Patent Application
20130047965
The present disclosure generally relates to the field of vehicles and, more specifically, to propulsion systems and modules for vehicles.
Various automobiles and other vehicles include propulsion systems that include an engine and a fuel pump for delivering fuel to the engine. For example, diesel-powered vehicles generally have a propulsion system that includes a diesel fuel combustion engine and a fuel pump module for delivering pressurized diesel fuel to the combustion engine. The fuel pump modules typically have a pressure release device or system to help alleviate pressure build up, for example when the fuel pump is running but the engine is not running. However, existing pressure release devices or systems for vehicle fuel pump modules may not optimally handle large fuel flows in certain situations, such as when the fuel pump is running and the engine is not running.
Accordingly, it is desirable to provide modules that provide for improved pressure relief for a vehicle propulsion system, for example that may better handle large fuel flows in certain situations, such as when the fuel pump is running and the engine is not running. It is also desirable to provide improved vehicle propulsion systems that include such improved modules. It is further desirable to provide improved vehicles that include such fuel pump modules and propulsion systems. Furthermore, other desirable features and characteristics of the present invention will be apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.
In accordance with an exemplary embodiment, a module is provided for a propulsion system of a vehicle, the propulsion system having an engine. The module comprises a fuel pump, a check valve, and a relief valve. The fuel pump is configured to supply fuel flow having a pressure. The check valve is configured to receive the fuel flow from the fuel pump, and to allow passage of the fuel flow to the engine. The relief valve is coupled to the fuel pump, and is configured to release a portion of the pressure of the fuel flow. The relief valve is disposed upstream of the check valve.
In accordance with another exemplary embodiment, a propulsion system is provided for a vehicle. The propulsion system comprises an engine, a fuel pump, a check valve, and a relief valve. The fuel pump is configured to supply fuel flow having a pressure. The check valve is configured to receive the fuel flow from the fuel pump and to allow passage of the fuel flow to the engine. The relief valve is coupled to the fuel pump, and is configured to release a portion of the pressure of the fuel flow. The relief valve is disposed upstream of the check valve.
In accordance with a further exemplary embodiment, a vehicle is provided. The vehicle comprises a drive system and a propulsion system. The propulsion system is coupled to the drive system, and comprises an engine, a fuel pump, a check valve, and a relief valve. The fuel pump is configured to supply fuel flow having a pressure. The check valve is configured to receive the fuel flow from the fuel pump and to allow passage of the fuel flow to the engine. The relief valve is coupled to the fuel pump, and is configured to release a portion of the pressure of the fuel flow. The relief valve is disposed upstream of the check valve.
The present disclosure will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein:
The following detailed description is merely exemplary in nature and is not intended to limit the disclosure or the application and uses thereof. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description.
As depicted in
In certain embodiments (for example, in which the vehicle 100 is a hybrid electric vehicle), the vehicle 100 also includes an energy storage system (ESS) 126 that is mounted on the chassis 112 and is electrically connected to an inverter 128. The ESS 126 preferably comprises a battery having a pack of battery cells. In one embodiment, the ESS 126 comprises a lithium iron phosphate battery, such as a nanophosphate lithium ion battery. Together the ESS 126 and propulsion system(s) 124 provide a drive system to propel the vehicle 100.
The steering system 120 is mounted on the chassis 112, and controls steering of the wheels 116. The steering system 120 includes a steering wheel and a steering column (not depicted). The steering wheel receives inputs from a driver of the vehicle. The steering column results in desired steering angles for the wheels 116 via drive shafts 138 based on the inputs from the driver.
The braking system 122 provides braking for the vehicle 100. The braking system 122 includes a brake pedal (not depicted) for receiving inputs from a driver, and also includes brake units (not depicted) for providing braking torque and friction to stop or slow the vehicle. In addition, driver inputs are also obtained via an accelerator pedal (not depicted) of the vehicle.
The propulsion system 124 is mounted on the chassis 112, and drives the wheels 116. The propulsion system 124 includes the above-referenced engine 132 and fuel pump module 134. In a preferred embodiment, the engine 132 comprises a diesel-fueled combustion engine. The vehicle 100 may also incorporate any one of, or combination of, a number of different types of electrical propulsion systems and/or engines, such as, for example, a gasoline fueled combustion engine, a “flex fuel vehicle” (FFV) engine (i.e., using a mixture of gasoline and ethanol), a gaseous compound (e.g., hydrogen or natural gas) fueled engine, a combustion/engine hybrid engine, and an engine. In certain embodiments, the vehicle 100 also includes a radiator 136 that is connected to the frame at an outer portion thereof and although not illustrated in detail, includes multiple cooling channels therein that contain a cooling fluid (i.e., coolant) such as water and/or ethylene glycol (i.e., “antifreeze”) and is coupled to the engine 132.
As will be appreciated by one skilled in the art, the engine 132 includes a transmission therein, and, although not illustrated, also includes a stator assembly (including conductive coils), a rotor assembly (including a ferromagnetic core), and a cooling fluid or coolant. The stator assembly and/or the rotor assembly within the engine 132 may include multiple electromagnetic poles, as is commonly understood. The engine 132 is integrated such that it is mechanically coupled to at least some of the wheels 116 through one or more of the drive shafts 138.
