WO2020139461A2

WO2020139461A2 - Systems, apparatus, and methods useful for enhanced maintenance of stormwater management systems

Info

Publication number: WO2020139461A2
Application number: PCT/US2019/059283
Authority: WO
Inventors: Greg SPIRES; Brian Rustia; Evan GENO; Michael Kuehn
Original assignee: Advanced Drainage Systems, Inc.
Priority date: 2018-10-30
Filing date: 2019-10-31
Publication date: 2020-07-02
Also published as: WO2020139461A3; US20200263409A1; MX2021005062A; EP3870765A1; CL2021001129A1; WO2021086460A1; BR112021008645A2; WO2021086461A1; CA3118333A1; CL2021001130A1; AU2020373243A1; EP3870764A1; EP3870765A4; AU2020372743A1; BR112021010212A2; MX2021005061A; EP3870764A4; CA3134863A1

Abstract

An embodiment of apparatus useful for chamber-type stormwater management systems includes an inclined surface comprising a first end and a second end. The ramp is configured to connect to a chamber end cap having a stub pipe centrally disposed therethrough. The ramp is connected to the stub pipe at the second end of the ramp, a ramp surface inclined to form a slope rising from the first end to the second end.

Description

SYSTEMS, APPARATUS, AND METHODS USEFUL FOR ENHANCED MAINTENANCE

OF STORMWATER MANAGEMENT SYSTEMS

RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. provisional application 62/753,050, filed

October 30, 2018, titled SYSTEMS, APPARATUS, AND METHODS USEFUL FOR ENHANCED MAINTENANCE OF STORMWATER MANAGEMENT SYSTEMS, the entire disclosure of which is hereby incorporated by reference herein.

FIELD

[0002] The disclosure relates to systems, apparatus, and methods useful for fluid run-off management systems. In particular, the disclosure relates to enhancing efficiency and efficacy of fluid run-off system maintenance.

BACKGROUND

[0003] Fluid run-off systems include systems designed to process rainwater or other fluid run-off and particularly stormwater. Related art stormwater management systems include chamber systems including those available from Advanced Drainage Systems, Inc. under the STORMTECH® brand. Such systems are designed primarily for use under parking lots, roadways, and heavy earth loads. [0004] STORMTECH® chambers are thermoplastic, injection molded, and formed of polypropylene, polyethylene, or a combination thereof. Such a chamber has an elliptical arched cross-section, and is formed to have a long, narrow configuration with an advantageously compact footprint that optimizes use of space. The arch-shaped chamber defines an open bottom. The chamber is installed and placed on crushed stone or other porous medium, which constitutes a floor of the chamber underlying the arch. The chamber may be formed to include corrugations, which may be advantageously shaped and configured to accommodate efficient stormwater or fluid run-off management and debris collection. One or more of chambers includes an inlet configured to connect to a stormwater collection system, which may include one or more drain basins that receive fluid run-off from a parking lot, roof, or street. The chamber is designed to distribute collected stormwater into the ground. [0005] During a storm, stormwater or rainwater run-off enters the chamber from the one or more drain basins, and in some system configurations, may exit the chamber by flowing through a conduit connecting the chamber to another system component, such as a basin or another chamber. By way of example, a chamber-type stormwater management system may include an array of chambers buried in crushed stone. The chambers may be connected in parallel or in series.

[0006] Stormwater carries debris and solid contaminants that can pass into and through basins, traps, and filters of conventional stormwater management systems. Stormwater may include suspended solids, including dirt, sand, organic debris such as leaves, paper, and plastic. Stormwater management system chambers such as the STORMTECH® chambers are configured to receive stormwater and allow debris to settle to a bottom of the chamber before the stormwater is released into the ground.

