Patent Description:
The present disclosure relates to valves, and more particularly to magnetically actuated valves. A magnetically actuated valve is disclosed in the document <CIT>.

The invention is defined by a pneumatic valve in accordance with claim <NUM>. The present disclosure provides, in one aspect, a pneumatic valve including a housing with a first port, a second port, and a third port, and a first valve element including a first magnet. The first valve element is movable between an open position and a closed position, and the first valve element is configured to seal the first port in the closed position. The pneumatic valve further includes a second valve element including a second magnet. The second valve element is movable between an open position and a closed position, and the second valve element is configured to seal the third port in the closed position. The pneumatic valve also includes a magnetic actuating element rotatable between a first position and a second position. The first valve element and the second valve element are movable between the open position and the closed position in response to rotation of the magnetic actuating element between the first position and the second position.

The present disclosure provides, in another aspect, a pneumatic valve including a housing with a port and a valve element with a magnet. The valve element is movable between an open position in which the valve element is spaced from the port and a closed position in which the valve element seals the port. The pneumatic valve also includes a magnetic actuating element rotatable between a first position and a second position. The valve element is movable from the closed position toward the open position in response to rotation of the magnetic actuating element from the first position to the second position.

The present disclosure provides, in another aspect, a pneumatic valve including a housing with a port and a valve element with a magnet. The valve element is movable between an open position in which the valve element is spaced from the port and a closed position in which the valve element seals the port. The pneumatic valve also includes a magnetic actuating element movable between a first position and a second position. The magnetic actuating element is configured to repel the valve element when the magnetic actuating element is in the first position, and the magnetic actuating element is configured to attract the valve element when the magnetic actuating element is in the second position.

Other features and aspects of the disclosure will become apparent by consideration of the following detailed description and accompanying drawings.

Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of supporting other embodiments and of being practiced or of being carried out in various ways. In the following description <NUM> inch corresponds to <NUM>.

<FIG> illustrate a valve <NUM> according to one embodiment of the present disclosure. The illustrated valve <NUM> includes a generally cylindrical housing <NUM> with a first end wall <NUM>, a second end wall <NUM>, and a side wall <NUM> extending between the end walls <NUM>, <NUM> (<FIG>). A plurality of legs <NUM> extends from the side wall <NUM>, which may facilitate mounting the valve <NUM> in various ways. In other embodiments, the housing <NUM> may have other shapes and mounting configurations.

Referring to <FIG>, the walls <NUM>, <NUM>, <NUM> collectively define a cavity <NUM> within the housing <NUM>. An electrically conductive coil <NUM> is coupled to the side wall <NUM> (e.g., in a recess formed in the side wall <NUM>), such that the coil <NUM> is concentrically aligned with the cavity <NUM>. The coil <NUM> may be made of copper, silver, gold, or any other suitable electrically conductive material. A power source (not shown) is electrically coupled to the coil <NUM> so that the power source and the coil <NUM> form a circuit in which the power source is able to drive current through the coil <NUM>. In the illustrated embodiment, the power source is capable of selectively driving current through the coil <NUM> in a first (e.g., positive) direction and a second (e.g., negative) direction. In some embodiments, the direction of current flow through the coil <NUM> may be selectively varied using a positive to negative converter, by selectively electrically coupling two different power sources to the coil <NUM>, or by any other suitable means.

The illustrated valve <NUM> includes three ports: a first port or pressure port <NUM>, a second port or bladder port <NUM>, and a third port or vent port <NUM>. The pressure port <NUM> may be fluidly coupled to a source of pressurized fluid (e.g., an air pump or compressor, not shown). The bladder port <NUM> may be fluidly coupled to a vessel for containing pressurized fluid (e.g., an inflatable bladder; not shown) or to a downstream valve assembly or fluidic switching module configured to route the pressurized air to one or more such vessels. The vent port <NUM> is in fluid communication with the environment surrounding the valve <NUM>. In the illustrated embodiment, the pressure port <NUM> extends from the first end wall <NUM>, the vent port <NUM> extends from the second end wall <NUM>, and the bladder port <NUM> extends from the side wall <NUM>. In some embodiments, the ports <NUM>, <NUM>, <NUM> may extend from different portions of the housing <NUM>, or the ports <NUM>, <NUM>, <NUM> may be recessed into the housing <NUM>. In some embodiments, the ports <NUM>, <NUM>, <NUM> may be configured differently (e.g., the first port <NUM> may be the vent port, and the third port <NUM> may be the pressure port, etc.).

