Wireless smoke detection system

Information

  • Patent Grant
  • 6420973
  • Patent Number
    6,420,973
  • Date Filed
    Saturday, January 23, 1999
    27 years ago
  • Date Issued
    Tuesday, July 16, 2002
    23 years ago
  • Inventors
  • Examiners
    • Wu; Daniel J.
    • Nguyen; Tai T.
    Agents
    • Kenyon & Kenyon
Abstract
A wireless detection system for monitoring a predetermined area for an emergency situation. The wireless smoke detection system includes a plurality of detector units strategically positioned throughout the monitored area. Each of the plurality of detector units include a detector for sensing one of a characteristic and condition within a section of the monitored area and generating a signal indicative of the monitored. A signal processor is connected within each detector unit for analyzing the signal generated by the detector and upon determining if the signal is above a predetermined level generating an emergency signal. A transmitter is provided for transmitting the emergency signal to a plurality of receiver units strategically positioned about the monitoring area. Each receiver unit includes an alarm for generating an alarm signal and thereby alert persons to the emergency situation at a position within the monitored area. The detector can be at least one of a photoelectric smoke detector, an ionization type detector, a combination carbon monoxide and smoke detector, a carbon monoxide detector, a near infrared detector and a hazard detector.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates generally to alarms and, more specifically, to a smoke detection system able to detect smoke in any area of a structure and wirelessly transmit an alarm signal to receivers positioned throughout the structure, alerting occupants throughout the structure as to the detected situation.




2. Description of the Prior Art




Numerous types of smoke alarms have been provided in the prior art. For example, U.S. Pat. Nos. 5,587,705; 5,745,040; 5,774,038 and 5,786,767 all are illustrative of such prior art. While these units may be suitable for the particular purpose to which they address, they would not be as suitable for the purposes of the present invention as heretofore described.




U.S. Pat. No. 5,587,705




Inventor: Gary J. Morris




Issued: Dec. 24, 1996




The battery powered smoke detector of this invention is designed to provide an early warning of the presence of an environmental condition of fire or smoke to persons in remote areas of a building with respect to the location of the environmental condition. The smoke detector sensing the environmental condition emits an audible alarm of continuous tone, while emitting a frequency modulated radio signal directly to other like smoke detectors to activate their alarms in a manner indicative of the location of the smoke detector sensing the environmental alarm condition. Rechargeable light modules separate from the smoke detector are included that receive the frequency modulated radio signal from the smoke detector sensing the environmental alarm condition and illuminate paths of egress for the duration of the alarm condition or in the case of 120V AC power failure. All components of the system are easy to install due to the modular design and conventional power sources. An intermittent activation of the frequency modulated receiving circuitry in the smoke detector unit conserves battery energy.




U.S. Pat. No. 5,745,040




Inventor: Lisa M. Loughridge




Issued: Apr. 28, 1998




An outdoor alerting device for smoke alarms including an alarm detecting and alerting device drive unit and an exterior alerting device including a loudspeaker installed within a housing and a light display unit attached to the housing and having a light bulb. The alarm detecting and alerting device drive unit includes an alarm detection circuit including a microphone having a microphone output in electrical connection with an amplifier circuit for converting the audible alarm into an amplified electrical microphone signal. The amplified electrical microphone signal is then passed through a band pass filter that is tuned to the main audible output frequency of the audible alarm of the smoke detector to produce a filtered microphone signal. The filtered microphone signal is then passed through a rectifier circuit to convert the filtered microphone signal into a DC microphone signal. The DC microphone signal is then output to the signal input of a comparator. The reference input of the comparator is supplied with a predetermined reference voltage such as through a voltage divider circuit. The output of the comparator is used to trigger the exterior alerting device after being passed through a delay network.




U.S. Pat. No. 5,774,038




Inventor: Dana L. Welch et al.




