Hand-held power tool with kickback detection and method of detecting a kickback condition of a hand-held power tool

Abstract

Disclosed herein are handheld power tools with kickback detection and methods of detecting a kickback condition of a handheld power tool. The method includes moving an implement of the handheld power tool in an implement motion plane and detecting a motion of the handheld power tool. The method also includes determining that the kickback condition exists based at least in part on the motion of the handheld power tool. In some embodiments, the handheld power tool is a circular saw including a user actuated assembly. The user actuated assembly includes a motion sensor, a controller, and a motor. The circular saw also includes a workpiece support and a pivot. The motion sensor is configured to detect an acceleration along an acceleration detection axis that extends from a pivot axis of the pivot to a threshold pivot axis-acceleration axis distance of 4 cm or less.

Description

[0001] Related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 151,205, filed February 19, 2021, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] This disclosure generally relates to handheld power tools with recoil detection and / or methods for detecting recoil conditions of handheld power tools. Background Technology

[0004] Power tools (e.g., circular saws) may behave unpredictably under certain operating conditions, such as by rapidly accelerating in unexpected and / or unintended ways. This behavior may be referred to herein as a "kickback condition" of the power tool. As an example, when cutting a workpiece with a circular saw, the workpiece can extend along both lateral sides of the circular saw blade. If the workpiece is allowed to engage with and / or clamp the sides of the circular saw blade, the friction between the sides of the blade and the workpiece can power the saw's kickback. As another example, if the circular saw blade accidentally cuts deep into the workpiece and / or enters atypically hard or soft areas of the workpiece, the change in force acting on the circular saw may manifest as a kickback condition.

[0005] Mechanisms for detecting and responding to recoil have been developed. However, these mechanisms may be specific to a particular type or category of power tool. For example, detecting recoil in stationary power tools (which are typically not moved by the user during operation) can be simpler than detecting the corresponding recoil in handheld power tools (which may undergo a variety of different movements during operation). Therefore, there is a need for improved handheld power tools with recoil detection and / or methods for detecting recoil in handheld power tools. Summary of the Invention

[0006] This document discloses a handheld power tool with recoil detection and a method for detecting recoil in the handheld power tool. In some embodiments, the method includes moving the implement of the handheld power tool within a plane of motion, detecting the movement of the handheld power tool, and applying a spoofing parameter. These methods also include determining the presence of recoil based at least in part on the movement of the handheld power tool as a verification parameter and the spoofing parameter.

[0007] In some embodiments, the method includes rotating the circular saw blade in a plane of blade rotation and detecting the motion of the circular saw. Detecting the motion may include detection in an acceleration detection plane parallel to and / or co-linear with the plane of blade rotation. Additionally or alternatively, detecting the motion may include detecting the direction of acceleration of the circular saw in the acceleration detection plane. Additionally or alternatively, detecting the motion may include detecting the angular velocity of the circular saw about at least one rotational detection axis extending in the acceleration detection plane. The method also includes determining the presence of a recoil condition based at least in part on the motion of the circular saw. Determining the presence of a recoil condition may include determining when the magnitude of the circular saw's acceleration is greater than a threshold acceleration value, when the direction of the circular saw's acceleration is within a threshold direction range, and / or when the angular velocity of the circular saw is greater than a threshold angular velocity value.

[0008] A handheld power tool includes a circular saw, which includes a user-actuated component. The user-actuated component includes a motion sensor, a controller, and a motor. The motion sensor is configured to detect movement of the user-actuated component and generate a motion signal indicative of that movement. The controller is programmed to control the operation of the circular saw based at least in part on the motion signal. The motor includes a motor shaft configured to rotate about an axis of rotation. The circular saw also includes a workpiece support configured to position the workpiece and the circular saw relative to each other when the circular saw cuts a workpiece. The circular saw also includes a pivot. The user-actuated component is pivotally coupled to the workpiece support via the pivot; and the user-actuated component and the workpiece support are configured to be operably rotated relative to each other about a pivot axis of the pivot. The motion sensor is configured to detect acceleration along an acceleration detection axis extending from the pivot axis to a threshold pivot-acceleration axis distance of up to 4 cm. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of an example of a circular saw according to this disclosure.

[0010] Figure 2 This is another schematic diagram of an example of a circular saw according to this disclosure.

[0011] Figure 3 This is a schematic diagram of an example of a handheld circular saw according to the present disclosure in an uncut orientation.

[0012] Figure 4 yes Figure 3 A schematic diagram of a handheld circular saw in the cutting orientation.

[0013] Figure 5 It shows the relative proximity Figure 3 and Figure 4 The graph shows the acceleration measured by the motion sensor on the pivot of the circular saw.

[0014] Figure 6It shows the relative distance Figure 3 and Figure 4 The graph shows the acceleration measured by the motion sensor on the pivot of the circular saw.

[0015] Figure 7 This is a schematic diagram of the recoil of a circular saw according to this disclosure.

[0016] Figure 8 This shows that during the recoil period, the forces are relatively close. Figure 7 The graph shows the acceleration measured by the motion sensor at the trailing edge of the circular saw.

[0017] Figure 9 This shows that during the recoil period, the force is relatively far away. Figure 7 The graph shows the acceleration measured by the motion sensor at the trailing edge of the circular saw.

[0018] Figure 10 This is a schematic diagram of an example of a circular saw according to the present disclosure, which includes a motion sensor having an acceleration detection axis extending through a pivot axis.

[0019] Figure 11 This is a schematic diagram of an example of a circular saw including a circuit board according to the present disclosure.

[0020] Figure 12 This is a schematic diagram of an example of a circular saw according to the present disclosure, which includes a pivot near the leading edge of the circular saw and shows a circular saw in an uncut orientation.

[0021] Figure 13 yes Figure 12 A schematic diagram of a circular saw in the cutting orientation.

[0022] Figure 14 This is a flowchart illustrating an example of a method for detecting the recoil condition of a circular saw according to the present disclosure.

[0023] Figure 15 An example is shown of the magnitude of the acceleration of a circular saw that can be detected by the circular saw and / or method according to this disclosure.

[0024] Figure 16 An example is shown of the direction of acceleration of a circular saw that can be detected by the circular saw and / or method according to this disclosure.

[0025] Figure 17 An example of the angular velocity of a circular saw that can be detected by the circular saw and / or method according to this disclosure is shown.

[0026] Figure 18 An example is shown of the angular velocity of a circular saw blade that can be detected by the circular saw and / or method according to this disclosure.

[0027] Figure 19An example is shown of the power consumption of a circular saw motor, which can be detected by the circular saw and / or method according to this disclosure.

[0028] Figure 20 Examples of spoofed linear acceleration components that can be detected and / or utilized by circular saws and / or methods according to this disclosure are shown.

[0029] Figure 21 Examples of spoofed angular velocity components that can be detected and / or utilized by circular saws and / or methods according to this disclosure are shown. Detailed Implementation

[0030] Figures 1 to 21 Examples of handheld power tools 8 such as a circular saw 10, components and / or features of the circular saw 10, parameters and / or methods 300 measured during operation of the circular saw 10 are provided according to this disclosure. Figures 1 to 21 Each figure in the document uses the same numbers to label elements that have similar or at least substantially similar purposes, and these elements may be disregarded herein. Figures 1 to 21 Each of these is discussed in detail. Similarly, in Figures 1 to 21 Each element in the diagram may not be labeled, but for consistency, the associated reference numerals may be used herein. This document refers to... Figures 1 to 21 One or more of the elements, components and / or features discussed herein may be included without departing from the scope of this disclosure. Figures 1 to 21 Any one of the diagrams and / or with Figures 1 to 21 any one Figure 1 Used in this way. Generally, elements that may be included in a particular embodiment are shown in solid lines, while optional elements are shown in dashed lines. However, elements shown in solid lines may not be necessary for all embodiments, and in some embodiments, they may be omitted without departing from the scope of the invention.

[0031] Figures 1 to 4 , Figure 7 , Figures 10 to 13 This is a schematic diagram of an example of a handheld power tool 8 according to this disclosure. For simplicity, and... Figures 1 to 4 , Figure 7 , Figures 10 to 13In this document, the handheld power tool 8 is shown as a circular saw 10. However, as discussed in more detail herein, within the scope of this disclosure, the components, features, and / or methods disclosed herein may be included in and / or used with other types of handheld power tools 8. Examples of such handheld power tools 8 include rotary handheld power tools that rotate the tool relative to a workpiece. Examples of such rotary handheld power tools include rotary cutters, grinders, polishers, and / or drills. Examples of tools used for such rotary handheld power tools include cutting heads, milling cutters, abrasive pads, grinding wheels, and / or drill bits.

[0032] As in Figures 1 to 4 , Figure 7 , Figures 10 to 13 As shown in the unified diagram, and specifically refer to... Figures 1 to 2 The circular saw 10 includes a workpiece support 40 and a pivot 50. The circular saw 10 also includes a user actuation assembly 100 configured to rotate relative to the workpiece support 40 about the pivot 50 and / or cut a workpiece during operational use of the circular saw. The workpiece support 40 is configured to position the workpiece 90 and the circular saw relative to each other when the circular saw cuts the workpiece, support the remainder of the circular saw relative to the workpiece, support the workpiece relative to the circular saw, and / or position the workpiece relative to the user actuation assembly 100. The workpiece support 40 may include and / or define a component facing side 42 facing the user actuation assembly 100 and / or a component opposite side 44 facing away from the user actuation assembly. The component facing side 42 may also be referred to herein as the user actuation assembly facing side 42.

[0033] In some examples of the circular saw 10, such as when the circular saw 10 includes a miter saw, a rocker arm saw, a cleaving saw, and / or a beveling saw, when the circular saw is used to cut a workpiece, the workpiece 90 can be positioned on the component facing side 42 and / or can be supported by the component facing side 42. In some examples of the circular saw 10, such as when the circular saw 10 includes a plunge saw and / or a track saw, when the circular saw is used to cut a workpiece, the workpiece 90 can be positioned on the component opposite side 44 and / or the circular saw can be supported by the workpiece via a workpiece support.

[0034] The user actuation assembly 100 can be pivotally coupled to the workpiece support 40 via a pivot 50. Furthermore, the user actuation assembly 100 and the workpiece support 40 can be configured to operably rotate, twirl, and / or pivot relative to each other about a pivot axis 52 of the pivot 50. This rotation is achieved through… Figure 1 and Figure 2 This can be explained by the transition between them.

[0035] In some examples, this rotation can be used to selectively engage the circular saw blade 170 of the user-actuated component 100 with the workpiece 90, for example, to cut the workpiece with the rotating circular saw blade. As an example, and as... Figure 1 and Figure 2 As shown in the transition, this rotation can be used to selectively change the area on the opposite side 44 of the workpiece support 40 where the circular saw blade extends, the extent to which the circular saw blade extends on the opposite side of the workpiece, and / or the cutting depth of the circular saw blade.

[0036] In some examples, such as when the circular saw 10 includes a handheld circular saw configured to be held by a user when used for cutting a workpiece, the circular saw may have and / or define a front region 22 and a rear region 26. The front region 22 may be configured to lead, be in front of and / or initiate contact with the workpiece when cutting the workpiece with the circular saw, for example, when the user causes the circular saw to pass through the workpiece. The rear region 26 may be configured to follow the front region and / or be behind when cutting the workpiece with the circular saw.

[0037] As in Figure 1 and Figure 2 as well as Figure 12 and Figure 13 As shown by the solid line, pivot 50 can be positioned within and / or near the front region 22. Alternatively, as Figure 1 and Figure 2 as well as Figure 3 and Figure 4 , Figure 7 , Figure 10 and Figure 11 As shown by the dashed line, the pivot 50 may be located within and / or near the rear region 26. Alternatively, the pivot 50 may be located within the end of the circular saw 10, such as the front region 22 or the rear region 26. Alternatively, the front region 22 may define a leading edge 24, the rear region 26 may define a trailing edge 28, and the pivot axis 52 may be within a threshold edge distance of the leading or trailing edge. Examples of threshold edge distances include distances of at least 1 millimeter (mm), at least 5 mm, at least 1 centimeter (cm), at least 2 cm, at least 4 cm, up to 10 cm, up to 8 cm, up to 6 cm, and / or up to 4 cm.

[0038] The user actuation component 100 includes a motion sensor 110 and may include a controller 120. The motion sensor 110 may be configured to detect movement of the user actuation component and / or generate a motion signal 112 that may indicate movement of the user actuation component. Alternatively, and as discussed in more detail herein, the motion sensor 110 may be configured to detect movement of the user actuation component 100 that may indicate a recoil condition of the circular saw and / or the initiation of a recoil condition. Similar to pivot 50, the motion sensor 110 may be located within the front region 22 and / or the rear region 26 of the circular saw.

[0039] As used herein, the phrase "recoil condition" can refer to a condition in which a circular saw or at least one area of ​​a circular saw or a user-actuated component moves or is induced to move in an unexpected and / or unpredictable manner during operational use of the circular saw to cut a workpiece. Such movement may include unexpected linear and / or rotational movements and / or accelerations of the circular saw, and may startle the user of the circular saw and / or damage the workpiece. The circular saws and methods disclosed herein can be configured to detect one or more parameters that may indicate the initiation of a recoil condition or the initial stage of a recoil condition, and to respond to such detection in a manner that mitigates or reduces the magnitude of the circular saw's movement. Therefore, the circular saws and methods disclosed herein can reduce the likelihood of startling the user of the circular saw and / or damaging the workpiece due to a recoil condition.

[0040] The controller 120 may be adapted, configured, and / or programmed to control the operation of the circular saw 10 based at least in part on the motion signal 112. As an example, and also as discussed in more detail herein, the controller 120 may be programmed to determine when a backlash condition exists or has been initiated, and to respond to the backlash condition, such as mitigating the effects of the backlash condition, reducing the likelihood of damage to the workpiece due to the backlash condition, and / or reducing the likelihood of injury to the user due to the backlash condition.

[0041] like Figure 1 and Figure 2 As shown by the dashed line, the user actuation component 100 of the circular saw 10 may include a gripping area 130. The gripping area 130, when present, can be configured to be gripped and / or held by the user of the circular saw during operation of the circular saw cutting a workpiece. In some examples, the gripping area 130 may be located within and / or near the front region 22 of the circular saw 10. In some examples, the gripping area 130 may be located within and / or near the rear region 26 of the circular saw 10.

[0042] For example Figure 1 and Figure 2As shown by the dashed lines, the user actuation component 100 of the circular saw 10 may include at least one switch 140. The switch 140, when present, can be configured to be selectively actuated by the user, for example, selectively initiating operation of the circular saw, selectively enabling the circular saw to operate, and / or selectively applying current to at least one other component of the circular saw, such as the controller 120. As shown, the switch 140 may be close to the gripping area 130, for example, to allow and / or facilitate selective actuation of the switch by the user when the user grips the gripping area of ​​the circular saw. Examples of the switch 140 include a trigger switch, a normally open switch, and / or a single-throw switch.

[0043] like Figure 1 and Figure 2 As shown by the dashed line, the user actuation component 100 of the circular saw 10 may include a motor 150. The motor 150, when present, may include a motor shaft 152 and / or be configured to rotate the motor shaft about an axis of rotation 154. Examples of the motor 150 include an electric motor, an AC electric motor, a DC electric motor, a brushless DC electric motor, a variable speed motor, and / or a single-speed motor.

