US2498530A - Rotary pump - Google Patents

Description

Feb. 21, 1950 c. e. cooKE ROTARY PUMP Filed Sept. 18, 1943 mm W Patented F eb. 21, 1950 ROTARY PUMP Charles G. Cooke, Little Ferry, N. J assignor to Bendix Aviation Corporation, Teterboro, N. J. a corporation of Delaware Application September 18, 1943, Serial No. 502,988

3 Claims.

a rotary pump novel channel means for prevent ing the backing up of a fluid medium within the pump in opposition to movement of the rotor.

Another object of my invention is to provide a rotary pump having a novel rotor including a plurality of fluid impeller rollers carried thereby and movable under centrifugal force into contacting relation along the periphery of an eccentric wall surface for exerting thereby a force upon a fluid medium.

Another object of my invention is to provide novel magnetic means for biasing the rollers into contacting relation with the eccentric inner wall surface of the pump chamber for preventing leakage of said fluid medium through the pump.

Another object of my invention is to provide a novel rotary pump particularly adapted for use in the pumping of alcohol or other relatively non-compressible fluids.

Another object of my invention is to provide a novel pump for manufacture in minute size, of great efliciency in comparison to its size and particularly adapted for pumping in an aircraft of suitable ice inhibiting fluids for anti-icing units.

A further object of my invention is to provide a novel rotary pump having a minimum number of movable parts and. of such simplicity in construction as to adapt it for manufacture and installation at low cost.

Other objects and advantages of this invention are set forth in the following description, taken with the accompanying drawings; and the novel features thereof are pointed out in the appended claims. The disclosure, however, is illustrative only and I may make changes in detail, especially in matters of shape, size and arrangement of parts within the principle of the invention to the full extent indicated by the terms in which the appended claims are expressed.

In the accompanying drawings which form a part of this specification, like characters of ref- 2 erence indicate like parts in the several views, wherein:

Figure 1 is a sectional view taken along the line I-I of Figure 2 and looking in the direction of the arrows and with certain parts broken away so as to'better illustrate the invention.

Figure 2 is an end view of a rotary pump constructed in accordance with my invention and showing the rotary pump mechanism in dotted lines.

Figure 3 is a diagrammatic illustration showing the manner in which the wall surface of the eccentric pump chamber is determined.

Figure 4 is a fragmentary sectional view of the rotary pump taken along the lines 44 of Figure 1 and showing the pump rotor in a second ad-' justed position from that shown in Figure 2.

Figure 5 is a fragmentary sectional view of the eccentric pump chamber with the rotor removed.

Figure 6 is a similar view to Figure 5 with the rotor in place and illustrating a modified form of my invention showing a magnetic pump stator and diagrammatically the effects of the magnetic lines of force upon the rollers in holding the same in contacting relation with the wall surface of the pump chamber.

In the form of the invention shown in Figure 1 there is provided a casing or housing I having a flanged portion IA adapted to be mounted over the end of a suitable driving motor, not shown. Rotatably mounted in the housing I is a shaft 2, which has formed at the outer end thereof a head portion 3. The head portion 3 has provided internal splines 4 for connection to the drive shaft of the aforementioned motor.

The head 3 bears upon a portion'of a raised annular edge 5 of an antifrictional plate 6. The plate 6 rests upon an annular seat portion 1 formed within the housing I.

A bushing 8 is carried on the shaft 2 at the opposite side of the plate 5 from the head 3 and has mounted thereon antifrictional roller bearings 9 movable along a race way I0 provided within the casing I.

At the inner end of the shaft 2 there is concentrically affixed by a pin II a rotor I2. The rotor I2 has provided a center point I3 as best shown in Figures 3 and 4, and the same is rotatably mounted within an eccentric bore or pump chamber I4 formed in a disc-like stator member I5, as will be explained hereinafter.

