Trigger galloping early warning circuit and early warning method thereof

Abstract

The invention discloses a trigger galloping early-warning circuit and an early-warning method thereof, and relates to the technical field of electric tools, the trigger galloping early-warning circuit comprises a trigger follow-up resistor which adjusts the magnitude of an access voltage according to the pressing degree of a trigger, the trigger is directly grounded when the trigger is completely loosened, and the trigger is directly accessed to a working voltage when the trigger is completely pressed down; the signal acquisition module outputs a corresponding voltage fluctuation signal to the main control chip according to the real-time position of the trigger during the switching-on period of the working voltage; and the main control chip judges whether the trigger is in a complete loosening state or not when the working voltage is switched on according to the voltage fluctuation signal, and sends a trigger galloping early warning signal when judging that the trigger is not in the complete loosening state. The voltage rising trend is resisted by utilizing the characteristics of the capacitor, so that the voltage fluctuation signal with the fluctuation characteristic under the normal condition is generated, the voltage fluctuation signal is in the linear rising trend under the abnormal state, the galloping risk is judged in time, and an early warning behavior is made.

Description

Technical Field

[0001] The present invention relates to the technical field of electric tools, and in particular to a trigger runaway warning circuit and a warning method thereof. Background Art

[0002] During the use of electric tools, if the product fails to be powered off in time, it is very easy to cause a runaway accident due to short-term high output after powering on again, which in turn causes unpredictable personal injury. In order to prevent the threat to the user's personal safety caused by the instantaneous power-on of electric products, a runaway warning circuit is urgently needed to detect the working conditions of the electric product when it is started, so as to achieve the purpose of protecting the user's safety. Summary of the invention

[0003] In order to solve the danger of electric tools running away when powered on instantly, the present invention proposes a trigger running away warning circuit, comprising:

[0004] The trigger follower resistor is used to adjust the input voltage according to the degree of trigger pressing. When the trigger is fully released, the trigger is directly connected to the ground. When the trigger is fully pressed, the trigger is directly connected to the working voltage.

[0005] The signal acquisition module outputs the corresponding voltage fluctuation signal to the main control chip according to the real-time position of the trigger during the period when the working voltage is connected;

[0006] The main control chip determines whether the trigger is in a fully released state when the working voltage is turned on according to the voltage fluctuation signal, and sends a trigger runaway warning signal when it is determined that the trigger is not in a fully released state.

[0007] Furthermore, in the signal acquisition module, when the trigger is fully released and connected to the working voltage, and the trigger enters the fully pressed state from the fully released state, the voltage fluctuation signal shows a fluctuating upward trend; when the trigger is not fully released and connected to the working voltage, the voltage fluctuation signal shows a linear upward trend while the working voltage is connected.

[0008] Furthermore, in the trigger follower resistor, one end of the resistor is grounded, the other end of the resistor is connected to the working voltage, and the slider outputs the adjusted voltage.

[0009] Furthermore, the signal acquisition module includes a twelfth capacitor and a twenty-third resistor in parallel, one end of the parallel connection is grounded, the other end of the parallel connection outputs a voltage fluctuation signal, and the adjusted voltage is connected through the thirteenth resistor.

[0010] Furthermore, when the trigger is fully released and connected to the working voltage, during the period when the trigger changes from a fully released state to a fully pressed state, the fluctuation rising trend of the voltage fluctuation signal is controlled based on the characteristics of the twelfth capacitor.

[0011] The present invention also proposes a trigger runaway warning method, comprising the steps of:

[0012] S1: When the working voltage is on, the voltage is adjusted based on the real-time position of the trigger follower resistor;

[0013] S2: Through the signal acquisition module, the corresponding voltage fluctuation signal is output to the main control chip according to the change of the input voltage;

[0014] S3: The main control chip determines whether the trigger is in a completely released state when the working voltage is turned on based on the voltage fluctuation signal, and sends a trigger runaway warning signal when it is determined that the trigger is not in a completely released state.

