A container liquid level sensor

Abstract

The present application relates to the technical field of sensor, specifically to a kind of container liquid residual amount sensor, including support, cavity structure and the joint structure for being connected with container;Support is equipped with vent hole, the upper portion of vent hole is equipped with pressure sensor sheet, pressure sensor sheet is installed in cavity structure, the edge of cavity structure is sealed with support, cavity structure is equipped with gas guide rod, gas guide rod is axially equipped with the through hole being communicated with cavity structure, the beneficial technical effects of the present application are: 1, capacity sensor small, easy to install, low to installation space requirement;2, accurate measurement, not affected by altitude pressure, less affected by normal inclination of vehicle.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sensors, in particular to a container liquid residual amount sensor. BACKGROUND

[0002] The oil level sensor for vehicle mainly provides the fuel tank oil amount information for the driver, so as to facilitate the driver to timely fill fuel, prevent the vehicle from stopping halfway due to fuel exhaustion, and can also be used for detecting various liquids and non-corrosive chemical reagent tanks, and displaying the liquid level information through the instrument.

[0003] The common fuel tank oil level sensor for vehicle generally adopts the structure of slide wire variable resistor and thick-thin resistor, and its principle is that the float in the fuel tank floats up and down with the oil amount, drives the float rod contact to change the slide wire variable resistor resistance value, under the condition of fixed load voltage, the output current changes, and the current value is directly reflected on the combination instrument through the hardware circuit. Due to the frequent sliding of the contact, short circuit, open circuit, poor contact and mechanical wear and other faults are prone to occur. In addition, in order to measure the oil amount, the length of the float rod is generally equivalent to the depth of the fuel tank, so the volume is large, which affects the real oil amount of the fuel tank on the one hand, and the float itself has a certain thickness, which will cause the limited float travel, when the oil amount is large, the float reaches the maximum travel, and the oil amount above the float cannot be accurately measured. Secondly, the above situation is only applicable to the fuel tank with regular shape, and sometimes the fuel tank is designed to be irregular in cooperation with the vehicle body during the vehicle body design. Due to the installation space limitation of the float rod, the part below the float also cannot measure the remaining oil amount through the float, thereby affecting the judgment of the driver on the oil amount.

[0004] Therefore, it is necessary to develop a new type of oil amount detection device. SUMMARY

[0005] In order to solve the problems of large volume, easy failure due to wear, short circuit and inaccurate oil amount measurement of the float type oil level sensor in the prior art, a container liquid residual amount sensor is provided, which has the characteristics of small volume, low failure rate and accurate measurement.

[0006] In order to achieve the above purpose, the following technical scheme is provided:

[0007] A container liquid residual amount sensor, comprising a pressure sensor sheet, a support of the pressure sensor sheet, a cavity structure and a joint structure for connecting with the container; the support is provided with a vent hole, the pressure sensor sheet is arranged at the upper part of the vent hole, the pressure sensor sheet is installed in the cavity structure, the edge of the cavity structure is sealed with the support, the cavity structure is provided with a gas guide rod, the gas guide rod is axially provided with a through hole communicating with the cavity structure, and the pin wire of the pressure sensor sheet passes through the support downward under the condition of isolation between the cavity structure and the bottom of the support.

[0008] Preferably, a diaphragm is arranged between the through hole of the air guide rod and the cavity structure.

[0009] Preferably, an air pressure tube is sleeved on the air guide rod, the top of the air pressure tube is sealed, and the bottom of the air pressure tube is provided with an air channel communicating with the top of the through hole.

[0010] Preferably, the air pressure tube is in a cylindrical shape or is curved in at least two of the horizontal, vertical and inclined directions.

[0011] Preferably, the lower part of the support member is provided with a cylinder, and the lower part of the air hole is communicated with a pressure guide pipe.

[0012] Preferably, the lower part of the cavity structure is provided with a cylinder, and the lower part of the air hole is communicated with a pressure guide pipe.

