United States Patent (19)
`Goldstein
`
`(54) DETECTION APPARATUS AND METHOD
`75) Inventor: Mark K. Goldstein, Del Mar, Calif.
`73) Assignee: Quantum Group, Inc. San Diego,
`Calif.
`
`(21) Appl. No.: 595,495
`22 Filed:
`Feb. 1, 1996
`Related U.S. Application Data
`63 Continuation-in-part of Ser. No. 283,550, Aug. 1, 1994, Pat.
`No. 5,596,314.
`(51) Int. Cl. ............. G08B 17/10
`52 U.S. Cl. ...
`... 3401632; 340/628; 340/630;
`429/96; 429/97; 429/98
`58) Field of Search ..................................... 340/628, 630,
`340/632, 633, 634, 635, 693; 220/521,
`522, 254, 293; 429/96.97, 98.99, 100
`
`56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`Re. 30.323 7/1980 Tomioka ................................ 250/335
`2,549,974 41951 Klug .......................................... 23/255
`2,553,179
`5/1951 Farr ........................................... 23/255
`3.027.552
`3/1962 Landis.
`... 340/237
`3,882.477 5/1975 Mueller ........
`... 34.0/50
`4,043.934
`8/1977 Schuler et al.
`... 436/134 X
`4,090,177
`5/1978 Urata et al. ...
`... 340W63OX
`4,144,032
`3/1979 Davis .......
`... 436/168 X
`4,152,551
`5/1979 Hiller ...........
`... 179/107
`4,181,439
`1/1980 Tresch et al. .
`340/630 X
`4,228,428 10/1980 Niedermeyer ........................... 340/628
`4,316,184 2/1982 Nagel .......
`340/63OX
`4,319.234
`371982 Rice ........................................ 340/628
`4,401,978
`8/1983 Soloman ..........
`340/63OX
`4539,556 9/1985 Dederich et al. .
`... 34.0/630
`4,688,021
`8/1987 Bucket al. ...
`... 340/632
`4.769.550 9/1988 Dolnick .....
`... 250/574
`4,839.014
`6/1989 Park et al. ....
`... 204/265
`4,845,474 7/1989 Moore et al
`340/629
`4,870,395 9/1989 Belano ..
`340/693
`4,959,640 9/1990 Hall .......
`... 340/693
`5,063,164 11/1991 Goldstein .
`... 436/169
`5,103.216 4/1992 Sisselman
`... 340/693
`5,172,042 12/1992 Singhal ............................... ... 3262
`
`
`
`US00579.3295A
`Patent Number:
`11
`45) Date of Patent:
`
`5,793,295
`Aug. 11, 1998
`
`5,208, 16 5/1993 Joh ............................................ 429/96
`5,280,273
`1/1994 Goldstein
`... 340/632
`5,290,639 3/1994 Mallory .............
`o
`429/1
`5,302,350 4/1994 Goswami et al.
`... 422/86
`5,327,119 7/1994 Ishii ..................
`... 340/629
`5,346,671
`9/1994 Goswami et al.
`... 422/86
`5,367,575 11/1994 Dieken et al. .
`... 381/67
`5,394,094 2/1995 Wagner ..
`... 324,556
`5,396.221
`3/1995 Bridges .........
`... 340/628
`5,405.583 4/1995 Goswami et al
`... 422/86
`5,445,900 8/1995 Miller Jr. .................................... 429/1
`5,521,022 5/1996 Petzl.......
`... 429797
`5592,147 1/1997 Wong ...
`... 340,632
`5,596,314 1/1997 Goldstein ............................... 340/632
`FOREIGN PATENT DOCUMENTS
`39761 11/1981 European Pat. Off. ............... 340/630
`2241985 9/1991 United Kingdom ....................... 7/10
`OTHER PUBLICATIONS
`Drager: Detector tube handbook 4th Edition 1979 pp. 30.82.
`ESP-Alert Carbon Monoxide/Smoke detector.
