US1015878A - Fire-alarm. - Google Patents

Fire-alarm. Download PDF

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US1015878A
US1015878A US58803010A US1910588030A US1015878A US 1015878 A US1015878 A US 1015878A US 58803010 A US58803010 A US 58803010A US 1910588030 A US1910588030 A US 1910588030A US 1015878 A US1015878 A US 1015878A
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wire
expansion
alarm mechanism
detent
trip
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John Enright
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    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B17/00Fire alarms; Alarms responsive to explosion
    • G08B17/02Mechanical actuation of the alarm, e.g. by the breaking of a wire

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  • WITNESSES NITED STATES PATENT OFFICE WITNESSES NITED STATES PATENT OFFICE.
  • This invention relates to fire alarms and especially to automatic re alarms.
  • the object of my invention is to produce an automatic heat detector and fire alarm, by means of which destructive fires in hotels, school houses, and other buildings including ⁇ the holds of vessels, may be detected before attaining dangerous headway, in order to quickly extinguish same. I accomplish this result by utilizing the expansion of a wire or rod, due to the rise in temperature, to release certain mechanism which detains an alarm.
  • FIG. 1 is a plan view of the detector and two alarm connections, parts broken away.
  • Fig. 2 is a section on the line 2*?. of Fig. 1.
  • Fig. 3 is a section on the line 3 3 of Fig. 1.
  • Fig. 4 is a plan view in detail of a modification.
  • Fig. 5 is a view similar to Fig. 2 of a modification, part broken away.
  • Fig. 6 is a perspective of a detail.
  • 5 indicates a bed plate composed of porcelain or other suitable material having a low coefcient of superficial expansion, which plate may be held in set position against a wall, ceiling, or other suitable location by bolts 6.
  • a spiral wire or coil 7 of suitable thickness and material, having a large coefficient of linear expansion.
  • the said spiral wire 7 passes snugly between a plurality of radial arranged rollers or guides 23 pivoted in housings 13, which have a comparative large co ⁇ efficient of expansion.
  • the screws 14 which secure the outer ends of the housings to plate 5 are rigid, while the screws 15 which connect the inner ends of the housings to plate 5 are loose in the slots 34 in the said plate. Housings 13 and rollers 23 preserve the shape and position of the spiral wire 7.
  • the inner end of the spiral wire or coil 7 Specification of Letters Patent.
  • a lever or rocker 8 is made fast to the plate 5 by screw 33 and clamp block 18, while the outer or free end of the said coil is secured to the upper arm 8 of a lever or rocker 8 near the fulcrumed point, by means of screw 2O and clamp block 19.
  • the lever 8 is pivoted to the plate 5 by a screw 21 and is spaced therefrom by block 22.
  • the lever or rocker 8 is in an approximate radial the spiral or coil 7.
  • the lever 8 carries an adjusting screw 9 at its outer end, having a projecting squared end 9.
  • the lower arm 8 has a recess 35 and an adjusting screw 16 passing into same from the opposite side of the said arm 8.
  • a spring 36 is secured to the end of the arm 8 having an outward tension, which provides a shoulder 36.
  • a set screw 9a holds the said spring to any desired adjustment.
  • the projection 9 and the shoulder 36 both have the same function as will be seen in the hereinafter description. Either form may be used as desired.
  • a trip l0 is pivoted adjacent the end of arm 8 at 11 and when the coil is in normal position the inner end or arm thereof rests on the projecting end 9 of the screw 9 or on the shoulder 36 as the case may be.
  • the afore described mechanism comprises the essential part of the alarm, which detects a dangerous rise in temperature and releases a detained alarm mechanism at a predetermined degree of temperature.
  • the alarm mechanism may be of any suitable character, wherein mechanism may be operated by the movement of the free end of the coil 7 and lever 8 to ring a bell or gong, to blow a whistle, to set olf explosives, or to otherwise indicate danger.
  • the first mentioned gong mechanism comprises a gong 30, a gear wheel 29 made to revolve in the direction of the arrow by any convenient means (not shown), lugs or 'fingers 28 on the wheel 29 for striking a pallet 26 to vibrate the hammer 27 to ring the gong, a pawl or detent 24 engaging the gear wheel 29 (when parts are in set position to detain its movement, a spring position with respect to ,65y The upper arm 8 of Vlows wheel 29EL to ring the gong 30a.
  • detent 24 tending to release detent 24: from the gear wheel 29, and a cord or wire 12 connected to the pawl 21 and trip 10, and by its tension holding pawl 24 in engagement with wheel 29. It is readily seen that when detent or pawl- 2-1 is released that the wheel 29 is free to turn and ring the gong. As this mechanism is old an extensive description thereof is notthought necessary.
