Evaporative fluid management canister for wound healing systems

Abstract

A canister for use with a wound treatment system includes a first compartment and a second compartment configured to receive and contain wound exudate, and an airflow pathway including a planar region positioned between the first and second compartments, an inlet extending from a first end of the planar region at an obtuse angle to the planar region, and an outlet at a second end of the planar region.

Description

Technical Field

[0001] Cross - reference to Related Applications This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 162,146, filed on March 17, 2021, the entire contents of which are incorporated herein by reference.

[0002] This disclosure generally relates to negative pressure wound therapy (NPWT) systems. More particularly, this disclosure relates to active or forced evaporation in the canister of an NPWT system.

Summary of the Invention

[0003] One implementation of the present disclosure is a canister for use with a wound treatment system. The canister includes a first compartment and a second compartment configured to receive and contain wound exudate, and an air flow path. The air flow path includes a planar region positioned between the first compartment and the second compartment, an inlet extending from a first end of the planar region at an obtuse angle with respect to the planar region, and an outlet at a second end of the planar region.

[0004] In some embodiments, the first compartment is separated from the air flow path by a first filter configured to allow water molecules to pass from the first compartment to the air flow path and prevent contaminants from passing from the first compartment to the air flow path. The first filter may include a polyurethane film. The canister may include a rigid structure defining the first and second compartments and formed of a thermoplastic polyurethane resin. This rigid structure is ultrasonically welded to the polyurethane film, the canister according to claim 4.

[0005] In some embodiments, the first filter includes a film having a high water vapor permeability. For example, the high water vapor transmission may be in the range of 2000 - 5000 g / m 2 / day.

[0006] In some embodiments, the inlet is cylindrical. The inlet may be formed to match the cross-sectional shape of the fan. The inlet may widen close to the planar region to reduce turbulence and back pressure in the airflow path.

[0007] In some embodiments, the canister includes a curved wall that provides a smooth transition from the inlet to a planar region. In some embodiments, the obtuse angle is in the range of 130° to 150°. In some embodiments, the inlet has a screw-type configuration configured to provide rotation of the airflow through it.

[0008] Another implementation of the present disclosure is a treatment system. The treatment system includes a dressing configured to cover and seal a wound site; a negative pressure source configured to draw negative pressure in the dressing so that wound exudate exits the dressing; and a canister configured to be in fluid communication with the dressing. The canister includes a first compartment and a second compartment configured to receive and retain wound exudate from the dressing, and an airflow path. The airflow path includes a planar region positioned between the first and second compartments, an inlet extending from the first end of the planar region at an obtuse angle to the planar region, and an outlet at the second end of the planar region. The treatment system also includes an air mover aligned with the inlet and configured to force air into the airflow path to facilitate the transport of moisture from wound exudate exiting the first and second components.

[0009] In some embodiments, the air mover is an axial fan, blower, or centrifugal fan. In some embodiments, the treatment system further includes a housing, in which the air mover and negative pressure source are installed. The canister is configured to be selectively and detachably coupled to the housing. The treatment system may also include a battery installed within the housing. The canister is configured to be selectively and detachably coupled to the housing.

[0010] In some embodiments, the treatment system also includes a controller configured to control the air mover to operate in a pulsing pattern.

[0011] In some embodiments, the treatment system also includes a tube connecting the dressing to the canister. The first and second compartments may be separated from the airflow path by a film material configured to allow water molecules to pass from the first and second compartments to the airflow path and to prevent contaminants from passing from the first and second compartments to the airflow path.

[0012] Another embodiment of the present disclosure is a method for manufacturing a canister for a wound healing device. The method includes providing a first rigid structure and a second rigid structure formed of a polyurethane resin, providing first and second filters formed of a polyether urethane film, ultrasonically welding the first rigid structure to the first filter, ultrasonically welding the second rigid structure to the second filter, and ultrasonically welding the first rigid structure to the second rigid structure such that a planar airflow path is defined between the first filter and the second filter.

[0013] In some embodiments, the method includes coupling a first wall to a first rigid structure such that a first section is defined by a first wall, a first rigid structure, and a first filter. The method may also include coupling a second wall to a second rigid structure such that a second section is defined by a second wall, a second rigid structure, and a second filter.

[0014] In some embodiments, the method includes configuring the second rigid structure such that it defines an inlet extending across the second rigid structure from a planar airflow path. The method may also include forming the first and second filters such that the first and second filters are configured to allow water molecules to pass across the first and second filters.

