Patent Application
20190168039
Not applicable.
Pressure control valves, or pressure regulators, are used to automatically increase, decrease, turn on, turn off, or otherwise regulate the flow of a liquid or gas at certain pressures. In many cases, these valves serve to maintain a reduced outlet pressure regardless of variations in the inlet pressure of the fluid. These types of pressure reducing valves are used primarily for safety purposes and can be implemented in a variety of areas, including the aircraft industry, cooking, the oil and gas industry, and many others. In one application, pressure control valves are used in compressed air foam systems (CAFS) used for firefighting, in which the value may be used to deliver an appropriate quantity of water or a mixture of water and surfactant. Many existing pressure control valves and regulators use a spring loaded poppet valve as the pressure reducing or restrictive element and a diaphragm to sense the pressure changes. A spring is typically used to exert a force on the sensing element and to open the valve.
In many cases, fire apparatuses are used in areas of both high pressure hydrants, where it is advantageous to reduce the pressure from the hydrants to the apparatus, and of low pressure hydrants, where it is not advantageous to reduce the pressure from the hydrants. One example would be area of different altitudes, where at lower levels there is more pressure due to the higher head of the water (and vice versa for higher altitude portions of the area). For cases where pressure may vary during use or by use, it is necessary to provide optional means of regulation, where the operator may selectively choose the operation best suited for the particular situation.
The present invention is directed to a pressure control valve or flow regulator with an incorporated shut-off mechanism for use between a pressurized liquid source and a pump inlet (the pump inlet being fluidically connected to the pressure regulator outlet). The flow regulator uses a piston with a plate, whereupon application of a pressurized fluid on the plate controls movement of the piston. Rather than a poppet valve, the piston moves axially within a pressure chamber as the pressure regulating component. The piston is capable of moving freely toward and away a sealing port allowing the user to control liquid flow to the flow outlet area. The piston, when positioned entirely forward such that it contacts the sealing port, is able to prevent the flow of liquid into the outlet area altogether. In alternate embodiments, a diaphragm may replace the piston and functional in substantially the same manner. For purposes of describing the invention, however, the term piston will be used.
In the preferred embodiment of the present invention, the pressure regulator is fluidically connected to a pressurized fluid supply (such as a pressurized air supply). While it is contemplated that any pressurized fluid may be used (such as air, water, or some other fluid), for ease of describing the invention, various embodiments may be described with reference to pressurized air. The invention, however, is not so limited. More preferably, the pressure regulator is fluidically connected at two points (one on either side of the piston plate), such that application of varying amounts of pressurized fluid on either side of the plate will control the lateral movement of the plate within the pressure chamber. When used in a compressed air foam system, the invention allows the engine powering the system to run at an increased rpm at the same discharge pressure. This provides numerous advantages in practical firefighting applications.
In certain implementations of the pressure regulator of the present invention, the flow regulator may further include a hand wheel attached at the rear of the pressure chamber. By turning the hand wheel, a moveable plate within the pressure chamber is brought forward, and thus the available stroke of the piston is reduced. This provides a manual override function for the regulator. When the hand wheel is turned such that the moveable plate is in the most forward position, the piston is held in place against the sealing port such that the flow is cut off entirely; conversely, when the hand wheel is turned such that the moveable plate is in the fully rearward position, full articulation of the piston is possible, thereby allowing full flow through the regulator.
These and other features, objects and advantages of the present invention will become better understood from a consideration of the following detailed description of the preferred embodiments and appended claims in conjunction with the drawings as described following:
The present invention is directed toward a single-piston pressure regulator with incorporated shut off mechanism. The pressure regulator may be manufactured as a single integrated piece or may be manufactured as separate pieces that are connected together to form the pressure regulator assembly. For ease of describing the invention, the components of the pressure regulator may be described herein as being connected. It is understood, however, that the description of elements equally applies to the embodiment in which the components are individually pieces joined together to form the assembly.
