Patent Description:
The present invention relates to power tools, and more particularly to pipe fitting tools.

Pipe fitting tools are used to connect and disconnect pipes, which often use threaded joints to connect to each other. A tool according to the preamble of claim <NUM> is disclosed in document <CIT>.

The present invention provides, in one aspect, a pipe fitting tool configured to loosen a first section of pipe with respect to a second section of pipe. The pipe fitting tool includes a motor, a reciprocating member that reciprocates in response to activation of the motor, a holdback assembly configured to clamp and hold the second section of pipe, and a loosening mechanism configured to clamp and rotate the first section of pipe with respect to the second section of pipe in response to a first linear motion of the reciprocating member, and to release the first section of pipe in response to a second linear motion of the reciprocating member, the second linear motion being in a direction opposite the first linear motion.

In some embodiments, the pipe fitting tool includes a housing containing the motor and a battery removably coupled to the housing. The battery is configured to provide power to the motor.

In some embodiments, the holdback assembly includes a first pair of jaws, and the loosening mechanism includes a second pair of jaws.

In some embodiments, the holdback assembly is adjustably positioned relative to the loosening mechanism.

In some embodiments, the loosening mechanism includes a screw rotatably driven by the motor to clamp and rotate the first section of pipe.

The present invention provides, in another aspect, a pipe fitting tool configured to loosen a first section of pipe with respect to a second section of pipe. The pipe fitting tool includes a motor, a lead screw configured to rotate in response to receiving torque from the motor, a carriage configured to move along the lead screw between a first position and a second position in response to rotation of the lead screw, a holdback assembly configured to clamp and hold the second section of pipe, and a jaw assembly. The jaw assembly is configured to clamp and rotate the first section of pipe with respect to the second section of pipe in response to movement of the carriage from the first position to the second position, and to release the first section of pipe in response to movement of the carriage from the second position to the first position.

In some embodiments, the holdback assembly includes a first jaw and a second jaw movable relative to the first jaw.

In some embodiments, the holdback assembly includes a handle, and a spacing between the first jaw and the second jaw is decreased in response to movement of the handle to clamp and hold the second section of pipe.

In some embodiments, the holdback assembly includes a drive shaft coupled to the handle and a pinion coupled for co-rotation with the drive shaft, and the drive shaft is configured to rotate in response to movement of the handle.

In some embodiments, the holdback assembly includes a first rack gear meshed with the pinion and coupled to the first jaw and a second rack gear meshed with the pinion and coupled to the second jaw such that rotation of the pinion causes the first and second jaws to move in opposite directions.

In some embodiments, the pipe fitting tool includes a removable battery configured to power the motor.

In some embodiments, the jaw assembly includes a first jaw and a second jaw movable relative to the first jaw, and the first jaw is biased toward the second jaw.

In some embodiments, the holdback assembly is adjustably positionable relative to the jaw assembly.

In some embodiments, the holdback assembly includes a track to guide movement of the jaw assembly relative to the holdback assembly.

In some embodiments, the pipe fitting tool includes a post extending parallel to the lead screw, and the carriage includes a sleeve slidable along the post to guide movement of the carriage.

In some embodiments, the motor includes an output shaft extending parallel to the lead screw.

The present invention provides, in another aspect, a method of loosening a first section of pipe with respect to a second section of pipe, including positioning first and second jaws of a holdback assembly on opposite sides of the second section of pipe, positioning third and fourth jaws of a drive assembly on opposite sides of the first section of pipe, rotating a handle of the holdback assembly in a tightening direction to clamp the second section of pipe between the first and second jaws, and performing a loosening operation including activating a motor of the drive assembly in a loosening direction to cause the third and fourth jaws to clamp the first section of pipe between the third and fourth jaws and continuing to operate the motor in the loosening direction to cause the third and fourth jaws to rotate the first section of pipe relative to the second section of pipe.

In some embodiments, the method includes performing a resetting operation after the loosening operation, the resetting operation including reversing an operating direction of the motor to cause the third and fourth jaws to release the first section of pipe.

In some embodiments, the method includes repeating the loosening operation after the resetting operation.

In some embodiments, rotating the handle of the holdback assembly includes rotating a pinion meshed with a first rack coupled to the first jaw and a second rack coupled to the second jaw.

<FIG> illustrate a pipe fitting apparatus <NUM> according to one embodiment. The pipe fitting apparatus <NUM> includes a drive member <NUM> and a plurality of circumferential clamping members <NUM> that are coupled to the drive member <NUM> and configured to surround and apply a radial clamping force to a first section of pipe <NUM>, in order to loosen the first section of pipe <NUM> relative to a second section of pipe <NUM>, as described in further detail below. The clamping members <NUM> are initially biased toward each other by an internal biasing mechanism (not shown), prior to the operation beginning. The drive member <NUM> includes an aperture <NUM> to receive, e.g., a bit of a rotary power tool <NUM>, such as an impact driver or drill-driver.

In operation, the clamping members <NUM> are slid axially over an end <NUM> of the first section of pipe <NUM> and retained on the first section of pipe <NUM> via the internal biasing mechanism. The bit of the rotary power tool is then inserted into the aperture <NUM>, which keys to the bit so as to transfer torque from the bit to the drive member <NUM>. The operator then activates the power tool <NUM> to rotate the bit, thus rotating the drive member <NUM>.

