Patent Description:
The present disclosure is directed generally to circular saws that include lock assemblies.

Circular saws utilize a rotating circular saw blade to cut a workpiece. Circular saws may include a variety of safety, operational, and/or convenience features; however, there is demand for circular saws with improved safety, operational, and/or convenience features. Some circular saws may include conventional lock assemblies, which may, or may be utilized to, provide additional safety to a user of the circular saws, such as via selectively restricting and/or limiting rotation of the circular saw blade when such rotation might be dangerous and/or unadvised. While effective in certain circumstances, there exists an ongoing need for circular saws with improved lock assemblie:
A circular saw according to the preamble of claim <NUM> and a circular saw according to the preamble of claim <NUM> are known from <CIT>.

According to the invention circular saws defined by the features of claims <NUM> and <NUM> are provided.

Further preferred embodiments are defined by the dependent claims.

<FIG> provide examples of circular saws <NUM> and/or components thereof, according to the present disclosure. Elements that serve a similar, or at least substantially similar, purpose are labeled with like numbers in each of <FIG>, and these elements may not be discussed in detail herein with reference to each of <FIG>. Similarly, all elements may not be labeled in each of <FIG>, but reference numerals associated therewith may be utilized herein for consistency. Elements, components, and/or features that are discussed herein with reference to one or more of <FIG> may be included in and/or utilized with any of <FIG> without departing from the scope of the present disclosure.

In general, elements that are likely to be included in a particular embodiment are illustrated in solid lines, while elements that are optional are illustrated in dashed lines. However, elements that are shown in solid lines may not be essential to all embodiments and, in some embodiments, may be omitted without departing from the scope of the present disclosure.

<FIG> is a schematic illustration of examples of circular saws <NUM> according to the present disclosure, while <FIG> are less schematic illustrations of an example of a circular saw <NUM> according to the present disclosure. More specifically, <FIG> illustrates a top profile view of circular saw <NUM>, and <FIG> illustrates a right side view of circular saw <NUM>. <FIG> illustrates a left side view of circular saw <NUM> illustrating the circular saw in a fully plunged orientation <NUM>, <FIG> illustrates the left side view of circular saw <NUM> illustrating the circular saw in a fully retracted orientation <NUM>, and <FIG> illustrates the left side view of <FIG> with several covers removed. <FIG> is a front view of circular saw <NUM>, <FIG> is a rear view of circular saw <NUM>, <FIG> is a top view of circular saw <NUM>, and <FIG> is a bottom view of circular saw <NUM>.

As illustrated collectively by <FIG>, circular saws <NUM> include a motor <NUM> that includes a motor shaft <NUM> configured to rotate about a shaft axis of rotation <NUM>. Circular saws <NUM> also include an arbor <NUM> configured to receive a torque from motor <NUM> when motor shaft <NUM> rotates about the shaft rotational axis. As illustrated in dashed lines in <FIG> and in solid lines in <FIG> and <FIG>, circular saws <NUM> also may include a circular saw blade <NUM>. Circular saw blade <NUM>, when present, may be operatively attached to the circular saw via arbor <NUM> and/or may be configured for rotational movement with the arbor. Rotation of circular saw blade <NUM> may facilitate cutting of a workpiece <NUM> with the circular saw blade, as schematically illustrated in <FIG>.

Circular saws <NUM> may include any suitable type or style of circular saw that is adapted, configured, designed, and/or constructed to utilize a circular saw blade <NUM> to cut the workpiece. Examples of circular saws <NUM> include a handheld circular saw <NUM>, a miter saw <NUM>, a radial arm saw <NUM>, a table saw <NUM>, a chop saw <NUM>, an upcut saw <NUM>, a panel saw <NUM>, a plunge saw <NUM>, a track saw <NUM>, and/or a bevel saw <NUM>, as schematically illustrated in <FIG>. In some examples, circular saws <NUM> may include structures and/or features from two or more of the above saws, and/or may incorporate functionality of two or more of the above saws. As an example, and as discussed in more detail herein, a given circular saw <NUM> may be and/or may incorporate functionality of handheld circular saw <NUM>, plunge saw <NUM>, track saw <NUM>, and/or bevel saw <NUM>. Circular saws <NUM> according to the present disclosure thus may include one or more of the features disclosed herein, but circular saws <NUM> are not required to include all of the features disclosed herein.

Motor <NUM> may include any suitable structure that may provide the motive force for rotation of motor shaft <NUM> and/or for actuation of circular saw blade <NUM>. Examples of motor <NUM> include an electric motor, an AC electric motor, a DC electric motor, a brushless DC motor, a variable-speed motor, and/or a single-speed motor.

As illustrated in dashed lines in <FIG> and in solid lines in <FIG>, <FIG>, and <FIG>, circular saws <NUM> may include a gripping region <NUM> that is configured to be gripped and/or held by a user during operation of the circular saw. Gripping region <NUM>, when present, also may be referred to herein as and/or may be a handle, or hand grip.

