US2762312A

US2762312A - Vane type pump

Info

Publication number: US2762312A
Application number: US226844A
Authority: US
Inventors: Cecil E Adams; John R English
Original assignee: Denison Engineering Co
Current assignee: Denison Engineering Co
Priority date: 1951-05-17
Filing date: 1951-05-17
Publication date: 1956-09-11
Anticipated expiration: 1973-09-11

Description

Sept. 11, 1956 ADAMS ET AL 2,762,312

VANE TYPE PUMP 3 Sheets-Sheet 1 Filed May 17, 1951 \,\\\\7IIIIIIIIIII,

FIG 5 JNVENTORS Sept. 11, 1956 c, ADAMS ET AL 2,762,312

VANE TYPE PUMP Filed May 17, 1951 3 Sheets-Sheet 2 mmvrozas Cecil E.Ad.ams John R.Engli sh Sept. 11, 1956 c. E. ADAMS ET AL VANE TYPE PUMP 3 Sheets-Sheet 3 Filed May 17, 1951 FIG. 5.

IN VEN TORS Cecil E.Adgms 4 JohnR. fla -W6 Englxsh, W

Unite States Patent This invention relates generally to hydraulic apparatus and is more particularly directed to an improvement in fluid pressure energy translating devices which may' be used either as pumps or motors.

An object of this invention is to' provide a fluid or motor of the vane type which will operate more 'efiiciently than prior devices of this character and one which Will give longer service with a minimum of attention.

Another object of this invention is to provide a vane type fluid pump or motor capable of generating, or being driven by fluid under relatively high pressures, the device being formed with means for creating an intermediate fluid pressure in the spaces defined by the vanes in their movement from the inlet to the exhaust port and vice versa whereby pulsation and consequent noise together with stresses on the vanes will be reduced, the life of the device thus being prolonged.

A further object of the invention is to provide a'van'e type fluid pump or motor having means for utilizing fluid pressure to reduce friction and consequently wear between the rotor and the casing of the device during its operation,

thus increasing the efliciency of the device arid lengthening its active life.

A still further object of the invention is to provide a vane type fluid pump or motor having a casing with a rotor chamber and a rotor with radial slots for receiving vanes, the latter having grooved outer edges for engaging a cam track having concentric portions of diflferent radii connected by angular portions, the vanes also having passages extending from the grooved outer edges to the inner edges so that fluid pressures will be substantially balanced on the inner and outer ends of the vanes, springs being provided to urge the vanes outwardly into contact with the cam track surfaces, the grooved outer edges of the vanes providing two sealing engagements at each vane as it passes along the concentric portions of the cam track to decrease the leakage and to provide a valving action between the port opening and the bottom of the vanes when the vanes are moving across the angular connecting portions of the cam track. 7 v

Another object of the invention is to provide avane type pump or motor having a casing with a rotor chamber and a rotor disposed therein, the sides of the rotor being disposed in close relationship to the sides of the chamber these members being provided with grooves and passages to prevent leakage of pressure fluid on either side from crowding the rotor against the other side. I s

An object also is to provide a vane typepump or motor havin'g a casing with a rotor chamber and a rotor disposed therein, certain of the engaging side walls havinglealgage collecting grooves, therotor having passages to connect predetermined grooves at opposite sides :of the rotor so that'pre'ssure' fluid leaking between the side walls at one side of the rotor will be conducted to the other side thereof, the grooves being of ditferent' areasin order to cause an increased force to be exerted at one side to uickly overcome the force on the other side. Si nce the 'i'otoris symmetrical the 'end res ult' will be the centerice high thereof in the rotor chamber with equal clearance on both slides. I

It is also an object of the invention to provide a vane type pumpfhaving' a rotor member with slots for the vanes and recesses between adjacent slots whereby increased communication area will be secured between the pockets formed by the rotorand vanes and the inlet and outlet po s when the pockets register therewith to the end that thelowes't velocity of fluid flow from ports to pockets and vice versa will occur, the recesses in the rotor being so shaped that maximum support will be provided for the vanes. I

Further objects and advantages of the present invention will be apparent from the following description, reference hang had to the accompanying drawings.