Separating the rotor I2 and stator I5 from the bushing 8 and roller bearings 9 is a sealing plate I6 for preventing the leakage of fluid medium from the rotary pump chamber I4. A gasket l1 separates the sealing plate Hi from an annular shoulder portion l8 formed within the casing I and on which the same rests.

A second sealing plate I 9 is positioned at the opposite side of the rotor l2 and stator l5, and has provided a gasket 20 sealing the plate Is at the end of the housing I. An end plate 2| is fastened at the opposite side of the plate l9 by fastening bolts 22 which are engaged by suitable screw threads provided in the housing I. Mounted on the end plate 2| is a fluid inlet connector 23 leading into the rotary pump and arranged for connection to a suitable fluid medium supply conduit not shown.

There are also mounted on the end plate 2| fluid outlet connectors 24 and 25 leading from the rotary pump and arranged for connection to suitable fluid outlet conduits not shown.

As shown in Figures 1 and 2 oppositely disposed channels 26 and 21 formed in the housing I lead from the antifric'tional roller bearings 9, and provide a convenient outlet means for any fluid medium which might otherwise leak from the pump chamber l4 through the bearings 9 into the driving motor.

The eccentric pump chamber |4 provided in the stator l5, previously noted, is defined, as shown in Figure 3, by arcuate walls 28 and 29 formed at opposite sides of a. line Z-Z so as to provide a pair of lunate working chambers for a purpose which will be explained hereinafter. The greater part of the surface of the wall 28 is formed substantially on an arc of a circle having the center point 39, while the greater part of the surface of the wall 29- is likewise formed substantially on the arc of a similar circle having the center point 3|. The center points 3|! and 3| are positioned at opposite sides of and equally distanced from the center point i3 of the rotor l2, and the said center points are positioned along an imaginary line X-X extending at an angle of 90 degrees to the line Z-Z. As may be seen from Figure 3 imaginary lines YY and W-W, indicating the relative positions of the respective inlet and outlet ports to the pump chamber M, as will be explained hereinafter, extend at an angle of 45 degrees to the line X-X and extend at opposite sides thereof. All of the said lines pass through the center point l3 as shown.

The arcuate surface of the walls 28 and 29 of the pump chamber l4 have a radius from their respective center points 30 and 3| substantially equal to the radius of the rotor i2, except at such points as the arcuate surface of the walls 28 and 29 approach within a few thousandths of an inch of the circumferential surface of the rotor l2, as at the points indicated by the dotted lines A-A and B-B. Between the latter points the arcuate surface of the walls 28 and 29 are kept at only a few thousandths of an inch from the circumferential surface of the rotor I2 so as to assure a substantial seal against the passage of a fluid medium between the surface of the rotor I2 and the arcuate surface of the wall 28 extending between the points indicated by the lines 28-13 and Z-Z, and the arcuate surface of the wall 29 extending between the points indicated by the lines AA and Z-Z.

Drilled in the stator plate l are fluid inlet conduits 33 and 34 extending radially into the pump chamber l4 in longitudinal alignment with the imaginary line YY. Fluid outlet conduits 36 and 36 are likewise drilled in the stator l5 and extend radially from the chamber l4 in longitudinal alignment with the imaginary line W-W.

The outer ends of the conduits 33, 34, 35 and 36 are closed by suitable screw threaded plugs 31, 38,- 39 and 40, respectively.

Ducts 4| and 42, as shown in Figure 1, are drilled from one side of the stator I5 at right angles into the inlet conduits 33- and 34. Further ducts 43 and 44 are drilled through the plate i9 and open at one end thereof into the ducts 4| and 42, respectively, and open at the opposite ends into a channel 45 formed in the end plate 2|. Thechannel 45 is closed at one end and opens at the other end into the fluid inlet conmotor- 23 provided on the end plate 2|, as previously described. Thus, it will be seen that a supply of fluid medium may be conducted to the chamber |4 through the inlet conduits 33 and 34.