[0015] Those skilled in the art will understand that the summary is illustrative and not intended to be limiting in any way. Other aspects of the apparatus and / or process described herein, features of the invention, and advantages, defined solely by the claims, will become apparent in the detailed description described herein and understood in conjunction with the accompanying drawings. [Brief explanation of the drawing]

[0016] [Figure 1] Figure 1 is a diagram of a wound healing system according to an exemplary embodiment. [Figure 2] Figure 2 is an exploded perspective view of a portion of the wound treatment system shown in Figure 1, according to an exemplary embodiment. [Figure 3] Figure 3 is an exploded view of a canister of a wound healing system according to an exemplary embodiment. [Figure 4] Figure 4 is a cutaway side view of a portion of a wound healing system according to an exemplary embodiment. [Figure 5] Figure 5 is a cutaway perspective view of a wound healing system according to an exemplary embodiment. [Figure 6] Figure 6 shows the airflow path through the canister of a wound healing system according to an exemplary embodiment. [Figure 7] Figure 7 shows a combination of graphs representing the airflow through the airflow path of the canister in a wound healing system, according to an exemplary embodiment. [Figure 8] Figure 8 shows a combination of graphical representations of airflow through the airflow path of another canister in a wound healing system, according to an exemplary embodiment. [Figure 9] Figure 9 shows a combination of graphical representations of the airflow through yet another canister airflow path of the wound healing system according to an exemplary embodiment. [Figure 10] Figure 10 is a graph comparing evaporation in canisters corresponding to Figures 7-9, based on exemplary experiments and exemplary embodiments. [Modes for carrying out the invention]

[0017] Referring now to FIG. 1, a wound treatment system 100 according to an exemplary embodiment is shown. The wound treatment system 100 is configured to draw negative pressure at the wound, collect fluid or wound exudate from the wound in a canister, and facilitate evaporation of the fluid from the canister to the atmosphere. The wound treatment system 100 may be similar to or incorporate any of the features of the systems of U.S. Patent No. 8,821,458, filed Apr. 12, 2011; U.S. Patent No. 8,604,265, filed Apr. 12, 2011; U.S. Patent No. 9,023,002, filed Apr. 9, 2012; or U.S. Patent No. 9,433,711, filed Nov. 12, 2012, the entire disclosures of which are incorporated herein by reference.

[0018] The wound treatment system 100 includes a dressing 102, a canister (container, tank, vessel, etc.) 104 configured to be connected to the dressing 102 via a tube 106, and a treatment device 110 configured to be coupled to the canister 104. The treatment device 110 is shown as including a pump 112, a fan 114, a controller 116, and a power supply 118.

[0019] The dressing 102 is configured to seal over, for example, a patient's wound against the patient's anatomical structure, creating a substantially airtight seal between the patient's anatomical structure and the dressing 102. The dressing 102 includes an airtight outer drape layer that provides the seal and a manifold layer (e.g., a continuous bubble foam) between the outer layer and the patient, the manifold layer being configured to transmit air pressure to the patient (e.g., the wound) and to allow fluid (e.g., wound exudate) to flow out of the wound. The dressing may be the same as or similar to a PREVENA™ dressing with KCl and / or a V.A.C.® GRANUFOAM™ dressing with KCl in various embodiments.

[0020] Tube 106 is configured to connect dressing 102 to canister 104 and treatment device 110. Tube 106 can include a plurality of lumens. Tube 106 is configured to provide air flow and wound exudate flow from the dressing outward and to canister 104 when treatment device 110 is operated.

[0021] Treatment device 110 is shown as including a negative pressure source (shown as pump 112), fan 114, controller 116, and power supply 118. Pump 112 can be in fluid communication with tube 106 (e.g., via canister 104) to operate pump 112 to create a pressure differential that draws air, wound exudate, and / or other fluids or contaminants from dressing 102 through tube 106 toward canister 104. When air is removed from dressing 102, a negative pressure is established (with respect to atmospheric pressure) at dressing 102 and at the wound or other anatomical feature covered by dressing 102. Wound treatment system 100 can thereby promote wound healing by applying a negative pressure to the wound.

[0022] Wound exudate (e.g., blood, tissue, excrement, other contaminants) can be discharged from the wound by the negative pressure and the pressure differential created by pump 112. In particular, by operation of pump 112, wound exudate can be drawn into canister 104 through tube 106. Wound exudate can include a fluid containing water with various particles, contaminants, etc. therein. Removing wound exudate from the wound and dressing 102 can promote wound healing, for example, by reducing the risk of maceration of the area surrounding the wound, and can extend the duration that dressing 102 can be secured to the patient.

