Liquid level height alarm circuit

Abstract

The utility model provides a liquid level height alarm circuit. The liquid level height alarm circuit comprises a first metal detection head, a second metal detection head, a buzzer, a light-emitting LED, a capacitor and a triode, wherein the first metal detection head is connected with power supply voltage, the second metal detection head is connected with one end of the buzzer, the other end of the buzzer is connected with a collector electrode of the triode, an emitter electrode of the triode is grounded, and a base electrode of the triode is connected with the second metal detection head; the anode of the capacitor is connected with the second metal probe, and the cathode is connected with the emitter of the triode; the anode of the light-emitting LED is connected with the second metal detection head, and the cathode of the light-emitting LED is grounded. The utility model has the advantages that: on one hand, the circuit design is relatively simple and the cost is low; on the other hand, when the liquid level is lower than the early warning position, the LED lamp is turned off, and the buzzer gives out an alarm.

Description

Technical Field

[0001] The utility model relates to the technical field of liquid level measurement, and particularly relates to a liquid surface height alarm circuit. Background Art

[0002] The current liquid level alarm circuit is, on the one hand, relatively complex in design and high in cost; on the other hand, it often only has a buzzer alarm function. Content of the Utility Model

[0003] The purpose of the utility model is achieved through the following technical solutions.

[0004] The utility model realizes the purpose that when the liquid surface height is lower than the warning level, the LED lamp goes out and the buzzer emits an alarm sound at low cost.

[0005] Specifically, the utility model provides a liquid surface height alarm circuit, including:

[0006] A first metal detection head, a second metal detection head, a buzzer, a light-emitting LED, a capacitor, and a triode; wherein,

[0007] The first metal detection head is connected to the supply voltage, one end of the second metal detection head is connected to the buzzer, the other end of the buzzer is connected to the collector of the triode, the emitter of the triode is grounded, and the base is connected to the second metal detection head;

[0008] The anode of the capacitor is connected to the second metal detection head, and the cathode is connected to the emitter of the triode;

[0009] The anode of the light-emitting LED is connected to the second metal detection head, and the cathode is grounded.

[0010] Further, the first metal detection head is connected to the supply voltage through a third resistor.

[0011] Further, the emitter of the triode is grounded through a first diode, wherein the emitter of the triode is connected to the anode of the first diode, and the cathode of the first diode is grounded.

[0012] Further, the base of the triode is connected to the second metal detection head through a second resistor.

[0013] Further, the alarm circuit further includes a second diode, and the base of the triode is also connected to the anode of the second diode, and the cathode of the second diode is grounded.

[0014] Further, the alarm circuit further includes a first resistor, and the anode of the light-emitting LED is connected to the second metal detection head through the first resistor.

[0015] Further, the first metal detection head and the second metal detection head are separately placed at the position of the warning liquid level height.

[0016] Further, when the liquid level is higher than the first metal detector head and the second metal detector head, the first metal detector head and the second metal detector head are turned on. After the supply voltage is powered on, the light-emitting LED is lit and the capacitor is charged.

[0017] Further, when the liquid level is lower than the first metal detector head and the second metal detector head, the capacitor discharges, the triode is turned on, and the buzzer works.

[0018] Further, the liquid in which the first metal detector head and the second metal detector head are immersed is a conductive liquid.

[0019] The advantages of the present utility model are as follows: on the one hand, the circuit design is relatively simple and the cost is low; on the other hand, it realizes the purpose that when the liquid level is lower than the warning level, the LED light is turned off and the buzzer emits an alarm sound. Description of the Drawings

[0020] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present utility model. Moreover, throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0021] Attached Figure 1 shows a liquid level height alarm circuit diagram according to an embodiment of the present utility model. Detailed Embodiments

[0022] Hereinafter, exemplary embodiments of the present disclosure will be described in more detail with reference to the drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be completely conveyed to those skilled in the art.

[0023] As Figure 1 shown, according to an embodiment of the present utility model, a liquid level height alarm circuit is proposed, including: metal detector heads A and B, resistors R1, R2, R3, capacitor C1, triode Q1, light-emitting LED, diodes D1 and D2. It should be noted that in the circuit diagram of this embodiment, the first metal detector head A, the second metal detector head B, the buzzer, the light-emitting LED, the capacitor C1, and the triode Q1 are essential components, while other components, the resistors R1, R2, R3, and the diodes D1 and D2, are not essential components and can be appropriately omitted.

