U.S. patent number 3,908,309 [Application Number 05/404,311] was granted by the patent office on 1975-09-30 for particulate products of combustion detector for closure frame.
This patent grant is currently assigned to Rixson-Firemark, Inc.. Invention is credited to Gordon L. Coulter, Duane D. Pearsall.
United States Patent |
3,908,309 |
Coulter , et al. |
* September 30, 1975 |
Particulate products of combustion detector for closure frame
Abstract
A door frame having a head member defining the top of a door
opening with the head member optionally supporting an electrically
actuated door holder-closer. A module having a frame shell section
and a detector for the particulate products of combustion supported
on the interior of the frame shell section with access openings
being formed in the shell section to enable particulate products of
combustion to pass through the shell to the detector. A socket
formed in the head member receives the module so that any
particulate products of combustion flowing through the door opening
pass through the module access openings to actuate the detector.
The detector is electrically connected to the door holder-closer to
effect closing of an otherwise open door in response to the
detection of the products of combustion. The detector may be either
an ionization or photocell type detector.
Inventors: |
Coulter; Gordon L. (Arlington
Heights, IL), Pearsall; Duane D. (Morrison, CO) |
Assignee: |
Rixson-Firemark, Inc. (Franklin
Park, IL)
|
[*] Notice: |
The portion of the term of this patent
subsequent to December 11, 1990 has been disclaimed. |
Family
ID: |
26910776 |
Appl.
No.: |
05/404,311 |
Filed: |
October 9, 1973 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
216202 |
Jan 7, 1972 |
3777423 |
|
|
|
Current U.S.
Class: |
49/31; 49/2;
49/504; 340/628; 340/630 |
Current CPC
Class: |
E05F
3/222 (20130101); A62C 2/12 (20130101); E05F
1/006 (20130101); E05Y 2201/482 (20130101); E05F
15/72 (20150115); E05Y 2201/462 (20130101); E05F
2003/228 (20130101); E05Y 2900/132 (20130101); E05Y
2201/474 (20130101) |
Current International
Class: |
E05F
3/00 (20060101); A62C 2/00 (20060101); A62C
2/12 (20060101); E05F 3/22 (20060101); E05F
1/00 (20060101); E05F 15/20 (20060101); E05F
015/20 () |
Field of
Search: |
;49/1,2,31,379,501,504
;52/1,221 ;16/48.5 ;160/1 ;250/381 ;340/237S |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Downey; Kenneth
Parent Case Text
RELATED APPLICATIONS
This application is related to applicants' copending applications
Ser. No. 216,202, filed Jan. 7, 1972 now U.S. Pat. No. 3,777,423
and Ser. No. 368,827, filed June 11, 1973, both for Condition
Responsive Door Holder-Closer.
This application is a also a continuation-in-part of U.S. Pat. No.
3,777,423.
Claims
What is claimed is:
1. In a closure frame having a head member defining the top of a
closure opening with the head member supporting an electrically
actuated closure holder-closer, the improvement comprising a module
including a frame shell section providing a module base and a
detector for the particulate products of combustion supported on
the interior of the frame shell section with access openings being
formed in the shell section to enable particulate products of
combustion to pass through the shell to the detector, a socket
formed in the head member to receive the module whereby particulate
products of combustion passing through the closure opening pass
through the module access openings to actuate thereby the detector,
and means electrically connecting the detector to the closure
holder-closer to effect closing of an otherwise open closure in
response to the actuation of the detector upon the detection of the
products of combustion.
2. In a door frame having a head member defining the top of a door
opening with the head member supporting an electrically actuated
door holder, the improvement comprising a module including a frame
shell section providing a module base and a detector for the
particulate products of combustion supported on the interior of the
frame shell section with access openings being formed in the shell
section to enable particulate products of combustion to pass
through the shell to the detector, a socket formed in the head
member to receive the module whereby particulate products of
combustion passing through the door opening pass through the module
access openings to actuate thereby the detector, and means
electrically connecting the detector to the door holder to permit
release of an otherwise open door in response to the actuation of
the detector upon the detection of the products of combustion.
