AU2019204344A1

AU2019204344A1 - Hygiene sensor module

Info

Publication number: AU2019204344A1
Application number: AU2019204344A
Authority: AU
Inventors: Jordan Kagan Gescheit; Gavin Knight; Jason Radolnik
Original assignee: Detector Inspector Pty Ltd
Current assignee: Detector Inspector Pty Ltd
Priority date: 2018-06-20
Filing date: 2019-06-20
Publication date: 2020-01-16

Abstract

HYGIENE SENSOR MODULE Abstract There is provided a hygiene sensor module for a smoke alarm device, the sensor module comprising: a source of electromagnetic radiation; a photodiode adapted to generate a signal in response to the electromagnetic radiation from the source; an airflow restrictor located between the source and the photodiode; and a processor adapted to receive the signal and communicate a maintenance signal.

Description

HYGIENE SENSOR MODULE

Field [0001] The present invention related to a hygiene sensor module for a smoke alarm device.

Background [0002] For many years regulatory requirements have been enforced to require safety inspectors to carry out regular and on-demand safety inspections of smoke alarm devices, particularly in rental properties. Such safety compliance requirements entail scheduling of an inspection time where an occupant is expected to be present to provide access to the inspector at the time and location of the scheduled inspection, which can be inconvenient.

[0003] Such inspections are necessary to, amongst others, ensure that the smoke alarm device is sufficiently clean and unobstructed to function as intended. The inspection intervals are conservatively determined, assuming a dust, particulate, and grime accumulation on the smoke alarm device that is unlikely to occur in the vast majority of installed smoke alarm devices. Therefore, a large number of inspections are an unnecessary expenditure for property owners and an unnecessary imposition on occupants.

[0004] Further, some smoke alarm devices may be installed in areas particularly prone to dangerous hygiene degradation of the smoke alarm device, such as commercial kitchens or industrial location processing greasy substances. In these instances the maintenance intervals may be dangerously long, resulting in non-functioning smoke alarm devices that may be a danger to property and human life.

Summary of Invention [0005] It is an object of the invention to substantially overcome or at least ameliorate one or more of the above disadvantages, or at least provide a useful alternative to the above described arrangements.

[0006] In a first aspect the present invention provides a hygiene sensor module for a smoke alarm device, the sensor module comprising:

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2019204344 20 Jun 2019 a source of electromagnetic radiation;

a photodiode adapted to generate a signal in response to the electromagnetic radiation from the source;

an airflow restrictor located between the source and the photodiode; and a processor adapted to receive the signal and communicate a maintenance signal.

[0007] Preferably, the source of electromagnetic radiation is ambient light.

[0008] Preferably, the source of electromagnetic radiation is a light emitting diode.

[0009] Preferably, the light emitting diode emits light in the visible spectrum.

[0010] Preferably, the light emitting diode emits light in the infrared spectrum.

[0011] Preferably, the airflow restrictor and the photodiode are located inside the smoke alarm device [0012] Preferably, the source of electromagnetic radiation is located inside the smoke alarm device.

[0013] Preferably, the smoke alarm device is sealed such that no substantial electromagnetic radiation capable of causing the photodiode to generate a signal enters the smoke alarm device, except for the electromagnetic radiation passing through the airflow restrictor.

[0014] Preferably, a filter is also located between the photodiode and the source of electromagnetic radiation, the filter being adapted to absorb a predetermined portion of the electromagnetic radiation.

[0015] Preferably, the airflow restrictor is a mesh having a mesh spacing.

[0016] Preferably, the mesh is a fibrous material.

[0017] Preferably, the fibrous material is wool or glass fibre.

[0018] Preferably, the air flow restrictor is electrostatically active.

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2019204344 20 Jun 2019 [0019] Preferably, the airflow restrictor is mounted in a replaceable cap.

[0020] Preferably, the replaceable cap is adapted to be mounted on the smoke alarm device using a thread.

