Diaphragm Pumps with Chamber Crossventing
Illustrative embodiments of diaphragm pumps with chamber crossventing, and methods of operating such pumps, are disclosed. In at least one illustrative embodiment, a method of operating a diaphragm pump may comprise communicating compressed fluid from a compressed fluid inlet to a first motive fluid chamber to cause first and second diaphragms to move to a first end-of-stroke position, communicating compressed fluid from the first motive fluid chamber to a second motive fluid chamber while the first and second diaphragms are in the first end-of-stroke position, communicating compressed fluid from the compressed fluid inlet to the second motive fluid chamber to cause the first and second diaphragms to move to a second end-of-stroke position, and communicating compressed fluid from the second motive fluid chamber to the first motive fluid chamber while the first and second diaphragms are in the second end-of-stroke position.
This application claims the benefit of U.S. Provisional Patent Application No. 61/839,703, filed Jun. 26, 2013, and U.S. Provisional Patent Application No. 61/895,796, filed Oct. 25, 2013 (both entitled “Energy Efficiency Enhancements for Air Operated Diaphragm Pumps”). The entire disclosures of both of the foregoing applications are incorporated by reference herein.
TECHNICAL FIELDThe present disclosure relates, generally, to diaphragm pumps and, more particularly, to diaphragm pumps with chamber crossventing.
BACKGROUNDDouble diaphragm pumps alternately pressurize and exhaust two opposing motive fluid chambers to deliver pumped media during each stroke of the pump. Pressurizing the motive fluid chambers often results in operating efficiency losses as some of the motive fluid communicated to the chambers during each stroke does not contribute to the pumping action. In an attempt to mitigate this shortcoming, some prior pumps have interrupted the supply of motive fluid part of the way through each stroke to minimize the amount of motive fluid that does not contribute to the pumping action. Such pumps, however, may have limited utility in applications where it is desirable for the pump to have access to the energy of the motive fluid source throughout each stroke (e.g., when pumping media at higher head pressures).
SUMMARYAccording to one aspect, a diaphragm pump may comprise a housing defining a first cavity and a second cavity, a first diaphragm disposed in the first cavity to separate the first cavity into a first motive fluid chamber and a first pumped media chamber, a second diaphragm disposed in the second cavity to separate the second cavity into a second motive fluid chamber and a second pumped media chamber, a shaft coupled between the first and second diaphragms and configured to move reciprocally with the first and second diaphragms between a first end-of-stroke position and a second end-of-stroke position, a main valve fluidly coupled between a compressed fluid inlet and the first and second motive fluid chambers, and a crossvent valve fluidly coupled between the first and second motive fluid chambers. The main valve may be movable between (i) a first position in which the main valve is configured to communicate compressed fluid from the compressed fluid inlet to the first motive fluid chamber and (ii) a second position in which the main valve is configured to communicate compressed fluid from the compressed fluid inlet to the second motive fluid chamber. The crossvent valve may be configured to (i) communicate compressed fluid between the first and second motive fluid chambers during a time period when the main valve is between the first and second positions and (ii) resist communication of compressed fluid between the first and second motive fluid chambers when the main valve is in either of the first and second positions.
In some embodiments, the main valve may be configured to resist communication of compressed fluid from the compressed fluid inlet to the first and second motive fluid chambers during the time period. The second motive fluid chamber may be fluidly coupled to an exhaust chamber when the main valve is in the first position, and the first motive fluid chamber may be fluidly coupled to the exhaust chamber when the main valve is in the second position. In some embodiments, the first and second motive fluid chambers are not fluidly coupled to the exhaust chamber during the time period.
In some embodiments, the diaphragm pump may further comprise a pilot valve configured to selectively communicate compressed fluid from the compressed fluid inlet to a pilot chamber of the main valve to control movement of the main valve between the first and second positions. The pilot valve may be further configured to selectively communicate compressed fluid from the compressed fluid inlet to a pilot chamber of the crossvent valve to cause the crossvent valve to communicate compressed fluid between the first and second motive fluid chambers during the time period.
In some embodiments, the crossvent valve may comprise a spool extending into the first motive fluid chamber such that the spool is configured to be actuated by the first diaphragm when in the first end-of-stroke position to cause the crossvent valve to communicate compressed fluid between the first and second motive fluid chambers. The spool of the crossvent valve may also extend into the second motive fluid chamber such that the spool is also configured to be actuated by the second diaphragm when in the second end-of-stroke position to cause the crossvent valve to communicate compressed fluid between the first and second motive fluid chambers. The spool of the crossvent valve may be biased toward a position in which the crossvent valve resists communication of compressed fluid between the first and second motive fluid chambers when the first and second diaphragms are between the first and second end-of-stroke positions.
