HEAT EXCHANGER WITH THERMAL STRESS-RELIEF AREAS

Information

  • Patent Application
  • 20210381778
  • Publication Number
    20210381778
  • Date Filed
    March 31, 2021
    3 years ago
  • Date Published
    December 09, 2021
    3 years ago
Abstract
A heat exchanger with a front group of heat exchange conduits extending between a front inlet tank and a front outlet tank. A rear group of heat exchange conduits extend between a rear inlet tank and a rear outlet tank. A reinforcing plate is adjacent to the front group of heat exchange conduits and the rear group of heat exchange conduits to restrict twisting thereof. A first stress-relief area of the reinforcing plate is proximate to, and spaced apart from, both the front inlet tank and the rear inlet tank. A second stress-relief area of the reinforcing plate is proximate to, and spaced apart from, both the front outlet tank and the rear outlet tank.
Description
FIELD

The present disclosure relates to a heat exchanger including a reinforcing plate with stress-relief areas.


BACKGROUND

This section provides background information related to the present disclosure, which is not necessarily prior art.


Vehicles often include heat exchangers for cooling and/or heating various vehicle components. While current heat exchangers are suitable for their intended use, they are subject to improvement. For example, heat exchangers with multiple rows of heat exchange tubes may experience temperature fluctuations amongst the tubes, thereby causing the tubes to undergo uneven thermal expansion and contraction. This uneven expansion and contraction subjects the tubes to increased strain. The present disclosure advantageously includes heat exchangers with increased durability that can reduce tube strain and increase the lifespan of the heat exchanger.


SUMMARY

This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.


The present disclosure includes a heat exchanger with a front group of heat exchange conduits extending between a front inlet tank and a front outlet tank. A rear group of heat exchange conduits extend between a rear inlet tank and a rear outlet tank. A reinforcing plate is adjacent to the front group of heat exchange conduits and the rear group of heat exchange conduits to restrict twisting thereof. A first stress-relief area of the reinforcing plate is proximate to, and spaced apart from, both the front inlet tank and the rear inlet tank. A second stress-relief area of the reinforcing plate is proximate to, and spaced apart from, both the front outlet tank and the rear outlet tank.


The present disclosure also includes a heat exchanger having a front group of heat exchange conduits extending between a front inlet tank and a front outlet tank. A rear group of heat exchange conduits extend between a rear inlet tank and a rear outlet tank. A top reinforcing plate is at a top of both the front group of heat exchange conduits and the rear group of heat exchange conduits. A first top stress-relief opening is defined by the top reinforcing plate proximate to, and spaced apart from, both the front inlet tank and the rear inlet tank. A second top stress-relief opening is defined by the top reinforcing plate proximate to, and spaced apart from, both the front outlet tank and the rear outlet tank. A bottom reinforcing plate is at a bottom of both the front group of heat exchange conduits and the rear group of heat exchange conduits. A first bottom stress-relief opening is defined by the bottom reinforcing plate proximate to, and spaced apart from, both the front inlet tank and the rear inlet tank. A second bottom stress-relief opening is defined by the bottom reinforcing plate proximate to, and spaced apart from, both the front outlet tank and the rear outlet tank. The first top stress-relief opening, the second top stress-relief opening, the first bottom stress-relief opening, and the second bottom stress-relief opening are configured to promote twisting of portions of the front group of heat exchange conduits and the rear group of heat exchange conduits at areas spaced apart from the first inlet tank, the second inlet tank, the first outlet tank, and the second outlet tank.


Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.





DRAWINGS

The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.



FIG. 1 illustrates a heat exchanger in accordance with the present disclosure;



FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1;



FIG. 3 is a top view of a reinforcing plate of the heat exchanger of FIG. 1;



FIG. 4 illustrates area 4 of FIG. 3;



FIG. 5 is a perspective view of the reinforcing plate;



FIG. 6 is a perspective view of another reinforcing plate for the heat exchanger of FIG. 1 in accordance with the present disclosure; and



FIG. 7 is a graph illustrating exemplary tube twist angle of the heat exchanger of FIG. 1 as compared to an existing heat exchanger.





Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.


DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference to the accompanying drawings.



