Pipeline type liquid level sensor

Abstract

The pipeline type liquid level sensor comprises a water pipe, a shell is connected to the surface of one side of the middle of the water pipe, a PCB is arranged in an inner cavity of the shell, infrared emission lamp beads, infrared receiving lamp beads and triodes are arranged on the PCB, and lamp holders of the infrared emission lamp beads and the infrared receiving lamp beads are obliquely arranged in parallel with the horizontal plane at 45 degrees; a boss is arranged on the connecting face of the water pipe and the shell, the boss is an asymmetric prism, two inclined faces parallel to the lamp holder are arranged on the boss, one end of the triode is connected with the infrared receiving lamp bead, the other end of the triode is connected with the signal line, and the triode achieves reverse level conversion on signals of the infrared receiving lamp bead. The infrared light is received by utilizing whether the infrared light is subjected to secondary reflection in the boss or not, whether water exists in the water pipe or not is judged according to the level output by the signal line, and therefore whether water shortage exists in the water tank or not is monitored in real time, the boss is arranged outside the water pipe, liquid residues are reduced, and the service life of the water tank is prolonged. And incrustation scale or deterioration of edible liquid is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid level sensors, and particularly to a pipeline type liquid level sensor. Background Art

[0002] For current household appliances or industrial equipment with water tanks, it is necessary to monitor in real time whether the water tank is short of water. Among them, detection devices such as floats are used to detect the water level. However, such a structure requires a large amount of space and is difficult to be used in small household appliances or equipment. In addition, when using small-volume pipeline liquid level sensors on the market to detect the water level, a boss is installed inside the water pipe connected to the sensor to act as a prism to detect whether there is liquid. In the case of long-term water flow or other liquids with viscosity, the boss is prone to scale formation, and liquids with reverse viscosity are more likely to adhere to the surface. In particular, foods such as fruit juice and milk will deteriorate. Summary of the Invention

[0003] The purpose of the present invention is to provide a pipeline type liquid level sensor, which uses regular secondary reflection of infrared light in the boss outside the water pipe to realize the reception of infrared light, so as to solve the problems raised in the above background art.

[0004] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0005] A pipeline type liquid level sensor includes a water pipe. The left and right ends of the water pipe are provided with a water inlet end and a water outlet end. The water inlet end of the water pipe is connected to a water tank through a hose, and the water pipe is arranged at the bottom position of the water tank or below the bottom position of the water tank. The water outlet end of the water pipe is connected to a water-using component. One side surface in the middle of the water pipe is connected with a housing. Inside the housing cavity, a PCB board is installed and is vertically opposite to the water pipe. On the inner side surface of the PCB board, there are a transmitting lamp socket, a receiving lamp socket, a triode, and a resistor. An infrared transmitting lamp bead and an infrared receiving lamp bead are respectively installed on the transmitting lamp socket and the receiving lamp socket, and the transmitting lamp socket and the receiving lamp socket are inclined and parallel to the horizontal at 45°. The housing and the water pipe are integrally provided, and the connecting surface material of the water pipe and the housing is an optical medium material. There is a boss on the connecting surface of the water pipe and the housing. The boss is a prism with an asymmetric shape, and its convex surface is arranged inside the housing cavity. There are two parallel inclined surfaces on the boss, and the two inclined surfaces are respectively parallel to the transmitting lamp socket and the receiving lamp socket. Wires are welded on the outer side surface of the PCB board. There are three wires, including two power supply wires and one signal wire. One end of the triode is connected to the infrared receiving lamp bead, and the other end is connected to the signal wire. The triode performs reverse level conversion on the signal of the infrared receiving lamp bead.

[0006] As a further scheme of the present invention: both the water inlet end and the water outlet end of the water pipe are provided with steps, and the water inlet end of the water pipe is connected to the hose through the steps.

[0007] As a further solution of the present invention: two circular convex ribs and a transverse convex rib are provided on the outer ring of the surface of the water pipe far from the outer shell, and the transverse convex rib is arranged between the two circular convex ribs.

[0008] As a further solution of the present invention: the emission lamp socket is arranged in front of the inclined side of the receiving lamp socket.

[0009] As a further solution of the present invention: two longitudinally distributed positioning columns are respectively arranged on the opposite side walls of the inner cavity of the outer shell, and two grooves corresponding to the positioning columns are respectively arranged on the outer surfaces of the two opposite side surfaces of the PCB board.

[0010] As a further solution of the present invention: the two positioning columns are respectively arranged at non-opposite positions on the opposite side walls of the inner cavity of the outer shell, and the two grooves are correspondingly arranged at non-opposite positions on the surfaces of the two opposite side surfaces of the PCB board.

