Abstract:
A device for cleaning welds. The device comprises a bristles pad, the bristles pad being electrically conductive to deliver electrical current to a weld to be cleaned when the bristles pad is in physical contact with the weld. The device further includes a bristles pad support, the bristles pad support including an elongated body receiving the bristles pad and extending along the bristles pad, the elongated body including a first section and a second section attached to each other, the first section being separable from the second section to reduce a length of the bristles pad support.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit and priority to U.S. provisional application No. 62/033,003, filed on Aug. 4, 2014 and to U.S. provisional application No. 62/182,814, filed on Jun. 22, 2015, the content of which is herein incorporated by reference. 
     
    
     FIELD OF THE TECHNOLOGY 
       [0002]    The present disclosure generally relates to a device and process for cleaning welds. 
       BACKGROUND 
       [0003]    Welding of metals products such as stainless steel products may result in heat tint discoloration in the heat-affected zone of the stainless steel weld. The heat tinting is generally a thickening of the naturally occurring oxide layer on the surface of stainless steel. As heat tint colors are formed on stainless steel, chromium is drawn from below the surface of the metal to form a chromium rich oxide surface layer. This leaves the metal just below the surface with a lower chromium level. The reduction in the sub-surface chromium typically reduces the corrosion resistance of the steel. In order to restore the corrosion resistance of the finished stainless steel product, the weld heat tint needs to be removed. 
         [0004]    It is common procedure to clean the weld to remove the weld heat tint, which typically results in rebuilding of the passive layer around the weld and the restoration of the corrosion resistance of the weld. The removal of heat tint from welds of stainless steel may be done by techniques such as using pickling pastes, wire brushing, grinding or electrolytic methods. The use of pickling pastes can be hazardous while brushing and grinding is a labor-intensive process, leaving electrolytic methods as usually a safer, faster and more cost effective way for cleaning welds. 
         [0005]    Existing welding cleaning systems that make use of electrolyte methods typically use a brush with electrically conductive bristles, such as bristles made of carbon fiber strands, which is supplied with an electric current and an electrolyte solution. When the carbon fiber tipped brush with the electric current and electrolyte solution is applied to the welded area affected by heat tint, an electrochemical cleaning of welded area occurs. Weld cleaning systems of this type are used to clean welds which were formed using gas tungsten arc welding, also known as tungsten inert gas (TIG) welding. 
         [0006]    A popular type of welding is gas metal arc welding, also known as metal inert gas (MIG) welding. However, a problem with existing weld cleaning systems is that for the cleaning systems to clean a MIG weld a higher current is usually required, when compared with the current level required to clean a TIG weld. When a higher current is required, the carbon fiber brush wears down faster requiring the brush to be replaced more frequently. The frequent replacement of the carbon fiber brush can be problematic, as carbon fiber brushes are relatively expensive. 
         [0007]    Therefore, given the relatively high cost of replacing a brush in a weld cleaning system, there is a need in the industry to provide an apparatus and process that alleviates, at least in part, the deficiencies with existing apparatuses and processes for cleaning welds. 
       SUMMARY OF THE INVENTION 
       [0008]    As embodied and broadly described herein, the invention provides in a first aspect a device for cleaning welds. The device comprises a bristles pad, the bristles pad being electrically conductive to deliver electrical current to a weld to be cleaned when the bristles pad is in physical contact with the weld. The device further includes a bristles pad support, the bristles pad support including an elongated body receiving the bristles pad and extending along the bristles pad, the elongated body including a first section and a second section attached to each other, the first section being separable from the second section to reduce a length of the bristles pad support. 
         [0009]    In a specific and non-limiting example of implementation, the bristles pad has a working end portion for engaging the weld, and an opposite support end portion mounted to an end-piece configured to be grasped by a hand of an operator. The bristles pad support is mounted to the bristles pad in a non-sliding relationship such as to permanently preclude the bristles pad support to slide along the bristles pad. 
         [0010]    The first section is linked with the second section through a frangible connection that can be manually snapped-off to separate the first section from the second section. Alternatively, the first section is linked with the second section through a connection allowing separation of the first and second section and a subsequent re-connection of the first and second sections. 
         [0011]    Optionally, the device includes a fluid connection between the end-piece and the bristles pad to supply weld-cleaning fluid to the bristles pad and also includes an electrical connection between the end-piece and the bristles pad to supply electrical power to the bristles pad. 
         [0012]    As embodied and broadly described herein, the invention provides in a second aspect a device for cleaning welds. The device comprising a bristles pad, the bristles pad being electrically conductive to deliver electrical current to a weld to be cleaned when the bristles pad is in physical contact with the weld and a bristles pad support, the bristles pad support including an elongated body receiving the bristles pad and extending along the bristles pad, the elongated body having an adjustable length allowing to vary a length of a portion of the bristles pad engaged by the bristles pad support. 
         [0013]    In a non-limiting example of implementation the device for cleaning welds as defined in claim  15 , wherein the bristles pad is mounted to an end-piece configured to be grasped by the hand of an operator. A fluid connection is provided between the end-piece and the bristles pad to supply weld-cleaning fluid to the bristles pad along with an electrical connection to supply electrical power to the bristles pad. 
         [0014]    The bristles pad support includes a plurality of sections arranged into a stack and defining a void area for receiving the bristles pad. The plurality of sections are separable from each other. They can be connected to each other by frangible connections such that they can be manually snapped-off. Alternatively, the connections can be such as to allow the sections to be separated and subsequently re-assembled. 
         [0015]    As embodied and broadly described herein, the invention provides in a third aspect a device for cleaning welds, comprising a bristles pad, the bristles pad being electrically conductive to deliver electrical current to a weld to be cleaned when the bristles pad is in physical contact with the weld and a bristles pad support, the bristles pad support including an elongated body receiving the bristles pad and extending along the bristles pad, the elongated body being adjustable to acquire a curved shape such as to force the bristles pad to bend. 
