Power tools including transverse FLUX motors

Abstract

A power tool including a battery pack interface and a transverse flux motor. The battery pack interface is configured to receive a removable and rechargeable battery pack. The transverse flux motor includes a stator and a rotor. The stator includes a stator core composed of soft magnetic composite material and a stator winding. The rotor is configured to rotate with respect to the stator. The rotor includes a rotor core and a plurality of permanent magnets.

Description

Attorney Docket No. 066042- 1890- WOO 1POWER TOOLS INCLUDING TRANSVERSE FLUX MOTORSRELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 686,385, filed Aug. 23, 2024, the entire content of which is incorporated herein by reference.FIELD

[0002] Embodiments described herein relate to motors for use in a power tool and / or outdoor power equipment.SUMMARY

[0003] Transverse flux motors (“TFMs”) have only been used in high torque and low speed applications, such as propulsion systems, the aerospace industry, the automotive industry, and robotics.

[0004] Transverse flux motors being used on power tools provides a number of advantages. First, transverse flux motors eliminates end-turn length of the stator windings, which allows for a reduced length of the motor and reduced winding resistance. The number of poles on a rotor in a transverse flux motor does not increase stator coil resistance, so an increased number of poles can be added to increase torque density without increasing stator coil resistance.

[0005] Power tools described herein include a battery pack interface and a transverse flux motor. The battery pack interface is configured to receive a removable and rechargeable battery pack. The transverse flux motor includes a stator and a rotor. The stator includes a stator core made of soft magnetic composite material and a stator winding. The rotor is configured to rotate with respect to the stator. The rotor includes a rotor core and a plurality of permanent magnets.

[0006] Power tools described herein include a battery pack interface configured to receive a battery pack and a transverse flux motor. The transverse flux motor includes a stator including a stator core made of soft magnetic composite material and a stator winding. The transverse flux motor also includes a rotor configured to rotate with respect to the stator. The rotor includes a rotor core and a plurality of permanent magnets. The stator winding is configured to direct magnetic flux along a magnetic flux path and direct current along a current path, the magnetic flux path being perpendicular relative to the current path.Attorney Docket No. 066042- 1890- WOO 1

[0007] Power tools described herein include a battery pack interface configured to receive a battery pack and a transverse flux motor. The transverse flux motor includes a stator including a stator core made of steel, a stator winding, and a slot configured to receive the stator winding. The transverse flux motor also includes a rotor configured to rotate with respect to the stator. The rotor includes a rotor core and a plurality of permanent magnets.

[0008] Power tools described herein include a battery pack interface configured to receive a battery pack and a transverse flux motor. The transverse flux motor includes a stator including a stator core including a plurality of laminated steel sheets. The stator core includes a first leg, a second leg, a third leg, a fourth leg, and a fifth leg, and a stator winding. The transverse flux motor also includes a rotor configured to rotate with respect to the stator. The rotor includes a rotor core and a plurality of permanent magnets.

[0009] Before any embodiments are explained in detail, it is to be understood that the embodiments are not limited in application to the details of the configurations and arrangements of components set forth in the following description or illustrated in the accompanying drawings. The embodiments are capable of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof are meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings.

[0010] Unless the context of their usage unambiguously indicates otherwise, the articles “a,” “an,” 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.” Likewise, when the terms “the” or “said” are used to refer to a noun previously introduced by the indefinite article “a” or “an,” “the” and “said” mean “at least one” or “one or more” unless the usage unambiguously indicates otherwise.

[0011] In addition, it should be understood that embodiments may include hardware, software, and electronic components or modules that, for purposes of discussion, may beAttorney Docket No. 066042- 1890- WOO 1 illustrated and described as if the majority of the components were implemented solely in hardware. However, one of ordinary skill in the art, and based on a reading of this detailed description, would recognize that, in at least one embodiment, the electronic-based aspects may be implemented in software (e.g., stored on non-transitory computer-readable medium) executable by one or more processing units, such as a microprocessor and / or application specific integrated circuits (“ASICs”). As such, it should be noted that a plurality of hardware and software based devices, as well as a plurality of different structural components, may be utilized to implement the embodiments. For example, “servers,” “computing devices,” “controllers,” “processors,” etc., described in the specification can include one or more processing units, one or more computer-readable medium modules, one or more input / output interfaces, and various connections (e.g., a system bus) connecting the components.

[0012] Relative terminology, such as, for example, “about,” “approximately,” “substantially,” etc., used in connection with a quantity or condition would be understood by those of ordinary skill to be inclusive of the stated value and has the meaning dictated by the context (e.g., the term includes at least the degree of error associated with the measurement accuracy, tolerances [e.g., manufacturing, assembly, use, etc.] associated with the particular value, etc.). Such terminology should also be considered as disclosing the range defined by the absolute values of the two endpoints. For example, the expression “from about 2 to about 4” also discloses the range “from 2 to 4”. The relative terminology may refer to plus or minus a percentage (e.g., 1%, 5%, 10%) of an indicated value.

[0013] It should be understood that although certain drawings illustrate hardware and software located within particular devices, these depictions are for illustrative purposes only. Functionality described herein as being performed by one component may be performed by multiple components in a distributed manner. Likewise, functionality performed by multiple components may be consolidated and performed by a single component. In some embodiments, the illustrated components may be combined or divided into separate software, firmware and / or hardware. For example, instead of being located within and performed by a single electronic processor, logic and processing may be distributed among multiple electronic processors. Regardless of how they are combined or divided, hardware and software components may be located on the same computing device or may be distributed among different computing devices connected by one or more networks or other suitable communication links. Similarly, aAttorney Docket No. 066042- 1890- WOO 1 component described as performing particular functionality may also perform additional functionality not described herein. For example, a device or structure that is “configured” in a certain way is configured in at least that way but may also be configured in ways that are not explicitly listed.

