Patent Application
20070193797
The present disclosure relates generally to pressure booster systems and to a pressure booster for a compressed fluid storage tank of an air hybrid system.
Conventional air hybrid systems typically include an engine in fluid communication with a compressed air storage tank. For example, with reference to
Although adequate for most applications, the compression of the air in the storage tank 204 is limited by the characteristics of the engine 202. Thus, the power provided to a system is limited by the pressure of the compressed air in the tank 204. However, for some applications it may be desirable to provide an improved air hybrid system that increases pressure of compressed air.
A pressure booster system including a pressure booster; an engine in fluid communication with the pressure booster; and a compressed fluid storage tank in fluid communication with the pressure booster. The engine provides fluid to the pressure booster and the fluid can be used to compress fluid supplied to the storage tank. A pressure booster system for use with an engine and a method for charging compressed fluid in a storage tank of a system are also disclosed.
Embodiments of the disclosure will now be described, by way of example, with reference to the accompanying exemplary drawings, wherein:
An air hybrid system, according to an embodiment, is generally depicted 10 in
The engine 12, which may also operate as an internal combustion (IC) engine for a motor vehicle, may function as an air compressor that provides a means to operate the pressure booster 16 for charging/compressing a fluid, such as air, in the tank 14. In an embodiment, the pressure booster 16 may include a reciprocating member 34 (e.g., a piston) disposed in a body having a first chamber 36 that is in fluid communication a second chamber 38 by way of an opening 40. Reciprocating member 34 may, for example, include a first end 42 that is connected to a second end 44 by way of a connector or connecting body 46, such as a stem, that may extend through opening 40. In the illustrated embodiment, the first end 42 is disposed in the first chamber 36 and the second end 44 is disposed in the second chamber 38.
The reciprocation of member 34 in the direction of arrow X (see, e.g.,
For example, the opening of the valve 48 (and the closing of valve 50) can initiate a down-stroke of member 34, and the opening of the valve 50 (and the closing of valve 48) can initiate an upstroke of member 34. A valve 52 associated with a first outlet 28 of the pressure booster 16 to exhaust gas/air from first chamber 36 (e.g., to atmosphere A) during an upstroke of the member 34 (i.e., a movement in the direction of arrow X). Valve 54 associated with passage 26 may, if desired be located in proximity to storage tank inlet 24, and may serve to evacuate gas/air from a second chamber 38 for charging/compressing the air in the tank 14. For example, without limitation, valves 48, 52, 64 may be electronically controlled, such as by an intelligent system, and valves 50 and 54 may comprise one-way valves, such as Reed valves. Although valves some of the aforementioned valves are discussed as potentially being electronically controlled and other valves are discussed as potentially being one-way valves, it will be understood by those of skill in the art that the aforementioned valves are not limited by such disclosure and they may instead comprise various other types of valves and/or combinations of valves.
In describing the operation of the pressure booster 16, the first chamber 36 can include a first variable area 56 and second variable area 58, which may comprise the areas (and associated volumes) formed within chamber 36 on opposite sides of first end 42. As illustrated, the reciprocating movement of the first end 42 of the member 34 within the first chamber 36 generally defines or controls the amount of area (and associated volume) associated with each of the first and second variable areas 56,58. The second chamber 38 may also include a first variable area 60 and second variable area 62, which may comprise the areas (and associated volumes) formed within chamber 38 on opposite sides of second end 44. As illustrated, the reciprocating movement of the second end 44 of the member 34 within the second chamber 38 generally defines or controls the amount of area (and associated volume) associated with each of the first and second variable areas 60,62.
During an upstroke of member 34, for example as generally shown in the embodiment illustrated in
During a down-stroke of member 34, for example as generally shown in the embodiment illustrated in
During a down-stroke of member 34 (generally in the direction depicted by arrow Y), air in the second variable area 62 of the second chamber 38 is evacuated generally in the direction depicted by arrow P6 to charge/compress the air in the tank 14. If desired, the area (or volume) of the second chamber 38 can be minimized (relative to the area in the first chamber 36) to increase the resulting pressure of the air in the tank 14. As is known to one skilled in the art, pressure is force per unit area acting on a surface in a direction perpendicular to that surface and is mathematically represented by the equation P=F/A, where P is pressure, F is force, and A is area. As a result, the smaller the area of the second chamber 38, the greater the air (or other fluid) may be pressurized (i.e. charged) in the tank 14. Although the area of the second chamber 38 may vary from application to application, it will be appreciated that the air provided by the engine 12 may be amplified by the pressure booster 16 to any desirable level, such as, for example approximately ten times the pressure provided by the engine air (e.g., 20-bar times 10=200-bar).