         [0016]    As embodied and broadly described herein, the invention provides in a fourth aspect a bristles pad, the bristles pad being electrically conductive to deliver electrical current to a weld to be cleaned when the bristles pad is in physical contact with the weld and a bristles pad support, the bristles pad support including an elongated body receiving the bristles pad and extending along the bristles pad, the elongated body including a pair of telescoping sections. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    A detailed description of embodiments of the invention is provided below, by way of example only, with reference to the accompanying drawings, in which: 
           [0018]      FIG. 1  shows an example of a weld cleaning system in which embodiments of the invention may be implemented in accordance with a specific example of implementation of the invention. 
           [0019]      FIG. 2A  is a perspective view of an assembly of an end-piece in accordance with an embodiment of the invention. 
           [0020]      FIG. 2B  is an exploded view of an assembly of the end-piece illustrated in  FIG. 2A . 
           [0021]      FIG. 3A  is a perspective view of a brush in accordance with an embodiment of the invention. 
           [0022]      FIG. 3B  is a perspective view of the brush illustrated in  FIG. 3A  where the bristles pad is shown in a see-through layout for clarity. 
           [0023]      FIG. 4A  is a perspective view of a brush support in accordance with an embodiment of the invention. 
           [0024]      FIG. 4B  is a perspective view of the brush support and a connection tip in accordance with an embodiment of the invention. 
           [0025]      FIGS. 5A, 5B, 5C and 5D  are perspective views of the brush, illustrating the process for inserting the brush into the brush support in accordance with an embodiment of the invention. 
           [0026]      FIG. 6A  is a perspective view of an assembly of an end-piece of a dual brush arrangement in accordance with an embodiment of the invention. 
           [0027]      FIG. 6B  is a perspective view of a brush support for a dual brush arrangement in accordance with an embodiment of the invention. 
           [0028]      FIG. 7A  is a perspective view of an assembly of an end-piece of a triple brush arrangement in accordance with an embodiment of the invention. 
           [0029]      FIG. 7B  is a perspective view of a brush support for use with the triple brush arrangement in accordance with an embodiment of the invention. 
           [0030]      FIG. 8A  is a perspective view of an assembly of a triple brush end-piece where the brushes are arranged in a triangular configuration in accordance with an embodiment of the invention. 
           [0031]      FIG. 8B  is a perspective view of a brush support for use with the triple brush arrangement of  FIG. 8A . 
           [0032]      FIG. 9  is a perspective view of a plug in accordance with an embodiment of the invention. 
           [0033]      FIG. 10  is a perspective view of an adjustable brush. 
           [0034]      FIG. 11A  is a perspective view of the brush and a bristles pad positioning attachment in accordance with an embodiment of the invention. 
           [0035]      FIG. 11B  illustrates the bristles pad positioning attachment where the first piece and the second piece are not attached to each other. 
           [0036]      FIG. 11C  is a perspective view of the brush and the bristles pad positioning attachment in a different position in accordance with an embodiment of the invention. 
           [0037]      FIG. 12  is a perspective view of the brush and a bristles pad positioning attachment for positioning the bristles generally circularly in accordance with an embodiment of the invention. 
           [0038]      FIG. 13A  is a perspective view of the brush and a bristles pad positioning attachment for spreading the bristles in accordance with an embodiment of the invention. 
           [0039]      FIG. 13B  illustrates the bristles pad positioning attachment where the first piece and the second piece are not attached to each other. 
           [0040]      FIG. 13C  is a perspective view of the brush and a bristles pad positioning attachment for spreading the bristles in a different position in accordance with an embodiment of the invention; 
           [0041]      FIGS. 14A and 14B  are top views of hand pieces with bristles pad supports made of stacks of twist rings; 
           [0042]      FIGS. 15A and 15B  are perspective views of twist rings of the type used for the stack shown in  FIG. 14A ; 
           [0043]      FIG. 15C  is a perspective view of a twist ring according to a variant that has knurls for a better grip; 
           [0044]      FIG. 16A  is a perspective view of a twist ring of the type used for the stack shown in  FIG. 14B ; 
           [0045]      FIG. 16B  is a perspective view of a twist ring according to a variant that has knurls for a better grip; 
           [0046]      FIGS. 17A and 17B  are top views of hand pieces using bristles pad support rings made of stacks of friction rings; 
           [0047]      FIGS. 18A and 18B  are perspective views of friction rings of the stack shown in  FIG. 17A ; 
           [0048]      FIG. 18C  is a perspective view of a friction ring according to a variant that has knurls for a better grip; 
           [0049]      FIG. 19A  is a perspective view of a friction ring of the type used for the stack shown in  FIG. 17B ; 
           [0050]      FIG. 19B  is a perspective view of a friction ring according to a variant having knurls for a better grip; 
           [0051]      FIG. 20  is a perspective view of a support ring using magnetic retention force; 
           [0052]      FIG. 21  is a perspective view of a hand piece using a bristles support pad having frangible support elements; 
           [0053]      FIGS. 22A-22E  are perspective views of bristles pad supports with spouts designed to provide to the bristles pad a desired cross sectional shape; 
           [0054]      FIG. 23  is a cross-sectional view of a multi-element bristles pad support, the elements being connected by ball joints; 
           [0055]      FIG. 24  is a view similar to  FIG. 23  in which the bristles pad support is being flexed to angularly orient the bristles pad; 
           [0056]      FIG. 25  is a perspective exploded view of a bristles pad and a bristles pad support that is slidable along the bristles pad. 
       
    
    
       [0057]    It is to be expressly understood that the description and drawings are only for the purpose of illustrating certain embodiments of the invention and are an aid for understanding. They are not intended to be a definition of the limits of the invention. 
       DETAILED DESCRIPTION 
     Weld Cleaning System 
       [0058]      FIG. 1  shows a weld cleaning system  100  in which embodiments of the invention may be implemented. In general, the weld cleaning system  100  is used to remove/clean heat tint in the heat-affected zone of welded stainless steel products. In this embodiment, the weld cleaning system  100  includes a weld-cleaning machine  105 , a control panel  110 , a feed line  130 , a ground connector  120 , an end-piece  200  and a solutions reservoir (not illustrated). 
         [0059]    The weld-cleaning machine  105  typically houses the operational components of the weld cleaning system  100 . The weld-cleaning machine  105  is connected to a power supply by a power cord (e.g., an electrical outlet) and the operational components are controlled via the control panel  110  to supply the desired electrical output and optionally the solution from the solutions reservoir to the feed line  130 . 