[0014] Accordingly, in the claims, if an apparatus, method, or system is claimed, for example, as including a controller, control unit, electronic processor, computing device, logic element, module, memory module, communication channel or network, or other element configured in a certain manner, for example, to perform multiple functions, the claim or claim element should be interpreted as meaning one or more of such elements where any one of the one or more elements is configured as claimed, for example, to make any one or more of the recited multiple functions, such that the one or more elements, as a set, perform the multiple functions collectively.

[0015] Other aspects of the embodiments will become apparent by consideration of the detailed description and accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1 illustrates a perspective view of a power tool, according to some embodiments.

[0017] FIG. 2 illustrates a block diagram of a control system of the power tool of FIG. 1, according to some embodiments.

[0018] FIG. 3 illustrates a battery pack for use with the power tool of FIG. 1, according to some embodiments.

[0019] FIG. 4 illustrates a block diagram of a control system of the battery pack of FIG. 3, according to some embodiments.

[0020] FIG. 5 illustrates a transverse flux motor in linear form, according to some embodiments.

[0021] FIG. 6 illustrates a transverse flux motor, according to some embodiments.

[0022] FIG. 7 illustrates a cross section of a transverse flux motor, according to some embodiments.Attorney Docket No. 066042- 1890- WOO 1

[0023] FIG. 8 illustrates a section of a transverse flux motor, according to some embodiments.

[0024] FIG. 9 illustrates a cross section of a transverse flux motor, according to some embodiments.

[0025] FIG. 10 illustrates a section of a transverse flux motor, according to some embodiments.

[0026] FIG. 11 illustrates a cross section of a transverse flux motor, according to some embodiments.

[0027] FIG. 12 illustrates a section of a transverse flux motor, according to some embodiments.

[0028] FIG. 13 illustrates a section of a transverse flux motor, according to some embodiments.

[0029] FIG. 14 illustrates a section of a transverse flux motor, according to some embodiments.

[0030] FIG. 15 illustrates a section of a transverse flux motor, according to some embodiments.

[0031] FIG. 16 illustrates a cross section of a transverse flux motor, according to some embodiments.

[0032] FIG. 17 illustrates a cross section of a transverse flux motor, according to some embodiments.

[0033] FIG. 18 illustrates a cross section of a transverse flux motor, according to some embodiments.DETAILED DESCRIPTION

[0034] FIG. 1 illustrates a power tool 100 including a permanent magnet motor. The power tool 100 is, for example, a hammer drill including a housing 102. The housing 102 includes a handle portion 104 and motor housing portion 106. The power tool 100 further includes an output driver 108 (illustrated as a chuck), a trigger 110, and a battery pack interface 112. The battery pack interface 112 is configured to mechanically and electrically connect to or receive aAttorney Docket No. 066042- 1890- WOO 1 power tool battery pack. Although FIG. 1 illustrates a hammer drill, in some embodiments, the components described herein are incorporated into other types of power tools including drilldrivers, impact drivers, impact wrenches, angle grinders, circular saws, reciprocating saws, plate compactors, core drills, string trimmers, leaf blowers, vacuums, and the like. In a permanent magnet motor power tool, such as power tool 100, switching elements are selectively enabled and disabled by control signals from a controller to selectively apply power from a power source (e.g., a battery pack) to drive a permanent magnet motor. In some embodiments, the power tool 100 can be any power tool including a permanent magnet motor that is configured to be operated at, for example, 20,000 rotations per minute or less.

[0035] FIG. 2 illustrates a control system 200 for the power tool 100. The control system 200 includes a controller 202. The controller 202 is electrically and / or communicatively connected to a variety of modules or components of the power tool 100. For example, the illustrated controller 202 is electrically connected to a motor 204, a battery pack 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 a plurality of switching FETs), and gate drivers 224 for driving the FET switching module 220. In some embodiments, motor 204 is a permanent magnet motor. The controller 202 includes combinations of hardware and software that are operable to, among other things, control the operation of the power tool 100, monitor the operation of the power tool 100, activate the one or more indicators 214 (e.g., an LED), etc.

[0036] The controller 202 includes a plurality of electrical and electronic components that provide power, operational control, and protection to the components and modules within the controller 202 and / or the power tool 100. For example, the controller 202 includes, among other things, a processing unit 226 (e.g., a microprocessor, a microcontroller, an electronic controller, an electronic processor, or another suitable programmable device), a memory 228, input units 230, and output units 232. The processing unit 226 includes, among other things, a control unit 234, an arithmetic logic unit (“ALU”) 236, and a plurality of registers 238, and is implemented using a known computer architecture (e.g., a modified Harvard architecture, a von Neumann architecture, etc.). The processing unit 226, the memory 228, the input units 230, and the output units 232, as well as the various modules or circuits connected to the controller 202 are connected by one or more control and / or data buses (e.g., common bus 240). The control and / orAttorney Docket No. 066042- 1890- WOO 1 data buses are shown generally in FIG. 2 for illustrative purposes. The use of one or more control and / or data buses for the interconnection between and communication among the various modules, circuits, and components would be known to a person skilled in the art in view of the embodiments described herein.

[0037] The memory 228 is a non-transitory computer readable medium and includes, for example, a program storage area and a data storage area. The program storage area and the data storage area can include combinations of different types of memory, such as a ROM, a RAM (e.g., DRAM, SDRAM, etc.), EEPROM, flash memory, a hard disk, an SD card, or other suitable magnetic, optical, physical, or electronic memory devices. The processing unit 226 is connected to the memory 228 and executes software instructions that are capable of being stored in a RAM of the memory 228 (e.g., during execution), a ROM of the memory 228 (e.g., on a generally permanent basis), or another non-transitory computer readable medium such as another memory or a disc. Software included in the implementation of the power tool 100 can be stored in the memory 228 of the controller 202. The software includes, for example, firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. The controller 202 is configured to retrieve from the memory 228 and execute, among other things, instructions related to the control processes and methods described herein. In other constructions, the controller 202 includes additional, fewer, or different components.

