Systems and methods for a multi-voltage power tool system

Abstract

A power tool system includes a power tool device and a plurality of battery packs. A first battery pack includes a first number of battery cells connected in series to provide a first nominal voltage, and a second battery pack includes a second number of battery cells connected in series to provide a second nominal voltage higher than the first nominal voltage. A controller of the power tool device is to operate a motor using a first set of control variables when the first battery pack is connected to the power tool device, and to operate the motor using a second set of control variables when the second battery pack is connected to the power tool device.

Description

660114.0146692101-1002-W001 SYSTEMS AND METHODS FOR A MULTI-VOLTAGE POWER TOOL SYSTEMRELATED APPLICATIONS

[0001] This application claims priority under 35 U.S.C. § 119 to United States Provisional Patent Application No. 63 / 790,333 filed on April 17, 2025. the entire contents of which is incorporated herein by reference.BACKGROUND

[0002] Power tools can be used for a variety' of purposes such as cutting, drilling, driving, sanding, shaping, grinding, polishing, painting, heating, lighting, cleaning, gardening, and construction, among other uses. Battery-powered power tools may selectively couple to a power tool battery pack to provide power for operating such power tools.SUMMARY

[0003] In accordance with an embodiment, a power tool system includes a power tool device and a plurality of battery packs. The power tool device includes a motor, a controller, an inverter that drives the motor and is controlled by the controller, and a battery pack interface. Each of the plurality' of battery packs includes a power tool device interface configured to be received by the battery pack interface to mechanically and electrically couple the battery pack to the power tool device, and a plurality of battery cells connected in series. A first battery pack of the plurality of battery packs includes a first number of battery cells connected in series to provide a first nominal voltage, and a second battery pack of the plurality of battery packs includes a second number of battery' cells connected in series to provide a second nominal voltage higher than the first nominal voltage. The controller of the power tool device is to operate the motor using a first set of control variables when the first battery' pack is connected to the power tool device, and to operate the motor using a second set of control variables when the second battery' pack is connected to the power tool device.

[0004] In accordance with another embodiment, a power tool device includes a battery pack interface configured to receive a power tool device interface of a plurality of battery packs comprising different nominal voltages. The power tool device also includes a motor, an inverter that drives the motor, and a controller that controls the inverter. The controller includes a processor and a memory, where the processor is to execute instructions stored on the memory to operate the motor using a first set of control variables when a first battery pack of the plurality of battery' packs, having a first nominal voltage, is connected to the battery pack interface, and to operate the motor using a second set of control variables when a second batteryQBM01668595.1 1660114.0146692101-1002-W001 pack of the plurality of batten' packs, having a second nominal voltage greater than the first nominal voltage, is connected to the battery pack interface.

[0005] In accordance with yet another embodiment, a method of operating a power tool configured to receive battery packs of different nominal voltages is provided. The method includes determining, via a controller, a voltage of a battery pack connected to the power tool, and obtaining control variables from memory specific to the nominal voltage, where the memory comprises a plurality of different control variables for different voltages. The method further includes operating, by the controller, the power tool using the control variables.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the disclosure and, together with the description, sen e to explain principles of the embodiments:

[0007] FIG. 1 illustrates a power tool system according to some embodiments.

[0008] FIGS. 2A and 2B illustrate examples of power tool devices that can be implemented with the power tool system of FIG. 1.

[0009] FIG. 3 illustrates different types of power tool battery packs of the power tool system of FIG. 1

[0010] FIG. 4 illustrates an exploded view' of an example pow er tool battery' pack.

[0011] FIG. 5 illustrates a block diagram of an example power tool system according to some embodiments.

[0012] FIG. 6 illustrates a flow' chart of an example method of operation of a pow er tool of the power tool system of some embodiments.

[0013] FIG. 7 illustrates a graph comparing operation of a “medium-power” power tool using different types of battery packs.

[0014] FIG. 8 illustrates another graph comparing operation of the medium-pow er power tool using different types of battery packs.

[0015] FIG. 9 illustrates a graph comparing operation of a “high-power” pow er tool using different types of battery packs.

[0016] FIG. 10 illustrates another graph comparing operation of the high-power power tool using different ty pes of battery' packs.DETAILED DESCRIPTION

[0017] Power tool devices (e.g., power tools, power tool adapters, power supplies (e.g., inverters), lasers (e.g.. rotary lasers, point lasers), work lights), may be powered by portable battery packs. For example, some power tools use electronically commutated motors that are QBM01668595.1 2660114.0146692101-1002-W001 operated via three-phase inverters (such as three-phase H-bridge inverters). The inverter converts a DC bus voltage defined by an output voltage of the battery’ pack into an alternating voltage that always energizes a particular coil that needs to be driven to move the power tool’s motor in a required direction. Furthermore, some power tools use Field Oriented Control (FOC), where every coil is energized at the same time with a different intensity to create a rotating magnetic field in the stator of the motor. Power tools may accommodate other motor control techniques as well.

[0018] An example power tool can have a native voltage of 20 volts (V) (it’s '‘nominal voltage”), though the tool is capable of operating with a voltage range between about 16-21V. That is, the inverter of the power tool has to work in this voltage range and also has to be designed so that it withstands voltage ripples caused by the interaction of the motor and the inverter during the switching process of driving the motor. In order to keep resistive and switching losses low in an inverter, the lowest possible voltage-rated components are generally selected because the on-state resistance Rdson of semiconductor devices (e.g., MOSFETs) in the inverter decreases with the voltage rating of the component. As such, in 20V tools. 40V MOSFETs are usually used.

[0019] Resistive losses in an electrical system, such as a power tool, are proportional to the square of the current, Pioss = I2R, where R is the impedance of the system, and I is the current flowing through the system. The output power of the system is proportional to the voltage and current, Pout=VI, where V is the system voltage. Accordingly, to increase output power, a battery pack with higher current capabilities (and the same nominal voltage) can be paired with high-power tools, allowing such tools to utilize the high current that the battery’ pack can provide. However, because losses are proportional to the square of the current, every time the output power of the system is doubled, the power loss in the system is quadrupled. This power loss manifests in the form of heat generation that needs to be dissipated in order not to overheat the power tool. The heat can be dissipated by heat sinks, or the heating-up process can be delayed by adding more thermal mass (e.g. more copper volume) to the power tool. This makes a power tool more expensive, heavier, and less ergonomic. Moreover, the dissipated power loss cannot be used to do drive the motor and, thus, makes the system less efficient.

[0020] It is an aspect of the present disclosure to provide a power tool capable of utilizing a higher voltage battery’ pack to extract higher power while keeping current, and power dissipation, at the same level. Accordingly, described herein is a multi-voltage power tool system, comprising a power tool capable of operating with various power tool battery packs providing different output voltages. Such a power tool can unlock more efficient operation and QBM01668595.1 3660114.0146692101-1002-W001 less heat generation, with reduced weight and cost, while also maintaining the option for a user to operate the tool with conventional, lower- voltage battery packs.

