Power tool comprising a high-power motor

Abstract

An electric tool includes a housing and a motor supported within the housing. The motor includes a stator and a rotor. The rotor is disposed within the stator. The stator includes a stator lamination stack, a plurality of stator teeth, and a plurality of stator coils. The stator lamination stack includes an outer wall, wherein the length of the stator lamination stack is approximately 6.00 mm to 15.00 mm. The plurality of stator teeth extend radially inward from the outer wall. The rotor includes a rotor lamination stack and a plurality of magnets. The rotor lamination stack includes a plurality of magnet slots. The length of the rotor lamination stack is approximately 6.00 mm to 15.00 mm. Each of the plurality of magnets is disposed within a magnet slot in one of the plurality of magnet slots. The ratio of the stator tooth width to the outer wall thickness of the stator is approximately 1.8 to 2.5.

Description

[0001] Related applications This application claims priority to U.S. Provisional Patent Application No. 63 / 898,737, filed October 14, 2025; U.S. Provisional Patent Application No. 63 / 816,273, filed June 2, 2025; and U.S. Provisional Patent Application No. 63 / 777,949, filed March 26, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This invention relates to electric tool motors. Summary of the Invention

[0003] The embodiments described in this invention relate to power tools that include a high-power motor, which provides increased power output and efficiency compared to existing motors of comparable size.

[0004] The motor assembly of the present invention includes a stator and a rotor. The stator includes a stator lamination stack, the stator lamination stack including an outer wall, wherein the length of the stator lamination stack is approximately 6.0 mm to 15.00 mm, a plurality of stator teeth extending radially inward from the outer wall, and a plurality of stator coils. The rotor is disposed within the stator. The rotor includes a rotor lamination stack and a plurality of magnets, the rotor lamination stack including a plurality of magnet slots, wherein the length of the rotor lamination stack is approximately 6.00 mm to 15.00 mm, and each of the plurality of magnets is disposed within a magnet slot of the plurality of magnet slots. The ratio of the stator tooth width to the outer wall thickness of the stator is approximately 1.8 to 2.5.

[0005] The motor assembly of the present invention includes a stator and a rotor disposed within the stator. The rotor includes a rotor lamination stack and a plurality of magnets, the rotor lamination stack including a plurality of magnet slots, wherein the length of the rotor lamination stack is greater than about 8.00 mm, and each of the plurality of magnets is disposed within a magnet slot of the plurality of magnet slots.

[0006] The motor assembly of the present invention includes a stator and a rotor. The stator includes a stator lamination stack, the stator lamination stack including an outer wall, wherein the length of the stator lamination stack is greater than about 8.00 mm, a plurality of stator teeth extending radially inward from the outer wall, and a plurality of stator coils. The rotor is disposed within the stator. The ratio of the stator tooth width to the outer wall thickness of the stator is about 1.8 to 2.5.

[0007] The power tool of the present invention includes a housing and a motor supported within the housing. The motor includes a stator and a rotor. The rotor is disposed within the stator. The stator includes a stator lamination stack, a plurality of stator teeth, and a plurality of stator coils. The stator lamination stack includes an outer wall, wherein the length of the stator lamination stack is approximately 6.00 mm to 15.00 mm. The plurality of stator teeth extend radially inward from the outer wall. The rotor includes a rotor lamination stack, which includes a plurality of magnet slots and a plurality of magnets. The length of the rotor lamination stack is approximately 6.00 mm to 15.00 mm. Each of the plurality of magnets is disposed within a magnet slot in one of the plurality of magnet slots. The ratio of the stator tooth width to the outer wall thickness of the stator is approximately 1.8 to 2.5.

[0008] Before explaining any embodiment in detail, it should be understood that the embodiments are not limited in application to the details of the configuration and arrangement of the components set forth in the following description or shown in the accompanying drawings. The embodiments can be practiced or performed in various ways. Furthermore, it should be understood that the wording and terminology used in this invention are for descriptive purposes and should not be considered limiting. The use of “comprising,” “including,” or “having,” and variations thereof is intended to cover the items listed thereafter and their equivalents, as well as additional items. Unless otherwise stated or limited, the terms “installation,” “connection,” “support,” and “linkage,” and variations thereof are used extensively and cover direct and indirect installation, connection, support, and linking.

[0009] Unless the context clearly indicates otherwise, the articles “a” and “the” should not be interpreted as meaning “one” or “only one.” Rather, these articles should be interpreted as meaning “at least one” or “one or more.” Similarly, when the terms “the” or “the” are used to refer to a noun previously introduced by the indefinite article “a,” “the” and “the” mean “at least one” or “one or more,” unless the usage clearly indicates otherwise.

[0010] Furthermore, it should be understood that embodiments may include hardware, software, and electronic components or modules, which, for the purposes of discussion, are illustrated and described as if most components were implemented solely in hardware. However, those skilled in the art, based on reading this particular embodiment, will recognize that in at least one embodiment, the electronic aspects may be implemented in software (e.g., stored on a non-transitory computer-readable medium) executable by one or more processing units (such as microprocessors and / or application-specific integrated circuits (“ASICs”)). Therefore, it should be noted that embodiments may be implemented using multiple hardware and software-based devices and multiple different structural components. For example, “server,” “computing device,” “controller,” “processor,” etc., described in the specification may include one or more processing units, one or more computer-readable medium modules, one or more input / output interfaces, and various connections of connecting components (e.g., system buses).