3. The combination of claim 2 in which the frame shell section has
a contour substantially identical to that portion of the head
member adjacent to socket whereby the head member has a
substantially continuous surface contour.
4. The combination of claim 3 in which the head member includes a
horizontal jamb section, a casing or face section and a closure
stop section.
5. The combination of claim 4 in which the access openings are
formed in the frame shell section corresponding to the stop of the
head member.
6. The combination of claim 4 in which the access openings are
formed in the frame shell section corresponding to the horizontal
jamb section.
7. The combination of claim 4 in which the access openings are
formed in the frame shell section corresponding to the casing or
face element.
8. The combination of claim 4 in which the access openings are
formed in at least two of the frame member sections.
9. The combination of claim 4 in which the detector is an
ionization detector.
10. In a closure frame having a head member defining the top of a
closure opening, the improvement comprising a module including a
frame shell section providing a module base and a particulate
products of combustion detector in which detector an electrical
current characteristic is altered in response to the detection of
such particulate products of combustion, the detector being
supported within the interior of the frame shell section with
access openings being formed in the shell section to enable
particulate products of combustion to pass through the shell to the
detector, and a socket formed in the head member to receive the
module whereby particulate products of combustion passing through
the closure opening pass through the module access openings to
actuate thereby the detector.
Description
BACKGROUND OF THE INVENTION
The prior art is prolific in door holder-closer structures
responsive to the products of combustion to effect an alarm or
emergency release of open doors. Where such doors are released by
detectors, several approaches have been employed, generally ranging
from door release by a complex central fire alarm system
characterized by detectors spaced throughout a structure under
surveillance to a simple form of a fusible element mounted on the
arm of a door closer.
The most common type of quick response detector employed has been a
photocell (refraction type) detector or an ionization detector
mounted on the ceiling of a corridor, approximately five feet from
a fire resistant door to effect a barrier which will prevent
passage of the products of combustion from one section of a
building to another. As a general rule, if the top of the door, or
lintel, extends below the corridor ceiling over eighteen inches, it
is standard practice to install a second detector on the opposite
side of the door, again approximately 5 feet from the door. The
corridor closure may be a single door or a dual door using an
electromagnetic door holder-closer on each door. In any event, each
detector is located remotely from the controlled holder-closer.
Accordingly, at least two units must be separately mounted with
interconnecting wiring.
In the event products of combustion are generated, a detector
located on the ceiling causes the release of all controlled doors
to close the corridors. At this stage, personnel evacuation of a
building is possible since the doors will open in the direction of
egress from the building. However, in many cases premature and
unsafe door closing is effected because the detection of ceiling
smoke will occur well before the exitways through the doors become
smoke laden. Accordingly, the doors must be manually reopened to
permit evacuation of those persons who may have delayed their
exit.
Examples of prior art patents relating to condition detectors and
also detector responsive doors are as follows: US PATENT FILED
INVENTOR TITLE
__________________________________________________________________________
1,392,002 6-21-19 Engle Thermo Control for Fire Doors 2,665,129
1-5-54 Durbin et al Thermoelectric Door Operating Mechanism
3,009,138 11-14-61 Lindsay Radioactive Burglar Alarm System
3,039,764 6-19-62 Heinsman et al Electric Door Operator 3,069,997
12-25-62 Julian Apparatus for Preventing Ex- filtration of
Amoke-Laden Air from Smokehouse Enclosures 3,207,273 9-21-65 Jurin
Closure release Device 3,382,762 3-9-61 Basel et al Smoke Detecting
Device 3,430,220 2-25-69 Deuth Fire Detector 3,445,669 5-20-69
Jordan et al Radiation Sensitive Carbon Monoxide Detector 3,447,152
5-27-69 Jensen Fire and Smoke Alarm Device 3,495,353 2-17-70
Forsberg Door Operating Mechanism 3,496,381 2-17-70 Wisnia
Proximity Control Guard Plate 3,497,995 3-3-70 Forsberg Height
Sensitive Proximity Door Operator System 3,500,368 3-10-70 Magoa
Abe Automatic Ionic Fire Alarm System 3,534,499 10-20-70 Chaffee
Door Opening Apparatus
__________________________________________________________________________
Applicants' related applications above noted describe door
holder-closer structures each incorporating a particulate products
of combustion detector as an integral part of the holder-closer
structure and within the same housing.