[0007] Related art stormwater management systems have been developed that prevent some debris and solid contaminants from reaching the chambers. For example, some chamber- type stormwater management systems are configured to divert surface stormwater to a solids retention system, and then into the array of chambers so that an amount of debris and solid contaminants that enter the one or chambers connected to the system is minimized. Solids suspended or entrained in the stormwater are retained by the solids retention system using a combination of settling and filtering actions. When stormwater inflow exceeds a capacity of the solids retention system, the water rises in the diverter to an overflow point at which water flows through a bypass line to the chamber array. Such systems are disclosed in U.S. Patent No. 6,991,734 to Smith et al., titled Solids retention in stormwater system, the entire disclosure of which is hereby incorporated by reference herein. [0008] In another example, related art stormwater management systems may include a subsystem by which stormwater first flows to a primary row of chambers dedicated to capturing a large amount of a debris. The primary row or primary chamber is called an isolator row in a stormwater management system provided Advanced Drainage Systems, Inc. The chamber(s) of the isolator row are encased in a geotextile mesh or filter fabric forming a fine mesh made of any suitable now known or later developed material. The filter fabric encases the chamber, interposing the chamber and the crushed stone floor. Debris and solid contaminants have been found to locally mask and block exit points in the filter fabric, impeding outflow of fluid or water from the chamber into the ground.

[0009] Accordingly, maintenance is required to ensure optimal functionality of chambers, whether they are isolator row chambers, or chambers in system without an isolator row, or chambers in systems with or without other means of debris and solid contaminant collection. Debris is typically manually removed from an interior of a chamber using a device configured to jet water into and through an interior of the chamber to force debris and fluid out of the chamber for collection by vacuum. In particular, jetvac systems use a high pressure water nozzle to propel water through a length of a chamber to suspend and remove sediment. The high pressure spray from the nozzle causes the sediment to exit the chamber into, for example, a connected basin wherein the collected sediment is collected by vacuuming. The jetvac system and similar cleaning devices can snag, tear, or otherwise disrupt the filter fabric material, damaging an efficacy and functionality of the chamber. Accordingly, systems have been designed to protect a floor of the chamber. For example, some systems include a multi-layer mat as an additional component used to protect the filter fabric material during a cleaning and maintenance process.

[0010] Related art chambers used in chamber- type stormwater management systems such as those available from Advanced Drainage Systems, Inc. under the STORMTECH® brand include end caps that attach to, and form a closed end of, the chambers. The ends of the chambers are capped to prevent entry of gravel, earth, or other particulates that would disrupt the filter and drainage functionality of the chamber. The chamber end cap may be formed to include a conduit or pipe stub extending therethrough and defining a channel connecting an interior of the chamber to an exterior thereof. An example end cap and chamber configuration is disclosed by U.S. Patent 7,237,981 to Vitarelli, titled End cap having integral pipe stub for use with stormwater chamber, the entire disclosure of which is hereby incorporated herein by reference.

[0011] Vitarelli discloses a detachable end cap for a molded plastic stormwater chamber with an integrally welded pipe stub. The stub cantilevers outwardly from an exterior surface of the end cap for connection to a line that carries fluid to or from the chamber. The end cap may be formed of polyethylene, for example, for use with a polypropylene chamber.

[0012] Vitarelli discloses an end cap having a convex exterior or dome shaped, which is preferred over planar or flat end caps. Vitarelli discloses ensuring proper fit of the dome shaped end cap to a chamber using flared or flange portions mating with an end of the chamber to close off the chamber and prevent entry of undesired matter.

SUMMARY [0013] A need has been recognized for further enhancing ease of chamber maintenance in chamber- type stormwater management systems. A need has been recognized for a method and configuration that enhances chamber cleaning efficacy to ensure that an interior of chambers is clear of debris that blocks outflow and downward dispersion of fluid from the chamber. It has been found that debris becomes lodged and packed on the back or interior side of the dome shaped, flared end cap. The debris is not easily removed using conventional maintenance techniques including jetting and vacuuming. Additionally, nozzles and other components of jetting and cleaning devices have been found to become lodged and caught on an interior side of the end cap when being extracted from the chamber through a chamber outlet or pipe stub attached to the end cap. Solutions are disclosed including systems, apparatus, and methods that allow the debris to be removed from the chamber during jetting, and prevent debris from collecting on an interior surface side of an end cap of the chamber.

[0014] In an embodiment, a ramp apparatus is provided that is attachable to an interior surface of an end cap of a chamber of a stormwater management system. In this configuration, fluid and solid materials may exit an interior of the chamber by traversing the ramp and passing through an exit defined by the end cap of the chamber. In an embodiment, the ramp is attached to the end cap interior surface and left in place during chamber operation. The ramp is configured to have a shape, form, and profile that is non-obtrusive and does not significantly impede or diminish chamber function. Rather, the ramp is configured to improve chamber function over time by enhancing outflow of solid debris that would otherwise collect at an end of the chamber and block fluid outflow and inflow during operation, and prevent outflow of fluid and solids during maintenance. In an alternative embodiment, the ramp is configured for retrofitting on an interior of, for example, removable end caps. Time savings and costs savings are achieved by preventing clogs in inlets of chambers and achieving substantially complete removal of debris contained therein.

