Patent Description:
The present disclosure relates to power tools. More specifically, the present disclosure relates to a power tool including an input control device on a top portion of a housing.

Some electric power tools are actuated by a user engaging a trigger. A switch may be located near the trigger to change the operating mode of the power tool. For example, the switch may have a forward positon, a reverse position, and a lock position. When the switch is in the forward position, a user actuation of the trigger causes an output spindle of the power tool to operate in a forward direction. When the switch is in the reverse position, a user actuation of the trigger causes an output spindle of the power tool to operate in a reverse direction. When the switch is in the lock position, a user actuation of the trigger has no effect. The positioning of the switch near the trigger increases the size of the handle portion of the power tool and may lead to inadvertent changes to the switch position when the user engages the trigger.

<CIT>) relates to an electric motor driven hand-held tool. According to the abstract of this document there is provided an electric motor driven hand-held tool, such as a drilling, hammering or screw driving tool having a tool housing within which is located an integrated switch unit. The switch unit includes an electronic motor control unit, a first actuator which is actuated by a manually operable power member and to which the control unit is responsive to power the motor and a second actuator which is actuated by a manually operable forward/reverse member and to which the control unit is responsive to drive the motor in a selected forward or reverse direction. The forward/reverse member is located remotely from the switch unit on a portion of the tool housing which can be seen by a user of the tool during normal operation of the tool. To facilitate this a linkage arrangement is provided for actuating the second actuator in response to a manual actuation of the forward/reverse member. The linkage is pivotally mounted on a closed end of a jam pot motor casing. The linkage comprises a central annular portion pivotally mounted on a boss formed on the motor housing, a first upwardly extending arm on which the forward/reverse lever is formed and a second downwardly extending arm which engages the second actuator.

<CIT> relates to an electric-motor-driven hand-held apparatus. According to a machine translation of the abstract of this document there is provided an electric-motor-driven hand-held apparatus has a changeover switch for the rotation direction of the motor, in addition to a mains switch. The changeover switch is physically separated from the mains switch. Provided between the changeover switch and the mains switch is a blocking device in the form of a displaceable bolt, which prevents operation of the changeover switch when the mains switch is operated.

<CIT>) relates to a hand tool machine i.e. cordless screwdriver, has pistol-shaped machine housing including main handle, and operating element attached to side of machine housing, where side of machine housing turns away toward main handle. According to a machine translation of the abstract of this document the machine has an operating unit that switches between left hand motion and right hand motion by movement of an operating element of the operating unit parallel to a tool rotational axis. The operating unit includes a protective unit, which is intended to prevent switching between the left and right hand motions during activation of a drive unit. Pistol-shaped machine housing includes a main handle. The operating element is attached to a side of the housing, where the side of the housing turns away toward the handle.

<CIT>) relates to a variable speed DC motor controller apparatus particularly adapted for control of portable-power tools. According to the abstract of this document there is provided a portable electric power tool having a DC motor for driving tool bit is controlled according to speed and torque by employing a zero displacement switch means which is coupled to the tool and operative to provide an output voltage proportional to the pressure applied to the switch means via the hand of the user. The zero displacement switch interfaces with a piezoresistive array which produces a voltage output proportional to the pressure applied to the zero displacement switch. The voltage output of the array is applied to control circuit means which are coupled to the motor and which controls the speed of the motor according to the pressure applied to the switch. There is further included motor control circuitry which operates to monitor the current through the DC motor to control the speed of the motor according to the torque imparted upon the tool bit being accommodated by the portable electric tool. This document discloses a power tool according to the preamble of claim <NUM>.

In one embodiment, a power tool is provided including the features of claim <NUM>.

In one embodiment, a method for changing an operational mode of a power tool is provided including the features of claim <NUM>.

In some embodiments of the power tools and method, the input control device is further configured to receive a plurality of actuations, and to generate the mode signal responsive to each of the plurality of actuations. Additionally, the controller is further configured to receive the mode signal from the input control device upon each actuation of the input control device, and to sequentially switch among each of the plurality of operational modes responsive to each mode signal received from the input control device.

In some embodiments of the power tools and method, a trigger is positioned on the handle portion of the housing on a side of the motor housing portion opposite the input control device.

In some embodiments of the power tools and method, the controller is configured to receive a trigger signal responsive to an actuation of the trigger and operate the motor according to the selected one of the plurality of operational modes and the trigger signal.