As also illustrated in dashed lines in <FIG> and in solid lines in <FIG> and <FIG>, circular saws <NUM> may include at least one switch <NUM>. Switch(es) <NUM>, when present, may be configured to be selectively actuated by the user of the circular saw, such as to enable and/or permit electric current to be provided to at least one other component of the circular saw and/or to permit powered operation of the at least one other component of the circular saw. As examples, selective actuation of switch(es) <NUM> may be utilized to enable operation of a motor controller of the circular saw, to selectively apply an electric current to motor <NUM>, to enable the motor controller to selectively apply the electric current to the motor, and/or to permit, or direct, the motor to provide the motive force for rotation of the motor shaft. In some examples, the electric current may be utilized to power, or to directly power, at least one other component of the circular saw, such as motor <NUM>. In some such examples, the electric current also may be referred to herein as an electric power signal. In some examples, the electric current may be an electric data signal that is sent to at least one other component of the circular saw, such as the motor controller of the circular saw. In some such examples, the electric current also may be referred to herein as a data signal and/or as an electric data signal. Examples of switch <NUM> include an electrical switch, a normally open electrical switch, a momentary electrical switch, and/or a locking momentary electrical switch.

In some examples, circular saws <NUM> also include a switch lever <NUM>. Switch lever <NUM> is configured to be selectively actuated by the user of the circular saw, via application of an actuation force <NUM>, to actuate switch <NUM> and/or to direct the switch to apply the electric current to the motor. Stated another way, the user may interact with, or apply the actuation force to, switch lever <NUM>, and switch lever <NUM> may interact with, or actuate, switch <NUM>.

As also illustrated in dashed lines in <FIG> and in solid lines in <FIG>, circular saws <NUM> may include a workpiece support <NUM>. Workpiece support <NUM>, when present, may be configured to support workpiece <NUM> and/or to position the circular saw relative to the workpiece when the workpiece is cut or otherwise acted upon by the implement. For example, many circular saws <NUM> in the form of saws include workpiece support <NUM> in the form of a base plate, table, shoe, rack, or pad.

Circular saws <NUM> may include any suitable power source, and corresponding power structures, for powering motor <NUM>, for electrically powering the circular saw, and/or for providing electric current to the circular saw. Examples of the power structures include a power supply structure <NUM>, such as a power cord <NUM> and/or a battery <NUM>, as illustrated in <FIG>.

As also illustrated in dashed lines in <FIG> and in solid lines in <FIG>, circular saws <NUM> may include a blade guard <NUM>. Blade guard <NUM>, when present, may be configured to cover, to house, and/or to contain at least a region of circular saw blade <NUM>, such as to prevent, or to decrease a potential for, contact between the user and the circular saw blade. In some examples of circular saws <NUM>, blade guard <NUM> may include a retractable region <NUM>, as illustrated in <FIG>. The retractable region may be configured to fold, rotate, and/or otherwise retract when the circular saw is utilized to cut the workpiece. Retractable region <NUM> additionally or alternatively may be referred to as a retracting region <NUM> and/or a collapsing region <NUM>.

In some examples, and as discussed, circular saws <NUM> may include and/or be plunge saw <NUM>. In examples of circular saws <NUM> that are or include a plunge saw <NUM>, arbor <NUM> may be configured to move relative to workpiece support <NUM>, such as to selectively vary a region of circular saw blade <NUM> that projects from the workpiece support and/or to selectively vary a depth-of-cut of the circular saw. For example, arbor <NUM> may be configured to pivot relative to workpiece support <NUM>, as illustrated by the transition from a fully plunged orientation <NUM>, as illustrated in <FIG> and <FIG>, and a fully retracted orientation <NUM>, as illustrated in <FIG>.

As a specific example, workpiece support <NUM> may include and/or be a base plate <NUM> that defines an arbor-facing side <NUM> and an arbor-opposed side <NUM>. Arbor <NUM> may be operatively attached to arbor-facing side <NUM> of workpiece support <NUM> with, via, and/or utilizing a workpiece support pivot <NUM>. In such examples, arbor <NUM> and workpiece support <NUM> may be configured to rotate, relative to one another, about workpiece support pivot <NUM>, such as to selectively vary a region <NUM> of circular saw blade <NUM> that extends on arbor-opposed side <NUM> of the workpiece support, as perhaps best illustrated by the transition from the configuration that is illustrated in <FIG>, which illustrates fully plunged orientation <NUM>, to the configuration that is illustrated in <FIG>, which illustrates fully retracted orientation <NUM>.

Stated another way, arbor <NUM> may be configured to pivot relative to workpiece support <NUM> throughout a range of relative orientations, or relative angles, that may be bounded by the fully plunged orientation and the fully retracted orientation. For each relative orientation in this range of relative orientations, circular saw blade <NUM> may extend on arbor-opposed side <NUM> by a corresponding amount, thereby providing a corresponding maximum depth-of-cut for the circular saw.

