US2998827A - Valve construction for fluid pressure pump and the like - Google Patents

Description

p 1961 E. E. COOK ETAL 2,998,827

VALVE CONSTRUCTION FOR FLUID PRESSURE PUMP AND THE LIKE Filed April 14, 1958 2 Sheets-Sheet 1 INVENTORS ERNEST E. COOK HARRY J. \SADLER ATTORNEYS Sept. 5, 1961 E. E. COOK ETAL 2,998,827

VALVE CONSTRUCTION FOR FLUID PRESSURE PUMP AND THE LIKE 2 Sheets-Sheet 2 Filed April 14,. 1958 m GhR 1NVENTOR ERNEST E. COOK HARRY a. SADLER A T TORNEYS States Patent 2,998,827 VALVE CONSTRUCTION FOR FLUID PRESSURE PUMP AND THE LIKE Ernest E. Cook and Harry J. Sadler, both Hypro Engmeering 00., 700 39th Ave. NE., Minneapolis, Minn. Filed Apr. 14, 1958, Ser. No. 728,315 2 Claims. (Cl. '137--543.13)

Our invention relatesgenerally to fluid pressure devices such as pumps, motors and the like, and more par ticularly to improvements in valves for such devices.

An important object of our invention is the provision of a novel check valve for fluid pressure devices and involving a valve seat element and a valve element, either or both of which may be quickly and easily removed from the valve body for replacement, andas easily replaced.

Another object of our invention is the provision of a check valve structure including a valve seat of nonmetallic material, and of novel means for supporting the valve seat against movement or displacement in the valve body due to flow of fluid through the valve and the pressure of said fluid. I

I Another object of our inventionis the provision of check valve structure as set forth including a valve element and novel means mounting said valve element for movements toward and away from the valve seat. Still another object of our invention is the provision of novel valve element mounting means including a resilient member which may be flexed and snapped into place in the valve body and held against accidental movement therein.

' Another object of our invention is the provision of check valve structure as set forth which is simple and inexpensive to manufacture, which is highly eiiicient in operation, and which is rugged in construction and durable in use. 1

The above, and still further highly important objects and advantages of our invention, will becomeapparent from the following detailed specification, appended claims, and attached drawings. Y

' Referring to the drawings, which illustrate the invention, and in which like reference characters indicate like parts throughout the several views:

FIG. 1 is a view in axial section of a wobble plate operated piston pump made in accordance with our invention;

FIG. 2 is a transverse section taken substantially on the line 2--2 of FIG. 1;

FIG. 3 is an enlarged detail corresponding to a portion of FIG. 1;

FIG. 4 is a fragmentary section taken on the irregular line 4-4 of FIG. 3; and

FIG. 5 is a view in plan of a valve element supporting member of our invention.

Referring with greater detail to the drawings, the numeral 1 indicates a main body or cylinder block having a flange 2 at its inner end, and defining a central opening 3 extending therethrough and a plurality of circumferentially spaced pump cylinders 4 parallel to the central opening 3. An end cap 5 is-bolted or otherwise rigidly secured to the outer end of the cylinder'block 1, and defines therewith a chamber 6 for reception of lubricant, not shown, which lubricant may be added through a screw threaded opening 7 that is normally closed by a threaded plug or the like 8. The end wall of the cap 5 defines a central opening that is closed by a window 9 of suitable transparent material such as glass or transparent synthetic plastic material. By means of the window 9, the operator may observe the level of lubricant within the chamber 6 at all times. i r