In some embodiments of the power tools and method, an output spindle extends from the motor housing portion, and the controller is configured to receive a trigger signal responsive to an actuation of the trigger and operate the motor to control a rotation direction of the output spindle based on the trigger signal and the selected one of the plurality of operational modes.

Other aspects of the embodiments will become apparent by consideration of the detailed description and accompanying drawings.

Before any embodiments are explained in detail, it is to be understood that the embodiments are not limited in its application to the details of the configuration and arrangement 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 within the scope as defined by the claims. 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.

In addition, it should be understood that embodiments may include hardware, software, and electronic components or modules that, for purposes of discussion, may be 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" and "computing devices" 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.

<FIG> illustrate a power tool <NUM> that includes a housing <NUM>. The housing <NUM> includes a handle portion <NUM>, a motor housing portion <NUM>, and an input control device <NUM>. The motor housing portion <NUM> houses a motor therein. The handle portion <NUM> extends away from the motor housing portion <NUM>. The input control device <NUM> is, for example, a button or a switch that is configured to control an operational mode of the power tool <NUM>. The input control device <NUM> is located on a top portion <NUM> of the housing <NUM>. More particularly, as illustrated, the input control device <NUM> is positioned on a top portion of the motor housing portion <NUM>, away from the handle portion <NUM>. For example, the illustrated input control device <NUM> is on a (top) side of the motor housing portion <NUM> opposite from a (bottom) side of the motor housing portion from which the handle portion <NUM> extends. The input control device <NUM> is located above the handle portion <NUM>, a motor of the power tool <NUM>, a trigger <NUM> of the power tool <NUM>, an output spindle <NUM> of the power tool <NUM>, a battery pack for powering the power tool <NUM>, etc. By locating the input control device <NUM> on the top portion <NUM> of the housing <NUM> and remote from or away from the handle portion <NUM>, the handle portion <NUM> can be made more compact. For example, by locating the input control device <NUM> on the top portion <NUM> of the housing <NUM>, a physical lever typically located near a trigger for a power tool can be removed to make the handle portion <NUM> of the power tool <NUM> more compact.

The input control device <NUM>, which may also be referred to as a mode selector, generates a mode signal when actuated by a user of the power tool <NUM>. The input control device <NUM>, in some embodiments, includes an electro-mechanical push button that generates a pulse in response to each actuation (e.g., depression). The button may be spring biased such that actuation momentarily depresses the button in a direction of the housing <NUM> (overcoming the biasing force of the spring) and then the biasing spring returns the button to an extended position when actuation is completed. In some embodiments, the input control device <NUM> includes a touch switch, such as a capacitance switch. The generated mode signal is configured to control an operational mode of the power tool <NUM>. The input control device <NUM> is configured to modify the operational mode of the power tool <NUM> among a motor forward mode of operation, a motor reverse mode of operation, and a locked tool mode of operation.

<FIG> illustrates a simplified block diagram of the power tool <NUM>, which includes a controller <NUM> and a power source <NUM>. The power source <NUM> provides DC power to the various components of the power tool <NUM> and may be a power tool battery pack that is rechargeable and uses, for instance, lithium ion cell technology. In some instances, the power source <NUM> may receive AC power (e.g., 120V/<NUM>) from a tool plug that is coupled to a standard wall outlet, and then filter, condition, and rectify the received power to output DC power.

The controller <NUM> is electrically and/or communicatively connected to a variety of modules or components of the power tool <NUM>. For example, the illustrated controller <NUM> is connected to one or more indicators <NUM>, a power input module <NUM>, a battery pack interface <NUM>, one or more sensors <NUM>, a user input module <NUM>, a trigger switch <NUM> (connected to a trigger <NUM>), and a FET switching bridge <NUM> (e.g., including one or more switching FETs). The controller <NUM> includes combinations of hardware and software that are operable to, among other things, control the operation of the power tool <NUM>, activate the one or more indicators <NUM> (e.g., a light emitting diode (LED)), monitor the operation of the power tool <NUM>, etc..

The controller <NUM> includes a plurality of electrical and electronic components that provide power, operational control, and protection to the components and modules within the controller <NUM> and/or the power tool <NUM>. For example, the controller <NUM> includes, among other things, a processing unit <NUM> (e.g., a microprocessor, a microcontroller, or another suitable programmable device), a memory <NUM>, input units <NUM>, and output units <NUM>. The processing unit <NUM> includes, among other things, a control unit <NUM>, an arithmetic logic unit ("ALU") <NUM>, and a plurality of registers <NUM> (shown as a group of registers in <FIG>), and is implemented using a known computer architecture (e.g., a modified Harvard architecture, a von Neumann architecture, etc.). The processing unit <NUM>, the memory <NUM>, the input units <NUM>, and the output units <NUM> as well as the various modules connected to the controller <NUM> are connected by one or more control and/or data buses (e.g., common bus <NUM>).