Rotation of the drive member <NUM> causes the clamping members <NUM> to cam towards each other and rotate with the drive member <NUM>, thus applying a radial clamping force on the first section of pipe <NUM>. With the first section of pipe <NUM> now clamped to the drive member <NUM>, the rotation of the drive member <NUM> causes the first section of pipe <NUM> to rotate with respect to the second section of pipe <NUM> (which is fixed in place, such as by a pipe clamp), thus allowing the first section of pipe <NUM> to be loosened with respect to and removed from the second section of pipe <NUM>. In some embodiments, the diameter between the clamping members <NUM> is increased or decreased to accommodate pipes of different diameters. The pipe fitting apparatus <NUM> advantageously allows an operator to leverage the existing power tool <NUM> to loosen and/or remove the first section of pipe <NUM>, and to maintain the interior threading of the first section of pipe <NUM>. However, in some embodiments, the pipe fitting apparatus <NUM> may be integrated with the power tool <NUM>.

<FIG> illustrate a pipe fitting assembly <NUM> according to another embodiment and including a first pipe wrench <NUM>, a second pipe wrench <NUM>, and a tensioning mechanism <NUM> extending between and interconnecting the first and second pipe wrenches <NUM>, <NUM>. In the embodiment illustrated in <FIG> and <FIG>, the tensioning mechanism <NUM> includes a turnbuckle <NUM> with a first, right-hand threaded rod <NUM> having a first end <NUM> coupled to an end <NUM> of the first pipe wrench <NUM>, and a second, left-hand threaded rod <NUM> having a second end <NUM> coupled to an end <NUM> of the second pipe wrench <NUM>. In the illustrated embodiment, the first and second ends <NUM>, <NUM> each include a C-clip with a pin to respectively couple to the ends <NUM>, <NUM> of the first and second pipe wrenches <NUM>, <NUM>.

The first and second threaded rods <NUM>, <NUM> of the turnbuckle <NUM> are threadably coupled to a body piece <NUM> (<FIG>). In operation, a clamping end <NUM> of the first pipe wrench <NUM> is clamped on a first section of pipe <NUM>, and a clamping end <NUM> of the second pipe wrench <NUM> is clamped on a second section of pipe <NUM>, as shown in <FIG>. The body piece <NUM> is then rotated, causing the first and second threaded rods <NUM>, <NUM> to move toward each other. As the first and second threaded rods <NUM>, <NUM> move toward each other, the end <NUM> of the first pipe wrench <NUM> is moved toward the end <NUM> of the second pipe wrench <NUM>, and thus the first pipe section <NUM> is loosened with respect to the second section of pipe <NUM>.

<FIG> illustrates another embodiment of the pipe fitting assembly <NUM>, with the turnbuckle <NUM> of the tensioning mechanism <NUM> replaced by a winch <NUM> coupled to the end <NUM> of the first pipe wrench <NUM>, with a cable <NUM> of the winch <NUM> coupled to the end <NUM> of the second pipe wrench <NUM>. In operation, the clamping end <NUM> of the first pipe wrench <NUM> is clamped on the first section of pipe <NUM>, and the clamping end <NUM> of the second pipe wrench <NUM> is clamped on the second section of pipe <NUM>. The winch <NUM> is then used to retract the cable <NUM>, moving the end <NUM> of the first pipe wrench <NUM> toward the end <NUM> of the second pipe wrench <NUM>, thus loosening the first section of pipe <NUM> with respect to the second section of pipe <NUM>.

<FIG> illustrates a pipe fitting apparatus <NUM> according to another embodiment. The pipe fitting apparatus <NUM> includes a first pipe wrench <NUM> coupled to a first section of pipe <NUM> and a second pipe wrench <NUM> coupled to a second section of pipe (not shown). A pivoting linkage <NUM> couples the first pipe wrench <NUM> to the second pipe wrench <NUM>. The pipe fitting apparatus <NUM> further includes a motor <NUM> coupled to a first end <NUM> of the first pipe wrench <NUM>, and a chain <NUM> extending between the motor <NUM> and a second end <NUM> of the second pipe wrench <NUM>.

In operation, the operator clamps the first pipe wrench <NUM> on the first section of pipe <NUM> and the second pipe wrench <NUM> on the second section of pipe. The pivoting linkage <NUM> assists an operator during this setup process by maintaining the two wrenches <NUM>, <NUM> at a desired orientation. Specifically, while gravity allows the first pipe wrench <NUM> to be initially secured onto the first section of pipe and apply a moment thereto in a first rotational direction, the second pipe wrench <NUM> is secured onto the second section of pipe and initially applies a moment thereto in a second rotational direction that is opposite the first rotational direction, via the linkage <NUM>, which keeps the second pipe wrench <NUM> at a predetermined location with respect to the first pipe wrench <NUM>. The operator then activates the motor <NUM> to retract the chain <NUM>, thus pulling the first end <NUM> of the first pipe wrench <NUM> toward the second end <NUM> of the second pipe wrench <NUM>, thus loosening the first section of pipe <NUM> with respect to the second section of pipe. As the first end <NUM> moves toward the second end <NUM>, the pivoting linkage <NUM> closes in a scissor-like motion about a pivot point <NUM>.

<FIG> illustrates another embodiment of a pipe fitting apparatus 106a that is similar to the pipe fitting apparatus <NUM> described above with reference to <FIG>, with like parts having corresponding reference numerals appended with the letter "a," and differences explained below. Instead of an external motor <NUM> coupled to the first end 126a of the first pipe wrench 110a, the first pipe wrench 110a includes an internal motor 124a (shown schematically), and a battery <NUM> to provide power thereto. Also, the pivoting linkage <NUM> is omitted from the pipe fitting apparatus 106a.

