The embodiments described below relate to variable flow rate valves and, more particularly, to a dual orifice variable flow rate valve.
Valves are used to control fluid flow rates for various applications. For example, a variable flow rate valve can receive a fluid from a fluid supply at a given pressure and supply the fluid at a desired flow rate. This is typically done with a valve member that moves relative to a fixed orifice in a valve body. The valve member can be moved by, for example, a solenoid. In valves with solenoids, an electric current is supplied to a coil that is disposed proximate to the valve member. The coil generates a magnetic field that applies a magnetic force on the valve member, which moves the valve member.
Sometimes variable fluid flow rate valves are unable to meet flow rate specifications. For example, some applications may require accurate proportional control at both high and low flow rates. That is, the current supplied to the valve may need to linearly correspond with the fluid flow rate at both the high and low flow rates. However, the current supplied to the valve may not correspond to an expected fluid flow rate. For example, the fluid flow rate can have a linear correlation at low fluid flow rates but be non-linear at higher fluid flow rates. This can be due to many factors, such as valve member movements that are small relative to the large valve member displacements that correspond to high fluid flow rates.
Proportional control at a high fluid flow rate can be accomplished with a large orifice. However, the large orifice can lead to non-proportional fluid flow rate control at lower flow rates. For example, to achieve the lower flow rates, the valve member may be relatively close to the orifice, which causes the fluid flow rate to be non-proportional to the current in the solenoid. Proportional control can be accomplished with complex solenoid designs or sophisticated control systems, however such designs are prohibitively expensive and prone to failure.
Accordingly, there is a need for an inexpensive solution for applications that are able to meet flow rate specifications at both high and low flow rates, which is provided by a dual orifice variable flow rate valve.
A dual orifice variable flow rate valve is provided. According to an embodiment, the dual orifice variable flow rate valve comprises a valve body with a first fluid port and a second fluid port, the first fluid port having a first fluid orifice. The dual orifice variable flow rate valve further comprises a dual valve member disposed in the valve body, the dual valve member being comprised of a first valve member disposed in the valve body, the first valve member having a second fluid orifice fluidly coupled to the first fluid port and a first distal end proximate the first fluid orifice and a second valve member disposed in the valve body proximate the second fluid orifice in the first valve member. The dual orifice variable flow rate valve further comprises an actuator configured to move the second valve member relative to the first valve member to control a fluid flow between the first fluid port and the second fluid port through the second fluid orifice in the first valve member.
A method of controlling a fluid flow through a dual orifice variable flow rate valve comprised of a first fluid port and a second fluid port is provided. According to an embodiment, the method comprises providing a first valve member and a second valve member, fluidly coupling the first fluid port and the second fluid port through a second fluid orifice in the first valve member by moving the second valve member, and fluidly coupling the first fluid port and the second fluid port through a second fluid orifice by moving the first valve member with the second valve member.
According to an aspect, a dual orifice variable flow rate valve (100, 700, 900) comprises a valve body (110, 710, 910) with a first fluid port (112, 712, 912) and a second fluid port (114, 714, 914), the first fluid port (112, 712, 912) having a first fluid orifice (112a, 712a, 912a), a dual valve member (120, 720, 920) disposed in the valve body (110, 710, 910), the dual valve member (120, 720, 920) is comprised of a first valve member (122, 722, 922) disposed in the valve body (110, 710, 910), the first valve member (122, 722, 922) having a second fluid orifice (122e, 722e, 922e) fluidly coupled to the first fluid port (112, 712, 912) and a first distal end (122a, 722a, 922a) proximate the first fluid orifice (112a, 712a, 912a) and a second valve member (124, 724, 924) disposed in the valve body (110, 710, 910) proximate the second fluid orifice (122e, 722e, 922e) in the first valve member (122, 722, 922). The dual orifice variable flow rate valve (100) also comprises an actuator (130, 730, 930) configured to move the second valve member (124, 724, 924) relative to the first valve member (122, 722, 922) to control a fluid flow between the first fluid port (112, 712, 912) and the second fluid port (114, 714, 914) through the second fluid orifice (122e, 722e, 922e) in the first valve member (122, 722, 922).
