Abstract
A diaphragm pump and a valve system each include a valve plate having a planar valve engaging surface, a plurality of planar valve seats formed in the valve engaging surface, and a hole extending through each of the valve seats to an opposite face. Valves are disposed in the valve seats. Each of the valves includes a stem having a longitudinal axis extending through an associated one of the holes, and a flap at a first end of the valve extending transversely to the longitudinal axis. The stem and the flap have a non-circular cross-section, and a width of the flap and stem transverse to the longitudinal axis is greater than a depth of the flap and stem transverse to the longitudinal axis along the valve.
Claims
1. A diaphragm pump comprising: a valve plate having a planar valve engaging surface, a plurality of planar valve seats formed in the valve engaging surface, and a hole extending through each of the valve seats to an opposite face; a plurality of valves disposed in the valve seats, each of the valves comprising: a stem having a longitudinal axis extending through an associated one of the holes, and a flap at a first end of the valve extending transversely to the longitudinal axis, the stem and the flap having non-circular cross-section, wherein a width of the flap and stem transverse to the longitudinal axis is greater than a depth of the flap and stem transverse to the longitudinal axis along the valve.
2. The diaphragm pump according to claim 1, wherein the valve stem comprises a portion of increased cross-section spaced apart from the flap.
3. The diaphragm pump according to claim 2, wherein a thickness of the valve plate through the valve seat is greater than a distance between the flap and the portion of increased cross-section of the stem in a relaxed condition.
4. The diaphragm pump according to claim 1, wherein the flap comprises a concave valve plate engagement surface.
5. The diaphragm pump according to claim 1, wherein the flap has an elliptical periphery.
6. The diaphragm pump according to claim 1, wherein the plurality of valves comprise inlet valves.
7. The diaphragm pump according to claim 1, wherein the plurality of valves comprise outlet valves.
8. The diaphragm pump according to claim 1, wherein the plurality of valves comprise inlet valves mounted on a first face of the valve plate and outlet valves mounted on an opposite face of the valve plate.
9. The diaphragm pump according to claim 8, wherein the inlet valves and the outlet valves are interchangeable.
10. The diaphragm pump according to claim 1, comprising a unitary wobble plate and a plurality of distinct diaphragms.
11. The diaphragm pump according to claim 1, wherein the valve plate comprises a radiused transition from each of the valve seats to an associate one of the holes.
12. The diaphragm pump according to claim 1, comprising: a wobble plate; a plurality of diaphragms; a motor; an inlet port; and an outlet port.
13. The diaphragm pump according to claim 1, wherein the plurality of valves comprise an elastic material selected from the group consisting of ethylene propylene diene monomer (EPDM), Fluorine Kautschuk Material (FKM), or materials containing butadiene and sodium (BUNA).
14. A flexible valve comprising: a stem having a longitudinal axis; a flap at a first end of the valve extending transversely to the longitudinal axis, the stem and the flap having non-circular cross-section, wherein a ratio of a width to depth transverse to the axis is constant along the valve; a portion of increased cross-section spaced apart from the flap.
15. The flexible valve according to claim 14, wherein the flap comprises a concave portion facing the stem engagement surface.
16. The flexible valve according to claim 14, wherein the flap has an elliptical periphery.
17. The flexible valve according to claim 15, wherein the flap has an elliptical periphery.
18. A valve system comprising: a valve plate having a planar valve engaging surface, a plurality of planar valve seats formed in the valve engaging surface, and a hole extending through each of the valve seats to an opposite face; a plurality of valves disposed in the valve seats, each of the valves comprising: a stem having a longitudinal axis extending through an associated one of the holes, and a flap at a first end of the valve extending transversely to the longitudinal axis, the stem and the flap having non-circular cross-section, wherein a width of the flap and the stem transverse to the longitudinal axis is greater than a depth of the flap and stem transverse to the longitudinal axis along the valve.
19. The valve system according to claim 18, wherein the valve stem comprises a portion of increased cross-section spaced apart from the flap.
20. The valve system according to claim 19, wherein a thickness of the valve plate through the valve seat is greater than a distance between the flap and the portion of increased cross-section of the stem in a relaxed condition.
21. The valve system according to claim 20, wherein the stem of each valve is stretched when mounted to form a seal at each end of the hole in which the valve is mounted.
22. The valve system according to claim 18, wherein the plurality of valves comprise inlet valves mounted on a first face of the valve plate and outlet valves mounted on an opposite face of the valve plate.
