Patent Grant
9279433
This disclosure relates to an assembly of poppet valves in general, and an assembly of multiple poppet valves that act to control a pneumatic actuator in particular.
Electro-pneumatic positioners are mechanical devices that control the position of a pneumatic actuator based on digital input signals provided by a programmable controller, such as a programmable logic controller. Generally, the controller is connected to an I/P (current to pressure) converter, which is in turn connected to one or more control valves. The I/P converter controls the control valves that are each in fluid communication with both a supply of pressurized fluid, such as pressurized air, and one or more volumes within the pneumatic actuator. Based on a command from the controller to the I/P converter, the I/P converter opens the control valve to allow the pressurized fluid from the supply into one of the volumes of the pneumatic actuator. This pressurized air acts on the surface of a piston defining part of the volume within the pneumatic actuator, thereby moving the piston and an actuator arm coupled to the piston into a desired position.
Spool valves and poppet valves are commonly used as control valves in electro-pneumatic applications. Generally, spool designs have a compact form factor due to the linear displacement of a cylindrical spool element within a housing. Poppet valve assemblies can be used in a wide range of operational environments, but can have a larger form factor than spool designs. Poppet valve assemblies generally include a combination of two normally open poppet valves and two normally closed poppet valves. A pair of valve plugs are coupled to a single axially-displaceable shaft to form the first set of normally closed and normally open poppet valves. A second shaft having a second pair of valve plugs forms the second set of normally closed and normally open poppet valves. When each shaft is in a first valve position, the valve plug for the normally closed poppet valve is sealingly engaged with a corresponding valve seat, and the valve plug for the normally open poppet valve is disengaged from a corresponding valve seat. When the shaft is axially displaced to a second shaft position, the valve plug for the normally closed poppet valve is moved to a position such that it is disengaged from the corresponding valve seat, and the valve plug for the normally open poppet valve is moved to a position such that it sealingly engages the corresponding valve seat. When the shaft is axially displaced to return to the first shaft position, the valve plug for the normally closed poppet valve is moved to a position such that it sealingly engages the corresponding valve seat, and the valve plug for the normally open poppet valve is moved to a position such that it is disengaged from the corresponding valve seat. The cycle repeats as the valve shaft is axially reciprocated from the first position to the second position, and back to the first position.
In accordance with one exemplary aspect of the present invention, a poppet valve assembly may include a valve housing having a central bore. A first module may be disposed within the central bore, and the first module may include a first normally closed poppet valve and a second normally closed poppet valve. Each of the first and second normally closed poppet valves may have an open position and a closed position. A central port may be formed in the first module, and the central port of the first module may be adapted to be coupled to a first volume of a pneumatic cylinder. An exhaust port may be formed in the first module such that the central port is in fluid communication with the exhaust port when the first poppet valve is in the open position. A supply port may be formed in the first module such that the central port is in fluid communication with the supply port when second poppet valve is in the open position. The supply port may be configured to be in fluid communication with a supply of pressurized fluid such that when the second poppet valve is in the open position, pressurized fluid is provided to the first volume of the pneumatic cylinder. The exhaust port may be configured to vent pressurized fluid from the first volume of the pneumatic cylinder when the first poppet valve is in the open position.
In accordance with another exemplary aspect of the present invention, the first normally closed poppet valve includes a first volume and the second normally closed poppet valve includes a second volume.
In accordance with yet another exemplary aspect of the present invention, a first poppet port may be formed in the first module. The first poppet port may be in fluid communication with the first volume and adapted to be both an inlet and an outlet for a pressurized fluid. A second poppet port may formed in the first module. The second poppet port may be in fluid communication with the second volume and adapted to be both an inlet and an outlet for a pressurized fluid.
In accordance with still one more exemplary aspect of the present invention, the first poppet valve may include a first diaphragm circumferentially secured to the first module, and the first diaphragm may at least partially define the first volume. A first valve plug may be coupled to the first diaphragm, and a first valve seat may be formed in a first central aperture that is in fluid communication with the central passage. A first spring may be disposed within the first volume that biases the first valve plug into sealing engagement with the first valve seat such that the first poppet valve is normally closed. The second poppet valve may include a second diaphragm circumferentially secured to the first module, and the second diaphragm may at least partially define the second volume. A second valve plug may be coupled to the second diaphragm, and a second valve seat may be formed in a second central aperture that is in fluid communication with the central passage. A second spring may be disposed within the second volume that biases the second valve plug into sealing engagement with the second valve seat such that the second poppet valve is normally closed.
In accordance with a further exemplary aspect of the present invention, the poppet valve assembly may also include a second module disposed adjacent to the first module within the central bore, and the second module may include a third normally closed poppet valve and a fourth normally closed poppet valve. A central port may be formed in the second module, and the central port of the second module may be adapted to be coupled to a second volume within the pneumatic cylinder. An exhaust port may be formed in the second module such that the central port of the second module is in fluid communication with the exhaust port of the second module when the third poppet valve is in the open position. A supply port may be formed in the second module such that the central port of the second module is in fluid communication with the supply port of the second module when the fourth poppet valve is in the open position. The supply port of the second module may be configured to be in fluid communication with a supply of pressurized fluid such that when the fourth poppet valve is open, pressurized fluid is provided to the second volume within the pneumatic cylinder. The exhaust port of the second module may be configured to vent pressurized fluid from the second volume within the pneumatic cylinder when the third poppet valve is open.
In accordance with another exemplary aspect of the present invention, a third poppet port may be formed in the second module, the third poppet port being in fluid communication with the third volume and adapted to be both an inlet and an outlet for a pressurized fluid. A fourth poppet port may be formed in the second module, the fourth poppet port being in fluid communication with the fourth volume and adapted to be both an inlet and an outlet for a pressurized fluid.
In accordance with yet one more exemplary aspect of the present invention, the third normally closed poppet valve may include a third volume and the fourth normally closed poppet valve may include a fourth volume.