In the drawings: r t

Fig. lis a longitudinal sectional view taken through a or motor formed in accordance with the present invention Fig. '2 is a vertical transverse sectional view taken through the pump or motor on the plane indicated by the line II- II of Fig. 1. v I

Fig; 3' is a horizontal sectional view taken through the motor on the plane indicated by the line III- H1 of Fig. 1.

Fig. 4 is a fragmentary transverse. sectional View taken on the lane indicated by the line 1v ;1v of Fig. 1.

Fig. 5 is" 'a detail sectional view taken through the motor on the plane indicated by the lined V of Fig.4. Fig; 6 'is a vertical transverse sectionallview taken through the device on the plane indicated by the line v vr of' Fig; 1. H V p 7 Referring more particularly to the drawings the iin proved vane type pump and motor is designated generally by the numeral 20. This pump includes a casing 21 Whic-h'is formed from a pair of

end sections

22 and 23 anda central section 24, these sections being bolted or otherwise secured together by members 25 to form a unitary casing having an internal rotor chamber 26'. As shown inFig's. 2 and 3, the chamber is formed primarily by thecenter section 24 which section is somewhat ringlike in form, the center opening, however, being substantially oval; the purpose of this shape will be apparent from thefoll'owing description. The ends of this ring are close'd by the

end sections

22 and 23 to complete the chamber.

The

sections

22 and 23 are provided aslshown in Fig 1 with inlet and

outlet openings

27 and 28, these openings each communicating with the chamber 23 at two diametrically

opposite places

31 and 32, the points of

communication

31 and 32 being hereafter termed inlet and outlet ports. The inlet ports 31 extend from inlet opening 27, while the outlet ports 32 extend from opening 28.

Ports

31 and 32 are disposed at of revolution from one another. This arrangement provides alternate inlet and outlet ports spaced at 90 around the chamber 26. Ports 3 1 are disposed at one end of the chamber 26 while ports 32 are disposed at the opposite end. Section24 is pro vided'with a plurality of openings 33in registration with the ports 31 and 3 2, these openings. extending through the section 24 to establish communicationbetween the p'or'ts'3l' and 32 and recesses 31A and 32A formed in the other end section in registration with the ports.

Section 22is provided with a central opening for, the rekieistir. n of bearing elements 34 which rotatably support a shaft 35, one end of this shaft projecting through the chamber 26"a'nd the other end to the exteriorof the casing as 'atj36. This end is provided with a key 37 to secure a pulley or other suitable element (not shown) for rotation with th shaft. The inner end as of the shaft is providedwith splines which are received within keyways provided in a rotor body 41, this body being substantially circular, when viewed from the end as in Fig. 2, and

having a diameter slightly less than the length of the minor axis of the oval chamber 26.

The body 41 has a plurality of radially extending slots 42 formed therein, these slots receiving vane elements 43. The vanes 43 closely fit the slots 42 but are movable in a radial direction therein. As shown in Figs. 1, 2 and 3, the body 41 is provided at the lower end of each slot with a plurality of sockets 44 for the reception of coil springs 45 which tend to urge the vanes in an outward direction, the springs also being received Within sockets 46 formed in the vanes in registration with the sockets 44. The vanes are further provided with passages 47 establishing communication between the inner ends of the slots 42 and the chamber at the outer periphery of the rotor body. The vanes also have grooved outer end and side edges 48 and 59, the groove 48 being provided for a purpose which will be set forth later. It will be noted from Fig. 2 that the groove 48 in the outer edge of each vane provides such vane with spaced contact edges 52 which in certain positions of the vane engage the inner surface of the section 24 at spaced lines of contact. These edges and the groove thus provide a small chamber which is connected by the grooves 50 and ports 47 with the inner ends of the slots 42. It will be obvious that the pressure existing in the slots 42 Will also exist in the chamber formed by the groove 48 and vice versa.