Issued: Jun. 30, 1998




This invention relates to an improved safety monitor which comprises a main monitor and a remote monitor which are in communication with each other. The main monitor has a main monitor detector and a main monitor fire/smoke alarm integrally electronically connected to a main monitor microprocessor. The main monitor detector is selected from a group consisting of monitor carbon monoxide detector, monitor carbon dioxide detector and monitor radon detector. The main monitor detector and the main monitor fire/smoke alarm send a warning signal to the remote monitor to alert the user of an adverse condition and which type. A charger base is provided to hold the main monitor and the remote monitor as well as charge the main monitor battery and remote monitor battery.




U.S. Pat. No. 5,786,767




Inventor: Joseph Severino




Issued: Jul. 28, 1998




A home safety system comprising a smoke detector, a carbon monoxide detector and a microphone connected to a transmitter. The smoke detector is powerable by a/c current and by a battery and comprises a sensor for sensing smoke connected to an audible alarm signal. The carbon monoxide detector is powerable by a/c current and by a battery and comprises a sensor for sensing the presence of carbon monoxide connected to an audible alarm signal. The transmitter comprises means for communicating signals from the carbon monoxide detector and smoke detector to a remote location. The invention further comprises an emergency lighting system connected to the carbon monoxide detector and smoke detector. The light system is powered by a battery and adapted to turn on in the event of a power failure, a signal from the smoke detector or a signal from the carbon monoxide detector. The lighting system can also be used as a night light. A portable receiver receives signals from the transmitter and broadcasts the signals to alert an individual monitoring the conditions to the presence of smoke or carbon monoxide.




SUMMARY OF THE PRESENT INVENTION




The present invention relates generally to alarms and, more specifically, to a smoke detection system able to detect smoke in any area of a structure and wirelessly transmit an alarm signal to receiver units positioned throughout the structure, alerting occupants throughout the structure as to the detected situation.




A primary object of the present invention is to provide a wireless smoke detection system that will overcome the shortcomings of prior art devices.




Another object of the present invention is to provide a wireless smoke detection system which is able to provide communication between a plurality of detector units and a plurality of receiver units positioned within an area or structure to be monitored.




A further object of the present invention is to provide a wireless smoke detection system which is able to monitor a plurality of hazardous conditions and relay an emergency signal to other receivers in the system upon detection of an emergency situation.




A yet further object of the present invention is to provide a wireless smoke detection system wherein the system is provided to alert individuals within a structure or area being monitored as to the existence of an emergency situation within the area or structure.




A still further object of the present invention is to provide a wireless smoke detection system including a plurality of detector units able to communicate wirelessly with receiver units whereby one of the detector units is able to trigger generation of an alarm signal to the receiver units upon detection of an emergency situation.




A further object of the present invention is to provide a wireless smoke detection system wherein the detector units are able to detect at least one of smoke, carbon monoxide and any other hazard above a predetermined level.




Another object of the present invention is to provide a wireless smoke detection system wherein each of the detector units are strategically positioned in the area to be monitored and include both a transmitter and receiver.




Another object of the present invention is to provide a wireless smoke detection system that is simple and easy to use.




A still further object of the present invention is to provide a wireless smoke detection system that is economical in cost to manufacture.




Additional objects of the present invention will appear as the description proceeds.




A wireless detection system for monitoring a predetermined area for an emergency situation is described by the present invention. The wireless smoke detection system includes a plurality of detector units strategically positioned throughout the monitored area. Each of the plurality of detector units include a detector for sensing one of a characteristic and condition within a section of the monitored area and generating a signal indicative of the monitored. A signal processor is connected within each detector unit for analyzing the signal generated by the detector and upon determining if the signal is above a predetermined level generating an emergency signal. A transmitter is provided for transmitting the emergency signal to a plurality of receiver units strategically positioned about the monitoring area. Each receiver unit includes an alarm for generating an alarm signal and thereby alert persons to the emergency situation at a position within the monitored area. The detector can be at least one of a photoelectric smoke detector, an ionization type detector, a combination carbon monoxide and smoke detector, a carbon monoxide detector, a near infrared detector and a hazard detector.




To the accomplishment of the above and related objects, this invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that changes may be made in the specific construction illustrated and described within the scope of the appended claims.











BRIEF DESCRIPTION OF THE DRAWING FIGURES




Various other objects, features and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views.