The inner flanged end of the cylinder block or main body 1 defines an annular recess Itlconcentric with the Patented Sept. 5, 1961 2 central opening 3 and into which the inner ends of'the cylinders 4 open. An annular valve plate 11 is-seated in the recess 10 and is provided with a plurality of circumferentially spaced pairs of inlet and outlet passages 12 and 13 respectively. The inlet passages 12 are normally closed by spring biased inlet check valves 14, Whereas the outlet passages 13 are normally closed by similar spring biased check valves 15. Each pair of inlet and outlet passages 12 and 13 respectively is in direct communication with a different one of the cylinders 4 through respective check valves 14 and 15. The annular valve plate 11 is held securely in place within the recess 10 by an annular manifold that is anchored to the adjacent end of the main body 1 by a plurality of circumferentially spaced screws or bolts 17 screw-threaded into suitable threaded apertures in the flange 2 of the main body 1. The central portion of the annular manifold 16 is releasably anchored to the cylinder block or-main body 1 by a tubular anchoring screw 18 that is screw-threaded into a reduced diameter threaded end portion of the central opening 3 of the cylinder block 1, as indicated at 19. The annular manifold 16 defines concentric outer and inner manifold chambers 20 and 21 respectively, the former of which communicates with an inlet 22 and all of the inlet passages 12, and the latter of which communicates with an outlet 23 and all of the outlet passages 13. The cylinder block engaging face of the annular valve plate 11 is provided with a plurality of annular grooves 24, each of which surrounds a difi'erent pair of the passages 13 and 14, and each of which contains a different sealing ring 25, the sealing rings 25 engaging the bottom of the annular recess 10 to seal each cylinder 4 from the others thereof. The annular manifold 16 is provided with concentric inner, intermediate and outer axially opening annular grooves 26, 27 and 28 respectively, which contain annular sealing rings 29, 30 and 31, which have sealing engagement with the flat surface of the adjacent end of the annular valve plate 11 to prevent leakage of fluid between the manifold chambers 20 and 21 and from either thereof to atmosphere. The manifold 18 defines an opening 32 between the inlet and outlet chambers 20 and 21 respectively, in which opening is seated a pressure relief valve indicated in its entirety at 33. The valve 33 comprises a'tubular valve body 34, the lower end of which defines a passage 35 communicating with the inlet and outlet. manifold chambers, the valve body being screw-threaded into a portion 36 of the manifold 16, as indicated at 37, see FIG. 1. The relief passage 35 is normally closed by a ball valve element 38 that is yieldingly urged towardthe adjacent end of the passage 35 by a coil compression spring 39 contained within an adjustment screw 40 screw; threaded into the upper end portion of the valve body 34. The adjustment screw 40 is held against accidental movement by a conventional lock nut 41. V

The cylinders 4 are each counterbored from their outer ends to provide diametrically enlarged portions or recesses 42 for the reception of annularfholders or mounting sleeves 43 and'guide sleeves 44. Each-mounting sleeve 43 is provided with axially inner and outer sealing rings 45 and 46 respectively, of conventional structure, each thereof being located adjacent an opposite end of each mounting sleeve. Each mounting sleeve 43 is further provided, intermediate the rings 45 and 46, with a sealing ring 47, which, like the rings 25, 29, 30 and 31 is in the nature of a conventional 0 ring. Intermediate the inner sealing ring 45 and the 0 ring 47, each mounting sleeve 43 is formed to provide inner and outer circumferential channels 48 and 49 respectively, and circumferentially spaced connecting passages 50. The cylinder block or main body 1 is drilled to provide a plurality of breather Q passages 51, one of which is shown in FIGURE 1, there being one for each of the cylinders 4. Each passage 51 communicates at one end with a different one of the outer channels 59, and at its inner end with a different one of a plurality of cooperating passages 52 extendingthrough the annular valve-plate llwhereby to communicate with the inlet manifold chamber 20. As shown in FIG. 2, the valve plate 11 is provided with a plurality of annular grooves concentric with each passage 52 for the reception of small rings 53 that have sealing engagement with the adjacent end of the cylinder block 1. The mounting sleeves 43 are held in position at the bottom of their respective recesses 42 by their respective guide sleeves 44 and snap rings. 54 suitably mounted in grooves in the. outer end portionsof each recess 42 andengaging the outer end portions of the guide sleeves 44.