[0021] By way of example, FIG. 1 illustrates a power tool system 100. The power tool system 100 includes a power tool device 102 and a power tool battery pack 104. The power tool battery' pack 104 is selectively coupled to the power tool device 102. Accordingly, the power tool battery pack 104 may be removed (e.g., and coupled to another power tool device) and another power tool battery pack may be coupled to the power tool device 102. The power tool device 102 is illustrated in FIG. 1 as a motorized power drill-driver. The power tool device 102 includes a housing 106 with main body 108, a handle 110, an actuator (e.g., trigger) 112, a motor-driven element (e.g., chuck) 114, and a pack interface 116. The main body 108 houses a motor (not shown in FIG. 1). The handle 110 enables a user to grip the power tool device 102. The actuator 112 is manipulatable and configured to be pulled or depressed to control operation of the power tool device 102. The motor-driven element 114 is configured to receive and secure a driving or drilling bit, and to be rotated by operation of the motor in the main body- 108 to perform a drilling or driving operation. In some embodiments, the motor can be coupled to the driving or drilling bit via a gearbox, a clutch, and / or other mechanical components. The pack interface 116 is an electro-mechanical interface for selectively receiving and coupling to a power tool battery- pack, such as, e.g., the power tool battery' pack 104. The pack interface 116 may include rails (not shown) for mechanically receiving and guiding the power tool battery pack 104 and terminals (not shown in FIG. 1) for electrically coupling to the power tool battery pack 104.

[0022] The power tool battery pack 104 (herein, battery- pack 104) includes a housing 118, latching members 120, and, optionally, a fuel gauge 122. The housing 118 houses one or more battery cells, such as cylindrical or pouch cells, and electronics (not shown in FIG. 1). The latching members 120 enable the secure latching of the battery pack 104 to the power tool device 102 (and, in particular, to the pack interface 116). By depressing the latching members 120, a user may detach the battery- pack 104 from the power tool device 102. Although the battery pack 104 and pack interface 116 are illustrated as having a sliding-type engagement, in other examples, the battery pack 104 and pack interface 116 have another form factor, such as a stem-type battery- pack that has an elongated stem that is inserted within a cavity of the pack interface 116. Additionally', although the battery- pack 104 is illustrated as a first type of battery pack, in other examples, the battery- pack 104 is of another type with a different output capacity-, as further described below.QBM01668595.1 4660114.0146692101-1002-W001

[0023] Although the power tool device 102 is illustrated in FIG. 1 as a motorized power drill-driver, in some examples, the power tool device 102 is a motorized power tool of another type or is a non-motorized power tool. More specifically, FIGS. 2A and 2B illustrate other examples of the power tool device 102, where FIG. 2A illustrates a grinder 102a and FIG. 2B illustrates a blower 102b, each of which is an example of the power tool device 102. As shown in FIG. 2A, the grinder 102a is another example of a motorized power tool and includes a housing 106a with a main body 108a, a handle 110a, an actuator 112a, a motor-driven element 114a, and a pack interface 116a. The housing 106a, main body 108a, handle 110a, actuator 112a, motor-driven element 114a, and pack interface 116a are additional examples of the housing 106, main body 108, handle 110. actuator 112, motor-driven element 114, and pack interface 116 of FIG. 1, respectively.

[0024] As shown in FIG. 2B, the blower 102b is another example of a motorized power tool. The blower 102b includes a housing 106b with a main body 108b, a handle 110b, an actuator 112b, a motor-driven element (an impeller, hidden from view inside the main body 108b), and a pack interface 116b. The housing 106b, main body 108b, handle 110b, actuator 112b, motor-driven element, and pack interface 116b are additional examples of the housing 106, main body 108, handle 110, actuator 112, motor-driven element 114, and pack interface 116 of FIG. 1, respectively. Other examples of a motorized power tool include drills, hammer drills, reciprocating saws, circular saws, drivers, impact drivers, drain snakes, power ratchets, miter saws, die grinders, mixers, grinders, sanders, nailers, table saws, worksite fans, dust extractors, and the like. The discussion of the power tool device 102 herein may similarly apply to one or more of the power tool devices 102a and 102b unless otherwise noted.

[0025] As illustrated and discussed, each of the pow er tool devices 102, 102a, and 102b is configured to selectively receive and be coupled to the battery pack 104, and other battery packs having a similar electro-mechanical interface, via the pack interface 116, 116a-b. For example, with reference to FIG. 3, a power tool system 100 is illustrated, including battery packs 104a, 104b, 104c, 104d, and 104e, each having a similar electro-mechanical interface as the battery pack 104. and a power tool 102c configured to receive any one of the battery packs 104a-104e.

[0026] More specifically, FIG. 3 illustrates a first power tool battery pack 104a, a second power tool battery pack 104b, a third pow er tool battery' pack 104c, a fourth power tool battery pack 104d, and a fifth power tool battery pack 104e, each of which is an example of the battery pack 104. Each of the batters’ packs 104a-e may have the same electro-mechanical interface as the battery pack 104 such that each is configured to be received by the pack interface 116 of a QB\101668595.1 5660114.0146692101-1002-W001 power tool device 102 (such as power tool devices 102a-102c) of the power tool system 100 to mechanically and electrically couple to the battery pack 104 to the power tool device 102. However, each of the battery packs 104a-e may have or be associated with a different output capacity and, accordingly, may be a different type of battery pack from one another. For example, the battery7pack 104a may be of a first type, the battery pack 104b may be of a second type, the battery pack 104c may be of a third type, the battery pack 104d may be of a fourth type, and the battery pack 104e may be of a fifth type. As used herein, the output capacity of a pack may refer to a maximum, minimum, and / or nominal output current (amperes), a maximum, minimum, and / or nominal output voltage (volts), a maximum, minimum, and / or nominal output power (watts), output duration limits at certain current levels, an ampere-hour capacity, a watt-capacity, and / or a combination thereof. Additionally or alternatively, the output capacity7for a particular battery pack type may be described in terms of a particular combination of anumber of cells (e.g., 5, 10, or 15 cells), a particular cell type (e.g., cylindrical roll ty pe 1, cylindrical roll ty pe 2, prismatic, pouch), demand level category' (standard or high demand as categorized by a manufacturer), and / or output level (e.g., standard or high output level as categorized by a manufacturer), among other characteristics.

[0027] Each battery pack 104a-e has a housing 118 that houses one or more battery cells. The one or more battery' cells may be of various chemistries (e.g., lithium-ion (Li-Ion), nickel cadmium (Ni-Cad), etc.), and / or may be of various forms (e.g., cylindrical, pouch, prismatic, etc.). In some examples, the first battery pack 104a has a first quantity of battery cells of a first voltage, the second battery' pack 104b has a second quantity of battery' cells (greater than the first quantity'), and the third, fourth, and fifth battery' pack 104c, 104d, 104e each have a third, fourth, and fifth quantity' of battery cells, respectively (increasingly greater than the second quantity). In some examples, by increasing the quantity of battery cells, the voltage of the battery pack increases, as further described below.

[0028] Each battery pack 104a-e includes a power tool device interface 126 configured to selectively engage and mate with the pack interface 116 of a power tool device 102 (e.g., power tool devices 102, 102a-c). For example, as shown schematically in FIG. 5, the device interface 126 can include one or more power terminals 128 and, in some cases, one or more communication terminals 130 that interface with respective power terminals 132, communication terminals 134, etc., of the pack interface 116. Although some variations may be present, the device interface 126 may be substantively the same for each of the plurality' of battery packs 104a-e such that each may engage with the pack interfaces 116 of all power tools 102 associated with the power tool system 100. Accordingly, the plurality of battery packs 104, QBU01668595.1 6660114.0146692101-1002-W001 104a-e may have a device interface 126 that corresponds to the pack interfaces 116, 116a-b shown in FIGS. 1 and 2.