In some examples, and as discussed, circular saws <NUM> may include and/or be track saw <NUM>. In examples of circular saws <NUM> that are or include a track saw <NUM>, workpiece support <NUM> and/or base plate <NUM> may include a rib-receiving channel <NUM>, which may be configured to receive a raised elongate rib <NUM> of a track <NUM>, as perhaps best illustrated in <FIG>. Track <NUM> also may be referred to herein as an elongate track <NUM> and may be formed from one or more elongate track segments, or track sections, <NUM>, which may be operatively attached to one another to define any suitable track length. During operation of track saws <NUM>, track <NUM> may be operatively attached, or clamped, to workpiece <NUM> such that an edge of the track corresponds to a desired cut line for the track saw. Subsequently, the track saw may be positioned, relative to the track, such that raised elongate rib <NUM> is positioned within rib-receiving channel <NUM>; and the track saw then may be translated along at least a fraction of the length of the elongate track, thereby producing a straight cut along the desired cut line.

<FIG> is a schematic illustration of examples of circular saws <NUM> that emphasize a lock assembly <NUM>, according to the present disclosure. <FIG> are less schematic illustrations of examples of components of a circular saw <NUM> that emphasize an example of a lock assembly <NUM>, according to the present disclosure. Circular saws <NUM> of <FIG> may include and/or be more detailed and/or different illustrations, views, and/or examples of circular saws <NUM> of <FIG>. As such, any of the structures, functions, and/or features disclosed herein with reference to circular saws <NUM> of <FIG> may be included in and/or utilized with circular saws <NUM> of <FIG> without departing from the scope of the present disclosure. Similarly, any of the structures, functions, and/or features disclosed herein with reference to circular saws <NUM> of <FIG> may be included in and/or utilized with circular saws <NUM> of <FIG> without departing from the scope of the present disclosure.

As illustrated collectively by <FIG>, lock assemblies <NUM> may include a switch lock <NUM>, which also may be referred to herein as a primary switch lock <NUM>, and/or a plunge lock mechanism <NUM>. Lock assemblies <NUM> also may include an arbor lock mechanism <NUM> and/or a plunge positioning mechanism <NUM>. Plunge positioning mechanism <NUM> may include a plunge enabling structure <NUM> and a secondary switch lock <NUM>. As perhaps best illustrated in <FIG> and <FIG>, primary switch lock <NUM> may include a switch <NUM>, a switch lever <NUM>, and/or an off lock lever <NUM>. Switch lever <NUM> may form a portion of and/or may be utilized to actuate switch <NUM>.

Primary switch lock <NUM> may define a switch-unlocked configuration <NUM>, within which the switch lock permits actuation of the switch lever by the user of the circular saw, and a switch-locked configuration <NUM>, within which the switch lock resists actuation of the switch lever by the user of the circular saw. As an example, off lock lever <NUM> may be configured to be selectively actuated, by the user and via rotation about an off lock lever axis of rotation <NUM>, to selectively transition switch lock <NUM> between a switch-locked configuration <NUM>, as illustrated in <FIG>, and a switch-unlocked configuration <NUM>, as illustrated in <FIG>. When in switch-locked configuration <NUM> of <FIG>, off lock lever <NUM> and switch lever <NUM> may interact to avoid actuation and/or restrict motion of switch <NUM>. In contrast, and when in a switch-unlocked configuration <NUM> of <FIG>, switch lever <NUM> may be moved or may be free to be actuated by a user of circular saw <NUM>, such as to provide electric current <NUM> to motor <NUM>, as illustrated in <FIG>, and/or to initiate and/or maintain rotation of circular saw blade <NUM>.

Switch lever <NUM> and/or switch <NUM> may be biased to move the switch to a corresponding off position, in which the switch does not provide the electric current, such as via a switch biasing mechanism <NUM>, which in some examples may be internal to switch <NUM>. Similarly, switch lock <NUM> and/or off lock lever <NUM> thereof may be biased to move to switch-locked configuration <NUM>, such as via a switch lock biasing mechanism <NUM>, which also may be referred to herein as an off lock lever biasing mechanism <NUM>. Examples of switch lock biasing mechanism <NUM> include a switch lock biasing mechanism resilient member, a switch lock biasing mechanism spring, a switch lock biasing mechanism coil spring, and/or a switch lock biasing mechanism torsion spring.

As perhaps best illustrated in <FIG> and <FIG>, off lock lever <NUM> may include an off lock lever stop <NUM>, such as an interacting surface, that may restrict motion and/or actuation of switch lever <NUM>. In addition, switch lever <NUM> may include a switch lever stop <NUM>. Switch lever stop <NUM> may be configured to contact, to operatively contact, and/or to press against off lock lever stop <NUM> to resist motion of switch lever <NUM> when off lock lever <NUM> is in switch-locked configuration <NUM> of <FIG>. This may produce and/or generate a contact region <NUM> between the off lock lever stop and the switch lever stop, as illustrated in <FIG>. Stated another way, when switch lock <NUM> is in switch-locked configuration <NUM> of <FIG>, off lock lever stop <NUM> may operatively engage and/or press against switch lever stop <NUM> to resist motion of switch lever <NUM> to actuate switch <NUM>. In contrast, and when switch lock <NUM> is in switch-unlocked configuration <NUM> of <FIG>, switch lever stop <NUM> may be free from operative engagement with off lock lever stop <NUM> during actuation of switch lever <NUM> to actuate switch <NUM>.

