Angle grinder control method, angle grinder, electric tool control method, and electric tool

Abstract

An angle grinder control method, an angle grinder, an electric tool control method, and an electric tool. The angle grinder control method comprises: controlling a motor to start (S110); acquiring an initial value of an orientation change amount detected by an orientation sensing device (S120); adjusting a threshold of the orientation change amount on the basis of the initial value of the orientation change amount (S130); acquiring a first parameter value of the motor and a real-time value of the orientation change amount of the angle grinder (S140); and when the first parameter value exceeds a threshold range and the real-time value of the orientation change amount is higher than the adjusted threshold of the orientation change amount, controlling the motor to shut down (S150).

Description

Angle grinder control methods, angle grinder, power tool control methods and power tools

[0001] This application claims priority to Chinese Patent Application No. 202410687820.6, filed with the Chinese Patent Office on May 30, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to power tool control methods and the field of power tool technology, such as angle grinder control methods, angle grinders, power tool control methods, and power tools. Background Technology

[0003] With the development of electric technology, cutting tools have emerged. Cutting tools mainly include angle grinders and cutting machines. Most cutting tools use motors to drive tool accessories, namely cutting discs or grinding discs, to cut or grind objects.

[0004] In related technologies, in order to sense the change in the posture of a cutting tool, a gyroscope is often installed in the shell of the cutting tool to detect the rate of change of the cutting tool's speed in space. When the rate of change of the cutting tool's speed is detected to exceed a predetermined threshold, certain controls are made on the cutting tool, such as stopping it, so that the cutting tool can be processed based on the sensed change in its posture.

[0005] However, current cutting tools equipped with gyroscopes are subject to limitations imposed by tool accessories during use, which can easily lead to deviations in the detected rate of change of speed, resulting in miscontrol.

[0006] Summary of the Invention

[0007] To address the problem of miscontrol of cutting tools, this paper provides a control method for an angle grinder, an angle grinder, a control method for power tools, and a power tool.

[0008] In a first aspect, this application provides an angle grinder control method for an angle grinder, the angle grinder including a motor, a control device, and a posture sensing device, the control device being configured to control the rotation of the motor, and the angle grinder control method being executed by the control device; the angle grinder control method includes:

[0009] Control the motor to start;

[0010] Obtain the initial value of the attitude change of the angle grinder detected by the attitude sensing device;

[0011] The threshold value of the attitude change of the angle grinder is adjusted based on the initial value of the attitude change.

[0012] Obtain the first parameter value of the electric motor and the real-time value of the attitude change of the angle grinder;

[0013] In response to the first parameter value exceeding the threshold range and the real-time value of the attitude change being higher than the adjusted attitude change threshold, the motor is controlled to stop.

[0014] In some embodiments, the attitude change includes a first-direction attitude change, a second-direction attitude change perpendicular to the first-direction attitude change, and a third-direction attitude change perpendicular to the first-direction attitude change and the second-direction attitude change, respectively.

[0015] The step of controlling the motor to stop in response to the first parameter value exceeding the threshold range and the real-time value of the attitude change being higher than the adjusted attitude change threshold includes:

[0016] In response to the first parameter value exceeding the threshold range and satisfying at least one of the following conditions: the real-time value of the first directional attitude change is higher than the adjusted threshold value of the first directional attitude change, the real-time value of the second directional attitude change is higher than the adjusted threshold value of the second directional attitude change, and the real-time value of the third directional attitude change is higher than the adjusted threshold value of the third directional attitude change, the motor is controlled to stop.

[0017] In some embodiments, obtaining the initial value of the attitude change of the angle grinder detected by the attitude sensing device includes:

[0018] The attitude change detected by the attitude sensing device within a predetermined time period is obtained;

[0019] The maximum value of the attitude change within the predetermined time period is used as the initial value of the attitude change.

[0020] In some implementations, obtaining the first parameter value of the motor includes:

[0021] Obtain the parameter sampling values ​​of the motor;

[0022] The first parameter value is obtained by delaying the sampled parameter values.

[0023] In some implementations, the step of delaying the sampled parameter values ​​to obtain the first parameter value includes:

[0024] Retrieve the historical first parameter value;

[0025] The current first parameter value is obtained by processing the sampled parameter value and the historical first parameter value.