[0029] In some examples, each of the battery packs 104a-e may be a battery pack manufactured by Milwaukee Tool for the Ml 8™ cordless tool system. However, in other examples, the battery pack 104 of FIG. 1 (and other packs interchangeable with the power tool device 102) may be battery packs manufactured by Milwaukee Tool for the M12™ cordless tool system or the MX FUEL™ cordless equipment system. In still further examples, the systems and technologies described herein may be used with other power tool platforms (e.g., manufactured by other power tool manufacturers) and, accordingly, the battery pack 104 of FIG. 1 (and other packs interchangeable with the power tool device 102) may be battery packs manufactured by other manufacturers.

[0030] FIG. 4 illustrates an exploded view of the battery pack 104c of FIG. 3. In the exploded view, a two-piece construction of the housing 118 is illustrated, as well as internal components including: a printed circuit board 136, ten battery' cells 138, a cell retaining structure 140, and cell terminal connector assembly 142. The illustrated battery cells 138 are cylindrical cells including terminals 144, a cell housing or case 146, and a cylindrical "jelly roll” within the cell housing 138. The jelly roll may be formed by an insulating sheet, a thin layer of an anode material, a separator layer, and a layer of a cathode material, which is then rolled up into a cylindrical shape. In some embodiments, in place of cylindrical cells, one or more prismatic cells or one or more pouch cells is provided within the battery housing 118.

[0031] The battery packs 104a, 104b, 104d, and 104e of FIG. 3, and other examples of the battery pack 104 of FIG. 1, may have a generally similar construction as the battery' pack 104c, although additional or fewer rows of cylindrical cells may be present. Further, in some embodiments, each of the battery packs 104a-e is configured to provide different nominal output voltages (e.g., 18 volts, 20 volts, a voltage between 16-24 volts, 12 volts, a voltage between 10 volts and 14 volts, 54 volts, 60 volts, 72 volts, 108 volts, 120 volts, a voltage between 50-80 volts, a voltage between 54-74 volts, etc.). For example, each battery pack 104a-e can include a set number of battery cells 138, connected in series, to achieve its respective nominal output voltage. As such, the battery pack nominal voltage is determined by the number of cells in the battery pack 104 connected in series, e g., each including an "XS, IP” configuration, where “X” is the number of battery' cells in the battery pack 104 (with “S” referring to series and “P” referring to parallel). By way of example, referring back to FIG. 3, the battery pack 104a includes five battery cells 138 in series (5S, IP), providing a nominal voltage of 20 volts. That is, in this example, each Li-Ion cell can have a nominal voltage of QBU01668595.1 7660114.0146692101-1002-W001 about 4 V and, thus, a 5S nominal voltage is 5x4 = 20V. Referring still to FIG. 3, the battery pack 104b includes six battery cells 138 in series (6S, IP), providing a nominal voltage of 24 V. The battery pack 104c includes ten battery cells 138 in series (10S, IP), providing a nominal voltage of 40 V. The battery pack 104d includes twelve battery cells 138 in series (12S, IP), providing a nominal voltage of 48 V. The battery pack 104e includes fifteen battery cells 138 in series (15 S, IP), providing a nominal voltage of 60 V. However, in other examples, other numbers of battery cells may achieve the same or different nominal voltages as those of the battery packs 104a-104e.

[0032] Each of the battery packs 104a-104e can connect the battery cells 138 in series, independently of the number of cells in a pack. Therefore, instead of parallel chains of cells (e.g., battery packs having two, three, or more parallel chains of cells, designated as 2P, 3P, etc., which permit more power through higher current capabilities), a “IP” configuration is created for all battery packs 104a-104e, while the number of the batten cells 138 connected in series changes among the different battery packs 104a-104e. By this, the output voltage of the battery pack 104a-104e changes with the number of the battery cells 138 packaged into the battery pack 104 to permit higher power output with a connected power tool 102. Thus, as noted above, by connecting, e.g., five, six, ten, twelve, or fifteen battery cells 138 in series, the pack voltage of the associated battery pack 104a-104e is a nominal 20V, 24V, 40V, 48V, and 60V, respectively, though other numbers of battery cells 138 and associated nominal voltages may be incorporated in some applications. As further described below, various electronics of the power tool 102, 102a-102ccan be designed so that the power tool 102, 102a- 102c is capable of operating from the whole voltage range the various battery' packs 104, 104a-104e can provide.

[0033] For example, referring again to FIG. 5, a simplified block diagram of an example power tool system 100, including a power tool device 102 and a power tool battery pack 104, is illustrated. As shown in FIG. 5, the power tool device 102 can include a pack interface 116 (e.g., an electro-mechanical interface for selectively receiving and coupling to the power tool battery pack 104). The power tool device 102 can further include an actuator 112 (e.g., such as atrigger, as described above), a controller 148 with a processor 150 and memory 152, a power input module 154, an inverter module 156, and a motor 158.

[0034] In some embodiments, the controller 148 can be electrically and / or communicatively connected to a variety of modules or components of the power tool device 102. For example, as shown in FIG. 5, the controller 148 is connected to the battery pack interface 116, the power input module 154, the inverter 156, and the actuator 112. The QBU01668595.1 8660114.0146692101-1002-W001 controller 148 can include combinations of hardware and software that are operable to, among other things, control operation of the power tool device 102 and / or monitor operation of the power tool device 102.

[0035] For example, the processor 150 can be configured to communicate with the memory 152 to store data and retrieve stored data. The processor 150 can be configured to receive control instructions 160 and data from the memory 152 and execute, among other things, the instructions 160. For example, the control instructions 160 may include software executable by the processor 150 to enable the controller 148 to, among other things, implement the various functions of the controller 148 described herein. The software can include, for example, firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. Thus, the controller 148, coupled with the processor 150 and the memory 152, can be configured to perform certain functions, such as any of the methods described herein. More specifically, through execution of the control instructions 160 by the processor 150, the controller 148 may perform one or more of the methods described herein.

[0036] The memory 152 can include read-only memory (ROM), random access memory (RAM), other non-transitory computer-readable media, or a combination thereof. As noted above, the memory 152 can include the instructions 160 for the processor 150 to execute. Additionally, the processor 150 can also be configured to store other data on the memory 152 including information identifying the type of power tool device 102, a unique identifier for the particular power tool, user characteristics (e.g., identity, trade type, skill level), and other information relevant to operating or maintaining the power tool device 102 (e.g., received from an external source, such as an external device or pre-programed at the time of manufacture). In some examples, the instructions 160 can include control variable sets 161a-161c comprising one or more control variables relevant to operating or maintaining the power tool device 102, where each control variable set 161a-161c is related to a particular batten' pack 104, as further described below. For example, the same general control instructions 160 can be executed regardless of the battery pack 104 connected to the power tool 102, with the only difference being the control variable set 161 used with the control instructions 160. Alternatively, in some embodiments, instructions 160 can include completely separate instruction modules, e.g., with different control logic, algorithms, and / or operational variables, related to a particular battery pack 104.

[0037] In some embodiments, the memory 152 may further include a machine learning control that, when executed by the processor 150, enables the controller 148 to function as a machine learning controller. In some other embodiments, the memory 152 may include an QBM01668595.1 9660114.0146692101-1002-W001 artificial intelligence control that, when executed by the processor 150, enables the controller 148 to function as an artificial intelligence controller. The artificial intelligence controller may include instructions for implementing one or more artificial intelligence programs, algorithms, or models such as an expert system, a rules engine, a symbolic logic, one or more knowledge graphs, and so on. As used herein, artificial intelligence control may include machine learning techniques or other rule-based or model-based decision logic, and such techniques are exemplary and non-limiting.

