Patent Description:
<CIT>) relates to a motor vehicle chassis sensor. According to the abstract of this document there is provided a vehicle chassis sensor assembly comprising a housing member defining a sensor cartridge slot, a rotatable shaft with a magnet and retained in a sleeve, and a rotatable arm coupled to the shaft. A sensor cartridge is mounted in the slot through the interior of a connector socket and an opening between the slot and the connector socket. A plate on the sensor cartridge covers the opening. The sensor cartridge includes a terminal header and a separate board mounted to the terminal header. The board includes the sensor. Deformable posts on the terminal header and the sensor assembly extend through respective apertures in the board and the terminal header for securing the board and the sensor cartridge to the terminal header and the sensor assembly respectively.

<CIT>) relates to a work machine in the form of a walk-behind lawn mower. According to the abstract of this document there is provided walk-behind power equipment which includes: a main body provided with a front wheel and a rear wheel; a work unit provided on the main body; a work motor that rotates a blade; a travel motor that rotates the rear wheel; a handle provided on the main body to extend rearward and upward; a posture detection means that detects a rearward tilted state of the main body in which the rear wheel is in contact with a ground and the front wheel is spaced from the ground; and a control unit that drive-controls the work motor and the travel motor, wherein when the main body is in the rearward tilted state, the control unit causes a rotational speed of the travel motor to be reduced compared to when the front wheel is in contact with the ground, or causes a rotational speed of the work motor to be reduced compared to when the front wheel is in contact with the ground.

Embodiments described herein relate to a lawnmower.

Input devices, such as a switch or trigger on a power tool, may be physically coupled to one or more electronic components, such as variable resistors, relays, and the like. Physical connections on input devices, including switches or triggers, may wear over time, thereby reducing the operational life of the tool. Thus, it would be advantageous to utilize contactless sensing device to reduce wear and increase life of the input devices and/or the power tool.

According to the invention a lawnmower described herein includes a (lawnmower) housing, one or more (cutting) blades, and a motor configured to rotate the one or more blades. The lawnmower includes a handle including a switch assembly. The switch assembly includes a contactless switch pivotable about an axis point, and a magnet located at the axis point. One or more paddles extend from the handle. Rotation of the one or more paddles causes the contactless switch to pivot about the axis point. The lawnmower includes a sensor configured to sense a variation of a magnetic field of the magnet, and a controller coupled to the motor and the sensor. The controller is configured to receive, from the sensor, a value associated with the variation of the magnetic field of the magnet (e.g., as the magnet rotates), and control the motor based on the value of the variation of the magnetic field.

The switch assembly may further include an upper housing, a lower housing and a rotator.

The magnet may be situated within the rotator.

The rotator may be coupled to the contactless switch through the upper housing.

The switch assembly may further include a printed circuit board configured to be coupled to the upper housing via a snap assembly.

The lower housing may be configured to couple to the upper housing via clamps.

The switch assembly may further include a printed circuit board.

The printed circuit board, the magnet, and the contactless switch may be configured to be coupled to the lower housing.

The lawnmower may further include a battery pack interface configured to couple with a battery pack.

The sensor may be further configured to convert the variation of the magnetic field of the magnet to an output signal.

According to another aspect of the invention, methods described herein for driving a lawnmower include detecting, with a sensor, a variation in a magnetic field from a rotation of a magnet. The rotation of the magnet is in response to pivoting of a contactless switch about an axis point. The magnet is located at the axis point. The methods also include converting, with the sensor, the variation in the magnetic field to an output signal, providing, with the sensor, the output signal to a controller, and controlling, with the controller, a motor of the lawnmower based on the output signal to rotate one or more cutting blades.

According to an aspect of the present disclosure, which is not covered by the appended claims, contactless switch assemblies for a lawnmower described herein include an upper housing, a lower housing configured to couple to the upper housing to form a switch assembly housing, and a contactless switch pivotable about an axis point. The contactless switch is external to the switch assembly housing. The contactless switch assemblies further include one or more paddles coupled to the contactless switch. The one or more paddles is configured to be rotated to pivot the contactless switch about the axis point. The contactless switch assemblies further include a magnet located at the axis point. The magnet is configured to be rotated when the one or more paddles is rotated to pivot the contactless switch about the axis point. The contactless switch assemblies further include a sensor configured to sense a variation of a magnetic field of the magnet.

