Abstract:
A pipe peeler for removing a uniform layer of material from the outer surface of a polyethylene pipe is provided. The device comprises a body, a blade, a chain coupled near a first face of the body, a means for coupling the other end of the chain to the body near a second face of the body, a means for tightening the chain around a pipe, and a grip for rotating the device around the pipe in order to peel the pipe. The chain may define a helix shape when wrapped around the pipe, creating a spiral track on the pipe that the blade will follow when the device is pushed around the pipe, thereby creating a uniform spiral peel.

Description:
[0001]    This application is a continuation-in-part of application Ser. No. 13/289,670, filed Nov. 4, 2011. 
     
    
     BACKGROUND 
       [0002]    This invention relates to pipe preparing tools, and more particularly to novel devices for peeling the outer surface of a polyethylene pipe, even when the outside of the pipe does not have a perfectly circular circumference or uniform diameter. 
         [0003]    It is often necessary to remove a portion of the exterior surface of a pipe prior to welding or otherwise affixing the pipe to a coupling. In an electrofusion process for joining plastic pipes, such as those constructed of polyethylene, it is an absolute requirement. Removal of a portion of the exterior surface of the pipe eliminates oxidation of and impurities in the exterior surface of the pipe, and helps ensure a trouble-free joint. 
         [0004]    Uniform peeling of polyethylene pipes can be a difficult task because the pipes are often already “in the field” and affixed in place, thereby limiting the use of larger, more precise pipe peeling machines. Under these circumstances, a uniform peel can be difficult to achieve. Many pipe peelers require multiple attachments, often to the inside of the pipe being peeled, which lengthens the time required to peel the pipe. 
         [0005]    It is an object of the present disclosure to provide a pipe peeler that will create a uniform peel on the end of a polyethylene pipe. 
         [0006]    It is an object of the present disclosure to provide a pipe peeler that will peel in a spiral pattern on the outer surface of a polyethylene pipe. 
         [0007]    It is an object of the present disclosure to provide a pipe peeler that does not require itself to be anchored to the inside of a pipe for use. 
         [0008]    It is another object of the present disclosure to provide a pipe peeler that has no delicate or easily breakable exposed parts and requires minimal or no cleaning. 
         [0009]    It is another object of the present disclosure to provide a pipe peeler that is small, compactable, and lightweight. 
         [0010]    It is another object of the present disclosure to provide a single pipe peeler that may be used on a wide range of pipe circumferences. 
         [0011]    It is another object of the present disclosure to provide a pipe peeler that can peel a circular or oval pipe. 
         [0012]    It is another object of the present disclosure to provide a pipe peeler that can easily be used “in the field” on an immovable pipe. 
         [0013]    It is another object of the present disclosure to provide a pipe peeler whereby a user can release his or her grip on the peeler and the peeler will remain in place on the pipe. 
         [0014]    It is another objected of the present disclosure to provide a pipe peeler that can operate on pipes that do not have perfectly circular outer circumferences or uniform diameters. 
         [0015]    Various other features, advantages and characteristics of the present invention will become apparent to one of ordinary skill in the art after a reading of the following specification. 
         [0016]    In the displayed embodiments, the pipe peeler comprises a cuboid body, a retractable blade, a chain, means for coupling the chain near the front and back of the body, a means for pulling one end of the chain towards the body (and thereby tightening the chain around a pipe), and a grip. The two connection points of the coupling the chain to the body are offset so that the chain forms a helix when the chain is tightened around a pipe. 
         [0017]    As used herein, the term “chain” is meant to include other devices which may encircle a pipe, including but not limited to cables, belts, cords, ropes, harnesses, clamps, and so on. 
         [0018]    As used herein, the term “chain segment” may to refer to less than an entire chain or the entire chain as disclosed in the specification and claims. 