Ducts 46;,and 41, as indicated in dotted lines in Figure 2, .are likewise drilled in the stator l5 at right angles into the outlet conduits 35 and 36, and lead into suitable ducts 48 and 49 formed in the endvplatev l9. The ducts 48 and 49 open at the opposite end into outlet connectors 24 and 25, respectively, provided on the end plate 2|. Thus fluid medium under pressure may be conducted from the'pump chamber M.

In order to exert a suitable force upon the fluid medium supplied to the chamber l4 through the inlet conduits 33 and 34, the rotor I2 has provided a plurality of radial slots 50 in each of which is rotatably mounted a fluid impeller roller indicated by the numeral 5|. The rollers 5| under centrifugal force, resulting upon rapid rotation of the rotor l2, are forced radially outward from the slots 50 so as to contact the eccentric wall surface of the chamber I4 and wipe the walls of the lunate working chambers, previously described, as the rotor turns. The rollers 5| reciprocate in the slots 59 so that the same follow the eccentric contour of the chamber I4. Moreover, it will be seen that the rollers 5| are arranged in pairs of oppositely positioned rollers, which simultaneously force the fluid medium from the oppositely positioned outlet conduits 35 and 36. In the instant embodiment of the invention the rotor I2 is arranged to rotate in a clockwise direction as indicated by the arrow in Figure 4. Thus as each of the impeller rollers 5| pass the opening of the fluid inlet conduits 33 and 34 a quantity of the fluid medium will be entrapped and impelled through the innate shaped working chambers and out the next succeeding outlet conduits 35 and 36, respectively.

- A groove or channel 52 is formed in the surface of the wall 29 and connected to the inlet conduit 33, while a second groove 53 is formed in the surface of the wall 28 and connected to the inlet conduit 34. It will be seen that the grooves 52 and 53 extend in a clockwise direction from the respective inlet conduits 33 and 34, and in the direction of rotation of the rotor |2 so as to increase the supply of the fluid medium to the impeller rollers 5| as the same pass the inlet port. The channels 52 and 53 are so arranged with relation to the outlet ports 35 and 36 that upon the pumping rollers 5| passing the end of the channels 52 and 53 so as to close the inlet ports 33 and 34, respectively, to the working chamber immediately preceding each of the said pumping rollers 5|, the rollers 5| at the opposite end of the said chamber will open the next succeeding outlet port 35 and 36, respectively, to such chamber so as to prevent the fluid medium contained therein from opposing the rotar movement of the rotor l2, as would otherwise result upon the fluid medium being forced into a space of decreasing cubic content.

Moreover other grooves or channels 54 and" 55 are cut in the surface of the walls 29 and 28 extending from the outlet channel 35 and 35, respectively, in a clockwise direction and in the direction of rotation of the rotor I2.

As shown in Figure 3, the channel 54 extends from the outlet conduit 35 to the point on the surface of the wall 29 indicated by the line Z, while the channel 55 extends from the outlet conduit 36 to the point on the surface of the wall indicated by the line Z. As previously indicated since the circumferential surface of the rotor l2 and the surface of the chamber M between the points indicated by the lines AA and 3-3 are separated by but a few thousandths of an inch so as to provide a substantial seal between the same, fluid medium between the successive rollers will not be carried past the end of the channels 54 and 55. Without such channels 54 and 55, it may now be readily seen that movement of the impeller rollers 5| past the outlet conduits 35 and 36 would cause the remaining fluid medium between successive rollers to be forced in to a space of decreasing cubic. content so as to cause an increasing opposition to movement of the rotor l2. Under the latter conditions the increasing pressure on the fluid medium, par-- ticularly in the case of alcohol or other relatively non-compressible fluids, must be relieved in some manner. Thus in the latter case the fluid under force of the impeller rollers would leak back past the rollers, pushing them away from the eccentric wall against centrifugal force so as to thereby partially defeat the intended mode of operation of the device and increase the work required of the motor means driving the same.

However, by providing the novel channels 54 and 55 such opposing action does not take place.