[0026] In some implementations, obtaining the current first parameter value based on the parameter sample value and historical first parameter values ​​includes:

[0027] The current first parameter value is obtained based on the first value and the second value that is positively correlated with the first value;

[0028] Wherein, the first value is the parameter sampling value of the first set weight, and the second value is the historical first parameter value of the second set weight; the first set weight is less than the second set weight.

[0029] In some implementations, adjusting the threshold for the attitude change of the angle grinder based on the initial value of the attitude change includes:

[0030] The threshold value of the attitude change is obtained based on the initial value of the attitude change and the influencing factor.

[0031] Wherein, the influence factor is greater than 1; the first parameter value is the current value or the rotational speed value.

[0032] Secondly, this application provides an angle grinder, comprising:

[0033] shell;

[0034] The electric motor is housed within the housing;

[0035] The grinding disc is driven by the electric motor;

[0036] An attitude sensing device, at least partially housed within the housing, is configured to detect changes in the attitude of the housing.

[0037] The working detection device is configured to detect the working parameters of the motor and output a working signal;

[0038] The control device outputs a control signal in response to the processing result of the working signal and the attitude change amount;

[0039] A power supply device that, in response to the control signal, selectively provides electrical energy to the motor;

[0040] The control device is configured to perform the angle grinder control method described in any of the above embodiments.

[0041] In some embodiments, the control device includes a parameter processing module configured to perform a delay processing on the parameter sample values;

[0042] The parameter processing module is also configured to store historical values ​​of the first parameter and calculate the current value of the first parameter.

[0043] In some embodiments, the control device further includes an attitude change processing module, which is configured to adjust a threshold value of the attitude change based on an initial value of the attitude change.

[0044] Thirdly, this application provides a power tool control method for a power tool, the power tool including a motor, a control device, and a posture sensing device, the control device being configured to control the rotation of the motor, and the power tool control method being executed by the control device; the power tool control method includes:

[0045] Control the motor to start;

[0046] Obtain the initial value of the attitude change of the power tool detected by the attitude sensing device;

[0047] The threshold value of the attitude change of the power tool is adjusted based on the initial value of the attitude change.

[0048] Obtain the first parameter value of the electric motor and the real-time value of the attitude change of the power tool;

[0049] In response to the first parameter value exceeding the threshold range and the real-time value of the attitude change being higher than the adjusted attitude change threshold, the motor is controlled to stop.

[0050] In some embodiments, the attitude change includes a first-direction attitude change, a second-direction attitude change perpendicular to the first-direction attitude change, and a third-direction attitude change perpendicular to the first-direction attitude change and the second-direction attitude change, respectively.

[0051] The step of controlling the motor to stop in response to the first parameter value exceeding the threshold range and the real-time value of the attitude change being higher than the adjusted attitude change threshold includes:

[0052] In response to the first parameter value exceeding the threshold range and satisfying at least one of the following conditions: the real-time value of the first directional attitude change is higher than the adjusted threshold value of the first directional attitude change, the real-time value of the second directional attitude change is higher than the adjusted threshold value of the second directional attitude change, and the real-time value of the third directional attitude change is higher than the adjusted threshold value of the third directional attitude change, the motor is controlled to stop.

[0053] In some embodiments, obtaining the initial value of the attitude change of the power tool detected by the attitude sensing device includes:

[0054] The attitude change detected by the attitude sensing device within a predetermined time period is obtained;

[0055] The maximum value of the attitude change within the predetermined time period is used as the initial value of the attitude change.

[0056] In some implementations, obtaining the first parameter value of the motor includes:

[0057] Obtain the parameter sampling values ​​of the motor;

[0058] The first parameter value is obtained by delaying the sampled parameter values.

[0059] In some implementations, the step of delaying the sampled parameter values ​​to obtain the first parameter value includes:

[0060] Retrieve the historical first parameter value;

[0061] The current first parameter value is obtained by processing the sampled parameter value and the historical first parameter value.

[0062] In some implementations, obtaining the current first parameter value based on the parameter sample value and historical first parameter values ​​includes:

[0063] The current first parameter value is obtained based on the first value and the second value that is positively correlated with the first value;

[0064] Wherein, the first value is the parameter sampling value of the first set weight, and the second value is the historical first parameter value of the second set weight; the first set weight is less than the second set weight.