[0015] Furthermore, in the step S3, the determination basis is:

[0016] When the trigger is fully released and the working voltage is connected, the voltage fluctuation signal shows a fluctuating upward trend during the period when the trigger changes from the fully released state to the fully pressed state. When the trigger is not fully released and the working voltage is connected, the voltage fluctuation signal shows a straight upward trend while the working voltage is connected.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects:

[0018] The trigger runaway warning circuit and the warning method thereof described in the present invention use sliding resistors and capacitors to change the voltage of the access circuit as the trigger is pressed, and use the characteristics of the capacitor itself to resist the rising trend of the voltage, thereby generating a voltage fluctuation signal with a fluctuation characteristic under normal circumstances, while under abnormal conditions, the voltage fluctuation signal presents a straight rising trend, thereby timely judging the runaway risk, taking warning actions, and avoiding the personal injury that may be caused by the runaway. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention is a circuit diagram of a trigger runaway warning circuit;

[0020] Figure 2 A step diagram of a trigger runaway warning method;

[0021] Figure 3 This is a schematic diagram of the voltage fluctuation signal changes under normal conditions;

[0022] Figure 4 Schematic diagram of voltage fluctuation signal changes under abnormal conditions. DETAILED DESCRIPTION

[0023] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0024] Embodiment 1

[0025] like Figure 1 As shown, in order to avoid the problem of overrunning of the electric tool during abnormal power-off and power-on, the present invention proposes a trigger overrunning warning circuit, comprising:

[0026] The trigger follower resistor is used to adjust the input voltage according to the degree of trigger pressing. When the trigger is fully released, the trigger is directly connected to the ground. When the trigger is fully pressed, the trigger is directly connected to the working voltage.

[0027] The signal acquisition module outputs the corresponding voltage fluctuation signal to the main control chip according to the real-time position of the trigger during the period when the working voltage is connected;

[0028] The main control chip determines whether the trigger is in a fully released state when the working voltage is turned on according to the voltage fluctuation signal, and sends a trigger runaway warning signal when it is determined that the trigger is not in a fully released state.

[0029] Among them, the trigger follower resistor is essentially a sliding resistor R12 whose slider moves with the trigger pressing. When the trigger is fully released, the slider is at the leftmost end (in the figure), and the leftmost end of the sliding resistor R12 is connected to the fourth pin KL_2 of the first connector J1, and the fourth pin KL_2 is grounded through the seventh pin connected to the inside of the first connector J1; when the trigger is fully pressed, the slider is at the rightmost end (in the figure), and the rightmost end of the sliding resistor R12 is connected to the fifth pin KL_1 of the first connector J1, and the fifth pin KL_1 is connected to the working voltage (+5V) through the eighth pin connected to the inside of the first connector J1.

[0030] The signal acquisition module includes a twelfth capacitor C12 and a twenty-third resistor R23 connected in parallel, one end of the parallel connection is grounded, the other end of the parallel connection outputs a voltage fluctuation signal SPEED, and the adjusted voltage is connected through the thirteenth resistor R13.

[0031] like Figure 3 As shown (yellow is the voltage fluctuation signal, purple is the power-on voltage signal), it is not difficult to see from the circuit designed according to the present invention that when the trigger is fully released, since the slider of the sliding resistor R12 is equivalent to grounding, the voltage fluctuation signal at this time remains at 0V, and during the trigger pressing process, the voltage connected to the circuit gradually increases to +5V, so the voltage fluctuation signal will also increase to 5V. However, due to the influence of the twelfth capacitor C12, it will suppress the voltage fluctuation (here it is to resist the increase of voltage), so before the slider is fully pressed, the entire voltage fluctuation signal is in a state of fluctuation and rise, and after pressing to the bottom, since the input voltage has reached the maximum value of 5V, no fluctuation occurs, so the voltage fluctuation signal is in a stable state.

[0032] If the power tool is powered off abnormally and the trigger is not fully released, if the power is suddenly restored, the power supply voltage can still be input into the circuit through the sliding resistor R12 because the trigger is not fully released. Figure 4 As shown in the figure, when the power supply is restored, the trigger does not slide. At this time, the twelfth capacitor C12 will reach full capacity in an instant (milliseconds). Therefore, the voltage fluctuation signal will rise instantly from the 0V state before the power supply is restored, and remain in a high and stable state. The sudden restoration of power supply without warning can easily cause the power tool to run away.

[0033] Based on the above principle, we can determine whether there is a risk of runaway according to the characteristics of the voltage signal fluctuations, and notify the main control chip to execute the corresponding runaway protection mechanism.