[0023] The canister 104 is configured to receive and hold wound exudate drawn from the dressing 102 via the tube 102. In embodiments herein, the canister 104 is configured to hold wound exudate while also allowing evaporation of water molecules from the canister 104 to the surrounding environment (e.g., the atmosphere), as will be described in detail below.

[0024] In Figure 1, the canister 104 is shown to include a first chamber 120 and a second chamber 122, configured to hold wound exudate received through the tube 102. The first chamber 120 and the second chamber 122 are at least partially separated by an airflow path 124. As shown in Figure 1, the airflow path 124 extends from an inlet 126 to an outlet 128. When the canister 104 is coupled to the treatment device 110, the inlet 126 is aligned with the fan 114.

[0025] The airflow path 124 is at least partially defined by the first wall 130 of the first chamber 120 and the second wall 132 of the second chamber 122. As will be described in detail below, the first wall 130 and the second wall 132 are formed as membranes (films, filters, etc.) that allow water molecules to pass through and evaporate into the airflow path 124, while preventing contaminants (e.g., particles, debris, cellular material, pathogens, oil, and other non-aqueous elements) held by the canister 104 from passing through the first wall 130 and the second wall 132. Thus, the airflow path 124 is configured to receive water molecules that evaporate into the airflow path 124 as air flows through it.

[0026] The fan 114 can be aligned with the airflow path 124 and operated to force air through the airflow path 124 (e.g., push, blow, etc.). In the embodiment shown in Figure 1, the fan 114 is configured to draw air from the ambient air and push it into the airflow path 124 through the inlet 126, thereby forcing air to flow from the inlet 126, which is close to the fan, to the outlet 128, which is at the opposite end of the first wall 130 and the second wall 132. In other embodiments, the fan 114 draws air through the airflow path 124 in the opposite direction. The fan 114 may be an axial flow fan driven by an electric motor. In other embodiments, other types of air movers (e.g., blowers, centrifugal fans) are used.

[0027] By blowing air through the airflow path 124 and along the first wall 130 and the second wall 132, the fan 114 actively increases the amount of water evaporating from the first chamber 120 and the second chamber 122 into the airflow path 124. The evaporation rate may be influenced by the velocity of the airflow through the airflow path 124, as well as other characteristics of the airflow (e.g., turbulence, pressure). These factors also affect the energy consumption and efficiency of the fan 114. Therefore, as will be described in detail below, the airflow path can be designed to increase the evaporation rate of water from the canister 104 while also reducing the energy consumption of the fan 114.

[0028] The fan 114 is configured to draw power from the power supply 118. The power supply 118 may be a battery, such as a rechargeable battery, that is mounted on the therapeutic device 110 (for example, in a housing 125 that also holds the pump 112 and the fan 114). By reducing the energy consumption of the fan 114, the battery life of the therapeutic device 110 (i.e., the amount of time the therapeutic device 110 can operate without being recharged) can be advantageously increased. In other embodiments, the power supply 118 is provided within the therapeutic device 110 as a circuit configured to draw power from an electrical outlet via a power cord. The power supply 118 is also configured to supply power to the pump 112 in the example in Figure 1.

[0029] In the example shown in Figure 1, the controller 116 is configured to control the fan 114 and the pump 112. The controller 116 can control the pump 112 to establish and maintain negative pressure in the dressing 102. The controller 116 can control the fan 114 to operate in a way that forces air through the airflow path 124 to promote evaporation. The controller can provide the fan 114 with an operating pattern that seeks to find an optimal balance between the energy consumption of the fan 114 and the evaporation of fluid from the canister 104. For example, the controller may circulate the fan 114 between an on state and an off state to reduce the power consumption of the fan 114. As another example, the controller may vary the fan speed of the fan 114 (for example, by varying the voltage supplied to the fan) to create variations in airflow that can help reduce power consumption (compared to constant operation at full speed) and increase the evaporation rate.

