Timing adjustable and protection circuit for electric heating mosquito-repellent incense

Abstract

The utility model belongs to the technical field of automatic temperature control devices, and particularly relates to a timing adjustable and protection circuit for electric mosquito-repellent incense, which comprises a counting circuit, and the input end of the counting circuit is connected with a timing duration setting circuit and a timing increasing and decreasing direction control circuit. The output end of the counting circuit is connected with the minute timing circuit and the AND gate circuit, the output end of the minute timing circuit is connected with the frequency dividing circuit, and the output end of the frequency dividing circuit is connected with the trigger holding circuit. The hot rod is prevented from being in a dry burning state after the mosquito-repellent incense liquid is used up; the state of the equipment is detected through a ball switch sensor, and if the equipment is in an inclined state, heating is stopped; and a timing power-off function is realized by using a counter and a timer.

Description

Technical Field

[0001] The utility model relates to the technical field of temperature automatic control devices, in particular to an electric heating mosquito-repellent incense timing adjustable and protection circuit. Background Technique

[0002] The electric heating mosquito-repellent incense device uses the constant temperature effect of a heating element to slowly release a drug, and volatilizes a gas to kill and repel mosquitoes.

[0003] However, the following technical problems still exist when the existing electric heating mosquito-repellent incense is in use:

[0004] The existing electric heating mosquito-repellent incense device uses the mains power as the power source for the heating element. The device can work as long as it is connected to the mains power, without a timing power-off function, and requires manual power-off. If the power-off is forgotten, the device will continue to work. When the mosquito-repellent liquid has evaporated, the heating rod in the mosquito-repellent incense device will be in a dry-burning state, posing a fire hazard. There is no tilting detection function, and the device will continue to work even if it is tilted. There is a fire hazard caused by the leakage of the mosquito-repellent liquid. There is no mosquito-repellent liquid level detection function, and the heating rod cannot stop heating in time after the mosquito-repellent liquid has evaporated.

[0005] Therefore, an electric heating mosquito-repellent incense timing adjustable and protection circuit is proposed to solve the above-mentioned problems. Content of the Utility Model

[0006] The purpose of the utility model is to provide an electric heating mosquito-repellent incense timing adjustable and protection circuit to solve the problems raised in the above background technique.

[0007] To achieve the above purpose, the utility model provides the following technical solution: An electric heating mosquito-repellent incense timing adjustable and protection circuit includes a counting circuit. The input end of the counting circuit is connected with a timing duration setting circuit and a timing increase / decrease direction control circuit. The output end of the counting circuit is connected with a minute timing circuit and an AND gate circuit. The output end of the minute timing circuit is connected with a frequency division circuit. The output end of the frequency division circuit is connected with a trigger holding circuit. The output end of the trigger holding circuit is connected with a timer reset control circuit and a relay drive circuit. The output end of the timer reset control circuit is connected with the input end of the minute timing circuit. The output end of the relay drive circuit is connected with a heating element. The output end of the AND gate circuit is connected with the input end of the relay drive circuit. The input end of the AND gate circuit is connected with a liquid level detection circuit and an inclination detection circuit.

[0008] Preferably, the timing increase / decrease direction control circuit includes a touch button S1, a pull-up resistor R9, a capacitor C4, a flip-flop U11A, an indicator LED1, an indicator LED3, a resistor R4, a resistor R18, a normally-closed analog switch S2A, and a pull-down resistor R2. The touch button S1 is connected to the pull-up resistor R9 and the capacitor C4. The capacitor C4 is connected to the flip-flop U11A. The flip-flop U11A is connected to the indicator LED1 and the indicator LED3. The indicator LED1 is connected to the resistor R18. The indicator LED3 is connected to the resistor R4. The right ends of the indicator LED1 and the indicator LED3 are connected to the normally-closed analog switch S2A. The right end of the normally-closed analog switch S2A is connected to the pull-down resistor R2.

[0009] Preferably, the timing duration setting circuit includes a touch button S9, a pull-down resistor R15, and a capacitor C5. The touch button S9 is connected to the pull-down resistor R15 and the capacitor C5. The other ends of the pull-down resistor R15 and the capacitor C5 are grounded.

[0010] Preferably, the counting circuit includes a counter U1 and an OR gate device U6A. The 3, 2, 6, and 7 pins of the counter U1 are connected to the OR gate device U6A.