[0044] For example Figure 1 and Figure 2 As shown by the dashed line, the user actuation assembly 100 of the circular saw 10 may include a spindle 160. The spindle 160, when present, may be operatively attached to the motor shaft 152 and / or configured to receive and / or operatively attach the circular saw blade to the motor shaft and / or the user actuation assembly. Additionally or alternatively, the spindle 160 may be configured to drive the circular saw blade 170 or to rotate the circular saw blade 170 within the blade's plane of rotation. The blade's plane of rotation may be parallel to or at least substantially parallel to... Figure 1 and Figure 2 The XZ plane. Examples of spindle 160 include any suitable clamp, compression mechanism, washer, bushing, gasket and / or threaded hole that is operatively attached to, defined by and / or mechanically communicated with motor shaft 152.

[0045] like Figure 1 and Figure 2As shown by the dashed line, the user actuation component 100 of the circular saw 10 may include and / or be configured to operably receive a circular saw blade 170. The circular saw blade 170, when present, may be operably attached to the circular saw via a spindle 160 and / or may be configured to selectively rotate in the blade's plane of rotation to cut a workpiece. The circular saw blade 170 typically includes a disc defining a central opening and a cutting edge defined on the outer circumference of the disc, the disc being a metal disc, the central opening being sized to receive the spindle 160. As an example, the cutting edge may include multiple cutting teeth and / or abrasive material. Examples of circular saw blades 170 include metal circular saw blades, abrasive circular saw blades, carbide tooth circular saw blades, diamond circular saw blades, longitudinal cutting circular saw blades, transverse cutting circular saw blades, combination circular saw blades, special circular saw blades, metal cutting circular saw blades, tile cutting circular saw blades, and / or composite material cutting circular saw blades.

[0046] Figure 1 and Figure 2 The user-actuated component 100 is shown to include a motion sensor 110 and a controller 120. Figure 1 and Figure 2 The user actuation component 100 is also shown to optionally include several additional components, such as a gripping area 130, a switch 140, a motor 150, a spindle 160, and / or a circular saw blade 170. To detect movement of the user actuation component, a motion sensor 110 is typically associated with and / or at least indirectly attached to the user actuation component.

[0047] However, within the scope of this disclosure, any suitable one and / or more components of the circular saw 10 (such as those disclosed herein) can be incorporated into the circular saw in any suitable manner. As an example, one or more components of the circular saw 10 (e.g., controller 120, gripping area 130, switch 140, motor 150, spindle 160, and / or circular saw blade 170) can be associated with and / or attached to the workpiece support 40 and / or pivot 50. Additionally or alternatively, one or more components of the circular saw 10 can be indirectly attached to the user actuation assembly 100, for example, via the workpiece support 40 and / or pivot 50.

[0048] The motion sensor 110 may include any suitable structure that is adapted, configured, designed, and / or constructed to detect motion of a user-actuated component and / or generate motion signals. As an example, the motion sensor may include and / or may be a microelectromechanical system (MEMS) motion sensor.

[0049] As discussed, motion sensor 110 may form part of user actuation assembly 100. Alternatively, motion sensor 110 may be configured to rotate with user actuation assembly 100 about pivot 52 and / or relative to workpiece support 40. Such a configuration may allow and / or facilitate the measurement or direct measurement of motion of circular saw 10, which may act on, be experienced by, and / or be in contact with the user of the circular saw. Additionally or alternatively, such a configuration may also allow and / or facilitate the measurement or direct measurement of motion or translational motion of circular saw blade 170.

[0050] However, such a configuration may also present additional challenges and / or make it more difficult to detect recoil and / or distinguish recoil from other conditions that may occur during normal or non-recoil operation of the circular saw. As an example, the cutting action of the circular saw 10 in the form of a cutting saw 20 according to this disclosure is achieved by... Figure 3 The configuration shown is to Figure 4 The configuration change is illustrated. During this cutting action or movement, when the cutting saw... Figure 3 The non-cut orientation 30 shown is transformed to Figure 4 When the cutting orientation 32 is shown, the user actuation component 100 rotates relative to the workpiece support 40 via the pivot 50. For example... Figure 5 and Figure 6 As shown in the graph, the motion sensor 110 of the user actuation component 100 may experience acceleration during the initiation of the cutting action shown in 210 and also during the termination of the cutting action shown in 212. It may not be desirable for the controller 120 to characterize this expected acceleration as a recoil condition. Therefore, and as discussed in more detail herein, the controller 120 may require the detected acceleration to have a specific magnitude, may require the detected acceleration to have a specific direction, and / or may utilize one or more additional parameters to determine and / or establish that the detected acceleration of the user actuation component 100 is a result of, or corresponds to, the recoil condition of the circular saw.

[0051] Back Figure 1 and Figure 2The motion sensor 110 can be configured to detect any suitable movement of the user actuation component 100. As an example, the motion sensor can be configured to detect acceleration of the user actuation component along a single detection axis 206 (which may also be referred to herein as acceleration detection axis 206) and / or along multiple detection axes 206 (e.g., two perpendicular detection axes 206 and / or three orthogonal detection axes 206). As another example, the motion sensor can be configured to detect rotation of the user actuation component about a single detection axis 206 (which may also be referred to herein as rotation detection axis 206) and / or about multiple detection axes 206 (e.g., two perpendicular detection axes 206 and / or three orthogonal detection axes 206).

[0052] In some examples, motion sensor 110 may be configured to detect acceleration of user actuation component 100 within or only within the acceleration detection plane. The acceleration detection plane may be perpendicular to or at least substantially perpendicular to the axis of rotation 154, perpendicular to or at least substantially perpendicular to the pivot axis 52, and / or parallel to or at least substantially parallel to the blade rotation plane in which the circular saw blade rotates during circular saw operation. As a specific example, the acceleration detection plane may be parallel to or at least substantially parallel to... Figure 1 and Figure 2 The XZ plane.

[0053] In some examples, motion sensor 110 may be configured to detect rotation of user actuation component 100 about or only about a detection axis 206 extending in the acceleration detection plane. Alternatively, motion sensor 110 may be configured to detect rotation of user actuation component 100 about the same detection axis 206 of motion sensor 110, which is used to detect acceleration of user actuation component 100 in the acceleration detection plane.

[0054] The position of the motion sensor 110 on the user actuation component 100 can affect the sensitivity of the motion sensor to various movements of the user actuation component. For example, such as... Figure 3 and Figure 4 As shown, when the motion sensor 110 is positioned relatively closer to the pivot 50 (as shown by the solid line), its sensitivity to the cutting motion of the infeed saw 20 may be relatively lower compared to when it is positioned relatively farther from the pivot 50 (as shown by the dashed line). This is achieved through... Figure 5 Compared to the curve graph Figure 6 The increase in the magnitude of acceleration at points 210 and 212 in the graph is used to illustrate this. Figure 6 It shows the result of Figure 3 and Figure 4The dashed line shows the acceleration measured by motion sensor 110, which defines a relatively large threshold pivot-sensor distance 56. In contrast, Figure 5 The acceleration measured by motion sensor 110 is shown as a solid line and defines a relatively small threshold pivot-sensor distance 56.

[0055] As another example, and as Figure 7 As shown, when the motion sensor 110 is positioned relatively closer to the trailing edge 28 (i.e., the threshold trailing edge-sensor distance 57 is relatively small), the motion sensor may be relatively more sensitive to the recoil motion of the circular saw compared to when the motion sensor is positioned relatively farther from the trailing edge 28 (i.e., the distance 57 is relatively large). Figure 7 In the figure, the recoil motion indicated by 34 causes the circular saw to move from the orientation shown by the dashed line to the orientation shown by the solid line. As shown, the motion sensor 110, which is relatively closer to the trailing edge 28, moves a larger distance 58 compared to the distance 59 that the motion sensor 110 moves relative to the trailing edge 28.

[0056] Figure 8 The acceleration measured by motion sensor 110, which is relatively closer to the trailing edge 28 (i.e., defining a relatively small threshold trailing edge-sensor distance 57), is shown during the recoil motion indicated by 34. Figure 9 The figure shows the acceleration measured by motion sensor 110 during the recoil motion indicated by 34, which is relatively far from the trailing edge 28 (i.e., defining a relatively large threshold trailing edge-sensor distance 57). As shown, with... Figure 9 compared to, Figure 8 The magnitude of the acceleration signal in the middle is significantly larger.

[0057] With this in mind, it may be necessary to position the motion sensor 110 close to the pivot 50 and / or close to the trailing edge 28. This configuration reduces the motion sensor's sensitivity to normal circular saw movement while increasing its sensitivity to recoil conditions. Therefore, in some examples, the motion sensor 110 may be positioned at a distance 56 from the pivot axis 52, such as... Figures 1 to 4 As shown. Examples of distance 56 include distances of at least 1cm, at least 2cm, at least 3cm, at least 4cm, at least 5cm, at least 6cm, at least 7cm, at least 8cm, up to 20cm, up to 18cm, up to 16cm, up to 14cm, up to 12cm, up to 10cm, up to 9cm, up to 8cm, up to 7cm, up to 6cm, up to 5cm, up to 4cm, up to 3cm, up to 2cm and / or up to 1cm.

[0058] In some examples, motion sensor 110 may be configured to detect acceleration along acceleration detection axis 206, along a single acceleration detection axis 206, and / or only along a single acceleration detection axis 206. A relatively short distance between acceleration detection axis 206 and pivot axis 52 can reduce the sensitivity of motion sensor 110 to rotation about the pivot axis while still allowing the motion sensor to detect the recoil motion of the circular saw. With this in mind, and in some examples, the distance or minimum distance between acceleration detection axis 206 and pivot axis 52 may be a threshold pivot axis-acceleration axis spacing distance. Examples of threshold pivot axis-acceleration axis spacing distances include distances of at least 1 mm, at least 2 mm, at least 3 mm, at least 4 mm, at least 5 mm, at least 6 mm, at least 7 mm, at least 8 mm, at least 9 mm, at least 1 cm, up to 4 cm, up to 3 cm, up to 2 cm, up to 1 cm, up to 8 mm, up to 6 mm, up to 4 mm, up to 2 mm, and / or up to 1 mm.

[0059] When pivot 50 is located relatively closer to leading edge 24, and as Figure 12 and Figure 13 As shown, it may be necessary to position the motion sensor 110 relatively far from the pivot 50 and / or relatively closer to the trailing edge 28. This configuration can both reduce the motion sensor's sensitivity to normal circular saw movement and increase its sensitivity to recoil conditions. Therefore, in some examples, the motion sensor 110 may be positioned at a distance 56 from the pivot 52, such as... Figure 1 and Figure 2 As shown in the figure. In such an example, distance 56 includes distances of at least 5cm, at least 6cm, at least 7cm, at least 8cm, up to 20cm, up to 18cm, up to 16cm, up to 14cm, up to 12cm, up to 10cm, up to 9cm, up to 8cm, up to 7cm and / or up to 6cm.

[0060] In specific examples, while not all circular saws 10 require this, the motion sensor 110 may be positioned and / or oriented such that the acceleration detection axis 206 may intersect the pivot axis 52, may intersect the pivot axis 50, may extend through the pivot axis, and / or may extend perpendicular to or at least substantially perpendicular to the pivot axis, as shown below. Figure 10 , Figure 12 and Figure 13 As shown. In such a configuration, the motion sensor 110 may not detect or may only detect rotation about the pivot axis 52 at a minimal level, further reducing the sensitivity to the circular saw's entry motion or cutting depth setting, while still allowing the detection of the circular saw's recoil motion.

[0061] In some examples, the acceleration detection axis 206 may extend radially relative to the rotation axis 154 of the motor 150. This configuration can increase the sensitivity of the motion sensor 110 to the acceleration or translational acceleration of the motor shaft 152 and / or the circular saw blade 170.

[0062] In some examples, and such as Figure 1 , Figure 2 and Figure 11 As shown, the user-actuated component 100 may include a circuit board 180, which may include both a controller 120 and a motion sensor 110. This configuration can reduce the costs associated with the construction of the circular saw 10, thereby allowing for more economical production of the circular saw. When both the controller 120 and the motion sensor 110 are located on the same circuit board 180, spatial constraints may dictate that the motion sensor is positioned at a finite distance from the pivot axis 52 and / or the detection axis 206 cannot intersect the pivot axis 52.

[0063] The controller 120 may include any suitable structure that is adapted, configured, designed, constructed, and / or programmed to control the operation of the circular saw at least in part based on the motion signal 112. In some examples, and as discussed, the controller 120 may be programmed to determine that the motion signal 112 indicates a recoil condition of the circular saw. In some examples, the controller 120 may be programmed to determine that the motion signal 112 indicates a recoil condition when the acceleration axis of the acceleration detected by the motion sensor 110 extends through the pivot axis 52. In some examples, the controller 120 may be programmed to perform any suitable one and / or more steps of the method 300 disclosed herein.

[0064] In some examples, the controller 120 can also be programmed to interrupt the rotation of the circular saw blade in response to determining that a recoil condition exists. For example, such as... Figure 1 and Figure 2 As shown, the circular saw 10 may include a brake assembly 80, which may be configured to be selectively actuated to interrupt the rotation of the circular saw blade. In some such examples, the controller 120 may be programmed to actuate the brake assembly 80 in response to a recoil condition and / or in response to determining that a recoil condition exists. As another example, the controller 120 may additionally or alternatively be programmed to interrupt the supply of current to the motor 150 or short-circuit / ground the stator coils of the motor 150 in response to a recoil condition and / or in response to determining that a recoil condition exists.

[0065] The controller 120 may include and / or may be any suitable structure, device, and / or multiple devices that can be adapted, configured, designed, constructed, and / or programmed to perform the functions discussed herein. As an example, the controller 120 may include one or more of an electronic controller, a dedicated controller, a special purpose controller, a display device, a logic device, a storage device, and / or a storage device having a computer-readable storage medium.

[0066] Computer-readable storage media, when present, may also be referred to herein as non-transitory computer-readable storage media. Such non-transitory computer-readable storage media may include, define, contain, and / or store computer-executable instructions, programs, and / or code; and these computer-executable instructions may instruct the circular saw 10 and / or its controller 120 to perform any suitable portion or subset of method 300. Examples of such non-transitory computer-readable storage media include CD-ROMs, magnetic disks, hard disk drives, flash memory, etc. As used herein, storage devices or memories having computer-executable instructions according to this disclosure, devices and / or media, and computer-implemented methods and other methods are considered to be within the scope of patentable subject matter under Title 35, Section 101 of the United States Code.

[0067] like Figure 1 and Figure 2 As shown by the dashed line, the circular saw 10 may include a biasing mechanism 60. The biasing mechanism 60, when present, may be adapted, configured, designed, and / or constructed to bias the user actuation component 100 away from the workpiece support 40 and / or to bias the user actuation component away from the workpiece support for rotation about a pivot axis 52. Examples of the biasing mechanism 60 include resilient members, springs, helical springs, and / or torsion springs.

[0068] For example Figure 1 and Figure 2 As shown by the dashed line, the circular saw 10 may include a snap-in lock 70. The snap-in lock 70, when present, can be configured to be selectively deactivated by the user of the circular saw to selectively allow the user actuation assembly 100 to pivot about the pivot axis 52 and / or toward the workpiece support 40. Examples of the snap-in lock 70 include any suitable latch and / or latch.

[0069] The circular saw 10 may include and / or may be any suitable circular saw. As an example, the circular saw 10 may include and / or may be a handheld circular saw 10, for example, which may be configured to be lifted and / or held by a user when cutting a workpiece with the circular saw. The handheld circular saw 10 may additionally or alternatively be referred to as a portable circular saw 10 and / or a non-fixed circular saw 10. As another example, the circular saw 10 may include and / or may be a semi-fixed circular saw 10. As used herein, the phrase "semi-fixed circular saw" refers to a circular saw that includes a large, heavy, and / or fixed workpiece support 40, which is configured to remain fixed on a support surface when cutting a workpiece with the circular saw. However, because the user actuation assembly 100 is pivotally coupled to the workpiece support 40 via a pivot 50, the user actuation assembly may still experience a backlash condition, which may result in accidental and / or unintended rotation of the user actuation assembly.

