Patent Application
20250041633
The disclosure relates to gas regulators for a breathing apparatus.
Pressure regulating devices are essential components used in various industries to control and maintain the pressure of fluids or gases within a desired range. For example, in breathing apparatuses a pressure regulator may be used to reduce gas pressure from a supply to the mask of a user for breathing.
The disclosure describes systems and techniques for providing stable fluid supply from an outlet of a fluid regulator to a breathing device. A pressurized fluid supply may connect to the inlet of the regulator, while the outlet of the fluid supply may be connected to a breathing device that requires a flow of the fluid at a different pressure than the supply, e.g., a breathing mask.
Turbulent flow of a fluid at the outlet of a regulator can prevent accurate measurement of the fluid pressure at the outlet of the regulator, hindering effective and safe operation of the regulator, as well as hindering the operation of devices downstream from the regulator. In order to ensure consistent static pressure sensed by the regulator, and to ensure sufficient fluid flow to downstream breathing devices, the regulator may include a boost tube within an outlet portion of the regulator configured to laminarize turbulent fluid flow within the outlet portion of the regulator.
In some examples, a breathing system includes a pressurized fluid supply, a downstream breathing device, and a fluid regulator. The fluid regulator includes: an inlet in fluid connection with the fluid supply, wherein the fluid supply supplies fluid at a first pressure to the inlet; an outlet in fluid connection with a downstream breathing device, wherein the fluid is at a second pressure at the outlet, and wherein the second pressure is lower than the first pressure; and a boost tube disposed within an outlet portion of the fluid regulator. The boost tube includes: a body defining a length; and a plurality of apertures extending through the length of the body and configured to reduce turbulence of the fluid flowing from the outlet to the downstream breathing device.
In some examples, a fluid regulator includes: an inlet in fluid connection with a fluid supply, wherein the fluid supply supplies fluid at a first pressure to the inlet; an outlet in fluid connection with a downstream breathing device, wherein the fluid is at a second pressure at the outlet, and wherein the second pressure is lower than the first pressure; and a boost tube disposed within an outlet portion of the fluid regulator. The boost tube includes: a body defining a length; and a plurality of apertures extending through the length of the body and configured to reduce turbulence of the fluid flowing from the outlet to the downstream breathing device.
The details of one or more examples of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims.
The disclosure describes a boost tube of a fluid regulator that includes a plurality of apertures through its length. In a fluid system, a fluid regulator controls and maintains the pressure of a fluid at the regulator's outlet within a desired range, given a supply pressure at the regulator's inlet. By adjusting the flow rate or restricting the fluid flow, the regulator can maintain a constant and controlled pressure at the outlet, regardless of variations in the input pressure.
For example, an inlet of the regulator may be connected to a pressurized fluid supply tank, while an outlet of the regulator may be in fluid connection with a breathing mask (e.g., for pilots, divers, etc.). The regulator may maintain a breathable pressure of air to the breathing mask despite depletion of pressure in the supply tank. In a typical fluid regulator, a channel (e.g., a sense port) may extend from the outlet of the regulator to the diaphragm of the regulator. The channel may be located within an outlet portion of the regulator such that the pressure in the channel is representative of the static pressure at the outlet of the regulator. The regulator may adjust the amount of fluid flowing through the regulator in response to a pressure difference across the diaphragm, where the pressure difference experienced by the diaphragm is based in part on the static pressure exerted on the diaphragm through the channel from the outlet. In this way, the regulator may maintain a constant pressure at the outlet of the regulator given changes in fluid supply pressure at the inlet of the regulator and changes in fluid demand downstream of the regulator outlet.
As fluid flows from the interior of the regulator to the outlet, restrictions and/or tortious paths through the regulator may create turbulence in the fluid flow. Turbulence in the fluid flow may prevent accurate measurement, or promote inconsistent measurement, of the fluid pressure at the outlet of the regulator, hindering effective and safe operation of the regulator, as well as hindering the operation of devices downstream from the regulator. For example, a breathing mask for a user may be unable to draw sufficient air (or other gas containing oxygen, e.g., oxygen or oxygen-enriched air) when the flow of air through the system is turbulent. In order to ensure consistent static pressure sensed by the regulator through the sense port, and to ensure sufficient fluid flow to downstream breathing devices, the regulator may include a boost tube within an outlet portion of the regulator configured to laminarize turbulent fluid flow within the outlet portion of the regulator.
