US2202911A - Pump - Google Patents

Description

June 4, 1940.

J. P. JOHNSON I 2,202,911

I PUMP Filed Jan. 6, 1938 2 Sheets-Sheet 1 Illll lIlHll I 3 zJg/ I m A in u ATTORNEY June 4, 1940. J. P. JOHNSON PUMP 2 Sheets-Sheet 2 I Filed Jan. 6, 1958 INVENTOR. JqMEs Plan/wow ATTORNEY.

Patented June 4, 1940- UNITED STATES PUMP a James P. Johnson, Shaker Heights, Ohio, assignor, by mesne assignments, to Pump Engineering Service Corporation, ration of Ohio Application January 6,

2 Claims.

This invention relates to rotary pumps and more particularly to pumps employing slidable vanes or blades and has for its primary object to provide a pump of the type referred to which is simple in construction, efficient in operation and inexpensive to manufacture.

Heretofore, in the production of pumps of the type referred to, it has been general practice to provide inlet and outlet passageways in the pump housing and where the latter is cast these passageways are usually cored out. Due to their location and shape it is difiicult to clean or machine these passageways with the result that such V operations are expensive and if not properly performed the pump mils to operate at its maximum efficiency. It is therefore, a further object of the present invention to eliminate the aforesaid objectionable features by providing a separable element on which such passageways are formed with ease and accuracy and subsequently mounting the element in the housing so that the passageways function in the manner intended.

A still further object of the invention is to 5 provide a separate rotor assembly which is of unitary arrangement and adapted to be subsequently mounted in the pump housing thereby eliminating the possibility of rotor misalignment or binding.

Another object of the present invention is to utilize the separable element on which the passageways are formed as an element of the rotor assembly unit thereby simplifying the construcion.

With the objects above indicated and other objects hereinafter explained in view my invention consists in the construction and combination of elements hereinafter described and claimed.

Referring to the drawings,

Figure 1 is a view in side elevation of a pump embodying the present invention.

Figure 2 is a. vertical sectional view taken on line 22 in Figure 1.

Figure 3 is a side elevational view of the stator and rotor unit showing the different elements in extended relation.

Figure 4 is a side elevational view of the stator 3 and rotor unit with the elements in assembled position.

Figure 5 is a front elevational view of one of the blades.

Figure 6 is a top plan view of that shown in 55 Figure 5.

Cleveland, Ohio, a corpo- 1938, Serial No. 183,639

Figure '7 is a top plan view of that shown in Figure 2.

Figure 8 is an end elevational view of that shown in Figure 2. t

Figure 9 is a developed view of the separable element shown in Figure 3 and illustrates the relationship of the passageways and by arrows the direction of flow of fluid.

Figure 10 is a vertical sectional view of a different construction of pump and showing a modification of the oil seal.

In the drawings I have illustrated a pump embodying the present invention designed particularly for use on aircraft, but it should be understood that the invention is adapted for other uses and is not therefore to be so restricted.

Referring more particularly to Figures 1 to 4 inclusive, the pump comprises a housing 20, preferably an aluminum casting, which has a body portion 2| of circular shape provided with an axial bore 22 extending inwardly from one end thereof and terminated by an end wall 23. The body portion 2| is provided with an inlet connection 24 interiorly screwthreaded and an outlet connection 25 also interiorly screwthreaded, which communicate respectively, by an inlet passageway 26 and an outlet passageway 21, with the interior of the bore 22 as more clearly shown in Figure 8. The body portion 21 has a laterally extending flange 28 adjacent its open end adapted to receive a cover member 29, which is also an aluminum casting, which extends across the open end of the body portion 2| and to which it is detachably connected by a plurality of bolts 30.

A packing ring 3|, preferably rubber, is disposed in a marginal groove 32 provided in the body portion 2| and is engaged by the cover member 29 when the latter is secured to place to provide a seal against the escape of the lubricant employed for lubricating the movable parts of the pump. The cover member 29 is provided with an inwardly extending circular flange 33 the outer peripheral surface of which slidably fits within the adjacent end of the bore 22. The inner side of the cover member 291s formed with a circular recess 34 to lighten the structure.

The stator and rotor assembly is made up as a unit and insertable within the bore 22 of the housing 20. This arrangement has two important objectives namely, that it simplifies the formation of the inlet and outlet passageways and by securing the rotor in the unit before assembly in the housing prevents rotor misalignment and binding. The stator and rotor unit, shown more clearly in Figure 3, comprises a sleeve 35, which may be a casting, and of a diameter to permit its being fit within the bore 22 as shown in Figure 2. The sleeve has an axial bore 36 and its outer peripheral surface is provided with non-communicating recessed portions constituting an inlet passageway 31 and an outlet passageway 38 shown more clearly in the developed view Figure 9. The sleeve 35 is provided with a pair of inlet and exhaust ports 39 and 40 respectively of substantially rectangular shape and which ports are spaced apart but in parallelism. The sleeve 35 is provided with a second pair of inlet and exhaust ports of identical shape and arrangement which are located diametrically opposite to the first pair of ports but in this case the relative position of the inlet and exhaust ports is reversed. It will be noted therefore, that the inlet and outlet passageways 31 and 38 extend angularly thus connecting their respective inlet and exhaust ports. When the sleeve 35 is properly positioned within the bore 22, the inlet passageway 26 communicates with the adjacent inlet port 39 and the outlet passageway 21 communicates with the adjacent exhaust port 40.

