US2033466A

US2033466A - Selective smoke detector

Info

Publication number: US2033466A
Authority: US
Inventors: Jr Harry Campbell Grant
Original assignee: Walter Kidde and Co Inc
Current assignee: Kidde Inc
Priority date: 1931-11-11
Filing date: 1931-11-11
Publication date: 1936-03-10
Anticipated expiration: 1953-03-10
Also published as: GB409677A; GB399449A; GB409577A

Description

March 1o, 1936. i' H C, GRANT, JR 2,033,466

SELECTIVE SMOKE DETECTOR Filed Nov. ll, 1951 2 Sheets-Sheetl 1 VENTOR u? ff/' March l0, 1936. H.. c. GRANT, JR 2,033,466v

SELEGTIVE SMOKE DETECTOR Filed Nov. 1l, 1931 2 Sheets-Sheet 2 .l0 16 0 l f I 'l il l? :3%` 2.9

' J3 il c?! |i M A I I if? A i N U 36 42 fg 3y I Eff `lllllllll! )IIHIIII 4 INVENTOR Patented 1o, 193s PATENT OFFICE SELECTIVE SMOKE DETECTOR Harry ampbell Grant, Jr.,`New York, N. Y., as-

Nsignor to Walter Kiddo t Company, Inc., New- York, N. Y., a corporation oi' New York Application ummm 11, m1, ser-1.1 No. 514.339

1o claim. (ci. 117-311) v The present invention relates to mechanisms for detecting the presence and location of smoke and embodies, more specifically, an improved smokefdetecting mechanism wherein a single au- 5 tomatic smoke detector is provided to indicate the presence and location of smoke selectively in a plurality of separate compartments.

More particularly, the invention embodies a detecting mechanism of the above character wherein a substantially continuous flow of iluid 'from the respective sections and introduced into a suitable testing or detecting mechanism. Where systems of this character become complex, the appreciable intervalo! time between the initial ypresence of smoke in a compartment and its arrival at the detecting mechanism has been found to be highly objectionable even to the extent of rendering the. apparatus ineffective.

In order that a mechanism may be provided wherein the iluid extracted from the respective;

compartments travels continuously from all of such compartments, the presen-t invention has been designed and an object thereof is to provide a v single smoke detecting mechanism for one or more -protected areas, means being provided to afford an indication ofthe existence of smoke in such area or areas, the mere momentary pres- `40 ence of smokev initiating an indication which persists.

A'further object of the invention is to provide a detecting mechanism wherein the plurality of iluid streams from the protected areas ow continuously, a mechanism being provided to take samples of the iluid stream successively and actuate an indicating mechanism in the event that smoke particles exist therein. v

A further Vobject of the invention is to provide 50 lin combination with the last named mechanism,

a means for providing al persisting indication upon the momentary presence oi' smoke in the stream of one o! the fluid conductors from the l protected areas,

5d Further objects, not specifically enumerated above, will be apparent as the invention is described in greater detail in connection with the accompanying drawings, wherein:

Figure 1 is a view in elevation, partly broken away and in section, showing a detecting mechanism constructed in accordance with the' present invention.

Figure 2 is a view in section, taken on line 2-2 of Figure 1, and looking in the direction of the arrows, a portion of the housing being broken l0 away in4 the interest of clearness to show the manner in which iluid is directed to the indicating mechanism successivelyv from the respective protected areas.

Figure 3 is a view in section,.taken on line 3-'3 15 of Figure 1, and looking inthe direction of the arrows.

Figure 4 is a view in section, taken on line 4 4 oi Figure l, and looking in the direction of the arrows. 20

Figure 5 is a diagrammatic representation of an electrical system for actuating a suitable signalling mechanism upon the existence ofsmoke CTI in the detecting chamber.

Figure 6 is a view similar to Figure 1, showing 25 a modiiled form of detecting mechanism.

Figure 7 is a view similar to Figure 2, taken on line 1 1 of Figure, and looking in the direction of the arrows. i

Figure 8 is a diagrammatic representation sim- 30 ilar to Figure 5, showing va modied alarm circuit for use in connection with the construction shown in Figure 6.

