Fluid flow controlling valve having seal with reduced leakage

A valve for controlling fluid flow comprising:

• (a) a housing comprising (i) a base with first, second and third ports;
• and (ii) a cover fitting over the base, the cover comprising a chamber with a fourth port;
• (b) a movable element comprising a movable surface having an opening and a channel capable of connecting one or more of the first, second, third or fourth ports, the movable element capable of moving between (i) a first position in which the opening is aligned to at least one of the first, second, or third ports such that fluid can pass between at least two of the first, second, and third ports, via the channel, and (ii) a second position which blocks the passage of fluid between the first, second and third ports;
• (c) at least one rim seal encircling each of the first, second and third ports of the housing, each opening in the movable surface, or both;
• and
• (d) a floating seal between the movable surface of the movable element and the housing, the floating seal being in contact with the at least one rim seal, the floating seal comprising:
• (i) a passage that aligns with the movable surface opening and any of the first, second or third ports, when the movable element is in the first position;
• and
• (ii) a continuous sealing surface about the passage that is sufficiently long to close off the opening of the movable surface as the movable element moves from the first position to the second position thereby reducing leakage of fluid between the opening of the movable surface and the first, second or third ports.

A method of controlling a fluid flow path between first and second ports comprising:

• (a) aligning an opening to a first position in which the opening is aligned to at least one of the first and second ports to allow fluid to pass between the ports;
• (b) moving the opening from the first position to a second position in which the ports are blocked to prevent fluid from passing between the ports;
• and
• (c) during (b), covering the opening with a continuous sealing surface while moving the opening from the first position to the second position to reduce leakage of fluid between the opening and the first and second ports.

A fluid treatment apparatus comprising:

• (a) a pair of electrochemical cells, each cell comprising:
• (i) a housing comprising a pair of electrodes;
• (ii) a water-splitting ion exchange membrane between the electrodes;
• and
• (iii) a fluid inlet and a fluid outlet;
• (b) a power supply to supply a current to the electrodes;
• (c) a valve comprising:
• (i) a housing comprising (1) a base with first, second, and third ports;
• and (2) a cover fitting over the base, the cover comprising a chamber with a fourth port;
• (ii) a movable element comprising a movable surface having an opening and a channel capable of connecting one or more of the first, second, third or fourth ports, the movable element capable of moving between (i) a first position in which the opening is aligned to at least one of the first, second, or third ports such that fluid can pass between at least two of the first, second and third ports via the channel, and (ii) a second position which blocks the passage of fluid between the first, second and third ports;
• (iii) at least one rim seal encircling each of the first, second and third ports of the housing, each opening in the movable surface, or both;
• (iv) a motor connected to the movable element;
• and
• (v) a floating seal between the movable surface of the movable element and the housing, the floating seal being in contact with the at least one rim seal, the floating seal comprising:
• (1) a passage that aligns with the movable surface opening and any of the first, second or third ports, when the movable element is in the first position;
• and
• (2) a continuous sealing surface about the passage that is sufficiently long to close off the opening of the movable surface as the movable element moves from the first position to the second position thereby reducing leakage of fluid between the opening and the first, second or third ports;
• and
• (d) a valve controller capable of operating the motor to move the movable element from the first position to the second position.

A rotary valve for controlling fluid flow comprising:

• (a) a housing comprising a first port and a second port, and at least one rim seal encircling each of the first and second ports;
• (b) a rotor comprising a movable surface having an opening, the rotor capable of moving between (i) a first position in which the opening of the movable surface is aligned to at least one of the first or second ports such that fluid can pass between the first and second ports, and (ii) a second position which blocks the passage of fluid between the first and second ports;
• (c) a floating seal between the movable surface of the rotor and the at least one rim seals, the floating seal comprising:
• (i) a passage that aligns with the movable surface opening and at least one of the first and second ports when the rotor is in the first position;
• and
• (ii) a continuous sealing surface about the passage that is sufficiently long to close off the opening of the movable surface as the rotor moves from the first position to the second position thereby reducing leakage of fluid between the opening of the movable surface and the first and second ports;
• and
• (d) a rotary actuator to rotate the rotor between the first position and the second position.