[0034] In order to better understand the technical content of the present invention, this embodiment also describes the present invention in the form of method steps, such as Figure 2 As shown, a trigger runaway warning method comprises the steps of:

[0035] S1: When the working voltage is on, the voltage is adjusted based on the real-time position of the trigger follower resistor;

[0036] S2: Through the signal acquisition module, the corresponding voltage fluctuation signal is output to the main control chip according to the change of the input voltage;

[0037] S3: The main control chip determines whether the trigger is in a completely released state when the working voltage is turned on based on the voltage fluctuation signal, and sends a trigger runaway warning signal when it is determined that the trigger is not in a completely released state.

[0038] Furthermore, in step S3, the determination basis is:

[0039] When the trigger is fully released and the working voltage is connected, the voltage fluctuation signal shows a fluctuating upward trend during the period when the trigger changes from the fully released state to the fully pressed state. When the trigger is not fully released and the working voltage is connected, the voltage fluctuation signal shows a straight upward trend while the working voltage is connected.

[0040] In summary, the trigger runaway warning circuit and its warning method described in the present invention, through the use of sliding resistors and capacitors, changes the voltage of the access circuit as the trigger is pressed, and utilizes the characteristics of the capacitor itself to resist the rising trend of the voltage, thereby generating a voltage fluctuation signal with a fluctuation characteristic under normal circumstances, while under abnormal conditions, the voltage fluctuation signal presents a straight upward trend, thereby timely judging the runaway risk, taking warning actions, and avoiding the personal injury that may be caused by the runaway.

[0041] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0042] In addition, in the present invention, descriptions such as "first", "second", "one", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0043] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. A trigger runaway warning circuit, It is characterized in that include: The trigger follower resistor is used to adjust the input voltage according to the degree of trigger pressing. When the trigger is fully released, the trigger is directly connected to the ground. When the trigger is fully pressed, the trigger is directly connected to the working voltage. The signal acquisition module outputs the corresponding voltage fluctuation signal to the main control chip according to the real-time position of the trigger during the period when the working voltage is connected; The main control chip determines whether the trigger is in a fully released state when the working voltage is turned on according to the voltage fluctuation signal, and sends a trigger runaway warning signal when it is determined that the trigger is not in a fully released state.

2. A trigger runaway warning circuit as claimed in claim 1, It is characterized in that The signal acquisition module, when the trigger is fully released and connected to the working voltage, the voltage fluctuation signal shows a fluctuating upward trend during the period when the trigger changes from a fully released state to a fully pressed state. When the trigger is not fully released and connected to the working voltage, the voltage fluctuation signal shows a linear upward trend while the working voltage is connected.

3. A trigger runaway warning circuit as claimed in claim 2, It is characterized in that In the trigger follower resistor, one end of the resistor is grounded, the other end of the resistor is connected to the working voltage, and the slider outputs the adjusted voltage.

4. A trigger runaway warning circuit as claimed in claim 3, It is characterized in that The signal acquisition module includes a twelfth capacitor and a twenty-third resistor connected in parallel, one end of the parallel connection is grounded, the other end of the parallel connection outputs a voltage fluctuation signal, and the adjusted voltage is connected through the thirteenth resistor.

5. A trigger runaway warning circuit as claimed in claim 4, It is characterized in that When the trigger is fully released and connected to the working voltage, during the period when the trigger changes from a fully released state to a fully pressed state, the fluctuation rising trend of the voltage fluctuation signal is controlled based on the characteristics of the twelfth capacitor.

6. A warning method applied to the trigger runaway warning circuit according to any one of claims 1 to 5, It is characterized in that Includes steps: S1: When the working voltage is on, the voltage is adjusted based on the real-time position of the trigger follower resistor; S2: Through the signal acquisition module, the corresponding voltage fluctuation signal is output to the main control chip according to the change of the input voltage; S3: The main control chip determines whether the trigger is in a completely released state when the working voltage is turned on based on the voltage fluctuation signal, and sends a trigger runaway warning signal when it is determined that the trigger is not in a completely released state.

7. The early warning method according to claim 6, It is characterized in that In the step S3, the determination is based on: When the trigger is fully released and the working voltage is connected, the voltage fluctuation signal shows a fluctuating upward trend during the period when the trigger changes from the fully released state to the fully pressed state. When the trigger is not fully released and the working voltage is connected, the voltage fluctuation signal shows a straight upward trend while the working voltage is connected.

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