[0038] The battery pack interface 206 includes a combination of mechanical components (e.g., rails, grooves, latches, etc.) and electrical components (e.g., one or more terminals) configured to and operable for interfacing (e.g., mechanically, electrically, and communicatively connecting) with a battery pack. For example, power provided by a battery pack 300 (see FIG. 3) to the power tool 100 is provided through the battery pack interface 206 to the power input module 218. The power input module 218 includes combinations of active and passive components to regulate or control the power received from the battery pack 300 prior to power being provided to the controller 202. The battery pack interface 206 also supplies power to the FET switching module 220 to be switched by the switching FETs to selectively provide 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.Attorney Docket No. 066042- 1890- WOO 1

[0039] The sensor circuits 212 include one or more current sensors, one or more speed sensors, one or more Hall effect sensors, one or more temperature sensors, etc. The indicators 214 include, for example, one or more light-emitting diodes (“LEDs”). The indicators 214 can be configured to display conditions of, or information associated with, the power tool 100. For example, the indicators 214 are configured to indicate measured electrical characteristics of the power tool 100, the status of the power tool, the status the motor 204, etc. The user input module 216 is operably coupled to the controller 202 to, for example, select a forward mode of operation or a reverse mode of operation, a torque and / or speed setting for the power tool 100 (e.g., using torque and / or speed switches), etc. In some embodiments, the user input module 216 includes a combination of digital and analog input or output devices required to achieve a desired level of operation for the power tool 100, such as one or more knobs, one or more dials, one or more switches, one or more buttons, etc.

[0040] FIG. 3 illustrates a battery pack 300. 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.

[0041] FIG. 4 illustrates a control system for the battery pack 300. The control system includes a controller 400. The controller 400 is electrically and / or communicatively connected to a variety of modules or components of the battery pack 300. For example, the illustrated controller 400 is connected to one or more battery cells 402 and an interface 404 (e g., the interface portion 304 of the battery pack 300 illustrated in FIG. 3). 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 combinations of hardware and software that are operable to, among other things, control the operation of the battery pack 300, monitor a condition of the battery pack 300, enable or disable charging of the battery pack 300, enable or disable discharging of the battery pack 300, etc.

[0042] The controller 400 includes a plurality of electrical and electronic components that provide power, operational control, and protection to the components and modules within the controller 400 and / or the battery pack 300. For example, the controller 400 includes, among other things, a processing unit 412 (e.g., a microprocessor, a microcontroller, an electronicAttorney Docket No. 066042- 1890- WOO 1 processor, an electronic controller, or another suitable programmable device), a memory 414, input units 416, and output units 418. The processing unit 412 includes, among other things, a control unit 420, an ALU 422, and a plurality of registers 424, and is implemented using a known computer architecture (e.g., a modified Harvard architecture, a von Neumann architecture, etc.). The processing unit 412, the memory 414, the input units 416, and the output units 418, as well as the various modules or circuits connected to the controller 400 are connected by one or more control and / or data buses (e.g., common bus 426). The control and / or data buses are shown generally in FIG. 4 for illustrative purposes. The use of one or more control and / or data buses for the interconnection between and communication among the various modules, circuits, and components would be known to a person skilled in the art in view of the embodiments described herein.

[0043] The memory 414 is a non-transitory computer readable medium and includes, for example, a program storage area and a data storage area. The program storage area and the data storage area can include combinations of different types of memory, such as a ROM, a RAM (e.g., DRAM, SDRAM, etc.), EEPROM, flash memory, a hard disk, an SD card, or other suitable magnetic, optical, physical, or electronic memory devices. The processing unit 412 is connected to the memory 414 and executes software instructions that are capable of being stored in a RAM of the memory 414 (e.g., during execution), a ROM of the memory 414 (e.g., on a generally permanent basis), or another non-transitory computer readable medium such as another memory or a disc. Software included in the implementation of the battery pack 300 can be stored in the memory 414 of the controller 400. The software includes, for example, firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. The controller 400 is configured to retrieve from the memory 414 and execute, among other things, instructions related to the control processes and methods described herein. In other constructions, the controller 400 includes additional, fewer, or different components.

[0044] The interface 404 includes a combination of mechanical components (e.g., rails, grooves, latches, etc.) and electrical components (e.g., one or more terminals) configured to and operable for interfacing (e.g., mechanically, electrically, and communicatively connecting) the battery pack 300 with another device (e.g., a power tool, a battery pack charger, etc.). For example, the interface 404 is configured to communicatively connect to the controller 400 via a communications line 428.Attorney Docket No. 066042- 1890- WOO 1

[0045] FIG. 5 illustrates a transverse flux motor 500 for use on the power tool 100. The transverse flux motor 500 is illustrated in linear form. The transverse flux motor 500 includes a plurality of stator core elements 502 configured to receive a stator winding 504. The combination of the plurality of stator core elements 502 and stator winding 504 is configured to direct flux along a magnetic flux path 506, and direct current along a current path 508. In the illustrated embodiment, the magnetic flux path 506 is confined to the y-z plane and the current path 508 in confined to the x-z plane. As a result, the plane of the magnetic flux path 506 is perpendicular to the plane of the current path 508.

