CN115395496B - Hard switch electric tool start-up safety protection circuit - Google Patents
Hard switch electric tool start-up safety protection circuit Download PDFInfo
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- CN115395496B CN115395496B CN202211083245.6A CN202211083245A CN115395496B CN 115395496 B CN115395496 B CN 115395496B CN 202211083245 A CN202211083245 A CN 202211083245A CN 115395496 B CN115395496 B CN 115395496B
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H11/00—Emergency protective circuit arrangements for preventing the switching-on in case an undesired electric working condition might result
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
Abstract
The invention discloses a hard switch electric tool starting-up safety protection circuit which comprises a main switch S1, an optocoupler U1, a diode D1, a resistor R1, a capacitor C5, a resistor R2, a capacitor C1, a resistor R3, a resistor R4, a micro control unit MCU1, an auxiliary power supply circuit and a driving circuit, wherein the positive electrode of a light emitting diode in the optocoupler U1 is respectively connected with the resistor R1 and the capacitor C5, the other end of the capacitor C5 is grounded, and the other end of the resistor R1 is connected with the negative electrode of the diode D1.
Description
Technical Field
The invention relates to the technical field of electric tools, in particular to a hard-switch electric tool starting-up safety protection circuit.
Background
At present, most of electric tools with hard switches are not provided with self-protection devices, when the hard switches are in a closed state and are electrified, the machine can be started suddenly, at the moment, because an operator is still holding a plug, the machine is difficult to obtain complete control, a certain impact force caused by the sudden start of the machine is high, and huge potential safety hazards exist.
Disclosure of Invention
The invention aims to provide a hard-switch power-on safety protection circuit for an electric tool, which overcomes the defects in the prior art.
In order to achieve the above purpose, the present invention provides the following technical solutions:
the invention discloses a hard switch electric tool starting-up safety protection circuit which comprises a main switch S1, an optocoupler U1, a diode D1, a resistor R1, a capacitor C5, a resistor R2, a capacitor C1, a resistor R3, a resistor R4, a micro control unit MCU1, an auxiliary power supply circuit and a driving circuit, wherein the positive electrode of a light emitting diode in the optocoupler U1 is respectively connected with the resistor R1 and the capacitor C5, the other end of the capacitor C5 is grounded, the other end of the resistor R1 is connected with the negative electrode of the diode D1, the positive electrode of the diode D1 is connected with one end of the main switch, the negative electrode of a light emitting diode in the optocoupler U1 is respectively connected with the other end of the main switch S1 and one end of 220V alternating current, the collector of a phototriode in the optocoupler U1 is respectively connected with the resistor R2, the capacitor C1, the resistor R3 and one end of the resistor R4, the other end of the resistor C1 is connected with the auxiliary power supply circuit, the other end of the resistor R3 is grounded, the other end of the resistor R4 is connected with the micro control unit MCU1, and the power supply end and the control circuit are respectively connected with the auxiliary power supply circuit.
Preferably, the low-level signal controls the micro control unit MCU to control the electric tool to meet the starting condition, and the high-level signal controls the micro control unit MCU to control the electric tool not to meet the starting condition.
Preferably, the auxiliary power supply circuit includes an AC/DC step-down circuit, or a rectifying circuit plus a DC/DC step-down circuit.
Preferably, the driving circuit comprises a micro control unit MCU2, a micro control unit MCU3, an IGBT1, an IGBT2, an IGBT3, an IGBT4, and a resistor R5, wherein the micro control unit MCU2 and the micro control unit MCU3 are connected with the micro control unit MCU1, the micro control unit MCU2 is connected with the gate levels of the IGBT1 and the IGBT3 respectively, the micro control unit MCU3 is connected with the gate levels of the IGBT2 and the IGBT4 respectively, the collectors of the IGBT1 and the IGBT2 are connected with the auxiliary power supply circuit, the emitters of the IGBT1 and the IGBT2 are connected with the collectors of the IGBT3 and the IGBT4 respectively, a motor M is connected between the collectors of the IGBT3 and the IGBT4, the emitters of the IGBT3 and the IGBT4 are connected with one end of the resistor R5, and the other end of the resistor R5 is grounded.