SUMMARY OF THE INVENTION
The invention herein described incorporates a particulate products
of combustion detector module located in the door frame. The module
is preferably located above the door opening in a socket recess
formed in the frame head member. Any products of combustion pass
through multiple passageways located within the module to actuate
the detector. Location of the detector at this point and within the
door effects a major safety advantage. Instead of each controlled
door closing at the first evidence of smoke at the ceiling (and the
ceiling may be from seven to fourteen feet high), each door will
now remain open until the smoke "level" builds downwardly from the
ceiling to the height of the door -- leaving the doors open for
persons to move in either direction -- until such time as smoke or
products of combustion begin to block the actual exitway.
It is impossible to predict the logic of most persons under a fire
or panic condition. Faced with closed doors, many persons will
panic even though the doors will manually open with a normal force.
Moreover, early door closing is highly disadvantageous for those
buildings within which non-ambulatory patients are housed.
The location of the detector near the center of the door opening
or, in the case of a double door closure, near the center of the
corridor, is an advantageous location to detect smoke or products
of combustion. This detector location is effectively attained by
this invention because the detector module is preferably centrally
located on the head member. There is a natural flow of air or draft
through a door opening. This flow will carry the products of
combustion through this opening and also effectively through the
detector fluid flow passageways formed in the detector module of
this invention. The detectors, however, is not actuated until the
exitway is subject to smoke passage; thus, facilitating evacuation
until the last possible safe moment.
Additionally, the present invention has the economic advantage that
regardless of the height of the corridor ceiling relative to the
height of the door, one detector is all that is required to
properly monitor the door. The interconnection of separated ceiling
detectors and controlled frame mounted holder-closer is
eliminated.
From an esthetic aspect, the detector module is formed with the
same surface contour as the adjacent head member and without any
substantial projection of elements. Accordingly, a pleasing and
simple uncluttered appearance results at the door frame.
Moreover, inasmuch as the detector module does not project from the
door frame, the incidence of malfunctioning due to vandalism may be
substantially reduced.
DETAILED DESCRIPTION OF THE DRAWINGS
In order that all of the structural features for attaining the
objects of this invention may be readily understood, reference is
herein made to the drawings, wherein:
FIG. 1 is a view showing the application of a first embodiment of
the door frame detector module of this invention to a single door
controlled by a surface mounted door holder-closer;
FIG. 2 is a view showing the application of the detector module of
FIG. 1 in a double door corridor frame;
FIG. 3 is an exploded view showing the detector module of FIG. 1
removed from the associated header frame portion;
FIG. 4 is a bottom view of the detector module showing the bottom
row of module openings with the ionization chamber and its shield
being shown in broken outline;
FIG. 5 is a side elevation of the structure of FIG. 4 showing the
two side rows of module openings with the ionization chamber shield
being shown in broken outline;
FIG. 6 is a section view, taken along line 6--6 of FIG. 5, which
shows an internal top view of the detector module;
FIG. 7 is a section view taken along line 7--7 of FIG. 6, which
shows an internal side elevation view of the detector module;
FIG. 8 is a section view, taken along line 8--8 of FIG. 7, which
shows details of the ionization chamber, its protective screen, and
also the static shield;
FIG. 9 is a side elevation view of the ionization chamber and its
shield;
FIG. 10 is a schematic circuit which shows the failsafe connection
of the ionization chamber module to its associated circuitry, with