         [0060]    The control panel  110  typically may include features such as a main power switch, amperage regulating switch, solution pump switch, end-piece selector switch and/or any other suitable feature. 
         [0061]    The feed line  130  typically is used to provide electricity and optionally solution to the end-piece  200  from the weld-cleaning machine  105 . Usually the intensity of the electrical current and the type of current, such as direct current (DC) or alternating current (AC) can be set as desired by the operator on the control panel  110 . 
         [0062]    In the case where the solution is supplied via a feed line  130  the weld-cleaning machine  105  usually includes a solutions reservoir. The solution is typically an electrolyte solution. The control panel  110  has controls to turn the solution pump on/off and to control the rate at which the solution is dispensed to the end-piece  200  via the feed line  130 . Alternatively, the solutions reservoir may be located in the end-piece  200 . For example, the solutions reservoir may be a replaceable solutions cartridge, which connects to the end-piece  200 . 
         [0063]    The ground connector  120  is used to ground the welded product being cleaned, by connecting the welded product to ground. 
         [0064]    The end-piece  200  is handheld by the operator of the weld cleaning system  100  and has an attachment at the tip of the end-piece  200  to clean the weld. The end-piece  200  is also commonly referred to in the industry as a wand, a torch or a handpiece. The end-piece  200  may include an ON/OFF switch to turn on or off the electrical power and/or the solution flow through the tip of the end-piece  200 . The end-piece  200  may also include a manually operated pump to dispense the solution, which is a useful option when it is not desirable to provide a powered solution pump in the weld cleaning machine  105 . The end-piece  200  and the attachment at the tip of the end-piece  200  are discussed in further detail below. 
         [0065]    It is appreciated that embodiments of the invention are not limited to the welding cleaning system  100 . For example, weld-cleaning systems such as MINI SURFOX, SURFOXT™ 204 and SURFOX™ 104 provided by Walter Surface Technologies Inc. may be used with embodiments of the invention. 
         [0066]      FIG. 2A  is a perspective view of an assembly of the end-piece  200  in accordance with an embodiment of the invention. As illustrated, the end-piece  200  includes an end-piece body  210  (not pictured), a connection tip  220 , a brush support  400  and a brush  300 . The end-piece body  210  is typically made of a non-conductive material such as plastic, rubber or any other suitable material. In this example, the connection tip  220  extends out of the end-piece body  210  for connecting with the brush support  400 . The connection tip  220  is made of a conductive material. 
         [0067]      FIG. 2B  is an exploded view of an assembly of the end-piece  200  illustrated in  FIG. 2A . As illustrated, the connection tip  220  is connectable to the brush support  400 , such that the brush support  400  can be securely fastened to the connection tip  220  and such that connection tip  220  is able to provide electricity and solution to the brush support  400 . Similarly, the brush  300  is releasably connectable to the brush support  400 . 
         [0068]    As illustrated in both  FIGS. 2A and 2B , the connection tip  220  includes a slot  225  for receiving the brush support  400 . The brush support  400  includes a tip-connecting portion  420  which may be received in the slot  225  and fastened by fastening means. Such fastening means may include screws, nuts and bolts, pins or any other suitable component which is insertable into one or more holes  228  in the connection tip  220  which then engage one or more holes  410  in tip connecting portion  420 . As illustrated, in this specific example, the tip connecting portion  420  includes two holes  410   1    410   2  (see  FIG. 4A ) and the connection tip  220  includes two holes  228   1    228   2  for receiving screws (not illustrated). In other embodiments, the brush support  400  may be connected to the connection tip  220  by other suitable means and the connection of the brush support  400  to the connection tip  220  should not be limited to these examples. 
         [0069]      FIG. 3A  is an example of the brush  300  in accordance with an embodiment of the invention. The brush  300  includes bristles  350 , a conductive connector  340  and a fluid conduit  320 . The bristles  350  may be conductive carbon fiber bristles or any other suitable bristles made out of a conductive material. The bristles  350  are attached to the conductive connector  320  to establish electric contact with the latter. For example, the bundle of bristles  350  is inserted into the conductive connector  340  and the conductive connector  340  is crimped to mechanically fasten the bristles  350  while allowing current flow to the bristles  350 . The conductive connector  340  may be made of any suitable conductive material, such as metal. The conductive connector  340  of the brush  300  is configured such that it is connectable to the brush support  400 . For instance, the brush conductive connector  340  may include one or more lugs  330  which may be used to releasably secure the brush to the brush support  400 . Although in  FIG. 3A  only a single lug  330   1  is visible, it is appreciated that in this specific example two lugs  330   1  and  330   2  are positioned on the conductive connector  340  (as illustrated in  FIG. 2B ). The conductive connector  340  also has a surface  342  of a generally circular shape. In this embodiment, the conductive connector  340  is tubular having a passage for the fluid conduit  320 . In general, the fluid conduit  320  establishes a fluid path from the brush support  400  to the bristles  350 . The fluid conduit  320  includes a tubular portion  321  with a fluid inlet  332  that is able to receive fluid from the brush support  400 . The fluid conduit  320  is typically made of a non-conductive material, such as plastic or rubber. 
         [0070]      FIG. 3B  illustrates the brush  300  with the bristles  350  omitted, a dotted line being provided to show the outline of the bristles. As illustrated in  FIG. 3B , the fluid conduit  320  extends through the conductive connector  340  and into area where the bristles  350  would typically be located. The tubular portion  321  of the fluid conduit  320  extends through the conductive connector  340  and into the area of the bristles  350 . Such a configuration distributes fluid that is received in the fluid inlet  322  of the fluid conduit  320  to the bristles of the brush. 
         [0071]      FIG. 4A  is an example of the brush support  400  in accordance with an embodiment of the invention. The brush support  400  provides a fluid path between the end-piece body  210  and the brush  300 . More specifically, the brush support  400  includes a tip connecting portion  420 , a brush-connecting portion  425  and a fluid passageway  450 . The brush support  400  (including the tip connecting portion  420  and the brush connecting portion  425 ) is typically constructed as a single piece made out of a conductive material, such as metal. 