23. The valve system according to claim 18, wherein the inlet valves and the outlet valves are interchangeable.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Referring now to the drawings, wherein like reference numerals and letters indicate corresponding structure throughout the several views:
[0019] FIG. 1 is a perspective view of a pump according to the principles of the present invention;
[0020] FIG. 2 is an end view of the pump housing and mounting brackets for the pump shown in FIG. 1;
[0021] FIG. 3 is a sectional view of the pump taken along line 3-3 of FIG. 2;
[0022] FIG. 4 is a first exploded perspective view of the pump head of the pump shown in FIG. 1;
[0023] FIG. 5 is a second exploded perspective view of the pump head of the pump shown in FIG. 1;
[0024] FIG. 6 is a sectional view of the pump head taken of the pump shown in FIG. 5 with the wobble plate and a diaphragm in a first position extending the diaphragm;
[0025] FIG. 7 is a detail sectional view of a portion of the pump head shown in FIG. 6;
[0026] FIG. 8 is a sectional view of the pump head taken along line 5-5 of FIG. 4 with the wobble plate in a second position with a diaphragm in a non-extended state;
[0027] FIG. 9 is a perspective view of a valve plate for the pump shown in FIG. 1;
[0028] FIG. 10 is a front view of the valve plate for the pump shown in FIG. 9;
[0029] FIG. 11 is a front view of the valve plate for the pump shown in FIG. 9 with the valves mounted; (this is shown in FIG. 3 in the original Provisional Patent Features document)
[0030] FIG. 12 is a side elevational view of the valve plate for the pump shown in FIG. 11 with the valves mounted and showing valve seats and fluid passages in broken lines;
[0031] FIG. 13 is a rear view of the valve plate for the pump shown in FIG. 9;
[0032] FIG. 14 is a rear view of the valve plate for the pump shown in FIG. 9 with the valves mounted;
[0033] FIG. 15 is a sectional view taken along line 15-15 of FIG. 14;
[0034] FIG. 16 is a detail sectional view of the valve plate, an inlet valve and an outlet valve shown in FIG. 15;
[0035] FIG. 17 is a bottom perspective view of a valve for the pump shown in FIG. 1;
[0036] FIG. 18 is a front view of the valve shown in FIG. 17;
[0037] FIG. 19 is side view of the valve shown in FIG. 17;
[0038] FIG. 20 is a sectional view of the valve taken along line 20-20 of FIG. 19;
[0039] FIG. 21 is bottom view of the valve shown in FIG. 17;
[0040] FIG. 22 is top view of the valve shown in FIG. 17;
[0041] FIG. 23 is a side view of the valve shown in FIG. 17 in a stretch preloaded state with an end portion of the stem removed as when mounted;
[0042] FIG. 24 is a sectional view of the valve taken along line 24-24 of FIG. 23;
[0043] FIG. 25 is a perspective view of a diaphragm assembly for the pump shown in FIG. 1;
[0044] FIG. 26 is a front elevational view of the diaphragm assembly shown in FIG. 25;
[0045] FIG. 27 is a side sectional view of the diaphragm assembly taken along line 27-27 of FIG. 26;
[0046] FIG. 28 is a side elevational view of the diaphragm assembly shown in FIG. 25;
[0047] FIG. 29 is a front perspective view of a diaphragm for the diaphragm assembly shown in FIG. 25;
[0048] FIG. 30 is a rear perspective view of the diaphragm shown in FIG. 29;
[0049] FIG. 31 is a front elevational view of the diaphragm shown in FIG. 29; and
[0050] FIG. 32 is a side elevational view of the diaphragm shown in FIG. 29.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0051] Referring now to the drawings and in particular to FIGS. 1 and 2, there is shown a diaphragm pump, generally designated (100). The pump (100) includes a head assembly (102) in a housing assembly (108) and a motor assembly (104) in a housing assembly (106). The pump (100) mounts with a bracket (110) to other structure and may include electrical and/or control components (112).
[0052] Referring now to FIG. 3, extending from the motor (104) is a motor shaft (118) that couples to and drives a wobble plate shaft (124) through a coupling (120). A wobble plate (122) actuates diaphragms (140). The wobble plate shaft (124) includes a cam surface (126), which is skewed relative to a longitudinal axis of the shaft (124) and therefore imparts a wobble as the wobble plate shaft (124) rotates to convert axial motion into oscillation of the wobble plate (122). In the embodiment shown the pump (100) includes five diaphragms, such as shown in FIGS. 4-5. The face of the wobble plate (122) moves in slightly arcing motion that stretches and deforms each of the spaced diaphragms (140) in turn. In the embodiment shown, the pump (100) includes five chambers and five sets of diaphragms (140), associated inlet valves (170A) and outlet valves (170B). However, other numbers of diaphragms and associated valves are also possible. As the wobble plate (122) rotates and oscillates back and forth or wobbles, the diaphragms (140) are actuated and the fluid is pumped through the head (102) from a fluid outlet (114) to a fluid discharge port (116).