[0065] In some implementations, adjusting the threshold for the attitude change based on the initial value of the attitude change includes:

[0066] The threshold value of the attitude change is obtained based on the initial value of the attitude change and the influencing factor.

[0067] Wherein, the influence factor is greater than 1; the first parameter value is the current value or the rotational speed value.

[0068] Fourthly, this application provides an electric tool, comprising:

[0069] shell;

[0070] The electric motor is housed within the housing;

[0071] The tool accessory is driven by the electric motor;

[0072] An attitude sensing device, at least partially housed within the housing, is configured to detect changes in attitude of the tool accessory and the housing.

[0073] The working detection device is set to detect the working parameters of the motor and output a working signal;

[0074] The control device outputs a control signal in response to the processing results of the working signal and the attitude change.

[0075] A power supply device that, in response to the control signal, selectively provides electrical energy to the motor;

[0076] The control device is configured to perform the power tool control method described in any of the above embodiments.

[0077] In some embodiments, the control device includes a parameter processing module configured to perform a delay processing on the parameter sample values;

[0078] The parameter processing module is also configured to store historical values ​​of the first parameter and calculate the current value of the first parameter.

[0079] In some embodiments, the control device further includes an attitude change processing module, which is configured to adjust a threshold value of the attitude change based on an initial value of the attitude change. Attached Figure Description

[0080] Figure 1 is a flowchart of a power tool control method according to an embodiment of this application;

[0081] Figure 2 is a schematic diagram of the main body of a power tool according to an embodiment of this application;

[0082] Figure 3 is a schematic diagram of the control logic of a power tool in one embodiment of this application.

[0083] Figure descriptions: 201, outer casing; 202, electric motor; 203, tool accessories; 204, attitude sensing device; 205, work detection device; 206, control device; 207, power supply device; 208, parameter processing module; 209, attitude change processing module. Detailed Implementation

[0084] The specific embodiments of this application are described below with reference to the accompanying drawings. Many details are set forth in the following description to aid in understanding this application. However, this application can be implemented in other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application.

[0085] In the description of this application, the terms “center,” “longitudinal,” “lateral,” “length,” “width,” “thickness,” “upper,” “lower,” “front,” “rear,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” “outer,” “clockwise,” “counterclockwise,” “axial,” “radial,” and “circumferential” indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation.

[0086] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise expressly defined.

[0087] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the meaning of the above terms in this application as appropriate.

[0088] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature and the second feature are in direct contact, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or that the first feature is at a lower horizontal level than the second feature.

[0089] When an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementations.

[0090] Referring to Figure 1, Figure 1 shows a flowchart of a control method for a power tool according to an embodiment of this application. This control method is used to control a power tool, such as one with cutting and grinding functions, like an angle grinder and a cutting machine. A power tool generally includes a tool attachment, a motor, a control device, and a posture sensing device. The control device can be configured to control the motor to drive the tool attachment to rotate. The posture sensing device can be a three-axis motion sensor or a three-axis gyroscope, configured to detect the acceleration of the power tool in three-dimensional space. This control method can be based on the control device and can be executed by the control device as the executing entity. An embodiment of this application provides a control method for a power tool, including the following steps:

[0091] Step 110: Control the motor to start.

[0092] For example, the control device can start the motor after receiving a switch signal. The switch signal can be analog or digital, and can be output by the operator and acquired by the control device. After the motor starts, it enters the working state. It can be understood that the motor will generally enter an unloaded state first. After the power tool contacts the working surface, the motor will switch to a loaded state, at which point the motor's operating current or speed will change compared to the unloaded state.

[0093] Step 120: Obtain the initial value of the attitude change detected by the attitude sensing device.

[0094] For example, the control device can acquire the initial value of the attitude change detected by the attitude sensing device after the control motor is started. The initial value of the attitude change can be caused by the rotation of the tool attachment under the drive of the motor when the power tool is in an unloaded state. The tool attachment can be a disc-shaped attachment such as a grinding disc or cutting disc. Due to inaccurate centering, uneven mass, and different degrees of wear of the disc-shaped attachment, the initial value of the attitude change measured after the tool attachment is installed on the output shaft will be different.

[0095] Step 130: Adjust the threshold of attitude change based on the initial value of attitude change.

[0096] For example, after obtaining the initial value of the attitude change detected by the sensing device, the control device can process the initial value of the attitude change and adjust it to obtain the threshold of the attitude change, which is then used as the benchmark for subsequent judgment.