[0011] Relative terms used in conjunction with quantities or conditions, such as “about,” “approximately,” “substantially,” etc., will be understood by a person skilled in the art to include the stated value and have a meaning prescribed by the context (e.g., the term includes at least the degree of error associated with measurement accuracy, the tolerance associated with a particular value [e.g., manufacturing, assembly, use, etc.]). Such terms should also be considered to disclose a range defined by the absolute values ​​of the two endpoints. For example, the statement “about 2 to about 4” also discloses a range of “2 to 4.” Relative terms may refer to percentages added to or subtracted from the indicated value (e.g., 1%, 5%, 10%).

[0012] It should be understood that although some figures illustrate hardware and software residing within a particular device, these descriptions are for illustrative purposes only. Functions described herein as being performed by a single component can be performed by multiple components in a distributed manner. Similarly, functions performed by multiple components can be combined and performed by a single component. In some embodiments, the components shown may be combined or divided into separate software, firmware, and / or hardware. For example, logic and processing may be distributed among multiple electronic processors, rather than residing within and being performed by a single electronic processor. Regardless of how the hardware and software components are combined or divided, they may reside on the same computing device or be distributed among different computing devices connected via one or more networks or other suitable communication links. Similarly, components described as performing specific functions may also perform additional functions not described herein. For example, a device or structure "configured" in a certain way is at least configured in that way, but may also be configured in ways not explicitly listed.

[0013] Therefore, in the claims, if the apparatus, method, or system is claimed to include, for example, a controller, control unit, electronic processor, computing device, logic element, module, memory module, communication channel or network, or other elements configured in a certain way to perform, for example, multiple functions, then the elements involved in the claims should be interpreted as referring to one or more such elements, wherein any one of the one or more elements is configured as claimed, for example, to implement any one or more of the multiple functions, such that the one or more elements together perform the multiple functions as a set.

[0014] Other aspects of the invention will become apparent from the specific embodiments and accompanying drawings. Attached Figure Description

[0015] Figure 1 A perspective view of a power tool according to some embodiments is shown.

[0016] Figure 2 Illustrations are shown according to some embodiments Figure 1 A block diagram of the control system of a power tool.

[0017] Figure 3 The diagram illustrates the relationship between [various embodiments] and [other embodiments]. Figure 1 A battery pack used in conjunction with power tools.

[0018] Figure 4 Illustrations are shown according to some embodiments Figure 3 A block diagram of the control system for the battery pack.

[0019] Figure 5 A perspective view of a power tool motor according to an embodiment described in this invention is shown.

[0020] Figure 6 An embodiment according to the present invention is shown. Figure 5 Side view of the motor of an electric tool.

[0021] Figure 7 An embodiment according to the present invention is shown. Figure 5 A top view of the motor of a power tool.

[0022] Figure 8 An embodiment according to the present invention is shown. Figure 5 A bottom view of the motor of an electric tool.

[0023] Figure 9 An embodiment described according to the present invention is shown. Figure 5 A perspective view of the stator of an electric tool motor.

[0024] Figure 10An embodiment described according to the present invention is shown. Figure 5 A top view of the stator of an electric tool motor.

[0025] Figure 11 An embodiment described according to the present invention is shown. Figure 10 A top view of the stator insulator of the stator.

[0026] Figure 12 An embodiment described according to the present invention is shown. Figure 10 A top view of the stator lamination stack.

[0027] Figure 13 An embodiment described according to the present invention is shown. Figure 5 A partial sectional view of the stator of an electric tool motor.

[0028] Figure 14 An embodiment according to the present invention is shown. Figure 10 A partial top view of the stator lamination stack.

[0029] Figure 15 An embodiment described according to the present invention is shown. Figure 5 A perspective view of the rotor of a power tool motor.

[0030] Figure 16 An embodiment according to the present invention is shown. Figure 5 A side view of the rotor of a power tool motor.

[0031] Figure 17 An embodiment described according to the present invention is shown. Figure 5 A perspective view of the rotor of a power tool motor.

[0032] Figure 18 An embodiment according to the present invention is shown. Figure 5 A top view of the rotor of a power tool motor.

[0033] Figure 19 This is a graph illustrating the performance characteristics of the motor described in this invention.

[0034] Figure 20 This is a graph illustrating the performance characteristics of the motor described in this invention.

[0035] Figure 21 This is a graph showing the thermal performance of the motor described in this invention. Detailed Implementation

[0036] The embodiments described in this invention relate to power tools including a motor with improved motor performance. Improved motor performance is achieved by using a motor having substantially the same external dimensions (e.g., dimensional parameters) or smaller.

[0037] Figure 1 A power tool 100 including a motor (also referred to as a motor assembly) is shown. The power tool 100 is, for example, a hammer drill including a housing 102. Although Figure 1 A hammer drill is shown, but in some embodiments, the components described herein are incorporated into other types of power tools, including electric drills, impact screwdrivers, impact wrenches, angle grinders, circular saws, reciprocating saws, plate compactors, core drills, trimmers, leaf blowers, vacuum cleaners, or other suitable applications where motor operation can be achieved using a weak magnetic field. Housing 102 includes a handle portion 104 and a motor housing portion 106. Power tool 100 also includes an output driver 108 (shown as a chuck), a trigger 110, and a battery pack interface 112. The battery pack interface 112 is configured to be mechanically and electrically connected to or receive a power tool battery pack. In power tools such as power tool 100, switching elements are selectively enabled and disabled via control signals from a controller to selectively apply power from a power source (e.g., a battery pack) to drive the motor.

