US3041974A - Pumps - Google Patents

Description

July 3, 1962 E. R. JUDKINS PUMPS led May 25, 1956 United rates This invention relates to pumps and is particularly concerned with pumps of the pressure loaded type designed to operate in tandem and to be driven by a common driving means in a unitary assembly.

In previously employed pumping arrangements having two or more pumps arranged in a housing adapted to be commonly driven, it was necessary to manufacture and assemble, in eiect, two or more separate and complete pump units even though such units were enclosed in a unitary housing. These previously employed arrangements usually required at least two separate machining operations on the housing, as for example, when two pumps were assembled in one housing it was necessary to bore an axial chamber in one end of the housing for one pump and reverse the housing and axially bore a chamber in the other end for the second pump. These two separate chambers, though they may be inter-connected so that the common driving means may be disposed therein, obviously increased the cost of such pumps and still further, and equally as important, such pumps in many instances were found diicult to assemble and properly align, with resultant mal-functioning when in operation.

Accordingly, it is a primary object of my invention to provide a pumping assembly in a single housing and having more perfect alignment between two or more pumping units connected together in continuous driving relation.

A still further object of my present invention is to provide a pumping assembly containing multiple pumping units which housing can be manufactured economically by eliminating heretofore necessary machining steps such as end-to-end boring of the housing.

I propose to accomplish my invention by providing an assembly of pumping units which are disposed within a housing having a single continuous, uninterrupted, chamber or bore. I have found that effective results are realized when pump units of the form disclosed and claimed in the Roth et al. Patent No. 2,420,622, issued May 13, 1947, are disposed in the continuous uninterrupted, chamber or bore of the housing which forms an important aspect of my present invention and particularly effective results are obtained when pumps utilizing offset loading are disposed in the continuous, uninterrupted chamber or bore, which olfset loading is accomplished by the use of bushings or end plate bearing means such as disclosed in the co-pending Haberland Patent No. 2,823,615 and/or Compton Patent No. 2,824,522. Either type pumps utilizing concentrically loaded bushings or offset loaded bushings may be connected in my present invention in continuous driving relation by the common driving means disclosed in the Lauck Patent No. 2,665,637, issued January 12, 1954, and entitled Pumping System.

Accordingly, it is a still further object of my invention to provide a pumping assembly utilizing either concentric or olfset pressure loaded bushings or end plates connected together in continuous driving relation which pump units can be assembled in a common pumping chamber having the parts of each pump more perfectly aligned when connected in continuous driving relation so as to more properly function and to reduce wear and increase the life of each unit.

An ladditional object of my invention is a new and improved method of manufacture and assembly of multiple tnt pumping units which eliminates several machining steps by the boring or machining of a single continuous chamber into which the multiple pumping units are disposed.

The above, and other objects, advantages and uses of the present invention will become apparent from a reading of the specification and claims taken in connection with the appended drawing which forms a part thereof, and wherein:

FIGURE l is a sectional, elevational View of a pumping assembly constructed in accordance with the teachings of my invention and showing to advantage two separate pumping units having offset loaded bushings disposed in a housing which has a chamber, containing the two units, continuously and concentrically bored;

FIGURE 2 is a section through line 2-2 of FIGURE l showing to advantage the offset loading of the bushings employed in the assembly disclosed in FIGURE l;

FIGURE 3 is a fragmentary elevational section of a pump of the type disclosed in FIGURE 1 but showing an optional manner of forming the housing so as to eliminate a second cover member for the pump chamber;

FIGURE 4 is a fragmentary elevational section of a pump of the type disclosed in FIGURE 3 but showing the use of barrel type bushings; and

FIGURE 5 is a sectional view similar to FIGURE 2 but showing the use of concentric bushings in a pump of the type constructed in accordance with the teachings of my present invention.

Referring now to the drawings and in particular to FIGURES 1 and 2, there is shown a pumping assembly indicated in its entirety by 10 and comprising a housing 11 with a pair of cover members 12 and 13 suitably aiiixed to opposite ends of the housing by bolt means 14 and 15 (one each shown) and suitably sealed against leakage by conventional sealing rings 16 and 17 disposed in recesses 18 and 19 in the housing 11. Housing 11 has formed therein a pair of parallel, overlapping or intersecting, cylindrical chambers 20 and 21 forming a housing chamber. One side of said intersecting chambers or bores is iluidly connected by passage 22 with inlet passage 23 and the opposite side of said bores is placed in iluid communication with an outlet passage 24 by passage 25 formed in the housing.