[0013] Preferably, the cylinder is filled with a sealing material, and the bottom end of the pressure guide pipe extends out of the sealing material.

[0014] Preferably, the inner wall of the cylinder is provided with a recess or a protrusion.

[0015] Preferably, the joint structure is a connecting cylinder with an internal thread or an external thread on the support member.

[0016] Preferably, the joint structure is a connecting cylinder with an internal thread or an external thread on the cavity structure.

[0017] The use and working principle of the present application are as follows: as a matching oil tank of the sensor, the oil tank can be pre-punched at the bottom when leaving the factory, the capacity sensor is connected with the bottom of the oil tank through the joint structure, so that the oil in the oil tank can be in contact with the through hole, and the top of the through hole is preferably flush with the lowest part of the oil tank cavity. The pressure sensor sheet comprises a support member and a silicon diaphragm located in the middle of the support member, and a resistance bridge is etched on the silicon diaphragm. When the silicon diaphragm is subjected to pressure, the resistance bridge will produce stress deformation, resulting in resistance change, so that the voltage applied to the resistance changes, and the signal change is fed back to the controller through the pin line. The controller converts the signal into the corresponding weight through the program, and displays the capacity of the oil in the oil tank after conversion on the instrument panel. Compared with the float type oil level sensor, there is no wear and short circuit, so the failure rate is low.

[0018] The vent at the bottom of the support unit is connected to atmospheric pressure. When the tank is empty, the pressure inside the tank detected by the pressure sensor (the tank cap has a vent connecting to the atmosphere) is balanced with the atmospheric pressure on the other side of the pressure sensor, and the pressure sensor detects zero pressure. When there is oil in the tank, the oil enters the cavity structure through the through hole at the top of the air guide rod, generating pressure on the pressure sensor and causing it to deform. This deformation is caused by the pressure difference between the sum of the oil weight, the atmospheric pressure connected to the tank cap, and the atmospheric pressure on the other side of the pressure sensor. The voltage change generated by the pressure sensor is transmitted to the controller through the pin wire. The controller calculates the oil mass in the tank according to the program, and then calculates the corresponding oil volume according to the oil density and the capacity of different tanks, and displays the oil level on the instrument panel.

[0019] In this solution, since the atmospheric pressure inside the fuel tank cancels out the atmospheric pressure at the bottom of the pressure sensor during detection, only the fuel level inside the tank is measured. This means that the fuel level can be accurately measured even when the vehicle is located at high or low altitudes. When the vehicle is driving or parked on a non-level surface such as a slope or curb, and is in a normal tilted state, although the angle of the fuel level may increase or decrease, the impact on the pressure change on the pressure sensor is small, and the impact on the measurement results is also small.

[0020] The beneficial technical effects of this invention are: 1. The capacity sensor is small in size, easy to install, requires little installation space, and has a low failure rate; 2. The measurement is accurate, unaffected by altitude and air pressure, and is minimally affected when the vehicle is in a normal tilted state; 3. It can be used for liquid level detection in fuel tanks, water tanks, oil tanks, various industrial liquids, and reagent boxes. Attached Figure Description

[0021] Appendix Figure 1 This is a schematic diagram of one structure of the container liquid balance sensor in this invention;

[0022] Appendix Figure 2 This is a structural cross-sectional view of the container liquid balance sensor in this invention;

[0023] Appendix Figure 3 for Figure 2 Explosion-proof diagram of the structure;

[0024] Appendix Figure 4 This is another structural cross-sectional view of the container liquid balance sensor in this invention;

[0025] Appendix Figure 5 for Figure 4 Explosion-proof diagram of the structure;

[0026] Appendix Figure 6A schematic view of a connector structure of a container liquid residual amount sensor in the present application;

[0027] A Figure 7 A schematic view of another connector structure of a container liquid residual amount sensor in the present application;

[0028] A Figure 8 A schematic view of an assembly of a container liquid residual amount sensor in the present application;

