A trigger start circuit and power tool controller

Abstract

The application discloses a trigger starting circuit and an electric tool controller, relates to the technical field of starting control, and comprises a first controllable switch module, a low-voltage conduction module, a switch module, a first capacitor and an energy release module, the second end of a main switch is connected with the first end of the low-voltage conduction module, the control end of the first controllable switch module is connected with the second end of the low-voltage conduction module, the control end of the low-voltage conduction module is connected with the other end of the first capacitor, and when the main switch is restarted after being turned off, the first capacitor does not need to be discharged to 0, but trigger starting is realized by using the pressure difference principle, namely, after the main switch is closed again, as long as the voltage output by the second end of the main switch minus the voltage between the two ends of the first capacitor is not less than the conduction voltage drop of the low-voltage conduction module, the low-voltage conduction module can be conducted, the first controllable switch module is conducted, and the power supply module is started. The circuit can realize the rapid starting of the electric tool controller after the electric tool controller is turned off, is convenient for practical application, and improves the user experience.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of starting control, in particular to a trigger starting circuit and a power tool controller. BACKGROUND

[0002] For the power tool controller, in order to realize the trigger starting of the main chip therein, and then control other components, the trigger starting circuit as shown in the figure is usually adopted, the main switch is closed, the output voltage of the power supply charges the capacitor C1, the charging current of the capacitor C1 makes the NPN type transistor Q2 be triggered to conduct, and then makes the PNP type transistor Q1 conduct, the output voltage of the power supply is output to the main chip through the conducted transistor Q1, the main chip is powered and the starting is completed, and the self-locking circuit is self-locked to ensure the above power supply of the main chip. Figure 1

[0003] However, the power tool controller also includes a motor, in order to absorb the reverse current of the motor to prevent the reverse current from causing impact on other devices, the capacitor C2 needs to be set, and the size of the capacitor C2 is usually much larger than that of the capacitor C1, for example, the capacitor C2 is a 220 microfarad capacitor, and the capacitor C1 is only a 1 microfarad capacitor. The capacitor C2 cannot be removed due to the above-mentioned function setting, which makes the discharge time of the capacitor C2 and the capacitor C1 longer, and the capacitor C2 will also power the capacitor C1, so only when the capacitor C1 is almost discharged to 0, that is, the voltage between the two ends is almost 0, the main switch is closed, and the charging current of the capacitor C1 can trigger the NPN type transistor Q2, so that the power tool controller cannot be started quickly after being turned off, affecting the actual application and user experience. Figure 1 SUMMARY

[0004] The purpose of the present application is to provide a trigger starting circuit and a power tool controller, which realizes trigger starting by using the pressure difference principle. Compared with the prior art, the circuit can realize the quick starting of the power tool controller after being turned off, is more convenient for actual application, and improves the user experience.

[0005] To solve the above technical problems, the present application provides a trigger starting circuit, which comprises a first controllable switch module, a low-voltage conduction module, a switch module, a first capacitor and an energy discharge module.

[0006] ​​The output positive terminal of the power supply is connected with the first terminal of the first controllable switch module and the first terminal of the main switch, the second terminal of the main switch is connected with one end of the second capacitor, the first terminal of the low-voltage conduction module, one end of the energy release module and the second terminal of the switch module respectively, and the other end of the second capacitor is grounded; one end of the first capacitor is connected with the other end of the energy release module and the connection end is grounded;

[0007] The first terminal of the switch module is connected with the control terminal of the low-voltage conduction module and the other end of the first capacitor respectively, for conducting between the first terminal and the second terminal when the main switch is turned off, and for turning off between the first terminal and the second terminal when the main switch is turned on.

[0008] The second terminal of the first controllable switch module is connected with the power supply terminal of the to-be-powered module, and the control terminal is connected with the second terminal of the low-voltage conduction module, for conducting when the main switch is turned on and the low-voltage conduction module conducts.