<FIG> illustrates another embodiment of a pipe fitting apparatus 106b that is similar to the pipe fitting apparatus <NUM> described above with reference to <FIG>, with like parts having corresponding reference numerals appended with the letter "b," and differences explained below. Instead of a rigid, pivoting linkage <NUM>, the pipe fitting apparatus 106b includes a flexible linkage 122b. The flexible linkage 122b may include, for example, a cable made from steel, nylon, or any other suitable material connected to the respective pipe wrenches 110b, 114b. Instead of a motor <NUM> attached to the first end 126b of the first pipe wrench <NUM>, the motor 124b is arranged between the first and second ends 126b, 130b, with a first chain <NUM> coupled to the first end 126b and a second chain <NUM> coupled to the second end 130b. The motor <NUM> is operable to retract the chains <NUM>, <NUM> (which, in some embodiments, may be end portions of a single chain), to thereby move the first end 126b toward the second end 130b.

<FIG> illustrates a pipe fitting tool <NUM> according to another embodiment of the present disclosure and including a housing <NUM>, a motor <NUM> supported within the housing <NUM>, a transmission <NUM> (e.g., a planetary transmission) coupled to an output of the motor <NUM>, and a linear output member <NUM>, which may include a hydraulic or pneumatic piston driven via a pump coupled to an output of the transmission <NUM>, a power screw, or any other suitable mechanism, driven to move linearly along a longitudinal axis <NUM> of the housing <NUM> in response to activation of the motor <NUM>. The motor <NUM>, transmission <NUM>, and output member <NUM> are illustrated schematically in <FIG>, and it should be understood that these components may be arranged, supported, and interconnected in various ways. The illustrated pipe fitting tool <NUM> further includes a holdback assembly <NUM> configured to clamp and hold a second section of pipe <NUM>, and a pipe loosening mechanism <NUM> configured to loosen a first section of pipe <NUM> with respect to the second section of pipe <NUM> in response to reciprocation of the output member <NUM>, as explained in further detail below.

In the illustrated embodiment, a battery <NUM> (e.g., a removable power tool battery back having a nominal output voltage of <NUM> volts) provides power to the motor <NUM>. The holdback assembly <NUM> includes a frame <NUM> coupled to the housing <NUM> and having a static (i.e. fixed) first vice jaw <NUM>. In the illustrated embodiment, the frame <NUM> is fixed to the housing <NUM> but in other embodiments, the frame <NUM>, and thus the holdback assembly <NUM>, may be adjustable with respect to the housing <NUM>. A moveable second vice jaw <NUM> of the holdback assembly <NUM> is moveable with respect to the frame <NUM> via rotation of a screw <NUM> threaded through the frame <NUM>. The second vice jaw <NUM> is thereby able to move toward and away from the first vice jaw <NUM>, allowing the holdback assembly <NUM> to clamp and secure sections of pipes having different diameters.

As shown in <FIG>, the loosening mechanism <NUM> includes a linkage <NUM> having a slot <NUM> arranged obliquely with respect to an axis of reciprocation <NUM> of the output member <NUM>. The linkage <NUM> also includes a first clamping jaw <NUM> and a pivot point <NUM>. A second clamping jaw <NUM> is pivotally coupled to the first clamping jaw <NUM> via the pivot point <NUM>. In operation, the second section of pipe <NUM> is clamped between the first and second vice jaws <NUM>, <NUM> of the holdback assembly <NUM>, and the first section of pipe <NUM> is arranged between the first and second clamping jaws <NUM>, <NUM> of the loosening mechanism <NUM>. The motor <NUM> is then activated, causing reciprocation of the output member <NUM>. A crosswise pin <NUM> (<FIG>), coupled to the output member <NUM>, is arranged in the slot <NUM> of the linkage <NUM> and thus, in response to reciprocation of the output member <NUM>, the loosening mechanism <NUM> repeatedly undergoes two separate motions.

First, with reference to the orientation illustrated in <FIG>, as the output member <NUM> and crosswise pin <NUM> moves from left to right in an expanding motion, due to the arrangement of the crosswise pin <NUM> in the slot <NUM>, the linkage <NUM> is caused to pivot clockwise about a pivot point <NUM>, where the linkage <NUM> is pivotally coupled to a clevis <NUM> of the housing <NUM> (<FIG>). As the linkage <NUM> pivots clockwise, the second clamping jaw <NUM> is moved toward the first clamping jaw <NUM> by pivoting about the pivot point <NUM>, thus clamping the first section of pipe <NUM> and rotating it in a loosening direction with respect to the second section of pipe <NUM>.

Second, as the output member <NUM> and crosswise pin <NUM> move from right to left, in a retracting motion, the pin <NUM> bears against the slot <NUM> to cause the linkage <NUM> to pivot counterclockwise about the pivot point <NUM>. As the linkage <NUM> pivots counterclockwise, the second clamping jaw <NUM> is moved away from the first clamping jaw <NUM> by pivoting about the pivot point <NUM>, such that the clamping force on the first section of pipe <NUM> is released, and the first clamping jaw <NUM> rotates to a new position about the first section of pipe <NUM> in preparation for a subsequent loosening cycle. As the output member <NUM> continues to reciprocate and these two motions of the loosening mechanism <NUM> are incrementally repeated in continuous succession, the first section of pipe <NUM> is progressively loosened from the second section of pipe <NUM>.