According to another aspect, a diaphragm pump may comprise a housing defining a first cavity and a second cavity, a first diaphragm disposed in the first cavity to separate the first cavity into a first motive fluid chamber and a first pumped media chamber, a second diaphragm disposed in the second cavity to separate the second cavity into a second motive fluid chamber and a second pumped media chamber, a shaft coupled between the first and second diaphragms and configured to move reciprocally with the first and second diaphragms between a first end-of-stroke position and a second end-of-stroke position, and a main valve fluidly coupled between a compressed fluid inlet and the first and second motive fluid chambers. The main valve may be movable between (i) a first position in which the main valve is configured to communicate compressed fluid from the compressed fluid inlet to the first motive fluid chamber, (ii) a second position in which the main valve is configured to communicate compressed fluid from the compressed fluid inlet to the second motive fluid chamber, and (iii) a third position in which the main valve is configured to communicate compressed fluid between the first and second motive fluid chambers, the third position being between the first and second positions.
In some embodiments, the main valve may be configured to resist communication of compressed fluid between the first and second motive fluid chambers when the main valve is in either of the first and second positions. The main valve may be configured to resist communication of compressed fluid from the compressed fluid inlet to the first and second motive fluid chambers when the main valve is in the third position. The second motive fluid chamber may be fluidly coupled to an exhaust chamber when the main valve is in the first position, and the first motive fluid chamber may be fluidly coupled to the exhaust chamber when the main valve is in the second position. In some embodiments, the first and second motive fluid chambers are not fluidly coupled to the exhaust chamber when the main valve is in the third position.
In some embodiments, the diaphragm pump may further comprise a pilot valve configured to selectively communicate compressed fluid from the compressed fluid inlet to a pilot chamber of the main valve to control movement of the main valve between the first and second positions. The diaphragm pump may further comprise a flow control valve configured to control a flow rate of the compressed fluid communicated to the pilot chamber of the main valve to control a speed at which the main valve moves between the first and second positions.
According to yet another aspect, a method of operating a diaphragm pump may comprise communicating compressed fluid from a compressed fluid inlet to a first motive fluid chamber to cause first and second diaphragms to move to a first end-of-stroke position, communicating compressed fluid from the first motive fluid chamber to a second motive fluid chamber while the first and second diaphragms are in the first end-of-stroke position, communicating compressed fluid from the compressed fluid inlet to the second motive fluid chamber to cause the first and second diaphragms to move to a second end-of-stroke position, and communicating compressed fluid from the second motive fluid chamber to the first motive fluid chamber while the first and second diaphragms are in the second end-of-stroke position.
In some embodiments, compressed fluid is not communicated from the compressed fluid inlet to either of the first and second motive fluid chambers while compressed fluid is being communicated between the first and second motive fluid chambers. The method may further comprise fluidly coupling the second motive fluid chamber to an exhaust chamber while communicating compressed fluid from the compressed fluid inlet to the first motive fluid chamber. The method may further comprise fluidly coupling the first motive fluid chamber to the exhaust chamber while communicating compressed fluid from the compressed fluid inlet to the second motive fluid chamber. In some embodiments, the first and second motive fluid chambers are not fluidly coupled to the exhaust chamber while compressed fluid is being communicated between the first and second motive fluid chambers.
In some embodiments, shifting a main valve of the diaphragm pump to a first position may cause compressed fluid to be communicated from the compressed fluid inlet to the first motive fluid chamber, shifting the main valve to a second position may cause compressed fluid to be communicated from the compressed fluid inlet to the second motive fluid chamber, and compressed fluid may be communicated between the first and second motive fluid chambers while the main valve is shifting between the first and second positions. Compressed fluid may be communicated from the compressed fluid inlet to the first motive fluid chamber until the first and second diaphragms reach the first end-of-stroke position, and compressed fluid may be communicated from the compressed fluid inlet to the second motive fluid chamber until the first and second diaphragms reach the second end-of-stroke position.
The concepts described in the present disclosure are illustrated by way of example and not by way of limitation in the accompanying figures. For simplicity and clarity of illustration, elements illustrated in the figures are not necessarily drawn to scale. For example, the dimensions of some elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference labels may be repeated among the figures to indicate corresponding or analogous elements.
