Liquid heating control system

Abstract

The utility model provides a liquid heating control system which comprises a heating assembly, a main power supply loop, a double-single-chip microcomputer control circuit and an interface circuit. The heating assembly comprises a resistance wire and a temperature sensor, and the heating assembly and the double-single-chip microcomputer control circuit are both connected with the main power supply loop. The temperature sensor converts level through the interface circuit, isolates the level through the isolation chip, and transmits the level to the double-single-chip microcomputer control circuit. According to the utility model, the plurality of logic control chips are mutually backed up and supervised, so that the overheating risk caused by the dead halt of the single-chip microcomputer is avoided to the greatest extent. The device is simple in structure, convenient to use and high in safety.

Description

Technical Field

[0001] The utility model belongs to the technical field of control systems, and particularly relates to a liquid heating control system. Background Art

[0002] Currently, when a patient is receiving an infusion or a blood transfusion, or both an intravenous infusion and a blood transfusion simultaneously, it is mostly not heated. Especially when the blood needs to be refrigerated, it is necessary to heat the blood to the human body temperature during the blood transfusion process, which is more comfortable when it enters the human body. The traditional heating method is to use a resistance wire heating method. However, this method has a major risk. Due to various reasons, when the heating gets out of control, the liquid temperature will be too high or even boil, which is an unacceptable risk. To eliminate this high risk, the utility model has developed a safe liquid heating control system. Summary of the Invention

[0003] In view of this, the utility model aims to overcome the above deficiencies in the prior art and proposes a liquid heating control system.

[0004] To achieve the above object, the technical solution of the utility model is realized as follows:

[0005] A liquid heating control system includes a heating component, a main power supply circuit, a dual single-chip microcomputer control circuit, and an interface circuit;

[0006] The main power supply circuit includes a power input interface, which is respectively connected to the first end of resistor R2, the negative electrode of diode D3, the first end of the relay coil, and the normally closed contact of the relay. The positive electrode of diode D3 and the second end of the relay coil are connected to the collector of triode Q5. The emitter of triode Q5 is grounded. The base of triode Q5 is respectively connected to the first end of resistor R12 and the first end of resistor R17. The second end of resistor R12 is grounded. The second end of resistor R2 is connected to the first end of capacitor C26. The second end of capacitor C26 is respectively connected to the normally open contact of the relay, the first end of capacitor C29, the first end of capacitor C6, and the IP+ end of current sensor U6. The second end of capacitor C29 and the second end of capacitor C6 are grounded. The VCC end of current sensor U6 is respectively connected to the 5V power supply and the first end of capacitor C11. The second end of capacitor C11 is grounded. The VIOUT end of current sensor U6 is respectively connected to the first end of capacitor C34, the RA2 end of microcontroller U9, and the RA2 end of microcontroller U11. The second end of capacitor C34 is grounded. The BwSel end of current sensor U6 is connected to the 5V power supply. The IP- end of current sensor U6 is connected to the negative electrode of diode D1. The positive electrode of diode D1 is connected to the first end of the Schottky diode. The second end of the Schottky diode is respectively connected to the first end of inductor L1 and the D pole of VMOS transistor Q1. The S pole of VMOS transistor Q1 is grounded. The G pole of VMOS transistor Q1 is connected to the first end of resistor R19. The second end of inductor L1 is respectively connected to the first end of capacitor C30 and the first end of capacitor C7. The second end of capacitor C30 and the second end of capacitor C7 are grounded;

[0007] The heating component includes a heating wire and a temperature sensor. The heating component and the dual-microcontroller control circuit are both connected to the main power supply circuit;

[0008] The temperature sensor converts the level through the interface circuit, is isolated by the isolation chip, and is transmitted to the dual-microcontroller control circuit.

[0009] Further, the dual-microcontroller control circuit includes a first microcontroller control circuit and a second microcontroller control circuit. The first microcontroller control circuit includes a first control chip, and the second control circuit includes a second control chip.

[0010] Further, both the first control chip and the second control chip adopt chips with the model of PIC16F1823-I / SL.