Contrary to the true definition of an oval the chamber 26 has spaced portions which are truly concentric with the axis of the shaft 35 the portions of the surface at opposite sides of the inlet and the outlet ports being spaced at different distances from the axis of the shaft 35. The portions spaced the greater distance from the axis extend between inlet and outlet ports and provide fluid transfer sections while the other concentric portions provide sealing sections; the purposes of these sections will be apparent from the following description.

It will be noted from Fig. 2 that the rotor body 41 is provided, between adjacent slots, with relieved portions 53, these portions increasing the size of the pockets between adjacent vanes thus permitting the use of larger inlet and outlet ports whereby the velocity of the fluid flowing into and out of the pockets during the operation of the device will be materially reduced. This construction has been found desirable due to the rapid rate at which the rotor revolves during some periods of use of the motor. It also helps to prevent cavitation when the device is used as a pump. Fig. 2 shows also that when the vanes move along the angular portion of the cam surface connecting the sealing sections of the chamber and the transfer sections, the edges 52 of the vanes are alternately spaced from such surface depending upon whether the vanes are moving from the transfer section to the sealing section or vice versa.

During this time when one or the other edge is spaced from the chamber surface, which surface may be designated as a cam surface, the vanes are moving across either an inlet or an outlet port. At this time it is not necessary for the vane to provide a sealing action between adjacent pockets since fluid at the same pressure is disposed on each side of the vane.

The spacing of one or the other edge from the cam surface during the travel of a vane over the angular connecting portion is desirable and advantageous since it provides an avenue for the fluid to flow into and out of the passages leading through the vane to the inner end of the slot in the rotor. The spaced outer edges of the vanes thus serve as valves which are closed when the vanes are in engagement with the concentric portions of the cam surface and open when the vanes are in engagement with the angular connecting portions of the cam surface which causes the vanes to move in and out. As soon as the vanes reach the concentric surface of the transfer or sealing sections both edges will be engaged with the cam surface and a double seal will again be etfected. At this time also the grooved outer edges of the vanes are sealed off from the pockets at either side thereof. The grooved outer edge of each vane then communicates with the inner end of the slot and the areas exposed to pressure will thus be substantially equal at the inner and outer edges of the vane except for the small portions of the vane in actual contact with the cam surface. The vanes will, therefore, be substantially balanced, being urged outwardly into engagement with the cam surface only by the force of the springs and the centrifugal force. A minimum amount of wear on the cam contacting surface will result.

It has also been found desirable to eliminate as much as possible any side thrust on the rotor which might cause the parts to wear or oppose the rotation of the rotor and thus decrease the efliciency of the device. Side thrusts may be caused by leakage of fluid under high pressure between either side of the rotor and the side wall of the adjacent end member. To counteract this tendency the end members are provided with

concentric grooves

54 and 55 the first groove being the outer one which is relatively narrow and has a small area, the second being the inner groove which is wider and has a greater area. These grooves are located between the inner ends of the vane slotsand the axis of rotation of the shaft so that the grooves will not directly communicate with such slots. When fluid under pressure is introduced into the inlet ports and the pockets between the vanes to effect the operation of the motor some of this fluid may tend to seep toward the axis of rotation between the side walls of the rotor and the

end sections

22 and 23 at one side or the other of the rotor; this fluid will be collected by the groove 54 on that particular side before it can exert any great force to move the rotor toward the opposite side wall. Grooves 54 are connected by angularly extending passages 56 with the inner grooves 55 at the opposite sides of the rotor. Since the grooves 55 are of greater area than the grooves 54 the fluid under pressure flowing thereto will exert a greater force tending to move the rotor in the opposite direction which force will counteract the tendency of the fluid at the opposite side to move the rotor. Since the total widths of the groves at both sides are equal the rotor will be centered in the rotor chamber and the least amount of leakage between the rotor and the chamber walls will be encountered.

From Figs. 1 and 6 it will be noted that slots 56A of reduced Width extend from the inner grooves 55, or the adjacent ends of the angular passages 56, to the space surrounding the shaft 35 which is connected, as will hereinafter be set forth, with exhaust. The slots 56A provide for the drainage of fluid that leaks past the rotor and is collected by the

grooves

54 and 55. These slots are relatively narrow so that they will not interfere with the primary purpose of the

grooves

54 and 55, i. e., of centering, by the force of fluid pressure leakage, the rotor in its chamber.

