CNG fuel system for a vehicle
10661651 ยท 2020-05-26
Assignee
Inventors
Cpc classification
F02M21/023
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C2225/0123
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C2223/036
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C2223/0123
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C2270/0171
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02D19/027
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C2265/066
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Y02T10/30
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
F17C2227/046
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C13/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Y10T137/474
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B60K2015/0319
PERFORMING OPERATIONS; TRANSPORTING
F17C2225/035
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02M21/0224
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C2250/043
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C2227/041
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B60K2015/03013
PERFORMING OPERATIONS; TRANSPORTING
F02M21/029
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C13/08
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B60K2015/03335
PERFORMING OPERATIONS; TRANSPORTING
B60K2015/03131
PERFORMING OPERATIONS; TRANSPORTING
F02M21/0245
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B60K2015/03309
PERFORMING OPERATIONS; TRANSPORTING
F17C2250/0491
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02M21/0215
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B60Y2200/144
PERFORMING OPERATIONS; TRANSPORTING
F02D19/023
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F17C13/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C13/08
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02M21/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
A fuel management module for use with a CNG fuel system for a vehicle includes a housing configured to be connected to the vehicle and a number of connections, receptacles, and controls associated with the module. A defueling receptacle may be positioned on the front panel of the housing, for defueling a fuel tank of the vehicle. A defueling control valve may be positioned on the front panel of the housing for controlling operation of the defueling receptacle, allowing for selective defueling. One or more high pressure connections may be accessible on the housing and configured for connection to one or more separate fuel tanks in a plug and play configuration. A plurality of filling connections may be accessible on the housing for filling the fuel tank(s). A low pressure fuel output connection may be positioned on the back panel of the housing to provide fuel output from the high pressure connections to the engine.
Claims
1. A vehicle comprising: a chassis having a front portion supporting an operator cab and a rear portion configured for supporting a truck body, the rear portion having a pair of rails extending rearward from the front portion toward a rear of the vehicle; an engine supported by the chassis and configured for utilizing CNG fuel; a fuel management module comprising: a housing mounted on one of the rails of the chassis; first and second high pressure connections accessible on the housing, wherein each of the first and second high pressure connections is an input/output connection configured to permit filling and discharging the CNG fuel through the input/output connection, and wherein each of the first and second high pressure connections is configured for a plug and play configuration; a filling connection accessible on the housing, the filling connection being in communication with the first and second high pressure connections, such that the filling connection is configured to receive input of fuel for filling the CNG fuel through the first and second high pressure connections; and a low pressure fuel output connection accessible on the housing, the low pressure fuel output connection being in communication with the first and second high pressure connections for providing fuel output from the first and second high pressure connections, wherein the fuel management module is further configured such that a fuel tank conduit is alternately connectable to either of the first and second high pressure connections to place the fuel tank conduit in communication with the filling connection and the low pressure fuel output connection via the first or second high pressure connection; and an engine conduit connected to the low pressure fuel output connection and connected to the engine of the vehicle to provide output of CNG fuel discharged through the first and second high pressure connections to the engine through the low pressure fuel output connection.
2. The vehicle of claim 1, further comprising the fuel tank conduit and a first CNG fuel tank mounted on the chassis, wherein the fuel tank conduit connects the first fuel tank to the first high pressure connection of the fuel management module, wherein the first and is alternately connectable to the second high pressure connection, wherein the fuel tank conduit is configured for filling the first fuel tank with the CNG fuel received through the filling connection and for discharging the CNG fuel from the first fuel tank.
3. The vehicle of claim 2, further comprising a second CNG fuel tank mounted on the truck body, and a second fuel tank conduit connecting the second fuel tank to the second high pressure connection of the fuel management module and configured for outputting and receiving fuel to and from the second fuel tank, and wherein the first and second high pressure connections being in communication with the low pressure fuel output connection is further configured for transferring fuel from the second fuel tank to the engine, wherein the second fuel tank conduit is alternately connectable to the first high pressure connection.
4. The vehicle of claim 3, wherein the second fuel tank is a temporary fuel tank.
5. The vehicle of claim 1, wherein the fuel management module further comprises a defueling receptacle positioned on a front panel of the housing, the defueling receptacle configured for connection to defuel one or more fuel tanks of the vehicle through the first high pressure connection, and a defueling control valve configured for selecting among different operations of the defueling receptacle, wherein the defueling receptacle is further configured to be in communication with the fuel tank conduit.