[0009] The low-voltage conduction module is used for conducting when the voltage difference between the first terminal and the control terminal is not less than the conduction voltage drop of the low-voltage conduction module, and is used for turning off when the voltage difference is less than the conduction voltage drop.

[0010] Preferably, further comprising:

[0011] A self-locking module, the input terminal is connected with the first output terminal of the to-be-powered module, and the output terminal is connected with the control terminal of the first controllable switch module.

[0012] The to-be-powered module is used for sending a control signal to the control terminal of the first controllable switch module to keep the first controllable switch module conducting when the first controllable switch module conducts.

[0013] Preferably, the self-locking module comprises:

[0014] A second resistor, one end of which is used as the output terminal of the self-locking module.

[0015] A first diode, the cathode of which is connected with the other end of the second resistor, and the anode of which is used as the input terminal of the self-locking module for current anti-reversal.

[0016] Preferably, the switch module comprises a second diode, the anode of which is used as the first terminal of the switch module, and the cathode of which is used as the second terminal of the switch module.

[0017] Preferably, the first controllable switch module comprises:

[0018] A first NPN triode, the base of which is used as the control terminal of the first controllable switch module, and the emitter of which is grounded.

[0019] A first PNP triode, the base thereof is connected with the collector of the first NPN triode, the emitter thereof is the first end of the first controllable switch module, and the collector thereof is the second end of the first controllable switch module.

[0020] Preferably, the low-voltage conduction module further comprises a third resistor.

[0021] The third resistor is arranged between the second end of the low-voltage conduction module and the control end of the first controllable switch module, one end of the third resistor is connected with the second end of the low-voltage conduction module, and the other end of the third resistor is connected with the control end of the first controllable switch module.

[0022] Preferably, the low-voltage conduction module comprises:

[0023] A second PNP triode, the base thereof is the control end of the low-voltage conduction module, the emitter thereof is the first end of the low-voltage conduction module, and the collector thereof is the second end of the low-voltage conduction module.

[0024] Preferably, the low-voltage conduction module further comprises:

[0025] A fourth resistor, one end of the fourth resistor is connected with the base of the second PNP triode, and the other end of the fourth resistor is the second end of the low-voltage conduction module.

[0026] Preferably, the low-voltage conduction module further comprises:

[0027] A third diode, the cathode of the third diode is connected with the emitter of the second PNP triode, and the anode of the third diode is the first end of the low-voltage conduction module, for preventing current from reversing.

[0028] To solve the above technical problems, the application further provides an electric tool controller, comprising a main switch, a to-be-powered module and a second capacitor, and further comprising the trigger starting circuit.

[0029] The application provides a trigger starting circuit and a power tool controller, which comprises a first controllable switch module, a low-voltage conduction module, a switch module, a first capacitor and a energy release module, the second end of a main switch is connected with the first end of the low-voltage conduction module, the control end of the first controllable switch module is connected with the second end of the low-voltage conduction module; the control end of the low-voltage conduction module is connected with the other end of the first capacitor, on the basis of the above connection relationship, when the main switch is restarted after being turned off, the trigger is not realized by waiting for the first capacitor to be discharged to 0 and then using the charging current, but the trigger is realized by using the pressure difference principle, specifically, after the main switch is turned off and then closed, as long as the voltage output by the second end of the main switch minus the voltage between the two ends of the first capacitor is not less than the conduction voltage drop of the low-voltage conduction module, the low-voltage conduction module will be turned on, the voltage output by the second end of the main switch will make the first controllable switch module turned on, and the power supply module can be started. Compared with the prior art, the circuit can realize the fast starting of the power tool controller after the power tool controller is turned off, is more convenient for practical application, and improves the user experience. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the prior art and embodiments. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0031] Figure 1 It is a structural schematic diagram of a trigger starting circuit in the prior art.

[0032] Figure 2 It is a structural schematic diagram of a trigger starting circuit provided by the present application. DETAILED DESCRIPTION

[0033] The core of the present application is to provide a trigger starting circuit and a power tool controller, which realizes trigger starting by using the pressure difference principle. Compared with the prior art, the circuit can realize the fast starting of the power tool controller after the power tool controller is turned off, is more convenient for practical application, and improves the user experience.