In accordance with a further exemplary aspect of the present invention, the first poppet valve may include a third diaphragm circumferentially secured to the second module, and the third diaphragm may at least partially define the third volume. A third valve plug may be coupled to the third diaphragm and a third valve seat may be formed in a second central aperture that is in fluid communication with the central passage of the second module. A third spring may be disposed within the third volume that may bias the third valve plug into sealing engagement with the third valve seat such that the third poppet valve is normally closed. The fourth poppet valve may include a fourth diaphragm circumferentially secured to the second module, the fourth diaphragm at least partially defining the fourth volume. A fourth valve plug may be coupled to the fourth diaphragm, and a fourth valve seat may be formed in a second central aperture that is in fluid communication with the central passage of the second module. A fourth spring may be disposed within the fourth volume that may bias the fourth valve plug into sealing engagement with the fourth valve seat such that the fourth poppet valve is normally closed.
In accordance with yet one more exemplary aspect of the present invention, the first poppet valve may be configured to be maintained in the closed position by a supply of pressurized fluid introduced into the first volume, and the second poppet valve may be configured to be maintained in the closed position by a supply of pressurized fluid introduced into the second volume.
In accordance with another exemplary aspect of the present invention, the central bore of the housing may be cylindrical. Additionally, the first module may be cylindrical and sized to be received into the cylindrical central bore. Furthermore, the first module and second module may both be cylindrical and sized to be received into the central bore.
In accordance with another exemplary aspect of the present invention, a system for controlling a pneumatic actuator may include a supply of pressurized fluid. A first module may be disposed within a valve housing, and the first module may include a first normally closed poppet valve and a second normally closed poppet valve, wherein each of the first and second poppet valves has an open position and a closed position. A central port may be formed in the first module that is in fluid communication with a first volume of the pneumatic actuator. An exhaust port may be formed in the first module, the exhaust port being in fluid communication with the atmosphere such that the central port, and the first volume of the pneumatic actuator in fluid communication with the central port, is in fluid communication with the atmosphere when the first poppet valve is in the open position, and the central port, and the first volume of the pneumatic actuator in fluid communication with the central port, is not in fluid communication with the atmosphere when the first poppet valve is in the closed position. A supply port may be formed in the first module, the supply port being in fluid communication with the supply of pressurized fluid such that the central port, and the first volume of the pneumatic actuator in fluid communication with the central port, is in fluid communication with the supply of pressurized fluid when second poppet valve is in the open position, and the central port, and the first volume of the pneumatic actuator in fluid communication with the central port, is not in fluid communication with the supply of pressurized fluid when second poppet valve is in the closed position. A first control valve may have a supply port, a work port, and an exhaust port, wherein the supply port of the first control valve is in fluid communication with the supply of pressurized fluid, the work port of the first control valve is in fluid communication with the second poppet valve, and the exhaust port of the first control valve is in fluid communication with the atmosphere. A second control valve may have a supply port, a work port, and an exhaust port, wherein the supply port of the second control valve is in fluid communication with the supply of pressurized fluid, the work port of the second control valve is in fluid communication with the first poppet valve, and the exhaust port of the second control valve is in fluid communication with the atmosphere. The first volume of the pneumatic actuator may be partially defined by a first side of a piston and an interior surface of an actuator body, and an actuator arm may be secured to the piston such that when the supply of pressurized fluid is in fluid communication with the first volume of the pneumatic actuator, a force on the piston caused by the pressurized fluid displaces the actuator arm.
In accordance with a still further exemplary aspect of the present invention, the first control valve may have a first position and a second position, wherein in the first position, the work port of the first control valve may be in fluid communication with the exhaust port of the first control valve. In the second position, the work port of the first control valve may be in fluid communication with the supply port of the first control valve. The second control valve may have a first position and a second position, and in the first position, the work port of the second control valve is in fluid communication with the supply port of the second control valve, and in the second position the work port of the second control valve is in fluid communication with the exhaust port of the second control valve.
In accordance with one more exemplary aspect of the present invention, when the second control valve is in the first position, the first poppet valve may be moved to the closed position by pressurized fluid from the supply. And when the first control valve is in the first position, the second poppet valve may be opened by pressurized fluid from the first volume of the pneumatic actuator acting on a portion of the second poppet valve.
In accordance with yet one more exemplary aspect of the present invention, when the first control valve is in the second position, the second poppet valve may be moved to the closed position by pressurized fluid from the supply, and when the second control valve is in the second position, the first poppet valve may be opened by pressurized fluid from the first volume of the pneumatic actuator acting on a portion of the first poppet valve.
In accordance with a still further exemplary aspect of the present invention, when the first control valve and the second control valve are both in the first position, pressurized fluid may enter the first volume of the pneumatic actuator such that the longitudinal arm is displaced in a first direction. And when the first control valve and the second control valve are both in the second position, pressurized fluid may exit the first volume of the pneumatic actuator such that the longitudinal arm is displaced in a second direction opposite the first direction.
In accordance with a further exemplary aspect of the present invention, the first control valve may be a 3/2 pilot valve and the second control valve may be a 3/2 shuttle valve. Alternatively, the first control valve may be a 3/2 shuttle valve and the second control valve may be a 3/2 pilot valve. Further, the first control valve may be a 3/2 pilot valve and the second control valve may be a 3/2 pilot valve.
In accordance with another exemplary aspect of the present invention, the first normally closed poppet valve may include a first volume, and a first poppet port may be formed in the first module such that the first poppet port is in fluid communication with the first volume. The second normally closed poppet valve may include a second volume, and a second poppet port may be formed in the first module such that the second poppet port is in fluid communication with the second volume.
In accordance with still another exemplary aspect of the present invention, the first poppet valve may include a first diaphragm circumferentially secured to the first module, and the first diaphragm may at least partially define the first volume. A first valve plug may be coupled to the first diaphragm, and a first valve seat may be formed in a first central aperture that is in fluid communication with the central passage. A first spring may be disposed within the first volume that biases the first valve plug into sealing engagement with the first valve seat such that the first poppet valve is normally closed. The second poppet valve may include a second diaphragm circumferentially secured to the first module, and the second diaphragm may at least partially define the second volume. A second valve plug may be coupled to the second diaphragm, and a second valve seat may be formed in a second central aperture that is in fluid communication with the central passage. A second spring may be disposed within the second volume that biases the second valve plug into sealing engagement with the second valve seat such that the second poppet valve is normally closed.
