Patent Description:
Embodiments disclosed herein relate to valves and, more particularly, to a pressure regulation system associated with an actuated valve.

Bleed systems, such as those for aircraft, generally involve taking compressed air from an engine, and converting it to various temperatures and pressures suitable for one or more uses. Pressure is usually managed through one or more bleed control valves, such as a butterfly valve for example. Depending on the configuration of the aircraft, these bleed control valves are generally controlled pneumatically. <CIT> relates to valve systems and more particularly starter valve systems for gas turbine engines. <CIT> relates to airflow control. <CIT> relates to a control valve. <CIT> relates to equipment used on aircraft to deliver compressed air from the power source.

According to an embodiment, an airflow control system is provided as claimed in claim <NUM>.

In addition to one or more of the features described above, or as an alternative, in further embodiments the digital controller is configured to trim the pressure within the flow control duct relative to the regulation pressure set point.

In addition to one or more of the features described above, or as an alternative, in further embodiments the valve actuator includes a piston and translation of the piston rotates the valve disk.

The pneumatic controller includes a lever and a second valve, wherein the lever is rotatable to adjust a position of the second valve in response to the pressure within the flow control duct downstream of the valve.

In addition to one or more of the features described above, or as an alternative, in further embodiments when the pressure within the flow control duct downstream of the valve disk is less than the regulation pressure set point, the second valve is closed.

In addition to one or more of the features described above, or as an alternative, in further embodiments when the pressure within the flow control duct downstream of the valve disk is greater than the regulation pressure set point, the second valve is open.

The lever has a preload, and the preload of the lever is equal to the regulation pressure set point.

A biasing member is connected to the lever, and a biasing force of the biasing member is equal to the preload.

In addition to one or more of the features described above, or as an alternative, in further embodiments the airflow control system is on an aircraft.

According to another embodiment, an aircraft includes an environmental control system for conditioning air, a bleed air system for providing a flow of air to the environmental control system, and an airflow control system arranged between the bleed air system and the environmental control system. The airflow control system includes a pneumatic controller and a digital controller. The pneumatic controller and the digital controller are independently operable to regulate a pressure of the flow of air provided to the environmental control system.

In addition to one or more of the features described above, or as an alternative, in further embodiments the pneumatic controller is operable to maintain the pressure of the flow of air at or below a regulation pressure set point.

In addition to one or more of the features described above, or as an alternative, in further embodiments the digital controller is operable to adjust the pressure of the flow of air to equal a digital set point, the digital set point being less than the regulation pressure set point.

According to another embodiment, a method of regulating a pressure of a flow of air is provided as claimed in claim <NUM>.

In addition to one or more of the features described above, or as an alternative, in further embodiments comprising adjusting a position of the valve controlling the flow of air in response to determining that the parameter of the portion of the flow of air exceeds the regulation pressure set point.

Adjusting the position of the valve controlling the flow of air in response to determining that the parameter of the portion of the flow of air exceeds the regulation pressure set point includes rotating a lever of the pneumatic controller to open a second valve, the second valve being operably coupled to the valve.

In addition to one or more of the features described above, or as an alternative, in further embodiments comprising sensing the parameter of the portion of the flow of air and communicating the sensed parameter to a digital controller, wherein the digital controller is operable to compare the parameter to the digital set point.

In addition to one or more of the features described above, or as an alternative, in further embodiments the parameter is pressure.

In addition to one or more of the features described above, or as an alternative, in further embodiments the parameter is flow rate.

In addition to one or more of the features described above, or as an alternative, in further embodiments adjusting the position of a valve controlling the flow of air in response to the comparison of the parameter and the digital set point includes commanding movement of a torque motor, the torque motor being operably coupled to the valve.

With reference to the accompanying drawing, like elements are numbered alike:
The Figure is a schematic diagram of a valve and a pressure regulation system of the valve according to an embodiment.

A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figure.

An example of an airflow control system is illustrated in <FIG>. The airflow control system <NUM>, as shown, includes a valve <NUM> having a valve housing <NUM>, valve disk <NUM>, and shaft <NUM>. In the illustrated, non-limiting embodiment, the valve is a butterfly-type valve. However, it should be understood that any suitable type of valve is within the scope of the disclosure. The valve housing <NUM> defines a flow control passage having a first portion <NUM> upstream of the valve disk <NUM> and a second portion <NUM> downstream of the valve disk <NUM>. The valve disk <NUM> is a closure element rotatable within the flow control passage defined by the housing <NUM> to manage flow between the upstream portion <NUM> and the downstream portion <NUM> of the flow passage.

