US1996308A - Fire alarm mechanism - Google Patents

Description

April 2, 1935. 1,996,308

R'. B. SHRYOCK FIRE ALARM MECHANISM Filed Aug. 11, 1953 3 Sheets-Sheet l April 42, 1935.

R. B. sHRYocK FIRE ALARM MECHANISM 3 sheets-sheet 2 Filed Aug. ll, 1933 linventol April 2, 1935.

R. B. sHRYocK 1,996,308

FIRE ALARM MECHANISM Filed Aug. 11, 1933 3 sheetssheet 3" Patented- Apr. 2, 1935 UNITED STATES PATENT OFFICE ma ALARM MECHAMSM Robert B. Shryook, Arlington; Tex. Application August 11, 1933, serial No.' 684,669

1 claim. (C1. 177-355) This invention relates to electric ilre alarm systems and to heat-actuated devices for the operation of automatic lire alarms of that class which may employ a plurality of such devices at various points throughout a building or the like, and one oi' my general objects is to produce a device o! this character which has a minimum number oi.' contact points to lessen the possibility of corrosion with the result that the alarm system might fail in time of need.

Another object oi' the invention is to provide a thermostatic device with no moving wires subject to abrasion and electrical shorting. and in which the thermostatic mechanism Ais not in electric circuit with any part of the system or mec A further object oi the invention is to provide a re alarm system with means for the preliminary sounding oi a local alarm when the heat reaches a predetermined point, and which, will sound a second alarm if the heat passes above the local alarm operation temperature.

A still further object ot the invention is to produce a double circuit alarm of the character mentioned which is provided with visual signalling or annunciating mechanism to locate the particular protective device which has caused the sounding of the local alarm, and a device which eect a distant alarm which a temporary suspension of the current flow in the power line of the signal circuit will not turn in a false alarm on the telephone or external alarm circuit.

With the general objects named in view and others as will hereinafter appear, the invention consists in certain novel and useful features oi' construction and combinations of parts as here-l inafter described; and in order that it may be fully understood, reference is to be had to the accompanying drawings, in which:-

Figure l is a plan view of a unit of the electrical re alarm system embodying the invention, the cover of the unit being omitted.

Figure 2 is asection of the unit, including the cover, on the line II-II of Figure l.

Figure 3 is an inverted plan view of the unit.

Figure 4 is a section on the line IV-IV of Figure 1.

Figure 5 is a detail perspective view of the thermostatic unit.

Figure 6 is a detailperspective view of a terminal support of the unit.

Figure 7 is a diagrammatic view of the preferred alarm system as including two units connected in series.

Figure 8 is a diagrammatic view of a modified alarm circuit system.

In the said drawings, where like reference characters identify corresponding parts in all oi' the gures, the heat-actuated device is here shown as in the form of a coiled thermostat element i, which has one oi' its ends clamped by a plate 2 to an upstanding leg 3 formed on a plate 4. The plate 4 is 4swivelled as at 5 on a base or support plate 6, having a cavity or space on its underside to house certain wiring hereinafter mentioned. The plate 6 forms the base of the protective device and may be secured to a wall, placed on a shelf, or otherwise located at the erating ear or handle l by means of which the plate may be adjusted to the position desired as indicated by point 8 on the plate in cooperative relation with a series of temperature indicating marks 9 on the base t. After the plate and consequently the thermostat, has been adjusted, it is locked by a clamp bolt i@ carried by the base t and projecting through an arcuate slot ii in the plate d.

Secured to or projecting from the base t is a xed ear l2, to the upper end of which and insulated therefrom, are three spring conducting ngers or arms, it, l@ and lli.

Also secured'to or projecting from the base t is a second fixed ear or arm It, as illustrated, having slots 'its receiving clamping bolts so that the arm is adjustable on the base. Secured to the upper end of the arm and insulated therefrom are a pair of terminal members il and it, the former, for contact with the spring nger it, and the latter, for cooperation with the iinger I5 as will hereinafter appear. In the construction here illustrated the terminal Il is adjustable on the base 5 as explained, and the terminal I8 is provided with a compensating adjustable bolt contact I9 against which the nger I5 is normally in contact, the adjustment being provided to vary the time of a secondary alarm signal and to compensate for the setting of the terminal i1 with respect to the operating tempera ture ofthe thermostat as will hereinafter more particularly appear.