6. The vehicle of claim 1, wherein the fuel management module further comprises at least a second filling connection accessible on the housing, the second filling connection being in communication with the first and second high pressure connections, such that the second filling connection is configured to receive input of fuel for filling the CNG fuel through the first and second high pressure connections wherein the second filling connection is configured to be in communication with the fuel tank conduit.
7. The vehicle of claim 6, wherein the filling connection is a fast fill connection and the second filling connection is a slow fill connection.
8. The vehicle of claim 1, wherein the fuel management module further comprises a pressure regulator in communication with the first and second high pressure connections and the low pressure fuel output connection and configured for regulating a pressure of CNG fuel discharged from the first and second high pressure connections through the low pressure fuel output connection.
9. The vehicle of claim 8, wherein the pressure regulator utilizes a coolant for regulating the pressure of the CNG fuel, and the fuel management module further comprises a coolant connection in communication with the pressure regulator and configured for supplying the coolant to the pressure regulator.
10. The vehicle of claim 1, wherein the fuel management module further comprises one or more valves configured for selectively connecting the first and second high pressure connections to the filling connection and the low pressure fuel output connection for filling or discharge.
11. The vehicle of claim 1, wherein the vehicle is a refuse truck, further comprising a refuse truck body supported by the rear portion of the chassis.
12. A refuse truck comprising: a chassis having a front portion and a rear portion, the rear portion having a pair of rails extending rearward from the front portion toward a rear of the refuse truck; an operator cab supported by the front portion of the chassis; a refuse truck body supported by the rear portion of the chassis; an engine supported by the chassis and configured for utilizing CNG fuel; a fuel management module comprising: a housing mounted on one of the rails of the chassis, the housing having an outer surface; first and second high pressure connections accessible on the housing, wherein each of the first and second high pressure connections is an input/output connection configured to permit filling and discharging the CNG fuel through the input/output connection, and wherein each of the first and second high pressure connections is configured for a plug and play configuration; a plurality of filling connections accessible on the housing, the filling connections being in communication with the first and second high pressure connections, such that the filling connections are configured to receive input of fuel for filling the CNG fuel through the first and second high pressure connections; and a low pressure fuel output connection accessible on the housing, the low pressure fuel output connection being in communication with the first and second high pressure connections for providing fuel output from the first and second high pressure connections, wherein the fuel management module is further configured such that a fuel tank conduit is selectively connectable to either of the first and second high pressure connections to place the fuel tank conduit in communication with the filling connections and the low pressure fuel output connection via the first or second high pressure connection; and an engine conduit connected to the low pressure fuel output connection and connected to the engine of the refuse truck to provide output of CNG fuel discharged through the first and second high pressure connections to the engine through the low pressure fuel output connection.
13. The refuse truck of claim 12, further comprising the fuel tank conduit and a first CNG fuel tank mounted on the chassis, wherein the fuel tank conduit connects the first fuel tank to the first high pressure connection of the fuel management module and is alternately connectable to the second high pressure connection, and wherein the fuel tank conduit is configured for filling the first fuel tank with the CNG fuel received through the filling connections and for discharging the CNG fuel from the first fuel tank.
14. The refuse truck of claim 13, further comprising a second CNG fuel tank mounted on the truck body, and a second fuel tank conduit connecting the second fuel tank to the second high pressure connection of the fuel management module and configured for outputting and receiving fuel to and from the second fuel tank, and wherein the first and second high pressure connections being in communication with the low pressure fuel output connection is further configured for transferring fuel from the second fuel tank to the engine, wherein the second fuel tank conduit is alternately connectable to the first high pressure connection.
15. The refuse truck of claim 12, wherein the fuel management module further comprises a defueling receptacle positioned on a front panel of the housing, the defueling receptacle configured for connection to defuel one or more fuel tanks of the vehicle through the first and second high pressure connections, and a defueling control valve configured for selecting among different operations of the defueling receptacle, wherein the defueling receptacle is further configured to be in communication with the fuel tank conduit.
16. The refuse truck of claim 12, wherein the filling connections comprise a fast fill connection and a slow fill connection.
17. The refuse truck of claim 12, wherein the fuel management module further comprises a pressure regulator in communication with the first and second high pressure connections and the low pressure fuel output connection and configured for regulating a pressure of CNG fuel discharged from the first and second high pressure connections through the low pressure fuel output connection.
18. The refuse truck of claim 17, wherein the pressure regulator utilizes a coolant for regulating the pressure of the CNG fuel, and the fuel management module further comprises a coolant connection in communication with the pressure regulator and configured for supplying the coolant to the pressure regulator.