Preferably, the actuator (130, 730, 930) is further configured to move the second valve member (124, 724, 924) to control a fluid flow rate between the first fluid port (112, 712, 912) and the second fluid port (114, 714, 914) through the first fluid orifice (112a, 712a, 912a).
Preferably, the second valve member (124, 724, 924) further comprises a sealing end (124b, 724b, 924b) that selectively engages the first valve member (122, 722, 922).
Preferably, the sealing end (124b, 724b, 924b) is disposed inside the first valve member (122, 722, 922) and is adapted to contact a surface inside the first valve member (122, 722, 922).
Preferably, the second valve member (124, 724, 924) further comprises an armature end (124a, 724a, 924a) that selectively engages a diaphragm (140, 740, 940) to limit a stroke length of the second valve member (124, 724, 924).
Preferably, the first valve member (122, 722, 922) and the second valve member (124, 724, 924) move along an axis (X-X) of the dual orifice variable flow rate valve (100, 700, 900).
Preferably, the second valve member (124, 724, 924) moves along the axis (X-X) at a second stroke length that corresponds with the fluid flow rate between the first fluid port (112, 712, 912) and the second fluid port (114, 714, 914) via the conduit in the first valve member (122, 722, 922).
Preferably, the dual orifice variable flow rate valve further comprises a plurality of conduits (922c) concentrically disposed about the axis (X).
According to an aspect, a method of controlling a fluid flow through a dual orifice variable flow rate valve (100, 700, 900) comprised of a first fluid port (112, 712, 912) and a second fluid port (114, 714, 914) comprises providing a first valve member (122, 722, 922) and a second valve member (124, 724, 924), fluidly coupling the first fluid port (112, 712, 912) and the second fluid port (114, 714, 914) through a second fluid orifice (122e, 722e, 922e) in the first valve member (122, 722, 922) by moving the second valve member (124, 724, 924), and fluidly coupling the first fluid port (112, 712, 912) and the second fluid port (114, 714, 914) through a first fluid orifice (112a, 712a, 912a) by moving the first valve member (122, 722, 922) with the second valve member (124, 724, 924).
Preferably, the method further comprises flowing fluid through the second fluid orifice (122e, 722e, 922e) at a first fluid flow rate that corresponds to a displacement distance of the second valve member (124, 724, 924) and flowing fluid through the first fluid orifice (112a, 712a, 912a) at a second fluid flow rate that corresponds to a displacement distance of the first valve member (122, 722, 922).
Preferably, the method further comprises controlling the fluid flow rate through the second fluid orifice (122e, 722e, 922e) and the first fluid orifice (112a, 712a, 912a) with a current in an actuator (130, 730, 930) that applies a magnetic force to the second valve member (124, 724, 924).
Preferably, the method further comprises selectively engaging a sealing end (124b, 724b, 924b) of the second valve member (124, 724, 924) with the first valve member (122, 722, 922) to move the first valve member (122, 722, 922).
Preferably, selectively engaging comprises contacting a surface in the first valve member (122, 722, 922) with the sealing end (124b, 724b, 924b).
Preferably, the method further comprises selectively engaging an armature end (124a, 724a, 924a) on the second valve member (124, 724, 924) with a diaphragm to limit a stroke length of the second valve member (124, 724, 924).
Preferably, the method further comprising moving the first valve member (122, 722, 922) and the second valve member (124, 724, 924) along an axis (X-X) to fluidly couple the first fluid port (112, 712, 912) and the second fluid port (114, 714, 914).
Preferably, the method further comprises displacing the second valve member (124, 724, 924) away from the second fluid orifice (122e, 722e, 922e) wherein the second fluid orifice (122e, 722e, 922e) is in the first valve member (122, 722, 922).
The same reference number represents the same element on all drawings. It should be understood that the drawings are not necessarily to scale.