Preferably, the micro control unit MCU2 and the micro control unit MCU3 control the IGBTs 2, 3 and 1, 4 to be respectively conducted, and change the current direction of the middle stator winding coil, thereby changing the magnetic field direction of the stator.
Preferably, a large capacity capacitor C6 is arranged in the driving circuit, so that the electric tool is controlled to have weak current in the power-off state.
Preferably, the micro control unit MCU1 is a SN8P2712 single chip microcomputer, the resistor R4 is connected to the detection end of the micro control unit MCU1, and the driving circuit is connected to the control end of the micro control unit MCU 1.
The invention has the beneficial effects that: the invention relates to a hard switch electric tool starting-up safety protection circuit, which solves the problem that in the prior art, when a hard switch is in a closed state, a power-up electric tool is started up in a non-control state, and is safe and reliable.
Drawings
FIG. 1 is a schematic circuit diagram of an embodiment of the present invention;
FIG. 2 is a flowchart of a chip determination process according to an embodiment of the present invention.
Detailed Description
The present invention will be further described in detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the detailed description and specific examples, while indicating the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. In addition, in the following description, descriptions of well-known structures and techniques are omitted so as not to unnecessarily obscure the present invention.
As shown in fig. 1, the embodiment of the invention provides a hard switch electric tool start-up safety protection circuit, which comprises a main switch S1, an optocoupler U1, a diode D1, a resistor R1, a capacitor C5, a resistor R2, a capacitor C1, a resistor R3, a resistor R4, a micro control unit MCU1, an auxiliary power circuit and a driving circuit, wherein the positive electrode of a light emitting diode in the optocoupler U1 is respectively connected with the resistor R1 and the capacitor C5, the other end of the capacitor C5 is grounded, the other end of the resistor R1 is connected with the negative electrode of the diode D1, the positive electrode of the diode D1 is connected with one end of the main switch, the negative electrode of a light emitting diode in the optocoupler U1 is respectively connected with the other end of the main switch S1 and one end of 220V alternating current, the collector of a phototriode in the optocoupler U1 is respectively connected with the resistor R2, the capacitor C1, the resistor R3 and one end of the resistor R4, the other ends of the resistor R2 and the capacitor C1 are connected with the auxiliary power circuit, the other end of the resistor R3 is grounded, the other end of the resistor R4 is connected with the micro control unit 1, and the power supply circuit and the control circuit are respectively connected with the micro control unit MCU 1.
In this embodiment, the auxiliary power circuit is an AC/DC step-down circuit, or a rectifier circuit plus a DC/DC step-down circuit may be used, and the voltage at the output terminal VCC of the auxiliary power circuit is 5V; the micro control unit MCU1 adopts an SN8P2712 singlechip, the resistor R4 is connected with the detection end of the micro control unit MCU1, the driving circuit is connected with the control end of the micro control unit MCU1, and the auxiliary power circuit is connected with the MCU1_VCC end of the micro control unit MCU1 to supply power to the micro control unit MCU1; when the AC220V is electrified, if the main switch S1 is closed, the light emitting diode in the optocoupler U1 is short-circuited by the main switch S1 so as not to be conducted, the phototriode in the optocoupler U1 is not conducted, the output end VCC of the auxiliary power supply circuit is grounded through a resistor R2 and a resistor R3, the resistor R2 and the resistor R3 divide the output voltage VCC, the voltage of the detection end of the micro control unit MCU1 is at a high level at the moment, the electric tool does not meet the starting condition, the control end of the micro control unit MCU1 does not provide an electric signal for starting the driving circuit, and the driving circuit is not started; when the AC220V is electrified, if the main switch S1 is disconnected, the light emitting diode in the optocoupler U1 is conducted, then the phototriode in the optocoupler U1 is conducted, the output end VCC of the auxiliary power supply circuit is grounded through the resistor R2, the voltage of the detection end of the micro control unit MCU1 is pulled down, the voltage is at a low level at the moment, the electric tool meets the starting condition, the control end of the micro control unit MCU1 provides an electric signal for starting the driving circuit, the auxiliary power supply supplies power for the driving circuit, and the driving circuit is started normally.