the principal components of a door holder-closer being
diagrammatically shown;
FIG. 11 is a view corresponding generally to that of FIG. 2, but
with a second or modified disposition of module openings;
FIG. 12 is a view showing a third disposition of module
openings;
FIG. 13 is a view showing a fourth disposition of module
openings;
FIG. 14 is a view corresponding generally to that of FIG. 1, but
with a photocell detector substituted for an ionization
chamber;
FIG. 15 is an exploded view showing the detector module of FIG. 14
removed from the associated header frame portion;
FIG. 16 is an elevation view of the interior of the photocell
detector module;
FIG. 17 is a plan view of the photocell detector module;
FIG. 18 is a section view taken along line 18--18 of FIG. 17;
FIG. 19 is a detailed view showing the two source light paths taken
in the photocell detector; and
FIG. 20 is a schematic circuit, corresponding generally to that of
FIG. 10, but modified to show the photocell detector.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, the products of combustion detector and
control of this invention is shown applied to a door frame which
outlines a single door opening. This door is controlled by an
electromechanically operated door holder-closer of the type shown
in Gaysowski U.S. Pat. No. 3,648,326 and also in Crane et al U.S.
Pat. No. 3,729,771. In particular, door frame 1, which is
preferably fabricated from metallic rail sections, is formed with a
socket which receives door frame detector module 2. Door
holder-closer 3 is surface mounted on the head member of frame 1.
The door holder-closer 3 includes a track 4 within which a slide
block (not shown) reciprocates. The left end of standard arm 5 is
coupled to the slide block. The right end of arm 5 is coupled to
the projecting end of a rotating drive spindle 6 which is an
integral part of the holder-closer mechanism and which extends from
the housing.
As is described in the aforementioned Gaysowski and Crane et al
patents, door holder-closer 3 includes as principal components a
coil spring, a link chain, a dashpot and an electromagnetic lever
assembly. This structure when coupled to door 7, as is shown in
FIG. 1, and also when electrically connected to a particulate
products of combustion detector, is capable of holding a door open
to a desired position. In response to the detection of smoke or
other particulate products of combustion, the electromagnetic lever
assembly is actuated to enable the coil spring to close the door.
This door control action isolates smoke and fire to a given room or
area and thus enhances fire safety.
Door 7 is preferably a metallic door which may be supported by a
plurality of butt hinges 8 (only one of which is shown) upon door
frame 1.
As is described in applicants' copending U.S. Pat. applications
Ser. No. 216,202 and Ser. No. 368,827, the head portion of a door
is an ideal location for a products of combustion detector. The
location of a detector at this area enables a fire detection system
to respond to smoke and other products of combustion sources
located on either or both sides of the door opening and to hold the
door open until such time as the smoke passes from one side of the
door frame to the other side. This is an ideal mode of operation
from a safety aspect.
The head member of frame 1 receives detector module 2 which is
formed and designed as an insert for a socket or opening formed in
the head member. Thus, a generally continuous contour is formed at
the head member, and the products of combustion detector does not
create an unsightly appearance. Additionally, the vandalism to
which projecting members may be subjected is minimized by making
detector module 2 appear as an integral part of the door frame. The
contour of module 2 is substantially identical to that of the
adjacent portions of the head member of frame 1.
Module 2 contains a particulate products of combustion detector,
such as an ionization detector or a photocell detector, as a
principal internal element. The shell of the module, as will be
hereafter outlined in detail, is formed with a plurality of access
openings so that the products of combustion can pass into and out
of the module and thereby actuate the detector.
