CN216524236U - Liquid leakage type liquid level sensor - Google Patents
Liquid leakage type liquid level sensor Download PDFInfo
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- CN216524236U CN216524236U CN202123011832.8U CN202123011832U CN216524236U CN 216524236 U CN216524236 U CN 216524236U CN 202123011832 U CN202123011832 U CN 202123011832U CN 216524236 U CN216524236 U CN 216524236U
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Abstract
The utility model relates to a liquid leakage type liquid level sensor, which comprises an upper cover, an indicator light, a sealing screw, a sealing ring, a lower cover and a circuit unit, wherein the upper cover is provided with a liquid inlet and a liquid outlet; the upper cover and the lower cover are embedded and connected by adopting a concave-convex groove, and the indicator light and the sealing screw are arranged on the upper part of the upper cover; the bottom of the lower cover is provided with a supporting base; the circuit unit is arranged in a cavity formed by the upper cover and the lower cover; the circuit unit comprises an induction capacitor, an oscillation circuit, an F/V conversion circuit, a signal processing unit, an output unit, a potentiometer, an indicating unit and a power circuit; the induction capacitor, the oscillating circuit, the F/V conversion circuit, the signal processing unit and the output unit are electrically connected in sequence; the output end of the potentiometer is electrically connected with the signal processing unit, and the input end of the indicating unit is electrically connected with the signal processing unit; the oscillation circuit adopts a crystal oscillator. Through the arrangement, the problems that the conventional capacitive liquid level sensor cannot normally work at high temperature and cannot give an alarm in time when the bin level is full can be solved.
Description
Technical Field
The utility model relates to the technical field of instruments and meters, in particular to a liquid leakage type liquid level sensor.
Background
In a traditional capacitance type liquid level sensor (switch), an induction capacitor is connected in series in an RC oscillation loop; when the power supply is switched on, the RC oscillator does not oscillate; when a target approaches towards the electrodes of the capacitor, the capacitance of the capacitor increases and the oscillator starts to oscillate. The vibration and oscillation signals are converted into switching signals through the processing of a post-stage circuit, so that the purpose of detecting whether an object exists is achieved.
However, the general capacitive proximity switches can only work at the industrial temperature of-25 ℃ to 70 ℃; when the temperature rises above 70 ℃, the amplitude of the RC oscillation changes and the sensing distance decreases accordingly.
Meanwhile, the working environment of the existing capacitive liquid level sensor (switch) is mostly that the internal environment is detected in the container; when the bin is full, the measured object overflows or flows over the induction surface in the production process, the alarm cannot be given in time, and the loss and the accident in the production process can be caused.
SUMMERY OF THE UTILITY MODEL
In order to solve the above technical problems, an object of the present invention is to provide a liquid leakage type liquid level sensor, so as to solve the problems that the existing capacitive liquid level sensor cannot normally operate at a high temperature and cannot give an alarm in time when the bin level is full.
In order to achieve one of the above objectives of the present invention, an embodiment of the present invention provides a liquid leakage level sensor, which includes an upper cover, an indicator light, a sealing screw, a sealing ring, a lower cover, and a circuit unit; the upper cover and the lower cover are connected in an embedded mode through concave-convex grooves, the sealing ring is arranged between the upper cover and the lower cover, and the indicator light and the sealing screw are arranged on the upper portion of the upper cover; the bottom of the lower cover is provided with a supporting base; the circuit unit is arranged in a cavity formed by the upper cover and the lower cover;
the circuit unit comprises an induction capacitor, an oscillation circuit, an F/V conversion circuit, a signal processing unit, an output unit, a potentiometer, an indicating unit and a power circuit; the induction capacitor, the oscillating circuit, the F/V conversion circuit, the signal processing unit and the output unit are electrically connected in sequence; the output end of the potentiometer is electrically connected with the signal processing unit, and the input end of the indicating unit is electrically connected with the signal processing unit; the output end of the power supply circuit is electrically connected with the oscillating circuit, the F/V conversion circuit, the signal processing unit and the output unit respectively; the oscillation circuit adopts a crystal oscillator.
