A toasting appliance and a handle detection circuit for a toasting appliance

Abstract

This utility model relates to the field of toaster technology, and discloses a toaster handle detection circuit and a toaster. The circuit includes: a power module, an AC input terminal, a handle trigger spring, a first rectifier diode, a second rectifier diode, a switching circuit, a control module, a first contact, and a second contact. The handle trigger spring is deformed by the handle, causing the first contact and the second contact to connect to the AC input terminal respectively. The power signal from the AC input terminal is applied to the two rectifier diodes through the connected first and second contacts, forming an intermittently pulled-down pulse waveform signal at the output of the switching circuit. The control module can determine that the contacts are closed by the intermittently pulled-down pulse waveform signal and can monitor the zero-crossing signal to confirm that the handle has been pressed down. By connecting the switching circuit to the handle trigger spring, the intermittently pulled-down pulse waveform signal is obtained through a small current, effectively reducing circuit power consumption and saving circuit board space compared with optocouplers.

Description

Technical Field

[0001] This utility model relates to the field of toaster technology, and in particular to a toaster handle detection circuit and a toaster. Background Technology

[0002] In existing technologies, most commercially available traditional toaster handle detection circuits require the use of optocouplers. When either the live or neutral wire after the handle contact is simultaneously connected, the optocoupler conducts and receives a zero-crossing signal to begin operation. However, optocouplers are relatively expensive and have poor thermal stability, exhibiting significant differences in current amplification at low and high temperatures. Under certain circumstances, this can lead to zero-crossing signal distortion, resulting in failure to detect the handle and the toaster malfunctioning. Furthermore, optocouplers have low current amplification, small current-limiting resistors, and consume a large amount of unnecessary power. Utility Model Content

[0003] The purpose of this invention is to provide a handle detection circuit for a toaster and a toaster itself, so as to solve one or more technical problems existing in the prior art, or at least provide a beneficial option or create conditions.

[0004] To achieve the above objectives, some embodiments of this application provide a handle detection circuit for a toaster, the circuit including: a power module, an AC input terminal, a handle trigger spring, a first rectifier diode, a second rectifier diode, a switching circuit, a control module, a first contact, and a second contact; The handle trigger spring is deformed by the handle so that the first contact and the second contact are respectively connected to the AC input terminal; The anode of the first rectifier diode is connected to the live wire of the AC input terminal through the first contact, and the anode of the second rectifier diode is connected to the neutral wire of the AC input terminal through the second contact. The cathodes of the first rectifier diode and the second rectifier diode are both connected to the input terminal of the switching circuit, the output terminal of the switching circuit is connected to the control module, and the power supply module is connected to the power supply terminal of the switching circuit. The switching circuit is used to receive the power signal after passing through the first contact and the second contact, and output a pulse waveform signal to the control module.

[0005] Furthermore, the power module includes: a step-down switching power supply circuit and a step-down power supply circuit; The input terminal of the step-down switching power supply circuit is connected to the AC input terminal, the output terminal of the step-down switching power supply circuit is connected to the input terminal of the step-down power supply circuit, and the output terminal of the step-down power supply circuit is connected to the power supply terminal of the switching circuit. The step-down switching power supply circuit is used to step down the power signal input to the AC input terminal and output a first supply voltage. The step-down power supply circuit is used to step down the first supply voltage and output a second supply voltage to the switching circuit.

[0006] Furthermore, the switching circuit includes: a switching device, a step-down resistor, a pull-up resistor, a pull-down resistor, a filter capacitor, and a current-limiting resistor; The base of the switching device is connected to the cathodes of the first rectifier diode and the second rectifier diode respectively through the step-down resistor; the collector of the switching device is connected to the power supply module through the pull-up resistor; and the collector of the switching device is connected to the control module through the current-limiting resistor. One end of the pull-down resistor is connected to the step-down resistor, one end of the filter capacitor is connected to the collector of the switching device, and the other end of the pull-down resistor, the other end of the filter capacitor, and the emitter of the switching device are all connected to ground.