FIG. 2 shows the application of a single door frame detector module
2 to control a pair of corridor doors 7 and 7'. Each door 7, 7' is
controlled by a door holder-closer 3, 3', respectively. In the
structural arrangement of FIG. 2, the detection of the particulate
products of combustion by detector module 2 actuates closers 3, 3'
so that both doors 7, 7' can be appropriately closed to isolate the
double door corridor. As is hereafter outlined, the electrical
circuitry of closers 3 and 3' are interconnected so that if
detector module 2 detects the particulate products of combustion,
both closers are activated simultaneously so as to close doors 7,
7' in response to such detection. It is unnecessary in the
application of a pair of doors which close off a hall or corridor
to employ individual detectors for each of closers 3, 3' inasmuch
as a single detector module is capable of adequately monitoring the
relatively wider head member of the closure frame.
FIG. 3 shows detector module 2 removed from head member 9 of frame
1. Head member 9 is one of the many metallic channel constructions
commonplace in the steel door frame art. In general, such frame
channels are preferably fabricated of metal where integrity to fire
is a prime consideration. Head member 9 includes vertically
disposed casing or face trim sections 10, 10', horizontally
disposed jamb sections 11, 11' and a door stop section 12. In a
particular building installation, the channel may or may not be
filled with adjacent structural material such as concrete or
building mortar.
A portion of the channel of head member 9 is removed to form a
socket or opening 13 which is to receive module 2. Module 2
includes as its principal components a metallic frame shell 14
which supports a products of combustion detector 15 as hereinafter
set forth in detail. Frame shell 14 is contoured or formed in a
manner corresponding to the adjacent contours of head member 9;
thus, the shell includes a facing section 16, a jamb section 17, a
vertical stop section 18, and a horizontal stop section 19. Four
mounting brackets 20 supported by head member 9 project into socket
13. When module 2 is elevated into socket 13 and screws 21 are
affixed, the module is held rigidly in place within head member 9.
Accordingly, the head member presents a generally uniform contour
to the viewer without any substantial projections which would
detract from the door frame decor.
Module stop sections 18, 19 are formed with a plurality of access
openings 22, 23, respectively. Access openings 22, 23 permit the
products of combustion to pass into the interior of the module so
that these products may actuate the products of combustion detector
15 to appropriately operate door holder-closer 3 (FIG. 1).
The particular detector 15 shown in FIG. 3 is an ionization type
detector and this detector employs as its principal components a
U-shaped electrostatic shield 24 which is formed with appropriate
passageways so that products of combustion entering the shield may
also find their way into the interior of an ionization chamber 25,
shown in broken outline in FIG. 4. Fluid flow access (i.e.,
particulate products of combustion) may be into either of access
openings 22 or 23, depending on the particular location of the
products of combustion source relative the door frame. In any
event, a flow into and out of the detector module by way of the
ionization chamber is provided so that early detection can be
attained.
FIG. 5 shows electrostatic shield 24 in broken line side elevation.
The disposition of access openings 22 and 23 relative U-shaped
shield 24 shows that fluid flow from one set of access openings to
the other must necessarily flow through electrostatic shield 24 of
the ionization detector 15.
Connector 26 (FIG. 3) and its associated electrical conductors
located within the channel of head member 9 interconnect detector
module 2 and holder-closer 3 and also the line source. The use of a
connector enables module 2 to be removed readily from head member 9
so that necessary inspection, repair and replacement of the module
can be easily made.
FIGS. 6 through 9 (FIG. 9 on sheet 4) show the principal components
which comprise ionization detector 15. These components are housed
within and supported on frame shell 14 of detector module 2.
Metallic electrostatic shield 24 which is of a U-shaped metallic
construction is located within the stop sections 18, 19 of the
shell. In particular, the electrostatic shield comprises spaced
plates 27 and 28 integrally connected one to the other by means of
curved top 29. As is shown in FIGS. 6, 7 and 9, top 29 is slotted
so that vertically projecting tabs 30, 31 emanate therefrom. A long
screw 32 passes through apertures formed in tabs 30, 31 so that
electrostatic shield 24 is supported by this screw on support bar
33. Spacer bushing 34 extends between tabs 30, 31 and spacer
bushing 35 extends between tab 31 and support bar 33. Screw 32
passes through bushings 34 and 35.
