Patent Description:
The present invention relates to ratchet tools, and more particularly to powered ratcheting tools.

Powered ratchet tools sometimes allow an operator to drive an output member in a forward direction or an opposite reverse direction to apply torque to a fastener for tightening or loosening the fastener. Powered ratchet tools are typically powered by an electrical source, such as a DC battery, a conventional AC source, or pressurized air. Powered ratchet tools are constructed of components such as a drive mechanism including a motor and an output member for applying torque to the fastener.

According to its opening statement, <CIT> describes a power wrench that comprises a universally adjustable wrench having a head member of small compass, but yet of high strength to provide a socket retaining member which is light in weight but yet capable of withstanding the unusually high stresses to which, as above mentioned, this type of tool is often subjected. The socket retaining member is rotatably driven by a ratchet and pawl drive means which coacts with the head member to mount and support the socket retaining member, as well as to reinforce the same in all positions thereof during use of the wrench.

According to its opening statement, <CIT> describes a power driven open-end ratcheting wrench.

According to its abstract, <CIT> describes a tightening device for tightening a pipe connection, the tightening device comprising a frame, a reciprocating member adapted to reciprocate between a first position and a second position relative to the frame by pivoting about a first axis of rotation, a socket member adapted for rotating a connector nut of a pipe connection, the socket member having an open side for enabling accessing a rotation axis of the socket member from a radial direction, and a drive coupling between the reciprocating member and the socket member. During use of the tightening device a reciprocating motion of the reciprocating member between the first position and the second position provides unidirectional rotation of the socket member in the first direction of rotation.

Aspects of the present invention are defined by the appended independent claim.

Described herein is a powered ratchet tool comprising a housing and an output member having an inner opening, an outer toothed surface, and an output member aperture extending through the outer toothed surface to the inner opening. The powered ratchet tool further comprises a drive mechanism for driving the output member. The drive mechanism includes a yoke in which the output member is arranged. The yoke has a yoke aperture. The powered ratchet tool further comprises a first pawl in the yoke that is biased toward the toothed surface of the output member and a second pawl in the yoke that is biased toward the toothed surface of the output member. When the output member is in a home position, the first pawl and the second pawl are engaged with the toothed surface of the output member and the output member aperture is aligned with the yoke aperture.

Also described herein is a powered ratchet tool that comprises a housing and an output member having an inner opening defining a longitudinal axis, an outer toothed surface, and an output member aperture extending through the outer toothed surface to the inner opening. The powered ratchet tool further comprises a drive mechanism for driving the output member. The drive mechanism includes a crank shaft defining a crank axis that is parallel to the longitudinal axis and a yoke in which the output member is arranged. The yoke has a yoke aperture. The powered ratchet tool further comprises a first pawl in the yoke that is biased toward the toothed surface of the output member and a second pawl in the yoke that is biased toward the toothed surface of the output member. When the output member is in a home position, the first pawl and the second pawl are engaged with the toothed surface of the output member and the output member aperture is aligned with the yoke aperture.

Also described herein is a powered ratchet tool comprising a housing having a housing aperture and an output member having an inner opening defining a longitudinal axis, an outer toothed surface, and an output member aperture extending through the outer toothed surface to the inner opening. The powered ratchet tool further comprises a drive mechanism for driving the output member. The drive mechanism includes a drive shaft defining a drive axis that is perpendicular to the longitudinal axis, a drive gear to transmit torque to the output member, and a transmission configured to transmit torque from the crank shaft to the drive gear. When the output member is in a home position, the output member aperture is aligned with the housing aperture.