The first fluid port 112 and the second fluid port 114 may be fluidly coupled to conduits (not shown) that carry a fluid. For example, according to an embodiment, a supply conduit can be coupled to the first fluid port 112 and a load conduit can be fluidly coupled to the second fluid port 114. The load conduit can carry pressurized fluid that is controlled by the dual orifice variable flow rate valve 100. The fluid controlled by the dual orifice variable flow rate valve 100 can be supplied via the second fluid port 114. In alternative embodiments, the supply conduit can be coupled to the second fluid port 114 and the load conduit can be coupled to the first fluid port 112. For example, the second fluid port 114 could be an inlet and the first fluid port 112 can be the outlet. The fluid controlled by the dual orifice variable flow rate valve 100 can be used to, for example, operate actuators, control valves, or the like.
The inner o-ring 113 and the outer o-ring 115 can fluidly seal the first fluid port 112 and the second fluid port 114 to ensure that the pressurized fluid provided by the conduits do not leak. For example, the inner o-ring 113 can prevent the fluid carried by the supply conduit to the first fluid port 112 does not leak past the inner o-ring 113 and into the fluid carried by the load conduit from the second fluid port 114. The o-rings 113, 115 can be comprised of a flexible material such as neoprene although any suitable material can be used. In alternative embodiments, the o-rings 113, 115 may be any appropriate sealing means or may not be employed.
The valve body 110, dual valve member 120, actuator 130, and diaphragm 140 are shown as concentrically disposed around the axis X-X. However, in alternative embodiments, the valve body 110, dual valve member 120, actuator 130, and diaphragm 140 may not be concentrically disposed around the axis X-X. For example, the dual valve member 120 and the actuator 130 could be offset from an axis of an alternative embodiment of the valve body 110. Additionally or alternatively, the diaphragm 140 could have an asymmetric shape that is not coaxial to an axis of the valve body 110.
In the embodiment shown, the valve body 110 can be formed by press fitting the inner body 110b into the outer body 110a. For example, the inner body 110b can be formed with the first fluid port 112 and the second fluid port 114 prior to the inner body 110b being inserted into the outer body 110a. Subsequently, the inner body 110b can be inserted into the outer body 110a with an interference fit. This may reduce the costs associated with fabricating the valve body 110 relative to other embodiments of the valve body 110. However, in alternative embodiments, the valve body 110 can be formed by other methods and have any appropriate shape. For example, alternative valve bodies can be formed by casting the valve body and have a non-cylindrical shape. In the embodiment shown, the fluid ports 112, 114 formed in the valve body 110 can be fluidly coupled with the dual valve member 120.
The dual valve member 120 can be comprised of valve members, such as those described in the following with reference to
The actuator 130 is shown as having a cylindrical shape with a first distal end 130a that is oriented towards the first fluid port 112 and a second distal end 130b that is oriented towards the signal line 118. However, the actuator 130 can have any appropriate shapes and orientations. In the embodiment shown, the actuator 130 is a cylindrical solenoid although any suitable actuator can be employed. For example, the actuator 130 could be a shape memory alloy element that is coupled to the dual valve member 120. The actuator 130 receives an electrical signal from the signal line 118 and provides a magnetic field that moves the dual valve member 120, as described in more detail in the following with reference to
In the embodiment shown, the diaphragm 140 is disposed proximate to the first distal end 130a and in contact with the actuator 130. The diaphragm 140 can prevent fluid inside the valve body 110 from reaching the actuator 130. In alternative embodiments, the diaphragm 140 may not be in contact with the actuator 130 or may not be employed. As shown in
With respect to the dual valve member 120, the first valve member 122 is disposed with a first distal end 122a that is proximate a first fluid orifice 112a on the first fluid port 112. A second distal end 122b is in is proximate to the second valve member 124. A conduit 122c in the first valve member 122 is also shown as proximate the first fluid orifice 112a. The conduit 122c is also fluidly coupled to the first fluid port 112 via the first fluid orifice 112a. The second valve member 124 is shown with an armature end 124a and a sealing end 124b. A spring 124c couples the second valve member 124 to the valve body 110. In the embodiment shown, both the first and second valve members 122, 124 can move along the axis X-X. The first and second valve members 122, 124 can also provide fluid seals, as will be described in more detail in the following.