FIGS. 1 and 2 illustrate an exemplary heat exchanger 10 in accordance with the present disclosure. The heat exchanger 10 may be configured for use in any suitable application to transfer heat to or from any suitable working fluid flowing through the heat exchanger 10. Suitable working fluids include, but are not limited to, refrigerant, coolant, oil, water, etc. The heat exchanger 10 may be configured for use in any suitable application, such as any suitable automotive application. Suitable automotive applications include, but are not limited to, fully electric vehicles, hybrid vehicles, plug-in hybrid vehicles, vehicles with internal combustion engines, etc. The heat exchanger 10 may be configured for cooling/heating any suitable vehicle components, such as an inverter, an electric motor, an onboard vehicle charger, a battery, a turbocharger, a DC-DC converter, an internal combustion engine, etc.


The heat exchanger 10 includes a front inlet tank 12 with a front inlet 14, and a front outlet tank 16 with a front outlet 18. The heat exchanger 10 further includes a rear inlet tank 20 with a rear inlet 22, and a rear outlet tank 24 with a rear outlet 26. Extending between the front inlet tank 12 and the front outlet tank 16 is a first group of heat exchanger conduits 40. Extending between the rear inlet tank 20 and the rear outlet tank 24 is a rear group of heat exchanger conduits 42 (see FIG. 2). As illustrated in FIG. 2, the front group of heat exchanger conduits 40 includes a plurality of conduits 44 (such as tubes, for example) extending between, and in fluid communication with, the front inlet tank 12 and the front outlet tank 16. Similarly, the rear group of heat exchanger conduits 42 includes a plurality of conduits 46 (such as tubes, for example) extending between, and in fluid communication with, the rear inlet tank 20 and the rear outlet tank 24. The heat exchanger 10 is thus a multiple row heat exchanger. When included with an engine cooling system for a vehicle, the heat exchanger 10 is typically arranged with the front group of heat exchanger conduits 40 facing a front end of the vehicle, and with the rear group of heat exchanger conduits 42 facing a rear of the vehicle.


Working fluid enters the heat exchanger 10 through the front inlet 14 and the rear inlet 22, and flows into the front inlet tank 12 and the rear inlet tank 20 respectively. The working fluid entering the front inlet 14 may be the same as, or different from, the working fluid entering the rear inlet 22. From the front inlet tank 12, working fluid flows through the conduits 44 across the heat exchanger 10 to the front outlet tank 16. Working fluid exits the front outlet tank 16 through the front outlet 18. From the rear inlet tank 20, working fluid flows through the conduits 46 across the heat exchanger 10 to the rear outlet tank 24. Working fluid exits the rear outlet tank 24 through the rear outlet 26. As the working fluid flows through the conduits 44, 46, heat is transferred to or from the working fluid to heat or cool the working fluid depending on the application. In some applications, working fluid circulating through the front conduits 44 will be at a different temperature from working fluid circulating through the rear conduits 46, which will cause thermal stress on the conduits 44, 46. When the working fluid circulating through the front conduits 44 is used for cooling and the working fluid circulating through the rear conduits 46 is used for heating (or vice versa) the thermal stress on the conduits 44, 46 will be particularly high.


A top reinforcing plate 50A extends from the front inlet tank 12 and the rear inlet tank 20 to the front outlet tank 16 and the rear outlet tank 24. The top reinforcing plate 50A is at a top of the front group of heat exchanger conduits 40 and the rear group of heat exchanger conduits 42. A bottom reinforcing plate 50B extends from the front inlet tank 12 and the rear inlet tank 20 to the front outlet tank 16 and the rear outlet tank 24. The bottom reinforcing plate 50B is at a bottom of the front and rear groups of heat exchanger conduits 40, 42.


With continued reference to FIGS. 1 and 2, and additional reference to FIGS. 3-5, the top reinforcing plate 50A includes a base 52A. On opposite sides of the base 52A is a front flange 54A and a rear flange 56A, which extend along the length of the base 52A. A mid-line M of the base 52A is halfway between the front flange 54A and the rear flange 56A. As illustrated in the example of FIG. 5, the base 52A may further include a center flange 58A extending along the mid-line M. The center flange 58A extends parallel to the front and rear flanges 54A, 56A.


The top reinforcing plate 50A is attached to the tanks 12, 16, 20, 24 in any suitable manner. In the example illustrated, the top reinforcing plate 50A includes tabs 70 (see FIG. 5, for example), which are seated in slots defined by the tanks 12, 16, 20, 24. The bottom reinforcing plate 50B may include similar tabs seated in slots of each one of the tanks 12, 16, 20, 24. The top and bottom reinforcing plates 50A, 50B may be connected to the tanks 12, 16, 20, 24 in any other suitable manner as well to reduce twisting of the conduits 44, 46. The bottom reinforcing plate 50B is substantially similar to, or the same as the top reinforcing plate 50A, and thus the description of the top reinforcing plate 50A also serves to describe the bottom reinforcing plate 50B.