[0038] Figure 2 A control system 200 for a power tool 100 is shown. The control system 200 includes a controller 202. The controller 202 is electrically and / or communicatively connected to various modules or components of the power tool 100. For example, the controller 202 is electrically connected to a motor 204, a battery interface 206, a trigger switch 208 (connected to a trigger 210), one or more sensors or sensing circuits 212, one or more indicators 214, a user input module 216, a power input module 218, an inverter bridge or FET switching module 220 (e.g., including multiple switching FETs), and a gate driver 224 for driving the FET switching module 220. The controller 202 includes a combination of hardware and software operable to control the operation of the power tool 100, monitor the operation of the power tool 100, activate one or more indicators 214 (e.g., LEDs), etc.

[0039] The controller 202 includes multiple electrical and electronic components that provide power, operation control, and protection to components and modules within the controller 202 and / or the power tool 100. For example, the controller 202 particularly includes a processing unit 226 (e.g., a microprocessor, microcontroller, electronic controller, electronic processor, or other suitable programmable device), a memory 228, an input unit 230, and an output unit 232. The processing unit 226 particularly includes a control unit 234, an arithmetic logic unit (“ALU”) 236, and multiple registers 238, and is implemented using known computer architectures (e.g., modified Harvard architecture, von Neumann architecture, etc.). The processing unit 226, the memory 228, the input unit 230, and the output unit 232, as well as various modules or circuits connected to the controller 202, are connected via one or more control and / or data buses (e.g., a common bus 240). For illustrative purposes, Figure 2 The control and / or data bus is generally shown. It is known to those skilled in the art that, according to the invention described herein, one or more control and / or data buses are used for interconnection and communication between various modules, circuits, and components.

[0040] In some embodiments, controller 202 is configured to control gate driver 224 to drive motor 204 using sensored or sensorless field-oriented control (“FOC”) motor control technology.

[0041] Memory 228 is a non-transitory computer-readable medium, including, for example, a program storage area and a data storage area. The program storage area and data storage area may include combinations of different types of memory, such as ROM, RAM (e.g., DRAM, SDRAM, etc.), EEPROM, flash memory, hard disk, SD card, or other suitable magnetic, optical, physical, or electronic memory devices. Processing unit 226 is connected to memory 228 and executes software instructions that can be stored in RAM of memory 228 (e.g., during execution), ROM of memory 228 (e.g., on a generally permanent basis), or another non-transitory computer-readable medium (such as another memory or disk). Software included in the implementation of power tool 100 may be stored in memory 228 of controller 202. Software includes, for example, firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. Controller 202 is configured to retrieve from memory 228 and execute instructions related to the control processes and methods described in this invention. In other configurations, controller 202 includes additional, fewer, or different components.

[0042] Battery pack interface 206 includes a combination of mechanical components (e.g., guide rails, recesses, latches, etc.) and electrical components (e.g., one or more terminals), configured and operable for connection to a battery pack interface (e.g., mechanical, electrical, and communicative connection). For example, it is provided by battery pack 300 (see...). Figure 3 Power supplied to the power tool 100 is provided to the power input module 218 via the battery pack interface 206. The power input module 218 includes a combination of active and passive components to regulate or control the power received from the battery pack 300 before supplying power to the controller 202. The battery pack interface 206 also supplies power to the FET switching module 220, which switches the FETs to selectively supply power to the motor 204. The battery pack interface 206 also includes, for example, a communication line 242 for providing a communication line or link between the controller 202 and the battery pack 300.

[0043] Sensing circuit 212 includes one or more current sensors, one or more speed sensors, one or more Hall effect sensors, one or more temperature sensors, etc. Indicator 214 includes, for example, one or more light-emitting diodes (“LEDs”). Indicator 214 can be configured to display the status of power tool 100 or information associated with power tool 100. For example, indicator 214 is configured to indicate measured electrical characteristics of power tool 100, the status of power tool, the status of motor 204, etc. User input module 216 is operatively coupled to controller 202 to, for example, select forward or reverse operating mode, torque and / or speed settings of power tool 100 (e.g., using torque and / or speed switches), etc. In some embodiments, user input module 216 includes a combination of digital and analog input or output devices required to achieve a desired level of operation of power tool 100, such as one or more knobs, one or more dials, one or more switches, one or more buttons, etc.

[0044] Figure 3 A battery pack 300 is shown. The battery pack 300 includes a housing 302 and an interface portion 304 for connecting the battery pack 300 to a power tool such as the power tool 100.

[0045] Figure 4 A control system for a battery pack 300 is shown. The control system includes a controller 400. The controller 400 is electrically and / or communicatively connected to various modules or components of the battery pack 300. For example, the controller 400 shown is connected to one or more battery cells 402 and an interface 404 (e.g., Figure 3The interface portion 304 of the battery pack 300 is shown. The controller 400 is also connected to one or more voltage sensors or voltage sensing circuits 406, one or more current sensors or current sensing circuits 408, and one or more temperature sensors or temperature sensing circuits 410. The controller 400 includes a combination of hardware and software operable to control the operation of the battery pack 300, monitor the status of the battery pack 300, enable or disable the charging of the battery pack 300, enable or disable the discharging of the battery pack 300, etc.