FIG. 1

is a perspective view of a structure being monitored by the wireless smoke detection system of the present invention;





FIG. 2

is a front view of a detector and transmitter of the wireless smoke detection system of the present invention;





FIG. 3

is a block diagram of a detector and receiver of the wireless smoke detection system of the present invention, one detector triggering the receiver alarm upon detection of an emergency situation;





FIG. 4

is a front perspective view of a receiver unit of the wireless smoke detection system of the present invention;





FIG. 5

is a side view of a receiver unit of the wireless smoke detection system of the present invention;





FIG. 6

is a block diagram of a detector unit of the wireless smoke detection system of the present invention;





FIG. 7

is a block diagram of a receiver unit of the wireless smoke detection system of the present invention;





FIG. 8

is a schematic diagram of the transmitter section of a detector unit of the wireless smoke detection system of the present invention;





FIG. 9

is schematic diagram of the receiver of the wireless smoke detection system of the present invention;





FIG. 10

is a schematic diagram of an ionization type smoke detector for use in a detector unit of the wireless smoke detection system of the present invention; and





FIG. 11

is a schematic diagram of an photoelectric type smoke detector for use in a detector unit of the present invention.











DESCRIPTION OF THE REFERENCED NUMERALS




Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several views, the Figures illustrate the wireless smoke detection system of the present invention. With regard to the reference numerals used, the following numbering is used throughout the various drawing figures.






10


wireless smoke detection system of the present invention






11


structure being monitored by wireless smoke detection system






13


detector unit






14


arrow indicating transmission of a signal upon detecting an emergency






15


receiver unit






16


fire within a room of the structure






18


arrow indicating receipt of transmitted signal






20


lines representing audible alarm signal






22


visual indicator alarm






24


audible alarm






26


transmitter within detector unit






28


detector within detector unit






30


alarm within detector unit






31


alarm within receiver unit






32


receiver within receiver unit






33


conventional electrical outlet






34


processor






35


housing of receiver unit






36


power supply






37


power indicator light of receiver unit






38


encoder






39


stabilizing foot of receiver unit






40


timer






41


audible alarm of receiver unit






42


amplifier






44


decoder






46


near infrared smoke detector






48


code switch of encoder






50


encoder






52


code switch of decoder






53


transmitter unit






54


near infrared detector






56


infrared detector signal processor






58


receiver section






60


audible alarm driver






62


ion gauge






64


ion gauge siginal processor






66


photoelectric diodes






68


photoelectric signal processor




DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several views,

FIGS. 1 through 11

illustrate the wireless smoke detection system of the present invention indicated generally by the numeral


10


.




The wireless smoke detection system


10


is illustrated installed in a building


11


in FIG.


1


. As shown in this figure, the wireless smoke detection system


10


includes a plurality of detector units


12


and a plurality of receiver units


15


strategically positioned throughout the building I


1


. The detector units


12


constantly monitor a defined section of the building


11


for a hazardous situation. When a hazardous situation such as the fire


16


is detected by one of the detector units


12


, the detector unit


12


sensing the fire


16


will generate and transmit an alarm signal represented by the arrow labeled with the numeral


14


. The transmitted signal


14


is received by the receiver units


15


of the system


10


as indicated by the arrow labeled


18


. Receipt of the transmitted signal


14


alerts the receiver units


15


to the detected emergency situation and causes the alarm of the individual receiver units


15


to be triggered. The audible alarm being generated by the detector unit sensing the emergency situation and the receiver units


15


upon receipt of the signal


18


is indicated by the arced lines labeled with the numeral


20


. Generation of the audible signal


20


alerts persons within the areas of the building


11


monitored by the system


10


to the emergency situation.




A front view of a detector unit


12


is illustrated in FIG.