With regards to
In one embodiment, the flow inlet area 26 is at a generally 45° angle to the liquid flow chamber 6, as shown in
A piston 3 is situated inside the regulator 2 and is fitted to slide longitudinally within the regulator 2 along an axis that extends along the centerline of the regulator 2. The piston 3 includes a plate 40 and a shaft 7 extending from one side of the plate 40. The piston 3 has a number of faces that are positioned in different areas of the regulator 2: a forward face 41b of the plate 40, a rearward face 41a of the plate 40, and a forward face 4 on the shaft 7. In one embodiment, the shaft 7 may also include a beveled or tapered edge 5 on its forward face 4, as shown in
As mentioned above, the plate 40 of the piston 3 has a forward face 41b and a rearward face 41a. In the preferred embodiment, the diameter of the plate 40 of the piston 3 is substantially close to the diameter of the pressure chamber 8 such that the side surfaces of the plate 40 substantially create a seal with the walls 16 of the pressure chamber 8. Sealing elements 20 may be included between the side walls of the plate 40 and the walls 16 of the pressure chamber 8 to further facilitate sealing. These sealing elements 20 provide a fluid-tight seal, which allows the piston 3 to move along its longitudinal axis while preventing fluid from flowing between the outer surfaces of the plate 40 and the inner surface of the pressure chamber 8. Thus, because the plate 40 of the piston 3 creates a seal with the inner walls 16 of the pressure chamber 8, the pressure chamber 8 is effectively divided into two portions, a rearward pressure chamber 8a and a forward pressure chamber 8b—one on either side of the plate 40 of the piston 3 such that the rearward face 41a of the plate 40 is positioned inside the rearward chamber 8a and the forward face 41b of the plate 40 is positioned inside the forward chamber 8b. As described above, in one embodiment the shaft 7 has a forward face 4 and an adjacent beveled edge 5. The forward face 4 of the shaft 3 (and the adjacent beveled area 5) is situated inside the liquid flow chamber 6.
The flow inlet area 26 is configured to receive a liquid from a pressurized liquid source (not shown). The source may be, for example, a water tank, or water that is mixed with a surfactant either in a tank, or in a line that feeds the water from the tank to flow inlet area 26. The flow inlet area 26 is fluidically connected to the liquid flow chamber 6, which separates the flow inlet area 26 from the flow outlet area 24. A portion of the shaft 7 of the piston 3 is positioned inside the liquid flow chamber 6 and is configured to move within the liquid flow chamber 6 such that the regulator 2 moves between a fully opened position (as shown in
The liquid flow chamber 6 includes a sealing port 22 that works in conjunction with the piston 3 to seal the liquid flow chamber 6 and prohibit liquid flow through the liquid flow chamber 6. In one embodiment, the sealing port 22 is positioned between the liquid flow chamber 6 and the flow outlet area 24 such that when the piston 3 moves to its most forward position, liquid may enter at least a portion of the liquid flow chamber 6 through the flow inlet area 26, but cannot exit through the flow outlet area 24 because the sealing port 22 is closed by the piston 3 (as shown in
As indicated, the piston 3 is configured to move within the regulator 2 between open and closed positions due to pressures exerted on the various piston faces by the liquid flowing through the liquid flow chamber 6 and by a pressurized fluid introduced into the pressure chamber 8. In the preferred embodiment, a pressurized fluid source 44 is used to regulate the pressure of the fluid flowing into the pressure chamber 8. While it is understood that various applications may be used (such as pneumatic or hydraulic), because the preferred embodiment utilizes pneumatic pressure, the invention will be described using a description of a pneumatic pressure application. In the preferred embodiment, the regulator 2 is fluidically connected to a pressurized air source 44, preferably having two lines 54a. 54b for transmitting air from the pressurized air source 44 into the pressure chamber 8 of the regulator 2. One of the air supply lines 54a is preferably connected to the rearward pressure chamber 8a and the other air supply line 54b is connected to the forward pressure chamber 8b, such that pressurized air may be introduced into each chamber 8a, 8b independently. A valve 78a, 78b on each air supply line 54a, 54b allows for the selective operation of each air supply line 54a, 54b independently, allowing the operator to modify the amount of pressurized air introduced into each pressure chamber 8a, 8b. Varying the pressure introduced into either chamber 8a, 8b allows for the selective movement of the piston 3 within the regulator 2, allowing more precise regulation of liquid flow through the regulator 2. Further, the ability to introduce pressurized air on the forward face 41b of the piston plate 40 allows for a “dampening” effect on the movement of the piston 3. It is understood that as the piston 3 moves between its open and closed positions, the area on which the liquid flowing into the liquid flow chamber 6 exerts force on the piston shaft 7 changes (as more or less of the forward face 4 of the shaft 7 of the piston 3 is now disposed to the liquid). Though this change is minimal, this coupled with the changes in the supply pressure of the liquid as flow increases, results in variation of pressure at the pump inlet 64. While in most instances this does not present a problem, in foam applications, it does cause some variation in foam to water ratio. For this reason, the ability to variable introduce pressure into the forward pressure chamber 8b allows for the dampening or cushioning effect. The ability to vary the pressure on each side of the plate 40 allows for the resistance to opening or closing of the valve to be maintained in a balanced state during operation. For example, should the liquid flow pressure decrease during operation and the pressure in the rear pressure chamber 8b remain the same, without introduction of pressure into the forward pressure chamber 8a, the piston 3 would necessarily move toward a closed position. Introduction of pressure into the forward pressure chamber 8b can prohibit this undesired movement.