         [0072]    As previously discussed, the tip connection portion  420  is connectable to the connection tip  220 . As illustrated in  FIG. 4A , one or more holes  410  may be provided on the tip-connecting portion  420 . The position of the one or more holes  410  is such that when the tip connecting portion  420  is received in the slot  225  of the connection tip  220 , the one or more holes  410  register with the one or more holes  228  of the connection tip  220 . When in alignment the one or more holes  410  and the one or more holes  228  would then allow for the connection tip  220  and the brush support  400  to be secured to each other by fasteners such as screws. 
         [0073]    As illustrated in  FIG. 4B , the fluid passageway  450  includes an fluid inlet  452  in the tip connecting portion  420 , such that when the tip connecting portion  420  is secured to the connection tip  220 , the fluid inlet  452  aligns with a fluid outlet  497  in the connection tip  220 , such that the connection tip  220  is able supply fluid to the brush support  400 . In other words, the brush support  400  is able to obtain fluid from the connection tip  220  of the end-piece body  210 , as the fluid outlet  497  in the connection tip  220  is connected by an end-piece fluid passageway  498  to the solution reservoir, for example, via the feed line  130 . 
         [0074]    The brush connecting portion  425  includes an opening  430  for receiving the brush  300 . The opening  430  provides a substantially circular passage  505  to a cavity  500 , where the cavity  500  is connected to the fluid passageway  450 . In other words, a continuous aperture is provided in the brush support  400  from the opening  430  on the brush-connecting portion  425  to the fluid inlet  452  on the tip connecting portion  420 . Thus, when the brush  300  is connected to the brush support  400  a fluid connection is also made. The circumference of the substantially circular passage  505  is slightly larger than the circumference of the surface  342  of the conductive connector  340 , such that at least part of the conductive connector  340  is able to fit inside and make contact with the substantially circular passage  505 . Thus, when the conductive connector  340  makes contact with the substantially circular passage  505  (and the brush support  400  in general) an electrical connection is made, which may allow for the supply of electricity from the brush support  400  to the brush  300 . 
       Connecting the Brush to the Brush Support 
       [0075]    An example of the process of connecting the brush  300  to the brush support  400  will now be discussed in further detail with references to  FIGS. 4A, 5A, 5B, 5C and 5D . 
         [0076]    One or more recesses  470  extend along the length of substantially circular passage  505  from the opening  430  to the cavity  500 . In the example illustrated, two recesses  470  are shown. The two recesses  470  are located opposite to each other. The recesses  470  have straight segments running to the bottom of the circular passage  505 , where they change direction and extend peripherally along the inner wall of the circular passage  505 . Each recess  470  runs peripherally over an arc of circle bound by an angle which is less than 180 degrees. The recesses  470  are configured such that they are able to receive respective lugs  330  on the brush  300  in a way such that the one or more lugs  330  can move along respective one or more recesses  470  when the brush is inserted into the opening  430 . As illustrated in  FIG. 4A , two recesses  470   1    470   2  are provided, such that the two recesses  470   1    470   2  are able to receive the respective lugs  330   1    330   2  when the brush  300  is inserted into the opening  430  of the brush support  400 . Essentially, the recesses  470  and the lugs  330  constitute a quick connect attachment system allowing to secure the brush  300  to the brush support  400  by inserting the brush  300  in the brush support  400  and then twisting the brush  300  to lock it in place. 
         [0077]    In  FIG. 5A  the brush  300  is positioned so the fluid inlet  322  of fluid conduit  320  and conductive connector  340  align with the opening  430  of the brush support  400 . The two recesses  470   1    470   2  also align with the respective lugs  330   1    330   2  and then a force may be applied in the direction of the arrow in  FIG. 5A  to start the insertion of the brush  300  into to the brush support  400 . 
         [0078]      FIG. 5B  illustrates the partial insertion of the conductive connector  340  and full insertion of the fluid inlet  322  of fluid conduit  320  through the opening  430  of the brush support  400 . As illustrated, the fluid inlet  322  is fully received into the brush support  400  such that fluid inlet  322  has moved past the circular passage  505  and the cavity  500  and engages (e.g., inserted into) a fluid outlet  454  on the fluid passageway  450 . As the brush  300  is inserted into the brush support  400  the two lugs  330   1    330   2  move along the respective two recesses  470   1    470   2 , which prevents the rotation of the brush  300 . 
         [0079]      FIG. 5C  illustrates the brush  300  inserted to a point where the lugs  330   1    330   2  enter the cavity  500  which is defined by the arcuate portions of recesses  470   1    470   2 . At this point, the brush  300  may then be rotated in the direction of the arrow illustrated in  FIG. 5C  (counter clockwise) to lock it in place. In general, the brush  300  is rotated until the one or more lugs  330  align with respective one or more grooves  520 . In this specific example, the brush  300  is rotated approximately 90 degrees until the two lugs  330   1    330   2  align respectively with the two groves  520   1    520   2 . During this rotation process the fluid inlet  322  remains engaged in the fluid passageway  450 . 
         [0080]    Once the one or more lugs  330  align with the respective one or more grooves  520 , then as illustrated in  FIG. 5D , the brush can slightly recede out of the brush support allowing the lugs  330  to engage the respective grooves  520 . The engagement of the lugs  330  in the respective grooves  520  locks the brush  300  against accidental rotation keeping the brush in place. Furthermore, when the lugs  330  engage the respective grooves  520  the fluid conduit  320  remains engaged in the fluid passageway  450 . 
         [0081]    An option is to provide a resilient member, such as coil spring in the cavity  505 , that urges the brush  300  out of the brush support  400  such that the lugs  330  remain locked in the grooves  520 . To remove the brush  300  from the brush support  400 , the user must first press in the brush  300  to overcome the resiliency of the spring and bring out the lugs  330  out of the grooves  520 , then twist the brush and pull it out. 
         [0082]    The above arrangement allows the brush to be conveniently removed from the brush support for replacement when the brush is worn out or for replacement with a different style brush to better fit a particular job. The releasable connection, in addition to mechanically fastening the brush to the brush support also creates an electric contact for current flow and also a fluid connection for solution to be dispensed to the brush. 