With continued reference to <FIG>, an actuator assembly <NUM> is contained within the cavity <NUM> of the housing <NUM>. The illustrated actuator assembly <NUM> includes a first valve element 50a, a second valve element 50b, and an actuating element <NUM>. Each of the valve elements 50a, 50b includes a permanent magnet <NUM> having a first end <NUM> and a second end <NUM> opposite the first end <NUM>. The first ends <NUM> of the magnets <NUM> face away from the actuating element <NUM>, and the second ends <NUM> of the magnets <NUM> face toward the actuating element <NUM> in the illustrated embodiment. The first end <NUM> has a first magnetic polarity (e.g., north), and the second end <NUM> has a second, opposite magnetic polarity (e.g., south). In the illustrated embodiment, the permanent magnets <NUM> are rare earth magnets made of NdFeB or any other suitable magnetic material. The magnets <NUM> are nickel plated, axially magnetized, and cylindrical in shape, with a diameter of about <NUM>/<NUM>-inch and a thickness of about <NUM>/<NUM>-inch. In other embodiments, the magnets <NUM> may be made with different magnetic materials and formed in different shapes or dimensions.

Each of the valve elements 50a, 50b further includes a seal <NUM> coupled to the first end <NUM> of the magnet <NUM> and a spacer <NUM> coupled to the second end <NUM>. The seal <NUM> of the first valve element 50a is configured to selectively engage and seal the pressure port <NUM>. The seal <NUM> of the second valve element 50b is configured to selectively engage and seal the vent port <NUM>. The spacers <NUM> are made of a material with a low coefficient of friction, such as Teflon® or Delrin®, and are positioned between the magnets <NUM> and the actuating element <NUM>. In the illustrated embodiment, the spacers <NUM> are about <NUM> inches thick; however, the spacers <NUM> may have other thicknesses.

With continued reference to <FIG>, the actuating element <NUM> is located in the cavity <NUM> between the first and second valve elements 50a, 50b and surrounded by the coil <NUM>. In the illustrated embodiment, the actuating element <NUM> is a spherical permanent magnet (e.g., a rare earth magnet such as NeFeB) that is nickel plated and axially magnetized. The actuating element <NUM> has a diameter of <NUM>/<NUM> inch in the illustrated embodiment, but the actuating element <NUM> may be made from different magnetic materials and formed in different shapes or dimensions in other embodiments. For example, in some embodiments, the actuating element <NUM> may be shaped as a cylinder. The actuating element <NUM> includes a first magnetic pole 44a (e.g., a north pole) and a second magnetic pole 44b (e.g., a south pole) opposite the first magnetic pole 44a. In the illustrated embodiment, the first magnetic pole 44a has the same magnetic polarity as the first ends <NUM> of the magnets <NUM>, and the second magnetic pole 44b has the same magnetic polarity as the second ends <NUM> of the magnets <NUM>.

The actuating element <NUM> is rotatable between a first orientation (<FIG>) and a second orientation (<FIG>) in response to the power supply driving current through the coil <NUM> in the first direction and the second direction, respectively. In response to rotation of the actuating element <NUM> between the first orientation and the second orientation, the first valve element 50a is movable between a closed position (<FIG>), in which the seal <NUM> of the first valve element 50a engages and seals the pressure port <NUM>, and an open position (<FIG>), in which the seal <NUM> of the first valve element 50a is spaced from the pressure port <NUM> to allow fluid to flow through the pressure port <NUM>. Likewise, the second valve element 50b is movable between a closed position (<FIG>) in which the seal <NUM> of the second valve element 50b engages and seals the vent port <NUM> and an open position (<FIG>) in which the seal <NUM> of the second valve element 50b is spaced from the vent port <NUM> to allow fluid to flow through the vent port <NUM>. The valve elements 50a, 50b are movable between their respective open and closed positions under the influence of magnetic attraction and repulsion in response to rotation of the actuating element <NUM>.

