1. A method of operating a schedule guide system comprising:
accessing abbreviated program schedule information for programs scheduled for a first time duration with the schedule guide system, wherein the system includes a first upgrade module associated with a first authorization, is capable of displaying the abbreviated information, and is permitted by the first authorization to display the abbreviated information;
accessing additional schedule guide information for programs scheduled for a second time duration larger than the first time duration with the schedule guide system, wherein the system is capable of displaying the additional information, but is prevented by the first authorization from displaying the additional information;
generating and displaying an abbreviated schedule guide based on the accessed abbreviated information that the system is permitted to display by the first authorization of the first upgrade module;
replacing the first upgrade module in the schedule guide system with a second upgrade module associated with a second authorization, wherein the second authorization permits the schedule guide system to display the accessed additional schedule guide information; and
generating and displaying a schedule guide based on the accessed additional information that the system is permitted to display by the second authorization of the second upgrade module.
2. The method of claim 1 wherein the second upgrade module is purchased from an operator of the schedule guide system.
3. The method of claim 1 wherein the second upgrade module is purchased from a store.
4. The method of claim 1 wherein the second upgrade module is installed by a user without technical assistance from an operator of the schedule guide system.
5. The method of claim 1 wherein the abbreviated information comprises program schedule information for programs that are currently available for viewing.
6. The method of claim 1 wherein the abbreviated information comprises program schedule information for only a portion of available channels.
7. The method of claim 1 wherein the additional information comprises program schedule information for programs that will be available for viewing at a later time.
8. The method of claim 1 wherein the additional information comprises program schedule information for additional channels.
9. A schedule guide system implemented at least partially on a peripheral device comprising:
circuitry configured to:
access abbreviated program schedule information for programs scheduled for a first time duration, wherein the system is permitted by a first authorization associated with a first upgrade module to display the abbreviated information;
access additional schedule guide information for programs scheduled for a second time duration larger than the first time duration, wherein the system is prevented by the first authorization from displaying the additional information; and
generate and display an abbreviated schedule guide based on the accessed abbreviated information that the system is permitted to display by the first authorization of the first upgrade module,
a second upgrade module associated with a second authorization that permits the schedule guide system to display the accessed additional schedule guide information, and wherein the circuitry is further configured to:
generate and display a schedule guide based on the accessed additional information that the system is permitted to display by the second authorization of the second upgrade module.
10. The schedule guide system of claim 9 wherein the second upgrade module is purchased from an operator of the schedule guide system.
11. The schedule guide system of claim 9 wherein the second upgrade module is purchased from a store.
12. The schedule guide system of claim 9 wherein the second upgrade module is installed by a user without technical assistance from an operator of the schedule guide system.
13. The schedule guide system of claim 9 wherein the abbreviated information comprises program schedule information for programs that are currently available for viewing.
14. The schedule guide system of claim 9 wherein the abbreviated information comprises program schedule information for only a portion of available channels.
15. The schedule guide system of claim 9 wherein the additional information comprises program schedule information for programs that will be available for viewing at a later time.
16. The schedule guide system of claim 9 wherein the additional information comprises program schedule information for additional channels.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A two stroke internal combustion engine comprising:
at least one transfer passage in gaseous communication between a crankcase chamber and a combustion chamber of the engine,
an air passage through a crankcase to the crankcase chamber and in gaseous communication with a carburetor of the engine,
a rotatable circular disk rotatably connected to a crankshaft of the engine,
at least one first rotary shut-off valve located in a radially outermost section of the circular disk bordered by a periphery of the circular disk and operatively disposed between the transfer passage and the crankcase chamber for opening and closing gaseous communication between the transfer passage and the crankcase chamber,
at least one second rotary shut-off valve located on the circular disk bordered by a periphery of the circular disk and operatively disposed between the air passage and the transfer passage for opening and closing gaseous communication between the air passage and the transfer passage, and
wherein the first and second rotary shut-off valves are operably located on the circular disk to close the air passage to the transfer passage when the transfer passage is open between the combustion chamber and the crankcase chamber and to close off the transfer passage between the combustion chamber and the crankcase chamber when the air passage is opened to the transfer passage.
2. A two stroke internal combustion engine as claimed in claim 1 wherein the rotatable circular disk is a crank web, the first rotary shut-off valve is a conical cut out sector in a periphery of the crank web, and the second rotary shut-off valve is a notched cut out in the periphery of the crank web.
3. A two stroke internal combustion engine as claimed in claim 1 further comprising a piston disposed within a cylinder of the engine and connected by a piston rod to the crankshaft and a window in the piston positioned to open and close a transfer port to the transfer passage between the crankcase chamber and the transfer passage for filling the transfer passage with air during air intake.
4. A two stroke internal combustion engine as claimed in claim 3 further comprising a piston passage in the piston and the piston passage being operably located to connect the transfer port to the crankcase chamber.
5. A two stroke internal combustion engine as claimed in claim 3 further comprising a piston passage through the piston and the piston passage being operably located to connect the transfer port to the crankcase chamber.
6. A two stroke internal combustion engine as claimed in claim 5 further comprising a fluid diode in the piston passage which offers resistance for reverse flow of charge into the transfer passage while offering no resistance or minimum resistance for the flow in a direction toward crankcase chamber.
7. A two stroke internal combustion engine as claimed in claim 6 wherein the fluid diode includes a lip around an upper end of the piston passage near the transfer port.
8. A two stroke internal combustion engine as claimed in claim 3 further comprising an inlet port to the cylinder and the inlet port being positioned to allow air-fuel mixture to directly enter the crankcase chamber as the piston is traveling upward.
9. A two stroke internal combustion engine as claimed in claim 1 further comprising the carburetor being a double barrel carburetor with an air-fuel valve to control air-fuel mixture to the inlet port to the cylinder and a separately controlled air only valve to control pure air to the crankcase chamber through the air passage.
10. A two stroke internal combustion engine as claimed in claim 2, further comprising:
the carburetor being a double barrel carburetor,
the carburetor having a air-fuel butterfly valve to control air-fuel mixture to the inlet port to the cylinder and an air only butterfly valve to control pure air to the crankcase chamber through the air passage, and
a link interconnecting the butterfly valves.
11. A two stroke internal combustion engine as claimed in claim 1 further comprising:
a piston disposed within a cylinder of the engine and connected by a piston rod to the crankshaft,
the transfer passage being a first transfer passage,
a second transfer passage, and
a piston passage in the piston and the piston passage being operably located to connect the first transfer passage to the second transfer passage.