[0021] Preferably, the hygiene sensor module further comprises:

a second photodiode adapted to generate a second signal in response to the electromagnetic radiation from the source, wherein the processor compares the second signal from the second photodiode to the signal from the photodiode to generate a maintenance signal.

[0022] Preferably, the airflow restrictor is not positioned between the second photodiode and the source.

[0023] Preferably, the hygiene sensor module further comprises a second source of electromagnetic radiation, the second source being a light emitting diode, and the second photodiode is adapted to generate the second signal in response to the electromagnetic radiation from the second source.

[0024] Preferably, the second source and the second photodiode are located inside the smoke alarm device.

[0025] In a second aspect the present invention provides a smoke alarm device having the hygiene sensor module according to the first aspect.

[0026] Preferably, the smoke alarm device has two or more hygiene sensors.

[0027] Preferably, the smoke alarm device has a wireless communication module to communicate the maintenance signal to a user device.

Brief Description of Drawings [0028] Preferred embodiments of the present invention will now be described, by way of examples only, with reference to the accompanying drawings:

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2019204344 20 Jun 2019 [0029] Fig. 1 is a schematic exploded view of an embodiment of a hygiene sensor module according to the invention.

[0030] Fig. 2 is a schematic exploded view of another embodiment of a hygiene sensor module according to the invention.

[0031] Fig. 3 is a schematic perspective view of the hygiene sensor module of Fig. 1 installed on a smoke alarm device.

Description of Embodiments [0032] As shown in Fig. 1, the preferred embodiment of the hygiene sensor module 10 includes an airflow restrictor, in this case being a mesh 20, installed in a cap 30. The mesh may be a suitable fibrous material such as wool or glass fibre. Additionally, the mesh 20 may be made of a material, or from a process resulting in a material, that is electrostatically active.

[0033] The cap 30 is removably mounted by a screw thread 35 to a body 40. The body 40 has a flange 45. Inside the body 40 is a circuit board 50 on which a photodiode 55 generating a first signal is mounted. In the preferred embodiment, the cap 30, and therefore also the mesh 20, is circular and has a diameter of about 15 mm. However, the cap 30 and mesh 20 can have any shape, as long as the dimension of the mesh 20 is sufficiently large to provide a representative accumulation of particulates, grease, etc.

[0034] The first signal may be, for example, an electric current that correlates proportional to the intensity of light received by the photodiode 55. The circuit board 50 also has contacts 57 such that the photodiode 55 is able to communicate with a processor (not shown).

[0035] The processor, in turn, can communicate with a wireless communication module (not shown) so that a maintenance signal that is generated by the processor may be transmitted by the wireless communication module to a user device (not shown), such as a personal portable device, and/or a central server. The wireless communication module may communicate via any suitable communication means such as 3G, 4G, Bluetooth, Radio Frequency, WiFi and/or the like. A smoke alarm device employing a number of such communication means is disclosed in Australian patent application no. 2017279720.

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2019204344 20 Jun 2019 [0036] The hygiene sensor module 10 may be mounted on a smoke alarm device 100 as shown in Fig. 3. In this configuration, the photodiode 55 may be adapted to generate the first signal on receipt of ambient light. Alternatively, the hygiene sensor module 10 may include a light emitting diode (not shown). In this case, the photodiode 55 may be adapted to generate the first signal on receipt of the particular light, such as any wavelength in or outside the visible spectrum, including infrared, emitted by the diode.

[0037] The hygiene sensor module 10 may also be positioned inside the smoke alarm device 100, provided sufficient airflow exists to ensure that the deposition of particulates, greases etc. is representative of the accumulation of these substances on the sensors (not shown) of the smoke alarm device 100.

[0038] The hygiene sensor module 10 may also include a filter (not shown) located between the photodiode 55 and the ambient light or the light emitting diode. The filter is adapted to absorb predetermined portions of the electromagnetic spectrum, particularly frequencies not emitted by the light emitting diode.