The contactless switch may be bound by a first protrusion and a second protrusion.

The switch assembly may further include a printed circuit board coupled to the upper housing via a snap assembly.

The printed circuit board may extrude from the upper housing and the lower housing.

The printed circuit board, the magnet, and the contactless switch may be coupled to the lower housing.

The contactless switch assembly may be configured to be integrated into a handle of the lawnmower.

The magnet may be coupled between the printed circuit board and the contactless switch.

The printed circuit board may be internal to the switch assembly housing. Where appropriate, any of the optional features discussed herein in relation to one aspect of the invention, may be applied to another aspect of the invention.

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. 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," "computing devices," "controllers," "processors," etc., described in the specification can include one or more processing units, one or more computer-readable medium modules, one or more input/output interfaces, and various connections (e.g., a system bus) connecting the components.

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

It should be understood that although certain drawings illustrate hardware and software located within particular devices, these depictions are for illustrative purposes only. Functionality described herein as being performed by one component may be performed by multiple components in a distributed manner. Likewise, functionality performed by multiple components may be consolidated and performed by a single component. In some embodiments, the illustrated components may be combined or divided into separate software, firmware and/or hardware. For example, instead of being located within and performed by a single electronic processor, logic and processing may be distributed among multiple electronic processors. Regardless of how they are combined or divided, hardware and software components may be located on the same computing device or may be distributed among different computing devices connected by one or more networks or other suitable communication links. Similarly, a component described as performing particular functionality may also perform additional functionality not described herein. For example, a device or structure that is "configured" in a certain way is configured in at least that way but may also be configured in ways that are not explicitly listed.

<FIG> illustrates a lawnmower <NUM>, according to one embodiment. The lawnmower <NUM> includes a housing <NUM> (e.g., a lawnmower housing) and a handle <NUM> coupled to the housing <NUM> by support beams <NUM>. A motor housing <NUM> is coupled to an upper portion of the housing <NUM> and houses a motor configured to drives cutting blades <NUM>. The blades <NUM> are coupled to a lower portion of the housing <NUM>. The lawnmower <NUM> includes a plurality of wheels <NUM> driven by the motor. In some embodiments, the plurality of wheels <NUM> are driven by an auxiliary motor within the motor housing <NUM>.

<FIG> illustrate the handle <NUM>, according to some embodiments. The handle <NUM> includes a handle housing <NUM>. A first paddle 26a and a second paddle 26b (e.g., paddles <NUM>) extend from the handle housing <NUM> and act as a switch or trigger. Accordingly, operation of the first paddle 26a and the second paddle 26b may drive the motor and/or the auxiliary motor, as described in more detail below. A contactless switch assembly <NUM> is situated within the handle housing <NUM>, as shown in <FIG>.

<FIG> illustrates the contactless switch assembly <NUM> including a contactless switch <NUM>, an upper housing <NUM>, and a lower housing <NUM>. The contactless switch <NUM> is external to the upper housing <NUM> and the lower housing <NUM>. Having the contactless switch <NUM> external to the housing (i.e., upper housing <NUM> and lower housing <NUM> combined) helps prevent dust, water, and other particulates from getting into the housing. The contactless switch assembly <NUM> can also be made smaller as a result of having fewer components within the housing. As the paddles <NUM> are operated, the contactless switch <NUM> rotates about a pivot point <NUM>. In some embodiments, the contactless switch <NUM> includes an upper portion <NUM> that contacts the paddles <NUM>. Movement of the contactless switch <NUM> is bound by a first protrusion 36a and a second protrusion 36b. <FIG> provides a perspective view of the back of the contactless switch assembly <NUM> with the lower housing <NUM> removed. A printed circuit board (PCB) <NUM> is coupled to the upper housing <NUM>. A magnet <NUM> is positioned in the center of the PCB <NUM> and is coupled to the contactless switch <NUM> such that rotation of the contactless switch <NUM> results in rotation of the magnet <NUM>. The PCB <NUM> includes, for example, one or more Hall-effect sensors <NUM> (see <FIG>) in proximity to the magnet <NUM> for sensing changes in magnetic flux as the magnet <NUM> rotates. In some embodiments, the components of the PCB <NUM> are covered by a room temperature vulcanizing ("RTV") silicone or ultraviolet ("UV") glue to protect the components from dust, water, and other particulates.