The mounting sleeves 43 and guide sleeves 44 define cylinder extension portions 55 of slightly smaller diameterthan the cylinders4 betweenthe recesses 42 andthe valve equipped inner end of the cylinder block 1, each of the cylinder extension portions 55 snugly slidably receiving a different one of a plurality of elongated pistons 56.the inner ends 57 of which are adapted to move freely between the inner ends of the cylinders 4 and the bottoms of? the recesses 42. At their outer ends, the pistons 56 areformed to provide extended portions-58 that project outwardly into the chamber 6, see FIGURE 1. The outer end portions 58 of the pistons 56 are providedwith rigid pistonpins 59 that extend radially inwardly toward the axis of the central opening 3 of the cylinder block 1. The

piston pins 59 extend inwardly through transverse aper-.

tures in wrist pins 60 that, are mounted for rotary and axial sliding movements in circumferentially spaced portions of awobble plate 61, the piston pins 59 being capable of rotary and axial sliding movements in the transverse apertures of their respective wrist pins 60.

A drive shaft 62 extendsaxially of the central opening Sand is journalled therein by means of anti-friction bearings 63 and 64. The end portion of the drive shaft 62 isprovided with an axial recess 65 for reception of the diametrically reduced portion 66 of a coupling element 67. An anchoring bolt 68 extends axially through a central aperture in the reduced portion 66 and has screwthreaded engagement with the drive shaft 62 to hold the coupling element 67 against axial movement with respect to the drive shaft 62. The inner end of the drive shaft 62 is provided with a plurality of circumferentially spaced teeth;69 between an adjacent pair of which extends a shear pin70 that is mounted in a longitudinally extended opening 71 in the coupling element 67. As shown in FIG. 1, the outer end of the coupling element 67 is recessed to receive a motor shaft, not shown, and is provided with a key 72 and a ball detent 73 for engagement with a suitable key and notch respectively in the motor shaft, not shown, the ball detent being releasably locked in place by a spring pressed locking sleeve 74 mounted on the outer end portion of the coupling element 67 for limited axial movements relative thereto. A conventional annular sealing element 75 closely encompasses the inner end portion of the drive shaft 62 between the anti-friction bearings 64 and the tubular anchoring screw 18 to prevent escape of lubricant fromthe chamber 6, and central opening 3.

The outer end of the drive shaft 62 projects into the chamber 6 and is there provided with an integrally formed oblique crank portion 76 which journals the wobble plate 61, by means of an anti-friction bearing 77. As the drive shaft 62 rotates, the crank portion 76 thereof imparts wobbling movement to the wobble plate 61 to cause axial reciprocatory movement to be imparted to the several pistons 56. As each piston 56 is moxed axially outwardly away from the inner end oftherespective cylinder 4, its respective check valve 14 is opened to permit flow of fluid into the cylinder 4 from the low pressure manifold passage 20, the cooperating. check, valve being closed. Then, as each piston 61 moves axially 4 inwardly, the-checkvalve 14 thereof closes and, the check valve 15 thereof opens to permit fluid to flow outwardly from the cylinder 4 to the high pressure passage or manifold chamber 21 and from thence outwardly through the outlet 23.

Inasmuch as, the pump above described is utilized to deliver fluid at high pressures, arelatively small portion of the fluid might, at some timeor other escape between the pistons 56and their. cooperating sealing rings 45 to their respective inner channels 48 during the pressure stroke of each piston 56. The channels 48 and 49, together with their; connecting passagesxSl) communicating with therelatively low pressure. iuletmanifold passage orchamber 20, fluidescaping outwardly past the sealing rings 45 isdelivered back, to the low pressure sideof the pump. The sealing.rlngs,46 areeliectivegtopreventlubri: cant from escaping fromthe chamber 6 to the fluidre: turn channels 48,,.due,to thefact that the pressure Within the chamber 6 issubstantially atmospheric. 47 betweenthe channels 48 and the sealing rings 46 provide an effective seal against the fluid, inthe channels 48 from escaping tothe chamber 6.