As a further improvement of an embodiment of the present invention, the sensing capacitor is a double-sided circular circuit board with a shield.
As a further improvement of an embodiment of the present invention, the potentiometer is a multi-turn potentiometer for adjusting sensitivity.
As a further improvement of an embodiment of the present invention, the indicator light is an LED status indicator light.
As a further improvement of an embodiment of the utility model, the power supply circuit comprises an anti-reverse connection double diode, a stabilized voltage power supply and a power supply chip; the voltage-stabilizing power supply comprises an 18V voltage-stabilizing tube and a triode which are electrically connected with each other; the stabilized voltage power supply is electrically connected with the power supply chip; the output pin of the power chip is connected with a high-capacity tantalum capacitor in parallel and used for voltage stabilization and filtering and providing stable +5V power supply.
As a further improvement of an embodiment of the present invention, the F/V conversion circuit employs a multi-channel gating chip using the crystal oscillator as a signal source.
As a further improvement of an embodiment of the present invention, the signal processing unit includes a hysteresis comparator circuit employing a single power supply, high bandwidth, rail-to-rail operational amplifier; the in-phase end of the operational amplifier is electrically connected with the output end of the F/V conversion circuit, and the inverting end of the operational amplifier is electrically connected with a fixed reference voltage pin.
As a further improvement of an embodiment of the present invention, the potentiometer includes an adjusting knob for adjusting a magnitude of a voltage signal at a non-inverting terminal of the operational amplifier.
As a further improvement of an embodiment of the present invention, the output unit includes an output control element, a self-recovery fuse; the output control element adopts a triode; the self-recovery fuse is arranged at the output end of the output unit.
As a further improvement of an embodiment of the present invention, the leakage liquid level sensor further includes a resistance guide rod; the lower end of the resistance guide rod is connected with the potentiometer, and the upper end of the resistance guide rod is connected with the sealing screw; the support base comprises 3 annular face domain structures; and a pattern drawing angle structure is arranged on the upper cover and/or the lower cover.
Compared with the prior art, the utility model has the beneficial effects that:
the liquid leakage type liquid level sensor is provided with an upper cover, an indicator light, a sealing screw, a sealing ring, a lower cover and a circuit unit;
the circuit unit is arranged in a cavity formed by the upper cover and the lower cover and is used for detecting the material bin level or the liquid level;
the circuit unit is provided with an induction capacitor, an oscillation circuit, an F/V conversion circuit, a signal processing unit, an output unit, a potentiometer, an indicating unit and a power circuit; the oscillation circuit adopts a crystal oscillator with high precision, low temperature drift and good temperature stability, can stably work in a high-temperature environment, and has a large working temperature range, so that the detection stability can be greatly improved;
meanwhile, when the liquid leakage type liquid level sensor is arranged on the top of the bin or the side wall of the bin body, the bottom of the lower cover of the liquid leakage type liquid level sensor is provided with a supporting base, so that a certain distance exists between the sensing surface and the bin body to be measured; when the material to be measured flows through the space, an output signal is generated in time; therefore, when the bin is full or the materials overflow, the material level or the liquid level can be accurately monitored so as to alarm in time.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the embodiments or the description of the prior art will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the utility model, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.
FIG. 1 is a schematic diagram of a leaky level sensor in an embodiment of the utility model;
FIG. 2 is a cross-sectional block diagram of a weep level sensor in an embodiment of the present invention;
FIG. 3 is a block circuit diagram of a leaky level sensor in an embodiment of the utility model.
Wherein the reference numbers referred to in the figures are as follows:
the device comprises an upper cover 1, a resistor guide rod 11, an indicator light 12, a sealing screw 13, a lower cover 2, a circuit unit 3 and a sealing ring 4.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail and completely with reference to the following detailed description of the utility model and the accompanying drawings. It is to be understood that the described embodiments are merely exemplary of the utility model, and not restrictive of the full scope of the utility model. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.