<FIG> illustrates an exploded view of the contactless switch assembly <NUM>. The contactless switch <NUM> is coupled to the upper housing <NUM>. The magnet <NUM> is placed within a rotator <NUM>, which is coupled to the contactless switch <NUM> through the upper housing <NUM>. The PCB <NUM> is situated near the magnet <NUM>, rotator <NUM>, and upper housing <NUM>. In some embodiments, the magnet <NUM> includes positioning features for insert molding or press fitting. The lower housing <NUM> is situated over the PCB <NUM> and selectively couples to the upper housing <NUM> to form a switch assembly housing. As illustrated in <FIG>, the lower housing <NUM> couples to the upper housing <NUM> via clamps <NUM>. <FIG> illustrates the contactless switch assembly <NUM> for an alternative perspective. As illustrated, the PCB <NUM> may extrude from the upper housing <NUM> and the lower housing <NUM> for making electrical connections to the PCB <NUM>. <FIG> provides an additional perspective view of the contactless switch assembly <NUM>.

<FIG> illustrate perspective views of the contactless switch assembly <NUM> with the lower housing <NUM> removed. The PCB <NUM> may couple to the upper housing <NUM> via a first pin 48a, a second pin 48b, and a snap assembly <NUM>. Additionally, the PCB <NUM> may include a first corner 47a and a second corner 47b that are rounded corners.

<FIG> illustrate a variety of views of the contactless switch assembly <NUM> according to another embodiment. <FIG>, for example, provides the PCB <NUM> coupled to the lower housing <NUM>. The magnet <NUM> is coupled between the PCB <NUM> and the contactless switch <NUM> such that rotation of the contactless switch <NUM> results in rotation of the magnet <NUM>. The upper housing <NUM> then couples to the lower housing <NUM>. The lower housing <NUM> includes a pole <NUM> configured to hold the PCB <NUM>, the magnet <NUM>, and the contactless switch <NUM> in place. In the embodiment of <FIG>, the contactless switch <NUM> is internal to the combined upper housing <NUM> and lower housing <NUM>.

In some embodiments, the lawnmower <NUM> is a battery-powered lawnmower. <FIG> illustrates a battery pack <NUM> that includes a housing <NUM> and an interface portion <NUM> for connecting the battery pack <NUM> to a device, such as the lawnmower <NUM>.

A controller <NUM> for the lawnmower <NUM> is illustrated in <FIG>. The controller <NUM> is electrically and/or communicatively connected to a variety of modules or components of the lawnmower <NUM>. For example, the illustrated controller <NUM> is connected to indicators <NUM>, secondary sensor(s) <NUM> (e.g., a speed sensor, a voltage sensor, a temperature sensor, a current sensor, etc.), the paddles <NUM> (via the contactless switch <NUM> and a rotation sensor <NUM>), a power switching network <NUM>, and a power input unit <NUM>.

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 lawnmower <NUM>. For example, the controller <NUM> includes, among other things, a processing unit <NUM> (e.g., a microprocessor, an electronic processor, an electronic controller, 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 control and/or data buses are shown generally in <FIG> for illustrative purposes. The use of one or more control and/or data buses for the interconnection between and communication among the various modules and components would be known to a person skilled in the art in view of the embodiments described herein.

The memory <NUM> is a non-transitory computer readable medium and includes, for example, a program storage area and a data storage area. The program storage area and the data storage area can include combinations of different types of memory, such as a ROM, a RAM (e.g., DRAM, SDRAM, etc.), EEPROM, flash memory, a hard disk, an SD card, or other suitable magnetic, optical, physical, or electronic memory devices. The processing unit <NUM> is connected to the memory <NUM> and executes software instruction 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 lawnmower <NUM> can be stored in the memory <NUM> of the controller <NUM>. The software includes, for example, firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. The controller <NUM> is configured to retrieve from the memory <NUM> and execute, among other things, instructions related to the control processes and methods described herein. In other embodiments, the controller <NUM> includes additional, fewer, or different components.