While the concepts of the present disclosure are susceptible to various modifications and alternative forms, specific exemplary embodiments thereof have been shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that there is no intent to limit the concepts of the present disclosure to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure.
Referring now to
The shaft 30 illustrated in
The pump 10 includes an inlet 32 for the supply of a compressed fluid (e.g., compressed air, another pressurized gas, hydraulic fluid, etc.) and a main valve 34 for alternately supplying the compressed fluid to the motive fluid chambers 26, 28 to drive reciprocation of the diaphragms 18, 20 and the shaft 30. The main valve 34 is fluidly coupled between the inlet 32 and the motive fluid chambers 26, 28. When the main valve 34 supplies compressed fluid to the motive fluid chamber 26 (while in a position 60), the main valve 34 places an exhaust assembly 36 in communication with the other motive fluid chamber 28 to permit fluid to be expelled therefrom. Conversely, when the main valve 34 supplies compressed fluid to the motive fluid chamber 28 (while in a position 61), the main valve 34 places the motive fluid chamber 26 in communication with the exhaust assembly 36. In the illustrative embodiment of the pump 10, movement of the main valve 34 between the positions 60, 61 is controlled by a pilot valve 35 (shown diagrammatically in
As seen in
The exhaust assembly 36 of the pump 10 includes an exhaust chamber 50 and a muffler 52 that is received in the exhaust chamber 50. In the illustrative embodiment, the main valve 34 alternately couples one of the motive fluid chambers 26, 28 (whichever of the motive fluid chambers 26, 28 is not being supplied with compressed fluid by the main valve 34) to the exhaust assembly 36 to allow any fluid in that motive fluid chamber 26, 28 to be vented to the atmosphere. It is contemplated that, in other embodiments, the pump 10 might use other mechanisms to selectively couple the motive fluid chambers 26, 28 to the exhaust assembly 36 (e.g., “quick dump check valves” positioned between the main valve 34 and the motive fluid chambers 26, 28).
During operation of the pump 10, as the main valve 34, the pilot valve 35, and the exhaust assembly 36 cooperate to effect the reciprocation of the diaphragms 18, 20 and the shaft 30, the pumped media chambers 22, 24 alternately expand and contract to create respective low and high pressure within the respective pumped media chambers 22, 24. The pumped media chambers 22, 24 each communicate with a pumped media inlet 38 that may be connected to a source of fluid to be pumped (also referred to herein as “pumped media”) and also each communicate with a pumped media outlet 40 that may be connected to a receptacle for the fluid being pumped. Check valves (not shown) ensure that the fluid being pumped moves only from the pumped media inlet 38 toward the pumped media outlet 40. For instance, when the pumped media chamber 22 expands, the resulting negative pressure draws fluid from the pumped media inlet 38 into the pumped media chamber 22. Simultaneously, the other pumped media chamber 24 contracts, which creates positive pressure to force fluid contained therein to the pumped media outlet 40. Subsequently, as the shaft 30 and the diaphragms 18, 20 move in the opposite direction, the pumped media chamber 22 will contract and the pumped media chamber 24 will expand (forcing fluid contained in the pumped media chamber 24 to the pumped media outlet 40 and drawing fluid from the pumped media inlet 38 into the pumped media chamber 24).
Referring now to
Various flow paths of compressed fluid through the pump 10 during the “Begin Left Stroke” stage 55, the “End Left Stroke” stage 54, and the “Begin Right Stroke” stage 57 are illustrated in
Referring now to
The pump 10 illustratively includes a crossvent valve 56 fluidly coupled between the motive fluid chambers 26, 28, as suggested in
Referring now to
Referring now to
Referring generally now to
As seen in
The main valve 34 is shown (diagrammatically) in position 61 in
The spool 42 of the pilot valve 35 extends into each of the motive fluid chambers 26, 28, as shown in
The crossvent valve 56 is fluidly coupled to the motive fluid chambers 26, 28 via conduits 93, 95, respectively, as shown in
During the operating stage of the pump 10 shown in
The shaft 30 reaches the end-of-stroke position shown in
The position 63 of the main valve 34 (shown diagrammatically in
The compressed fluid pressure communicated to the pilot chamber 76 of the main valve 34 is also communicated to the pilot chamber 88 of the crossvent valve 56 via the conduit 91, as shown in
As seen in
The main valve 34 is shown in the position 60 in
During operation of the pump 10 as shown in
Referring now to
As seen in
In the position 161 shown in
The pump 110 includes a crossvent valve 182 having a spool 167 extending into each of the motive fluid chambers 126, 128 as shown in
The shaft 130 has not yet reached the right end-of-stroke position in
Referring now to
The pump 210 shown in
The main valve 237 is fluidly coupled to the motive fluid chambers 226, 228 via conduits 211, 213, respectively. When the main valve 237 is in either the position 260 or the position 261, the main valve 237 resists communication between the motive fluid chambers 226, 228 via the conduits 211, 213. For example, as shown in
Referring to
While certain illustrative embodiments have been described in detail in the figures and the foregoing description, such an illustration and description is to be considered as exemplary and not restrictive in character, it being understood that only illustrative embodiments have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected. There are a plurality of advantages of the present disclosure arising from the various features of the apparatus, systems, and methods described herein. It will be noted that alternative embodiments of the apparatus, systems, and methods of the present disclosure may not include all of the features described yet still benefit from at least some of the advantages of such features. Those of ordinary skill in the art may readily devise their own implementations of the apparatus, systems, and methods that incorporate one or more of the features of the present disclosure.