It has been found that pulsation of discharge, shock of operation and consequent wear may be reduced by equalizing the pressure in the pockets between the vanes as these pockets move from one port to another. This operation is performed by connecting all of the pockets located midway between adjacent inlet and outlet ports. From Fig. 2 it will be observed that when the pockets are located at these points the vanes at either side of the pockets completely seal the pockets from the inlet and outlet ports. It will also be noted that since there are four ports, four pockets will be sealed from such ports at the same time. One end member is provided with angularly directed passages 57 as disclosed in Figs. 4 and 5 which connect chamber 26 with a groove 58, this groove being formed in the member 22 aroundthe opening for the inner bearing 34. This bearing serves to complete the groove into an annular passage. With this construction the annular passage 58 is connected with the chamber as shown in Fig. 4, at four points spaced apart, which points are disposed midway between outletports 32 and recesses 31A which are connected with the inlet ports 31. Asshown in'Figsv 5 and 6 the rotor has inwardly extending radial slots 60 at the inner edges of the relieved portions 53. It will be obvious that when the rotor is disposed as in Fig. 2 the pockets in the transfer sectionswill be connected with the pockets in the sealing sections, through the slots 60 and

passages

57 and 58. As the pockets move from the inlet port to the position shown in Fig 2 in the transfer section they will carry fluid at the inlet port pressure, this pressure will be dissipated through passages 57 to the annular passage 58 and from thispas sage through other passages 57 to the 'pocketsinthe sealing section which have immediately before been in communication with the exhaust ports. The fluid pressure in the four pockets thus connected will be equalized when such pockets communicate with the next port, either an inlet or outlet port, the pressure differential between the fluid in the port and that in the-pocket will be just half of the pressure differential between the inlet and outlet ports. The shock of connecting regions containing fluid under diflerent pressures will thus-be reduced. By the reduction in shock consequent wear and noise will also be reduced and the life of the device will be prolonged. The pulsation of fluid discharged will also be materially lessened.

Fluid leaking into the space around the shaft 35 is conducted to the reservoir or tank of the hydraulic system through a drain connection 61, this connection communicating through an angular passage. 62 with a central opening 63 formed in end section 23, this central opening communicating with the chamber 26 through a central passage 64 and lateral passage 65 in the shaft 35, with the opening provided in section 22 for the bearings 34. The open outer end of this bearing-receiving opening is sealed by a shaft seal 66 which is held in place by a cap 67, this cap being secured tothe section 22 by screws 68. A spacing and sealing sleeve 70 is disposed between the bearing members 34 to separate the outlet port 28 from the portionof the opening-for the bearings 34' containing fluid at tank pressure. Suitable seals -71 are provided around the member 70 and cap-67 to prevent leakage. Other seals 72 are disposed between the

sections

22, 23 and 24 for a similar purpose. In the form of the invention shown, the end walls of the rotor chamber are lined with bronze or otherbearing mtaerial to provide a better bearing surface.

While the form of embodiment of the present invention as herein disclosed constitutes a preferred form, itis to be understood that other forms might be adopted, all coming within the scope of the claims which follow:

We claim: 1. A fluid pressure'energy translating device comprising a casing defining a rotor chamber having a" plurality of alternately arranged fluid transfer and sealing sectio'ns with peripheral wall surfaces spaced different distances from the axis of said chamber, said casing having inlet and exhaust ports communicating with said cham ber at opposite ends of said transfer sections; a rotor disposed for rotation in said chamber; vane elements spaced circumferentially around said rotor and movable radially therein to continuously engage said peripheral wall surfaces, adjacent vane elements cooperating with wall surfaces of said chamber to provide a plurality of pockets operative upon rotation of said rotor to transfer fluid from said inlet to said exhaust ports; and passage means in said casing establishing communication between all of said pockets disposed at points midway between the ends of each of said transfer and sealing sections as the rotor revolves, said rotor interrupting such communication immediately following the movement of said pockets beyond said midpoints.

