Pipe bender angle indicator

An angle indicator is provided for use with a pipe bender and is adapted to be removably mounted to a handle of a pipe bender. The angle indicator includes a plate; a first wheel rotatably mounted to the plate and including a plurality of angle indicating marks evenly spaced about a periphery of the first wheel; a second wheel rotatably mounted to the plate concentrically with the first wheel; the second wheel being smaller in diameter than the first wheel and including a mark at a periphery of the second wheel, the mark being selectively alignable with one of the angle indicating marks of said first wheel; a bubble level mounted on the second wheel; a first lock to hold the first wheel in a desired rotational position; and a second lock to hold the second wheel in a desired rotational position. The use of two wheels allows for zeroing of the angle indicator and dialing in of the desired angle.

CROSS-REFERENCE TO RELATED APPLICATIONS
 Not Applicable
 STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 Not Applicable.
 BACKGROUND OF THE INVENTION
 This invention relates to pipe benders, and, in particular, to an angle
 indicator for a pipe bender which can be mounted to the handle of a pipe
 bender.
 Pipe benders have long been used by electricians to bend piping through
 which electrical wires pass. Such pipe benders, as is known, include a
 curved bending head or shoe which receives the pipe to be bent, and a
 handle which can be grasped by the electrician. To bend the pipe, the
 electrician simply places the pipe in the head, and pivots the head using
 the handle to bend the pipe. The pipe is bent around the curvature of the
 shoe until the desired angle of bend is reached.
 When an electrician bends a pipe, he tries to achieve a particular angle,
 typically 45.degree. or 90.degree.. However, other size angles are often
 required. If a pipe is not bent to the desired angle (i.e., if the angle
 is overshot or undershot), then the pipe will not lay were desired, and
 the pipe may not lay flush against a surface, for example. This can impact
 wall construction in a building. It is thus desirable to enable
 electrician to determine as accurately as possible when a desired angle is
 reached.
 Many different angle indicators have been developed. Many are incorporated
 into the head or shoe of the pipe bender. This obviously requires that a
 special mold be made for the pipe bender head, and thus increases the cost
 of the pipe bender. Further, when the angle indicator is built into the
 head, if the indicator should break, it cannot be replaced without
 replacing the entire head. For these reasons, pipe bender heads with angle
 indicators have not been well accepted by the industry.
 Other angle indicators have been developed which clip to the handle of the
 pipe bender. These indicators are large, and thus difficult to use, or
 electric, and hence expensive.
 BRIEF SUMMARY OF THE INVENTION
 Briefly stated, an angle indicator of the present invention is intended for
 use with a pipe bender and is adapted to be removably mounted to the
 handle of the pipe bender. The angle indicator includes a mount adapted to
 mount the angle indicator to a handle of the pipe bender. Preferable, the
 mount is in the form of a spring clip, so that the angle indicator can
 simply be pressed onto the handle of the pipe bender and pulled off after
 the pipe has been bent.
 A plate extends from the mount and first and second wheels are rotatably
 mounted to the plate. The second plate is smaller than the first plate and
 is mounted concentrically with the first plate. The first plate includes a
 plurality angle indicating marks evenly spaced about a periphery of the
 first wheel. The second plate includes a mark at a periphery of the second
 wheel. The second wheel mark is selectively alignable with one of the
 angle indicating marks of the first wheel.
 A bubble level is mounted on the second wheel. The bubble level can either
 be a straight or a curved level. If it is a straight level, it is
 preferably extends across the second wheel in a line perpendicular to the
 mark on the second wheel. If the bubble level is curved, it can be mounted
 to the periphery of the second wheel, or along the edge of the second
 wheel.
 A lock is provided to hold the first and second wheels in desired
 rotational positions. The angle indicator includes a bolt having a
 threaded shaft and a head at an end of the shaft. The threaded shaft is
 received in the plate and defines an axle about which the first and second
 wheels rotate. In the disclosed embodiment, the shaft extends through the
 plate, and a nut is received on the shaft on a back side of the plate. The
 bolt defines the lock. By tightening the bolt down, unwanted movement of
 the wheels are prevented and when the bolt is loosened, the wheels can be
 moved relative to each other.
 The angle indicator is preferably also provided with a second lock,
 independent of the first lock, to locks the first wheel in place relative
 to the plate. The second lock includes a threaded shaft with an enlarged
 head on the shaft. The shaft passes through the plate adjacent the first
 wheel such that the head overlaps the first wheel. A nut is received on
 the shaft on the back side of the plate. When the second lock is tightened
 down, the head frictionally engages the first wheel to prevent unwanted
 movement of the first wheel relative to the plate.
