rotor 350 and arms 340 are arranged so this transfer operation is completed while performing little or no work on the fluid charge.

The fluid charge is exhausted from the low pressure chambers LP through the engine exhaust ports 390 in the manner described above for the simple mode of operation. The cycle of operation for each pair of arms 340 is completed in the above-described manner twice for each revolution of the engine rotor 350.

Rotary Slide Valve FIGS. 8-13 illustrate two embodiments of a rotary slide valve system in accordance with the present invention. The rotary slide valve system illustrated in FIGS. 8-10 is incorporated within a simple external combustion engine unit, and is arranged to admit the working fluid into the engine at a fixed cut-off, such as at full admission. FIGS. 11-13, the rotary slide valve system is incorporated within a simple external combustion engine and is adapted to permit the cut-off of the working fluid, and thus the duration of admission of fluid into the engine, to be varied.

Referring to FIGS. 8 and 9, the simple engine 500 has the same basic design as the engine 100 illustrated in FIGS. 1 and 2. The engine 500 includes a double-lobed rotor 550 positioned within a rotor housing 520 on a central drive shaft 530. A key 551 connects the rotor 550 to the shaft 530 in a free floating manner. Six swinging abutment arms 540 are uniformly spaced on pivot pins 541 within the interior of the housing 520, 60 apart, as described with respect to the arms 40 in corporated in the engine unit 100.

As seen in FIG. 8, one end of the rotor housing 520 is closed by an exhaust plate 560 and the other end is closed by a valve plate 570. The plates 560 and 570 include main bearings 561 and 571, respectively, which support the central shaft 530. Bearings 562 and 572 also are provided at the ends of the arm pins 541 to support the arms in the plates 560 and 570. Since the valve system in accordance with this invention, does not rely on arm movement to control the admission valving, it is not necessary for the arm pins 541 to extend through the exhaust plate 560 or the valve plate 570. The need to seal the interior of the housing 520 at the location of the arm bearings 562 and 572 is thereby eliminated. Suitable means, such as discontinuous labyrinth sealing grooves or the like (not shown) is provided on the side portions of the arms 540 and rotor 550 to seal the arms and rotor with respect to the plates 560 and 570.

The basic construction and operation of the arms 540 and the rotor 550 in the engine 500 are the same as described with respect to the engine 100 illustrated in FIGS. 1 and 2. The charges of working fluid admitted into the housing 520 drive the arms 540 inwardly, in the proper sequence, against the periphery of the rotor 550. Each arm includes a valving portion (45A-F in FIG. I) which opens and closes associated exhaust ports (ports 26A-F in FIG. 1) to control the exhaustion of the spent working fluid from the chamber 520. Suitable channels, such as the exhaust channel 573 illustrated in phantom lines in FIG. 8, are provided in the exhaust plate 560 to direct the spent working fluid into an exhaust manifold in a well-known manner.

The engine 500 also includes means for admitting.

charges of pressurized working fluid into the housing 520 to drive the arms 540 inward in the proper sequence. The valve plate 570 is thus provided with six uniformly spaced intake ports 523, arranged adjacent the free ends of each of the arms 540, such as illustrated by the similar ports 23 in FIG. 1. Charges of working fluid admitted into the housing 520 through the ports 523 will be directed inwardly against the rotor 550 and the free end of the associated arm 540, and will operate to impart a torque force to the rotor and the shaft 530. As described above with respect to the engine 100, the exhaust channels 573 are positioned with respect to each arm 540 to assure that the operation of the charges of working fluid against the rotor and the adjacent arms 540 will overlap. As also described with respect to the rotor 50 in the engine 100, the periphery of the double lobe rotor 550 is designed to allow the overlapping of the inward power strokes for adjacent arms 540, and to move each arm through a complete cycle of operation twice for each rotor revolution.

The rotary slide valve system in accordance with this invention is generally indicated in FIGS. 8 and 9 by the reference numeral 600. The valve system 600 operates to admit charges of pressurized working fluid through the intake ports 523 in the proper sequence to operate the engine 500. In this embodiment, the system 600 is arranged to provide the engine 500 with full admission of the pressurized working fluid, that is, a charge of fluid will be directed to each arm 540 throughout the entire inward stroke of the arm.