The driving circuit comprises a micro control unit MCU2, a micro control unit MCU3, an IGBT1, an IGBT2, an IGBT3, an IGBT4 and a resistor R5, wherein the micro control unit MCU2 and the micro control unit MCU3 are connected with the micro control unit MCU1, the micro control unit MCU2 is respectively connected with the gates of the IGBT1 and the IGBT3, the micro control unit MCU3 is respectively connected with the gates of the IGBT2 and the IGBT4, the collectors of the IGBT1 and the IGBT2 are respectively connected with the auxiliary power supply circuit, the emitters of the IGBT1 and the IGBT2 are respectively connected with the collectors of the IGBT3 and the IGBT4, a motor M is connected between the collectors of the IGBT3 and the IGBT4, the emitters of the IGBT3 and the IGBT4 are respectively connected with one end of the resistor R5, and the other end of the resistor R5 is grounded.
The low-level signal controls the micro control unit MCU1 to control the electric tool to meet the starting condition, and the high-level signal controls the micro control unit MCU1 to control the electric tool not to meet the starting condition.
As shown in fig. 2, the determining process of the MCU1 specifically includes: after being electrified, the micro control unit MCU1 detects whether the chip pin connected with the resistor R4 is at a high level, if so, the power-on condition is met, the micro control unit MCU1 drives the micro control unit MCU2 and the micro control unit MCU3, and the driving circuit is normally started and started; if the pin is at a high level, the control end of the micro control unit MCU1 does not provide an electric signal for starting up the drive circuit, and the drive circuit is not started up.
The driving circuit is internally provided with a large-capacity capacitor C6, so that the electric tool is controlled to be in a power-off state, and weak current exists in the driving circuit.
In addition, the process of controlling the motor to start by the driving circuit specifically comprises the following steps: the auxiliary power supply circuit supplies power to the driving circuit, the MCU1 controls the MCU2 and the MCU3 respectively, the MCU2 controls the IGBT1 and the IGBT3 to be conducted alternately, the MCU3 controls the IGBTQ2 and the IGBT4 to be conducted alternately, wherein when the IGBT1 is controlled to be conducted, the IGBT4 is controlled to be conducted, the IGBT2 and the IGBT3 are not controlled to be conducted, when the IGBT2 is controlled to be conducted, the IGBT3 is controlled to be conducted, the IGBT1 and the IGBT4 are not controlled to be conducted, M in the figure represents a motor, a motor stator is wound by an enameled wire, the head end and the tail end of the enameled wire respectively correspond to the left end and the right end of the motor M in the figure, the current flow direction of the stator is controlled through four IGBTs (insulated gate bipolar transistors), and therefore the brushless motor stator is controlled to generate an alternating magnetic field, and the rotor is controlled to rotate.
In this embodiment:
diode D1: the function is one-way conduction, prevents current from flowing back and can only flow from one direction;
resistance R1: is a voltage dividing resistor, so that the optocoupler is at normal working voltage;
resistor R2 and resistor R3: the voltage of the two ends of the capacitor C1 is adjusted by an up-down voltage-adjusting resistor;
resistor R4: is a buffer resistor of the MCU1 and is used for protecting the MCU1;
capacitance C1: the function is energy storage delay, when the switch is closed, the low level is kept for a certain time to delay 5V, and the starting condition is reached;
capacitance C5: the energy storage element is used for providing energy for the optocoupler device, and the main function is filtering, so that the output of the voltage stabilizer can be homogenized, the load demand is reduced, and the current is more stable;
and (2) a main switch: simulating the open and closed states of a hard switch on the power tool;
when the main switch is turned on, the driving circuit is electrified, the auxiliary power supply circuit leads 5V voltage to the resistor R2 and the capacitor C1, the main switch is turned off, the driving circuit is not electrified, and the 5V of the detection end is changed into 0V.