A sliding valve for controlling fluid flow comprising:

• (a) a housing comprising a first port and a second port, and at least one rim seal encircling each of the first and second ports;
• (b) a sliding member comprising a movable surface having an opening, the sliding member capable of sliding between (i) a first position in which the opening of the movable surface is aligned to at least one of the first or second ports such that fluid can pass between the first and second ports, and (ii) a second position which blocks the passage of fluid between the opening of the movable surface and the first and second ports;
• (c) a floating seal between the movable surface of the sliding member and the at least one rim seals, the floating seal comprising:
• (i) a passage that aligns with the sliding member opening and at least one of the first and second ports when the sliding member is in the first position;
• and
• (ii) a continuous sealing surface about the passage that is sufficiently long to close off the opening of the movable surface as the sliding member slides from the first position to the second position thereby reducing leakage of fluid between the opening of the movable surface and first and second ports;
• and
• (d) a linear actuator to slide the sliding member between the first and second positions.

A cylinder valve for controlling fluid flow comprising:

• (a) a cylindrical housing comprising a first port and a second port;
• (b) a cylindrical rotating member comprising a sidewall having a movable surface and an opening and at least one rim seal encircling the opening, the cylindrical rotating member capable of rotating between (i) a first position in which the opening of the movable surface is aligned to the first or second ports such that fluid can pass between ports, and (ii) a second position which blocks the passage of fluid between the first and second ports;
• (d) a floating seal between the cylindrical housing and the at least one rim seal, the floating seal comprising:
• (i) a passage that aligns with the movable surface opening and at least one of the first and second ports when the cylindrical rotating member is in the first position;
• and
• (ii) a continuous sealing surface about the passage that is sufficiently long to close off the opening of the movable surface as the cylindrical rotating member rotates from the first position to the second position thereby reducing leakage of fluid between the movable surface opening and the first and second ports;
• and
• (e) a rotary actuator to rotate the cylindrical rotating member between the first and second positions.

A fluid treatment apparatus comprising:

• (a) an electrochemical cell comprising first and second orifices to receive or expel a fluid, a pair of electrodes, and at least one water-splitting ion exchange membrane between the electrodes;
• (b) a power supply to supply a current to the electrodes of the cell;
• (c) a valve to control fluid flow through the cell;
• and
• (d) a controller to operate the power supply and valve to:
• (i) in a deionization mode, flow fluid into the first orifice of the cell while maintaining a current between the electrodes in the cell to form a treated fluid which is passed out of the second orifice of the cell;
• and
• (ii) in a regeneration mode, flow fluid into the second orifice of the cell while maintaining a current between the electrodes of the cell to regenerate the cell.

A fluid treatment apparatus comprising:

• (a) first and second electrochemical cells, each electrochemical cell comprising a pair of orifices to receive or expel a fluid, a pair of electrodes, and at least one water-splitting ion exchange membrane between the electrodes;
• (b) a power supply to supply a current to the electrodes of the first and second cells;
• (c) a valve to control fluid flow through the first and second cells;
• and
• (d) a controller to operate the power supply and valve to:
• (i) deionize fluid in the first cell by maintaining a current between the electrodes of the first cell while flowing fluid into the first cell to form treated fluid which is released at an orifice of the first cell, and
• (ii) regenerate the second cell by flowing the treated fluid from the orifice of the first cell into an orifice of the second cell while maintaining a current between the electrodes of the second cell to regenerate the second cell.

A fluid treatment apparatus comprising:

• (a) first and second electrochemical cells, each electrochemical cell comprising a first orifice to receive a fluid for deionization and a second orifice to expel the deionized fluid, a pair of electrodes, and at least one water-splitting ion exchange membrane between the electrodes;
• (b) a power supply to supply a current to the electrodes of the first and second cells;
• (c) a valve to control fluid flow through the first and second orifices of the first and second cells;
• and
• (d) a controller to operate the power supply and valve to:
• (i) deionize fluid in the first cell by maintaining a current between the electrodes of the first cell while flowing fluid into the first orifice of the first cell to form deionized fluid which is released at the second orifice of the first cell, and
• (ii) regenerate the second cell by flowing the deionized fluid from the second orifice of the first cell into the second orifice of the second cell while maintaining a current between the electrodes of the second cell to regenerate the second cell.