[0015] An embodiment of apparatus useful for chamber- type stormwater management systems includes an inclined surface comprising a first end and a second end. The ramp is configured to connect to a chamber end cap having a stub pipe centrally disposed therethrough. The ramp is connected to the stub pipe at the second end of the ramp, a ramp surface inclined to form a slope rising from the first end to the second end.

[0016] In an embodiment, the apparatus includes support feet. The support feet may be directly connected to the first end of the ramp to provide support to the first end while the second end is supported by the stub pipe to which the ramp is attached or fitted. In an embodiment, a width of the support feet may extend equal to or beyond a width of a bottom of a chamber to which the chamber end cap is fixed.

[0017] In an embodiment, a ramp and end cap system includes a ramp having an inclined surface. The ramp includes a first end and a second end configured to connect to a chamber end cap. The chamber end cap is configured for use in a chamber-type stormwater management system. The chamber end cap has a interior surface to which the ramp is connected, either directly, or by way of a stub pipe passing through the end cap. An interior surface of the end cap faces an interior of a chamber enclosure formed by the end cap when connected to a chamber.

[0018] In an embodiment of a ramp and end cap system, the ramp may include support feet disposed a first end thereof. A ramp surface inclines from the first end to a second end, which is connected to the end cap, for example, at a stub pipe attached thereto. [0019] In an embodiment, a stub pipe is formed to have a cylindrical shape. The stub pipe has a first end and a second end. The second end is configured to extend within a chamber enclosure formed by a chamber connected to the end cap.

[0020] In an embodiment, the ramp is configured to conform to a shape of the stub pipe. In an embodiment, the ramp is fitted directly to the stub pipe, and is configured to form-fit to a portion of the periphery of the stub pipe. In an embodiment, the rap is configured to conform to a periphery at the first end of the stub pipe.

[0021] In an embodiment, the ramp includes a width that is less than a width of a bottom of a chamber to which an end cap connected to the ramp is attached. In an embodiment, the ramp is formed of polypropylene. In another embodiment, the ramp is formed of high density polyethylene. In another embodiment, the ramp is formed of a material selected from the group including steel, stainless steel, aluminum, fiberglass.

[0022] In an embodiment of methods, a process useful for forming a ramp and chamber end cap system include providing a ramp having a first end and a second end, and a ramp surface configured to incline from the first end to the second end, the ramp surface formed to enhance flowability of fluid and passage of debris, the ramp configured to connect to a chamber end cap of a chamber-type stormwater management system. In an embodiment, methods include providing a chamber end cap comprising a stub pipe; and attaching or fitting the ramp to a chamber end cap.

[0023] In an embodiment, methods include providing a chamber useful for stormwater management systems; and attaching the ramp and end cap system to the chamber. In an embodiment, methods include providing a support member attached to or extending from the ramp, the support member configured to support the ram in operation.

BRIEF DESCRIPTION OF DRAWINGS

[0024] The disclosure is shown by way of example in the figures of the accompanying drawings, in which like reference numerals refer to like elements. [0025] FIG. 1 shows a cross-sectional view of chamber configured with a ramp in accordance with an embodiment;

[0026] FIG. 2 shows a perspective overhead view of a chamber end cap;

[0027] FIG. 3 shows a perspective overhead view of a ramp and chamber end cap in accordance with an embodiment; [0028] FIG. 4 shows a perspective overhead view of chamber including a ramp and chamber end cap in accordance with an embodiment;

[0029] FIG. 5 shows a perspective overhead view of a ramp and chamber end cap in accordance with an embodiment;

[0030] FIG. 6 shows a perspective bottom view of chamber including a ramp and chamber end cap in accordance with an embodiment;

[0031] FIG. 7 shows a flow diagram including processes for forming a ramp and chamber end cap system in accordance with an embodiment. DETAILED DESCRIPTION OF EMBODIMENTS

[0032] A solution is provided by embodiments disclosed herein to the recognized need for further enhancing ease of chamber maintenance in chamber-type stormwater management systems, for methods that enhances chamber cleaning efficacy. In particular, apparatus and methods in accordance with embodiments enable effective cleaning of chamber-type stormwater management systems for removing cleaning equipement and sediment and debris. Solutions are disclosed including systems, apparatus, and methods that, inter alia, prevent debris from collecting on an interior surface side of an end cap of the chamber.