       Various Sized Brushes 
       [0083]    Although in the embodiments previous discussed only a single sized brush  300  was described brushes of different sizes may be used in some embodiments. For example, a small brush, a medium brush and a large brush may be interchangeably used where the size of the brush in general corresponds to the surface area covered by the bristles of brush. 
       Multiple Brushes 
       [0084]    Similarly, although in the embodiments previous discussed only a single brush  300  was described multiple brushes (i.e., a plurality) may be used in some embodiments. 
         [0085]      FIG. 6A  is an example of an assembly of an end-piece  200 ′ for use with two brushes  300  in accordance with an embodiment of the invention. For ease of reference, in discussing the various implementations, a “prime” (′) indicator may be included on previously introduced reference characters to indicate a variant of the previously introduced element or embodiment. The end-piece  200 ′ comprises similar elements to that of the end-piece  200  and the end-piece  200 ′ functions in a similar manner to that of the end-piece  200 . The main different in the end-piece  200 ′ when compared with the end-piece  200  is that a brush support  600  for use with up to two brushes  300 ′ is provided instead of the brush support  400  for a single brush  300 . 
         [0086]      FIG. 6B  is an example of the brush support  600  for use with the two brushes  300 ′ in accordance with an embodiment of the invention. Similar to the brush support  400 , the brush support  600  is connectable with the connection tip  220  of the end-piece body  210 . More specifically, the brush support  600  includes one or more holes  410  and a tip connection portion  420  which may be fastened to the connection tip  220  as previously discussed in relation to the brush support  400 . A brush connecting portion  625  is provided which allows for the connection of one or two brushes. The brush connecting portion  625  is similar to the brush connecting portion  425 . However, the brush connecting portion  625  includes two opening  430 ′ for receiving up to two brushes  300 ′. More specifically, a first opening  430   a ′ and a second opening  430   b ′ is provided, where each of said openings have similar components and function in a similar fashion to the opening  430 . Although not illustrated in  FIGS. 6A and 6B , the fluid provided to the brush support  600  is distributable to the two brushes  330 ′. For example, a T-joint may split the fluid received at a fluid inlet of the brush support  600  and distribute it to two fluid outlets. The use of T-joints to distribute fluid in the brush support is discussed in further detail elsewhere in this document. 
         [0087]      FIG. 7A  is an example of an assembly of an end-piece  200 ″ for use with three brushes  300 ″ in accordance with an embodiment of the invention. The end-piece  200 ″ comprises similar elements to that of the end-piece  200  and the end-piece  200 ″ functions in a similar manner to that of the end-piece  200 . The main different in the end-piece  200 ″ when compared with the end-piece  200  is that a brush support  700  for use with up to three brushes  300 ″ is provided instead of the brush support  400  for a single brush  300 . 
         [0088]      FIG. 7B  is an example of the brush support  700  for use with the three brushes  300 ″ in accordance with an embodiment of the invention. Similar to the brush support  400 , the brush support  700  is connectable with the connection tip  220  of the end-piece body  210 . More specifically, the brush support  700  includes one or more holes  410  and a tip connection portion  420  which may be fastened to the connection tip  220  as previously discussed in relation to the brush support  400 . A brush connecting portion  725  is provided which allows for the connection of one, two or three brushes. The brush connecting portion  725  is similar to the brush connecting portion  425 . However, the brush connecting portion  725  includes three opening  430 ″ for receiving up to three brushes  300 ″. More specifically, a first opening  430   a ″, a second opening  430   b ″ and a third opening  430 ″ is provided, where each of said openings have similar components and function in a similar fashion to the opening  430 . As illustrated in  FIG. 7B , the brush support  700  includes a fluid inlet  453  connected to a fluid passageway  451 , which functions similar to the fluid inlet  452  and the fluid passageway  450  in the brush support  400 . In this embodiment, a first T-joint  455  is provided which is able to distribute fluid in the passageway  450  to a second set of T-joints  456   a    456   b . The second set of T-joints  456   a    456   b  is then able to distribute fluid in the passageway  450  to the three fluid outlets  458   a ,  458   b  and  458   c . As illustrated, an additional T-joint  457  is provided such that the three fluid outlets  458   a ,  458   b  and  458   c  are able to receive fluid from either of the second set of T-joints  456   a    456   b . The three fluid outlets  458   a ,  458   b  and  458   c  function in a similar way to the fluid outlet  454 ; that is, the three fluid outlets  458   a ,  458   b  and  458   c  are engageable with respective fluid inlets of fluid conduits of the set of brush  300 ″. 
         [0089]    In the embodiments of  FIGS. 6A, 6B, 7A and 7B , the brush support  600  and the brush support  700  where both configured such that the brushes would be positioned laterally beside each other. However, the positioning of the brushes need not be in such a lateral configuration and there are many different ways the brushes may be positioned. By way of a non-limiting example, the assembly of an end-piece  200 ′″ illustrated in  FIG. 8A  and the brush support  800  illustrated in  FIGS. 8A and 8B  is an example of a different way the brushes  300 ′″ may be positioned in the brush support  800 . 
         [0090]      FIG. 8A  is an example of an assembly of an end-piece  200 ′″ for use with three brushes in a triangular configuration  300 ″ in accordance with an embodiment of the invention. The end-piece  200 ″ comprises similar elements to that of the end-piece  200 ″ and the end-piece  200 ′″ functions in a similar manner to that of the end-piece  200 ′″. The main different in the end-piece  200 ′″ when compared with the end-piece  200 ″ is that the brush support  800  positions the brushes  300 ″ in a triangular configuration. 
         [0091]      FIG. 8B  is an example of the brush support  800  for use with the three brushes  300 ″ in a triangular configuration in accordance with an embodiment of the invention. Similar to the brush support  700 , the brush support  800  is connectable with the connection tip  220  of the end-piece body  210 . More specifically, the brush support  800  includes one or more holes  410  and a tip connection portion  420  which may be fastened to the connection tip  220  as previously discussed. A brush connecting portion  825  is provided which allows for the connection of one, two or three brushes. The brush connecting portion  825  is similar to the brush connecting portion  725 . As illustrated, the brush connecting portion  825  is circular in shape and a first opening  430   a ′″, a second opening  430   b ′″ and a third opening  430   b ′″ are provided in a triangular positioning, where each of said openings have similar components and function in a similar fashion to the opening  430 . Similar to the brush support  700 , the brush support  800  includes a fluid passageway which may be configured by use of a plurality of T-joints which are able to distribute fluid in the fluid passageway to fluid outlets which are engageable with fluid inlets of the brushes  300 ′″. 