<FIG> illustrates an alternative loosening mechanism <NUM>, which may be used with the pipe fitting tool <NUM> instead of loosening mechanism <NUM>. The loosening mechanism <NUM> includes a linkage <NUM>, a first clamping jaw <NUM> coupled to the linkage <NUM> via a crosswise pin <NUM>, and a second clamping jaw <NUM> coupled to the linkage <NUM> via a pin <NUM> in a slot <NUM> and rotatably coupled to the first clamping jaw <NUM> via a circular segment <NUM> in a circular recess <NUM>. As described below, in response to reciprocation of the output member <NUM>, the loosening mechanism <NUM> repeatedly undergoes two separate motions.

First, in the frame of reference of <FIG>, as the output member <NUM> and crosswise pin <NUM> moves from left to right in an expanding motion, due to the arrangement of the crosswise pin <NUM> in a slot <NUM> of the linkage <NUM>, the linkage <NUM> is caused to pivot clockwise about a pivot point <NUM> coupled to the housing <NUM>. As the linkage <NUM> pivots clockwise, the second clamping jaw <NUM> is pivoted towards the first clamping jaw <NUM> about a pivot point defined by the circular segment <NUM> and recess <NUM>, thus clamping the first section of pipe <NUM> between the jaws <NUM>, <NUM>. Once the first section of pipe <NUM> is clamped, further movement of the output member <NUM> from left to right causes the jaws <NUM>, <NUM> to rotate together in a clockwise direction, thereby rotating the first section of pipe <NUM> in a loosening direction with respect to the second section of pipe <NUM>.

Second, in the frame of reference of <FIG>, due to the arrangement of the crosswise pin <NUM> in the slot <NUM> of the linkage <NUM>, as the output member <NUM> and crosswise pin <NUM> move from right to left in a retracting motion, the linkage <NUM> is caused to pivot counterclockwise about the pivot point <NUM>, <NUM>. As the linkage <NUM> pivots counterclockwise, the second clamping jaw <NUM> is moved away from the first clamping jaw <NUM>, such that the clamping force on the first section of pipe <NUM> is released, such that the first section of pipe <NUM> is not rotated in a tightening direction with respect to the second section of pipe <NUM> during retraction of the crosswise pin <NUM>.

<FIG> illustrates an altemative loosening mechanism <NUM>, which may be used with the pipe fitting tool <NUM> instead of loosening mechanism <NUM>. The loosening mechanism <NUM> includes a linkage <NUM> and a first clamping jaw <NUM> translatable along a body <NUM> of a second clamping jaw <NUM>. An extension <NUM> of the linkage <NUM> is arranged in a notch <NUM> of the first clamping jaw <NUM>. The second clamping jaw <NUM> is pivotally coupled to the linkage <NUM>. In response to reciprocation of the output member <NUM>, the loosening mechanism <NUM> repeatedly undergoes two separate motions, as described below.

First, in the frame of reference of <FIG>, as the output member <NUM> and crosswise pin <NUM> move from left to right in an expanding motion, due to the arrangement of the crosswise pin <NUM> in a slot <NUM> of the linkage <NUM>, the linkage <NUM> is caused to pivot clockwise about a pivot point <NUM> coupled to the housing <NUM>. As the linkage <NUM> pivots clockwise, the body <NUM> of the second clamping jaw <NUM> pivots therewith and the first clamping jaw <NUM> moves downwards along the body <NUM> toward the second clamping jaw <NUM>, due to the extension <NUM> pushing the notch <NUM> in a downward direction. Once the first section of pipe <NUM> is clamped, further movement of the output member <NUM> from left to right causes the jaws <NUM>, <NUM> to rotate together in a clockwise direction, thereby rotating the first section of pipe <NUM> in a loosening direction with respect to the second section of pipe <NUM>. Thus, the first section of pipe <NUM> is clamped and rotated in a loosening direction it with respect to the second section of pipe <NUM>.

Second, in the frame of reference of <FIG>, as the output member <NUM> and crosswise pin <NUM> move from right to left in a retracting motion, due to the arrangement of the crosswise pin <NUM> in the slot <NUM> of the linkage <NUM>, the linkage <NUM> is caused to pivot counterclockwise about the pivot point <NUM>. As the linkage <NUM> pivots counterclockwise, the second clamping jaw <NUM> rotates therewith, and the first clamping jaw <NUM> moves along the body <NUM> away from the second clamping jaw <NUM>, due to the extension <NUM> pushing the notch <NUM> in an upward direction. Thus, the clamping force on the first section of pipe <NUM> is released, such that the first section of pipe <NUM> is not rotated in a tightening direction with respect to the second section of pipe <NUM> during retraction of the crosswise pin <NUM>.

<FIG> illustrates an alternative loosening mechanism <NUM>, which may be used with the pipe fitting tool <NUM> instead of loosening mechanism <NUM>. The loosening mechanism <NUM> includes a linkage <NUM> and a first clamping jaw <NUM> pivotable about a pivot point <NUM> at which the first clamping jaw <NUM> is pivotally coupled to the linkage <NUM>. The first clamping jaw <NUM> is also pivotably coupled to a second clamping jaw <NUM> at a pivot point <NUM>. In response to reciprocation of the output member <NUM>, the loosening mechanism <NUM> repeatedly undergoes two separate motions, as described in greater detail below.