[0046] The controller 400 includes multiple electrical and electronic components that provide power, operational control, and protection to parts and modules within the controller 400 and / or battery pack 300. For example, the controller 400 particularly includes a processing unit 412 (e.g., a microprocessor, microcontroller, electronic processor, electronic controller, or other suitable programmable device), a memory 414, an input unit 416, and an output unit 418. The processing unit 412 particularly includes a control unit 420, an ALU 422, and multiple registers 424, and is implemented using known computer architectures (e.g., modified Harvard architecture, von Neumann architecture, etc.). The processing unit 412, memory 414, input unit 416, and output unit 418, as well as various modules or circuits connected to the controller 400, are connected via one or more control and / or data buses (e.g., common bus 426). For illustrative purposes, in Figure 4 The control and / or data bus is generally shown in the diagram. As is known to those skilled in the art, one or more control and / or data buses are used for interconnection and communication between various modules, circuits, and components, according to the embodiments described in this invention.

[0047] Memory 414 is a non-transitory computer-readable medium, including, for example, a program storage area and a data storage area. The program storage area and data storage area may include combinations of different types of memory, such as ROM, RAM (e.g., DRAM, SDRAM, etc.), EEPROM, flash memory, hard disk, SD card, or other suitable magnetic, optical, physical, or electronic memory devices. Processing unit 412 is connected to memory 414 and executes software instructions that can be stored in RAM of memory 414 (e.g., during execution), ROM of memory 414 (e.g., on a generally permanent basis), or another non-transitory computer-readable medium (such as another memory or disk). Software included in the implementation of battery pack 300 may be stored in memory 414 of controller 400. Software includes, for example, firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. Controller 400 is configured to retrieve from memory 414 and execute instructions related to the control processes and methods described in this invention. In other configurations, controller 400 includes additional, fewer, or different components.

[0048] Interface 404 includes a combination of mechanical components (e.g., guide rails, recesses, latches, etc.) and electrical components (e.g., one or more terminals), configured and operable to interface (e.g., mechanically, electrically, and communicatively) battery pack 300 with another device (e.g., power tool, battery charger, etc.). For example, interface 404 is configured to communicatively connect to controller 400 via communication line 428.

[0049] The shape of motor 204 can be adjusted to reduce the total harmonic distortion (THD). THD is a measure of total noise (e.g., higher-frequency harmonics) compared to a basic sinusoidal shape. THD can be expressed as a percentage and can be used to quantify how much a signal deviates from a pure sine wave. The higher the percentage of THD, the more noise and vibration motor 204 generates. Back electromotive force (“back-EMF”) is the voltage induced in the coils of motor 204 due to the rotation of the motor. In an ideal motor, the back-EMF of motor 204 is a pure sine wave. By reducing THD, the back-EMF can be made closer to a sine wave (e.g., less distortion). For example, THD is measured at the no-load speed of motor 204.

[0050] Figure 5-18 A motor 500 for use in a power tool 100 is shown. Now refer to... Figure 5 The example illustration includes a perspective view of motor 500. Motor 500 includes stator 505 and rotor 510 (see reference). Figure 8The motor 500 includes a stator 505 and a rotor shaft 515. The stator 505 includes a stator lamination stack 520, a stator insulator 525, and a plurality of power terminals 530. In the illustrated embodiment, the stator outer diameter of the motor 500 is approximately 50.00 mm. However, in other embodiments, the motor 500 may have different outer diameters (e.g., 40 mm, 45 mm, 60 mm, 70 mm, 80 mm, etc.). The rotor 510 includes a fan 560.

[0051] Figure 6 A side view of a motor 500 used in a power tool 100 is shown. A stator lamination stack 520 has a length L. In some embodiments, the stator lamination stack 520 has a length of approximately 8.00 mm. In other embodiments, the stator lamination stack 520 has a length of approximately 10.00 mm. Reducing the length of the stator lamination stack to 8.00 mm, compared to a stator lamination stack of approximately 10.00 mm, reduces the overall length of the motor 500 by approximately 20%. In some embodiments, the stator lamination stack 520 has a length of approximately 6.00 mm to 15.00 mm. Figure 7 A top view of the motor 500 used in the power tool 100 is shown.

[0052] Figure 8 A bottom view of a motor 500 for use in a power tool 100 is shown. The motor 500 includes a rotor 510. In some embodiments, the rotor 510 is disposed within a stator 505. The stator 505 also includes a plurality of stator coils 540. (About...) Figure 9-14 A more detailed description of stator 505. Figure 9 A perspective view of a stator 505 for use in a motor 500 is shown. The stator 505 includes a plurality of stator teeth 535. A plurality of stator coils 540 are wound on the plurality of stator teeth 535. Figure 10 A top view of a stator 505 for use in a motor 500 is shown. Multiple electrical terminals 530 are electrically connected to multiple stator coils 540 of the stator 505.

