Contact type leakage photoelectric sensor

Abstract

The utility model provides a contact type leakage photoelectric sensor, which comprises a shell body, a PCB (printed circuit board) substrate is arranged in the shell body, and a near-infrared light emitting diode, a photosensitive receiving diode and a master control switch circuit are arranged on the PCB substrate. The master control switch circuit is connected with the near-infrared light emitting diode, the photosensitive receiving diode and the control end of the switch tube through ports, the first end of the switch tube is connected with the negative electrode of the power supply, the second end of the switch tube is connected with the positive electrode of the power supply through the pull-up resistor, and the second end of the switch tube is further connected with an external control circuit or an alarm. A lens is arranged at the bottom of the shell body and used for reflecting near-infrared light emitted by the near-infrared light emitting diode to the photosensitive receiving diode. According to the liquid leakage detection device, liquid leakage is detected in an optical mode, so that the accuracy of the liquid leakage detection device cannot be influenced by the purity and the concentration of the liquid and precipitated dirt after the liquid is used for a long time, and the liquid leakage detection device is not easily interfered by the external environment.

Description

TECHNICAL FIELD

[0001] The utility model relates to a liquid leakage detection sensor technical field, specifically is a contact type liquid leakage photoelectric sensor. BACKGROUND

[0002] Liquid leakage sensors are widely used in various scenarios that require detection of liquid leakage, including: industrial production: detecting leaks in pipelines, containers or equipment, and taking timely measures to prevent the leakage from expanding. Automotive engineering: detecting liquid leaks in cars, such as oil, brake fluid, coolant, etc., to ensure the normal operation and safety of the car. Environmental monitoring: detecting water pollution, groundwater leakage, etc., and taking timely measures to prevent environmental deterioration. Security: detecting water leaks in houses and sending out alarms in time to prevent house damage and property loss.

[0003] Currently, capacitive liquid level sensors are commonly used for liquid leakage detection. However, capacitive liquid level sensors use the different capacitance generated by liquid level changes to determine the height of the liquid level. Different water qualities will have different resistance changes. The difference in water quality will directly affect its accuracy, and some liquids cannot be detected. Moreover, the surrounding area of the capacitive liquid level sensor cannot have metal, which is easily disturbed by the external environment, which may cause misoperation, thereby affecting the use or reducing the detection accuracy. SUMMARY

[0004] The purpose of the utility model is to improve and innovate in view of the shortcomings and problems in the background art, and provide a contact type liquid leakage photoelectric sensor.

[0005] A contact type liquid leakage photoelectric sensor, comprising a shell body, a PCB substrate is arranged in the shell body, a near-infrared light-emitting diode, a photosensitive receiving diode and a main control switch circuit are arranged on the PCB substrate, the main control switch circuit is connected with the control end of the near-infrared light-emitting diode, the photosensitive receiving diode and the switching tube through the port, the first end of the switching tube is connected with the negative electrode of the power supply, the second end of the switching tube is connected with the positive electrode of the power supply through the pull-up resistor, the second end of the switching tube is also connected with the external control circuit or the alarm, the shell body bottom is provided with a lens, the lens is used for reflecting the near-infrared light emitted by the near-infrared light-emitting diode to the photosensitive receiving diode, when the liquid submerges the lens, the near-infrared light emitted by the near-infrared light-emitting diode will be refracted into the liquid, which will cause the photosensitive receiving diode to receive little or no light.

[0006] Further, a second TVS tube is connected between the positive electrode and the negative electrode of the power supply.

[0007] Further, a first TVS tube is connected between the first end and the second end of the switching tube.

[0008] Further, the switch tube can be an NPN triode or an N-type MOS tube.

[0009] Further, the master control switch circuit is connected with the control end of the switch tube through an action indicator.

[0010] Further, a black light shield is arranged on the PCB substrate, and the black light shield is used to separate the near-infrared light emitting diode and the light-sensitive receiving diode.

[0011] Further, the outer surface of the shell body is provided with a body connecting portion, a first limiting groove is formed in the body connecting portion, a body buckle is clamped in the first limiting groove through the body connecting portion, and a body buckle connecting portion matched with the first limiting groove is arranged on the body buckle.

[0012] Further, the outer surface of the shell body is provided with a wire outlet sleeve connecting portion for wire outlet, a wire outlet sleeve clamping block is arranged on the outer surface of the wire outlet sleeve connecting portion, a wire outlet sleeve is inserted into the inner wall of the wire outlet sleeve connecting portion, a wire outlet sleeve buckle is arranged on the outer surface of the wire outlet sleeve connecting portion and the wire outlet sleeve, and a second limiting groove matched with the wire outlet sleeve clamping block is formed in the wire outlet sleeve buckle.