A shown in <FIG>, a powered ratchet tool <NUM> includes a housing <NUM> and a drive mechanism <NUM> for driving an output member <NUM>, such as a socket driver used to tighten or loosen fasteners (e.g., nuts or bolts). As shown in <FIG>, the drive mechanism <NUM> includes a motor <NUM> and a transmission <NUM> terminating in a crankshaft <NUM> having a drive bushing <NUM> arranged eccentrically on an end <NUM> of the crankshaft <NUM>. The motor <NUM> is powered by a removable and rechargeable battery pack <NUM>. The drive mechanism <NUM> also includes a yoke <NUM> through which the output member <NUM> extends. The yoke <NUM> has a recess <NUM> (<FIG>) in which the drive bushing <NUM> is arranged and a yoke aperture <NUM> giving the yoke <NUM> a C-shape. As explained in further detail below, when the crankshaft <NUM> rotates, the drive bushing <NUM> pivots the yoke <NUM> in a reciprocating manner, relative to the housing <NUM>, to drive the output member <NUM>.

With reference to <FIG>, the ratchet tool <NUM> also includes a first pawl <NUM> and a second pawl <NUM> in the yoke <NUM>. The first and second pawls <NUM>, <NUM> are biased by first and second springs <NUM>, <NUM>, respectively, toward an outer toothed surface <NUM> of the output member <NUM>. The output member <NUM> also has an inner opening <NUM> defining a longitudinal axis <NUM>. The inner opening <NUM> includes a first end section <NUM> with a first size and a first shape, such as a <NUM>-point double hexagon shape, and a second end section <NUM> with a second size and a second shape. In the illustrated embodiment, the second size is larger than the first size and the second shape is also a <NUM>-point double hexagon shape, but in other embodiments, the second size can be smaller and the second shape can be different than the first shape. The first end section <NUM> is configured to receive a fastener or an insert having a corresponding shape and size. Likewise, the second end section <NUM> is configured to receive a fastener or an insert having a corresponding shape and size. In some embodiments, the first size is the same as the second size and the first shape is the same as the second shape.

With reference to <FIG>, the output member <NUM> also includes an output member aperture <NUM> extending through the outer toothed surface <NUM> to the inner opening <NUM>. As shown in <FIG>, when the output member <NUM> is in a "home" position, the output member aperture <NUM> is aligned with the yoke aperture <NUM>, creating a passage allowing a fastener or nut to be moved horizontally (i.e., transverse to the axis <NUM>) through the apertures <NUM>, <NUM> and into the inner opening <NUM> of the output member <NUM>. In some embodiments, the output member <NUM> includes a magnet <NUM> (<FIG>) that is detectable by a sensor <NUM> on the housing <NUM> of the ratchet tool <NUM>, such as a Hall-effect sensor, when the output member <NUM> is in the home position.

As shown in <FIG>, the ratchet tool <NUM> includes a first actuator <NUM> in communication with a controller <NUM>. In some embodiments, the ratchet tool <NUM> includes a second actuator <NUM> in communication with the controller <NUM>. The controller <NUM> is in communication with the motor <NUM> and is thus configured to activate and deactivate the drive mechanism <NUM>, as explained in further detail below.

In operation, with the output member <NUM> in the home position, when an operator wishes to loosen a fastener or nut in a hard to reach location, such as a vertically narrow crevice, the operator moves the tool <NUM> horizontally into the crevice such that the shank of the fastener to which the nut or fastener head is attached passes through yoke aperture <NUM> and the output member aperture <NUM>, and into the inner opening <NUM>. Once the shank is received in the inner opening <NUM> and aligned with the longitudinal axis <NUM>, the operator moves the output member <NUM> along the longitudinal axis <NUM> and the shank until the second end section <NUM> engages the nut or fastener head. The operator then actuates and holds the first actuator <NUM> and in response, the controller <NUM> activates the motor <NUM> of the drive mechanism <NUM>, causing the crankshaft <NUM> to rotate the drive bushing <NUM>, which causes the yoke <NUM> to pivot in a reciprocating manner relative to the housing <NUM>.