[0033] In an embodiment, a ramp apparatus is provided that is constructed and arranged to attach to a chamber useful for a chamber-type stormwater management system. In particular, the ramp is constructed and arranged to attach to an interior surface of an end cap of a chamber of a stormwater management system. In this configuration, fluid and solid materials exit an interior of the chamber by traversing the ramp and passing through an exit defined by the end cap of the chamber. For example, the ramp may be left in place during use of the stormwater system for ready available for periodic cleaning.

[0034] The ramp apparatus is configured to improve chamber function over time, and has a shape, form, and profile that is non-ob trusive and does not frustrate chamber function. For example, the ramp apparatus provides an inclined surface from a ground on which the chamber is positioned to a exit passage at an end of the chamber. The ramp apparatus is shaped to guide fluid and debris through the exit and away from the portions of the chamber interior at which debris and sediment that otherwise collects in related art systems, such as at the end cap interior around the exit of the chamber. [0035] In an embodiment, the ramp is configured for retrofitting on an interior of, for example, removable end caps to form a ramp and chamber end cap system. Stormwater management systems having a ramp apparatus in accordance with embodiments prevent clogs in inlets of chambers and enhance cleaning effectiveness and efficiency

[0036] FIG. 1 shows a cross-sectional view of chamber configured with a ramp apparatus in accordance with an exemplary embodiment. In particular, FIG. 1 shows a ramp and chamber end cap system 100 including an end cap and ramp connected to a chamber configured for stormwater management. A chamber 103 is connected to an end cap, an interior 105 of the end facing an interior of the chamber to form an enclosure when positioned on the ground.

[0037] FIG. 1 shows an interior 105 of the end cap. A ramp 107 is connected to the end cap interior 105 by way of a stub pipe (not shown). The stub pipe is constructed and arranged to provide a passageway from an interior of the chamber 103 to an exterior thereof. The chamber 103 may be of any suitable size and form, and the ramp 107 may be sized and shaped to a particular chamber size or form, and a particular stub pipe size and form.

[0038] The ramp 107 shown in FIG. 1 shows an advantageous configuration wherein the ramp 107 inclines from a first bottom end upwards toward a second top end, relative to a bottom of the connected chamber 103. The ramp 107 is formed to surround a portion of the periphery of the“interior” end of the stub pipe at an interior 105 of the end cap. A surface of the ramp 107 formed to facilitate effective and rapid passage of fluid and materials through the interior end of the stub pipe to exit the chamber 103. [0039] The ramp 107 may take any suitable shape and form that provides an inclined surface extending from a bottom of a chamber enclosure interior to an exit thereof formed by a stub pipe of an end cap. In an embodiment, the ramp 107 is formed of polypropylene or high density polyethylene. In alternative embodiments, the ramp 107 may be formed of materials selected from the group of materials including steel, stainless steel, aluminum, fiberglass, and other like now known or later developed materials.

[0040] The ramp 107 is fastened to the stub pipe at an end thereof that directly connects to the interior of the chamber enclosure. The stub pipe may be formed by any now known or later developed methods and materials and configured for fluid delivery. The stub pipe connected to the ramp 107 shown in FIG. 1 has a cylindrical shape. The ramp 107 may be fastened to the stub pipe by any now known or later developed suitable mechanisms, materials, and methods. In an alternative embodiment, the ramp 107 may be attached directly to the interior 105 of the end cap, or may be attached directly to both the ramp 107 and the interior 105.

[0041] FIG. 2 shows a perspective overhead view of a chamber end cap including a stub pipe 211 extending through an opening defined in the end cap. The end cap is dome shaped and flared, and configured to connect to an open end of a chamber. A first end 211 of the stub pipe 213 extends away from an exterior side surface (not shown) of the end cap, while a second end 215 of the stub pipe 211 extends away from an interior surface 105 of the end cap.