[0046] FIG. 6 illustrates a transverse flux motor 600 for use in the power tool 100. The transverse flux motor 600 includes a plurality of U-shaped stator core elements 602. The U- shaped stator core elements are configured to receive a stator winding 610. The combination of stator core elements 602 and stator winding 610 is configured to direct flux along a magnetic flux path 606 and direct current along a current path 608. A rotor 614 includes a rotor core and a plurality of permanent magnets 604 positioned in two rows along a surface of the rotor 614. The plurality of permanent magnets 604 are fastened or secured (e.g., adhered) to the rotor 614. The rotor 614 is configured to rotate along the rotational axis 612. The rotor 614 is configured to rotate with respect to the plurality of U-shaped stator core elements 602 such that the U-shaped stator core elements 602 each form a plane that is radially-aligned with the rotor 614. The plane formed by the magnetic flux path 606 is perpendicular to the current path 608.

[0047] FIG. 7 illustrates a cross section of a transverse flux motor 700 for use in the power tool 100. The transverse flux motor 700 includes a plurality of U-shaped stator core elements 702. In some embodiments, the U-shaped stator core elements 702 are made of steel (e.g., steel laminations). In other embodiments, the U-shaped stator core elements 702 are made of a soft magnetic composite (“SMC”) material. The plurality of U-shaped stator core elements are configured to receive a stator winding 710. The combination of stator core elements 702 and stator winding 710 is configured to direct flux along a magnetic flux path 706. A rotor 714 includes a rotor core and a plurality of permanent magnets 704 positioned in two rows along the surface of the rotor 714. The two rows of permanent magnets 704 form magnet pairs in an axial direction of the rotor 714 with magnets of opposite polarity (i.e., one magnet with a positive polarity facing the U-shaped stator core elements 702 and one magnet with a negative polarity facing the U-shaped stator core elements 702). The plurality of permanent magnets 704 areAttorney Docket No. 066042- 1890- WOO 1 fastened or secured (e.g., adhered) to the rotor 714. The transverse flux motor 700 advantageously provides for a simplified stator design at the cost of a more complex rotor design (e.g., magnet placement) and an increased cogging torque.

[0048] FIG. 8 illustrates a section or portion of a transverse flux motor 800 for use in the power tool 100. Although only a small section of the transverse flux motor 800 is illustrated, the illustrated section of the transverse flux motor can be extrapolated to a complete transverse flux motor that can be used in the power tool 100. The transverse flux motor 800 includes a plurality of U-shaped stator core elements 802. In some embodiments, the U-shaped stator core elements 802 are made of steel (e g., steel laminations). In other embodiments, the U-shaped stator core elements 802 are made of an SMC material. The U-shaped stator core elements 802 are configured to receive a stator winding 810. A rotor 814 includes a rotor core and a plurality of permanent magnets 804 positioned in two rows along the surface of the rotor 814. The two rows of permanent magnets 804 form magnet pairs in an axial direction of the rotor 814. The plurality of permanent magnets 804 are configured as magnet stacks having a positive polarity side and a negative polarity side. The magnet pairs include magnets of opposite polarity (i.e., one magnet with a positive polarity facing the U-shaped stator core elements 802 and one magnet with a negative polarity facing the U-shaped stator core elements 802). The plurality of permanent magnets 804 are fastened or secured (e.g., adhered) to the rotor 814. In some embodiments, the plurality of permanent magnets 804 are surface mounted permanent magnets. In some embodiments, the transverse flux motor 800 is an outer rotor motor. In other embodiments, the transverse flux motor 800 is an inner rotor motor.

[0049] Each U-shaped stator core element 802 includes a first leg 816 and a second leg 818 configured radially with respect to a rotational axis of the transverse flux motor 800. Each U- shaped stator core element 802 also includes a third leg 820 configured axially with respect to the rotational axis of the transverse flux motor 800. The first leg 816, the second leg 818, and the third leg 820 are all formed in a single plane and define a U-shaped recess 822 that is configured to receive the stator winding 810. The transverse flux motor 800 advantageously provides for a simplified stator design at the cost of a more complex rotor design (e.g., magnet placement) and an increased cogging torque.Attomey Docket No. 066042- 1890- WOO 1

[0050] FIG. 9 illustrates a cross section of a transverse flux motor 900 for use in the power tool 100. The transverse flux motor 900 includes a stator core 902. Flux is directed along a magnetic flux path 906. A rotor 914 includes a rotor core and a plurality of permanent magnets 904 integrated within the rotor 914. Every other magnet within the plurality of permanent magnets 904 has the same polarity. The magnets adjacent to one another within the plurality of permanent magnets 904 are configured to create a pole pair between them. A slot 916 is configured to receive one or more stator windings.

[0051] FIG. 10 illustrates a section or portion of a claw-pole (“CP”) transverse flux motor 1000 for use in the power tool 100. Although only a small section of the transverse flux motor 1000 is illustrated, the illustrated section of the transverse flux motor can be extrapolated to a complete transverse flux motor that can be used in the power tool 100. The section of the transverse flux motor 1000 includes a plurality of stator core elements 1002 commonly referred to as a CP-core element, that are configured to receive a stator winding 1010. In some embodiments, the CP-core elements 1002 are made of steel (e.g., steel laminations). In other embodiments, the CP-core elements 1002 are made of an SMC material. A rotor 1014 includes a rotor core and a plurality of permanent magnets 1004 integrated within the rotor 1014 and radially-oriented with respect to an axis of rotation of the transverse flux motor. The plurality of permanent magnets 1004 are configured as magnet stacks having a positive polarity side and a negative polarity side. The magnet pairs include magnets of opposite polarity (i.e., one magnet with a positive polarity facing the CP-core elements 1002 and one magnet with a negative polarity facing the CP-core elements 1002). The plurality of permanent magnets 1004 are fastened or secured (e.g., adhered) to the rotor 1014. In some embodiments, the plurality of permanent magnets 1004 are surface mounted permanent magnets. In some embodiments, the transverse flux motor 1000 is an outer rotor motor. In other embodiments, the transverse flux motor 1000 is an inner rotor motor.