[0038] By way of example, the controller 148 can include machine learning logic configured to assist in selecting, modifying, or adapting control variable sets 161. The machine learning logic may be implemented as one or more trained models, including statistical models, decision trees, regression models, or neural networks, executed by the processor 150. The machine learning logic may receive input data including, but not limited to, one or more of: measured battery voltage, current draw, motor speed, motor temperature, battery pack temperature, rate of voltage sag under load, duration of operation, duty cycle characteristics, and historical operating data associated with the power tool 102 or the connected battery pack 104. The output of the machine learning logic may include one or more selection signals, weighting values, or modifier values used by the controller 148 to select among predefined control variable sets 161, interpolate between control variable sets, or adjust individual control variables within a selected control variable set, such as speed limits, current limits, torque limits, or thermal thresholds. In some embodiments, the machine learning logic may be trained using empirically collected operating data obtained from one or more power tools operating with different battery' packs, tool ty pes, and usage conditions. Training may be performed prior to deployment of the power tool or updated during operation based on accumulated operating data, subject to predefined safety constraints. In such embodiments, outputs of the machine learning logic may be subject to predefined safety limits and electrical constraints, and the controller 148 enforces absolute limits on voltage, current, speed, and temperature independent of the machine learning logic. In such embodiments, the machine learning logic may not directly generate inverter switching signals but, rather, influences motor operation through selection or modification of control variables applied by the controller 148. The machine learning logic may7perform discrete selection among predefined control profiles or continuously adjust control variables as a function of operating conditions.

[0039] Referring still to FIG. 5. the controller 148 can receive power from a connected battery pack 104, e.g.. through the pack interface 116. via the power input module 154. As noted above, the device interface 126 of the battery pack 104 can include one or more power QBU01668595.1 10660114.0146692101-1002-W001 terminals 128 and, in some cases, one or more communication terminals 130 that interface with respective power terminals 132, communication terminals 134, etc., of the pack interface 116. Notably, in some embodiments, each battery pack 104, regardless of its nominal voltage, can include the same configuration of power terminals 128 and communication terminals 130 to interface with the power terminals 132 and communication terminals 134 of the pack interface 116. The power input module 154 can include combinations of active and passive components to regulate or control the power received from the battery pack 104 prior to power being provided to the controller 148. In some embodiments, the pack interface 116 also includes a communication line 162 for providing a communication line or link between the controller 148 and the battery pack 104 (e.g., via the respective communication terminals 130, 134). For example, the controller 148 can receive information from a connected battery pack 104 (e.g., the battery pack 104 may communicate a battery pack identifier) that allows the controller 148 to determine the nominal voltage of the battery pack 104. However, in some embodiments, the controller 148 may determine the nominal voltage of the battery pack 104 through other methods, e.g., through sensors, through an artificial intelligence or machine learning program, etc.

[0040] Furthermore, the battery pack interface 116 can supply power to the inverter 156, or switching module, to selectively provide power to the motor 158. The motor 158 can be, for example, a brushless direct current (BLDC) motor. The motor 158 can be operated to drive an output, such as the motor-driven element 114 described above with respect to FIG. 1. The motor 158 can be controlled by a user using the actuator 1 12. More specifically, when the user actuates the actuator 112, the controller 148 controls the drive of the motor 158 via the inverter 156.

[0041] Referring still to FIG. 5, in one example, the inverter 156 can include an H-bridge or inverter bridge for controlling the motor 158. That is, the controller 148 can provide pulsewidth modulation (PWM) signals to the inverter 156 to control the speed and direction of the motor based on signals received from the trigger 112 (e.g., and rotor position sensors / estimators, not shown). More specifically, the inverter 156 can include six semiconductor devices (such as power metal oxide field effect transistors (MOSFETs), high-el ectron-mobility transistors (HEMTs), or other suitable devices) 164 — three high-side semiconductor devices 164 coupled between a positive batten' terminal and the motor 158 and three low-side semiconductor devices 164 coupled between a negative battery terminal and the motor 158. During operation, the controller 148 provides PWM signals to the semiconductor devices 164 to selectively activate and de-activate the semiconductor devices 164. For QBU01668595.1 11660114.0146692101-1002-W001 example, the controller 148 can include a gate driver (not shown) providing the PWM signals to the semiconductor devices 164. Furthermore, as shown in FIG. 5. to dissipate heat generated by the semiconductor devices 164, one or more heat sinks 166 can be thermally coupled to the semiconductor devices 164.

[0042] Generally, in some embodiments, the power tool 102 does not include DC-DC conversion mechanisms that adjust the voltage received from a battery pack 104 and supplied to the inverter 156. Rather, the voltage of a battery pack 104, which may be in the range of, for example, 20V up to 60V or 80V or more, is supplied to the inverter 156. To create power tools that work from a higher input-voltage battery packs, such as the 20V battery pack 104a as well as the higher voltage battery packs 104b-104e, the inverter 156 is configured to withstand higher voltages, including voltage ripples. For example, a higher-voltage inverter 156 that is capable of working up to, e.g., 60V or 80V can be made of semiconductor components (e.g. semiconductor devices 164) with a voltage rating of 80- 150V. Semiconductor devices with this voltage rating will have slightly higher on-state resistances and switching losses than their 40V counterparts (which may be used for power tools 102 configured to operate only with 20V battery packs) but, if operated from a higher voltage, the overall power loss within the inverter 156 will be less while providing the same output power to the user, and thus the power efficiency of the power tool 102 is increased. Additionally, other components of the power tool 102 may be designed for the maximum nominal voltage and / or current, such as wire terminals 132 and / or heat sinks 166 within the power tool 102.

[0043] Furthermore, a power tool 102 with a high-voltage inverter 156 can be still operated from lower voltages (e.g., using a 20V battery pack 104a), though with slightly higher losses than in the case of a power tool 102 having an inverter incorporating 40V-rated semiconductor devices. For example, due to inherent current-torque and voltage-speed characteristics of motors, operating from a lower voltage may affect the operation speed of the motor 158, though will still allow the power tool 102 to be operated by a user in a work environment, as further discussed below. In contrast, power tools 102 with a 40V inverter 156 (e.g., configured to operate only with a 20V battery pack 104a) would not be operable in a work environment with higher voltage battery packs 104b- 104e.

[0044] Accordingly, examples herein provide a power tool system 100 including a power tool 102 operable with batteiy packs 104 with a large range of voltages, such as between 20V and 60V, or between 20V and 80V, or another range. Each batter}' pack 104 can include the same power tool device interface 126 that interacts with the pack interface 116 of the power tool 102, and can include a series configuration of battery cells, where the battery pack nominal QBU01668595.1 12660114.0146692101-1002-W001 voltage is determined by the number of cells in the battery' pack 104 connected in series. As a result, no switching is needed on the battery pack 104 or through the power tool 102 to operate the power tool 102 using a particular battery pack 104 in the power tool system 100, as all battery packs 104 connect to the power tool 102 using the same interface and terminals. The power tool 102 is capable of operating across the wide voltage range of battery packs 104 in the power tool system 100 by incorporating electronics such as semiconductor devices 164, heat sinks 166, wire terminals 132, and / or other electronics designed for the maximum battery pack voltage in the power tool system 100 and maximum current (e.g., for a single chain, series battery' pack configuration). For example, for a power tool system 100 comprising a power tool 102 operable with battery' packs 104 ranging from 20V to 60V or 80V, the power tool 102 can include such electronics with a voltage rating of about 80-150V.