`COSTAR (TM) Carbon Monoxide Alarm, Quantum Group
`Inc.,
`Primary Examiner-Jeffery A. Hofsass
`Assistant Examiner-Ashok Mannava
`Attorney, Agent, or Firm-Niro, Scavone. Haller & Niro
`57
`ABSTRACT
`A detector sensor system for sensing the presence of a toxic
`gas, such as carbon monoxide and/or smoke whereby a
`corresponding alarm is sounded. The presence of the gas is
`detected by passing light through a biomimetic sensing
`material in which the optical characteristics change in the
`presence of the target gas. This system includes a housing
`containing a light emitter, light detector and a mechanism for
`sounding an alarm. The sensing material is contained in a
`cell which, together with a battery to power the system, is
`mounted in a key insertable into the housing. The key may
`be readily inserted or withdrawn from the housing for
`replacement purposes. When fully inserted, the key posi
`tions the sensing cell means between the light emitter and
`detector means and brings the battery contacts carried there
`with into connection with contacts associated with the
`system circuitry mounted within the housing.
`
`23 Claims, 3 Drawing Sheets
`
`FIRST ALERT & BRK EXHIBIT 1041
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`U.S. Patent
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`Aug. 11, 1998
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`Sheet 1 of 3
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`5,793,295
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`FIGURE 1
`12
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`U.S. Patent
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`Aug. 11, 1998
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`Sheet 2 of 3
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`5,793,295
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`FIGURE
`
`FIGURES
`18
`12
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`-
`a
`34-7 E-Z 34.
`22 2. 22
`- Ž 26
`44
`(7 N-46
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`FIGURE 7
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`2,363
`2.E-ZZZ 22, 2
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`Fr.
`E.
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`FIGURE 8
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`U.S. Patent
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`Aug. 11, 1998
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`Sheet 3 of 3
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`5,793,295
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`FIGURE 9
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`1
`DETECTION APPARATUS AND METHOD
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`5,793.295
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`2
`tions for removal from the separate drawer carrying the
`sub-combination, and then only after the drawer has been
`withdrawn from the housing. Of course, the same type of
`two-step process is required to insert a replacement battery/
`cell sub-combination into the drawer and to then engage the
`drawer in the housing. Therefore, there is a continuing need
`for an even simpler means of replacing the battery and
`sensor of a gas detection system. Such a solution should
`allow for detectors of one or more gases, promote efficient
`detector operation, allow the unit to be easily serviced,
`clearly show when the battery and sensor is missing and be
`attractively configured.
`BRIEF DESCRIPTION OF THE INVENTION
`The present invention is for use with gas detection sys
`tems that require a means for the convenient replacement of
`the battery and/or gas sensor. The invention comprises an
`enclosure formed by a generally flat first panel connected to
`a second panel by a sidewall. The enclosure has a generally
`rectangular opening into which a generally flat and rectan
`gular "key" can be inserted. As used herein, a "battery key"
`comprises a power source, such as a standard 9 volt battery
`or one or more conventional AAA or AA size batteries and
`means for electrically connecting the power source to the
`electronics of a gas detection system. A "battery/sensor key"
`comprises the addition of an optical gas sensor to a battery
`key for the gas to be sensed. For the purposes of this
`disclosure, the term "key" is used generally to indicate either
`a battery key or a battery/sensor key as the example dictates.
`The rectangular opening in the enclosure has a pivotably
`mounted door having an outwardly curved flange. The
`outwardly curved flange bears brightly colored indica and
`serves to warn persons in the vicinity of the absence of the
`key being insertably mounted within the housing.
`Upon full insertion of the key into the housing, an
`electrical connection between the power source (contained
`within the key) and the remainder of the gas detection
`system (mounted within the housing) is made. If the key is
`a battery/sensor key, the optical sensor(s) for target gas(es)
`contained therein are optically aligned between a light
`emitting means and a light detecting means so as to provide
`detection of the target gas if exposure occurs.
`Replacement of a key is easily accomplished by pressing
`an external ejection button which causes the key to partially
`but substantially eject from the surrounding enclosure or
`housing. The user then simply grips and slides the old key
`out of the enclosure to thereby remove it. A new replacement
`key is inserted into the enclosure or housing in a manner
`similar to inserting a floppy disk into a personal computer.
`that is to say by sliding the replacement key into the
`rectangular opening and pressing lightly to engage a locking
`mechanism which operates to secure the key in place.
`The second embodiment of the present invention is
`directed to an enclosure for a combination target gas-smoke
`detector in which the presence of a hazardous target gas,
`such as carbon monoxide and/or the presence of smoke can
`be detected. An optical target gas sensor is used to determine
`the presence of the target hazardous gas. The presence of
`smoke is determined by the reflection of light by smoke
`particles.