[0011] As a further solution of the present invention: the opening direction of the outer shell is vertically arranged with the water flow direction of the water pipe, a PCB potting adhesive is provided between the outside of the PCB board and the opening in the outer shell, and through holes for the wires to penetrate are opened on the PCB potting adhesive.

[0012] As a further solution of the present invention: the materials of the outer shell and the water pipe are both PCTG-TX1001.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: Through the combination of the convex platform as a prism and the optical medium connection surface, the infrared light of the infrared emission lamp bead vertically passes through an inclined plane, then undergoes regular secondary reflection, and then vertically passes through another inclined plane and is reflected to the infrared receiving lamp bead. The triode performs reverse level conversion on the signal of the infrared receiving lamp bead. That is, when there is liquid passing through the connection section with the housing in the water pipe, the infrared light emitted by the infrared emission lamp bead enters the optical medium connection surface after the first reflection by the convex platform. Since there is liquid on the inner side of the optical medium connection surface, it cannot be reflected to the infrared receiving lamp bead through its second reflection. As a result, the input signal sent by the infrared receiving lamp bead to the triode is a high level, the triode conducts, and the signal output by the signal line is a low level (<0.8V). When there is no liquid passing through the connection section with the housing in the water pipe, the infrared light emitted by the infrared emission lamp bead enters the optical medium connection surface after the first reflection by the convex platform and is reflected to the infrared receiving lamp bead through its second reflection. This makes the input signal of the infrared receiving lamp bead to the triode a low level, the triode cuts off, and the signal output by the signal line is a high level (>2.8V). Thus, by using whether the infrared light undergoes regular secondary reflection in the convex platform to realize the reception of the infrared light and the level of the signal output by the signal line to determine whether there is water in the water pipe, and further to realize the real-time monitoring of whether the water tank is short of water. The structure of this device is simple, does not require much space, is suitable for small household appliances or devices, and the housing and the water pipe are integrally arranged. The convex platform is arranged outside the water pipe, reducing liquid residue and avoiding the generation of water scale or the deterioration of edible liquids. Description of the Drawings

[0014] Figure 1 Stereogram of the pipeline type liquid level sensor of this embodiment.

[0015] Figure 2 Exploded view of the pipeline type liquid level sensor of this embodiment.

[0016] Figure 3 Cross-sectional view of the pipeline type liquid level sensor of this embodiment.

[0017] Figure 4 Structural schematic diagram of the pipeline type liquid level sensor of this embodiment applied to a box body.

[0018] Figure 5 Light ray diagram between the infrared emission lamp bead and the infrared receiving lamp bead in the state where there is liquid in the water pipe of this embodiment.

[0019] Figure 6 Light ray diagram between the infrared emission lamp bead and the infrared receiving lamp bead in the state where there is no liquid in the water pipe of this embodiment.

[0020] Figure 7 Working principle diagram of the pipeline type liquid level sensor of this embodiment.

[0021] Figure 8 This is the circuit schematic diagram of the pipeline type liquid level sensor of this embodiment.

[0022] The reference numerals are: water pipe 1, water inlet end 101, water outlet end 102, connection surface 103, outer shell 2, PCB board 3, infrared emission lamp bead 4, infrared reception lamp bead 5, triode 6, boss 7, inclined surface 701, emission lamp socket 8, reception lamp socket 9, power line 10, signal line 11, step 12, circular rib 13, horizontal rib 14, positioning post 15, groove 16, PCB potting glue 17, water tank 18, water using component 19, hose 20. Specific embodiments

[0023] The following combines the drawings and further describes the specific embodiments of the present invention, making the technical solutions and their beneficial effects of the present invention clearer and more definite.

[0024] As Figures 1 to 8 shown, this embodiment provides a pipeline type liquid level sensor, including a water pipe 1. The left and right ends of the water pipe 1 are provided with a water inlet end 101 and a water outlet end 102. The water inlet end 101 of the water pipe 1 is connected to the water tank 18 through a hose 20, and the water pipe 1 is arranged at the bottom position of the water tank 18 or below the bottom position of the water tank 18. The water outlet end 102 of the water pipe 1 is connected to the water using component 19. One side surface in the middle of the water pipe 1 is connected with an outer shell 2. A PCB board 3 vertically opposite to the water pipe 1 is installed in the inner cavity of the outer shell 2. The inner side surface of the PCB board 3 is provided with an emission lamp socket 8, a reception lamp socket 9, a triode 6 and a resistor (not marked in the figure). An infrared emission lamp bead 4 and an infrared reception lamp bead 5 are respectively installed on the emission lamp socket 8 and the reception lamp socket 9, and the emission lamp socket 8 and the reception lamp socket 9 are arranged in parallel and inclined at 45° to the horizontal. The outer shell 2 and the water pipe 1 are integrally arranged, reducing the risk of water leakage. The material of the connection surface 103 between the water pipe 1 and the outer shell 2 is an optical medium material. A boss 7 is provided on the connection surface 103 between the water pipe 1 and the outer shell 2. The boss 7 is a prism with an asymmetric shape, and its convex surface is arranged in the inner cavity of the outer shell 2. Two parallel inclined surfaces 701 are provided on the boss 7, and the two inclined surfaces 701 are respectively arranged in parallel with the emission lamp socket 8 and the reception lamp socket 9. Wires are welded on the outer side surface of the PCB board 3. There are three wires, including two power lines 10 and one signal line 11. One end of the triode 6 is connected to the infrared reception lamp bead 5, and the other end is connected to the signal line 11. The triode 6 performs reverse level conversion on the signal of the infrared reception lamp bead 5.