Ionization chamber support plate 36 is also fixed to support bar
33. Additionally, side plates 37 and 38 extend perpendicularly
relative bar 33 and support plate 36. Plates 37 and 38 are spaced
so that electrostatic shield 24 and its spaced leglike plates 27,
28 are fixed tightly therebetween. Side plate 38 is formed with a
plurality of access openings which are in alignment with stop
access openings 22 (FIG. 7). Accordingly, products of combustion
entering stop access openings 22, 23 pass between spaced plates 27,
28 of electrostatic shield 24.
Ionization chamber cup 40 extends and is sandwiched between plates
28 and 36 (FIG. 8). Plate 28 is formed with a circular hole 41
(FIGS. 7, 8) which mates with the opening of cup 40. Cup 40 defines
ion chamber 25. Cup 40 is generally formed with a cylindrical side
wall which is closed at its right end (FIG. 8) by a metallic bottom
43. Radioactive source 44 is supported on the left end of metallic
positive electrode post 45 so that the source is centrally located
within the ion chamber. Insulator bushing 46 isolates electrode 45
from metallic support plate 36. In a preferred commercial
embodiment, radioactive source 44 is a sandwich comprising a silver
layer 44a, a gold layer 44b containing dispersed Americium oxide
and a gold sealing layer 44c.
The passing of the particulate products of combustion through the
space defined by plates 27, 28 of electrostatic shield 24 through
opening 41 into ion chamber 42 affects the electrical conductivity
between radioactive source 44 and ion chamber cup 40 so that the
appropriate amplifier circuitry can detect such products due to the
change in electrical current flow in the ion chamber.
In view of the fact that small particles other than those created
by the products of combustion, such as insects, can also create a
current flow change within ion chamber 25 which simulates smoke or
fire, screen 47 envelops the outside surface of cup 40. This screen
also extends between shield plates 27 and 28. Accordingly, all
fluid flow into ion chamber 25 must pass through the cylindrical
wall of the screen 47. Thus, foreign particles such as insects
cannot enter into ion chamber 25.
Additionally, the screen prevents radioactive source 44 from
falling from detector module 2 in the event that the source support
on post 45 is broken. This is a desirable and necessary safety
measure.
The right end of positive electrode 45 (FIG. 8) and associated
electrical preamplifier components are shielded within metallic
housing 48 supported on the right surface of metallic support plate
36. Additional electrical circuit components generally denominated
as 49 are supported on insulator circuit board 50. Insulator
circuit board 50 also supports a male socket connector 51 which
mates with the electrical connector 26 (FIG. 3) so that the
detector module can be connected to external circuitry. Circuit
board 50 and its supported components are carried by shell jamb
section 17. In view of the fact that the shell is metallic,
insulator 52 is sandwiched between elements 17 and 50 to provide
the necessary electrical isolation.
Shell face section 16 supports reset pushbutton switch 53 and pilot
light 54 (FIG. 6) so that these two components are exposed through
appropriately located openings positioned in frame shell 14. The
operation of components 53 and 54 is hereafter described with
respect to the schematic circuitry of FIG. 10.
FIGS. 11, 12 and 13 show alternative frame shell arrangements for
detector module 2. In particular in FIGS. 11 and 12, the frame
shells 14 have identical contours with that previously described
with reference to the FIGS. 3 and 4. However, in FIG. 11 access
holes 55 and 56 are located on shell face section 16 and shell jamb
section 17. With reference to FIG. 12, access holes 57 and 58 are
located on shell face section 16 and horizontal stop section 19.
These alternative hole dispositions of shell section 14 provide
different fluid flow characteristics which may be particularly
advantageous in securing proper fluid flow of particulate products
of combustion in certain locations. In FIG. 13 it should be noted
that the door should be located on the far side of the head member
9, so that fluid flow through access holes 57 and 58 will not
enable the particulate products of combustion to pass around a
closed door.
