Patent Description:
The present disclosure relates to power tools, and more specifically, the present invention relates to an oscillating power tool according to the preamble of claim <NUM>. Such an oscillating power tool is known from <CIT>. Power tools utilize the rotation of a motor to provide useful oscillating rotational output for operations such as cutting, sanding, grinding, etc..

The invention provides an oscillating power tool, according to claim <NUM>, including a housing, and a motor disposed generally within the housing, the motor including a drive shaft rotatable about a motor axis. The oscillating power tool also includes an output spindle configured to be driven by the motor and journaled for oscillating rotation about an oscillation axis. The oscillating power tool also includes a drive mechanism configured to convert rotation of the drive shaft into oscillating rotation of the output spindle about the oscillation axis, the drive mechanism including an eccentric member configured to rotate off center about the motor axis, and a forked member operatively coupled to the eccentric member and configured for oscillating rotation about the oscillation axis in response to rotation of the eccentric member. Oscillating rotation of the forked member has an angular amplitude about the oscillation axis. The eccentric member is movable with respect to the forked member to change the angular amplitude of oscillating rotation of the forked member. The eccentric member includes a front surface and a rear surface opposite the front surface. The front surface is closer to the output spindle than the rear surface, and the rear surface is closer to the motor than the front surface. A set of three orthogonal reference planes intersect each other at a geometric center of the eccentric member, the set of three orthogonal reference planes including first and second planes defining four substantially equal quadrants on the front and rear surfaces of the eccentric member and a third plane separating the front surface from the rear surface. The oscillating power tool also includes an amplitude adjustment actuator configured to move the eccentric member to change the angular amplitude of oscillating rotation of the forked member. The amplitude adjustment actuator is configured to engage the eccentric member on the front surface and on the rear surface. The amplitude adjustment actuator is configured to engage the eccentric member on both sides of the first plane. The amplitude adjustment actuator is configured to engage the eccentric member on both sides of the second plane.

In another aspect, the disclosure provides an oscillating power tool including a housing, and a motor disposed generally within the housing, the motor including a drive shaft rotatable about a motor axis. The oscillating power tool also includes an output spindle configured to be driven by the motor and journaled for oscillating rotation about an oscillation axis. The oscillating power tool also includes a drive mechanism configured to convert rotation of the drive shaft into oscillating rotation of the output spindle about the oscillation axis, the drive mechanism including an eccentric member configured to rotate off center about the motor axis, and a forked member operatively coupled to the eccentric member and configured for oscillating rotation about the oscillation axis in response to rotation of the eccentric member. Oscillating rotation of the forked member has an angular amplitude about the oscillation axis. The eccentric member is movable with respect to the forked member to change the angular amplitude of oscillating rotation of the forked member. The oscillating power tool also includes an amplitude adjustment actuator configured to move the eccentric member to change the angular amplitude of oscillating rotation of the forked member, the amplitude adjustment actuator defining a receptacle. At least a portion of the forked member is disposed in the receptacle.

In another aspect, the disclosure provides an oscillating power tool including a housing, and a motor disposed generally within the housing, the motor including a drive shaft rotatable about a motor axis. The oscillating power tool also includes an output spindle configured to be driven by the motor and journaled for oscillating rotation about an oscillation axis. The oscillating power tool also includes a drive mechanism configured to convert rotation of the drive shaft into oscillating rotation of the output spindle about the oscillation axis, the drive mechanism including an eccentric member configured to rotate off center about the motor axis, and a forked member operatively coupled to the eccentric member and configured for oscillating rotation about the oscillation axis in response to rotation of the eccentric member. Oscillating rotation of the forked member has an angular amplitude about the oscillation axis. The eccentric member is movable with respect to the forked member to change the angular amplitude of oscillating rotation of the forked member. The oscillating power tool also includes an amplitude adjustment actuator configured to move the eccentric member to change the angular amplitude of oscillating rotation of the forked member. The amplitude adjustment actuator includes a first actuation surface extending through a first aperture in the housing, and the amplitude adjustment actuator includes a second actuation surface extending through a second aperture in the housing separate from the first aperture.

Before any implementations of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of implementation and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of other implementations and of being practiced or of being carried out in various ways. Also, it should be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting.

<FIG> illustrate a power tool <NUM> according to one implementation of the invention. The power tool <NUM> includes a main body <NUM> having a housing <NUM> defining a handle <NUM> and a head <NUM>. The head <NUM> is driven by a motor <NUM> (<FIG>) disposed within the housing <NUM>. The handle <NUM> includes a grip portion <NUM> providing a surface suitable for grasping by an operator to operate the power tool <NUM>. The housing <NUM> generally encloses the motor <NUM>. The term "generally" is used herein to mean at least mostly, but not necessarily exactly or completely.