`The advantage of replacing the battery or battery/sensor
`combination without having to remove a drawer or remove
`the enclosure or housing from a wall or ceiling is a clear
`improvement over the present state of the art. This new
`invention allows one to effect such a replacement using only
`one hand thereby leaving the other hand free for safety
`purposes, e.g. to hold onto a ladder or to brace oneself on a
`nearby wall.
`
`CROSS REFERENCE TO RELATED
`APPLICATION
`This application is a continuation in part of U.S. appli
`cation patent Ser. No. 08/283,550, filed Aug. 1, 1994, now
`U.S. Pat. No. 5,596,314. All the disclosure of copending
`application 08/283.550 is incorporated herein by reference.
`BACKGROUND
`The invention relates to gas detection systems such as
`carbon monoxide detectors mounted on walls or ceilings in
`residential applications.
`Airborne gases and vapors which are hazardous or oth
`erwise dangerous, such as propane, methane, carbon
`monoxide, mercury vapor, ethylene oxide, hydrogen sulfide,
`and other hazardous gases, are sometimes difficult to detect,
`especially where they are odorless or present at levels that
`cannot be smelled, or are masked by other odors. The danger
`of these hazardous gases is becoming increasingly apparent,
`especially in industrial plants, mines, environmentally
`sealed homes and office buildings, recreational and other
`vehicles and other environments in which people are present
`for long periods of time.
`A solid-state biomimetic sensor has been developed
`which has an extended lifetime and which mimics the
`human response to various toxic gases and vapors. As
`disclosed by Goldstein in U.S. Pat. No. 5,063,164, the
`contents of which are hereby incorporated by reference, a
`biomimetic sensor comprises a porous, semitransparent sub
`strate impregnated with a self-regenerating chemical sensing
`reagent. The presence of target gases is determined by
`measuring the change in optical density of the sensor when
`exposed to the target gas. The sensor has a relatively long,
`useful lifetime, typically greater than three years.
`Other gas sensing compositions have been disclosed in
`several issued U.S. Patents such as Ser. No.: 4,043.934,
`5.302,350, 5346,671. 5.405,583. Generally the disclosed
`sensors are useful for detecting certain gases, such as
`reducing gases like carbon monoxide, by producing a color
`change upon exposure to an atmosphere containing the
`target hazardous gas.
`A gas detector system which uses the above described
`Goldstein biomimetic sensor has been disclosed in U.S. Pat.
`No. 5.280,273. The gas detector system includes a housing
`containing a light emitter, a light detector and a mechanism
`for sounding an alarm. The target gas sensor is contained in
`a battery/sensor cell, which also comprises a battery to
`power the system. The cell is inserted into a drawer which
`when so combined is slid into the housing for the system.
`The system housing has openings in it thereby permitting
`ambient air to reach the sensor and sound generated by the
`alarm to escape. When fully inserted, the drawer positions
`the gas sensor between a light emitter and a light detector
`and simultaneously brings the battery into electrical con
`nection with contacts for the alarm and light system. The
`drawer is configured so that it cannot be inserted without a
`battery/sensor cell in place. As a separate unit the battery/
`sensor cell sub-combination may be replaceably inserted
`within the drawer.
`Although the above described 273 configuration has had
`significant market success, replacement of the battery/sensor
`sub-combination may be difficult in a relative sense for the
`elderly or persons with a disability. For example, the sub
`combination package may be grasped at only limited loca
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`3
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIG. 1 is a partially cut away, perspective view drawing
`showing the first embodiment of the present invention.
`FIG. 2 is a partially cut away, top view drawing showing
`the first embodiment of the present invention.
`FIG. 3 is a cross sectional drawing showing the enclosure
`of the present invention taken about 3-3 of FIG. 2.
`FIG. 4 is a perspective view drawing showing the inverted
`top side (with respect to FIG. 3) of the battery/sensor key of
`the present invention.
`FIG. 5 is a cross sectional view drawing showing the
`optical alignment of two gas detector sensors with a light
`emitting means and a light detecting means within the
`enclosure of the present invention.
`FIG. 6 is a cross sectional view drawing showing an
`alternative embodiment of FIG. 6.