[0070] As more specific examples, the circular saw 10 may include an approach saw, a miter saw, a rail saw, a rocker arm saw, a cleaving saw, a sliding miter saw, a beveling saw, and / or a panel saw. When the circular saw 10 includes a rail saw, the rail saw may also include a rail 82 configured to guide the rail saw relative to a workpiece 90. When the circular saw 10 includes a rocker arm saw, the rocker arm saw may also include a support arm 84 configured to guide the rocker arm saw relative to a workpiece. When the circular saw 10 includes a panel saw, the panel saw may also include a frame 86 configured to guide and / or orient the panel saw relative to a workpiece. Some circular saws may include combinations of these elements. As an example, a sliding miter saw may include both a pivot 50 and a frame 86, wherein the user actuation assembly 100 is configured to both rotate relative to a workpiece support 40 about a pivot axis 52 of the pivot 50 and translate relative to the workpiece support 40 along the frame 86.

[0071] Figure 14 This is a flowchart illustrating an example of a method 300 for detecting the recoil condition of a handheld power tool (e.g., a circular saw) according to this disclosure. (See attached diagram.) Figures 1 to 4 , Figure 7 , Figures 10 to 13 Examples of handheld power tools and / or circular saws are disclosed in the handheld power tools and / or circular saws 8 and 10.

[0072] Method 300 includes rotating a circular saw blade at 310 and may include cutting a workpiece at 320. Method 300 also includes detecting circular saw movement at 330 and may include detecting workpiece contact parameters at 340. Method 300 further includes determining the presence of a recoil condition at 350 and may include responding to the determination of the presence of a recoil condition at 360. Method 300 may include determining the presence of a recoil condition at 350 based at least in part on verification parameters, including movement of a handheld power tool and optionally workpiece contact parameters.

[0073] Rotating the circular saw blade at 310 may include rotating the blade within its plane of rotation. Examples of planes of rotation are disclosed herein. This may include rotating the circular saw blade to allow and / or facilitate a cut at 320. Rotation at 310 may be accomplished in any suitable manner. As an example, and as discussed, the circular saw may include a motor comprising a motor shaft configured to rotate about an axis of rotation. Also as discussed, the circular saw may include a spindle for attaching the circular saw blade to the motor shaft. In some such examples, rotation at 310 may include applying or supplying current to the motor to provide power for rotating the motor shaft about the axis of rotation, thereby rotating the circular saw blade via the spindle. Examples of motors, motor shafts, and axes of rotation are disclosed herein with reference to motor 150, motor shaft 152, and axis of rotation 154, respectively. An example of a spindle is disclosed herein with reference to spindle 160. An example of a circular saw blade is disclosed herein with reference to circular saw blade 170.

[0074] The rotation at 310 can be performed during method 300 at any suitable timing and / or sequence. As an example, the rotation at 310 can be performed before, during, and / or concurrently with the cutting at 320, the detection at 330, the detection at 340, the determination at 350, and / or the response at 360.

[0075] Cutting a workpiece at 320° can include cutting the workpiece with a circular saw blade. The cutting at 320° can be accomplished in any suitable manner. As an example, cutting at 320° can include operatively engaging a circular saw blade or a plurality of teeth of a circular saw blade with the workpiece to form and / or define a kerf, slot, and / or groove within the workpiece. Additionally or alternatively, cutting at 320° can include translating and / or rotating the circular saw relative to the workpiece to extend the kerf, slot, and / or groove.

[0076] In some cases, a cut at 320° may also involve establishing a recoil condition. In other words, a recoil condition may occur during a cut at 320°. For example, the circular saw blade may engage with and / or be clamped by the workpiece, causing recoil movement of the circular saw during the recoil condition. As another example, the circular saw blade may cut into an atypically hard or soft area of ​​the workpiece and / or may become stuck in an area of ​​the workpiece, causing recoil movement of the circular saw during the recoil condition.

[0077] The cut at 320 can be performed during method 300 at any suitable timing and / or sequence. As an example, the cut at 320 can be performed after and / or simultaneously with the rotation at 310. As an additional example, the cut at 320 can be performed before, during, or simultaneously with the detection at 330, the detection at 340, the determination at 350, and / or the response at 360.

[0078] Detecting the circular saw's movement at point 330 may include detecting any suitable movement of the circular saw that can indicate recoil and / or be used to predict recoil. Detection at point 330 may be performed during method 300 at any suitable timing and / or sequence. For example, detection at point 330 may be performed after rotation at point 310 and / or cutting at point 320, after initiation of rotation at point 310 and / or cutting at point 320, during rotation at point 310 and / or cutting at point 320, and / or simultaneously with rotation at point 310 and / or cutting at point 320. For another example, detection at point 330 may be performed simultaneously with detection at point 340. For yet another example, detection at point 330 may be performed before determination at point 350 and / or response at point 360. Additionally or alternatively, determination at point 350 and / or response at point 360 may be based on and / or may be at least partially in response to detection at point 330.

[0079] In some examples, the detection at 330 may include detecting the magnitude of acceleration, as shown at 332. The detection at 332 may include detecting the magnitude of acceleration of the circular saw and / or at least one component of the circular saw (e.g., user actuation assembly 100), which will be discussed in more detail herein. In some examples, the detection at 332 may include detection within an acceleration detection plane. The acceleration detection plane may be parallel to or at least substantially parallel to the blade rotation plane and / or may be co-linear with the blade rotation plane. Examples of acceleration detection planes are disclosed herein.

[0080] Detection at 332 may include detecting the magnitude of acceleration in any suitable manner. As an example, and as discussed, the circular saw may include a motion sensor, such as the motion sensor 110 disclosed herein. In such a configuration, detection at 332 may include detection via, through, and / or using a motion sensor.

[0081] In some examples, the detection at 332 may include detecting a first acceleration component in a first direction within the acceleration detection plane, and detecting a second acceleration component in a second direction also within the acceleration detection plane, which may be different from or even perpendicular to the first direction. In some such examples, the magnitude of the acceleration is the magnitude of the vector sum of the first and second acceleration components.

[0082] An example of the magnitude of circular saw acceleration is in Figure 15 The data is presented in the form of time curves and diagrams. For example... Figure 15 As shown in the time-lapse graph, the magnitude of the circular saw's acceleration can increase significantly due to recoil and / or during recoil, as indicated at 220. Therefore, the magnitude of the circular saw's acceleration can indicate recoil and / or can be used to at least partially determine the presence of recoil.

[0083] like Figure 15 As shown in the schematic circular saw 10, the detection at 332 may include detecting a first acceleration component (e.g., acceleration component a). x ), and detect the second acceleration component (e.g., acceleration component a). z In such a configuration, the magnitude of acceleration m can be determined by the vector sum of the first and second acceleration components.

[0084] In some examples, the detection at 330 may include detecting the direction of acceleration, as shown at 334. The detection at 334 may include detecting the direction of acceleration of the circular saw 10 and / or the user actuation assembly 100. In some examples, the detection at 334 may include detection within the acceleration detection plane.

[0085] Detection at 334 may include detecting the direction of acceleration in any suitable manner. As an example, and as discussed, the circular saw may include a motion sensor, such as the motion sensor 110 disclosed herein. In such a configuration, detection at 334 may include detection via, through, and / or using a motion sensor.

[0086] In some examples, the detection at 334 may include detecting a first acceleration component in a first direction within the acceleration detection plane, and detecting a second acceleration component in a second direction also within the acceleration detection plane, which may be different from or even perpendicular to the first direction. In some such examples, the acceleration direction may be the orientation and / or direction of the vector sum of the first and second acceleration components.

[0087] Examples of the magnitude of the direction, angle, or vector orientation of a circular saw are shown in Figure 16 The data is presented in the form of time-based graphs and diagrams. For example... Figure 16As shown in the graph, the direction of acceleration of the circular saw can change significantly due to recoil and / or during recoil, as indicated at 220. Therefore, the direction of acceleration of the circular saw can indicate recoil and / or can be used to at least partially determine the presence of recoil.

[0088] like Figure 16 As shown in the schematic circular saw 10, the detection at 334 may include detecting a first acceleration component (e.g., acceleration component a). x ), and detect the second acceleration component (e.g., acceleration component a). z In such a configuration, the direction of acceleration can be determined, for example, by angle 222, via and / or based on the first and second acceleration components, such as... Figure 16 As shown by "m" in the text.

[0089] The detected angular velocity at 336 may include the detected angular velocity of the circular saw 10 and / or the user actuation assembly 100. In some examples, the detection at 336 may include the detection of angular velocities about and / or around one or more detection axes extending in the acceleration detection plane.

[0090] Detection at 336 may include detecting angular velocity in any suitable manner. As an example, and as discussed, the circular saw may include a motion sensor, such as the motion sensor 110 disclosed herein. In such a configuration, detection at 336 may include detection via, through, and / or using a motion sensor.

[0091] In some examples, the detection at 336 may include detecting a first angular velocity component in a first direction within the acceleration detection plane, and detecting a second angular velocity component in a second direction also within the acceleration detection plane, the second direction being oriented differently from or even perpendicular to the first direction. In some such examples, the angular velocity may be the vector sum of the first and second angular velocity components.

[0092] An example of circular saw angular velocity is in Figure 17 The data is presented in the form of time curves and diagrams. For example... Figure 17 As shown in the graph, the angular velocity of the circular saw can change significantly due to recoil and / or during recoil, as indicated at 220°. Therefore, the angular velocity of the circular saw can indicate recoil and / or can be used to at least partially determine the presence of recoil.

[0093] like Figure 17 As shown in the schematic circular saw 10 on the far left, the detection at 336 may include detecting the first angular velocity component (e.g., angular velocity component w). x ), and detect the second angular velocity component (e.g., angular velocity component w). zIn such a configuration, the angular velocity can be determined by the vector sum of the first and second angular velocity components, such as... Figure 17 The schematic circular saw 10 on the far right is shown at 224.

[0094] As discussed, and for example when handheld power tools include circular saws, handheld circular saws, and / or semi-fixed circular saws, acceleration and / or rotation of the circular saw that may occur during normal operation and / or when the user moves, repositions, and / or resets the circular saw may in some cases be similar to the acceleration and / or rotation experienced during a recoil condition. Therefore, for some circular saws, it may also be beneficial to detect one or more additional parameters that can be used to determine whether the circular saw is currently being used to cut the workpiece and / or whether a recoil condition is actually present.

[0095] With this in mind, method 300 may also include detecting workpiece contact parameters at 340. In such an example, the determination at 350 may also be based at least in part on the detection at 340. In other words, a recoil condition can only exist when the circular saw blade is in contact with the workpiece and / or when the workpiece contact parameters indicate that the circular saw blade is in contact with the workpiece. Therefore, in method 300, contact between the circular saw blade and the workpiece can be used as a necessary condition for the existence of a recoil condition.

[0096] Detecting workpiece contact parameters at 340 may include detecting any suitable workpiece contact parameters that can indicate contact between the circular saw blade and the workpiece. In other words, when the circular saw blade is in contact with the workpiece, the workpiece contact parameters can be within the contact value range. Conversely, when the circular saw blade is spaced apart from or not in contact with the workpiece, the workpiece contact parameters can be within the non-contact value range, which may differ from the contact value range. In such a configuration, the determination at 350 may include determining that a recoil condition exists if or only if the workpiece contact parameters are within the contact value range. In other words, when method 300 includes detection at 340, the workpiece contact parameter having a value within the contact value range may be a prerequisite that must be met before determining the existence of a recoil condition, or for determining the existence of a recoil condition, such as during the determination at 350.

[0097] In some examples, workpiece contact parameters may include and / or may be the angular velocity of the circular saw blade during rotation at 310°, the angular velocity of the circular saw blade, and / or the angular velocity of the motor shaft and / or the angular velocity of the motor shaft. In this configuration, and when the circular saw blade is spaced from the workpiece, the circular saw blade may define a mean free angular velocity, and the range of contact values ​​may include angular velocities below a threshold reduction in mean free angular velocity. Examples of threshold reductions in angular velocity include reductions of at least 20 revolutions per minute (RPM), at least 25 RPM, at least 30 RPM, at least 35 RPM, at least 40 RPM, at least 50 RPM, at least 60 RPM, at least 70 RPM, at least 80 RPM, at least 90 RPM, at least 100 RPM, at least 150 RPM, at least 200 RPM, at least 300 RPM, at least 400 RPM, at least 500 RPM, at least 600 RPM, at least 700 RPM, or at least 800 RPM.

[0098] In other words, the contact between the circular saw blade and the workpiece creates resistance to the rotation of the blade, thereby reducing its angular velocity to a value lower than its mean free angular velocity. Additionally, as discussed, recoil can occur due to the circular saw blade being engaged and / or clamped by the workpiece. This engagement and / or clamping can further reduce the angular velocity of the circular saw blade compared to its mean free angular velocity; and this reduction in the angular velocity of the circular saw blade can be used to indicate that the blade is indeed in contact with the workpiece.

[0099] An example of the time-varying angular velocity of a circular saw blade is... Figure 18 As shown in the figure, the angular velocity of the circular saw blade can be significantly reduced due to recoil and / or during recoil, as indicated at 220. Therefore, the angular velocity of the circular saw blade can be used to at least partially determine the presence of contact between the circular saw blade and the workpiece and / or the presence of recoil.

[0100] The detection of the angular velocity of a circular saw blade can be accomplished in any suitable manner. As an example, detecting the angular velocity of a circular saw blade may include measuring the angular velocity of the blade, for instance, using a rotation counter of the circular saw. As another example, detecting the angular velocity of a circular saw blade may include calculating the angular velocity of the blade, for example, based at least in part on a motor model of the circular saw's motor. In some such examples, calculating the angular velocity of the circular saw blade may include calculating it based at least in part on the magnitude of the current supplied to the motor and / or the magnitude of the voltage of that current.

[0101] In some examples, workpiece contact parameters may include and / or may be the power consumption during the rotation of the circular saw blade at 310. In such a configuration, the motor may be limited to a maximum rated power consumption, and the range of contact values ​​may include power consumption greater than a threshold percentage of the maximum rated power consumption. Examples of threshold percentages of the maximum rated power consumption include 50%, 60%, 70%, 80%, or 90%.

[0102] In other words, the contact between the circular saw blade and the workpiece creates resistance to the rotation of the blade, thereby increasing the motor's power consumption. Additionally, as discussed, recoil can occur due to the circular saw blade being engaged and / or clamped by the workpiece. This engagement and / or clamping can also increase the motor's power consumption; and this increased power consumption can be used as an indication that the circular saw blade is indeed in contact with the workpiece.

[0103] Figure 19 An example of motor power consumption varying over time is shown. As illustrated herein, motor power consumption can increase significantly due to recoil conditions and / or during recoil conditions, indicated at 220. Therefore, motor power consumption can be used to at least partially determine the presence of circular saw blade contact with the workpiece and / or recoil conditions.

[0104] Detecting a motor's power consumption can be done in any suitable manner. As an example, detecting a motor's power consumption may include calculating the motor's power consumption based at least in part on the magnitude of the current supplied to the motor and the magnitude of the voltage across that current.