The motor <NUM> in the illustrated implementation is an electric motor driven by a power source such as a battery pack <NUM> (<FIG>), but may be powered by other power sources such as an AC power cord in other implementations. In yet other implementations, the power tool <NUM> may be pneumatically powered or powered by any other suitable power source and the motor <NUM> may be a pneumatic motor or other suitable type of motor. The motor <NUM> includes a motor drive shaft <NUM> (<FIG>) extending therefrom and driven for rotation about a motor axis A. The motor <NUM> may be a variable speed or multi-speed motor. In other implementations, other suitable motors may be employed.

The battery pack <NUM> (<FIG>) is a removable and rechargeable battery pack. In the illustrated implementation, the battery pack <NUM> may include a <NUM>-volt battery pack, a <NUM>-volt battery pack, an <NUM>-volt battery pack, or any other suitable voltage, and includes Lithium-ion battery cells (not shown). Additionally or alternatively, the battery cells may have chemistries other than Lithium-ion such as, for example, Nickel Cadmium, Nickel Metal-Hydride, or the like. In other implementations, other suitable batteries and battery packs may be employed.

The main body <NUM> also includes a power actuator <NUM> (<FIG>). The power actuator <NUM> is movably coupled with the housing <NUM> and is actuatable to power the motor <NUM>, e.g., to electrically couple the battery pack <NUM> and the motor <NUM> to run the motor <NUM>. The power actuator <NUM> may be a sliding actuator as shown, or in other implementations may include a trigger-style actuator, a button, a lever, a knob, etc..

The housing <NUM> also houses a drive mechanism <NUM> (<FIG>) for converting rotary motion of the motor drive shaft <NUM> into oscillating motion of an output mechanism <NUM>. As shown in <FIG>, the output mechanism <NUM> includes a spindle <NUM> having an accessory holder <NUM> disposed at a distal end thereof, and a plunger <NUM> and a threaded clamping shaft <NUM> disposed within the spindle <NUM>, which is hollow in the illustrated implementation. As shown in <FIG>, the spindle <NUM> terminates, at a free end, with the accessory holder <NUM>. The accessory holder <NUM> is configured to receive an accessory <NUM> (<FIG>) such as a blade, and a clamping mechanism <NUM> (<FIG>) clamps the accessory <NUM> to the accessory holder <NUM>. Specifically, the accessory holder <NUM> includes a first locating feature <NUM>, such as a protrusion or protrusions protruding from a face <NUM> of the accessory holder <NUM>, sized and shaped for receiving the accessory <NUM> having a second locating feature (not shown) such as an opening configured to mate with the first locating feature <NUM>. The threaded clamping shaft <NUM> includes a clamping flange <NUM> at a distal end thereof for clamping the accessory <NUM> to the accessory holder <NUM> for oscillating motion with the spindle <NUM>. An operator may thread the threaded clamping shaft <NUM> into the plunger <NUM> to hand tighten the clamping flange <NUM> against the accessory <NUM>. A clamping actuator <NUM>, such as a lever, is configured to apply and release a clamping force from a biasing member <NUM>, such as a spring. In a first position of the clamping actuator <NUM> (<FIG>), the biasing member <NUM> applies the clamping force pulling the clamping flange <NUM> towards the accessory holder <NUM> to clamp the accessory <NUM> tightly. In a second position (not shown) of the clamping actuator <NUM>, the plunger <NUM> compresses the biasing member <NUM> to remove the clamping force from the accessory holder <NUM> such that the threaded clamping shaft <NUM> can be unthreaded and removed to release the accessory <NUM>. The spindle <NUM> defines an oscillation axis B substantially perpendicular to the motor axis A about which the spindle <NUM> oscillates, as will be described in greater detail below. In other implementations, other clamping actuators may be employed, such as a button, a knob, etc..

As shown in <FIG>, the drive mechanism <NUM> includes an eccentric shaft <NUM> coupled to the motor drive shaft <NUM> and offset (e.g., off center) from the motor axis A, an eccentric bearing <NUM> coupled to the eccentric shaft <NUM>, and a forked yoke <NUM>. In some implementations, the eccentric shaft <NUM> and the eccentric bearing <NUM> may be formed as one piece. The term "an eccentric member" as used herein may refer to the eccentric shaft <NUM> and/or the eccentric bearing <NUM>. The forked yoke <NUM> is coupled fixedly to the spindle <NUM> by way of a sleeve portion <NUM>, and the forked yoke <NUM> and spindle <NUM> are collectively mounted for oscillating rotation about the oscillation axis B. The forked yoke <NUM> does not slide or move with respect to the housing <NUM> other than to oscillate in a rotating fashion about the oscillation axis B.