In accordance with one more exemplary aspect of the present invention, the first poppet valve may be closed when pressurized fluid from the supply enters the first volume of the first poppet valve and acts on the first diaphragm such that the first valve plug coupled to the first diaphragm is displaced towards the first valve seat. The first poppet valve may be opened when pressurized fluid within the first volume of the first poppet valve exits the first volume of the first poppet valve, and pressurized fluid from the first volume of the pneumatic actuator acts on the first valve plug and the first diaphragm, resulting in a force that overcomes the biasing force of the first spring, thereby displacing the first valve plug away from the first valve seat.
In accordance with yet another exemplary aspect of the present invention, the second poppet valve may be closed when pressurized fluid from the supply enters the second volume of the second poppet valve and acts on the second diaphragm such that the second valve plug coupled to the second diaphragm is displaced towards the second valve seat. The second poppet valve may be opened when pressurized fluid within the second volume of the second poppet valve exits the second volume of the second poppet valve, and pressurized fluid from the first volume of the pneumatic actuator acts on the first valve plug and the first diaphragm, resulting in a force that overcomes the biasing force of the first spring, thereby displacing the first valve plug away from the first valve seat.
In accordance with another exemplary aspect of the present invention, a second module may be disposed within the valve housing adjacent to the first module. The second module may include a third normally closed poppet valve and a fourth normally closed poppet valve, wherein each of the third and fourth poppet valves has an open position and a closed position. A second central port may be formed in the second module that is in fluid communication with a second volume of the pneumatic actuator. A second exhaust port may be formed in the second module, the second exhaust port being in fluid communication with the atmosphere such that the second central port, and the second volume of the pneumatic actuator in fluid communication with the second central port, is in fluid communication with the atmosphere when the third poppet valve is in the open position, and the second central port, and the second volume of the pneumatic actuator in fluid communication with the second central port, is not in fluid communication with the atmosphere when the third poppet valve is in the closed position. A supply port may be formed in the second module, the supply port being in fluid communication with the supply of pressurized fluid such that the second central port, and the second volume of the pneumatic actuator in fluid communication with the second central port, is in fluid communication with the supply of pressurized fluid when the fourth poppet valve is in the open position, and the second central port, and the second volume of the pneumatic actuator in fluid communication with the second central port, is not in fluid communication with the supply of pressurized fluid when the fourth poppet valve is in the closed position. The work port of the first control valve may be in fluid communication with the third poppet valve, and the work port of the second control valve may be in fluid communication with the fourth poppet valve, and the second volume of the pneumatic actuator may be partially defined by a second side of the piston and the interior surface of an actuator such that when the supply of pressurized fluid is in fluid communication with the second volume of the pneumatic actuator, a force on the piston caused by the pressurized fluid displaces the actuator arm.
In accordance with even one more exemplary aspect of the present invention, when the second control valve is in the first position, the first poppet valve and the fourth poppet valves may be moved to the closed position by pressurized fluid from the supply, and when the first control valve is in the first position, the second poppet valve may be opened by pressurized fluid from the first volume of the pneumatic actuator acting on a portion of the second poppet valve. The third poppet valve may be opened by pressurized fluid from the second volume of the pneumatic actuator acting on a portion of the third poppet valve.
In accordance with still another exemplary aspect of the present invention, when the first control valve is in the second position, the second poppet valve and third poppet valves may be moved to the closed position by pressurized fluid from the supply, and when the second control valve is in the second position, the first poppet valve may be opened by pressurized fluid from the first volume of the pneumatic actuator acting on a portion of the first poppet valve. The fourth poppet valve may be opened by pressurized fluid from the second volume of the pneumatic actuator acting on a portion of the fourth poppet valve.
In accordance with yet one more exemplary aspect of the present invention, when the first control valve and the second control valve are both in the first position, pressurized fluid may enter the first volume of the pneumatic actuator and may exit the second volume of the pneumatic actuator such that the longitudinal arm is displaced in a first direction. And when the first control valve and the second control valve are both in the second position, pressurized fluid may exit the first volume of the pneumatic actuator and enter the second volume of the pneumatic actuator such that the longitudinal arm is displaced in a second direction opposite the first direction.
In accordance with a further exemplary aspect of the present invention, the first control valve may be a 3/2 pilot valve and the second control valve may be a 3/2 shuttle valve. Alternatively, the first control valve may be a 3/2 shuttle valve and the second control valve may be a 3/2 pilot valve. Further, the first control valve may be a 3/2 pilot valve and the second control valve may be a 3/2 pilot valve.
In accordance with a further exemplary aspect of the present invention, the first poppet valve may include a first volume, and a first poppet port may be formed in the first module such that the first poppet port is in fluid communication with the first volume. The second poppet valve may include a second volume, and a second poppet port may be formed in the first module such that the second poppet port is in fluid communication with the second volume. The third poppet valve may include a third volume, and a third poppet port may be formed in the first module such that the third poppet port is in fluid communication with the third volume. The fourth poppet valve may include a fourth volume, and a fourth poppet port may be formed in the first module such that the fourth poppet port is in fluid communication with the fourth volume.