Pressure loaded pump units, respectively designated in their entirety as pump P-1 and pump P-2, are disposed or received coaxially in said overlapping or intersecting cylindrical chambers Ztl and 21.

Pump P-l comprises a driven gear 26 and a driving gear 27 intermeshing with each other at the overlapping area of the cylindrical bores 20 and 21 as more clearlj,l shown in FIGURE 2. Gears 26 and 27 have hollow axially extending shafts 28 and 29 and are suitably journalled on the left-hand side, as shown in the drawing, in fixed bushings or end plate means 30 and 31 and on the right-hand side in axially movable, pressure loadable, bushings or end plate means 32 and 33. Axially movable bushings 32 and 33 are provided with radially extending forward surfaces or faces 34 and 35, respectively, which engage the radially extending gear side faces and, similarly, bushings or end plates 3i) and 31 are pro-vided with radially extending forward surfaces 36 and 37. All of the forward surfaces extend radially a distance equal to the outer periphery of the gear impellers 26 and 27 and form together with an adjacent portion of the housing chamber, a pumping cavity for pump P-l in the manner taught by the Roth et al. Patent No. 2,420,622. As explained in that patent, and as Will be further explained hereinafter, upon rotation of the driving gear 27 with concurrent rotation of the driven gear 26 fluid introduced in to the pumping cavity from inlet 23 will be discharged under pressure through outlet 24. A portion of the high pressure in the high pressure passage 24 is com- 3 municated t the rear of the axially movable bushings 32 and 33 to urge said bushings into sealing relationship with the gear side faces. In the embodiment shown, the means communicating the high pressure to the rear of the axially movable bushings 32 and 33 is passage 38 (FIGURE 2) formed in the housing 11.

Pump P-2 coaxially disposed in the housing chamber is similarly provided with intermeshing driving gear 39 and driven gear 40 having axially extending shafts 4l and 42, respectively, which are journalled on the left-hand side (as 4shown in FIGURE l) in axially movable, pressure loadable, bushings or end plates 43 and 44 and on the lefthand side in xed bushings or end plates 45' and 46. Bushings or end plates 43 and 44 are provided With forward radially extending surfaces or faces 47 and 4S engageable with the radially extending side faces on one side of the gears 39 and 40 respectively. Similarly, bushings 45 and 46 are provided with forward radially extending surfaces or faces 49 and 56 which engage the radially extending side faces on the opposite side of the gears. All forward faces are radially `co-extensive with the periphery of the gears and form together with a portion of the housing chamber the pumping cavity for pump P-Z. As explained in the Roth et al. patent No. 2,420,622, pressure admitted behind the axially movable bushings 43 and 44 urge these bushings axially toward the gear side faces to provide a pumping seal therewith. Pressure to urge said bushings toward the gear side faces is obtained from the `outlet pressure port 24 through passage 3S as explained in connection with pump P-l.

It is important to note that both pumps, P-ll and P-Z, are substantially contained within the housing chamber formed by the adjoining cylindrical bores 2l? and 21 which as shown in FIGURE 1 Aare bored completely through housing 11. Cover 12, on the left-hand side of the assembly is provided with a pair of bores 51 Vand 52 of a diameter less than the diameter of the bores and 21 to accommodate the reduced tubular end portions or Shanks 53 and 54 of iixed bushings k36 and 31, respectively, and similarly, cover 13 on the right-hand side of the assembly is provided with a pair of bores 55 and S6 to accommodate the reduced tubular end portions or shanks S7 and 58 of fixed bushings 45 and 46 respectively. The driving gears 27 and 46 of pumps P-1 and P-2, respectively, are commonly driven, in the embodiment shown by a shear section coupling of the type described and claimed in the Lauck Patent No. 2,665,637, issued January 12, 1954, and there is provided shearing sections 59 and 60 to accommodate the seizure of either of pumps pumps P-l and P-2 in a manner taught in said patent. In practice, this coupling can be easily attached to another pump or pumps so as to have three or more `such pumps operating in tandem, if desired. Shaft 61, nternally received in and drivingly connected to hollow shafts 29 and 42 of driving gears 27 and 46, respectively, is externally splined at its left end, as indicated at 62, in FIG- URE l to accommodate the internal splines of shaft 29 and to be connected thereto and further extends through a suitable bore 63 in cover 12 which connects with bore 52 and forms a continuation thereof to accommodate a suitable driving means (not shown). Shaft 6l is also splined at its right end, as indicated at 64, to accommodate the internal splines of shaft 42 to provide a suitable driving arrangement. Since this arrangement is explained in the aforesaid Lauck Patent No. 2,665,637, no further detailed explanation is deemed necessary herein.