The boost tube may include a substantially cylindrical restrictive orifice of a particular length within an outlet portion of the regulator, through which the fluid must flow before being sensed through the sense port or progressing to a downstream breathing device. As fluid flows through the boost tube, the flow becomes smoother and more laminar, resulting in more consistent pressure downstream. In order to laminarize the flow sufficiently for effective operation of the components of the breathing system, the fluid must flow a sufficient distance through the restrictive orifice of the boost tube, and a sufficient distance through piping downstream of the boost tube before reaching any downstream breathing devices. Otherwise, the flow may not be smooth or stable enough for effective operation of the downstream breathing device.
These required distances increase the length of both the regulator and the downstream piping in breathing systems. The increase in length may be disadvantageous in situations where space and weight is a valuable commodity, e.g., in breathing systems for pilots in the cockpit of an aircraft, or in breathing systems for divers who must carry their equipment while they swim. A reduction in length of the components of the breathing system may reduce the cost of materials for the system, reduce the energy cost to transport the breathing system, and reduce the space profile of the system.
To that end, this disclosure describes systems including a boost tube with a plurality of apertures through a length of the boost tube. By including a plurality of apertures in the boost tube, rather than just a single orifice, the boost tube may sufficiently smooth the fluid flow over a much shorter distance. This may allow the boost tube to occupy a smaller profile within the regulator, as well as reduce the length of piping necessary downstream of the boost tube to ensure smooth fluid flow and effective operation of downstream breathing devices. In this way, the boost tube described by this disclosure may reduce the total size of breathing systems that include the boost tube of this disclosure. In turn, this may reduce the amount of material necessary to construct such systems, reduce the cost of such systems, reduce the energy required to transport such systems, and increase the effectiveness and safety of the devices within the system.
Fluid supply 102 may supply pressurized fluid to inlet 108. For example, fluid supply 102 may include one or more compressed gas/liquid cylinders, e.g., compressed air, or compressed oxygen. In some examples, fluid supply 102 may include more than just a compressed cylinder. For example, fluid supply 102 may include an onboard oxygen generation system or a liquid oxygen system. The pressure of the fluid inside the system at inlet 108 may be referred to as the supply pressure.
Downstream breathing device 106 may include one or more devices that require pressurized fluid for operation. For example, downstream breathing device 106 may include a breathing mask. In some examples downstream breathing device 106 may include a pilot mask, a diving mask, a respirator, a mask in a self-contained breathing apparatus, or any other type of breathing mask. The pressure of the fluid necessary for effective operation of downstream breathing device 106 may be less than the supply pressure of the fluid at inlet 108. In examples where downstream breathing device 106 is a breathing mask, the breathing mask may be configured to receive a fluid at or near a comfortable breathing pressure, e.g., atmospheric pressure. Fluid regulator 104 may be configured to reduce the pressure of the fluid at inlet 108 to a lower pressure at outlet 110 suitable for the operation of downstream breathing device 106.
Fluid regulator 104 may include an internal mechanism for adjusting the amount of fluid that flows through fluid regulator from inlet 108 to outlet 110. By restricting the flow of fluid through fluid regulator 104, fluid regulator 104 may provide fluid at outlet 110 that is at a lower pressure than fluid at inlet 108. The internal mechanism may include components that adjust the amount of fluid flowing through fluid regulator 104 in response to a sensed pressure difference between a reference setpoint and outlet 110. In this way, even if the pressure from fluid supply 102 changes, or fluid demand from downstream breathing device 106 changes, fluid regulator 104 can maintain a steady supply of fluid at a specified pressure from outlet 110 to downstream breathing device 106.