In accordance with another exemplary aspect of the present invention, the first poppet valve may include a first diaphragm circumferentially secured to the first module, and the first diaphragm may at least partially define the first volume. A first valve plug may be coupled to the first diaphragm, and a first valve seat may be formed in a first central aperture that is in fluid communication with the central passage. A first spring may be disposed within the first volume biasing the first valve plug into sealing engagement with the first valve seat such that the first poppet valve is normally closed. The second poppet valve may include a second diaphragm circumferentially secured to the first module, and the second diaphragm may at least partially define the second volume. A second valve plug may be coupled to the second diaphragm. A second valve seat may be formed in a second central aperture that is in fluid communication with the central passage. A second spring may be disposed within the second volume biasing the second valve plug into sealing engagement with the second valve seat such that the second poppet valve is normally closed. The third poppet valve may include a third diaphragm circumferentially secured to the first module, and the third diaphragm may at least partially define the third volume. A third valve plug may be coupled to the third diaphragm, and a third valve seat may be formed in a third central aperture that is in fluid communication with the second central passage. A third spring may be disposed within the third volume biasing the third valve plug into sealing engagement with the third valve seat such that the third poppet valve is normally closed. The fourth poppet valve may include a fourth diaphragm circumferentially secured to the first module, and the fourth diaphragm may at least partially define the fourth volume. A fourth valve plug may be coupled to the fourth diaphragm, and a fourth valve seat may be formed in a fourth central aperture that is in fluid communication with the second central passage. A fourth spring may be disposed within the fourth volume biasing the fourth valve plug into sealing engagement with the fourth valve seat such that the fourth poppet valve is normally closed.
In accordance with yet another exemplary aspect of the present invention, the first poppet valve may be closed when pressurized fluid from the supply enters the first volume of the first poppet valve and acts on the first diaphragm such that the first valve plug coupled to the first diaphragm is displaced towards the first valve seat. The first poppet valve may be opened when pressurized fluid within the first volume of the first poppet valve exits the first volume of the first poppet valve, and pressurized fluid from the first volume of the pneumatic actuator acts on the first valve plug and the first diaphragm, resulting in a force that overcomes the biasing force of the first spring, thereby displacing the first valve plug away from the first valve seat.
In accordance with still one more exemplary aspect of the present invention, the second poppet valve may be closed when pressurized fluid from the supply enters the second volume of the second poppet valve and acts on the second diaphragm such that the second valve plug coupled to the second diaphragm is displaced towards the second valve seat. The second poppet valve may be opened when pressurized fluid within the second volume of the second poppet valve exits the second volume of the second poppet valve, and pressurized fluid from the first volume of the pneumatic actuator acts on the second valve plug and the second diaphragm, resulting in a force that overcomes the biasing force of the second spring, thereby displacing the second valve plug away from the second valve seat.
In accordance with one more exemplary aspect of the present invention, the third poppet valve may be closed when pressurized fluid from the supply enters the third volume of the third poppet valve and acts on the third diaphragm such that the third valve plug coupled to the third diaphragm is displaced towards the third valve seat. The third poppet valve may be opened when pressurized fluid within the third volume of the third poppet valve exits the third volume of the first poppet valve, and pressurized fluid from the second volume of the pneumatic actuator acts on the third valve plug and the third diaphragm, resulting in a force that overcomes the biasing force of the third spring, thereby displacing the third valve plug away from the third valve seat.
In accordance with a further exemplary aspect of the present invention, the fourth poppet valve may be closed when pressurized fluid from the supply enters the fourth volume of the fourth poppet valve and acts on the fourth diaphragm such that the fourth valve plug coupled to the fourth diaphragm is displaced towards the fourth valve seat. The fourth poppet valve may be opened when pressurized fluid within the fourth volume of the fourth poppet valve exits the fourth volume of the fourth poppet valve, and pressurized fluid from the second volume of the pneumatic actuator acts on the fourth valve plug and the fourth diaphragm, resulting in a force that overcomes the biasing force of the fourth spring, thereby displacing the fourth valve plug away from the fourth valve seat.
In accordance with yet one more exemplary aspect of the present invention, when the work port of the first control valve is in fluid communication with the supply port of the first control valve, and the work port of the second control valve is in fluid communication with the supply port of the second control valve, pressurized fluid cannot be vented from the first volume and second volume of the pneumatic actuator, thereby preventing the actuator arm from being displaced in either the first direction or the second direction.
In accordance with yet another more exemplary aspect of the present invention, the pressurized fluid may be compressed air.
In accordance with one more exemplary aspect of the present invention, a system for controlling a pneumatic actuator may include a supply of pressurized fluid. A first module may be disposed within a valve housing, the first module including a first normally closed poppet valve and a second normally closed poppet valve, wherein each of the first and second poppet valves has an open position and a closed position. A first central port may be formed in the first module that is in fluid communication with a first volume of the pneumatic actuator. A first exhaust port may be formed in the first module, the first exhaust port being in fluid communication with the atmosphere such that the first central port, and the first volume of the pneumatic actuator in fluid communication with the first central port, is in fluid communication with the atmosphere when the first poppet valve is in the open position, and the first central port, and the first volume of the pneumatic actuator in fluid communication with the first central port, is not in fluid communication with the atmosphere when the first poppet valve is in the closed position. A first supply port may be formed in the first module, the first supply port being in fluid communication with the supply of pressurized fluid such that the first central port, and the first volume of the pneumatic actuator in fluid communication with the first central port, is in fluid communication with the supply of pressurized fluid when second poppet valve is in the open position, and the first central port, and the first volume of the pneumatic actuator in fluid communication with the first central port, is not in fluid communication with the supply of pressurized fluid when second poppet valve is in the closed position. A second module may be disposed within the valve housing adjacent to the first module, and the second module may include a third normally closed poppet valve and a fourth normally closed poppet valve, wherein each of the third and fourth poppet valves has an open position and a closed position. A second central port may be formed in the second module that is in fluid communication with a second volume of the pneumatic actuator. A second exhaust port may be formed in the second module, the second exhaust port being in fluid communication with the atmosphere such that the second central port, and the second volume of the pneumatic actuator in fluid communication with the second central port, is in fluid communication with the atmosphere when the third poppet valve is in the open position, and the second central port, and the second volume of the pneumatic actuator in fluid communication with the second central port, is not in fluid communication with the atmosphere when the third poppet valve is in the closed position. A supply port may be formed in the second module, the supply port being in fluid communication with the supply of pressurized fluid such that the second central port, and the second volume of the pneumatic actuator in fluid communication with the second central port, is in fluid communication with the supply of pressurized fluid when fourth poppet valve is in the open position, and the second central port, and the second volume of the pneumatic actuator in fluid communication with the second central port, is not in fluid communication with the supply of pressurized fluid when fourth poppet valve is in the closed position. A first control valve may have a supply port, a first work port, a second work port, a first exhaust port, and a second exhaust port, wherein the supply port of the first control valve is in fluid communication with the supply of pressurized fluid, the first work port of the first control valve is in fluid communication with the second poppet valve and third poppet valve, the second work port of the first control valve is in fluid communication with the first poppet valve and fourth poppet valve, and the first exhaust port and second exhaust port of the first control valve is in fluid communication with the atmosphere. The first volume of the pneumatic actuator may be partially defined by a first surface of a piston and an interior surface of an actuator body, and an actuator arm is secured to the piston such that when the supply of pressurized fluid is in fluid communication with the first volume of the pneumatic actuator, a force on the first surface of the piston caused by the pressurized fluid may displace the actuator arm in a first direction. The second volume of the pneumatic actuator may be partially defined by a second side of the piston and the interior surface of an actuator such that when the supply of pressurized fluid is in fluid communication with the second volume of the pneumatic actuator, a force on the second surface of the piston caused by the pressurized fluid displaces the actuator arm in a second direction opposite the first direction.