  • the latter gong ringing mechanism comprises a gong 30a, a gear wheel 29ai made to revolve in the direction of the arrow by any well known means (not shown), pallets 31 and 32 adapted to be oscillated by the movement of wheel 29:L to vibrate hammer 27fL and thus ring the gong, a detent 24a engaging wheel 29aM and preventing ⁇ movement thereof (when in setposit-ion), ⁇ and a push rod 17 connected to the pawl 24;a and resting against screw 16 in recess 35 of arm 8. 'Ihus when rod 17 is pushed by arm 8, the wheel 29a is free to turn and ring the gong.
  • the detecting apparatus may be used to set off other alarm mechanisms, including the closing or opening of an electric circuit.
  • the parts are set as shown in Fig. 1, when the temperature is normal. New, as the temperature rises, the wire 7 expands faster than the plate 5 and necessarily the free end thereof is forced outward thereby,
  • the spiral arrangement of wire 7 provides a compact means for obtainingthe expansion of a comparative long piece of wire or the like.
  • the cord or wire 12 being under tension, when t-he parts are in set position, assures the setting off of the alarm in case of its breakage or disarrangementas well as in case of fire, should other accidents occur.
  • a bed plate having a low coeflicient of expansion a coil of wire of larger coeflicientof expansion mounted on the said plate and having one end free, a plurality of inwardly expanding guides for the said wire, a trip held in normal position by the free end of the said wire, an alarm mechanism, a detent therefor, and means communicating between the said trip and 1 the detent, whereby the said trip is released on a predetermined rise in t-emperature and the said detent disengaged from the alarm mechanism.
  • a fire alarm mechanism the combination of a bed plate having a low ccetcient of expansion, a coil of wire of larger coe'l'licient of expansion mounted on the said plate and having one end free, a plurality of inwardly expanding guides for the said wire, a swingable arm connected to the free end of the said wire, a trip adapted to rest against the said arm, an alarm mechanism, a detent therefor, and a tension cord attached to the said trip and detent, whereby the 1 slaclrening of the tension of the said cord, when the said arm is swung and the trip released due to the expansion of the said wire on a predetermined rise in temperature, allows the detent to be disengaged from the alarm mechanism.
  • a fire alarm mechanism the combination of a bed plate having a low coeflicient of expansion, a coil of wire of larger coeflicient of expansion mounted on the said plate and having one end free, a plurality of inwardly expanding guides for the said wire, a trip held in normal position by the free end of the said wire, an alarm mechanism, a detent therefor, and a tension cord ⁇ connecting the said trip and detent, whereby the tension of the said cord is slackened and the detent disengaged from the alarm mechanism when the trip is released due to a predetermined rise in temperature.
  • a fire alarm mechanism the combination of a bed plate having a low coeliicient of expansion, a spiral coil of wire of larger coeHicient of expansion mounted on the said plate and having its inner end secured to the 1 said plate and its outer end free, a plurality oil inwardly expanding guides for the said wire, an arm pivoted to the plate in an approximately radial position with respect to the said coil, the said free end of the wire being connected to the said arm near its fulcrumed point, a trip adapted to rest against the outer end of said arm, an alarm mechanism, a detent therefor, and a tension cord attached to the said trip and detent, whereby the slackening of the tension of the said cord, when the said arm is swung and the trip released due to the expansion of the said wire on a predetermined rise in temperature, allows the detent to be disengaged from the alarm mechanism.
  • a fire alarm mechanism the combination of a bed plate, having alow coelicient of expansion, a coil of wire of larger coeiiicient of expansion mounted on the said plate having one end free, a plurality of guides for the said coil. of wire, and means communicating between the free end of the said wire and an alarm mechanism, whereby the expansion of the said wire is utilized to set the alarm mechanism into action.
  • a re alarm mechanism the combination of a bed plate having a low coeliicient of expansion, a coil of wire of larger coeiiicient of expansion mounted on the said plate having one end free, a plurality of guides for the said coil of wire, a trip held in normal position by the free end of the said wire, an. alarm mechanism, a detent therefor, and means communicating between the said trip and detent, whereby the said trip is released on a predetermined rise in temperature and the said detent disengaged from the alarm mechanism.
  • a ire alarm mechanism the combination of a bed plate having a low coeliicient of expansion, a coil of wire of larger coefiicient of expansion mounted on the said plate having one end free, a plurality of guides for the said coil of wire, a trip held in normal position by the free end of the said wire, an alarm mechanism, a detent therefor, and a tension cord connectin the said trip and detent, whereby the tension of the said cord is slackened and the ydetent disengaged from the alarm mechanism when the trip is released due to a predetermined rise in temperature.