[0042] FIG. 3 shows a perspective overhead view of a ramp and chamber end cap system in accordance with an embodiment. In particular, FIG. 3 shows a ramp and end cap 300 including a flared end cap interior surface 105 and a ramp 107 connected thereto. The ramp 107 is configured and arranged to prevent debris and solid contaminants from collecting and becoming lodged at the interior surface 105 of the end cap. Accordingly, debris and solid contaminants are guided up the ramp and through the passageway defined by the stub pipe 211 during maintenance and cleaning. The ramp 107 prevents the debris and solid contaminants from collecting at the end cap interior surface 105, and guides the debris and solid contaminants along with fluid through an exit from the interior of the chamber provided by the stub pipe 211. Additionally, a nozzle or other component of a jetvac system or other chamber maintenance device will not become lodged and caught on an interior of the end cap.

[0043] FIG. 4 shows a perspective overhead view of a ramp and chamber end cap system in accordance with an embodiment. In particular, FIG. 4 shows an assembled ramp and chamber end cap system 100. The system 100 includes a chamber 103 and with the end cap and ramp apparatus 300 connected thereto.

[0044] FIG. 4 shows an exterior surface 425 of the end cap 300, and a stub pipe 211. The stub pipe 211 includes a first end 213 extending from the exterior surface 425 of the end cap 300. The stub pipe 211 extends transversely through the end cap, with a second, interior end 215 extending away from an interior surface (not shown) of the end cap 300 and communicating with a ramp in an interior of the chamber and end cap configuration. The stub pipe 211 may be welded, for example, at the interface with the end cap surface 425.

[0045] FIG. 5 shows a perspective overhead view of a ramp and chamber end cap in accordance with an embodiment. In particular, FIG. 5 shows a ramp and end cap system 300 as shown in FIG. 3, modified in accordance with an alternative embodiment. FIG. 3 shows a ramp and end cap 300 including a flared end cap interior surface 105 and a ramp 107 connected thereto. The ramp 107 is configured and arranged to prevent debris and solid contaminants from collecting and becoming lodged at the interior surface 105 of the end cap. Accordingly, debris and solid contaminants are guided up the ramp and through the passageway defined by the stub pipe 211 during maintenance and cleaning. The ramp 107 of the embodiment shown in FIG. 5 includes supports or feet 531. [0046] The supports 531 may be configured as shown in FIG. 6 to extend beyond a width of the chamber, and underneath bottom edges of sides of the chamber to which the ramp and end cap 300 is connected. FIG. 6 shows a ramp and chamber end cap system 100 of an embodiment from a bottom perspective view.

[0047] In particular, FIG. 6 shows a ramp and end cap 300 including a flared end cap interior surface 105 and a ramp 107 connected thereto by way of a stub pipe 211. The ramp 107 is configured and arranged to prevent debris and solid contaminants from collecting and becoming lodged at the interior surface 105 of the end cap. Accordingly, debris and solid contaminants are guided up the ramp and through the passageway defined by the stub pipe 211 during maintenance and cleaning. The ramp 107 of the embodiment shown in FIG. 5 includes supports or feet 531.

[0048] FIG. 6 shows an interior surface 637 of the chamber 103. The feet 531 of the ramp 107 are configured to extend under the sides of the chamber. Accordingly, the ramp 107 may be configured to lift relative to the ground to an extent limited by the contact between the feet 531 and chamber walls. Additionally, the feet 531 are constructed and arranged to provide support against the ground or surface upon which the ramp and chamber end cap system rests.

[0049] FIG. 7 shows a process of forming a chamber, ramp and end cap system in accordance with an embodiment. In particular, FIG. 7 shows a method 700 including a step S7001 of providing a ramp having a first end and a second end, and a ramp surface configured to incline from the first end to the second end. The ramp surface is formed to enhance flowability of fluid and passage of debris. For example, the ramp may include a curved surface meeting and conforming with a shape of an end of a cylindrical stub pipe connected to a chamber end cap. [0050] FIG. 7 shows step S7003 of forming feet attached to the ramp. The feet may comprise a same material as the ramp, or a different material, formed to provide a support structure configured to support the ramp in operation. For example, a ramp positioned in a stormwater management system may rest on a ground on which a chamber system is installed. A first, lower end of the inclined ramp may rest on the feet or support structure. In an embodiment, the feet may configured to have a width equal to or larger than a width of a bottom of the chamber. The feet may be configured to be positioned beneath the chamber wall to for additional support. Thus, structural distortion caused by movement of the ramp connected to the chamber system during operation may be minimized.