[0045] Furthermore, the heat sinks 166 may be selected, e.g., in terms of size and weight, in proportion to an amount of heat to be distributed. For example, heat sinks 166 may be selected in proportion to a maximum current of the power tool 102, as maximum current would result in the maximum losses and resulting heat dissipation. By way of example, current ratings for series (IP) battery packs 104 are half of two-string (2P) and a third of three-string (3P) packs. That is, a 15-cell battery pack 104 would provide the same power in a 15S, IP configuration or a 5S, 3P configuration, yet the nominal voltage in the 15S,1P configuration would be three times more, and the current would be one third of, the 5S, 3P configuration. As a specific example, if a 5S, 3P battery pack 104 is a 20V-pack capable of supplying 180A. the same cell-count battery pack 104 in 15S, IP configuration would be a 60V-pack capable of 60A current. In both cases, the power of each battery pack 104 would be 3.6kW (60V*60A or 20V*180A), yet the IP battery pack 104 has a significantly less current rating, producing less heat.

[0046] In view of the above, FIG. 6 illustrates an example method 70 of operating a power tool 102 of the power tool system 100, according to some embodiments. The method 70 can be stored as instructions 160 in memory' 152 of the controller 148, to be carried out by the processor 150. Generally, the method 70 can include determining a connected battery pack’s nominal voltage (step 172), obtaining control variables specific to the determined battery pack nominal voltage (step 174), and operating the power tool using the obtained control variables (step 176).

[0047] More specifically, step 172 includes determining a connected battery packs’ nominal voltage. As described above, the controller 148 can determine a connected battery pack’s nominal voltage by communicating with a connected battery pack 104 via the QBU01668595.1 13660114.0146692101-1002-W001 communication line 162. Alternatively or additionally, the controller 148 can determine the connected battery pack’s nominal voltage through other methods, such as with sensors or machine learning logic.

[0048] Once the nominal voltage of an attached battery pack 104 is determined, step 174 includes obtaining control variables specific to the determined nominal voltage. For example, the memory 152 can store instruction variable sets 161a-161c, with each variable set 161a-161c being associated with a respective nominal voltage. Thus, at step 174, the processor 150 can retrieve a particular control variable set 16 la-161c associated with the determined nominal voltage. By way of example, control variable set 161a may include a set of variables (e.g., in a table, list, etc.) associated with battery pack 104a, control variable set 161b can include a set of variables associated with battery pack 104b, control variable set 161c can include a set of variables associated with battery pack 104c, etc. Accordingly, while three control variable sets 161a-161c are shown and described, the memory 152 can include a plurality of control variable sets and / or a plurality of separate control instructions specific to each nominal voltage of battery packs 104 of the power tool system 100. In some embodiments, the control variable sets 16 la-161 c can include operational limits of the power tool 102 when a particular battery pack 104 is connected. Examples of operational limits include, but are not limited to, motor speed limits, current limits, operating temperature limits, torque limits, and / or others. Furthermore, in some embodiments, control variables may be individually stored as tables, lists, graphs, charts, equations, etc. in relation to or as a function of respective voltages and, as a result, the processor 150 can compile a control variable set 161 by retrieving individual control variables associated with a determined voltage. In some embodiments, the control variable set 161 is selected as a discrete profile corresponding to a nominal voltage range, or continuously adjusted as a function of a measured battery voltage.

[0049] Additionally, in some embodiments, the control variable sets 161a- 161c (or individual control variables) can be specific to a particular power tool 102. For example, “power hungry” or “high-power” power tools 102 and “energy hungry” or “high energy” power tools 102 may have different operational limits for different battery pack voltages compared to “logic hungry” or “medium-power” power tools 102 or other power tools 102 due to their higher power demands compared to such other tools 102, as further discussed below. By way of example, high-power power tools 102 can include, but are not limited to circular saws, super hawgs, cutoff saws, chain saws, large angle grinders, or other similar tools. In one non-limiting example, output power for such high-power tools may be above about l,000W in some applications. Furthermore, high-energy power tools 102 can include, but are not limited to, QBU01668595.1 14660114.0146692101-1002-W001 continuously operated tools like leaf blowers, fans, polishers, etc. Additionally, medium-power power tools 102 can include, but are not limited to, impact drivers, staplers, random orbit sanders, crimp tools, or other similar tools. In one non-limiting example, output power for such medium-power tools may be below about 500W in some applications.

[0050] Referring still to the method 170 of FIG. 6, step 176 includes operating the power tool 102 according to the control instructions. That is, the controller 148 can operate the power tool 102 according to instructions 160 using the selected control variable set 161a-161c. For example, if selected control variable set 161 includes a predetermined speed limitation, the controller 148 can operate the power tool 102 by limiting the speed of the motor 158 to the predetermined speed limitation of the control variable set 161. As another example, if the selected control variable set 161 includes a predetermined current limitation, the controller 148 can operate the power tool 102 by limiting the current of the motor 158 to the predetermined current limitation of the control variable set 161. As yet another example, if the selected control variable set 161 includes a predetermined torque limitation, the controller 148 can operate the power tool 102 by limiting the torque of the motor 158 to the predetermined torque limitation of the control variable set 161. In some embodiments, the controller 148 modifies one or more reference values within a motor control loop, including torque-producing current references, speed references, or voltage saturation limits, based on the selected control variable set 161. In some embodiments, the modified reference values are used by the controller 148 to generate pulse-width-modulated gate signals for the inverter 156. For example, control variables for a 40V battery pack 104c may include values corresponding to a maximum motor electrical speed value (co_max), a peak phase current limit (I_max), and a torque constant scaling factor (k_t), or equivalent parameters, which are applied within a field-oriented control algorithm to generate PWM duty cycles for the inverter 156.

[0051] In some embodiments, the same battery pack 104 may trigger different control variables when connected to different types of power tools 102. For example, when a 40V battery pack 104c is connected to a medium-power power tool 102, such as a drill, the controller 148 may retrieve a control variable set 161 that includes a speed limit to prevent the mechanical system from being overdriven, while permitting the full current capability of the battery pack 104c. In contrast, when the same 40V battery pack 104c is connected to a high-power power tool 102, such as a right angle drill or a circular saw, the controller 148 may retrieve a different control variable set 161 that does not include a speed limit but instead includes a higher current threshold to take advantage of the higher power demands of the tool. As another example, when a 20V battery pack 104a is connected to a medium-power power tool 102, the controller 148 QBU01668595.1 15660114.0146692101-1002-W001 may retrieve a control variable set 161 with no particular operational limits, as the battery pack 104a may be well-suited for the power demands of the tool. However, when the same 20V battery pack 104a is connected to ahigh-power power tool 102, the controller 148 may retrieve a control variable set 161 that includes a torque limit to reduce current draw from the battery pack 104a and prevent overheating, and may further include field weakening parameters to increase motor speed at the expense of some torque capability.