In FIG. 13 access holes 59 and 59' are located on the vertical
portions of stop 12. In this construction, particulate products of
combustion can not pass through a closed door in view of the fact
that access holes 59 and 59', depending upon which side of stop 12
the door is located, will be covered in response to door
closing.
The schematic circuit of FIG. 10 shows the electrical
interconnection of door frame detector module 2 to door
holder-closer 3. A preferred detailed circuit description for
module 2 is described in U.S. Pat. No. 3,673,586, issued to Lyman
C. Blackwell for Resistance Controlled Timed Pulse Generator.
In order that the electrical operation of the structure of FIG. 10
may be understood, it will be necessary to describe generally the
construction of door holder-closer 3. The closer comprises as its
principal components a helical spring 60 (FIG. 10) connected to a
dashpot rotor 61. Whenever door 7 (FIG. 1) is opened, standard arm
5 which is connected to dashpot rotor 61, rotates the rotor
responsively until roller 62 is engaged by armature latch 63. The
engagement of elements 62, 63 will be maintained in the event
electromagnet 64 is energized. In the event elements 62, 63 are
latched and electromagnet 64 is energized, as hereafter set forth
in response to the detection of the particulate products of
combustion by detector 15, electromagnet 64 will be deenergized. In
response to this deenergization, the latch of elements 62, 63 is
broken and the compression force of spring 60 causes a clockwise
rotation of the dashpot rotor 61. This rotation of the rotor causes
a movement of standard arm 5 which enables door 7 to close.
The schematic circuit of FIG. 10 shows an electrical circuit
effecting the interconnection of electromagnet 64 to ionization
chamber 25 to effect hold-open and closing of door 7 in a failsafe
manner of operation. Additionally, the schematic circuitry
incorporates a detector and amplifier unit within module 2 which is
failsafe in operation. In particular, if all of the components of
the module 2 are properly operating, door 7 will remain in
hold-open effected by the latching of roller 62 by armature 63 in
response to the manual closing of control switch 65. If, however,
module 2 is not properly operating or, alternatively, this unit
senses a condition such as smoke, door 7 will be released from a
latched hold-open position and closed in response to the closing
force exerted by coil spring 60.
The detailed operation of the circuitry of FIG. 17 is as
follows:
Assuming module 2 is in proper operating condition and that the
ionization chamber 25 input applied to terminals 66 and 67
indicates an absence of a smoke condition, door 7 will be held in
the open position in response to the manual closing of switch 65;
that is, the closing of switch 65 applies line voltage from
terminals 68 and 69 to amplifier A of module 2. The application of
line voltage to amplifier A energizes amplifier output relay 70,
thereby closing normally open contact 70a. The closing of contact
70a applies line voltage to the coil of power relay 71. With this
occurrence, normally open contact 71a is closed, thereby applying
line voltage to fullwave bridge rectifier 72 to energize
electromagnet 64 with a pulsating-direct-current voltage. The
energization of electromagnet 64 drives magnetic armature 63 into
locking engagement with roller 62. Thus, so long as electromagnet
64 is energized, door 7 will be held in an open position.
In the event, however, (a) a slight manual closing force is applied
to door 7, (b) switch 65 is opened, (c) module 2 malfunctions, or
(d) an undesired condition such as smoke is detected by chamber 25,
armature 63 will be pivoted from engagement with roller 62, and
spring 60 will close the door to the position shown in FIG. 1.
In the situation of case (a) above, the manual override closing
force causes armature 63 to release the latch formed with roller
62.
In situations (b), (c) and (d) above, electromagnet 64 is
deenergized, thereby enabling the camming action of roller 62 to
elevate armature 63.
In a multiple door installation, such as the corridor application
shown in FIG. 2, the electromagnet of holder-closer 3' is merely
interconnected with the circuitry for holder-closer 3 so that both
electromagnets (corresponding to electromagnet 64) are energized or
deenergized simultaneously.