The controller <NUM> drives the motor <NUM> to rotate the blades <NUM> and/or the plurality of wheels <NUM> in response to a user's actuation of the paddles <NUM>. Depression of the paddles <NUM> actuates the contactless switch <NUM>. The magnet <NUM> coupled to the contactless switch <NUM> rotates with actuation of the contactless switch <NUM>. Rotation of the magnet <NUM> is sensed by the rotation sensor <NUM>, which outputs a signal to the controller <NUM> to drive the motor <NUM>, and therefore the blades <NUM> and/or the plurality of wheels <NUM>. In some embodiments, the controller <NUM> controls a power switching network <NUM> (e.g., a FET switching bridge) to drive the motor <NUM>. For example, the power switching network <NUM> may include a plurality of high side switching elements (e.g., FETs) and a plurality of low side switching elements. The controller <NUM> may control each FET of the plurality of high side switching elements and the plurality of low side switching elements to drive each phase of the motor <NUM>. When the paddles <NUM> are released, the controller <NUM> may apply a braking force to the motor <NUM>. For example, the power switching network <NUM> may be controlled to more quickly deaccelerate the motor <NUM>. In some embodiments, the controller <NUM> drives an auxiliary motor to drive the plurality of wheels <NUM>. For example, the motor <NUM> is controlled to drive the blades <NUM>, and the auxiliary motor is controlled to drive the plurality of wheels <NUM>. The auxiliary motor may be controlled via a second power switching network.

The indicators <NUM> are also connected to the controller <NUM> and receive control signals from the controller <NUM> to turn on and off or otherwise convey information based on different states of the lawnmower <NUM>. The indicators <NUM> include, for example, one or more light-emitting diodes (LEDs), or a display screen. The indicators <NUM> can be configured to display conditions of, or information associated with, the lawnmower <NUM>.

The battery pack interface <NUM> is connected to the controller <NUM> and is configured to couple with the battery pack <NUM>. The battery pack interface <NUM> includes a combination of mechanical (e.g., a battery pack receiving portion) and electrical components configured to and operable for interfacing (e.g., mechanically, electrically, and communicatively connecting) the lawnmower <NUM> with the battery pack <NUM>. The battery pack interface <NUM> is coupled to the power input unit <NUM>. The battery pack interface <NUM> transmits the power received from the battery pack <NUM> to the power input unit <NUM>. The power input unit <NUM> includes active and/or passive components (e.g., voltage step-down controllers, voltage converters, rectifiers, filters, etc.) to regulate or control the power received through the battery pack interface <NUM> and to the controller <NUM>. In some embodiments, the battery pack interface <NUM> is also coupled to the power switching network <NUM>. The operation of the power switching network <NUM>, as controlled by the controller <NUM>, determines how power is supplied to the motor <NUM>.

<FIG> illustrates a control system for the battery pack <NUM>. The control system includes a controller <NUM>. The controller <NUM> is electrically and/or communicatively connected to a variety of modules or components of the battery pack <NUM>. For example, the illustrated controller <NUM> is connected to one or more battery cells <NUM> and an interface <NUM> (e.g., the interface portion <NUM> of the battery pack <NUM> illustrated in <FIG>). The controller <NUM> is also connected to one or more voltage sensors or voltage sensing circuits <NUM>, one or more current sensors or current sensing circuit <NUM>, and one or more temperature sensors or temperature sensing circuits <NUM>. The controller <NUM> includes combinations of hardware and software that are operable to, among other things, control the operation of the battery pack <NUM>, monitor a condition of the battery pack <NUM>, enable or disable charging of the battery pack <NUM>, enable or disable discharging of the battery pack <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 battery pack <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 or circuits connected to the controller <NUM>, are connected by one or more control and/or data buses (e.g., common bus <NUM>). The control and/or data buses are shown generally in <FIG> for illustrative purposes. The use of one or more control and/or data buses for the interconnection between and communication among the various modules, circuits, and components would be known to a person skilled in the art in view of the invention described herein.