2


. From this view a face side


21


of the detector unit


12


is visible. Positioned on the face side


21


is a visible alarm indicator


22


, a power indicator


23


and a speaker


24


of the audible alarm. In the figures the visual alarm is illustrated as a LED and the audible alarm is indicated as a horn for purposes of example only. In practice, the visual alarm may be any device able to produce a visible alarm signal able to alert a person within a predefined area as to the existence of an emergency situation and the audible alarm may be any device able to produce an audible alarm signal able to alert a person within a predefined area as to the existence of an emergency situation. The power indicator


23


will continually flash to indicate that sufficient power is being supplied to the unit


12


. When an emergency situation is detected by one of the detector units


12


of the system


10


, the visual alarm indicator


22


will illuminate and the speaker


24


will provide an audible alarm. Both the visual and audible alarms will alert persons within the vicinity of the triggered detector unit


12


as to the detection of an emergency situation. The detector unit


12


sensing the alarm will then transmit an alarm signal to all of the receiver units


15


causing the receiver units


15


to generate an alarm signal and alert persons in the vicinity of the receiver units to the existence of the emergency situation and to the need to possibly evacuate the monitored area.




A block diagram of a detector unit


12


communicating with a receiver units


15


is illustrated in FIG.


3


. This figure illustrates a detector unit


12


including a transmitter


26


connected to a detector


28


. The detector


28


is also connected to an alarm


30


. The alarm


30


generates the audible and visible alarm signals discussed above. When a detector unit


12


detects an emergency situation a signal is provided from the detector


28


to the transmitter


26


indicative of the sensed emergency situation. The transmitter


26


will then transmit an emergency signal


14


at a predetermined frequency to the receiver units


15


of the system


10


within the monitoring area. The receiver units


15


include a receiver


32


tuned to the correct frequency and an alarm


31


. Upon receipt of the transmitted signal


18


indicated by the arrow labeled


18


at the receiver units


15


, the alarm


31


will be triggered to generate a visual and audible alarm signal.




A receiver unit is illustrated in

FIGS. 4 and 5

and indicated generally by the numeral


15


. The receiver unit


15


plugs into a standard electrical outlet


33


. The receiver unit


15


includes a housing


35


having a power indicator light


37


positioned thereon indicating that power is being supplied to the receiver unit


15


. As can be seen from

FIG. 5

, the housing


35


may include a stabilizing foot


39


extending from a base thereof for positioning the receiver unit


15


flush against a wall. The receiver unit


15


also includes an audible alarm


41


for generating an audible alarm signal upon receipt of an emergency signal from a detector unit


12


.




A more detailed block diagram of a detector unit


12


is illustrated in FIG.


6


. This figure shows the detector


28


connected to a processor


34


. The processor


34


is connected to a power supply


36


and also to both the visual alarm


22


and the audible alarm


24


. When the detector


28


detects an emergency situation a signal indicative of such is sent to the processor


34


. The processor


34


activates the visual alarm


22


and the audible alarm


24


to alert persons in the monitored area as to the detected emergency situation. The processor


34


also sends a signal to an encoder


38


which encodes the signal for transmission to the receiver units


15


in the monitored area. The encoder


38


supplies the encoded signal to a timer


40


and to the transmitter


26


for delayed transmission of the emergency signal to the receiver units


15


. The power supply


36


is also directly connected to the encoder


38


, the timer


40


and the transmitter


26


.




A block diagram of a receiver unit


15


is illustrated in FIG.


7


. Each receiver unit


15


includes a receiver


32


connected to a power supply


33


such as the conventional electrical outlet shown in

FIGS. 4 and 5

. Upon receipt of an encoded signal from one of the detector units


12


, the receiver


32


of the receiver unit


15


supplies the received signal to an amplifier


42


and a decoder


44


. The amplifier


42


amplifies the received signal and the decoder


44


decodes the encoded and amplified signal. The decoded signal is then supplied to trigger the audible alarm


31


thereby alerting persons within the monitored area as to the detected emergency situation within the monitored area. The power supply


33


is also directly connected to the amplifier


42


and the decoder


44


.




A schematic diagram of a detector unit


12


for detecting smoke levels within an area using a near infrared type detector is illustrated in FIG.