[0105] In some examples, the circular saw may include a contact detector configured to detect contact between the circular saw blade and the workpiece. In some such examples, the contact detector may be configured to generate and / or generate workpiece contact parameters. Examples of contact detectors include electrical contact detectors, capacitive contact detectors, electromagnetic contact detectors, and / or mechanical contact detectors.

[0106] Determining the presence of recoil at 350° can include determining, establishing, deciding, and / or concluding that recoil exists in any suitable manner and / or based on any suitable information, data, and / or parameters. In some examples, the circular saw may include a controller, such as... Figure 1 , Figure 2 and Figure 11 The controller 120. In some such examples, the controller can be programmed to perform a determination at 350. This may include determining the presence of a recoil condition based at least in part on the motion of the circular saw detected during detection at 330.

[0107] In some examples, determining the value at 350 may include identifying the presence of recoil if or only if the magnitude of the circular saw's acceleration (e.g., it can be determined during detection at 332) is greater than a threshold acceleration value. Examples of threshold acceleration values ​​include at least 1 meter per square second (m / s²). 2 ), at least 2m / s 2 At least 3m / s 2 At least 4m / s 2 At least 6m / s 2 At least 8m / s 2 At least 10m / s 2 At least 12m / s 2 At least 14 m / s 2 At least 16m / s 2 At least 18m / s 2 or at least 20 m / s 2 The acceleration. Examples of accelerations greater than the threshold acceleration value and indicating recoil are given by Figure 15 The area shown by the cross-shaded lines in the curve graph is illustrated.

[0108] In some examples, determining the 350° point may include identifying the presence of recoil when or only when the circular saw's acceleration direction is within a threshold direction range. Examples of threshold direction ranges include directions pointing backward relative to the circular saw's cutting direction, directions pointing towards the trailing edge 28 of the circular saw, and / or directions pointing away from the workpiece being cut by the circular saw, such as... Figure 16 As shown and discussed in this article.

[0109] As more specific examples, a workpiece support may define a workpiece facing side, a workpiece opposite side, a leading edge, and a trailing edge. In some such examples, the threshold direction range may be at least partially perpendicular to the workpiece opposite side of the workpiece support and / or may at least partially point towards the trailing edge of the workpiece support. In some such examples, the threshold direction range may be defined within a quadrant extending between a first vector and a second vector, the first vector pointing towards the trailing edge of the workpiece support and along the workpiece opposite side of the workpiece support, and the second vector intersecting the first vector and pointing perpendicular to the workpiece opposite side of the workpiece support. Examples of such quadrants are... Figure 16 It is shown in the figure and indicated by 226.

[0110] As another, more specific example, the threshold direction range can be within the threshold angle range of the circular saw's cutting direction. Such a threshold angle range can be directed towards the side of the user-actuated component facing away from the workpiece and can be within... Figure 16The threshold angle range is indicated by 222. Examples of threshold angle ranges include angles of at least 80 degrees, at least 90 degrees, at least 100 degrees, at least 110 degrees, at least 120 degrees, at least 130 degrees, at least 140 degrees, at least 150 degrees, at least 160 degrees, up to 200 degrees, up to 180 degrees, up to 170 degrees, up to 160 degrees, up to 150 degrees, up to 140 degrees, up to 130 degrees, up to 120 degrees, up to 110 degrees, and / or up to 100 degrees. Figure 16 The cross-shaded areas in the graph show examples of the threshold direction range within the threshold angle range.

[0111] In some examples, determining the 350° point may include identifying the presence of recoil when or only when the circular saw's angular velocity is greater than a threshold angular velocity value. Examples of threshold angular velocity values ​​include angular velocities of at least 1 degree per second (° / s), at least 2° / s, at least 3° / s, at least 4° / s, at least 6° / s, at least 8° / s, or at least 10° / s. Figure 17 The cross-shaded areas in the graph show examples of angular velocities greater than the threshold angular velocity value. In some examples, the threshold angular velocity value can include the angular velocity that causes the blade of the circular saw's workpiece support to move away from the workpiece, such as... Figure 17 As shown.

[0112] In some examples, determining position 350 may include applying spoofing parameters, analyses, and / or constraints, or even multiple spoofing parameters, analyses, and / or constraints, to the detection at position 330 and / or position 340. In such examples, the determination of position 350 may be based at least in part on spoofing parameters, analyses, and / or constraints.

[0113] Falsified parameters, analyses, and / or constraints can be selected, and / or these parameters, analyses, and / or constraints can be based on the configuration, construction, and / or purpose of the handheld power tool or circular saw. As an example, according to this disclosure, a particular handheld power tool and / or circular saw may have a different overall configuration, construction, and / or layout, and / or may be used differently compared to another handheld power tool or circular saw. Therefore, the handheld power tool and / or circular saw may experience different accelerations and / or rotations compared to other handheld power tools or circular saws, and / or different accelerations and / or rotations may indicate a recoil condition or be necessary for a recoil condition. Therefore, certain handheld power tools or circular saws may utilize one or different falsified parameters, analyses, and / or constraints. Falsified parameters can be applied to determine when a recoil determined by verification parameters is not a true recoil. Applying falsified parameters can improve the sensitivity of verification parameters during the determination process. Therefore, recoil detection can be more sensitive to responses to true recoil while being less prone to erroneous responses to false recoil.

[0114] Examples of spoofed parameters include the linear acceleration component of the circular saw's acceleration, which can be determined, for example, during detection at 330°. The linear acceleration component can point in a specific, defined, and / or predetermined linear acceleration direction. In other words, the linear acceleration component can be a specific subset of the circular saw's overall acceleration, where that specific subset points in a linear acceleration direction. Examples of linear acceleration components are... Figure 20 It is shown in the figure and discussed in more detail in this article.

[0115] The linear acceleration direction may include or be equivalent to any suitable specific, defined, and / or predetermined linear acceleration direction. As an example, the linear acceleration direction may be parallel to or at least substantially parallel to the plane of rotation of the circular saw blade, and / or may be parallel to or at least substantially parallel to the assembly-facing side of the workpiece support of the circular saw. As another example, the linear acceleration direction may be parallel to or at least substantially parallel to the longitudinal axis of the groove defined by the circular saw blade within the workpiece, for example, during a cut at 320°.

[0116] As an additional example, the linear acceleration direction can be within a threshold angle difference that is parallel to the blade rotation plane, parallel to the component face of the workpiece support, and / or parallel to the groove. Examples of threshold angle differences include angle differences of up to 1 degree, up to 2 degrees, up to 4 degrees, up to 6 degrees, up to 8 degrees, up to 10 degrees, up to 12 degrees, up to 14 degrees, up to 16 degrees, and / or up to 18 degrees.

[0117] When the determination at 350 involves applying a spoofed parameter in the form of a linear acceleration component, the determination at 350 may include determining that a recoil condition exists if or only if the linear acceleration component is outside the range of a threshold linear acceleration component. In other words, during normal operation of the circular saw cutting the workpiece, the linear acceleration component can be within the range of the threshold linear acceleration component. However, during or before a recoil condition, the linear acceleration component may differ from the range of the threshold linear acceleration component. Again, in other words, when a false recoil is detected during normal operation of the circular saw cutting the workpiece, the linear acceleration component can be within the range of the threshold linear acceleration component. Method 300 is configured not to initiate a response at 360 during such a false recoil condition. Therefore, the linear acceleration component being outside the range of the threshold linear acceleration can be a necessary condition for determining the existence of a recoil condition. In other words, the linear acceleration component being within the range of the threshold linear acceleration component is a necessary condition for determining the existence of a false recoil condition and / or the absence of a recoil condition.

[0118] When the linear acceleration component is outside the threshold linear acceleration component range, the direction of the linear acceleration component can be towards the trailing edge of the circular saw. Alternatively, when the linear acceleration component is within the threshold linear acceleration component range, the direction of the linear acceleration component can be towards the leading edge of the circular saw.

[0119] The threshold linear acceleration component range can include and / or can be any suitable linear acceleration component value. Figure 16 In the coordinate system shown, positive acceleration values ​​generally point towards the trailing edge 28 and negative acceleration values ​​generally point towards the leading edge 24. Linear acceleration components within the threshold linear acceleration component range can have a negative sign (i.e., they can point towards the leading edge 24). In such a coordinate system, the upper limit of the linear acceleration component values ​​within the threshold linear acceleration component range is 237 (e.g., ...). Figure 20 (As shown) includes up to -1.5 meters per square second (m / s) 2 (At most -2m / s) 2 At most -2.5m / s 2 At most -3m / s 2 At most -3.5m / s 2 At most -4m / s 2 At most -4.5m / s 2 Maximum -5m / s 2 Maximum -5.5m / s 2 Maximum -6m / s 2 At least -10m / s 2 At least -9.5m / s 2 At least -9m / s 2 At least -8.5m / s 2 At least -8m / s 2 At least -7.5m / s 2 At least -7m / s 2 At least -6.5m / s 2 At least -6m / s 2 At least -5.5m / s 2 At least -5m / s 2 At least -4.5m / s 2 and / or at least -4 m / s 2 The linear acceleration value.

[0120] Another example of falsified parameters includes the linear acceleration direction component of the circular saw's acceleration, which can be determined, for example, during detection at 330. The linear acceleration direction component can point in a specific, defined, and / or predetermined linear acceleration direction. In other words, the linear acceleration direction component can be a specific subset of the overall acceleration direction of the circular saw, where that specific subset points in the linear acceleration direction.

[0121] The linear acceleration direction component may include or be equivalent to any suitable specific, defined, and / or predetermined linear acceleration direction. As an example, the linear acceleration direction component may be towards the leading edge of the circular saw or away from the user of the saw. In other words, such a linear acceleration direction component may be away from the user-actuated side of the workpiece support, such as... Figure 16 As shown in 222. In such a coordinate system, the linear acceleration direction component values ​​within the threshold linear acceleration direction component range include linear acceleration direction values ​​of up to 80 degrees (°), up to 60°, up to 45°, at least -80°, at least -60°, at least -45°, at least -30° and / or at least 0°.

[0122] Another example of falsified parameters includes the angular velocity component of the circular saw's angular velocity measured about an angular velocity axis. The angular velocity axis may include and / or may be an axis along which the linear acceleration direction extends, and may also be referred to herein as the linear acceleration axis. In other words, the angular velocity axis may coincide with the linear acceleration direction. In other words, the angular velocity component may include and / or may be a specific subset of the total angular velocity of the circular saw measured about the angular velocity axis. Examples of angular velocity components are... Figure 21 It is shown in the figure and discussed in more detail in this article.

[0123] When the determination at 350° involves applying a spoofed parameter in the form of an angular velocity component, the determination at 350° may include determining that a recoil condition exists when or only when the angular velocity component is outside the threshold angular velocity component range. In other words, during normal operation of a circular saw cutting a workpiece, the angular velocity component can be within the threshold angular velocity component range. However, during or before a recoil condition, the angular velocity component may differ from the threshold angular velocity component range. Additionally or alternatively, the angular velocity component can be within the threshold angular velocity component range when a recoil condition does not exist and / or when a false recoil is detected during normal operation of a circular saw cutting a workpiece. Therefore, the angular velocity component being outside the threshold angular velocity component range can be a necessary condition for determining the existence of a recoil condition. In other words, the angular velocity component being within the threshold angular velocity component range is a necessary condition for determining the existence of a false recoil condition.

[0124] When the angular velocity component is within the threshold angular velocity component range, rotation about the angular velocity axis and / or about the cutting direction includes the rotation of the circular saw mandrel and / or the circular saw blade toward the workpiece. Alternatively, when the linear acceleration component is outside the threshold angular velocity component range, rotation about the angular velocity axis and / or about the cutting direction includes the rotation of the circular saw mandrel and / or the circular saw blade away from the workpiece.

[0125] The threshold angular velocity component range can include any suitable angular velocity component value. Figure 16In the coordinate system shown, positive acceleration values ​​generally point towards the trailing edge 28 and negative acceleration values ​​generally point towards the leading edge 24. Angular velocity components within the threshold angular velocity component range can have a negative sign for rotations following the right-hand rule. In such a coordinate system, the upper limit of the angular velocity component values ​​within the threshold angular velocity component range is 239 (e.g., ...). Figure 21 (As shown) includes speeds of up to -1.5 degrees per second (° / s), up to -2° / s, up to -2.5° / s, up to -3° / s, up to -3.5° / s, up to -4° / s, up to -4.5° / s, up to -5° / s, up to -5.5° / s, up to -6° / s, up to -6.5° / s, up to -7° / s, up to -7.5° / s, up to -8° / s, at least -12° / s, at least -1 Angular velocities of 1.5° / s, at least -11° / s, at least -10.5° / s, at least -10° / s, at least -9.5° / s, at least -9° / s, at least -8.5° / s, at least -8° / s, at least -7.5° / s, at least -7° / s, at least -6.5° / s, at least -6° / s, at least -5.5° / s, at least -5° / s, at least -4.5° / s, and / or at least -4° / s.

[0126] In some examples, spoofed parameters, such as linear acceleration components and / or angular velocity components, can be determined and / or detected within a detection time window. When used, the detection time window can extend the threshold detection time prior to the recoil time of the handheld power tool. The recoil time can include and / or may be the time during which the magnitude of the handheld power tool's acceleration is greater than a threshold acceleration value, the direction of the handheld power tool's acceleration is within a threshold direction range, and / or the angular velocity of the handheld power tool is greater than a threshold angular velocity value. The detection time window may have a duration, which can be defined by the threshold detection time prior to the recoil time. Examples of durations include at least 20 milliseconds (ms), at least 30 ms, at least 40 ms, at least 50 ms, at least 60 ms, at least 70 ms, at least 80 ms, at least 90 ms, at least 100 ms, at least 110 ms, at least 120 ms, at least 130 ms, at least 140 ms, up to 220 ms, up to 210 ms, up to 200 ms, up to 190 ms, up to 180 ms, up to 170 ms, up to 160 ms, up to 150 ms, up to 140 ms, up to 130 ms, up to 120 ms, up to 110 ms, and / or up to 100 ms.

[0127] As discussed, falsified parameters can be utilized or applied based on the configuration of the handheld power tool or circular saw. Examples of falsified parameters determined using a handheld circular saw are provided below. Figure 20 and Figure 21 As shown in the image. Figure 20 The simulated parameters in the form of linear acceleration components of a handheld circular saw are shown, while Figure 21 The falsified parameters in the form of the angular velocity component of a handheld circular saw are shown.

[0128] Figure 20 and Figure 21 The forged parameters are shown (i.e., Figure 20 linear acceleration components and Figure 21 For example, spoofing parameters (of the angular velocity component) can be used to distinguish between actual and false recoil indications at recoil time 220°, as discussed herein. Figure 20 and Figure 21 In this context, the recoil time (i.e., the initiation of the recoil state, indicated by the circular saw's acceleration magnitude exceeding a threshold acceleration value, the circular saw's acceleration direction being within the threshold direction range, and the circular saw's angular velocity exceeding a threshold angular velocity value) is indicated at 220°. However, as discussed in more detail herein, handheld circular saws do not always experience recoil at recoil time 220°. Figure 20 and Figure 21 In the diagram, an example of normal operation (i.e., no backlash) of a handheld circular saw during chop cut is indicated by line 230, while two examples of actual backlash in a handheld circular saw are indicated by line 232. Similarly, in... Figure 20 and Figure 21 The detection time window is indicated at position 234.

