Classifications

• • G—PHYSICS
  • G08—SIGNALLING
  • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
  • G08B17/00—Fire alarms; Alarms responsive to explosion
  • G08B17/10—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means
  • G08B17/103—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means using a light emitting and receiving device
  • G08B17/107—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means using a light emitting and receiving device for detecting light-scattering due to smoke
• • G—PHYSICS
  • G08—SIGNALLING
  • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
  • G08B17/00—Fire alarms; Alarms responsive to explosion
  • G08B17/10—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means
  • G08B17/11—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means using an ionisation chamber for detecting smoke or gas
  • G08B17/113—Constructional details

Definitions

• the present invention relates to a device for detecting smoke, for example in a room.
• Smoke detectors are known in many forms and designs and are on the market. However, almost all of them work according to one principle. To be detected, the smoke must flow through the smoke detector. The method is known as the scattered light method and requires the smoke to come into contact with the sensor. The consequence of this is that smoke detectors must protrude from the ceiling, flush installation is not possible according to the applicable European standard EN54. During maintenance, it is necessary to dismantle the entire sensor head and send it to the manufacturer. In practice, the sensor heads are replaced by new ones, since it is not possible to wait until the replaced ones come back, repaired or serviced by the manufacturer. As a result, it is necessary that the double amount of smoke detectors is kept in stock by the maintenance companies.
• each smoke detector is wired to the control cabinet.
• the present invention has for its object a device of the above. To create a way with which smoke is detected in a simple manner, contamination or sabotage is recognized or the smoke detector is tested for its functionality. This should also make the European standard EN54 for smoke detection easier and easier to meet.
• a transmitter for emitting radiation that can be reflected by the smoke and a receiver that recognizes the radiation reflected by the smoke.
• the type of radiation is of minor importance.
• it can be a laser or light radiation of any wavelength (preferably in the infrared range), but ultrasound is also considered, or radiation that works according to the ionization principle. All radiation sources can be used here, which ensure that the emitted radiation is reflected by the smoke particles.
• the great advantage of the device according to the invention is that the smoke detector no longer has to be traversed by the smoke, so that installation flush with the ceiling is possible.
• a cover should preferably be provided in front of the transmitter or the receiver. This cover ensures that all elements necessary for the measurement are not contaminated.
• the transmitter emits radiation into the room immediately below the smoke detector. If the radiation hits smoke particles, which form a reflection barrier, the receiver can recognize the reflected radiation. The smoke is also detected.
• the reflection distance i.e. the reflection distance, also results from the selected radiation or incidence angle. , the distance between the smoke detector and smoke.
• Self-diagnosis is preferably also provided in the device according to the invention.
• a control receiver is assigned to the transmitter in front of the cover.
• the transmitter emits a short pulsed radiation. If this radiation is confirmed by the control receiver, the function of the transmitter is guaranteed.
• the control receiver monitors the radiation channel. A short, pulsed transmission radiation is emitted by a control transmitter to monitor the receiver. If this is confirmed by the receiver, the function of the receiver is guaranteed.
• the cover serves as a reflective surface. If the radiation is reflected on the reflection surface, it is detected by its own transmitter or receiver, which determines that the cover has become opaque to radiation.
• the degree of contamination of the cover can also be checked. If dust or dirt particles are deposited on the cover, the signal value of the own receiver assigned to the transmitter and of the main receiver increases steadily. If a critical pollution value is reached, a maintenance signal is issued. The resulting maintenance usually only means cleaning the cover. It is not necessary to remove or replace the smoke detector sensor.
• the new device according to the invention for detecting smoke can also be influenced by extraneous radiation.
• a filter should be placed upstream of the receiver, which filters out this external radiation. If, for example, light is used as radiation, the sensor receives the entire incident light radiation, but only converts the light radiation with the emitted frequency into DC voltage, which then results in the transmission signal. The rest of the light radiation is converted into AC voltage and set to zero.