  • a fire alarm mechanism the combination of a bed plate having a low coefcient vof expansion, a coil of wire of larger coetlicient of expansion mounted on lthe said plate having one end free, a plurality of guides for said wire, a swingable arm connected to the :tree end of the said wire, a trip adapted to rest against the said arm, an alarm mechanism, a detent therefor, and a tension cord attached to the said trip and connected with the detent, wher by the slaclening of the tension of the sai cord, when the said arm is swung and the trip released duc to the expansion of the said wire on a predetermined rise in temperature, allows the detent to be disengaged from the alarm mechanism.
  • a bed plate having a low coeflicient of expansion a coil of wire mounted on the said plate having one end free, a plurality of inwardly expanding guides for said wire, an alarm mechanism, and means communicating between the free end of the said wire and the alarm mechanism, whereby the expansion of the said guides is utilized to set the alarm mechanism into action.
  • a fire alarm mechanism the combination of a bed plate having a low coeiiicient of expansion, a coil of Wire having a larger coeicient of expansion mounted thereon having one end free, a plurality of inwardly expanding guides for said wire, an alarm mechanism and means communicating between the free end of the saidwire and the alarm mechanism, whereby the joint eXpansion of the said wire and guides is utilized to set the alarm mechanism into action.

Description

J. ENRIGHT.
FIRE ALARM. APPLIOATION FILED 00T. 2o,` 1910.
WITNESSES NITED STATES PATENT OFFICE.
JOHN ENRIGH'I, OF CLEVELAND, OHIO.
' isIRE-ALAJalvr.v
To all 'whom t may concern.'
Be it known that I, JOHN ENRIGHT, a citizen of the United States, residing at Cleveland, in the county of Cuyahoga. and State of Ohio, have invented certain new and useful Improvements in Fire-Alarms, of which the following is a specification.
This invention relates to lire alarms and especially to automatic re alarms.
The object of my invention is to produce an automatic heat detector and fire alarm, by means of which destructive fires in hotels, school houses, and other buildings including` the holds of vessels, may be detected before attaining dangerous headway, in order to quickly extinguish same. I accomplish this result by utilizing the expansion of a wire or rod, due to the rise in temperature, to release certain mechanism which detains an alarm.
The invention embodies a novel arrangement and construction of parts as hereinafter described and as shown in the accompanying drawings, in which- Figure 1 is a plan view of the detector and two alarm connections, parts broken away. Fig. 2 is a section on the line 2*?. of Fig. 1. Fig. 3 is a section on the line 3 3 of Fig. 1. Fig. 4 is a plan view in detail of a modification. Fig. 5 is a view similar to Fig. 2 of a modification, part broken away. Fig. 6 is a perspective of a detail.
Similar reference characters indicate similar parts in the several figures shown in the accompanying drawings.
Reference being had to the drawings, 5 indicates a bed plate composed of porcelain or other suitable material having a low coefcient of superficial expansion, which plate may be held in set position against a wall, ceiling, or other suitable location by bolts 6.
Mounted on the said plate 5 is a spiral wire or coil 7 of suitable thickness and material, having a large coefficient of linear expansion. The said spiral wire 7 passes snugly between a plurality of radial arranged rollers or guides 23 pivoted in housings 13, which have a comparative large co` efficient of expansion. The screws 14 which secure the outer ends of the housings to plate 5 are rigid, while the screws 15 which connect the inner ends of the housings to plate 5 are loose in the slots 34 in the said plate. Housings 13 and rollers 23 preserve the shape and position of the spiral wire 7. The inner end of the spiral wire or coil 7 Specification of Letters Patent.
Application filed October 20, 1910.
Patented Jan. 30,1912. serial No. 588,030.
is made fast to the plate 5 by screw 33 and clamp block 18, while the outer or free end of the said coil is secured to the upper arm 8 of a lever or rocker 8 near the fulcrumed point, by means of screw 2O and clamp block 19. The lever 8 is pivoted to the plate 5 by a screw 21 and is spaced therefrom by block 22. The lever or rocker 8 is in an approximate radial the spiral or coil 7. the lever 8 carries an adjusting screw 9 at its outer end, having a projecting squared end 9. The lower arm 8 has a recess 35 and an adjusting screw 16 passing into same from the opposite side of the said arm 8. In the modified form shown in Fig. 4, a spring 36 is secured to the end of the arm 8 having an outward tension, which provides a shoulder 36. A set screw 9a holds the said spring to any desired adjustment. In the two forms shown the projection 9 and the shoulder 36 both have the same function as will be seen in the hereinafter description. Either form may be used as desired. A trip l0 is pivoted adjacent the end of arm 8 at 11 and when the coil is in normal position the inner end or arm thereof rests on the projecting end 9 of the screw 9 or on the shoulder 36 as the case may be.