As seen in'FIG. 9, the valve system 600 is generally cylindrical in configuration, and is secured to the outer side of the valve plate 570 by means of a mounting plate 601. Plate 601 has a central opening to receive the adjacent end of the drive shaft 530, and also includes six ports 602. One port 602 is aligned with each intake port 523 in the engine 500, so that working fluid can be admitted into the engine housing 520 through the aligned ports 523 and 602.

The valve system 600 also includes a cylindrical valve housing 603, which is secured to the mounting plate 601 by anchor bolts 604. A cover plate 605 closes the outer end of the housing from the atmosphere. A suitable shaft seal 606 seals the joint between the cover plate 605 and the drive shaft 530. Valve housing 603, like the mounting plate 601, is provided with six uniformly spaced intake ports 607 aligned with the ports 602 and 523 in the mounting plate and the valve plate 570, respectively. As illustrated in FIGS. 8 and 10, each of. the housing ports 607 includes a machined shear valve seat 608 which is biased outwardly by a spring 609 (rightward in FIG. 10). The seats 608 define a hollow shearing seal for the rotary slide valve in accordance with this invention, through which the working fluid can flow in a short, straight-line path from the housing 603 into the engine housing 520 by means of the aligned ports 607, 602, and 523. The same valve seat can be used in the engine 300 to maintain a seal between the valve ports 444 and 445 and the bridge ports 452 and 453, illustrated in FIG. 5.

The valve system 600 further includes a rotatable annular valve plate 610, adapted to rotate with the engine shaft 530. As shown in FIG. 8, the valve plate 610 is spaced closely adjacent the ports 607 provided in the housing 603, and is arranged to be in constant sliding contact with the shear valve seats 608. The bias of the seat springs 609 maintains the sliding contact as the plate 610 continuously rotates with the shaft 530 during the operation of the engine 500.

As shown in FIG; 9, the valve plate 610 includes concentric admission slots 612A and 6128 having a predetermined arcuate length. The slots 612A, B are arranged in axial alignment withthe valve seats 608 and the ports 607, 602, and 523. Thus, during a portion of the rotation of the plate 610 the slots 612A and B will be aligned with each of the seats 608, and will place the ports 607, 602, and 523 and the engine housing 520 in open fluid communication with the interior of the valve housing 603.

The size and number of slots 612A, B in the plate 610 is a function of the number of arms 540 and the design of the rotor 550 provided in the engine 500. in the illustrated embodiment, wherein the engine 500 includes six uniformly spaced arms 540 and a double-lobed rotor 550, the slots 612A and B in the valve plate 610 are identical and diametrically opposed. The arcuate length of each admission slot, along the plate angle alpha indicated in FIG. 9, and the width of the aligned ports 607, are selected to provide the desired admission and cut-off for the working fluid which will pass through the slots during the operation of the engine 500. Since the illustrated engine 500 is adapted for full admission, the length of the slots 612A and B, and the width of the ports 607, are selected to direct working fluid from the valve housing 603 into the rotor housing 520 during the complete inward power stroke for each arm 540. Since the arms 540 are uniformly spaced 60f apart, the slot length and port width combine to admit fluid into the rotor housing 520 through each port 607 for at least 60 of rotor rotation. In the illustrated embodiment, theslots 612A and B and the ports 607 are also designed to provide an overlap in the admission of the charges of working fluid into two adjacent expansion chambers. As described with respect to the engine 100, an overlap in arm movement in the range of of rotor rotation will assure smooth operation of the engine 500. Further, the admission slots 612A and B and ports 607 are selected to admit working fluid into each port 523 for about five degrees of rotor rotation in advance of inward movement of the associated arm 540. This advance admission brings the fluid in the ports 523, 602, and 607 up to the desired inlet pressure before arm movement begins. Hence, for full admission, the effective arcuate length of the admission slots 612A and B (the angle alpha) and the aligned ports 607 are preferably about 80 of rotor rotation.

The valve system 600 also includes driving means to rotate the sliding valve plate 610 in unison with the drive shaft 530 of the engine 500. In this regard, a timing hub 620 is keyed to the shaft 530, by a suitable key 621, to rotate with the shaft 530. A drive hub 630 is connected to the timing Mb 620 by a set of adjusting screws 631. As illustrated in FIG. 9, the screws 631 are positioned within slots 632 on the driving hub 630, so that the circumferential positioning of the driving hub 630 can be adjusted with respect to the timing hub 620.

