Coded anti-theft system

Claim 2

A coded anti-theft system for a vehicle comprising: a keyswitch board having a plurality of normally-open keyswitches each having a first contact, a second contact, and a conductive bar and each corresponding to a number; a power supply having a positive terminal and a negative terminal to supply direct current power, said negative terminal being coupled to ground; alarming means having a chargeable battery which is charged by said power supply and grounded at a control terminal thereof, such that when said control terminal is removed from ground, said alarming means sounds; first sensing means comprising a normally-open switch which is installed on a door portion of the vehicle for sensing a door status, such that when the door is closed, said door switch is open, and when the door is open, said door switch is short, triggering said alarming means to sound; second sensing means comprising a normally-closed switch which is installed on an engine hood portion of the vehicle for sensing an engine-hood status, such that when the hood is lifted up more than a predetermined distance, said normally-closed switch opens, triggering said alarming means to sound; indicator means for indicating a status of said system, such that when said indicator means is off, said system is in an alert mode or key-locked mode, and when said indicator means is on, said system is in a disabled mode; starting means for enabling the vehicle to start when said system is in a disabled mode; a power-off relay communicating with said keyswitch board for cutting off required loops of decoding; a power-on relay communicating with said keyswitch board and said power-off relay for forming a required path of decoding; a resetting relay for key-locking communicating with said keyswitch board and said power-on relay; a first coding relay for decoding communicating with said keyswitch board and said resetting relay; a second coding relay for decoding communicating with said keyswitch board and said first coding relay; a holding relay communicating with said power-on relay for holding a temporary grounded path due to a door opening and to error decoding; an alarming relay communcating with said alarming means, said holding relay, and said second sensing means for controlling said alarming means; a limiting timer communicating with said alarming relay for determining a time period for alarming; a delaying timer communicating with said limiting timer for determining a time period from opening of a door until said alarming means sounds; and a driving relay for controlling an energized status of said system communicating with said keyswitch board, said power-on relay, said resetting relay, said first coding relay, said second coding relay, said holding relay, said alarming relay, said limiting timer, said delaying timer, said first sensing means, said indicator means, and said starting means.

Claim 3

A system as claim in claim 1, wherein each said relay and each said timer comprises a relay coil and at least one set of switches which comprises a fixed relay contact, a normally-closed contact, and a normally-open contact, each said relay coil having a positive terminal and a negative terminal.

Claim 4

A system as claim in claim 2, wherein: said power-off relay comprises a first coil, an A-set switch, and a B-set switch; said power-on relay comprises a second coil, an A-set switch, and a B-set switch; said resetting relay comprises a third coil, an A-set switch, and a B-set switch; said first coding relay comprises a fourth coil, an A-set switch, and a B-set switch; said second coding relay comprises a fifth coil, an A-set switch, and a B-set switch; said driving relay comprises a sixth coil, an A-set switch, a B-set switch, a C-set switch, a D-set switch, and an E-set switch; said holding relay comprises a seventh coil and an A-set switch; said alarming relay comprises an eighth coil and an A-set switch; said limiting timer comprises a ninth coil, an A-set switch, and a B-set switch; said delaying timer comprises a tenth coil and an A-set switch; said negative terminal of said power supply, said normally-closed contact of said E-set switch of said driving relay, a negative terminal of said indicator means, and said fixed contact of said holding relay are coupled to ground; said A-set to said E-set switch having a normally-closed contact, a normally-open contact, and a fixed contact; said negative terminal of said power-on relay being coupled to said normally-open contact of said A-set switch thereof and to said normally-closed contact of said B-set switch of said power-off relay; said normally-open contact of said B-set switch of said power-on relay being coupled to said fixed contact of said A-set switch of said resetting relay; said normally-closed contact of said A-set switch of said resetting relay, said fixed contact of said A-set switch of said first coding relay, said fixed contact of said A-set switch of said second coding relay, and said fixed contact of said driving relay being coupled together; said negative terminal of said resetting relay being coupled to said normally-open contact of said A-set switch thereof and to a first diode; said first diode being coupled to said negative terminal of said resetting relay at an anode thereof for limiting ground coupling in a single direction; a cathode of said first diode, said normally-open contact of said B-set switch of said resetting relay, said normally-closed contacts of said B-set switches of said first and said second coding relays, said normally-closed contact of said B-set switch of said driving relay, and a third diode being coupled together; said third diode being coupled to said cathode of said first diode at a cathode thereof and further coupled to said normally-closed contact of said C-set switch of said driving relay at an anode thereof for limiting ground coupling in a single direction; said negative terminal of said first coding relay being coupled to said normally-open contact of said A-set switch thereof and to said normally-closed contact of said B-set switch of said resetting relay; said negative terminal of said second coding relay being-coupled to said normally-open contact of said A-set switch thereof and to said normally-open contact of said B-set switch of said first coding relay; said negative terminal of said driving relay being coupled to said normally-open contact of said A-set switch thereof, to said normally-open contact of said B-set switch of said second coding relay, and to a second diode; a cathode of said second diode being coupled to said normally-open contact of said C-set switch of said driving relay for limiting ground coupling in a single direction; said positive terminal of said power supply being coupled to said positive terminals of said power-off relay, said resetting relay, said first and second coding relays, and said driving relay; said positive terminal of said power-off relay being coupled to said fixed contact of said A-set switch thereof; said positive terminal of said power supply being also coupled to said fixed relay contact of said D-set switch of said driving relay; said positive terminal of said power-on relay being coupled to said normally-closed contact of said A-set switch of said power-off relay; said normally-closed contact of said D-set switch of said driving relay being coupled to said positive terminals of said delaying timer and said limiting timer and said fixed contact of said A-set switch of said limiting timer; said normally-closed contact of said A-set switch of said limiting timer being coupled to said positive terminals of said holding relay and said alarming relay; said switch of said first sensing means having one end thereof coupled to ground and the other end thereof coupled to said fixed contact of said C-set switch of said driving relay; said normally-closed contact of said C-set switch of said driving relay, said anode of said third diode, said negative terminal of said delaying timer, said fixed contact of said A-set switch of said delaying timer, said negative terminal of said holding relay, and said normally-open contact of said A-set switch thereof being coupled together; said normally-open contact of said A-set switch of said delaying timer being coupled to said fixed contact said B-set switch of said limiting timer and said negative terminal thereof; said normally-closed contact of said B-set switch of said limiting timer being coupled to said negative terminal of said alarming relay; said starting means being coupled to ground and to said normally-open contact of said D-set switch of said driving relay, whereby when said driving relay is energized, said D-set switch thereof couples to a loop to actuate said starting means, such that a motor of the vehicle is able to be started; said indicator means being coupled to said normally-open contact of said D-set switch of said driving relay and to ground; said switch of said second sensing means being coupled to ground and to said fixed relay contact of said alarming relay; said normally-closed contact of said A-set switch of said alarming relay being coupled to said control terminal of said alarming means; said control terminal of said alarming means being coupled to said normally-open contact of said E-set switch of said driving relay; said keyswitches having said first contacts thereof being coupled together to said fixed contact of said B-set switch of said power-off relay; said negative terminal of said power-off relay being coupled to a corresponding second contact of one of said keyswitches, thereby defining said keyswitch to be an "off" key; said fixed contact of said B-set switch of said power-on relay being coupled to a corresponding second contact of a keyswitch other than that of said "off" key, thereby defining said keyswitch to be a first decoding key; said fixed contact of said B-set switch of said resetting relay being coupled to a corresponding second contact of a keyswitch other than those of said "off" key and said first decoding key, thereby defining said keyswitch to be a second decoding key; said fixed contact of said B-set switch of said first coding relay being coupled to a corresponding second contact of a keyswitch other than those of said "off" key, said first decoding key, and said second decoding key, thereby defining said keyswitch to be a third decoding key; said fixed contact of said B-set switch of said second coding relay being coupled to a corresponding second contact of a keyswitch other than those of said "off" key, said first decoding key, said second decoding key, and said third decoding key, thereby decoding said keyswitch to be a fourth decoding key.