[0053] refer to Figure 11 The stator insulator 525 includes a plurality of stator teeth 535. Figure 11In this diagram, stator insulator 525 is shown separately, with other portions of stator 505 removed. Stator insulator 525 is made of a rigid plastic material (e.g., polyamide 46, polyamide 66, nylon 46, liquid crystal polymer, etc.) which may, for example, be overmolded onto stator lamination stack 520. In other embodiments, stator insulator 525 may be made of other materials such as ceramic to reduce the thickness of the stator insulator. For example, a ceramic coating may be sprayed onto stator lamination stack 520 (e.g., instead of molding plastic around stator lamination stack 520). In some embodiments, the ceramic coating is an oxide ceramic coating. Stator insulator 525 includes a total of six teeth 535 projecting inward (e.g., radially extending) from the outer portion of stator insulator 525. Each stator tooth 535 has a width W and a height H. In some embodiments, the width of each stator tooth 535 is approximately 6.00 mm to 7.00 mm (e.g., 6.5 mm). In some embodiments, the height of each stator tooth 535 is approximately 5.50 mm to 7.00 mm (e.g., 6.25 mm).

[0054] refer to Figure 12 The stator lamination stack 520 includes multiple stator teeth 535A. In Figure 12 In the diagram, the stator lamination stack 520 is shown separately, with other portions of the stator 505 removed. The stator lamination stack 520 is made of multiple metal (e.g., steel) laminations stacked together to form the stator lamination stack 520. The stator lamination stack 520 includes a total of six teeth 535A projecting inward from the outer portion of the stator lamination stack 520. Each stator tooth 535A has a width W and a height H. In some embodiments, the width of each stator tooth 535A is approximately 5.00 mm to 7.00 mm (e.g., 6.25 mm). In some embodiments, the height of each stator tooth 535A is approximately 6.00 mm to 8.00 mm (e.g., 6.75 mm).

[0055] like Figure 13 As shown, when the stator lamination stack 520 is combined with the stator insulator 525, the stator insulator 525 is formed as a thin layer on top of the stator lamination stack 520. For example, in the illustrated embodiment, the outer portion of the stator insulator 525 is formed to have a thickness T1. In some embodiments, the thickness T1 is about 0.25 mm or less. In some embodiments, the thickness T1 is about between 0.25 mm and 0.05 mm. Similarly, the inner portion of the stator insulator 525 is formed to have a thickness T2. In some embodiments, the thickness T2 is about 0.20 mm or less. In some embodiments, the thickness T2 is about between 0.30 mm and 0.05 mm. Additionally, as... Figure 14As shown, the stator lamination stack has an outer wall thickness T3. In some embodiments, the thickness T3 is 3.60 mm or less. In some embodiments, the thickness T3 is approximately between 3.60 mm and 1.00 mm. By combining reduced thicknesses T1, T2, and T3 on the stator 505, the motor 500 is able to increase the copper coil of the stator coil 540 by approximately 21%. For example, for a stator with an outer diameter of 50.00 mm, each copper slot 523 in the stator 505 (i.e., the space between adjacent stator teeth 535) has at least 80.00 mm. 2 The area. In another example, for a stator with an outer diameter of 50.00 mm, the area of ​​each copper slot 523 is approximately 80.00 mm². 2 Up to 100.00 mm 2 In some embodiments, the area of ​​each copper slot 523 is at least 1.6 times the outer diameter of the stator. In some embodiments, the area of ​​each copper slot 523 is between 1.6 and 2.0 times the outer diameter of the stator. With an increase in the amount of copper in each stator coil 540, the motor 500 is able to generate greater power with substantially the same overall dimensions (e.g., dimensional parameters) or smaller. In some embodiments, the stator lamination stack 520 has a width W based on the stator teeth 535 (see...). Figure 12 The stator tooth to outer wall thickness ratio is approximately two (2). In some embodiments, the stator lamination 520 has a stator tooth to outer wall thickness ratio of at least 1.9, wherein the width W of the stator tooth 535 is, for example, 6.12 mm, and the outer wall thickness T3 is, for example, 3.10 mm. In some embodiments, the stator lamination 520 has a stator tooth to outer wall thickness ratio between 1.8 and 2.5.

[0056] In some embodiments, a stator tooth to outer wall thickness ratio of about 1.8 to 2.5 (e.g., at least about 1.9) is a defined performance characteristic that enables the motor 500 to deliver higher output and efficiency within a constrained motor form factor. For example, a motor 500 with a stator tooth to outer wall thickness ratio of about 1.8 to 2.5 (e.g., at least about 1.9) increases the available slot volume for copper (e.g., copper filler) while maintaining a sufficiently thick back iron / outer wall to carry the operating flux without oversaturation, allowing the motor 500 to support higher currents with lower coil resistance and reduced copper losses. A stator tooth to outer wall thickness ratio of about 1.8 to 2.5 (e.g., at least about 1.9) also maintains a rigid thermal path from the coil into the lamination stack and outward to the housing, thereby mitigating temperature rise under increased torque and maintaining performance within the operating range. The ratio of stator teeth to outer wall thickness of approximately 1.8 to 2.5 (e.g., at least approximately 1.9) reflects a deliberate balance between slot utilization, magnetic load, heat dissipation, and mechanical robustness, which directly supports the increased power density and improved efficiency described in this invention.

[0057] Figure 15 A perspective view of a rotor 510 for use in a motor 500 is shown. The rotor 510 includes a rotor lamination stack 550, a rotor insulator 555, and a fan 560. In some embodiments, the rotor insulator 555 and the fan 560 are single molded plastic parts. In other embodiments, the rotor insulator and the fan 560 are separate molded plastic parts molded onto the rotor lamination stack 550.