2. A fluid pressure energy translating device comprising a casing defining a rotor chamber having a plurality of alternately arranged fluid transfer and sealing sections with va ne engaging peripheral wall surfaces spaced at different distances from the axis of said chamber, said casing having inlet ports communicating with said chamber at corresponding ends of said transfer sections and exhaust ports communicating with said chamber at the opposite ends of said transfer sections; intercommunicating passages formed in said casing, said passages terminating in pressure equalizing ports disposed in oom' munication with said chamber at the points disposed midway of the length of each of said transfer and sealing sections; a rotor disposed for rotation in said chamber; and vane elements spaced circumferentially around said rotor and movable radially'therein to continuously engage said peripheral wall surfaces, adjacent vane elements cooperating withthe vane engaging wall-surfaces of said chamber to form fluid receiving pockets operative to transfer flu-id from said inlet to said'exhau'st ports, each of said-pocketscommunicating with a pressure equalizing port as'it moves across the fluid transfer and-sealing sections, said equalizing ports being disposed to communicate with each of said pockets as the latter rotate past them and to be closed by said rotor as the pockets move beyond the midpoi-nts of said transfer and sealing sections.

.3.-A fluid pressure enerigy translating device comprising a c'asing'provided with a rotor chamber having spaced side walls and a vane-engaging peripheral wall with fluid-transfer and sealing-sections alternately ar= ranged and spaced different distances from theaxis of said chamber, said" casing having inlet ports communieating with the chamber at correspondingend's of said transtersections and exhaust ports communicating with said chamber at the other ends ofsalid transfer sections; a rotordisposed for rotation in said chamber, the sides of." said rotorhaving a bearing engagement with the adjacent w-allsof said rotor chamber, said adjacent chamber walls each being provided with leakage-collecting grooves entirely covered. by said rotor and being of different areas; passages extend-ing'transversely of said rotor to establish communication between grooves of different areas' on opposite sides of said chamber, and vane elements spaced circumferentially around said rotor and movable radially therein to continuously engage the peripheral wall of said chamber, adjacent vanes cooperating with said rotor and casing to form pockets operative to transfer fluid from said inlet to'said exhaust ports during rotation of said rotor.

4-; Av fluid pressure energy translating device compris ing a casing provided with a rotor chamber having spaced sidewalls and a vane-engaging peripheral wall with fluid transfer and sealing section's alternately arranged and spaced different distances from the axis of said chamber, said casing-having inlet ports" communicating with the chamber at corresponding ends of said transfer sections and exhaust ports communicating with said chamber at the other ends ofsaid transfer sections; a rotor disposed for rotation in said chamber, the sides of said rotor having a bearing engagement with the adjacent walls of said rotor chamber, said adjacent chamber walls each being provided with an outer circular leakage-collecting groove and an inner circular leakage-collecting groove having a greater area than the first-mentioned groove, both of said grooves being entirely covered by said rotor; passages extending transversely of said rotor to establish communication between the inner and outer grooves at opposite sides of said chamber, and vane elements spaced circumferentially around said rotor and movable radially therein to continuously engage the peripheral wall of said chamber, adjacent vanes cooperating with said rotor and casing to form pockets operative to transfer fluid from said inlet to said exhaust ports during rotation of said rotor.

5. A fluid pressure energy translating device comprising a casing provided with a rotor chamber having spaced side walls and a vane-engaging peripheral wall with fluid transfer and sealing sections alternately arranged and spaced diflerent distances from the axis of said chamber, said casing having inlet ports communicating with the chamber at corresponding ends of said transfer sections and exhaust ports communicating with the chamber at the other ends of said transfer sections; a rotor disposed for rotation in said chamber, said rotor being provided with radially extending transverse vane-receiving slots, the sides of said rotor having a bearing engagement with the adjacent side walls of said rotor chamber, said side walls being provided with concentric circular leakage-collecting'grooves of different areas, the radius of the largest diameter groove being less than the distance from the axis of said rotor to the inner ends of the vane slots therein; passages in said rotor to establish communication between grooves of difierent areas on opposite sides of said rotor chamber, and vane elements disposed for radial movement in the slots in said rotor to continuously engage the peripheral wall of said rotor chamber, adjacent vanes cooperating with said rotor and casing to form pockets operative to transfer fluid from said inlet to said exhaust ports during rotation of said rotor. t a