For example, fluid regulator 104 may include an internal diaphragm, where a pressure difference across the diaphragm dictates how much fluid flow is restricted through fluid regulator 104. Pressure on one side of the diaphragm may be indicative of a delivery pressure, and pressure on the other side of the diaphragm may be indicative of pressure at outlet 110. In some examples, fluid regulator 104 does not include a diaphragm, but includes another mechanism for sensing pressure differences and adjusting fluid flow within fluid regulator 104 based on the sensed pressure differences. In some examples, fluid regulator 104 may include electronic pressure sensors and a solenoid used to restrict fluid flow based on a sensed pressure difference. In some examples, fluid regulator 104 may include any other mechanism known in the art for adjusting fluid flow through fluid regulator 104 in response to a sensed pressure difference between the reference setpoint and outlet 110.
Fluid regulator 104 may constantly adjust fluid flow through fluid regulator 104 in response to supply pressure changes and changes in demand from downstream breathing device 106. For example, as fluid leaves fluid supply 102 and is used by components of system 100, the pressure of fluid in fluid supply 102, and subsequently the pressure of fluid at inlet 108, may decrease. When downstream breathing device 106 is in use, downstream breathing device 106 may require a steady flow of fluid, subsequently decreasing fluid pressure at outlet 110. In some examples where system 100 is a breathing system, regulator 104 may change the target outlet pressure in order to maintain a physiological environment for the user of the breathing mask. For example, as altitude increases in an aircraft, the outlet pressure maintained by regulator 104 may be increased.
Although regulator 104 and system 100 have been described primarily with reference to breathing systems, it is understood that regulator 104 may be used in other breathing systems where a regulator is used to reduce the pressure from an inlet to an outlet and smooth outlet fluid flow is desirable.
To sense the pressure at outlet 210, sense port 222 may extend from outlet 210 to the mechanism used by the fluid regulator to control fluid flow through the regulator. Sense port 222 may be located near outlet 210 to effectively sense the fluid pressure at outlet 210. However, the fluid in outlet portion 204 may be turbulent due to the restrictions and tortious paths within the fluid regulator. The example of
Outlet portion 204 includes boost tube 216. Boost tube 216 may be configured to reduce the turbulence of the fluid flowing from outlet portion 204 to downstream breathing devices. Boost tube 216 may be disposed within outlet portion 204 within the fluid path just before the fluid reaches outlet 210. In this way boost tube 216 smooths the flow of fluid before it exits the fluid regulator. As a result of this smoothing, sense port 222 may measure a consistent static pressure of the fluid within outlet portion 204 at the downstream end of boost tube 216. For example, the entrance to the channel that defines sense port 222 may be disposed within outlet portion 204 such that fluid must travel 180 degrees from the downstream end of boost tube 216 to enter the channel. A total fluid pressure in the direction of flow of the fluid may be greater than the static pressure, allowing the regulator to more consistently meet the changing fluid demands of downstream breathing devices. In this way, the regulator may maintain a constant static pressure at outlet 210 of the regulator and provide sufficient fluid to downstream breathing devices given changes in fluid supply pressure at the inlet of the regulator and changes in fluid demand downstream of outlet 210.
Boost tube 216 may include a body defining length L, and a plurality of apertures 218 extending through length L of the body. Boost tube 216 may smooth the fluid flow by forcing fluid in outlet portion 204 to pass through apertures 218 before progressing downstream. By including the plurality of apertures 218, boost tube 216 may smooth the fluid flow over a shorter length L than if boost tube 216 had only a single aperture. In some examples, length L may be three to five times the length of a diameter of boost tube 216 (e.g., first diameter D1 of
Outlet portion 204 may also include vent 220. Vent 220 may be a pressure relief valve or other safety feature designed to vent pressure in a failure scenario (e.g., diaphragm, pressure relief disk, etc.). For example, if the regulator fails to sufficiently decrease the fluid pressure from the inlet to outlet 210, pressure within outlet portion 204 at outlet 210 may become too great and damage downstream breathing devices or harm people using downstream breathing devices. In order to prevent damage to downstream breathing devices, vent 220 may be configured to release fluid from outlet portion 204 to the surrounding environment at preset pressures. Turbulent flow of the fluid can also prevent effective operation of vent 220. If the local pressure sensed at vent 220 is too low, it may not relieve pressure in outlet portion 204 before the pressure damages downstream breathing devices. If the pressure sensed at vent 220 is too high, it may vent fluid to the surroundings at the expense of necessary fluid flow to downstream breathing devices for the effective operation of the downstream breathing devices. Inconsistent pressure at vent 220 can also decrease the life of vent 220, as repeated opening and closing of vent 220 may wear out vent 220. Because boost tube 216 smooths the fluid flow, boost tube 216 ensures consistent and effective operation of vent 220.