As shown in fig. 1 to 2, an embodiment of the present invention provides a leakage liquid level sensor, which includes an upper cover 1, an indicator light 12, a sealing screw 13, a sealing ring 4, a lower cover 2, and a circuit unit 3; the upper cover 1 and the lower cover 2 are embedded and connected by adopting a concave-convex groove, the sealing ring 4 is arranged between the upper cover 1 and the lower cover 2, and the indicator light 12 and the sealing screw 13 are both arranged at the upper part of the upper cover 1; the bottom of the lower cover 2 is provided with a supporting base; the circuit unit 3 is arranged in a cavity formed by the upper cover 1 and the lower cover 2;
the circuit unit 3 comprises an induction capacitor, an oscillating circuit, an F/V conversion circuit, a signal processing unit, an output unit, a potentiometer, an indicating unit and a power circuit; the induction capacitor, the oscillating circuit, the F/V conversion circuit, the signal processing unit and the output unit are electrically connected in sequence; the output end of the potentiometer is electrically connected with the signal processing unit, and the input end of the indicating unit is electrically connected with the signal processing unit; the output end of the power supply circuit is respectively and electrically connected with the oscillating circuit, the F/V conversion circuit, the signal processing unit and the output unit; the oscillation circuit adopts a crystal oscillator.
Specifically, the liquid type liquid level sensor is provided with an upper cover 1, an indicator light 12, a sealing screw 13, a sealing ring 4, a lower cover 2 and a circuit unit 3;
the circuit unit 3 is arranged in a cavity formed by the upper cover 1 and the lower cover 2 and is used for detecting the material bin level or the liquid level;
the circuit unit 3 is provided with an induction capacitor, an oscillation circuit, an F/V conversion circuit, a signal processing unit, an output unit, a potentiometer, an indicating unit and a power circuit; the oscillation circuit adopts a crystal oscillator with high precision, low temperature drift and good temperature stability, can stably work in a high-temperature environment, and has a large working temperature range, so that the detection stability can be greatly improved;
meanwhile, when the liquid leakage type liquid level sensor is arranged on the top of the bin or the side wall of the bin body, the bottom of the lower cover 2 is provided with a supporting base, so that a certain distance exists between the sensing surface and the bin body to be measured; when the material to be measured flows through the space, an output signal is generated in time; therefore, when the bin is full or the materials overflow, the material level or the liquid level can be accurately monitored so as to alarm in time.
In practical use, the liquid leakage type liquid level sensor has a large working temperature range and can stably work in a high-temperature environment; meanwhile, the device can be used on the top of the bin or the side wall of the bin body, and can give an alarm in time when a measured object in the bin overflows or flows over the induction surface, so that the loss in the production process is reduced.
Therefore, the following beneficial effects are achieved:
the device has the advantages of high reliability, accurate detection precision, no temperature influence, high temperature resistance, strong anti-interference capability, simple structure, low cost, convenient maintenance, small volume and attractive appearance, and can measure detected objects with various dielectric constants;
when the measured object in the storage bin overflows or flows over the induction surface, the alarm can be given in time, and the loss in the production process is reduced.
Furthermore, the induction capacitor is a double-sided circular shielding circuit board.
Therefore, the induction precision can be improved, and the anti-interference capability can be enhanced.
In practical use, the double-sided circular shielding circuit board with the shielding tape has good anti-interference capability and excellent sensing capability.
Further, the potentiometer is a multi-turn potentiometer and is used for adjusting the sensitivity.
Thus, the object to be detected having various dielectric constants can be detected.
Further, the indicator light 12 is an LED status indicator light.
Therefore, the display device can be used for displaying the state of the switch signal and can intuitively know the output state.