[0007] Furthermore, the toaster's handle detection circuit also includes an electromagnet drive module; The power supply terminal of the electromagnet drive module is connected to the power supply module, the input terminal of the electromagnet drive module is connected to the control module, and the electromagnet drive module is connected to the handle. The electromagnet drive module is used to attract the handle, keeping the first contact and the second contact in a closed state.

[0008] Furthermore, the step-down switching power supply circuit includes: a rectifier bridge, a filter rectifier circuit, a first power chip, and a current-limiting voltage regulator circuit; The input terminal of the rectifier bridge is connected to the AC input terminal, the output terminal of the rectifier bridge is connected to the input terminal of the first power chip through the filter and rectification circuit, and the output terminal of the first power chip is connected to the input terminal of the buck power supply circuit through the current limiting and voltage regulating circuit.

[0009] Furthermore, the step-down power supply circuit includes: a second power chip and a voltage regulator and filter circuit; The input terminal of the second power chip is connected to the output terminal of the buck switching power supply circuit, the output terminal of the second power chip is connected to the input terminal of the voltage regulator and filter circuit, and the output terminal of the voltage regulator and filter circuit is connected to the power supply terminal of the switching circuit.

[0010] Furthermore, the electromagnet driving module includes: an electromagnet coil and a driving circuit; The input terminal of the drive circuit is connected to the output terminal of the control module, the output terminal of the drive circuit is connected to the electromagnet coil, the power supply terminal of the drive circuit is connected to the power module, and the electromagnet coil is connected to the handle.

[0011] Furthermore, the first power chip is a non-isolated buck switching power supply chip.

[0012] Furthermore, at least one step-down resistor is provided.

[0013] To achieve the above objectives, some embodiments of this application provide a toaster, including a handle detection circuit of a toaster according to some embodiments of this application.

[0014] The beneficial effects of this utility model are as follows: When the handle is pressed down, it squeezes the handle trigger spring, which connects the first and second contacts on the handle trigger spring. The power signal from the AC input terminal is loaded onto the two rectifier diodes through the connected first and second contacts, forming an intermittently pulled-down pulse waveform signal at the output of the switching circuit. The control module can determine the contact closure through the intermittently pulled-down pulse waveform signal, continuously monitor the zero-crossing signal, thereby confirming that the handle has been pressed down and starting the operation. By connecting the switching circuit to the handle trigger spring, the intermittently pulled-down pulse waveform signal is obtained through a small current, which effectively reduces the circuit power consumption. Compared with optocouplers, this solution saves circuit board space and provides convenience for the miniaturization design of toasters. Attached Figure Description

[0015] Figure 1 This is a partial circuit diagram of a toaster handle detection circuit provided in one embodiment of the present invention; Figure 2 This is a circuit diagram of the power module of the handle detection circuit of a toaster provided in one embodiment of the present invention; Figure 3 This is a circuit diagram of the button and display module of the handle detection circuit of a toaster provided in one embodiment of the present invention. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and should not be construed as limiting the scope of this invention.

[0017] It should be noted that although functional modules are divided in the diagram, in some cases, the modules can be divided differently from those in the system.

[0018] Furthermore, it is understood that the terms "first," "second," etc., used in this application may be used herein to describe various concepts, but unless specifically stated otherwise, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another. The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more features. For example, without departing from the scope of embodiments of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the words "if" or "when" as used herein may be interpreted as "in the event of," "when," or "in response to a determination."

[0019] In the description of this utility model, it should be noted that, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly. Those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model based on the specific content of the technical solution.

[0020] As described in the background section, in existing technologies, most conventional toaster handle detection circuits require the use of optocouplers. When either the live or neutral wire after the handle contact is simultaneously connected, the optocoupler is activated to obtain a zero-crossing signal and begin operation. However, optocouplers are relatively expensive and have poor thermal stability, exhibiting significant differences in current amplification at low and high temperatures. Under certain conditions, this can lead to zero-crossing signal distortion, resulting in the inability to detect the handle and the toaster malfunctioning. Furthermore, optocouplers have low current amplification, small current-limiting resistors, and consume a large amount of wasted power.