[0052] In some embodiments, the control variable sets 161 may also differ between tool categories in terms of thermal management parameters. For example, a high-power power tool 102 operating with a lower-voltage battery pack 104 may include a control variable set 161 with a lower operating temperature threshold that triggers a thermal protection mode earlier than a control variable set 161 for the same tool operating with a higher-voltage battery pack 104, as the lower-voltage battery pack 104 may generate more heat due to higher current draw for the same output powder. Additionally, in some embodiments, a continuously operated high-energy power tool 102, such as a blower 102b, may include a control variable set 161 for a given battery pack 104 that prioritizes runtime efficiency, such as by including a power cap or duty cycle limitation, whereas a high-power power tool 102 may include a control variable set 161 for the same battery pack 104 that prioritizes peak output power without such runtime-oriented limitations.

[0053] In some embodiments, the method 170 can further, optionally, include determining if a new battery pack 104 has been connected to the power tool 102 (step 178). For example, the method 170 can continue to loop back to step 176 by operating the powder tool 102 according to the control instructions until a new battery pack 104 is connected. If a new battery pack 104 is connected, as determined at step 178, the controller 148 returns back to step 172.

[0054] Additionally, in some embodiments, different control variable sets 161 can be selected during use of a connected battery pack 104. For example, in some embodiments, step 172 can include determining, or monitoring, a voltage of the battery pack 104 during use, and control variable sets 161 may be selected at step 174 based on the monitored voltage so that voltage changes during the discharge process of the battery pack 104 can be compensated for. In such embodiments, step 176 can continuously loop back to step 172 rather than first checking for a new- battery pack connected at step 178.

[0055] As noted above, in some examples, each of the battery packs 104a-e may be a battery pack manufactured by Milwaukee Tool for the Ml 8™ cordless tool system. As such, the battery packs 104a-e can maintain all advantages on ergonomics and entry points of theQBM01668595.1 16660114.0146692101-1002-W001 existing Ml 8™ cordless tool system, but gain the advantages of higher voltage capabilities, for example, for high-power or energy -hungry power tools 102.

[0056] FIG. 7 illustrates a graph 180 of torque versus speed for an example medium-power tool, a 20V drill, operated using a 5S, IP "‘CP” battery pack (20V nominal voltage), a 5S, 2P “XC” battery' pack (20V nominal voltage), and a 5S, 3P “HD” battery pack (20V nominal voltage), and a 5S, IP “20-MV” battery pack 104a of some embodiments (20V nominal voltage). In particular, line 182 refers to a torque-speed curve from the CP battery pack, line 184 refers to a torque-speed curve from the XC battery pack, line 186 refers to a torque-speed curve from the HD battery' pack, and line 188 refers to a torque-speed curve from the 20-MV battery pack 104a.

[0057] In this example, motor speed (in RPM) was compared at 100 in-lbs torque for each battery pack. An example application of 100 in-lbs torque for such a tool would be drilling with a 2-9 / 16 self-feed bit. As shown, medium-power power tools 102 generally do not utilize higher current and power capabilities of battery' packs with 2P or 3P configurations. That is, the CP, XC, HD, and 20-MV battery packs each provided a similar experience at 100 in-lbs torque, with the XC and HD battery packs slightly boosting application speed (by ~3% and ~7%, respectively). Thus, a medium-power multi -volt power tool 102, in accordance with some embodiments, in the form of a drill may be optimized for a 20V battery' pack 104a (e.g., 5S, IP), and the power tool 102 would have a similar performance compared to a typical 20V (5S, IP) battery pack.

[0058] FIG. 8 illustrates another graph 190 of torque versus speed for the 20V drill, operated using the 5S, IP CP battery pack (20V nominal voltage), the 5S, 2P XC battery' pack (20V nominal voltage), and the 5S, 3P HD battery pack (20V nominal voltage), as well as a 10S, IP “40-MV” battery pack 104c of some embodiments (40V nominal voltage). In particular, line 182 again refers to the torque-speed curve from the CP battery pack, line 184 again refers to the torque-speed curve from the XC battery' pack, line 186 again refers to the torque-speed curve from the HD battery pack, and line 192 refers to a torque-speed curve from the 40-MV battery pack 104c.

[0059] In this example, motor speed (in RPM) was again compared at 100 in-lbs torque for each battery pack. If unlimited, the 40-MV battery pack 104c would significantly increase motor speed compared to the 20V battery packs, as show n by line 192. Thus, such a power tool 102 can include, in control variable set 161 for 40-MV battery packs 104c, a speed limit that limits the output speed (“clipping” the speed) so that the mechanical system of the power tool 102 (e.g., gears, bearings, etc.) is not overdriven when a 40-MV battery pack 104c is connected. QBM01668595.1 17660114.0146692101-1002-W001 That is. in accordance with the method 170 of FIG. 6 described above, the power tool 102 can recognize an attached 40V battery’ pack 104c and operate the power tool 102 in accordance with an instruction module limiting the speed to a predetermined limit (shown as line 194 in FIG. 8) across the torque profile. Thus, the power tool 102 can maintain a set speed across the entire torque profile when connected to a 40V battery’ pack 104c, whereas the 20V CP, XC, and HD battery packs will cause speed to slow down as torque increases. Furthermore, in some embodiments, in accordance with the method 170 of FIG. 6 described above, the power tool 102 can recognize an attached 20V CP, XC, or HD battery pack 104 and operate the power tool 102 in accordance with an instruction module that does not include a speed limit control variable across the torque profile, as such limit would not be required.

[0060] Accordingly, for a medium-power power tool 102. such as a drill, the controller 148 of the drill can operate the power tool 102 (e.g., operate the motor 158) according to a first set of control variables (e.g., control variable set 161a) when a first battery pack, such as a 20V battery pack 104a, is connected to the power tool 102, where no speed clipping is required. Further, the controller 148 can operate the motor 158 according to a second set of control variables (e.g., control variable set 161b) when the second battery’ pack, such as a 40V battery pack 104c, is connected to the power tool 102, where speed clipping may be required.

[0061] Turning to another example, FIG. 9 illustrates a graph 200 of torque versus speed for an example high-power tool, a right angle drill (Super Hawg™), operated using a 5S, 3P HD battery pack (20V nominal voltage) and a 15S, IP "60-MV" battery pack 104e of some embodiments (60V nominal voltage). In particular, line 202 refers to atorque-speed curve from the HD battery’ pack, and line 204 refers to a torque-speed curve from the 60-MV battery’ pack 104e.

[0062] In this example, motor speed (in RPM) was compared at 600 in-lbs torque for each battery pack. As shown, for high-power power tools 102, the 60V, 60-MV battery pack 104e can have similar peak power capabilities as a 20V, 5S, 3P HD battery pack. However, the 60-MV battery' pack 104e can result in significantly less power loss than the HD battery pack because current rating in the 60-MV pack would be one-third of the current rating of the HD battery for the same output power (and Pioss = I2R). For example, for a target 1630 W output power, the 20V, 5S, 3P HD battery pack requires 1790W total input power, with 160W power loss, while the 60V, 60-MV battery’ pack 104e requires 1646W total input power, with only 16W pow er loss. This 90% decrease in power losses of the battery pack 104e compared to an HD battery back can significantly reduce the cost to manage heat dissipation on the power tool 102 during operation.QBU01668595.1 18660114.0146692101-1002-W001

[0063] FIG. 10 illustrates another graph 210 of torque versus speed for the Super Hawg™ right angle drill, operated using a 5S, 2P XC battery pack (20V nominal voltage), the 5S. 3P HD battery pack (20V nominal voltage), as well as the 15S, IP 60-MV battery pack 104e (60V nominal voltage) and a 10S, IP 40-MV battery pack 104c of some embodiments (40V nominal voltage). In particular, line 202 again refers to the torque-speed curve from the HD battery pack, line 204 again refers to the torque-speed curve from the 60-MV battery pack 104e, line 212 refers to the torque-speed curve from the XC battery pack, and line 214 refers to the torquespeed curve from the 40-MV battery pack 104c.