[0058] Figure 16 A side view of the rotor 510 of the motor 500 is shown. In some embodiments, the rotor lamination stack 550 has a length L of approximately 8.00 mm. In other embodiments, the rotor lamination stack 550 has a length L of approximately 10.00 mm. In some embodiments, the rotor lamination stack 550 has a length L between approximately 8.00 mm and 10.00 mm. Reducing the length of the rotor lamination stack to 8.00 mm compared to a rotor lamination stack of approximately 10.00 mm would reduce the overall length of the motor 500 by approximately 20%. In other embodiments, the rotor lamination stack 550 has a length between 6.00 mm and 15.00 mm (e.g., 12.6 mm).

[0059] Figure 17 A perspective view of a rotor lamination stack 550 of rotor 510 is shown. The rotor lamination stack 550 includes a plurality of magnets 545 (e.g., four magnets). The rotor lamination stack 550 also includes an opening in which rotor shaft 515 is disposed. Reference Figure 18The rotor lamination stack 550 includes a plurality of magnet slots 545A configured to receive a plurality of magnets 545. Each magnet 545 has a width W and a length L. In some embodiments, the width W of the magnet 545 is at least about 3.00 mm, and the length L of the magnet is about 14.00 mm (e.g., 6.00 mm to 15.00 mm). Therefore, the motor 500 contains about 20% more magnetic material (e.g., rare earth magnetic material) than motors of similar size. In some embodiments, the width W of the magnet 545 is about 5.00 mm. In some embodiments, the width W of the magnet 545 is about 3.00 mm to 5.00 mm. In some embodiments, the length L of the magnet 545 is about 16.00 mm. In some embodiments, the length L of the magnet 545 is about 6.00 mm to 16.00 mm. The rotor lamination stack 550 also includes a plurality of (e.g., four) beveled cuts on the outer portion of the rotor lamination stack 550. In the illustrated embodiment, the beveled cut is located between adjacent magnets 545 and has an angle θ greater than 90°. In some embodiments, the angle θ is approximately 120°. The beveled cut provides a rotor forming feature that can, for example, reduce total harmonic distortion during operation of the motor 500. In some embodiments, the angle θ of the beveled cut is greater than 90° but less than or approximately equal to 120°. In some embodiments, the diameter of the rotor lamination stack 550 is approximately 26.00 mm. In some embodiments, the diameter of the rotor lamination stack 550 varies depending on the outer diameter of the motor 500.

[0060] Figure 19 Graph 600 illustrates a performance comparison between a conventional motor with a stator outer diameter of 50.00 mm and a stator lamination length of approximately 10.00 mm, and a motor 500 with a stator outer diameter of 50.00 mm and a stator lamination length of approximately 8.00 mm. Graph 600 depicts the efficiency, output power, current, and speed of the conventional motor and motor 500 at corresponding motor torques. Example graphs depict variations in efficiency 605, output power 610, current 615, and speed 620 of motor 500 and the conventional motor within their respective motor torque ranges, as well as variations in efficiency 606, output power 611, current 616, and speed 621 of the conventional motor. Figure 19 As shown, the motor 500 with a shorter lamination stack length is able to produce substantially the same output power and efficiency as a larger existing motor. These improvements in output power and efficiency of the smaller motor 500 compared to the larger existing motor stem from improvements described in this invention related to, for example, stator insulator thickness, increased magnet size, and increased copper in the stator coil 540.

[0061] Figure 20Graph 700 shows a performance comparison between a conventional motor with a stator outer diameter of 50.00 mm and a stator lamination length of approximately 10.00 mm, and a motor 500 with the same stator outer diameter and length. Graph 700 depicts the efficiency, output power, current, and speed of the conventional motor and motor 500 at corresponding motor torques. Example graphs depict variations in efficiency 705, output power 710, current 715, and speed 720 of motor 500 and the conventional motor within their respective motor torque ranges, as well as variations in efficiency 706, output power 711, current 716, and speed 721 of the conventional motor. Figure 20 As shown, a motor 500 with the same lamination stack length can produce approximately 20% more power (i.e., at peak power) and approximately 5-10% higher efficiency than existing motors. These improvements in output power and efficiency of the same-sized motor 500 compared to existing motors of comparable size stem from improvements described in this invention related to, for example, stator insulator thickness, increased magnet size, and increased copper in the stator coil 540.

[0062] Figure 21 The heat loss of Motor 500 (using an 8.00 mm stator lamination length and approximately 10.00 mm stator lamination length) is shown compared to that of an existing motor with the same stator outer diameter and approximately 10.00 mm stator lamination length. For example... Figure 21 As shown, the motor 500 with a smaller stator lamination length of 8.00 mm has heat losses that are substantially equivalent to those of conventional motors. However, compared to conventional motors, the motor 500 with a stator lamination length of 10.00 mm produces significantly less heat loss with increased torque. For example, at peak power (approximately 0.65 Nm of torque), the motor 500 with a stator lamination length of 10.00 mm exhibits approximately 30% lower heat loss compared to conventional motors (e.g., heat loss is reduced from approximately 375 W in conventional motors to approximately 250 W in motor 500).

[0063] In some embodiments, the rotor lamination stack has a length between 6.00 mm and 15.00 mm (e.g., 12.6 mm), and the stator lamination stack has a length between 6.00 mm and 15.00 mm (e.g., 12.6 mm). For motors with these lamination stack lengths (e.g., not between 8.00 mm and 10.00 mm), the motors are able to provide similar performance benefits (i.e., increased power, improved efficiency, etc.) as the disclosed motors with 8.00 mm and 10.00 mm lamination stack lengths.

