Integrated compressor expander apparatus

A fuel cell system wherein a fuel cell stack is supplied with compressed gaseous fluid generated by an integrated compressor/expander apparatus, said apparatus comprising

• a drive shaft;
• an eccentric drive connected to said drive shaft;
• first and second opposing pistons connected to said eccentric drive wherein said first and second pistons are provided with orbital movement;
• walls defining a first traveling chamber holding said first piston and a second traveling chamber holding said second piston, said first and second chambers driven in a reciprocating fashion in one plane through the orbital movement of said first and second pistons;
• an outer case surrounding said first and second traveling chambers;
• first inlet and first outlet ports positioned in said outer case and at least one first chamber port in a wall of said first traveling chamber to connect said traveling chamber with the exterior of said outer case through said first inlet and first outlet ports, said first inlet and first outlet ports opened and closed as said first traveling chamber reciprocates within said outer case;
• second inlet and second outlet ports positioned in said outer case and at least one second chamber port in a wall of said second traveling chamber to connect said traveling chamber with the exterior of said outer case through said second inlet and second outlet ports, said second inlet and second outlet ports opened and closed as said second traveling chamber reciprocates within said outer case;
• said first outlet port connected to supply gaseous fluid compressed in said first traveling chamber to said fuel cell stack;
• said second inlet port connected to receive the exhaust of said fuel cell stack to perform an expander function and return energy to said drive shaft;
• and
• the displacement of said first piston being different from the displacement of said second piston to provide a pressure ratio across said stack.

A fuel cell system wherein a fuel cell stack is supplied with compressed gaseous fluid generated by an integrated compressor/expander apparatus, said apparatus comprising

• a drive shaft;
• an eccentric drive mounted on said drive shaft;
• first and second opposing pistons connected to said eccentric drive wherein said first and second pistons are provided with orbital movement;
• walls defining a first traveling chamber holding said first piston and a second traveling chamber holding said second piston, said first and second chambers driven in a reciprocating fashion through the orbital movement of said first and second pistons;
• third and fourth opposing pistons positioned at 90 degrees from said first and second pistons, said third and fourth pistons connected to said eccentric drive wherein said third and fourth pistons are provided with orbital movement;
• walls defining a third traveling chamber holding said third piston and a fourth traveling chamber holding said fourth piston, said third and fourth chambers driven in a reciprocating fashion through the orbital movement of said third and fourth pistons;
• a fuel cell stack;
• an outer case surrounding said first, second, third and fourth traveling chambers;
• first inlet and first outlet ports positioned in said outer case and at least one first chamber port in a wall of said first traveling chamber to connect said traveling chamber with the exterior of said outer case through said first inlet and first outlet ports, said first inlet and first outlet ports opened and closed as said first traveling chamber reciprocates within said outer case;
• second inlet and second outlet ports positioned in said outer case and at least one second chamber port in a wall of said second traveling chamber to connect said traveling chamber with the exterior of said outer case through said second inlet and second outlet ports, said second inlet and second outlet ports opened and closed as said second traveling chamber reciprocates within said outer case;
• third inlet and third outlet ports positioned in said outer case and at least one third chamber port in a wall of said third traveling chamber to connect said traveling chamber with the exterior of said outer case through said third inlet and third outlet ports, said third inlet and third outlet ports opened and closed as said third traveling chamber reciprocates within said outer case;
• fourth inlet and fourth outlet ports positioned in said outer case and at least one fourth chamber port in a wall of said fourth traveling chamber to connect said traveling chamber with the exterior of said outer case through said fourth inlet and fourth outlet ports, said fourth inlet and fourth outlet ports opened and closed as said fourth traveling chamber reciprocates within said outer case;
• said first inlet port connected to a source of gaseous fluid;
• said first and second pistons connected as a two-stage compressor, said second outlet port connected to supply gaseous fluid air to said fuel cell stack;
• said third and fourth pistons connected as a two-stage expander, said third inlet port connected to receive the exhaust of said fuel cell stack to perform an expander function and return energy to said drive shaft;
• and
• the displacement of said first piston and said second piston being different from the displacement of said third piston and said fourth piston to provide a pressure ratio across said stack.

A system for supplying compressed gaseous fluid to a first device and a second device comprising:

• an outer case for housing first fluid displacement apparatus;
• a first chamber located in said outer case, said first chamber connected to said first device;
• a second chamber located in said outer case, said second chamber connected to said second device;
• a drive shaft extending into said outer case;
• an eccentric drive connected to said drive shaft within said outer case;
• a first piston connected to said eccentric drive, said first piston located within said first chamber;
• a second piston connected to said eccentric drive, said second piston located within said second chamber;
• wherein the volumetric displacement of said first chamber is greater than the volumetric displacement of said second chamber per piston stroke thereby supplying a different volume of gaseous fluid to each of said first and said second devices;
• a third piston connected to said first piston and located 180° therefrom;
• a fourth piston connected to said second piston and located 180° therefrom;
• a third chamber for holding said third piston;
• a fourth chamber for holding said fourth pistons;
• two chambers are connected to supply compressed gaseous fluid to said first device;
• and
• the other two chambers are connected to supply gaseous fluid to said second device.

