US3316814A - Rotary fluid pressure device - Google Patents

Description

y 2, 1967 L. CHARLSON 3,316,814

ROTARY FLUID PRESSURE DEVICE Filed April 22, 1965 3 Sheets-Sheet 1 1N VENTOR. .L'nwv L Czmacs'ov zrraen/zr May 2, 1967 L. CHARLSON 3,316,814

ROTARY FLUID PRESSURE DEVICE Filed April 22, 1965 5 Sheets-Sheet 2 rv- INVENTOR. A Zrmv L Usmzzs'a y 2, 1967 L. CHARLSON 3,316,814

ROTARY FLUID PRESSURE DEVICE Filed April 22, 1965 3 Sheets-Sheet 5 INVENTOR. Hg 6 .Zlnwv I. Czmzzsmr ATTOZ/VEV United States Patent Ofiice 3,316,814 ROTARY FLUID PRESSURE DEVICE Lynn L. Charlson, Minneapolis, Minn., assignor to Germane Corporation, Minneapolis, Minn, a corporation of Minnesota Filed Apr. 22, 1965, Ser. No. 450,113 4 Claims. (Cl. 91-56) ABSTRACT OF THE DISCLOSURE The device features an orbitably moveable, ring shaped valve disposed in a valve housing for feeding and exhausting fluid to and from expanding and contracting chambers. The orbital movement of the valve is synchronized with the chamber forming means and the valve sequentially provides communication (1) between the inlet port and the expanding chambers through the center of the ring valve and (2) between the outlet port and the contracting chambers through the region of the valve housiug which surrounds the ring shaped valve.

This invention relates generally to fluid pressure devices of the type having a gear reduction mechanism known in the art as a gerotor which forms expansible and contractible chambers.

A main object of the invention is to provide a new and improved gerotor type fluid pressure device having a new and improved valving system.

Other objects and advantages will become apparent from the following specification, appended claims and attached drawings.

In the drawings:

FIG. 1 is a longitudinal sectional view of a fluid pressure device embodying the invention, and taken on line I-I of FIG. 2;

FIG. 2 is an end View from the right end of FIG. 1;

FIG. 3 is a transverse sectional view taken on line III-III of FIG. 1;

FIG. 4 is a transverse sectional view taken on line IV-IV of FIG. 1;

FIG. 5 is a transverse sectional view taken on line V-V of FIG. 1.

FIG. 6 is a separate side view of a double eccentric member which is a part of the illustrated device;

FIG. 7 is an end view from the left end of the double eccentric shown in FIG. 6; and

FIG. 8 is an end view from the right end of the double eccentric shown in FIG. 6.

In the illustrated embodiment of the invention there is provided a casing comprising a generally cylindrically and annularly shaped shaft section 2, a cylindrically shaped gerotor section 4, a cylindrically and annularly shaped valve passage or valve plate section 5, a cylindrically and annularly shaped end cover plate 6 and a cylindrically shaped end cover plate 8. Casing sections 2, 4, 5 and end plate are held together in axial alignment by a plurality of circumferentially spaced bolts 10 which extend through casing sections 6, 5 and 4 and into casing section 2. End plate 8 is secured to casing section 2 with a plurality of circumferentially arranged bolts 14.

With reference to FIGS. 1 and 3, the gerotor casing section 4, which may be referred to as a ring member 4, has a plurality of internal teeth 16. An externally toothed star member 18, having at least one fewer teeth 20 than ring member 4, is disposed eccentrically in the chamber or space formed and surrounded by ring member 4. Star member 18 is moveable in an orbital path about the axis 24 of ring member 4. During orbital movement of star member 18 the teeth 20 thereof intermesh with the ring member teeth 16 to form expanding and contracting cells 25 to 30 which are equal in number to the number of teeth 20 of star member 18.

Casing section 2 has a bore 32 which is concentric relative to ring axis 24 and is of small enough diameter so that the resulting annular face 34 which abuts gerotor casing section 4, along with an annular face 36 of valve plate 5, form sides for the gerotor chamber so that the expanding and contracting cells 25 to 30 formed between the teeth of the gerotor star and ring members 18 and 4 will be closed for all orbital positions of the star member 18.