8


. The detector


46


includes a near infrared detector


54


connected to an infrared detector signal processor


56


. The infrared detector


54


continually senses the heat level in the area being monitored and sends signals indicative of the sensed values to the infrared signal processor


56


. The infrared signal processor


56


analyzes the signals received from the infrared detector


54


to determine if an emergency condition exists. If an emergency condition is determined to exist, the infrared signal processor


56


sends a signal to the visual indicator


22


and to the audible indicator


24


. A signal indicating the emergency situation is also sent by the infrared signal processor


56


to the encoder unit


38


. The encoder unit


38


includes an encoder


50


and a code switch


48


for coding the signal for transmission. The encoded signal is provided to a transmit timer


40


for timing the signal transmission and to the transmitter


26


for transmitting the encoded signal at a predetermined frequency to the other receiver units


15


within the system


10


.




A schematic diagram of the receiver section


58


of (the receiver unit


15


is illustrated in

FIG. 9

) the receiver section


58


includes the receiver


32


tuned to receive the emergency signals from the transmitter unit


53


. The receiver


32


supplies the received signal to the amplifier


42


to amplify the received signal for the decoder


44


. The decoder


44


receives the encoded and amplified signal and decodes the signal. The decoded signal is then sent to the code switch


52


which will be activated to trigger the audible alarm


24


and thereby generate an audible alarm signal. The signal generated by the code switch


52


is sent to the audible alarm driver


60


which is also connected to the power supply


36


. The audible alarm driver


60


provides a signal to the audible alarm causing it to generate the audible alarm signal and thereby alert all persons within the area monitored by the detector unit


12


as to the existence of an emergency situation within the area being monitored by the system


10


.




An alternate type of detector


46


which may be used to detect an emergency situation is illustrated in FIG.


10


. This detector


46


is an ionization type smoke detector. This detector


46


includes an ion gauge


62


for measuring the ionization level in the atmosphere of the area monitored by the detector unit


12


. The ion gauge


62


is connected to a signal processor


64


which analyzes the signal received from the ion gauge


62


to determine if an emergency situation exists. Upon determining an emergency situation exists, the signal processor


64


sends a signal to both the visual alarm


22


and the audible alarm


24


causing each to generate an alarm signal. The alarm signal generated by both the visual alarm


22


and the audible alarm


24


alert persons in the vicinity of the monitored area that an emergency situation exists at some position within the monitored area.




A photoelectric type smoke detector used to detect an emergency situation may also be used in lieu of the detector


46


illustrated in FIG.


11


. The photoelectric type smoke detector includes photoelectric diodes


66


connected to form a circuit for measure the amount of smoke in the area monitored by the detector unit


12


. The photoelectric diodes


66


provide a signal to a photoelectric signal processor


68


. The photoelectric signal processor


68


analyzes the signal received from the photoelectric diodes


66


to determine if an emergency situation exists. Upon determining an emergency situation exists, the signal processor


68


sends a signal to both the visual alarm


22


and the audible alarm


24


causing each to generate an alarm signal. The alarm signal generated by both the visual alarm


22


and the audible alarm


24


alert persons in the vicinity of the monitored area that an emergency situation exists at some position within the monitored area.




The operation of the wireless smoke detection system


10


will now be described with reference to the figures. In operation, the detector units


12


and the receiver units


15


of the wireless smoke detection system


10


are strategically positioned throughout an area to be monitored whereby the entire area is able to be monitored. For example, if the area to be monitored is a building then a user may position the detector units


12


and receiver units


15


in each room and also in common areas between rooms such as hallways and lobbies. Thus, the entire area can be accurately monitored and wired for alerting per sons within the area as to detected emergency situations. If an open area is to be monitored then the receiver units


15


should be positioned separated from each detector unit


12


by a distance equal to the transmission range of the detector units


12


with possibly a slight overlapping of transmitting range of the detector units


12


. The detector units


12


should be separated by a distance slightly less than the individual monitoring range of each thus allowing for monitoring of the entire area.