[0025] In this embodiment, as Figure 1 and Figure 4 shown, steps 12 are provided at both the water inlet end 101 and the water outlet end 102 of the water pipe 1, and the water inlet end 101 of the water pipe 1 is connected to the hose 20 through the step 12.

[0026] Specifically, the step 12 is provided to prevent the hose 20 from falling off and has better sealing performance with the hose 20.

[0027] In this embodiment, as Figure 1 shown, two circular convex ribs 13 and a transverse convex rib 14 are provided on the outer ring of the surface of the water pipe 1 away from the outer shell 2. The transverse convex rib 14 is arranged between the two circular convex ribs 13 to prevent reflective objects from approaching the water pipe 1 and causing misjudgment.

[0028] In this embodiment, the transmitting lamp socket 8 is arranged in front of the inclined side of the receiving lamp socket 9.

[0029] Specifically, the infrared transmitting lamp beads and the infrared receiving lamp beads are parallel, and the infrared transmitting lamp beads are in front of the infrared receiving lamp beads, avoiding self-interference.

[0030] In this embodiment, as Figure 2 shown, two longitudinally distributed positioning columns 15 are respectively arranged on the opposite side walls of the inner cavity of the outer shell 2, and two grooves 16 corresponding to the positioning columns 15 are respectively arranged on the outer surfaces of the two opposite side surfaces of the PCB board 3.

[0031] Specifically, the two grooves 16 are in interference fit with the two positioning columns 15 to fix and install the PCB board 3 in the outer shell 2, ensuring the emission and reception of infrared light.

[0032] In this embodiment, as Figure 2 and Figure 3 shown, the two positioning columns 15 are respectively arranged at non-opposite positions on the opposite side walls of the inner cavity of the outer shell 2, and the two grooves 16 are correspondingly arranged at non-opposite positions on the two opposite side surfaces of the PCB board 3, so as to achieve anti-fooling during assembly.

[0033] In this embodiment, as Figure 1 shown, the opening direction of the outer shell 2 is vertically arranged with the water flow direction of the water pipe 1. A PCB potting glue 17 is provided between the outer side of the PCB board 3 and the opening in the outer shell 2, and through holes for wire penetration are opened on the PCB potting glue 17.

[0034] Specifically, the setting of the PCB potting glue 17 plays a role in waterproofing and moisture-proofing for the PCB board 3.

[0035] In this embodiment, the materials of the outer shell 2 and the water pipe 1 are both PCTG-TX1001, which does not contain bisphenol A and can be used for the passage of food-grade liquids.

[0036] As Figures 5 to 8 shown, the working principle of the above-mentioned pipeline type liquid level sensor is as follows:

[0037] (1) Power on the PCB board using the power cord (VCC - GND). When there is liquid in the water tank, since the water pipe connected to the water tank is at the bottom position of the water tank or lower than the bottom position of the water tank, the liquid in the water tank flows into the water pipe. After the infrared light emitted by the infrared emitting lamp bead (IR1) vertically passes through the inclined plane of the boss parallel to the emitting lamp socket, it is first reflected by the boss and then enters the optical medium connection surface. Since there is liquid on the inner side of the optical medium connection surface, it cannot make a second reflection to reflect the infrared light to the infrared receiving lamp bead (PT1). The infrared receiving lamp bead (PT1) without receiving infrared light sends an input signal to the triode (Q1). The triode (Q1) performs reverse level conversion to keep the voltage at point A at a high level of 5V, making the triode (Q1) conduct. The voltage at point B output by the triode (Q1) to the signal line (OUT) is at a low level (<0.8V).