Initially, as the yoke <NUM> is undergoing a "driving" pivot motion (pivoting counterclockwise as viewed in <FIG> about the longitudinal axis <NUM>), both the first pawl <NUM> and second pawl <NUM> engage the toothed surface <NUM> of the output member <NUM>. Thus, torque is transferred from the yoke <NUM> to the output member <NUM> by both the first and second pawls <NUM>, <NUM>, causing the output member <NUM> to rotate counterclockwise about the longitudinal axis <NUM>, as viewed in <FIG>. As the crankshaft <NUM> continues to rotate the drive bushing <NUM>, the yoke <NUM> undergoes a "ratcheting" pivot motion (pivoting clockwise as viewed in <FIG> about the longitudinal axis <NUM>), causing the first pawl <NUM> and the second pawl <NUM> to ratchet back across the toothed surface <NUM> of the output member <NUM>, thus not transferring any torque to the output member <NUM>. After completing the "ratcheting" pivot motion, the yoke <NUM> continues to perform a series of subsequent "driving" and "ratcheting" pivot motions to loosen the fastener or nut via the output member <NUM>.

Eventually the output member <NUM> is rotated to a second position shown in <FIG>, in which the output member aperture <NUM> is aligned with the first pawl <NUM>. While the output member <NUM> is in the second position, the first pawl <NUM> is not engaged with toothed surface <NUM> and thus cannot transfer any torque to the output member <NUM> during a "driving" pivot motion of the yoke <NUM>. However, while the output member <NUM> is in the second position, the second pawl <NUM> is engaged with the toothed surface <NUM> and thus is able to transfer torque to the output member <NUM> during a "driving" pivot motion of the yoke.

Subsequently, the output member <NUM> is rotated to a third position shown in <FIG>, in which the output member aperture <NUM> is aligned with the second pawl <NUM>. While output member <NUM> is in the third position, the second pawl <NUM> is not engaged with toothed surface <NUM> and thus cannot transfer any torque to the output member <NUM> during a "driving" pivot motion of the yoke <NUM>. However, while the output member <NUM> is in the third position, the first pawl <NUM> is engaged with the toothed surface <NUM> and thus is able to transfer torque to the output member <NUM> during a "driving" pivot motion of the yoke. Once the fastener or nut has been loosened, the operator may remove the tool <NUM> from the fastener and release the first actuator <NUM>.

In some embodiments, after releasing the first actuator <NUM>, the controller <NUM> recognizes that the output member <NUM> is not in the home position because the magnet <NUM> is not detected by the sensor <NUM>. Thus, in response to recognizing the output member <NUM> is not in the home position, despite the first actuator <NUM> being released by the operator, the controller <NUM> maintains the drive mechanism <NUM> in an activated state to continue rotating the output member <NUM>, as described above, until the output member <NUM> is in the home position. When the output member <NUM> reaches the home position, the sensor <NUM> detects the magnet <NUM> and in response, the controller <NUM> deactivates the drive mechanism <NUM>.

In other embodiments, after releasing the first actuator <NUM>, the drive mechanism <NUM> is deactivated <NUM>. The operator then actuates and holds the second actuator <NUM>. In response to actuation of the second actuator <NUM>, the controller <NUM> first determines whether the output member <NUM> is in the home position by determining whether the sensor <NUM> detects the magnet <NUM>. If the controller <NUM> determines the output member <NUM> is not in the home position, the controller <NUM> activates the drive mechanism <NUM> to continue rotating the output member <NUM> until the output member <NUM> is in the home position. When the output member <NUM> reaches the home position, the sensor <NUM> detects the magnet <NUM> and in response, the controller <NUM> deactivates the drive mechanism <NUM>, even if the operator continues to hold the second actuator <NUM>. Thereafter, the operator releases the second actuator <NUM>.

In operation, when an operator wishes to tighten a fastener or nut, the operator must vertically flip the tool <NUM>, such that the first end section <NUM> can engage the fastener or nut. The operator may then actuate and hold the first actuator <NUM> as described above until the fastener or nut has been tightened.