Referring vto the above drawinga'particularly to Figures-l, 2, 3,4 and 5, a plurality of conduits 35 are shown at. I0, these conduits being spaced at equal radii and communicating with a detecting chamber II within housing I2. Figure 2 illustrates the manner in which the conduits are connected to the housing I2. An outlet pipe I3 40 is also connected to the housing and to a suction fan I4. Fluid is thus drawn through the conduits I0 and-chamber II and into the outlet pipe I3 by the fan Il.

A shaft is 1s joumned within the housing l2 4l and is rotated by lmeans of a motor I6 which is connected to the shaft I! through a clutch having a nxed plate I1 and a slidable plate I8. The slidable plate I8 is suitably keyed to the shaft I5 and held' normally in engagement with plate 5 I1 by means of a spring I0 which is seated against a collar 2li pinned to the shaft II. An arm 2i is pivoted at 22 and formed with a forked extremity 2l to engage a iiange 24, formed on plate I8 to deciuh the pistes n and n and tuus stop the roi tation of the shaft I5. An electro-magnet 25 actuatesi a plunger or amature 26 which is pivotally connected to the arm 2 I, thus affording an electrical means for actuating the clutch. After the plate I8 has disengaged the plate I1 it moves` into engagement with a stationary bracket 21 which has a friction plate 28 and thus continued rotation of the shaft I 5, after declutching, is prevented.

Upon the shaft I5 and within the housing I2, a rotating disc 29 is mounted, the disc being formed with a duct 30 which communicates with a conduit 3l for applying fluid to a detecting chamber 32. The disc 29 is formed with an offset housing 33 to cooperate with the ends of the conduits successively and thus eiectively connect the duct 30 therewith. As the disc rotates, therefore, the

'conduit 30 is brought into communication with the respective conduits and fluid from the latter directed into the detecting chamber 32. The housing I2 is formed with a window 34 and disc 29' is provided with a skirt 35 upon which suitable indicia may be inscribed in order that the device may indicate under which conduit the conduit 30 is positioned at a given instant.

The conduit I3 is provided with a branch 36 whichcommunicates with the' detecting chamber 32 and thus creates a vacuum therein todraw fluid from the conduit 3| through the chamber and to the fan I4. ,If desired, the fan may beprovided with an exhaust conduit 31 which discharges the fluid into a chamber 38 in which a light source 39 is mounted, an outlet 40 being provided therefrom. In this fashionthe light source 39 is effectively cooled by the fluid flow from the conduit 311.

`Within the detecting chamber 32, a photo-electric cell 4I is mounted, thiscell preferably being provided with a compartment 4I across which the rays of light from lamp 39 pass as indicatedin dot and dash lines in Figure 1. The light from lamp 39 may be' suitably focused by means of a lens 42 mounted in an aperture of one wall of the housing which forms the chamber 38. In this fashion, smoke particles within the chamber 32 increase the light intensity in front of the photoelectric cell by reflection and cause the same to be actuated.

The photo-electric cell 4I is ladapted to be connected across a resistance 43 and battery 44 by means of a switch 45. The voltage across resistance 43 is appliedA to the grid of a. three element thermionic tube 46, the plate circuit of which tube is shownat 41 and includes a relay 49. Inthe form shown, in Figure 5, relay 48 is provided with three

contacts

49, 50, and 5I', respectively. Contact 5I is adapted to close a stick .circuit 52 in cluding a. battery 53 whereby a momentary impulse 'sufficient to actuate the relay causes the same to be permanently. energized. The relay is deenergized by means of a manual switch 54 in the stick circuit 52.

A contact 50 is connected to a circuit 55 in which a bell or other suitable alarm or indicating device 56 is connected while contact 49 is connected in a circuit 51 in which the electro-magnet 25 is connected.