19. The refuse truck of claim 12, wherein the fuel management module further comprises one or more valves configured for selectively connecting the first and second high pressure connections to the filling connections and the low pressure fuel output connection for filling or discharge.
20. The refuse truck of claim 12, wherein the housing of the fuel management module further comprises a hinged door configured to be moved to cover and uncover a front panel of the housing, and wherein at least the filling connections are accessible on the front panel of the housing.
21. A refuse truck comprising: a chassis having a front portion and a rear portion, the rear portion having a pair of rails extending rearward from the front portion toward a rear of the refuse truck; an operator cab supported by the front portion of the chassis; a refuse truck body supported by the rear portion of the chassis; an engine supported by the chassis and configured for utilizing CNG fuel; a fuel management module mounted on one of the rails of the chassis, comprising: first and second high pressure connections, wherein each of the first and second high pressure connections is an input/output connection configured to permit filling and discharging the CNG fuel through the input/output connection; a plurality of filling connections in communication with the first and second high pressure connections, such that the filling connections are configured to receive input of fuel for filling the CNG fuel through the first and second high pressure connections, wherein the filling connections comprise a fast fill connection and a slow fill connection; a low pressure fuel output connection in communication with the first and second high pressure connections for providing fuel output from the first and second high pressure connections; one or more valves configured for selectively connecting the first and second high pressure connections to the filling connections and the low pressure fuel output connection for filling or discharge; a pressure regulator in communication with the first and second high pressure connections and the low pressure fuel output connection and configured for regulating a pressure of CNG fuel discharged from the first and second high pressure connections through the low pressure fuel output connection; a defueling receptacle in communication with the first and second high pressure connections and configured for defueling CNG fuel discharged through the first and second high pressure connections; and a defueling control valve configured for selecting among different operations of the defueling receptacle, wherein the fuel management module is further configured such that a fuel tank conduit is selectively connectable to either of the first and second high pressure connections to place the fuel tank conduit in communication with the filling connections, the low pressure fuel output connection, and the defueling receptacle via the first or second high pressure connection; and an engine conduit connected to the low pressure fuel output connection and connected to the engine of the refuse truck to provide output of CNG fuel discharged through the first and second high pressure connections to the engine through the low pressure fuel output connection.
22. The refuse truck of claim 21, further comprising the fuel tank conduit and a first CNG fuel tank mounted on the chassis, wherein the fuel tank conduit connects the first fuel tank to the first high pressure connection of the fuel management module and is alternately connectable to the second high pressure connection, wherein the fuel tank conduit is configured for filling the first fuel tank with the CNG fuel received through the filling connections and for discharging the CNG fuel from the first fuel tank.
23. The refuse truck of claim 22, further comprising a second CNG fuel tank mounted on the truck body, and a second fuel tank conduit connecting the second fuel tank to the second high pressure connection of the fuel management module and configured for outputting and receiving fuel to and from the second fuel tank, and wherein the first and second high pressure connections being in communication with the low pressure fuel output connection is further configured for transferring fuel from the second fuel tank to the engine, wherein the second fuel tank conduit is alternately connectable to the first high pressure connection.
24. The refuse truck of claim 21, wherein the pressure regulator utilizes a coolant for regulating the pressure of the CNG fuel, and the fuel management module further comprises a coolant connection in communication with the pressure regulator and configured for supplying the coolant to the pressure regulator.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) To understand the present invention, it will now be described by way of example, with reference to the accompanying drawings in which:
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(16) It is understood that certain components may be removed from the drawing figures in order to provide better views of internal components.
DETAILED DESCRIPTION
(17) While this invention is susceptible of embodiment in many different forms, there is shown in the drawings, and will herein be described in detail, preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated.