As can be seen in
In the position shown in
As can also be seen, the sealing end 124b is shown as disposed in the second distal end 122b. However, in alternative embodiments, the sealing end 124b may not be disposed in the second distal end 122b. For example, in alternative embodiments, the sealing end could be disposed around the second distal end. The sealing end 124b also includes a sealing surface 124s that can be pressed against the second fluid orifice 122e. Alternative embodiments may not include the sealing surface. In the embodiment shown in
Parameters of the dual valve member 120, such as dimensions of the fluid orifices 112a, 122e can correspond to flow rates. For example, a diameter of the second fluid orifice 122e can correspond to a first fluid flow rate when flowing through the conduit 122c due to the second valve member 124 being displaced away from the second fluid orifice 122e. Referring now to
The first and second fluid flow rates can also correspond to the displacement of the first valve member 122 and the second valve member 124. For example, the displacement of the second valve member 124 from the second fluid orifice 122e can correspond to the first fluid flow rate. The greater the displacement of the second valve member 124 from the second fluid orifice 122e, the greater the first fluid flow rate. The displacement of the first valve member 122 from the first fluid orifice 112a can correspond to the second fluid flow rate. The greater the displacement of the first valve member 122 from the first fluid orifice 112a, the greater the second fluid flow rate. The displacement of the valve members 122, 124 can be controlled by the actuator 130, as will be described in more detail in the following.
The second valve member 124 can be displaced away from the second fluid orifice 122e with a magnetic field from the actuator 130. For example, the actuator 130 can generate a magnetic field that applies a magnetic force to the second valve member 124. The magnetic force may be directed towards the actuator 130 although other directions can be employed in other embodiments. The magnetic force can be sufficient to move the second valve member 124 relative to the first valve member 122. For example, the magnetic force may be greater than force applied by the spring 124c to the second valve member 124. In the embodiment shown, the actuator 130 can move, with the magnetic field, the second valve member 124 relative to the first valve member 122 to control the fluid flow rate through the conduit 122c.
As can be appreciated from
The magnetic force can correspond to the electric current provided by the signal line 118 to the actuator 130. For example, the signal line 118 can provide a current to the actuator 130. The actuator 130 may receive the current and generate the magnetic field with coils in the actuator 130. The strength of the magnetic field can be proportional to, for example, the amps of the current provided by the signal line 118. The magnetic force can therefore be controlled by controlling the current. In alternative embodiments, the force applied to the second valve member 124 may be due to, for example, a shaped memory alloy (SMA) element coupled to the second valve member 124. In these embodiments, the force applied to the second valve member 124 may be proportional to the current applied to the SMA. In the embodiment shown, the first valve member 122 and the second valve member 124 are displaced by the magnetic force.
In addition to displacing the valve members 122, 124 to the fully open positions shown in
As shown, the flow rate 610 through the dual orifice variable flow rate valve 100 is proportional to the current provided by the signal line 118. The flow rate 610 has a first stage 610a, a second stage 610b, and a third stage 610c. The first stage 610a is shown as being zero for the embodiments described in the foregoing. The first stage 610a may be zero due to the first valve member 122 being in contact with the inner body 110b and the second valve member 124 being in contact with the first valve member 122, which can prevent fluid flow. In alternative embodiments, the first stage 610a can have a non-zero value. As can also be appreciated by the first stage 610a, the fluid flow rate remains zero when the current is between 0 and a first current C1.
The second stage 610b is between the first current C1 and a second current C2. The second stage 610b can increase from zero to a first flow rate Q1 at the second current C2. The first flow rate Q1 may be proportional to the size of the second fluid orifice 122e. The first flow rate Q1 can also be proportional to the distance that the second valve member 124 is displaced from the second fluid orifice 122e. The second stage 610b has a linear slope although any fluid flow with any suitable slope can be employed. In the embodiment shown, the second stage 610b increases linearly from the first current C1-l to the second current C2 in proportion to the current supplied by the signal line 118 to the actuator 130.