The third spring finger It is also subject tc adjustment for time and to compensate for the setting of terminal Il, and is, therefore, normally in contact with an adjustable bolt 2E can'ied by an ear 2| projecting from the stand- 55 ard I6, and as this bolt and standard are not in electrical circuit it is unnecessary that they be insulated rom the base 6.

The base 6 is provided with the following electrical connections; 22 is a binding post electrically connected by a wire 23 fitted within the hollow underside of the base 9, to the nger I3; 265 is a binding post electrically connected by a wire 25 to the spring finger I5; 29 is a binding post electrically connected by a wire 21, to the spring finger I4; 28 is a binding post electrically connected by a wire 29, to vthe terminal I1; and 30 is a binding post electrically connected by a wire 3|, to the terminal I8.

The thermostatic element I has its free end terminating in a head 32, and when set in the manner above described, the spring finger i3 is in the path of movement of said head 32 as the thermostat expands and moves, due to a temperature rise. If the spring thermostat expands to a sufficient degree its head 32 will contact the nger I8 and will break the contact between said finger and its terminal I1. Said spring nger I3 is formed with a side ear 33 provided with a contact point 34 for cooperative engagement and circuit closing, through a similar contact 35 car-- ried by the finger I4. Therefore, concurrently with the break of the contact between finger I3 and terminal |1, or a little thereafter as determined by the setting of the adjusting device 20, provided the thermostat continues to expand, contact points 34 and 35 will come into abutment to close a circuit therethrough.

In addition to the contact 34, the spring nger I3 carries a projecting post member 36 in position for contact with an insulating block 36a on the third spring finger I5. Therefore, further continued movement of the thermostat l and spring nnger 18, the extent of movement required and consequently the temperature which must be reached, being determined by the setting of the adjusting device I9, will ultimately cause the post 36 to move the spring .finger I5 out of electrical connection with the terminal I8 through the bolt I8.

From the above, it will be evident that there is only one circuit established by the devices described, that made by contacts 34 and 35, while two circuits are broken by movement of such mechanism.

In Figure '1, the preferred method of connecting the devices is shown, a pair of the devices being indicated connected in series, although it is to be understood that any number may be employed each located at a point to be protected. In the drawings 15 and 16, respectively indicate the high and low voltage sides of a transformer, the former being connected to an electric light circuit or other source of power.

Extending from the low voltage winding of the transformer are a pair of power or lead wires 11 and 18. Connected to the wire 11 by a wire 19 are the binding posts 22 and 24 of the first protective device, the outlet binding posts 28 and 30, respectively, of said iirst protective device are connected by wires and 8| to the binding posts 22 and 24 of the second protective device, and so on, throughout the entire series of devices, which are located at various points.

The middle outlet binding posts 28 of the devices are respectively connected by wires 82 and 83 to individual annunciators 84 and 85, located at a convenient point to indicate which protective device is in operation. The opposite terminals of the annunicators are connected by wire 86 back to the line or power wire 18 to complete the circuit.

The binding post 23 of the last protective device cf a series is connected by a. wire 81 to one side of the coil of a relay 88, the other terminal of said coil being connected by wire 89 to the Wire '58 from the transformer. This relay is of that character where the relay circuit is held open as long as the relay coil is energized. The terminals of the relay circuit are respectively connected by wires 90 and 9|, to the power wire'11 and to a local alarm 92, the circuit being 'completed through wire 98 to the power wire 18. It will thus be evident that if current ceases to now in the relay coil, the alarm 92 will be sounded through the breaking of the circuit through finger I3 and its terminal i1.

The binding post 30 of the nal protective device of the series is connected by a wire 94 to one terminal of the coil of a relay 95, the other terminal of the coil having wire 96 leading to the power wire 18. This relay is also of the type where the now of current in the coil holds the relay circuit open. This relay is to operate any suitable outside alarm circuit, if the finger I5 breaks the circuit through its terminal I8. In the drawings, two types of external alarm circuits are shown, one being energized from the transformer coil 18, and the other having its own source of power supply. The latter, the self-energized circuit, comprises a wire 91 connected to a battery 98, which inturn is connected to any suitable type of alarm 99, the companion terminal of the alarm leading back through wire |00 to the other side of the relay. The other type of signal circuit constitutes wire |0| from one of the relay terminals, an alarm |02, a wire |03 to the line wire 18, and a line |04 from line wire 11, to the other terminal of the relay. Thus, upon the closing of these circuits, through the breaking of current flow through coil 95, the alarms 99 and |02 will both be operated.`