[0038] (2) When there is no liquid in the water tank, there is no liquid flowing through the water pipe either. After the infrared light emitted by the infrared emitting lamp bead (IR1) vertically passes through the inclined plane of the boss parallel to the emitting lamp socket, it is first reflected by the boss and then enters the optical medium connection surface. The optical medium connection surface makes a second reflection. The infrared light vertically passes through the inclined plane parallel to the receiving lamp socket and is reflected to the infrared receiving lamp bead (PT1). The infrared receiving lamp bead (PT1) with received infrared light sends an input signal to the triode (Q1). The triode (Q1) performs reverse level conversion to pull down the voltage at point A to a low level (<0.5V), making the triode (Q1) unable to conduct. The voltage at point B output by the triode (Q1) to the signal line (OUT) is at a high level (>2.8V).

[0039] The above is only the preferred specific implementation manner of this embodiment, but the protection scope of this embodiment is not limited thereto. Any person skilled in the art within the technical scope disclosed by this embodiment, according to the technical solution and inventive concept of this embodiment, makes equivalent substitutions or changes, and all should be covered within the protection scope of this embodiment.

Claims

1. A pipeline liquid level sensor, comprising a water pipe (1), characterized in that: The water pipe (1) is provided with a water inlet (101) and a water outlet (102) at both ends. The water inlet (101) of the water pipe (1) is connected to the water tank (18) through a hose (20). The water pipe (1) is arranged at the bottom of the water tank (18) or below the bottom of the water tank (18). The water outlet (102) of the water pipe (1) is connected to a water-using component (19). A shell (2) is connected to the surface of one side in the middle of the water pipe (1). A PCB board (3) arranged vertically opposite to the water pipe (1) is installed in the inner cavity of the shell (2). An emitting lamp holder (8), a receiving lamp holder (9), a triode (6) and a resistor are provided on the inner side of the PCB board (3). Infrared emitting lamp beads (4) and infrared receiving lamp beads (5) are installed on the emitting lamp holder (8) and the receiving lamp holder (9) respectively. The emitting lamp holder (8) and the receiving lamp holder (9) are inclined at 45° with respect to the horizontal. The housing (2) and the water pipe (1) are arranged in parallel, the housing (2) and the water pipe (1) are arranged in an integrated manner, and the material of the connection surface (103) between the water pipe (1) and the housing (2) is an optical medium material. A boss (7) is provided on the connection surface (103) between the water pipe (1) and the housing (2), and the boss (7) is a prism with an asymmetrical shape, and its convex surface is arranged in the inner cavity of the housing (2). Two parallel inclined surfaces (701) are provided on the boss (7), and the two inclined surfaces (701) are respectively arranged in parallel with the transmitting lamp holder (8) and the receiving lamp holder (9). The outer side surface of the PCB board (3) is welded with wires, and the wires have three wires, including two power lines (10) and a signal line (11). One end of the triode (6) is connected to the infrared receiving lamp bead (5), and the other end is connected to the signal line (11), and the triode (6) performs reverse level conversion on the signal of the infrared receiving lamp bead (5).

2. A pipeline liquid level sensor according to claim 1, characterized in that: The water inlet end (101) and the water outlet end (102) of the water pipe (1) are both provided with steps (12), and the water inlet end (101) of the water pipe (1) is connected to the hose (20) via the step (12).

3. A pipeline liquid level sensor according to claim 1, characterized in that: Two circular convex ribs (13) and a transverse convex rib (14) are provided on the outer ring of the surface of the water pipe (1) on the side away from the outer shell (2), and the transverse convex rib (14) is arranged between the two circular convex ribs (13).

4. The pipeline liquid level sensor according to claim 1, characterized in that: The transmitting lamp holder (8) is arranged in front of the inclined side of the receiving lamp holder (9).

5. The pipeline liquid level sensor according to claim 1, characterized in that: Two longitudinally distributed positioning posts (15) are respectively arranged on opposite side walls of the inner cavity of the housing (2), and two grooves (16) corresponding to the positioning posts (15) are respectively arranged on the outer surfaces of two opposite sides of the PCB board (3).

6. A pipeline liquid level sensor according to claim 5, characterized in that: The two positioning posts (15) are respectively arranged at non-opposite positions on opposite side walls of the inner cavity of the housing (2), and the two grooves (16) are correspondingly arranged at non-opposite positions on two opposite side surfaces of the PCB board (3).

7. The pipeline liquid level sensor according to claim 1, characterized in that: The opening direction of the shell (2) is arranged vertically with respect to the water flow direction of the water pipe (1), a PCB potting glue (17) is provided in the shell (2) between the outer side of the PCB board (3) and the opening, and a through hole for a wire to pass through is provided on the PCB potting glue (17).

8. The pipeline liquid level sensor according to claim 1, characterized in that: The materials of the shell (2) and the water pipe (1) are both PCTG-TX1001.

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