- 6. In a fluid pressure energy translating device, a casing having a rotor chamber and inlet and outlet ports; a rotor disposed for rotation in said chamber, portions of the periphery of said rotor being spaced from the adjacent casing wall to provide fluid pressure receiving sections,

the side walls of said rotor being in sliding engagement with the side walls of said chamber; vane elements disposed in said rotor for radial movement to continuously engage the walls of said rotor chamber, adjacent vane elements cooperating with said rotor and casing to provide pockets operative to transfer fluid between said inlet and outlet ports during rotation of said rotor; centering means for said rotor having a circular leakage-collecting groove at each side of said rotor between the periphery of said rotor and the axis thereof; a second circular leakage-collecting groove of greater area than the first-mentioned groove and between the same and the axis of said rotor, said grooves being entirely covered by said rotor; and passage means establishing communication between the outer groove on either side and the inner groove on the opposite side.

7. In a fluid pressure energy translating'device, a casing having a rotor chamber with inlet and outlet ports and a drain passage leading therefrom; a rotor disposed for rotation in said chamber, portions of the periphery of said rotor being spaced from the adjacent casing wall to provide fluid pressure receiving sections in communication with said inlet and outlet ports, the side walls of said rotor being in sliding engagement with the side walls of said chamber; vane elements disposed for radial movement in said rotor to continuously engage the peripheral wall of said rotor chamber and form pockets to transfer fluid from said inlet to said outlet ports during rotary movement of said rotor; fluid pressure centering means for said rotor having concentric leakage-collecting grooves at each side of said rotor between the periphery and the axis of rotation thereof entirely covered by said rotor, the inner-most groove having a greater area than the outer groove, passage means establishing communication between the outer groove on either side and the inner groove on the opposite side of said rotor; and additional passage means establishing limited communication between the inner-most groove and the drain passage leading from the 'r'otorchamber.

A fluid pressure energy translating device comprising a casing defining a rotor chamber having a plurality of alternately arranged fluid transfer and sealing sections with wall surfaces spaced different distances from the axis of said chamber, said casing having inlet and exhaust ports communicating with said chamber at opposite ends of said transfer sections; a rotor disposed for rotation in said chamber; vane elements spaced circumferentially around said rotor and movable radially therein, adjacentvane elements cooperating with wall surfaces of said chamber to provide pockets operative to transfer fluid from said inlet to said exhaust ports during rotary movement-of said rotor; port means in a side wall of said casing at points disposed midway of the length of each of said transfer and sealing sections and communieating with each of said pockets as the latter rotate past said port means; passage means establishing communication between all of said port means, said communicating port means serving to equalize the pressures in all of the pockets disposed midway of the length of the transfer and sealing sections as the rotor revolves, the said equalizing ports being disposed to beclosed by the rotor before the pockets communicate with the inlet and exh-aust ports.

References Cited in the file of this patent UNITED STATES PATENTS 711,239 Tree Oct. 14, 1902 1,737,942 Pagel Dec. 3, 1929 1,795,579 Storey Mar. 10, 1931 1,989,900 Vickers Feb. 5, 1935 2,256,459 Kendrick Sept..16, 1941 2,311,162 Du Bois Feb. 16, 1943 2,335,284 Kendrick Nov. 30, 1943 2,387,761 Kendrick Oct. 30, 1945 2,411,602 Tweedale Nov. 26, 1946 2,460,047 Von Wangenheim I an. 25, 1949 2,498,911 Chittenden Feb. 28, 1950 2,588,430 Svenson Mar. 11, 1952 2,626,570 Armington et al. Jan. 27, 1953 2,641,195 Ferris June 9, 1953 2,653,551 Rosain Sept. 29, 1953 FOREIGN PATENTS 243,388 Great Britain 1927 466,105 Germany 1947 594,441 Great Britain 1947