Chemical agent monitor and alarm device

• US 4,578,586 A
• Filed: 01/27/1984
• Issued: 03/25/1986
• Est. Priority Date: 03/30/1983
• Status: Expired due to Term

• Current Assignee: Her Majesty The Queen As Represented By The Minister of National Defence of Her Majesty's Canadian Government
• Original Assignee: Her Majesty The Queen In Right of Canada As Represented By The Minister of National Defence
• Inventors: Preston, Jonathan M.
• Primary Examiner(s): Smith, Alfred E.
• Application Number:
  US06/574,538
• Time in Patent Office: 788 Days
• Field of Search: 250/282, 250/287, 250/379, 250/381, 250/382, 250/386, 250/387, 250/388, 250/336.1, 250/526, 250/288, 250/389, 324/464, 324/465, 324/469, 73/431, 73/864.34, D10/106, D10/81, 374/208, 340/632, 340/693
• US Class Current: 250/382
• CPC Class Codes: G08B 21/12 responsive to undesired emission of substances, e.g. pollution alarms
• CPC Class Codes: G08B 21/14 Toxic gas alarms G08B21/16 takes precedence

Abstract

The specification describes a case for use with a hand-portable chemical agent detector for continuously monitoring an atmosphere for the presence of predetermined chemical agents. The detector having means for ionizing air samples and providing at an output terminal electrical signals representative of the mobility spectrum of ionized chemical vapors produced by the ionizing means. The case comprises means defining a chamber in the case for supporting and removably enclosing the detector, means for communicating ambient atmosphere to the chamber, electrical circuit means in the case, the circuit means being adapted to be detachably connected to the detector output terminal when the detector is positioned in the chamber and being responsive to the electrical signals for producing an alarm signal when the signals detect a chemical agent concentration in the atmosphere exceeding a predetermined concentration level, and alarm means responsive to the alarm signal.

Claims

1. Apparatus for use with a hand-portable chemical agent detector for continuously monitoring an atmosphere for the presence of predetermined chemical agents, said detector having means for ionizing air samples and providing at an output terminal electrical signals representative of the mobility spectrum of ionized chemical vapours produced by said ionizing means, said apparatus comprising:

means defining a chamber in said apparatus for supporting and removably enclosing said detector;

means for communicating ambient atmosphere to said chamber;

electrical circuit means in said apparatus, said circuit means being adapted to be detachably connected to said detector output terminal when said detector is positioned in said chamber and being responsive to said electrical signals for producing an alarm signal when said signals detect a chemical agent concentration in said atmosphere exceeding a predetermined concentration level; and

alarm means responsive to said alarm signal.

2. Apparatus as defined in claim 1, said alarm means including a visual indicator mounted on the exterior of said enclosure.

3. Apparatus as defined in claim 1, said alarm means including an audible indicator mounted in said enclosure.

4. Apparatus as defined in claim 1, said circuit means being further responsive to said signals for producing a further signal representative of the identity of a detected chemical agent and display means mounted on said apparatus and responsive to said further signal for displaying the identity of said detected chemical agent.

5. Apparatus as defined in claim 4, said detector ionizing means including electrical circuit means having an independent d.c. source of power, said apparatus further including a d.c. source of power mounted therein, and means for connecting said detector electrical circuit means to said source of power in said apparatus when said detector is disposed in said chamber.

6. Apparatus as defined in claim 5, said electrical circuit means in said apparatus including means for periodically reversing the polarity of said voltage applied to a drift region in said detector.

7. Apparatus as defined in claim 6, said apparatus including an external connector mean for selectively connecting said electrical circuit means in said apparatus to an external source of power.

8. Apparatus as defined in claim 1, said apparatus being adapted for removably supporting a remote alarm adapted to be connected to the alarm signal output of said circuit means.

9. Apparatus as defined in claim 1, further including, in combination, remote display means adapted to be electrically connected to said electrical circuit means for selectively actuating said circuit means from a location remote from said apparatus, said remote display means having alarm means responsive to said alarm signal.

10. Apparatus as defined in claim 9, said circuit means having means for periodically reversing the polarity of the voltage applied to a drift region in said detector, and said remote display means further including means for selectively activating said polarity reversing means.