[0097] Step 140: Obtain the first parameter value of the motor and the real-time value of the attitude change of the power tool.

[0098] For example, the control device can adjust the threshold of the attitude change based on the initial value of the attitude change, and then obtain the first parameter value of the motor and the real-time value of the attitude change of the power tool. The first parameter value of the motor can be obtained by an additional detection device or by reading the parameters of the motor, and the real-time value of the attitude change of the power tool can be obtained by an attitude sensing device. Step 140 can be before step 130, before step 120, or even before step 110. Here, for the sake of resource conservation, step 140 is placed after step 130.

[0099] Step 150: When the value of the first parameter exceeds the threshold range and the real-time value of the attitude change is higher than the threshold of the adjusted attitude change, control the motor to stop.

[0100] For example, after acquiring the first parameter value of the motor and the real-time value of the attitude change of the power tool, the control device can make a judgment based on the first parameter value of the motor and the real-time value of the attitude change of the power tool. When the first parameter value exceeds the threshold range and the real-time value of the attitude change is higher than the adjusted threshold value of the attitude change, the control device can control the motor to stop. When the first parameter value exceeds the threshold range, it indicates that the motor is in a relatively unloaded state; for example, the tool attachment of the power tool may have detached from the working surface, or the operator may not have applied the tool attachment to the working surface, or the motor's power may not be transmitted to the tool attachment, i.e., the load of the tool attachment cannot be transmitted to the motor. When the real-time value of the attitude change is higher than the adjusted threshold value of the attitude change, it indicates that the power tool has suffered a severe impact, such as falling to the ground causing a sudden change in acceleration. Therefore, the control device controls the motor to stop to reduce the probability of danger. The first parameter can be a current value or a speed value. When the parameter value is a current value, the first parameter value exceeding the threshold range means that the first current value is lower than a predetermined value. When the parameter value is a speed value, the first parameter value exceeding the threshold range means that the first speed value is higher than a predetermined value.

[0101] To eliminate the influence of occasional factors on the rotational speed, when the parameter value is the rotational speed value, the control device will stop the motor when it detects that the first rotational speed value is higher than the predetermined value a predetermined number of times within a predetermined time and the real-time value of the attitude change is higher than the adjusted attitude change threshold. The predetermined time and predetermined number of times can be set based on empirical values. If an occasional first rotational speed value is lower than the predetermined value during the predetermined number of times, the count can be restarted, or the first rotational speed value lower than the predetermined value can be discarded and the count can continue.

[0102] To address the processing resource constraints of the control device, in some embodiments, the attitude change amount may include a first-direction attitude change amount, a second-direction attitude change amount perpendicular to the first-direction attitude change amount, and a third-direction attitude change amount perpendicular to both the first-direction and second-direction attitude change amounts. The direction of the first-direction attitude change amount can be arbitrarily defined as the line connecting the tool accessory and the attitude sensing device. In other embodiments, other directions may also be defined as the direction of the first-direction attitude change amount.

[0103] Under these conditions, step 150 above may include:

[0104] When the value of the first parameter exceeds the threshold range and the real-time value of the first direction attitude change is higher than the adjusted threshold of the first direction attitude change and / or the real-time value of the second direction attitude change is higher than the adjusted threshold of the second direction attitude change and / or the real-time value of the third direction attitude change is higher than the adjusted threshold of the third direction attitude change, the motor can be controlled to stop.

[0105] For example, given that the attitude change includes attitude changes in three directions, when the value of the first parameter exceeds a threshold range and the real-time value of the attitude change in the first direction is higher than the adjusted threshold for the attitude change in the first direction and / or the real-time value of the attitude change in the second direction is higher than the adjusted threshold for the attitude change in the second direction and / or the real-time value of the attitude change in the third direction is higher than the adjusted threshold for the attitude change in the third direction, the motor can be stopped. In this embodiment, when the value of the first parameter exceeds a threshold range and the real-time value of the attitude change in the first direction is higher than the adjusted threshold for the attitude change in the first direction, or the real-time value of the attitude change in the second direction is higher than the adjusted threshold for the attitude change in the second direction, or the real-time value of the attitude change in the third direction is higher than the adjusted threshold for the attitude change in the third direction, the motor is stopped. Selecting any one of the real-time values ​​of the attitude changes in the three directions that exceeds the threshold is considered determining that the real-time value of the attitude change is higher than the adjusted threshold for the attitude change, and then stopping the motor. In other embodiments, any two of the three directions can be combined and used in conjunction with the attitude change in the other direction for judgment, or the combined value of the attitude changes in the three directions can be used for judgment.