The slots 632 thereby allow the timing of the admission of the working fluid into the engine 500 to be set within a selected range.

A plurality of uniformly spaced drive pins 633 rigidly v join the driving hub 630 to the valve plate 610. Thus,

the rotational force imparted to the timing hub 620 by the shaft 530 through the keys 621i is transmitted by the adjusting screws 631 to the driving hub 630, and is, in

turn, transmitted to thevalve plate 610 through the driving pins 633. A plurality of compression springs 634 are also spaced uniformly around the periphery of the, driving hub 630, to continuously bias the rotating valve plate 610 inwardly (leftward in FIG. 0) against the valve seats 608.

The cover plate 5 and the seal606 enclose the outer end of the valve housing 603. A shaft seal 635 is provided on the mounting plate 601 to seal the inner end of the valve housing 603 in the same manner. Thrust washers 636 are provided adjacent both ends of the timing hub 620m absorb any axial thrust created by the movement of the components of the system 600 during the operation of the engine 500. The housing 603 also includes an admission port 640 which can be connected to a suitable supply of working fluid and which operates to fill the housing 603 with working fluid during the operation of theengine.

To begin the operation of the engine 500, working fluid, such as superheated steam or carbon dioxide, is fed into the interior of the valve housing 603 through the admission port 640. As indicated in FIG. 9, the slots 612A and 6128 and ports 607 assure that at least a pair of diametrically opposed ports 523, 602, 607 will be exposed to the interior of the valve housing 603 at any time, regardless of where the rotation of the valve plate 610 was stopped during the previous operation of the engine 500. Thus, charges of pressurized working fluid will flow from housing 603 into the rotor housing 520 through a pair of the ports 523 and-act upon the rotor 550 and the associated pair of opposed arms 540. The pair of arms 540 will thereby be forced inwardly and transmita torque force to the rotor 550 and shaft 530. The aligned ports 607, 602, 523 define a straight-line path for the charges of working fluid, and thereby allow the charges to flow into the rotor housing 520 with minimum loss of energy due to friction and flow turbulence.

During the operation of the sliding valve system 600, the compression springs 634 constantly urge the rotating valve plate 610 axially inward (to the left in FIG. 8)

against the shear valve seats 608. The springs 609 simultaneously urge the seats 608 outward (to the right in FIG. 8) into engagement with the rotating plate 610. The springs 634 and 609 thus assure initial and continuous sealing contact between the sliding valve plate 610 and the valve seats 600. The pressure of the working fluid in the valve housing 603 also acts against the rotating plate 610 in a manner which assists this sealing action. As shown in FIG. 10, the valve seats 608 can include 0 rings to seal the seat to the housing.

As the pressurized working fluid continues to exert a torque force against the rotor 550, the rotor and the shaft 530 rotate in a clockwise direction as viewed in FIG. 1, or a counterclockwise direction as viewed in FIG. 0. The movement of the shaft 530 rotates the timing hub 620, the drive hub 630, and the valve plate 610 through the same angular movement, in the same direction. The admission slots 612A and 61213 are thereby successively rotated into axial alignment with diametrically opposed ports 607 602, 523 for a selected degree of rotor rotation. The valve plate 610 thus operates to control the successive admission of charges of working fluid into the engine 500. Since the engine 500 is adapted for full admission, the slots 612A and B admit working fluid into the ports 523 throughout the entire inward power'stroke of the associated arms 540. As described above, the total duration of the admission is preferably about 80 of rotor rotation, to allow for about advance admission, before any arm movement, and about of overlap in the operation of adjacent arms 540. The torque force transmitted to the rotor 550 and shaft 530 will thereby be continuous and substantially uniform.

FIGS. 11 through 13 illustrate a further embodiment of this invention wherein a modified sliding valve system 700 is adapted to permit manualadjustment of the cut-off for the admission of the working fluid into the engine 500A. The engine 500A is essentially the same as the engine 500, described above with respect to FIGS. 8 through 10, and hence like components have been given the same reference numerals in FIGS. 11 through 13. The modified sliding valve system 700 is secured to the engine 500A adjacent the valve plate 570 by means of a plurality of uniformly spaced anchor bolts 70].