The several check valvesinthe valve platelhiudicated in their entirety atl and15 and now to be described in detail, are identical in structure, the valve 14 differing from the valve 15 only as to arrangement in the valve platell. The valve 14, opens to, permit fluidto be drawn from the low pressure manifold chamber 20 to the cylinders 4, while the check valves1 5 opento permit fluid to be moved from the cylinders, 4 to the outlet or high pressure manifold chamber 21 uponaxial movement of the piston 56 toward the valve plate '11. The passages 12 and 13111 the valve plate 11 are; also identical, each thereof having a diametrically largepassage portion78 and .a diametrically smaller or reduced. passage portion 79., said portions cooperating to define annular shoulders 80. The shoulders 30 of the passages12 face their respective cylinders 4, while the shoulders 80 of the passages 13 face in the direction of the highpressure passage or manifold chamber 21. Each larger diameter passage portion 78 contains au.annular washer-like valveseat element 81having one side seated against its respective shoulder 80. The valve seat elements 81 are preferably non-metallic and may be made from any suitable materialsuch as synthetic plastics, preferably of the type known as Teflon." This material, being somewhat flexible and resilient, the seat elements 81 must be securely held against the shoulders 80 so that the flow of fluids through the passages 12 and 13 do not cause the same to be uuseated, from their, respective shoulders 80. For the purpose of releasably lockingthe seat elements 81 against movement away fromtheir respective shoulders 80, we provide annular retaining elements or rings 82 which are mounted in the large diameter passage portions 7 8, and snap rings 83 that are seated in annular grooves 34 in the cylindrical side walls of the passage portions 78. As shown in FIG. 3, the retainer rings 82 engage the sides of the seat element 81 opposite the shoulders 80, thesnap rings 84 being disposed with respect to their shoulders 80 to hold the retainer rings 82 against their respective seat elements 81. The retainer rings 82 are preferably metallic, and have inner diameters greater than the inner diameters of the seat elements 81, and beveled outer faces 35 for a purpose which will hereinafter become apparent.

The valves 14 and 15 further include valve elements 86 having circumferentially spaced radially outwardly projecting lugs 87 which slidably engage thecylindrical walls of their respective enlarged passage portions 78 during movement of the valve elements 86 toward and away from their respective valve seat elements 81. Each valve element 86 is provided with an axially extcndingguidepin 88 that is axially slidably received in the central aperture 89 of a mounting member 90. As best shown. in FIGS. 3 and 5, themounting members or arms 90-are provided attheir opposite ends with circumfereutially-extending feet 91 and 92 that are adapted to be received The 0 rings:

in diametrically opposite portions of radially inwardly opening channel 93 in the larger diameter passage portion 78. The arms 90 are preferably made from synthetic plastic material and have embedded therein reinforcing rods 94 of resilient wire stock or the like. With the valve element mounting arms 90, being of greater length than the diameter of the larger passage portions 78, the same are bent or flexed to enable the enlarged feet 91 and 92 to be received in their respective channels 93. When the feet 91 and 92 are thus received in the channels 93, the resilience of the arms 90 and their reinforcing wires 94 causes the arms 98 to assume their normal straight positions, shown best in FIGURE 3. In View of the fact that the inwardly opening channels 93 are disposed in closely spaced relation to the adjacent inner and outer surfaces of the valve plate 11, it is important that the arms 90 be held against rotation relative to the valve plate 11, which rotation of the arms 90 would produce wear on the feet 91 and 92 and the valve plate 11, 11M- mately causing displacement of the arms 90. For the purpose of anchoring the arms 90 against such rotation on the axes of the passages 12 and 13, the valve plate 11 is drilled to provide notches 95 in the channels or recesses 93. The enlarged feet 92 of the arms 90 are each provided with a radially outwardly projecting tooth 96 which is received in a respective notch 95 to eifectively lock the arm 90 against rotary movement.