[0064] Therefore, the embodiments described in this invention provide power tool motors with improved motor performance. Although the invention has been described in detail with reference to certain preferred embodiments, variations and modifications are possible within the scope and spirit of one or more independent aspects of the invention described.

Claims

1. A motor assembly, comprising: Stator, the stator comprising: A stator lamination stack, the stator lamination stack including an outer wall, wherein the length of the stator lamination stack is approximately 6.0 mm to 15.00 mm. Multiple stator teeth extending radially inward from the outer wall, and Multiple stator coils; and Rotor, the rotor being disposed within the stator, the rotor comprising: A rotor lamination stack, the rotor lamination stack including a plurality of magnet slots, wherein the length of the rotor lamination stack is approximately 6.00 mm to 15.00 mm, and A plurality of magnets, wherein each of the plurality of magnets is disposed within a magnet slot in one of the plurality of magnet slots. The ratio of the stator tooth width to the outer wall thickness of the stator is approximately 1.8 to 2.

5.

2. The motor assembly as claimed in claim 1, wherein, The outer diameter of the stator is approximately 50 mm.

3. The motor assembly as claimed in claim 1, wherein, The outer diameter of the stator is selected from the following group: 40mm, 45mm, 60mm, 70mm and 80mm.

4. The motor assembly as claimed in claim 1, wherein, The width of the plurality of stator teeth is approximately 6.00 mm to 7.00 mm.

5. The motor assembly as claimed in claim 1, wherein, The height of the plurality of stator teeth is approximately 5.50 mm to 7.00 mm.

6. The motor assembly as claimed in claim 1, wherein, The thickness of the outer wall is less than or equal to about 3.10 mm.

7. The motor assembly of claim 6, wherein, The thickness of the outer wall is greater than approximately 1.00 mm.

8. The motor assembly as claimed in claim 1, wherein, The stator includes a plurality of slots formed by the outer wall and the plurality of stator teeth.

9. The motor assembly of claim 1, wherein the area of ​​each of the plurality of magnet slots is at least 80.00 mm². 2 The outer diameter of the stator is 50 mm.

10. The motor assembly of claim 1, wherein, The stator includes a stator insulator covering the stator lamination stack, the stator insulator comprising an outer portion and an inner portion.

11. The motor assembly of claim 10, wherein, The thickness of the outer portion is less than or equal to about 0.30 mm.

12. The motor assembly of claim 10, wherein, The thickness of the internal portion is less than or equal to about 0.20 mm.

13. The motor assembly of claim 1, wherein, The width of the plurality of magnets is approximately 3.00 mm to 4.00 mm.

14. The motor assembly of claim 1, wherein, The lengths of the plurality of magnets are approximately 6.00 mm to 15.00 mm.

15. The motor assembly of claim 1, wherein, The ratio of the stator tooth width to the stator outer wall thickness is approximately 1.

9.

16. A motor assembly, comprising: stator; and Rotor, the rotor being disposed within the stator, the rotor comprising: A rotor lamination stack, comprising multiple magnet slots, wherein the length of the rotor lamination stack is greater than approximately 6.00 mm, and A plurality of magnets, wherein each of the plurality of magnets is disposed within a magnet slot in the plurality of magnet slots.

17. The motor assembly of claim 16, wherein the outer diameter of the stator is approximately 50 mm.

18. The motor assembly of claim 16, wherein, The outer diameter of the stator is selected from the following group: 40mm, 45mm, 60mm, 70mm and 80mm.

19. The motor assembly of claim 16, wherein, The length of the rotor lamination stack is less than about 10.00 mm.

20. The motor assembly of claim 16, wherein the width of the plurality of magnets is greater than about 3.00 mm.

21. The motor assembly of claim 20, wherein, The width of the plurality of magnets is less than approximately 4.00 mm.

22. The motor assembly of claim 16, wherein the length of the plurality of magnets is greater than about 6.00 mm.

23. The motor assembly of claim 22, wherein the length of the plurality of magnets is less than about 15.00 mm.

24. The motor assembly of claim 16, wherein, The rotor lamination stack includes multiple inclined cuts on the outer portion of the rotor lamination stack.

25. The motor assembly of claim 24, wherein the angle of the plurality of inclined cuts is greater than 90°.

26. The motor assembly of claim 25, wherein, The angles of the plurality of inclined cuts are less than or approximately 120°.

27. A motor assembly, comprising: Stator, the stator comprising: A stator lamination stack, including an outer wall, wherein the length of the stator lamination stack is greater than about 6.00 mm. Multiple stator teeth extending radially inward from the outer wall, and Multiple stator coils; and Rotor, the rotor being disposed within the stator, The ratio of the stator tooth width to the outer wall thickness of the stator is approximately 1.8 to 2.

5.

28. The motor assembly of claim 27, wherein, The length of the stator lamination stack is less than about 15.00 mm.

29. The motor assembly of claim 27, wherein, The outer diameter of the stator is at least about 50 mm.

30. The motor assembly of claim 27, wherein, The outer diameter of the stator is selected from the following group: 40mm, 45mm, 50mm, 60mm, 70mm and 80mm.

31. The motor assembly of claim 27, wherein, The width of the plurality of stator teeth is approximately 6.00 mm to 7.00 mm.