With further reference to FIG. 3, a vertical centerline 37 incidentally represents the line of eccentricity for the star member 18 for that particular position of the star member relative to the ring member 4. This line of eccentricity is defined herein as a line which is perpendicular to and intersects the star and ring axes 22 and 24 for all orbital positions of the star 18. During orbital movement of the star member 18, assuming the orbital movement is clockwise, the cells 25 to 37 on the left side of the line of eccentricity would be expanding and the cells 28 to 30 on the right side would be contracting. If the orbital movement were counterclockwise the reverse would be true. In the operation of the device illustrated, fluid under pressure is directed to the expanding cells on one side of the line of eccentricity and exhausted from the contracting cells on the other side of said line. The valving arrangement which facilitates the feeding and exhausting of the cells 25 to 30 will be described further on herein.

With reference to FIG. 1, the casing shaft section 2 has a cylindrically shaped counterbore 38 which is concentric relative to the centerline 24 which is also the centerline for ring member 4. A cylindrically shaped drive shaft 40 having a stepped portion 42 of larger diameter is rotatably disposed in the counterbore 38 and extends through a bore 44 in end plate 8. The shaft 40 may be driven by an electric motor or the like when the device is utilized as a pump or may drive apparatus such as a boat propeller when the device is utilized as a motor. Shaft 40 is provided with a bore 46 which opens into and is in axial alignment with casing bore 32, both bores being concentric relative to the device centerline 24.

Star member 18 has a bore 48 which is concentric relative to the axis 22 thereof. The left side of the star bore 48 is optionally provided with a plurality of circumferentially arranged, axially extending teeth or splines 50 and the left side of the shaft bore 46 also has a plurality of circumferentially arranged, axially extending teeth or splines 52. An intermediate shaft 54 is disposed between shaft 40 and star member 18 with the left and right ends of shaft 54 having splines 56 and 58 respectively which in each case are circumferentially arranged and extend axially. Splines 56 of shaft 54 are equal in number and mesh with splines 52 of shaft 40 and the same is true at the opposite end of intermediate shaft 54 wherein splines 58 of shaft 54 are equal in number and mesh with splines 50 of star 18.

Star member 18 is eccentrically disposed relative to ring member 4, as mentioned above, and intermediate shaft 54 is thus always in cocked or tilted position relative to shaft 40, which has the same axis as ring member 4, and the axis 22 of star member 18. In operation a star member 18 having six teeth will make one revolution about its own axis 22 for every six times the star member orbits in the opposite direction about the axis 24 of the ring member 4. Thus, the right end of intermediate shaft 54 has both orbital and rotational movement in common with the star member 18 while the left end of shaft 54 only has rotational movement in common with shaft 40. The spline connections between intermediate shaft 54 and shaft 40 and between intermediate shaft 54 a Si and star member 18 are forms of universal joints which permit shaft 54 to have the motion described above. When the device is utilized as a pump, star member 18 will be gyrated by a turning force applied to shaft 40 and transmitted to star member 18 through intermediate shaft 54. When the device is used as a motor, the force created by the rotation of star member 18 about its own axis 22 will be transmitted through intermediate shaft 54 to shaft 40 to cause turning of shaft 40.

End cover plate 6 is in abutting engagement with valve plate and has a bore 66 which may be concentric relative to the axis 24 of the device. Bore 60 defines a chamber which will be referred to as a valve chamber 61. Valve plate 5 has a plurality of axially extending, circumferentially arranged and spaced valve passages 62 to 68 (see FIGS. 1, 3 and 4) illustrated as being seven in number which is equal to the number of teeth of the ring member 4. Passages 62 to 68 are arranged at equal distances from axis 24 and extend from points between the ring member teeth 16, in the chamber formed by ring member 4, to the valve chamber 61 formed by easing bore 60. The shape of each passage 62 to 68 as illustrated has a cylindrical portion adjacent ring member 4 and is generally are shaped adjacent the valve chamber formed by the bore 60.

The wall of valve chamber 61 on the opposite side from valve plate 5 has an annular boss portion '70 which is concentric relative to axis 24 and is in general axial alignment with valve ports 62 to 68.