 In a second embodiment, the angle indicator includes only one wheel, on
 which a curved bubble level is mounted. The wheel includes a plurality of
 angle indicators at the periphery of the wheel, and the bubble level can
 be mounted on either side of the markings.
 In a third embodiment, the lock for the for one or both of the wheels of
 the first embodiment or for the one wheel in the second embodiment, can
 comprise a ball and detent. In this situation, the axle about which the
 wheels rotate would be provided with a spring biased ball which radiates
 from the axle, and the wheel would be provided with detents (or similar
 structure) with which the ball would interact to hold the wheel in a
 desired position.
 The advantage of either embodiment, is that the angle indicator allows for
 zeroing of the indicator. Hence, the indicator can be used with almost
 every pipe bender, no matter the angle between the pipe bender handle and
 the ground prior to bending of the pipe.

Corresponding reference numerals will be used throughout the several
 figures of the drawings.
 DETAILED DESCRIPTION OF THE INVENTION
 The following detailed description illustrates the invention by way of
 example and not by way of limitation. This description will clearly enable
 one skilled in the art to make and use the invention, and describes
 several embodiments, adaptations, variations, alternatives and uses of the
 invention, including what I presently believe is the best mode of carrying
 out the invention.
 A typical pipe bender 1 is shown in FIG. 3. The pipe bender 1 includes a
 head 3 having a curved shoe 5 and a stem 7 extending up from the shoe 5. A
 handle 9 is removably received in the stem 7 and can be grasped by an
 electrician to pivot the head 3 to bend a pipe as is known. The head 3
 does not form any part of the present invention, and can be a conventional
 head. Not all pipe benders are made the same. Thus, the stem 7, and hence
 the handle 9, may not always extend from the shoe 5 at the same angle.
 Stated differently, the handle 9 of different pipe benders can form
 different angles with the ground when the pipe is received in the shoe,
 but before the pipe is bent.
 An angle indicator 11 of the present invention is shown mounted to the
 handle 9. The angle indicator 11 is shown in more detail in FIGS. 2-4. The
 angle indicator includes a backing plate 13 extending from a mounting clip
 15. The clip 15 is shown to be a spring clip which spreads apart as it is
 pressed onto the handle 9, and then springs back to a normal position to
 grip the handle 9 to hold the indicator 11 in place on the handle 9. The
 clip 15 defines an arc which is slightly more than 180.degree., so that it
 can be pressed onto and grasp the handle 9 and so that it can be easily
 removed from the handle simply by pulling. Any other conventional type of
 mounting bracket could be used to removably secure the indicator 11 to the
 handle. For example, the mounting bracket could include a pair of spaced
 apart legs which are tightened together using a screw. Or, straps with
 Velcro could be used to mount the plate 13, and hence the indicator 11, to
 the handle 9. Alternatively, the clip 15 could include magnets to
 magnetically mount the indicator 11 to the handle 9.
 The backing plate 13 includes a pair of holes, 17 and 19. A first wheel 21
 and a second wheel 23 are rotatably mounted to the backing plate 13. The
 two wheels are mounted to the backing plate 13 with the first wheel
 adjacent the plate 13, and the second wheel 23 on top of the first wheel
 21. As shown, the first and second wheels 21 and 23 each have a central
 hole 25 and 27, respectively, and a screw 29 passes through the central
 holes of the two wheels and through the hole 17 in the plate 13. A nut 31
 on the back side of the plate 13 is used to tighten the screw 29 in place.
 As can be appreciated, the screw 29 defines an axle about which both
 wheels 21 and 23 rotate. Although a screw is provided, the second wheel 23
 can be formed to include a threaded shaft extending from the back surface
 of the wheel to pass through the first wheel 21 and the plate 13 to
 receive the nut 31.
 Although the screw is shown held in place by the nut 31, the hole 17 into
 which the screw 29 passes could be threaded, and the screw could be
 screwed into the plate 13. This would eliminate the need for the nut 31.
 The first wheel 21 includes a plurality of angle markings 33 extending
 around the periphery of the wheel. The first angle marking is indicated to
 be at 0.degree.. The angle markings 33 are shown to extend a full 1800
 around the wheel 21 with larger markings showing increments of 15.degree.
 and smaller markings showing increments of 5.degree..