[0029] A Figure 9 A schematic view of another assembly of a container liquid residual amount sensor in the present application;

[0030] In the figure: 1, support; 2, air hole; 3, pressure sensor sheet; 4, cavity structure; 5, air guide rod; 6, through hole; 7, cylinder; 8, pressure guide tube; 9, sealing material; 10, recess; 11, air pressure tube; 12, connecting cylinder; 13, fastening nut; 14, cutting surface; 15, bottom cover; 16, pin wire; 17, oil tank; 18, sealing ring; 19, sealing gasket. DETAILED DESCRIPTION

[0031] The container liquid residual amount sensor in the present application is further described below in combination with the drawings and specific embodiments.

[0032] As Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 indicated, a container liquid residual amount sensor includes a pressure sensor sheet 3, a support 1 of the pressure sensor sheet, a cavity structure 4, and a connector structure for connecting with a container; the support 1 is provided with an air hole 2, the pressure sensor sheet 3 is arranged at the upper part of the air hole 2, the pressure sensor sheet 3 is installed in the cavity structure 4, the edge of the cavity structure 4 is sealed with the support 1, the cavity structure 4 is provided with a through hole 6 communicating with the cavity structure 4, the through hole 6 is communicated with an air guide rod 5 with an axial air hole, and the pin wire of the pressure sensor sheet 3 passes through the support 1 downward under the condition of being isolated between the cavity structure 4 and the bottom of the support 1.

[0033] As Figure 8 , Figure 9As shown, as the matching tank 17 of the sensor, the tank 17 can be pre-punched at the bottom when it leaves the factory, and the capacity sensor is connected to the bottom of the tank 17 through a joint structure, so that the oil in the tank 17 can contact the air guide rod 5, and the top of the air guide rod 5 is preferably flush with the lowest part of the inner cavity of the tank 17. The pressure sensor sheet 3 includes a support 1 and a silicon diaphragm in the middle of the support 1. Specifically, an annular frame is arranged on the upper part of the support 1, the silicon diaphragm is arranged on the annular frame, and the annular frame is integrally formed with the support 1. The silicon diaphragm is etched with a resistance bridge. When the silicon diaphragm is subjected to pressure, the resistance bridge will produce stress deformation, resulting in resistance change, so that the voltage applied to the resistance changes, and the signal change is fed back to the controller through the pin line 16. The controller converts the signal into the corresponding weight through the program, and displays the capacity of the oil in the tank 17 after conversion on the instrument panel.

[0034] If the tank is regular in shape, the oil mass can be directly converted into oil volume and displayed on the instrument panel. If the tank is irregular in shape, the oil mass can be converted into oil volume through calibration.

[0035] The air hole 2 at the bottom of the support 1 is connected to the atmospheric pressure. When the tank 17 is empty, the pressure detected by the pressure sensor sheet 3 inside the tank 17 (with the air hole connected to the atmosphere) is balanced with the atmospheric pressure on the other side of the pressure sensor sheet 3, and the pressure detected by the pressure sensor sheet 3 is zero. When the tank 17 has oil, the oil enters the cavity structure 4 from the through hole 6 at the top of the air guide rod 5, which generates pressure on the pressure sensor sheet 3, causing the pressure sensor sheet 3 to deform. The deformation is caused by the pressure difference between the sum of the oil weight and the connected atmospheric pressure and the atmospheric pressure on the other side of the pressure sensor sheet 3. The voltage change generated by the pressure sensor sheet 3 is transmitted to the controller through the pin line 16. The controller calculates the oil mass in the tank 17 according to the program, and calculates the corresponding oil volume according to the oil density and the capacity of different tanks 17 and displays the oil quantity on the instrument panel.