`FIG. 7 is a partial perspective view drawing of another
`embodiment of the present invention.
`FIG. 8 is a side view of the key of the embodiment.
`FIG. 9 is a partially cut away, top view drawing of a
`further embodiment of the present invention.
`DETALED DESCRIPTION
`As seen in FIGS. 1, 2 and 3, the first embodiment of the
`present invention comprises an enclosure 10 formed by a
`generally flat first panel 12 and a second panel 14 spaced
`apart from the first panel 12 by a sidewall 16. The space in
`the enclosure is sized to house the circuit board and other
`components of a gas or smoke detection system 18. A large
`variety of configurations for the enclosure are possible
`including, square, rectangle, round, round with one flat edge,
`etc.
`The detection system shown in FIG. 1 may be a simple
`smoke alarm with a conventional battery to be replaced, or
`it may be an optically based target gas(es) detection system,
`or it may be a more complex detection system that detects
`both smoke and target gas(es). In all cases the device
`responds to the presence of smoke and/or one or more target
`gases by the triggering of an alarm system within the
`detection system which may sound an audible alarm, such as
`a buzzer, beeper or other sound making means, or other
`suitable safety responses, such as activating a safety shutoff
`valve or a combination of the audible alarm and activation
`responses.
`For the purposes of the following exemplary embodiment,
`a target gas detection system that requires a combination
`battery/sensor key is disclosed. The illustrated example
`could be adapted for use with a smoke detection system or
`a combination target gas(es)/smoke detection system.
`As shown in FIG. 1. a plurality of slots 20 are provided
`in the enclosure to allow ambient air to freely flow into the
`enclosure, thus reaching the target gas sensor 22 contained
`in a battery/sensor key 26. The slots also serve as a means
`for allowing any sound generated by an internal audible
`alarm to escape the enclosure.
`On the exterior of the enclosure at least one light emitting
`means 24, such as a light emitting diode (LED), is provided
`to indicate the presence of any target gas(es) or smoke.
`Typically the LED is brightly colored so as to catch the eye
`when activated by the electronics of the gas detection
`system.
`A generally rectangular opening 21 is provided in the
`sidewall 16 of enclosure 10 and is configured to accept the
`battery/sensor key 26, which itself has a generally and
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`correspondingly flat rectangular configuration. Within the
`opening is a pivotably mounted door, which is described in
`greater detail hereinbelow.
`The battery/sensor key 26 comprises a power source 28,
`such as integrally housed one or more conventional AAA or
`AA batteries as shown in FIGS. 2 and 3, electrically con
`nected to contact pads 30 on the "inverted side" of the
`battery/sensor key (shown in FIG. 4). Electrical contact
`between the power source 28 within the battery/sensor key
`26 and contact means 32 on the electronics circuit board of
`the target gas detection system 18 is made upon the full
`insertion of the key into the enclosure via contact pads 30.
`The battery/sensor key further comprises at least one
`target gas sensor 22 contained within a window 34 in the
`battery/sensor key. As shown in FIG. 3, light 36 from a light
`emitting means 38, such as an LED mounted on the gas
`detection system circuit board 18, passes through the win
`dow in the battery/sensor key and through the sensor 22
`contained therein. The attenuated light is then detected by
`light detecting means 40, such as a photodiode, mounted on
`a daughter board 42 that is affixed to the second panel 14 of
`the enclosure. The daughter board is an integrated part of the
`gas detection system and is in electrical contact (not shown)
`with the electronic components of the gas detection system.
`As shown in FIGS. 4 and 5, a plurality of target gas
`sensors 22, 23 and windows 34, 35 may be provided thereby
`allowing the gas detection system to detect multiple target
`gases (second sensor shown in dotted line in FIG. 4). In the
`particular embodiment of the battery/sensor key shown in
`FIG. 5, light from the light emitting means 38 on the gas
`detection system circuit board 18 passes through a window
`34 containing the first sensor 22. The singly attenuated light
`is reflected in turn by reflecting means 44 and 46.
`respectively, and is redirected through the second window
`35 containing the second sensor 23. The doubly attenuated
`light is then detected by light detecting means 40, such as a
`photodiode, on the gas detection system.'s circuit board 18.