Of particular importance in my present invention is the arrangement of the two pumps P-l and P-2, so that the respective bushings or end plates form the pumping cavity of each pump and at the same time easily accommodate the principle of offset loading of the axially movable end plates.

Referring now in particular to bushings 32 and 43 of the driven gears 26 and 39 of pumps P-1 and P-2, respectively, it can be seen that there is an axially extending tubular portion or shank 65 and 66 on the respective bearings 32 and 43 which forms a radially extending back surface 67 and 68 on each bushing oppositely facing the forward faces 34 and 47 respectively. The outer periphery of the shank 65 is circular, as indicated at 69 and more clearly shown in FIGURE 2, but formed in such a manner that its center is offset toward the inlet port 23. The shank 66 of bushing 43 is similarly formed symmetrically to the shank 65. It is to be noted that in so disposing shank 65, the rearward motive surface area 67 is defined in such a manner that it has a major area and a minor area, the major area being located near the outlet of the pump and the minor area being located near the inlet of the pump. Differently expressed, the area of rear or motive surface 67 has a substantially circular inner periphery 69 eccentrically located with respect to the axis of rotation of the gears and a substantially circular outer periphery 76 concentrically located with respect to the axis of the gears, which geometric configuration of motive surface 67 is accomplished by the eccentric disposition of shank 65. Motive surface 68 on axially movable bushing 43 is similarly formed to have a major and minor area with its major area near the outlet and its minor area near the inlet by the disposition of shank 66 as explained in connection with bushing 32.

In order to prevent leakage of pressure directed to these eccentric surfaces 67 and 68 and to properly form` a pressure loaded chamber behind the axially movable bushings 32 and 43, there is provided a circular ring member 71, preferably of steel, of less cross-sectional thickness than the minimum radial extension of the rear surfaces- 67 and 68 and disposed around the respective Shanks 652 and 66. The inner peripheral edges of the ring 71 are recessed, as at 72 and 73, to contain O- ringr seals 74 and 75, respectively, which when assembled form together with the Shanks 65 and 66 a sealing relationship therewith. The steel ring 7l is also properly proportioned to have a lesser width than the distance between the back surfaces 67 and 68 when the Aaxially movable bushings 32 and 43 are in their extreme fully sealed, fully loaded position against the gear side faces so as to provide a proper clearance between the ring and the back surfaces 67 and 68 to permit axial movement of the bushings. It can be seen that the adjacent portion of the housing chamber forms together with the back surfaces 67 and 68 a pressure loading chamber 76, and leakage of high pressure from that chamber is prevented by the O- ring seals 74 and 75. A similar ring 77 with similar recesses 78 and 79 and O- ring seals 80 and 81 are disposed about the eccentric tubular portions or Shanks 82 and 83 of axially movable bushings 33 and 44 respectively. As explained in connection with eccentric back faces 67 and 68 of axially movable bushings 32 and 43, the shanks 82 and 83 form radially extending eccentric back faces 84 and on axially movable bushings 33 and 44 and these faces form together with the adjacent portion of the housing 11 a pressure loading chamber 86 behind the bushings journalling the driving gears 37 and 40. The two pressure loading chambers 76 and 86 are in pressure communication wit-h each other. As clearly shown in FIGURE 2, the effective surface area of back surface 84 is offset loaded in a manner similar to that shown with respect to back surface area 67 of axially movable bushing 32. The effective surface area of back surface 85 is symmetric to back surface 84 as is apparent.

As explained in the Roth et al. Patent No. 2,420,622, the Haberland Patent No. 2,823,615 and the Compton Patent No. 2,824,522, above mentioned, by application of pressure on the rear or motive surfaces 67, 68, 84 and 85 as eccentrically dened, the forces acting upon such surfaces overcome the pressure gradient in the pumping cavities of the respective pumps.

As further explained in the Roth et al. Patent No. 2,420,622, it is usually necessary to provide initial pressure loaded springs, such as those indicated in their entirety as 87, which are seated in axial recess 88 formed in the terminal end portions of shanks 65 and 82 of axially movable bushings 32 and 33 and at their other ends in recesses 89 formed in the oppositely facing terminal end portions of shanks 66 and S3 of bushings 39 and 44 and under slight compression so as to urge the respective bushings in opposite directions toward their respective gear side faces.