First, with frame of reference of <FIG>, as the output member <NUM> and crosswise pin <NUM> moves from left to right in an expanding motion, the linkage <NUM> moves from left to right, causing the first clamping jaw <NUM> to pivot clockwise about the coupling point <NUM> and the pivot point <NUM> until the first clamping jaw <NUM> clamps the first section of pipe <NUM>, at which point the first and second clamping jaws <NUM>, <NUM> pivot clockwise together about the coupling point <NUM>. Thus, the first section of pipe <NUM> is clamped and rotated in a loosening direction with respect to the second section of pipe <NUM>.

Second, with frame of reference of <FIG>, as the output member <NUM> crosswise pin <NUM> moves from right to left in a retracting motion, the linkage <NUM> moves from right to left. As the linkage <NUM> moves left, the first clamping jaw <NUM> pivots clockwise about the pivot point <NUM> until the first clamping jaw <NUM> releases the first section of pipe <NUM>, at which point the first and second clamping jaws <NUM>, <NUM> pivot counterclockwise about the coupling point <NUM>. Thus, the clamping force on the first section of pipe <NUM> is released, such that the first section of pipe <NUM> is not rotated in a tightening direction with respect to the second section of pipe <NUM> during retraction of the crosswise pin <NUM>.

<FIG> illustrates an alternative loosening mechanism <NUM>, which may be used with the pipe fitting tool <NUM> instead of loosening mechanism <NUM>. The loosening mechanism <NUM> includes a linkage <NUM> and a first clamping jaw <NUM> having a jaw portion <NUM>. The first clamping jaw <NUM> is pivotable about a coupling point <NUM> where the first clamping jaw <NUM> is coupled to the linkage <NUM>. The first clamping jaw <NUM> is also pivotably coupled to a second clamping jaw <NUM> at a pivot point <NUM>. In response to reciprocation of the output member <NUM>, the loosening mechanism <NUM> repeatedly undergoes two separate motions, as described below.

First, in the frame of reference of <FIG>, as the output member <NUM> and crosswise pin <NUM> move from left to right in an expanding motion, the linkage <NUM> moves from left to right, causing the first clamping jaw <NUM> to pivot clockwise about the coupling point <NUM> and the pivot point <NUM> until the jaw portion <NUM> clamps the first section of pipe <NUM>, at which point the first and second clamping jaws <NUM>, <NUM> pivot clockwise together about the coupling point <NUM>. Thus, the first section of pipe <NUM> is clamped rotated in a loosening direction with respect to the second section of pipe <NUM>.

Second, with frame of reference of <FIG>, as the output member <NUM> crosswise pin <NUM> moves from right to left in a retracting motion, the linkage <NUM> moves from right to left. As the linkage <NUM> moves left, the first clamping jaw <NUM> pivots counterclockwise about the pivot point <NUM> until the jaw portion <NUM> releases the first section of pipe <NUM>, at which point the first and second clamping jaws <NUM>, <NUM> pivot counterclockwise about the coupling point <NUM>. Thus, the clamping force on the first section of pipe <NUM> is released, such that the first section of pipe <NUM> is not rotated in a tightening direction with respect to the second section of pipe <NUM> during retraction of the crosswise pin <NUM>.

<FIG> illustrates a pipe threader <NUM> with a gear <NUM> for providing rotation to a loosening member <NUM> shown in <FIG>. The pipe loosening member <NUM> includes a body <NUM> and a plurality of clamping members <NUM>. In operation, the pipe loosening member <NUM> is mounted to the gear <NUM> and axially slipped onto a first section of pipe <NUM>. The pipe threader <NUM> is then activated to rotate the gear <NUM>. Rotation of the gear <NUM> causes the pipe loosening member <NUM> to rotate as well, and causes the clamping members <NUM> to cam inwards and clamp onto the first section of pipe <NUM>, thereby loosening it with respect to a second section of pipe.

<FIG> illustrates a pipe fitting tool <NUM> including a holdback assembly <NUM> configured to clamp and hold a second section of pipe (not shown), and a drive assembly <NUM> configured to loosen a first section of pipe <NUM> with respect to the second section of pipe, as explained in further detail below.

As shown in <FIG>, the illustrated holdback assembly <NUM> includes a housing <NUM>, a handle <NUM>, and first and second jaws <NUM>, <NUM> that open and close in response to rotation of the handle <NUM>. Specifically, as shown in <FIG>, the handle <NUM> is coupled to a driveshaft <NUM> via a coupling member <NUM>. A pinion <NUM> is coupled for rotation with the driveshaft <NUM> and is meshingly engaged with a first rack <NUM> and a second rack <NUM>, such that rotation of the pinion <NUM> causes the first and second racks <NUM>, <NUM> to move in opposite directions with respect to one another (<FIG>). The first jaw <NUM> is coupled to the first rack <NUM> via a first plate <NUM> and the second jaw <NUM> is coupled to the second rack <NUM> via a second plate <NUM>. When the first and second jaws <NUM>, <NUM> are clamped on the second section of pipe, a central axis CA of the second section of pipe is positioned between the first and second jaws <NUM>, <NUM> (<FIG>).

With reference to <FIG>, a ratchet wheel <NUM> is coupled for rotation with the driveshaft <NUM> and a pawl <NUM> is biased to engage the ratchet wheel <NUM>. When the pawl <NUM> is engaged against the ratchet wheel <NUM>, the pawl <NUM> inhibits the ratchet wheel <NUM>, and thus the driveshaft <NUM>, from rotating in a loosening direction. However, while the pawl <NUM> is engaged against the ratchet wheel <NUM>, the pawl <NUM> is configured to allow the ratchet wheel <NUM>, and thus the driveshaft <NUM>, to rotate in a tightening direction. The pawl <NUM> is coupled for pivotal movement with a release handle <NUM>, thus allowing the pawl <NUM> to pivot with the release handle <NUM> between an engaged position, in which the pawl <NUM> is engaged against the ratchet wheel <NUM>, and a disengaged position, in which the pawl <NUM> is disengaged from the ratchet wheel <NUM>.