From the foregoing, it will beseen that when switch 45 is closed and the photo-electric cell is in a non-illuminated condition there is no passage of electrons through the cell and therefore an open gap in the circuit exists. The elements of the system are so related that the potential of the grid of the thermionic tube 46 is practically the same as that of the terminal of the photo-electric cell, the system then being in a non-indicating condition. When, however, smoke particles or other suspended matter in the-fluid stream reaches the detecting chamber and the light cast upon the cell increases, the resistance of the cell is decreased and current flows through the resistance 43. This causes a. corresponding change in the potential of the grid of the thermionic tube 46 and a flow of amplifying current in the plate circuit takes place to operate relay 48.

As described above, actuation of the relay causes the same to be connected in a closed circuit with battery 53 and thus'the contacts are held/closed, while the alarm 56 is sounded and the motor I6 declutched from shaft I5. By observing the position of the disc 29, as displayed through window 34, the location of the smoke may be determined and suitable action instituted.

In the construction shown in Figures 6, '7. and 8, the elements for effecting the detection of smoke particles or other suspended matter are identical to those described in the construction shown in Figure 1. The mechanism, however, for determining the location of the condition is slightly different and includes a visual detector comprising windows 58 in each of theconduits I0. The conduits are formed with light tube extensions 59 having apertures 60 within which light from a light sourceA 6I is directed. Suitable reflecting means 60 may be provided in the ends of the tubes 59 to direct the light rays down the tubes and conduits I0 past the windows 58. In this fashion, existence of smoke particles in any vof the conduits I0 'gives rise to an illumination back of the corresponding windows 58, thus identifying' the exact location of the condition. The electrical circuit for operating the alarm mechanism of the construction shown in Figure 6 is illustrated by the diagram of Figure 8. In this circuit the elements are identical to those shown in Figure 5 except that the electro-magnet 25 and its corresponding circuit 51 is eliminated in as much as there is no declutching arrangement between the driving motor I6 and the rotating disc 29.

From the foregoing, it will be seen that a mechanism has been provided for detecting the existence of smoke or other similar conditions, by means of a single detector, the detector being of such construction that a persisting indication is given even if only a momentary condition exists in any of the protected areas. Means is thus provided for effecting a visual indication automatically, as well as effecting an indication upon even a momentary passage of foreign matter through a conduit.

The foregoing mechanism provides for a substantially continuous suction through all of the fluid stream conduits including the particular fluid stream conduit being supervised at any instant. In this fashion, the motion of the fluid through the conduits is substantially continuous and no delay is permitted in the movement of the fluid between the protected and the detecting device.

While the invention has been described with specific reference to the accompanying drawings, it is not to be limited, save as defined in the appended claims. v

I claim as my invention:

1. A device for detecting suspended matter in fluids comprising a plurality of fluid sources terminating in openings arranged in a circular path, means responsive to the presence of opaque suspended matter in fluids, a rotatable member formed with a conduit adapted to communicate with said openings to connect the responsive a,oss,4ss

sist rotation of the member upon passage oi suspended matter through the responsive means.

2. A device tor detecting suspended matter in fluids comprising a plurality of fluid sources terminating in openings arranged in a circular' path, means responsive tothe presence o! opaque l5 direct a iluid ilow. from the sources substantialsuspended matter in iluids, a rotatable member formed with. a conduit adapted to communicate with said openings to connect the responsive means with the sources successively, means to ly continuously, means to rotate the member, a clutch between the member and the rotating means, and means responsive to actuation of the responsive means to disengage the clutch upon passage of suspended matter through the responsive means.

.3. A device for detecting suspended matter in fluids comprising a plurality of iluid sources terminating in openings arranged in a circular path,

235 means responsive tothe presence o! opaque suspended matter in fluids, a rotatable member formed with a conduit adapted to communicate with said openings to-connect the responsive means with the sources successively. means to 3th direct a fluid tlow fromthe sources substantially continuously, means to rotate the member, a clutch between the member and the rotating means. and means responsive to actuation of the responsive means to.' actuate the clutch and apply a restraining force to the member to resist '5 means with the sources successively, means to rotation thereof upon passage of suspended mat.- ter through the responsive means.