         [0019]    The particular embodiments described below are proven to uniformly peel polyethylene pipe. However, these embodiments and obvious modifications thereof may also uniformly peel pipes with material properties similar to polyethylene. This disclosure and the claims herein are directed toward peelers for pipe with material properties similar to polyethylene. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]      FIG. 1  is a side perspective view of some parts of an embodiment of the invention, with some parts omitted in order to provide a clear view of the parts shown therein; 
           [0021]      FIG. 2A  is a side view of the parts of the embodiment of  FIG. 1 ; 
           [0022]      FIG. 2B  is a top view of the parts of the embodiment of  FIG. 1 ; 
           [0023]      FIG. 2C  is a front view of the parts of the embodiment of  FIG. 1 ; 
           [0024]      FIG. 3A  is a side view of the complete embodiment of the invention, in use on a pipe; 
           [0025]      FIG. 3B  is a side perspective view of the embodiment of  FIG. 3A ; 
           [0026]      FIG. 3C  is a side perspective view of the embodiment of  FIG. 3A ; 
           [0027]      FIG. 4A  is a top view of the embodiment of  FIG. 3A ; 
           [0028]      FIG. 4B  is a rear view of the embodiment of  FIG. 3A ; 
           [0029]      FIG. 4C  is a front view of the embodiment of  FIG. 3A ; 
           [0030]      FIG. 5  is an exploded view of a portion of the embodiment shown in  FIGS. 3A-3C ; 
           [0031]      FIG. 6A  is an exploded view of a second embodiment of the invention; 
           [0032]      FIG. 6B  is identical to  6 A but identifies additional elements of the second embodiment; 
           [0033]      FIG. 7  is a side cross-section view of the second embodiment of  FIGS. 6A and 6B ; 
           [0034]      FIG. 8  is a top view of the second embodiment of  FIGS. 6A and 6B , in use on a pipe. 
           [0035]      FIG. 9  is a rear view of the second embodiment of  FIGS. 6A and 6B , in use on a pipe. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0036]    An embodiment of the pipe peeler surrounding a pipe is shown in  FIGS. 3A ,  3 B, and  3 C generally at  10 . In all embodiments disclosed, substantially all parts of the pipe peeler may be made of metal but are interchangeable with other materials obvious to those skilled in the art. 
         [0037]    Referring to  FIG. 1 , the pipe peeler  10  includes a peeler body  20 . In this embodiment, peeler body  20  is generally cuboid-shaped but other embodiments may take other shapes without adverse effect on the device&#39;s functionality. 
         [0038]    Four wheels  28  are attached to the peeler body  20 . The wheels  28  can be bolted or otherwise affixed to the body  20  and each wheel  28  may rotate about a shoulder bolt. 
         [0039]    Grip shaft  24  is affixed to peeler top face  18 , wherein the affixing may be done by a male thread (not shown) on the grip shaft  24  and female thread (not shown) in the peeler body  20 , or other affixing means such as welding or manufacturing the peeler body  20  and grip shaft  24  in one piece. Likewise, grip knob  22  is affixed to grip shaft  24 , using, for example a male thread (not shown) on the grip shaft and a female thread (not shown) in the grip knob, or other means such as welding or manufacturing the knob  22  and shaft  24  as one piece. 
         [0040]    As shown in  FIG. 2B , peeler front face  12  includes a holding pin recess  58 . Holding pin  48  is affixed inside holding pin recess  58  and is parallel to peeler front face  12 . As seen in  FIG. 1 , one end of holding pin  48  is inside holding pin aperture  72 , while the other end of holding pin  48  may be affixed to the holding pin recess  58  wall opposite holding pin aperture  72  using, for example, a male thread (not shown) on the holding pin end and a receiving female thread (not shown) on holding pin recess  58  wall opposite the holding pin aperture  72 , with, for example, a flathead screwdriver receptor or hex key receptor at the end of the holding pin  48  that is exposed on peeler blade face  16  through holding pin aperture  72 . An alternative to this drawn embodiment is, for example, welding the holding pin  48  in place. The holding pin  48  does not need to be able to rotate when the pipe peeler  10  is in use. 
         [0041]    Peeler back face  14  includes a pivot bar recess  54 . Pivot bar  36  is inside pivot bar recess  54  and is parallel to peeler back face  14 . One end of pivot bar  36  is inside pivot bar aperture  74 , while the other end of pivot bar is inside a recess (not shown) on pivot bar recess  54  wall opposite pivot bar aperture  74 . As shown in  FIG. 2A , one of the wheels  28  holds pivot bar  36  in place. Pivot bar  36  should be able to rotate when the pipe peeler  10  is in use. 
         [0042]    Threaded hook shaft  32  goes through hook pivot aperture  76 . Female threaded cylinder  34  affixes to threaded hook shaft  32 . Threaded hook shaft is connected to, or manufactured as one piece with, hook  26 . Cylinder handle  70  is in female threaded cylinder  34  through cylinder apertures  38 . In this embodiment, cylinder handle  70  is held in place inside female threaded cylinder  34  with spring resistance and friction, but may be held in place using other means such as, for example, welding or manufacturing the female threaded cylinder  34  and cylinder handle  70  as one piece. 