[0036] Compared to traditional pressure sensors that measure container capacity, traditional pressure sensors, due to their sealed bottom and the presence of air (assuming atmospheric pressure), suffer from errors. In high-altitude regions with lower atmospheric pressure, the pressure at the sensor's bottom is significantly higher, creating a pressure difference that can lead to inaccuracies in the measured liquid volume. If used with fuel tank 17, this could affect the driver's judgment of fuel level. In this solution, however, the atmospheric pressure inside fuel tank 17 cancels out the atmospheric pressure at the bottom of the pressure sensor 3 during detection. Therefore, it only measures the fuel volume, unaffected by altitudes, ensuring accurate fuel level measurement. When the vehicle is traveling on or stationary on slopes or curbs, the angle of the fuel level may change, but this has minimal impact on the pressure change on the sensor and the measurement result. Furthermore, the duration of this tilt is short, making the effect negligible.

[0037] In one embodiment, a diaphragm is provided between the through hole 6 of the air guide rod 5 and the cavity structure 4, which is not shown in the figure.

[0038] The diaphragm can be made of corrosion-resistant material, allowing it to measure various industrial liquids and corrosive chemical reagents. The diaphragm is secured between the through-hole 6 of the air guide rod 5 and the cavity structure 4 by a retaining ring, sealing air between the diaphragm and the cavity structure 4. The function of the diaphragm is as follows: when oil enters the air guide rod 5, it exerts pressure on the diaphragm, causing it to deform and compress the air inside the cavity structure 4. The air inside the cavity structure 4 then compresses and deforms the pressure sensor plate 3. When the vehicle is located at high or low altitudes, because the inside of the fuel tank 17 is connected to the atmosphere, and the bottom of the pressure sensor plate 3 is also connected to the atmosphere, the two air pressures cancel each other out, thus the air sealed between the diaphragm and the cavity structure 4 is not affected by altitude.

[0039] like Figure 3 , Figure 5 As shown, a pressure pipe 11 is fitted onto the air guide rod 5. The top of the pressure pipe 11 is sealed, and an air passage with a connecting hole 6 is provided between the bottom of the pressure pipe 11 and the top of the air guide rod 5. The pressure pipe 11 is rigidly connected to the air guide rod 5 and is directly and securely fitted.

[0040] When the container sensor is installed to the bottom of the empty oil tank 17, there is air in the air channel between the bottom of the air pressure pipe 11 and the top of the communication hole 6 of the air guide rod 5. When the oil tank 17 is filled with oil, the air in the air channel will be sealed. As the oil level increases, the oil will inevitably enter the air channel for a short distance. Because the specific gravity of the oil is lighter than the pressure of the air sealed in the air channel, the oil will not directly enter the communication hole 6 of the air guide rod 5. Instead, the oil will push the air in the air channel, which will act on the pressure sensor sheet 3 and then squeeze the pressure sensor sheet 3. When the vehicle is in a high-altitude or low-altitude area, the pressure sensor sheet 3 is connected to the atmosphere at the bottom, and the two air pressures balance, so the air sealed in the air channel is not affected by the altitude.

[0041] The air pressure pipe 11 can be cylindrical or curved in at least two of the horizontal, vertical, and inclined directions.

[0042] As shown in Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , the air pressure pipe 11 is cylindrical, and the side of the air pressure pipe 11 is longitudinally provided with a cut surface 14, so that there is a gap between the air pressure pipe 11 and the air guide rod 5, and the oil in the oil tank 17 can communicate with the air in the air guide rod 5 through the gap.

[0043] As shown in Figure 8 , in this embodiment, the air pressure pipe 11 is horizontally placed in a spiral shape, as shown in Figure 9 , in this embodiment, the air pressure pipe 11 is curved in two horizontal and inclined directions. Because driving will encounter uphill, downhill, vehicle collision with obstacles, and other situations, the spiral shape or the shape curved in at least two of the horizontal, vertical, and inclined directions can ensure that the air in the air channel will not escape from the oil in the above situations, and the air will be maximized.

[0044] As shown in Figure 4 , Figure 5 , in this embodiment, the lower part of the support 1 is provided with a cylinder 7, and the lower part of the air hole 2 is communicated with a pressure guide pipe 8. The cylinder 7 is filled with a sealing material 9, and the bottom end of the pressure guide pipe 8 extends out of the sealing material 9.