[0013] Compared with the prior art, the contact type liquid leakage photoelectric sensor has the advantages that: the liquid leakage photoelectric sensor utilizes the principle of reflection and refraction of light at the interface of two different media. When the lens of the sensor is immersed in liquid, the light is refracted into the liquid, and the light received by the receiver is reduced or changed. When there is no liquid, the light is directly reflected from the lens to the light-sensitive receiving diode. By sensing the change, the sensor can determine whether the liquid exists. Since the existence of liquid leakage is detected by using the optical method, the purity, concentration and long-term use sediment dirt of the liquid will not affect the accuracy of the sensor. Moreover, the liquid leakage photoelectric sensor has great advantages in the installation structure of the machine water tank, and can be installed in any direction. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0015] Fig. 1 The circuit principle diagram of the contact type liquid leakage photoelectric sensor provided by the embodiments of the present application;

[0016] Fig. 2A contact type liquid leakage photoelectric sensor structure schematic diagram (not including the shell cover plate) is provided in the embodiment of the utility model.

[0017] Fig. 3 A contact type liquid leakage photoelectric sensor explosion structure schematic diagram is provided in the embodiment of the utility model.

[0018] The figure mark: 1, the shell cover plate;2, the PCB substrate;3, the black light shield;4, the shell body;401, the body connecting part;402, the first limit slot;403, the outgoing line sleeve connecting part;404, the outgoing line sleeve clamping block;5, the outgoing line sleeve;6, the outgoing line sleeve buckle;601, the second limit slot;7, the body buckle;701, the body buckle connecting part;8, the support;9, the near infrared light emitting diode;10, the photosensitive receiving diode;11, the main control switch circuit;12, the diode;13, the action indicator lamp;14, the fuse;15, the pull-up resistor;16, the switch tube;17, the first TVS tube;18, the second TVS tube. DETAILED DESCRIPTION

[0019] In order to make the purpose, features and advantages of the utility model more obvious and easy to understand, the specific implementation of the utility model is described in detail below with reference to the drawings.

[0020] It should be noted that when an element is referred to as being "fixed" to another element, it can be directly on the other element or there can be intervening elements. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements can be present.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the utility model belongs. The terminology used in the description of the utility model herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0022] Please refer to Figs. 1-3 The utility model provides a kind of contact type liquid leakage photoelectric sensor, including shell body 4, shell body 4 is installed with support, the shell body 4 is also provided with PCB substrate 2, PCB substrate 2 is placed on support, the quantity of support is preferably three, so that support can stably support PCB substrate 2. Shell body 4 upper end is covered with shell cover plate 1, shell body 4 and shell cover plate 1 are pressed together by ultrasonic welding.

[0023] The outer surface of the shell body 4 is provided with a body connecting part 401 and a wire outlet sleeve connecting part 403 which are integrally formed with the shell body 4. The body connecting part 401 is provided with a first limiting groove 402, and the body connecting part 401 is clamped with a body buckle 7 through the first limiting groove 402. The middle part of the body buckle 7 is provided with a body buckle connecting part 701 which cooperates with the first limiting groove 402, and the body buckle connecting part 701 is symmetrically arranged on the body buckle 7. During the process that the body buckle connecting part 701 passes through the first limiting groove 402, the two body buckle connecting parts 701 are deformed under the extrusion of the inner wall of the first limiting groove 402, so that the two body buckle connecting parts 701 are close to each other and pass through the first limiting groove 402. After the body buckle connecting part 701 passes through the first limiting groove 402, the body buckle connecting part 701 returns to the original state, so as to clamp the body connecting part 401 on the body buckle 7. In addition, the both ends of the body buckle 7 are provided with through holes for the screw to pass through, so as to facilitate the installation of the body buckle 7 in the place to be detected by the screw.

[0024] The outer surface of the shell body 4 is also provided with a wire outlet sleeve connecting part 403 for wire outlet, and the outer surface of the wire outlet sleeve connecting part 403 is provided with a wire outlet sleeve clamping block 404. The wire outlet sleeve 5 is inserted into the inner wall of the wire outlet sleeve connecting part 403, and the diameter of the wire outlet sleeve 5 is smaller than that of the wire outlet sleeve connecting part 403. The power line of the external circuit or alarm device extends to the inside of the shell body 4 and is connected with the PCB substrate 2 after passing through the wire outlet sleeve 5. The outer surface of the wire outlet sleeve connecting part 403 and the wire outlet sleeve 5 is integrally provided with a wire outlet sleeve buckle 6, and the wire outlet sleeve buckle 6 is provided with a second limiting groove 601 which cooperates with the wire outlet sleeve clamping block 404. By clamping the wire outlet sleeve buckle 6 on the wire outlet sleeve connecting part 403, the wire outlet sleeve connecting part 403 and the wire outlet sleeve 5 can be fixed together.