         [0043]    Blade body  50  is affixed to peeler body  20  with two blade body bolts  52  threaded through two female threaded receptors (not shown) on peeler top face  18 . Alternatively, blade body  50  may be affixed to peeler body  20  with welding or other means obvious to those skilled in the art. 
         [0044]    Blade shaft  46  goes through blade body  50  through a cylindrical aperture (not shown) in blade body  46 . Blade shaft  46  is attached to blade knob projection  44 . Blade knob projection is attached to blade knob  40 . The opposite end of blade shaft  46  is attached to blade stop  56 . Blade stop  56  is attached to blade  30 . Alternatively, both blade  30  and blade stop  56  may be attached to blade shaft  46  directly with, for example, a male thread on blade shaft  46  and female threads in blade stop  56  and blade  30 . 
         [0045]    Blade stabilizing pin  62  is affixed to blade shaft  46 . Inside blade body  50  a compressed spring  90  pushes against blade stabilizing pin  62  such that the natural tendency of the spring  90  is to push blade stop  56  and blade  30  away from blade body  50 . The compressed spring  90  may surround blade shaft  46 . 
         [0046]    Blade stabilizing pin  62  may move along the major axis of blade stabilizing elliptical opening  60 , allowing blade  30  to be in a raised or lowered position. However, blade stabilizing pin may not move on the minor axis of blade stabilizing elliptical opening  60 , thereby preventing blade shaft  46  and blade  30  from rotating. 
         [0047]    As shown in  FIG. 2C , when blade knob projection  44  presses against blade body top face  78 , blade  30  does not extend downward beyond wheels  28 . As shown in  FIG. 3B , when blade knob projection  44  is in blade body notch  42 , blade  30  is fully extended and may extend beyond wheels  28  and press against a pipe  68 . Thus, blade  30  may be raised by turning blade knob  40  clockwise and lowered by turning blade knob  40  counterclockwise. 
         [0048]    Before wrapping chain  64  around a pipe  68 , blade  30  is in raised position, i.e., blade knob extension  44  is resting against blade body top face  78 . 
         [0049]    Turning now to  FIGS. 3A ,  3 B, and  3 C, one end of a chain  64  is attached to peeler body  20 . Chain  64  is wrapped around a pipe  68 , and hook  26  threads through chain  64  at a point that enables chain  64  to wrap as tightly as possible around pipe  68 . As seen in  FIG. 3B , at this point pipe peeler  10  may be positioned on pipe  68  such that blade  30  is positioned over the pipe end  80  to be peeled. 
         [0050]    Chain  64  is further tightened by turning cylinder handle  70 , thereby pulling threaded hook shaft  32  and hook  26  into female threaded cylinder  34  and pulling chain  64  toward peeler body  20 . Tightening is continued until pipe peeler  10  is immobile on pipe  68  and will not slide off of pipe even when pipe peeler  10  is not being held by a user. 
         [0051]    If the length of chain  64  is much larger that pipe  68  circumference and the part of chain  64  not being used extends far beyond point at which hook  26  threads through chain, a magnet  66  at end of chain  64  will attach excess loose chain  64  to chain  64  surrounding pipe  68 . 
         [0052]    Once chain  64  is fully tightened around pipe  68 , blade knob  40  may be turned such that blade projection  44  rests in blade body notch  42  thereby allowing blade  30  to extend downward and contact pipe, as seen in  FIG. 3B . 
         [0053]    As shown in  FIG. 4A , chain  64  is slightly offset where the chain end connected to holding pin  48  is closer to pipe end  80  and the chain point connected to hook  26  is slightly farther away from pipe end  80 . 
         [0054]    Once chain  64  is fully tightened and blade  30  is extended to press against pipe  68 , grip knob  22  is pushed in a direction tangential to pipe circumference, toward peeler front face  12 , such that pipe peeler  10  rotates around pipe  68  thereby allowing blade  30  to peel the outer surface of the pipe  68 . 