[0106] To facilitate more accurate setting of the initial value of the attitude change, step 120 may include the following processing:

[0107] Step 1: Obtain the attitude change detected by the attitude sensing device within a predetermined time period.

[0108] For example, during the processing in step 120, the control device can pre-acquire the attitude change amount detected by the attitude sensing device within a predetermined time. The predetermined time can be preset and configured in the control device; the predetermined time can be 1 second (s) or other times. In this embodiment, the predetermined time is 1 second. The control device collects and stores the attitude change amount detected by the attitude sensing device within the predetermined time after the motor starts. Of course, this does not mean that the attitude change amount detected by the attitude sensing device later will not be collected; it simply means that the attitude change amount within the predetermined time is collected and processed as the initial value of the attitude change amount. The predetermined time is generally considered to be when the operator has not yet applied the tool attachment to the work surface within the predetermined time, so the working parameter value at this time generally does not exceed the threshold range.

[0109] Step 2: Take the maximum value of the attitude change within the predetermined time as the initial value of the attitude change.

[0110] For example, after acquiring the attitude change amount detected by the attitude sensing device within a predetermined time, the control device can use the maximum value of the attitude change amount within the predetermined time as the initial value of the attitude change amount. The attitude sensing device senses the attitude change amount according to a certain sampling period and sampling frequency. Therefore, within the predetermined time, the attitude change amount sensed by the attitude sensing device can be a series of values ​​acquired by the control device. The control device can compare these series of attitude change amount values ​​and obtain the maximum value as the initial value of the attitude change amount. The maximum value refers to the maximum value of the attitude change amount caused by the vibration due to the difference of the tool attachment when it is not applied to the working surface. The maximum value is selected because the threshold of the subsequent attitude change amount needs to be adjusted based on the initial value of the attitude change amount. However, when a collision actually occurs, the value will inevitably be larger than the adjusted attitude change amount threshold. Therefore, the maximum value is selected here to prevent the attitude change amount threshold from being set too low, which would prevent the protection from being triggered.

[0111] To facilitate the adjustment of the attitude change threshold based on the initial value of the attitude change, step 130 may include:

[0112] The threshold for attitude change is obtained based on the initial value of the attitude change and the influencing factor.

[0113] The influencing factor can be the effect of the power tool's operation and the operator's gripping motion on the initial value of the posture change. The influencing factor is greater than 1, that is, it is an appropriate increase based on the initial value of the posture change. It can be 1.1 or 1.2, depending on the operator's experience and test results.

[0114] For example, when adjusting the attitude change threshold based on the initial value of the attitude change, the control device can obtain the attitude change threshold according to the initial value of the attitude change and the influencing factor. The control device can multiply the initial value of the attitude change by the influencing factor to obtain the attitude change threshold, thereby facilitating the comparison and judgment of the attitude change. The value of the influencing factor can be selected appropriately based on the attitude change obtained from testing and experience.

[0115] In order to process the parameter values ​​of the electric motor and eliminate errors in the parameter values ​​generated during the control of the power tool by the control device, step 130 may include:

[0116] Obtain the parameter sampling values ​​of the motor.

[0117] For example, during the process of acquiring the first parameter value of the motor, the control device can pre-acquire the parameter sampling values ​​of the motor. These parameter sampling values ​​can be detected by an additional parameter detection device, or the control device can directly acquire the internal parameters of the motor. In this embodiment, the real-time parameter sampling values ​​of the motor are obtained by directly acquiring the internal parameters of the motor.

[0118] The first parameter value is obtained by delaying the sampled parameter values.

[0119] For example, after acquiring the parameter sampling values ​​of the motor, the control device can perform delay processing on the parameter sampling values ​​to obtain a first parameter value. The first parameter value after delay processing will have a certain preset time delay relative to the sampling value, and the peak value will also decrease, making the parameter smoother. When the parameter value is a current value, the processed first current value can then participate in the control of the control device, which can reduce the vibration of the motor caused by sudden increases and decreases in the operating current. In the control process of power tools, there are constant speed and constant power processes. In the initial stage of startup, the motor is in a constant speed startup process; under load, the motor is in a constant power process. When the motor is in a constant power process, if the load increases and it is necessary to maintain constant power, the speed needs to be reduced to increase torque. If the operating current changes frequently, i.e., suddenly increases and decreases, the motor frequently switches torque, causing vibration. After processing, sudden increases and decreases in the operating current are suppressed, thus reducing the vibration of the power tool during operation.