The chambers, commonly called the seal chambers which are sealed off from the pressure loading chamber formed by high pressure chambers 76 and 86 in the area of the shank terminal end portions of the axially movable bushings and indicated in drawings as 90 and 91 are vented to `a pressure less than discharge pressure, usually through a one-way valve as explained in the Roth et al. Patent and proper operation of the pump. No further detailed explanation of this is deemed necessary herein except to explain that this venting, in the embodiment shown, is accomplished through the hollow driving and driven shafts, through passage 90 formed in the cover I2 and thence to sump.

Turning now to FIGURE 3, there is shown a pump substantially the same as the pump disclosed and explained in connection with FIGURES l and 2 except that the housing is formed so as to eliminate the cover member 13. In this maner the housing, indicated in this FIGURE as lla contains counter-bores (one shown as 55a) such as shown in cover member 13 in FIGURE l to accommodate the bushings (one shown as 45a). All other parts in the pump are similar to the parts shown in FIGURE l and have been correspondingly numbered with the suffix a to identify such parts. Obviously, the pump manufactured in accordance with the teachings of this figure has many advantages in its manufacture and operates as advantageously as the pump disclosed in FIG- URE 1.

In FIGURE 4 there is shown a pump utilizing barrel type bushings, one shown and indicated as 45h, and contained in `a housing 11b constructed in .accordance with the general teachings of FIGURE 3. Similar parts in this gure are also designated by the same numbers with addition of the suffix b. Obviously, a pump having barrel type bushings such as those disclosed in FIGURE 4 could be manufactured with a cover member such as 13 in FIG- URE l, if desired.

FIGURE 4 is substantially the same as FIGURE 2 and contains correspondingly numbered parts with the sufiix c except it is to be noted that the shank or tubular portions of the bushings are concentric to the axis of rotation of the gears.

Pumps such as disclosed in FIGURES 3, 4 and 5 operate in exactly the same manner as that explained in connection with FIGURES l and 2. It is also to be pointed Out in connection with FIGURE 5 that the housing containing concentric bushings can be identical with the housing containing the offset loaded bushings and this forms an important aspect of my invention.

Having thus described my invention in detail, I would like further to point out that I have accomplished an expeditious manner of manufacturing pump assemblies. The simple step of placing a housing member, such as 11, in a jig and boring it throughout, as in the case of the pump shown in FIGURE l, or blind boring and counterboring the housing as shown in FIGURES 3 and 4 forms a chamber for two separate and distinct pumps without the necessity of moving the housing from its initial position so as to bore and counter-bore the opposite end of the housing for a second pump. Both pumps P-l and P-2 can be placed in this single continuously bored housing chamber.

While I have disclosed my invention in connection with certain specific embodiments thereof, it is to be understood that these are by Way of example rather than limitation, and it is intended that the invention be defined by the appended claims which should be given a scope las broad as consistent with the prior art.

I claim:

l. An intermeshing gear type pump assembly including means defining an enclosing housing having a pair of intersecting chambers formed therein, a first gear pump unit, a second gear pump unit, both said pump units being disposed in said chambers and being axially spaced from each other, means connecting said pump units in continuous driving relation, gear impellers for each unit having axially extending journals and intermeshing at the juncture of said chambers, pairs of bushings surrounding said journals and providing each gear pump unit with a pump cavity therein, means defining inlet means and outlet means in said housing communicating respectively with `said cavities, at least one pair of said bushings of each unit being axially movable, each pair of said movable bushings being disposed between said first gear pump unit and said second gear pump unit and having inner faces forming the end walls of each said pump cavity and 'adapted to make endwise sealing contact with the sides of said impeller, each said pair of movable bushings having opposed outer faces, axially -spaced from each other, sealing means in contact with each of said movable bushings forming with said outer faces and said enclosing housing a pair of intersecting, substantially annular, pressure chambers, and fluid passage means affording communication between said pressure chambers and said outlet means whereby said movable bushings are forced into endwise sealing contact with the sides of said. impellers.