The flow rate 610 can have a third stage 610c between the second current C2 and a third current C3. In the third stage 610c, the flow rate 610 can have a linear slope although other slopes may be employed in alternative embodiments. In the embodiment shown, the third stage increases linearly from the second current C2 to the third current C3 in proportion to the current supplied by the signal line 118 to the actuator 130. The slope of the third stage 610c can be proportional to the current supplied by the signal line 118 to the actuator 130. As shown, the slope of the third stage 610c is greater than the slope of the second stage 610b. The slope of the third stage 610c can be greater than the slope of the second stage 610b due to the size of the second fluid orifice 122e being smaller than the size of the first fluid orifice 112a, as shown in the embodiments of
As can be appreciated, the flow rate increases in proportion to the current due to the magnetic force applied to the second valve member 124 by the actuator 130. For example, as the current supplied by the signal line 118 to the actuator 130 increases, the magnetic field of the actuator 130 increases. This increases the magnetic force applied to the second valve member 124. The first current C1 corresponds to when the magnetic forces along the axis X-X are balanced with other forces along the axis X-X on the second valve member 124. As the current increases from the first current C1 to the second current C2, the distance between the second valve member 124 and the second fluid orifice 122e increases. Accordingly, the flow rate increases from zero to the first flow rate Q1. The first flow rate Q1 corresponds to the position shown in
As the current increases from the second current C2 to the third current C3, the flow rate increases from the first flow rate Q1 to the second flow rate Q2. This increase in flow rate from the first flow rate Q1 to the second flow rate Q2 can be due to the actuator 130 moving the first valve member 122 away from the inner body 110b. The current provided to the actuator 130 can vary to increase the magnetic force applied to the second valve member 124. The magnetic force displaces the second valve member 124 away from the inner body 110b and the first fluid orifice 112a. Since the size of the first fluid orifice 112a is larger than the size of the second fluid orifice 122e, the slope of the third stage 610c is greater than the slope of the second stage 610b. The second flow rate Q2 corresponds to the position shown in
The first and the second flow rates Q1, Q2 can correspond to stroke lengths of the first valve member 122. For example, a first stroke length may be the distance between the sealing end 124b and the second fluid orifice 122e at the position shown in
The slope of the second stage 610b and the third stage 610c can correspond to parameters of the dual valve member 120. For example, the spring 124c can have a spring constant that corresponds to the current required to move the second valve member 124 along both the first and second stroke lengths. In the embodiment shown, the greater the spring constant, the more current that may be required to move the dual valve member 120 along the first and second stroke lengths. Other parameters, such as the mass and dimensions of the first valve member 122 and the second valve member 124 as well as fluid properties, can also cause alternative fluid flow rates to have different slopes, shapes, and fluid flow rates in alternative embodiments. For example, alternative embodiments, such as those described in the following, may not include the spring 124c and, instead, have springs coupled to different portions of the dual valve member 120.
The first valve member 722 is disposed with a first distal end 722a that is proximate a first fluid orifice 712a on the first fluid port 712. A conduit 722c in the first valve member 722 is also shown as proximate the first fluid orifice 712a. The conduit 722c is also fluidly coupled to the first fluid port 712 via the first fluid orifice 712a. A second fluid orifice 722e is shown in conduit 722c. The first valve member 722 is movably coupled to the second valve member 724 with a first spring 722f and the second valve member 724 is movably coupled to the valve body 710 with a second spring 722g. The second valve member 724 is shown with an armature end 724a and a sealing end 724b. In the embodiment shown, the first valve member 722 can move along the axis X-X.
The first valve member 922 is disposed with a first distal end 922a that is proximate a fluid orifice 912a on the first fluid port 912. A plurality of conduits 922c (two are shown) in the first valve member 922 are also shown as proximate the fluid orifice 912a and concentrically disposed about the axis X-X. The plurality of conduits 922c is also fluidly coupled to the first fluid port 912 via the fluid orifice 912a. As can be appreciated, the plurality of conduits 922c have a cumulatively larger opening than a second fluid orifice 922e in the first valve member 922. The first valve member 922 is movably coupled to the second valve member 924 with a membrane 922f and the second valve member 924 is movably coupled to the valve body 910 with a spring 924c. The membrane 922f can be comprised of flexible material that, for example, allows fluid pressures within the valve body 910 to balance. The second valve member 924 is shown with an armature end 924a and a sealing end 924b. In the embodiment shown, the first valve member 922 can move along the axis X-X.