[0120] In order to incorporate historical factors from the power tool's operation into the power processing, the corresponding step of delaying the parameter sampling values ​​to obtain the first parameter value includes:

[0121] Get the first parameter value from the history.

[0122] For example, the control device can pre-acquire historical first parameter values ​​before processing the sampled parameter values. These historical first parameter values ​​are pre-stored in a data storage unit, such as a storage device. The historical first parameter values ​​can be first parameter values ​​prior to the current moment, first parameter values ​​from the previous cycle used by the control device, or first parameter values ​​from multiple previous cycles used by the control device.

[0123] The current first parameter value is obtained by processing the parameter sample value and the historical first parameter value.

[0124] For example, after acquiring historical first parameter values, the control device can process the parameter sample values ​​and historical first parameter values ​​to obtain the current first parameter value. At the current moment, the parameter sample values ​​and historical first parameter values ​​are combined to obtain the current first parameter value, thereby fully incorporating historical factors into the processing and reducing the influence of the current parameter sample values ​​on the first parameter value.

[0125] To adjust for the influence of historical factors on parameter values, the corresponding processing of the current first parameter value based on the parameter sample value and the historical first parameter value can include the following steps:

[0126] The current first parameter value is obtained based on the first value and the second value that is positively correlated with the first value.

[0127] For example, the first value is the parameter sampling value with a first set weight, and the second value is the historical first parameter value with a second set weight. Here, the first set weight and the second set weight can be a proportionality coefficient less than 1. The sum of the first set weight and the second set weight is 1, and the positive correlation in this embodiment is an additive coefficient. In this embodiment, the explanation is based on the example that the current first parameter value is affected by the first parameter value of the previous period. The formula representing the first parameter value can be C(N) = a*C(N-1) + b*ΔC(N). Where N is the sampling period time point, which is a positive integer; C(N-1) can be the first parameter value of the previous period, and ΔC(N) is the parameter sampling value. a is the weight corresponding to the first parameter value of the previous period, i.e., the second set weight, and b is the weight corresponding to the parameter sampling value, i.e., the first set weight. When N=1, the value of C(N-1) is set to 0.

[0128] In some embodiments, the first set weight is less than the second set weight, thereby making the influence of historical first parameter values ​​on the first parameter value greater than the influence of parameter sample values. In this embodiment, the current first parameter value is calculated using a historical value of the first parameter value. In other embodiments, the current first parameter value can also be calculated using two or more historical values ​​of the first parameter value. In this case, when there is no corresponding value for a historical first parameter value, the historical first parameter value is set to 0. For example, the parameter value can be a current value or a rotational speed value.

[0129] To facilitate stopping the motor, the power supply to the motor can be cut off, or a reverse current can be applied to the motor after the power supply is cut off, which can promote the motor to stop quickly and facilitate the motor to stop rapidly.

[0130] Referring to Figure 2, which shows a schematic diagram of the main body of a power tool according to one embodiment of this application, and Figure 3, which shows a schematic diagram of the control logic of a power tool according to one embodiment of this application, this application uses an angle grinder as an example for illustration. In some embodiments, the power tool includes a housing 201, a motor 202, a tool attachment 203, a posture sensing device 204, a work detection device 205, a control device 206, and a power supply device 207, wherein the motor 202 is housed in the housing 201. The tool attachment 203 may be a disc-shaped attachment such as a grinding disc or a cutting disc. In this embodiment of the application, the tool attachment 203 is described as a grinding disc. The tool attachment 203 may be mounted on the output shaft of the motor 202 or the output shaft of the transmission mechanism connected to the motor 202 and driven to rotate by the motor 202.

[0131] The attitude sensing device 204 is installed inside or on the housing 201, at least partially enclosed within the housing 201, and is configured to detect changes in the attitude of the housing 201. These changes can be generated by vibration of the tool accessory 203 or by impact or external force on the housing 201. The work detection device 205 can be installed inside the housing 201 or can be part of the control device 206. The work detection device 205 is configured to detect the operating parameters of the motor 202 and output a work signal, which can be a current value, a rotational speed value, etc.