Switch lever <NUM> also may include a user engagement surface <NUM>. The user engagement surface may be configured to receive actuation force <NUM> from the user, as illustrated in <FIG>. Upon receipt of the actuation force, switch lever <NUM> may be configured to operatively translate along a switch lever translation axis <NUM>. The switch lever translation axis may intersect, or extend through, off lock lever axis of rotation <NUM>, as illustrated in <FIG>.

In some examples of lock assemblies <NUM>, user engagement surface <NUM> and switch lever stop <NUM> may be at least partially, or even completely, on opposed sides of switch lever translation axis <NUM>. In some examples, user engagement surface <NUM> and contact region <NUM> of <FIG> may be at least partially, or even completely, on opposed sides of switch lever translation axis <NUM>. In some examples, switch lock <NUM> and/or off lock lever <NUM> and switch lever <NUM> thereof may be configured such that actuating (e.g., pulling and/or squeezing to apply the actuation force) switch lever <NUM> while the switch lock is in switch-locked configuration <NUM> of <FIG> generates an engagement force between the switch lock and the switch lever, such as between off lock lever stop <NUM> and switch lever stop <NUM>. In some such examples, a magnitude of this engagement force may increase with an increase in the actuation force.

Stated another way, the off lock lever and the switch lever may be configured such that if the user intentionally or unintentionally exerts a force to switch lever <NUM>, such as to intentionally or accidentally actuate switch lever <NUM>, without first actuating off lock lever <NUM>, off lock lever stop <NUM> may resist motion of the switch lever. This resistance may increase with increasing force applied to the switch lever, thereby decreasing a potential for inadvertent actuation of switch <NUM> via actuation of switch lever <NUM> without first actuating off lock lever <NUM>.

In some examples, and when switch lock <NUM> is in switch-locked configuration <NUM> of <FIG>, application of the actuation force to switch lever <NUM> may cause the switch lever to apply a tensile force, and in some examples only a tensile force, to switch lock <NUM> and/or to off lock lever <NUM> thereof. In some examples, application of the actuation force to the switch lever also may cause the switch lever to apply a torsional force to the switch lock and/or to off lock lever <NUM> thereof. In some such examples, a magnitude of the tensile force may be greater than a magnitude of the torsional force. In some such examples, application of the actuation force may urge switch lock <NUM> and/or off lock lever <NUM> thereof toward switch-locked configuration <NUM> of <FIG>, such as via the torsional force. In some such examples, application of the actuation force may urge switch lock <NUM> and/or off lock lever <NUM> thereof away from switch-unlocked configuration <NUM> of <FIG>, such as via the torsional force.

In some examples, and when switch lock <NUM> is in switch-unlocked configuration <NUM> of <FIG>, and during application of the actuation force to switch lever <NUM>, the switch lever may be free from contact with switch lock <NUM> and/or with off lock lever <NUM> thereof. Additionally or alternatively, the switch lever may be only in sliding contact with switch lock <NUM> and/or with the off lock lever. Additionally or alternatively, the switch lever may be free from the engagement force exerted by the switch lock and/or by the off lock lever.

In examples of circular saws <NUM> that are, or include the structures and/or features of, plunge saw <NUM>, lock assembly <NUM> further may include a plunge lock <NUM>, which is illustrated in <FIG> and <FIG>. Plunge lock <NUM>, when present, may define a plunge locked configuration <NUM>, as illustrated in <FIG> and <FIG>, and a plunge unlocked configuration <NUM>, as illustrated in <FIG> and <FIG>. When in plunge locked configuration <NUM>, plunge lock <NUM> may restrict plunging of the plunge saw. As an example, plunge lock <NUM> may block the movement of motor <NUM> and/or circular saw blade <NUM> relative to workpiece support <NUM> and/or in a direction that is perpendicular to the workpiece support. Stated another way, and when in plunge locked configuration <NUM>, motion and/or rotation of circular saw blade <NUM> and/or of motor <NUM> relative to workpiece support <NUM> and/or about workpiece support pivot <NUM> may be resisted and/or restricted by the plunge lock. Also when in plunge locked configuration <NUM>, at least a region of the circular saw blade is covered by blade guard <NUM>, as illustrated in <FIG>, such as to prevent the circular saw blade from being touched by the user of the circular saw. In contrast, and when in plunge unlocked configuration <NUM>, motor <NUM> and/or circular saw blade <NUM> may be free to move and/or rotate, relative to workpiece support <NUM>, such that the circular saw blade protrudes through a plane defined by arbor-opposed side <NUM> of the workpiece support and/or projects from the arbor-opposed side of the workpiece support, as illustrated in <FIG>.