The illustrated holdback assembly <NUM> also includes an adjustment collar <NUM> for adjusting a position of the drive assembly <NUM> with respect to the holdback assembly <NUM>, to thereby ensure that an effective pivot axis EPA of a jaw assembly <NUM> of the drive assembly <NUM> is coaxial with the central axis CA of the second section of pipe, while the first and second jaws <NUM>, <NUM> are clamped on the second section of pipe and the jaw assembly <NUM> is positioned on the first section of pipe <NUM>. Referring to <FIG>, the adjustment collar <NUM> includes a plurality of radial recesses <NUM> corresponding to a plurality of parallel positions of the drive assembly <NUM> with respect to the holdback assembly <NUM>, as explained in further detail below. Each radial recess <NUM> may also correspond to a predetermined diameter of pipe that is to be loosened by the jaw assembly <NUM> of the drive assembly <NUM>. Thus, each radial recess <NUM> is axially and rotationally offset from each other radial recess <NUM> along the adjustment collar <NUM>.

A plurality of detents <NUM>, which may be configured as projections, recesses, or both, is arranged at an end <NUM> of the adjustment collar <NUM>. Each detent <NUM> corresponds to one of the radial recesses <NUM> and is configured to receive a finger <NUM> of a sliding release actuator <NUM>, which is biased toward the adjustment collar <NUM>. In the illustrated embodiment, there are four corresponding pairs of radial recesses <NUM> and detents <NUM>, respectively corresponding to four standard pipe diameters: (<NUM>) <NUM> inch; (<NUM>) <NUM>¼ inches; (<NUM>) <NUM>½ inches; and (<NUM>) <NUM> inches. Thus, the pipe fitting tool <NUM> may be conveniently and quickly set up to interface with four different standard sizes of pipes. However, in other embodiments, there could be more or fewer corresponding pairs of radial recesses <NUM> and detents <NUM>, to provide more or fewer different preset sizes. In the illustrated embodiment, the adjustment collar <NUM> includes a plurality of indicia <NUM> adjacent each detent <NUM> to make apparent which pipe diameter has been selected by the adjustment collar <NUM>.

Each radial recess <NUM> has a rectangular cross-sectional area, such that each radial recess is configured to receive a first end <NUM> of a crossbar <NUM> that extends through the drive assembly <NUM>, as shown in <FIG>. The crossbar <NUM> may be biased toward the adjustment collar <NUM>. A bracket <NUM> coupled to a housing <NUM> of the drive assembly <NUM> includes a sliding potion <NUM> configured to be received in a track <NUM> (<FIG>) on the housing <NUM> of the holdback assembly <NUM>. In the illustrated embodiment, each detent <NUM> and its adjacent indicia <NUM> correspond to the radial recess <NUM> that is rotationally offset by <NUM> degrees, such that when the finger <NUM> is in a particular detent <NUM>, its corresponding radial recess <NUM> is arranged in the track <NUM>. As shown in <FIG>, the crossbar <NUM> extends through the housing <NUM> and the bracket <NUM>. By arranging the sliding portion <NUM> in the track <NUM>, the drive assembly <NUM> is inhibited from moving in a direction parallel to the crossbar <NUM> with respect to the holdback assembly <NUM>, but may slide in a direction perpendicular to the crossbar <NUM> with respect to the holdback assembly <NUM> as long as the first end <NUM> of the crossbar <NUM> is not received in one of the radial recesses <NUM>.

As shown in <FIG>, a pin <NUM> extends through the crossbar <NUM> proximate the second end <NUM> of the crossbar <NUM>. The illustrated pipe fitting tool <NUM> includes a linkage <NUM>, which may be moved away from the jaw assembly <NUM> of the drive assembly <NUM> along the housing <NUM>. The linkage <NUM> has ramps <NUM> to engage the pin <NUM> and move it away from the side of the housing <NUM>. As the pin <NUM> is moved away from the housing <NUM>, the crossbar <NUM> is moved away from the adjustment collar <NUM>, and the first end <NUM> of the crossbar <NUM> is moved out of one of the radial recesses <NUM>. After the first end <NUM> has been removed from one of the radial recesses <NUM>, the drive assembly <NUM> may be adjusted in a parallel manner with respect to the holdback assembly <NUM> by sliding the sliding portion <NUM> (<FIG>) along the track <NUM> (<FIG>).

The release actuator <NUM> may then by moved and held away from the adjustment collar <NUM> to remove the finger <NUM> from one of the detents <NUM>, at which point the adjustment collar <NUM> can be rotated to a new rotational position corresponding to a new pipe diameter, thus aligning a new radial recess <NUM> with the track <NUM>. The release actuator <NUM> may then be released and be biased back into a different detent <NUM> corresponding to the new radial recess <NUM> that is aligned with the track <NUM>, and thereby inhibiting the adjustment collar <NUM> from rotation. The linkage <NUM> may then be released, allowing the crossbar <NUM> to be biased back toward the adjustment collar <NUM> until the first end <NUM> enters the new radial recess <NUM>. The drive assembly <NUM> is thereby set in a new parallel position, corresponding to a new pipe diameter, with respect to the holdback assembly <NUM>.