[0132] The control device 206 can be installed within and at least partially housed by the housing 201. The control device 206 is capable of outputting a control signal in response to a working signal and the processing result of attitude change. The power supply 207 can be an AC power supply or a DC power supply, and the power supply 207 can be installed on the housing 201. The power supply 207 is capable of selectively providing electrical energy to the motor 202 based on the control signal. The control device 206 controls the start and stop of the motor 202 by controlling the power supply 207.

[0133] In some embodiments, the control device 206 includes a parameter processing module 208, which is configured to perform delay processing on the parameter sampled value and is also configured to store historical values ​​of the first parameter value to calculate the current first parameter value.

[0134] In some embodiments, the control device 206 further includes an attitude change processing module 209, which is configured to adjust the threshold of the attitude change based on the initial value of the attitude change, so as to facilitate comparison and control.

[0135] In some embodiments, the threshold of the attitude change is adjusted by obtaining the initial value of the attitude change detected by the attitude sensing device 204, thereby controlling the motor 202 more accurately, improving the detection accuracy, and reducing the probability of miscontrol.

Claims

1. An angle grinder control method for an angle grinder, the angle grinder comprising an electric motor, a control device configured to control rotation of the electric motor, and a posture sensing device, the angle grinder control method being performed by the control device. The angle grinder control method comprises: controlling the motor to start; obtaining an initial value of a posture change amount of the angle grinder detected by the posture sensing device; adjusting a threshold value of the posture change amount of the angle grinder based on the initial value of the posture change amount; obtaining a first parameter value of the motor and a real-time value of the posture change amount of the angle grinder; controlling the motor to stop in response to the first parameter value exceeding a threshold range and the real-time value of the posture change amount being higher than the adjusted threshold value of the posture change amount.

2. The angle grinder control method of claim 1, wherein, The posture change amount comprises a first direction posture change amount, a second direction posture change amount perpendicular to the first direction posture change amount, and a third direction posture change amount perpendicular to the first direction posture change amount and the second direction posture change amount, respectively. The controlling the motor to stop in response to the first parameter value exceeding a threshold range and the real-time value of the posture change amount being higher than the adjusted threshold value of the posture change amount comprises: controlling the motor to stop in response to the first parameter value exceeding a threshold range and at least one of the following conditions being met: the real-time value of the first direction posture change amount being higher than the adjusted threshold value of the first direction posture change amount, the real-time value of the second direction posture change amount being higher than the adjusted threshold value of the second direction posture change amount, and the real-time value of the third direction posture change amount being higher than the adjusted threshold value of the third direction posture change amount.

3. The angle grinder control method of claim 1, wherein, The obtaining the initial value of the posture change amount of the angle grinder detected by the posture sensing device comprises: obtaining posture change amounts detected by the posture sensing device within a predetermined time; taking a maximum value of the posture change amounts within the predetermined time as the initial value of the posture change amount. The obtaining the first parameter value of the motor comprises: obtaining a parameter sample value of the motor; obtaining the first parameter value by performing time delay processing on the parameter sample value. The obtaining the first parameter value by performing time delay processing on the parameter sample value comprises: obtaining a historical first parameter value; obtaining the current first parameter value based on the parameter sample value and the historical first parameter value. The obtaining the current first parameter value based on the parameter sample value and the historical first parameter value comprises: obtaining the current first parameter value according to a first value and a second value positively correlated with the first value; wherein the first value is a parameter sample value of a first set weight, and the second value is a historical first parameter value of a second set weight; the first set weight is smaller than the second set weight. The adjusting the threshold value of the posture change amount of the angle grinder based on the initial value of the posture change amount comprises: obtaining the threshold value of the posture change amount according to the initial value of the posture change amount and an influence factor; wherein the influence factor is greater than 1; the first parameter value is a current value or a rotational speed value.

4. An angle grinder, comprising: a housing; a motor accommodated in the housing; a grinding disc driven by the motor; a posture sensing device at least partially accommodated by the housing and configured to detect a posture change amount of the housing; ​ a working detecting device configured to detect a working parameter of the motor and output a working signal; a control device configured to output a control signal in response to the working signal and a processing result of the attitude change amount; a power supply device configured to selectively provide power to the motor in response to the control signal; the control device is configured to perform the angle grinder control method according to any one of claims 1-3.