Cam members 4| and 42 are of identical formation and are disposed on opposite sides of the sleeve 35. These cam members have laterally extending flanges 43 which engage the adjacent ends of the sleeve and are detachably connected thereto by bolts 44, which in the present instance are located on diametrically opposite sides as shown in Figure 3. The cam members have portions 45 which extend into the bore 36 and axially aligned openings 46 for 'a purpose to be later described. One of the cam members, in this instance the cam member 42, may be provided with an opening in its outer face which aligns with a similar opening in the end wall 23 to receive a pin 41 for properly positioning the rotor assembly within the bore 22. The inner faces of the cam members 4| and 42 are identical except for their relative positions and each have two helical surfaces 48 and 49 which start from a segmental flat surface 50 and extend therefrom in opposite directions and terminate in a segmental fiat surface 5| identical with and diametrically opposite to the segmental surface 56 but lying indiflerent plains. The adjacent surfaces of the cam members 4| and 42 are ar ranged so as to be always in-parallelism and are maintained in this spaced relationship by the sleeve 35 and bolts 44. It will be noted that the helical surfaces 48 and 49 of the cam members, when assembled in the sleeve 35, extend angularly across the inlet and exhaust ports 39 and 40 producing substantially triangularly shaped ports as shown in Figure 4.

A rotor 52, of hardened steel, has a circum ferential extension 53 disposed concentrically within the sleeve 35 and is adapted for running engagement therewith. The extension 53 is also disposed between the cam members 4| and 42 and the opposite sides have running engagement with the segmental flat surfaces 5| thus separating the inlet and exhaust ports 39 and 40 so as to provide non-communicating chambers on opposite sides of the pump structure. The rotor has coaxial extensions 54 on opposite sides of the circumferential extension 53 which project into and are freely rotatable within the openings 46 in the cam members. The circumferential extension 53 has a plurality of radially disposed slots 53a, three of such slots being illustrated but any'desired number may be used depending upon the purpose intended. Blades 65 are slidably mounted in the slots 53a. and project beyond the sides of the circumferential extension 53 in such a manner that the opposite ends are in engagement with the adjacent surfaces of the cam members whereby upon rotation of the rotor the blades 55 are shifted laterally on opposite sides of the circumferential extension 53. The outer edges of the blades 55 have running engagement with the inner peripheral surface of the sleeve 35 and to reduce frictional resistance to a minimum the outer edges and opposite sides of the blades are suitably rounded. The rotor 52 has axially disposed stub shafts 56 and 51 formed integral therewith and by which the rotor may be rotatably mounted. The rotor is provided with a plurality of openings 58 which extend longitudinally thereof so as to lighten the structure and an axial opening 58' is provided so that the lubricant may pass therethrough to opposite sides of the pump for suitably lubricating the moving parts.

It will be noted that the cam members 4| and 42 and rotor 52 are first mounted in the sleeve 35 and when properly assembled the bolts 44 are screwed into place and the unit is complete. It is then inserted in the bore 22 and the cover member attached.

The stub shafts 56 and 51 are rotatably mounted in anti-friction bearings 59 and 60 secured in recesses provided in the end wall 23 and cover member 29 respectively. The cover member 29 has an integral axial extension 6| provided with a lateral flange 62 the outer surface of which is offset to provide a marginal recess 63 and attaching plate 64 has an opening 65 which enables the plate to be disposed in the recess 63. Bolts 66 detachably connect the plate 64 to the flange 62 and the plate is provided with additional openings by means of which the pump may be suitably connected. The extension 6| has an axial opening 61 which is enlarged at its inner portion to provide a shoulder 68. A bushing 69 is secured within the opening 61 and has a lateral flange 16 which abuts the shoulder 68. A sleeve H is rotatably mounted in the bushing 69 and has a lateral flange 12 which engages the adjacent end of the bushing 69 to form a seal against the escape of the lubricant. Pressure between the engaging portions of these members may be effected in any well known manner. In the present instance the clamping of the cover member to the body portion causes the inner race of the adjacent bearing to exert pressure against the inner end of the sleeve II to hold the flange 72 in contact with the end of the bushing 69. This sleeve H is provided with a square opening 13 which receives the squared end of the stub shaft 5'! for "rotation therewith. A plug 14 is received about midway in the opening 13 to close the same against the escape of the lubricant. The outer end of the opening is adapted to receive the end of a drive or driven means.

In Figure 10 a sectional view of a pump is illustrated wherein a modified form of seal is used. In this construction a coil spring 15 encircles a portion of the stub shaft 16 and has one end abutting the inner race of the antifriction bearing 11 and its opposite end abutting the adjacent end of the sleeve 18 so as to maintain the sleeve and bushing in sealing engagement. The structure of the pump shows the inlet and outlet passageways provided in the housing.

