Electric tool

Abstract

The utility model discloses an electric tool which comprises a shell. The electric tool includes a housing, a motor, a power source, and a motion sensor configured to sense a motion of the housing; the motor parameter sensor is configured to sense working parameters of the motor; and the controller is respectively connected with the motor, the motion sensor and the motor parameter sensor, and the controller is configured to receive a motion signal of the motion sensor and a working signal of the motor parameter sensor so as to output the signals to the motor. The motion sensor and the motor parameter sensor are arranged, the controller detects the motion state of the tool and the working state of the motor at the same time, when the motion state of the tool is abnormal or the state of the motor is abnormal, the motor is controlled to stop in time, and safety is improved.

Description

[Technical field]

[0001] The utility model relates to the field of electric tools, in particular to an electric tool with high safety. [Background Technology]

[0002] With the widespread use of power tools, the operational safety of power tools has attracted more and more attention. Angle grinders, circular saws, hammer drills, etc. are commonly used power tools, which are generally driven by motors and can greatly improve work efficiency. When power tools are used abnormally, such as recoil, fall, or a large impact when the work is completed, it will cause harm to the user. Therefore, existing power tools are generally equipped with sensors, which transmit the signal of the power tool to the controller, so that the controller can determine whether to control the motor to stop. However, existing power tools generally use simple sensors, that is, a sensor can only detect the angular velocity or linear velocity of the power tool in a certain direction, etc., and does not have the function of simultaneously detecting whether the power tool is offset in multiple directions. If multiple sensors are set, the cost and volume will increase.

[0003] Please refer to Chinese utility model patent No. CN220051718U published on November 21, 2023, which discloses an electric tool, the electric tool includes a sensor, the sensor is a gyroscope sensor, and the motion acceleration signal includes an angular acceleration signal and / or a linear acceleration signal; because when the impact direction of the electric hammer or electric pick is perpendicular to or almost perpendicular to the surface of the desired impact object, the interior of the desired impact object suddenly breaks and splits, and the depth is deep, and the linear acceleration of the electric hammer or electric pick at this time is greater than the linear acceleration value of the electric hammer or electric pick under normal working conditions, therefore, the controller can comprehensively judge whether to disconnect the circuit between the power supply and the motor based on the angular acceleration signal and the linear acceleration signal. By setting the gyroscope sensor to sense the angular acceleration signal and the linear acceleration signal, it is possible to sense that the electric tool has a large change in the impact direction and control the shutdown in time, but it is not possible to control the shutdown in time when the electric tool recoils or falls.

[0004] In view of this, it is necessary to provide an improved electric tool to overcome the defects of the prior art. [Contents of the utility model]

[0005] In view of the deficiencies in the prior art, the purpose of the present utility model is to provide an electric tool which can promptly control the motor to stop when an abnormality occurs in the tool motion state or the motor state.

[0006] The technical solution adopted by the utility model to solve the problems of the prior art is: an electric tool, comprising: a shell; a motor, the motor is arranged in the shell; a power supply, connected to the motor to provide working current for the motor; the electric tool also includes: a motion sensor, the motion sensor is configured to sense the movement of the shell; a motor parameter sensor, the motor parameter sensor is configured to sense the working parameters of the motor; a controller, the controller is respectively connected to the motor, the motion sensor and the motor parameter sensor, the controller is configured to receive the motion signal of the motion sensor and the working signal of the motor parameter sensor, so as to output a signal to the motor.

[0007] A further improved solution is: the motion sensor is configured to detect the motion acceleration of the shell, and the motor parameter sensor is configured to detect the operating current of the motor.

[0008] A further improved solution is: the controller includes a timing unit, and the timing unit is configured to interrupt timing every 5 ms.

[0009] A further improvement is that the controller is configured to receive the motion acceleration An and the operating current In every 5 ms.

[0010] A further improvement is that the controller stores a motion acceleration threshold ΔA and an operating current threshold ΔI.

[0011] A further improvement is that the controller is also configured to output a signal to the motor to shut down the motor when the change in the motion acceleration An exceeds the motion acceleration threshold ΔA within a predetermined time period, and the change in the working current In exceeds the working current threshold ΔI within the predetermined time period.