[0011] Preferably, the minute timing circuit includes a 555 timer A1, analog switches S5, S4, resistors R1, R6, R7, R10, R11, R12, R13, R14, R5, capacitors C2 and C3.

[0012] Preferably, the frequency division circuit includes U3, U4, U5A, U5C, U5B. The 14th pin of U3 is connected to the OUT output of A1. The 11th pin of U3 is connected to U5C. The input ends of U5C and U5B are connected to the 6th and 7th pins of U3. The output end of U5B is connected to the 14th pin of U4. The 3rd and 6th pins of U4 are connected to U5A. The trigger and hold circuit includes Q1, R3, R16, U11B. The 11th pin of U11B is connected to Q1 and R16.

[0013] Preferably, the liquid level detection circuit includes Q4 and R28. The tilt detection circuit includes R21, R22, C1, R24, U7A, R25, and S10.

[0014] Preferably, the AND gate circuit includes D2, D3, D4, which are connected in parallel. The relay drive circuit includes LED4, resistors R19, R20, transistor Q2, resistor R17, resistor R23, transistor Q3, diode D1, and relay K1.

[0015] Preferably, the timer reset control circuit includes a resistor R27, a resistor R26, and a triode Q5. The input end of the triode Q5 is connected to the resistor R27, and the output end of the resistor R27 is connected to the resistor R26.

[0016] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0017] The present invention detects the stock of the mosquito-repellent liquid in real time through a liquid level detection sensor, avoiding the dry burning state of the heating rod due to the exhaustion of the mosquito-repellent liquid; detects the state of the device through a ball switch sensor, and stops heating if it is in an inclined state; uses a counter and a 555 timer to achieve the function of timed power-off. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic block diagram of the present utility model;

[0019] Figure 2 is a circuit diagram for controlling the direction of timed increase and decrease;

[0020] Figure 3 is a circuit diagram for setting the timed duration;

[0021] Figure 4 is a counting circuit diagram;

[0022] Figure 5 is a minute timing circuit diagram;

[0023] Figure 6 is a frequency division circuit diagram;

[0024] Figure 7 is a trigger holding circuit diagram;

[0025] Figure 8 is a liquid level detection circuit diagram;

[0026] Figure 9 is an inclination detection circuit diagram;

[0027] Figure 10 is an AND gate circuit and a relay drive circuit diagram;

[0028] Figure 11 is a timer reset control circuit diagram.

[0029] In the figure: 1 is a circuit for controlling the direction of timed increase and decrease, 2 is a circuit for setting the timed duration, 3 is a counting circuit, 4 is a minute timing circuit, 5 is a frequency division circuit, 6 is a trigger holding circuit, 7 is a liquid level detection circuit, 8 is an inclination detection circuit, 9 is an AND gate circuit, 10 is a relay drive circuit, and 11 is a timer reset control circuit. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention 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 should not be construed as a limitation to the present invention.

[0032] Embodiment:

[0033] Please refer to Figures 1-11 , the present invention provides a technical solution:

[0034] An electric heating mosquito repellent timer adjustable and protection circuit, including a counting circuit 3, the input end of the counting circuit 3 is connected with a timing duration setting circuit 2 and a timing increase / decrease direction control circuit 1, the output end of the counting circuit 3 is connected with a minute timing circuit 4 and an AND gate circuit 9, the output end of the minute timing circuit 4 is connected with a frequency division circuit 5, the output end of the frequency division circuit 5 is connected with a trigger holding circuit 6, the output end of the trigger holding circuit 6 is connected with a timer reset control circuit 11 and a relay drive circuit 10, the output end of the timer reset control circuit 11 is connected with the input end of the minute timing circuit 4, the output end of the relay drive circuit 10 is connected with a heating element 12, the output end of the AND gate circuit 9 is connected with the input end of the relay drive circuit 10, and the input end of the AND gate circuit 9 is connected with a liquid level detection circuit 7 and an inclination detection circuit 8.

