US802768A

US802768A - Rotary engine.

Info

Publication number: US802768A
Application number: US24534105A
Authority: US
Inventors: William N Mears
Original assignee: Individual
Current assignee: Individual
Priority date: 1905-02-13
Filing date: 1905-02-13
Publication date: 1905-10-24
Anticipated expiration: 1922-10-24

Description

PATENTED OCT. 24, 1905.

W. N. MEARS.

ROTARY ENGINE.

APPLICATION FILED I'EB.13 1905.

5 SHEETS-SHEET 1.

No. 802,768; PATENTED 001 24, 1905;

w. N. MEARS.

ROTARY ENGINE.

APPLIOATION FILED 212.13. 190s.

5 SHEETS-SHEET 3.

Fig.5.

No. 802,768. PATENTED OUT. 24, 1905. w. N. MBARS.

ROTARY ENGINE. APPLICATION FILED FEB. 13, 1905.

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PATENTED 001. 24, 1905.

W. N. MEARS. ROTARY ENGINE.

APPLICATION FILED FEB. 13, 1905.

5 SHBETS-SHEET 5.

Inveniar: mlllllm NMears;

Witnesses:

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PATENT GFFIGE.

WILLIAM N. MEARS, OF BROOKLINE, MASSACHUSETTS.

ROTARY ENGINE.

Specification of Letters Patent.

"Patented Oct. 24;, 1905.

Application filed February 13, 1905- Serial NU. 245,341.

To all whom it may concern.-

Be it known that 1, WILLIAM N. MnARs, a citizen of the United States of America, and a resident of Brookline, in the county of Norfolk and State of Massachusetts, have invented certain new and useful Improvements in Rotary Engines, of which the following is a specification.

This invention relates to rotary engines, and has for its object the production of an engine of this class which is capable of developing the maximum of power with the consumption of a minimum quantity of steam, thereby in creasing the economy of the engine over those of a similar type heretofore known. In order to accomplish this object, the engine is pro- 1 vided with means whereby the steam may be used expansively after the admission has been cut off and with various instrumentalities by which peripheral resistance is reduced to a minimum.

The invention further consists in certain novel features of construction and arrange ment of parts, which will be readily understood by reference to the description of the drawings and to the claims to be hereinafter given. It is an improvement upon the invention shown and described in another application of mine filed October 13, 1904, numbered 228,312.

Of the drawings, Figure 1 represents an elevation of an engine embodying the features of this invention. Fig. 2 represents a longitudinal vertical section of the same, the cutting-plane being taken on line 2 2 on Fig. 1. Fig. 3 represents a vertical transverse section, the cutting-plane being on line 3 3 on Fig. 2. Fig. 4 represents a horizontal section on line 4 4 on Fig. 3. Figs. 5 and 6 represent sections through a portion of the piston-carrying cylinder and the casing, showing passages for the admission of steam to rotate the pistons and for exhausting the same. Fig. 7 repre sents a sectional elevation of the admissionvalve and means for operating the same. Figs. 8 and 9 represent inverted plans of the same, showing the coacting valves in different relations to each other. Fig. 10 represents a perspective view of the rotary valve. Fig. 11 represents a perspective view of the slidevalve coacting therewith and its driving-gear. Fig. 12 represents a view of the inner wall of the piston-chamber adjacent the admissionports, and Fig. 13 represents a transverse section of a modified form of engine.

Similar characters designate like parts throughout the several figures of the drawings.