Plunge lock <NUM> may include any suitable structure that may be configured to selectively permit and/or restrict plunging of the plunge saw, such as via transitioning between plunge locked configuration <NUM> and plunge unlocked configuration <NUM>. As an example, and as illustrated in <FIG>, plunge lock <NUM> may include a plunge lock arm <NUM>. When in plunge locked configuration <NUM> of <FIG>, plunge lock arm <NUM> may interact with and/or contact a locking surface <NUM> of a plunge guide assembly <NUM> of plunge lock <NUM>. In contrast, when in plunge unlocked configuration <NUM>, plunge lock arm <NUM> may move and/or rotate such that the plunge lock arm does not interact and/or contact locking surface <NUM>, as illustrated in <FIG>. In some examples, plunge lock <NUM> further may include a plunge lock lever <NUM> that is configured to actuate plunge lock arm <NUM>. Plunge lock lever <NUM> may form a portion of off lock lever <NUM>, thereby permitting both actuation of switch <NUM> and plunging of the circular saw upon actuation of off lock lever <NUM>.

Plunge lock arm <NUM> may be biased toward and/or to plunge locked configuration <NUM>, such as via a plunge lock biasing mechanism <NUM>. Examples of plunge lock biasing mechanism <NUM> include a plunge lock biasing mechanism spring, a plunge lock biasing mechanism torsion spring, and/or a plunge lock biasing mechanism coil spring.

Plunge lock biasing mechanism <NUM> and switch lock biasing mechanism <NUM> together may provide redundant mechanisms via which circular saws <NUM>, according to the present disclosure, decrease a potential for contact, or for inadvertent contact, between circular saw blade <NUM> and a user of the circular saw. Stated another way, it may be necessary to overcome the bias provided by both plunge lock biasing mechanism <NUM> and switch lock biasing mechanism <NUM> before a rotating circular saw blade <NUM> may be exposed in a manner that permits contact between the rotating circular saw blade and the user.

As perhaps best illustrated in <FIG>, <FIG>, and <FIG>, lock assembly <NUM> may include an assembly lever <NUM>. Assembly lever <NUM> also may be referred to herein as a blade change lever <NUM>. Assembly lever <NUM> may be configured to be selectively transitioned between a blade-change mode orientation <NUM> and a material-cutting mode orientation <NUM>. Such a transition may selectively and/or concurrently transition or otherwise configure primary switch lock <NUM>, an arbor lock <NUM>, plunge lock <NUM>, plunge positioning mechanism <NUM>, and/or the secondary switch lock <NUM> between corresponding locked and unlocked states. Stated another way, assembly lever <NUM> may be configured to be transitioned between a configuration that permits and/or facilitates removal and/or changing of circular saw blade <NUM>, i.e., blade-change mode orientation <NUM>, and a configuration that permits and/or facilitates operation of the circular saw to cut a workpiece, i.e., material-cutting mode orientation <NUM>.

As an example, when assembly lever <NUM> is in blade-change mode orientation <NUM>, and as illustrated in <FIG>, switch lock <NUM> is in a corresponding switch-locked configuration <NUM>, and arbor lock <NUM> is in a corresponding arbor-locked configuration <NUM>. In contrast, when assembly lever <NUM> is in material-cutting mode orientation <NUM>, and as illustrated in <FIG>, switch lock <NUM> is in a corresponding switch-unlocked configuration <NUM>, and arbor lock <NUM> is in a corresponding arbor-unlocked configuration <NUM>.

As discussed, when switch lock <NUM> is in switch-unlocked configuration <NUM>, switch <NUM> may be actuated by the user, such as to provide the electric current to the at least one other component of the circular saw. In contrast, when switch lock <NUM> is in switch-locked configuration <NUM>, lock assembly <NUM> resists actuation of switch <NUM> by the user of the circular saw and/or the switch is restricted from providing the electric current to the at least one other component of the circular saw.

Assembly lever <NUM> may be configured to be selectively transitioned from material-cutting mode orientation <NUM> to blade-change mode orientation <NUM> to permit and/or to facilitate a blade change of the circular saw blade. Additionally or alternatively, assembly lever <NUM> may be configured to be selectively transitioned from blade-change mode orientation <NUM> to material-cutting mode orientation <NUM> to permit and/or to facilitate rotation of the circular saw blade and/or operation of the circular saw to cut a workpiece.

In some examples of lock assembly <NUM>, assembly lever <NUM> may include a plurality of detent positions <NUM>. The plurality of detent positions may include at least a locked lever detent position <NUM>, as illustrated in <FIG>, and an unlocked lever detent position <NUM>, as illustrated in <FIG>. As perhaps best illustrated in <FIG>, lock assembly <NUM> and/or assembly lever <NUM> thereof may include, may define, and/or may be operatively attached to a resilient spring <NUM> configured to interlock with a corresponding plurality of spring recesses <NUM> to define the plurality of detent positions. In some such examples, spring recesses <NUM> may be spaced apart from, may be distinct from, and/or may be defined by a structure other than assembly lever <NUM>.