[0035] The timing increase / decrease direction control circuit 1 includes a touch button S1, a pull-up resistor R9, a capacitor C4, a flip-flop U11A, an indicator LED1, an indicator LED3, a resistor R4, a resistor R18, a normally-closed analog switch S2A, and a pull-down resistor R2. The touch button S1 is connected to the pull-up resistor R9 and the capacitor C4. The capacitor C4 is connected to the flip-flop U11A. The flip-flop U11A is connected to the indicator LED1 and the indicator LED3. The indicator LED1 is connected to the resistor R18. The indicator LED3 is connected to the resistor R4. The right ends of the indicator LED1 and the indicator LED3 are connected to the normally-closed analog switch S2A. The right end of the normally-closed analog switch S2A is connected to the pull-down resistor R2. After the device is powered on and S1 is not pressed, the pin1 of U11A outputs a high level, LED1 lights up, and LED3 is off; when the S2A switch is opened, pin1 and pin2 are disconnected, and pin2 outputs a low level; the U_D network is at a low level, and the counter U1 counts up, so that the device is default set to increase the timing when powered on. By generating a trigger pulse through the touch button S1, when the pin3 of U11A recognizes the rising edge, the output state of the pin1 of U11A flips between high and low levels and maintains the current level state; that is, the pin1 of U11A changes from a high level to a low level, LED3 lights up, and LED1 is off. At this time, the S2A switch is closed, pin1 and pin2 of S2A are conducted, the U_D network is at a high level, and the counter U1 counts down. The device can identify whether it is set to increase or decrease by whether LED1 and LED3 are lit.

[0036] The timing duration setting circuit 2 includes a touch button S9, a pull-down resistor R15, and a capacitor C5. The touch button S9 is connected to the pull-down resistor R15 and the capacitor C5. The other ends of the pull-down resistor R15 and the capacitor C5 are grounded. A trigger pulse is provided to U1 through the touch button S9 for setting the timing duration of the device.

[0037] The counting circuit 3 includes a counter U1 and an OR gate device U6A. The 3.2.6.7 pins of the counter U1 are connected to the OR gate device U6A. It is connected to the trigger hold circuit 2 through the pin5 of U1. When the pin5 is at a low level, it counts up, otherwise it counts down; through the pin14 of U1 to the timing duration setting circuit 2, each time a rising edge is obtained, the output changes by 1; the output changes in hexadecimal between 0 and 15; the input of the OR gate U6A is connected to the output of U1, and the output 555_RST of the OR gate U6A is connected to D2 of the AND gate circuit and the RST pin of the timer A1, and is also connected to the collector of Q5 at the same time; when the device is powered on and the duration is not set, the output of U1A is 0000, and the output 555_RST of U6A is 0, so that the heating rod is default not powered on after the device is powered on.

[0038] The minute timing circuit 4 includes a 555 timer A1, analog switches S5, S4, resistors R1, R6, R7, R10, R11, R12, R13, R14, R5, capacitors C2 and C3. Pin 3 and pin 2 of U1 are respectively connected to pin 1 and pin 14 of S5, and pin 6 and pin 7 of U1 are respectively connected to pin 1 and pin 14 of S4. The closing and opening of the internal analog switches of S4 and S5 are controlled by the output of U1. When the output DCBA of U1 is 0001, pin 6 and pin 5 of S5 are conducted, and pin 6 and pin 4 of S4 are conducted, and the output of U6A is 1, and the timer A1 starts to work. At this time, R5 is connected to R6, R11, and C2, and the power supply charges C2 through R5, R6, and R11. The charging time t_charge ≈ 0.7 * (R5 + R6 + R11) * C2. When it is charged to 2 / 3VCC, 555 resets, and the output OUT of A1 is at a low level. At this time, C2 discharges through R6 and R11, and the discharge time t_discharge ≈ 0.7 * (R6 + R11) * C2. Therefore, the frequency of the PWM output by 555 is f ≈ 1 / T = 1 / (t_charge + t_discharge) = 1.43 / [(R5 + 2R6 + 2R11) * C2]. By analogy, when the output DCBA of U1 is 0010, the frequency of the PWM output by 555 is 1.43 / [(R5 + 2R7 + 2R11) * C2]. By selecting appropriate resistor and capacitor values, A1 can output 15 different square waves with different periods in minutes.

[0039] The frequency division circuit 5 includes U3, U4, U5A, U5C, U5B. The 14th pin of U3 is connected to the OUT output of A1, the 11th pin of U3 is connected to U5C, the input terminals of U5C and U5B are connected to the 6th and 7th pins of U3, the output terminal of U5B is connected to the 14th pin of U4, and the 3rd and 6th pins of U4 are connected to U5A; the trigger hold circuit 6 includes Q1, R3, R16, U11B, and the 11th pin of U11B is connected to Q1 and R16; thus realizing timing in hours. When the preset time is reached, the inputs of U5A are all 1, and at this time the output changes from high level to low level; when the preset time is reached, the output of U5A changes from high level to low level, CTR_OUT is at a low level, Q1 is not conducted, and the pin 11 of U11B changes from low level to high level. At this time, the output of U11B changes from low level to high level and maintains at a high level state.