Claims
1. A diaphragm pump comprising:
- a housing defining a first cavity and a second cavity;
- a first diaphragm disposed in the first cavity to separate the first cavity into a first motive fluid chamber and a first pumped media chamber;
- a second diaphragm disposed in the second cavity to separate the second cavity into a second motive fluid chamber and a second pumped media chamber;
- a shaft coupled between the first and second diaphragms and configured to move reciprocally with the first and second diaphragms between a first end-of-stroke position and a second end-of-stroke position;
- a main valve fluidly coupled between a compressed fluid inlet and the first and second motive fluid chambers, the main valve being movable between (i) a first position in which the main valve is configured to communicate compressed fluid from the compressed fluid inlet to the first motive fluid chamber and (ii) a second position in which the main valve is configured to communicate compressed fluid from the compressed fluid inlet to the second motive fluid chamber; and
- a crossvent valve fluidly coupled between the first and second motive fluid chambers, the crossvent valve being configured to (i) communicate compressed fluid between the first and second motive fluid chambers during a time period when the main valve is between the first and second positions and (ii) resist communication of compressed fluid between the first and second motive fluid chambers when the main valve is in either of the first and second positions.
2. The diaphragm pump of claim 1, wherein the main valve is configured to resist communication of compressed fluid from the compressed fluid inlet to the first and second motive fluid chambers during the time period.
3. The diaphragm pump of claim 1, wherein:
- the second motive fluid chamber is fluidly coupled to an exhaust chamber when the main valve is in the first position;
- the first motive fluid chamber is fluidly coupled to the exhaust chamber when the main valve is in the second position; and
- the first and second motive fluid chambers are not fluidly coupled to the exhaust chamber during the time period.
4. The diaphragm pump of claim 1, further comprising a pilot valve configured to selectively communicate compressed fluid from the compressed fluid inlet to a pilot chamber of the main valve to control movement of the main valve between the first and second positions.
5. The diaphragm pump of claim 4, wherein the pilot valve is further configured to selectively communicate compressed fluid from the compressed fluid inlet to a pilot chamber of the crossvent valve to cause the crossvent valve to communicate compressed fluid between the first and second motive fluid chambers during the time period.
6. The diaphragm pump of claim 1, wherein the crossvent valve comprises a spool extending into the first motive fluid chamber such that the spool is configured to be actuated by the first diaphragm when in the first end-of-stroke position to cause the crossvent valve to communicate compressed fluid between the first and second motive fluid chambers.
7. The diaphragm pump of claim 6, wherein the spool of the crossvent valve also extends into the second motive fluid chamber such that the spool is also configured to be actuated by the second diaphragm when in the second end-of-stroke position to cause the crossvent valve to communicate compressed fluid between the first and second motive fluid chambers.
8. The diaphragm pump of claim 7, wherein the spool of the crossvent valve is biased toward a position in which the crossvent valve resists communication of compressed fluid between the first and second motive fluid chambers when the first and second diaphragms are between the first and second end-of-stroke positions.