[0012] A further improvement is that the motion sensor is a six-axis sensor, and the six-axis sensor detects the acceleration of the power tool in three directions of x, y, and z.

[0013] A further improvement is as follows: the six-axis sensor detects the displacement acceleration of the electric tool in the x-axis direction, and if a sudden change in the displacement acceleration is detected, the controller controls the motor to stop.

[0014] A further improvement is as follows: the six-axis sensor detects the rotational angular velocity of the electric tool in the y-axis direction, and if a sudden change in the rotational angular velocity is detected, the controller controls the motor to stop.

[0015] A further improvement is as follows: the six-axis sensor detects the gravity acceleration of the electric tool in the z-axis direction, and if a sudden change in the gravity acceleration is detected, the controller controls the motor to stop.

[0016] Compared with the prior art, the utility model has the following beneficial effects: the movement of the shell is sensed by the motion sensor, the working parameters of the motor are sensed by the motor parameter sensor, the controller receives the motion signal of the motion sensor and the working signal of the motor parameter sensor, and controls the on and off between the motor and the power supply based on the two signals, the controller simultaneously detects the motion state of the tool and the working state of the motor, and when the motion state of the tool is abnormal or the motor state is abnormal, the motor is promptly controlled to stop, thereby improving safety. [Drawings]

[0017] The specific implementation of the utility model is further described in detail below in conjunction with the accompanying drawings:

[0018] Figure 1 This is a sectional view of the entire electric tool of the utility model;

[0019] Figure 2 It is a control circuit diagram of the utility model electric tool;

[0020] Figure 3 It is a control flow chart of the electric tool of the utility model.

[0021] Meaning of the reference numerals in the figures:

[0022] Power tool 100 Housing 1

[0023] Head shell 2 Shield assembly 3

[0024] Saw blade 4 Handle 5

[0025] Foot plate 6 Switch 7

[0026] Motor 8 Power supply 9

[0027] Controller 10 Motion sensor 11

[0028] Motor parameter sensor 12 [Specific implementation method]

[0029] The utility model is further described in detail below in conjunction with the accompanying drawings and implementation modes.

[0030] The terms used in the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. For example, the words "upper", "lower", "front", "back", etc., which indicate the orientation or position relationship, are only based on the orientation or position relationship shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device / element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0031] See also Figure 1 and Figure 2 The figure shows a cross-sectional view and a control circuit diagram of the electric tool of the utility model, and the electric tool 100 is preferably an angle grinder. The angle grinder 100 includes a housing 1, a motor 8 disposed in the housing 1, a power supply 9 connected to the motor 8, a head housing 2 installed in front of the housing 1, a support seat (not shown) fixed below the head housing 2, a shield assembly 3 connected to the support seat, a transmission assembly driven by the motor 8 (not shown), and a saw blade 4 detachably connected to the transmission assembly and disposed below the support seat, the head housing 2 and the support seat enclose a receiving cavity, the receiving cavity accommodates the transmission assembly, and when the angle grinder 100 is working, the power supply 9 provides working current to the motor 8, the motor 8 drives the transmission assembly, and the transmission assembly drives the saw blade 4 to perform cutting or grinding operations.

[0032] The housing 1 further includes a handle portion 5 and a foot portion 6. The handle portion 5 is mounted at the rear of the head shell 2. The foot portion 6 is mounted at the rear of the handle portion 5. The foot portion 6 is configured to install a battery pack. A controller 10 is installed at the connection between the handle portion 5 and the foot portion 6. The controller 10 includes a timing unit therein. The timing unit is configured to detect the operation time of the controller 10. The angle grinder 100 further includes a switch 7. The switch 7 is configured to provide a trigger signal to the controller 10. When the battery pack is installed to the angle grinder 100, the battery pack supplies power to the power supply 9. When the switch 7 is pressed, the switch 7 sends a trigger signal to the controller 10. The controller 10 controls the operation of the motor 8.