The forked yoke <NUM> also includes two arms 64a, 64b (<FIG>) extending from the sleeve portion <NUM> and defining a recess <NUM> therebetween. The arms 64a, 64b are disposed adjacent generally opposite sides of the eccentric bearing <NUM>, which is disposed in the recess <NUM>. Each arm 64a, 64b engages an outer circumferential surface <NUM> of the eccentric bearing <NUM>. As the eccentric bearing <NUM> rotates off center about the motor axis A, the eccentric bearing <NUM> pushes each arm 64a, 64b in an alternating fashion to cause the forked yoke <NUM> to oscillate. Thus, the forked yoke <NUM> oscillates about the oscillation axis B to convert the eccentric rotary motion of the eccentric bearing <NUM> about the motor axis A into oscillating motion of the spindle <NUM> and the accessory holder <NUM> about the oscillation axis B.

<FIG> illustrates an angular amplitude of oscillation C of the spindle <NUM> about the oscillation axis B. Depending on the type of accessory <NUM> attached, the angular amplitude of oscillation C corresponds to a stroke length L of the accessory <NUM>. As illustrated in <FIG>, the accessory <NUM> may include a blade having a distal working end with teeth <NUM>. The stroke length L is defined by the total arc length of the path of the working end (e.g., of the teeth <NUM>) of the accessory <NUM> during oscillation about the axis B.

As illustrated schematically in <FIG>, the angular amplitude of oscillation C is adjustable. As described above, the forked yoke <NUM> is fixed with respect to the housing <NUM> other than to rotatably oscillate about the oscillation axis B. The eccentric bearing <NUM> is movable with respect to the forked yoke <NUM> (and with respect to the housing <NUM>) in a horizontal direction H generally parallel to the motor axis A, towards (<FIG>) and away from (<FIG>) the oscillation axis B as shown. In other words, the eccentric bearing <NUM> is movable within the recess <NUM>, towards and away from the sleeve portion <NUM> of the forked yoke <NUM>. Adjustment of the eccentric bearing <NUM> changes the angular amplitude of oscillation C from a first angular amplitude of oscillation C1 associated with a first position (<FIG>) of the eccentric bearing <NUM> to a second angular amplitude of oscillation C2 associated with a second position (<FIG>) of the eccentric bearing <NUM>. For example, the first angular amplitude of oscillation C1 may be about <NUM> degrees (e.g., +/- <NUM> degrees) and the second angular amplitude of oscillation C2 may be about <NUM> degrees (e.g., +/- <NUM> degrees). In some implementations, the first angular amplitude of oscillation C1 is <NUM> degrees and the second angular amplitude of oscillation C2 is <NUM> degrees. In other implementations, other suitable angles may be employed. For example, the first angle C1 may be greater than <NUM> degrees and less than <NUM> degrees, and the second angle C2 may be greater than or equal to <NUM> degree and less than <NUM> degrees. The second angular amplitude of oscillation C2 is greater than the first angular amplitude of oscillation C1. As the eccentric bearing <NUM> gets closer to the oscillation axis B, the angular amplitude of oscillation C increases. Conversely, as the eccentric bearing <NUM> gets farther away from the oscillation axis B, the angular amplitude of oscillation C decreases.

The first position (<FIG>) of the eccentric bearing <NUM> may be a minimum and the second position (<FIG>) of the eccentric bearing <NUM> may be a maximum such that the output (i.e., the angular amplitude of oscillation C) is adjustable between the first angular amplitude of oscillation C1 and the second angular amplitude of oscillation C2. In other words, the first and second positions may be extremes, and the eccentric bearing <NUM> is infinitely adjustable between extremes. The output may be infinitely adjustable between the first and second angles of oscillation C1, C2. For example, the eccentric bearing <NUM> may be infinitely adjustable between the first and second positions such that the angular amplitude of oscillation C is infinitely adjustable between (and including) the first and second angles of oscillation C1, C2. In this example, the eccentric bearing <NUM> may be fitted onto the eccentric shaft <NUM> slidably, employing a friction fit defined as tight enough such that the friction between the eccentric bearing <NUM> and the eccentric shaft <NUM> is sufficient to hold the eccentric bearing <NUM> in place on the eccentric shaft <NUM> in any position (i.e., a desired position) from the first position to the second position. However, there is enough give to allow movement of the eccentric bearing <NUM> on the eccentric shaft <NUM> in response to application of a manual force by the operator, as will be described in greater detail below. In other implementations, the eccentric bearing <NUM> and the eccentric shaft <NUM> may be movable as a unit in the horizontal direction H.