         [0092]    In the embodiments discussed in  FIGS. 2A, 2B, 6A, 6B, 7A, 7B, 8A and 8B  the end-piece body  210  and the connection tip  220  remain the same—it is only the brush supports  400   600   700   800  that change. In other words, the brush support end-piece body interface remains the same such that the end-piece body  210  can receive multiple brush support styles. The connection of brushes  300 ′  300 ″  300 ″ in the embodiments discussed in  FIGS. 6A, 6B, 7A, 7B, 8A and 8B  can be connected to the brush supports  600   700   800  similar to the process discussed in regard to connecting the brush  300  to the brush support  400  and as illustrated in  FIGS. 5A to 5D . 
         [0093]    It is appreciated that the use of multiple brushes in the weld cleaning system  100  may allow for the current supplied to be distributed over the multiple brushes, which may result in an increased lifetime of the brushes when compared to an equivalent single brush system. 
       Plug &amp; Sensors 
       [0094]      FIG. 9  illustrates an example of a plug  900  in accordance with an embodiment of the invention. The plug  900  includes a plug body  940 , which has a surface  942  of a generally circular shape. The plug also includes one or more lugs  930 . Although in  FIG. 9  only a single lug  930  is visible, it is appreciated that in this specific example two lugs are positioned on the plug body  940 . Similar to how the brush  300  is insertable into the openings of the brush supports  600   700  or  800 , the plug  900  can be inserted into one of the openings of the brush supports  600   700  or  800 . The plug also includes a fluid passageway blocker  920  which is used to block the flow of fluid out of the fluid passageway in the brush support. More specifically, the fluid passageway blocker  920  would engage the fluid outlet in the brush support. The purpose of the plug  900  is that an operator that is cleaning a weld with one of the supports  600   700  or  800  may remove one of the brushes from the set of brushes being used and replace it with the plug  900  and then still be able to cleaning the weld with one less brush without having to change the brush support. 
         [0095]    Sensors may be located in the brush support  400   600   700  or  800  for detecting whether a brush  300  or plug  900  is inserted. For instance, the small sensor may be positioned in the substantially circular passage  505  or the cavity  500  such that when the conductive connector  340  or plug body  940  makes contact with the substantially circular passage  505  the sensor detects that a brush  300  or plug  900  is inserted. A feedback signal could then be provided from the sensors to weld cleaning machine  105  to indicate that a brush  300  or plug  900  is missing and prevent operation of the weld cleaning system  100 . 
         [0096]    Sensors may also be positioned in the brush supports  400   600   700  or  800  to detect the lack of solution flow in the brush supports and to generate a feedback signal to stop the weld cleaning machine  105 . 
         [0097]    In other embodiments the brush support  400   600   700  or  800  may include a check valve which prohibits the flow of fluid if a brush  300  or plug  900  is not inserted into the brush support. 
       Bristle Pad Support Attachment 
       [0098]      FIG. 10  is an example of a brush  1000  in accordance with an embodiment of the invention. The brush  1000  is a variant of the brush  300  and the brush  1000  functions in a similar fashion and has similar components to that of the brush  300 . The main difference between the brush  1000  and the brush  300  is that the brush  1000  includes a mounting member  1010  on the surface  342 ′ of the conductive connector  340 ′. The general purpose of the mounting member  1010  is for holding in place a bristle pad support attachment which may be displaceably mounted on the conductive connector  340 ′. In this example, the mounting member  1010  is serrated; having a series of peaks  1011  and crevasses  1012 . 
         [0099]      FIG. 11A  is an example of the brush  1000  and a bristle pad support attachment  1100  in accordance with an embodiment of the invention. The bristle pad support attachment  1100  is made of a non-conductive material such as rubber or plastic. The bristle pad support attachment  1100  has two mating pieces a first piece  1101  and a second piece  1102 . 
         [0100]      FIG. 11B  illustrates the bristle pad support attachment  1100  where the first piece  1101  and the second piece  1102  are separated from each other. The first piece  1101  has a series of projections  1122  and the second piece  1102  has a series of grooves  1124 . The first piece  1101  can be connected to the second piece  1102  by aligning the series of projections  1122  with the series of grooves  1124  and pushing the first piece  1101  and the second piece  1102  together such that the projections  1122  and grooves  1124  engage each other. It is appreciated that such a configuration allows for the bristle pad support attachment  1100  to be assembled by pacing the pieces  1101  and  1102  on either side of the bristles pad and then clipping them together. 
         [0101]    The first piece  1101  and the second piece  1102  both have a generally U-shaped cavity  1111  and  1112 , respectively. The U-shaped cavities  1111 ,  1112  extend along the entire length of the pieces  1101  and  1102  except at the rear (not shown) end where the cavities acquire a semi-circular shape to closely conform to the connector  340 ′. The U-shaped cavities  1111 ,  1112  impart to the bristles pad a particular cross-sectional shape that is more desirable for a certain job. As illustrated in  FIG. 11A , the shape  1151  of the bristles pad is generally square or rectangular. As such, when the first piece  1101  and the second piece  1102  are connected to each other, the U-shaped cavities  1111 ,  1112  form a generally square or rectangular cavity. The bristle positioning attachment  1100  also includes a detent  1150  for engaging the mounting member  1010 . The detent  1150  is a tab, which is selectively engageable with anyone of the crevasses  1012 . The bristles pad support can be moved along the connector  340 ′ by applying enough force to disengage the tab  1150  from its current crevasse  1012  to relocate it in another crevasse  1012  that corresponds to the desired position of the bristles pad support. 
         [0102]      FIG. 11C  shows the bristle positioning attachment  1100  in a different position than the one shown at  FIG. 11A , in which a larger portion of the bristles pad is exposed to provide the bristles pad with increased flexibility. 
         [0103]      FIG. 12  shows a bristles pad support configured to impart to the bristles pad a circular cross-section. 