Disposed in valve chamber 61 is a ring valve 72 having two main parts concentric relative to the axis '73 of valve 72 which are an annulus 74 and a hub 75. A web portion 76 connects the hub and the annulus and has a series of circumferentially arranged openings 77. Annulus 74 has annular surfaces 78 and 79 on opposite sides thereof which are in slidable and abutting engagement respectively with valve plate 5 and annular box 70. The inside and outside diameters of ring valve annular surface 78 are predetermined so that annular surface 78 would be just suflicient to cover all the valve passages 62 to 68 if ring valve 72 were positioned concentrically relative to axis 24. Ring valve 72 cannot assume that position in the operation of the device, however, because ring valve 72 is disposed eccentrically in valve chamber 61 relative to axis 24- and in operation has an orbital path about the device axis 24.

Disposed between and connecting star 18 and ring valve 72 in driving relation is a crank 80 having two portions 81 and 82 which are concentric relative to the main axis of the crank and two axially spaced and angularly displaced crank portions 83 and 84 which are radially offset from the main axis of the crank. The main axi of crank 80 is coincident with the device axis 24 and the crank is rotatable relative to the casing of the device. Crank 80 is accommodated by several bores in different parts of the device which are a bore 85 on the right side of star 18 and concentric therewith, a bore 86 in valve plate 5 concentric with the axis 24 of the device, a bore 87 in the hub 75 of ring valve 72 concentric with the axis 73 of ring valve 72, and bore 88 in cover plate 6 concentric with axis 24 of the device.

Crank 80 has its two portions 81 and 82 rotatably mounted respectively in bores 86 and 88 of valve plate 5 and end cover 6 which are stationary members and these portions of the crank rotate about the axis 24. Crank portion 83 is rotatably disposed in the star bore 85 and crank portion '84 is rotatably disposed in the hub bore 87 of ring valve 72. During operation of the device the orbital movement of star 18 will cause rotation of crank 80 about axis 24 and the crank portion 84 will cause ring valve 72 to orbit in unison with star 18 Crank portion 84 is angularly displaced 90 degrees relative to crank portion 83 so that although the star 18 and ring valve '72 orbit in unison, the orbiting of the ring valve 72 will be 90 de grees out of phase relative to the orbiting of the star 13.

Stated another way, the line of eccentricity of the ring valve 72 (see FIG. 4) is displaced degrees relative to the line of eccentricity 37 of the star 18.

Casing section 6 is provided with inlet and outlet ports 92 and 93. Either of the ports 92 or 93 may be the inlet port depending on the direction of rotation desired for the shaft 40. For convenience, port 92 will be referred to herein as the inlet port 92 and port 93 will be referred to as the outlet port 93.

Ring valve 72 divides the valve chamber 61 into two noncommunicating chambers A and B which may be referred to as interior and exterior valve chambers and which are separated by the ring valve annulus 74. Fluid inlet port 92 is in fluid communication with interior valve chamber A and outlet port 93 is in fluid communication with exterior valve chamber B. Interior valve chamber A includes the spaces on both sides of ring valve web 76 in that the web openings 77 are provided to allow fluid to flow from fluid inlet port 92 to valve plate passages 62 to 68 and vice versa.

The orbital movement of ring valve 72 relative to the valve passages 62 to 68 is such that at any instant, as may be noted in FIG. 4, some of the passages open to the inside of the ring valve to the interior valve chamber A and some of the passages communicate with the exterior valve chamber B. At that instant, for example, passages 62 to 64 are in communication with the interior valve chamber A, valve passage 65 is covered by annulus 7'4, and passages 66 to 68 are in communication with the exterior valve chamber B. With reference to FIGS. 1, 3 and 4, assuming the star 18 and ring valve 72 to be in the positions shown in those figures, fluid being admitted through inlet port 92 flows to interior valve chamber A, through valve passages 62 to 64 to gerotor cells 25 to 27 which are expanding, from gerotor cells 28 to 30 which are contracting through valve passages 66 to 68 to the exterior valve chamber B and out through the fluid outlet 93.