The afore described mechanism comprises the essential part of the alarm, which detects a dangerous rise in temperature and releases a detained alarm mechanism at a predetermined degree of temperature.
The alarm mechanism may be of any suitable character, wherein mechanism may be operated by the movement of the free end of the coil 7 and lever 8 to ring a bell or gong, to blow a whistle, to set olf explosives, or to otherwise indicate danger.
For purpose of illustration, two gong ringing mechanisms have been shown in the drawings, one having connection to lever 10 and the other to the lower end of arm 8". The former being adapted to be placed at a distance from the detector, while the latter is adapted to be placed adjacent the detector. The first mentioned gong mechanism comprises a gong 30, a gear wheel 29 made to revolve in the direction of the arrow by any convenient means (not shown), lugs or 'fingers 28 on the wheel 29 for striking a pallet 26 to vibrate the hammer 27 to ring the gong, a pawl or detent 24 engaging the gear wheel 29 (when parts are in set position to detain its movement, a spring position with respect to ,65y The upper arm 8 of Vlows wheel 29EL to ring the gong 30a.
25 tending to release detent 24: from the gear wheel 29, and a cord or wire 12 connected to the pawl 21 and trip 10, and by its tension holding pawl 24 in engagement with wheel 29. It is readily seen that when detent or pawl- 2-1 is released that the wheel 29 is free to turn and ring the gong. As this mechanism is old an extensive description thereof is notthought necessary. The latter gong ringing mechanism comprises a gong 30a, a gear wheel 29ai made to revolve in the direction of the arrow by any well known means (not shown), pallets 31 and 32 adapted to be oscillated by the movement of wheel 29:L to vibrate hammer 27fL and thus ring the gong, a detent 24a engaging wheel 29aM and preventing` movement thereof (when in setposit-ion),`and a push rod 17 connected to the pawl 24;a and resting against screw 16 in recess 35 of arm 8. 'Ihus when rod 17 is pushed by arm 8, the wheel 29a is free to turn and ring the gong. In a similar manner the detecting apparatus may be used to set off other alarm mechanisms, including the closing or opening of an electric circuit.
In use, the parts are set as shown in Fig. 1, when the temperature is normal. New, as the temperature rises, the wire 7 expands faster than the plate 5 and necessarily the free end thereof is forced outward thereby,
thus swinging lever 8 with it. At a predetermined temperature, generally from about 180 to BOO degrees, by means of the adjusting screw 9, the trip 10 slips off of projection 9, and the slacking of wire or cord 12 allows the spring 25 to force pawl out of engagement with the wheel 29 to ring the gong 30.V At the same time the movement of the push rod 17 releases detent 24a and al- Housings 18 in expanding inwardly due to the slot 31 tend to cramp the wire 7, and assist in swinging lever 8 by forcing the free end of the wire outward. If desired, by increasing the number of cords or wires 12 a similar number of alarms at various locations may be set olf. The lower arm 8'/ of the lever 8 and attached parts can be dispensed with. Any movement of the free end of the coil 7 is enlarged at the end of the arm 8 as will be understood. The spiral arrangement of wire 7 provides a compact means for obtainingthe expansion of a comparative long piece of wire or the like. The cord or wire 12 being under tension, when t-he parts are in set position, assures the setting off of the alarm in case of its breakage or disarrangementas well as in case of lire, should other accidents occur.
Various other alterations and modiiications of the device can be made within the scope of the appended claims, and no limitat-ions are inferred by the specific structure shown and described. For example, as`
shown in Fig. 5, in which the inner end of the wire 7 is not made rigid with 'the plate by clamp block 1S and screw 33, but is secured to the lower arm 8 of the lever 8 by clamp block 1Sa and screw 33. In this construction, as the wire expands, the central portion of the wire remains neutral while both ends extend to move or swing Vthe lever 8 for the purpose described, but
the extension of either of the ends of the wire is only one-half that of the extension of the free end of the wire shown in Fig. 1.
Having described my invention, what I claim as new is:-
1. In a lire alarm mechanism, the combination of a bed plate having a low coeflicient of expansion, a coil of wire of larger coeflicientof expansion mounted on the said plate and having one end free, a plurality of inwardly expanding guides for the said wire, a trip held in normal position by the free end of the said wire, an alarm mechanism, a detent therefor, and means communicating between the said trip and 1 the detent, whereby the said trip is released on a predetermined rise in t-emperature and the said detent disengaged from the alarm mechanism.