in the drawings, 10 represents a casing in hubs 11, of which is mounted a revoluble shaft 12. Keyed to the shaft 12, as at 13, and Within recesses 14 in the casing 10 are end plates or disks 15. Between these end plates 15 is interposed a piston-carrying cylinder 16, said plates and cylinder being connected together by means of bolts 17. The end plates 15 are each provided with a plurality of sockets 18, adapted to receive the trunnions 19 on the rotatable pistons 20. These pistons 20 are segments of a cylinder and are mounted in grooves 21, extending longitudinally of the piston carrying cylinder from end to end between said end plates 15. The inner wall of the casing 10 forms with the pistoncarrying cylinder 16 a crescent-shaped chamber 22, to which working fluid is communicated. through the ports 23 and from which said working fluid is exhausted through the main exhaust 24 and the auxiliary exhaust 25. Between the admission-ports 23 and the auxiliary exhaust 25 the inner walls of the easing are formed concentric with the periphery of the cylinder 16 and furnish a bearing-surface therefor adapted to prevent the leakage of the working fluid from one port to the other. The inner wall of the casing is of a pcculiar shape, being so formed as to secure the best possible results from the working fluid utilized. From the admission-ports to the main exhaust the chamber 22, or the space between the periphery of the piston-carrying cylinder and the inner walls of said casing, never decreases in area, but for the greater part of the way gradually increases. At the outset when the working fluid first commences to act upon a piston 20 it is desirable that as great a surface of said piston be presented to the action of the working fluid as is possible, and to this end from the admission-ports to a point a the inner walls of said casing are made eccentric to the axis of the piston-carrying cylinder 16 and of such a shape as to form an enlarged chamber 26 at this point, which will permit the piston 20 moving a greater distance outward from the periphery of the cylinder 16 to present a greater surface thereof to be acted upon by the workingfluid admitted through the ports 23. From a to Z) the inner wall of said casing is made concentric to the axis of the cylinder 16, but respace 27 between the periphery of the cylinder and the inner wall of the casing through which the pistons move, the area of which is not changed until the point 6 is reached, from which point the inner walls of the casing are again made eccentric to the cylinder 16, the area of the space from that point to the point of the main exhaust gradually increasing. The pistons are mounted in the longitudinal grooves in the piston-carrying cylinder 16 and are so located that the distance between adjacent pistons is considerably less than the distance between the admission-ports and the .main exhaust-port, so that the working fluid admitted through the admission-ports 23 will be confined in pockets formed by said pistons, the inner wall of the casing, and the periphery of the cylinder 16, the working fluid being permitted to work expansively in said pockets to assist in the rotation of said cylinder and shaft. The enlargement 26 of said chamber 22 permits the working fluid to secure a better initial action upon said pistons than would be secured if this enlarged chamber was omitted, while the concentric portion 27 of said chamber permits the cylinder to secure the full benefit of said initial action without permitting the working fluid to work expansively, this result being due to the fact that when passing through this portion the area of the pistons 20, projected beyond the periphery of the cylinder 16, are the same, and the pressure of the imprisoned steam or working fluid contained in the pockets between said pistons will be utilized. As soon, however, as the point 5 has been reached the area of the projected portion of the piston in advance is greater than that in the rear, and the working fluid is permitted to work expansively thereon to continue the movement of said cylinder 16 left-handedly until the point of exhaust 24 is reached, when the Working fluid will exhaust through this passage into the exhaust-chamber 28.

It will be seen from the foregoing that when the live steam or Working fluid is admitted through the ports 23 it will immediately act upon that portion of the pistons projected beyond the periphery of the cylinder and move the cylinder left-handedly about its axis, and as soon as a piston has passed beyond the ports 23 the steam admitted ahead of said piston will be confined between it and the preceding piston, and this steam will be permitted to act on the preceding piston to continue the movement of said cylinder. This will continue until the rear piston reaches the point a, when the pressure of the imprisoned steam upon the pistons Will be equalized, and the steam will not as a consequence act expansively on said pistons until the preceding piston passes the point 7), when the Working fluid will again be permitted to act expansively upon the leading piston, said expansion continuing until the leading piston uncovers the exhaust-port 24, when the imprisoned steam or working fluid will be permitted to escape. Should any of the steam or working fluid remain in the chamber 22 after the piston 20 has passed the port 24, it will be permitted to escape through the auxiliary exhaust-port 25, this port communicating with a passage 30, entering the valvechest 31, in which is revolubly mounted a three-way valve 32. The valve 32 is provided with Y-shaped inlet-passages extending through the same and exhaust-passages parallel with its axis. With the valve in the position shown in Fig. 3 steam or other working fluid is led from the inlet 33 through the passages 34 35 into a supply-reservoir 36. In one chamber 37 of this reservoir is mounted a cylindrical rotary valve 38, open at either end, as at 39, so that the steam or other working fluid contained within the reservoir may freely pass therethrough. The valve 38 is also provided with ports 40, which in its revolution communicate with ports 41 in a division-wall between the main reservoir 36 and the rotary valve-chamber 37. Intermediate said rotary valve 38 and said admission-ports 23 is located a slide-valve 42, provided with a plurality of ports 43, which are adapted to cooperate with the ports in the rotary valve 38 to permit the steam confined in the reservoir 36 37 to pass to and through the ports 23 into the chamber 22. When the valve 32 is in the position just described, the longitudinal peripheral passage 44 communicates with the auxiliary exhaust 30 and permits the steam or other working fluid to pass therefrom through said longitudinal peripheral passage 44 to the annular passage 45 and thence through a port 46 into the exhaust-chamber 28, from which the steam or working fluid is permitted to escape through the outlet-pipe 49. When it is desirable to reverse the enginetemporaril y, the valve 32 may be moved into such position that the passage 35 will communicate with the passage 30 and the passage 47 will communicate with the inlet 33, while the longitudinal peripheral passage 48 will communicate with the reservoir 36, thus allowing the ports 23 to become an exhaust and the auxiliary exhaust-passage to become an admission port. The normalcondition, however, of running is left-handedly, the ports 23 being the admission-ports and the exhaust being through the