<FIG> illustrate another embodiment of a powered ratchet tool <NUM> including a housing <NUM>, a drive mechanism <NUM> for driving an output member <NUM>, such as a socket driver used to tighten or loosen fasteners (e.g., nuts or bolts). As shown in <FIG>, the drive mechanism <NUM> includes a motor <NUM> and a transmission <NUM> terminating in a crankshaft <NUM> defining a crank axis <NUM>. The motor <NUM> is powered by a removable and rechargeable battery pack <NUM>. An eccentric <NUM> is eccentrically arranged on the crankshaft <NUM> and extends into a drive bushing <NUM>. The drive mechanism <NUM> also includes a yoke <NUM> through which the output member <NUM> extends. The yoke <NUM> has parallel arms <NUM> (<FIG>). Between the arms <NUM>, a recess <NUM> is defined in which the drive bushing <NUM> is arranged. The yoke <NUM> also includes a yoke aperture <NUM> giving the yoke <NUM> a C-shape. As explained in further detail below, when the crankshaft <NUM> rotates, the drive bushing <NUM> pivots the yoke <NUM> in a reciprocating manner, relative to the housing <NUM>, to drive the output member <NUM>.

With reference to <FIG>, the ratchet tool <NUM> also includes a first pawl <NUM> and a second pawl <NUM> in the yoke <NUM>. The first and second pawls <NUM>, <NUM> are biased by first and second springs <NUM>, <NUM>, respectively, toward an outer toothed surface <NUM> of the output member <NUM>. The output member <NUM> also has an inner opening <NUM> defining a longitudinal axis <NUM> that is parallel to the crank axis <NUM>. The inner opening <NUM> is similar to the inner opening <NUM> of ratchet tool <NUM>. The output member <NUM> also includes an output member aperture <NUM> extending through the outer toothed surface <NUM> to the inner opening <NUM>. As shown in <FIG>, when the output member is in a "home" position, the output member aperture <NUM> is aligned with the yoke aperture <NUM>, creating a passage allowing the shank of a fastener to which a nut or fastener head is attached to be moved through the apertures <NUM>, <NUM> and into the inner opening <NUM> of the output member <NUM>.

Like the ratchet tool <NUM>, in some embodiments, the output member <NUM> includes a magnet that is detectable by a sensor on the housing <NUM> of the ratchet tool <NUM>, such as a Hall-effect sensor, when the output member <NUM> is in the home position. Like the ratchet tool <NUM>, in some embodiments, the ratchet tool <NUM> includes a first actuator <NUM>, a second actuator <NUM>, and a controller that have the same functions as the first actuator <NUM>, second actuator <NUM> and controller <NUM> of the ratchet tool <NUM>. The magnet, sensor, first actuator <NUM>, second actuator <NUM>, and controller of the ratchet tool <NUM> can all work together in the same way as described above with the ratchet tool <NUM>.

The ratchet tool <NUM> is operable in the same manner as the ratchet tool <NUM>, except for the following differences explained below. When the drive mechanism <NUM> is activated, the crankshaft <NUM> rotates about the crank axis <NUM>, causing the eccentric <NUM> to rotate about the crank axis <NUM> in a manner that eccentrically drives the drive bushing <NUM> within the recess <NUM> of the yoke <NUM>. Specifically, in response to the driving motion of the eccentric <NUM>, the drive bushing <NUM> has two orthogonal components of motion, along a first axis <NUM> that is parallel to the two arms <NUM> and intersects the crank axis <NUM> and longitudinal axis <NUM>, and along a second axis <NUM> that is perpendicular to the first axis <NUM>. As shown in <FIG>, the crank axis <NUM> does not intersect the second axis <NUM>. As the eccentric <NUM> is rotated, movement is imparted to the drive bushing <NUM> having components along both of the first and second axes <NUM>, <NUM>. The component of the bushing's motion along the first axis <NUM> does not apply a moment to the yoke <NUM>. However, the component of the bushing's motion along the second axis <NUM> alternatively contacts one of the two arms <NUM>, thus causing the yoke <NUM> to pivot in a reciprocating manner about the longitudinal axis <NUM> and relative to the housing <NUM>, thus driving the output member <NUM> in a similar manner to the yoke <NUM> driving the output member <NUM> of the ratchet tool <NUM>.