[0040] The liquid level detection circuit 7 includes Q4 and R28. When the sensor recognizes that the mosquito repellent liquid is at a low level, W_SEN changes from high level to low level, and vice versa, it is always at high level. The tilt detection circuit 8 includes R21, R22, C1, R24, U7A, R25, and S10. When the device is tilted, S10 closes, and through the comparator U7A, G_SEN outputs a low level, and vice versa, G_SEN is at high level.

[0041] The AND gate circuit 9 includes D2, D3, and D4. D2, D3, and D4 are in parallel. When any one of G_SEN, W_SEN, and 555_RST is at low level, S_IN is at low level. The relay drive circuit 10 includes LED4, resistor R19, resistor R20, transistor Q2, resistor R17, resistor R23, transistor Q3, diode D1, and relay K1. The output of the trigger and hold circuit 6 is used as the input of the relay drive circuit 10. When the preset time is reached, U11B outputs a high level; transistor Q2 conducts, and the collector is at low level; at this time, Q3 does not conduct, the relay does not work, and the power supply of the heating rod U2 is disconnected and does not work. Conversely, the heating rod is in a normal power supply state.

[0042] The timer reset control circuit 11 includes resistor R27, resistor R26, and transistor Q5. The input end of transistor Q5 is connected to resistor R27, the output end of resistor R27 is connected to resistor R26, the output of the trigger and hold circuit 6 is used as the input of the relay reset control circuit 11, and the output of the relay reset control circuit 11 is used as the input of the RST pin of the 555 timer A1; when the preset time is reached, K_CTR is at high level, 555_RST is at low level, and A1 stops working.

[0043] Working principle:

[0044] 1. After the device is powered on and before the timing time is set, U1 outputs 0000. At this time, 555_RST outputs 0; the 555 timer does not work, and Q3 does not conduct, so the relay does not work; finally, the heating rod is not powered. Therefore, the device defaults to not being turned on after being powered on;

[0045] 2. After the device is powered on, U_D defaults to low level. The timing duration can be directly increased by pressing the touch button S9; if the duration needs to be shortened, the level of U_D needs to be changed to high by pressing the touch button S1 first, and then the timing duration can be decreased by pressing the touch button S9;

[0046] 3. Fifteen kinds of timing time settings are realized by switching through the analog switches D5 and D4; when the time setting is completed, 555_RST is at high level, and the 555 timer A1 starts to work, outputting a periodic square wave with the preset unit of minutes; then it is divided by the counters U3 and U4 to finally realize the timing in units of hours;

[0047] 4. When the time setting is completed and the preset time has not been reached, and the device is not tilted and the mosquito-repellent liquid is sufficient; U5A outputs a high level for CTR_OUT, U11B outputs a low level for K_CTR, and Q2 is not turned on; also, since G_SEN, W_SEN, and 555_RST are all high levels, S_IN is a high level, Q3 is turned on, the relay works, the heating rod U2 is normally powered, and the device is in normal operation.

[0048] 5. When the device is tilted, G_SEN is at a low level, Q3 is not turned on, the relay stops working, the power supply of the heating rod U2 is disconnected, and the device stops working;

[0049] 6. When the liquid level of the mosquito-repellent liquid in the device is low, W_SEN is at a low level, Q3 is not turned on, the relay stops working, the power supply of the heating rod U2 is disconnected, and the device stops working;

[0050] 7. When the device reaches the preset time, U5A outputs a low level for CTR_OUT, Q1 is not turned on, the input level of U11B flips from low to high, so the output K_CTR changes to a high level and remains in the high-level state; at this time, Q5 is turned on, 555_RST is at a low level, and A1 stops working; Q2 is turned on, Q3 is not turned on, the relay stops working, the power supply of the heating rod U2 is disconnected, and the device stops working.

[0051] The above shows and describes the basic principles, main features and advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic features of the present invention; therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention, and any reference signs in the claims should not be regarded as limiting the claims involved.