The embodiments described above provide a dual orifice variable flow rate valve 100, 700, 900. As explained in the foregoing, the dual orifice variable flow rate valve 100, 700, 900 control a fluid flow between the first fluid port 112, 712, 912 and the second fluid port 114, 714, 914. For example, the dual orifice variable flow rate valve 100, 700, 900 can control a fluid flow rate of the fluid flow. The fluid flow rate can be proportional to more than one orifice, such as the second fluid orifice 122e, 722e, 922e and the first fluid orifice 112a, 712a, 912a.
The second fluid orifice 122e, 722e, 922e can be formed in the first valve member 122, 722, 922 and have a dimension that corresponds to a first fluid flow rate Q1. The first fluid port 112, 712, 912 can be formed in the inner body 110b, 710b, 910b and have a dimension that corresponds to a second fluid flow rate Q2. For example, the second fluid flow rate Q2 can correspond to a dimension, such as the diameter, of the first fluid orifice 112a, 712a, 912a. The first and second fluid flow rates Q1, Q2 can be maximum fluid flow rates for fully displaced first valve member 122, 722, 922 and second valve member 124, 724, 924.
The displacement of the first valve member 122, 722, 922 and the second valve member 124, 724, 924 can be controlled by the actuator 130, 730, 930. For example, the current in the actuator 130, 730, 930 can be proportional to a displacement distance of the dual valve member 120, 720, 920. In the embodiments described in the foregoing, the current can be proportional to the displacement distance of the first valve member 122, 722, 922. The current can also be proportional to the displacement distance of the second valve member 124, 724, 924.
The displacement distance of the dual valve member 120, 720, 920 can correspond with the fluid flow rate through the dual orifice variable flow rate valve 100, 700, 900. For example, the fluid flow rate can correspond with the displacement distance of the first valve member 122, 722, 922. That is, the further the first valve member is displaced from the first fluid orifice 112a, 712a, 912a, the greater the fluid flow rate. Similarly, the fluid flow rate can correspond to the displacement distance of the second valve member 124, 724, 924. That is, the further the second valve member 124, 724, 924 is displaced away from the second fluid orifice 122e, 722e, 922e, the greater the fluid flow through the dual orifice variable flow rate valve 100, 700, 900.
As explained in the foregoing, the actuator 130, 730, 930 can control the fluid flow rate through the dual orifice variable flow rate valve 100, 700, 900 in proportion to the current. For example, the actuator 130, 730, 930 can move the second valve member 124, 724, 924 away from the second fluid orifice 122e, 722e, 922e in the first valve member 122, 722, 922 along the first stroke length. Accordingly, the flow rate through the dual valve member 120, 720, 920 can be in proportion to the current and the dimensions of the second fluid orifice 122e, 722e, 922e. In the second stroke length, the second valve member 124, 724, 924 contacts the first valve member 122, 722, 922 and displaces the first valve member 122, 722, 922 away from the first fluid orifice 112a, 712a, 912a. Accordingly, the fluid flow rate through the dual orifice variable flow rate valve 100, 700, 900 can be proportional to the current and the dimensions of the first fluid orifice 112a, 712a, 912a. The fluid flow through the dual orifice variable flow rate valve 100, 700, 900 can therefore be proportional to a dimension in more than one orifice and vary in proportion to the current.
The detailed descriptions of the above embodiments are not exhaustive descriptions of all embodiments contemplated by the inventors to be within the scope of the present description. Indeed, persons skilled in the art will recognize that certain elements of the above-described embodiments may variously be combined or eliminated to create further embodiments, and such further embodiments fall within the scope and teachings of the present description. It will also be apparent to those of ordinary skill in the art that the above-described embodiments may be combined in whole or in part to create additional embodiments within the scope and teachings of the present description.
Thus, although specific embodiments are described herein for illustrative purposes, various equivalent modifications are possible within the scope of the present description, as those skilled in the relevant art will recognize. The teachings provided herein can be applied to other dual orifice variable flow rate valve, and not just to the embodiments described above and shown in the accompanying figures. Accordingly, the scope of the embodiments described above should be determined from the following claims.
Number | Date | Country | Kind |
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14/56641 | Jul 2014 | FR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2015/065808 | 7/10/2015 | WO | 00 |