In operation, to inflate the vessel coupled to the bladder port <NUM>, the power supply is energized to drive current through the coil <NUM> in the first direction, moving the actuating element <NUM> to the first orientation illustrated in <FIG>. In particular, the current traveling through the coil <NUM> produces a magnetic field that acts on the actuating element <NUM> to orient the first magnetic pole 44a toward the first valve element 50a and the second magnetic pole 44b toward the second valve element 50b. The attractive magnetic force between the second end <NUM> of the magnet <NUM> in the first valve element 50a and the first magnetic pole 44a of the actuating element <NUM> draws the first valve element 50a toward the actuating element <NUM>, unsealing the pressure port <NUM>. In the illustrated embodiment, the first valve element 50a is displaced to the open position in which the spacer <NUM> engages the actuating element <NUM>, and the seal <NUM> is spaced from the pressure port <NUM>. Simultaneously, the magnetic repulsive force between the second end <NUM> of the magnet <NUM> in the second valve element 50b and the second magnetic pole 44b of the actuating element <NUM> pushes the second valve element 50b to its closed position so that the seal <NUM> engages and seals the vent port <NUM>.

Thus, in the inflating configuration of the valve <NUM> illustrated in <FIG>, the pressure port <NUM> is open to the chamber <NUM> and the bladder port <NUM>, while the vent port <NUM> is sealed. Pressurized air may enter the cavity <NUM> through the pressure port <NUM> and then flow to the vessel through the bladder port <NUM> to inflate the vessel.

To deflate the vessel, the power supply reverses the direction of current in the coil <NUM>. By driving current through the coil <NUM> in the second, opposite direction, the actuating element <NUM> rotates to the second orientation illustrated in <FIG>. In particular, the current traveling through the coil <NUM> produces a magnetic field that acts on the actuating element <NUM> to orient the first magnetic pole 44a toward the second valve element 50b and the second magnetic pole 44b toward the first valve element 50a. The attractive magnetic force between the second end <NUM> of the magnet <NUM> in the second valve element 50b and the first magnetic pole 44a of the actuating element <NUM> draws the second valve element 50b toward the actuating element <NUM>, unsealing the vent port <NUM>. In the illustrated embodiment, the second valve element 50a is displaced to the open position in which the spacer <NUM> engages the actuating element <NUM>, and the seal <NUM> is spaced from the vent port <NUM>. Simultaneously, the magnetic repulsive force between the second end <NUM> of the magnet <NUM> in the first valve element 50a and the second magnetic pole 44b of the actuating element <NUM> pushes the first valve element 50a to its closed position so that the seal <NUM> engages and seals the pressure port <NUM>.

Thus, in the deflating configuration of the valve <NUM> illustrated in <FIG>, the vent port <NUM> is open to the chamber <NUM> and the bladder port <NUM>, while the pressure port <NUM> is sealed. Pressurized air contained within the vessel may enter the cavity <NUM> through the bladder port <NUM> and then be vented to the surrounding atmosphere through the vent port <NUM>.

Because the illustrated actuating element <NUM> rotates to actuate the valve <NUM> between the inflating configuration (<FIG>) and the deflating configuration (<FIG>), a smaller force is required to separate the magnetic poles 44a, 44b from the respective magnets <NUM>. Specifically, as the actuating element <NUM> rotates, the actuating element <NUM> and the magnets <NUM> separate in a shearing motion, which requires less force (e.g., only about <NUM>% of the force in some embodiments) than separating magnets axially (i.e. pulling magnets apart in a direction opposite the magnetic attraction force). Because the actuating element <NUM> is more easily disengaged from the valve elements 50a, 50b, the power source does not need to drive as much current through the coil <NUM> to reorient the actuating element <NUM>. Additionally, in the illustrated embodiment, the low-friction spacers <NUM> allow the actuating element <NUM> to easily rotate, even when one of the valve elements 50a, 50b is in contact with the actuating element <NUM>. The thickness of each spacer <NUM> is selected to provide a desired amount of magnetic force developed between the actuating element <NUM> and the magnets <NUM>.

The illustrated valve <NUM> has the advantage that the actuating element <NUM> drives the displacement of the valve elements 50a, 50b to both the closed and open positions. No extra components are required within the actuator assembly <NUM> to bias the valve elements 50a, 50b to either the closed or open positions. With fewer parts, the magnetically controlled valve <NUM> can be made more compact than typical valves and may require less maintenance.

<FIG> illustrate a valve <NUM> according to another embodiment. The valve <NUM> is similar in some aspects to the valve <NUM> described above with reference to <FIG>. Accordingly, features and elements of the valve <NUM> corresponding with features and elements of the valve <NUM> are given corresponding reference numbers, plus <NUM>.