[0045] The cylinder 7 is used to protect the bottom structure of the pressure sensor sheet 3 and to fill the sealing material 9. The pressure conducting pipe 8 is extended as the air hole 2 at the bottom to communicate with the atmosphere. The pin wire 16 is led downward through the support 1. In the case of isolation sealing between the cavity structure and the bottom of the support 1, the pin wire 16 can be led downward through an additional hole in the support 1. In order to avoid the pin wire 16 from falling off, the sealing material 9 is used to seal the pin wire 16 in the cylinder 7. In this embodiment, the sealing material 9 is resin. The sealing material 9 is used to protect the pin wire 16 and the pressure conducting pipe 8 from damage and falling off caused by vibration.

[0046] In this embodiment, after the pressure sensor sheet 3 is installed on the support 1, the cavity structure 4 is sealed and connected with the support 1 by welding. This is a one-time consumable.

[0047] As shown in Figure 2 , Figure 3 , in this embodiment, the cylinder 7 is arranged at the lower part of the cavity structure 4, and the pressure conducting pipe 8 is communicated with the air hole 2 below the support 1. The cylinder 7 is filled with the sealing material 9, and the bottom end of the pressure conducting pipe 8 is extended out of the sealing material 9.

[0048] The cylinder 7 is used to protect the bottom structure of the pressure sensor sheet 3 and to fill the sealing material 9. The pressure conducting pipe 8 is extended as the air hole 2 at the bottom. The pin wire of the pressure sensor sheet is led downward. In order to avoid the pin wire 16 from falling off, the sealing material 9 is used to seal the pin wire 16 in the cylinder 7. In this embodiment, the sealing material 9 is resin. The sealing material 9 is used to protect the pin wire 16 and the pressure conducting pipe 8 from damage and falling off caused by vibration.

[0049] As shown in Figure 2 , in this embodiment, the sealing ring 18 is sleeved on the annular support periphery of the pressure sensor sheet 3. When the support 1 with the pressure conducting pipe 8 is inserted from below the cylinder 7, the sealing ring 18 is clamped with the inner hole wall of the cavity structure 4 to achieve temporary fixation. Then the sealing material 9 is poured into the cylinder 7. The sealing ring 18 can be used for temporary fixation and sealing between the support 1 and the inner wall of the cavity structure 4, and can also prevent the sealing material from entering the pressure sensor sheet.

[0050] As shown in Figure 2 , Figure 4 , the inner wall of the cylinder 7 is provided with a recess 10 or a protrusion. When the sealing material 9 seals the cylinder 7, the recess 10 or the protrusion can be tightly connected with the sealing material 9 to avoid the sealing material 9 from falling off.

[0051] As shown in Figure 5 , Figure 6As shown, the lower part of the support 1 is provided with a cylinder 7, and the lower part of the air hole 2 is connected with a pressure guide pipe 8. The joint structure is a threaded connecting cylinder 12 on the support 1.

[0052] When the joint structure is the threaded connecting cylinder 12 on the support 1, a hole is formed in the bottom of the corresponding oil tank 17, and an externally threaded connecting pipe is installed outside the hole. The threaded connecting cylinder 12 is screwed with the externally threaded connecting pipe, and a sealing ring 18 is arranged inside the threaded connecting cylinder 12. When the joint structure is the externally threaded connecting cylinder 12 on the support 1, the connecting cylinder 12 is inserted into the hole and is fixed inside the oil tank 17 by a nut.

[0053] In other embodiments, as shown in Figure 4 , Figure 5 , the joint structure is a fastening nut 13 sleeved on the support 1, and a sealing ring 18 is arranged inside the fastening nut 13. A hole is formed in the bottom of the corresponding oil tank 17, and an externally threaded connecting pipe is installed outside the hole. The fastening nut 13 is screwed with the externally threaded connecting pipe, and the volume sensor can be kept stationary while the fastening nut 13 is screwed.