[0011] Further, the isolation chip adopts a chip with the model of π120U31.

[0012] Compared with the prior art, the liquid heating control system of the present utility model has the following advantages:

[0013] 1. Multiple logic control chips are backed up and supervised by each other to minimize the overheating risk caused by the single-chip microcomputer crashing.

[0014] 2. The utility model has a simple structure, is convenient to use and has high safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The attached drawings forming a part of the present utility model are used to provide a further understanding of the present utility model. The schematic embodiments and descriptions thereof of the present utility model are used to explain the present utility model and do not constitute an improper limitation to the present utility model. In the drawings:

[0016] Figure 1 is a schematic diagram of the principle of a liquid heating control system of the present utility model;

[0017] Figure 2 is the circuit diagram of the main power supply circuit of the present utility model;

[0018] Figure 3 is a schematic diagram of the interface circuit and the dual single-chip microcomputer control circuit of the present utility model;

[0019] Figure 4 is a schematic diagram of the isolation chip circuit of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments can be combined with each other.

[0021] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. can explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0022] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0023] The present utility model will be described in detail below with reference to the drawings and in conjunction with embodiments.

[0024] As Figure 1 shown, the present utility model provides a liquid heating control system, including a heating component, a main power supply circuit, a dual single-chip microcomputer control circuit, and an interface circuit; wherein, the electric heating component and the dual single-chip microcomputer control circuit are both connected to the main power supply circuit through the interface circuit;

[0025] Specifically, as Figure 2 shown, the main power supply circuit includes a power input interface, and the power input interface is respectively connected to the first end of a resistor R2, the negative electrode of a diode D3, the first end of a relay coil, and a relay normally closed contact. The positive electrode of the diode D3 and the second end of the relay coil are connected to the collector of a triode Q5. The emitter of the triode Q5 is grounded. The base of the triode Q5 is respectively connected to the first end of a resistor R12 and the first end of a resistor R17. The second end of the resistor R12 is grounded. The second end of the resistor R2 is connected to the first end of a capacitor C26. The second end of the capacitor C26 is respectively connected to a relay normally open contact, the first end of a capacitor C29, the first end of a capacitor C6, and the IP+ end of a current sensor U6. The second ends of the capacitor C29 and the capacitor C6 are grounded. The VCC end of the current sensor U6 is respectively connected to a 5V power supply and the first end of a capacitor C11. The second end of the capacitor C11 is grounded. The VIOUT end of the current sensor U6 is respectively connected to the first end of a capacitor C34, the RA2 end of a single-chip microcomputer U9, and the RA2 end of a single-chip microcomputer U11. The second end of the capacitor C34 is grounded. The BwSel end of the current sensor U6 is connected to the 5V power supply. The IP- end of the current sensor U6 is connected to the negative electrode of a diode D1. The positive electrode of the diode D1 is connected to the first end of a Schottky diode. The second end of the Schottky diode is respectively connected to the first end of an inductor L1 and the D pole of a VMOS transistor Q1. The S pole of the VMOS transistor Q1 is grounded. The G pole of the VMOS transistor Q1 is connected to the first end of a resistor R19. The second end of the inductor L1 is respectively connected to the first end of a capacitor C30 and the first end of a capacitor C7. The second ends of the capacitor C30 and the capacitor C7 are grounded;

[0026] In the present utility model, the heating component is connected to the socket J1, and the positive electrode is connected to the positive electrode of the main power supply after passing through an electronic switch, a relay mechanical switch, and a current detection unit. The heating component includes a resistance wire and a temperature sensor. The resistance wire is connected between PL and HOTL, and the temperature sensor is connected between L-TEMP and TGND. The 24V working power supply passes through the contacts 1 and 3 of the relay RY1, passes through the current sensor U6 to the PL terminal, and after passing through the resistance wire, the temperature of the resistance wire is controlled to a predetermined constant value by the on-off mode of the VMOS transistor Q1.