The valve <NUM> includes a housing <NUM>. The housing <NUM> is generally cylindrical and has a first end wall <NUM>, a second end wall <NUM>, and a side wall <NUM> extending between the end walls <NUM>, <NUM> (<FIG>). A plurality of legs <NUM> extends from the side wall <NUM>, which may facilitate mounting the valve <NUM> in various ways. In other embodiments, the housing <NUM> may have other shapes and mounting configurations.

Referring to <FIG>, the walls <NUM>, <NUM>, <NUM> collectively define a cavity <NUM> within the housing <NUM>. An electrically conductive coil <NUM> is coupled to the side wall <NUM> (e.g., in a recess formed in the side wall <NUM>), such that the coil <NUM> is concentrically aligned with the cavity <NUM>. A power source (not shown) is electrically coupled to the coil <NUM> so that the power source and the coil <NUM> form a circuit in which the power source is able to drive current through the coil <NUM>. In the illustrated embodiment, the power source is capable of selectively driving current through the coil <NUM> in a first (e.g., positive) direction and a second (e.g., negative) direction. In some embodiments, the direction of current flow through the coil <NUM> may be selectively varied using a positive to negative converter, by selectively electrically coupling two different power sources to the coil <NUM>, or by any other suitable means. In some embodiments, the power source may include a pulse-width modulation (PWM) controller able to selectively vary a duty cycle of current driven in the first direction to current driven in the second direction at high frequency.

The illustrated valve <NUM> includes three ports: a first port or pressure port <NUM>, a second port or bladder port <NUM>, and a third port or vent port <NUM>. In the illustrated embodiment, the pressure port <NUM> extends from the first end wall <NUM>, the vent port <NUM> extends from the second end wall <NUM>, and the bladder port <NUM> extends from the side wall <NUM>. In some embodiments, the ports <NUM>, <NUM>, <NUM> may extend from different portions of the housing <NUM>, or the ports <NUM>, <NUM>, <NUM> may be recessed into the housing <NUM>. In some embodiments, the ports <NUM>, <NUM>, <NUM> may be configured differently (e.g., the first port <NUM> may be the vent port, and the third port <NUM> may be the pressure port, etc.).

With reference to <FIG>, an actuator assembly <NUM> is contained within the cavity <NUM> of the housing <NUM>. The actuator assembly <NUM> includes a first valve element 150a, a second valve element 150b, and an actuating element <NUM>. In the illustrated embodiment, the pressure port <NUM> and the vent port <NUM> each include a chamber <NUM> extending into the cavity <NUM>. The chamber <NUM> of the pressure port <NUM> includes an interior pressure port opening <NUM>, and the chamber <NUM> of the vent port <NUM> includes an interior vent port opening <NUM>.

The first valve element 150a is disposed within the chamber <NUM> of the pressure port <NUM>, and the second valve element 150b is disposed within the chamber <NUM> of the vent port <NUM>. Each of the valve elements 150a, 150b includes a permanent magnet <NUM> having a first end <NUM> and a second end <NUM> opposite the first end <NUM>. The first ends <NUM> of the magnets <NUM> face away from the actuating element <NUM>, and the second ends <NUM> of the magnets <NUM> face toward the actuating element <NUM>. The first end <NUM> has a first magnetic polarity (e.g. north), and a second end <NUM> has a second, opposite magnetic polarity (e.g. south). In the illustrated embodiment, the permanent magnets <NUM> are rare earth magnets made of NdFeB or any other suitable magnetic material. The magnets <NUM> are nickel plated, axially magnetized, and cylindrical in shape, with a diameter of about <NUM>/<NUM>-inch and a thickness of about <NUM>/<NUM>-inch. In other embodiments, the magnets <NUM> may be made with different magnetic materials and formed in different shapes or dimensions.

Each of the valve elements 150a, 150b further includes a seal <NUM> coupled to the second end <NUM> of the magnet <NUM>. Biasing elements <NUM>, which are coil springs in the illustrated embodiment, engage the first ends <NUM> of the magnets <NUM> to bias the valve elements 150a, 150b toward the actuating element <NUM>. In the illustrated embodiment, the biasing elements <NUM> are accommodated within the pressure port <NUM> and the vent port <NUM>, respectively.