ports

24 and 25, this particular engine shown and described being adapted only for reversing temporarily. The rotary valve 38 has secured thereto a stem 50, mounted in suitable bearings 51 in the easing 10, and said stem has secured thereto a sprocket-wheel 52, connected, by means of a sprocket-chain 53, to a sprocket-wheel 54 on the main shaft 12, so that the rotary valve 38 is rotated in unison with the cylinder 16.

The slide-valve 42 is provided on its under surface with a rack 55, with which a pinion 56 meshes, said pinion being secured to a shaft 57, mounted in suitable bearings and having splined to its opposite end a pinion 58, which is movable longitudinally of said shaft to engage or disengage a rack member 59, secured to a governor 60, said governor being driven by spiral gears 61 62, the latter being secured to a shaft 63, the outer end of which is provided with a pulley 64:, driven through the medium of a belt 65 from a pulley 66 on the shaft 12. The shaft 57 is also provided with a hand-wheel 67, by which the slidevalve 12 may be operated manually when the pinion 55 is removed from engagement with the governor-rack 59.

The slide-valve 12 is provided with a plurality of ports 68, which cooperate with the ports in the rotary valve 38 to permit steam or other working fluid to pass from the reservoir 36 37 to the ports 23 and into the chamber 22. These ports are so arranged and constructed that a movement of the slide-valve 42 beneath the rotary valve 38 will regulate the amount of steam passing through these ports when the ports 10 in the revolution of the valve 38 coincide with the ports 68 in the slide-valve. Each of these ports 68 in said slide-valve 4:2 is adapted to cooperate with a plurality of ports 40 in the rotary valve 38 as said valve revolves about its axis, and these ports are so arranged that a full supply of steam will pass through said ports at their opening and gradually be shut oif in any wellknown manner. The valve 38 is also provided with a plurality of auxiliary ports 69, which will also cooperate with the ports 68 when the slide-valve 42 has been moved into the position shown in Fig. 9, so that a continuous admission of steam or other working fluid from the chamber 37 will be permitted to pass through said

ports

40 and 69 into the chamber 22, as is sometimes desired.