[0024] In the basic embodiment, the first metal detector head is connected to the supply voltage, the second metal detector head is connected to one end of the buzzer, the other end of the buzzer is connected to the collector of the triode, the emitter of the triode is grounded, and the base is connected to the second metal detector head;

[0025] The anode of the capacitor is connected to the second metal detector head, and the cathode is connected to the emitter of the triode;

[0026] The anode of the light-emitting LED is connected to the second metal detector head, and the cathode is grounded.

[0027] In another embodiment, as Figure 1 shown, A is connected to the supply voltage VCC through the resistor R3, and B is connected to one end of the buzzer. The other end of the buzzer is connected to the collector of the triode. The emitter of the triode is connected to the anode of the diode D1, the cathode of D1 is grounded, and the base of the triode is connected to B through the resistor R2. The base is also connected to the anode of the diode D2, and the cathode of D2 is grounded. The anode of the capacitor C1 is connected to B, and the cathode is connected to the emitter of the triode. One end of the resistor R1 is connected to B, and the other end is connected to the anode of the light-emitting LED. The cathode of the light-emitting LED is grounded.

[0028] In the present utility model, A and B are metal detector heads, which are separately placed at the position of the warning liquid level height. Under normal circumstances, when the liquid level is higher than the A and B measuring points, A and B are conducting. After VCC is powered on, VCC1 is connected to VCC through the conducting detector heads A, B, and R3, the LED lamp is lit, and the electrolytic capacitor C1 is charged.

[0029] In the present utility model, when the liquid level height is lower than the positions of A and B, VCC1 is disconnected from R3 and VCC, the electrolytic capacitor C1 discharges, the NPN-type triode Q1 conducts, and the active buzzer Bell works.

[0030] In the present utility model, the capacitance of C1 is the main factor determining the working duration of the buzzer.

[0031] In the present utility model, the liquid in which A and B are immersed needs to be a conductive liquid.

[0032] The above is only the preferred specific embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present utility model should be covered by the protection scope of the present utility model. Therefore, the protection scope of the present utility model should be subject to the protection scope of the claims.

Claims

1. A liquid level height alarm circuit, characterized in that, Including: A first metal detector head, a second metal detector head, a buzzer, a light-emitting LED, a capacitor, and a triode; wherein, The first metal detector head is connected to the supply voltage, one end of the second metal detector head is connected to the buzzer, the other end of the buzzer is connected to the collector of the triode, the emitter of the triode is grounded, and the base is connected to the second metal detector head; The anode of the capacitor is connected to the second metal detector head, and the cathode is connected to the emitter of the triode; The anode of the light-emitting LED is connected to the second metal detector head, and the cathode is grounded.

2. The liquid level height alarm circuit according to claim 1, wherein The first metal detector head is connected to the supply voltage through a third resistor.

3. The liquid level height alarm circuit according to claim 1, wherein The emitter of the triode is grounded through a first diode, wherein the emitter of the triode is connected to the anode of the first diode, and the cathode of the first diode is grounded.

4. The liquid level height alarm circuit according to claim 1, wherein The base of the triode is connected to the second metal detector head through a second resistor.

5. The liquid level height alarm circuit according to claim 1, wherein The alarm circuit further includes a second diode, and the base of the triode is also connected to the anode of the second diode, and the cathode of the second diode is grounded.

6. The liquid level height alarm circuit according to claim 1, wherein The alarm circuit further includes a first resistor, and the anode of the light-emitting LED is connected to the second metal detector head through the first resistor.

7. The liquid level height alarm circuit according to claim 1, wherein The first metal detector head and the second metal detector head are separately placed at the position of the warning liquid level height.

8. The liquid level height alarm circuit according to any one of claims 1-7, wherein When the liquid level is higher than the first metal detector head and the second metal detector head, the first metal detector head and the second metal detector head are turned on. After the supply voltage is energized, the light-emitting LED is lit and the capacitor is charged.

9. The liquid level height alarm circuit according to any one of claims 1-7, wherein When the liquid level height is lower than the first metal detector head and the second metal detector head, the capacitor discharges, the triode is turned on, and the buzzer works.

10. The liquid level height alarm circuit according to claim 1, wherein The liquid in which the first metal detector head and the second metal detector head are immersed is a conductive liquid.

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