US3589841A

US3589841A - Contaminant separation from a rotary vane pump

Info

Publication number: US3589841A
Application number: US6378A
Authority: US
Inventors: Carroll W De Lisse
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1970-01-28
Filing date: 1970-01-28
Publication date: 1971-06-29
Anticipated expiration: 1988-06-29

Abstract

A rotary pump of the sliding vane type is shown with a plurality of passageways located in the rotor of the pump to provide cleaned fluid for use as a lubricant, etc. The passageways are connected on one end to the pumping chambers of the pump and are designed to effectively store fluid trapped therein for a number of revolutions of the rotor, thereby permitting contaminant particles within the passageways to be centrifuged back into the main flow stream of the pump. Cleaned fluid is delivered to a chamber at the opposite end of the passageway from which it is used to maintain the sliding vanes in position and also as a lubricant.

Description

United States Patent Inventor Carroll W. De Lisse Cincinnati, Ohio Appl. No. 006,378

Filed Jan. 28, 1970 Patented June 29, 1971 Assignee General Electric Company CONTAMINANT SEPARATION FROM A ROTARY VANE PUMP Primary Examiner- Robert M. Walker Att0rneys Derek P. Lawrence, Thomas .1. Bird, Jr., Lee H. Sachs, Frank L. Neuhauser. Oscar B. Waddell and Joseph B. Forman ABSTRACT: A rotary pump of the sliding vane type is shown with a plurality of passageways located in the rotor of the pump to provide cleaned fluid for use as a lubricant, etc. The passageways are connected on one end to the pumping chambers of the pump and are designed to effectively store fluid trapped therein for a number of revolutions of the rotor, thereby permitting contaminant particles within the passageways to be centrifuged back into the main flow stream of the pump. Cleaned fluid is delivered to a chamber at the opposite end of the passageway from which it is used to maintain the sliding vanes in position and also as a lubricant.

PATENTEDJUN29|97I 3,589,841

sum 2 BF 2 v INVENTOR. CARROLL W. DELISSE AGENT- CONTAMINANT SEPARATION FROM A ROTARY VANE PUMP BACKGROUND OF THE INVENTION This invention relates generally to rotary vane pumps and, more particularly, to an apparatus for eliminating contaminant particles from such a pump.

Rotary expansion motors or pumping devices have been in use for many years. One common type of such pump works on a sliding vane principle. An eccentrically mounted rotor having radially outwardly extending vanes is located within a stator such that the vanes are resiliently urged against the inner wall of the stator to provide a complete seal between the wall and the vanes and to thus provide a plurality of variable volume chambers between each pair of adjacent vanes. Fluid is injected into the large volume chambers and is forced out as the volume of the chamber decreases with rotation of the rotor. The shaft of the rotor is normally coupled to an external source of power for driving the same.

In designing sliding vane-type pumps, designers manytimes utilize films of the fluid which is being pumped to support the various types of members located in the pumps which move relative to each other. For example, the sliding vane itself is occasionally provided with a film of the fluid in order tosubstantially eliminate friction between the vane and the rotor which is carrying it. When a fluidic film is utilized in such a manner, however, it is necessary to eliminate any contaminants in the film prior to such usage. Pump designers in the past have used mechanical barrier screens to eliminate contaminants from such fluidic films. These screens have a number of basic disadvantages, however, such as the requirement of periodic removal for cleaning and/or replacement. The use of such a screen also requires a preliminary design study to minimize the penalty imposed by holding capacity, initial cost, and cost of cleaning and/or replacement in terms of the flow range desired and the trapped particle size of the screen needed.

For the above reasons, various flow path configurationshave been devised to separate solid particles from fluids by utilizing the diflerent inertial characteristics of the particles. Devices of this type, however, invariably consume power from either the flow stream, a driving power source, or both. Such devices are also unpredictable over the large flow ranges occasionally associated with some pumping devices.

SUMMARY OF THE INVENTION It is an object of the present invention, therefore, to provide a continuous supply of decontaminated fluid for a rotary-type pump without the necessity of cleaning and/or replacing a filter unit.

It is a further object of the present invention to provide such an apparatus which has predictable operational characteristics over largeflow ranges and efficient separation characteristics over the entire range of operation.

Briefly stated, the objects of this invention are achieved by providing a plurality of passageways in the rotor of the rotary pump, which passageways are in fluidic flow cooperation with the expansion chambers of said pump. The passageways are designed to effectively store fluid trapped therein for a number of revolutions of the rotor. This permits centrifugal separation of particles carried by the fluid into the passageways and also permits the centrifuged particles to be discharged into the main flow stream of the rotary pump. The cleaned fluid is then discharged from the passageway into a cavity from which it can be routed to any desired location.