As noted above, in one embodiment of the pressure regulator 2 of the present invention, the pressure regulator 2 uses a wheel 28 to control the movement capabilities of the piston 3. In one embodiment, a substantially circular hand wheel 28 may be implemented. It is understood that any variation of wheel shape may be used, so long as the wheel 28 may be used to rotate a threaded shaft 30 connected to the wheel 28, thereby moving a plate 34 in a forward or rearward direction to change the area in which the piston 3 may move. The hand wheel 28 is connected to one end of the threaded shaft 30, while the plate 34 is located at the other end of the threaded shaft 30. As indicated above, a head cap 18 is connected to the rear pressure chamber 8a and this head cap 18 serves to enclose the rear pressure chamber 8a. This head cap 18 may be manufactured integral to the housing of the rear pressure chamber 8a or may be a separate piece positioned between the moveable plate 34 and the hand wheel 28 that is configured to be fitted, by welding, bolts, or other means to the end of the rear pressure chamber 8a. In either event, the head cap 18 is configured such that the threaded shaft 30 extends through the head cap 18 and into the rear pressure chamber 8a. The hand wheel 28 preferably remains on the exterior of the rear chamber 8a housing such that the wheel 28 can be accessed by the user during use of the regulator 2. The rotation of the hand wheel 28 by the user in turn causes the threaded shaft 30 to rotate, thus causing the movable plate 34 to move forward or rearward in the rear pressure chamber 8a.
In one embodiment, the threaded shaft 30 may extend from the hand wheel 28 into a hollow portion 10 of the piston 3. This hollow portion 10 of the piston 3 is designed to receive the end of the threaded shaft 30, but not to contact the threaded shaft 30 so that the piston 3 is not prohibited from sliding by the threaded shaft 30. In one embodiment, guide pins 38 are used to prohibit the movable plate 34 from rotating as the threaded shaft is rotated 30, thus allowing the plate 34 to only move forward or rearward depending on the rotation of the hand wheel 28. The guide pins 38 are preferably threaded into the end cap 18 at one end with the other ends extending through the moveable plate 34. In one embodiment, the guide pins 38 extend into hollow area 10 of the piston 3 to secure the piston 3 to the guide pins 38 while also allowing piston 3 to move freely toward and away from the sealing port 22 in order to control the flow of fluid in the fluid flow chamber 6. The outer diameter of the moveable plate 34 is such that it will engage the rear face 41a of the piston 3 as the plate 34 moves forward, thus limiting the rearward movement of piston 3. As the plate 34 continues to move into the rearward face 41a of the piston 3, the plate 34 forces the piston 3 into the sealing port 22, thereby preventing flow of water through the fluid flow chamber 6 altogether.
Thus, it may be seen that the hand wheel 28 provides a manual means to override the automatic pressure regulation of the regulator 2. By turning hand wheel 28, movable plate 34 may be moved forwardly or rearwardly depending upon the direction of rotation. Using right hand threads, turning hand wheel 28 clockwise would cause movable plate 34 to more forwardly, but the invention is not so limited. It may be seen that the position of movable plate 34 within the interior of the rear chamber 8a provides a stop to the maximum rearward movement of piston 3, and thus provides a manual override function to the degree to which the valve may open under automatic operation. If hand wheel 28 is turned such that movable plate 34 is fully forward, then it presses the forward face 4 of the shaft 7 of the piston 3 (and the beveled edge area 5) fully against the sealing port 22, thereby stopping the passage of liquid through fluid flow chamber 6 and out of the outlet area 24, and therefore stopping all flow through the regulator 2. Although the hand wheel 28 is shown as a manually controlled wheel in the illustrated implementation, various electronic, hydraulic, pneumatic, or other powered control means could be used to actuate the position of moveable plate 34.