4. A device for detecting suspended matter in iluids comprisinga plurality o! fluid sources terminating in openings arranged in a circular path, means responsive to the presence of opaque suspended matter in iluids, a rotatable member formed with a conduit adapted to communicate with said openings to connect the responsive direct a iluid ilow from the sources substantially continuously. means to rotate the member, a clutch between the member and the rotating means, means responsive to actuation oi the responsive means to actuate the clutch, yand indicating means rotatable with the member to indicate the connection established between the responsive means and the sources upon passage of suspended matter through the responsive means.

5. A devicefor detecting suspended matter in iluids comprising a plurality oi.' fluid sources terminating in openings arranged in a circular path. means responsive to the presence of opaque sus- O pended matter in fluids, a rotatable member formed with a conduit adapted to communicate with said openings to connect the responsive means with the sources successively, means to4 direct a iluid flow from the sources substantially c5 continuously, means to rotate the member, a

J the clutch in the said actuated condition upon passage oi' suspended matter through the responsive means.

6. A device tor detecting suspended matter in iluids comprising a plurality of iluid sources, means responsive to the presence of opaque suspended matter in fluids, means to connect the responsive means successively to the sources .to

shunt the iluid tlow from the sources successively throughn the responsive means. the responsive means being relatively near the last named con necting means, means to maintain a uid ilow from the sources substantially continuously, and means to permit visual inspection of the fluid from the respective sources.

7. A device for detecting suspended matter in iluids comprising a pluralityoi.' iluid sources,

means responsive to the presence of suspended opaque matter in fluids, a rotatable member to effect connection of the responsive means with the sources successively, means to direct a rluid ilow from the sources substantially continuous1y,-

means to rotate the member, a clutch-like member between the rotatable member and the rotating means, and means responsive to the actuation of the responsive means to disengage the clutchlike member 4upon passage ot suspended matter through the responsive means.

8. A device for detecting suspended matter in fluids comprising a plurality of iluid sources. means responsive to the presence oi.' suspended opaque matter in fluids, a rotatable member to effect connection 'of the responsive means with the sources successively, means to direct a il'uid ilow from the sources substantially continuously,.

means to rotate the member. a clutch-like member between the rotatable member and the rotating means, means responsive to actuation of the responsive means to actuate the clutch-like member, upon passage of suspended matter through v the responsive means and indicating means rotatable with the rotatable member to indicate the connection established between the responsive means and the sources.

9. A device for detecting suspended matter in iluids comprising a plurality of lluid sources, means responsive to the presence of suspended opaque matter in fluids, a rotatable member to eilect connection of the responsiver means with the sources successively, means to direct a fluid ow from the sources substantially continuously, means to rotate the member, a clutch-like member between the rotatable member and the rotating means, means responsive to actuation of the responsive means to actuate the clutch-like member, and means actuated by the responsive means to maintain the clutch-like member in the said actuated condition upon passage of suspended matter through the responsive means.

l0. A device for detecting suspended matter in fluids comprising a plurality of fluid sources, means responsive to the presence of suspended opaque matter in iluids, a-rotatable member to eilect connection of the responsive means with the sources successively, means to direct a iluid ilow from the sources substantially continuously, means to rotate the member, and means actuated by the responsive means to resist rotation oi.' the member upon passage of suspended matter through the responsive means.

HARRY CAMIBELL GRANT, Ja.

CERTIFICATE OF CORRECTION.

Patent No. 2,033,466. March 1o, 1956.

HARRY CAMPBELL GRANT, JR.

It is hereby certified that error appears in the above numbered patent requiring correction as follows: In the grant, name of the patentee, for "Henry Campbell Grant, Jr." read Harry Campbell Grant, Jr.; page 2, second column, line 62, after the word "protected" insert areas; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.v

Signed and sealed this 14th day of April, A. D. 1936.

Leslie Frazer (Seal) Acting Commissioner of Patents,