         [0055]    Due to the slightly giving and springy nature of polyethylene pipe, the pressure of the chain  64  against the pipe  68  will cause the chain  64  to press a temporary “track” into in the pipe  68 . As pipe peeler  10  is rotated around pipe  68 , the chain  64  “track” will direct the pipe peeler  10  to move down the pipe  68  in a uniform spiral, thereby allowing the blade  30  to create a uniform peel. The chain leaves none, or very minimal, permanent “track” on the pipe. 
         [0056]    In this embodiment, the width of the blade  30  is greater than the helical pitch, i.e., greater than the distance that the pipe peeler  10  travels away from the pipe end  80  during one full rotation of the pipe peeler  10  around the pipe  68 . 
         [0057]    Once the pipe  68  has been peeled a satisfactory amount, blade knob  40  may be turned clockwise to raise blade  30 . Cylinder handle  70  is turned to allow hook  26  to move away from female threaded cylinder  34 , thereby allowing chain  64  to loosen and enabling pipe peeler  10  to be removed from pipe  68 . 
         [0058]    A second embodiment of a pipe peeler  110  surrounding a pipe is shown in  FIGS. 8 and 9 . In this embodiment substantially all of the parts may be made of metal but are interchangeable with other materials obvious to those skilled in the art. While this second embodiment functions substantially similarly to the first embodiment discussed above, the second embodiment also includes, among other things, a tensioner  200  with spring  210 , that increases the peeler&#39;s ability to peel non-uniform pipe surfaces, e.g., where the pipe does not have a perfectly circular circumference. 
         [0059]    Referring to  FIG. 6A , the second embodiment pipe peeler  110  includes a peeler body  120  which is generally cuboid-shaped; however, other embodiments may take other shapes without adverse effect on the device&#39;s functionality. 
         [0060]    In this embodiment four wheels  128  are attached to peeler body  120  by attaching wheel bolts  130  to recesses  134  which are threaded (not shown) to receive wheel bolts  130 . Wheels  128  are sandwiched between wheel washers  132  and wheel bolts  130 . The wheels  128  may, for example, include internal ball bearings (not shown) that allow the outer rims of the wheels  128  to rotate while the remainder of each of the wheels  128  are in fixed positions relative to the peeler body  120 . 
         [0061]    Grip  140  is affixed to peeler body  120  by screwing in grip bolts  142  to recesses  144  which are threaded (not shown) to receive grip bolts  142 , thereby securing grip body  150  flush with peeler body  120 . Grip knob  146  includes threaded end  148  that affixes to threaded (not shown) recess  152  in grip body  150 . Of course, a grip body and grip knob may be affixed to the peeler body by other means, for example welding, or manufacturing the peeler and grip as one piece. 
         [0062]    As shown in  FIG. 6A , peeler front face  122  includes a front recess  124 . Hook  160  and side washers  166  are secured to peeler body  120  with holding pin  162  that passes through peeler body aperture  164 , hook  160 , and side washers  166 . Distal beveled pin end  168  lodges into matching-size recess (not shown) opposite aperture  164 . Proximal beveled pin end  172  fits into set screw  170 , which is screwed into threaded (not shown) outer portion of aperture  164 , thereby securing holding pin  162 . Note that hook  160  may pivot on holding pin  162 . Release aperture  174  is a smaller diameter than the holding pin  162  and is used as an access hole to push out the holding pin  162  if needed. 
         [0063]    Peeler back face  180  (see, e.g.,  FIG. 9 ) includes a back recess  182 . Holding pins  184  extend into recess  182  through respective apertures  286  and are held in place in apertures  286  by set screws  188  threaded into threaded (not shown) apertures  190  located on peeler back face  180 . Holding pins  184  fit into pivot block recesses  192 . 
         [0064]      FIG. 7  shows a tensioner  200  cross-section. Tensioner  200  includes an inner shaft  202  with male threads that fit to the female threads of an outer shaft  204 . Outer shaft  204  also includes male threads  206  that fit to the female threads of knob  208 . Disc  212  is between knob  208  and upper end  214  of spring  210 . Lower end  216  of spring may rest against pivot block  218 , and inner shaft  202  goes through pivot block aperture  226 . 
         [0065]    A pin  221  included near first end  222  of chain  220  is affixed to inner shaft  202  through inner shaft aperture  224 . 
         [0066]    Blade body  230  is affixed to peeler body  120  with two blade body bolts  232  screwed into threaded apertures  234  on peeler top face  118  (see  FIG. 8 ). Alternatively, blade body  230  may be affixed to peeler body  120  with welding or other means obvious to those skilled in the art. 