The orbiting of star 18 causes ring valve 72 to be orbited by crank 80 at the same speed that star 18 orbits and in the same direction. The orbiting of ring valve 72 sequentially exposes valve passages on the left side of the line of eccentricity 37 to the interior valve chamber A and simultaneously sequentially exposes valve passages on the right side of the line of eccentricity to the exterior valve chamber B. As ring valve 72 orbits in unison with star 18, expanding gerotor cells on the left side of the line of eccentricity 37, which rotates about the axis 24 at the same speed that the star orbits about axis 24, will always be in fluid communication with the fluid inlet port 92 and contracting gerotor cells on the right side of the line of eccentricity will always be in tfluid communication with the fluid outlet port 93. In effect the ring valve 72 is indexed relative to the star 18 and, as the ring valve 72 and star 18 orbit in unison, the feeding and exhausting of the gerotor cells will always be on opposite sides of the line of eccentricity 37 for all orbital positions of the star 18 and ring valve 72.

It will be understood that the invention relates generally to the valving arrangement for feeding fluid to and exhausting fluid from the gerotor and in particular to the generally novel feature of providing a valve which performs the feeding and exhausting functions while moving in an orbital path. It is an essential characteristic of the invention that the orbital movement of the valve be in synchronism with the orbital movement of the star member but beyond that there are a number of ways that the invention may be used in practice.

An obvious modification is that the ring valve can have any angular displacement relative to the star member if the porting in the valve plate 5 separating the star and valve chambers is arranged so that the fluid feeding and exhausting is always on opposite sides of the line of eccentricity of the star member. If, for example, there were no angular displacement between the star member and the ring valve, the two ends of each of the ports in the valve plate could be displaced 90 degrees to achieve the same results. This would necessitate a rather complex porting arrangement for the valve plate and might be too costly to be practical but the principle of the invention could be practiced by providing such a porting arrangement.

If an arrangement were provided Where there would be no angular displacement between the star member and the ring valve, the crank member could be eliminated and the ring valve could be actuated by the intermediate shaft if the intermediate shaft were extended and connected to the ring valve. The extended portion of the intermediate shaft would move in an orbital path and if a universal joint type of sliding connection were provided between the extended shaft portion and the ring valve the ring valve would orbit in phase and in synchronism with the orbital movement of the star member.

Another obvious modification would be to eliminate or not provide the valve plate 5 between the star and valve chambers. The ring valve would be in direct abutting and sliding engagement with the gerotor ring and star members. In that construction, however, the ring valve would have to be angularly displaced 90 degrees relative to the star member as shown in the illustrated embodiment of the invention.

Another possible modification is that a drive shaft could be provided that rotates in synchronism with the orbital movement of the star member, as is known in the art, instead of a drive shaft that rotates in synchronism with the rotating movement of the star member as shown in the illustrated embodiment of the invention and which is also known in the art. If either type of drive shaft is provided the device will be suitable to function as a pump or a motor but a third alternative exists which is to provide no drive shaft at all in that case wherein the device may be used as a metering device which is also known in the art.

While one embodiment of the invention is described here, it will be understood that it is capable of modification, and that such modification, including a reversal of parts, may be made without departure from the spirit and scope of the invention as defined in the claims.

What I claim is:

1. In a fluid pressure device, fluid inlet and outlet means, casing means including an internally toothed ring member defining the outer wall of a chamber, a cooperating externally toothed star member having fewer teeth than said ring member disposed eccentrically in said chamber, one of said members having orbital movement about the axis of the other of said members and one of said members having rotational movement about its own axis in the opposite direction from and at a slower speed than said orbital movement during relative movement between said members, the teeth of said members intermeshing to form expanding cells on one side of the line of eccentricity and contracting cells on the other side of said line during relative movement between said members, valve means including a valve element, said valve means having fluid supply passage means for admitting fluid from said fluid inlet means to said expanding cells and fluid exhaust passage means for exhausting fluid from said contracting cells, and valve drive means for imparting orbital movement to said valve element in synchronism with said orbital movement of the orbiting one of said star member, wherein said valve means includes a valve chamber formed by said casing and said valve element is disposed eccentrically in said valve chamber, said valve element being ring shaped with one of said passage means being internally thereof and the other of said passage means being externally thereof.

