Immersion sensor based on photoelectric detection principle

Abstract

The invention discloses an immersion sensor based on a photoelectric detection principle. The immersion sensor comprises a connector, an upper cover, a flange plate, a gasket, a light-emitting sensing circuit, a light reflection cone, an inner shell and an outer shell, the luminous sensing circuit is provided with an infrared transmitting tube, an infrared transmitting tube driving module, a light receiving tube, a power supply module and a signal processing module; the connector can connect an external power supply with the power supply module. The sensor can be installed at a specific position of an airplane, and the airplane can rapidly contact with a water body when accidentally falling into the water. When the sensor probe is not in contact with a water body, light emitted by the infrared emitting tube is totally reflected at the probe part, the intensity of light received by the photoelectric receiving tube is the highest, when the sensor probe is in contact with the water body, the light emitted by the infrared emitting tube is partially refracted at the probe part, and a light intensity signal received by the photoelectric receiving tube is reduced; and the immersion detection can be completed by using the intensity change of the received light.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft protection and life-saving, and relates to a water immersion sensor based on the photoelectric detection principle. Background Art

[0002] A water sensor is a device that detects the presence of water or liquid. It is widely used in helicopter crash alarms, detecting water ingress to ships and floating facilities, and preventing accidents. The existing water sensors mainly involve the following aspects.

[0003] Conductivity sensor: Utilizes the conductivity of water to determine whether water is present by detecting changes in the current in the circuit. The conductivity of water will reduce the resistance between the two electrodes, causing a change in the current.

[0004] Capacitive sensor: determines the presence of water by detecting changes in capacitance. When water contacts the sensor, it changes the capacitance between the sensor electrodes, triggering an alarm.

[0005] Ultrasonic sensor: detects water level through the reflection of ultrasonic waves and changes in the propagation speed. The presence of water will change the propagation characteristics of ultrasonic waves, and the sensor makes judgments based on this change.

[0006] The above sensors have the advantages of simple wiring and low cost, and are widely used in a wide range of applications. However, they may cause false alarms due to water mist during use and have certain limitations. Therefore, in response to the above problems, the present invention provides a water immersion sensor based on the photoelectric detection principle. Summary of the invention

[0007] The purpose of the present invention is to provide a water immersion sensor based on the photoelectric detection principle, which can determine whether the device to which it belongs has fallen into water from the air and give a related switch signal.

[0008] The technical solution of the present invention is:

[0009] Provided is a water immersion sensor based on the photoelectric detection principle, comprising a connector 1, an upper cover 2, a flange 3, a gasket 4, a light-emitting sensing circuit 5, a light-reflecting cone 6, an inner shell 7 and an outer shell 8; the light-emitting sensing circuit 5 has an infrared transmitting tube 9, an infrared transmitting tube driving module, a light receiving tube 10 (photosensitive diode), a power module and a signal processing module; the connector can connect an external power supply to the power module;

[0010] The connector is fixedly connected to the upper cover, the upper cover is fixedly and sealedly connected to the flange, the inner ring of the flange forms a cavity, the upper cover is sealed and fixed to the upper opening of the cavity, the gasket 4 is arranged in the cavity, the gasket 4 is used to fix the light-emitting sensing module 5 in the inner cavity, the light-reflecting cone 6 is sealed and fixed to the lower opening of the cavity, the tip of the light-reflecting cone 6 faces outward, and the infrared emitting tube 9 and the photosensitive diode 10 are symmetrically arranged about the rotation axis of the light-reflecting cone, and the light emitted by the infrared emitting tube 9 can be reflected in the conical surface of the light-reflecting cone. The light is refracted into a concave shape and irradiated to the light receiving tube 10. The light receiving tube 10 senses the changes in the intensity of the light. The signal processing module generates an electrical signal and outputs it through the connector. When there is water on the outer surface of the light reflecting cone, it will be partially refracted. Therefore, the light intensity reflected in the water and water-free states will be different. The flange is fixedly and sealedly connected with the inner shell. The inner shell 7 and the opening under the flange are sealed and fixed to surround the light cone. A through hole is opened at the bottom of the inner shell. The inner shell is fixedly and sealedly connected to the outer shell outside, so that a gap is formed between the outer shell and the inner shell. A through hole is opened at the bottom of the outer shell.

[0011] Furthermore, the gasket 4 is made of plastic.

[0012] Furthermore, the through holes at the bottom of the outer shell and the through holes at the bottom of the inner shell are staggered in position.

[0013] Furthermore, the connector is fixedly connected to the upper cover by means of a cross hexagonal screw.

[0014] Furthermore, the upper cover is connected to the upper opening of the cavity of the flange by laser welding.

[0015] Furthermore, a circular connection hole is formed on the flange, so as to facilitate installation at a specific position of the aircraft. Furthermore, there are multiple washers, and the luminous sensing module 5 is clamped between the multiple washers.

[0016] Furthermore, the light receiving tube 10 is a photosensitive diode.