A valve actuator <NUM>, which can be driven by a fluid, such as air, is operable to rotate the valve disk <NUM> between a plurality of positions. The valve actuator <NUM> may rotate the valve disk <NUM> over a range between a fully closed position and a fully open position to regulate pressure in the downstream portion <NUM> of the flow passage. Operation of the valve actuator <NUM> can be managed, for example, using a digital controller <NUM> and/or a pneumatic controller <NUM>. A torque motor <NUM> is operable to adjust a size of one or more flow restrictions in accordance with a command from the digital controller <NUM> to open or close the valve <NUM>. Further, the pneumatic controller <NUM>, which functions as a pressure regulator, is similarly operable to close or open the valve <NUM>.

The airflow control system <NUM> may form part of a vehicle. For example, in an embodiment, the airflow control system <NUM> is part of an aircraft bleed air system and the valve <NUM> is a pressure regulating and shutoff valve arranged within a bleed air manifold. Air from a gas turbine engine or an auxiliary unit of the aircraft, illustrated schematically at <NUM>, is provided to the upstream portion <NUM> of the flow passage, and the air within the downstream portion <NUM> of the flow passage may be provided to an environmental control system (ECS) of an aircraft, illustrated schematically at <NUM>. However, it will be appreciated that airflow control system <NUM> is not necessarily limited to aircraft bleed systems or even to an aircraft, and thus can be adapted to find use in numerous other airflow control applications.

The pneumatic controller or pressure regulator <NUM> in conjunction with the torque motor <NUM> is operable to control the regulation pressure of the valve <NUM>. The pneumatic controller <NUM> has a fixed regulation set point which can be trimmed or adjusted using the torque motor <NUM>. In the illustrated, non-limiting embodiment, the pneumatic controller <NUM> includes a cantilevered lever <NUM> having a biasing member <NUM>, such as a coil spring for example, connected to the lever <NUM> adjacent a first end and a valve <NUM>, such as a poppet valve for example, connected to the lever <NUM> adjacent to a second end thereof.

In an embodiment, the pneumatic controller <NUM> has a fixed regulation pressure set point. This regulation pressure set point is defined by the preload applied to the lever <NUM>. In the illustrated, non-limiting embodiment, the preload applied to the lever is equal to the biasing force of the biasing member <NUM>. Accordingly, it is only when the pressure applied to the lever <NUM> exceeds the regulation pressure set point that the lever <NUM> will pivot about its axis and adjust a position of the poppet valve <NUM>.

In an embodiment, the pneumatic controller <NUM> additionally includes a lag chamber <NUM> connected to the downstream portion <NUM> of the flow passage via a laminar restrictor or orifice <NUM>. This connection results in 1ag compensation which provides for stable operation of the pneumatic controller <NUM>. It should be understood that a pneumatic controller <NUM> having another configuration is also contemplated herein.

The functional schematic of the system <NUM> shown in the Figure, illustrates how these components are interconnected. In the illustrated, non-limiting embodiment, the pneumatic controller <NUM> is fluidly coupled to the downstream portion <NUM> of the flow passage. Accordingly, the pressure within the downstream portion <NUM> of the flow passage exerts a force on the lever <NUM> of the pneumatic controller <NUM>. The poppet valve <NUM> is fluidly connected to a first chamber <NUM> arranged adjacent a first side of the movable piston <NUM> of the valve actuator <NUM>. Movement of the lever <NUM> is used to control a position of the poppet valve <NUM> and therefore to control the servo pressure acting on the piston <NUM> of the valve actuator <NUM> operably coupled to the pressure regulating valve <NUM>.

When the pressure within the downstream portion <NUM> of the flow passage is below the regulation pressure set point of the pneumatic controller <NUM>, the preload on the lever <NUM> positions the lever <NUM> such that the poppet valve <NUM> is closed. When the poppet valve <NUM> is closed, the piston <NUM> of the valve actuator <NUM> is configured to move the valve disk <NUM> to a fully open position. When the pressure within the downstream portion <NUM> of the flow passage exceeds the regulation pressure set point, the pressure acting on the first end of the lever <NUM> of the pneumatic controller <NUM> will oppose and exceed the biasing force of the biasing member <NUM>, causing the lever <NUM> to rotate and open the poppet valve <NUM>. When the poppet valve <NUM> is open, the servo pressure acting on the piston <NUM> drops, causing the piston <NUM> to translate, thereby closing the valve <NUM>. Accordingly, the pneumatic controller <NUM> coupled to the flow passage and the valve actuator <NUM> forms a loop that continuously adjusts the servo pressure (and hence the position of the valve disk <NUM>) to maintain the regulated pressure within the downstream portion <NUM> of the flow passage at the desired set-point.

In an embodiment, a shutoff device <NUM>, such as a solenoid for example, is fluidly connected to the passage connecting the poppet valve <NUM> and the valve actuator <NUM>. In such embodiments, the shutoff device <NUM> may be operated to adjust the servo pressure, within the conduit. Operation of the shutoff device <NUM> provides a manual override with respect to the pneumatic controller <NUM> and causes the poppet valve <NUM> to shut.