In some examples, vent 220 may be disposed in outlet portion 204 at an opposite side of boost tube 216 from sense port 222. In some examples, vent 220 may be disposed in outlet portion 204 on the same side of boost tube 216 as sense port 222.
Boost tube 316 may include a plurality of apertures configured to reduce the turbulence of fluid 312 flowing from outlet 310 to a downstream breathing device. In the example of
Vent 320 may be disposed closer to outlet 310 than downstream end 330 of boost tube 316. As discussed above, boost tube 316 smooths the fluid flow through outlet portion 304, ensuring effective operation of vent 320. In the case of a failure event, the faster that vent 320 can react to an overpressure within outlet portion 304, the more likely vent 320 is to prevent damage to downstream breathing devices. According to the techniques of the present disclose, and because boost tube 316 is able to smooth the flow over a shorter distance, fluid 312 flowing from downstream end 330 of boost tube 316 may only need to travel 90 degrees in order to pass through entrance 326 of vent 320. In examples where boost tube 316 is longer, fluid may need to travel 180 degrees from downstream end 330 of boost tube 316 to entrance 326 of vent 320, delaying the reaction time of vent 320 to overpressure events. Vent 320 may be any pressure relief device.
In the example of
Boost tube 416 may define a substantially cylindrical shape, wherein a cross-section of the body of boost tube 416 defines a substantially circular profile. The perimeter of the substantially circular profile may define a first diameter D1. Apertures 418 may include at least two apertures arranged equidistant from one another around a circle with diameter D2. The circle may be concentric with the profile of boost tube 416, and second diameter D2 may be smaller than first diameter D1. In some examples, a body of boost tube 416 may define a length (e.g., length L of
In the example of
In some examples, boost tube 416 may be constructed partially or entirely of metal, for example, aluminum. In some examples, boost tube 416 may be formed partially or entirely from a polymer.
Boost tube 516 may define a substantially cylindrical shape, wherein a cross-section of the body of boost tube 516 defines a substantially circular shape. Boost tube 516 may include a plurality of apertures 518A-N, wherein at least one of the plurality of apertures 518A-N is disposed at a center of the substantially circular shape. In the example of
Boost tube 516 may include a chamfered, rounded, or otherwise contoured inlet 528 to help efficiently smooth the fluid flow through boost tube 516 without causing excessive drag. In the example of
Adapter 632 may be configured to attach boost tube 616 to existing attachment points within regulator 604 to allow shorter boost tube 616 to operate in legacy regulators. For example, adapter 632 may include one or more legs 634 configured to attach to an interior of regulator 604. In some examples, boost tube 616 attaches inside adapter 632. In some examples, adapter 632 and legs 634 are integrated into boost tube 616. Boost tube 616 may define a body defining a length (e.g., length L of
In some examples, adapter 632 defines a substantially cylindrical shape with boost tube 616 disposed within the substantially cylindrical shape. In some examples, adapter 632 includes only legs 634 extending from boost tube 616 to the attachment points, such that fluid may flow perpendicular to longitudinal axis 636 along a length of adapter 632 downstream of boost tube 616. In this way, regulator 604 may see some of the benefits of having shorter boost tube 616 without including a shorter outlet portion itself, or being installed with shorter outlet piping/tubing. For example, fluid flowing out of boost tube 616 may only need to turn 90 degrees to enter a vent or other pressure relief device.
The following numbered examples demonstrate one or more aspects of the disclosure.
Example 1: A breathing system including: a pressurized fluid supply; a downstream breathing device; and a fluid regulator including: an inlet in fluid connection with the fluid supply, wherein the fluid supply supplies fluid at a first pressure to the inlet; an outlet in fluid connection with a downstream breathing device, wherein the fluid is at a second pressure at the outlet, and wherein the second pressure is lower than the first pressure; and a boost tube disposed within an outlet portion of the fluid regulator and including: a body defining a length; and a plurality of apertures extending through the length of the body and configured to reduce turbulence of the fluid flowing from the outlet to the downstream breathing device.