[0051] Methods including a step S7005 of providing a chamber end cap useful for stormwater management systems. The chamber end cap comprises a stub pipe passing through a central portion of the end cap. Methods include a step S7007 of attaching or fitting the ramp to the chamber end cap. The ramp has a first end, a second end, and a ramp surface inclined from the first end to the second toward the pipe stub when connected thereto.

[0052] The ramp is configured and arranged to prevent debris and solid contaminants from collecting and becoming lodged at the interior surface of the end cap. In an embodiment, the ramp is connected to an interior surface of the end cap. In another embodiment, the ramp is connected to the end cap by way of a third member, for example, attached or fitted to a stub pipe to which the end cap is attached.

[0053] The chamber end cap is configured to attach to the chamber and form a chamber enclosure. In an embodiment, the end cap is welded to the chamber. FIG. 7 shows a step S7009 of attaching the ramp and end cap system to the chamber. The ramp and end cap system are configured to connect to the chamber to form an enclosure containing the ramp. A bottom of the ramp is in facing relation to a ground on which the chamber system is placed. A top surface of the ramp surface is in facing relation to an interior top surface of the chamber. The ramp surface may be curved or otherwise shaped and fitted to the stub pipe to form a smooth, inclined transition from a chamber interior into a stub pipe, the bottom of which is located above a bottom or lower portion of the chamber system.

Claims

CLAIMS WHAT IS CLAIMED IS:

1. A ramp apparatus useful for chamber-type stormwater management systems, comprising:

an inclined surface comprising a first end and a second end, wherein the ramp is configured to connect to a chamber end cap comprising a stub pipe at the second end, and wherein the ramp is configured to fit within a chamber of a chamber-type stormwater

management system.

2. The apparatus of claim 1, the ramp further comprising feet configured to support the ramp, the feet located at the first end of the ramp.

3. A ramp and end cap system, comprising:

a ramp comprising an inclined surface, the ramp comprising a first end and a second end, and configured to connect to a chamber end cap; and

a chamber end cap configured for a chamber-type stormwater management system and having an interior surface facing an interior of a chamber enclosure formed by a chamber and the end cap.

4. The system of claim 3, the ramp further comprising feet configured to support the ramp, the feet located at the first end of the ramp.

5. The system of claim 3, the chamber end cap further comprising:

a stub pipe having a first end and a second end, the second end configured to extend within a chamber connected to the end cap.

6. The system of claim 5, the ramp connected to the end cap by the stub

pipe.

7. The system of claim 5, comprising:

a chamber;

a chamber enclosure comprising the chamber connected to the end cap, the ramp disposed within an interior of the chamber enclosure.

8. The system of claim 7, comprising the ramp directly connected to the stub pipe.

9. The system of claim 8, comprising the ramp directly connected to, and configured to conform to a periphery a the first end of the stub pipe.

10. The system of claim 9, the stub pipe further comprising a cylindrical shape.

11. The system of claim 9, the ramp further comprising:

a ramp surface configured to conform to a shape of the first end of the stub pipe.

12. The system of claim 7, the ramp further comprising a width less than a width of the chamber.

13. The system of claim 10, the ramp configured to be fitted to the cylindrically shaped stub pipe.

14. The system of claim 3, the ramp further comprising polypropylene.

15. The system of claim 3, the ramp further comprising high density polyethylene.

16. The system of claim 3, the ramp further comprising a material selected from the group of materials comprising steel, stainless steel, aluminum, and fiberglass.

17. A method useful for forming a ramp and chamber end cap system, comprising: providing a ramp having a first end and a second end, and a ramp surface configured to incline from the first end to the second end, the ramp surface formed to enhance flowability of fluid and passage of debris, the ramp configured to connect to a chamber end cap of a chamber-type stormwater management system.

18. The method of claim 17, comprising:

providing a chamber end cap comprising a stub pipe; and

attaching or fitting the ramp to the chamber end cap.

19. The method of claim 18, comprising:

providing a chamber useful for stormwater management systems; and attaching the ramp and end cap system to the chamber.

20. The method of claim 17, comprising:

providing a support member attached to or extending from the ramp, the support member configured to support the ramp in operation.