         [0104]      FIG. 13A, 13C  illustrate is yet another variant in which the bristles pad support is configured to spread out the bristles. The bristles pad support can be moved as discussed earlier along the connector &#39; 340 , as shown by the arrow in  FIG. 13C . 
         [0105]      FIG. 13B  illustrates the bristle the constituent elements of the bristles pad support, shown separated from one another. 
         [0106]      FIGS. 14A-B  depict an embodiment of an end-piece  3000 , according to another variant. The end-piece  3000  functions similarly to the end-piece  200  and has components similar thereto. Specifically, the end-piece  3000  comprises an end-piece body  3002  and a brush  3006 . The end-piece body  3002  is made of a non-conductive material such as plastic, rubber or any other suitable material. 
         [0107]    The brush  3006  comprises a pad of conductive bristles  3004  that are electrically connected via the brush support to the power supply of the weld cleaning apparatus. Electrolytic solution is supplied to the bristles pad  3004  in the same fashion as described with earlier embodiments. The bristles pad  3004  may be made if conductive carbon fiber bristles or any other suitable bristles made out of a conductive material. 
         [0108]    The end-piece  3000  comprises a bristles pad support system  3008 , which supports the bristles pad  3004 , and optionally can be used to impart to the bristles pad  3004  a desired cross-sectional shape to better suit the particular weld cleaning job. The bristle support system  3008  is releasably attached to the end-piece body  3002  by using the arrangement illustrated in  FIGS. 3A and 3B , for example. 
         [0109]    With further reference to  FIGS. 15A-B , in a first embodiment the bristles pad support  3008  is implemented as a stack of twist rings  3010 . Each twist ring  3010  comprises upper and lower cylindrical portions  3012 ,  3014 , threads  3016 , female detents  3018  and male detents  3019 . Each of the cylindrical portions  3012 ,  3014 , has a cylindrical wall, which defines an aperture about its respective center, and the cylindrical portions  3012 ,  3014  are concentric. The upper cylindrical portion  3012  rests on the lower cylindrical portion  3014 , and has a diameter, which is less than the diameter of the lower cylindrical portion  3014 . More specifically, the diameter of the upper cylindrical portion  3012  of the twist support ring  3010  is such that it can fit into the lower cylindrical portion  3014  of a second twist ring  3010 . 
         [0110]    The upper cylindrical portion  3012  has one or more threads  3016  which are distributed along an outer face of the cylindrical wall of the upper cylindrical portion  3012 , and which span an entire height of the upper cylindrical portion  3012 . Typically, the upper cylindrical portion  3012  will have two or more thread segments  3016  which are equally distributed on the cylindrical portion  3012 . The threads  3016  are implemented as grooves and terminate each with a female detent  3018 , which is defined by with rounded shallowed area. 
         [0111]    With continued reference to  FIG. 15B , the twist ring  3010  comprises at least one male detent  3019  positioned on an inner wall  3013  of the lower cylindrical portion  3014 . The male detents  3019  are configured for slidably mating with the threads  3016 , such that a first twist ring  3010  can be threadedly engaged with a second twist ring  3010 , the engagement being produced by the male detents  3019  slidably running in the threads  3016 . 
         [0112]    The male detents  3019  can be forcefully pushed to interlock with the female detents  3018 . The interlocking of the male detents  3019  with the female detents  3018  locks the twist rings against unwanted rotation and ultimately separation. 
         [0113]    The variant shown in  FIG. 15C  the lower cylindrical portion  3014  has a knurled surface  3024  including a series of indentations to allow the fingers of the operator to get a better grip. 
         [0114]    The variant shown in  FIG. 16A  has an extended upper cylindrical portion  3032  allowing inter-engaged twist rings to telescope over a longer distance. In the example shown, the upper cylindrical portion  3032  has multiple female detents defining a number of positions in which a male detent  3019  can be held captive, thus allowing locating the twist rings at selected positions one with relation to the other. 
         [0115]      FIG. 16B  shows a variant with a knurl, similar to the variant at  FIG. 15C . With reference to  FIGS. 18A-B , the bristles pad support is implemented as a stack of friction rings  3050 . Each friction ring  3050  comprises upper and lower cylindrical portions  3052 ,  3054  that have no threads. The friction rings  3050  have female detents in the form of recesses  3058  for engaging the male detents in the form of projections  3059 . The diameter of the upper cylindrical wall  3052  is selected such that when the support rings are inter-engaged the male detents  3059  frictionally engage the outer surface of the upper cylindrical wall  3052 . When the projections  3059  snap in the female detents  3058 , the support rings are locked in place against unwanted separation. To separate the support rings they are twisted with sufficient force to unseat the male detents  3059  from the female detents  3058  and the friction rings can then pulled apart. 
         [0116]    Note that the position of the female detents  3058  and position of the male detents  3059  may be reversed; the male detents may be formed on the upper cylindrical wall while the female detents are formed on the internal cylindrical wall  3053 . 
         [0117]    With reference to  FIG. 18C , indentations  3064  can be provided for improved grip. 
         [0118]      FIGS. 19A and 19B  show a further variant of the friction ring  3050  that is extended to provide multiple detent receiving positions. 
         [0119]    A further variant of the bristles pad support is illustrated in  FIG. 20  that uses magnetic force to retain the support rings. A band  3099  of ferromagnetic material is provided inside the support ring  3099  that engages magnets  3098  of an adjacent support ring  3099 . 
         [0120]    In use, the support rings in  FIGS. 14A, 15A, 15B, 15C  are stacked, the number of support rings in a stack is selected such that the stack covers the entire length of the bristles pad less a small exposed part at the tip, which is the working part of the brush. If desired, the operator can remove one or more of the rings from the stack to expose a longer part of the bristles pad for applications where a brush with more flexibility is desired. As the bristles wear out, they get shorter. To keep the same exposed length, the operator removes a support ring from the stack. This is accomplished by twisting off the outermost support ring and removing it from the stack. In the embodiment shown at  FIGS. 15A, 15B and 15C , the operator holds the stack in his hand and unscrews the outermost ring by applying sufficient force to dislodge the male detents  3019  from the female detents  3018 . The support ring so removed is a throw away item. Alternatively, the support rings can be retained for reuse. For instance, there may be applications where the operator needs to remove a number of support rings to expose a larger portion of the bristles and when the job is completed, the operator puts the rings back together to reassemble the original stack. 