The memory <NUM> is a non-transitory computer readable medium that 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 read-only memory ("ROM"), random access memory ("RAM") (e.g., dynamic RAM ["DRAM"], synchronous DRAM ["SDRAM"], etc.), electrically erasable programmable read-only memory ("EEPROM"), flash memory, a hard disk, an SD card, or other suitable magnetic, optical, physical, or electronic memory devices. The processing unit <NUM> is connected to the memory <NUM> and executes software instructions that are capable of being stored in a RAM of the memory <NUM> (e.g., during execution), a ROM of the memory <NUM> (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 <NUM> can be stored in the memory <NUM> of the controller <NUM>. The controller <NUM> is configured to retrieve from memory and execute, among other things, instructions related to the control of the power tool described herein.

The indicators <NUM> include, for example, one or more light-emitting diodes ("LED"). The sensors <NUM> include, for example, one or more current sensors, one or more speed sensors, one or more Hall Effect sensors, one or more temperature sensors, etc. The battery pack interface <NUM> includes a combination of mechanical and electrical components configured to, and operable for, interfacing (e.g., mechanically, electrically, and communicatively connecting) the power tool <NUM> with the power source <NUM>. For example, power provided by a battery pack (an example of the power source <NUM>) to the power tool <NUM> is provided through the battery pack interface <NUM> to the power input module <NUM>. The power input module <NUM> includes combinations of active and passive components to regulate or control the power received from the battery pack prior to power being provided to the controller <NUM>. The battery pack interface <NUM> also supplies power to the FET switching bridge <NUM> to be switched by the switching FETs to selectively provide power to a motor <NUM>. With reference back to <FIG>, the motor <NUM> is housed within the motor housing portion <NUM> and is configured to drive the output spindle <NUM>, either via a direct drive coupling or a transmission (e.g., including planetary gears). Referring back to <FIG>, the battery pack interface <NUM> also includes, for example, a communication line <NUM> for providing a communication line or link between the controller <NUM> and a battery pack.

In some embodiments, the tool includes Hall sensors <NUM> (for example, three Hall sensors) mounted on a printed circuit board (not shown) positioned axially adjacent to the motor <NUM> at different radial positions (e.g., <NUM> degrees apart from one another). The Hall sensors <NUM> output motor feedback information, such as an indication (e.g., a pulse) each time a magnet of the rotor rotates across a face of one of the Hall sensors <NUM>. Based on the motor feedback information from the Hall sensors <NUM>, the controller <NUM> can determine the position, velocity, and acceleration of the rotor. The controller <NUM> also receives user controls from user input <NUM> and the trigger switch <NUM>. In response to the motor feedback information and user controls, the controller <NUM> transmits control signals to the FET switching bridge <NUM> to drive the motor <NUM>. In some embodiments, the power tool <NUM> may be a sensorless power tool that does not include a Hall sensor <NUM> or other position sensor to detect the position of the rotor. Rather, the rotor position may be detected based on the inductance of the motor <NUM> or the back emf generated in the motor <NUM>. Although not shown, the controller <NUM> and other components of the power tool <NUM> are electrically coupled to the power source <NUM> such that the power source <NUM> provides power thereto.