Each of the valves 14 and 15 is provided with a coil compression spring 97 that is interposed between the arm 90 and valve element 86 and which yieldingly urges its respective valve element 86 toward seating engagement with its respective seat element 81. Preferably, and as shown, each valve element 86 is substantially in the form of a truncated hemisphere, the smaller inner end portion thereof being adapted to pass freely through its respective beveled retainer ring 82 to make seating engagement with its respective seat element 81, as shown in FIG. 3. The beveling of the retainer rings 82 permits the rings to be of sufiicient axial thickness to render the same of a rigidity sufiicient to hold the seat elements 81 in position under all operating conditions. Further, the beveled surface 85 and the larger inner diameter of the retainer rings 82 allow the valve elements 86 to make eificient seating engagement with their respective seat elements 81, and without interfering with free movement of the valve elements 86 between their open and closed positions.

When it is desired to replace any one or more of the Valve elements 86 or seat elements 81, it is only necessary that the coupling element 67 and manifold 16 be removed from the adjacent end of the cylinder block 1, thus permitting the valve plate 11 to be withdrawn from the recess 10, after which any one of the valve element mounting arms 90 may be bent suificiently to enable the same to be removed from its respective recess. It will be appreciated that the yielding bias exerted by any one of the coil springs 97 is not suficient to flex or bend its respective arm 90. When a given arm 90 has been bent sufficiently to enable the same to be withdrawn from its respective recess 93, removal of the valve element 86 I thereof and other parts associated therewith, is an easy matter.

The above described pump together with the novel check valve structure contained therein has been thoroughly tested and found to be completely satisfactory for the accomplishment of the objectives set forth; and while we have shown and described a preferred embodiment of our novel structure, it will be understood that the same is capable of modification, and that modification may be made without departure from the spirit and scope of the invention as defined in the claims.

What we claim is:

1. In a check valve for fluid pressure devices, means defining a fluid passage having a large diameter portion and a smaller diameter portion, said passage'portions defining inner and outer edges of an annular shoulder, a flexible annular valve seat element of non-metallic material seated on said shoulder, a rigid annular metallic retainer element in said larger diameter passage portion abutting said seat element, said larger diameter passage portion defining an annular radially inwardly opening recess in axially spaced relation to said shoulder and a radially inwardly opening circumferential groove intermediate said shoulder and said recess, a snap ring in said groove and engaging said retainer element to releasably lock said retainer and seat elements against axial movement away from said shoulder, a valve element including an axially extended guide stem, means mounting said valve element for movements longitudinally of said passage toward and away from seating engagement with said valve seat, said last-mentioned means comprising a resilient member extending diametrically across said larger diameter passage portion and having a central aperture slidably receiving said stem, opposite ends of said member being received in said annular recess, a wall portion of said recess defining a notch, one end portion of said member including a tooth received in said notch to positively anchor said member against rotation on the axis of said passage, said valve element having an end portion which projects through the central opening of said annular retainer element to make seating engagement with said seat element upon movement of the valve element toward said seat element.

2. In a check valve for fluid pressure devices, means defining a fluid passage having an annular valve seat therein and an annular inwardly opening recess in axially spaced relation to said valve seat, a valve element including an axially extended guide stem, and means mounting said valve element for movements longitudinally of said passage toward and away from seating engagement with said valve seat and comprising a resilient member of greater length than the inner diameter of said annular recess extending diametrically across said passage and having a central aperture slidably receiving said stern, opposite ends of said member being received in said annular recess, a wall portion of said recess defining a notch, one of said opposite ends of said member including a tooth received in said notch to positively anchor said member against rotation on the axis of said passage.

References Cited in the file of this patent UNITED STATES PATENTS 305,841 Palmer Sept. 30, 1884 1,297,312 Barker Mar. 18, 1919 1,860,004 'Yardley May 24, 1932 2,011,812 Hatcher et al. Aug. 20, 1935 2,012,944 Ball Sept. 3, 1935 2,095,316 Davis Oct. 12, 1937 2,278,696 George Apr. 7, 1942 2,502,552 Baierlein Apr. 4, 1950 2,593,522 Barnes Apr. 22, 1952 2,870,784 Walls Jan. 27, 1959 FOREIGN PATENTS 1,083,070 France June 23, 1954

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