[0033] The controller 10 is also connected to a motor parameter sensor 12, which is configured to sense the working parameters of the motor 8. The handle portion 5 is provided with a motion sensor 11, which is configured to sense the movement of the housing 1, and the controller 10 is configured to receive a motion signal from the motion sensor 11 and a working signal from the motor parameter sensor 12, and control the on / off of the path between the motor 8 and the power source 9 based on the motion signal and the working signal.

[0034] The motion sensor 11 is configured to detect the motion acceleration of the housing 1, and the motor parameter sensor 12 is configured to detect the working current of the motor 8. In this embodiment, the motion sensor 11 is preferably a six-axis sensor, and the six-axis sensor 11 detects the acceleration of the power tool 100 in the three directions of x, y, and z. The output direction of the motor 8 is defined as the x-axis direction, the direction perpendicular to the x-axis is defined as the y-axis direction, and the direction perpendicular to the plane where the x-axis and y-axis are located is defined as the z-axis direction.

[0035] The controller 10 is configured to receive the motion acceleration detected by the motion sensor 11 in time periods, recorded as A0, A1, A2...An; the controller 10 is also configured to receive the working current detected by the motor parameter sensor 12 in time periods, recorded as I0, I1, I2...In. In this embodiment, the controller 10 records the initial motion acceleration and the initial working current as A0 and I0 respectively; the controller 10 continues to run, the timing unit is interrupted after 5ms, and the controller 10 records the motion acceleration and the working current as A1 and I0 respectively; repeat the above operations, and the controller 10 records the motion acceleration and the working current as An and In respectively.

[0036] When the angle grinder 100 is working normally, it outputs along the x-axis direction to work, and the six-axis sensor 11 detects the displacement acceleration Axn of the angle grinder 100 in the x-axis direction. If a sudden change in the displacement acceleration Axn is detected, it indicates that the angle grinder 100 has completed the work at this time, and the controller 10 controls the motor 8 to stop. When the angle grinder 100 deviates in the y-axis direction, the six-axis sensor 11 detects the rotation angular velocity Ayn of the angle grinder 100 in the y-axis direction. If a sudden change in the rotation angular velocity Ayn is detected, it indicates that the angle grinder 100 has completed the work at this time, and the controller 10 controls the motor 8 to stop. A sudden change indicates that the body of the angle grinder 100 has rotated and deviated from the normal working direction, which may easily cause damage to the user's hands. The controller 10 controls the motor 8 to stop in time. When the angle grinder 100 deviates in the z-axis direction, the six-axis sensor 11 detects the gravitational acceleration Azn of the angle grinder 100 in the z-axis direction. If a sudden change in the gravitational acceleration Azn is detected, it indicates that the body of the angle grinder 100 has recoiled or fallen, which may easily cause damage to the user. The controller 10 controls the motor 8 to stop in time.

[0037] See also Figure 3As shown, it is a control flow chart of the electric tool of the utility model. When the battery pack is installed on the foot plate 6, the battery pack supplies power to the power supply 9, the controller 10 is powered, the switch 7 is pressed, the controller 10 detects the closing signal of the switch 7 and controls the motor 8 to run, the timing unit starts to work, the controller 10 reads the initial motion acceleration Ax0, Ay0, Az0 detected by the six-axis sensor 11 and the initial working current I0 detected by the motor parameter sensor 12, and stores them inside the controller 10. After the motor 8 runs for 5ms, the timing unit is interrupted, and the controller 10 reads the current The motion accelerations Ax1, Ay1, Az1 detected by the six-axis sensor 11 and the working current I1 detected by the motor parameter sensor are respectively calculated, and the differences ΔAx1, ΔAy1, ΔAz1 between the motion accelerations Ax0, Ax1, Ay0, Ay1, Az0, Az1 and the difference ΔI1 between the working currents I0 and I1 are respectively calculated. The controller 10 also stores a motion acceleration threshold ΔA and a working current threshold ΔI. When any difference among the differences ΔAx1, ΔAy1, ΔAz1 is greater than the motion acceleration threshold ΔA and the difference ΔI1 is greater than the working current threshold ΔI, it indicates that at this time the When the acceleration of the angle grinder 100 in any direction of the x, y, and z axes suddenly changes or the motor is blocked or otherwise abnormal, the controller 10 controls to disconnect the path between the motor 8 and the power supply 9, and the motor 8 stops; when any difference among the differences ΔAx1, ΔAy1, and ΔAz1 does not satisfy the condition of being greater than the threshold ΔA or the difference ΔI1 does not satisfy the condition of being greater than the threshold ΔI, the timing unit continues to time for 5ms, and the controller 10 continues to receive the motion accelerations Ax2, Ay2, Az2 and the working current I2, and calculates the motion accelerations Ax1, Ax2, Ay1, Ay2, A The differences ΔAx2, ΔAy2, ΔAz2 between z1 and Az2 and the difference ΔI2 between the working currents I1 and I2, when any of the differences ΔAx2, ΔAy2, ΔAz2 is greater than the motion acceleration threshold ΔA and the difference ΔI2 is greater than the working current threshold ΔI, the controller 10 controls the motor 8 to shut down; if at least one of the differences ΔAx2, ΔAy2, ΔAz2, ΔI1 does not meet the condition for shutting down the motor 8, continue to calculate and judge the relationship between the differences ΔAxn, ΔAyn, ΔAzn, ΔIn and the thresholds ΔA, ΔI until the condition for shutting down the motor 8 is met.