In accordance with yet one more exemplary aspect of the present invention, the first control valve may have a first position and a second position. In the first position, the first work port of the first control valve may be in fluid communication with the first exhaust port of the first control valve, and the second work port of the first control valve may be in fluid communication with the supply port of the first control valve. In the second position, the first work port of the first control valve may be in fluid communication with the supply port of the first control valve, and the second work port of the first control valve may be in fluid communication with the second exhaust port of the first control valve.
In accordance with yet another exemplary aspect of the present invention, the system may include a second control valve and a third control valve. The second control valve may move the first control valve from the first position to the second position, and the third control valve may move the first control valve from the second position to the first position.
In accordance with still one more exemplary aspect of the present invention, the first control valve may be a 5/2 shuttle valve, the second control valve may be a 3/2 pilot valve, and the third control valve may be a 3/2 pilot valve. Alternatively, the first control valve may be a 5/2 spool valve, the second control valve may be a 3/2 pilot valve, and the third control valve may be a 3/2 pilot valve.
In accordance with a further exemplary aspect of the present invention, when the first control valve is in the first position, the first poppet valve and the fourth poppet valve may be moved to the closed position by pressurized fluid from the supply, the second poppet valve may be opened by pressurized fluid from the first volume of the pneumatic actuator acting on a portion of the second poppet valve, and the third poppet valve may be opened by pressurized fluid from the second volume of the pneumatic actuator acting on a portion of the third poppet valve.
In accordance with another exemplary aspect of the present invention, when the first control valve is in the second position, the second poppet valve and the third poppet valve may be moved to the closed position by pressurized fluid from the supply, the first poppet valve may be opened by pressurized fluid from the first volume of the pneumatic actuator acting on a portion of the first poppet valve, and the fourth poppet valve may be opened by pressurized fluid from the fourth volume of the pneumatic actuator acting on a portion of the fourth poppet valve.
In accordance with a further exemplary aspect of the present invention, the first poppet valve may include a first volume, and a first poppet port may be formed in the first module such that the first poppet port is in fluid communication with the first volume. The second poppet valve may include a second volume, and a second poppet port may be formed in the first module such that the second poppet port is in fluid communication with the second volume. The third poppet valve may comprise a third volume, and a third poppet port may be formed in the first module such that the third poppet port is in fluid communication with the third volume. The fourth poppet valve may include a fourth volume, and a fourth poppet port may be formed in the first module such that the fourth poppet port is in fluid communication with the fourth volume.
In accordance with one more exemplary aspect of the present invention, the first poppet valve may include a first diaphragm circumferentially secured to the first module, and the first diaphragm may at least partially define the first volume. A first valve plug may be coupled to the first diaphragm, and a first valve seat may be formed in a first central aperture that is in fluid communication with the central passage. A first spring may be disposed within the first volume that biases the first valve plug into sealing engagement with the first valve seat such that the first poppet valve is normally closed. The second poppet valve may include a second diaphragm circumferentially secured to the first module, and the second diaphragm may at least partially define the second volume. A second valve plug may be coupled to the second diaphragm. A second valve seat may be formed in a second central aperture that is in fluid communication with the central passage. A second spring may be disposed within the second volume that biases the second valve plug into sealing engagement with the second valve seat such that the second poppet valve is normally closed. The third poppet valve may include a third diaphragm circumferentially secured to the first module, and the third diaphragm may at least partially define the third volume. A third valve plug may be coupled to the third diaphragm, and a third valve seat may be formed in a third central aperture that is in fluid communication with the second central passage. A third spring may be disposed within the third volume that biases the third valve plug into sealing engagement with the third valve seat such that the third poppet valve is normally closed. The fourth poppet valve may include a fourth diaphragm circumferentially secured to the first module, and the fourth diaphragm may at least partially define the fourth volume. A fourth valve plug may be coupled to the fourth diaphragm, and a fourth valve seat may be formed in a fourth central aperture that is in fluid communication with the second central passage. A fourth spring may be disposed within the fourth volume that biases the fourth valve plug into sealing engagement with the fourth valve seat such that the fourth poppet valve is normally closed.
In accordance with a further exemplary aspect of the present invention, the first poppet valve may be closed when pressurized fluid from the supply enters the first volume of the first poppet valve and acts on the first diaphragm such that the first valve plug coupled to the first diaphragm is displaced towards the first valve seat. The first poppet valve may be opened when pressurized fluid within the first volume of the first poppet valve exits the first volume of the first poppet valve, and pressurized fluid from the first volume of the pneumatic actuator acts on the first valve plug and the first diaphragm, resulting in a force that overcomes the biasing force of the first spring, thereby displacing the first valve plug away from the first valve seat.