11. Apparatus as defined in claim 1, said apparatus further including:

a body portion having a bottom wall adapted to be supported on a generally horizontal support surface, and integral upstanding side walls extending from said bottom wall and terminating in a first edge means, said bottom wall and said side walls having substantially uninterrupted exterior surfaces merging smoothly into one another and means in said first body portion for removably supporting said detector in a predetermined angular position with respect to said bottom wall; and

a lid portion having a top wall and integral side walls depending from said top wall and terminating in second edge means arranged for abutting and mating engagement with said first edge means, said top and side walls having substantially uninterrupted exterior surfaces merging smoothly into one another, said lid portion being adapted to be movably mounted on said first body portion in edge to edge abutting engagement and define therewith an interior chamber for enclosing said detector, said lid portion having air inlet means for admitting ambient air into said chamber.

12. Apparatus as defined in claim 11, said means for removably supporting said detector including an electrical connector secured to said body portion and adapted to be detachably connected to a detector electrical connector having said output terminal.

13. Apparatus as defined in claim 12, said means for removably supporting said detector including a partition removably supported on said body portion side walls adjacent said first edge means and defining with said body portion a second chamber for enclosing said electrical circuit means and a d.c. source of power for said circuit means, said partition including a recess extending into said second chamber for receiving, at least in part, and supporting said detector at an angle to said bottom wall.

14. Apparatus as defined in claim 13, said electrical connector of said apparatus being secured to said partition within said recess.

15. Apparatus as defined in claim 13, said partition having a further recess adapted to removably receive a remote alarm.

16. Apparatus as defined in claim 15, said electrical circuit means including an external power connector secured to one of said body portion side walls for selective detachable connection of said electrical circuit to an external source of power, and a remote alarm connector secured to one of said body portion side walls for selectively communicating said alarm signal to a remote alarm.

17. Apparatus as defined in claim 16, said alarm means including a visual indicator mounted in said top wall of said lid, an audible indicator mounted in said body portion, and a remote alarm adapted to be connected to said remote alarm connector.

18. A chemical agent detecting and alarm apparatus for detecting the presence of predetermined chemical agents in an atmosphere and, if present, the concentration thereof, said apparatus being adapted to be used in a manual mode for analyzing vapours emanating from surfaces and the like suspected of being contaminated by said chemical agents and in an automatic mode for continuously monitoring ambient air, said apparatus comprising, in combination:

a hand-portable chemical agent detector having a housing, a chamber in said housing for ionizing air samples drawn thereinto, a rigid, air inlet probe for communicating ambient air samples to said chamber, an outlet for exhausting said samples from said chamber, pump means for admitting and exhausting said samples into and from said chamber, means responsive to ions produced in said chamber for producing a signal representative of the mobility spectrum of said ions, means responsive to said signal for determining the concentration and identity of chemical in said samples for producing an output signal representative thereof, display means responsive to said output signal for displaying the concentration and identity of detected chemical agents, a connector for outputting said signal produced by said ion responsive means, and a d.c. power supply in said housing for activating electrical circuitry in said detector during use of said detector in said manual mode;

a case for removably enclosing said detector, said case having a main body portion and a lid defining a chamber with said body portion, means within said chamber for detachably connecting said detector to said main body portion, said lid being movable between an opened position whereat said detector may be inserted into and removed from said chamber and a closed position for enclosing said detector, means in said lid for admitting ambient air into said chamber, electrical circuit means in said case having an electrical connector adapted to be detachably connected to said detector connector, said case electrical circuit means being responsive to a signal at said connector for determining the concentration of detected chemical agents and producing an alarm signal when a detected concentration exceeds a predetermined threshold, a d.c. power supply in said main body means for said electrical circuit means and means for connecting said power supply to said means for producing said mobility spectrum when said detector is disposed in said chamber; and

remote display means for selectively activating said circuit means from a location remote from said case, said display means including alarms means responsive to said alarm signal;

said detector being operable in said manual mode independently of said case and said display means, and said detector, said case and said display means being operable as a unit in said automatic mode.