With reference to <FIG>, the illustrated drive assembly <NUM> includes an electric motor <NUM>, a lead screw <NUM>, and gear train <NUM> to transfer torque from the motor <NUM> to the lead screw <NUM>. The electric motor <NUM> is preferably powered by a battery removably coupled to the housing <NUM>, such as the battery <NUM> described above with reference to <FIG>. In the illustrated embodiment, an output shaft <NUM> of the motor extends parallel to the lead screw <NUM>.

Specifically, a first end <NUM> of the lead screw <NUM> is arranged in and coupled for rotation with a drive member <NUM>. The drive member <NUM> is configured to rotate with a torque transfer member <NUM> coupled for rotation with a gear <NUM> of the gear train <NUM>, via a Double-D cross-sectional geometry, but is configured to move axially with respect to the torque transfer member <NUM>. A thrust bearing <NUM> is arranged around the torque transfer member <NUM> and is set in an upper portion <NUM> of the housing <NUM>. Because the drive member <NUM> is configured to move axially with respect to the torque transfer member <NUM>, the axial thrust force received by the gear <NUM> is reduced, thus preventing the gear <NUM> from binding. A second end <NUM> of the lead screw <NUM> is arranged in a thrust bearing <NUM> in a lower portion <NUM> of the housing <NUM>. In some embodiments, the thrust bearing <NUM> is configured to absorb up to <NUM>,<NUM> lb of thrust load exerted by the lead screw <NUM> on the thrust bearing <NUM> during a pipe loosening operation.

With continued reference to <FIG>, a nut <NUM> is threadably arranged for movement along the lead screw <NUM>. The nut <NUM> is captured within a first end <NUM> of a carriage <NUM> that also has a second end <NUM> arranged around and configured to move along a post <NUM> in the housing <NUM>, via a sleeve <NUM> (e.g., a low-friction sleeve, linear bearing, or the like). Because the carriage <NUM> is arranged on the lead screw <NUM> (via the nut <NUM>) and the post <NUM> (via the sleeve <NUM>), the carriage <NUM> is inhibited from rotating within the housing <NUM>, and is only capable of moving between the upper and lower portions <NUM>, <NUM> of the housing <NUM>. Because the nut <NUM> is captured within the carriage <NUM>, the nut <NUM> is inhibited from rotating about the lead screw <NUM>. Thus, in response to rotation of the lead screw <NUM>, the nut <NUM> will move along the lead screw <NUM> between the upper and lower portions <NUM>, <NUM> of the housing <NUM>, causing the carriage <NUM> to move therewith.

As shown in <FIG>, the carriage <NUM> has two hubs <NUM> on which a pair of sleds <NUM> are respectively arranged. The hubs <NUM> define a hub axis <NUM>, which extends centrally through the hubs <NUM>, and each of the sleds <NUM> has a recess <NUM> (<FIG>) to accommodate a respective one of the hubs <NUM>. Each of the sleds <NUM> is respectively arranged in a slot <NUM> of one of a pair of lever supports <NUM>, such that the sleds <NUM> may move along the slots <NUM> during a pipe loosening operation, as discussed in further detail below. The jaw assembly <NUM> of the drive assembly <NUM> includes the lever supports <NUM>, a lever arm <NUM> coupled between the lever supports <NUM>, a first jaw <NUM> coupled to the lever arm <NUM>, and a second jaw <NUM> pivotally coupled to each of the lever supports <NUM> along a common pivot axis <NUM> (<FIG>).

As shown in <FIG> and <FIG>, a spring <NUM> is seated against a spring slider <NUM> and arranged within a bore <NUM> of the lever arm <NUM>. The spring slider <NUM> thus is biased by the spring <NUM> against the carriage <NUM>. The lever arm <NUM> and both lever supports <NUM> are thus biased by the spring <NUM> away from the spring slider <NUM> and toward the first section of pipe <NUM>, such that in a neutral position the sleds <NUM> are arranged in the slots <NUM> toward ends <NUM> of the lever supports <NUM> (<FIG>).

A pair of pins <NUM> extend from the spring slider <NUM> and into the lever arm <NUM> to inhibit the spring slider <NUM> from rotating with respect to the lever arm <NUM> (<FIG>). As shown in <FIG>, the first jaw <NUM> is removably coupled to the lever arm <NUM> via, for example, a fastener <NUM>, such that different types of jaw pieces or replacement jaw pieces may replace the first jaw <NUM> on the lever arm <NUM>.

The second jaw <NUM> is biased toward the first jaw <NUM> via a pair of tension springs <NUM> coupled between the first and second jaws <NUM>, <NUM>. As shown in <FIG>, a side portion <NUM> extends between the upper and lower portions <NUM>, <NUM> of the housing <NUM> on opposite sides of the carriage <NUM>. A pair of steel bolts <NUM> respectively extend through each of the side portions <NUM>, coupling the upper and lower portions <NUM>, <NUM> of the housing <NUM>.

As shown in <FIG>, a storage hook <NUM> on a slide member <NUM> is configured to hook onto a ledge <NUM> of one of the lever supports <NUM>, thus hooking the jaw assembly <NUM> in a fixed storage position with respect to the housing <NUM>, when the slide member <NUM> is locked in a first position via a detent <NUM> being biased into a first recess <NUM>. The detent <NUM> can be depressed and the slide member <NUM> is slidable along the housing <NUM> to an unlocked position, in which the detent <NUM> is biased into a second recess <NUM>, and the storage hook <NUM> releases the ledge <NUM>, allowing the jaw assembly <NUM> to swing back to an operating position. By putting the jaw assembly <NUM> in a storage position during transport of the pipe fitting tool <NUM>, damage to the jaw assembly <NUM> during transport can be prevented, as opposed to allowing the jaw assembly <NUM> to swing freely with respect to the housing <NUM>.