[0129] exist Figure 20 In this context, negative linear acceleration components point away from the user's direction of the handheld circular saw and / or in the cutting direction (e.g., towards the leading edge of the circular saw), while positive linear acceleration components point towards the user of the handheld circular saw and / or opposite to the cutting direction (e.g., towards the trailing edge of the handheld circular saw). Figure 20 As shown, and during normal operation of the handheld circular saw (as shown at 230), at least during a subset of the detection time window 234, the linear acceleration component is within the threshold linear acceleration component range 236. However, also as... Figure 20 As shown, when recoil occurs from the handheld circular saw (as indicated at 232), the linear acceleration component is outside the threshold linear acceleration component range 236 throughout the entire detection time window. Therefore, the linear acceleration component can indicate or be used to detect true and / or false recoil from the handheld circular saw.

[0130] exist Figure 21 In this context, a negative angular velocity value causes the spindle of the handheld circular saw to rotate towards the workpiece (i.e., when viewed in the cutting direction, the circular saw or its user-actuated component rotates clockwise), while a positive angular velocity value causes the spindle of the handheld circular saw to rotate away from the workpiece (i.e., when viewed in the cutting direction, the circular saw or its user-actuated component rotates counterclockwise). For example... Figure 21 As shown, and during the normal operation of the handheld circular saw performing splitting (as shown at 230), the angular velocity component is within the threshold angular velocity component range 238 for at least a subset of the detection time window 234. However, also as... Figure 21 As shown, and during the recoil of the circular saw (as indicated at 232), the angular velocity component is outside the threshold angular velocity component range 238 throughout the entire detection time window. Therefore, the angular velocity component can indicate or be used to detect real and / or false recoil of a handheld circular saw.

[0131] The response to the presence of recoil at 360° can include responding in any suitable manner. As an example, the response at 360° can include interrupting rotation at 310°. In some such examples, interrupting rotation can include interrupting the current supply to the circular saw's motor. In some such examples, the circular saw can include a brake assembly that can be configured to be selectively actuated to interrupt rotation of the circular saw blades, such as... Figure 1 and Figure 2 The brake assembly 80; additionally or alternatively, interrupting rotation may include actuating the brake assembly to interrupt the rotation of the circular saw blade.

[0132] In some examples, method 300 may include initiating a response at 360 in response to, or only in response to, a determination at 350. In other words, a given recoil event may occur during multiple discrete time intervals of the determination at 350, and the response at 360 may include responding when or only when the determination at 350 indicates that a recoil condition exists during two or more discrete periods of the discrete multiple events.

[0133] As discussed, aspects of the handheld power tool 8 according to this disclosure are discussed more specifically in the case of the circular saw 10. Similarly, aspects of the method 300 according to this disclosure are also discussed more specifically in the case of the circular saw. This discussion is for illustrative purposes only, and within the scope of this disclosure, method 300 can be used with other types of handheld power tools, such as those discussed herein. In this regard, the circular saw disclosed herein with reference to method 300 may also be referred to herein as a handheld power tool and / or may be a handheld power tool. Similarly, the blade disclosed herein with reference to method 300 may also be referred to herein as an instrument and / or may be an instrument. Additionally, the spindle disclosed herein with reference to method 300 may also be referred to herein as an instrument holder and / or may be an instrument holder. Furthermore, the blade rotation plane disclosed herein with reference to method 300 may also be referred to herein as and / or may be an instrument movement plane and / or an instrument movement axis.

[0134] In this disclosure, several illustrative, non-exclusive examples have been discussed and / or presented in the context of flowcharts or schematic diagrams, wherein methods are shown and described as a series of boxes or steps. Unless specifically set forth in the accompanying description, within the scope of this disclosure, the order of boxes may differ from the order shown in the flowcharts, including two or more boxes (or steps) occurring in a different order and / or simultaneously. Also within the scope of this disclosure, these boxes or steps may be implemented as logic, and this can also be described as implementing these boxes or steps as logic. In some applications, a box or step may represent a statement and / or action to be performed by a functionally equivalent circuit or other logic device. The boxes shown may, but are not required to, represent executable instructions that cause a computer, processor, and / or other logic device to respond, perform actions, change state, generate output or display, and / or make decisions.

[0135] As used herein, the word “and / or” between the first entity and the second entity refers to one of the following: (1) the first entity, (2) the second entity, and (3) the first entity and the second entity. Multiple entities listed with “and / or” should be interpreted in the same way, i.e., “one or more” of the entities so connected. In addition to the entities specifically identified by the “and / or” clause, there may optionally be other entities related to or unrelated to those specifically identified. Thus, as a non-limiting example, in one implementation, when used in conjunction with open-ended language such as “including,” a reference to “A and / or B” may refer only to A (optionally including entities other than B); in another implementation, only to B (optionally including entities other than A); and in yet another implementation, to both A and B (optionally including other entities). These entities may refer to elements, actions, structures, steps, operations, values, etc.

[0136] As used herein, the phrase "at least one" in relation to a list of one or more entities should be understood to mean at least one entity selected from any one or more entities in the list of entities, but not necessarily at least one of every entity specifically listed in the list of entities, and does not exclude any combination of entities in the list of entities. This limitation also allows for the optional presence of entities other than those specifically identified within the list of entities referred to by the phrase "at least one," which may be related to or unrelated to those specifically identified entities. Thus, as a non-limiting example, "at least one of A and B" (or equivalently, "at least one of A or B," or equivalently, "at least one of A and / or B") may in one embodiment mean at least one A, optionally including more than one A, without B (and optionally including entities other than B); in another embodiment, mean at least one B, optionally including more than one B, without A (and optionally including entities other than A); and in yet another embodiment, mean at least one A (optionally including more than one A) and at least one B (optionally including more than one B) (and optionally including other entities). In other words, the phrases “at least one,” “one or more,” and “and / or” are open-ended expressions that are both conjunction and disjunctive in operation. For example, each of the expressions “at least one of A, B, and C,” “at least one of A, B, or C,” “one or more of A, B, and C,” “one or more of A, B, or C,” and “A, B, and / or C” can refer to a single A, a single B, a single C, A and B together, A and C together, B and C together, A, B, and C together, and optionally any of the above combined with at least one other entity.

[0137] If any patent, patent application or other reference is incorporated herein by reference and (1) defines a term in a manner inconsistent with the non-incorporated portion of this disclosure or any other incorporated reference and / or (2) otherwise is inconsistent with the non-incorporated portion of this disclosure or any other incorporated reference, the non-incorporated portion of this disclosure shall be controlled, and the term or incorporated disclosure thereof shall be controlled only relative to the reference defining the term and / or the original reference in which the incorporated disclosure is located.

[0138] As used herein, the terms “suitable” and “configured” mean that an element, component, or other object is designed and / or intended to perform a given function. Therefore, the use of the terms “suitable” and “configured” should not be construed as meaning that a given element, component, or other object is simply “capable” of performing a given function, but rather that the element, component, and / or other object is specifically selected, created, implemented, utilized, programmed, and / or designed for the purpose of performing that function. Also within the scope of this disclosure, elements, components, and / or other listed objects enumerated as suitable for performing a particular function may additionally or alternatively be described as being configured to perform that function, and vice versa.

[0139] As used herein, the phrases “for example,” “as an example,” and / or simply the term “example,” when used with reference to one or more components, features, details, structures, embodiments, and / or methods according to this disclosure, are intended to convey illustrative, non-exclusive examples of the described components, features, details, structures, embodiments, and / or methods according to this disclosure. Therefore, the described components, features, details, structures, embodiments, and / or methods are not intended to be limiting, essential, or exclusive / exhaustive; and other components, features, details, structures, embodiments, and / or methods (including structurally and / or functionally similar and / or equivalent components, features, details, structures, embodiments, and / or methods) are also within the scope of this disclosure.

[0140] As used herein, when modifying degree or relation, "at least substantially" may include not only the listed "substantially" degree or relation, but also the entire range of the listed degree or relation. The substantially quantity of the listed degree or relation may include at least 75% of the listed degree or relation. For example, an object at least substantially formed of a certain material includes an object in which at least 75% of the object is formed of that material, and also includes an object formed entirely of that material. As another example, a first length at least substantially equal to a second length includes a first length within 75% of the second length, and also includes a first length equal to the second length.

[0141] Illustrative, non-exclusive examples of circular saws and methods according to this disclosure are presented in the following enumerated paragraphs. Within the scope of this disclosure, each step of the methods listed herein, including in the following enumerated paragraphs, may additionally or alternatively be referred to as a "step" for performing the enumerated actions.

[0142] A1. A circular saw, comprising:

[0143] The user-actuated component includes at least one of the following components:

[0144] (i) A motion sensor configured to detect the motion of a user-actuated component and generate a motion signal indicating the motion of the user-actuated component;

[0145] (ii) A controller programmed to control the operation of the circular saw based at least in part on motion signals;

[0146] (iii) Optionally, a gripping area is configured to be gripped by the user of the circular saw during operation of the circular saw cutting a workpiece;

[0147] (iv) Optionally, a switch is configured to be selectively actuated by a user to selectively apply current to at least one other component of the circular saw;

[0148] (v) Optionally, a motor includes a motor shaft configured to rotate about a rotation axis;

[0149] (vi) Optionally, a spindle, operably attached to a motor shaft and configured to receive a circular saw blade; and

[0150] (vii) Optionally, the circular saw blade, wherein the circular saw blade is operably attached to the circular saw via a spindle;

[0151] A workpiece support is configured to position the workpiece and the circular saw relative to each other when the circular saw cuts the workpiece. Optionally, the workpiece support defines a component-facing side facing the user actuation assembly and a component-opposite side facing away from the user actuation assembly.

[0152] A pivot, wherein the user actuation assembly is pivotally coupled to the workpiece support via the pivot, and further wherein the user actuation assembly and the workpiece support are configured to be operably rotated relative to each other about the pivot axis of the pivot, optionally selectively altering the area of ​​the circular saw blade extending on the opposite side of the assembly of the workpiece support.

[0153] A2. According to the circular saw in paragraph A1, the motion sensor includes or is a microelectromechanical system (MEMS) motion sensor.

[0154] A3. A circular saw based on either paragraph A1 or A2, wherein the motion sensor is configured to perform at least one of the following:

[0155] (i) Detect acceleration along a single detection axis;

[0156] (ii) Detect acceleration along two perpendicular detection axes;

[0157] (iii) Detect acceleration along three orthogonal detection axes;

[0158] (iv) Detect rotation about a single detection axis;

[0159] (v) Detecting rotation about two perpendicular detection axes; and

[0160] (vi) Detect rotation around three orthogonal detection axes.

[0161] A4. A circular saw based on any one of paragraphs A1 to A3, wherein a motion sensor is configured to detect acceleration in an acceleration detection plane, the acceleration detection plane being at least one of the following:

[0162] (i) Perpendicular to the axis of rotation;

[0163] (ii) Perpendicular to the pivot axis; and

[0164] (iii) Parallel to the plane of rotation of the circular saw blade as it rotates during circular sawing.

[0165] A5. A circular saw according to any one of paragraphs A1 to A4, wherein a motion sensor is configured to detect rotation about a detection axis, the detection axis extending in at least one of the following ways:

[0166] (i) Perpendicular to the axis of rotation;

[0167] (ii) Perpendicular to the pivot axis;

[0168] (iii) The plane of rotation of the circular saw blade parallel to the plane in which the circular saw blade rotates during operation; and

[0169] (iv) Parallel to one of the acceleration detection planes.

[0170] A6. A circular saw based on any of paragraphs A1 to A5, wherein the motion sensor is positioned at a threshold pivot axis-sensor distance from the pivot axis, optionally wherein the threshold pivot axis-sensor distance is at least one of the following distances:

[0171] (i) at least 1 cm, at least 2 cm, at least 3 cm, at least 4 cm, at least 5 cm, at least 6 cm, at least 7 cm, or at least 8 cm; and

[0172] (ii) up to 20cm, up to 18cm, up to 16cm, up to 14cm, up to 12cm, up to 10cm, up to 9cm, up to 8cm, up to 7cm, up to 6cm, up to 5cm, up to 4cm, up to 3cm, up to 2cm or up to 1cm.

[0173] A7. A circular saw based on any of paragraphs A1 to A6, wherein a motion sensor is configured to detect acceleration along an acceleration detection axis.

[0174] A8. According to the circular saw in paragraph A7, the acceleration detection axis extends perpendicular to or at least substantially perpendicular to the pivot axis.

[0175] A9. Based on the circular saw in either paragraph A7 or A8, where the acceleration detection axis extends from the pivot axis to the threshold pivot axis-acceleration axis distance, optionally, where the threshold pivot axis-acceleration axis distance is at least one of the following distances:

[0176] (i) at least 1 millimeter (mm), at least 2 mm, at least 3 mm, at least 4 mm, at least 5 mm, at least 6 mm, at least 7 mm, at least 8 mm, at least 9 mm, or at least 1 cm; and

[0177] (ii) up to 4cm, up to 3cm, up to 2cm, up to 1cm, up to 8mm, up to 6mm, up to 4mm, up to 2mm or up to 1mm.

[0178] A10. Based on any of paragraphs A7 to A9, a circular saw is used where the acceleration detection axis extends through the pivot axis.

[0179] A11. A circular saw based on any of paragraphs A7 to A10, wherein the acceleration detection axis extends radially relative to the axis of rotation.

[0180] A12. A circular saw according to any of paragraphs A1 to A11, wherein the user-actuated component includes a circuit board that includes both a controller and a motion sensor.

[0181] A13. A circular saw according to any of paragraphs A1 to A12, wherein the circular saw further includes a biasing mechanism configured to bias the user actuation component away from the workpiece support.

[0182] A14. A circular saw according to any of paragraphs A1 to A13, wherein the circular saw further includes an insert lock configured to be selectively deactivated by the user to selectively allow the user actuation assembly to pivot about a pivot axis and toward a workpiece support.

[0183] A15. A circular saw according to any one of paragraphs A1 to A14, wherein the circular saw defines a front region and a rear region, the front region being configured to initiate contact with the workpiece when the circular saw cuts the workpiece, and the rear region being configured to follow the front region of the workpiece when the circular saw cuts the workpiece.

[0184] A16. According to the circular saw in paragraph A15, the pivot axis is at least one of the following:

[0185] (i) extending into the front area; and

[0186] (ii) Extends into the rear region.

[0187] A17. A circular saw based on either paragraph A15 or A16, wherein the motion sensor is located at at least one of the following positions:

[0188] (i) positioned within the front area; and

[0189] (ii) Positioned in the rear area.

[0190] A18. A circular saw according to any one of paragraphs A15 to A17, wherein a front region defines a leading edge, a rear region defines a trailing edge, and further wherein the pivot axis lies within a threshold edge distance of one of the leading and trailing edges, optionally wherein the threshold edge distance is at least one of the following distances:

[0191] (i) at least 1 mm, at least 5 mm, at least 1 cm, at least 2 cm, or at least 4 cm; and

[0192] (ii) up to 10cm, up to 8cm, up to 6cm or up to 4cm.

[0193] A19. A circular saw according to any one of paragraphs A1 to A18, wherein the controller is programmed to determine a motion signal indicating a recoil condition of the circular saw, and further wherein the controller is programmed to interrupt the rotation of the circular saw blade in response to the determination that a recoil condition exists.

[0194] A20. A circular saw according to paragraph A19, wherein the circular saw further includes a brake assembly configured to be selectively actuated to interrupt the rotation of the circular saw blade, and further wherein the controller is programmed to actuate the brake assembly in response to a recoil condition.

[0195] A21. Based on the circular saw in either paragraph A19 or A20, wherein the controller is programmed to determine a recoil condition when the acceleration axis of the acceleration detected by the motion sensor extends through the pivot axis.