Furthermore, the power supply circuit comprises an anti-reverse connection double diode, a voltage-stabilized power supply and a power supply chip; the stabilized voltage power supply comprises an 18V voltage stabilizing tube and a triode which are electrically connected with each other; the stabilized voltage power supply is electrically connected with the power supply chip; the output pin of the power chip is connected in parallel with a high-capacity tantalum capacitor for voltage stabilization and filtering and providing stable +5V power supply.
In practical use, the double diodes are adopted to prevent reverse short circuit, so that the circuit can be effectively protected, and the power supply is more stable;
the power supply part is a voltage stabilizing circuit matched with the triode through an 18V voltage stabilizing tube, and the voltage within the power supply range is stabilized and then sent into the power supply chip.
After the power chip is subjected to voltage reduction, the +5V voltage is generated after filtering and voltage stabilization, and the stable voltage is provided for various components such as an oscillating circuit, an F/V conversion unit, a signal processing unit and an output unit, so that good and stable working voltage is ensured.
Furthermore, the F/V conversion circuit adopts a multi-channel gating chip which takes a crystal oscillator as a signal source.
In actual use, the sensing capacitance detected on the sensing capacitance is transmitted to the F/V changing unit through the oscillating circuit. The F/V change unit is a multi-channel gating chip, the inductive capacitor is continuously charged and discharged through an oscillation signal provided by the oscillation circuit, the inductive capacitor changed along with an inductive object is changed into voltage changed on the inductive capacitor, and therefore the process of changing a capacitance signal into a voltage signal is completed. Meanwhile, the F/V change unit transmits the changed voltage signal to the signal processing unit.
Further, the signal processing unit comprises a hysteresis comparator circuit which adopts a single power supply, a high bandwidth, and a rail-to-rail operational amplifier; the non-inverting terminal of the operational amplifier is electrically connected with the output terminal of the F/V conversion circuit, and the inverting terminal of the operational amplifier is electrically connected with the fixed reference voltage pin.
Further, the potentiometer comprises an adjusting knob for adjusting the magnitude of the voltage signal at the non-inverting terminal of the operational amplifier.
In practical use, the signal processing unit adopts a single-power-supply, high-bandwidth, rail-to-rail operational amplifier. The F/V conversion circuit inputs signals to the in-phase end of the operational amplifier, the inverting end of the operational amplifier is connected with a fixed reference voltage pin, and a hysteresis comparator circuit is formed according to the connection mode of the amplifier;
meanwhile, the same-phase end voltage signal transmitted to the signal processing unit by the F/V is controlled by the potentiometer, and the size of the same-phase end voltage signal can be changed and the sensitivity can be controlled by adjusting a knob of the potentiometer, so that the product can detect detected objects with various dielectric constants. The in-phase terminal voltage is compared with the reverse-phase terminal voltage of the operational amplifier, and a switching value signal is output to the output unit according to the comparison result.
Further, the output unit comprises an output control element and a self-recovery fuse; the output control element adopts a triode; the self-recovery fuse is arranged at the output end of the output unit.
In actual operation, the switching value signal output by the signal processing unit is transmitted to the output unit, and the output unit adopts a triode with large bearing current as an output control element; meanwhile, the output end is also provided with a self-recovery fuse, when the output part is in short circuit, the self-recovery fuse can cut off an output loop in time, so that the output part is protected; when the short circuit condition disappears, the self-recovery fuse can be conducted again, so that the output is recovered to be normal.
As shown in fig. 3, in the specific embodiment, the operation principle of the circuit part is as follows:
the power supply part is used for stabilizing the voltage in the power supply range and then sending the voltage into a power supply chip through a voltage stabilizing circuit matched with an 18V voltage stabilizing tube and a triode.
The power supply chip generates +5V voltage after voltage reduction and filtering and stabilizing, and provides stable voltage for various components such as an oscillating circuit, an F/V conversion unit, a signal processing unit, an output unit and the like, thereby ensuring good working environment.
Meanwhile, the power supply part has an anti-reverse diode, so that the circuit can be effectively protected.