(18) Referring now in detail to the Figures,
(19) The truck 10 generally includes a chassis 12 supporting an operator cab 14 and a vehicle body 16. When assembled, the body 16 and the operator cab 14 are mounted on the chassis 12. The chassis 12 is a truck chassis and may have frame members or rail members 11, and the chassis 12 has a front portion 17 for supporting the operator cab 14 and a rear portion 19 for supporting the body 16. In one embodiment, the rail members 11 are made from steel and are generally rectangular in cross-section. The rail members 11 may extend substantially the entire length of the chassis 12 in one embodiment, and may serve as points of support and/or connection for the body 16, the cab 14, the axles 13, and other components. As is known in the art, the chassis 12 has a front axle 13 and one or more rear axles 13 which in turn are attached to wheels 40 for movement of the chassis 12 along a surface. Additionally, as shown in
(20) The chassis 12 may receive several different configurations of the body 16, having various functionalities. As illustrated in
(21) The operator cab 14 generally includes an operator area, which in the embodiment illustrated, includes both a left operator area 50 and a right area 51. The right area 51 may be a right operator area in one embodiment, where the vehicle 10 may be operable in a left or right hand drive configuration and may be switchable between such configurations. In another embodiment, the vehicle 10 may be configured for only left hand or only right hand drive (e.g., for use in the UK), and may also include a side or rear passenger area, depending on the vehicle type. The operator cab 14 may also contain a dashboard 52 that includes controls for operating and monitoring the vehicle 10. The left operator area 50 has a seat 54 for the operator to sit and a left steering wheel 55, as well as an accelerator and a brake (not shown), for operating the vehicle 10 in a left hand drive configuration. The right area 51 may have a right steering wheel (not shown) in one embodiment, as well as an accelerator and a brake actuator (not shown), for operating the vehicle 10 in a right hand drive configuration. In this configuration, the right area 51 provides a standing area for the operator to stand, such as while driving short distances between stops to load refuse. The standing area may include sufficient width and height for the operator to stand while operating the vehicle 10. In this embodiment, the left operator area 50 has a swinging door 57 that closes to secure the operator in the cab 14. The right area 51 may have a similar door 57, or in a vehicle 10 configured for right hand drive, may have opening with a lockable or stowable door (not shown) that can be opened and locked into an open and/or stowed position, to allow the operator easy ingress and egress without the need to repeatedly open and shut the door.
(22) One embodiment of the interior of an operator cab 14 is shown in
(23) A vehicle such as the refuse truck 10 illustrated in
(24) The vehicle control system 60 may further be connected to a fuel control system 71 as described herein, and in one embodiment, the fuel control system 71 may be integrated within the vehicle control system 60. In this configuration, the fuel control system 71 may not be considered a separate system, and may be considered to be part of a single, integrated vehicle control system 60.
(25) One embodiment of the fuel system 70 of the vehicle 10 is illustrated schematically in
(26) The fuel filter 74 is connected to the engine 94, and filters the fuel before the fuel is introduced into the engine 94. The engine 94 typically processes fuel at much lower pressure than the storage pressure in the fuel tanks 72, and thus, the fuel filter 74 may be a low-pressure fuel filter in one embodiment. It is understood that one or more conduits 73 may lead to the fuel filter 74 and/or from the fuel filter 74 to the engine 94.
(27) The fuel management module (FMM) 80 is configured as a central point for management of the fuel within the fuel system 70, including filling and defueling the tank(s) 72 and transferring fuel from the tanks 72 to the engine 94 (and the fuel filter 74, if present). The FMM 80 is illustrated in greater detail in
(28) The FMM 80 in the embodiment of
(29) The FMM 80 in the embodiment of
(30) The FMM 80 in the embodiment of
(31) If multiple fuel tanks 72 are used, the FMM 80 may be configured to permit selective defueling of a single selected tank 72 or multiple tanks 72 simultaneously through the defueling connection 86. Selective defueling or filling may be performed by opening and closing fuel valves, such as respective manual valves 105 and 106 located inside the FMM 80, shown in
(32) The FMM 80 in the embodiment of
(33) The fuel output connection 87 is in communication with the fuel tank(s) 72 and the tank connections 84, and the FMM 80 includes internal components for regulating and depressurizing the fuel between the tank connections 84 and the fuel output connection 87. For example, the FMM 80 includes a shut-off valve 90 that can completely shut off the flow of fuel from the tank(s) 72 to the fuel output connection 87 and the engine 94. In the embodiment of
(34) The FMM 80 may further include gauges, monitors, or other devices for use in monitoring the operation of the FMM 80. For example, the FMM 80 includes a high pressure gauge 98 for monitoring the pressure in the high pressure components of the FMM 80 and a low pressure gauge 99 for monitoring the pressure in the low pressure components of the FMM 80. The high pressure gauge 98 can display an aggregate fuel level in the system, i.e., the total fuel level in any tank(s) 72 that are currently connected to the system (assuming valves 105, 106, 107 are open). The gauges 98, 99 are positioned on the front panel 83 of the housing 81, such that they are covered by the door 82 when closed in one embodiment, but may be positioned elsewhere. The fuel control system 71 and/or the vehicle control system 60 may be connected to the FMM 80, and may display operating parameters of the FMM 80 as well.