[0052] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An electric mosquito coil timing adjustable and protective circuit, comprising a counting circuit (3), characterized in that: The input end of the counting circuit (3) is connected to a timing duration setting circuit (2) and a timing increase / decrease direction control circuit (1); the output end of the counting circuit (3) is connected to a minute timing circuit (4) and an AND gate circuit (9); the output end of the minute timing circuit (4) is connected to a frequency dividing circuit (5); the output end of the frequency dividing circuit (5) is connected to a trigger holding circuit (6); the output end of the trigger holding circuit (6) is connected to a timer reset control circuit (11) and a relay drive circuit (10); the output end of the timer reset control circuit (11) is connected to the input end of the minute timing circuit (4); the output end of the relay drive circuit (10) is connected to a heating element (12); the output end of the AND gate circuit (9) is connected to the input end of the relay drive circuit (10); the input end of the AND gate circuit (9) is connected to a liquid level detection circuit (7) and a tilt detection circuit (8).

2. The electric mosquito coil timing adjustable and protective circuit according to claim 1, characterized in that: The timing increase / decrease direction control circuit (1) comprises a light touch button S1, a pull-up resistor R9, a capacitor C4, a trigger U11A, an indicator light LED1, an indicator light LED3, a resistor R4, a resistor R18, a normally closed analog switch S2A and a pull-down resistor R2, wherein the light touch button S1 is connected to the pull-up resistor R9 and the capacitor C4, the capacitor C4 is connected to the trigger U11A, the trigger U11A is connected to the indicator light LED1 and the indicator light LED3, the indicator light LED1 is connected to the resistor R18, the indicator light LED3 is connected to the resistor R4, the right ends of the indicator light LED1 and the indicator light LED3 are connected to the normally closed analog switch S2A, and the right end of the normally closed analog switch S2A is connected to the pull-down resistor R2.

3. The electric mosquito coil timing adjustable and protective circuit according to claim 1, characterized in that: The timing duration setting circuit (2) comprises a light touch button S9, a pull-down resistor R15 and a capacitor C5, wherein the light touch button S9 is connected to the pull-down resistor R15 and the capacitor C5, and the other ends of the pull-down resistor R15 and the capacitor C5 are grounded.

4. The electric mosquito coil timing adjustable and protective circuit according to claim 1, characterized in that: The counting circuit (3) comprises a counter U1 and an OR gate device U6A, and the 3.2.6.7 pins of the counter U1 are connected to the OR gate device U6A.

5. The electric mosquito coil timing adjustable and protective circuit according to claim 1, characterized in that: The minute timing circuit (4) comprises a 555 timer A1, an analog switch S5, an analog switch S4, a resistor R1, a resistor R6, a resistor R7, a resistor R10, a resistor R11, a resistor R12, a resistor R13, a resistor R14, a resistor R5, a capacitor C2 and a capacitor C3.

6. The electric mosquito coil timing adjustable and protective circuit according to claim 1, characterized in that: The frequency division circuit (5) comprises U3, U4, U5A, U5C, and U5B, wherein the pin 14 of U3 is connected to the OUT output of A1, the pin 11 of U3 is connected to U5C, the input ends of U5C and U5B are connected to the pins 6 and 7 of U3, the output end of U5B is connected to the pin 14 of U4, and the pins 3 and 6 of U4 are connected to U5A; the trigger holding circuit (6) comprises Q1, R3, R16, and U11B, wherein the pin 11 of U11B is connected to Q1 and R16.

7. The electric mosquito coil timing adjustable and protective circuit according to claim 1, characterized in that: The liquid level detection circuit (7) comprises Q4 and R28; the tilt detection circuit (8) comprises R21, R22, C1, R24, U7A, R25 and S10.

8. The electric mosquito coil timing adjustable and protective circuit according to claim 1, characterized in that: The AND gate circuit (9) comprises D2, D3, and D4, and the D2, D3, and D4 are connected in parallel; the relay drive circuit (10) comprises LED4, resistor R19, resistor R20, transistor Q2, resistor R17, resistor R23, transistor Q3, diode D1, and relay K1.

9. The electric mosquito coil timing adjustable and protective circuit according to claim 1, characterized in that: The timer reset control circuit (11) comprises a resistor R27, a resistor R26, and a transistor Q5, wherein the input end of the transistor Q5 is connected to the resistor R27, and the output end of the resistor R27 is connected to the resistor R26.

Images