Assembly lever <NUM> may be moved from one detent position to another detent position. When the assembly lever leaves a given detent position, resilient spring <NUM> may be deformed, which may provide a tactile feedback to the user. Between detent positions, resilient spring <NUM> may generate a frictional force, which may cause a more controllable movement. As an example, forces generated by biasing mechanisms, such as switch lock biasing mechanism <NUM> and/or plunge lock biasing mechanism <NUM>, may be damped by the frictional force. When assembly lever <NUM> reaches and/or enters a given spring recess <NUM>, the action of the resilient spring again may provide a tactile feedback to the user. With the above in mind, the presence of resilient spring <NUM> and spring recesses <NUM> may improve a user's ability to know and/or to recognize corresponding positions of assembly lever <NUM> that define material-cutting mode orientation <NUM> and blade-change mode orientation <NUM>, respectively.

When assembly lever <NUM> is in material-cutting mode orientation <NUM>, which also may be referred to herein as a sawing mode <NUM> and/or as a saw running mode <NUM>, arbor lock <NUM> may be in arbor-unlocked configuration <NUM>, and arbor <NUM> of circular saw <NUM> may be free to rotate, such as may be responsive to receipt of the motive force from motor <NUM>. In contrast, when assembly lever <NUM> is in blade-change mode orientation <NUM>, arbor lock <NUM> may be in arbor-locked configuration <NUM> and may restrict rotation of arbor <NUM> about an arbor rotational axis <NUM>.

As a more specific example, and as illustrated in <FIG>, lock assembly <NUM> may include an arbor lock arm <NUM> that may be configured for selective engagement within a recess <NUM> of a collar <NUM> that extends from arbor <NUM>. When assembly lever <NUM> is in material-cutting mode orientation <NUM> of <FIG>, the assembly lever maintains a spaced-apart relationship between arbor lock arm <NUM> and collar <NUM>. However, when assembly lever <NUM> is transitioned to blade-change mode orientation <NUM> of <FIG>, arbor lock arm <NUM> is biased toward collar <NUM>, as illustrated in <FIG>, and will move into a corresponding recess <NUM> when collar <NUM> is rotated to a corresponding angular position that aligns the arbor lock arm with the recess, as illustrated in <FIG>. Once arbor lock arm <NUM> is positioned within recess <NUM>, arbor <NUM> is locked, or otherwise restricted, from rotation about its axis of rotation at least until the arbor lock arm is removed, such as via actuation of assembly lever <NUM>.

Coupling between assembly lever <NUM> and arbor lock arm <NUM> may permit an arbor lock biasing mechanism <NUM> to affect the orientation of the assembly lever as well. A third, or an intermediate, orientation may be defined between blade-change mode orientation <NUM> and material-cutting mode orientation <NUM> of assembly lever <NUM>. In this third orientation, arbor lock biasing mechanism <NUM>, which pushes arbor lock arm <NUM> in the direction of collar <NUM>, may store more energy than when in the two end positions of assembly lever <NUM>. This may create a bi-stable, or a multi-stable, mechanism via which arbor lock biasing mechanism <NUM> pushes the assembly lever <NUM> from points that are between material-cutting mode orientation <NUM> and blade-change mode orientation <NUM> toward and/or to a corresponding one of the orientations.

In some examples, the intermediate orientation also may be a stable, or semi-stable, position. In some such examples, arbor lock biasing mechanism <NUM> may not urge assembly lever <NUM> from the intermediate orientation. However, arbor lock biasing mechanism <NUM> may urge the assembly lever toward the material-cutting mode orientation when the assembly lever is between the intermediate orientation and the material cutting-mode orientation and/or may urge the assembly lever toward the blade-change mode orientation when the assembly lever is between the blade-change mode orientation and the intermediate orientation. Such a configuration may decrease a potential for an unexpected, or undesired, change in orientation of assembly lever <NUM> during operation of the circular saw and/or while changing the circular saw blade. Examples of arbor lock biasing mechanism <NUM> include an arbor lock biasing mechanism resilient member, an arbor lock biasing mechanism spring, an arbor lock biasing mechanism coil spring, and an arbor lock biasing mechanism torsion spring.

In order to facilitate a blade change of circular saw blade <NUM>, it may be beneficial to lock circular saws <NUM> that include plunge saws <NUM> at a certain, a predetermined, and/or a fixed plunge orientation, which may be an intermediate plunge orientation between fully retracted orientation <NUM> and fully plunged orientation <NUM>. An example of such an intermediate plunge orientation is illustrated in <FIG> and <FIG>, and indicated at <NUM>. Such an intermediate plunge position may facilitate access to the fastener that operatively attaches the circular saw blade to the circular saw.