[0017] Furthermore, the inner shell and the outer shell are connected via threads.

[0018] Furthermore, the inner shell is threadedly connected to the flange.

[0019] The material selection of the light-reflecting cone can be used to calculate the refractive index range of the cone material according to the principle. It is known that the incident angle θ1 is 45 degrees, and θ2 is 90 degrees when total reflection occurs. Assuming the refractive index of the probe medium is n, the refractive index is 1.33 when the outside is water, and the refractive index is about 1 when the outside is air. It is calculated that the refractive index of total reflection when there is no water outside is about 1.414, that is, the refractive index of the probe should be greater than 1.414. Similarly, it can be calculated that when there is water outside, partial refraction occurs at this time, and the refractive index should be less than 1.885. Comprehensive analysis shows that the refractive index of the probe is between 1.414 and 1.885. Materials that meet this range can be used as probes using a cone with a 45-degree inclination angle.

[0020] The through holes of the inner shell and the outer shell are staggered to prevent a small amount of water and water mist from entering the cavity of the inner shell and causing false alarms.

[0021] The photoelectric effect of the light receiving diode converts the received light signal into a current signal. The current passing through the photodiode increases with the intensity of the light it receives, and the voltage comparator generates a final output voltage signal. When the output voltage is at a low level, it is in a non-water immersion state; when the voltage is at a high level, it is in a water immersion alarm state, thereby realizing the alarm control of water immersion.

[0022] The present invention also discloses an assembly process of a water immersion sensor based on the photoelectric detection principle, which specifically includes the following steps:

[0023] S1. Insert the light reflecting cone and the plastic gasket into the inner cavity of the flange in turn, seal them with glue, and then dry them. There are two holes in the lower opening of the flange. Place the light emitting diode and the light receiving diode in the two holes in the lower opening of the flange, place the circuit on the plastic gasket, and perform glue filling and drying.

[0024] S2. Fit the inner shell with the flange through threads, rotate the inner shell to the bottom and slightly adjust it so that its lower opening is flush with the limit block placement platform, place the limit block, and tighten it with screws.

[0025] S3. Apply thread glue to the inner and outer threads of the outer shell, screw them as deep as possible, and stagger the openings of the inner and outer shells, and wait for the thread glue to solidify.

[0026] S4. Connect the upper cover and the flange by laser welding.

[0027] S5. Align the connector with the outside of the upper cover and tighten it with screws.

[0028] The advantages of the present invention are: the present invention uses the principle of refraction and reflection of light in different medium cross sections and the photoelectric effect for detection, and is not affected by the properties of the test medium. Through the optimization design of optical materials and structures, the influence of environmental natural light and water mist is eliminated, and the sensor test accuracy is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the structure of the present invention;

[0030] Figure 2 It is a schematic diagram of the structure of the flange;

[0031] Figure 3 It is a schematic diagram of the structure of the inner and outer shells;

[0032] Figure 4 It is the optical path principle diagram of the present invention;

[0033] Figure 5 It is the circuit schematic diagram of the luminescence sensing circuit;

[0034] Figure 6 It is a cross-sectional view of the structure of the present invention;

[0035] In the figure: 1 is a connector, 2 is an upper cover, 3 is a flange, 4 is a plastic gasket, 5 is a light sensing circuit, 6 is a light reflecting cone, 7 is an inner shell, 8 is an outer shell, 9 is a light emitting tube, and 10 is a light receiving diode. DETAILED DESCRIPTION

[0036] The disclosed examples will be more fully described with reference to the accompanying drawings, in which some (but not all) of the disclosed examples are shown. In fact, many different examples may be described and these examples should not be construed as limited to the examples set forth herein. Instead, these examples are described so that this disclosure will be thorough and complete and will fully convey the scope of the disclosure to those skilled in the art.

[0037] Provided is a water immersion sensor based on the photoelectric detection principle, comprising a connector 1, an upper cover 2, a flange 3, a gasket 4, a light-emitting sensing circuit 5, a light-reflecting cone 6, an inner shell 7 and an outer shell 8; the light-emitting sensing circuit 5 has an infrared transmitting tube 9, an infrared transmitting tube driving module, a light receiving tube 10 (photosensitive diode), a power module and a signal processing module; the connector can connect an external power supply to the power module;

[0038] The connector is fixedly connected to the upper cover, the upper cover is fixedly and sealedly connected to the flange, the inner ring of the flange forms a cavity, the upper cover is sealed and fixed to the upper opening of the cavity, the gasket 4 is arranged in the cavity, the gasket 4 is used to fix the light-emitting sensing module 5 in the inner cavity, the light-reflecting cone 6 is sealed and fixed to the lower opening of the cavity, the tip of the light-reflecting cone 6 faces outward, and the infrared emitting tube 9 and the photosensitive diode 10 are symmetrically arranged about the rotation axis of the light-reflecting cone, and the light emitted by the infrared emitting tube 9 can be reflected in the conical surface of the light-reflecting cone. The light is refracted into a concave shape and irradiated to the light receiving tube 10. The light receiving tube 10 senses the changes in the intensity of the light. The signal processing module generates an electrical signal and outputs it through the connector. When there is water on the outer surface of the light reflecting cone, it will be partially refracted. Therefore, the light intensity reflected in the water and water-free states will be different. The flange is fixedly and sealedly connected with the inner shell. The inner shell 7 and the opening under the flange are sealed and fixed to surround the light cone. A through hole is opened at the bottom of the inner shell. The inner shell is fixedly and sealedly connected to the outer shell outside, so that a gap is formed between the outer shell and the inner shell. A through hole is opened at the bottom of the outer shell.