[0025] The PCB substrate 2 is provided with a near-infrared light emitting diode 9, a light-sensitive receiving diode 10 and a master control switch circuit 11. Generally, the light-sensitive receiving diode 10 works under reverse voltage, that is, the cathode of the light-sensitive receiving diode 10 is connected to the positive pole of the power supply. When there is no light, the reverse current of the light-sensitive receiving diode 10 is very small, and at this time the light-sensitive receiving diode 10 is equivalent to an open circuit. When there is light, the photo-generated carriers increase significantly, resulting in a significant increase in reverse current, and at this time the light-sensitive receiving diode 10 is turned on. The master control switch circuit 11 is connected to the cathode of the near-infrared light emitting diode 9, the anode of the light-sensitive receiving diode 10 and the control end of the switching tube 16 through the port. The first end of the switching tube 16 is connected to the negative pole of the power supply, the second end of the switching tube 16 is connected to the positive pole of the power supply through the pull-up resistor 15, and the second end of the switching tube 16 is also connected to an external control circuit or an alarm. The PCB substrate 2 is also provided with a black light shield 3, which is used to separate the near-infrared light emitting diode 9 and the light-sensitive receiving diode 10, so as to avoid the near-infrared light emitted by the near-infrared light emitting diode 9 directly acting on the light-sensitive receiving diode 10. The bottom of the shell body 4 is provided with a lens, which is not shown in the figure, and the lens is used to reflect the near-infrared light emitted by the near-infrared light emitting diode 9 to the light-sensitive receiving diode 10, at this time the light-sensitive receiving diode 10 is turned on; when liquid leakage occurs, the liquid will enter the inside of the shell body 4 through the through hole opened at the bottom end of the shell body 4, so that the liquid will slowly immerse the lens, and the near-infrared light emitted by the near-infrared light emitting diode 9 will be refracted into the liquid, resulting in that the light-sensitive receiving diode 10 cannot receive or receives a small amount of light, at this time the light-sensitive receiving diode 10 is turned off. When the light-sensitive receiving diode 10 is turned on, the master control switch circuit 11 outputs a high level to the control end of the switching tube 16, so that the switching tube 16 is turned on, at this time the voltage of the second end of the switching tube 16 is pulled down to a low level, at this time the external control circuit or the alarm connected to the second end of the switching tube 16 will not act; when the light-sensitive receiving diode 10 is turned off, the master control switch circuit 11 outputs a low level to the control end of the switching tube 16, at this time the switching tube 16 will not be turned on, at this time the voltage of the second end of the switching tube 16 is pulled up to a high level, at this time the external control circuit or the alarm connected to the second end of the switching tube 16 will act, and execute alarm or other protection measures.

[0026] It should be noted that in the present embodiment, the switching tube 16 can be an NPN triode or an N-type MOS tube, and the present application does not make specific limitations. When the switching tube 16 is an NPN triode, the base of the triode is connected to the master control switch circuit 11, the emitter of the triode is connected to the negative pole of the power supply, and the collector of the triode is connected to the positive pole of the power supply through the pull-up resistor 15; when the switching tube 16 is an N-type MOS tube, the gate of the N-type MOS tube is connected to the master control switch circuit 11, the source of the N-type MOS tube is connected to the negative pole of the power supply, and the drain of the N-type MOS tube is connected to the positive pole of the power supply.

[0027] It should be further explained that in the present embodiment, the main control switch circuit 11 can comprise another NPN type transistor, the base of which is connected with the anode of the light-sensitive receiving diode 10, the collector of which is connected with the positive pole of the power supply, and the emitter of which is connected with the control end of the switch tube 16.

[0028] Preferably, a second TVS tube 17 is connected between the positive pole and the negative pole of the power supply, and a first TVS tube 18 is connected between the first end and the second end of the switch tube 16. The TVS tube is also known as transient voltage suppression diode, and its working principle is to maintain a high resistance state, equivalent to an open circuit, when the circuit is working normally, without affecting the normal operation of the circuit. However, once an abnormal overvoltage appears in the circuit, exceeding the breakdown voltage of the TVS tube, it will quickly change from a high resistance state to a low resistance state, leading the overcurrent to the ground, thereby protecting the subsequent circuit from damage. When the abnormal overvoltage disappears, the TVS tube will automatically restore to a high resistance state, ensuring the stability and safety of the circuit. When an overvoltage appears between the positive pole and the negative pole of the power supply, the current flows through the first TVS tube 18, and when an overvoltage appears between the collector and the emitter of the switch tube 16, the current flows through the second TVS tube 17; so that the second TVS tube 17 and the first TVS tube 18 have the function of absorbing instantaneous surge, and play the role of protecting the switch tube 16.