With this in mind, lock assembly <NUM> and/or plunge positioning mechanism <NUM> may be configured to define, or to at least temporarily lock the circular saw in, intermediate plunge orientation <NUM>. This may be accomplished in any suitable manner. As an example, and as perhaps best illustrated in <FIG>, lock assembly <NUM> may include a plunge positioning arm <NUM>, and plunge guide assembly <NUM> may define a plunge positioning arm recess <NUM>.

This mechanism may include the assembly lever <NUM>, a spring-loaded plunge positioning arm <NUM> and a plunge guide assembly <NUM> that defines a plunge positioning arm recess <NUM>. In such a configuration, and when assembly lever <NUM> is in material cutting mode <NUM>, the assembly lever urges plunge positioning arm <NUM> away from plunge positioning arm recess <NUM>. As such, the plunge positioning arm will not interlock with the plunge positioning arm recess and/or the circular saw may move between the fully plunged orientation and the fully retracted orientation.

However, when assembly lever <NUM> is in blade-change mode orientation <NUM>, the assembly lever permits plunge positioning arm <NUM> to move, or to be biased toward, plunge positioning arm recess <NUM>. As such, and when the plunge positioning arm is aligned with the plunge positioning arm recess, the plunge positioning arm interlocks with the plunge positioning arm recess, thereby locking the circular saw in intermediate plunge orientation <NUM>, as perhaps best illustrated in <FIG> and <FIG>. In some examples, a plunge positioning arm biasing mechanism <NUM> may urge, or bias, the plunge positioning arm toward and/or into the plunge positioning arm recess. Stated another way, when the plunging movement reaches the blade change position illustrated in <FIG> and <FIG>, plunge positioning arm biasing mechanism <NUM> may urge plunge positioning arm <NUM> into plunge positioning arm recess <NUM>, thereby stopping plunging motion in the intermediate plunge orientation, which also may be referred to herein as the blade change position.

As discussed, plunge lock arm <NUM> may selectively disable plunging of motor <NUM> and/or circular saw blade <NUM> relative to workpiece support <NUM>. With this in mind, it may be beneficial to selectively transition plunge lock arm <NUM> to a configuration in which the motor and/or the circular saw blade may plunge relative to the workpiece support, such as to permit and/or facilitate the blade change discussed above. With this in mind, and in examples of circular saws <NUM> that are or include plunge saw <NUM>, lock assembly <NUM> further may include a plunge lock deactivation mechanism, which the user may utilize to permit plunging and actuation of plunge positioning mechanism <NUM> in one single movement of assembly lever <NUM>.

This may be accomplished in any suitable manner. As an example, assembly lever <NUM> may include a plunge enabling surface <NUM>, as illustrated in <FIG> and <FIG>. Plunge enabling surface <NUM> may selectively enable and/or disable actuation of plunge lock arm <NUM> and/or plunge lock lever <NUM>. As an example, when assembly lever <NUM> is in material-cutting mode orientation <NUM>, the plunge lock lever may urge plunge lock arm <NUM> and plunge positioning arm <NUM> to corresponding orientations that permit plunging of the circular saw. In contrast, when assembly lever <NUM> is in blade-change mode orientation <NUM>, the assembly lever may urge plunge lock arm <NUM> toward a corresponding orientation that permits plunging of the circular saw and also may urge plunge lock lever <NUM> toward and/or into plunge positioning arm recess <NUM>, such as to define intermediate plunge orientation <NUM>.

Plunge lock <NUM> may be connected to the primary switch lock <NUM> such that deactivation of plunge lock <NUM> causes deactivation of switch lock <NUM>. To keep switch lever <NUM> locked in the off position when assembly lever <NUM> is in blade-change mode orientation <NUM> that is illustrated in <FIG>, lock assembly <NUM> may include secondary switch lock <NUM>. As illustrated in <FIG>, secondary switch lock <NUM> may be defined by a blocking surface <NUM> of assembly lever <NUM> that may interact with, or selectively resist actuation of, switch lever <NUM>.

As an example, when assembly lever <NUM> is in material-cutting mode orientation <NUM>, and as illustrated in <FIG>, blocking surface <NUM> may not resist actuation of switch lever <NUM>, blocking surface <NUM> stays apart from switch lever <NUM>, and/or the movement of switch lever <NUM> is not restricted by secondary switch lock <NUM>. If the primary switch lock <NUM> is disabled, the switch lever <NUM> can be pulled to start the saw with switch <NUM>. In contrast, when assembly lever <NUM> is in blade-change mode orientation <NUM>, and as illustrated in <FIG>, blocking surface <NUM> restricts motion, or actuation, of the switch lever. As such, the circular saw cannot be started.