DESCRIPTION OF THE DRAWINGS While the specification concludes with claims particularly pointing out the subject matter of the invention which is sought to be covered, the invention may be understood from the following description of a preferred embodiment, given in connection with the accompanying drawings, in which:

FIG. 1 is an exploded view, partially broken away, of a sliding vane rotary pump constructed in accordance with this invention;

FIG. 2 is a cross-sectional view taken along line 2-2 of FIG.

FIG. 3 is an exploded view, partially broken away, of an alternative embodiment; and

FIG. 4 is a cross-sectional view taken generally along line 4-4 of FIG. 3.

DESCRIPTION OF A PREFERRED EMBODIMENT 7 Referring to the drawings wherein like numerals correspond to like elements throughout, a sliding vane-type rotary pump, generally designated by the numeral 10, is shown as comprising a first pressure plate 12, a second pressure plate 14, a rotor 16 and an eccentric stator 18. The rotor 16 comprises a solid cylindrical member having a plurality of radial slots 20 located therein. Suitably located for reciprocation within the slots 20 are a like number of sliding vanes 22.

The rotor 16 is positioned so that it is capable of rotation within the stator 18 as shown in both FIGS. 1 and 2. The stator 18 comprises a generally hollow cylinder having a noncircular, eccentric inner wall 24. As is best shown in FIG. 2, the wall 24 cooperates with the outer ends of the vanes 22 to provide a plurality of pumping chambers, generally designated by the numeral 26, which are of varying volume. Each chamber 26 is outlined by the sides of a pair of adjacent vanes 22, the wall 24, the outer surface of the rotor 16, and the pressure plates 12 and 14. The vanes 22 are maintained in sealed relationship with the wall 24 by some means in order to prevent the flow of fluid therebetween. The vanes 22 may be provided with suitable sealing members at their tips as is generally known.

The rotor 16 is provided with rotary motion by a suitable connection to an external source of power as through a spline 28 located within the rotor 16. Inlet fluid, generally designated by the arrows labeled I, enters the increasing volume between a pair of adjacent vanes 22 through inlets 30, provided in either the pressure plates l2, 14 or in the stator 18. In either case, the volume of the chamber 26 which is carrying the fluid remains constant while the fluid is trapped and transported to a discharge area where the volume between adjacent vanes 22 decreases and thereby forces the fluid to leave the pump 10 through ports 32 located in the pressure plate 12, one of which is shown in FIG. 1. The discharge fluid is shown schematically in FIG. 1 by the arrows labeled (D). The decreasing volume of the chambers 26 is provided by the eccentric shape of the wall 24, as is shown best in FIG. 2.

As thus far described, the pump 10 is of conventional construction with all of the elements thereof being known to those skilled in the art. In designing a sliding vane-type pump such as the one previously described, some means must be provided for maintaining the sliding vanes 22 in contact with the wall 24 at all times. Designers in the past have utilized spring members located within the slots 20 in some cases, andin other cases have utilized fluid pressure to maintain the vanes 22 in proper position. The present application, while not limited thereto, is especially suited for use with the latter-type design wherein fluid pressure is used to maintain the vanes 22 in sealed contact with the wall 24. The present invention is concerned with providing this fluid to the base of the vanes 22 for the abovedescribed purpose while at the same time eliminating contaminant particles from the fluid so that it is suitable forthe above purpose. In addition, this cleaned fluid may be used as a fllm to support the various kinds of members within a pump which move relative to each other.

In light of the above, the rotor 16 is provided with a plurality of passageways 34, shown being located between each pair of vanes 22. One end 35 of the passageway 34 is in fluidic flow cooperation with the chamber 26, as shown in FIG. I, while the opposite end 36 is in fluidic flow cooperation with a first conduit 37, a plurality of which are radially positioned within the pressure plate 14. The conduits 37 are, in turn, in fluidic flow cooperation with a number of second conduits 38, also located within the pressure plate 14 and spaced radially inwardly from the conduits 37. The conduits 38 are provided to deliver the cleaned fluid to the base of the slots 20 in order to maintain the vanes 22 in sealed relationship with the wall 24.