[0030] Figure 1 shows that the wound treatment system 100 is configured to establish and maintain negative pressure in the dressing 102 to provide negative pressure treatment to the wound, collect wound exudate in the canister 104, and actively promote the evaporation of water from the wound exudate in the canister 104. Due to this evaporation of water from the canister 104, the canister 104 remains below its maximum capacity for significantly longer than in embodiments where evaporation is not promoted. The feature that improves the evaporation rate increases the amount of time the wound treatment system 100 can be used without having to empty or replace the canister 104. In some cases, the wound treatment system 100 is configured to provide a sufficient amount of evaporation to prevent the canister 104 from reaching its capacity during a typical duration for treating a wound using the wound treatment system 100. Various features that provide promoted, energy-efficient evaporation of water from the canister 104, and features that facilitate the manufacture of the canister 104, are described in detail below with reference to Figures 2 to 10.

[0031] Referring now to Figure 2, an exploded perspective view of the canister 104 and the treatment device 110 according to an exemplary embodiment is shown. In particular, the treatment device 110 is shown in the exploded view so that the location of the fan 114 inside the treatment device 110 can be seen. As shown in Figure 2, the fan 114 is positioned between the first shell 202 and the second shell 204, which together form the housing of the treatment device 110.

[0032] The fan 114 is positioned to align with the inlet 126 of the airflow path of the canister 104. In the illustrated example, the fan 114 is an axial fan with an axis oriented perpendicular to the longitudinal axis of the canister 104, so that the surface of the fan is parallel to the wall of the second shell 204 of the housing of the treatment device 110 that covers the inlet 126 and can be fitted with it. Thus, the fan 114 is positioned to blow air in a direction perpendicular to the longitudinal axis.

[0033] Figure 2 also shows that the outlet 128 of the airflow path 124 is longitudinally spaced away from the inlet 126. As a result, the airflow path 124 extends in a direction at least partially offset from the axis of the fan 114. Thus, the airflow from the fan 114 through the canister 104 changes direction at least once between the inlet 126 and the outlet 128. This change of direction can create back pressure, turbulence, airflow velocity, etc., which can affect the fan's energy consumption and the evaporation rate into the airflow path 1204. Therefore, the improved design of the airflow path between the fan 114 and the outlet 128 can provide advantages for accelerated evaporation and more efficient fan operation, as will be described in detail below.

[0034] Figure 2 also shows that the therapeutic device 110 may include a user input panel 200 positioned on the outer surface of the first shell 202 of the housing of the therapeutic device 110. The user input panel 200 may include one or more buttons that allow the user to input requests to change the operation of the therapeutic device 110. For example, the user input panel 200 may be configured to provide a signal to the controller 116 indicating a user request to turn the fan 114 and / or pump 112 on or off. In some embodiments, the user input panel 200 allows the user to select an operating mode for the fan 114, such as a power level, fan speed, control routine from a plurality of selectable control routines, maximum evaporation mode, energy efficiency mode, etc. In such embodiments, the controller 116 is configured to control the fan 114 to provide the user-requested operation of the fan 114.

[0035] Referring now to Figure 3, an exploded view of a canister 104 according to an exemplary embodiment is shown. The canister 104 is shown to include a first wall (first membrane) 130 and a second wall (second membrane) 132 positioned between a first rigid support component 300 and a second rigid support component 302. The canister 104 is also shown to include a first outer shell 304 positioned on the opposite side of the second outer shell 306 such that the first rigid support component 300 and the second rigid support component 302 are positioned between the first outer shell 304 and the second outer shell 306. The first outer shell 304, the first rigid support component 300, and the first membrane 130 are assembled to define the first chamber 120 of the canister 104, and the second outer shell 306, the second rigid support component 302, and the second membrane 132 are assembled to form the second chamber 122 of the canister 104.

[0036] The first rigid support component 300 is configured to provide a substantially rigid support structure for supporting the first membrane 130. The first membrane 130 may be made from a relatively thin flexible material. As shown in Figure 3, the first rigid support component 300 includes an adjacent open hexagonal honeycomb structure configured to bond to the first membrane 130 in order to provide structural support to the first membrane 130 while exposing a large proportion of the surface area of ​​the first membrane 130 to the interior of the first chamber 120. The first rigid support component 300 also includes other surfaces, edges, etc., to provide the internal structure of the canister 104 and to bond the first rigid support component 300 and the first membrane 130 to other elements of the canister 104.

[0037] The second rigid support component 302 is configured to provide a substantially rigid support structure for supporting the second membrane 132. The second membrane 132 may be made from a relatively thin flexible material. As shown in Figure 3, the second rigid support component 302 includes an adjacent open hexagonal honeycomb structure configured to bond to the second membrane 132 in order to provide structural support to the second membrane 132 while exposing a large proportion of the second membrane 132's surface area to the interior of the second chamber 122. The second rigid support component 302 also includes other surfaces, edges, etc., to provide the internal structure of the canister 104 and to bond the second rigid support component 302 and the first membrane 130 to other elements of the canister 104.