As used herein, the term "and/or" placed between a first entity and a second entity means one of (<NUM>) the first entity, (<NUM>) the second entity, and (<NUM>) the first entity and the second entity. Multiple entities listed with "and/or" should be construed in the same manner, i.e., "one or more" of the entities so conjoined. Other entities may optionally be present other than the entities specifically identified by the "and/or" clause, whether related or unrelated to those entities specifically identified. Thus, as a non-limiting example, a reference to "A and/or B," when used in conjunction with open-ended language such as "comprising" may refer, in one embodiment, to A only (optionally including entities other than B); in another embodiment, to B only (optionally including entities other than A); in yet another embodiment, to both A and B (optionally including other entities). These entities may refer to elements, actions, structures, steps, operations, values, and the like.

As used herein, the phrase "at least one," in reference to a list of one or more entities should be understood to mean at least one entity selected from any one or more of the entities in the list of entities, but not necessarily including at least one of each and every entity specifically listed within the list of entities and not excluding any combinations of entities in the list of entities. This definition also allows that entities may optionally be present other than the entities specifically identified within the list of entities to which the phrase "at least one" refers, whether related or unrelated to those entities specifically identified. Thus, as a non-limiting example, "at least one of A and B" (or, equivalently, "at least one of A or B," or, equivalently "at least one of A and/or B") may refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including entities other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including entities other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other entities). In other words, the phrases "at least one," "one or more," and "and/or" are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions "at least one of A, B, and C," "at least one of A, B, or C," "one or more of A, B, and C," "one or more of A, B, or C," and "A, B, and/or C" may mean A alone, B alone, C alone, A and B together, A and C together, B and C together, A, B, and C together, and optionally any of the above in combination with at least one other entity.

As used herein the terms "adapted" and "configured" mean that the element, component, or other subject matter is designed and/or intended to perform a given function.

As used herein, the phrase, "for example," the phrase, "as an example," and/or simply the term "example," when used with reference to one or more components, features, details, structures, embodiments, and/or methods according to the present disclosure, are intended to convey that the described component, feature, detail, structure, embodiment, and/or method is an illustrative, nonexclusive example of components, features, details, structures, embodiments, and/or methods according to the present disclosure. Thus, the described component, feature, detail, structure, embodiment, and/or method is not intended to be limiting, required, or exclusive/exhaustive; and other components, features, details, structures, embodiments, and/or methods, including structurally and/or functionally similar and/or equivalent components, features, details, structures, embodiments, and/or methods, are also within the scope of the present disclosure.

As used herein, "at least substantially," when modifying a degree or relationship, may include not only the recited "substantial" degree or relationship, but also the full extent of the recited degree or relationship. A substantial amount of a recited degree or relationship may include at least <NUM>% of the recited degree or relationship. For example, an object that is at least substantially formed from a material includes objects for which at least <NUM>% of the objects are formed from the material and also includes objects that are completely formed from the material. As another example, a first length that is at least substantially as long as a second length includes first lengths that are within <NUM>% of the second length and also includes first lengths that are as long as the second length.

Claim 1:
A circular saw (<NUM>), comprising:
a motor (<NUM>) including a motor shaft (<NUM>) configured to rotate about a shaft rotational axis;
an arbor (<NUM>) configured to operatively attach a circular saw blade (<NUM>) to the circular saw (<NUM>) and to receive a torque from the motor (<NUM>) when the motor shaft (<NUM>) rotates about the shaft rotational axis;
a switch (<NUM>) configured to selectively apply an electric current to the motor (<NUM>);
a switch lever (<NUM>) configured to be selectively actuated, by a user of the circular saw (<NUM>) and via application of an actuation force, to actuate the switch (<NUM>) and thereby to apply the electric current to the motor (<NUM>); and
a lock assembly (<NUM>) that includes a switch lock (<NUM>), wherein the switch lock (<NUM>):
(i) defines a switch-locked configuration (<NUM>) in which the switch lock (<NUM>) resists actuation of the switch lever (<NUM>) by the user of the circular saw (<NUM>);
(ii) defines a switch-unlocked configuration (<NUM>) in which the switch lever (<NUM>) is free to be actuated by the user of the circular saw (<NUM>) to actuate the switch (<NUM>); and
(iii) includes an off lock lever (<NUM>) configured to be selectively actuated, by the user and via rotation about an off lock lever axis of rotation (<NUM>), to selectively transition the switch lock (<NUM>) between the switch-locked configuration (<NUM>) and the switch-unlocked configuration (<NUM>),
characterized in that
the off lock lever (<NUM>) includes an off lock lever stop (<NUM>), wherein the switch lever (<NUM>) includes a switch lever stop (<NUM>), which is configured to contact the off lock lever stop (<NUM>) to resist motion of the switch lever (<NUM>) when the off lock lever (<NUM>) is in the switch-locked configuration (<NUM>), wherein the switch lever (<NUM>) includes a user engagement surface (<NUM>), which is configured to receive the actuation force from the user, wherein, upon receipt of the actuation force, the switch lever (<NUM>) is configured to operatively translate along a switch lever translation axis (<NUM>) that intersects the off lock lever axis of rotation (<NUM>), and further wherein the user engagement surface (<NUM>) and the switch lever stop (<NUM>) are at least partially on opposed sides of the switch lever translation axis (<NUM>).