In operation, after the drive assembly <NUM> has been set in the correct parallel position with respect to the holdback assembly <NUM> for a size of a particular pipe to be loosened, as described above, the first and second jaws <NUM>, <NUM> of the jaw assembly <NUM> are positioned on the first section of pipe <NUM> while the first and second jaws <NUM>, <NUM> of the holdback assembly <NUM> are positioned on opposite sides of the second section pipe. The handle <NUM> of the holdback assembly <NUM> is then rotated in a tightening direction, thus rotating the driveshaft <NUM> in a tightening rotation. In response to the driveshaft <NUM> rotating in a tightening direction, the pinion <NUM> rotates to move the first and second racks <NUM>, <NUM> in opposite directions, such that the first and second jaws <NUM>, <NUM> move toward each other to clamp down on the second section of pipe. Once the first and second jaws <NUM>, <NUM> are clamped on the second section of pipe, the engagement of the pawl <NUM> against the ratchet wheel <NUM> inhibits the jaws <NUM>, <NUM> from moving away from their clamped position.

The motor <NUM> of the drive assembly <NUM> is then activated in a loosening direction, causing the lead screw <NUM> to rotate in a loosening direction. Rotation of the lead screw <NUM> in the loosening direction causes the carriage <NUM> to move toward the upper portion <NUM> of the housing <NUM>, causing the ends <NUM> of the lever supports <NUM> to also move with the carriage <NUM>. As the ends <NUM> of the lever supports <NUM> move with the carriage <NUM> toward the upper portion <NUM>, the first and second jaws <NUM>, <NUM> of the drive assembly <NUM> rotate in a loosening direction about the effective pivot axis EPA (i.e. counterclockwise as viewed in <FIG> and <FIG>), which is coaxial with the central axis CA defined by the second section of pipe, while clamping on the first section of pipe <NUM>, thus loosening the first section of pipe <NUM> with respect to the second section of pipe that is being held by the first and second jaws <NUM>, <NUM> of the holdback assembly <NUM>. As the first and second jaws <NUM>, <NUM> rotate in the loosening direction, the sleds <NUM> simultaneously rotate about the hubs <NUM>.

As the first section of pipe is being loosened, the grip of the first and second jaws <NUM>, <NUM> on the second section of pipe is amplified because the first jaw <NUM> is able to pivot slightly, in a manner similar to a pipe wrench, via a gap <NUM> (<FIG>) at an inner end <NUM> of the first jaw <NUM>. While the lead screw <NUM> is rotating in the loosening direction, the force exerted on the housing <NUM> by the lead screw <NUM> is transferred through the steel bolts <NUM>, in tension, between the upper and lower portions <NUM>, <NUM> of the housing <NUM>. In absence of the steel bolts <NUM>, the stress would be exerted on the housing <NUM> itself, which, being formed of aluminum, would be less suited to take the stress.

After the motor <NUM> has rotated a predetermined amount in the loosening direction, the motor <NUM> reverses direction and rotates in an opposite, return direction, causing the lead screw <NUM> to rotate in an opposite, return direction. Rotation of the lead screw <NUM> in the return direction causes the carriage <NUM> to move toward the lower portion <NUM> of the housing <NUM>, causing the ends <NUM> of the lever supports <NUM> to also move with the carriage <NUM>. As the ends <NUM> of the lever supports <NUM> move with the carriage <NUM> toward the lower portion <NUM>, the first and second jaws <NUM>, <NUM> of the drive assembly <NUM> rotate in a return direction (i.e. clockwise as viewed in <FIG> and <FIG>) about the first section of pipe <NUM>. However, while rotating in the return direction, the second jaw <NUM> is permitted to pivot away from the first jaw <NUM>, such that the first and second jaws <NUM>, <NUM> do not clamp on the first section of pipe <NUM> while rotating in the return direction, such that the first section of pipe <NUM> is not "re-tightened" during a return movement. As the first and second jaws <NUM>, <NUM> rotate in the return direction, the sleds <NUM> simultaneously rotate about the hubs <NUM> and move along the slots <NUM>.

After the motor <NUM> has rotated a predetermined amount in the return direction, the motor <NUM> thereafter repeatedly executes "loosening" and "return" rotation cycles until the first section of pipe <NUM> has become loosened with respect to the second section of pipe. When the operator is satisfied, the operator uses the release handle <NUM> to disengage the pawl <NUM> from the ratchet wheel <NUM> and rotates the handle <NUM> in a loosening direction to unclamp the first and second jaws <NUM>, <NUM> of the holdback assembly <NUM> from the second section of pipe.

Claim 1:
A pipe fitting tool configured to loosen a first section of pipe with respect to a second section of pipe, the pipe fitting tool comprising:
a motor (<NUM>);
a reciprocating member (<NUM>) that reciprocates in response to activation of the motor;
a holdback assembly (<NUM>) configured to clamp and hold the second section of pipe;
characterised by further comprising:
a loosening mechanism (<NUM>) configured to
clamp and rotate the first section of pipe with respect to the second section of pipe in response to a first linear motion of the reciprocating member, and
release the first section of pipe in response to a second linear motion of the reciprocating member, the second linear motion being in a direction opposite the first linear motion.