2. In a fire alarm mechanism, the combination of a bed plate having a low ccetcient of expansion, a coil of wire of larger coe'l'licient of expansion mounted on the said plate and having one end free, a plurality of inwardly expanding guides for the said wire, a swingable arm connected to the free end of the said wire, a trip adapted to rest against the said arm, an alarm mechanism, a detent therefor, and a tension cord attached to the said trip and detent, whereby the 1 slaclrening of the tension of the said cord, when the said arm is swung and the trip released due to the expansion of the said wire on a predetermined rise in temperature, allows the detent to be disengaged from the alarm mechanism.
3. In a fire alarm mechanism, the combination of a bed plate having a low coeflicient of expansion, a coil of wire of larger coeflicient of expansion mounted on the said plate and having one end free, a plurality of inwardly expanding guides for the said wire, a trip held in normal position by the free end of the said wire, an alarm mechanism, a detent therefor, and a tension cord` connecting the said trip and detent, whereby the tension of the said cord is slackened and the detent disengaged from the alarm mechanism when the trip is released due to a predetermined rise in temperature.
11. In a fire alarm mechanism, the combination of a bed plate having a low coeliicient of expansion, a spiral coil of wire of larger coeHicient of expansion mounted on the said plate and having its inner end secured to the 1 said plate and its outer end free, a plurality oil inwardly expanding guides for the said wire, an arm pivoted to the plate in an approximately radial position with respect to the said coil, the said free end of the wire being connected to the said arm near its fulcrumed point, a trip adapted to rest against the outer end of said arm, an alarm mechanism, a detent therefor, and a tension cord attached to the said trip and detent, whereby the slackening of the tension of the said cord, when the said arm is swung and the trip released due to the expansion of the said wire on a predetermined rise in temperature, allows the detent to be disengaged from the alarm mechanism.
5. In a fire alarm mechanism, the combination of a bed plate, having alow coelicient of expansion, a coil of wire of larger coeiiicient of expansion mounted on the said plate having one end free, a plurality of guides for the said coil. of wire, and means communicating between the free end of the said wire and an alarm mechanism, whereby the expansion of the said wire is utilized to set the alarm mechanism into action.
6. In a re alarm mechanism, the combination of a bed plate having a low coeliicient of expansion, a coil of wire of larger coeiiicient of expansion mounted on the said plate having one end free, a plurality of guides for the said coil of wire, a trip held in normal position by the free end of the said wire, an. alarm mechanism, a detent therefor, and means communicating between the said trip and detent, whereby the said trip is released on a predetermined rise in temperature and the said detent disengaged from the alarm mechanism.
7 In a ire alarm mechanism, the combination of a bed plate having a low coeliicient of expansion, a coil of wire of larger coefiicient of expansion mounted on the said plate having one end free, a plurality of guides for the said coil of wire, a trip held in normal position by the free end of the said wire, an alarm mechanism, a detent therefor, and a tension cord connectin the said trip and detent, whereby the tension of the said cord is slackened and the ydetent disengaged from the alarm mechanism when the trip is released due to a predetermined rise in temperature.
8. In a fire alarm mechanism, the combination of a bed plate having a low coefcient vof expansion, a coil of wire of larger coetlicient of expansion mounted on lthe said plate having one end free, a plurality of guides for said wire, a swingable arm connected to the :tree end of the said wire, a trip adapted to rest against the said arm, an alarm mechanism, a detent therefor, and a tension cord attached to the said trip and connected with the detent, wher by the slaclening of the tension of the sai cord, when the said arm is swung and the trip released duc to the expansion of the said wire on a predetermined rise in temperature, allows the detent to be disengaged from the alarm mechanism.
9. In a re alarm mechanism, the combination of a bed plate having a low coeflicient of expansion, a coil of wire mounted on the said plate having one end free, a plurality of inwardly expanding guides for said wire, an alarm mechanism, and means communicating between the free end of the said wire and the alarm mechanism, whereby the expansion of the said guides is utilized to set the alarm mechanism into action.
l0. In a fire alarm mechanism, the combination of a bed plate having a low coeiiicient of expansion, a coil of Wire having a larger coeicient of expansion mounted thereon having one end free, a plurality of inwardly expanding guides for said wire, an alarm mechanism and means communicating between the free end of the saidwire and the alarm mechanism, whereby the joint eXpansion of the said wire and guides is utilized to set the alarm mechanism into action.
In testimony whereof I do affix my signature in presence of two witnesses.
JOHN ENRIGHT.
Witnesses:
EUGENE E. WOLF, MONROE E. MILLER.
Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C.
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