Referring to FIGS. 11-13 in more detail, the slide valve system 700 includes a generally cylindrical valve body 703 which defines an interior fluid chamber or steam chest. A central aperture 702 in the body 703 receives the adjacent end of the engine shaft 530A. A series of positioning screws 704 assure that the valve body 703 is mounted on the valve plate 570 of the engine 500A in the proper position.

The valve body 703 includes a series of uniforml spaced channels or ports which allow working fluid to flow from the interior of the valve body into each intake port 523 of the engine 500A. In this embodiment the channels are formed by a plurality of ports 705A and 705B. The ports 705A and B are staggered around the valve body 703 in a uniformly spaced relationship. The inner ends of the ports 705A and B (the left end in FIG. 11) are aligned with the adjacent intake port 523. The ports 705A and B extend through the valve body 703 in divergent directions so that the outer ends of the channels 705A are spaced radially in the valve body from the alternate ports 705B. In the illustrated embodiment, the ports 705A are spaced radially outward with respect to the ports 705B. Each port 705A and B thus will permit working fluid to be admitted from the interior of the valve body 703 through the intake ports 523 and into the engine housing 520. The staggered and radially spaced arrangement for the ports 705A and B allows the duration of admission of the working fluid to be adjusted.

The valve system 700 also includes a rotatable sliding valve plate 710. The plate 710 is annular to provide a central opening for receiving the adjacent end of the shaft 530A. Furthermore, the plate 710 includes two sets of arcuate admission slots 712A and B and 714A and B which are positioned in diametrically opposed relationship. The plate 710 is arranged inside the valve body 703 coaxially with the shaft 530A so that the admission slots 712A and 714A are axially aligned with the outer ends of the ports 705A. Similarly, the admission slots 7128 and 714B aligned with the outer ends of the ports 7058. Thus, the working fluid can flow from the interior of the valve body 703 into the channels 705A through the admission slots 712A and 714A and into the channels 705B through the admission slots 7128 and 714B.

Means are provided in the valve system 700 to rotate the slotted valve plate 710 in unison with the shaft 530A. In this regard, a timing hub 720 is secured to one end of the shaft 530A by a suitable key 721. A driving hub 730 is joined for rotation with the timing hub 720 by means of adjusting screws 731. As seen in FIG. 12, the screws 731 are received by the driving hub 730 in slots 732 so that the timing of the valve system can be set by adjusting the relative positioning of the hubs 720 and 730. A series of uniformly spaced driving pins 733 join the driving hub 730 to the valve plate 710, so that the plate and hub will rotate in unison. The pins 733 are further arranged to allow the plate 710 to move axially with respect to hub 730 to facilitate sealing of the valve system 700 during the operation of the engine 500A.

The valve system 700 also includes a cut-off plate 740 to vary the cut-off duration for the charges of working fluid admitted into the engine 500A. The cutofi plate 740 is annular in configuration, and is positioned within the valve body 703 closely adjacent the sliding valve plate 710. The cut-ofi plate 740 includes a plurality of cut-off ports 741A and 741B which are positioned to selectively admit working fluid into the staggered ports 705A and B from the interior of the valve body 703. In the illustrated embodiment, atotal of six ports 741A and B are staggered and radially spaced in the cut-off plate 740. Three of the ports 741A are radially positioned for alignment with the outer admission slots 712A and 714A in the valve plate 710. The remaining three ports 741B are radially positioned for alignment with the inner admission slots 7123 and 714B. The ports 741A and B may be circular apertures as shown in FIG. 12, or can be arcuate slots, as desired.

A generally cylindrical pressure plate 750 maintains the cut-ofi' plate 740 in the proper position with respect to the valve plate 710. The pressure plate 750 includes a central hub portion 751 and a peripheral flange por tion 752. A plurality of drive pins 753 are provided in the flange portion 752 to join the pressure plate 750 to the cut-ofi' plate 740 so that the plates 740 and 750 can move axially with respect to each other, but will rotate in unison. A compression spring 754 is positioned around each pin to urge the cut-off plate 740 inwardly (to the left in FIG. 11) into continuous sliding contact with the rotating valve plate 710. A cover plate 760 supports the hub portion 751 of the pressure plate 750 within a central bearing 761. An inlet port 762 is provided in the cover plate 760 to allow the introduction of pressured working fluid into the valve housing 703.