[0027] Specifically, as Figure 3 , 4 shown, the dual single-chip microcomputer control circuit includes a first single-chip microcomputer control circuit and a second single-chip microcomputer control circuit. The first single-chip microcomputer control circuit includes a first control chip, and the second control circuit includes a second control chip. Both the first control chip and the second control chip use chips with the model PIC16F1823-I / SL, and the two chips are connected to each other. The temperature sensor data L-TEMP is converted to L-TX through an interface circuit, isolated by the isolation chip U3, and converted to the label RX-L to the single-chip microcomputer U9 as the basis for temperature regulation.

[0028] When the present utility model is working, the real-time current IL signal of the main power supply circuit is simultaneously transmitted to the single-chip microcomputers U9 and U11, and the state of the device is monitored by two identical single-chip microcomputers. Heartbeat packet data is sent and received between the two single-chip microcomputers to verify that each other is alive and normal. If the temperature control transistor Q1 is short-circuited and damaged, a dangerous fault of continuous heating will occur. At this time, the single-chip microcomputer U9 detects that Q1 has been turned off but the IL signal shows abnormal current. The single-chip microcomputer U9 turns off the relay RY1, thus avoiding the disaster of overheating. At the same time, if the single-chip microcomputer sends a conduction signal to Q1 but no normal current is detected on IL, it means that the heating resistance wire is not heating normally, and an alarm can be given in time to prevent long-term ineffective operation.

[0029] When U9 or U11 cannot receive the heartbeat packet data of the other party, it is considered that the other party has crashed and lost control. Either U9 or U11 can actively turn off the relay RY1, thereby minimizing the damage.

[0030] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. A liquid heating control system, characterized in that: It includes a heating component, a main power supply circuit, a dual single-chip control circuit and an interface circuit; The main power supply circuit includes a power input interface, which is respectively connected to the first end of the resistor R2, the cathode of the diode D3, the first end of the relay coil and the normally closed contact of the relay, the anode of the diode D3 and the second end of the relay coil are connected to the collector of the transistor Q5, the emitter of the transistor Q5 is grounded, the base of the transistor Q5 is respectively connected to the first end of the resistor R12 and the first end of the resistor R17, the second end of the resistor R12 is grounded, the second end of the resistor R2 is connected to the first end of the capacitor C26, the second end of the capacitor C26 is respectively connected to the normally open contact of the relay, the first end of the capacitor C29, the first end of the capacitor C6, and the IP+ end of the current sensor U6, the second end of the capacitor C29 and the second end of the capacitor C6 are grounded, and the VCC end of the current sensor U6 is respectively connected to the 5V power supply and the capacitor The first end of C11 and the second end of capacitor C11 are grounded, the VIOUT end of current sensor U6 is respectively connected to the first end of capacitor C34, the RA2 end of single-chip microcomputer U9, and the RA2 end of single-chip microcomputer U11, the second end of capacitor C34 is grounded, the BwSel end of current sensor U6 is connected to a 5V power supply, the IP- end of current sensor U6 is connected to the cathode of diode D1, the anode of diode D1 is connected to the first end of Schottky diode, the second end of Schottky diode is respectively connected to the first end of inductor L1 and the D pole of VMOS tube Q1, the S pole of VMOS tube Q1 is grounded, the G pole of VMOS tube Q1 is connected to the first end of resistor R19, the second end of inductor L1 is respectively connected to the first end of capacitor C30 and the first end of capacitor C7, the second end of capacitor C30 and the second end of capacitor C7 are grounded; The heating component includes a resistance wire and a temperature sensor, and the heating component and the dual single-chip control circuit are both connected to the main power supply circuit; The temperature sensor is isolated through an isolation chip by converting the level of the interface circuit and then transmitted to the dual single-chip control circuit.

2. A liquid heating control system according to claim 1, characterized in that: The dual single-chip control circuit includes a first single-chip control circuit and a second single-chip control circuit. The first single-chip control circuit includes a first control chip, and the second single-chip control circuit includes a second control chip.

3. A liquid heating control system according to claim 2, characterized in that: The first control chip and the second control chip are both PIC16F1823-I / SL chips.

4. A liquid heating control system according to claim 1, characterized in that: The isolation chip adopts a chip model of π120U31.

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