In accordance with one more exemplary aspect of the present invention, the second poppet valve may be closed when pressurized fluid from the supply enters the second volume of the second poppet valve and acts on the second diaphragm such that the second valve plug coupled to the second diaphragm is displaced towards the second valve seat. The second poppet valve may be opened when pressurized fluid within the second volume of the second poppet valve exits the second volume of the second poppet valve, and pressurized fluid from the first volume of the pneumatic actuator acts on the second valve plug and the second diaphragm, resulting in a force that overcomes the biasing force of the second spring, thereby displacing the second valve plug away from the second valve seat.
In accordance with a still further exemplary aspect of the present invention, the third poppet valve may be closed when pressurized fluid from the supply enters the third volume of the third poppet valve and acts on the third diaphragm such that the third valve plug coupled to the third diaphragm is displaced towards the third valve seat. The third poppet valve may be opened when pressurized fluid within the third volume of the third poppet valve exits the third volume of the first poppet valve, and pressurized fluid from the second volume of the pneumatic actuator acts on the third valve plug and the third diaphragm, resulting in a force that overcomes the biasing force of the third spring, thereby displacing the third valve plug away from the third valve seat.
In accordance with yet one more exemplary aspect of the present invention, the fourth poppet valve may be closed when pressurized fluid from the supply enters the fourth volume of the fourth poppet valve and acts on the fourth diaphragm such that the fourth valve plug coupled to the fourth diaphragm is displaced towards the fourth valve seat. The fourth poppet valve may be opened when pressurized fluid within the fourth volume of the fourth poppet valve exits the fourth volume of the fourth poppet valve, and pressurized fluid from the second volume of the pneumatic actuator acts on the fourth valve plug and the fourth diaphragm, resulting in a force that overcomes the biasing force of the fourth spring, thereby displacing the fourth valve plug away from the fourth valve seat.
In accordance with still one more exemplary aspect of the present invention, a method of operating a pneumatic cylinder may include providing a supply of pressurized fluid and operatively coupling the supply to a first control valve and a second control valve, wherein the flow of the pressurized fluid may be controlled by the first control valve and the second control valve. A first module may be provided including a first normally closed poppet valve and a second normally closed poppet valve. The method may also include operatively coupling the second control valve to the first poppet valve of the first module, wherein the first poppet valve is opened and closed by pressurized fluid flowing through the second control valve. Additionally, the method may include operatively coupling the first control valve to the second poppet valve of the first module, wherein the second poppet valve is opened and closed by pressurized fluid flowing through the first control valve. The method may also include operatively coupling the supply to the second poppet valve of the first module such that when the second poppet valve is in an open position and the first poppet valve is in a closed position, pressurized fluid is provided to a first volume within a pneumatic cylinder, resulting in a translation of the pneumatic actuator in a first direction. The method may finally include operatively coupling the first poppet valve of the first module to an exhaust port such that when the first poppet valve is in the open position and the second poppet valve is in the closed position, pressurized fluid within the first volume of the pneumatic cylinder is exhausted allowing for a translation of the pneumatic actuator in a second direction opposite to the first direction.
In accordance with a further exemplary aspect of the present invention, each of the first and second control valves may have a first position and a second position. In the first position, pressurized fluid may flow from the supply, through the control valve, and into the first or second poppet valve, thereby closing the first or second poppet valve. Each may have a second position wherein pressurized fluid may flow from the first or second poppet valve, through the control valve, and may be vented to the atmosphere, thereby allowing the first or second poppet valve to be opened.
In accordance with one more exemplary aspect of the present invention, when the first control valve is in the second position, the second control valve is in the first position, and when the first control valve is in the first position, the second control valve is in the second position. In one more exemplary aspect of the present invention, the first control valve is a pilot valve and the second control valve is a shuttle valve. In accordance with a further exemplary aspect of the present invention, the pilot valve may move the shuttle valve from the first position to the second position. Alternatively, the pilot valve may move the shuttle valve from the second position to the first position. Also, the first control valve may be a shuttle valve and the second control valve may be a pilot valve. Also, the pilot valve may move the shuttle valve from the first position to the second position, or the pilot valve may move the shuttle valve from the second position to the first position.
In accordance with a further exemplary aspect of the present invention, the first poppet valve may include a first diaphragm circumferentially secured to the first module, and the first diaphragm may at least partially define a first volume. A first valve plug may be coupled to the first diaphragm, and a first valve seat may be formed in a first central aperture of the first module that is in fluid communication with the first volume within the pneumatic cylinder. A first spring may be disposed within the first volume that biases the first valve plug into sealing engagement with the first valve seat such that the first poppet valve is normally closed. The second poppet valve may include a second diaphragm circumferentially secured to the first module, and the second diaphragm may at least partially define a second volume. A second valve plug may be coupled to the second diaphragm. A second valve seat may be formed in a second central aperture of the first module that is in fluid communication with the first volume within the pneumatic cylinder. A second spring may be disposed within the second volume that biases the second valve plug into sealing engagement with the second valve seat such that the second poppet valve is normally closed.
In accordance with a still further exemplary aspect of the present invention, the first poppet valve may be maintained in the closed position by pressurized fluid within the first volume, and the second poppet valve may be maintained in the closed position by pressurized fluid within the second volume.
In accordance with yet one more exemplary aspect of the present invention, the method may include providing a second module including a third normally closed poppet valve and a fourth normally closed poppet valve and operatively coupling the first control valve to the third poppet valve of the second module, wherein the third poppet valve is opened and closed by pressurized fluid flowing through the first control valve. The method may also include operatively coupling the second control valve to the fourth poppet valve of the second module, wherein the fourth poppet valve is opened and closed by pressurized fluid flowing through the second control valve. Additionally, the method may also include operatively coupling the supply to the fourth poppet valve of the second module such that when the fourth poppet valve is in an open position and the third poppet valve is in a closed position, pressurized fluid is provided to a second volume within the pneumatic cylinder, resulting in a translation of the pneumatic actuator in the second direction. Finally, the method may also include operatively coupling the third poppet valve of the second module to an exhaust port such that when the third poppet valve is in the open position and the fourth poppet valve is in the closed position, pressurized fluid within the second volume of the pneumatic cylinder is exhausted allowing for a translation of the pneumatic actuator in the first direction.