[0038] The first outer shell 304 is configured to define the exposed outer surface of the canister 104, and the second outer shell 306 is configured to define the outer surface of the canister 104 that mates with the housing 125 of the therapeutic device 110. The second outer shell 306 includes an inlet 126 provided for alignment with the fan 114. The second rigid support component 302 includes a substantially cylindrical portion 308 of the airflow path 124. The cylindrical portion 308 extends across (through) the second rigid support component 302 from the inlet 126 of the second outer shell 306 to the space between the first membrane 130 and the second membrane 132. As shown in detail in Figure 6, the space between the first membrane 130 and the second membrane 132 defines a substantially planar portion 600 of the airflow path 124.

[0039] In some embodiments, the first outer shell 304, the first rigid support component 300, the first membrane 130, the second membrane 132, the second rigid support component 302, and the second outer shell 306 are ultrasonically welded together to form the canister 104. In particular, in the example shown in Figure 1, the first membrane 130 is ultrasonically welded directly to the first rigid support component 300, and the first rigid support component 300 is ultrasonically welded directly to the first outer shell 304 and the second rigid support component 302. The second membrane 132 is ultrasonically welded directly to the second rigid support component 302. The second rigid support component 302 is ultrasonically welded directly to the second outer shell 306.

[0040] To facilitate ultrasonic welding of the components of the canister 104, interchangeable materials are selected. For example, the first membrane 130 and the second membrane 132 may be made from a polyether urethane film, and the structural components (first outer shell 304, first rigid support component 300, second rigid support component 302, and second outer shell 306) may be made from a thermoplastic polyurethane resin, such as polyester-based thermoplastic polyurethane. The thermoplastic polyurethane resin has a substantially rigid structure, and the polyether urethane film has the evaporation and moisture transport properties described below. The materials are interchangeable so that ultrasonic welding of the materials can be achieved efficiently and reliably.

[0041] The first film 130 and the second film 132, formed from polyether urethane film, have a high water vapor transmission rate (MVTR) of approximately 2000 g / m² when measured, for example, in an upright cup test at 38°C and 90% relative humidity. 2 / day ~ approx. 5000g / m 2 MVTR within the range of / day (for example, approximately 4500g / m³) 2 The polyether urethane film may have a thickness of approximately 15 μm to approximately 100 μm, for example, approximately 20 μm to approximately 30 μm.

[0042] Referring now to Figures 4 and 5, cutaway diagrams of the canister 104 and treatment device 110 according to exemplary embodiments are shown. As shown in Figures 4 and 5, wound exudate is held in the canister 104, and the fan 114 is operated to force air through the canister 104 to reduce the volume of wound exudate stored in the canister 104, thereby actively promoting the evaporation of water molecules from the wound exudate.

[0043] Figure 4 shows the point at which canister 104 is nearly full, i.e., the amount of wound exudate in canister 104 is close to the maximum capacity of canister 104. Fan 114 is operated to force air through airflow path 124 to promote the evaporation of water molecules from the wound exudate held in canister 104 into airflow path 124. Water molecules permeate across the first membrane 130 and the second membrane 132 and are blown out as water vapor from outlet 128. Over time, the amount of water stored in canister 104 decreases significantly.

[0044] Figure 5 shows the point in time after fan 114 has been operated for a duration sufficient to provide a considerable amount of water evaporation from the canister to the surrounding environment. Compared to Figure 4, the level of wound exudate in Figure 5 is much lower (e.g., not close to the maximum capacity of canister 104). By facilitating evaporation provided by the teachings herein, it may be possible to reduce and / or maintain the amount of wound exudate to low levels, as shown in Figure 5. In various applications and situations (different wounds, different compositions of wound exudate, different ambient conditions, etc.), the rate of evaporation and the rate of accumulation or reduction of the wound exudate volume in canister 104 will vary.

[0045] Referring here to Figure 6, a diagram of the airflow path 124 in the example of Figures 2 to 5, according to an exemplary embodiment, is shown. Figure 6 includes a cutaway view of the canister 104 consistent with the above description. Figure 6 also includes a perspective view of the airflow path 124 separated from the depiction of the canister 104. Based on the physical structure of the canister 104, the airflow path comprises a planar portion 600 and a cylindrical portion 308 extending from the planar portion 600. The planar portion 600 is defined as the space between the first membrane 130 and the second membrane 132. The cylindrical portion 308 extends from the planar portion 600 to the inlet 126. Thus, a fan 114 adjacent to the inlet 126 can blow air directly along the cylindrical portion 308 until the air reaches the planar portion 600, and then the air is redirected along the planar portion to the outlet 128.