Claim 5

A system as claimed in claim 3, wherein sequential numbers corresponding to said "off" key, said first decoding key, said second decoding key, said third decoding key, and said fourth decoding key, respectively define a code of said anti-theft system.

Claim 6

A system as claimed in claim 4, wherein said code is changeable.

Claim 7

A system as claimed in claim 3, wherein said positive terminals of said holding relay, said alarming relay, said limiting timer, and said delaying time are coupled to said positive terminal of said power supply; said negative terminals of said holding relay, said alarming relay, said limiting timer, and said delaying timer are grounded, such that when said switch of said first sensing means is on, said alarming system is energized and sound a first alarm; said negative terminals of said holding relay, said alarming relay, said limiting timer, and said delaying timer are grounded, thereby causing said alarming means to sound.

Claim 8

A system as claimed in claim 3, wherein said switch of said second sensing means has one end thereof coupled to ground and the other end thereof coupled to said control terminal of said alarming means to constitute a normally-closed alarming loop, such that when said loop is opened, said alarming means is triggered to provide a second alarm.

Claim 9

A system as claimed in claim 6, wherein said fixed contact of said A-set switch of said holding relay is grounded and said normally-open contact thereof is coupled to said negative terminals of said holding relay and said delaying timer, such that when said switch of said first sensing means is on, said holding relay is in an energized status, enabling said delaying relay to count for a period of time and trigger said alarming means to sound.

Claim 10

A system as claimed in claim 3, wherein said fixed contact of said A-set switch of said holding relay is grounded and said normally-open contact thereof is coupled to said negative terminals of said holding relay and said delaying timer, such that when an incorrect decoding key is keyed in, said third diode is grounded at said cathode thereof which triggers said holding relay to be in an energized status, enabling said delaying relay to count for a period of time and trigger said alarming means to sound.

Claim 11

A system as claimed in claim 3, wherein said keyswitches other than those of said "off" key, said first to fourth decoding keys, are coupled to said negative terminal of said resetting relay, such that when a corresponding key is incorrectly keyed in, said resetting relay is energized, thereby locking all keys except said "off" key.

Claim 12

A system as claimed in claim 3, wherein said third decoding key and said fourth decoding key are respectively coupled to said normally-closed contacts of said B-set switches of said first coding relay and said second coding relay, such that when either of said third decoding key or said fourth decoding key is incorrectly keyed in, said resetting relay is energized, locking all keys except said "off" key.