In accordance with another exemplary aspect of the present invention, the first control valve may have a first position and a second position. In the first position, pressurized fluid may flow from the supply, through the first control valve, and into the second and third poppet valves, thereby closing the second and third poppet valves. In the second position, pressurized fluid may flow from the second and third poppet valves, through the first control valve, and may be vented to the atmosphere, thereby allowing the second and third poppet valves to be opened.
In accordance with a further exemplary aspect of the present invention, the second control valve may have a first position and a second position, wherein in the first position, pressurized fluid flows from the supply, through the second control valve, and into the first and fourth poppet valves, thereby closing the first and fourth poppet valves. In the second position, pressurized fluid may flow from the first and fourth poppet valves, through the second control valve, and may be vented to the atmosphere, thereby allowing the first and fourth poppet valves to be opened.
In accordance with yet another exemplary aspect of the present invention, the first control valve may be a pilot valve and the second control valve may be a shuttle valve, and the pilot valve may move the shuttle valve from the first position to the second position. In accordance with a further exemplary aspect of the present invention, the first control valve may be a pilot valve and the second control valve may be a shuttle valve, and the pilot valve may move the shuttle valve from the second position to the first position. Alternatively, the first control valve may be a shuttle valve and the second control valve may be a pilot valve, and the pilot valve may move the shuttle valve from the first position to the second position. Additionally, the first control valve may be a shuttle valve and the second control valve may be a pilot valve, and the pilot valve may move the shuttle valve from the second position to the first position. Also, the first control valve may be a first pilot valve and the second control valve may be a second pilot valve.
In accordance with a further exemplary aspect of the present invention, when the first pilot valve and the second pilot valve are in the first position, the first poppet valve, the second poppet valve, the third poppet valve, and the fourth poppet valve may be maintained in the closed position such that volume of the pressurized fluid in the first and second volume within the pneumatic cylinder remains constant, thereby preventing the pneumatic cylinder from translating in either the first direction or the second direction.
In accordance with a still further exemplary aspect of the present invention, the third poppet valve may include a third diaphragm circumferentially secured to the first module, and the third diaphragm may at least partially define a third volume. A third valve plug may be coupled to the third diaphragm, and a third valve seat may be formed in a third central aperture of the second module that is in fluid communication with the second volume within the pneumatic cylinder. A third spring may be disposed within the third volume that biases the third valve plug into sealing engagement with the third valve seat such that the third poppet valve is normally closed. The fourth poppet valve may include a fourth diaphragm circumferentially secured to the first module, and the fourth diaphragm may at least partially define a fourth volume. A fourth valve plug may be coupled to the fourth diaphragm, and a fourth valve seat may be formed in a fourth central aperture in the second module that is in fluid communication with the second volume within the pneumatic cylinder. A fourth spring may be disposed within the fourth volume that biases the fourth valve plug into sealing engagement with the fourth valve seat such that the fourth poppet valve is normally closed.
In accordance with another exemplary aspect of the present invention, the third poppet valve may be maintained in the closed position by pressurized fluid within the third volume, and the fourth poppet valve may be maintained in the closed position by pressurized fluid within the fourth volume.
In accordance with yet another exemplary aspect of the present invention, a method of operating a pneumatic cylinder includes providing a supply of pressurized fluid. The method may further include providing a first control valve, and the first control valve may include a first supply port, a second supply port, a first exhaust port in fluid communication with the atmosphere, a second exhaust port in fluid communication with the atmosphere, and a supply port that is operatively coupled to the supply. The method may also include providing a first module having a first normally closed poppet valve and a second normally closed poppet valve. The method may further include providing a second module comprising a third normally closed poppet valve and a fourth normally closed poppet valve. The first work port of the first control valve may be operatively coupled to both the second poppet valve of the first module and the third poppet valve of the second module, wherein the second and third poppet valves are opened and closed by pressurized fluid flowing through the first work port. Additionally, the second work port of the first control valve may be operatively coupled to the first poppet valve of the first module and the fourth poppet valve of the second module, wherein the first and fourth poppet valves are opened and closed by pressurized fluid flowing through the second work port. The supply may be operatively coupled to the second poppet valve of the first module such that when the second poppet valve is in an open position and the first poppet valve is in a closed position, pressurized fluid is provided to a first volume within a pneumatic actuator, resulting in a translation of the pneumatic actuator in a first direction. Finally, the supply may be operatively coupled to the fourth poppet valve of the second module such that when the fourth poppet valve is in an open position and the third poppet valve is in a closed position, pressurized fluid is provided to a second volume within the pneumatic actuator, resulting in a translation of the pneumatic actuator in a second direction that is opposite the first direction.
In accordance with one more exemplary aspect of the present invention, the first poppet valve of the first module may be operatively coupled to an exhaust port such that when the second poppet valve is closed and the first poppet valve is open, pressurized fluid from the first volume of the pneumatic actuator can vent through the exhaust port. The third poppet valve of the second module may be operatively coupled to an exhaust port such that when the fourth poppet valve is closed and the third poppet valve is open, pressurized fluid from the second volume of the pneumatic actuator can vent through the exhaust port.
In accordance with another exemplary aspect of the present invention, the first control valve may have a first position and a second position. In the first position, the first work port may be in communication with the first exhaust port and the second work port may be in fluid communication with the supply port. In the second position, the first work port may be in communication with the supply port and the second work port may be in fluid communication with the second exhaust port.
In accordance with a further exemplary aspect of the present invention, a second control valve and a third control valve may be provided, wherein each of the second and third control valves has a work port, an exhaust port operatively coupled to the atmosphere, and a supply port operatively coupled to the supply. The work port of each of the second and third control valves may be operatively coupled to the first control valve such that the second control valve moves the first control valve from the first position to the second position, and the third control valve moves the first control valve from the second position to the first position.
In accordance with another exemplary aspect of the present invention, the first control valve is a spool valve and the second and third control valves are pilot valves.