With reference to <FIG>, the power tool <NUM> also includes an amplitude adjustment actuator <NUM> (which may also be referred to as an angle adjustment actuator) operable by the operator to change the angular amplitude of oscillation C. The amplitude adjustment actuator <NUM> includes a first actuator portion 74a and a second actuator portion 74b, though the first and second actuator portions 74a, 74b may be formed as a single piece in other implementations. The first and second actuator portions 74a, 74b are symmetrically disposed on opposite sides of a plane <NUM> (<FIG>) defined as including the motor axis A and being parallel to the oscillation axis B. Each of the first and second actuator portions 74a, 74b includes an actuation surface 78a, 78b external to the housing <NUM> for engagement by an operator's hand to apply manual force to move the actuation surface 78a, 78b with respect to the housing <NUM>. The first actuation surface 78a extends through a first aperture 79a (<FIG>) in the housing <NUM> and the second actuation surface 78b extends through a second aperture 79b in the housing <NUM>. The first and second actuation surfaces 78a, 78b are disposed on opposite sides of the housing <NUM>, e.g., on opposite sides of the plane <NUM>, which divides the housing <NUM> into two substantially equal portions. An axis D extends from the first actuation surface 78a to the second actuation surface 78b surface in a direction generally perpendicular to both the oscillation axis B and the motor axis A. The amplitude adjustment actuator <NUM> may be generally elongated in the direction of the axis D.

Each of the first and second actuator portions 74a, 74b also includes a bearing fork 80a, 80b for receiving the eccentric bearing <NUM>. The bearing forks 80a, 80b define a receptacle <NUM> for receiving the eccentric bearing <NUM>. Each bearing fork 80a, 80b includes front bearing fork arms 84a, 84b disposed adjacent a front surface <NUM> (<FIG>) of the eccentric bearing <NUM> and rear bearing fork arms 88a, 88b disposed adjacent a rear surface <NUM> of the eccentric bearing <NUM>. The front surface <NUM> of the eccentric bearing <NUM> is disposed closer to the sleeve portion <NUM> in the horizontal direction H than the rear surface <NUM>, and the rear surface <NUM> is generally opposite the front surface <NUM> and farther from the sleeve portion <NUM> in the horizontal direction H than the front surface <NUM>. The receptacle <NUM> is disposed between the front and rear bearing fork arms 84a, 84b, 88a, 88b. The bearing forks 80a, 80b also define a side aperture <NUM> in communication with the receptacle <NUM> for receiving the forked yoke arms 64a, 64b and the eccentric shaft <NUM> in the receptacle <NUM>.

<FIG> are rear and front exploded views of the eccentric bearing <NUM> and the amplitude adjustment actuator <NUM>, showing more detail. A set of three orthogonal reference planes intersect each other at a geometric center E of the eccentric member <NUM>. The set of three orthogonal reference planes includes a first plane <NUM> and a second plane <NUM> together defining four substantially equal quadrants 110a, 112a, 114a, 116a (<FIG>) on the front surface <NUM> and four substantially equal corresponding quadrants 110b, 112b, 114b, 116b (<FIG>) on the rear surface <NUM> of the eccentric member <NUM>. The set of three orthogonal reference planes also includes a third plane <NUM> separating the front surface <NUM> from the rear surface <NUM>. The amplitude adjustment actuator <NUM> may engage the eccentric member <NUM> on the front surface <NUM> and on the rear surface <NUM>. The amplitude adjustment actuator <NUM> may also engage the eccentric member <NUM> on both sides of the first plane <NUM> and on both sides of the second plane <NUM> on the front surface <NUM> and/or on the rear surface <NUM>. For example, the first actuator portion 74a may engage the eccentric bearing <NUM> on a first side <NUM> of the first plane <NUM> and the second actuator portion 74b may engage the eccentric bearing <NUM> on a second side <NUM> of the first plane <NUM>. The bearing fork 80a of the first actuator portion 74a may engage both sides of the second plane <NUM> and both the front and rear surfaces <NUM>, <NUM>. The bearing fork 80b of the second actuator portion 74b may engage both sides of the second plane <NUM> and both the front and rear surfaces <NUM>, <NUM>. Thus, the eccentric bearing <NUM> is symmetrically engaged, and thus evenly pushed, by the amplitude adjustment actuator <NUM>. Even engagement provides a balanced force for moving the eccentric bearing <NUM> to facilitate smooth movement. For example, even engagement reduces the chance of a torque being applied causing the eccentric bearing <NUM> to bite or stick during application of the force.