         [0067]    Blade shaft  236  goes through blade body  230  through cylindrical aperture  238 . Blade shaft  236  is affixed to blade stop  240  with barrel nut  242  that screws onto corresponding male threads (not shown) on blade shaft  236 . 
         [0068]    Spring  245  on blade shaft  236  is located between blade stop  240  and cylinder  244 . Cylinder  244  includes aperture  246  through which a stabilizing pin  248  is affixed. Bolt  252  affixes blade  254  and blade stop  256  to cylinder  244 . 
         [0069]    Stabilizing pin  248  may move along the major axis of elliptical opening  250 , allowing blade  254  to be in a raised or lowered position. However, stabilizing pin  248  may not move on the minor axis of elliptical opening  250 , and therefore blade shaft  236  and blade  254  may not rotate. 
         [0070]    Second end  262  of chain  220  is affixed to block  263  and magnet  264  with chain pin  260 . 
         [0071]      FIGS. 8 and 9  display this second embodiment with the chain  220  wrapped around a pipe  295 . A first location  221  (e.g., near first end  222 ) on chain  220  is coupled to peeler body  120  near peeler back face  180  via tensioner  200 . Chain  220  is wrapped snugly around pipe  295 , and second location  290  on chain  220  is coupled to peeler body  120  near peeler front face  122  via hook  160 . 
         [0072]    Knob  208  is turned clockwise, thereby threading outer shaft  204  with inner shaft  202  and initially pulling outer shaft  204  (and thus knob  208  and disc  212 ) toward chain first location  260 . However, turning the knob  208  clockwise eventually presses disc  212  against spring  210 , such that spring  210  is compressed between disc  212  and pivot block  218 , which act as stoppers for spring  210 . Thus, further threading of outer shaft  204  with inner shaft  202  will cause inner shaft  202  to pull upwards toward knob  208  thus tightening chain  220  around pipe  295 . (Of course, tightening chain  220  will also cause additional compression to spring  210 .) Chain  220  should be sufficiently snug around pipe  295  such that the device will not slide off the pipe even when the device is not being held by a user, but for optimal use  220  should not be tightened to the point where spring  210  is completely compressed. 
         [0073]    If the length of chain  220  is much larger that pipe  295  circumference and the part of chain  220  not being used extends far beyond point at which hook  160  couples to chain second location  290 , the magnet  264  will attach excess loose chain to the chain surrounding the pipe. 
         [0074]    Once chain  220  is fully tightened around pipe  295 , blade stop  240  may be turned such that projection  241  rests in blade body notch  243  thereby allowing blade  254  to extend downward and contact pipe. 
         [0075]    Back recess  182  is offset from front recess  124 , resulting in second chain location  290  at hook  160  being offset from first chain location  221 / 222 . As a result, as seen in  FIGS. 8 and 9 , the chain between first chain location  221 / 222  and second chain location  290  forms a helix shape when this portion of the chain is made into an arc, e.g., when it is wrapped around a pipe. (The amount of offset helps determine the helical angle of the chain  220  secured around a pipe  295 .) 
         [0076]    The embodiment shown in  FIGS. 6A-9  is optimal for use where the pipe to be peeled is not perfectly circular, for example, is oval, or is deformed, or changes diameter along its length. Where more “give” is required on chain  220  because a portion of the peeling path is not perfectly circular, spring  210  may compress, thereby allowing chain  220  at first chain location  221 / 222  to move away from peeler back face  180 . Likewise, where the peeling path may ordinarily result in slack on the chain  220 , spring  210  may expand, thus pulling first chain location  221 / 222  toward peeler back face  180 . 
         [0077]    Of course, where the pipe being shaved does not have a uniform circular circumference or constant diameter, the chain likewise may not define a perfect circular helix, even though the tightened chain between first and second locations  260 ,  190  will still be substantially helix-shaped. For example, an elliptical pipe may result in the chain defining an elliptical helix, a cone-shape pipe may result in the chain defining a conic helix, a pipe with a bulge may still result in the chain being substantially helical, and so on. 
         [0078]    Various changes, alternatives, and modifications will become apparent to a person of ordinary skill in the art after a reading of the foregoing specification. It is intended that all such changes, alternatives, and modifications as fall within the scope of the appended claims be considered part of the present invention.