9. A diaphragm pump comprising:
- a housing defining a first cavity and a second cavity;
- a first diaphragm disposed in the first cavity to separate the first cavity into a first motive fluid chamber and a first pumped media chamber;
- a second diaphragm disposed in the second cavity to separate the second cavity into a second motive fluid chamber and a second pumped media chamber;
- a shaft coupled between the first and second diaphragms and configured to move reciprocally with the first and second diaphragms between a first end-of-stroke position and a second end-of-stroke position; and
- a main valve fluidly coupled between a compressed fluid inlet and the first and second motive fluid chambers, the main valve being movable between (i) a first position in which the main valve is configured to communicate compressed fluid from the compressed fluid inlet to the first motive fluid chamber, (ii) a second position in which the main valve is configured to communicate compressed fluid from the compressed fluid inlet to the second motive fluid chamber, and (iii) a third position in which the main valve is configured to communicate compressed fluid between the first and second motive fluid chambers, the third position being between the first and second positions.
10. The diaphragm pump of claim 9, wherein the main valve is configured to resist communication of compressed fluid between the first and second motive fluid chambers when the main valve is in either of the first and second positions.
11. The diaphragm pump of claim 9, wherein the main valve is configured to resist communication of compressed fluid from the compressed fluid inlet to the first and second motive fluid chambers when the main valve is in the third position.
12. The diaphragm pump of claim 9, wherein:
- the second motive fluid chamber is fluidly coupled to an exhaust chamber when the main valve is in the first position;
- the first motive fluid chamber is fluidly coupled to the exhaust chamber when the main valve is in the second position; and
- the first and second motive fluid chambers are not fluidly coupled to the exhaust chamber when the main valve is in the third position.
13. The diaphragm pump of claim 9, further comprising a pilot valve configured to selectively communicate compressed fluid from the compressed fluid inlet to a pilot chamber of the main valve to control movement of the main valve between the first and second positions.
14. The diaphragm pump of claim 13, further comprising a flow control valve configured to control a flow rate of the compressed fluid communicated to the pilot chamber of the main valve to control a speed at which the main valve moves between the first and second positions.
15. A method of operating a diaphragm pump comprising a housing defining a first cavity and a second cavity, a first diaphragm disposed in the first cavity to separate the first cavity into a first motive fluid chamber and a first pumped media chamber, a second diaphragm disposed in the second cavity to separate the second cavity into a second motive fluid chamber and a second pumped media chamber, a shaft coupled between the first and second diaphragms, and a compressed fluid inlet, the method comprising:
- communicating compressed fluid from the compressed fluid inlet to the first motive fluid chamber to cause the first and second diaphragms to move to a first end-of-stroke position;
- communicating compressed fluid from the first motive fluid chamber to the second motive fluid chamber while the first and second diaphragms are in the first end-of-stroke position;
- communicating compressed fluid from the compressed fluid inlet to the second motive fluid chamber to cause the first and second diaphragms to move to a second end-of-stroke position; and
- communicating compressed fluid from the second motive fluid chamber to the first motive fluid chamber while the first and second diaphragms are in the second end-of-stroke position.
16. The method of claim 15, wherein compressed fluid is not communicated from the compressed fluid inlet to either of the first and second motive fluid chambers while compressed fluid is being communicated between the first and second motive fluid chambers.
17. The method of claim 15, further comprising:
- fluidly coupling the second motive fluid chamber to an exhaust chamber while communicating compressed fluid from the compressed fluid inlet to the first motive fluid chamber; and
- fluidly coupling the first motive fluid chamber to the exhaust chamber while communicating compressed fluid from the compressed fluid inlet to the second motive fluid chamber.
18. The method of claim 17, wherein the first and second motive fluid chambers are not fluidly coupled to the exhaust chamber while compressed fluid is being communicated between the first and second motive fluid chambers.
19. The method of claim 15, wherein:
- shifting a main valve of the diaphragm pump to a first position causes compressed fluid to be communicated from the compressed fluid inlet to the first motive fluid chamber;
- shifting the main valve to a second position causes compressed fluid to be communicated from the compressed fluid inlet to the second motive fluid chamber; and
- compressed fluid is communicated between the first and second motive fluid chambers while the main valve is shifting between the first and second positions.
20. The method of claim 15, wherein:
- compressed fluid is communicated from the compressed fluid inlet to the first motive fluid chamber until the first and second diaphragms reach the first end-of-stroke position; and
- compressed fluid is communicated from the compressed fluid inlet to the second motive fluid chamber until the first and second diaphragms reach the second end-of-stroke position.
Type: Application
Filed: Jun 26, 2014
Publication Date: Jan 1, 2015
Inventors: Jevawn Sebastian Roberts (Atlanta, GA), Michael Brace Orndorff (Douglasville, GA)
Application Number: 14/316,146
International Classification: F04B 43/073 (20060101);