A system for supplying compressed gaseous fluid to a first device and a second device comprising:

• an outer case for housing first fluid displacement apparatus;
• a first chamber located in said outer case, said first chamber connected to said first device;
• a second chamber located in said outer case, said second chamber connected to said second device;
• a drive shaft extending into said outer case;
• an eccentric drive connected to said drive shaft within said outer case;
• a first piston connected to said eccentric drive, said first piston located within said first chamber;
• a second piston connected to said eccentric drive, said second piston located within said second chamber;
• wherein the volumetric displacement of said first chamber is greater than the volumetric displacement of said second chamber per piston stroke thereby supplying a different volume of gaseous fluid to each of said first and said second devices;
• a third piston connected to said first piston and located 180° therefrom;
• a fourth piston connected to said second piston and located 180° therefrom;
• a third chamber for holding said third piston;
• a fourth chamber for holding said fourth piston;
• and
• three of the four chambers are connected to supply gaseous fluid to said first device and one chamber is connected to supply gaseous fluid to said second device.

A system for supplying compressed gaseous fluid to a first device and a second device comprising:

• and outer case for housing first fluid displacement apparatus;
• a first chamber located in said outer case, said first chamber connected to said first device;
• a second chamber located in said outer case, said second chamber connected to said second device;
• a drive shaft extending into said outer case;
• an eccentric drive connected to said drive shaft within said outer case;
• a first piston connected to said eccentric drive, said first piston located within said first chamber;
• a second piston connected to said eccentric drive, said second piston located within said second chamber;
• wherein the volumetric displacement of said first chamber is greater than the volumetric displacement of said second chamber per piston stroke thereby supplying a different volume of gaseous fluid to each of said first and said second devices;
• a third piston connected to said first piston and located 180° therefrom;
• a fourth piston connected to said second piston and located 180° therefrom;
• a third chamber for holding said third piston;
• a fourth chamber for holding said fourth piston;
• and
• at least one chamber is connected as an expander to receive exhaust from said first device.

A fluid displacement apparatus comprising:

• a drive shaft;
• an eccentric drive connected to said drive shaft;
• a first piston and an opposing second piston, said first piston and said second piston connected together and connected in driven relationship to said eccentric drive wherein said pistons are moved in a reciprocating fashion;
• an outer case;
• a first stationary bore for holding said first piston within said outer case;
• a second stationary bore for holding said second piston within said outer case;
• a first inlet port and a first outlet port connecting said first stationary bore to the exterior of said outer case;
• a second inlet port and a second outlet port connecting said second stationary bore to the exterior of said outer case;
• the displacement of said first piston larger than the displacement of said second piston;
• a fuel cell stack;
• said first stationary bore connected as a compressor to supply compressed gaseous fluid to said fuel cell stack;
• and
• said second stationary bore connected as an expander to receive exhaust from said fuel cell stack, wherein a pressure ratio is produced across said fuel cell stack.

A system for supplying compressed gaseous fluid to a first device and a second device at different pressures from a single fluid displacement apparatus comprising:

• a drive shaft;
• an eccentric drive connected to said drive shaft;
• a first piston and an opposing second piston, said first piston and said second piston connected together and connected in driven relationship to said eccentric drive wherein said pistons are moved in a reciprocating fashion;
• an outer case;
• a first stationary bore for holding said first piston within said outer case;
• a second stationary bore for holding said second piston within said outer case;
• a first inlet port and a first outlet port connecting said first stationary bore to the exterior of said outer case;
• and
• a second inlet port and a second outlet port connecting said second stationary bore to the exterior of said outer case;
• the displacement of said first piston larger than the displacement of said second piston;
• wherein the volumetric displacement of said first bore is greater than the volumetric displacement of said second bore per piston stroke thereby supplying a different volume of gaseous fluid to each of said first and said second devices.

The method of supplying compressed gaseous fluid to a first device and receiving exhaust from said first device to recover energy comprising

• providing a multi-piston fluid displacement apparatus capable of being connected to supply compressed gaseous fluid to said first device from a first chamber and capable of receiving exhaust from said first device in a second chamber, the volumetric displacement of said first and second chambers being different;
• developing a pressure ratio across said first device equal to:
• P R = compressor displacement expander displacement ;
• ⁢ and
• providing variable displacement volume per stroke by altering the eccentricity of an eccentric drive used to drive the pistons.

A system for supplying compressed gaseous fluid to a device comprising

• a two piston fluid displacement apparatus, the volumetric displacement of a first piston greater than the volumetric displacement of a second piston;
• said device connected to receive a supply of compressed gaseous fluid from said first piston acting as a compressor and to supply exhaust to said second piston acting as an expander wherein a pressure ratio is developed across said device equal to:
• P R = compressor displacement expander displacement ;
• wherein said fluid displacement apparatus is driven by an eccentric and wherein eccentricity of said eccentric drive is capable of being varied from a minimum to a maximum value to provide variable displacement apparatus for fluids, the displacement of said pistons proportional to the eccentricity value;
• and
• including control over revolutions per minute wherein two degrees of freedom over the output of said device is achieved by utilizing control over the displacement per revolution with said control over revolutions per minute.