The induction capacitor is a double-sided circular shielding circuit board with a shielding function, and has good anti-interference capability and excellent induction capability.
The oscillating circuit provides the sensed condition after the sensing capacitor is connected to the oscillating circuit. The oscillation circuit adopts the crystal oscillator with high precision, low temperature drift and good temperature stability, and does not use the oscillation circuit formed by combining separate elements such as RC, LC and the like which are greatly influenced by temperature to provide oscillation signals, so that the temperature stability is improved, stable oscillation frequency can be provided at different temperatures, and the performance is stable.
The sensing capacitance detected by the sensing capacitance is transmitted to the F/V changing unit through the oscillating circuit. The F/V change unit is a multi-channel gating chip, the inductive capacitor is continuously charged and discharged through an oscillation signal provided by the oscillation circuit, the inductive capacitor changed along with an inductive object is changed into voltage changed on the inductive capacitor, and therefore the process of changing a capacitance signal into a voltage signal is completed. Meanwhile, the F/V change unit transmits the voltage signal after the change is transmitted to the signal processing unit.
The signal processing unit adopts a single power supply, high bandwidth and rail-to-rail operational amplifier. The F/V conversion circuit inputs signals to the in-phase end of the operational amplifier, the inverting end of the operational amplifier is connected with a fixed reference voltage pin, and a hysteresis comparator circuit is formed according to the connection mode of the amplifier;
meanwhile, the same-phase end voltage signal transmitted to the signal processing unit by the F/V is controlled by the potentiometer, and the size of the same-phase end voltage signal can be changed and the sensitivity can be controlled by adjusting a knob of the potentiometer, so that the product can detect detected objects with various dielectric constants. The in-phase terminal voltage is compared with the reverse-phase terminal voltage of the operational amplifier, and a switching value signal is output to the output unit according to the comparison result.
Meanwhile, the indicating unit is provided with an LED state indicating lamp, and the change of the color is controlled by the switching value signal of the signal processing unit to indicate the output state, so that an operator can observe the LED state indicating lamp more intuitively.
Finally, the switching value signal output by the signal processing unit is transmitted to an output unit, and the output unit adopts a triode with large bearing current as an output control element; meanwhile, the output end is also provided with a self-recovery fuse, when the output part is in short circuit, the self-recovery fuse can cut off an output loop in time, so that the output part is protected; when the short circuit condition disappears, the self-recovery fuse can be conducted again, so that the output is recovered to be normal.
Furthermore, the leakage liquid level sensor also comprises a resistance guide rod 11; the lower end of the resistance guide rod 11 is connected with a potentiometer, and the upper end is connected with a sealing screw 13; the support base comprises 3 annular surface structures; the upper cover 1 and/or the lower cover 2 are/is provided with a pattern drawing angle structure.
In practical use, the upper part of the upper cover 1 is provided with an indicator lamp 12, a resistance guide rod 11 and a screw 13; the indicator lamp 1 is an LED status indicator lamp and is used for displaying the status of a switch signal;
the lower part of the resistance guide rod 11 is connected with a potentiometer, and the upper part of the resistance guide rod 11 is connected with a screw 13; under the condition of not using a potentiometer, the locking screw 13 is waterproof and dustproof, and meanwhile, the error adjustment operation is avoided;
the lower part of the upper cover 1 is also provided with 3 annular surface areas for stabilizing the product and making the product not easy to incline and overturn.
Upper cover 1 and lower cover 2 adopt tongue and groove embedding design, and the joint makes both closely cooperate through the draft angle, and built-in have sealing washer 4, waterproof dustproof.
It should be understood that although the present description refers to embodiments, not every embodiment contains only a single technical solution, and such description is for clarity only, and those skilled in the art should make the description as a whole, and the technical solutions in the embodiments can also be combined appropriately to form other embodiments understood by those skilled in the art.
The above-listed detailed description is only a specific description of a possible embodiment of the present invention and is not intended to limit the scope of the present invention, and equivalent embodiments or modifications made without departing from the technical spirit of the present invention are included in the scope of the present invention.
