What is claimed is:
1. A method of determining the distance between a first electronic device and a second electronic device for allowing a user to access one of the first and the second electronic devices, said method comprising the steps of;
emitting a radio frequency (RF) signal and an audio signal (24) simultaneously from the second electronic device (14),
detecting the RF signal (20) with the first electronic device (12),
detecting the audio signal (24) with the first electronic device (12), and
measuring a time interval (28) between the detection of the RF signal (20) and detection of the audio signal (24) by the second electronic device (14),
said method characterized by comparing the measured time interval (28) to a predetermined time range (38) and enabling one of the first and the second electronic devices in response to the time interval (28) being within the predetermined time range (38) such that the user (52) may have access to the enabled electronic device and disabling one of the first and the second electronic devices in response to the time interval (28) being outside the predetermined time range (38) such that the user (52) cannot have access to the disabled electronic device.
2. A method as set forth in claim 1 including calculating a distance between the first electronic device (12) and the second electronic device (14) utilizing the time interval (28), comparing the distance to a predetermined radius (64), and enabling one of the first and the second electronic devices in response to one of the devices being within the predetermined radius (64) and disabling one of the first and the second electronic devices in response to the devices being outside the predetermined radius (64).
3. A method as set forth in claim 2 wherein the step of emitting the RF signal (20) and the audio signal (24) simultaneously from the second electronic device (14) is further defined by emitting the RF signal (20) at a first velocity and emitting the audio signal (24) at a second velocity simultaneously from the first electronic device (12).
4. A method as set forth in claim 3 wherein the step of emitting the audio signal (24) at the second velocity is further defined by emitting the audio signal (24) at the speed of sound.
5. A method as set forth in claim 3 wherein the step of calculating the distance between the first electronic device (12) and the second electronic device (14) is further defined by calculating the distance by using the measured time interval (28) and the second velocity.
6. A method as set forth in claim 1 wherein the step of emitting the audio signal (24) is further defined as periodically emitting the audio signal (24) for verifying the continued presence of the user (52) within the predetermined time range (38).
7. A method as set forth in claim 1 including measuring the strength of the RF signal (20) and comparing the strength of the RF signal (20) to a predetermined threshold (54) for initiating the measurement of the time interval (28).
8. A method as set forth in claim 7 wherein the step of measuring the strength of the RF signal (20) further includes verifying the presence of the user (52) within the predetermined time interval (28) by comparing the strength of the RF signal (20) to the predetermined threshold (54).
9. A method as set forth in claim 8 wherein the step of emitting the audio signal (24) is further defined as emitting the audio signal (24) for verifying the continued presence of the user (52) within the predetermined time range (38) in response the RF signal (20) falling below the predetermined threshold (54).
10. A method as set forth in claim 1 wherein the steps of emitting and detecting of the RF signal (20) is further defined by emitting and detecting a user code and comparing the user code to an authorized user database having authorized user codes and allowing the user (52) to access the previously enabled electronic device in response to the user code matching an authorized user code.
11. A method as set forth in claim 1 wherein the step of emitting the RF signal (20) is further defined by sequentially emitting the RF signal (20) from a first emitting antenna (42) and a second emitting antenna (44).
12. A method as set forth in claim 1 wherein the step of detecting the RF signal (20) includes detecting the RF signal (20) with a first detecting antenna and a second detecting antenna.
13. A method as set forth in claim 1 wherein the emitting of the RF signal (20) and the audio signal (24) includes emitting the RF signal (20) and the audio signal (24) from a computer (12).
14. A method as set forth in claim 13 wherein the detecting of the RF signal (20) and audio signal (24) includes detecting the signals with a token (70) carried by the user (52).
15. A method as set forth in claim 1 wherein the emitting of the RF signal (20) and audio signal (24) includes emitting the signals from a token (70) carried by the user (52).
16. A method as set forth in claim 15 wherein the detecting of the RF signal (20) and audio signal (24) includes detecting the signals with a computer (72).
17. A security apparatus comprising;
a first electronic device (12),
a first transceiver (16) connected to said first electronic device (12) and having at least one antenna for emitting and detecting a radio frequency (RF) signal,
a first detector (22) connected to said first electronic device (12) for detecting an audio signal (24),
a second electronic device (14),
a second transceiver (30) connected to said second device and having at least one antenna for emitting and detecting a RF signal (20),
a transmitter (34) connected to said second electronic device (14) for emitting an audio signal (24),
a counter (26) connected to said first electronic device (12) for measuring a time interval (28) between a transmitted RF signal (20) and audio signal (24) from said second electronic device (14),
said apparatus characterized by a first processor (36) connected to said first electronic device (12) for comparing the measured time interval (28) to a predetermined time range (38) and enabling one of said first and second electronic devices in response to said time interval (28) being within said predetermined time range (38) and disabling one of said first and second electronic devices in response to said time interval (28) being outside the predetermined time range (38).