The top reinforcing plate 50A and the bottom reinforcing plate 50B include a plurality of stress relief areas to relieve stress of the roots of the conduits 40, 42, which is where the conduits 40, 42 connect to the tanks 12, 16, 20, 24. In the example illustrated in FIG. 1, the top reinforcing plate 50A includes a first stress relief area 16A, which is proximate to, and spaced apart from, both the front inlet tank 12 and the rear inlet tank 20. The top reinforcing plate 50A further includes a second stress relief area 16B, which is proximate to, and spaced apart from, both the front outlet tank 16 and the rear outlet tank 24. The bottom reinforcing plate 50B includes a third stress relief area 60C proximate to, and spaced apart from, both the front and rear inlet tanks 12, 20. A fourth stress relief area of the bottom reinforcing plate 50B is proximate to, and spaced apart from, the front and rear outlet tanks 16, 24.


With continued reference to FIGS. 1 and 2, and additional reference to FIGS. 3-5, the first stress relief area 60A will now be described in further detail. The stress relief areas 60A, 60B, 60C, and 60D may have the same or similar configuration. The following description of the first stress relief area 60A thus also applies to each one of the second stress relief area 60B, the third stress relief area 60C, and the fourth stress relief area 60D.


The first stress relief area 60A includes a base opening 62A defined by the base 52A. The base opening 62A extends across the mid-line M and is generally hourglass-shaped. The base opening 62A has a tapered area 64A at the mid-line M. The mid-line M is generally a line of symmetry of the base opening 62A. The first stress relief area 60A further includes one or more side openings 66A at the front and rear flanges 54A, 56A. The side openings 66A extend from the flanges 54A, 56A to the base 52A. Any suitable number of side openings 66A may be included, and the side openings 66A may be arranged at any suitable position relative to the base opening 62A. In the example illustrated, four side openings 66A are included. The base opening 62A is between two of the side openings 66A at the front flange 54A, and two of the side openings 66A at the rear flange 56A.


The base opening 62A may alternatively have any other suitable shape for relieving stress. For example and as illustrated in FIG. 6, the hourglass shape may be replaced with two T-shaped openings 80A and 80A′. The two T-shaped openings 80A, 80A′ are on opposite sides of the mid-line M and the center flange 58A. Each T-shaped opening 80A, 80A′ includes a first portion 82A, 82A′ and a second portion 84A, 84A′. The first portions 82A, 82A′ are proximate to the front and rear flanges 54A, 56A respectively, and extend generally parallel to the flanges 54A, 56A and the mid-line M. Each of the T-shaped openings 80A, 80A′ also include a second portion 84A, 84A′, which is closer to the mid-line M than the first portions 82A, 82A′. The second portions 84A, 84A′ are each generally at a mid-point of the lengths of the first portions 82A, 82A′ respectively. The first and second T-shaped openings 80A, 80A′ are on opposite sides of the center flange 58A.


The openings 62A, 66A, 80A, 80A′ may be formed in any suitable manner, such as with any suitable cutting or stamping technique, for example. Alternatively, the top and bottom reinforcing plates 50A, 50B may be formed by any suitable three-dimensional printing process, and the openings 62A, 66A, 80A, 80A′ may be formed in (and defined by) the top and bottom reinforcing plates 50A, 50B during the three-dimensional printing process. In some applications, the reinforcing plates 50A, 50B may be formed by injection molding, and the openings 62A, 66A, 84A, 84A′ may be defined by the mold.


As another alternative contemplated by the present teachings, the stress relief areas 60A-60D may be weakened areas of the reinforcing plates 50A, 50B, not openings defined in the reinforcing plates 50A, 50B. Thus at each of the stress relief areas 60A-60D, the reinforcing plates 50A, 50B may be made of a material that is relatively less rigid or strong as compared to the rest of the plates 50A, 50B. For example, when the plates 50A, 50B are formed by three-dimensional printing, the material used to form the stress relief areas 60A-60D may be less rigid than (and thus relatively weaker than) the material used to form the rest of the reinforcing plates 50A, 50B.