The amplitude adjustment actuator <NUM> is slidable parallel to the axis A (in the horizontal direction H) to adjust the horizontal position of the eccentric bearing <NUM> with respect to the forked yoke <NUM>. During adjustment, the amplitude adjustment actuator <NUM> engages the rear surface <NUM> or front surface <NUM> of the eccentric bearing <NUM> to move the eccentric member <NUM> in the horizontal direction H closer to or farther from the sleeve portion <NUM> of the forked yoke <NUM>, respectively. As shown from <FIG>, this adjustment changes the angular amplitude of oscillation C within a range of angles from C1 to C2, inclusive thereof. Thus, the amplitude adjustment actuator <NUM> and the eccentric bearing <NUM> are infinitely adjustable between the first position (<FIG>) and the second position (<FIG>). The friction keeping the eccentric bearing <NUM> in place (as described above) may be enough to keep the amplitude adjustment actuator <NUM> in the desired position. In other implementations, the amplitude adjustment actuator <NUM> may have a frictional engagement with a portion of the power tool <NUM>, such as the housing <NUM>, in order to hold the amplitude adjustment actuator <NUM> and in turn the eccentric bearing <NUM> in the desired position. In some implementations, both the eccentric bearing <NUM> and the amplitude adjustment actuator <NUM> have frictional engagements.

In operation, the operator actuates the amplitude adjustment actuator <NUM> by manually engaging and pushing one or both of the actuation surfaces 78a, 78b in the horizontal direction H to select a desired angular amplitude of oscillation C between (and including) the first angular amplitude of oscillation C1 and the second angular amplitude of oscillation C2. Moving the amplitude adjustment actuator <NUM> closer to the oscillation axis B increases the angular amplitude of oscillation C and moving the amplitude adjustment actuator <NUM> farther away from the oscillation axis B decreases the angular amplitude of oscillation C. The operator actuates the power actuator <NUM> to engage the motor <NUM>, to oscillate the accessory <NUM> at the desired angular amplitude of oscillation C, and perform a cut or other operation. In some implementations, the operator may move the amplitude adjustment actuator <NUM> while the motor <NUM> is running and not running to change the angular amplitude of oscillation C during operation. In other implementations, the amplitude adjustment actuator <NUM> may be locked while the motor is running such that the operator can only move the amplitude adjustment actuator <NUM> when the motor <NUM> is not running.

Thus, the embodiments provide a power tool having an angle adjustment mechanism for infinitely adjusting the angular amplitude of oscillation C of the accessory holder <NUM> between a minimum angle C1 and a maximum angle C2.

Claim 1:
An oscillating power tool (<NUM>) comprising:
a housing (<NUM>);
a motor (<NUM>) disposed generally within the housing, the motor including a drive shaft (<NUM>) rotatable about a motor axis (A);
an output spindle (<NUM>) configured to be driven by the motor and journaled for oscillating rotation about an oscillation axis (B);
a drive mechanism (<NUM>) configured to convert rotation of the drive shaft into oscillating rotation of the output spindle about the oscillation axis, the drive mechanism including an eccentric member (<NUM>, <NUM>) configured to rotate off center about the motor axis, and a forked member (<NUM>) operatively coupled to the eccentric member and configured for oscillating rotation about the oscillation axis in response to rotation of the eccentric member,
wherein oscillating rotation of the forked member has an angular amplitude about the oscillation axis, wherein the eccentric member is movable with respect to the forked member to change the angular amplitude of oscillating rotation of the forked member, wherein the eccentric member includes a front surface (<NUM>) and a rear surface (<NUM>) opposite the front surface, wherein the front surface is closer to the output spindle than the rear surface, wherein the rear surface is closer to the motor than the front surface, wherein a set of three orthogonal reference planes (<NUM>, <NUM>, <NUM>) intersect each other at a geometric center (E) of the eccentric member, the set of three orthogonal reference planes including first and second planes (<NUM>, <NUM>) defining four substantially equal quadrants (110b, 112b, 114b, 116b) on the front and rear surfaces of the eccentric member and a third plane (<NUM>) separating the front surface from the rear surface; and
an amplitude adjustment actuator (<NUM>) configured to move the eccentric member to change the angular amplitude of oscillating rotation of the forked member, wherein the amplitude adjustment actuator is configured to engage the eccentric member on the front surface and on the rear surface,
wherein the oscillating power tool (<NUM>) is characterized in that the amplitude adjustment actuator is configured to engage the eccentric member on both sides of the first plane, and wherein the amplitude adjustment actuator is configured to engage the eccentric member on both sides of the second plane.