[0052] The CP-core element 1002 includes a first leg 1016, a second leg 1018, and a third leg 1020 configured radially with respect to a rotational axis of the transverse flux motor 1000. Each of the first leg 1016, second leg 1018, and third leg 1020 forms a plane that is separate from the other legs (e.g., parallel to the planes formed by the other legs). Accordingly, each CP- core element 1002 can be considered a three-plane element. The CP-core elements 1002 are shown as being continuous with adjacent CP-core elements 1002. As a result, a leg of one CP-Attorney Docket No. 066042- 1890- WOO 1 core element 1002 is combined with a leg of an adjacent CP-core element 1002. Each CP-core element 1002 also includes a fourth leg 1022 and a fifth leg 1024. The legs 1022, 1024 are transverse legs that connect the first leg 1016 to the second leg 1018 and the second leg 1018 to the third leg 1020. The legs 1022, 1024 are transverse in that the planes formed by the fourth leg 1022 and fifth leg 1024 intersect the planes formed by the first leg 1016, the second leg 1018, and the third leg 1020. A rectangular-shaped recess 1026 is formed and is configured to receive the stator winding 1010.

[0053] FIG. 11 illustrates a cross section of another claw-pole transverse flux motor 1100. The cross section of a transverse flux motor 1100 includes a stator core 1102 configured to receive a stator winding 1 110. A rotor 1 114 includes a rotor core and a plurality of permanent magnets 1104 that are oriented along the outer surface of the rotor 1114. Every other magnet within the plurality of permanent magnets 1104 has the same polarity. The permanent magnets adjacent to one another within the plurality of permanent magnets 1104 are configured to create a pole pair between them. A shaft 1116 extends from both sides of the rotor body in the direction of the axis rotation. The plurality of permanent magnets 1104 are fastened or secured (e.g., adhered) to the rotor 1114. In some embodiments, the plurality of permanent magnets 1104 are surface mounted permanent magnets.

[0054] FIG. 12 illustrates a section or portion of a transverse flux motor 1200 for use in the power tool 100. Although only a small section of the transverse flux motor 1200 is illustrated, the illustrated section of the transverse flux motor can be extrapolated to a complete transverse flux motor that can be used in the power tool 100. The section of the transverse flux motor 1200 includes a plurality of U-shaped stator core elements 1202 configured to receive a stator winding 1210. In some embodiments, the U-shaped stator core elements 1202 are made of steel (e.g., steel laminations). In other embodiments, the U-shaped stator core elements 1202 are made of an SMC material. A rotor 1214 includes a rotor core and a plurality of permanent magnets 1204 positioned in two rows along the surface of the rotor 1214. The two rows of permanent magnets 1204 form magnet pairs in an axial direction of the rotor 1214. The plurality of permanent magnets 1204 are configured as magnet stacks having a positive polarity side and a negative polarity side. The magnet pairs include magnets of opposite polarity (i.e., one magnet with a positive polarity facing the U-shaped stator core elements 1202 and one magnet with a negative polarity facing the U-shaped stator core elements 1202). The plurality of permanent magnetsAttorney Docket No. 066042- 1890- WOO 11204 are fastened or secured (e.g., adhered) to the rotor 1214. In some embodiments, the plurality of permanent magnets 1204 are surface mounted permanent magnets. In some embodiments, the transverse flux motor 1200 is an outer rotor motor. In other embodiments, the transverse flux motor 1200 is an inner rotor motor. An I-core 1218 is positioned adjacent to each U-shaped stator core element 1202 and provides an additional magnetic flux path. The I-core 1218 is configured as a magnetic shunt that reduces stray flux between the U-shaped stator core elements 1202.

[0055] Each U-shaped stator core element 1202 includes a first leg 1220 and a second leg 1222 configured radially with respect to a rotational axis of the transverse flux motor 1200. Each U-shaped stator core element 1202 also includes a third leg 1224 configured axially with respect to the rotational axis of the transverse flux motor 1200. The first leg 1220, the second leg 1222, and the third leg 1224 are all formed in a single plane and define a U-shaped recess 1226 that is configured to receive the stator winding 1210. The transverse flux motor 1200 advantageously provides for a simplified stator design at the cost of a more complex rotor design (e.g., magnet placement) and an increased cogging torque.

[0056] FIG. 13 illustrates a section or portion of a transverse flux motor 1300 for use in the power tool 100. Although only a small section of the transverse flux motor 1300 is illustrated, the illustrated section of the transverse flux motor can be extrapolated to a complete transverse flux motor that can be used in the power tool 100. The transverse flux motor 1300 includes a plurality of C-shaped stator core elements 1302. In some embodiments, the C-shaped stator core elements 1302 are made of steel (e.g., steel laminations). In other embodiments, the C-shaped stator core elements 1302 are made of an SMC material. The C-shaped stator core elements 1302 are configured to receive a stator winding 1310. A rotor 1314 includes a rotor core and a plurality of permanent magnets 1304 integrated within the rotor 1314 and radially-oriented with respect to an axis of rotation of the transverse flux motor. The plurality of permanent magnets 1304 are configured as magnet stacks having a positive polarity side and a negative polarity side. The magnet pairs include magnets of opposite polarity (i.e., one magnet with a positive polarity facing the core elements 1302 and one magnet with a negative polarity facing the C-shaped stator core elements 1302). The plurality of permanent magnets 1304 are fastened or secured (e.g., adhered) to the rotor 1314. In some embodiments, the plurality of permanent magnets 1304 are surface mounted permanent magnets. In some embodiments, the transverse flux motorAttorney Docket No. 066042- 1890- WOO 11300 is an outer rotor motor. In other embodiments, the transverse flux motor 1300 is an inner rotor motor.