The fuel pump module 134 provides fuel for the engine 132. As described in greater detail below, the fuel pump module 134 includes a pressure relief system for potentially improved fuel flow and/or release of pressure build-up for fuel flow to the engine 132.
With reference to
The fuel pump module 134 is disposed within a fuel tank 204 of the vehicle. Specifically, the fuel pump module 134 is disposed within a reservoir 206 inside the fuel tank 204. The reservoir 206 is disposed in an interior region of the fuel tank 204, and is surrounded by a wall 208 of the fuel tank 204.
The fuel pump module 134 includes a strainer 210, a fuel pump 212, a check valve 214, and a pressure relief valve 214. The strainer 210 strains or filters the fuel entering the fuel pump 212 through an inlet 201 of the fuel pump 212. The fuel pump 212 pumps and compresses the fuel, and provides a pressurized fuel flow for ultimate use by the engine 132. Specifically, the fuel pump 212 provides the pressurized fuel flow via a first line or path 218. In a preferred embodiment, the fuel pump 212 is a positive displacement, low pressure fuel pump.
The check valve 214 receives pressurized fuel flow from the fuel from the fuel pump 212 (specifically, from an outlet 213 of the fuel pump 212) via the first line or path 215. The check valve 214 allows passage of the pressurized fuel along a second line or path 220 toward the engine 132. Specifically, the pressurized fuel flows from the check valve 214 to the fuel filter 202 via the second line or path 220. The pressurized fuel is filtered by the fuel filter 202, and then flows from the fuel filter 202 to the engine 132 via a third line or path 221 and is then used by the engine 132 for operation of the vehicle.
The relief valve 216 is disposed upstream of the check valve 214. The relief valve 216 is disposed within the fuel tank 204 along with the other components of the fuel pump module 134. The relief valve 216 is disposed between the outlet 213 of the fuel pump 212 and the check valve 214. Unlike certain existing systems, the relief valve 216 is not part of the fuel pump 212 itself, and is not directly physically attached to the fuel pump 212.
The relief valve 216 receives a portion of the pressurized fuel flow from the fuel pump 212 via a fourth line or path 222. During normal operation of the propulsion system 124, pressure release may be provided via pistons of the engine 132. However, under certain conditions (such as under relatively cold temperature conditions, at relatively large flow rates, and/or when the fuel pump 212 is operating but the engine 132 is not running), pressure relief is provided by the relief valve 216. This is particularly applicable for diesel fuel engines, as diesel fuel can cloud up or solidify without such pressure relief as temperatures decrease without such pressure relief.
The fuel pump module 134, including the relief valve 216 thereof, is depicted further in
As shown in
Also as shown in
With further reference to
The valve element 310 rests against the seat 401 when the relief valve 216 is in the closed position. As fluid pressure from the fuel entering the relief valve 216 via the inlet 404 exceeds the spring force of the spring 308, the valve element 310 is moved upward off the seat 401, and fuel flows around the valve element 310 and toward the outlets 406. The fuel then flows out of the relief valve 216 via the outlets 406 and back into the reservoir 206. Conversely, when the fluid pressure from the fuel entering the relief valve 216 via the inlet 404 is less than the spring force of the spring 308, the valve element 310 is seated against the seat 401, the seat 401 seals the relief valve 216, and the fuel is inhibited (and preferably prevented) from flowing around the valve element 310 and toward the outlets 406.
In the depicted embodiment, the valve element 310 comprises a spherical, ball-type element. Also in the depicted embodiment, the relief valve 216 includes six circular outlets 402 disposed circumferentially around a center 502 of a lower surface 504 of the housing 402. In one embodiment, the relief valve 216 opens (and the valve element 310 thereof moves off of the seat 401, to allow fuel flow through the relief valve 216) when the fluid pressure of the fuel flow exceeds five hundred Kilopascals (500 Kpa).
The propulsion system 124, including the fuel pump module 134 thereof, provides for potentially improved pressure release for the propulsion system 124. By having the relief valve 216 disposed upstream of the check valve 214, and between the outlet 213 of the fuel pump 212 and the check valve 214 within the fuel tank 208, a more precise pressure regulation may be attained (as compared with existing systems). The pressure relief provided by the relief valve 216 helps to protect the fuel filter 202 from excess pressure. In addition, these features allow for the relief valve 216 to act similar to a variable orifice when the fuel pump 212 is operating. As such, the fuel pump 212 need not be leak-free when the vehicle is powered (specifically, when the engine 132 is not operating), and therefore does not affect vehicle start times, as may occur with existing systems under certain conditions.
Accordingly, vehicles are provided having improved fuel pump modules. Such fuel pump modules are also provided, along with relief valve systems that are used as part of the fuel pump modules. The disclosed vehicles, fuel pump modules, and relief valve systems include a relief valve positioned upstream of the check valve for improved pressure relief for the fuel pump module.
It will be appreciated that the disclosed vehicles, systems, and devices may vary from those depicted in the Figures and described herein. For example, the vehicle 100, the engine 132, the fuel pump module 134 and/or various components thereof may vary from that depicted in
While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing the exemplary embodiment or exemplary embodiments. It should be understood that various changes can be made in the function and arrangement of elements without departing from the scope of the invention as set forth in the appended claims and the legal equivalents thereof.
