CN210077387U

CN210077387U - Double-overheating protection circuit applied to water dispenser

Info

Publication number: CN210077387U
Application number: CN201920099399.1U
Authority: CN
Inventors: 唐林林; 刘小文
Original assignee: Dongguan Water Song Energy Saving Technology Co Ltd
Current assignee: Dongguan Water Song Energy Saving Technology Co Ltd
Priority date: 2019-01-21
Filing date: 2019-01-21
Publication date: 2020-02-18
Anticipated expiration: 2029-01-21

Abstract

The utility model discloses a be applied to two overheat protection circuit of water dispenser, two overheat protection circuit are including the MCU control circuit, drive control circuit and the relay that connect gradually, two overheat protection circuit is still including setting up thermistor and the mechanical over heater protection switch that resets on the heating tube of water dispenser, thermistor with MCU control circuit connects, the coil connection of drive control circuit and relay, the movable contact of relay is connected with an input of the power of heating tube, and the stationary contact of relay passes through the mechanical over heater protection switch that resets with another input of the power of heating tube is connected. The utility model discloses can prevent effectively that the phenomenon from appearing burning futilely in the heating tube of water dispenser, have advantages such as security height, good reliability, can effectively protect the water dispenser and stop the potential safety hazard.

Description

Double-overheating protection circuit applied to water dispenser

Technical Field

The utility model relates to a protection circuit, concretely relates to be applied to two overheat protection circuit of water dispenser.

Background

The traditional water dispenser adopts a hot water bag for heating, the heating speed is low, when the heated hot water is not taken in time, the water can be repeatedly heated again after the temperature of the hot water is reduced to form so-called 'thousand boiling water', the traditional water dispenser is not favorable for health, and the equipment is in a working state for a long time, has high power consumption and is not environment-friendly. In order to solve the defects of the traditional water dispenser, namely the hot water dispenser is produced at the right moment, the thick film heating technology is adopted, the heating is fast, the water stored in the inner container is not needed to be heated, and the water flow flows through the thick film pipe to heat the normal temperature water to the required temperature. In the water dispenser, if the heating tube in the water dispenser is lack of water or is dry-boiled, the heating tube of the water dispenser and even the circuit of the water dispenser are easily burnt out, which not only affects the service life of the water dispenser, but also has potential safety hazard. Therefore, it is necessary to provide a technical solution to prevent the heating tube of the water dispenser from being dry-burned.

SUMMERY OF THE UTILITY MODEL

In order to overcome the defects of the prior art and the existing problems, the utility model provides a double overheating protection circuit applied to a water dispenser, which can effectively prevent the heating tube of the water dispenser from being burnt dry by utilizing the protection circuit.

The utility model discloses a realize through following technical scheme: the double overheating protection circuit comprises an MCU control circuit, a drive control circuit and a relay which are sequentially connected, and further comprises a thermistor and a mechanical reset superheater protection switch which are arranged on a heating tube of the water dispenser, wherein the thermistor is connected with the MCU control circuit, the drive control circuit is connected with a coil of the relay, a movable contact of the relay is connected with one input end of a power supply of the heating tube, and a static contact of the relay is connected with the other input end of the power supply of the heating tube through the mechanical reset superheater protection switch.

Preferably, the MCU control circuit comprises an MCU, a resistor R1, a resistor R2 and a capacitor C1 connected in sequence, wherein one end of the resistor R1 is connected to a voltage source VDD, and one end of the capacitor C1 is grounded; one end of the thermistor is connected with the MCU through the resistor R2, and the other end of the thermistor is grounded.

Preferably, the thermistor is an NTC thermistor; the model of the MCU is 12C5A60S 2; the heating tube is a rare earth heating tube.

Preferably, the thermistor is welded at the high-level end of the heating tube; the mechanical reset overheat protection switch is attached to the low-level end of the heating tube.

The utility model discloses a set up thermistor and mechanical reset overheat protection switch on the heating tube of water dispenser to set up two overheat protection circuit of corresponding circuit component, can prevent effectively that the heating tube of water dispenser from appearing the phenomenon of burning futilely, have advantages such as security height, good reliability, can effectively protect the water dispenser and stop the potential safety hazard.

Drawings

Fig. 1 is a schematic diagram of a circuit structure of the dual overheat protection circuit of the present invention.