In the operation of the pump reference may be had to Figure 9 which illustrates diagrammatically a developed view of the outer surface of the sleeve 35 showing the relationship of the inlet and outlet passageways and their respective ports. Assuming that the rotor 52 is being driven in a clockwise direction as viewed in Figure 1, the blades 55 are carried therewith and as the opposite sides of the blades pass over the helical surfaces 48 and 49 of the cam members, the blades are moved laterally successively on one side of the circumferential extension 53 and in the same manner on the other side of the circumferential extension 53 diametrically opposite.

The action of the blades 55 during rotation of the rotor creates a vacuum in the inlet passageway 3'! which causes fluid to be drawn into the passageway through the inlet connection 24 and through the inlet ports 39 on diametrically opposite sides of the circumferential extension 53. A pressure is created in the outlet passageway 38 and the fluid is transferred by the blades to the exhaust ports 40, which likewise are located on diametrically opposite sides of the circumferential extension 53, through which it is discharged into the outlet passageway 38 and finally through the outlet connection 25 to the desired source. As the pressure exerted on the blades is the same on opposite sides of the circumferential extension 53 the rotor is at all times hydrostatically balanced thereby assuring a maximum of efficiency in its operation.

It will be understood, of course, that the device may be used as a motor, in which event, the rotor is connected to instrumentalities to be operated thereby. Under such circumstances fluid is introduced under pressure into the inlet or outlet connections, depending upon the desired direction of rotation of the rotor, passes through the inlet passageway 371 and inlet ports 39 on diametrically opposite sides of the circumferential extension 53. As the pressure of the fluid is the same on opposite sides of the blades the rotor is hydrostatically balanced at all times. The fluid after exerting its pressure upon the blades so as to rotate the rotor, is transferred to the exhaust ports 40 where it is discharged into the outlet passageway 38 and subsequently flows out through the outlet connection 25 where it can be again used.

While I have described the preferred embodiment of the invention it is to be understood that I am not to be limited thereto inasmuch as changes and modifications may be resorted to without departing from the spirit of the'invention as defined in the appended claims.

What is claimed is:

1. A hydraulic pump or motor comprising a.

housing having an axial bore extending inwardly from one end thereof and inlet and outlet openings for the admission and discharge of fluid, a cover member extending across-the open end of said housing and detachably connected to the latter, and a stator and rotor assembly insertable and removable as a unit into and from said bore and comprising a sleeve having non-communicating passageways formed on the outer peripheral surface, members positioned on the opposite ends of said sleeve and having annular portions projecting inwardly of the latter, the inner adjacent ends being spaced apart and provided with complementary cam faces, a rotor having a circumferential extension the outer peripheral surface of which has running engagement with the inner peripheral surface of said sleeve between the inner spaced ends of said annular portions, the opposite sides of said circumferential extension being in running engagement with portions of said cam faces, said circumferential extension having a plurality of radially disposed slots, blades slidably mounted in said slots and having their opposite ends projecting beyond the sides of said circumferential extension for engagement with the adjacent cam faces whereby, upon rotation of said rotor, said blades are moved laterally successively on one side of said circumferential extension and in the reverse direction diametrically opposite, said rotor being further provided with axially extending hub portions rotatably disposed in the annular portions of said members and axially extending projections rotatably mounted in said housing and cover member respectively, and means detachably connecting said members to the adjacent portions of said sleeve for maintaining'said rotor assembly in unitary relation.

2. A hydraulic pump or motor comprising a housing having an axial bore extending inwardly from one end thereof and inlet and outlet openings for the admission and discharge of fluid, a cover member extending across the open end of said housing and detachably connected to the latter, and a stator and rotor assembly insertable and removable as a unit into and from said bore and comprising a cast sleeve having non-communicating angularly disposed passageways formed upon the outer peripheral surface communicating at their opposite ends respectively with pairs of inlet and exhaust ports on diametrically opposite sides, one pair of ports being arranged in reverse relation with respect to the other pair of ports, members positioned on the opposite ends of said sleeve and having annular portions projecting inwardly of the latter, the inner adjacent ends being spaced apart and provided with complementary cam faces, a rotor having a circumferential extension the outer peripheral surface of which has running engagement with the inner peripheral surface of said sleeve between the inner spaced ends of said annular portions, the opposite sides of said circumferential extension being in running engagement with portions of said cam faces, said circumferential extension having a plurality of radially disposed slots, blades slidably mounted in said slots and having their opposite ends projecting beyond the sides of said circumferential extension for engagement with the adjacent cam faces whereby, upon rotation of said rotor, said blades are moved laterally successively on one side of said circumferential extension and in the reverse direction diametrically opposite, said rotor being further provided with axially extending hub portions rotatably disposed in the annular portions of said members and axially extending projections rotatably mounted in said housing and cover member respectively, and means detachably connecting said members to the adjacent portions of said sleeve for maintaining said rotor assembly in unitary relation.

JAMES P. JOHNSON.

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