[0034] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will combine the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without any creative effort belong to the protection scope of the present application.

[0035] Please refer to Figure 1 and Figure 2 , Figure 1A structural schematic diagram of a trigger starting circuit in the prior art, Figure 2 A structural schematic diagram of a trigger starting circuit provided by the present application.

[0036] The trigger starting circuit comprises a first controllable switch module 1, a low-voltage conduction module 2, a switch module 3, a first capacitor C1 and a energy dissipation module 4.

[0037] The output positive terminal of the power supply is connected with the first terminal of the first controllable switch module 1 and the first terminal of the main switch, the second terminal of the main switch is connected with one end of the second capacitor C2, the first terminal of the low-voltage conduction module 2, one end of the energy dissipation module 4 and the second terminal of the switch module 3 respectively, and the other end of the second capacitor C2 is grounded; one end of the first capacitor C1 is connected with the other end of the energy dissipation module 4 and the connection end is grounded.

[0038] The first terminal of the switch module 3 is connected with the control terminal of the low-voltage conduction module 2 and the other end of the first capacitor C1 respectively, for conducting between the first terminal and the second terminal when the main switch is turned off, and for turning off between the first terminal and the second terminal when the main switch is turned on.

[0039] The second terminal of the first controllable switch module 1 is connected with the power supply terminal of the to-be-powered module, and the control terminal is connected with the second terminal of the low-voltage conduction module 2, for conducting when the main switch is turned on and the low-voltage conduction module 2 is turned on.

[0040] The low-voltage conduction module 2 is used for conducting when the voltage difference between the first terminal and the control terminal is not less than the conduction voltage drop of the low-voltage conduction module 2, and is used for turning off when the voltage difference is less than the conduction voltage drop.

[0041] The main chip in the electric tool controller can only be controlled after being started, and in order to realize the trigger starting of the main chip, the prior art usually adopts the trigger starting circuit as shown in the figure, but after the main switch is turned off, it needs to wait until the voltage across the capacitor C1 almost drops to 0 before restarting, that is, when the voltage across the capacitor C1 is almost 0, the trigger conduction of the NPN type transistor Q2 can be realized by using the charging current of the capacitor C1, so that the electric tool controller cannot realize fast starting. Figure 1

[0042] Specifically, the trigger starting circuit can be specifically applied to the electric tool controller, and the circuit connection is shown in the above description, which will not be described here again, and more details can be referred to the figure. Figure 2 The to-be-powered module is the main chip, and the second capacitor C2 is an absorption capacitor used for absorbing the motor reverse current in the electric tool controller. The circuit principle is described as follows.

[0043] ​By selection, the turn-on voltage drop of the low-voltage turn-on module 2 is set to be low (e.g. 1.4V), so that when the entire power tool controller is powered on for the first time (i.e. at this time, the voltage across the first capacitor C1 and the second capacitor C2 is 0), after the main switch is closed, the voltage difference between the first end (i.e. point A shown in Figure 2 Figure 2 ) of the low-voltage turn-on module 2 and the control end (i.e. point B shown in Figure 2 ) thereof is necessarily greater than the turn-on voltage drop, the low-voltage turn-on module 2 is turned on between the first end and the second end, and then the first controllable switch module 1 is turned on between the first end and the second end, and the power supply end of the to-be-powered module is powered on; subsequently, if the main switch is opened and then closed again, as long as the voltage difference between the first end and the control end of the low-voltage turn-on module 2 is equal to the turn-on voltage drop, the power supply end of the to-be-powered module can be powered on, and then the power tool controller can be started. Specifically, taking the turn-on voltage drop as 1.4V and assuming that the voltage of point A is 20V when the main switch is closed as an example, only the voltage across the first capacitor C1 needs to be not greater than 18.6V, and then the starting can be realized, and then the rapid power-on of the entire power tool controller can be realized, and the problem that the power tool controller cannot be started quickly in a short time after being powered off is solved.