The structure of the regulator 2 having now been described, its operation may be described as follows. Generally speaking, a first pressurized liquid flows from a pressurized liquid source (not shown) into the liquid flow chamber 6 through the flow inlet area 26. This flow of liquid exerts a pressure at the forward face 4 of the piston shaft 7, which is positioned inside the liquid flow chamber 6. In one embodiment, pressure is also exerted on the beveled portion 5 of the piston's shaft 7. This exertion of pressure on the forward face 4 and beveled portion 5 of the shaft 7 moves the piston rearward into the pressure chamber 8 (i.e. moving toward the fully open position), which serves to open the valve to allow flow through the liquid flow chamber 6 and out through the flow outlet area 24.
As the piston 3 moves into the pressure chamber 8, the user may selectively introduce pressurized air (or another pressurized fluid) into the pressure chamber 8 through the pressurized air inlets 55a, 55b located within the separate portions 8a, 8b of the pressure chamber 8 and fluidically connected to the pressurized air supply 44 (or other pressurized fluid supply) through the supply lines 54a, 54b. As pressurized air is introduced into the rearward pressure chamber 8a the pressure builds in the rear pressure chamber 8a. As the pressure in the rear pressure chamber 8a builds, the air exerts a force on the rear face 41a of the piston plate 40. Once the pressure exerted on the rear face 41a of the piston plate 40 increases to a certain point (sufficient to overcome the force exerted by the liquid at the front face 4 of the piston shaft 3), the piston 3 is pushed back forward. The piston 3 may continue to move forward until the pressures at the rear face 41a of the piston plate 40 and at the front face 4 and beveled portion 5 of the piston shaft 7 equalize, thus creating a regulation of the pressure of fluid that flows out of the outlet flow area 24 of the regulator. The precise position at which the piston 3 reaches equilibrium may be modified by varying the areas of the forward parts of the piston shaft 3 (forward face 4 and beveled portion 5) proportionally to the area of the rear face 41a of the piston plate 40. In one embodiment, the rearward face 41a of the piston plate 40 has a diameter of 6″ whereas the diameter of piston shaft 3 is 4 ½″ and the diameter of the beveled portion 5 is 3 ¾″. Because the area onto which fluid pressure may be asserted is greater at the rear of the piston 3 (i.e. rear face 41a of the plate 40) than the area at the front of the piston 3 (i.e. the face 4 of the shaft 7 and beveled portion 5 of the shaft 7), it may be seen that as pressure builds behind the rear face 41a of the piston plate 40 due to introduction of a pressurized fluid into the rear pressure chamber 8a, the pressure to force piston 3 rearward (and thereby regulate flow through the regulator 2) will increase.
To further overcome the pressure exerted at the rear face 41a of the plate 40 by the pressurized fluid introduced into the rear chamber 8a, the user may selectively introduce pressurized fluid into the forward pressure chamber 8b from the same pressurized fluid source 44 or from a different pressurized fluid source. The pressurized fluid may then exert a force on the forward face 41b of the plate 40 in a direction opposite the force exerted at the rear face 41a of the plate 40. This pressure exerted on the forward face 41b of the piston plate 40 may work with the pressure exerted on the shaft 7 by the fluid flowing in the fluid flow chamber 6 to balance the pressure exerted in the rear pressure chamber 8a. The pressure introduced on either side 8a, 8b of the pressure chamber 8 can be selectively controlled such that flow regulation of the fluid through the fluid flow chamber 6 can be selectively regulated as desired.