The stress relief areas 60A-60D provide numerous advantages. For example, because the heat exchanger 10 is a multiple row heat exchanger including the front group of heat exchanger conduits 40 and the rear group of heat exchanger conduits 42, the plurality of conduits (e.g., tubes) 44, 46 may have discrete working fluid flows at various different temperatures, which may cause uneven thermal expansion and contraction throughout the conduits 44, 46. The occurrence of uneven thermal expansion and contraction is particularly great in applications in which the working fluid circulating through the front conduits 44 is used for cooling the working fluid circulating through the rear conduits 46 is used for heating, or vice versa. This uneven expansion and contraction results in twisting of the conduits 44, 46, which places strain thereon. Heat exchangers that do not include the stress relief areas 60A-60B experience this twisting of the conduits 44, 46 typically at the interface between the conduits 44 and the tanks 12, 16, and at the interface between the conduits 42 and the tanks 20, 24.


The stress relief areas 60A-60D generally prevent local twisting of the conduits 44, 46 at the interfaces with the tanks 12, 16, 20, 24. The stress relief areas 60A-60D promote twisting of the front and rear groups of heat exchanger conduits 40, 42 at areas of the conduits 44, 46 aligned with the stress relief areas 60A-60D. Thus instead of the conduits 44, 46 being subject to the stress and strain at the interfaces with the tanks 12, 16, 20, 24, the stress relief areas 60A-60D promote twisting of the conduits 44, 46 between the first and third stress relief area 60A, 60C, and between the second and the fourth stress relief areas 60B, 60D. By shifting the stress on the conduits 44, 46 away from the roots at the tanks 12, 16, 20, 24, strain on the conduits 44, 46 can be reduced by up to 15% compared to heat exchangers that do not include the stress relief areas 60A-60D. The stress relief areas 60A-60D advantageously increase the durability of the heat exchanger 10 without compromising performance thereof.



FIG. 7 is a chart graphically illustrating advantages of the stress relief areas 60A-60D as compared to an exemplary baseline reinforcing plate without the stress relief areas 60A-60D. As shown in FIG. 7, at the roots of the conduits or tubes 44, 46 where they mate with the tanks 12, 16, 20, 24, the twist angle of the reinforcing plates 50A, 50B is less than the twist angle of the reinforcing plate without the stress relief areas 60A-60D. Area A of FIG. 7 illustrates the influence of an exemplary one of the stress relief areas 60A-60D. At area A spaced apart from the roots, the tubes 44, 46 between stress relief areas 60A, 60C or 60B, 60D experience an increase in twist angle due to the presence of the stress relief areas 60A-60D, which relieves stress at the roots of the tubes and protects the roots from potential damage. Thus the stress relief areas 60A-60D promote twisting of the tubes 44, 46 between the stress relief areas 60A, 60C and 60B, 60D, which relieves stress at the roots of the tubes 44, 46. One skilled in the art will appreciate that the present disclosure provides numerous additional advantages and unexpected results as well.


The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.


Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.


The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.


When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.


Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.


Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Claims
  • 1. A heat exchanger comprising: a front group of heat exchange conduits extending between a front inlet tank and a front outlet tank;a rear group of heat exchange conduits extending between a rear inlet tank and a rear outlet tank;a reinforcing plate adjacent to the front group of heat exchange conduits and the rear group of heat exchange conduits to restrict twisting thereof;a first stress-relief area of the reinforcing plate proximate to, and spaced apart from, both the front inlet tank and the rear inlet tank; anda second stress-relief area of the reinforcing plate proximate to, and spaced apart from, both the front outlet tank and the rear outlet tank.
  • 2. The heat exchanger of claim 1, wherein the reinforcing plate extends from the front inlet tank to the front outlet tank, and from the rear inlet tank to the rear outlet tank.
  • 3. The heat exchanger of claim 1, wherein the first stress-relief area and the second stress-relief area are configured to promote twisting of portions of the front group of heat exchange conduits and the rear group of heat exchange conduits that are aligned with the first stress-relief area and the second stress-relief area.
  • 4. The heat exchanger of claim 1, wherein the first stress-relief area and the second stress-relief area of the reinforcing plate are less rigid than portions of the reinforcing plate adjacent thereto.
  • 5. The heat exchanger of claim 1, wherein the first stress-relief area and the second stress-relief area each include openings in the reinforcing plate.
  • 6. The heat exchanger of claim 1, wherein the first stress-relief area and the second stress-relief area each include openings in the reinforcing plate extending across a mid-line of the reinforcing plate.
  • 7. The heat exchanger of claim 1, wherein the first stress-relief area and the second stress-relief area each include openings in the reinforcing plate on opposite sides of a mid-line of the reinforcing plate.
  • 8. The heat exchanger of claim 1, wherein the first stress-relief area and the second stress-relief area each include openings in the reinforcing plate that are most narrow at a mid-line of the reinforcing plate.
  • 9. The heat exchanger of claim 1, wherein the first stress-relief area and the second stress-relief area each include hourglass-shaped openings.
  • 10. The heat exchanger of claim 1, wherein the first stress-relief area and the second stress-relief area each include t-shaped openings.
  • 11. The heat exchanger of claim 1, wherein the reinforcing plate includes side flanges extending along a length of the reinforcing plate; and wherein each of the first stress-relief area and the second stress-relief area include openings at the side flanges.
  • 12. The heat exchanger of claim 11, wherein each of the first stress-relief area and the second stress-relief area include at least one additional opening inboard of the side flanges.
  • 13. The heat exchanger of claim 11, wherein the reinforcing plate further includes a center flange between the side flanges at a mid-line of the reinforcing plate.
  • 14. The heat exchanger of claim 1, wherein the reinforcing plate is a top reinforcing plate at a top of both the front group of heat exchange conduits and the rear group of heat exchange conduits, the heat exchanger further including a bottom reinforcing plate at a bottom of both the front group of heat exchange conduits and the rear group of heat exchange conduits, the bottom reinforcing plate includes: a third stress-relief area defined by the bottom reinforcing plate proximate to, and spaced apart from, both the front inlet tank and the rear inlet tank; anda fourth stress-relief area defined by the bottom reinforcing plate proximate to, and spaced apart from, both the front outlet tank and the rear outlet tank.
  • 15. A heat exchanger comprising: a front group of heat exchange conduits extending between a front inlet tank and a front outlet tank;a rear group of heat exchange conduits extending between a rear inlet tank and a rear outlet tank;a top reinforcing plate at a top of both the front group of heat exchange conduits and the rear group of heat exchange conduits;a first top stress-relief opening defined by the top reinforcing plate proximate to, and spaced apart from, both the front inlet tank and the rear inlet tank;a second top stress-relief opening defined by the top reinforcing plate proximate to, and spaced apart from, both the front outlet tank and the rear outlet tank;a bottom reinforcing plate at a bottom of both the front group of heat exchange conduits and the rear group of heat exchange conduits;a first bottom stress-relief opening defined by the bottom reinforcing plate proximate to, and spaced apart from, both the front inlet tank and the rear inlet tank; anda second bottom stress-relief opening defined by the bottom reinforcing plate proximate to, and spaced apart from, both the front outlet tank and the rear outlet tank;wherein the first top stress-relief opening, the second top stress-relief opening, the first bottom stress-relief opening, and the second bottom stress-relief opening are configured to promote twisting of portions of the front group of heat exchange conduits and the rear group of heat exchange conduits at areas spaced apart from the front inlet tank, the rear inlet tank, the front outlet tank, and the rear outlet tank.
  • 16. The heat exchanger of claim 15, wherein the top reinforcing plate and the bottom reinforcing plate both extend from the front inlet tank to the front outlet tank, and from the rear inlet tank to the rear outlet tank.
  • 17. The heat exchanger of claim 15, wherein at least one of the first top stress-relief opening and the second top stress-relief opening extend across a mid-line of the top reinforcing plate.
  • 18. The heat exchanger of claim 15, wherein at least one of the first top stress-relief opening and the second top stress-relief opening is most narrow at a mid-line of the reinforcing plate.
  • 19. The heat exchanger of claim 15, wherein the top reinforcing plate and the bottom reinforcing plate each include side flanges with side openings proximate to the first top stress-relief opening, the second top stress-relief opening, the first bottom stress-relief opening, and the second bottom stress-relief opening.
  • 20. The heat exchanger of claim 19, wherein both the top reinforcing plate and the bottom reinforcing plate include a center flange between the side flanges.
CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No. 63/034,477 filed on Jun. 4, 2020, the entire disclosure of which is incorporated herein by reference.

Provisional Applications (1)
Number Date Country
63034477 Jun 2020 US