As shown in FIG. 1, a portion of the discharge fluid (D) will enter the passageways 34 instead of exiting through the ports 32. That portion of fluid which enters the passageways 34 is generally designated by the arrow (C). The passageways 34 are constructed with a volume that is sufficient to effectively store the fluid (C) for a number of revolutions of the rotor 16. The passageways 34 are also constructed at an angle which is sufficient to induce large angular accelerations and thereby cause a separating action to occur between the fluid (C) and relatively dense particles which may be entrained therein. Thus, rotation of the rotor 16 provides centrifugal separation of any particles which may have been carried by viscous action along with fluid (C) into the passageways 34. These particles are centrifuged back into the main discharge flow stream where they exit through the ports 32 along with the main discharge flow (D). Cleaned fluid (labeled E) is thus provided at the lower end of the passageways 36 and exits through the plurality of openings 36 within the rotor 16 from which it passes to the conduits 37 located within the pressure plate 14.

In addition to providing this cleaned fluid for pressing the vanes against the wall 24, the pump can also be made to deliver the cleaned fluid as a film to any other bearing members required for its operation. If desired, the cleaned fluid could also be provided to other devices, such as controlling valves, fluidic devices, or jet pipes which require clean fluid for best operation.

Referring now to FIGS. 3 and 4, an alternative form of rotary pump capable of utilizing applicants particle separation passageways is shown and labeled with the numeral 50. The rotary pump 50 includes an annular rotor or carrier member 52 having a plurality of slots 54 located therein which carry pumping elements 56 and which is surrounded by a cam member 58. The cam member 58 has an inner cam surface 60 along which the pumping elements 56 move as the rotor or carrier member 52 is rotated. The pumping elements 56 are preferably cylindrical members which are sized so as to be capable of movement radially inwardly and outwardly within the slots 54. This radial movement of the pumping elements 56 is caused by engagement with the cam surface 60 during rotation of the rotor member 52.

The pumping elements 56 are further sized so as to engage the sides of the slots 54 in a generally fluidically sealed manner. In this way, the slots 54 and the pumping elements 56 form a plurality of pumping chambers 62 which are of variable volume. As clearly shown in FIG. 4, the volume of the pumping chambers 62 decreases as the pumping elements 56 move radially inwardly within the slots 54, and increases as the pumping elements 56 move radially outwardly.

Referring now to FIG. 3, the rotor member 52 and the cam member 58 are surrounded by a pair of

end plates

64 and 65 which form the ends of the rotary pump 50. The

end plates

64 and 65 are connected to the cam member 58 by any suitable means in order to form the ends of the pumping chambers 62. The end plate 64 includes a pair of inlets 66 for delivering a fluid to the pumping chambers 62 at locations wherein the volume of the pumping chambers 62 is increasing, while the end plate 65 includes a pair of outlets 68 (one of which is shown) which receive fluid from the pumping chambers 62 during periods when the volume thereof is decreasing.

As further shown in the drawings, the rotor member 52 is further provided with a plurality of passageways 70, an inlet end 72 of which lies in communication with the pumping chambers 62 while an outlet end 74 lies within one face of the rotary member 52. The outlet ends 74 of the passageway 70 lie in communication with a chamber 76 formed within the end plate 64.

In operation, the rotor member 52 is coupled to a suitable source of external power which provides rotation thereto and fluid is delivered to the pumping chambers 62 through the inlets 66 formed in the end plates 64. As the rotor member 52 rotates, the pumping elements 56 engage the inner cam sur face 60 of the cam member 58 and are moved radially inwardly thereby. This causes an increase in the pressure of the fluid within the pumping chambers 62 until it exits through the pair of outlets 68 in the second end plate 65.

A portion of the fluid within the pumping chambers 62, however, will enter the inlet end 72 of the passageways 70 instead of exiting through the outlets 68. The passageways 70 (similar to the passageways 34 shown in FIGS. 1 and 2) are formed with a volume that is sufficient to effectively store fluid entrapped therein for a number of revolutions of the rotor member 52. Because of this, any contaminant particles which may have been carried by this viscous action into the passageways 70 will be centrifuged back into the pumping chamber 62 throughthe inlet ends 72 of the passageways 70. These contaminant particles will then be discharged through the outlets 68 along with the main discharge flow.

In this manner, a supply of cleaned fluid is provided at the outlet ends 74 of the passageways 70. This cleaned fluid may then be stored within the chamber 76 and utilized for any suitable purpose. For example, the cleaned fluid could be delivered to the area between the rotor member 52 and the cam surface 60 to act as a film to prevent friction between the cam surface 60 and the pumping elements 56. Also, as previously mentioned with respect to FIGS. 1 and 2, the cleaned fluid could be delivered to any fluidically operated member which requires contaminant free fluid.