[0039] The smoke alarm device 100 may also be equipped with multiple hygiene sensor modules 10. As best seen in Fig. 2, the smoke alarm device 100 may include a second photodiode 60 adapted to measure the ambient light without the filter and/or the mesh 20. The second photodiode 60 provides a second signal that may be compared against the first signal. Yet further, a second light emitting diode (not shown) that is unaffected by ambient light and the accumulation of particulates, grease etc. may be provided to cause the second photodiode 60 to generate the second signal. If a second light emitting diode is used, the second photodiode 60 and the second light emitting diode may be located inside the smoke alarm device 100.

[0040] Use of the hygiene sensor module 10 will now be discussed.

[0041] As dust, particulates, greases and other substances accumulate on the mesh 20, the light reaching the photodiode 55 from ambient light or the light emitting diode decreases in intensity. Correspondingly, the first signal decreases. The decreased first signal is communicated to the processor which determines whether the first signal has decreased below a pre-determined threshold indicating that maintenance of the smoke alarm device 100 is required. The

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2019204344 20 Jun 2019 maintenance signal is then transmitted by the wireless communication module to the user device.

[0042] The spacing between members of the mesh 20 may be varied, by selection of material or manufacturing process, such that accumulation of particulates, grease etc. occurs at a desired accumulation rate, compared to the accumulation rate of these substance on the sensor of the smoke alarm device 100. The material or process may also be selected to control electrostatic activity of the mesh 20, which is further able to control the desired accumulation rate. The determination of the desired accumulation rate may be performed on the basis of the location of the hygiene sensor module 10, the operating environment of the smoke alarm device 100, and the desired safety margin for ensuring that maintenance is carried out before the smoke alarm device 100 operates unsafely.

[0043] The second photodiode 60 generates the second signal, either on the basis of the ambient light if mounted externally, or on the basis of the second light emitting diode if mounted internally. The processor may compare the second signal to the first signal to generate the maintenance signal.

[0044] When maintenance of the smoke alarm device 100 occurs, the cap 30 is replaced with a like, but new, cap 30 with a clean mesh 20, such that the hygiene sensor module 10 now measures the accumulation of particulates, grease, etc. of the cleaned smoke alarm device 100.

[0045] Advantages of the hygiene sensor module 10 will now be discussed.

[0046] The inclusion of the hygiene sensor module 10 in the smoke alarm device 100 allows the continuous monitoring of accumulation of particulates, grease, etc. on the mesh 20, which is designed to correspond to the accumulation of particulates, grease etc. on the sensor of the smoke alarm device 100. It is therefore now possible to determine a maintenance requirement of the smoke alarm device 100 without an on-site inspection. It is also now possible to perform maintenance of the smoke alarm device 100 as required, rather than in an arbitrary interval determined by a rarely attained worst case standard.

[0047] The use of the hygiene sensor module 10 with ambient light causing the first signal to be generated by the photodiode 55 is a very cost-effective method of achieving this advantage.

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However, the inclusion of a light emitting diode can improve the versatility and ability to adapt the smoke alarm device 100 to a particular use case.

[0048] The flange 45 sits tightly against the body 40 and therefore seals the photodiode 55 against ambient light that has not passed through the mesh 20. This arrangement improves the accuracy of the first signal generated by the photodiode 55. To further improve the accuracy of the maintenance signal generated by the processor, the second signal generated by the second photodiode 60 may be compared against the first signal such that changes in the environment, for example the day and night cycle, opening of a window etc. can be accounted for in the generation of the maintenance signal, as these changes in ambient light would be detected by the second photodiode 60. If placed inside the smoke detector the second photodiode 60 can account for deterioration in the equipment, such as the power supply, which may impact the first signal as well as the second signal. The processor would compare the first signal to the second signal and discount changes to the first signal that also occur in the second signal in the generation of the maintenance signal.

[0049] The quality of the maintenance signal can be even further improved with the inclusion of the filter. When using the hygiene sensor module 10 with a light emitting diode it is desirable to absorb all frequencies not emitted by the diode, such that electromagnetic radiation that is not emitted by the light emitting diode, and may not have traversed the mesh 20, is less likely to impact the first signal generated by the photodiode 55.