The circuit principle of the invention is as follows:
when the main switch is in an on state, the main switch is electrified, a weak current in the driving circuit conducts a diode D1, a resistor R1, a capacitor C5 and an internal diode of the optocoupler, at the moment, the diode in the optocoupler U1 emits light, the CE end of the triode is controlled to conduct, at the moment, the VCC voltage of the auxiliary power supply circuit is grounded through the resistor R2 and the optocoupler U1, namely, the MCU1 detects a low level and meets the starting condition; then the main switch is closed again, and the capacitor C1 starts to store energy and delay after the main switch is closed, so that the high level is delayed, the MCU1 keeps a low level for a certain time, a starting condition for a period of time is maintained, and after the electric tool is started, the MCU1 does not influence the starting condition.
When the main switch is in a closed state, the power is supplied, but at the moment, the two ends of the A and the B are short-circuited by the main switch, at the moment, the optocoupler U1 does not work, at the moment, the CE end of the optocoupler U1 is not connected, in addition, at the moment, the VCC voltage of the auxiliary power supply circuit is grounded through the resistor R2 and the resistor R3, and the MCU1 does not accord with the starting condition when the MCU1 detects high level due to the voltage division of the resistor R3, and the electric tool does not work; the main switch needs to be closed, so that the whole circuit is powered on when the main switch is in an open state, and then the main switch is closed, and the power-on is performed according to the principle.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, or alternatives falling within the spirit and principles of the invention.
Claims (6)
1. The utility model provides a hard switch electric tool start-up safety protection circuit, its characterized in that includes main switch S1, opto-coupler U1, diode D1, resistance R1, electric capacity C5, resistance R2, electric capacity C1, resistance R3, resistance R4, little control unit MCU1, auxiliary power supply circuit and drive circuit, the positive pole of emitting diode connects resistance R1 and electric capacity C5 respectively in the opto-coupler U1, electric capacity C5 other end ground connection, diode D1 negative pole is connected to the diode D1 positive pole is connected with main switch one end, the light emitting diode negative pole is connected main switch S1 other end and 220V alternating current one end respectively in the opto-coupler U1, phototriode collecting electrode in the opto-coupler U1 connects resistance R2, electric capacity C1, resistance R3, resistance R4 one end respectively, resistance R2 and electric capacity C1 other end with auxiliary power supply circuit connection, resistance R3 other end ground connection little control unit MCU1, drive circuit' S other end and control end respectively with the power supply and control unit D1 negative pole, little electric capacity is in the drive circuit is in the little power supply circuit state under the drive circuit, little electric capacity is in MCU 6.
2. The hard-switching power tool power-on safety protection circuit of claim 1, wherein: the low-level signal controls the micro control unit MCU1 to control the electric tool to meet the starting condition, and the high-level signal controls the micro control unit MCU1 to control the electric tool not to meet the starting condition.
3. The hard-switching power tool power-on safety protection circuit of claim 1, wherein: the auxiliary power circuit comprises an AC/DC voltage reduction circuit or a rectifying circuit plus a DC/DC voltage reduction circuit.