When the cylinder 16 revolves about its axis, the pistons 20 will lie flush with the periphery of said cylinder as they pass along the contacting concentric portion 70 between the exhaust-passage 25 and the inlet-passage 23. When a piston has passed beyond the admission-ports, the centrifugal action will cause the rear portion of said piston to be projected beyond the periphery of said-cylinder and furnish an abutmentupon which the live steam admitted through the ports 23 may act to cause the revolution of said piston-carrying cylinder. In order to assist this centrifugal action, each piston is provided with a weight 71, which in the revolution of the cylinder 16 will tend to move outwardly around the axis of said piston 20 to keep the outer and rear corners of thepistons in contact with the inner wall of said casing. The pistons 20 are arranged so that between the periphery thereof and the wall of the groove in which they are mounted there is a small space. In a groove extending longitudinally of the cylinder 16 is an antifriction-roller 72, which bears upon the periphery of said piston 20 from end to end. The peripheries of the pistons 20 near their outerends are also provided with antifriction members 73, extending from end to end thereof, which bear against the inner wall of the grooves 21, these antifriction members 73 forming a confined pocket when the pistons are in their normal position with their outer surface flush with the periphery of the cylinder 16. A passage 74 in the end plates or disks 15 communicates with a recess 75 in the periphery of the cylinder 16. As the cylinder 16 revolves this recess 75 will communicate with a passage 76 in the casing 10. The other end of said passage 76 communicates with a chamber 22, thereby permitting live steam to pass from the chamber through the passage 76 into the recess 75 and through the passage 74 into the confined pocket between the abutments or antifriction members 72 73, this steam thereby acting upon the members 73 to cause the piston 20 to be rotated and a portion thereof projected beyond the periphery of the cylinder 16 against the inner wall of the casing 10. Intermediate said antifriction member 73 and extending from end to end of said piston is a shallow groove 77, furnishing a wall or abutment for the steam to act upon. In the bridges 78 between the ports 23 are recesses 79, the rear wall of which furnishes a square shoulder or abutment 80 for the reaction of the steam admitted through said ports and acting upon the pistons passing by the same. To further assist in the rotation of said pistons in order to project a portion thereof outward into contact with the inner walls of the casing, said pistons are provided with a longitudinal rib 81, the sides of which form shoulders or abutments upon which the steam may act to move said pistons about their axes in an obvious manner. When the pistons have been projected to their fullest extent with the antifriction members 73 beyond the periphery of the cylinder 16, the steam in the chamber 22 will pass into the space between the inner wall of the groove 21 and the periphery of the piston 20, and when said pistons'reach the other end of the crescent-shaped space or chamber 22 and the inner wall of said casing commences to act upon said pistons to return them to their normal position flush with the periphery of the cylinder 16 provision must be made so that said steam in said space will not act as a cushion to prevent the return. To provide for this, a recess 82 is cut in the inner wall of the casing 10 in a position where a port 83 from the passage 74: communicates with it to permit the steam or other working fluid in the confined pocket between the abutments 72 73 being forced outwardly through this recess 82 into a passage 84: and through it into the exhaust-charm ber 28.

By the construction shown and described herein the pistons are mounted on trunnions where the frictional surface is reduced to a minimum, while the outer periphery of said pistons is provided with antifriction members which cooperate with other antifriction members in the cylinder, which greatly reduces the friction on the periphery thereof. At the same time this construction permits of steam being admitted between these antifriction members or abutments to cause the pistons to be rotated to project a portion thereof outwardly beyond the periphery of the cylinder 16.

As has been described, the piston 20 is also provided with abutments on which the steam may act to assist in this rotation about their axes, while at the same time other meansnamely, a removable weightis provided to further assist in this operation. This weight 71 may be removed and replaced by other members of greater or less weight, as may be desired.

By the provision of a hollow rotary valve to which steam is admitted from either end and in which the pressure is perfectly balanced the friction thereonis reduced to a minimum and at the same time it is conveniently operated by means of the revoluble shaft 12 in unison with the cylinder 16, the ports therein being arranged so as to permit steam or other working fluid at the proper time to cooperate with the pistons passing beneath the admissionport 23, one of which is longer than the other, as indicated at in Fig. 3.

The governor regulates the speed of the engine by operating the slide-valve 42, and disconnecting mechanism is provided between the governor and said slide-valve, so that the latter may be operated by hand independently of the governor when desired.

The modified form of engine shown in Fig. 13 is of a non-reversible type, and as a consequence the pistons 20 are constructed and arranged to project but one surface beyond the periphery of the cylinder 16.

It is believed that from the foregoing the operation of the engine will be thoroughly understood without further description.

Having thus described my invention, 1 claim 1. A rotary engine comprising a casing, a cylinder eccentrically mounted therein and forming with the inner walls of said casing a chamber the area of which gradually increases from the inlet, then remains the same for a distance, and then gradually increases to the point of exhaust, pistons carried by the cylinder in contact with the walls of said casing and forming closed pockets therewith, an admission-port opening into the narrowest part of said chamber, and an exhaust-portopening into the widest part of said chamber.