[0021] Reference Figure 1 and Figure 2 In some embodiments of this utility model, a toaster handle detection circuit includes: an AC input terminal, a handle trigger spring, a first rectifier diode D1, a second rectifier diode D2, a switching circuit 100, a control module 200, a power supply module 300, a first contact, and a second contact.

[0022] When the handle is pressed down, the handle trigger spring is squeezed, causing the handle trigger spring to deform. The first contact and the second contact are connected, and the first contact and the second contact are respectively connected to the live wire and the neutral wire on the AC input terminal. The voltage of the live wire and the neutral wire on the AC input terminal can be applied to the two rectifier diodes through the first contact and the second contact.

[0023] In this embodiment, the moving contact on the spring can be quickly connected to the stationary contact after the handle triggers the deformation of the spring. That is, the moving contact is connected to the first contact and the second contact respectively. Alternatively, a micro switch or a rocker switch or other methods can be used to make the spring deformed by the handle trigger, so that the first contact and the second contact are connected to the AC input terminal respectively. No specific limitation is made in this embodiment.

[0024] The anode of the first rectifier diode D1 is electrically connected to the first contact, and through the first contact, the anode of the first rectifier diode D1 can be electrically connected to the live wire of the AC input terminal. The cathode of the first rectifier diode D1 is electrically connected to the input terminal of the switching circuit 100.

[0025] The anode of the second rectifier diode D2 is connected to the second contact, through which the anode of the second rectifier diode D2 can be electrically connected to the neutral wire of the AC input terminal. The cathode of the second rectifier diode D2 is electrically connected to the input terminal of the switching circuit 100.

[0026] In other words, the two rectifier diodes are connected to the neutral and live wires respectively after the contacts. Pressing down the handle will squeeze the handle trigger spring, closing the two contacts and applying voltage to the two rectifier diodes.

[0027] The output terminal of the switching circuit 100 is electrically connected to the input terminal of the control module 200, and the power supply terminal of the switching circuit 100 is electrically connected to the output terminal of the power supply module 300.

[0028] The AC input terminal receives a power signal through two rectifier diodes and connects to the switching circuit 100, thus turning on the AC power. The switching circuit 100 receives this power signal and generates an intermittently pulled-low pulse waveform signal at its output terminal, which is then output to the control module 200. This pulse waveform signal can also be referred to as a zero-crossing signal. The control module 200 can determine that the handle is pressed down based on the pulse waveform signal, thus realizing the detection of the handle's state. In addition, after the handle is pressed down, if a zero-crossing signal is detected, the electromagnet drive module 400 is controlled to run, thereby starting the toaster.

[0029] Compared to the use of optocouplers in existing technologies, this solution reduces costs. Based on the amplification factor of the switching circuit 100, and by connecting the switching circuit 100 to the handle trigger spring, an intermittently pulled-down pulse waveform signal is obtained through a small current, effectively reducing system power consumption. This solution eliminates the need for electrical isolation, saves circuit board space, and facilitates the miniaturization design of toasters.

[0030] Reference Figure 1 and Figure 2 In some embodiments of this utility model, the power module 300 includes: a step-down switching power supply circuit 310 and a step-down power supply circuit 320.

[0031] The input terminal of the step-down switching power supply circuit 310 is electrically connected to the AC input terminal, the output terminal of the step-down switching power supply circuit 310 is electrically connected to the input terminal of the step-down power supply circuit 320, and the output terminal of the step-down power supply circuit 320 is electrically connected to the power supply terminal of the amplifier circuit.

[0032] When a power signal is input at the AC input terminal, the step-down switching power supply circuit 310 can initially step down the power signal input at the AC input terminal to output a first supply voltage. The step-down power supply circuit 320 can further step down the first supply voltage to output a second supply voltage to the amplifier circuit.