[0196] A22. A circular saw based on any of paragraphs A19 to A21, wherein the controller is programmed to interrupt the supply of current to the motor in response to determining that a backlash condition exists.

[0197] A23. A circular saw based on any of paragraphs A1 to A22, wherein the controller is programmed to perform any appropriate step of any method from any of paragraphs B1 to B40.

[0198] A24. A circular saw according to any one of paragraphs A1 to A23, wherein the circular saw includes at least one of the following:

[0199] (i) a handheld circular saw; and

[0200] (ii) Semi-fixed circular saw.

[0201] A25. A circular saw according to any one of paragraphs A1 to A24, wherein the circular saw includes at least one of the following types of saws:

[0202] (i) Cutting saw;

[0203] (ii) Bevel saw;

[0204] (iii) Rail saw;

[0205] (iv) Radial saw;

[0206] (v) to cut or saw;

[0207] (vi) a panel saw; and

[0208] (vii) Bevel saw.

[0209] B1. A method for detecting the recoil condition of a circular saw including a circular saw blade, the method comprising:

[0210] To make the circular saw blade rotate within the plane of blade rotation; and

[0211] The movement of the circular saw is detected, optionally including at least one of the following:

[0212] (i) Detecting the magnitude of the circular saw's acceleration, optionally within an acceleration detection plane, which is at least one of being parallel to the blade's rotation plane and co-existing with the blade's rotation plane;

[0213] (ii) Detecting the direction of acceleration of the circular saw, optionally within the acceleration detection plane; and

[0214] (iii) Detecting the angular velocity of the circular saw, optionally about at least one rotational detection axis extending in the acceleration detection plane; and

[0215] The presence of recoil is determined at least in part based on verification parameters including the motion of the circular saw, optionally wherein the determination includes determining the presence of recoil when or only when at least one of the following occurs:

[0216] (i) The magnitude of the circular saw's acceleration is greater than the acceleration threshold;

[0217] (ii) The direction of the circular saw's acceleration is within the threshold direction range; and

[0218] (iii) The angular velocity of the circular saw is greater than the threshold angular velocity value.

[0219] B2. According to the method in paragraph B1, the detection further includes detecting workpiece contact parameters, wherein when the circular saw blade is in contact with the workpiece, the workpiece contact parameters are within the contact value range, wherein when the circular saw blade is spaced apart from the workpiece, the workpiece contact parameters are within the non-contact value range, and further wherein the verification parameters further include the workpiece contact parameters and / or wherein the method includes determining that a backlash condition exists when or only when the workpiece contact parameters are within the contact value range.

[0220] B3. According to the method in paragraph B2, wherein the workpiece contact parameters include the angular velocity of the circular saw blade during rotation, wherein the circular saw blade defines a mean free angular velocity when it is spaced from the workpiece, and further wherein the contact value range includes angular velocities below a threshold angular velocity reduction, optionally wherein the threshold angular velocity reduction is at least 20 revolutions per minute (RPM), at least 25 RPM, at least 30 RPM, at least 35 RPM, at least 40 RPM, at least 50 RPM, at least 60 RPM, at least 70 RPM, at least 80 RPM, at least 90 RPM, at least 100 RPM, at least 150 RPM, at least 200 RPM, at least 300 RPM, at least 400 RPM, at least 500 RPM, at least 600 RPM, at least 700 RPM, or at least 800 RPM.

[0221] B4. According to the method in paragraph B3, detecting the angular velocity of the circular saw blade includes measuring the angular velocity of the circular saw blade.

[0222] B5. The method described in either paragraph B3 or B4, wherein detecting the angular velocity of the circular saw blade includes calculating the angular velocity of the circular saw blade based at least in part on a motor model of the circular saw's motor.

[0223] B6. According to the method in paragraph B5, the calculation of the angular velocity of the circular saw blade also includes calculating the angular velocity of the circular saw blade based at least in part on the magnitude of the current supplied to the motor and the magnitude of the voltage of the current.

[0224] B7. The method according to any one of paragraphs B2 to B6, wherein the workpiece contact parameters include the power consumption of the circular saw during rotation, wherein the motor of the circular saw is limited to a maximum rated power consumption, and further wherein the contact value range includes power consumption greater than a threshold percentage of the maximum rated power consumption, optionally wherein the threshold percentage of the maximum rated power consumption is 50%, 60%, 70%, 80%, or 90%.

[0225] B8. The method according to any one of paragraphs B2 to B7, wherein the circular saw includes a contact detector configured to detect contact between the circular saw blade and the workpiece, and further wherein the contact detector is configured to generate workpiece contact parameters.

[0226] B9. The method according to paragraph B8, wherein the contact detector comprises at least one of the following detectors:

[0227] (i) Electrical contact detector;

[0228] (ii) Capacitive contact detector;

[0229] (iii) Electromagnetic contact detector; and

[0230] (iv) Mechanical contact detector.

[0231] B10. The method according to any one of paragraphs B1 to B9, wherein detecting the magnitude of acceleration includes detecting a first acceleration component in a first direction within the acceleration detection plane, and detecting a second acceleration component in a second direction within the acceleration detection plane and perpendicular to the first direction, wherein the magnitude of acceleration is determined based on the first acceleration component and the second acceleration component.

[0232] B11. The method according to any one of paragraphs B1 to B10, wherein detecting the acceleration direction includes detecting a first acceleration component in the acceleration detection plane in the first direction and detecting a second acceleration component in the acceleration detection plane in the second direction and perpendicular to the first direction, wherein the acceleration direction is the direction of the vector sum of the first and second acceleration components.

[0233] B12. The method according to any one of paragraphs B1 to B11, wherein detecting the angular velocity of the circular saw includes detecting a first angular velocity component surrounding one of the first directions in the acceleration detection plane, and detecting a second angular velocity component surrounding the acceleration detection plane and perpendicular to the first direction, wherein the angular velocity of the circular saw is the vector sum of the first angular velocity component and the second angular velocity component.

[0234] B13. Based on the method in any of paragraphs B1 to B12, the threshold acceleration value is at least 1 meter per square second (m / s²). 2 ), at least 2m / s 2 At least 3m / s 2 At least 4m / s 2 At least 6m / s 2 At least 8m / s 2 At least 10m / s 2 At least 12m / s 2 At least 14 m / s 2 At least 16m / s 2 At least 18m / s 2 or at least 20 m / s 2 .

[0235] B14. The method according to any one of paragraphs B1 to B13, wherein the threshold direction range is at least one of the following:

[0236] (i) pointing backwards relative to the cutting direction of the circular saw; and

[0237] (ii) Point away from the workpiece being cut with a circular saw.

[0238] B15. The method according to any one of paragraphs B1 to B14, wherein the threshold direction range is within a threshold angle range of one / the cutting direction of the circular saw, optionally wherein the threshold angle range is away from the user-actuated component facing side of the workpiece, and is at least one of the following degrees:

[0239] (i) at least 80 degrees, at least 90 degrees, at least 100 degrees, at least 110 degrees, at least 120 degrees, at least 130 degrees, at least 140 degrees, at least 150 degrees, or at least 160 degrees; and

[0240] (ii) up to 180 degrees, up to 170 degrees, up to 160 degrees, up to 150 degrees, up to 140 degrees, up to 130 degrees, up to 120 degrees, up to 110 degrees or up to 100 degrees.

[0241] B16. The method according to any one of paragraphs B1 to B15, wherein the circular saw includes a workpiece support defining a workpiece facing side, a workpiece opposite side, a leading edge, and a trailing edge, and further includes at least one of the following:

[0242] (i) The threshold direction range is at least partially perpendicular to the opposite side of the workpiece support;

[0243] (ii) The threshold direction range is at least partially oriented toward the trailing edge of the workpiece support; and

[0244] (iii) The threshold direction range is limited to a quadrant that extends between a first vector and a second vector, the first vector pointing to the rear edge of the workpiece support and along the opposite side of the workpiece support, and the second vector intersecting the first vector and pointing perpendicular to the opposite side of the workpiece support.

[0245] B17. The method according to any one of paragraphs B1 to B16, wherein the threshold angular velocity value is at least 1 degree per second (° / s), at least 2° / s, at least 3° / s, at least 4° / s, at least 6° / s, at least 8° / s, or at least 10° / s.

[0246] B18. According to the method of any of paragraphs B1 to B17, wherein the threshold angular velocity range includes the angular velocity that causes the blade of the circular saw's workpiece support to move away from the workpiece.

[0247] B19. The method according to any one of paragraphs B1 to B18, wherein, after initiating rotation and simultaneously with detection, the method further includes cutting the workpiece with a circular saw blade.

[0248] B20. The method according to any one of paragraphs B1 to B19, wherein the method further includes responding to determining that a recoil condition exists.

[0249] B21. According to the method in paragraph B20, the response includes interrupting the rotation.

[0250] B22. The method according to either paragraph B20 or B21, wherein the circular saw includes a brake assembly configured to be selectively actuated to interrupt rotation of the circular saw blade, and further wherein the response includes actuating the brake assembly to interrupt rotation of the circular saw blade.

[0251] B23. The method according to any of paragraphs B20 to B22, wherein the response includes interrupting the supply of current to the motor of the circular saw.

[0252] B24. The method according to any one of paragraphs B20 to B23, wherein the method includes initiating a response in response to determining that a recoil condition exists.

[0253] B25. The method according to any one of paragraphs B1 to B24, wherein the method further includes applying a falsified parameter, further wherein the determination is at least partially based on the falsified parameter, and optionally wherein the circular saw includes at least one of a handheld circular saw, a miter saw, and a cleaving saw.

[0254] B26. According to the method in paragraph B25, the forged parameters include a linear acceleration component of the circular saw's acceleration, wherein the linear acceleration component is in a linear acceleration direction, which is at least one of the following:

[0255] (i) The component facing side of the workpiece support that is parallel to or at least substantially parallel to the blade rotation plane of the circular saw blade and parallel to or at least substantially parallel to the circular saw; and

[0256] (ii) Parallel to or at least substantially parallel to the longitudinal axis of the groove defined by the circular saw blade within the workpiece.

[0257] B27. According to the method in paragraph B26, determining includes determining the existence of recoil when or only when the linear acceleration component is outside the threshold linear acceleration component range, or determining the absence of recoil when the linear acceleration component is within the threshold linear acceleration component range, optionally, wherein the threshold linear acceleration component range is defined by linear acceleration component values ​​having at least one of the following values:

[0258] (i) at most -1.5 m / s² 2 (At most -2m / s) 2 At most -2.5m / s 2 At most -3m / s 2 At most -3.5m / s 2 At most -4m / s 2 At most -4.5m / s 2 At most -5m / s 2 At most -5.5m / s 2 Or at most -6m / s 2 ;as well as

[0259] (ii) at least -10m / s 2 At least -9.5m / s 2 At least -9m / s 2 At least -8.5m / s 2 At least -8m / s 2 At least -7.5m / s 2 At least -7m / s 2 At least -6.5m / s 2 At least -6m / s 2 At least -5.5m / s 2 At least -5m / s 2 At least -4.5m / s 2 Or at least -4m / s 2 .

[0260] B28. According to the method in paragraph B27, when the linear acceleration component is within the range of the threshold linear acceleration component, the direction of the linear acceleration component points towards the leading edge of the circular saw.

[0261] B29. According to the method of any of paragraphs B26 to B28, wherein the direction of linear acceleration extends along the linear acceleration axis, wherein the forged parameters include the angular velocity component of the circular saw's angular velocity, and further wherein the angular velocity component is about the linear acceleration axis.

[0262] B30. According to the method in paragraph B29, determining includes determining that recoil exists when or only when the angular velocity component is outside the threshold angular velocity component range, or determining that recoil does not exist when the angular velocity component is within the threshold angular velocity component range, optionally, wherein the threshold angular velocity component range is defined by angular velocity values ​​that are at least one of the following:

[0263] (i) at most -1.5 degrees per second (° / s), at most -2° / s, at most -2.5° / s, at most -3° / s, at most -3.5° / s, at most -4° / s, at most -4.5° / s, at most -5° / s, at most -5.5° / s, at most -6° / s, at most -6.5° / s, at most -7° / s, at most -7.5° / s, or at most -8° / s; and

[0264] (ii) at least -12° / s, at least -11.5° / s, at least -11° / s, at least -10.5° / s, at least -10° / s, at least -9.5° / s, at least -9° / s, at least -8.5° / s, at least -8° / s, at least -7.5° / s, at least -7° / s, at least -6.5° / s, at least -6° / s, at least -5.5° / s, at least -5° / s, at least -4.5° / s, or at least -4° / s.

[0265] B31. According to the method in paragraph B30, the angular velocity component is within the threshold angular velocity component range when or only when the rotation about the linear acceleration axis includes the rotation of the circular saw's mandrel toward the workpiece support of the circular saw.

[0266] B32. The method described in any of paragraphs B25 to B31, where the forgery parameters are determined within the detection time window.

[0267] B33. According to the method in paragraph B32, where the detection time window extends the threshold detection time before the recoil time, at the recoil time, at least one of the following conditions exists:

[0268] (i) The magnitude of the circular saw's acceleration is greater than the threshold acceleration value;

[0269] (ii) The direction of the circular saw's acceleration is within the threshold direction range; and

[0270] (iii) The angular velocity of the circular saw is greater than the threshold angular velocity value.

[0271] B34. According to the method in either paragraph B32 or B33, the detection time window has at least one of the following durations:

[0272] (i) at least 20 milliseconds (ms), at least 30 ms, at least 40 ms, at least 50 ms, at least 60 ms, at least 70 ms, at least 80 ms, at least 90 ms, at least 100 ms, at least 110 ms, at least 120 ms, at least 130 ms, or at least 140 ms; and

[0273] (ii) up to 220ms, up to 210ms, up to 200ms, up to 190ms, up to 180ms, up to 170ms, up to 160ms, up to 150ms, up to 140ms, up to 130ms, up to 120ms, up to 110ms or up to 100ms.

[0274] B35. According to the method in any of paragraphs B25 to B34, where the falsified parameters include the linear acceleration direction component of the circular saw's acceleration.

[0275] B36. According to the method in paragraph B35, the linear acceleration directional component is at least one of the following:

[0276] (i) Pointing to one / the leading edge of the circular saw;

[0277] (ii) The user's orientation away from the circular saw; and

[0278] (iii) The one of the circular saws / the one of the workpiece supports / the one of the user actuation components faces the side.

[0279] B37. According to the method of either paragraph B35 or B36, wherein the linear acceleration direction component is within a threshold angle range of the circular saw's cutting direction, optionally wherein the threshold angle range is defined by at least one of the following degrees:

[0280] (i) at least 0°, at least -30°, at least -45°, at least -60°, or at least -80°; and

[0281] (ii) up to 80°, up to 60° or up to 45°.

[0282] B38. The method according to any one of paragraphs B1 to B37, wherein the circular saw includes at least one of the following circular saws:

[0283] (i) a handheld circular saw; and

[0284] (ii) Semi-fixed circular saw.

[0285] B39. According to the method of any one of paragraphs B1 to B38, wherein the circular saw includes at least one of the following saws:

[0286] (i) Cutting saw;

[0287] (ii) Bevel saw;

[0288] (iii) Rail saw;

[0289] (iv) Radial saw;

[0290] (v) to saw;

[0291] (vi) a panel saw; and

[0292] (vii) Bevel saw.

[0293] B40. According to the method of any of paragraphs B1 to B39, wherein the circular saw includes any suitable structure of any circular saw of any of paragraphs A1 to A25.