4. The hard-switching power tool power-on safety protection circuit of claim 1, wherein: the driving circuit comprises a micro control unit MCU2, a micro control unit MCU3, an IGBT1, an IGBT2, an IGBT3, an IGBT4 and a resistor R5, wherein the micro control unit MCU2 and the micro control unit MCU3 are connected with the micro control unit MCU1, the micro control unit MCU2 is respectively connected with the gate level connection of the IGBT1 and the IGBT3, the micro control unit MCU3 is respectively connected with the gate level connection of the IGBT2 and the IGBT4, the collectors of the IGBT1 and the IGBT2 are respectively connected with the auxiliary power supply circuit, the emitters of the IGBT1 and the IGBT2 are respectively connected with the collectors of the IGBT3 and the IGBT4, a motor M is connected between the collectors of the IGBT3 and the IGBT4, the emitters of the IGBT3 and the IGBT4 are respectively connected with one end of the resistor R5, and the other end of the resistor R5 is grounded.
5. The hard switching power tool power-on safety protection circuit according to claim 4, wherein: the micro control unit MCU2 and the micro control unit MCU3 control the IGBT2, the IGBT3, the IGBT1 and the IGBT4 to be respectively conducted, and change the current direction of the middle stator winding coil, thereby changing the magnetic field direction of the stator.
6. The hard-switching power tool power-on safety protection circuit of claim 1, wherein: the micro control unit MCU1 is a SN8P2712 singlechip, the resistor R4 is connected with the detection end of the micro control unit MCU1, and the driving circuit is connected with the control end of the micro control unit MCU 1.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202211083245.6A CN115395496B (en) | 2022-09-06 | 2022-09-06 | Hard switch electric tool start-up safety protection circuit |
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| CN202211083245.6A CN115395496B (en) | 2022-09-06 | 2022-09-06 | Hard switch electric tool start-up safety protection circuit |
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| CN115395496A CN115395496A (en) | 2022-11-25 |
| CN115395496B true CN115395496B (en) | 2023-05-23 |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108162079A (en) * | 2017-12-25 | 2018-06-15 | 常州格力博有限公司 | Electric tool |
| CN208262520U (en) * | 2018-05-15 | 2018-12-21 | 南京德朔实业有限公司 | Electric tool and angle grinder |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2833977Y (en) * | 2005-10-01 | 2006-11-01 | 吴如喜 | Magnetic card line controller |
| CN207217347U (en) * | 2017-07-14 | 2018-04-10 | 浙江佳奔电子有限公司 | Button switch with power-off restarting defencive function |
| CN207475180U (en) * | 2018-01-09 | 2018-06-08 | 深圳市乐祺微电子科技有限公司 | A kind of electric tool safety starting protection circuit |
| CN208078904U (en) * | 2018-03-21 | 2018-11-09 | 精进电动科技股份有限公司 | A kind of low-voltage power supply circuit |
| CN109361205B (en) * | 2018-12-10 | 2023-09-26 | 深圳和而泰智能控制股份有限公司 | Power-down protection circuit and electric tool |
| CN111431464A (en) * | 2019-01-10 | 2020-07-17 | 南京德朔实业有限公司 | Electric tool |
| CN210577798U (en) * | 2019-09-10 | 2020-05-19 | 深圳和而泰智能控制股份有限公司 | Power-on protection circuit and electric tool |
| CN110932539A (en) * | 2019-12-13 | 2020-03-27 | 常州格力博有限公司 | High-voltage driver switching system and switching method thereof |
| CN112952759B (en) * | 2021-02-05 | 2022-10-28 | 格力博(江苏)股份有限公司 | Power-on protection circuit and electric tool |
| CN114221581A (en) * | 2021-12-03 | 2022-03-22 | 张家港华捷电子有限公司 | Electric tool driving circuit adaptable to various starting modes |
| CN216819465U (en) * | 2022-01-24 | 2022-06-24 | 天宝精密科技(惠州市)有限公司 | Power-on protection circuit based on electric tool |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108162079A (en) * | 2017-12-25 | 2018-06-15 | 常州格力博有限公司 | Electric tool |
| CN208262520U (en) * | 2018-05-15 | 2018-12-21 | 南京德朔实业有限公司 | Electric tool and angle grinder |
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