[0033] In one embodiment, reference is made to Figure 2 The step-down switching power supply circuit 310 includes: a rectifier bridge BD1, a filter rectifier circuit 311, a first power chip U2, and a current-limiting voltage regulator circuit 312.

[0034] The input terminal of rectifier bridge BD1 is electrically connected to the AC input terminal, the output terminal of rectifier bridge BD1 is electrically connected to the input terminal of filter rectifier circuit 311, the output terminal of filter rectifier circuit 311 is electrically connected to the input terminal of first power chip U2, the output terminal of first power chip U2 is electrically connected to the input terminal of current limiting voltage regulator circuit 312, and the output terminal of current limiting voltage regulator circuit 312 is electrically connected to the input terminal of buck power supply circuit 320.

[0035] The first power supply chip U2 is a non-isolated buck switching power supply chip. The filter and rectifier circuit 311 includes: a first inductor L1, a second inductor L2, a third capacitor C3, a fourth capacitor C4, a fourth diode D4, and a tenth resistor R10. The current-limiting and voltage-regulating circuit 312 includes: an eleventh resistor R11, a twelfth resistor R12, a fifth capacitor C5, a third inductor L3, a fifth diode D5, a sixth diode D6, a seventh capacitor C7, and an eighth capacitor C8.

[0036] In one embodiment, reference is made to Figure 2 The step-down power supply circuit 320 includes: a second power supply chip U3 and a voltage regulator and filter circuit 321.

[0037] The input terminal of the second power chip U3 is electrically connected to the output terminal of the step-down switching power supply circuit 310, that is, the input terminal of the second power chip U3 is electrically connected to the output terminal of the current limiting and voltage regulating circuit 312, the output terminal of the second power chip U3 is electrically connected to the input terminal of the voltage regulating and filtering circuit 321, and the output terminal of the voltage regulating and filtering circuit 321 is electrically connected to the power supply terminal of the amplifier circuit, so as to realize that the output terminal of the step-down power supply circuit 320 is electrically connected to the power supply terminal of the amplifier circuit.

[0038] The voltage regulator and filter circuit 321 includes: a fourth inductor L4, a thirteenth resistor R13, a tenth capacitor C10, and an eleventh capacitor C11.

[0039] Reference Figure 1 and Figure 2 In some embodiments of this utility model, the switching circuit 100 includes: a switching device Q1, a step-down resistor, a pull-down resistor R3, a pull-up resistor R4, a filter capacitor C1, and a current-limiting resistor R5.

[0040] One end of the step-down resistor is electrically connected to the cathode of the first rectifier diode D1 and the cathode of the second rectifier diode D2, respectively, so as to realize the electrical connection between the two rectifier diodes and the switching circuit 100. The other end of the step-down resistor is electrically connected to the base of the switching device Q1.

[0041] In one embodiment, at least one step-down resistor is provided, as shown in the reference. Figure 1 There are two step-down resistors (R1, R1). That is, the step-down resistor consists of one or more resistors. Its function is to allow the rectified current to flow through the resistors, then through the base and collector of the switching device Q1, and finally to GND. The maximum current estimate is Ib = V / R, where V is the rectified voltage and R is the total resistance of the series-connected step-down resistors. The step-down resistors allow most of the voltage to be absorbed by the resistors, reducing the voltage across the base of the switching device Q1.

[0042] Among them, reference Figure 1 The switching device Q1 can be a transistor, a MOSFET, or a high-frequency switching device. In this application, no restrictions are placed on the type of switching device Q1.

[0043] One end of the pull-up resistor R4 is electrically connected to the power module 300 to connect the output of the buck power supply circuit 320 to the power supply of the amplifier circuit. The other end of the pull-up resistor R4 is electrically connected to the collector of the switching device Q1. The pull-up resistor R4 can pull up the output voltage when the switching device Q1 is not turned on.