In accordance with this invention, the valve system 700 includes a shifting apparatus which permits the cut-off rate of the engine to be varied by changing the,

position of the cut-off plate 740 with respect to ports 705 in the valve body 703. In this regard, a manual shifting lever 770 is fixed to the hub portion 751 of the pressure plate 750. A compression spring 771 biases the lever 770 upwardly toward a rachet type quadrant 772. A stop 773 on the lever 770 is engageable with the quadrant 772 to selectively retain the lever in a plurality of positions within the arcuate range of the quad rant. By this arrangement, the lever 770 can be rotated between two selected extremes to shift the position of the cut-off plate 740, and the cut-ofi ports 741A and B, rotationally with respect to the ports 705A and 705B in the valve housing 703.

As described with respect to the engine 500 shown in FIGS. 8-9, the geometry and positioning of the admission slots 712, 714, the valve body ports 705A, B, and the cut-off plate 740 determine the timing and duration or cut-off of the admission of working fluid into the engine 500A. In the preferred arrangement, the valve system 700 is designed to permit full admission (i.e., 100% cut off) of the working fluid into therotor housing 520 as a maximum duration of fluid admission and about 25 percent of the arm power stroke as a minimum admission duration (i.e., 25 percent out off). The full admission of working fluid facilitates start-up of the engine 500A, and the 25 percent cutoff provides a theoretical optimum utilizationof the energy in the working fluid, such as superheated steam.

To allow for full admission, the valve system 700 is dimensioned so that, in the illustrated embodiment, the effective length of the admission slots 7112, 714 (the angle alpha), in combination with the width of the ports 7 05, produces admission for about 80 of rotor rotation. As described with respect to the engine 500, such an arrangement provides about five degrees advanced admission, to till the various ports with pressurized working fluid, and about 15 of overlap in the operation of adjacent pairs of arms 540. To allow for a 25 percent cut off as a minimum duration of admission for the working fluid, the valve system 700 is arranged to permit the shifting of the cut-off plate 740 circumferentially with respect to the valve body 703 so that the effective length of the admission slots 712, 714, and ports 705 are diminished to produce admission for about 20-25 of rotor-rotation. A charge of working fluid will thereby flow. into the rotor housing 520 through the admission slots 712, 714 fora duration equal to the five degrees advanced rotation of the rotor, plus about 25 percent of the inward stroke of the associated arm 540.

durationot admission of the working fluid from the in? terior of the valve body 703 into the rotor housing 520, through the ports 705A, 7058, and 523. The location of the ports 705A and B control the admission of working fluid into the engine 500A under such conditions. Due to the selected arcuate length of the slots 7112 and 714, one of theset of slots 712A, 7MB or 712B, 7MB will be positioned in alignment with a pair of diametrically opposed ports 705A, B and 741A, B, regardless of the rotational positionof the valve plate 710. Hence, dead spots or dead-center conditions are eliminated from the engine 500A, and the engine will be selfstarting.

The valveplate 710 feeds a charge of working fluid into the rotor housing 520 for operation against two diametrlc'ally opposed arms M30, as described in detail with respect to the engine 500. The resulting movement of the rotor 550 and shaft 530A, in turn, drives the valve plate 710 in the same direction and at the same angular speed. Thev rotating plate 7110 sequentially exposes the aligned intake ports 705 and cut-off ports 741 to the-workingfluid within the valve housing 703, and thereby feeds charges of working fluid into the rotor housing 520, for operation against pairs of arms 540 at timed intervals. When adjusted for full admission, the plate 710 admits a charge of working fluid into each of the ports 705A and B for a period of approximately of rotor rotation in advance of arm.

movement; an additional rotor rotation of approximately 60 degrees to cause inward movement of the associated arms 5; and a final rotor rotation of approximately to assure overlapping operation of adjacent through the inlet ports 523 for operation against a pair of diametrically opposed arms 540. Since the arcuate lengths of the slots 712A, B and 714A, B are equal, the duration of the admission through the slots will be likewise equal.