[0064] In this example, motor speed (in RPM) was again compared at 600 in-lbs torque for each battery pack. As shown, the XC battery pack can maintain a higher speed, but cannot maintain the torque experience. On the other hand, while the 40-MV battery pack 104c elicits a drop in speed, the battery pack 104c can still maintain the torque, allowing operation of the power tool 102. Accordingly, with the power tool system 100 of some embodiments, power tools 102 can operate regardless of the nominal voltage of the attached battery pack 104. For example, attaching a lower-voltage battery pack to a high-power power tool will still allow for tool operation. In some applications, addrtional control logic can be incorporated into the control instructions 160, with additional associated control variables 1 1, when a lower-voltage battery7pack 104 is being used. For example, by using a field weakening technique, the motor speed can be increased by sacrificing torque, to some extent, at a lower-than-ideal input voltage. Such control logic might be beneficial to improve user feel during use of the power tool 102.

[0065] According to a further example, a power tool 102 may be designed for higher-voltage and lower-current operation. As such, the power tool 102 can include a control variable set 161, e.g., for a 20V HD (5S, 3P) battery pack 104, with a current limit to prevent the tool 102 from being damaged by high current that could be drawn from such packs 104. That is, in accordance with the method 170 of FIG. 6 described above, the power tool 102 can recognize a 20V HD battery' pack 104 and operate the power tool 102 in accordance with an instruction module that includes a current limit control variable, e.g., limiting current draw to a value that is characteristic of a IP battery’ pack 104. In this example, only a third of the available current of the 20V HD battery pack 104 would be used, but the power tool 102 could still be operated using the battery' pack 104 without concern for damage caused by high current draw.

[0066] In yet another example, a power tool 102 can include a control variable set 161, e.g., for smaller, low-voltage battery pack 104, with a torque limit to prevent the battery pack 104 from overheating. That is, in accordance with the method 170 of FIG. 6 described above, QBU01668595.1 19660114.0146692101-1002-W001 the power tool 102 can recognize a smaller voltage battery pack 104 and operate the power tool 102 in accordance with an instruction module that includes a torque limit control variable, which would cause less current to be drawn from the battery pack 104 so that the pack 104 does not overheat. However, the power tool 102 can include another control variable set 161, e.g., for larger or higher-voltage battery7packs 104, without such torque limits, enabling higher torque when larger battery packs 104 are connected.

[0067] In light of the above, power tool systems are provided that include a higher and w ide input voltage range for power tools, and a series of battery7packs that can provide higher input voltage to the power tools to achieve better efficiency and performance, while keeping cost and weight low and still allowing for operation using ty pical lower-voltage battery packs. That is, such systems can include various types of power tools, such as both high-power tools and medium-power tools, where all or certain types of power tools can benefit from higher voltage battery7packs, yet all ty pes of power tools can still be operable with lower voltage battery packs. Each power tool can include control variables and / or instructions adapted for each type of battery pack, such as operational limits or other operational control variables chosen based on the battery pack nominal voltage.

[0068] Such systems can be more optimized than current systems, e g., as far as overall ergonomics, cost, weight, power, and runtime are concerned. Other systems may attempt to unlock high power, high efficiency, and high thermal endurance by decreasing the system impedance, e.g., by using more expensive materials (e.g., thicker conductors, larger current rating semiconductors, thicker PCBs, etc ), and dissipating the generated heat by adding more thermal mass and heat sinks. However, here, according to some embodiments, increasing the voltage and keeping the current low7is a quadratically more effective solution to achieve the same system performance and efficiency than increasing the current and decreasing the system impedance.

[0069] It is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of ‘‘including,” “comprising,” or “having” and variations thereof herein is 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 QBM01668595.1 20660114.0146692101-1002-W001 and indirect mountings, connections, supports, and couplings. Further, ‘‘connected'’ and “coupled” are not restricted to physical or mechanical connections or couplings.

[0070] As used herein, unless otherwise limited or defined, discussion of particular directions is provided by example only, with regard to particular embodiments or relevant illustrations. For example, discussion of “top,” “front,” or “back” features is generally intended as a description only of the orientation of such features relative to a reference frame of a particular example or illustration. Correspondingly, for example, a “top” feature may sometimes be disposed below a “bottom” feature (and so on), in some arrangements or embodiments. Further, references to particular rotational or other movements (e.g., counterclockwise rotation) is generally intended as a description only of movement relative a reference frame of a particular example of illustration.

[0071] In some embodiments, including computerized implementations of methods according to the disclosure, can be implemented as a system, method, apparatus, or article of manufacture using standard programming or engineering techniques to produce software, firmware, hardware, or any combination thereof to control a processor device (e.g., a serial or parallel processor chip, a single- or multi-core chip, a microprocessor, a field programmable gate array, any variety of combinations of a control unit, arithmetic logic unit, and processor register, and so on), a computer (e.g., a processor device operatively coupled to a memory’), or another electronically operated controller to implement aspects detailed herein. Accordingly, for example, embodiments of the disclosure can be implemented as a set of instructions, tangibly embodied on a non-transitory computer-readable media, such that a processor device can implement the instructions based upon reading the instructions from the computer-readable media. Some embodiments of the disclosure can include (or utilize) a control device such as an automation device, a computer including various computer hardware, software, firmware, and so on, consistent with the discussion below. As specific examples, a control device can include a processor, a microcontroller, a field-programmable gate array, a programmable logic controller, logic gates etc., and other typical components that are known in the art for implementation of appropriate functionality’ (e g., memory’, communication systems, power sources, user interfaces and other inputs, etc.). Also, functions performed by multiple components may be consolidated and performed by a single component. Similarly, the functions described herein as being performed by one component may be performed by multiple components in a distributed manner. Additionally, a component described as performing particular functionality may also perform additional functionality not describedQBM01668595.1 21660114.0146692101-1002-W001 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 listed.

[0072] The term “article of manufacture” as used herein is intended to encompass a computer program accessible from any computer-readable device, carrier (e.g., non-transitory signals), or media (e.g., non-transitory media). For example, computer-readable media can include but are not limited to magnetic storage devices (e.g., hard disk, floppy disk, magnetic strips, and so on), optical disks (e.g., compact disk (CD), digital versatile disk (DVD), and so on), smart cards, and flash memory devices (e.g., card, stick, and so on). Additionally it should be appreciated that a carrier wave can be employed to carry7computer-readable electronic data such as those used in transmitting and receiving electronic mail or in accessing a network such as the Internet or a local area network (LAN). Those skilled in the art will recognize that many modifications may be made to these configurations without departing from the scope or spirit of the claimed subject matter.

[0073] Certain operations of methods according to the disclosure, or of systems executing those methods, may be represented schematically in the figures or otherwise discussed herein. Unless otherwise specified or limited, representation in the figures of particular operations in particular spatial order may not necessarily require those operations to be executed in a particular sequence corresponding to the particular spatial order. Correspondingly, certain operations represented in the figures, or otherwise disclosed herein, can be executed in different orders than are expressly illustrated or described, as appropriate for particular embodiments of the disclosure. Further, in some embodiments, certain operations can be executed in parallel, including by dedicated parallel processing devices, or separate computing devices configured to interoperate as part of a large system.