 The second wheel 23 is smaller in diameter than the first wheel 21 and
 includes a single indicating line 37. The second wheel 23 is sized so that
 the angle markings of the first wheel 21 are visible when the angle
 indicator 11 is assembled, as seen in FIGS. 1 and 2. A bubble or spirit
 level 39 is mounted to the second wheel 23. As shown, the level 39 extends
 across the diameter of the second wheel 23. Also, the level 39 is shown
 mounted to a spacer 41, which in turn, is mounted to the second wheel. The
 spacer 41 allows for clearance for the head of the screw 29. As can be
 seen, the bubble level is shown to be a straight level, and extends
 generally perpendicularly to the line 37.
 A second lock screw 43 is received in the second hole 19 in the plate 13.
 The hole 19 is positioned, as seen in FIG. 2, so that the head 45 of the
 screw 43 overlaps the edge of the first wheel 21. The hole 19 can be a
 threaded hole which receives the screw 43. Alternatively, a nut can be
 received on the shaft of the screw 43 on the back side of the plate 13.
 The first wheel 21 is directly against the plate 13 and the second wheel 23
 is directly against the first wheel 21. As can be appreciated, when the
 nut 31 is tightened against the back surface of the plate 13, the two
 wheels are fixed in position, and can not be readily moved relative to
 each other. When the nut 31 is loosened, the two wheels can move relative
 to each other. The bolt 29 and nut 31 thus act as a lock to lock the
 wheels in position, as will be described below.
 In operation, the angle indicator 11 is clipped to the handle 9 of the pipe
 bender 1. As noted above, with the spring clip 15, this is accomplished
 simply by pressing the mounting clip over the handle 9. The nut 31 which
 is threaded onto the shaft 29 and the lock screw 43 are loosened so that
 both the first wheel 21 and the second wheel 23 can rotate about the screw
 29. The two wheels are not connected to each other and hence can rotate
 relative to each other.
 After the pipe bender has been applied to the pipe, the first step is to
 zero the angle indicator. This is accomplished by rotating the second
 wheel until the bubble B in the level 39 is centered to indicate that the
 level 39 is horizontal or parallel to the ground. The first wheel is then
 rotated until its zero mark lines up with the line 37 on the second wheel
 23. The zeroing operation can also be done by first lining up the zero
 mark on the first wheel with the line 37 on the second wheel 23 and then
 rotating the two wheels together until the bubble level indicates that the
 level is horizontal. The lock screw 43 is then tightened to lock the first
 wheel 21 in position.
 The second wheel 23 is then rotated to line up its mark 37 with a desired
 degree mark 33 on the first wheel. Thus, for example, if a 25.degree.
 angle is desired, the second wheel is rotated until the mark 37 lines up
 with the first wheel mark 33 corresponding to 25.degree.. The nut 31 is
 rotated to tightened the screw 29 down to lock the second wheel 23 in
 position.
 The lock screw 43 provide a separate lock for the first wheel so that the
 first wheel can be locked in position, and the second wheel can be rotated
 without fear of rotating the first wheel. However, because the second lock
 (i.e., the screw 29 and nut 31) holds both the first and second wheels in
 their desired positions, the lock screw 43 could be eliminated if desired.
 Once the angle has been indicated, the electrician bends the pipe in the
 usual manner, keeping an eye on the level. When the level bubble is
 centered, to indicate that the level is horizontal, the desired bend for
 the pipe is reached, and the electrician can stop the bending process.
 Although the angle indicator 11 is shown with a straight bubble level 39, a
 curved bubble level could be provided as well. The operation of the angle
 indicator would be the same.
 A second embodiment of the angle indicator is shown in FIG. 5. The angle
 indicator 11' includes a mounting clip 15' and plate 13' which are
 identical to the clip 15 and plate 13 of the indicator 11. However, rather
 than having two wheels, the angle indicator 11' includes only one wheel
 21'. A plurality of angle indicating marks 33' are formed about the
 periphery of the wheel 21'. The marks 33' are shown to extend about 180"
 around the wheel, but could extend further if desired. A curved bubble
 level 39' is mounted to the wheel 21' inside of the marks 33'.
 Alternatively, the bubble level 39' could be mounted to the edge of the
 wheel 21'. The indicator 11' also includes a lock 43' identical to the
 lock 43 of the indicator 11.
 In use, after the indicator 11' is clipped to the handle, the lock 43' is
 loosened and the wheel 21' is rotated until the bubble B is centered in
 the level 39', as shown in FIG. 5. This zeros the indicator and the wheel
 21' can then be locked in place by tightening the screw 43'. The pipe is
 bent until the bubble lines up with the angle marking 33' corresponding to
 the angle of the desired bend. In the indicator 11', because the angle
 markings 33' are on the wheel 21', the mark 33a in the center of the
 markings will always correspond to 0.degree.. As with the indicator 11,
 the markings 33' are spaced apart by 5.degree., with larger marks every
 15.degree..