The memory <NUM> is a non-transitory computer readable medium and includes, for example, a program storage area and a data storage area. The program storage area and the data storage area can include combinations of different types of memory, such as a ROM, a RAM (e.g., DRAM, SDRAM, etc.), EEPROM, flash memory, a hard disk, an SD card, or other suitable magnetic, optical, physical, or electronic memory devices. The processing unit <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 battery pack <NUM> can be stored in the memory <NUM> of the controller <NUM>. The software includes, for example, firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. The controller <NUM> is configured to retrieve from the memory <NUM> and execute, among other things, instructions related to the control processes and methods described herein. In other constructions, the controller <NUM> includes additional, fewer, or different components.

The interface <NUM> includes a combination of mechanical components (e.g., rails, grooves, latches, etc.) and electrical components (e.g., one or more terminals) configured to and operable for interfacing (e.g., mechanically, electrically, and communicatively connecting) the battery pack <NUM> with another device (e.g., a power tool, a battery pack charger, the lawnmower <NUM>, etc.). For example, the interface <NUM> is configured to receive power via a power line between the one or more battery cells <NUM> and the interface <NUM>. The interface <NUM> is also configured to communicatively connect to the controller <NUM>.

<FIG> provides a method <NUM> for controlling the output of the lawnmower <NUM>, according to some embodiments. At block <NUM>, an input switch of the lawnmower <NUM> is actuated. For example, the paddles <NUM> are actuated, thereby rotating the contactless switch <NUM>. At block <NUM>, the magnet <NUM> rotates. For example, rotation of the contactless switch <NUM> results in rotation of the magnet <NUM>.

At block <NUM>, the rotation sensor <NUM> sensor detects variation in a magnetic field generated by the rotating magnet <NUM>. In one embodiment, the rotation sensor <NUM> is a rotational Hall-effect magnetic sensor. The rotation sensor <NUM> may be configured to detect a change in a magnetic flux density component, which results from the rotation of the magnet. At block <NUM>, the rotation sensor <NUM> converts the sensed magnetic field to an output signal, which may be provided to a controller, such as controller <NUM>, as described above. In some embodiments, the rotation sensor <NUM> is an analog sensor. In some embodiments, the output of the rotation sensor <NUM> is a voltage that varies linearly with the rotation of the magnet <NUM>. However, in other examples, the output may be a non-linear output, such as a stepped output, a logarithmic output, etc..

At block <NUM>, the controller <NUM>, upon receiving the output of the rotation sensor <NUM>, controls the motor <NUM> based on the received sensor output. For example, the controller <NUM> receives the output from the rotation sensor <NUM> and drives the motor <NUM> by controlling the power switching network <NUM> based on the output from the rotation sensor <NUM>, as described above. In some embodiments, the controller <NUM> controls the output of the auxiliary motor based on the received sensor output.

In some embodiments, in block <NUM>, the rotation sensor <NUM> is a digital magnetic sensor senses the variation in the magnetic field in addition to or instead of the analog sensor. In these embodiments, the digital magnetic sensors convert the sensed magnetic field to a digital output.

Claim 1:
A lawnmower (<NUM>) comprising:
a lawnmower housing (<NUM>);
one or more cutting blades (<NUM>);
a motor (<NUM>) configured to rotate the one or more cutting blades;
a handle (<NUM>) including a switch assembly (<NUM>), characterized in that
the switch assembly includes a contactless switch (<NUM>) pivotable about an axis point (<NUM>) and a magnet (<NUM>) located at the axis point;
one or more paddles (<NUM>) extending from the handle, wherein rotation of the one or more paddles causes the contactless switch to pivot about the axis point;
a sensor (<NUM>, <NUM>) configured to sense a variation of a magnetic field of the magnet; and
a controller (<NUM>) coupled to the motor (<NUM>) and the sensor, the controller configured to:
receive, from the sensor, a value associated with the variation of the magnetic field of the magnet; and
control the motor based on the value of the variation of the magnetic field.