Once positioned throughout the area to be monitored, the detectors


46


are turned on and begin monitoring the area. The receivers are also turned on by, for example, plugging them each into an electrical outlet. The detectors


46


continually send monitoring signals to their respective processor for analysis. If the processor determines that the detector


46


has monitored an emergency situation, e.g. a level of a monitored substance within the ambient atmosphere around the detector unit


12


which exceeds a predetermined limit value then an alarm signal is generated. The alarm signal is sent to the visual alarm


22


and audible alarm


24


for triggering the generation of the visual and audible alarm signals. The alarm signal is also sent to an encoder


8


to be encoded prior to transmission. After the alarm signal is encoded it is transmitted to the receiver units


15


in the area being monitored. The receiver units


15


receive the encoded signal and decode the signal in their decoder


44


. The decoded signal is then sent to trigger the audible alarm


31


to generate the audible alarm signal. The generation of the audible alarm signal alerts persons within the area being monitored that an emergency situation exists at some position within the monitored area.




The detector units of the present invention are able to monitor any of a plurality of different characteristics and qualities of the area being monitored. The detector units can each or all be any one of a near infrared smoke detector, a photoelectric smoke detector, an ionization type detector, a combination carbon monoxide and smoke detector, a carbon monoxide detector and a hazard detector.




While a preferred structure for the detector units is shown and described herein, those of ordinary skill in the art who have read this description will appreciate that there are numerous other structures for the detector units and, therefore, as used herein the phrase “means for detecting one of a characteristic and condition within a section of the monitored area” should be construed as including all such structures as long as they achieve the desired result of detecting one of a characteristic and condition within a section of the monitored area, and therefore, that all such alternative mechanisms are to be considered as equivalent to the one described herein.




From the above description it can be seen that the wireless smoke detection system of the present invention is able to overcome the shortcomings of prior art devices by providing a wireless smoke detection system which is able to alert a person in a section of the area being monitored to an emergency situation in a remote section of the monitored area. The wireless smoke detection system includes a plurality of detector units strategically positioned in the area to be monitored which include a transmitter able to provide communication with a plurality of receiver units positioned within the area to be monitored and trigger generation of an alarm signal by the receiver units upon detection of an emergency situation. The wireless smoke detection system is able to monitor a plurality of hazardous conditions such as hazardous levels of smoke, carbon monoxide and other conditions and relay an emergency signal to receiver units in the system upon detection of an emergency situation thereby alerting individuals within a structure or area being monitored to the existence of an emergency situation within the area or structure. Furthermore, the wireless smoke detection system of the present invention is simple and easy to use and economical in cost to manufacture.




It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above.




While certain novel features of this invention have been shown and described and are pointed out in the annexed claims, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention.




Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.



Claims
  • 1. A wireless detection system monitoring a predetermined area for an emergency situation, said wireless detect on system, comprising a plurality_of detector units and a plurality of receiver units strategically positioned throughout the monitored area, each of said detector units comprising:a) means for detecting one of a characterstic and condition within a section of the monitored area and generating a signal indcative of the monitored conditionl; b) signal processing means for analying said signal generated by said detecting means and upon determining if the signal is above a predetermined levele generating an emergency signal; c) means for transmitting wirelessly said emergency signal including means for delaying transmission of the signal; and d) means for generating an alarm signal upon receipt of said emergency signal from said signal processing means, said alarm signal alerting persons of an emergency situation at a position within the monitored area; and each of said plurality of receiver units includes: a) a housing containing means for receiving said emergency signal generated by any of said plurality of detector units; b) said housing also containing means connected said receiving means for generating an alarm signal upon receipt of said emergency signal; and c) said housing having means for plugging into a standard electrical outlet for receiving electrical power, a power indicator light to indicate that electrical power is being supplied to said receiver unit, and a stabilizing foot extending from a base of said housing for positioning the housing flush against a wall whereby said receivers may be moved and located where most convenient for alerting people of any emergency situation; e) each of said detectors further includes means for encoding said emergency signal prior to transmission by said transmission means and each of said receivers further include means for amplifying and decoding said emergency signal upon receipt by said receiving means; f) wherein each of said plurality of detectors is one of a near infrared smoke detector, a photoelectric smoke detector, an ionization type detector, a combination carbon monoxide and smoke detector, a carbon monoxide detector and a hazard detector.
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5568535 Sheffer et al. Oct 1996 A
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