Claims (10)
1. A liquid leakage type liquid level sensor is characterized by comprising an upper cover, an indicator light, a sealing screw, a sealing ring, a lower cover and a circuit unit; the upper cover and the lower cover are connected in an embedded mode through concave-convex grooves, the sealing ring is arranged between the upper cover and the lower cover, and the indicator light and the sealing screw are arranged on the upper portion of the upper cover; the bottom of the lower cover is provided with a supporting base; the circuit unit is arranged in a cavity formed by the upper cover and the lower cover;
the circuit unit comprises an induction capacitor, an oscillating circuit, an F/V conversion circuit, a signal processing unit, an output unit, a potentiometer, an indicating unit and a power circuit; the induction capacitor, the oscillating circuit, the F/V conversion circuit, the signal processing unit and the output unit are electrically connected in sequence; the output end of the potentiometer is electrically connected with the signal processing unit, and the input end of the indicating unit is electrically connected with the signal processing unit; the output end of the power supply circuit is electrically connected with the oscillating circuit, the F/V conversion circuit, the signal processing unit and the output unit respectively; the oscillation circuit adopts a crystal oscillator.
2. The leaky liquid level sensor as claimed in claim 1, wherein said sensing capacitor is a double-sided circular shielded circuit board.
3. The leaky level sensor as claimed in claim 1, wherein said potentiometer is a multi-turn potentiometer for adjusting sensitivity.
4. The leak level sensor as defined in claim 1, wherein the indicator light is an LED status indicator light.
5. The leaky liquid level sensor as claimed in claim 1, wherein said power circuit comprises a reverse connection preventing double diode, a regulated power supply, and a power chip; the voltage-stabilizing power supply comprises an 18V voltage-stabilizing tube and a triode which are electrically connected with each other; the stabilized voltage power supply is electrically connected with the power supply chip; the output pin of the power chip is connected with a high-capacity tantalum capacitor in parallel and used for voltage stabilization and filtering and providing stable +5V power supply.
6. The leak-type liquid level sensor as defined in claim 1, wherein the F/V conversion circuit employs a multi-channel gating chip using the crystal oscillator as a signal source.
7. The leaky level sensor as claimed in claim 1, wherein said signal processing unit includes a hysteretic comparator circuit employing a single power supply, high bandwidth, rail-to-rail operational amplifier; the in-phase end of the operational amplifier is electrically connected with the output end of the F/V conversion circuit, and the inverting end of the operational amplifier is electrically connected with a fixed reference voltage pin.
8. The leaky level sensor as claimed in claim 7, wherein said potentiometer includes an adjustment knob for adjusting a magnitude of a voltage signal at a non-inverting terminal of said operational amplifier.
9. The leaky level sensor as claimed in claim 1 or 8, wherein said output unit includes an output control element, a self-restoring fuse; the output control element adopts a triode; the self-recovery fuse is arranged at the output end of the output unit.
10. The leaky level sensor as defined in claim 1, further comprising a resistive guide rod; the lower end of the resistance guide rod is connected with the potentiometer, and the upper end of the resistance guide rod is connected with the sealing screw; the support base comprises 3 annular face domain structures; and a pattern drawing angle structure is arranged on the upper cover and/or the lower cover.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123011832.8U CN216524236U (en) | 2021-12-02 | 2021-12-02 | Liquid leakage type liquid level sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123011832.8U CN216524236U (en) | 2021-12-02 | 2021-12-02 | Liquid leakage type liquid level sensor |
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| Publication Number | Publication Date |
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| CN216524236U true CN216524236U (en) | 2022-05-13 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202123011832.8U Active CN216524236U (en) | 2021-12-02 | 2021-12-02 | Liquid leakage type liquid level sensor |
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| CN (1) | CN216524236U (en) |
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- 2021-12-02 CN CN202123011832.8U patent/CN216524236U/en active Active
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