[0074] As used herein in the context of computer implementation, unless otherwise specified or limited, the terms "‘component,” “system,” “module,” and the like are intended to encompass part or all of computer-related systems that include hardware, software, a combination of hardware and software, or software in execution. For example, a component may be, but is not limited to being, a processor device, a process being executed (or executable) by a processor device, an object, an executable, a thread of execution, a computer program, or a computer. By w ay of illustration, both an application running on a computer and the computer can be a component. One or more components (or system, module, and so on) may reside within a process or thread of execution, may be localized on one computer, may be distributed between two or more computers or other processor devices, or may be included within another component (or system, module, and so on).QBM01668595.1 22660114.0146692101-1002-W001

[0075] In some implementations, devices or systems disclosed herein can be utilized or installed using methods embodying aspects of the disclosure. Correspondingly, description herein of particular features, capabilities, or intended purposes of a device or system is generally intended to inherently include disclosure of a method of using such features for the intended purposes, a method of implementing such capabilities, and a method of installing disclosed (or otherwise known) components to support these purposes or capabilities. Similarly, unless otherwise indicated or limited, discussion herein of any method of manufacturing or using a particular device or system, including installing the device or system, is intended to inherently include disclosure, as embodiments of the disclosure, of the utilized features and implemented capabilities of such device or system.

[0076] As used herein, unless otherwise defined or limited, ordinal numbers are used herein for convenience of reference based generally on the order in which particular components are presented for the relevant part of the disclosure. In this regard, for example, designations such as “first,” “second,” etc., generally indicate only the order in which the relevant component is introduced for discussion and generally do not indicate or require a particular spatial arrangement, functional or structural primacy or order.

[0077] As used herein, unless otherwise defined or limited, directional terms are used for convenience of reference for discussion of particular figures or examples. For example, references to downward (or other) directions or top (or other) positions may be used to discuss aspects of a particular example or figure, but do not necessarily require similar orientation or geometry in all installations or configurations.

[0078] As used herein, unless otherwise defined or limited, the phase "and / or" used with two or more items is intended to cover the items individually and both items together. For example, a device having “a and / or b" is intended to cover: a device having a (but not b); a device having b (but not a); and a device having both a and b.

[0079] This discussion is presented to enable a person skilled in the art to make and use embodiments of the disclosure. Various modifications to the illustrated examples will be readily apparent to those skilled in the art, and the generic principles herein can be applied to other examples and applications without departing from the principles disclosed herein. Thus, embodiments of the disclosure are not intended to be limited to embodiments shown, but are to be accorded the widest scope consistent with the principles and features disclosed herein and the claims below. The following detailed description is to be read with reference to the figures, in which like elements in different figures have like reference numerals. The figures, which are not necessarily to scale, depict selected examples and are not intended to limit the scope of the QBM01668595.1 23660114.0146692101-1002-W001 disclosure. Skilled artisans will recognize the examples provided herein have many useful alternatives and fall within the scope of the disclosure.

[0080] Various features and advantages of the disclosure are set forth in the following claims.QBU01668595.1 24

Claims

660114.0146692101-1002-W001 CLAIMS1. A power tool system comprising:a power tool device comprising:a motor,a controller,an inverter that drives the motor and is controlled by the controller, and a battery pack interface; anda plurality of battery packs, each of the plurality of battery’ packs comprising:a power tool device interface configured to be received by the battery pack interface to mechanically and electrically couple the battery' pack to the power tool device, anda plurality’ of battery cells connected in series, wherein a first battery’ pack of the plurality of battery packs includes a first number of battery cells connected in series to provide a first nominal voltage, and a second battery pack of the plurality7of battery packs includes a second number of battery’ cells connected in series to provide a second nominal voltage higher than the first nominal voltage,wherein the controller of the power tool device is to determine a voltage of a battery pack connected to the battery pack interface, and to operate the motor using a first set of control variables when the first battery pack is connected to the power tool device, and to operate the motor using a second set of control variables when the second battery pack is connected to the power tool device.

2. The power tool system of claim 1, wherein the power tool device includes components rated for a highest nominal voltage of the plurality of battery' packs.

3. The power tool system of claim 2, wherein the components include semiconductor devices of the inverter.

4. The power tool system of claim 2, wherein the components includes power terminals and a heat sink.

5. The power tool system of claim 1, wherein the power tool device includes a first power tool device and a second power tool device, the first power tool device having a higher power demand than the second power tool device.

6. The power tool system of claim 1, wherein the first nominal voltage is 20 volts.QBM01668595.1 25660114.0146692101-1002-W001 7. The power tool system of claim 6, wherein the second nominal voltage is one of 24 volts. 40 volts, 48 volts, and 60 volts.

8. The power tool system of claim 1, wherein the second set of control variables includes instructions to limit a speed of the motor to a predefined speed.

9. A power tool device comprising:a battery pack interface configured to receive a power tool device interface of a plurality of battery packs comprising different nominal voltages;a motor;an inverter that drives the motor; anda controller that controls the inverter, the controller comprising a processor and a memory', the processor to execute instructions stored on the memory' to:operate the motor using a first set of control variables when a first battery pack of the plurality of battery packs, having a first nominal voltage, is connected to the battery pack interface, andoperate the motor using a second set of control variables when a second battery pack of the plurality of battery packs, having a second nominal voltage greater than the first nominal voltage, is connected to the battery pack interface.

10. The power tool device of claim 9, further comprising components rated for a highest nominal voltage of the plurality of battery^ packs.

11. The power tool device of claim 10, wherein the components include semiconductor devices of the inverter.

12. The power tool device of claim 10, wherein the components includes power terminals and a heat sink.

13. The power tool device of claim 9, wherein the battery pack interface is configured to receive a power tool device interface of a plurality' of battery packs comprising different nominal voltages ranging from about 20 volts to about 60 volts.

14. The power tool device of claim 9, wherein the first set of control variables and the second set of control variables include operational limits of the motor specific to the first battery pack and the second battery pack, respectively.QBM01668595.1 26660114.0146692101-1002-W001 15. A method of operating a power tool configured to receive battery packs of different nominal voltages, the method comprising:determining, via a controller, a voltage of a battery pack connected to the power tool; obtaining control variables from memory specific to the voltage, wherein the memory comprises a plurality-' of different control variables for different voltages; andoperating, by the controller, the power tool using the control variables.

16. The method of claim 15, wherein determining the voltage of the battery pack includes obtaining a nominal voltage from the battery pack via a communication line.

17. The method of claim 15, wherein operating the power tool using the control variables includes the controller driving a motor using the control variables.

18. The method of claim 17, wherein the controller driving the motor using the control variables includes limiting a speed of the motor to a predefined speed.

19. The method of claim 15, wherein the battery pack is a first battery pack, and further comprising:determining, via the controller, a second voltage of a second battery pack connected to the power tool after the first battery pack has been removed;obtaining a second set of control variables from memory specific to the second voltage; andoperating the power tool using the second set of control variables.

20. The method of claim 15, wherein the memory comprises the plurality7of different control variables for different voltages ranging from about 20 volts to about 60 volts.QBM01668595.1 27

Images