[0294] C1. A method for detecting the recoil condition of a handheld power tool, the method comprising:

[0295] To move the handheld power tool within its plane of motion;

[0296] Detecting the movement of a handheld power tool, optionally wherein detecting the movement includes at least one of the following:

[0297] (i) Detecting the magnitude of acceleration of a handheld power tool, optionally within an acceleration detection plane, which is at least one of being parallel to the tool's motion plane and co-existing with the tool's motion plane;

[0298] (ii) Detecting the acceleration direction of the handheld power tool, optionally within the acceleration detection plane; and

[0299] (iii) Detecting the angular velocity of a handheld power tool, optionally about at least one rotational detection axis extending in the acceleration detection plane; and

[0300] The presence of recoil is determined at least in part based on verification parameters including the movement of a handheld power tool. Optionally, the determination includes determining the presence of recoil when or only when at least one of the following occurs:

[0301] (i) The magnitude of the acceleration of the handheld power tool is greater than the threshold acceleration value;

[0302] (ii) The acceleration direction of the handheld power tool is within the threshold direction range; and

[0303] (iii) The angular velocity of the handheld power tool is greater than the threshold angular velocity value.

[0304] C2. According to the method in paragraph C1, the detection further includes detecting workpiece contact parameters, wherein when the instrument is in contact with the workpiece, the workpiece contact parameters are within the contact value range, wherein when the instrument is spaced apart from the workpiece, the workpiece contact parameters are within the non-contact value range, and further wherein the verification parameters further include workpiece contact parameters and / or wherein the method includes determining that a backlash condition exists when or only when the workpiece contact parameters are within the contact value range.

[0305] C3. According to the method in paragraph C2, wherein the workpiece contact parameters include the angular velocity of the instrument during movement, wherein the instrument defines a mean free angular velocity when the instrument is spaced from the workpiece, and further wherein the contact value range includes angular velocities below a threshold angular velocity reduction, optionally wherein the threshold angular velocity reduction is at least 20 revolutions per minute (RPM), at least 25 RPM, at least 30 RPM, at least 35 RPM, at least 40 RPM, at least 50 RPM, at least 60 RPM, at least 70 RPM, at least 80 RPM, at least 90 RPM, at least 100 RPM, at least 150 RPM, at least 200 RPM, at least 300 RPM, at least 400 RPM, at least 500 RPM, at least 600 RPM, at least 700 RPM, or at least 800 RPM.

[0306] C4. According to the method in paragraph C3, the detection of workpiece contact parameters includes the angular velocity of the measuring instrument.

[0307] C5. The method according to either paragraph C3 or C4, wherein detecting workpiece contact parameters includes calculating the angular velocity of the tool based at least in part on a motor model of the motor of the handheld power tool.

[0308] C6. According to the method in paragraph C5, the angular velocity of the calculating device also includes calculating the angular velocity of the device based at least in part on the magnitude of the current supplied to the motor and the magnitude of the voltage of the current.

[0309] C7. The method according to any one of paragraphs C2 to C6, wherein the workpiece contact parameters include the power consumption of the handheld power tool during movement, wherein the motor of the handheld power tool is limited to a maximum rated power consumption, and further wherein the contact value range includes power consumption greater than a threshold percentage of the maximum rated power consumption, optionally wherein the threshold percentage of the maximum rated power consumption is 50%, 60%, 70%, 80%, or 90%.

[0310] C8. The method according to any one of paragraphs C2 to C7, wherein the handheld power tool includes a contact detector configured to detect contact between the tool and the workpiece, and further wherein the contact detector is configured to generate workpiece contact parameters.

[0311] C9. The method according to paragraph C8, wherein the contact detector comprises at least one of the following:

[0312] (i) Electrical contact detector;

[0313] (ii) Capacitive contact detector;

[0314] (iii) Electromagnetic contact detector; and

[0315] (iv) Mechanical contact detector.

[0316] C10. The method according to any one of paragraphs C1 to C9, wherein detecting the magnitude of acceleration includes detecting a first acceleration component in a first direction within the acceleration detection plane, and detecting a second acceleration component in a second direction within the acceleration detection plane and perpendicular to the first direction, wherein the magnitude of acceleration is determined based on the first acceleration component and the second acceleration component.

[0317] C11. The method according to any one of paragraphs C1 to C10, wherein detecting the acceleration direction includes detecting a first acceleration component in the acceleration detection plane in the first direction and detecting a second acceleration component in the acceleration detection plane in the second direction and perpendicular to the first direction, wherein the acceleration direction is the direction of the vector sum of the first and second acceleration components.

[0318] C12. The method according to any one of paragraphs C1 to C11, wherein detecting the angular velocity of the handheld power tool includes detecting a first angular velocity component in one of the first directions within the acceleration detection plane, and detecting a second angular velocity component in one of the second directions within the acceleration detection plane and perpendicular to the first direction, wherein the angular velocity of the handheld power tool is the vector sum of the first and second angular velocity components.

[0319] C13. Based on the method in any of paragraphs C1 to C12, the threshold acceleration value is at least 1 meter per square second (m / s²). 2 ), at least 2m / s 2 At least 3m / s 2 At least 4m / s 2 At least 6m / s 2 At least 8m / s 2 At least 10m / s 2 At least 12m / s 2 At least 14 m / s 2 At least 16m / s 2 At least 18m / s 2 or at least 20 m / s 2 .

[0320] C14. The method according to any one of paragraphs C1 to C13, wherein the threshold direction range is at least one of the following:

[0321] (i) pointing backwards relative to the cutting direction of the handheld power tool; and

[0322] (ii) Keep away from the workpiece being cut using a handheld power tool.

[0323] C15. The method according to any one of paragraphs C1 to C14, wherein the threshold direction range is within a threshold angle range of one / the cutting direction of the handheld power tool, optionally wherein the threshold angle range is away from the workpiece pointing, and is at least one of the following degrees:

[0324] (i) at least 80 degrees, at least 90 degrees, at least 100 degrees, at least 110 degrees, at least 120 degrees, at least 130 degrees, at least 140 degrees, at least 150 degrees, or at least 160 degrees; and

[0325] (ii) up to 180 degrees, up to 170 degrees, up to 160 degrees, up to 150 degrees, up to 140 degrees, up to 130 degrees, up to 120 degrees, up to 110 degrees or up to 100 degrees.

[0326] C16. The method according to any one of paragraphs C1 to C15, wherein the handheld power tool includes a workpiece support defining a workpiece facing side, a workpiece opposite side, a leading edge, and a trailing edge, and further includes at least one of the following:

[0327] (i) The threshold direction range is at least partially perpendicular to the opposite side of the workpiece support;

[0328] (ii) The threshold direction range is at least partially oriented toward the trailing edge of the workpiece support; and

[0329] (iii) The threshold direction range is limited to a quadrant that extends between a first vector and a second vector, the first vector pointing to the trailing edge of the workpiece support and along the opposite side of the workpiece support, and the second vector intersecting the first vector and pointing perpendicular to the opposite side of the workpiece support.

[0330] C17. The method according to any one of paragraphs C1 to C16, wherein the threshold angular velocity value is at least 1 degree per second (° / s), at least 2° / s, at least 3° / s, at least 4° / s, at least 6° / s, at least 8° / s, or at least 10° / s.

[0331] C18. According to the method of any one of paragraphs C1 to C17, wherein the threshold angular velocity value includes the angular velocity that causes the blade of the workpiece support of the handheld power tool to move away from the workpiece.

[0332] C19. The method according to any one of paragraphs C1 to C18, wherein, after initiating movement and simultaneously with detection, the method further includes cutting the workpiece with a tool.

[0333] C20. The method according to any one of paragraphs C1 to C19, wherein the method further includes responding to determining that a recoil condition exists.

[0334] C21. According to the method in paragraph C20, the response includes interrupting movement.

[0335] C22. The method according to any one of paragraphs C20 and C21, wherein the handheld power tool includes a brake assembly configured to be selectively actuated to interrupt the movement of the tool, and further wherein the response includes actuating the brake assembly to interrupt the movement of the tool.

[0336] C23. The method according to any one of paragraphs C20 to C22, wherein the response includes interrupting the supply of current to the motor of the handheld power tool.

[0337] C24. The method according to any one of paragraphs C20 to C23, wherein the method includes initiating a response in response to determining that a recoil condition exists.

[0338] C25. The method according to any one of paragraphs C1 to C24, wherein the method further includes applying falsified parameters, further wherein the determination is at least partially based on the falsified parameters, and optionally wherein the handheld power tool includes at least one of a circular saw, a handheld circular saw, a miter saw, a cleaving saw, a rotary power tool, a rotary handheld power tool, a rotary cutter, a grinder, a polisher, and a drill.

[0339] C26. The method according to paragraph C25, wherein the falsified parameters include a linear acceleration component of the acceleration of the handheld power tool, wherein the linear acceleration component is in a linear acceleration direction, which is at least one of the following:

[0340] (i) The assembly facing side that is parallel to or at least substantially parallel to the tool's plane of motion and parallel to or at least substantially parallel to the workpiece support of the handheld power tool; and

[0341] (ii) Parallel to or at least substantially parallel to the longitudinal axis of the groove defined by the tool within the workpiece.

[0342] C27. According to the method in paragraph C26, determining that recoil condition exists when or only when the linear acceleration component is outside the threshold linear acceleration component range, or determining that recoil condition does not exist when the linear acceleration component is within the threshold linear acceleration component range, optionally, wherein the threshold linear acceleration component range is defined by a linear acceleration component value of at least one of the following:

[0343] (i) at most -1.5 m / s² 2 (At most -2m / s) 2 At most -2.5m / s 2 At most -3m / s 2At most -3.5m / s 2 At most -4m / s 2 At most -4.5m / s 2 At most -5m / s 2 At most -5.5m / s 2 Or at most -6m / s 2 ;as well as

[0344] (ii) at least -10m / s 2 At least -9.5m / s 2 At least -9m / s 2 At least -8.5m / s 2 At least -8m / s 2 At least -7.5m / s 2 At least -7m / s 2 At least -6.5m / s 2 At least -6m / s 2 At least -5.5m / s 2 At least -5m / s 2 At least -4.5m / s 2 Or at least -4m / s 2 .

[0345] C28. According to the method in paragraph C27, when the linear acceleration component is within the range of the threshold linear acceleration component, the direction of the linear acceleration component points towards the leading edge of the handheld power tool.

[0346] C29. According to the method of any of paragraphs C25 to C28, wherein the direction of linear acceleration extends along the linear acceleration axis, wherein the falsified parameters include the angular velocity component of the angular velocity of the handheld power tool, and further wherein the angular velocity component is about the linear acceleration axis.

[0347] C30. According to the method in paragraph C29, determining includes determining that recoil exists when or only when the angular velocity component is outside the threshold angular velocity component range, or determining that recoil does not exist when the angular velocity component is within the threshold angular velocity component range, optionally, wherein the threshold angular velocity component range is defined by angular velocity component values ​​that are at least one of the following:

[0348] (i) at most -1.5 degrees per second (° / s), at most -2° / s, at most -2.5° / s, at most -3° / s, at most -3.5° / s, at most -4° / s, at most -4.5° / s, at most -5° / s, at most -5.5° / s, at most -6° / s, at most -6.5° / s, at most -7° / s, at most -7.5° / s, or at most -8° / s; and

[0349] (ii) at least -12° / s, at least -11.5° / s, at least -11° / s, at least -10.5° / s, at least -10° / s, at least -9.5° / s, at least -9° / s, at least -8.5° / s, at least -8° / s, at least -7.5° / s, at least -7° / s, at least -6.5° / s, at least -6° / s, at least -5.5° / s, at least -5° / s, at least -4.5° / s, or at least -4° / s.

[0350] C31. According to the method in paragraph C30, the angular velocity component is within the threshold angular velocity component range when or only when the rotation about the linear acceleration axis includes the rotation of the tool holder of the handheld power tool toward the workpiece support of the handheld power tool.

[0351] C32. The method described in any of paragraphs C25 to C31, wherein the forgery parameters are determined within the detection time window.

[0352] C33. According to the method in paragraph C32, where the detection time window extends the threshold detection time before the recoil time, at the recoil time, at least one of the following conditions exists:

[0353] (i) The magnitude of the acceleration of the handheld power tool is greater than the threshold acceleration value;

[0354] (ii) The acceleration direction of the handheld power tool is within the threshold direction range; and

[0355] (iii) The angular velocity of the handheld power tool is greater than the threshold angular velocity value.

[0356] C34. According to the method in either paragraph C32 or C33, the detection time window has at least one of the following durations:

[0357] (i) at least 20 milliseconds (ms), at least 30 ms, at least 40 ms, at least 50 ms, at least 60 ms, at least 70 ms, at least 80 ms, at least 90 ms, at least 100 ms, at least 110 ms, at least 120 ms, at least 130 ms, or at least 140 ms; and

[0358] (ii) up to 220ms, up to 210ms, up to 200ms, up to 190ms, up to 180ms, up to 170ms, up to 160ms, up to 150ms, up to 140ms, up to 130ms, up to 120ms, up to 110ms or up to 100ms.

[0359] C35. The method according to any of paragraphs C25 to C34, wherein the falsified parameters include the linear acceleration direction component of the acceleration of the handheld power tool.

[0360] C36. According to the method in paragraph C35, the linear acceleration directional component is at least one of the following:

[0361] (i) Pointing to one / the leading edge of the handheld power tool;

[0362] (ii) Keep away from the user's orientation when using handheld power tools;

[0363] (iii) The user actuation assembly of the workpiece support is facing away from the handheld power tool and is oriented to the side.

[0364] C37. The method according to either paragraph C35 or C36, wherein the linear acceleration direction component is within a threshold angle range in the cutting direction of the handheld power tool, optionally wherein the threshold angle range is defined by at least one of the following degrees:

[0365] (i) at least 0°, at least -30°, at least -45°, at least -60°, or at least -80°; and

[0366] (ii) up to 80°, up to 60° or up to 45°.

[0367] C38. The method according to any one of paragraphs C1 to C37, wherein the handheld power tool includes at least one of the following saws:

[0368] (i) Circular saw;

[0369] (ii) Handheld circular saw;

[0370] (iii) Bevel saw;

[0371] (iv) Splitting saw;

[0372] (v) Rotary power tools;

[0373] (vi) Handheld rotary power tools;

[0374] (vii) Handheld rotary cutter;

[0375] (viii) Handheld polisher;

[0376] (ix) Handheld grinders; and

[0377] (x) Hand-held drilling rig. C39. According to the method of any of paragraphs C1 to C38, wherein the hand-held power tool includes any suitable structure of any circular saw in any of paragraphs A1 to A25.

[0378] D1. The use of a motion sensor for detecting recoil of an entry saw, said motion sensor being incorporated into a user actuation assembly of the entry saw.

[0379] D2. The use of any circular saw in any of paragraphs A1 to A25 in conjunction with any method in any of paragraphs B1 to C39.

[0380] D3. Any method of any of paragraphs B1 to C39 used in conjunction with any circular saw in any of paragraphs A1 to A25.

[0381] Industrial applicability

[0382] The handheld power tools, circular saws, and methods disclosed in this article are applicable to the power tool industry.

[0383] It is believed that the above disclosure covers several different inventions with independent utility. While each of these inventions is disclosed in its preferred form, the specific embodiments of these inventions disclosed and illustrated herein should not be considered limiting, as many variations are possible. The subject matter of this invention includes all novel and non-obvious combinations and sub-combinations of the various elements, features, functions, and / or characteristics disclosed herein. Similarly, where a claim enumerates a "one" or "first" element or its equivalent, such a claim should be understood to include the incorporation of one or more such elements, neither requiring nor excluding two or more such elements.