 In the indicator 11', the angle markings 33' are on the wheel 21'.
 Alternatively, the markings 33' could be on the backing 13' adjacent the
 wheel. In this instance, the pipe bender must note which marking 33' the
 bubble B lined up with when the indicator 11' was zeroed. From that point,
 knowing that the markings 33' are separated by 5.degree., for example, the
 pipe bender can determine which marking the bubble B needs to line up with
 to arrive at the desired angle.
 The angle indicator is designed to be small so that it can easily fit in a
 shirt pocket, tool belt, tool box, etc. For example, the first and second
 wheels can have diameters of about 2" and 11/2 respectively. With wheels
 this size, the plate would be about 2" across and 2" tall, and the clip
 would be about 2" long. The indicator would have a height, from the bottom
 of the clip to the top of the plate of about 3". The indicator could be
 made smaller is smaller wheels were used.
 The stems 7 of commercially pipe bender heads do not always extend up at
 the same angle. Thus, when a pipe bender is applied to a pipe, the handles
 from different heads will extend at different angles relative to the
 ground. The ability to zero the angle indicator 1 allows the angle
 indicator to be used with many different heads, and the angle of
 attachment of the handle 9 to the head 3 does not matter.
 In another variation, at least the lock for the second wheel 23 of the
 indicator 11" could be replaced with a ball and detent or similar means,
 as seen in FIG. 6. In such an instance, for example, the screw 29 could be
 replaced with a post 29" which would serve as the axle for the wheels 21"
 and 23". The post 29" would include a short bore 51" into which a spring
 53" and a ball 55" are placed, such that the spring biases the ball
 outwardly. The edge of the central opening 25" of wheel 23" would then be
 provided with a series of spaced apart detents 57". The spring biased ball
 55" would interact with the detents 57" of the wheel to hold the wheel in
 the desired position. As can be appreciated, a lock could be provided for
 the wheel 21 or the wheel 21' of indicator 11'. The ball and detent could
 also be replaced with a short, but flexible finger extending from the
 post. The wheel(s) would be provided with grooves on the edge of their
 central openings. The finger would interact with the groove to hold the
 wheel in a desired position. Although the springs 53" and balls 55" are
 shown to be placed in the post 29" with the detent 57" in the wheels, the
 balls and detents could be reversed: the spring and balls could be
 received in the wheels and the detents could be formed about the post 29".
 As can be appreciated, I have disclosed an angle indicator that has the
 advantage of being usable with any pipe bender, by merely zeroing the
 indicator for the particular pipe bender. In fact, once the angle
 indicator has been zeroed for use with a particular pipe bender, it need
 not be zeroed again. However, it would be advisable to periodically check
 the zeroing of the indicator to ensure that the wheel 23 has not moved.
 Additionally, because the indicator has the ability to dial in a desired
 angle, the angle of a pre-bent pipe can be duplicated without the need for
 knowing the angle of the bend in that pipe. The pipe bender, with the
 indicator thereon, is applied to the pre-bent pipe, and the wheel 23 (or
 21' or 23") is rotated until the bubble is level. This will dial in the
 angle of the pre-bent pipe. Then, with the angle dialed in, the bender can
 be used, as described above, to form substantially identical bends in
 straight pipe. This bend can then be duplicated numerous times, without
 the need to reset the indicator.
 As various changes could be made in the above constructions without
 departing from the scope of the invention, it is intended that all matter
 contained in the above description or shown in the accompanying drawings
 shall be interpreted as illustrative and not in a limiting sense. For
 example, the screw 29 can be replaced with a simple axle that is headed
 over on opposite sides to hold the two wheels 21 and 23 to the plate 13
 and to allow the two wheels to rotate relative to each other. The angle
 indicator could be supplied with a second lock screw, similar to the lock
 screw 43, which would include a finger which would press down on the
 second wheel when the screw is tightened to lock the second plate in the
 desired position. Alternatively, the first wheel 21 can be provided with
 an arced slot through which a second bolt could extend. This second bolt
 would be the second lock which locks the second wheel in place.
 Alternatively, spring clips can be provided for one or both of the wheels
 which frictionally engage the wheels to hold them in the desired position.
 All that is required is that the two wheels 21 and 23 (of indicator 11) be
 able to rotate relative to each other, and that there be a locking
 mechanism for the two wheels of the indicator 11 or of the one wheel 21'
 of the indicator 11' so that the wheels can be secured in desired
 positions. These examples are merely illustrative.