[0044] It should be further noted that the energy release module 4 can specifically include an eleventh resistor R11, one end of the eleventh resistor R11 is connected with the second end of the switch module, and the other end of the eleventh resistor R11 is grounded. In addition, the resistance value of the eleventh resistor R11 can be 2 megaohms.

[0045] In addition, the size of the first capacitor C1 can be 1 microfarad, and the size of the second capacitor C2 can be 220 microfarads; a fourth diode for current anti-reversal and isolation can also be arranged, the cathode of the fourth diode is connected with the first end of the first controllable switch module 1, and the anode of the fourth diode is connected with the first end of the low-voltage turn-on module 2, as shown in Figure 2 .

[0046] In summary, the application provides a trigger starting circuit. On the basis of the above connection relationship, when the main switch is opened and then closed again, the first capacitor C1 does not need to be discharged to 0 and then the trigger is realized by using the charging current, but the trigger starting is realized by using the pressure difference principle. Specifically, after the main switch is opened and then closed again, as long as the voltage output by the second end of the main switch minus the voltage across the first capacitor C1 is not less than the turn-on voltage drop of the low-voltage turn-on module 2, the low-voltage turn-on module 2 is turned on, and then the first controllable switch module 1 is turned on by the voltage output by the second end of the main switch, and then the to-be-powered module can be started. Compared with the prior art, the circuit can realize the rapid starting of the power tool controller after the power tool controller is powered off, is more convenient for practical application, and improves the user experience.

[0047] On the basis of the above embodiment:

[0048] As a preferred embodiment, further comprising:

[0049] The self-locking module 5 is connected with the first output end of the to-be-powered module and the control end of the first controllable switch module 1.

[0050] The to-be-powered module is configured to send a control signal to the control end of the first controllable switch module 1 when the first controllable switch module 1 is turned on, so as to keep the first controllable switch module 1 turned on.

[0051] In the embodiment, the inventor further considers that the low-voltage turn-on module 2 will be turned off after being turned on for a period of time, which affects the power supply of the to-be-powered module. Therefore, the self-locking is performed at the moment when the to-be-powered module is powered, so as to ensure the power supply of the to-be-powered module. For details, refer to the foregoing description, which will not be repeated here.

[0052] As a preferred embodiment, the self-locking module 5 comprises:

[0053] The first resistor R1 has one end as the output end of the self-locking module 5.

[0054] The first diode D2 has a cathode connected with the other end of the first resistor R1 and an anode as the input end of the self-locking module 5, and is configured to prevent current from reversing.

[0055] In the embodiment, the self-locking module 5 comprises the first resistor R1 and the first diode D2. For details of the connection mode, refer to the foregoing description and the accompanying drawings. Figure 2 In addition, the resistance value of the first resistor R1 includes but is not limited to 49.9 kilo-ohms.

[0056] As a preferred embodiment, the switch module 3 comprises a second diode D1C, the anode of the second diode D1C is the first end of the switch module 3, and the cathode of the second diode D1C is the second end of the switch module 3.

[0057] In the embodiment, the switch module 3 can be the second diode D1C, considering that the diode has the advantages of small size, low price and unidirectional conduction. For details of the connection mode, refer to the foregoing description and the accompanying drawings. Figure 2

[0058] As a preferred embodiment, the first controllable switch module 1 comprises:

[0059] The first NPN-type triode Q4 has a base as the control end of the first controllable switch module 1 and an emitter connected with the ground.

[0060] ​The first PNP type transistor Q3 has its base connected to the collector of the first NPN type transistor Q4, its emitter as the first end of the first controllable switch module 1, and its collector as the second end of the first controllable switch module 1.