With continued reference to <FIG>, the actuating element <NUM> is located within the cavity <NUM> between the chambers <NUM> and is surrounded by the coil <NUM>. In the illustrated embodiment, the actuating element <NUM> is a spherical permanent magnet (e.g., a rare earth magnet such as NeFeB) that is nickel plated and axially magnetized. The actuating element <NUM> has a diameter of <NUM>/<NUM> inch in the illustrated embodiment, but the actuating element <NUM> may be made from different magnetic materials and formed in different shapes or dimensions in other embodiments. For example, in some embodiments, the actuating element <NUM> may be shaped as a cylinder. The actuating element <NUM> includes a first magnetic pole 144a (e.g., a north pole) and a second magnetic pole 144b (e.g., a south pole) opposite the first magnetic pole 144a. In the illustrated embodiment, the first magnetic pole 144a has the same magnetic polarity as the first ends <NUM> of the magnets <NUM>, and the second magnetic pole 144b has the same magnetic polarity as the second ends <NUM> of the magnets <NUM>.

The actuating element <NUM> is rotatable between a first orientation (<FIG>) and a second orientation (<FIG>) in response to the power supply driving current through the coil <NUM> in the first direction and the second direction, respectively. In the illustrated embodiment, the actuating element <NUM> is also rotatable to a third orientation (<FIG>) between the first orientation and the second orientation in response to the power supply switching between driving current in the first direction and the second direction at a high frequency (e.g., via PWM control).

The first valve element 150a is movable between a closed position (<FIG> and <FIG>), in which the seal <NUM> of the first valve element 150a engages and seals the pressure port opening <NUM>, and an open position (<FIG>) in which the seal <NUM> of the first valve element 150a is spaced from the pressure port opening <NUM> to allow fluid to flow through the pressure port <NUM>. Likewise, the second valve element 150b is moveable between a closed position (<FIG> and <FIG>) in which the seal <NUM> of the second valve element 150b engages and seals the vent port opening <NUM> and an open position (<FIG>) in which the seal <NUM> of the second valve element 150b is spaced from the vent port opening <NUM> to allow fluid to flow through the vent port <NUM>. The valve elements 150a, 150b are movable between their respective open and closed positions under the influence of magnetic attraction and repulsion in response to rotation of the actuating element <NUM>, and under the influence of the biasing elements <NUM>.

In operation, to inflate the vessel coupled to the bladder port <NUM>, the power supply is energized to drive current through the coil <NUM> in the first direction, moving the actuating element <NUM> to the first orientation illustrated in <FIG>. In particular, the current traveling through the coil <NUM> produces a magnetic field that acts on the actuating element <NUM> to orient the second magnetic pole 144b toward the first valve element 150a and the first magnetic pole 144a toward the second valve element 150b. The magnetic repulsive force between the second end <NUM> of the magnet <NUM> of the first valve element 150a and the second magnetic pole 144b of the actuating element <NUM> pushes the first valve element 150a to its open position against the force of the biasing element <NUM>. In its open position, the seal <NUM> of the first valve element 150a is spaced from the pressure port opening <NUM>. Simultaneously, the attractive magnetic force between the second end <NUM> of the magnet <NUM> of the second valve element 150b and the first magnetic pole 144a of the actuating element <NUM> combines with the force of the biasing element <NUM> to hold the second valve element 150b in its closed position with the seal <NUM> engaged against the vent port opening <NUM>.

Thus, in the inflating configuration of the valve <NUM> illustrated in <FIG>, the pressure port <NUM> is open to the chamber <NUM> and the bladder port <NUM>, while the vent port <NUM> is sealed at the vent port opening <NUM>. Pressurized air may enter the cavity <NUM> through the pressure port <NUM> and then flow to the vessel through the bladder port <NUM> to inflate the vessel.