[0057] Each C-shaped stator core element 1302 includes a first leg 1316 and a second leg 818 configured radially with respect to a rotational axis of the transverse flux motor 800. Each C-shaped stator core element 1302 also includes a third leg 1320. The leg 1320 is a transverse leg that connects the first leg 1316 to the second leg 1318. The leg 1320 is transverse in that a plane formed by the third leg 1320 intersects planes formed by the first leg 1316 and second leg 1318. A rectangular- shaped recess 1322 is formed and is configured to receive the stator winding 1310.

[0058] FIG. 14 illustrates a section or portion of a transverse flux motor 1400 for use in the power tool 100. Although only a small section of the transverse flux motor 1400 is illustrated, the illustrated section of the transverse flux motor can be extrapolated to a complete transverse flux motor that can be used in the power tool 100. The transverse flux motor 1400 includes a plurality of stator core elements 1402. In some embodiments, the stator core elements 1402 are made of steel (e.g., steel laminations). In other embodiments, the stator core elements 1402 are made of an SMC material. The stator core elements 1402 are configured to receive stator windings 1410. A rotor 1414 includes a rotor core and a plurality of permanent magnets 1404 integrated within the rotor 1414 and radially-oriented with respect to an axis of rotation of the transverse flux motor. The plurality of permanent magnets 1404 are configured as magnet stacks having a positive polarity side and a negative polarity side. The magnet pairs include magnets of opposite polarity (i.e., one magnet with a positive polarity facing the stator core elements 1402 and one magnet with a negative polarity facing the stator core elements 1402). The plurality of permanent magnets 1404 are fastened or secured (e g., adhered) to the rotor 1414. In some embodiments, the plurality of permanent magnets 1404 are surface mounted permanent magnets. In some embodiments, the transverse flux motor 1400 is an outer rotor motor. In other embodiments, the transverse flux motor 1400 is an inner rotor motor.

[0059] The stator core element 1402 includes a first leg 1416, a second leg 1418, and a third leg 1420 configured radially with respect to a rotational axis of the transverse flux motor 1400. Each of the first leg 1416, second leg 1418, and third leg 1420 forms a plane. The plane formed by the first leg 1416 and the second leg 1418 are aligned with one another. The plane formed byAttorney Docket No. 066042- 1890- WOO 1 the third leg 1420 is separate from the other legs. Accordingly, each stator core element 1402 can be considered a two-plane element. Each stator core element 1402 also includes a fourth leg 1422 and a fifth leg 1424. The legs 1422, 1424 are transverse legs that connect the first leg 1416 to the third leg 1020 and the second leg 1418 to the third leg 1420. The legs 1422, 1424 are transverse in that planes formed by the fourth leg 1422 and fifth leg 1424 intersect the planes formed by the first leg 1416, the second leg 1418, and the third leg 1420. A split recess 1426 is formed and is configured to receive the stator windings 1410.

[0060] FIG. 15 illustrates a section or portion of a transverse flux motor 1500 for use in the power tool 100. Although only a small section of the transverse flux motor 1500 is illustrated, the illustrated section of the transverse flux motor can be extrapolated to a complete transverse flux motor that can be used in the power tool 100. The transverse flux motor 1500 includes a plurality of stator core elements 1502. In some embodiments, the stator core elements 1502 are made of steel (e.g., steel laminations). In other embodiments, the stator core elements 1502 are made of an SMC material. The stator core elements 1502 are configured to receive a stator winding 1510. A rotor 1514 includes a rotor core and a plurality of permanent magnets 1504 positioned in a row along the surface of the rotor 1514. The plurality of permanent magnets 1504 are configured as magnet stacks having a positive polarity side and a negative polarity side. The magnet pairs include magnets of opposite polarity (i.e., one magnet with a positive polarity facing the stator core elements 1502 and one magnet with a negative polarity facing the stator core elements 1502). The plurality of permanent magnets 1504 are fastened or secured (e.g., adhered) to the rotor 1514. In some embodiments, the plurality of permanent magnets 1504 are surface mounted permanent magnets. In some embodiments, the transverse flux motor 1500 is an outer rotor motor. In other embodiments, the transverse flux motor 1500 is an inner rotor motor.

[0061] Each stator core element 1502 includes a first leg 1516 and a second leg 1518 configured radially with respect to a rotational axis of the transverse flux motor 1500. Each stator core element 1502 also includes a third leg 1520 configured axially with respect to the rotational axis of the transverse flux motor 1500. Each stator core element 1502 also includes a fourth leg 1522 and a fifth leg 1524. The fourth leg 1522 extends toward the second leg 1518 but ends before reaching the second leg 1518, creating a gap 1526 in the stator core element 1502 below the stator winding 1510. The fifth leg 1524 extends axially down toward theAttorney Docket No. 066042- 1890- WOO 1 plurality of permanent magnets 1504. The first leg 1516, the second leg 1518, the third leg 1520, the fourth leg 1522, and the fifth leg 1524 are all formed in a single plane and define a rectangular recess 1528 that is configured to receive the stator winding 1510.

[0062] FIG. 16 illustrates a section or portion of a transverse flux motor 1600 for use in the power tool 100. Although only a small section of the transverse flux motor 1600 is illustrated, the illustrated section of the transverse flux motor can be extrapolated to a complete transverse flux motor that can be used in the power tool 100. The transverse flux motor 1600 includes a plurality of sub-assemblies 1605 that are oriented along an axis of rotation of the transverse flux motor 1600 and a plurality of sub-assemblies 1610 that are oriented along an axis perpendicular or radial to the axis of rotation of the transverse flux motor 1600. In some embodiments, the sub-assemblies 1605, 1610 are two-dimensional sub-assemblies (e.g., laminations). The subassemblies 1605, 1610 are configured to provide a path for both a radial flux and an axial flux. A stator winding 1615 is received by the sub-assemblies 1605, 1610. The sub-assemblies can be stacked to form a three-dimensional assembly of laminated electrical steel. The sub-assemblies 1605, 1610 can be used with any of the transverse flux motors described herein.