[0050] The wavelength of light emitted by the light emitting diode may be chosen to increase sensitivity to particulates, greases, etc. likely to occur in a given use case.

[0051] When performing maintenance on the smoke alarm device 100, the cap 30 is also replaced to reset the accumulation of particulates, grease, etc. on the mesh 20. The screw thread 35 allows this replacement to be performed quickly and safely.

[0052] The dimension of the mesh 20 at about 15 mm is an advantageous optimum between size and cost of the hygiene sensor module 10. It is desirable to have a large mesh 20 to accumulate more particulates, grease etc., and for that accumulation to be representative of smoke alarm device 100. However, it is also desirable to have a narrow body 40 to ensure proper

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2019204344 20 Jun 2019 transmission of the ambient light, or emitted light, to the photodiode 55. It is also desirable to produce a small hygiene sensor module 10 to limit material cost.

[0053] The inclusion of multiple hygiene sensor modules 10 provides multiple first signals such that a potentially erroneous signal from a single hygiene sensor module 10 may be compared against the first signal of other hygiene sensor modules 10 and be identified as an erroneous signal.

[0054] Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.

Claims

1. A hygiene sensor module for a smoke alarm device, the sensor module comprising:

a source of electromagnetic radiation;

2. The hygiene sensor module of claim 1, wherein the source of electromagnetic radiation is ambient light.

3. The hygiene sensor module of claim 1 or 2, wherein the source of electromagnetic radiation is a light emitting diode.

4. The hygiene sensor module of claim 3, wherein the light emitting diode emits light in the visible spectrum.

5. The hygiene sensor module of claim 3 or 4, wherein the light emitting diode emits light in the infrared spectrum.

6. The hygiene sensor module of any one of claims 1 to 5, wherein the airflow restrictor and the photodiode are located inside the smoke alarm device

7. The hygiene sensor module of claim 6, wherein the source of electromagnetic radiation is located inside the smoke alarm device.

8. The hygiene sensor module of claim 6 or 7, wherein the smoke alarm device is sealed such that no substantial electromagnetic radiation capable of causing the photodiode to generate a signal enters the smoke alarm device, except for the electromagnetic radiation passing through the airflow restrictor.

9. The hygiene sensor module of any one of claims 1 to 8, wherein a filter is also located between the photodiode and the source of electromagnetic radiation, the filter being adapted to absorb a predetermined portion of the electromagnetic radiation.

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10. The hygiene sensor module of any one of claims 1 to 9, wherein the airflow restrictor is a mesh having a mesh spacing.

11. The hygiene sensor module of claim 10, wherein the mesh is a fibrous material.

12. The hygiene sensor module of claim 11, wherein the fibrous material is wool or glass fibre.

13. The hygiene sensor module of any one of claims 1 to 12, wherein the air flow restrictor is electrostatically active.

14. The hygiene sensor module of any one of claims 1 to 13, wherein the airflow restrictor is mounted in a replaceable cap.

15. The hygiene sensor module of claim 14, wherein the replaceable cap is adapted to be mounted on the smoke alarm device using a thread.

16. The hygiene sensor module of any one of claims 1 to 15, wherein the hygiene sensor module further comprises:

17. The hygiene sensor module of claim 16, wherein the airflow restrictor is not positioned between the second photodiode and the source.

18. The hygiene sensor module of claim 16 or 17, wherein the hygiene sensor module further comprises a second source of electromagnetic radiation, the second source being a light emitting diode, and the second photodiode is adapted to generate the second signal in response to the electromagnetic radiation from the second source.

19. The hygiene sensor module of claim 18, wherein the second source and the second photodiode are located inside the smoke alarm device.

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20. A smoke alarm device having the hygiene sensor module of any one of claims 1 to 19.

21. The smoke alarm device of claim 20, wherein the smoke alarm device has two or more hygiene sensors.

22. The smoke alarm device of claim 20 or 21, wherein the smoke alarm device has a wireless communication module to communicate the maintenance signal to a user device.