In some embodiments, the FET switching bridge <NUM> includes a switch bridge having a plurality of high side power switching elements (for example, field effect transistors (FETs)) and a plurality of low side power switching elements (for example, FETs). The controller <NUM> provides the control signals to control the high side FETs and the low side FETs to drive the motor based on the motor feedback information and user controls, as noted above. For example, in response to detecting a pull of the trigger <NUM> and the input from the user input module <NUM>, the controller <NUM> provides the control signals to selectively enable and disable the FETs (e.g., sequentially, in pairs) resulting in power from the power source <NUM> to be selectively applied to stator coils of the motor <NUM> to cause rotation of a rotor. More particularly, to drive the motor <NUM>, the controller <NUM> enables a first high side FET and first low side FET pair (e.g., by providing a voltage at a gate terminal of the FETs) for a first period of time. In response to determining that the rotor of the motor <NUM> has rotated based on a pulse from the Hall sensors <NUM>, the controller <NUM> disables the first FET pair, and enables a second high side FET and a second low side FET. In response to determining that the rotor of the motor <NUM> has rotated based on pulse(s) from the Hall sensors <NUM>, the controller <NUM> disables the second FET pair, and enables a third high side FET and a third low side FET. In response to determining that the rotor of the motor <NUM> has rotated based on further pulse(s) from the Hall sensors <NUM>, the controller <NUM> disables the third FET pair and returns to enable the first high side FET and the first low side FET. This sequence of cyclically enabling pairs of high side FET and a low side FET repeats to drive the motor <NUM>. Further, in some embodiments, the control signals include pulse width modulated (PWM) signals having a duty cycle that is set in proportion to the amount of trigger pull of the trigger <NUM>, to thereby control the speed or torque of the motor <NUM>. In some embodiments, to drive the motor in a first direction (e.g., forward), the sequence of cyclically enabling pairs of the high side FETs and the low side FETs proceeds in a first order (e.g., pair <NUM>, pair <NUM>, pair <NUM>, pair <NUM>, pair <NUM>, etc.), and to drive the motor in a second direction (e.g., reverse), the sequence of cyclically enabling pairs of the high side FETs and the low side FETs proceeds in a second order (e.g., pair <NUM>, pair <NUM>, pair <NUM>, pair <NUM>, pair <NUM>, etc.).

The user input module <NUM> is operably coupled to the controller <NUM> to select a forward mode of operation, a reverse mode of operation, or a power tool lock mode of operation for the power tool <NUM>. The user input module <NUM> includes the input control device <NUM> located on the top portion of the housing <NUM>. Each time the input control device <NUM> is actuated by a user of the power tool <NUM>, the controller <NUM> receives a mode signal from the use input module <NUM>. Each time the controller <NUM> receives that mode signal from the user input module <NUM>, the power tool <NUM> mode of operation is changed. The controller <NUM> sequentially switches among each of the forward mode of operation, the reverse mode of operation, and the power tool lock mode of operation. The power tool <NUM> includes a first mode of operation, a second mode of operation, and a third mode of operation. If the power tool <NUM> is currently operating in the first mode of operation, a mode signal from the user input module <NUM> will cause the controller <NUM> to switch to the second mode of operation. If the power tool <NUM> is currently operating in the second mode of operation, a mode signal from the user input module <NUM> will cause the controller <NUM> to switch to the third mode of operation. If the power tool <NUM> is currently operating in the third mode of operation, a mode signal from the user input module <NUM> will cause the controller <NUM> to switch to the first mode of operation.

In some embodiments, the first mode of operation is the forward mode of operation in which the controller <NUM> controls the FET switching bridge <NUM> to drive the motor <NUM> in a first (forward) direction in response to depression of the trigger <NUM> and the generation of a trigger signal. In some embodiments, the second mode of operation is the reverse mode of operation in which the controller <NUM> controls the FET switching bridge <NUM> to drive the motor <NUM> in a second (reverse) direction, which is opposite the first (forward) direction, in response to depression of the trigger <NUM>. In some embodiments, the third mode of operation is the lock mode of operation in which the controller <NUM> prevents or suppresses driving of the motor <NUM> (e.g., by sending control signals to the FET switching bridge <NUM> or by not sending control signals to the FET switching bridge <NUM>), even when the trigger signal is generated responsive to the trigger <NUM> being depressed. In other words, in the lock mode of operation, the controller <NUM> ignores user depression of the trigger <NUM> and does not drive the motor <NUM> in response to user depression of the trigger <NUM>.

In some embodiments, the indicators <NUM> include LEDs to provide an indication of the mode of the power tool <NUM> as selected by the input control device <NUM>. With reference back to <FIG>, an LED of the indicators <NUM> may be associated with each symbol (i.e., forward arrow symbol 205A, reverse arrow symbol 205B, and lock symbol 205C) shown on the input control device <NUM>. The controller <NUM> illuminates the LED associated with the current mode of operation of the power tool <NUM> (e.g., the forward arrow 205A is illuminated when in the forward mode of operation, the reverse arrow 205B is illuminating when in the reverse mode of operation, and the lock symbol 205C is illuminated when in the lock mode of operation).

<FIG> is a flow diagram of a method <NUM> of controlling an operating mode of a power tool. The method <NUM> is described with reference to the power tool <NUM> described above.