[0063] FIG. 17 illustrates a section or portion of a transverse flux motor 1700 for use in the power tool 100. Although only a small section of the transverse flux motor 1700 is illustrated, the illustrated section of the transverse flux motor can be extrapolated to a complete transverse flux motor that can be used in the power tool 100. A plurality of laminated steel sheets 1705 is stacked axially along an axis of rotation of the transverse flux motor 1700. The plurality of laminated steel sheets 1705 is provided on both sides of a stator winding 1710 and are configured to receive the stator winding 1710. A layer of SMC 1715 is configured to separate the plurality of laminated steel sheets 1705 on either side of the stator winding 1710. The layer of SMC 1715 is configured to provide support for the stator winding 1710. The laminated steel sheets 1705 and layer of SMC 1715 can be used with any of the transverse flux motors described herein.

[0064] FIG. 18 illustrates a section or portion of a transverse flux motor 1800 for use in the power tool 100. Although only a small section of the transverse flux motor 1800 is illustrated, the illustrated section of the transverse flux motor can be extrapolated to a complete transverse flux motor that can be used in the power tool 100. A plurality of laminated steel sheets 1805 is stacked radially with respect to an axis of rotation of the transverse flux motor 1800. TheAttorney Docket No. 066042- 1890- WOO 1 laminated steel sheets 1805 are bent and stacked on one another to receive a stator winding 1810. The laminated steel sheets 1805 can be used with any of the transverse flux motors described herein.REPRESENTATIVE FEATURES

[0065] Representative features are set out in the following clauses, which stand alone or may be combined, in any combination, with one or more features disclosed in the text and / or drawings of the specification.

[0066] Clause 1. A power tool comprising: a battery pack interface configured to receive a battery pack; and a transverse flux motor including: a stator including: a stator core made of soft magnetic composite material, and a stator winding, and a rotor configured to rotate with respect to the stator, the rotor including: a rotor core, and a plurality of permanent magnets, wherein a combination of the stator core and the stator winding is configured to direct flux along a magnetic flux path and direct current along a current path, the magnetic flux path being perpendicular relative to the current path.

[0067] Clause 2. The power tool of clause 1, wherein the stator core further includes: a first leg and a second leg positioned radially to a rotational axis, and a third leg positioned axially to the rotational axis, wherein the third leg is configured to connect the first leg and the second leg to form a U-shaped recess.

[0068] Clause 3. The power tool of clause 2, further comprising; a magnetic shunt configured to reduce stray flux between the first leg, the second leg and the third leg, wherein the magnetic shunt provides an additional magnetic flux path.

[0069] Clause 4. The power tool of clause 2, wherein the plurality of permanent magnets is arranged in two rows of magnet pairs arranged in an axial direction of the rotor along a surface of the rotor.

[0070] Clause 5. The power tool of clause 4, wherein one magnet of each of the magnet pairs has a positive polarity facing the first leg and one magnet of each of the magnet pairs has a negative polarity facing the second leg.Attorney Docket No. 066042- 1890- WOO 1

[0071] Clause 6. The power tool of clause 4, wherein one magnet of each of the magnet pairs has a positive polarity facing the second leg and one magnet of each of the magnet pairs has a negative polarity facing the second leg.

[0072] Clause 7. The power tool of clause 1, wherein the plurality of permanent magnets is surface mounted relative to the rotor.

[0073] Clause 8. The power tool of clause 1, wherein the plurality of permanent magnets is configured as magnet stacks having a positive polarity side and a negative polarity side.

[0074] Clause 9. The power tool of clause 1, wherein every other magnet within the plurality of permanent magnets has the same polarity, and magnets of the plurality of magnets adjacent to one another within the plurality of permanent magnets are configured to create a pole pair.

[0075] Clause 10. A power tool comprising: a battery pack interface configured to receive a battery pack; and a transverse flux motor including: a stator including: a stator core made of steel, a stator winding, and a slot configured to receive the stator winding, and a rotor configured to rotate with respect to the stator, the rotor including: a rotor core, and a plurality of permanent magnets.

[0076] Clause 11. The power tool of clause 10, wherein the stator core is made of laminated steel sheets.

[0077] Clause 12. The power tool of clause 11, wherein the laminated steel sheets are bent and stacked on one another to receive the stator winding.

[0078] Clause 13. The power tool of clause 10, wherein the rotor is an outer rotor.

[0079] Clause 14. The power tool of clause 10, wherein the rotor is an inner rotor.

[0080] Clause 15. The power tool of clause 10, wherein a combination of the stator core and the stator winding is configured to direct flux along a magnetic flux path and direct current along a current path, the magnetic flux path being perpendicular relative to the current path.

[0081] Clause 16. The power tool of clause 10, wherein the slot forms a rectangular-shaped recess.Attorney Docket No. 066042- 1890- WOO 1

[0082] Clause 17. A power tool comprising: a battery pack interface configured to receive a battery pack; and a transverse flux motor including: a stator including: a stator core made of a plurality of laminated steel sheets, the stator core including a first leg, a second leg, a third leg, a fourth leg, and a fifth leg, and a stator winding, and a rotor configured to rotate with respect to the stator, the rotor including: a rotor core, and a plurality of permanent magnets.

[0083] Clause 18. The power tool of clause 17, wherein the plurality of permanent magnets is integrated into the rotor.