[0054] As shown in Figure 2 , Figure 3 , in this embodiment, the lower part of the cavity structure 4 is provided with a cylinder 7, and the lower part of the air hole 2 of the support 1 is connected with a pressure guide pipe 8. The joint structure is a threaded connecting cylinder 12 on the cavity structure 4.

[0055] When the joint structure is the threaded connecting cylinder 12 on the cavity structure 4, a hole is formed in the bottom of the corresponding oil tank 17, and an externally threaded connecting pipe is installed outside the hole. The threaded connecting cylinder 12 is screwed with the externally threaded connecting pipe, and a sealing ring 18 is arranged inside the threaded connecting cylinder 12. When the joint structure is the externally threaded connecting cylinder 12 on the cavity structure 4, the connecting cylinder 12 is inserted into the hole and is fixed inside the oil tank 17 by a nut.

[0056] In other embodiments, as shown in Figure 2 , Figure 3 , the joint structure is a fastening nut 13 sleeved on the cavity structure 4, and a sealing ring 18 is arranged inside the fastening nut 13. A hole is formed in the bottom of the corresponding oil tank 17, and an externally threaded connecting pipe is installed outside the hole. The fastening nut 13 is screwed with the externally threaded connecting pipe, and the volume sensor can be kept stationary while the fastening nut 13 is screwed, and the top of the air guide rod 5 is inserted into the externally threaded connecting pipe, and it is appropriate that the lowest end of the cavity of the oil tank 17 is flush.

[0057] As shown in Figure 2 , Figure 3 , Figure 4 , Figure 5As shown, the bottom cover 15 is sleeved on the bottom of the barrel 7. The bottom cover 15 is provided with air holes, and is used to reduce dust and other sundries from entering the barrel 7.

Claims

1. A container liquid level sensor, characterized by, The pressure sensor sheet (3), the support (1) of the pressure sensor sheet, the cavity structure (4), and the joint structure for connecting with the container are included; the support (1) is provided with a vent hole (2), the pressure sensor sheet (3) is arranged on the upper part of the vent hole (2), the pressure sensor sheet (3) is installed in the cavity structure (4), the edge of the cavity structure (4) is sealed with the support (1), the cavity structure (4) is provided with a gas guide rod (5), the gas guide rod (5) is axially provided with a through hole (6) communicating with the cavity structure (4), the pin wire of the pressure sensor sheet (3) passes through the support (1) downward under the condition that the cavity structure (4) and the support (1) bottom are isolated, the gas pressure pipe (11) is sleeved on the gas guide rod (5), the top of the gas pressure pipe (11) is sealed, the gas pressure pipe (11) bottom is provided with a gas channel communicating with the top of the through hole (6) between the gas guide rod (5); the gas pressure pipe (11) is cylindrical or curved in at least two directions of horizontal, vertical and inclined, the side of the gas pressure pipe (11) is longitudinally provided with a tangent plane (14), so that a gap is left between the gas pressure pipe (11) and the gas guide rod (5).

2. The container liquid level sensor as described in claim 1, characterized in that, The through hole (6) of the gas guide rod (5) and the cavity structure (4) are provided with a diaphragm.

3. The container fluid level sensor of claim 1 or 2, wherein, The lower part of the support (1) is provided with a cylinder (7), and the lower part of the vent hole (2) is communicated with a pressure conducting pipe (8).

4. The container fluid level sensor of claim 3, wherein, The cylinder (7) is filled with a sealing material (9), and the bottom end of the pressure conducting pipe (8) extends out of the sealing material (9).

5. The container fluid level sensor of claim 3, wherein, The inner wall of the cylinder (7) is provided with a recess (10) or a protruding part.

6. The container fluid level sensor of claim 4, wherein, The inner wall of the cylinder (7) is provided with a recess (10) or a protruding part.

Images