[0038] In the utility model, the movement of the shell is sensed by the motion sensor, the working parameters of the motor are sensed by the motor parameter sensor, the controller receives the motion signal of the motion sensor and the working signal of the motor parameter sensor, and controls the on-off connection between the motor and the power supply based on the two signals. The controller simultaneously detects the motion state of the tool and the working state of the motor. When the motion state of the tool is abnormal or the motor state is abnormal, the motor is promptly controlled to stop to improve safety.

[0039] The utility model is not limited to the above specific implementations. Those skilled in the art can easily understand that there are many other alternatives to the power tool of the utility model without departing from the principle and scope of the utility model. The protection scope of the utility model shall be based on the content of the claims.

Claims

1. An electric tool, comprising: case; A motor, wherein the motor is disposed in the housing; A power supply is connected to the motor to provide a working current for the motor; it is characterized in that: the power tool also includes: a motion sensor, which is configured to sense the movement of the shell; a motor parameter sensor, which is configured to sense the working parameters of the motor; a controller, which is respectively connected to the motor, the motion sensor and the motor parameter sensor, and the controller is configured to receive the motion signal of the motion sensor and the working signal of the motor parameter sensor so as to output a signal to the motor.

2. The electric tool according to claim 1, characterized in that: The motion sensor is configured to detect the motion acceleration of the housing, and the motor parameter sensor is configured to detect the operating current of the motor.

3. The electric tool according to claim 2, characterized in that: The controller includes a timing unit configured to interrupt timing at intervals of 5 ms.

4. The electric tool according to claim 3, characterized in that: The controller is configured to receive the motion acceleration An and the operating current In every 5 ms.

5. The electric tool according to claim 4, characterized in that: The controller stores a motion acceleration threshold ΔA and an operating current threshold ΔI.

6. The electric tool according to claim 5, characterized in that: The controller is also configured to output a signal to the motor to shut down the motor when the change in the motion acceleration An exceeds the motion acceleration threshold ΔA within a predetermined time period and the change in the operating current In exceeds the operating current threshold ΔI within the predetermined time period.

7. The electric tool according to claim 2, characterized in that: The motion sensor is a six-axis sensor, and the six-axis sensor detects the acceleration of the electric tool in three directions of x, y, and z axes.

8. The electric tool according to claim 7, characterized in that: The six-axis sensor detects the displacement acceleration of the electric tool in the x-axis direction. If a sudden change in the displacement acceleration is detected, the controller controls the motor to stop.

9. The electric tool according to claim 8, characterized in that: The six-axis sensor detects the rotational angular velocity of the electric tool in the y-axis direction. If a sudden change in the rotational angular velocity is detected, the controller controls the motor to stop.

10. The electric tool according to claim 9, characterized in that: The six-axis sensor detects the gravity acceleration of the electric tool in the z-axis direction. If a sudden change in the gravity acceleration is detected, the controller controls the motor to stop.

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