`In this manner, the sensors 22 and 23 may detect different
`toxic gases or, for example, may detect different ranges of
`the same toxic gas.
`A variation of this embodiment of the battery/sensor key.
`is shown in FIG. 6 in which a single reflecting means 44A
`is part of a battery/sensor key 26A along with one sensor
`22A.
`As an aid in the handling and gripping of the batteryl
`sensor key during replacement, portions of the outermost
`distal end of the battery/sensor key contain grips 48 as
`shown in FIGS. 1.2 and 4. Typically the grips are in the form
`of small ridges or grooves provided on the surfaces of the
`battery/sensor key.
`As presently contemplated, the generally rectangular
`opening 21 in the enclosure has a pivotably mounted enclo
`sure door 50 with an outwardly curved flange 52 which
`serves several functions (shown in FIGS. 1 and 3). When the
`battery/sensor key is not inserted in the enclosure, the
`outwardly curved flange 52 or flag is clearly and promi
`nently visible. The surface of the flange 52 is brightly
`colored or bears brightly colored indica, warning people in
`the vicinity that system is not powered. Upon insertion of the
`battery/sensor key 26 into the opening 21 (FIG. 1) the flange
`52 has been designed to engage the leading end 27 of the
`battery/sensor key and thereby pivot the enclosure generally
`designated door 50 into the enclosure 10. Upon full insertion
`of the battery/sensor key 26 (shown in FIGS. 2 and 3), the
`flange 52 on the enclosure door 50 remains in contact with
`the surface 29 of the key 26 by means of a spring (not
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`shown) and thereby helps prevent dust or bugs from entering
`the enclosure 10.
`Upon the full insertion of the battery/sensor key 26 into
`the enclosure 10, several simultaneous events occur as
`shown in FIG. 3. The trailing edge 54 of the key 26 has been
`designed to engage a locking lip 56 along the edge of the
`rectangular opening 21. The flange 52 (in contact with the
`lower surface 29 of the key 26 in FIG. 3) may be designed
`to flexibly bias the key 26 into a locked disposition behind
`lip 56. Simultaneously, the upright 58 of a pivotably
`mounted ejection means generally designated 59 is
`depressed by the surface 61 of the battery/sensor key 26. An
`ejection button 60 on the other end of the ejection means 59
`is thereby forced to extend above the surrounding surface or
`rim 61 of the enclosure 10. Upon pressing the ejection
`button 60 in an upwardly or counterclockwise direction as
`illustrated, the upright 58 moves the battery/sensor key 26 in
`such a manner that the trailing edge 54 of the battery/sensor
`key 26 disengages from behind the locking lip 56 along the
`edge of the rectangular opening 21. This combination of
`actions provides for selective engagement and
`disengagement/ejection of the key from the enclosure 10.
`Compression means 62, such as a spring, assists not only in
`the trailing edge 54 engaging the locking lip 56, but also in
`the substantial, partial ejection of the key 26 out of the
`enclosure 10 upon release of the key 26 effected by the
`ejection means 59. Substantial, partial ejection of the key 26
`indicates to a user that the system is not operable. Further.
`separate alarms may be provided to detect low power level
`or sensors in need of replacement. Typically, the battery
`source will require replacement of the key before the sensor
`(s). However, substantial exposure to the gases being sensed
`could result in the expended sensor requiring replacement of
`the key before the battery.
`Upon full insertion of the battery/sensor key (as shown in
`FIG. 3), contact means 32 on the circuit board 18 of the gas
`detection system come into electrical contact with the con
`tact pads 30 on the surface of the key 26. This action
`provides electrical power from the key's power source 28 to
`the electronic components of the gas detector system.
`Lastly, upon full insertion of the battery/sensor key, the
`optical sensors 22 contained within the windows of the key
`are brought into optical alignment with the light emitting
`means 38 and the light detecting means 40 of the gas
`detection system. This allows the gas detection system to
`monitor the optical characteristics of the sensor disk and
`thus detect the presence of target gas(es).
`Given the above disclosure, one skilled in the art would
`recognize that the replacement of an integral power source
`and gas sensor has been greatly simplified. Replacement of
`the battery and/or battery/sensor key is a relatively easy
`process which does not require special skills or tools.