Upon completion of the down-stroke of member 34 in the direction depicted by arrow Y, the valve 54 is closed, thereby retaining the relatively high air pressure in the tank 14 in view of the pressure provided by the engine 16 as amplified by the pressure booster 16. When a system, such as, for example, a motor vehicle acceleration or launch-assist propulsion system is operated, a valve 64 associated with passage 68 and, if desired, proximate a tank outlet 66 may be opened so that the charged/compressed air in the tank 14 is provided to the system through passage 68 in the direction generally depicted by arrow P7 (see, e.g.,
According to an embodiment of the invention, exhaust gas from the engine 12 may flow from a passage 70 to the pressure booster 16. The exhaust gas pressure may arise, for example, from engine braking, deceleration, or a turbocharger. As similarly described above, exhaust gas may flow in the passage 70 in the direction depicted by arrow P8 for operating the upstroke of member 34 when the valve 72 is opened so that the exhaust gas may flow through a third pressure booster inlet 74. To operate the down-stroke of member 34, exhaust gas may flow in the passage 70 in the direction generally depicted by arrow P9 when the valve 76 is opened so that the exhaust may flow through a fourth pressure booster inlet 78. If desired, combustible air from the engine and exhaust air from the engine may be simultaneously used to operate the upstroke and down-stroke of the pressure booster 16. Although two passages 22, 70 and four pressure booster inlets 18, 20, 74, 78 are shown, it will be appreciated that the air hybrid system 10 comprise additional configurations and may, for example and without limitation, be reduced to one passage and two inlets for the utilization of combustible and exhaust air.
Referring to
The engine 102, which may also operate as an internal combustion (IC) engine for a motor vehicle, may function as an air compressor that provides a means to operate the upstroke of the pressure booster 106 as a first step in the process of charging/compressing a fluid (e.g., air) in the tank 104. The pressure booster 106 may include a positive displacement pump 118 disposed in a fluid chamber body 120. As illustrated, the positive displacement pump 118 may include a first end 122 and a second end 124. In describing the operation of the pressure booster 106, the air chamber body 120 may include a first variable area (or volume) 126 and second variable area (or volume) 128. As illustrated, the reciprocating movement of the first end 122 of the positive displacement pump 118 within the air chamber body 120 generally defines the associated area (or volume) for the first and second variable areas 126,128.
Referring to
Referring to
As similarly described above, the pressure of the air from the engine 102 according to the path P1 for causing the upstroke pump 118 may be, for example, approximately 20-bar. Although the area of the air chamber body 120 may vary from application to application, it will be appreciated that the air provided by the engine 102 may be amplified by the pressure booster 106 to any desirable level, such as, for example approximately ten times the pressure provided by the engine air (e.g., 20-bar times 10=200-bar).
According to an embodiment of the invention, exhaust gas from the engine 102 may flow from a passage 140 to the pressure booster 106. The exhaust gas pressure may arise from engine braking, deceleration, or a turbocharger. As similarly described above, exhaust gas may flow in the passage 140 in the direction generally depicted by arrow P8 for operating the upstroke of the pump 118 when a valve 142 is opened so that the exhaust gas may flow through a second pressure booster inlet 142. If desired, combustible air from the engine 102 and exhaust air from the engine 102 may be simultaneously used to operate the upstroke and down-stroke of the pressure booster 16. Although two passages 110, 140 and two pressure booster inlets 108, 144 are shown, it will be appreciated that an air hybrid system 100 according to the present invention may take on a variety of additional forms and may, by way of example and without limitation, be reduced to one passage and one inlet for the utilization of combustible and exhaust air.
The present invention has been particularly shown and described with reference to the foregoing embodiments, which are merely illustrative of the best mode or modes for carrying out the invention. It should be understood by those skilled in the art that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention without departing from the spirit and scope of the invention as defined in the following claims. It is intended that the following claims define the scope of the invention and that the method and apparatus within the scope of these claims and their equivalents be covered thereby. This description of the invention should be understood to include all novel and non-obvious combinations of elements described herein, and claims may be presented in this or a later application to any novel and non-obvious combination of these elements. Moreover, the foregoing embodiments are illustrative, and no single feature or element is essential to all possible combinations that may be claimed in this or a later application.