Reset pushbutton switch 53 is connected to amplifier A of module 2
so that the circuitry can be again placed in a detection readiness
condition after the closer has released in response to a fire or
alarm condition. Switch 53 is accessible for manual operation from
the front of frame shell 14 (FIGS. 3 and 6).
Pilot light 54 is also connected to amplifier A of module 2. When
the circuitry is in a properly operating supervisory condition, the
pilot light will periodically emit light. When smoke is detected,
the pilot light will remain on. A deenergized pilot light indicates
an electrical malfunction. In a preferred circuit arrangement the
circuitry "locks" into an alarm condition (pilot light 54 on) and
remains in an alarm condition until the unit is reset by manual
operation of switch 53.
FIGS. 14 through 20 describe a second embodiment of this invention
in which a photocell detector 80 is employed in lieu of the
ionization detector 15 described with reference to the prior
Figures. The principal difference in the second embodiment is that
the ionization chamber has been replaced by a light tube which
senses the obscuration effect of the particulate products of
combustion in a path defined by a light source and a photocell
detector. Additionally, a compensating tube is employed to
compensate for variations which might occur in the light source due
to aging.
Referring to FIGS. 14 and 15, the module shell for the second
embodiment is essentially the same as that described with reference
to FIG. 2. In particular, the shell comprises sections 16, 17, 18
and 19.
The principal difference is that the access holes formed in
sections 18 and 19 for the embodiment of FIGS. 14 and 15 are
elongated slots which traverse a greater horizontal length. This
variation in access holes 81 and 82 is required in order to effect
optimum entry of the particulate products of combustion into the
photocell detector as hereafter described.
More particularly, these products must pass into elongated detector
tube 88 so that light emanating from source 83 (FIGS. 16, 19 and
20) may be absorbed or attenuated in its path of travel to
photocell 89. Detector tube 88 is formed by a plurality of spaced
support plates 90 which extend from the front to the rear of tube
88. The peripheral edges of support plate 90 carry blackened wire
screen 91 whose interstices permit the passage of smoke into the
interior chamber of detector tube 88. Each of the plates 90 is
formed with a central hole 92. Accordingly, light emanating from
source lamp 83 travels through light conduit elbow 93 (FIG. 20) in
a path of travel in which the light is reflected from mirror
surface 94 through lens 95 through the plurality of axially aligned
holes 92 to impinge upon photocell 89.
Light from source 83 also travels through a second path which
includes second light conduit elbow 96. Light traveling in this
conduit elbow is reflected by mirror 84 and follows a path through
lens 97 into closed standard tube 98 to thus impinge upon photocell
85. The interior chamber formed by standard tube 98 is hermetically
sealed and, accordingly, products of combustion cannot enter this
tube and, therefore, no light absorption occurs within this tube
during smoke entry into the inner confines of detector module
2.
Referring now to FIG. 20, photocells 89 and 85 are connected in a
bridge circuit with variable resistors 86 and 87. Output terminals
66 and 67 of the bridge circuit correspond to like numbered
terminals shown in the schematic circuit of FIG. 10. The only
circuit change is the substitution of the photocell particle
detector 80 for ionization particle detector 15. Circuit operation
is attained which is substantially identical to that previously
described with respect to FIG. 10. Variable resistors 86 and 87 are
normally adjusted so that with ambient (smoke absent) conditions no
signal appears at the output of amplifier A. However, in the event
smoke enters detector tube 88 through wire screen 91, the bridge
becomes unbalanced and a signal change appears at terminals 66 and
67. This signal change is applied to amplifier circuit A in
accordance with the operation previously described with reference
to FIG. 10, thus causing door holder-closer 3 to close door 7.
It should be understood that the above described embodiments are
merely illustrative and that changes can be made without departing
from the scope of the invention.
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