[0053] Referring now to FIGS. 4 and 5, the head (102) generally includes the wobble plate (122) and five annularly space diaphragm engagement members (128). The engagement members (128) are aligned with and extend through orifices (132) in a diaphragm plate (130). The diaphragm plate (130) receives the five diaphragms (140) and abuts a valve plate (150). The valve plate (150) includes an inlet valve mounting surface (152) on one face and an outlet valve mounting surface (154) on an opposite face. The inlet valve mounting surface (152) has five valve seats (156) aligning with the diaphragms (140). An inlet valve element (170A) mounts in an associated valve seat (156) while an outlet valve element (170B) extends from the opposite side (154) and mounts with an opposite orientation to the associated inlet valve element (170A). The valve plate makes a sealed engagement with gaskets (182) to an end housing (180) of the head (102). The end housing (180) defines fluid channels to fluidly connect the fluid inlet port (114) to the valves (170A) and (170B) and the diaphragms (140). The fluid ports (114) and (116) may include thread connectors, bayonet type connectors, or other quick connects/disconnects and may also have adapters for coupling to various types and sizes of fittings for different applications.
[0054] Referring now to FIGS. 6-8, the operation of the diaphragms (140) and valves (170A) and (170B) can be understood. The pumped fluid flows from the inlet port (114) through fluid passages (190) to the inlet valves (170A). When an associate diaphragm is in a mid-stroke position, as shown in FIG. 8, in operation an aligned inlet valve (170A) would open and draw fluid through the inlet valve (170A). When the diaphragm is pushed by movement of the wobble plate (122), the diaphragm (140) expands outward as shown in FIG. 7. In operation this closes the inlet valve (170A) while the associated outlet valve (170B) opens. Fluid then flows through fluid passages (192) and to the outlet port (116). The pumped fluid generally flows through an inlet port (170A) through the head (102) and exits through an outlet port (170B). The pumped fluid is initially drawn from the inlet port (170A) into the pumping chambers (200A), (200B) and (200C) through the valve plate assembly (108) by the diaphragm (116). The pumped fluid then passes through an opening in the center of the valve plate (108) and through the outlet cavity (202) to the outlet port (170B).
[0055] Referring to FIGS. 9-16, the valve plate (150) of the present invention is shown. The valve plate (150) has recessed valve seats (156) formed in the inlet valve mounting surface (152). Unlike conventional valve seats with a rounded or curved surface, each of the valve seats (156) has a planar surface for engagement with flaps of associated inlet valve elements (170A). Flaps of the outlet valve elements (170B) engage the outlet valve surface (154). As explained hereinafter, the valves (170) are configured with an arcing engagement surface that is easily molded and provides a biasing force to maintain engagement with the valve seat (156). The configuration of the valve elements (170) with improved sealing helps to minimize residual fluid during flushing. Therefore, more difficult machining of a valve plate is avoided due to simpler geometry.
[0056] As shown in FIG. 10, the valve plate (150) includes inlet valve mounting holes (166) and outlet valve mounting holes (168) for receiving inlet valve elements (170A) and outlet valve elements (170B) respectively. The holes (166) and (168) have a non-circular cross-section, such as an oval cross-section to receive the complementary non-circular stem portions, such as oval cross-sections, of valve elements (170). To facilitate acceptance of the valve elements (170) and to avoid sharp edges that may tear the elastic valve elements (170), the corners proximate the ends of the inlet valve mounting holes (166) and the outlet valve holes (168) are radiused corners (160), shown most clearly in FIG. 16, to decrease stress on the valve elements (170). The valve plate (150) also has inlet fluid passages (162) extending through the thickness of the valve plate (150) disposed around the inlet valve mounting holes (166), and outlet fluid passages (164) extending through the thickness of the valve plate (150) disposed radially outward in an arc around the outlet valve mounting holes (168). The fluid passages (166) and (168) have radiused edges on the end of the passage covered by the flap (172). Such rounded edges decrease stress and wear of the valve flap (172). It is also appreciated that such radiused edges are easier to machine relative to conventional pumps due to the planar surfaces in the valve seats (156) and the outlet valve mounting surface (154). It can be appreciated that although the valve plate (150) as shown has ten inlet fluid passages (162) for each inlet valve and six outlet fluid passages (164) for each outlet valve, different numbers and/or diameters and/or arrangements are envisioned depending upon the application and requirements for a particular pump. However, the fluid passages (162) and (164) must be positioned so that they may be covered by a flap of a corresponding valve element (170).
