I claim:
1. A cellular telecommunications system, comprising, in combination:
a a plurality of cellular radiotelephones each having a predetermined subscriber telephone number;
b at least one local exchange carrier;
c at least one cellular carrier;
d at least one cellular switch in communication with at least one local exchange carrier;
e at least one host computer in communication with said at least one cellular switch;
f processing means resident in the cellular switch for receiving signals from both the at least one local exchange carrier and the cellular carrier and sending signals to both the at least one local exchange carrier and cellular carrier; and
g processing means resident in the at least one host computer for accepting and evaluating a subscriber database comprising a plurality of records representing subscribers to the cellular telecommunication system and including pre-paid account balance information for each subscriber.
2. The cellular telecommunications system of claim 1 further comprising at least one prepaid calling card having an encrypted number which allows a set value of air time to be added to a prepaid subscriber account balance by entering the encrypted number into the prepaid subscriber’s cellular radiotelephone.
3. The cellular telecommunications system of claim 1 further comprising a prepaid account card having an encrypted number which allows a set value corresponding to a monthly access fee to be added to a prepaid subscriber account balance by entering the encrypted number into the prepaid subscriber’s cellular radiotelephone.
4. The telecommunication system of claim 1 wherein said subscriber database further comprises activation and deactivation times for subscriber’s telephone numbers.
5. The cellular telecommunications system of claim 4 wherein the at least one host computer communicates over a local area network.
6. The cellular telecommunications system of claim 4 wherein the at least one host computer communicates over a wide area network.
7. The cellular telecommunications system of claim 4 wherein the subscriber database connected to the at least one host computer is resident on a redundant array of independent devices operably associated with and readable and writable by the at least one host computer.
8. The cellular telecommunication system of claim 1 wherein the at least one local exchange carrier communicates with the at least one cellular switch and at least one host computer over land based telecommunication lines.
9. The telecommunication system of claim 1 wherein the at least one host computer further includes a memory which is used to unload subscriber account information into the memory from the subscriber database, which subscriber account information is decremented im memory during a telecommunications event upon connection with a dialed number.
10. The cellular telecommunications system of claim 4 wherein the processing means outputs an adjusted subscriber account balance information upon completion of the telecommunications event with the dialed number and writes the adjusted subscriber account balance information to the subscriber database thereby updating the subscriber database with the adjusted subscriber account balance information.
11. A method of cellular telecommunications comprising the steps of:
a establishing a prepaid subscriber account balance linked to a predetermined cellular telephone number assigned to a subscriber;
b writing the established prepaid subscriber account balance to a database;
c initiating a cellular telecommunications event by calling a subscriber’s cellular telephone number;
d receiving the subscriber’s cellular telephone number at a cellular switch from a local exchange carrier, the cellular switch recognizing the subscriber’s cellular telephone number as belonging to a pre-paid subscriber;
e sending a first signal from the cellular switch indicating readiness to receive digits comprising the subscriber’s cellular telephone number that was called;
f receiving the first signal at the local exchange carrier and sending a multi-frequency digit string comprising at least a portion of the subscriber’s cellular telephone number to the cellular switch;
g receiving the multi-frequency digit string at the cellular switch and accessing a host computer which is in communication with the subscriber database;
h validating existence of a pre-determined subscriber account balance in the subscriber database that is not subject to any current restrictions based upon the time of day of the telecommunications event;
i establishing communications between the host computer and the cellular carrier to obtain an available telecommunications line and out pulsing the called subscriber’s cellular telephone number only if an affirmative validation at step (h) occurs;
j checking for a connection with the subscriber’s cellular telephone number and, upon occurrence thereof, decrementing the subscriber account balance at regular intervals during the telecommunications event until there is a disconnection with the subscriber’s cellular telephone number; and
k disconnecting the telecommunications event at the host computer upon occurrence of a negative validation at step (h) or a disconnection condition at step (j).
12. The method of cellular telecommunications in claim 11 further comprising the step of adding a set value of air time to the subscriber’s prepaid account balance by entering an encrypted number from a prepaid calling card into a prepaid subscriber’s cellular telephone.
13. The method of cellular telecommunications in claim 11 further comprising the step of adding a set value corresponding to a monthly access fee to the subscriber’s prepaid account balance by entering an encrypted number from a prepaid calling card into a prepaid subscriber’s cellular telephone.
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 fuel blocking valve device, comprising:
a housing to be attached to a fuel tank of a vehicle and having a communication path therein and an upper valve seat inside the housing with a first through hole at a top thereof,
a float valve disposed in the housing for closing the communication path when fuel in the fuel tank flows into the housing, and
a two-way valve disposed in the housing above the float valve for closing the communication path according to an inner pressure of the fuel tank, said two-way valve including a first valve portion disposed at a lower portion thereof for opening the communication path when the vehicle vibrates in a predetermined magnitude, and a second valve portion disposed inside the housing above the first valve portion and having a valve member with a second through hole urged to the upper valve seat for opening and closing the first through hole.
2. A fuel blocking valve device as claimed in claim 1, wherein said first valve portion is a positive valve for opening the communication path when the inner pressure of the fuel tank becomes a predetermined high level, and is formed of a cone shape valve seat, and a spherical member disposed on the cone shape valve seat, said first valve portion opening the communication path when the spherical member rotates.
3. A fuel blocking valve device as claimed in claim 2, wherein said second valve portion is a negative valve for opening the communication path when the inner pressure of the fuel tank becomes below a predetermined low level, said valve member being integrated with the valve seat of the first valve portion to have a space therein, in which said spherical member is disposed.
4. A fuel blocking valve device as claimed in claim 3, wherein said two-way valve is vertically movably located in the housing above the float valve, and the second valve portion is formed in a hollow body having the valve member with the second through hole at a top thereof, said spherical member being disposed in the hollow member.
5. A fuel blocking valve device as claimed in claim 4, wherein said two-way valve further includes urging means situated under the hollow member for urging the same upward.
6. A fuel blocking valve device as claimed in claim 1, wherein said first valve portion is arranged to open the communication path when the inner pressure of the fuel tank exceeds a level higher than a fuel head pressure in a fuel supply pipe when the fuel tank is filled up.
7. A fuel blocking valve device as claimed in claim 1, wherein said housing includes an upper portion for receiving the two-way valve, a lower portion for receiving the float valve, a partition wall for partitioning the upper and lower portions, and an upper lid attached to the upper portion and having said upper valve seat with the first through hole.
8. A fuel blocking valve device as claimed in claim 7, further comprising a supporting bracket, and a holder portion adapted to be attached to a piping and connected to the supporting bracket to communicate with the first through hole, said supporting bracket having a structure such that the housing is assembled to the supporting bracket from a lower side thereof.