To decrease the duration of admission of the working fluid into the rotor housing 520, the cut-off plate 740 of the valve system 700 is rotated by the lever 770 in a direction opposite to the direction of rotation of the "valve plate 710. As viewed in FIG. 12, the shaft 530A and the valve plate 710 rotate in a counterclockwise direction during the operation of the engine 500A. Accordingly, the cut-ofl rate of the engine is adjusted by rotating the cut-ofi plate 740 in a clockwise direction. As seen in FIG. 12, this adjustment positions the cut-off ports 741A andMiB in advance of the inlet ports 705A and.705B in the stationary valve housing 703.

Hence, as the valve plate 710 rotatescounterclockwise, the admission slots 7112 and 7114 become aligned with the cut-off ports 741A and 741B before reaching the inlet ports 705A and B. Since the circumferential positions of the inlet ports 705A and B are fixed, the adjustment of the cut-off plate 740 in a clockwise direction does not aflect the timing for the alignment of the admission slots 712 and 7M with'the ports 705A and B. Thus, the valve system 700 operates to begin the admission of charges of working fluid into the rotor housing 520 at the same initial time in the engine operating cycle under all cut-off adjustments.

The arrangement of the cut-off ports 7411A and Mil; in advance of the fixed ports 705A and B will cause the admission slots 712 and 7 M to become aligned with the cut-off ports 741 before reaching the ports 705. In the same regard, the rotating admission slots7i2, 714- will remain aligned with the fixed ports 705A, B after rotation beyond the associated cut-off port 7411A, B.

As illustrated in FIG. 12, the fluid will flow into the rotor housing 520 only as long as the associated cut-oft" port 7011A, B is aligned withone of the admission slots 712A, B or 714A, B, and will be cut off when the admission slots rotate beyond the'cut-off ports 741A, B.

Thus, the clockwise rotation of the cutoff plate 740 advances the cut-off of the working fluid into the admission slots 7T2 and 7M, so that the fluid operates I against a pair of arms 500 for a duration of rotor rota-

Claims (7)

1. In a rotary engine having a rotor joined to a power output shaft, a plurality of pivoted power arms spaced uniformly around the rotor and sequentially movable in a generally radial direction against the rotor through an inward power stroke from an outermost to an innermost position to transmit a torque force to the rotor and shaft, and expandable fluid chamber associated with the radially outward side of each arm, the improvement comprising a rotary slide valve system for sequentially directing charges of working fluid into said chambers to drive the arms inwardly through their power strokes, said valve system comprising: a manifold for a supply of pressurized working fluid; fluid intake port means for each chamber in communication with said manifold; a rotatable valve plate joined for rotation in timed relationship with said rotor and positioned adjacent said intake port means to block fluid communication between said intake port means and said manifold, said valve plate including admission aperture means sequentially alignable with said intake port means as said plate rotates with said rotor and shaft, to connect said intake port means in fluid communication with said manifold, said admission aperture means in said plate having a selected arcuate length along an arc substantially concentric with said rotor to direct charges of working fluid from said manifold sequentially into said chambers through said intake port means for a selected degree of rotation of said rotor so that said charges sequentially drive said arms through said inward power strokes.

2. A vAlve system in accordance with claim 1 wherein said arcuate length of said admission aperture means is selected to connect adjacent intake port means simultaneously in fluid communication with said manifold for a selected degree of rotation of said plate, to overlap the sequential admission of charges of working fluid into the chambers of adjacent arms and thereby overlap the inward power strokes of adjacent arms for a selected degree of rotor rotation.

3. A valve system in accordance with claim 1 including adjustable fluid cut-off means in fluid communication with said manifold and shiftable from an opened position, permitting fluid to flow from said manifold into said admission aperture means, and a closed position cutting off the flow of fluid from said manifold into said intake port means for a selected degree of rotation of said rotor.

4. A valve system in accordance with claim 1 including valve seats associated with each of said intake ports and slideably engaged with said rotatable valve plate to maintain a substantially fluid-tight seal between said plate and said intake ports during the operation of said engine.