[0046] In the example of Figure 6, the cylindrical portion 308 of the airflow path 124 is perpendicular to the planar portion 600. Changes in the direction of airflow at the intersection between the cylindrical portion 308 and the planar portion 600 can create back pressure and turbulence, which can restrict airflow, as will be explained with reference to Figure 7 below. To improve the airflow between the cylindrical portion 308 and the planar portion 600 (for example, to reduce back pressure, to reduce turbulence, to increase airflow per unit of fan energy consumption), the airflow path 124 can be modified as shown in Figures 8 and 9 below. In various embodiments, as will be explained below, a curved surface is provided between the cylindrical portion 308 and the planar portion 600 to widen the cylindrical portion 308 closer to the planar portion 600, and the transition between them is smoothed by eliminating or reducing the acute angle between the wall of the cylindrical portion 308 and the planar portion 600. This may result in the cylindrical portion 308 still being approximately perpendicular to the planar portion 600 (as shown in Figure 8, which will be explained below). In other embodiments, the cylindrical portion 308 is rotated relative to the planar portion 600 such that an obtuse angle (in the range of 90° to 180°) is formed between the planar portion 600 and the cylindrical portion 308, thereby reducing the change in the direction of the airflow that occurs at the intersection between the cylindrical portion 308 and the planar portion 600 (as shown in Figure 9, which will be described below).

[0047] Referring here to Figures 7-9, illustrative graphs of experimental results from airflow experiments or simulations for different embodiments of the airflow path 124 are shown. Figure 7 shows the airflow path 124 in an embodiment consistent with the example in Figure 6, Figure 8 shows the airflow path 124 with an added curved surface to provide a smooth transition between the cylindrical portion 308 and the planar portion 600, and Figure 9 shows the cylindrical portion 308 rotated to open an obtuse angle between the cylindrical portion 308 and the planar portion 600. Figures 7-9 show half of the airflow path 124 for simplification, under the understanding that the behavior of the airflow path 124 and the airflow through it is substantially symmetrical. The exemplary experimental results shown in Figures 7-9 allow for comparison between these embodiments. The data shown are provided for illustrative purposes only and may vary for various embodiments of the treatment system 100 and various fan speeds, etc.

[0048] Figure 7 shows Table 700, a pressure diagram 702 showing the air pressure in the airflow path 124, an airflow velocity diagram 704 showing the velocity of the airflow passing through the airflow path 124, a turbulent side view 706 showing the turbulence in the airflow path 124 from a side view of the airflow path 124, and a turbulent perspective view 708 showing the turbulence in the airflow path 124 from a perspective view.

[0049] Table 700 shows the inlet pressure, mean surface velocity, mean outlet velocity, and outlet volumetric flow rate for the embodiment of the airflow path 124 shown in Figure 7. Pressure diagram 702 shows that high pressure is generated in the cylindrical section 308 by the operation of the fan 114 due to the restriction of airflow at the intersection between the planar section 600 and the cylindrical section 308. The pressure in the planar section 600 is substantially lower than that in the cylindrical section 308. Higher pressure in the cylindrical section 308 could increase the power load on the fan 114. Airflow velocity diagram 704 shows that, for similar reasons, a relatively low airflow velocity is provided to the cylindrical section 308, while an irregular airflow velocity is provided through the planar section 600. Turbulent side view 706 and turbulent perspective view 708 show the amount of turbulence in the airflow path 124. In particular, a large amount of turbulence corresponding to high air velocities is shown in the planar section 600.

[0050] Figure 8 shows the smooth transition between the cylindrical portion 308 and the planar portion 600, provided by a curved surface 850 located between the cylindrical portion 308 and the planar portion 600. Figure 8 also shows Table 800, a pressure diagram 802 of the air pressure in the airflow path 124, an airflow velocity diagram 804 showing the velocity of the airflow through the airflow path 124, a turbulent side view 806 showing the turbulence in the airflow path 124 from a side view of the airflow path 124, and a turbulent perspective diagram 808 showing the turbulence in the airflow path 124 from a perspective view.