[0061] In this embodiment, it is shown that the first controllable switch module 1 can include the first NPN type transistor Q4 and the first PNP type transistor Q3, and the specific connection mode is shown in the above description. Figure 2

[0062] It should be further noted that, in order to ensure the reliable and safe conduction of the first PNP type transistor Q3, a fifth resistor R5 and a sixth resistor R6 can also be provided. One end of the fifth resistor R5 is connected to the emitter of the first PNP type transistor Q3, the other end of the fifth resistor R5 is connected to the base of the first PNP type transistor Q3 and one end of the sixth resistor R6, and the other end of the sixth resistor R6 is connected to the collector of the first NPN type transistor Q4. The sixth resistor R6 is used for current limiting, and the specific connection mode is shown in the above description. Figure 2

[0063] As a preferred embodiment, a third resistor R8 is further included.

[0064] The third resistor R8 is arranged between the second end of the low-voltage conduction module 2 and the control end of the first controllable switch module 1, one end of the third resistor R8 is connected to the second end of the low-voltage conduction module 2, and the other end of the third resistor R8 is connected to the control end of the first controllable switch module 1.

[0065] In this embodiment, the inventor further considers that, in order to trigger the safe operation of the starting circuit, a third resistor R8 can also be provided for current limiting, and the specific connection mode is shown in the above description. Figure 2

[0066] As a preferred embodiment, the low-voltage conduction module 2 includes:

[0067] The second PNP type transistor Q5 has its base as the control end of the low-voltage conduction module 2, its emitter as the first end of the low-voltage conduction module 2, and its collector as the second end of the low-voltage conduction module 2.

[0068] ​​​In the embodiment, the low-voltage conduction module 2 can include a second PNP-type triode Q5, and the conduction voltage drop of the second PNP-type triode Q5 is generally 0.7 V, so that the execution logic of the low-voltage conduction module 2 can be simply and reliably realized, the effectiveness of the entire trigger starting circuit is ensured, and the rapid restart of the entire electric tool controller is realized.

[0069] In addition, in order to ensure the safe and reliable conduction of the second PNP-type triode Q5, a ninth resistor R9 can also be arranged, one end of the ninth resistor R9 is connected with the emitter of the second PNP-type triode Q5, and the other end of the ninth resistor R9 is connected with the base of the second PNP-type triode Q5. The resistance value of the ninth resistor R9 includes but is not limited to 330 kΩ.

[0070] As a preferred embodiment, the low-voltage conduction module 2 further includes:

[0071] A fourth resistor R10, one end of which is connected with the base of the second PNP-type triode Q5, and the other end of which is used as the second end of the low-voltage conduction module 2.

[0072] In the embodiment, the low-voltage conduction module 2 can further include the fourth resistor R10 for current limiting, and the specific connection structure is shown in the above description and the accompanying drawings. Figure 2 The resistance value of the fourth resistor R10 can be 330 kΩ.

[0073] As a preferred embodiment, the low-voltage conduction module 2 further includes:

[0074] A third diode D1B, the cathode of which is connected with the emitter of the second PNP-type triode Q5, and the anode of which is used as the first end of the low-voltage conduction module 2, for current anti-reversal.

[0075] In the embodiment, the low-voltage conduction module 2 can further include the third diode D1B for current anti-reversal, and the specific connection structure is shown in the above description and the accompanying drawings. ​ The conduction voltage drop of the third diode D1B is 0.7 V, and the conduction voltage drop of the low-voltage conduction module 2 is updated to 1.4 V at this time.

[0076] The application further provides an electric tool controller, which includes a main switch, a to-be-powered module, a second capacitor, and the trigger starting circuit as described above.

[0077] For the electric tool controller provided in the application, please refer to the embodiments of the trigger starting circuit described above, and no longer be described here.

[0078] The various embodiments described in this specification are intended to be exemplary only. The subject matter described in this specification can be implemented in software, hardware, or a combination thereof. The various embodiments described in this specification can be implemented as part of a method, device, system, or apparatus, for example. The various embodiments described in this specification can be implemented as one or more computer programs that run on one or more computers or computer systems.