2. A rotary engine comprising a casing, a cylinder eccentrically mounted therein and forming with the inner walls of said casing a chamber the area of which increases from the inlet to the point of exhaust, pistons carried by the cylinder in contact with the walls of said casing and forming closed pockets therewith, an admissionport opening into said chamber, an exhaust-port opening into said chamber, a rotary valve for regulating the inflow of the working fluid, and a slide-valve interposed between said rotary valve and the inlet to said chamber, and provided with a face contacting and cooperating with the external face of said rotary valve.

3. A rotary engine comprising a casing, a cylinder eccentrically mounted therein and forming with the inner walls of said casing a chamber the area of which increases from the inlet to the point of exhaust, pistons carried by the cylinder in contact with the walls of said casing and forming closed pockets therewith, an admission-port opening into the narrowest part of said chamber, an exhaust-port opening into the widest part of said chamber, a rotary valve for regulating the inflow' of the working fluid, and a slide-valveinterposed between said rotaryvalve and the inlet to said chamber and provided with a face contacting and cooperating with the external face of said rotary valve.

4. A rotary engine comprising a casing, a cylinder eccentricall y mounted therein and forming with the inner walls of said casing a chamber the area of which increases from the inlet to the point of exhaust, pistons carried by the cylinder in contact with the walls of said casing and forming closed pockets therewith, an admission-port opening into said chamber, an exhaust-port opening into said chamber, a rotary valve for regulating the inflow ofthe working fluid, a slide-valve interposed between said rotary valve and the inlet to said chamber, and a governor for regulating the movement of said slide-valve.

5. A rotary engine comprising a casing, a cylinder eccentrically mounted therein and forming with the inner walls of said casing a chamber the area of which increases from the inlet to the point of exhaust, pistons carried by the cylinder in contact with the walls of i said casing and forming closed pockets therewith, an admission-port opening into the narrowest part of said chamber, an exhaust-port opening into the widest part of said chamber, and an enlargement to said chamber extending from the inlet adapted to permit said pistons to present a greater area to the action of the working fluid.

6. A rotary engine comprising a casing, a cylinder eccentrically mounted therein and forming with the inner walls of said casing a chamber the area of which gradually increases from the inlet, then remains the same for a distance, and then gradually increases to the point of exhaust, pistons carried by the cyland forming closed pockets therewith, an admission-port opening into the narrowest part inder in contact with the walls of said casing of said chamber and extending into a wider portion, an exhaust-port opening into the widest part of said chamber, the distance between said ports being greater than the distance between adjacent pistons whereby the flow of working fluid to any of said pockets is cut ofl' before the exhaust is open and the fluid 1s caused to work expansively.

7. A rotary engine comprising a casing, a cylinder eccentrically mounted therein and forming with the inner walls of said casing a chamber the area of which increases from the inlet to the point of exhaust, pistons carried by the cylinder in contact with the walls of said casing and forming closed pockets therewith, an admission-port opening into the narrowest part of said chamber and extending into a wider portion, an exhaust-port opening into the widest part of said chamber, the dis tance between said ports being greater than the distance between adjacent pistons whereby the flow of working fluid to any of said pockets is cut off before the exhaust is open and the fluid is caused to work expansively, and an enlargement to said chamber near the steam-inlet adapted to permit said pistons to present a greater area to the action of the working fluid.

8. A rotary engine comprising a cylinder, a casing having a chamber therein the peripheral wall of which has two portions concentric to said cylinder one in contact therewith and one not in contact therewith and two portions eccentric to said cylinder one of which is intermediate said concentric portions and the other of which is intermediate the non-contacting concentric portion and the exhaustport, pistons carried by the cylinder in contact with said walls forming closed pockets therewith, an admission-port opening into the narrowest part of said chamber, an exhaustport opening into the widest part of said chamber, the distance between said ports being greater than the distance between adjacent pistons whereby the flow of the working fluid to any of said pockets is cut off before the exhaust therefor is open and the fluid is caused to work expansively.