[0044] One end of the current-limiting resistor R5 is electrically connected to the input terminal of the control module 200, and the other end of the current-limiting resistor R5 is electrically connected to the collector of the switching device Q1. The current-limiting resistor R5 can limit the current between the switching device Q1 and the detection IO interface of the control module 200, preventing damage in case of malfunction of the control module 200.

[0045] The emitter of switching device Q1 is connected to ground. One end of pull-down resistor R3 is electrically connected to the step-down resistor, and the other end of pull-down resistor R3 is connected to ground. One end of filter capacitor C1 is connected to the collector of switching device Q1, and the other end of filter capacitor C1 is connected to ground.

[0046] The filter capacitor C1 can filter out occasional high-frequency pulse interference on the power supply signal, reducing interference to the normal operation of the control module 200.

[0047] In this embodiment, refer to Figure 1 When the handle is pressed down, it triggers the contact spring, connecting both the live and neutral wires. Current flows through either the first rectifier diode D1 or the second rectifier diode D2, then through the step-down resistor and the switching device Q1. After being stepped down by the step-down resistors (R1, R2), the current is connected to the base of the switching device Q1. The voltage between the live and neutral wires is a sinusoidal pulse, and the switching device Q1 is intermittently turned on. When it is on, it pulls down the collector voltage of the switching device Q1, thus generating a pulse waveform signal at the output terminal ZERO.

[0048] Furthermore, the zero-crossing signal is connected to the microcontroller control chip of the control module 200 through the current-limiting resistor R5. When the handle is pressed down, the AC power is turned on, which will generate an intermittently pulled-down pulse waveform signal. After the zero-crossing signal is detected, the electromagnet is turned on and the countdown begins.

[0049] Reference Figure 1 , Figure 2 and Figure 3 In some embodiments of this utility model, the circuit further includes: an electromagnet driving module 400, a button 500, and a display module 600.

[0050] The power supply terminal of the electromagnet drive module 400 is electrically connected to the power supply module 300, that is, the power supply terminal of the electromagnet drive module 400 is electrically connected to the output terminal of the step-down switching power supply circuit 310. The input terminal of the electromagnet drive module 400 is electrically connected to the output terminal of the control module 200. The electromagnet drive module 400 is connected to the handle. The electromagnet drive module 400 can also be electromagnetically connected to the handle.

[0051] The electromagnet drive module 400 can attract the handle, keeping the first and second contacts closed.

[0052] In one embodiment, the electromagnet drive module 400 includes an electromagnet coil 410 and a drive circuit 420.

[0053] The input terminal of the drive circuit 420 is electrically connected to the output terminal of the control module 200, the output terminal of the drive circuit 420 is electrically connected to the electromagnet coil 410, and the power supply terminal of the drive circuit 420 is electrically connected to the power supply module 300. That is, the power supply terminal of the electromagnet drive module 400 is electrically connected to the output terminal of the step-down switching power supply circuit 310. The electromagnet coil 410 is connected to the handle. The electromagnet coil 410 can be electromagnetically connected to the handle.

[0054] In this embodiment, when the handle is pressed down and a zero-crossing signal is detected, the control module 200 can control the drive circuit 420 to conduct, and the two ends of the electromagnet socket are connected to a 12V power supply. The electromagnet coil 410 starts to be energized and can hold the handle, keeping the contacts closed, so that the heating wire can be driven to heat up.

[0055] Button 500 is electrically connected to control module 200. Button 500 can respond to user input operations, allowing users to select functions, configure parameters, and start operation by operating button 500.

[0056] The display module 600 is electrically connected to the control module 200, and the display module 600 can indicate the working status and time progress.

[0057] In some embodiments of another aspect of the present invention, a toaster includes a handle detection circuit for the toaster in some embodiments of another aspect of the present invention.