[0029] Preferably, the main control switch circuit 11 is connected with the control end of the switch tube 16 through the action indicating lamp 13, and according to the on-off of the action indicating lamp 13, it can be judged whether the switch tube 16 is turned on or not.

[0030] Preferably, the collector of the switch tube 16 is connected with the external circuit or the alarm through the fuse 14, which can avoid the excessive current flowing into the external circuit or the alarm.

[0031] Preferably, the main control switch circuit 11 is connected with the positive pole of the power supply through the diode 12, which will not be turned on when the positive pole and the negative pole of the power supply are reversely connected, so that the circuit has the function of power reverse connection.

[0032] In conclusion, the contact type liquid leakage photoelectric sensor is provided, and the liquid leakage photoelectric sensor utilizes the principle that light is reflected and refracted at the interface of two different mediums. When the lens of the sensor is immersed in liquid, the light is refracted into the liquid, and the light received by the receiver is reduced or changed. When there is no liquid, the light is directly reflected from the lens to the light-sensitive receiving diode 10. By sensing the change, the sensor can determine whether the liquid exists. Since the existence of the liquid leakage is detected by using the optical method, the purity, concentration and long-term use sediment dirt of the liquid will not affect the accuracy of the sensor. Moreover, the liquid leakage photoelectric sensor has great advantages in the installation structure of the machine water tank, and can be installed in any direction.

[0033] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0034] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "illustrative embodiment", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example.

[0035] Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. In this article, "embodiments" means that the specific features, structures or characteristics described in connection with the embodiments can be contained in at least one embodiment of the present application. The appearance of this phrase at various places in the specification is not necessarily all the same embodiments, nor is it independent or alternative to other embodiments. It can be explicitly or implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application. Although the embodiments of the present application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and purposes of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A contact leak light photo sensor, characterized by: The application relates to a liquid immersion detection device, which comprises a shell body (4) provided with a PCB substrate (2) inside, a near-infrared light emitting diode (9), a light-sensitive receiving diode (10) and a main control switch circuit (11) arranged on the PCB substrate (2), the main control switch circuit (11) is connected with the near-infrared light emitting diode (9), the light-sensitive receiving diode (10) and the control end of a switch tube (16) through a port, the first end of the switch tube (16) is connected with the negative pole of a power supply, the second end of the switch tube (16) is connected with the positive pole of the power supply through an upper pull resistor (15), the second end of the switch tube (16) is also connected with an external control circuit or an alarm, the bottom of the shell body (4) is provided with a lens, the lens is used for reflecting the near-infrared light emitted by the near-infrared light emitting diode (9) to the light-sensitive receiving diode (10); when the lens is immersed in liquid, the near-infrared light emitted by the near-infrared light emitting diode (9) is refracted into the liquid, so that the light-sensitive receiving diode (10) cannot receive or receives a small amount of light.

2. A contact leak light photo sensor according to claim 1, wherein: The positive pole of the power supply and the negative pole of the power supply are connected with a second TVS tube (17).

3. A contact leakage optical photosensor according to claim 1, wherein: The first end and the second end of the switch tube (16) are connected with a first TVS tube (18).

4. The contact leak light photo sensor according to claim 1, wherein: The switch tube (16) can be an NPN type triode or an N type MOS tube.

5. A contact leakage optical photosensor according to claim 1, wherein: The main control switch circuit (11) is connected with the control end of the switch tube (16) through an action indicating lamp (13).

6. A contact leakage optical photosensor according to claim 1, wherein: The PCB substrate (2) is also provided with a black light shielding sheet (3) for separating the near-infrared light emitting diode (9) and the light-sensitive receiving diode (10).

7. The contact leakage optical photosensor according to claim 1, wherein: The outer surface of the shell body (4) is provided with a body connecting part (401), the body connecting part (401) is provided with a first limiting groove (402), the body connecting part (401) is clamped with a body buckle (7) through the first limiting groove (402), and the body buckle (7) is provided with a body buckle connecting part (701) matched with the first limiting groove (402).

8. The contact leak light photo sensor according to claim 1, wherein: The outer surface of the shell body (4) is also provided with a wire outlet sleeve connecting part (403) for wire outlet, the wire outlet sleeve connecting part (403) is provided with a wire outlet sleeve clamping block (404), a wire outlet sleeve (5) is inserted into the inner wall of the wire outlet sleeve connecting part (403), and the outer surfaces of the wire outlet sleeve connecting part (403) and the wire outlet sleeve (5) are sleeved with a wire outlet sleeve buckle (6), and the wire outlet sleeve buckle (6) is provided with a second limiting groove (601) matched with the wire outlet sleeve clamping block (404).

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