In the case of the channels 54 and 55, as shown in Figures 1 through 5, after the pumping roller 5| has passed the outlet port the continued pressure increase is relieved through the channels 54 and 55, respectively, and the fluid conducted by the channels 54- and 55 added to the previous flow.

The. combination of the added. flow thus obtained and the reduced work required of the driving means per unit of fluid flow increases the efliciency of the pump most materially.

In the operation of the pump, the rotor l2 turns in a clockwise direction, and as the rollers 5| move past the inlet ports 33 and 34, respectively, the lunate chambers between the pumping rollers and the next roller preceding each of the pumping rollers increases in cubic content in such a manner as to draw the fluid medium into such chambers through the ports 33 and 34 until the pumping rollers 5| reach the end of grooves 52 and 53, respectively, at which point the cubic content of such chamber between the pumping roller and the next succeeding roller is at a maximum. Further rotary movement of the rotor I! then causes the said preceding rollers 5| to open such lunate chambers to the outlet conduits 35 and 36, respectively, whereupon the entrapped fluid medium is forced out the respective outlet conduits under force of the impeller rollers 5|, which exert a decreasing biasing effect upon the fluid medium until the end of channels 54 and 55, respectively, have been passed by the pumping rollers 5|. The pumping rollers 5| then upon passing the point of seal between the rotor l2 and the chamber l4, as previously described, once again become a pumping roller on approaching the succeeding inlet ports 34 and 33, respectively, and the cycle of operation repeats itself as may be readily seen from Figure 4.

Further, it will be noted thatin the operation of my novel rotary pump, the impeller roller which has immediately passed the outlet port provides through the action of the channels 54 and 55 an additional flow of fluid to the outlet port at a time when the flow of fluid medium impelled by the immediately succeeding roller has not reached its maximum value, thereby tending through the additional supply of fluid medium to more nearly approximate at the outlet channel a constant flow of fluid with a minimum loss in efficiency through opposition of the fluid medium,

Moreover by providing the impellers 5| in the form of rotatable rollers, radial movement of the impellers in relation to the rotor l2 and movement of the same along the inner periphery of the eccentric pump chamber may be accomplished with minimum frictional losses.

Further from the foregoing, it will be seen that each impeller roller performs two cycles of operation or pumping operations for each rotation of the rotor l2 and as six impeller rollers are shown, there must necessarily be twelve pumping operations for each rotation of the rotor 2 so as to thereby provide a more constant flow of fluid medium and efllcient operation of the pump. Although six impeller roller are shown in the preferred' form of the invention, the pump may be constructed to operate with a somewhat similar efl'ect with two or more impeller rollers.

I have further shown in Figure 6, a modified form of stator which may be used. The modified form of stator indicated by the numeral I00 is of like form to the stator I2 except that the stator I00 comprises a permanent magnet which may be substituted for the stator l2.

In Figure 6, the north and south magnetic poles are indicated by the letters N and S, re-

spectively, and it will be seen that the magnetic lines of force of the magnetic stator I00 will tend at all times to hold rollers 5|, formed of a suitable ferromagnetic substance, in engaging relation with the eccentric surface of the pump chamber l4. Thus the magnetic stator I00 will tend to reduce leakage and loss of fluid pressure, which might otherwise result through the fluid medium seeping past the rollers 5|, and further assures the positioning of the rollers 5| in contacting relation at all times with the eccentric surface of the pump chamber with minimum frictional losses. Thus an efllcient pumping action may be effected at a lower rate of driving speed of the rotor II. In the latter form of my invention, the rotor l2 and the sealing plates l6 and I!) are preferably formed of a suitable nonmagnetic material to assure the maximum effect of the ,magnetic stator on the rollers 5|.