[0058] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A handle detection circuit of a toaster, characterized by, include: Power module, AC input terminal, handle trigger spring, first rectifier diode, second rectifier diode, switching circuit, control module, first contact and second contact; The handle trigger spring is deformed by the handle so that the first contact and the second contact are respectively connected to the AC input terminal; The anode of the first rectifier diode is connected to the live wire of the AC input terminal through the first contact, and the anode of the second rectifier diode is connected to the neutral wire of the AC input terminal through the second contact. The cathodes of the first rectifier diode and the second rectifier diode are both connected to the input terminal of the switching circuit, the output terminal of the switching circuit is connected to the control module, and the power supply module is connected to the power supply terminal of the switching circuit. The switching circuit is used to receive the power signal after passing through the first contact and the second contact, and output a pulse waveform signal to the control module.

2. The toasting grill handle detection circuit of claim 1, wherein The power module includes: a step-down switching power supply circuit and a step-down power supply circuit; The input terminal of the step-down switching power supply circuit is connected to the AC input terminal, the output terminal of the step-down switching power supply circuit is connected to the input terminal of the step-down power supply circuit, and the output terminal of the step-down power supply circuit is connected to the power supply terminal of the switching circuit. The step-down switching power supply circuit is used to step down the power signal input to the AC input terminal and output a first supply voltage. The step-down power supply circuit is used to step down the first supply voltage and output a second supply voltage to the switching circuit.

3. The toasting grill handle detection circuit of claim 1, wherein The switching circuit includes: a switching device, a step-down resistor, a pull-up resistor, a pull-down resistor, a filter capacitor, and a current-limiting resistor; The base of the switching device is connected to the cathodes of the first rectifier diode and the second rectifier diode respectively through the step-down resistor; the collector of the switching device is connected to the power supply module through the pull-up resistor; and the collector of the switching device is connected to the control module through the current-limiting resistor. One end of the pull-down resistor is connected to the step-down resistor, one end of the filter capacitor is connected to the collector of the switching device, and the other end of the pull-down resistor, the other end of the filter capacitor, and the emitter of the switching device are all connected to ground.

4. The toaster handle detection circuit of claim 1, wherein Also includes: Electromagnet drive module; The power supply terminal of the electromagnet drive module is connected to the power supply module, the input terminal of the electromagnet drive module is connected to the control module, and the electromagnet drive module is connected to the handle. The electromagnet drive module is used to attract the handle, keeping the first contact and the second contact in a closed state.

5. The toasting grill handle detection circuit of claim 2, wherein The step-down switching power supply circuit includes: a rectifier bridge, a filter rectifier circuit, a first power chip, and a current-limiting voltage regulator circuit; The input terminal of the rectifier bridge is connected to the AC input terminal, the output terminal of the rectifier bridge is connected to the input terminal of the first power chip through the filter and rectification circuit, and the output terminal of the first power chip is connected to the input terminal of the buck power supply circuit through the current limiting and voltage regulating circuit.

6. The toasting grill handle detection circuit of claim 2, wherein The step-down power supply circuit includes: a second power chip and a voltage regulator and filter circuit; The input terminal of the second power chip is connected to the output terminal of the buck switching power supply circuit, the output terminal of the second power chip is connected to the input terminal of the voltage regulator and filter circuit, and the output terminal of the voltage regulator and filter circuit is connected to the power supply terminal of the switching circuit.

7. The handle detection circuit of the toaster according to claim 4, characterized in that, The electromagnet drive module includes: an electromagnet coil and a drive circuit; The input terminal of the drive circuit is connected to the output terminal of the control module, the output terminal of the drive circuit is connected to the electromagnet coil, the power supply terminal of the drive circuit is connected to the power module, and the electromagnet coil is connected to the handle.

8. The toasting grill handle detection circuit of claim 5, wherein, The first power chip is a non-isolated buck switching power supply chip.

9. The toasting grill handle detection circuit of claim 3, wherein At least one step-down resistor is provided.

10. A toaster characterized by Includes the handle detection circuit of the toaster as described in any one of claims 1 to 9.

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