• the device according to the invention is preferably controlled in such a way that not every deviation of the reflection from an alarm or the like. leads.
• an insect flyby which coincidentally reflects the radiation, should be ignored, just like a cleaning lady with a feather duster. Therefore, a plurality of recognition processes are added in succession by a control program. An alarm is only triggered if several detection processes successively detect a deviation in the reflection. Even an abrupt increase in the deviation of the reflection does not yet lead to a message, since it is known that smoke tends to lead to a continuous increase in a reflection deviation.
• the entire device is preferably designed as a unit. It can be designed as a stand-alone version, with the connections being controlled by simple relay outputs. However, the entire system is preferred by a flexible one
• Microprocessor system can be controlled via a BUS.
• Each smoke detector communicates with a control center via BUS.
• a cable break can be identified by an initialization sequence, resulting in a completely failed
• the error message includes the level of contamination or sabotage and the number of the device on which the event occurred.
• the device according to the invention is particularly suitable for installation in ducts of air conditioning systems, these devices generally being used to trigger fire dampers.
• smoke detectors For the previous smoke detectors in air conditioning ducts, it was important that the smoke detector was set in the correct direction to the flow direction. This is why errors often occurred here in the past, especially when the flow direction was inconsistent and changed.
• the flow direction is completely unimportant for the device according to the invention for detecting smoke, so that great care does not have to be taken to arrange the device in the duct.
• Figure 1 is a schematic representation of an inventive device for detecting smoke
• FIGS. 2 to 4 schematic representation of various functions of the inventive device for detecting smoke.
• An inventive device for detecting dashed smoke 1 has a transmitter 2 and a receiver 3.
• Transmitter 2 and receiver 3 are preferably located in a housing 4, which can be embedded in a ceiling, for example.
• a separate receiver 9 and a control receiver 10 are preferably assigned to the transmitter 2.
• a separate transmitter 11 and a control transmitter 12 are in turn assigned to the receiver 3.
• the actual smoke detection takes place via the transmitter 2 and the receiver 3 according to FIG. 2. If there is one
• Smoke measuring zone smoke 1 the radiation 6 emitted by the transmitter 2 is reflected on the smoke 1 and by measured the receiver 3.
• the intensity of the reflection is a measure of the smoke density.
• the reflection distance results from a selected radiation or incidence angle, ie it can also be determined how far the smoke is from the device according to the invention.
• the own receiver 9 for the transmitter 2 and the own transmitter 11 for the receiver 3 are provided, as shown in FIG. If the cover 5 or 7 is dirty or taped, the radiation cannot penetrate through the cover 5/7 but is reflected. This reflected radiation is determined by the receiver 9 or the receiver 3.
• the system can be set so that a percentage of contamination is also determined. This means, for example, that an error message is only given when the pollution has exceeded a certain level.
• the setting can also be done in such a way that the smoke detection remains active up to a certain level as the level of contamination increases.
• a self-test of the device according to the invention is also desired. This is shown in Figure 4.
• the control receiver 10 and the control transmitter 12 are used for the self-test.
• the transmitter 2 is tested in that its signal is received directly by the receiver 10. If the receiver 10 registers the radiation, it is established that the transmitter is functional.
• the receiver 3 is tested in that the transmitter 12 illuminates it. If the receiver 3 receives the radiation, it is functional. If the transmitter and / or receiver is defective, an error message is output.

Landscapes

• Chemical & Material Sciences (AREA)
• Analytical Chemistry (AREA)
• Business, Economics & Management (AREA)
• Emergency Management (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Fire-Detection Mechanisms (AREA)
• Investigating Or Analysing Materials By Optical Means (AREA)

Priority Applications (1)

Applications Claiming Priority (3)

Publications (3)

Family

ID=7926832

Family Applications (1)

Country Status (6)

Families Citing this family (15)

Family Cites Families (10)

• 1999
  • 1999-10-26 DE DE19951403A patent/DE19951403B4/de not_active Revoked
• 2000
  • 2000-08-12 WO PCT/EP2000/007871 patent/WO2001031602A1/fr active IP Right Grant
  • 2000-08-12 DE DE50002015T patent/DE50002015D1/de not_active Expired - Lifetime
  • 2000-08-12 AT AT00956437T patent/ATE239281T1/de active
  • 2000-08-12 ES ES00956437.8T patent/ES2198348T5/es not_active Expired - Lifetime
  • 2000-08-12 AU AU68380/00A patent/AU6838000A/en not_active Abandoned
  • 2000-08-12 EP EP00956437.8A patent/EP1224641B2/fr not_active Expired - Lifetime

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events