The actual design of the

passageways

34 and 70 would, of course, depend upon the viscosity of the fluid which is being pumped and would also depend upon the size of the particles which are desired to be centrifuged. It can readily be seen from the above description that applicant has provided a simple source of cleaned fluid for use in any rotary pump. In addition, applicant has eliminated the need for periodic cleaning or replacement of presently used screens insofar as centrifuged particles are deposited right back in the main dischargestream of the pump and are thus eliminated from the pump. The operational characteristics of applicants pump are predictable over large flow ranges and separation efficiency would actually increase with diminishing, flow as the number of particles entering the passageways 34 would decrease with diminishing flow. While applicant's separation device has been shown in connection with two types of rotary pumps, it should be readily apparent that it would perform in a similar manner in any type of rotary pump. Such an operation would merely require the addition of a set of suitable cavities in any rotating member and a suitable means to extract the flow from the cavity or cavities. 1

What I claim as new and sought to be covered by Letters Patent of the United States is:

I. In a rotary pump having a rotor, a stator, a pumping chamber defined by the interaction of said rotor and said stator,

an inlet in fluidic flow cooperation with said pumping chamber,

an outlet in fluidic flow cooperation with said pumping chamber, the improvement which comprises at least one passageway located within said rotor,

said passageway having a first opening located at one end thereof and a second opening located at the opposite end thereof,

said first opening lying in fluidic flow cooperation with said pumping chamber,

said passageway being dimensioned such that particles entrapped therein are centrifuged into said pumping chamber,

thereby providing cleaned fluid at said second opening.

2. The rotary pump recited in claim 1 wherein said second opening lies in fluidic flow cooperation with a conduit which receives said cleaned fluid.

3. The rotary pump recited in claim 2 wherein said rotor comprises a cylindrical member having a plurality of radial slots located therein and a plurality of vanes located within said slots, said vanes being capable of reciprocal movement within said slots.

4. The rotary pump recited in claim 2 wherein said rotor comprises a cylindrical member having a plurality of radial slots therein and a plurality of pumping elements located within said slots,

said pumping elements being capable of radial movement within said slots, and

said pumping elements engaging the sides of each slot to thereby define a variable volume pumping chamber within each of said slots.

5. The rotary pump recited in claim 3 wherein said conduit lies in fluidic flow cooperation with said slots.

6. The rotary pump recited in claim 5 wherein said stator comprises a hollow cylindrical member having a noncylindrical, eccentric inner wall which surrounds said rotor,

said vanes being maintained in sealed engagement with said innerwall,

thereby providing a plurality of variable area pumping chambers, one of which is located between each adjacent pair of said vanes.

7. The rotary pump recited in claim 6 wherein said rotor includes a plurality of said passageways,

said passageways being provided between each adjacent pair of vanes.

8. The rotary pump recited in claim 7 wherein said cleaned fluid is utilized to maintain said vanes in sealed engagement with said inner wall.

9. The rotary pump recited in claim 7 further comprising bearing means associated with said rotor, wherein said cleaned fluid is delivered to said bearing means.

Claims

1. In a rotary pump having a rotor, a stator, a pumping chamber defined by the interaction of said rotor and said stator, an inlet in fluidic flow cooperation with said pumping chamber, an outlet in fluidic flow cooperation with said pumping chamber, the improvement which comprises at least one passageway located within said rotor, said passageway having a first opening located at one end thereof and a second opening located at the opposite end thereof, said first opening lying in fluidic flow cooperation with said pumping chamber, said passageway being dimensioned such that particles entrapped therein are centrifuged into said pumping chamber, thereby providing cleaned fluid at said second opening.

4. The rotary pump recited in claim 2 wherein said rotor comprises a cylindrical member having a plurality of radial slots therein and a plurality of pumping elements located within said slots, said pumping elements being capable of radial movement within said slots, and said pumping elements engaging the sides of each slot to thereby define a variable volume pumping chamber within each of said slots.

6. The rotary pump recited in claim 5 wherein said stator comprises a hollow cylindrical member having a noncylindrical, eccentric inner wall which surrounds said rotor, said vanes being maintained in sealed engagement with said inner wall, thereby providing a plurality of variable area pumping chambers, one of which is located between each adjacent pair of said vanes.

7. The rotary pump recited in claim 6 wherein said rotor includes a plurality of said passageways, said passageways being provided between each adjacent pair of vanes.