[0079] It should also be noted that, in this specification, terms such as first and second, etc., are used merely to distinguish one entity or action from another, and do not necessarily require or imply any actual such relationship or order between such entities or actions. Moreover, the terms "including," "including," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the statement "comprising a" does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0080] The above description of disclosed embodiments provides enabling teaching for a person skilled in the art to implement or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A trigger-start circuit, characterized in that, It includes a first controllable switch module, a low-voltage conduction module, a switch module, a first capacitor and a discharge module; The positive output terminal of the power supply is connected to the first terminal of the first controllable switch module and the first terminal of the main switch. The second terminal of the main switch is connected to one terminal of the second capacitor, the first terminal of the low-voltage conduction module, one terminal of the energy dissipation module, and the second terminal of the switch module. The other terminal of the second capacitor is grounded. One terminal of the first capacitor is connected to the other terminal of the energy dissipation module and the connection terminal is grounded. The first end of the switch module is connected to the control end of the low-voltage conduction module and the other end of the first capacitor, respectively, so as to conduct between its first end and the second end when the main switch is open, and to turn off between its first end and the second end when the main switch is closed. The second terminal of the first controllable switch module is connected to the power supply terminal of the module to be powered, and the control terminal is connected to the second terminal of the low-voltage conduction module, which is used to conduct when the main switch is closed and the low-voltage conduction module is turned on; the module to be powered is the main chip, the main chip is used to control the motor, and the second capacitor is used to absorb the reverse current of the motor; The low-voltage conduction module is used to conduct when the voltage difference between its first terminal and the control terminal is not less than its own conduction voltage drop; and to turn off when the voltage difference is less than the conduction voltage drop.

2. The trigger start circuit as described in claim 1, characterized in that, Also includes: The self-locking module has its input end connected to the first output end of the module to be powered, and its output end connected to the control end of the first controllable switch module. The power supply module is used to send a control signal to the control terminal of the first controllable switch module when the first controllable switch module is turned on, so as to keep the first controllable switch module turned on.

3. The trigger start circuit as described in claim 2, characterized in that, The self-locking module includes: The second resistor has one end serving as the output terminal of the self-locking module. The first diode has its cathode connected to the other end of the second resistor, and its anode serves as the input terminal of the self-locking module for current reverse protection.

4. The trigger start circuit as described in claim 1, characterized in that, The switching module includes a second diode, the anode of which serves as the first terminal of the switching module, and the cathode of which serves as the second terminal of the switching module.

5. The trigger start circuit as described in claim 1, characterized in that, The first controllable switch module includes: The first NPN transistor has its base serving as the control terminal of the first controllable switch module, and its emitter grounded. The base of the first PNP transistor is connected to the collector of the first NPN transistor, the emitter serves as the first terminal of the first controllable switch module, and the collector serves as the second terminal of the first controllable switch module.

6. The trigger start circuit as described in claim 5, characterized in that, It also includes a third resistor; The third resistor is disposed between the second terminal of the low-voltage conduction module and the control terminal of the first controllable switch module, with one end of the third resistor connected to the second terminal of the low-voltage conduction module and the other end of the third resistor connected to the control terminal of the first controllable switch module.

7. The trigger start circuit as described in any one of claims 1 to 6, characterized in that, The low-voltage conduction module includes: The second PNP transistor has its base as the control terminal of the low-voltage conduction module, its emitter as the first terminal of the low-voltage conduction module, and its collector as the second terminal of the low-voltage conduction module.

8. The trigger start circuit as described in claim 7, characterized in that, The low-voltage conduction module also includes: The fourth resistor has one end connected to the base of the second PNP transistor, and the other end serves as the second terminal of the low-voltage conduction module.

9. The trigger start circuit as described in claim 7, characterized in that, The low-voltage conduction module also includes: The third diode has its cathode connected to the emitter of the second PNP transistor, and its anode serves as the first terminal of the low-voltage conduction module for reverse current protection.

10. A power tool controller, characterized in that, It includes a main switch, a module to be powered, and a second capacitor, and also includes a trigger start circuit as described in any one of claims 1 to 9.

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