<FIG> illustrate another embodiment of a powered ratchet tool <NUM> including a housing <NUM> and a drive mechanism <NUM> for driving an output member <NUM>, such as a socket driver used to tighten or loosen fasteners (e.g., nuts or bolts). As shown in <FIG>, the drive mechanism <NUM> includes a motor <NUM> having a drive axis <NUM> and a transmission <NUM>. The transmission <NUM> includes a first gear <NUM>, such as a bevel gear, a second gear <NUM>, such as another bevel gear, and a drive gear <NUM> to drive the output member <NUM>. Specifically, the drive gear <NUM> has teeth <NUM> that are engaged with a driven ring <NUM> of the output member <NUM>. Unlike the powered ratchet tools <NUM>, <NUM>, the powered ratchet tool <NUM> does not include a ratchet mechanism. The drive gear <NUM> drives the output member <NUM> in a tightening or loosening direction depending on the rotational direction of the motor <NUM>. The motor <NUM> is powered by a removable and rechargeable battery pack <NUM>. The output member <NUM> has an output aperture <NUM> and the housing <NUM> has a housing aperture <NUM>, giving both a C-shape. When the output aperture <NUM> is aligned with the housing aperture <NUM>, the output member <NUM> is in the home position.

Like the ratchet tools <NUM> and <NUM>, in some embodiments, the output member <NUM> includes a magnet <NUM> that is detectable by a sensor <NUM> on the housing <NUM> of the ratchet tool <NUM>, such as a Hall-effect sensor, when the output member <NUM> is in the home position. Like the ratchet tools <NUM> and <NUM>, in some embodiments, the ratchet tool <NUM> includes a first actuator <NUM>, a second actuator <NUM>, and a controller <NUM> that have the same functions as the first actuators <NUM>, <NUM>, second actuator <NUM>, <NUM> and controllers of the ratchet tools <NUM>, <NUM>. The magnet <NUM>, sensor <NUM>, first actuator <NUM>, second actuator <NUM>, and controller <NUM> of the ratchet tool <NUM> can all work together in the same way as described above with the ratchet tools <NUM>, <NUM>.

Claim 1:
A powered ratchet tool (<NUM>, <NUM>, <NUM>) comprising:
a housing (<NUM>, <NUM>, <NUM>);
an output member (<NUM>, <NUM>, <NUM>) having an inner opening (<NUM>, <NUM>), an outer toothed surface (<NUM>, <NUM>), and an output member aperture (<NUM>, <NUM>, <NUM>) extending through the outer toothed surface to the inner opening;
a drive mechanism (<NUM>, <NUM>, <NUM>) for driving the output member, the drive mechanism including a yoke (<NUM>, <NUM>) in which the output member is arranged, the yoke having a yoke aperture (<NUM>, <NUM>);
a first pawl (<NUM>, <NUM>) in the yoke that is biased toward the toothed surface of the output member; and
a second pawl (<NUM>, <NUM>) in the yoke that is biased toward the toothed surface of the output member;
wherein when the output member is in a home position, the first pawl and the second pawl are engaged with the toothed surface of the output member and the output member aperture is aligned with the yoke aperture;
a first actuator (<NUM>, <NUM>, <NUM>) configured to activate the drive mechanism when the first actuator is actuated; and
a controller (<NUM>, <NUM>) configured to activate and deactivate the drive mechanism, wherein upon actuation and release of the first actuator, if the output member is not in the home position, the controller is configured to activate the drive mechanism until the output member has been driven to the home position.