To avoid the sounding of false alarms should the electric light or other current supply con'- nected to winding 15, fail from any cause, the following stand-by power connections are provided: A wire |05 leads from the power wire 11 to one terminal of a relay coil |09, the other terminal being connected back to the power source, wire 18, by a wire |01. As long as current is flowing through the relay it is held aaginst closing of the relay circuit. Also connected to the wire 11 through wires |88 and |05 is a battery |09, the other side of the battery being connected by wire I I0 to one terminal of the relay. the companion relay terminal being connected by wire I I to the line wire 18. With these connections, it will be evident that if the electric light circuit fails from any cause, the stand-by circuit will immediately feed the protective devices from the battery |09, before the inertia of the various parts has an opportunity to effect completion of any of the alarm circuits, which, under the conditions mentioned, would otherwise cause the sounding of a false alarm.

Another method of connecting the devices is shown in Figure 8, where the electric light voltage may be employed for operation of the alarms. In said figure, where a pair of devices are also shown as being connected in series, it being understood that any number of devices may be used, 31 indicates a transformer connected to a power or line wire 38. One terminal 39 of the low voltage side of the transformer 31 is connected by a wire 40 to binding posts 22 and 24 of the first protective device, and the binding posts 28 and 38 of said device are respectively connected to bind- Cil ing posts 22 and 24 oi the second device, and so on througho'ut an entire series of any desired number, located at different points, Within a building or location in which warning of re is to be sounded or indicated.

The terminal 26 of each protective device is connected by an individual wire 4l to a predetermined annunciator or visual signal d2 and 43, for the first and second protective devices respectively herein illustrated. 'I'he opposite sides of the annunciator signals are connected by a common wire 44 to the other terminal 45 of the low side of the transformer.

The binding post 28 of the ilnal protective device in the series, is connected by a wire 46 to one side of the coil of a relay 4l of that type in which a current iiow prevents operation of the relay to close the second or relay circuit, and the other terminal of the said coil is connected by a wire 48 to the terminal 45 of the low side of the transformer.4 If desired, a pilot light 4S may be shunted across the coil of the relay to visually indicate that current is iiowing through the protective devices.

One terminal oi the open side of the relay 55 is connected by a wire 58 to one terminal of the coil of a third relay 59, While the other terminals of the two relays are connected by wires 60 and 6i to the power line. VThis third relay is of the type requiring that a current shall flow through it before it will'close or short its relay circuit, as represented by wires 62, for the operation of n. telephone line alarm, a distant siren, or other type of signal.

With the constructions described, it will be evident that upon expansion of the thermostat to break the circuit at I3 and I 1, relay 4l will be immediately aii'eoted and a circuit will close through the alarm 52, which may be a local alarm. Simultaneously or slightly after the alarm is sounded (depending on the setting of bolt I9),

contacts 3@ and 35 will close a circuit through 3 the annunciator of the particular protective device which is being subjected to heat.

If the temperature at the protective device continues to rise, further expansion of the thermostat will cause the spring linger I3 through its post 36 to strike the finger l5 and open the circuit between said finger and its terminal I8. This will cause the operation ofthe relay 55 to close a circuit through the third relay 58, which in turn will close a circuit through the external alarm vWires 62.

With the apparatus and wire systems shown. it is possible to wire any desired number of devices in series and have a constant check on the operativeness of the system, in the first circuit because of the auxiliary power source, and in the second by the pilot lights. From the above description it will be apparent that I have produced a system and apparatus which possesses all oi' the features of advantage set forth as desirable; and while I have described and illustrated what appears to be the preferred forms of the invention, I reserve the right to make all changes within the spirit oi' the invention and without the ambit of the prior art.

I claimz- In an electric fire alarm system, an electric current supply line, a pair of relays, a pair of conductors in circuit with the supply line and relays respectively, a third conductor, an annunciator in electrical connection with said third conductor and the supply line, a heat-responsive device for automatically breaking connection of one of said pair of conductors with the supply line and then establishing contact between said conductor and the third conductor to complete a circuit through the annunciator for then breaking the circuit through the second of said pair of conductors, and an alarm device in circuit with each of said relays to be successively actuated upon the breaking oi' the circuit through their respective relays.

' ROBERT B.. SHRYOCK.

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