In one embodiment, the degree of pressurized fluid introduced into the various sides 8a, 8b of the pressure chamber 8 may be selectively (or automatically) controlled by a controller 80 in communication with a microprocessor. The use of a microprocessor capable of changing rates of the pressurized fluid source several times a second allows for a constant adjustment regulation rate through the regulator 2, allowing for appropriate flow through the regulator 2 within a very tight window. In one embodiment, a pressure switch or transducer may 46 be located in the outlet flow area 24 to provide a signal to the controller 80 (or user, if manual control of pressure is implemented) to modify the pressure introduced into the various sides 8a, 8b of the pressure chamber such that the pressures can be balanced at the desired flow rate, as shown in
In various embodiments, the pressurized air supply lines 54a, 54b may each include a valve 78a, 78b for selective operation of the air supply line 54a, 54b, allowing the user to selectively control the introduction of pressurized air into each pressure chamber 8a, 8b of the regulator 2. The valves 78a, 78b may also include vents 42a, 42b, allowing pressurized air to be released through the valve 78a, 78b, which may, for example, be useful for bleeding air from the supply hose or releasing air from the portion 8a, 8b of the pressure chamber 8 fluidically connected to that particular air supply line 54a, 54b and valve 78a, 78b. By independently controlling each air supply line 54a, 54b and valve 78a, 78b to either its supply position (wherein pressurized air is introduced through the line into the pressure chamber 8a, 8b) or its vent position (wherein pressurized air is vented from the pressure chamber 8a, 8b through the air supply line 54a, 54b and valve 78a, 78b), various modes of operation of the regulator 2 may be selectively achieved as desired by the user.
For example, in a first mode configuration, as shown in
In a third mode configuration, as shown generally in
In one embodiment, the valve 78b on the forward pressure chamber supply line 54b is controlled by a cylinder 88, lever 86, and spring 90 assembly, as shown in FIGS. 10-12. The cylinder 88 comprises a piston that is inside a chamber fluidically connected to the flow outlet area 24 (i.e. the pump inlet area 64), such that change in pressure at the flow outlet area/pump inlet area 24/64 modifies the valve 78b based on movement of the cylinder 88 and lever 86 of the valve controlling assembly. The cylinder 88 and lever 86 move in various directions depending on the pressure exerted on the cylinder 88 by the liquid moving through a fluidic line 92 to the cylinder 88 from the pump inlet area 64. For example, as shown in
All terms used herein should be interpreted in the broadest possible manner consistent with the context. When a grouping is used herein, all individual members of the group and all combinations and subcombinations possible of the group are intended to be individually included in the disclosure. All references cited herein are hereby incorporated by reference to the extent that there is no inconsistency with the disclosure of this specification. If a range is expressed herein, such range is intended to encompass and disclose all sub-ranges within that range and all particular points within that range.
The present invention has been described with reference to certain embodiment(s) that are intended to be exemplary only and not limiting to the full scope of the present invention as set forth in the following claims.
This application is a continuation-in-part of U.S. patent application Ser. No. 15/714,276, filed on Sep. 25, 2017, and entitled “Pressure Regulating Valve with Incorporated Shut-Off Mechanism and Fluidic Bypass”, which is a continuation-in-part of (a) allowed U.S. patent application Ser. No. 15/206,037, filed on Jul. 08, 2016, and entitled “Dual-Piston Pressure Reducer”, which claims priority to U.S. Provisional Patent Application No. 62/190,630 and has issued into U.S. Pat. No. 9,891,635 and (b) U.S. patent application Ser. No. 15/493,415, filed on Apr. 21, 2017, and entitled “Pressure Reducing Valve with Incorporated Shut-Off Mechanism”, which claims priority to U.S. Provisional Patent Nos. 62/190,630, 62/326,056, and 62/333,451. This application is also a continuation-in-part of U.S. patent application Ser. No. 15/714,406, filed on Sep. 25, 2017, and entitled “Pressure Regulating Valve with Multi-Pronged Piston Assembly,” which is also a continuation-in-part of U.S. patent application Ser. No. 15/206,037 and U.S. patent application Ser. No. 15/493,415. All of such applications are incorporated by reference herein in their entireties.
| Number | Date | Country | |
|---|---|---|---|
| 62190630 | Jul 2015 | US | |
| 62190630 | Jul 2015 | US | |
| 62326056 | Apr 2016 | US | |
| 62333451 | May 2016 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15714276 | Sep 2017 | US |
| Child | 16266746 | US | |
| Parent | 15206037 | Jul 2016 | US |
| Child | 15714276 | US | |
| Parent | 15493415 | Apr 2017 | US |
| Child | 15206037 | US | |
| Parent | 15714406 | Sep 2017 | US |
| Child | 15493415 | US | |
| Parent | 15206037 | Jul 2016 | US |
| Child | 15714406 | US | |
| Parent | 15493415 | Apr 2017 | US |
| Child | 15206037 | US |