Example 2: The breathing system of example 1, wherein the boost tube further includes a chamfered inlet.
Example 3: The breathing system of example 1, wherein the boost tube further includes a rounded inlet.
Example 4: The breathing system of example 1, wherein a cross-section of the body of the boost tube defines a substantially circular profile with a first diameter, and wherein the plurality of apertures include at least two apertures arranged equidistant from one another around a circle concentric with the profile, wherein the circle has a second diameter smaller than the first diameter.
Example 5: The breathing system of example 1, wherein a cross-section of the body of the boost tube defines a substantially circular shape, and wherein at least one of the plurality of apertures is disposed at a center of the substantially circular shape.
Example 6: The breathing system of example 1, wherein the downstream breathing device includes a breathing mask.
Example 7: The breathing system of example 1, wherein the fluid regulator further includes an adapter attached to the boost tube, wherein the adapter includes one or more legs configured to attach the boost tube to the fluid regulator within the outlet portion.
Example 8: The breathing system of example 7 wherein the length of the body defines a longitudinal axis, and wherein the one or more legs extend from an end of the boost tube parallel to the longitudinal axis.
Example 9: The breathing system of example 1, wherein the boost tube defines a first end and a second end, wherein the second end is disposed nearer to the outlet than the first end; wherein the outlet portion further includes a pressure relief device in fluid connection with the boost tube, wherein an entrance to the pressure relief device is disposed nearer to the outlet than the second end of the boost tube.
Example 10: The breathing system of example 1, wherein the fluid regulator further includes a sense port in the outlet portion, wherein the boost tube is configured to maintain a static pressure at the sense port.
Example 11: A fluid regulator including: an inlet in fluid connection with a fluid supply, wherein the fluid supply supplies fluid at a first pressure to the inlet; an outlet in fluid connection with a downstream breathing device, wherein the fluid is at a second pressure at the outlet, and wherein the second pressure is lower than the first pressure; and a boost tube disposed within an outlet portion of the fluid regulator and including: a body defining a length; and a plurality of apertures extending through the length of the body and configured to reduce turbulence of the fluid flowing from the outlet to the downstream breathing device.
Example 12: The fluid regulator of example 11, wherein the boost tube further includes a chamfered inlet.
Example 13: The fluid regulator of example 11, wherein the boost tube further includes a rounded inlet.
Example 14: The fluid regulator of example 11, wherein a cross-section of the body of the boost tube defines a substantially circular profile with a first diameter, and wherein the plurality of apertures include at least two apertures arranged equidistant from one another around a circle concentric with the profile, wherein the circle has a second diameter smaller than the first diameter.
Example 15: The fluid regulator of example 11, wherein a cross-section of the body of the boost tube defines a substantially circular shape, and wherein at least one of the plurality of apertures is disposed at a center of the substantially circular shape.
Example 16: The fluid regulator of example 11, wherein the downstream breathing device includes a breathing mask.
Example 17: The fluid regulator of example 11, wherein the fluid regulator further includes an adapter attached to the boost tube, wherein the adapter includes one or more legs configured to attach the boost tube to the fluid regulator within the outlet portion.
Example 18: The fluid regulator of example 17, wherein the length of the body defines a longitudinal axis, and wherein the one or more legs extend from an end of the boost tube parallel to the longitudinal axis.
Example 19: The fluid regulator of example 11, wherein the boost tube defines a first end and a second end, wherein the second end is disposed nearer to the outlet than the first end; wherein the outlet portion further includes a pressure relief device in fluid connection with the boost tube, wherein an entrance to the pressure relief device is disposed nearer to the outlet than the second end of the boost tube.
Example 20: The fluid regulator of example 11, wherein the fluid regulator further includes a sense port in the outlet portion, and wherein the boost tube is configured to maintain a static pressure at the sense port.
Example 21: The fluid regulator of example 11, wherein a cross-section of the body of the boost tube defines a substantially circular profile with a diameter, wherein the length defined by the body of the boost tube is less than three times the diameter.
Various examples have been described. These and other examples are within the scope of the following claims.