The torque motor <NUM> provides secondary control of the servo pressure independently from the pneumatic controller <NUM>. In an embodiment, the torque motor <NUM> is operable to adjust a flow to the valve actuator <NUM> to open or close the valve <NUM> in response to a command generated by the digital controller <NUM>. The torque motor <NUM> is fluidly coupled to the first chamber <NUM> of the valve actuator <NUM> via a first flow path <NUM> that overlaps with the flow path extending from the pneumatic controller <NUM>. The torque motor <NUM> is additionally fluidly coupled to a second chamber <NUM> of the valve actuator <NUM> arranged adjacent an opposite side of the piston <NUM> via a second flow path <NUM>. Relative pressure within the first and second flow paths are controller to drive rotation of the valve disk <NUM> to a desired position.

In an embodiment, the torque motor <NUM> is configured to provide full digital control of the regulation pressure when the regulation pressure is below the regulation pressure set point of the pneumatic controller <NUM>. The digital controller <NUM>, in combination with the torque motor <NUM>, can digitally trim the pressure in the bleed manifold.

As shown, at least one sensor <NUM> is operable to detect a parameter within the downstream portion <NUM> of the flow passage. In an embodiment, the sensor <NUM> is configured to detect the regulation pressure within the downstream portion <NUM> of the flow passage. Alternatively, or in addition, the sensor <NUM> is configured to detect the flow rate within the downstream portion of the flow passage. The measurements sensed by the sensor <NUM> is communicated from the sensor <NUM> to the digital controller <NUM>. The digital controller <NUM> is configured to process the signal and compare the sensed data to a selected digital pressure set-point. In response to this comparison, the digital controller <NUM> sends a signal to the torque motor <NUM> commanding operation to either increase, decrease or maintain the current pressure regulation.

In an embodiment, the digital set-point is defined in software, such as an algorithm, that is embedded in or accessed by the digital controller <NUM>. Further, the digital set-point may be based on the system needs, and therefore can be fixed or variable based on the design of the system and the control software. Pneumatic controllers, such as controller <NUM> for example, have inherent inaccuracy to their set-point due to friction in the actuator. In an embodiment, the digital controller <NUM> is configured to compensate for this inaccuracy by sensing the manifold pressure and adjusting the digital set-point. Accordingly, if the pneumatic controller <NUM> is regulating high due to friction, the digital controller <NUM> will sense the high pressure and lower the digital set-point. Similarly, if the pneumatic controller <NUM> is regulating low due to friction, the digital controller <NUM> will increase the digital set-point as compensation.

In addition, in embodiments having multiple sources (engines) connected to a single manifold (each source having its own pressure regulation control), the digital controller <NUM> may be configured to calculate the required digital pressure set-point(s) required for each valve in order to extract equal air flow from each source. In such embodiments, the digital set-point(s) permit correcting physical and operational differences between the sources and the pneumatic controller set point. Alternatively, or in addition, the digital set-point may be adjustable based on the required input pressure/flow needed for systems downstream of the manifold.

An airflow control system as illustrated and described herein allows for greater control of the pressure of a flow of bleed air provided to an environmental control system.

Claim 1:
An airflow control system comprising:
a valve including a valve disk (<NUM>) rotatable within a flow control duct;
a valve actuator (<NUM>) including a movable piston connected to the valve disk, wherein the valve actuator (<NUM>) is operable to adjust a position the valve disk;
a sensor (<NUM>) operable to detect a parameter within the flow control duct, downstream of the valve disk;
a pneumatic controller (<NUM>) configured to regulate a pressure within the flow control duct downstream of the valve disk, wherein the pneumatic controller is operable to adjust the position of the valve disk when the pressure within the flow control duct downstream of the valve disk exceeds a regulation pressure set point, the pneumatic controller being fluidly coupled to a first chamber arranged adjacent to a first side of the movable piston of the valve actuator;
a torque motor (<NUM>) fluidly connected to the valve actuator and fluidly coupled to a second chamber of the valve actuator arranged adjacent a second, opposite side of the piston; and
a digital controller (<NUM>) operably coupled to the torque motor, wherein the digital controller is configured to regulate the pressure within the flow control duct downstream of the valve disk independently from the pneumatic controller when the pressure downstream of the valve disk is below the regulation pressure set point, the digital controller being operable to command the torque motor (<NUM>) to either increase, decrease or maintain the pressure regulation in response to a comparison of the detected parameter and a digital set point;
wherein the pneumatic controller includes a cantilevered lever (<NUM>) and a second valve, wherein the lever is rotatable to adjust a position of the second valve in response to the pressure within the flow control duct downstream of the valve,
wherein the lever has a preload, and the preload of the lever is equal to the regulation pressure set point, and wherein a biasing member (<NUM>) is connected to the lever, and a biasing force of the biasing member is equal to the preload.