`Removal of the battery sensor key is accomplished by
`pushing the ejection button 60, which causes the battery/
`sensor key to release from behind lip 56 and to partially and
`substantially eject from the enclosure. The key is removed
`from the enclosure by simply gripping the protruding por
`tion and pulling the remainder of the key out. Upon removal
`of the battery/sensor key, the enclosure door closes, promi
`nently displaying the outwardly curved flange. This latter
`feature serves to warn persons within sight of the gas
`detection unit that the unit has been deactivated by virtue of
`no key being in place. Additional warning devices could be
`included within the system to warn users that a charged
`battery is not inserted or not fully inserted. Such devices
`(e.g., buzzers, blinking lights and the like) are well known.
`A replacement key is simply inserted into the generally
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`rectangular opening of the enclosure in a manner similar to
`inserting a magnetic storage disk into a personal computer.
`Therefore only a slight, inward pushing force is needed to
`fully engage the battery/sensor key as the spring means 62
`that helps to eject the key 26 is being compressed and the
`trailing edge of the key is engaging the locking lip of the
`enclosure opening. The total amount of force required to
`insert a replacement key is very slight and therefore even the
`most feeble person can successfully insert the battery/sensor
`key with one hand.
`An alternative embodiment of the smoke or gas detector
`enclosure is shown in FIG. 7 in which the key 26B is just a
`battery 64 as encountered for example in a smoke detector.
`As shown in this alternative embodiment, the battery 64 may
`be a commonly available conventional 9 volt battery. The
`mechanisms of this unit are analogous to the components
`and interaction of components described above. Another
`embodiment is shown in FIG. 8 in which a slidable flag 52c
`appears when the battery is removed. Flag 52c is biased
`outwardly by compression spring 62c. When battery 64 is
`pushed inwardly so that contacts 30c and 32c mate, spring
`62c is compressed and flag 52c is held within the housing by
`abutment of battery 64 against the upward lip 67 on the
`leading edge of flag 52c.
`A further embodiment of the present invention is shown
`in FIG. 9 in which either or both smoke and a target gas can
`be detected. Following is a description of the operation of
`this embodiment shown.
`A convective flow (as represented by arrow 100) can be
`created by heating air adjacent to a heating element 102.
`such as a drop resistor, next to the exit 104 of a chimney-like
`passage 106. This creates a convective flow within the
`enclosure and smoke or gas is drawn into the enclosure 107
`via entrance 108. Diffusion of gas and smoke within the
`enclosure 107 allows for their detection by two different
`means as described below.
`At least one target gas is detected by optical means using
`a beam of light 110 generated by light emitting means 112,
`such as a light emitting diode. The beam of light is directed
`across the detection chamber by lens 114 and is reflected by
`reflective means 116 through an optical gas sensitive sensor
`118 of the sort previously described. The attenuated light is
`then detected by light detecting means 120, such as a
`photodiode which is part of the gas detection system.
`Changes in the optical characteristics of the sensor 118
`caused by the presence of the target gas are thus detected and
`if a hazardous condition exists a response is made by the
`system such as an alarm being sounded or other suitable
`response action, such as the closing of a safety shutoff valve.
`The presence of smoke within the enclosure 107. and thus
`in the outside ambient air, is determined by reflection of light
`by smoke particles. As the beam of light 110 generated by
`the light emitting means 112 and lens 114 crosses the interior
`of the enclosure, the presence or absence of smoke is
`determined by photodiode 122 based on the amount of light
`reflected 124 by any smoke particles 126 that may or may
`not be present. In the absence of smoke. very little if any
`reflected light 124 will be reflected into photodiode 122.
`However when smoke is present, a finite amount of the light
`beam 110 will be reflected by the smoke particles 126 and
`thus detected by photodiode 122. The reflected light 124
`detected by the photodiode 122 is used to trigger an alarm
`for smoke that may be distinctive from the alarm for target
`gas. No sensor needs to be used or replaced in this detection
`mode. Hence the battery only key of FIG. 7.
`The present invention has been described in relation to
`limited examples which are for illustrative purposes and are
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`not intended to limit the scope of the invention. Although a
`number of specific embodiments and compositions have
`been described and illustrated herein, it will be apparent to
`those skilled in the art that further variations are possible.
`Thus, the present invention may be practiced otherwise than
`specifically described, and therefore is defined by the fol
`lowing claims.