2. In a fluid pressure device, fluid inlet and outlet means, casing means including an internally toothed ring member defining the outer wall of a chamber, a cooperating externally toothed star member having fewer teeth than said ring member disposed eccentrically in said chamber, one of said members having orbital movement about the axis of the other of said members and one of said members having rotational movement about its own axis in the opposite direction from and at a slower speed than said orbital movement during relative movement between said members, the teeth of said members intermeshing to form expanding cells on one side of the line of eccentricity and contracting cells on the other side of said line during relative movement between said members, valve means including a valve element, said valve means having fluid supply passage means for admitting fluid from said fluid inlet means to said expanding cells and fluid exhaust passage means for exhausting fluid from said contracting cells, and valve drive means for imparting orbital movement to said valve element in synchronism with said orbital movement of the orbiting one of said star member, wherein said star member and said valve element each has a centrally located bore, said valve drive means being a crank member which is rotatably and coaxially disposed relative to said ring member, said crank member having two eccentrically disposed crank portions angularly displaced degrees from each other, one of said crank portions being slidably disposed in said star member bore and the other of said crank portions being slidably disposed in said valve element bore.

3. A fluid pressure device according to claim 1 wherein a valve plate is disposed between said star and valve chambers, said valve plate having a series of ports arranged circumferentially relative to the axis of said ring member and extending through said valve plate to provide communication between said star and valve chambers, said ports being equal in number to the teeth of said ring member, said ports being spaced from the ring member axis a distance equal to about one-half the inside diameter of said valve element.

4. A fluid pressure device according to claim 3 wherein the shapes of said ports in the surface of said valve plate adjacent said valve chamber are are shaped.

References Cited by the Examiner UNITED STATES PATENTS 3,233,524 2/1966 Charlson 91--56 3,261,235 7/1966 Henkel 91-56 X 3,270,681 9/1966 Charlson 1 0 3-430 MARTIN P. SCHWADRON, Primary Examiner. G. N. BAUM, Assistant Examiner.

Claims (1)

1. IN A FLUID PRESSURE DEVICE, FLUID INLET AND OUTLET MEANS, CASING MEANS INCLUDING AN INTERNALLY TOOTHED RING MEMBER DEFINING THE OUTER WALL OF A CHAMBER, A COOPERATING EXTERNALLY TOOTHED STAR MEMBER HAVING FEWER TEETH THAN SAID RING MEMBER DISPOSED ECCENTRICALLY IN SAID CHAMBER, ONE OF SAID MEMBERS HAVING ORBITAL MOVEMENT ABOUT THE AXIS OF THE OTHER OF SAID MEMBERS AND ONE OF SAID MEMBERS HAVING ROTATIONAL MOVEMENT ABOUT ITS OWN AXIS IN THE OPPOSITE DIRECTION FROM AND AT A SLOWER SPEED THAN SAID ORBITAL MOVEMENT DURING RELATIVE MOVEMENT BETWEEN SAID MEMBERS, THE TEETH OF SAID MEMBERS INTERMESHING TO FORM EXPANDING CELLS ON ONE SIDE OF THE LINE OF ECCENTRICITY AND CONTRACTING CELLS ON THE OTHER SIDE OF SAID LINE DURING RELATIVE MOVEMENT BETWEEN SAID MEMBERS, VALVE MEANS INCLUDING A VALVE ELEMENT, SAID VALVE MEANS HAVING FLUID SUPPLY PASSAGE MEANS FOR ADMITTING FLUID FROM SAID FLUID INLET MEANS TO SAID EXPANDING CELLS AND FLUID EXHAUST PASSAGE MEANS FOR EXHAUSTING FLUID FROM SAID CONTRACTING CELLS, AND VALVE DRIVE MEANS FOR IMPARTING ORBITAL MOVEMENT TO SAID VALVE ELEMENT IN SYNCHRONISM WITH SAID ORBITAL MOVEMENT OF THE ORBITING ONE OF SAID STAR MEMBER, WHEREIN SAID VALVE MEANS INCLUDES A VALVE CHAMBER FORMED BY SAID CASING AND SAID VALVE ELEMENT IS DISPOSED ECCENTRICALLY IN SAID VALVE CHAMBER, SAID VALVE ELEMENT BEING RING SHAPED WITH ONE OF SAID PASSAGE MEANS BEING INTERNALLY THEREOF AND THE OTHER OF SAID PASSAGE MEANS BEING EXTERNALLY THEREOF.

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