9. A rotary engine comprisinga cylinder, a casing having a chamber therein the peripheral wall of which has two portions concentric to said cylinder one in contact therewith and one not in contact therewith and two portions eccentric to said cylinder one of which is intermediate said concentric portions and the other of which is intermediate the noncontacting concentric portion and the exhaustport, pistons carried by the cylinder in contact with said walls forming closed pockets therewith, an admission-port opening into the narrowest part of said chamber, and an exhaust-port opening into the widest part of said chamber.

10. In a rotary engine, a cylinder having a transverse groove in its face, a pivoted piston mounted in said transverse groove and arranged to alternately lie therein flush wlth the surface of the cylinder and to turn so as to extend an edge beyond said surface but always form with the walls of said groove a closed chamber, and means for admitting a working fluid into said chamber to cause a movement of said piston about said pivot.

11. In a rotary engine, a cylinder having a transverse groove in its face, a pivoted piston mounted in said transverse groove and arranged to alternately lie therein flush with the surface of the cylinder and to turn so as to extend an edge beyond said surface, members secured to said piston and always extending into said groove and forming with the walls thereof a closed chamber, and means for admitting a working fluid into said chamber to cause a movement of said piston about its pivot.

12. In a rotary engine, a cylinder having a groove in its face, a piston mounted in said groove and adapted to turn therein but al ways form with the walls of said groove a closed chamber, and means for admitting the working fluid into said closed chamber to cause the projection of a portion of said piston beyond the surface of said cylinder.

13. In a rotary engine having a roove in its surface, a piston mounted in said groove, an extension from the wall of said groove engaging the periphery of said piston, an exten sion on said piston engaging the wall of said groove, and means for admitting the working fluid between said extensions to project a portion of said piston outward beyond the face of said cylinder.

14. In a rotary engine, a cylinder having a groove in its face, and a piston mounted in said groove and adapted to turn to project a portion thereof outward. from the face of said cylinder said portion being provided with antifriction members extending longitudinally of the piston.

15. In a rotary engine, a cylinder having a groove in its face, a piston mounted in said groove and adapted to turn to project a portion thereof outward from the face of said cylinder said portion being provided with antifriction members extending longitudinally of the piston, and an abutment extending longitudinally of said piston between said antifriction members.

16. In a rotary engine, a cylinder having a groove in its face, a piston mounted in said groove and adapted to turn to project a portion thereof outward from the face of said cylinder, said portion being provided with antifriction members cooperating with the outer wall of said piston, and an abutment extending longitudinally of said piston between said antifriction members.

17. In a rotary engine, a cylinder having a groove in its face, a piston mounted in said groove and adapted to turn to project a portion thereof outward from the face of said cylinder, said portion being provided with antifriction members extending longitudinally of the outer surface of the piston near either edge thereof, an antifriction member in said cylinder and cooperating with said piston, and a working-fluid inlet communicating with the pocket between said members.

18. In a rotary engine, a cylinder having a transverse cylindrical groove in its face, and a semicylindrical piston mounted in said transverse groove rotatable about its axis, and arranged to alternately lie therein flush with the surface of the cylinder and to turn so as to extend an edge beyond said surface.

19. A rotary engine comprising a casing, a piston-carrying cylinder mounted therein and having a groove in its face, a rotatable piston mounted in said groove and having a surface adapted so as to lie flush with the periphery of said cylinder, and a longitudinal rib on said flush surface adapted to be operated upon by the working fluid to cause a portion of said piston to be projected outward from the face of said cylinder.

20. In a rotary engine, a casing member, a cylinder member eccentric to and cooperating with the inner wall of said casing memher, a groove in the operating-surface of one of said members, a piston mounted in said groove and adapted to turn therein but al- Ways form with the walls of said groove a closed chamber, and means for admitting a working fluid into said closed chamber to cause the projection of a portion of said piston beyond the surface of said cylinder.

21. In a rotary engine, a casing member, a cylinder member eccentric to and cooperating with the inner wall of said casing member, a groove in the operating-surface of one of said members, a piston mounted in said groove and adapted to always remain therein but to turn to project a portion of said piston beyond the working surface of said member, and means for admitting working fluid between the inner wall of said piston and the wall of said groove to cause said projection.