`What is claimed is:
`1. A detection apparatus comprising:
`a first panel and a second panel spaced therefrom, said
`panels being of generally flat configuration;
`a sidewall being connected to and extending between said
`panels, the arrangement being such that said panels and
`said sidewall cooperate together to define therebetween
`an enclosure;
`said enclosure having an opening therein, said opening
`being of generally rectangular configuration;
`a door disposed adjacent to said opening, said door
`pivoting relative to said opening for selectively closing
`said opening;
`a detection system disposed within said enclosure;
`said detection system including:
`electronic components housed within said enclosure;
`a key having a generally rectangular configuration for
`the slidable insertion thereof within said enclosure
`through said rectangular opening;
`said key including:
`a power source; and
`at least one pair of electrical contacts electrically
`connected to said power source, the arrangement
`being such that when said key is fully inserted into
`said enclosure, said at least one pair of contacts are
`electrically connected to said electronic compo
`nents.
`35
`2. A detection apparatus as set forth in claim 1 wherein
`said door further includes:
`an outwardly curved flange extending from said door.
`the arrangement being such that said flange is promi
`nently displayed when said key has not been inserted
`into said enclosure.
`3. A detection apparatus as set forth in claim 2 wherein
`said door is spring biased to close said opening when said
`key is removed from said enclosure, the arrangement
`being such that upon removal of said key, said flange
`extending from said door pivots outwardly through said
`opening in order to visibly display the absence of said
`key.
`4. A detection apparatus as set forth in claim 1 further
`including:
`ejector means for partially ejecting said key from said
`enclosure.
`5. A detection apparatus as set forth in claim 4 wherein
`said ejector means for partially ejecting said key from said
`enclosure includes:
`an ejection means having a first and a second end, said
`ejection means being pivotally secured between said
`ends thereof to said first panel adjacent to said
`opening;
`an upright extending from said first end of said ejection
`means, said upright engaging said key on insertion of
`said key through said opening;
`an ejection button extending from said second end of
`said ejection means;
`a flange extending from said door for biasing said key
`towards said upright when said key is inserted
`through said opening;
`
`8
`compression means disposed within said enclosure for
`urging said key outwardly through said opening;
`a locking lip partially defining said opening for engag
`ing said key when said key is fully inserted into said
`enclosure, said locking lip, compression means,
`flange and upright interacting to secure said key
`within said enclosure with said contacts providing an
`electrical connection between said power source and
`said electronic components, the arrangement being
`such that when said ejection button is depressed, said
`ejection means pivots and said upright urges said key
`towards said flange so that said key becomes disen
`gaged from said locking lip permitting said com
`pression means to partially eject said key through
`said opening,
`6. A detection apparatus as set forth in claim 1 wherein
`said detection system includes:
`a smoke detection system.
`7. A detection apparatus as set forth in claim 1 wherein
`said detection system includes:
`an optically based target gas detection system.
`8. A detection apparatus as set forth in claim 1 wherein
`said detection system includes:
`a combination smoke and an optically based target gas
`detection system.
`9. A detection apparatus as set forth in claim 1 wherein
`said key further includes:
`an outer surface defining a window;
`at least one optical target gas sensor disposed within
`said key, said sensor being optically connected to
`said window,
`10. A method of replacing a key which is a combination
`of a battery and a sensor of a target gas detection apparatus,
`said method comprising the steps of:
`partially ejecting a key from an enclosure defined by a
`first and second panel and a sidewall connecting and
`extending between the panels, the step of partially
`ejecting being accomplished with the aid of an ejection
`system;
`manually gripping one end of the key;
`slidably removing the key from the enclosure;
`manually gripping an end of a replacement key which
`includes a combination of a battery and gas sensor;
`slidably inserting the replacement key into the enclosure;
`and
`locking the replacement key within the enclosure such
`that the key is engaged within the enclosure and the
`battery is electrically connected to the detection sys
`ter.
`11. An enclosure for a detection system comprising:
`a generally flat first panel connected to a second panel by
`a sidewall thereby forming the enclosure;
`a generally rectangular opening in said enclosure in which
`a door is pivotally mounted;
`a generally rectangular key configured to be inserted into
`said generally rectangular opening comprising a power
`source and at least one pair of electrical pads on the
`surface of said key wherein upon full insertion of said
`