[0384] It is believed that the appended claims specifically point to certain combinations and sub-combinations of features, functions, elements, and / or characteristics that are novel and non-obvious, relating to one of the disclosed inventions. Other combinations and sub-combinations of features, functions, elements, and / or characteristics may be claimed by amending the current claims or by setting new claims in this or related applications. These amended or new claims, whether they pertain to different or the same invention, and whether their scope differs from, is broader, narrower, or identical to that of the original claims, are also considered to be included within the subject matter of the invention disclosed herein.

Claims

1. A method for detecting the recoil condition of a circular saw, the circular saw including a circular saw blade, a workpiece support, and a user-actuated assembly configured to rotate relative to the workpiece support to cause the circular saw blade to cut a workpiece, the method comprising: The circular saw blade rotates within the blade's plane of rotation. Detecting the movement of the user-actuated component, wherein detecting the movement includes at least one of the following: (ai) Detects the magnitude of the acceleration of the user actuation component in the acceleration detection plane, which is parallel to the blade rotation plane or on the same plane as the blade rotation plane; (a-ii) Detect the acceleration direction of the user actuation component in the acceleration detection plane; (a-iii) Detect the angular velocity of the user actuation component about at least one rotational detection axis extending in the acceleration detection plane; as well as The presence of the recoil condition is determined at least in part based on verification parameters including the motion of the user-actuated component, wherein the presence of the recoil condition is determined to be present in at least one of the following conditions: (i) When detecting the magnitude of the acceleration of the user actuation component, if the magnitude of the acceleration of the user actuation component is greater than a threshold acceleration value, it is determined that the recoil condition exists; (ii) When the acceleration direction of the user actuation component is detected, if the acceleration direction of the user actuation component is within a threshold direction range, it is determined that the recoil condition exists; (iii) When the angular velocity of the user actuation component is detected, if the angular velocity of the user actuation component is greater than a threshold angular velocity value, it is determined that the recoil condition exists.

2. A method for detecting the recoil condition of a circular saw, the circular saw including a circular saw blade, a workpiece support, and a user-actuated assembly configured to rotate relative to the workpiece support to cause the circular saw blade to cut a workpiece, the method comprising: The circular saw blade rotates within the blade's plane of rotation. The magnitude of the acceleration of the user actuation component in the acceleration detection plane is detected, and the acceleration detection plane is parallel to the blade rotation plane or on the same plane as the blade rotation plane. The direction of acceleration of the user actuation component within the acceleration detection plane is detected; The angular velocity of the user actuation component about at least one rotational detection axis extending in the acceleration detection plane is detected; as well as The recoil condition is determined to exist under at least one of the following conditions: (i) The magnitude of the acceleration of the user-actuated component is greater than a threshold acceleration value; (ii) The acceleration direction of the user actuation component is within the threshold direction range; (iii) The angular velocity of the user-actuated component is greater than the threshold angular velocity value.

3. The method according to claim 1 or 2, wherein the detection further includes detecting workpiece contact parameters, wherein, When the circular saw blade contacts the workpiece, the workpiece contact parameter is within the contact value range, wherein when the circular saw blade is spaced apart from the workpiece, the workpiece contact parameter is within the non-contact value range, wherein the verification parameter further includes the workpiece contact parameter and / or wherein the method includes determining that the recoil condition exists when the workpiece contact parameter is within the contact value range.

4. The method according to claim 3, wherein, The workpiece contact parameters include the angular velocity of the circular saw blade during rotation, wherein the circular saw blade defines a mean free angular velocity when it is spaced apart from the workpiece, and wherein the contact value range includes an angular velocity that is less than a lower threshold angular velocity than the mean free angular velocity.

5. The method of claim 3, wherein the workpiece contact parameter includes the power consumption of the circular saw during rotation, wherein the motor of the circular saw is limited to a maximum rated power consumption, and the contact value range includes power consumption greater than a threshold percentage of the maximum rated power consumption.

6. The method according to claim 3, wherein, The circular saw includes a contact detector configured to detect contact between the circular saw blade and the workpiece, wherein the contact detector is configured to generate contact parameters for the workpiece.

7. The method according to claim 1 or 2, wherein, Detecting the magnitude of the acceleration includes: detecting a first acceleration component in a first direction within the acceleration detection plane; and detecting a second acceleration component in a second direction within the acceleration detection plane and perpendicular to the first direction, wherein the magnitude of the acceleration is determined based on the first acceleration component and the second acceleration component.

8. The method according to claim 7, wherein, Detecting the acceleration direction includes detecting the first acceleration component and detecting the second acceleration component, wherein the acceleration direction is the direction of the vector sum of the first acceleration component and the second acceleration component.

9. The method of claim 7, wherein detecting the angular velocity of the user actuation component comprises detecting a first angular velocity component about the first direction and detecting a second angular velocity component about the second direction, and wherein the angular velocity of the user actuation component is a vector sum of the first angular velocity component and the second angular velocity component.

10. The method according to claim 1 or 2, wherein the threshold acceleration value is at least 1 meter per square second (m / s²). 2 ).

11. The method according to claim 1 or 2, wherein the threshold direction range is at least one of the following: (i) pointing backward relative to the cutting direction of the circular saw; (ii) Point away from the workpiece being cut by the circular saw.

12. The method according to claim 1 or 2, wherein the threshold direction range is within a threshold angle range in the cutting direction of the circular saw, wherein the threshold angle range is oriented to the side away from the user actuation component facing the workpiece support of the circular saw, and is at least 80 degrees and at most 180 degrees.

13. The method of claim 1 or 2, wherein the workpiece support defines a workpiece facing side, a workpiece opposite side, a leading edge, and a trailing edge, including at least one of the following: (i) At least a portion of the acceleration direction within the threshold direction range is perpendicular to the opposite side of the workpiece of the workpiece support; (ii) At least a portion of the acceleration direction within the threshold direction range is directed toward the trailing edge of the workpiece support; (iii) The threshold direction range is limited to a quadrant that extends between a first vector and a second vector, the first vector pointing to the trailing edge of the workpiece support and along the opposite side of the workpiece support, and the second vector intersecting the first vector and perpendicular to the opposite side of the workpiece support.

14. The method according to claim 1 or 2, wherein the threshold angular velocity value is at least 1 degree per second (° / s).

15. The method of claim 1 or 2, wherein the threshold angular velocity value includes an angular velocity that causes the blade of the workpiece support of the circular saw to move away from the workpiece.

16. The method according to claim 1 or 2, wherein, After initiating the rotation and simultaneously with the detection, the method further includes cutting the workpiece with the circular saw blade.

17. The method of claim 1 or 2, wherein the method further comprises responding to determining that the recoil condition exists.

18. The method of claim 17, wherein the response includes interrupting the rotation.

19. The method of claim 17, wherein, The method includes initiating the response for various conditions that determine the existence of the recoil condition.

20. The method of claim 1 or 2, wherein the method further comprises applying a spoofing parameter, and wherein determining whether the recoil condition exists is at least in part based on the spoofing parameter.

21. The method according to claim 20, wherein, The forged parameters include at least one of the following: (a) The linear acceleration component of the circular saw; (b) The angular velocity component of the circular saw, wherein the angular velocity component is about the angular velocity axis. Wherein, the linear acceleration component is in the linear acceleration direction, and the linear acceleration direction is at least one of the following: (i) The blade rotation plane is parallel to the circular saw blade; (ii) The assembly facing side of the workpiece support member parallel to the circular saw; (iii) Parallel to the longitudinal axis of the groove defined by the circular saw blade within the workpiece.

22. The method of claim 21, wherein determining whether the recoil condition exists includes one of the following: (i) When the linear acceleration component is outside the range of the threshold linear acceleration component, it is determined that the recoil condition exists; (ii) When the linear acceleration component is within the range of the threshold linear acceleration component, it is determined that the recoil condition does not exist.

23. The method of claim 21, wherein determining whether the recoil condition exists includes one of the following: (i) When the angular velocity component is outside the range of the threshold angular velocity component, it is determined that the recoil condition exists; (ii) When the angular velocity component is within the range of the threshold angular velocity component, it is determined that the recoil condition does not exist.

24. The method of claim 21, wherein the direction of the linear acceleration coincides with the axis of angular velocity.

25. The method according to claim 23, wherein, When rotation about a linear acceleration axis extending in the linear acceleration direction includes rotation of the circular saw's spindle toward the circular saw's workpiece support, the angular velocity component is within the threshold angular velocity component range.

26. The method of claim 21, wherein the forgery parameter is determined within a detection time window.

27. The method of claim 26, wherein the detection time window extends the threshold detection time prior to the recoil time, at the recoil time, at least one of the following conditions exists: (i) The acceleration of the circular saw is greater than the threshold acceleration value; (ii) The acceleration direction of the circular saw is within the range of the threshold direction; (iii) The angular velocity of the circular saw is greater than the threshold angular velocity value.

28. The method of claim 26, wherein during at least a subset of the detection time window, the linear acceleration component is within a threshold linear acceleration component range; and / or During at least a subset of the detection time window, the angular velocity component is within the threshold angular velocity component range.

29. The method according to claim 1 or 2, wherein the circular saw comprises any one of the following circular saws: (i) Handheld circular saw; (ii) Semi-fixed circular saw.

30. A circular saw, comprising: User-actuated components include: (i) a motion sensor configured to detect the motion of the user actuation component in an acceleration detection plane and generate a motion signal indicating the motion of the user actuation component, the acceleration detection plane being parallel to or coplanar with the blade rotation plane; and (ii) A controller programmed to control the operation of the circular saw based at least in part on the motion signal, wherein the controller is programmed to perform the method according to any one of claims 1 to 29; A workpiece support configured to position the workpiece and the circular saw relative to each other when the circular saw cuts the workpiece; and A pivot, wherein the user actuation component is pivotally coupled to the workpiece support via the pivot, wherein the user actuation component and the workpiece support are configured to be operably rotated relative to each other about the pivot axis of the pivot to cause the circular saw blade to cut the workpiece.

31. A circular saw, comprising: User-actuated components include: (i) A motion sensor configured to detect the motion of the user actuation component in an acceleration detection plane and generate a motion signal indicating the motion of the user actuation component, the acceleration detection plane being parallel to or on the same plane as the blade rotation plane; (ii) a controller programmed to control the operation of the circular saw based at least in part on the motion signals; and (iii) A motor, comprising a motor shaft configured to rotate about a rotation axis; A workpiece support configured to position the workpiece and the circular saw relative to each other when the circular saw cuts the workpiece; and A pivot, wherein the user actuation component is pivotally coupled to the workpiece support via the pivot, wherein the user actuation component and the workpiece support are configured to be operably rotated relative to each other about the pivot axis of the pivot to cut a workpiece. The motion sensor is configured to detect acceleration along an acceleration detection axis, wherein the acceleration detection axis extends from the pivot axis to a threshold pivot axis-acceleration axis distance, wherein the threshold pivot axis-acceleration axis distance is at most 4 centimeters.

32. The circular saw of claim 31, wherein the acceleration detection axis extends through the pivot axis.

33. The circular saw according to claim 31 or 32, wherein the motion sensor is configured to detect acceleration in an acceleration detection plane, the acceleration detection plane being at least one of the following: (i) Rotation axis perpendicular to the axis; (ii) Perpendicular to the pivot axis; (iii) Parallel to the plane of rotation of the circular saw blade that rotates therein during operation of the circular saw.

34. The circular saw according to claim 31 or 32, wherein the motion sensor is positioned at a threshold pivot axis-sensor distance from the pivot axis, wherein the threshold pivot axis-sensor distance is at least 1 cm and at most 20 cm.

35. The circular saw according to claim 31 or 32, wherein the acceleration detection axis extends perpendicular to the pivot axis.

36. The circular saw according to claim 31 or 32, wherein the acceleration detection axis extends radially relative to the axis of rotation of the shaft.

37. The circular saw according to claim 31 or 32, wherein the circular saw comprises any one of the following: (i) Handheld circular saw; (ii) Semi-fixed circular saw.

38. A method for detecting recoil in a handheld power tool, the handheld power tool including a workpiece support and a user actuation assembly configured to rotate relative to the workpiece support to cause an instrument of the handheld power tool to cut a workpiece, the method comprising: The device is moved within its plane of motion. The motion of the user actuation component in the acceleration detection plane is detected, and the acceleration detection plane is parallel to the device motion plane or is on the same plane as the device motion plane. Apply forged parameters; as well as The presence of the recoil condition is determined based on verification parameters including the motion of the user-actuated component and based on the spoofed parameters.

39. A method for detecting recoil in a handheld power tool, the handheld power tool including a workpiece support and a user actuation assembly configured to rotate relative to the workpiece support to cause an instrument of the handheld power tool to cut a workpiece, the method comprising: The device is moved within its plane of motion. The motion of the user actuation component and the workpiece contact parameters are detected in the acceleration detection plane, which is parallel to the motion plane of the instrument or on the same plane as the motion plane of the instrument. Apply forged parameters; as well as The existence of the recoil condition is determined based on verification parameters including the motion of the user actuation component and the workpiece contact parameters, and based on the spoofing parameters, wherein the workpiece contact parameters are within the contact value range when the instrument is in contact with the workpiece, and wherein the workpiece contact parameters are within the non-contact value range when the instrument is spaced apart from the workpiece.

40. The method of claim 38 or 39, wherein detecting motion comprises at least one of the following: (ai) detects the magnitude of the acceleration of the user-actuated component; (a-ii) Detect the acceleration direction of the user actuation component; (a-iii) Detect the angular velocity of the user actuation component.

41. The method of claim 40, wherein the recoil condition is determined to exist in at least one of the following conditions: (i) When detecting the magnitude of the acceleration of the user actuation component, if the magnitude of the acceleration of the user actuation component is greater than a threshold acceleration value, it is determined that the recoil condition exists; (ii) When the acceleration direction of the user actuation component is detected, if the acceleration direction of the user actuation component is within a threshold direction range, it is determined that the recoil condition exists; (iii) When the angular velocity of the user actuation component is detected, if the angular velocity of the user actuation component is within a threshold angular velocity value, it is determined that the recoil condition exists.

42. The method of claim 40, wherein the forged parameter comprises at least one of the following: (a) The linear acceleration component of the acceleration of the handheld power tool; (b) The angular velocity component of the angular velocity of the handheld power tool; (c) The linear acceleration direction component of the acceleration of the handheld power tool.

43. The method of claim 42, wherein determining whether the recoil condition exists includes one of the following: (i) When the linear acceleration component is outside the range of the threshold linear acceleration component, it is determined that the recoil condition exists; (ii) When the linear acceleration component is within the range of the threshold linear acceleration component, it is determined that the recoil condition does not exist.

44. The method of claim 42, wherein determining whether the recoil condition exists includes one of the following: (i) When the angular velocity component is outside the range of the threshold angular velocity component, it is determined that the recoil condition exists; (ii) When the angular velocity component is within the range of the threshold angular velocity component, it is determined that the recoil condition does not exist.

45. The method of claim 42, wherein the direction of the linear acceleration coincides with the angular velocity axis of the angular velocity.

46. ​​The method of claim 38 or 39, wherein the forgery parameter is determined within a detection time window.

47. The method of claim 46, wherein the detection time window extends the threshold detection time prior to the recoil time, at the recoil time, at least one of the following conditions exists: (i) The acceleration of the handheld power tool is greater than the threshold acceleration value; (ii) The acceleration direction of the handheld power tool is within the threshold direction range; (iii) The angular velocity of the handheld power tool is greater than the threshold angular velocity value.

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