Although only two embodiments of the invention have been illustrated and described, various mounted in said housing and having an eccentric 2. A rotary pump, comprising, in combination,

a magnetic stator, a bore formed in said magnetic stator having oppositely positioned eccentric wall surfaces and magnetic poles at opposite ends of the bore, each of said wall surfaces formed on the arc,of a circle, the center points of said circles being spaced apart and positioned in alignment, a circular shaped rotor positioned in said bore and forming with said eccentric wall surfaces a pair of lunate shaped working chambers, the circular shaped rotor being positioned so as to form a substantial seal at the opposite ends of said lunate shaped working chamber with the wall of said bore, a pair of fluid inlet conduits extending radially into said bore in opposite relation, one of said inlet conduits leading into an end of one of said lunate shaped working chambers and the other of said inlet conduits leading into an end of the other of said lunate shaped working chambers, a pair of fluid outlet conduits extending radially from said bore in opposite relation to each other, and said outlet conduits extending at an angle of ninety degrees to said inlet conduits and forty-five degrees to the aligned center points of said eccentric wall surfaces, one of said outlet conduits leading from an end of one of said lunate shaped working chambers and the other of said outlet conduits leading from an end of the other of said lunate shaped working chambers, said rotor having a plurality of radial slots formed therein, a plurality of impeller rollers rotatably mounted in said slots, and said impeller rollers rotatably contacting the surface of said eccentric bore, said impeller rollers movable in said lunate shaped working chambers in the direction of said outlet conduits for simultaneously forcing a fluid medium from'each of said working chambers and out said outlet conduits and said magnetic stator attracting said impeller rollers into contacting relation along the inner periphery of said eccentric bore so as to maintain said rollers in substantial sealing relation along the inner periphery of said bore.

3. A rotary pump, comprising, in combination, a housing having a bore formed therein at one end, a permanent magnet in the form of an annular member having opposite magnetic poles at opposite ends thereof, said member positioned in said bore and having oppositely positioned eccentric inner wall surfaces, each of said inner of lunate shaped working chambers, the circular shaped rotor being positioned so as to form a substantial seal at the opposite ends of said lunate shaped working chamber with the wall of said annular member, a pair of fluid inlet conduits extending radially in said annular member in opposite relation, one of said inlet conduits leading into an end of one of said lunate shaped working chambers and the other of said inlet conduits leading into an end of the other of said lunate shaped working chambers, a pair of fluid outlet conduits extending radially in said annular member in opposite relation to each other, and said outlet conduits extending at an angle of ninety degrees to said inlet conduits and fortyflve degrees to the aligned center points of said eccentric wall surfaces, one of said outlet conduits leading from an end of one of said lunate shaped working chambers and the other of said outlet conduits leading from an end of the other of said lunate shaped working chambers, an end plate fastened to said housing at said one end and closing said bore, a shaft extending through the opposite end of said housing and operably connected to said rotor, said rotor having a plurality of radial slots formed therein, a plurality of impeller rollers rotatably mounted in said slots, and said impeller rollers rotatably contacting the eccentric inner surface of said annular member, said impeller rollers movable in said lunate shaped working chambers in the direction of said outlet conduits for simultaneously forcing a fluid medium from each of said working chambers and out saidoutlet conduits, axially extending fluid inlet and outlet connectors mounted on said end plate and opening'into said radial inlet and outlet conduits respectively, and said magnetic member attracting said impeller rollersinto contacting relation along the inner periphery of said annular member so as to maintain said rollers in substantial sealing relation along the inner periphery of said member.

CHARLES G. COOKE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,271,585 Klise July 9, 1918 1,666,466 Peters Apr. 1'7, 1928 2,135,881 'Wentworth Nov. 8, 1938 2,255,785 Kendrick Sept. 16, 1941 2,268,804 Curtis Jan. 6, 1942 2,321,190 Ellinwood June 8, 1943 2,373,457 Chisholm, Jr. Apr. 10, 1945 2,378,390 Bertea June 19, 1945 FOREIGN PATENTS Number Country Date 21,256 GreatBritain Oct. 19, 1905 235,095 Great Britain June 11, 1925 450,669 Great Britain July 1'7, 1936 459,230 Great Britain Jan. 4, 19.37 663,116 France Mar. 29, 1929 681,601 France Feb. 3, 1930

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