32. The motor assembly of claim 27, wherein, The height of the plurality of stator teeth is approximately 5.50 mm to 7.00 mm.

33. The motor assembly of claim 27, wherein the thickness of the outer wall is less than or equal to about 3.1 mm.

34. The motor assembly of claim 27, wherein, The thickness of the outer wall is greater than or approximately 1.00 mm.

35. The motor assembly of claim 27, wherein, The stator includes a plurality of slots formed by the outer wall and the plurality of stator teeth.

36. The motor assembly of claim 35, wherein the area of ​​each of the plurality of slots is at least about 80.00 mm². 2 The outer diameter of the stator is approximately 50 mm.

37. The motor assembly of claim 27, wherein, The stator includes a stator insulator covering the stator lamination stack, the stator insulator comprising an outer portion and an inner portion.

38. The motor assembly of claim 37, wherein, The thickness of the outer portion is less than approximately 0.25 mm.

39. The motor assembly of claim 37, wherein, The thickness of the internal portion is less than approximately 0.20 mm.

40. The motor assembly of claim 27, wherein the ratio of the stator tooth width to the outer wall thickness of the stator is approximately 1.

9.

41. An electric tool, comprising: case; and A motor, supported within the housing, comprising a stator and a rotor, wherein the rotor is disposed within the stator. The stator includes a stator lamination stack, a plurality of stator teeth, and a plurality of stator coils. The stator lamination stack includes an outer wall, the length of which is approximately 6.00 mm to 15.00 mm. The plurality of stator teeth extend radially inward from the outer wall. The rotor, including the rotor lamination stack, comprises multiple magnet slots and multiple magnets, wherein the length of the rotor lamination stack is approximately 6.00 mm to 15.00 mm, and each of the multiple magnets is disposed within a magnet slot among the multiple magnet slots. The ratio of the stator tooth width to the outer wall thickness of the stator is approximately 1.8 to 2.

5.

42. The power tool of claim 41, wherein the outer diameter of the stator is approximately 50 mm.

43. The power tool of claim 41, wherein the outer diameter of the stator is selected from the group consisting of 40 mm, 45 mm, 60 mm, 70 mm and 80 mm.

44. The power tool as claimed in claim 41, wherein, The width of the plurality of stator teeth is approximately 6.00 mm to 7.00 mm.

45. The power tool as claimed in claim 41, wherein, The height of the plurality of stator teeth is approximately 5.50 mm to 7.00 mm.

46. ​​The power tool of claim 41, wherein the thickness of the outer wall is less than or equal to about 3.10 mm.

47. The power tool of claim 46, wherein the thickness of the outer wall is greater than about 1.00 mm.

48. The power tool as claimed in claim 41, wherein, The stator includes a plurality of slots formed by the outer wall and the plurality of stator teeth.

49. The power tool of claim 48, wherein the area of ​​each of the plurality of slots is at least about 80.00 mm². 2 The outer diameter of the stator is approximately 50 mm.

50. The power tool as claimed in claim 41, wherein, The stator includes a stator insulator covering the stator lamination stack, the stator insulator comprising an outer portion and an inner portion.

51. The power tool as claimed in claim 50, wherein, The thickness of the outer portion is less than approximately 0.25 mm.

52. The power tool as claimed in claim 50, wherein, The thickness of the internal portion is less than approximately 0.20 mm.

53. The power tool of claim 41, wherein the width of the plurality of magnets is approximately 3.00 mm to 4.00 mm.

54. The power tool of claim 41, wherein the length of the plurality of magnets is approximately 6.00 mm to 15.00 mm.

55. The power tool as claimed in claim 41, wherein, The ratio of the stator tooth width to the stator outer wall thickness is approximately 1.

9.

56. A motor assembly, comprising: Stator, the stator comprising: A stator lamination stack, the stator lamination stack including an outer wall, wherein the length of the stator lamination stack is approximately 6.0 mm to 15.00 mm. Multiple stator teeth extending radially inward from the outer wall, and Multiple stator coils; and Rotor, the rotor being disposed within the stator, the rotor comprising: A rotor lamination stack, the rotor lamination stack including a plurality of magnet slots, wherein the length of the rotor lamination stack is approximately 6.00 mm to 15.00 mm, and A plurality of magnets, wherein each of the plurality of magnets is disposed within a magnet slot in a plurality of magnet slots. The stator includes a stator insulator covering the stator lamination stack, the stator insulator comprising an outer portion and an inner portion. The thickness of the outer portion is less than about 0.25 mm, and the thickness of the inner portion is less than about 0.20 mm.

57. A motor assembly, comprising: Stator, the stator comprising: A stator lamination stack, the stator lamination stack including an outer wall, wherein the length of the stator lamination stack is approximately 6.0 mm to 15.00 mm. Multiple stator teeth extending radially inward from the outer wall, and Multiple stator coils; and Rotor, the rotor being disposed within the stator, the rotor comprising: A rotor lamination stack, the rotor lamination stack including a plurality of magnet slots, wherein the length of the rotor lamination stack is approximately 6.00 mm to 15.00 mm, and A plurality of magnets, wherein each of the plurality of magnets is disposed within a magnet slot in a plurality of magnet slots. The width of the plurality of magnets is approximately 3.00 mm to 4.00 mm, and the length of the plurality of magnets is approximately 6.00 mm to 15.00 mm.

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