5. The angle grinder of claim 4, wherein, the control device comprises a parameter processing module configured to perform time delay processing on the parameter sample value; the parameter processing module is further configured to store historical values of the first parameter value and calculate a current first parameter value; the control device further comprises an attitude change amount processing module configured to adjust a threshold value of the attitude change amount based on an initial value of the attitude change amount.

6. A power tool control method for a power tool, the power tool comprising a motor, a control device configured to control rotation of the motor, and a posture sensing device, the power tool control method being executed by the control device. the electric tool control method comprises: controlling the motor to start; obtaining an initial value of the attitude change amount of the electric tool detected by the attitude sensing device; adjusting a threshold value of the attitude change amount of the electric tool based on the initial value of the attitude change amount; obtaining a first parameter value of the motor and a real-time value of the attitude change amount of the electric tool; controlling the motor to stop in response to the first parameter value exceeding a threshold value range and the real-time value of the attitude change amount being higher than the adjusted threshold value of the attitude change amount.

7. The electric power tool control method according to claim 6, wherein the attitude change amount comprises a first direction attitude change amount, a second direction attitude change amount perpendicular to the first direction attitude change amount, and a third direction attitude change amount perpendicular to the first direction attitude change amount and the second direction attitude change amount, respectively; the controlling the motor to stop in response to the first parameter value exceeding a threshold value range and the real-time value of the attitude change amount being higher than the adjusted threshold value of the attitude change amount comprises: controlling the motor to stop in response to the first parameter value exceeding a threshold value range and at least one of the following conditions being met: the real-time value of the first direction attitude change amount being higher than the adjusted threshold value of the first direction attitude change amount, the real-time value of the second direction attitude change amount being higher than the adjusted threshold value of the second direction attitude change amount, and the real-time value of the third direction attitude change amount being higher than the adjusted threshold value of the third direction attitude change amount.

8. The electric power tool control method according to claim 6, wherein the obtaining the initial value of the attitude change amount of the electric tool detected by the attitude sensing device comprises: obtaining the attitude change amount detected by the attitude sensing device within a predetermined time; taking the maximum value of the attitude change amount within the predetermined time as the initial value of the attitude change amount.

9. The electric power tool control method according to claim 6, wherein the obtaining the first parameter value of the motor comprises: obtaining a parameter sample value of the motor; performing time delay processing on the parameter sample value to obtain the first parameter value.

10. The electric power tool control method according to claim 9, wherein the performing time delay processing on the parameter sample value to obtain the first parameter value comprises: obtaining a historical first parameter value; processing the parameter sample value and the historical first parameter value to obtain a current first parameter value.

11. The electric power tool control method according to claim 10, wherein the processing the parameter sample value and the historical first parameter value to obtain a current first parameter value comprises: obtaining the current first parameter value according to a first value and a second value positively correlated with the first value; wherein the first value is a parameter sampling value of a first set weight, and the second value is a historical first parameter value of a second set weight; the first set weight is less than the second set weight.

12. The electric power tool control method according to claim 6, wherein adjusting the threshold of the attitude change amount based on the initial value of the attitude change amount, comprises: obtaining the threshold of the attitude change amount according to the initial value of the attitude change amount and an influence factor; wherein the influence factor is greater than 1; the first parameter value is a current value or a rotating speed value.

13. An electric tool, comprising: a housing; an electric motor accommodated in the housing; a tool accessory driven by the electric motor; an attitude sensing device at least partially accommodated in the housing and configured to detect an attitude change amount of the tool accessory and the housing; a working detecting device configured to detect a working parameter of the electric motor and output a working signal; a control device configured to output a control signal in response to the working signal and a processing result of the attitude change amount; a power supply device configured to selectively provide electric energy to the electric motor in response to the control signal; the control device is configured to execute the electric tool control method according to any one of claims 6-12.

14. The power tool of claim 13, wherein, the control device comprises a parameter processing module configured to perform time delay processing on the parameter sampling value; the parameter processing module is further configured to store historical values of the first parameter value and calculate a current first parameter value; the control device further comprises an attitude change amount processing module configured to adjust the threshold of the attitude change amount based on the initial value of the attitude change amount.

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