[0039] The gasket 4 is made of plastic.

[0040] The through hole at the bottom of the outer shell and the through hole at the bottom of the inner shell are staggered in position.

[0041] The connector is fixedly connected to the upper cover by a cross hexagonal screw.

[0042] The upper cover is connected to the cavity upper opening of the flange by laser welding.

[0043] The flange is provided with a circular connection hole, which is convenient for installation at a specific position of the aircraft. Furthermore, there are multiple washers, and the luminous sensing module 5 is clamped between the washers, and glue is poured into the cavity to fix it.

[0044] The light receiving tube 10 is a photosensitive diode.

[0045] Furthermore, the inner shell and the outer shell are connected via threads.

[0046] The inner shell is threadedly connected to the flange.

[0047] The description of different advantageous arrangements has been presented for purposes of illustration and description, but the description is not intended to be exclusive or limited to examples of the disclosed form. Many modifications and variations will be apparent to those of ordinary skill in the art. Additionally, different advantageous examples may describe different advantages over other advantageous examples. The selected example or examples are chosen and described in order to best illustrate the principles of the examples, the practical application, and to enable those of ordinary skill in the art to understand the disclosure with various examples with various modifications suitable for the particular use contemplated.

Claims

1. A water immersion sensor based on the principle of photoelectric detection, characterized in that: It includes a connector, an upper cover, a flange, a gasket, a light-emitting sensing circuit, a light-reflecting cone, an inner shell and an outer shell; the light-emitting sensing circuit has an infrared emitting tube, an infrared emitting tube driving module, a light receiving tube, a power module and a signal processing module; the connector can connect the external power supply to the power module; The connector is fixedly connected to the upper cover, and the upper cover is fixedly and sealedly connected to the flange. The inner ring of the flange forms a cavity, and the upper cover is sealed and fixed to the upper opening of the cavity. The gasket is arranged in the cavity, and the gasket is used to fix the light sensing module in the inner cavity. The light reflecting cone is sealed and fixed to the lower opening of the cavity, and the tip of the light reflecting cone faces outward, and the infrared emitting tube and the photosensitive diode are symmetrically arranged about the rotation axis of the light reflecting cone. The light emitted by the infrared emitting tube can form a concave refraction on the cone surface of the light reflecting cone and irradiate the light receiving tube. The light receiving tube senses the intensity change of the light, and the signal processing module generates an electrical signal and outputs it through the connector. When there is water on the outer surface of the light reflecting cone, it will be partially refracted, so that the light intensity reflected in the water and water-free state is different; the flange is fixedly and sealedly connected to the inner shell, and the inner shell and the lower opening of the flange are sealed and fixed to surround the light cone. A through hole is opened at the bottom of the inner shell, and the inner shell is fixedly and sealedly connected to the outer shell outside, so that a gap is formed between the outer shell and the inner shell, and a through hole is opened at the bottom of the outer shell.

2. A water immersion sensor based on the photoelectric detection principle according to claim 1, characterized in that: The gasket is made of plastic.

3. The water immersion sensor based on the photoelectric detection principle according to claim 1 is characterized in that: The through hole at the bottom of the outer shell and the through hole at the bottom of the inner shell are staggered in position.

4. The water immersion sensor based on the photoelectric detection principle according to claim 1 is characterized in that: The connector is fixedly connected to the upper cover by a cross hexagonal screw.

5. The water immersion sensor based on the photoelectric detection principle according to claim 1 is characterized in that: The upper cover is connected to the cavity upper opening of the flange by laser welding.

6. The water immersion sensor based on the photoelectric detection principle according to claim 1, characterized in that: A circular connecting hole is formed on the flange.

7. The water immersion sensor based on the photoelectric detection principle according to claim 1 is characterized in that: There are multiple washers, and the luminous sensing module is clamped between the multiple washers.

8. The water immersion sensor based on the photoelectric detection principle according to claim 1, characterized in that: The light receiving tube is a photosensitive diode.

9. The water immersion sensor based on the photoelectric detection principle according to claim 1, characterized in that: The inner shell is connected to the outer shell by threads.

10. The water immersion sensor based on the photoelectric detection principle according to claim 1, characterized in that: The inner shell is threadedly connected to the flange.

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