In accordance with still one more exemplary aspect of the present invention, the first poppet valve may include a first diaphragm circumferentially secured to the first module, and the first diaphragm may at least partially define a first volume. A first valve plug may be coupled to the first diaphragm. A first valve seat may be formed in a first central aperture of the first module that is in fluid communication with the first volume within the pneumatic cylinder. A first spring may be disposed within the first volume biases the first valve plug into sealing engagement with the first valve seat such that the first poppet valve is normally closed. The second poppet valve may include a second diaphragm circumferentially secured to the first module, and the second diaphragm may at least partially define a second volume. A second valve plug may be coupled to the second diaphragm. A second valve seat may be formed in a second central aperture of the first module that is in fluid communication with the first volume within the pneumatic cylinder. A second spring may be disposed within the second volume biases the second valve plug into sealing engagement with the second valve seat such that the second poppet valve is normally closed. The third poppet valve may include a third diaphragm circumferentially secured to the second module, and the third diaphragm may at least partially define a third volume. A third valve plug may be coupled to the third diaphragm. A third valve seat may be formed in a third central aperture of the second module that is in fluid communication with the second volume within the pneumatic cylinder. A third spring may be disposed within the third volume biases the third valve plug into sealing engagement with the third valve seat such that the third poppet valve is normally closed. The fourth poppet valve may include a fourth diaphragm circumferentially secured to the second module, and the fourth diaphragm may at least partially define a fourth volume. A fourth valve plug may be coupled to the fourth diaphragm. A fourth valve seat may be formed in a fourth central aperture of the second module that is in fluid communication with the second volume within the pneumatic cylinder. A fourth spring may be disposed within the fourth volume biases the fourth valve plug into sealing engagement with the fourth valve seat such that the fourth poppet valve is normally closed.
In accordance with yet another exemplary aspect of the present invention, the first poppet valve may be maintained in the closed position by pressurized fluid within the first volume, the second poppet valve may be maintained in the closed position by pressurized fluid within the second volume, the third poppet valve may be maintained in the closed position by pressurized fluid within the third volume, and the fourth poppet valve may be maintained in the closed position by pressurized fluid within the fourth volume.
As illustrated in
A second module 42, illustrated in
As shown in
As illustrated in
Referring again to
Still referring to
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As previously explained, the components described above are intended to be modular, and may be interchanged as required for a specific application. Accordingly, the operation of the poppet valve assembly 10 will now be described for several, but not all, of the possible applications.
When it is desired to achieve 3/2 functionality in the poppet valve assembly 10, as shown in
When the pilot valve 58 is in the first position (the de-energized state), as shown in
When the pilot valve 58 is in the second position (the energized state), as shown in
One having ordinary skill in the art would recognize that, in the 3/2 configuration described above, the pneumatic actuator 26 can only be moved between two positions: a first position in which the actuator arm 120 is fully extended from the body 118 and a second position in which the actuator arm 120 is fully retracted into the body 118. One having ordinary skill in the art would additionally recognize that the 3/2 configuration described above may be achieved by other combinations of pilot and shuttle valves. For instance, the first poppet valve 18 may be operatively coupled to the pilot valve 58 instead of the shuttle valve 60, and the second poppet valve 20 may be operatively coupled to shuttle valve 60 instead of the pilot valve 58 to achieve 3/2 functionality.
When it is desired to achieve 5/2 functionality in the poppet valve assembly 10, both the first module 16 and the second module 42 may be disposed within the central bore 14 of the housing 12, as shown in
When the pilot valve 58 is in the first position (the de-energized state), as shown in
Also in the first position, as shown in
When the pilot valve 58 is in the second pilot position (the energized state), as shown in
Also in the second pilot position, as shown in
When it is desired to achieve 5/2 “fail last” functionality in the poppet valve assembly 10, as shown in
When the first pilot valve 58 is de-energized, as shown in
When it is desired to achieve 5/3 “center block” functionality in the poppet valve assembly 10, as shown in
When the first pilot 58 is energized and the second pilot 58′ is de-energized, as shown in
When both the first pilot 58 and the second pilot 58′ are de-energized (i.e., when both of the pilot work ports 116, 116′ are in fluid communication with both of the pilot supply ports 110, 110′) as shown in
When it is desired to achieve 5/3 “center exhaust” functionality (not shown in the figures), the poppet valve assembly 10 may be configured for the 5/3 “center block” functionality, as previously described. However, when both the first pilot 58 and the second pilot 58′ are energized, both of the pilot work ports 116, 116′ are in fluid communication with both of the pilot supply ports 110, 110′. Thus, when both pilots 58, 58′ are energized, the actuator arm 120 of the pneumatic actuator 26′ “freezes,” and can be maintained in any position between a first position in which the actuator arm 120 is fully extended from the body 118 and a second position in which the actuator arm 120 is fully retracted into the body 118.
While various embodiments have been described above, this disclosure is not intended to be limited thereto. Variations can be made to the disclosed embodiments that are still within the scope of the appended claims. For example, the poppet ports may be connected to pilot valves or shuttle valves other than those disclosed. For instance, in the 5/3 “center block” configuration, the first poppet pneumatic line 136a may connect the first poppet port 38a to the first pilot work port 116 instead of the second pilot work port 116′, the second poppet pneumatic line 136b may connect the second poppet port 38b to the second pilot work port 116′ instead of the first pilot work port 116, the third poppet pneumatic line 136c may connect the third poppet port 38c to the second pilot work port 116′ instead of the first pilot work port 116, and the fourth poppet pneumatic line 136d may connect the fourth poppet port 38d to the first pilot work port 116 instead of the second pilot work port 116′. Moreover, although a single supply 32 of pressurized fluid has been disclosed, the supply 32 of pressurized fluid may be comprised of several sources of pressurized fluid.
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| Entry |
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| Number | Date | Country | |
|---|---|---|---|
| 20120260993 A1 | Oct 2012 | US |
| Number | Date | Country | |
|---|---|---|---|
| 61470993 | Apr 2011 | US |