[0057] It is appreciated that the shape and arrangement of the valve seats (156), the valve elements (170A) and (170B), the valve mounting holes (166) and (168), and the fluid passages (162) and (164), achieves improved performance and efficiencies as compared to similarly sized conventional pumps due to greater flow area.
[0058] Referring to FIGS. 17-22, each of the valve elements (170) is configured initially to ease insertion and mounting to the valve plate. The valve elements (170) each include a flap (172) with a stem extending from a first face (172A) of the flap (170) and defining a longitudinal axis. The flap (172) is flexible and configured to deflect to open and close. A first portion of the stem (174) extends to an intermediate portion (176) that has a greater transverse width and depth than the stem portion. An end portion (178) extends from the intermediate portion and is narrower in both depth and width than the first stem portion and the intermediate stem portion (176). It is appreciated that the width of all portions (172), (174) and (176) have a greater first transverse dimension (width) than a second transverse dimension (depth). The peripheries of the portions (172), (174), (176) may be elliptical or oval, for example. The valve elements (170) may be used as either inlet valves (170A) or outlet valves (170B) and are interchangeable. The valve elements (170) are made of a durable molded elastic material. Examples of suitable materials include ethylene propylene diene monomer (EPDM), Fluorine Kautschuk Material (FKM), or materials containing butadiene and sodium, such as BUNA. It is also appreciated that the face (172A) of the flap facing the stem (174) has an angled surface that forms a slightly angled surface that may be convex with an edge of the flap (170) longitudinally closer to the end (178) of the stem to improvement engagement with planar mounting surfaces of the valve plate.
[0059] The valve elements (170) mount to the valve plate by being pulled by the end portion (178) through a corresponding oval hole (166) or (168). The holes (166) and (168) have a larger cross section than the end portion of the stem (178) to facilitate insertion, so that the end portion (178) may be gripped for pulling through the hole (166) or (168). The length of the first portion (174) of the stem as molded is less than the length of a corresponding hole (166) or (168) through the valve plate. Therefore, the valve clement (170) must be stretched so that the widened intermediate portion (176) is pulled through the hole (166) or (168) and then engages a valve mounting surface (152) or (154). Once a valve element (170) is fully inserted, the end portion (178) is trimmed and the valve element (170) is configured as shown in FIGS. 23 and 24. It is appreciated, that the stem end in the widened portion (176) acts as a plug and maintains the valve clement (170) in an associated hole (166) or (168). In addition, the first portion (174) is stretched and lengthened compared to an initial molded configuration. It can be appreciated that with this mounting arrangement, each of the valve elements (170) is preloaded and pressed against both faces of the valve plate (150). The improved sealing at edges of the flap (172) of such an arrangement prevents residual fluid from being trapped around the stem (174).
[0060] Referring to FIGS. 25-28, the diaphragms (140) and engagement with the wobble plate (122) are shown. The engagement members (128) extend as cylinders spaced about a periphery of the wobble plate (122). Referring to FIGS. 29-32, each diaphragm includes a deformable portion (144) that engages pumped fluid and is extended and retracted due to the motion of the wobble plate (122). Each diaphragm (140) also includes an outer lip (142) to seal against the diaphragm plate, as shown, for example, in FIG. 7. An internal support body (148) supports the deformable portion, as also shown in FIG. 7. The internal support body (148) bonds to the deformable portion (144) as well as forming a mechanical coupling. A threaded male connector (146) extends from the back of the diaphragm (140) from the internal support body (148) and is configured to mate with a complementary female threaded hole of a corresponding diaphragm engagement member (128), such as shown in FIG. 25. Beads at the edges (142) of the diaphragms (140) are clamped so that the diaphragms (140) do not unscrew.
[0061] With the geometries achieved by the present invention, increases over conventional pumps having a comparable size due to changing the conventional round/circular passage layout to an elliptical passage and increases in flow passage size may be achieved. Conventional pumps having a comparable size may have four or five chambers. It is appreciated that five chambers, diaphragms, and sets of valves requires less flow through each valve than four. However, further changing the geometries of components from round to oval/elliptical increased the flow area by approximately an additional 30% at the inlet and outlets of each chamber by adding more through holes/passages than is possible with components and arrangements of a conventional five chamber pump of comparable size having rounds geometries. Moreover, increases of more than 60% may be achieved over the conventional four chamber pump of comparable size with round components. Moreover, by improving the ratio flow/area of the passages for the same flow, volumetric efficiency improves and fluid shear is reduced. It is appreciated that pumping capacity and performance achieves surprising increases over a pump of comparable size.
[0062] It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