To deflate the vessel, the power supply reverses the direction of current in the coil <NUM>. By driving current through the coil <NUM> in the second, opposite direction, the actuating element <NUM> rotates to the second orientation illustrated in <FIG>. In particular, the current traveling through the coil <NUM> produces a magnetic field that acts on the actuating element <NUM> to orient the second magnetic pole 144b toward the second valve element 150b and the first magnetic pole 144a toward the first valve element 150a. The magnetic repulsive force between the second end <NUM> of the magnet <NUM> of the second valve element 150b and the second magnetic pole 144b of the actuating element <NUM> pushes the second valve element 150b to its open position against the force of the biasing element <NUM>. In its open position, the seal <NUM> of the second valve element 150b is spaced from the vent port opening <NUM>. Simultaneously, the attractive magnetic force between the second end <NUM> of the magnet <NUM> of the first valve element 150a and the first magnetic pole 144a combines with the force of the biasing element <NUM> to hold the first valve element 150a in its closed position with the seal <NUM> engaged against the pressure port opening <NUM>.

Thus, in the deflating configuration of the valve <NUM> illustrated in <FIG>, the vent port <NUM> is open to the chamber <NUM> and the bladder port <NUM>, while the pressure port <NUM> is sealed at the pressure port opening <NUM>. Pressurized air contained within the vessel may enter the cavity <NUM> through the bladder port <NUM> and then be vented to the surrounding atmosphere through the vent port <NUM>.

In some embodiments, the valve <NUM> may also be actuated to a closed or neutral configuration illustrated in <FIG>. As such, the valve <NUM> may be configured as a three port-three position valve (i.e. <NUM>/<NUM> valve) instead of a three port-two position valve (i.e. a <NUM>/<NUM> valve) like the valve <NUM> described above with reference to <FIG>. In such embodiments, the actuating element <NUM> is rotatable to the third orientation, illustrated in <FIG>, in response to the power supply switching between driving current in the first direction and the second direction at a high frequency (e.g., via PWM control). In the illustrated embodiment, the third orientation is midway between the first orientation and the second orientation.

When the valve <NUM> is in the neutral configuration, the first and second poles 144a, 144b of the actuating element <NUM> are oriented along a line transverse to a line passing through the magnets <NUM>. As such, the actuating element <NUM> does not exert a repulsive magnetic force on either of the valve element 150a, 150b sufficient to overcome the force of the biasing elements <NUM>. Thus, both of the valve element 150a, 150b remain closed to seal both the pressure port opening <NUM> and the vent port opening <NUM>. In the neutral configuration, the source of pressurized fluid (not shown) does not have to continuously provide pressurized air through the pressure port <NUM> to the vessel coupled to the bladder port <NUM> to keep the vessel pressurized.

In some embodiments, the valves <NUM>, <NUM> may be incorporated into an automotive seating assembly to control inflation and deflation of lumbar support bladders. In some embodiments, the valves <NUM>, <NUM> may be incorporated into a pneumatic massage system. It should be understood, however, that the valves <NUM>, <NUM> may be used in a wide range of different applications in which compact valves with relatively low energy requirements are desirable.

Claim 1:
A pneumatic valve (<NUM>) comprising:
a housing (<NUM>) including a first port (<NUM>), a second port (<NUM>), and a third port (<NUM>), wherein each of the first port (<NUM>), second port (<NUM>) and third port (<NUM>) is in fluid communication with a chamber (<NUM>) located within the housing (<NUM>);
a first valve element (50a) located within the chamber (<NUM>) and including a first magnet (<NUM>), wherein the first valve element (50a) is movable between an open position and a closed position, and the first valve element (50a) is configured to seal the first port (<NUM>) in the closed position;
a second valve element (50b) located within the chamber (<NUM>) and including a second magnet (<NUM>), wherein the second valve element (50b) is movable between an open position and a closed position, and the second valve element (50b) is configured to seal the third port (<NUM>) in the closed position; and
a magnetic actuating element (<NUM>) located within the chamber (<NUM>) between the first valve element (50a) and the second valve element (50b) and rotatable between a first position and a second position,
wherein the first valve element (50a) and the second valve element (50b) are movable between the open position and the closed position in response to rotation of the magnetic actuating element (<NUM>) between the first position and the second position,
wherein the magnetic actuating element (<NUM>) is configured to attract the first valve element (50a) toward the open position and to repel the second valve element (50b) toward the closed position in the first position of the magnetic actuating element (<NUM>), and
the magnetic actuating element (<NUM>) is configured to repel the first valve element (50a) toward the closed position and to attract the second valve element (50b) toward the open position in the second position of the magnetic actuating element (<NUM>) such that when the first valve element (50a) is in the open position, the second valve element (50b) is maintained in the closed position, and, when the second valve element (50b) is in the open position, the first valve element (50a) is maintained in the closed position.