Detailed Description

To facilitate understanding of those skilled in the art, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

As shown in the attached figure 1, the double overheating protection circuit applied to the water dispenser comprises an MCU control circuit, a drive control circuit and a relay which are sequentially connected, and further comprises a thermistor and a mechanical reset superheater protection switch which are arranged on a heating tube of the water dispenser, wherein the thermistor is connected with the MCU control circuit, the drive control circuit is connected with a coil of the relay, a movable contact of the relay is connected with one input end of a power supply of the heating tube, and a static contact of the relay is connected with the other input end of the power supply of the heating tube through the mechanical reset superheater protection switch. In this embodiment, the thermistor is an NTC thermistor, and the heating tube is a rare earth heating tube. The driving control circuit is used for driving and controlling the relay so that the relay can normally work, therefore, the driving control circuit is a functional circuit which can be realized by the prior art, only a circuit which can drive and control the relay to work is needed, and the details are not described herein. In addition, the mechanical reset overheating protection switch only needs to adopt the components existing in the prior art, and the structure and the working principle of the mechanical reset overheating protection switch are not described in detail.

In a specific embodiment, the MCU control circuit includes an MCU, a resistor R1, a resistor R2, and a capacitor C1 connected in sequence, wherein one end of the resistor R1 is connected to a voltage source VDD, and one end of the capacitor C1 is grounded; one end of the thermistor is connected with the MCU through the resistor R2, and the other end of the thermistor is grounded. In this embodiment, the model of the MCU is preferably 12C5a60S 2.

In a preferred embodiment, the thermistor is welded at the high-end of the heat-generating tube; the mechanical reset overheat protection switch is attached to the low-level end of the heating tube. In this embodiment, the upstream end of the heating tube in the water flow direction is taken as the low end, and the downstream end of the heating tube in the water flow direction is taken as the high end, as shown in fig. 1.

The working process or working principle of the dual overheat protection circuit provided in the present embodiment is briefly described as follows: setting the temperature range of the NTC thermistor during normal operation, wherein the MCU control circuit can detect and calculate the resistance value of the NTC thermistor, and when the MCU control circuit detects and calculates the resistance value of the NTC thermistor during normal operation, the MCU control circuit outputs a corresponding control signal to drive the drive control circuit to output a corresponding drive signal, so that the relay is electrified and attracted, and a movable contact and a fixed contact of the relay are communicated, so that the heating tube works normally; when the heating tube is lack of water or is burnt, the NTC thermistor is heated, the temperature of the NTC thermistor exceeds the set temperature range in normal working, when the MCU control circuit detects and calculates that the resistance value of the NTC thermistor is abnormal, the MCU control circuit outputs a corresponding control signal to enable the drive control circuit to break off the drive signal, the relay is de-energized, and the movable contact and the fixed contact of the relay are in short circuit, so that the heating tube is de-energized, and the purpose of protecting the heating tube is achieved. In order to enhance the reliability of overheating protection, the mechanical reset overheating protection switch is further arranged, when the NTC thermistor protection is out of control and the heating tube is in an anhydrous dry-heating state, the temperature of the heating tube is continuously increased, and when the temperature is increased to the thermal warping temperature of a bimetal thermal deformation sheet of the mechanical reset overheating protection switch, the bimetal thermal deformation sheet deforms, so that the ceramic ejector rod is pushed to open the electric connection piece or the contact piece, the electric connection piece is separated from the contact piece, a power supply circuit of the heating tube is cut off, the heating tube stops heating, and dry-heating is stopped.

The above embodiments are preferred implementations of the present invention, and are not intended to be limiting, and any obvious replacement is within the scope of the present invention without departing from the inventive concept of the present invention.

Claims

1. The utility model provides a be applied to two overheat protection circuit of water dispenser which characterized in that: the double overheating protection circuit comprises an MCU control circuit, a drive control circuit and a relay which are sequentially connected, the double overheating protection circuit further comprises a thermistor and a mechanical reset superheater protection switch which are arranged on a heating tube of the water dispenser, the thermistor is connected with the MCU control circuit, the drive control circuit is connected with a coil of the relay, a movable contact of the relay is connected with one input end of a power supply of the heating tube, and a stationary contact of the relay is connected with the other input end of the power supply of the heating tube through the mechanical reset superheater protection switch.

2. The dual overheat protection circuit of claim 1, wherein: the MCU control circuit comprises an MCU, a resistor R1, a resistor R2 and a capacitor C1 which are sequentially connected, wherein one end of the resistor R1 is connected with a voltage source VDD, and one end of the capacitor C1 is grounded; one end of the thermistor is connected with the MCU through the resistor R2, and the other end of the thermistor is grounded.

3. The dual overheat protection circuit of claim 2, wherein: the thermistor is an NTC thermistor.

4. The dual overheat protection circuit of claim 2, wherein: the model of the MCU is 12C5A60S 2.

5. The dual overheat protection circuit of claim 1, wherein: the heating tube is a rare earth heating tube.

6. The dual overheat protection circuit according to any one of claims 1 to 5, wherein: the thermistor is welded at the high-level end of the heating tube.

7. The dual overheat protection circuit of claim 6, wherein: the mechanical reset overheat protection switch is attached to the low-level end of the heating tube.