5. In a rotary engine having a rotor joined to a power output shaft, a plurality of pivoted power arms spaced uniformly around the rotor and sequentially movable against the rotor through an inward power stroke from an outermost to an innermost position to transmit a torque force to the rotor and shaft, and an expandable fluid chamber associated with each arm, the improvement comprising a rotary slide valve system for sequentially directing charges of working fluid into said chambers to drive the arms through their power strokes, said valve system comprising: a manifold for a supply of pressurized working fluid; fluid intake ports for each chamber in communication with said manifold; a rotatable valve plate joined for rotation in timed relationship with said rotor and shaft and positioned adjacent said intake ports to block fluid communication between said intake ports and manifold, said valve plate including admission ports alignable with each intake port as said plate rotates to thereby connect said intake ports with said manifold, with said admission ports being arranged on said plate in radially staggered relationship with respect to said shaft so that adjacent admission ports communicate with said manifold at different radial locations on said plate; and an adjustable cut-off plate positioned adjacent said valve plate and operative to adjust the flow of fluid from said manifold into said intake ports by shifting circumferentially with respect to said intake ports, said cut-off plate including a cut-off port positioned for axial alignment with each admission port on said rotating valve plate and radially staggered around said cut-off plate; whereby said rotating valve plate directs charges of working fluid from said manifold into said chambers sequentially through said admission and intake ports for a selected degree of rotation of said rotor and shaft, to drive the arms through their inward power strokes, and said cut-off plate is shiftable with respect to said intake ports to adjust the duration of admission of fluid charges from said manifold into said engine chambers.

6. In a rotary engine having a symmetrical double-lobed rotor joined to a power output shaft, a plurality of pivoted power arms spaced uniformly around the rotor and movable against the rotor through an inward power stroke to transmit a torque force to the rotor and shaft, and an expandable fluid chamber associated with each arm, a valve system for directing charges of working fluid sequentially into said engine chambers so that the power strokes of pairs of opposed arms coincide, said valve system comprising: a manifold for receiving a supply of pressurized working fluid; a plurality of intake ports uniformly spaced around said manifold at a selected radial position with respect to said shaft and extending into fluid communicAtion with each engine chamber; a rotatable valve plate joined for rotation in timed relationship with said rotor and shaft and positioned adjacent said intake ports to block fluid communication between said intake ports and said manifold, said valve plate including at least a pair of concentric admission apertures having substantially the same arcuate length arranged in diametrically opposed relationship and positioned for alignment with said intake ports to place said intake ports in fluid communication with said manifold and thereby admit working fluid simultaneously into the engine chambers of an opposed pair of arms as said valve plate rotates to align said apertures with opposed intake ports.

7. In a rotary engine having a symmetrical double-lobed rotor joined to a power output shaft, a plurality of pivoted power arms spaced uniformly around the rotor and movable against the rotor through an inward power stroke to transmit a torque force to the rotor and shaft, and an expandable fluid chamber associated with each arm, a valve system for directing charges of working fluid sequentially into said engine chambers so that the power strokes of pairs of opposed arms coincide, said valve system comprising: a manifold for receiving a supply of pressurized working fluid; a plurality of intake ports uniformly spaced around said manifold and extending into fluid communication with each engine chamber, with the portion of said intake ports communicating with the manifold being arranged in a staggered relationship so that adjacent sets of intake ports communicate with said manifold at different radial positions with respect to said output shaft, a rotatable valve plate joined for rotation in timed relationship with said rotor and shaft and positioned adjacent said intake ports to block fluid communication between said intake ports and said manifold, said plate including a pair of concentric and diametrically opposed admission slots in axial alignment with each of said staggered sets of intake ports, said admission slots having substantially the same arcuate length and being operative to place diametrically opposed intake ports in fluid communication with said manifold and thereby admit working fluid charges simultaneously into the engine chambers of a pair of opposed arms as said valve plate rotates to align said apertures with said opposed intake ports; and an adjustable cut-off plate positioned adjacent said valve plate and operative to cut off the flow of fluid from said manifold into said intake ports, said cut-off plate including a plurality of cut-off ports radially staggered around said cut-off plate and positioned for axial alignment with said admission slots on said rotating valve plate, said cut-off plate further being shiftable circumferentially with respect to said intake ports to adjust the duration of admission of fluid charges from said manifold into said engine chambers through said intake ports and admission slots; whereby said rotating valve plate directs charges of working fluid from said manifold simultaneously into the chambers associated with a pair of opposed arms and said cut-off plate adjust the duration of admission of said fluid charges for a selected degree of rotation of said rotor and shaft.

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