In block <NUM>, a mode signal is received in a controller <NUM> of the power tool <NUM> from an input control device <NUM> positioned on a top portion <NUM> of a housing <NUM> of the power tool <NUM> positioned above a handle portion <NUM> of the housing <NUM>. Each time a user actuates the input control device <NUM> a mode signal is received by the controller <NUM>. In some embodiments, the mode signal is a pulse signal.

In block <NUM>, the controller <NUM> selects a different one of a plurality of operational modes of the power tool <NUM> responsive to the mode signal. The operational modes include at least a forward mode and a reverse mode. The operational modes also include a lock mode of operation. Stated another way, in block <NUM>, the controller <NUM> may change a current operational mode of the tool (selected from the plurality of operational modes) to another operational mode (selected from the plurality of operational modes).

In block <NUM>, the controller <NUM> operates the motor <NUM> according to the selected operational mode. For example, in the forward mode of operation, the controller <NUM> controls the FET switching bridge <NUM> to drive the motor <NUM> in a forward direction in response to a depression of the trigger <NUM> and the generation of a trigger signal by the trigger switch <NUM>. In the reverse mode of operation, the controller <NUM> controls the FET switching bridge <NUM> to drive the motor <NUM> in a reverse direction, which is opposite the forward direction, in response to a depression of the trigger <NUM> and the generation of a trigger signal by the trigger switch <NUM>. In the lock mode of operation, the controller <NUM> prevents or suppresses driving of the motor <NUM> by not sending control signals to the FET switching bridge <NUM> even when the trigger signal is generated responsive to the trigger <NUM> being depressed. In other words, in the lock mode of operation, the controller <NUM> ignores user depression of the trigger <NUM> and does not drive the motor <NUM> in response to user depression of the trigger <NUM>.

Operation of the power tool <NUM> according to the method <NUM> of <FIG> may continue after the tool is operated in block <NUM> by remaining in block <NUM> for subsequent actuations of the trigger <NUM> in the current operational mode, or by looping back to block <NUM> responsive to another actuation of the input control device <NUM> and generation of the mode signal. In some embodiments, block <NUM> is bypassed when the input control device <NUM> is actuated a subsequent time before the trigger <NUM> is actuated. Accordingly, the controller <NUM> sequentially switches (i.e., cycles) through the operational modes each time an instance of the mode signal is received, and need not first operate the motor according to a selected mode before cycling to a next operational mode. For example, with successive actuations of the input control device <NUM>, the controller <NUM> may cycle the operational mode from forward, to reverse, to lock, back to forward, to reverse, to lock, and so forth. In other examples, a different order of operational modes is used when cycling (e.g., forward, lock, reverse, forward, lock, reverse, and so forth).

Claim 1:
A power tool (<NUM>), comprising:
a housing (<NUM>) having a handle portion (<NUM>) and a motor housing portion (<NUM>);
a motor within the motor housing portion;
a mode selector (<NUM>) located remote from the handle portion and configured to generate a mode signal in response to each actuation of the mode selector;
a first indicator (<NUM>) on the top portion of the motor housing portion;
a second indicator (<NUM>) on the top portion of the motor housing portion;
a third indicator (<NUM>) on the top portion of the motor housing portion; and
a controller (<NUM>) including an electronic processor (<NUM>) and a memory (<NUM>), characterised in that the mode selector (<NUM>) is located on a top portion (<NUM>) of the motor housing portion (<NUM>), and the memory (<NUM>) is storing instructions that, when executed by the electronic processor, configure the controller to:
receive the mode signal,
sequentially cycle to a next operational mode of a plurality of operational modes of the power tool responsive to receiving the mode signal to select one of the plurality of operational modes, the plurality of operational modes including at least a forward mode, a reverse mode, and a power tool lock mode, and
operate the motor according to the selected one of the plurality of operational modes,
illuminate the first indicator after receiving a first mode signal from the mode selector to indicate a selection of a first of the forward mode, the reverse mode, and the power tool lock mode,
illuminate the second indicator after receiving a second mode signal from the mode selector to indicate a selection of a second of the forward mode, the reverse mode, and the power tool lock mode, the second mode signal received after the first mode signal, and
illuminate the third indicator after receiving a third mode signal from the mode selector to indicate a selection of a third of the forward mode, the reverse mode, and the power tool lock mode, the third mode signal received after the second mode signal, and
illuminate the first indicator after receiving a fourth mode signal from the mode selector to indicate the selection of the first of the forward mode, the reverse mode, and the power tool lock mode, the fourth mode signal received after the third mode signal.