[0051] Pressure diagram 802 shows that, compared to the pressure shown in pressure diagram 702 of Figure 7, the embodiment of Figure 8 provides a relatively uniform and relatively low pressure throughout the airflow path 124. This allows for lower power consumption of the fan 114. The pressure in the cylindrical section 308 may be slightly higher, but not significantly higher, than the pressure in the planar section 600. Airflow velocity diagram 804 shows an increased velocity at the curved surface 850, along with a relatively consistent and relatively low airflow velocity across the planar section 600. As shown in Table 800, the average outlet velocity of the embodiment of Figure 8 is substantially lower than the average outlet velocity of the embodiment of Figure 7. Turbulence diagrams 806 and 808 show turbulence that begins at the curved surface 850 and decreases as the air flows along the planar section 600.

[0052] Figure 9 shows a cylindrical portion 308 oriented at an obtuse angle (indicated as θ in Figure 9) with respect to a planar portion 600. The obtuse angle θ can be any angle between 90° and 180°, and preferably in the range of about 130° to about 150° (for example, about 135°). Figure 9 shows Table 900, a pressure diagram 902 of the air pressure in the airflow path 124, an airflow velocity diagram 904 showing the velocity of the airflow through the airflow path 124, a turbulent side view 906 showing the turbulence in the airflow path 124 from a side view of the airflow path 124, and a turbulent perspective view 908 showing the turbulence in the airflow path 124 from a perspective view.

[0053] Due to the angle of the cylindrical portion 308 relative to the planar portion 600, pressure diagram 902 shows that the air pressure in the cylindrical portion 308 is relatively low compared to the embodiment in Figure 7, and the increase in velocity at the intersection of the cylindrical portion 308 and the planar portion 600, as shown by airflow velocity diagram 904, is lower than in the embodiments in Figures 7 and 8. Turbulence diagrams 906 and 908 show that turbulence similar to that in the example in Figure 8 is generated in the planar portion 600 in the example in Figure 9. This turbulence may help to break down the surfaces of the first film 130 and the second film 132 to promote evaporation. The average outlet velocity and average surface velocity shown in Table 900 for the example in Figure 9 are slightly lower than those shown in Table 800 for the example in Figure 8.

[0054] Referring here to Figure 10, Table 1000 is shown comparing the amount of evaporation from the canister 104 provided by the exemplary embodiments of Figures 7 to 9 through exemplary experiments. As shown in Figure 10, the example of Figure 8 (i.e., an embodiment of the canister 104 in which a curved surface 850 is provided at the intersection of the cylindrical portion 308 and the planar portion 600) yields more evaporation than the example of Figure 7, while the example of Figure 9 (i.e., an embodiment in which the cylindrical portion 308 is obtuse with respect to the planar portion 600) yields more evaporation than the example of Figure 9. The experiment in Figure 10 may be performed using fan speed and / or power consumption as fixed values ​​across the three embodiments, so that the example of Figure 9 provides the most efficient evaporation for the power consumption of the fan 114. Figure 10 shows that any of the embodiments herein can actively promote the evaporation of water from the canister 104, thereby extending the life of the canister 104.

[0055] When used herein, the terms “approximately,” “about,” “substantially,” and similar terms are intended to have a broad meaning consistent with the common and accepted usage by those skilled in the art in which the subject matter of this disclosure pertains. Those skilled in the art reviewing this disclosure will understand that these terms are intended to enable the description of certain features described and claimed without limiting the scope of those features to the exact numerical range provided. Accordingly, these terms should be interpreted as indicating that a non-substantial or insignificant modification or alteration of the subject matter described and claimed is considered to fall within the scope of this disclosure as set forth in the appended claims.

[0056] When used herein to describe various embodiments, the terms “exemplary” and their variations are intended to indicate that such embodiments are possible examples, representations, or illustrations of possible embodiments (and such terms are not intended to imply that such embodiments are necessarily special or best examples).

[0057] As used herein, the term “joined” means connecting two members directly or indirectly to one another. Such connections may be stationary (e.g., permanent or fixed) or movable (e.g., detachable or releaseable). Such connections may be achieved by the two members being directly joined to one another, by the two members being joined to one another using separate intervening members and any additional intermediate members joined to one another, or by the two members being joined to one another using an intervening member integrally formed with one of the two members as a single aggregate body. Such members may be joined mechanically, electrically, and / or fluidly.

[0058] References to the position of elements in this specification (e.g., “top,” “bottom,” “up,” “down,” etc.) are used simply to describe the orientation of various elements in the figures. Note that the orientation of various elements may differ according to other exemplary embodiments, and such variations are intended to be included in this disclosure.