18. An apparatus as set forth in claim 17 including a measurement device (64) for measuring the strength of the RF signal (20) detected by said electronic devices and said processor comparing the strength of the RF signal (20) to a predetermined threshold (54).
19. An apparatus as set forth in claim 17 wherein said detector connected to said first electronic device (12) is a microphone (76).
20. An apparatus as set forth in claim 17 wherein said transmitter (34) connected to said second electronic device (14) is a loudspeaker (74).
21. An apparatus as set forth in claim 17 including a second processor (40) connected to said second electronic device (14) for processing said RF signals.
22. An apparatus as set forth in claim 17 wherein one of said first electronic device (12) and said second electronic device (14) includes a user (52) code being emitted with the RF signal (20) and one of said first and second processors includes a database with a plurality of authorized user codes for comparing said user code to said plurality of authorized user codes for allowing the user (52) to access the previously enabled electronic device.
23. An apparatus as set forth in claim 17 wherein said first transceiver (16) includes a first detecting antenna and a second detecting antenna, said first detecting antenna being transverse to said second detecting antenna for increased detection of the RF signal (20).
24. An apparatus as set forth in claim 23 wherein said second transceiver (30) includes a first emitting antenna (42) and a second emitting antenna, said first emitting antenna (42) being spaced apart from said second emitting antenna for sequentially emitting the RF signal (20).
25. An apparatus as set forth in claim 17 wherein said second transceiver (30) includes a third detecting antenna and a fourth detecting antenna, said third detecting antenna being transverse to said fourth antenna for increased detection of the RF signal (20).
26. An apparatus as set forth in claim 25 wherein said first transceiver (16) includes a third emitting antenna and a fourth emitting antenna, said third emitting antenna being spaced apart from said fourth emitting antenna for sequentially emitting the RF signal (20).
27. An apparatus as set forth in claim 17 wherein said first electronic device (12) includes a computer (72).
28. An apparatus as set forth in claim 27 wherein said second electronic device (14) includes a token (70) carried by a user (52).
29. An apparatus as set forth in claim 17 wherein said first electronic device (12) includes a token (70) carried by a user (52).
30. An apparatus as set forth in claim 29 wherein said second electronic device (14) includes a computer (72).
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A removable trigger guard for a firearm, comprising:
a one-piece housing having a gap;
a lock member slidably connected to the housing; and
a lock mechanism attached to the housing for locking the lock member into a position partially within the gap.
2. The removable trigger guard of claim 1, wherein the lock mechanism is a combination lock.
3. The removable trigger guard of claim 1, wherein the gap is a fixedly sized gap.
4. The removable trigger guard of claim 1, wherein the housing comprises a first guard member and a second guard member having the gap therebetween, the first guard member and the second guard member connected by a linking member.
5. The removable trigger guard of claim 4, wherein the linking member comprises a crossbar permanently connecting the first guard member and the second guard member.
6. The removable trigger guard of claim 4, wherein the linking member is disposed outside a trigger guard section of the firearm when the lock member is in a closed position.
7. The removable trigger guard of claim 4, wherein the locking mechanism comprises a combination lock.
8. The removable trigger guard of claim 7, wherein the lock member includes a latching section and the combination lock includes an opposing latching section for engaging with the lock member latching section.
9. The removable trigger guard of claim 1, further comprising a button attached to the housing, the button for releasing the lock member from the position partially within the gap.
10. A removable trigger guard for a firearm, comprising:
a housing comprising an integral first guard member for covering one side of a trigger on the firearm, and an integral second guard member for covering an opposing side of the trigger on the firearm;
a lock mechanism attached to the unitary housing; and
a lock member slidably coupled to the unitary housing for locking the housing onto the firearm.
11. The removable trigger guard of claim 10, wherein the lock member has a U-shape.
12. The removable trigger guard of claim 11, wherein the lock member includes a first shaft with a latching section and a second shaft parallel to the first shaft.
13. The removable trigger guard of claim 10, wherein the locking mechanism is a combination lock.
14. The removable trigger guard of claim 10, further comprising a button coupled to the locking mechanism, the button for releasing the lock member from a closed position to an open position.
15. The removable trigger guard of claim 14, wherein when the locking mechanism is in an open position the button can be depressed, and when the locking mechanism is in a locked position the button cannot be depressed.
16. The removable trigger guard of claim 15, wherein the locking mechanism comprises a combination lock.
17. The removable trigger guard of claim 16, wherein the lock member includes a latching section and the combination lock includes an opposing latching section for engaging with the lock member latching section.
18. A removable trigger guard for a firearm, comprising:
a housing having a fixedly sized gap, the housing adapted to be disposed around a trigger; and
a means for locking the housing to the firearm.
19. The removable trigger guard of claim 18, wherein the housing includes a first guard member and a second guard member, the first guard member and a second guard member fixedly connected by a linking member.
20. A one-piece removable trigger guard for a firearm, the removable trigger guard being configured to fit over the trigger of the firearm and having a lock member held in place over the trigger by a lock.