[0084] Clause 19. The power tool of clause 17, wherein the first leg, the second leg, and the third leg are configured radially relative to a rotational axis of the rotor.

[0085] Clause 20. The power tool of clause 19, wherein the fourth leg, the fifth leg, and the sixth leg are transverse legs that connect the first leg to the second leg and the second leg to the third leg.

[0086] Clause 21. The power tool of clause 19, wherein the fourth leg, fifth leg, and sixth leg are transverse legs that connect the first leg to the third leg and the second leg to the third leg.

[0087] Clause 22. The power tool of clause 17, wherein the stator further includes: a split recess.

[0088] Clause 23. The power tool of clause 17, wherein a layer of the soft magnetic composite material is configured to separate the plurality of laminated steel sheets on either side of the stator winding and configured to provide support for the stator winding.

[0089] Clause 24. The power tool of clause 17, wherein the stator winding is configured to provide a radial flux path and an axial flux path.

[0090] Clause 25. The power tool of clause 17, wherein the fourth leg extends toward the second leg and ends before reaching the second leg, creating a gap below the stator winding, and wherein the fifth leg extends axially down toward the plurality of permanent magnets.

[0091] Thus, embodiments described herein provide, among other things, power tools including transverse flux motors. Various features and advantages are set forth in the following claims.

Claims

Attorney Docket No. 066042- 1890- WOO 1CLAIMSWe claim:

1. A power tool comprising: a battery pack interface configured to receive a battery pack; and a transverse flux motor including: a stator including: a stator core made of soft magnetic composite material, and a stator winding, and a rotor configured to rotate with respect to the stator, the rotor including: a rotor core, and a plurality of permanent magnets, wherein the stator core and the stator winding are configured to direct magnetic flux along a magnetic flux path and direct current along a current path, the magnetic flux path being perpendicular relative to the current path.

2. The power tool of claim 1, wherein the stator core further includes: a first leg and a second leg positioned radially to a rotational axis; and a third leg positioned axially to the rotational axis, wherein the third leg is configured to connect the first leg and the second leg to form a U-shaped recess.

3. The power tool of claim 2, further comprising; a magnetic shunt configured to reduce stray flux between the first leg, the second leg and the third leg, wherein the magnetic shunt provides an additional magnetic flux path.

4. The power tool of claim 2, wherein the plurality of permanent magnets is arranged in two rows of magnet pairs arranged in an axial direction of the rotor along a surface of the rotor.

5. The power tool of claim 4, wherein one magnet of each of the magnet pairs has a positive polarity facing the first leg and one magnet of each of the magnet pairs has a negative polarity facing the second leg.Attorney Docket No. 066042- 1890- WOO 16. The power tool of claim 4, wherein one magnet of each of the magnet pairs has a positive polarity facing the second leg and one magnet of each of the magnet pairs has a negative polarity facing the second leg.

7. The power tool of claim 1, wherein the plurality of permanent magnets is surface mounted relative to the rotor.

8. The power tool of claim 1, wherein the plurality of permanent magnets is configured as magnet stacks having a positive polarity side and a negative polarity side.

9. The power tool of claim 1, wherein every other magnet within the plurality of permanent magnets has a same polarity, and magnets of the plurality of permanent magnets adjacent to one another within the plurality of permanent magnets are configured to create a pole pair.

10. A power tool compri sing : a battery pack interface configured to receive a battery pack; and a transverse flux motor including: a stator including: a stator core made of steel, a stator winding, and a slot configured to receive the stator winding, and a rotor configured to rotate with respect to the stator, the rotor including: a rotor core, and a plurality of permanent magnets.

11. The power tool of claim 10, wherein the stator core includes a plurality of laminated steel sheets.

12. The power tool of claim 11, wherein the plurality of laminated steel sheets are bent and stacked on one another to receive the stator winding.Attorney Docket No. 066042- 1890- WOO 113. The power tool of claim 10, wherein the rotor is an outer rotor.

14. The power tool of claim 10, wherein the rotor is an inner rotor.

15. The power tool of claim 10, wherein the stator core and the stator winding are configured to direct magnetic flux along a magnetic flux path and direct current along a current path, the magnetic flux path being perpendicular relative to the current path.

16. The power tool of claim 10, wherein the slot forms a rectangular-shaped recess.

17. A power tool compri sing : a battery pack interface configured to receive a battery pack; and a transverse flux motor including: a stator including: a stator core including a plurality of laminated steel sheets, the stator core including a first leg, a second leg, a third leg, a fourth leg, and a fifth leg, and a stator winding, and a rotor configured to rotate with respect to the stator, the rotor including: a rotor core, and a plurality of permanent magnets.

18. The power tool of claim 17, wherein the plurality of permanent magnets is integrated into the rotor.

19. The power tool of claim 17, wherein the first leg, the second leg, and the third leg are configured radially relative to a rotational axis of the rotor.

20. The power tool of claim 19, wherein the fourth leg and the fifth leg are transverse legs that connect the first leg to the second leg and the second leg to the third leg.Attorney Docket No. 066042- 1890- WOO 121 . The power tool of claim 19, wherein the fourth leg and the fifth leg are transverse legs that connect the first leg to the third leg and the second leg to the third leg.

22. The power tool of claim 17, wherein the stator further includes: a split recess.

23. The power tool of claim 17, wherein a layer of soft magnetic composite material is configured to separate the plurality of laminated steel sheets on either side of the stator winding and configured to provide support for the stator winding.

24. The power tool of claim 17, wherein the stator winding is configured to provide a radial flux path and an axial flux path.

25. The power tool of claim 17, wherein the fourth leg extends toward the second leg and ends before reaching the second leg, creating a gap below the stator winding, and wherein the fifth leg extends axially down toward the plurality of permanent magnets.

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