Claims

1. A canister for use with a wound healing system, A first compartment and a second compartment configured to receive and contain wound exudate, An airflow path, A planar region positioned between the first section and the second section, An entrance extending from the first end of the planar region at an obtuse angle to the planar region, An airflow path comprising an outlet at the second end of the planar region, A canister equipped with this feature.

2. The first section is, This allows water molecules to pass from the first compartment to the airflow path. To prevent contaminants from passing from the first compartment into the airflow path. The canister according to claim 1, separated from the airflow path by a first filter configured as such.

3. The canister according to claim 2, wherein the first filter includes a polyether urethane film.

4. The canister according to claim 3, comprising a rigid structure formed of thermoplastic polyurethane resin that defines the first and second sections.

5. The rigid structure is ultrasonically welded to the polyether urethane film, as described in claim 4.

6. The canister according to claim 2, wherein the first filter includes a film having high water vapor permeability.

7. The aforementioned high water vapor permeability is 2000 to 5000 g / m³ ２ The canister according to claim 6, which is within the range of / day.

8. The canister according to claim 1, wherein the inlet is cylindrical.

9. The canister according to claim 1, wherein the inlet is formed to match the cross-sectional shape of the fan.

10. The canister according to claim 1, wherein the inlet widens in close proximity to the planar region in order to reduce turbulence and back pressure in the airflow path.

11. The canister according to claim 1, further comprising a curved wall that provides a smooth transition from the entrance to the planar area.

12. The canister according to claim 1, wherein the obtuse angle is in the range of 130° to 150°.

13. The canister according to claim 1, wherein the inlet has a screw-type configuration configured to provide rotation of the airflow passing through it.

14. It is a treatment system, A dressing configured to cover and seal the wound site, A negative pressure source configured to draw in negative pressure in the dressing so that wound exudate can escape from the dressing, A canister configured to be arranged in fluid communication with the dressing, A first compartment and a second compartment configured to receive and retain the wound exudate from the dressing, An airflow path, A planar region positioned between the first section and the second section, An entrance extending from the first end of the planar region at an obtuse angle to the planar region, An airflow path comprising an outlet at the second end of the planar region, Equipped with a canister, An air mover, aligned with the aforementioned inlet and configured to forcibly pass air through the airflow path in order to facilitate the transport of moisture from the wound exudate coming out of the first and second compartments, A treatment system that includes this.

15. The treatment system according to claim 14, wherein the air mover is an axial flow fan.

16. The treatment system according to claim 14, wherein the air mover is a blower.

17. The treatment system according to claim 14, wherein the air mover is a centrifugal fan.

18. The treatment system according to claim 14, comprising a housing, wherein the air mover and the negative pressure source are installed within the housing, and the canister is configured to be selectively and detachably coupled to the housing.

19. The treatment system according to claim 18, further comprising a battery installed in the housing and configured to supply power to the air mover and the negative pressure source.

20. The treatment system according to claim 14, further comprising a controller configured to control the air mover to operate in a pulsing pattern.

21. The treatment system according to claim 14, further comprising a tube for connecting the dressing to the canister.

22. The first section and the second section are, This allows water molecules to pass from the first and second compartments to the airflow path. To prevent contaminants from passing from the first and second compartments into the airflow path. The treatment system according to claim 14, wherein the airflow path is separated by a film material configured in such a manner.

23. A method for manufacturing a canister for a wound healing device, To provide a first rigid structure and a second rigid structure made of polyurethane resin, To provide a first filter and a second filter formed from a polyether urethane film, The first rigid structure is ultrasonically welded to the first filter, The second rigid structure is ultrasonically welded to the second filter, The first rigid structure is ultrasonically welded to the second rigid structure such that a planar airflow path is defined between the first filter and the second filter. A method that includes this.

24. The method according to claim 23, further comprising coupling the first wall to the first rigid structure such that the first section is defined by the first wall, the first rigid structure, and the first filter.

25. The method according to claim 24, further comprising coupling the second wall to the second rigid structure such that the second section is defined by the second wall, the second rigid structure, and the second filter.

26. The method according to claim 23, further comprising configuring the second rigid structure such that it defines an inlet extending across the second rigid structure from the planar airflow path.

27. The method according to claim 23, comprising forming the first filter and the second filter such that the first filter and the second filter are configured to allow water molecules to pass across the first filter and the second filter.

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