2. An -intermeshing gear type pump assembly including means defining an enclosing housing having a pair of intersecting chambers formed therein, a first gear pump unit, a second gear pump unit, both said pump units being 'disposed in said chambers and being axially spaced from each other, means connecting said pump units in continuous driving relation, gear impellers for each unit having axially extending journals and intermeshing at the juncture of said chambers, pairs of bushings surrounding said journals and providing each gear pump unit with a pump cavity therein, means defining inlet means and outlet means `in said housing communicating respectively with said cavities, at least one pair of said bushings of each unit being axially movable, each said pair of movable bushings being disposed lbetween said first gear pump unit and said second gear pump unit and having inner faces forming the end walls of each said pump cavity and adapted to make endwise sealing contact with the sides of said impeller, each of said movable bushings having opposed outer faces axially spaced from each other, sealing means in contact with each of said movable bushings forming with said opposed faces and said enclosing housing a pair of intersecting, substantially annular, pressure chambers, said pressure chambers being eccentrically oriented with respect to the axes of the journals and fluid passage means affording communication between said pressure chambers and said outlet means whereby said movable bushings are forced into endwise sealing contact -with the sides of said impellers.

3. An intermeshing gear type pump assembly including means defining an enclosing housing having a pair of intersecting chambers formed therein, a first gear pump unit, a second gear pump unit, both said pump units being disposed in said chambers and being axially spaced from each other, means connecting said pump units in continuous driving relation, gear impellers for each unit having axially extending journals and intermeshing at the juncture of said chambers, pairs of bushings surrounding each said journal and providing each gear pump unit with a pump cavity therein, means defining uid inlet means and fluid outlet means in said housing communicating respectively with said cavities, at least one pair of said bushings of each unit being axially movable, each pair of said movable bushings being disposed between said first gear pump unit and said second gear pump unit and having inner faces forming the end walls of each said pump cavity and adapted to make endwise sealing contact with the sides of said impeller, each of said movable bushings having a shank portion providing a substantially annular recessed area adjacent the enclosing housing, and a ring member in sealing engagement with the shank portion of adjacent, axially spaced movable bushings forming with said movable bushings and said enclosing housing a pair of intersecting, substantially annular, pressure chambers, and fluid passage means aiording communication between said pressure chambers and said outlet means whereby said movable bushings are forced into endwise sealing contact with the sides of said impellers.

4. An intermeshing gear type pump .assembly including means defining an enclosing housing having a pair of in- .tersecting chambers formed therein, a first gear pump unit, a second gear pump unit, both said pump units being disposed in said chambers and being axially spaced from each other, means connecting said pump units in con- .tinuous driving relation, gear impellers for each unit having axially extending` journals and intermeshing at the juncture of said chambers, pairs of bushings surrounding each said journal and providing each gear pump unit with a pump cavity therein, means defining fluid inlet means and uid outlet means in said housing communicating respectively with said cavities, at least one pair of said bushings of each unit being axially movable, each pair of said movable bushings being disposed between said rst gear pump unit `and said second gear pump unit and having inner faces forming the end walls of each said pump cavity and adapted to make endwise sealing contact with the sides of said impeller, each of `said movable bushings having a shank portion of reduced diameter providing a substantially annular recessed area adjacent 8 said enclosing housing, a ring member in sealing engagement with the shank portions of adjacent, axially spaced movable bushings forming with said movable bushings and -said enclosing housing a pair `of intersecting, substantially annular, pressure chambers, said pressure chambers being eccentrically oriented with respect to the axes of said journals and uid passage means affording communication between said pressure chambers and said outlet means whereby said movable ybushings are forced into endwise sealing contact with the sides of said impellers.

References Cited in the iile of this patent UNITED STATES PATENTS 672,970 Westinghouse Apr. 30, 1901 2,009,137 Kleckner July 23, 1935 2,312,886 Ellinwood Mar. 2, 1943 2,373,457 Chisholm Apr. 10, 1945 2,382,042 Etnyre Aug. 14, 1945 2,412,588 Lauck Dec. 17, 1946 2,420,622 Roth et al. May 13, 1947 2,490,115 Clarke Dec. 6, 1949 2,584,865 Gordinier Feb. 5, 1952 2,649,740 Murray et al. Aug. 25, 1953 2,665,638 Lauck Ian. l2, 1954 2,695,566 Compton Nov. 30, 1954 2,714,857 Albright et al Aug. 9, 1955 2,726,604 Aspelin et al Dec. 13, 1955 2,751,846 Lapsley June 26, 1956 2,765,749 Mosbacher Oct. 9, 1956 FOREIGN PATENTS 716,036 Germany Jan. 12, 1942 900,188 France Sept. 18, 1944

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