22. In a rotary engine, a cylinder having a transverse groove in its face, a pivoted piston mounted in said transverse groove and arranged to alternately lie therein flush with the surface of the cylinder and to turn so as to extend an edge beyond said surface but always form with the walls of said groove a closed chamber, means for admitting a working fluid into said chamber to cause a movement of said piston about said pivot, and means for cutting off the admission of said working fluid to said chamber.

23. In a rotary engine, a cylinder having a transverse groove in its face, a pivoted piston mounted in said transverse groove and arranged to alternately lie therein flush with the surface of the cylinder and to turn so as to extend an edge beyond said surface, members secured to said piston and always ex tendin into said groove and forming with the walls thereof a closed chamber, means for admitting a working fluid into said chamber to cause a movement of said piston about its pivot, and means for cutting off the admission of said working fluid to said chamber.

24. In a rotary engine, a cylinder having a groove in its face, a piston mounted in said groove and adapted to turn therein but always form with the walls of said groove a closed chamber, means for admitting the working fluid into said closed chamber to cause the projection of a portion of said piston beyond the surface of said cylinder, and means for cutting off the admission of said working fluid to said chamber.

25. In a rotary engine comprising a casing, a cylinder eccentrically mounted therein having a transverse groove in its face, a rotatable piston mounted in said groove, and adapted to project beyond the face thereof to contact with the inner walls of said casing, and a weight removably secured to said piston.

26. In a rotary engine comprising a casing, a cylinder eccentrically mounted therein having a transverse groove in its face, a.

rotatable piston mounted in said groove and adapted to project beyond the face thereof to contact with the inner walls of said casing, a chamber in said piston, and a weight secured in said chamber.

27. A rotary engine comprising a casing, a cylinder eccentrically mounted therein, pistons carried by the cylinder in contact with the inner walls of said casing, an admissionport opening into said chamber, an exhaustport opening into said chamber, a hollow cylindrical rotary valve provided with a plurality of openings for regulating the inflow of the working fluid, and also provided with a plurality of other openings for continuously admitting the working fluid to the interior thereof.

28. A rotary engine comprising a casing, a cylinder eccentrically mounted therein, pistons carried by the cylinder in contact with the inner walls of said casing, an admissionport opening into said chamber, an exhaustport opening into said chamber, a workingfluid reservoir, a valve for regulating the admission of the working fluid to said reservoir, and a valve interposed between said reservoir and the inlet to the narrowest part of said chamber.

29. A rotary engine comprising a casing, a cylinder eccentrically mounted therein, pistons carried by the cylinder in contact with the inner walls of said casing, an admissionport opening into said chamber, an exhaustport opening into said chamber, a workinguid reservoir, a valve for regulating the admission of the working fluid to said reservoir,

a hollow rotary valve inter osed between said reservoir and said cham er, and means for admitting to the interior of said valve the working fluid in said reservoir.

30. A rotary engine comprising a casing, a cylinder eccentrioally mounted therein and forming with the inner walls of said casing a chamber the area of which increases from the inlet to the point of exhaust, pistons carried by the cylinder in contact with the inner walls of said casing and forming closed pockets therewith, admissionports opening into the narrowest part of said chamber, recesses formed in the inner face of bridges between said inlet-ports forming abutments for the reaction of the working fluid, an exhaustport opening into the widest part of said chamber, and a valve for regulating theinflow of the working fluid.

31. A rotary engine comprising a casing, a cylinder eccentrically mounted therein, pistons carried by the cylinder in contact with the inner walls of said casing, admission-ports opening into said chamber, recesses formed in the face of bridges between said ports forming abutments for the reaction of the working fluid, an exhaust-port opening into said chamber, and a valve for regulating the inflow of working fluid.

32. In a rotary engine, a cylinder having a transverse cylindrical groove in its face, and a rotatable piston mounted in said groove and arranged to alternately lie therein. flush with the surface of the cylinder and to turn so as to extend either edge beyond said surface.

33. In a rotary engine comprising a casing, a cylinder rotatably mounted therein having a transverse groove in its face, a pivoted piston mounted in said groove and adapted to project beyond the face thereof to contact with the inner walls of said casing, and a weight removably secured to said piston.

Signed by me at Boston, Massachusetts, this 8th day of February, 1905.

WILLIAM N. MEARS.

Witnesses WALTER E. LOMBARD, EDNA C. CLEVELAND. i