(35) The FMM 80 may further be connected with the fuel control system 71, as illustrated in
(36) The fuel control system 71 may also be configured to control operation of the fuel tanks 72 in one embodiment, such as controlling which of multiple fuel tanks 72 are currently used. In an embodiment having two fuel tanks 72, as illustrated in
(37) In one embodiment, the vehicle 10 may be provided from the OEM with a fuel tank 72 mounted on and supported by the chassis 12 and connected to the FMM 80 by a conduit 73 connected to the tank connection 84, and with the FMM 80 connected to the fuel filter 74 by another conduit 73 extending from the fuel output connection 87. The vehicle 10 in this configuration also includes an engine 94, a transmission, wheels 40, and axles 13, and may also include an operator cab 14. In this configuration, the vehicle 10 is provided with a working fuel system 70 that is completely sealed from the fuel tank 72 to the engine 94. Such a complete, sealed installed fuel system 70 can be functionally tested at the OEM before shipping to a body outfitter, which can reduce or eliminate potential system downtime and later fault diagnostics/analysis. Any potential issues can be addressed to a single point of contact for maintenance, repair, and/or replacement as well. The sealed fuel system 70 can also reduce the risk of contamination or dirt ingress into the fuel system 70 during installation of the body 16 or other components. Further, such an installed fuel system 70 can permit the engine 94 to be used to move the vehicle 10 before installation of the body 16 and/or other components. The vehicle 10 provided from the OEM may further include a vehicle control system 60, with the fuel control system 71 integrated into the vehicle control system 60 and connected to the currently installed components of the fuel system 70. The vehicle control system 60 may have a panel display within the operator cab 14 (e.g., as a part of controls 41), which may include a variety of features, including controls for automatically controlling components of the vehicle 10, displays for displaying parameters of the vehicle 10 and its components, and other features. In an embodiment where the fuel control system 71 is integrated into the vehicle control system 60, the panel display may be configured controlling various features of the fuel control system 71 (e.g., solenoid valves 78, 107), displaying various parameters of the fuel control system 71 (e.g., readouts from pressure sensors 79, 108), and/or otherwise interacting with the fuel control system 71. It is understood that the vehicle control system 60 may include connections (e.g., one or more harnesses) that are configured for connection to components that may be subsequently installed, such as the body 16 and related components, or an additional fuel tank 72.
(38) In an additional embodiment, illustrated in
(39) The mounting structure 102 is connected to the chassis 12, and in one embodiment, includes two arms 103 connected to the chassis 12 and extending upward from the chassis 12, and a supporting structure 104 extending between the two arms 103 and supporting the temporary fuel tank 100. More specifically, in the embodiment illustrated in
(40) The use of the temporary fuel tank 100 permits the vehicle 10 to be moved using engine power before manufacturing is complete, such as at the OEM during manufacturing (particularly before the main fuel tank(s) is/are installed) or after the product leaves the OEM. The temporary fuel tank 100 may be a Type 4 CNG tank with a capacity of 7.6 DGE, in one embodiment, which can provide sufficient fuel for mobility during manufacturing. Additionally, the temporary fuel tank 100 and the mounting structure 102 may be removed from the vehicle 10 after manufacturing is complete, or these components may remain connected to the vehicle 10 after the vehicle 10 is in use. The temporary fuel tank 100 may be connected to the FMM 80 through one of the tank connections 84, or the temporary fuel tank 100 may be connected to bypass the FMM 80, depending on the state of construction of the vehicle. A temporary fuel tank 100 may be installed in a different location or configuration in another embodiment.
(41) It is understood that any features described herein with respect to specific embodiments may be utilized with any other embodiment described herein. Such features may be combined if required as well.
(42) The fuel system 70 of the present invention provides benefits and advantages over existing designs. For example, as described above, the FMM provides increased options for customized installation of the fuel system. As another example, a complete and sealed tank-to-engine fuel system provides advantages in testing, function, maintenance, etc., for both the OEM and customers. Integration of the fuel control system with the vehicle control and display system allows for streamlined operation and control design, as well as installation of fuel system controls by the OEM, rather than by body outfitters or other parties in the manufacturing chain. Installation of fuel system controls by the OEM, in turn, provides the ability for more ergonomic and functional control layouts that are integrated into the appearance of the operator cab. Further, installation of the temporary fuel tank can provide advantages in mobility of the vehicle before assembly is complete. Still other benefits and advantages are explicitly or implicitly described herein and/or recognized by those skilled in the art.
(43) While the specific embodiments have been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of the invention, and the scope of protection is only limited by the scope of the accompanying Claims.