         [0121]    The operation of the support rings  14 B,  16 A,  16 B is somewhat different. Since the support rings  3040  can be set at different positions, one with relation to the other, the stack will typically have fewer support rings  3040 . The stack shown in  FIG. 14B  has three support rings  3040  but even two support rings  3040  could be sufficient. In contrast to the earlier example, the stack of rings  3040  is fully expanded, in other words the projections (male detents)  3019  are seated in the outermost female detents  3038 . As the bristles wear out, the support rings  3040  are progressively closed, the female detents  3038  defining respective positions in which the stack length is diminished in stages. The last adjustment position is the one where the support rings  3040  are fully closed. If the bristles need to be further exposed, at that point, the outermost support ring  3040  is removed from the stack and thrown away. 
         [0122]    The operation of the friction support rings  3050  shown in  FIGS. 18A, 18B, 18C, 19A and 19B  is similar as in the above examples, with the difference that there are no threads to guide the motion of the support rings as they are being separated. The operator therefore needs to fiddle with the support rings until the male detents snap in the female detents that locate the support rings  3050  in the desired relative positions. 
         [0123]      FIGS. 17A-B  show stacks made up of friction support rings  3060 ,  3080 . 
         [0124]    With reference to  FIG. 21 , another embodiment of the end-piece  3000  is depicted. In this embodiment, the end-piece  3000  comprises an end-piece body  3100  for retaining the bristles pad  3004 , a bristles pad support  3104  made up of a stack of breakaway elements  3102  which surround the bristles pad  3004 . The end-piece body  3100  is similar to the end-piece body  3002 . 
         [0125]    The breakaway elements  3102  are shaped as frusto-conical sections the smaller end of one section fitting in the larger end of the adjacent one. The breakaway elements  3102  are linked by frangible tabs that can be broken to separate the elements  3102  from each other. 
         [0126]    Removing one or more elements  3102  by snapping the frangible tabs linking two proximate elements  3102  has the effect of shortening the bristles pad support  3104 . As the bristles pad wears out, the breakaway elements  3102  are snapped off to keep the exposed tip of the bristles pad at the desired length. 
         [0127]    While the breakaway elements  3102  have been described as frusto-conical portions, these may be implemented in any other suitable fashion, including cylindrical elements, pyramidal elements, cubic elements, or any variation thereof. 
         [0128]    In a variant, the end-piece  3000  is provided with a bristles pad shaping spout  3200 , which imparts to the bristles pad a particular profile. With reference to  FIGS. 22A-E , five variants ( 3210 ,  3220 ,  3230 ,  3240 ,  3250 ) of the spout  3200  are shown. For example, the spout  3200  can be configured such as to spread out the bristles pad to provide a brush with a larger cover area. The spout can be mounted to any one of the support rings discussed above and would typically constitute the outermost support ring in the stack. That support ring is normally not a throw away item and can be reused. When the bristles pad support is to be shortened to account for bristles wear, the outermost support ring, the one with the spout is removed, the next ring is also removed and thrown away and the support ring with the spout put back in place. 
         [0129]    To allow positioning the bristles pad in the desired angular orientation the support ring carrying the spout can be made rotatable relative to the adjacent support ring about the longitudinal axis of the brush. Advantageously, detents can be provided at different angular orientations, such that the spout can be set and maintained in the angular orientation that is the most convenient to the user. 
         [0130]      FIG. 23  illustrates yet another example of implementation where the bristles pad support  3500  can be bent to orient the working end of the brush at an angle relative to the end-piece (not shown). The bristles pad support  3500  includes three sections  3502 ,  3504  and  3506  that are articulated, in other words they can be set at an angle one with relation to the other. The section  3502  has at its lower end a ball shaped part  3508 , which is a male ball shaped part. The section  3504  has at its upper end a female ball shaped part  3510 . The female ball shaped part  3510  receives the male ball shaped part  3508  to form a ball joint allowing the sections  3502  and  3504  to be angularly oriented as desired. The fit between the female ball shaped part  3510  and the male ball shaped part  3508  is a frictional fit such that once the sections  3502  and  3504  are set in the desired orientation they resist forces exerted on the ball joint during normal use of the brush. To change the angular orientation, a higher effort is required to overcome the friction. The interconnection between the sections  3504  and  3506  also uses a ball joint and works as discussed above. 
         [0131]    Sections  3502 ,  3504  and  3506  are made of plastic material that has sufficient rigidity and resilience such that the sections  3502 ,  3504  and  3506  can be snap fitted to one another. In other words by pulling two sections away, say sections  3502  and  3504  with sufficient force, the female ball shaped part  3504  will spread out slightly to allow the male shaped part  3508  to be slip out of the ball joint. The assembly is the reverse that is the sections  3502  and  3504  are pushed against each other such that the female ball shaped part  3508  resiliently spreads out sufficiently to accept the male ball shaped part  3508 . The ability of the sections  3502 ,  3504  and  3506  to be snap fitted to each other allows assembling the bristles pad support  3500  of the desired length and to progressively remove sections as the bristles pad wears out. 
         [0132]    In  FIG. 23 , the bristles pad support  3500  is shown as being straight, in other words it extends along the longitudinal axis of the hand piece. The longitudinal axis is shown by the dotted line  3512 .  FIG. 24  illustrates the bristles pad support  3500  as being bent at an angle relative to the longitudinal axis  3512 . The configuration imparts a bent to the bristles pad to adapt its shape to better suit a particular job, which may be more difficult to perform with a bristles pad that is straight. 
         [0133]      FIG. 25  is yet another embodiment of the bristles pad support which uses a lipstick case-like mechanism with telescoping parts to adjust the length of the support along the bristles pad. The bristles pad support  3900  has a connector  4000  that supports a bristles pad  4002 , shown in dotted lines. As with the previous embodiments the connector  4000  physically carries the bristles pad, provides an electrical supply connection to the bristles and also supplies electrolyte through the conduit  4004 . The body of the connector  4000  is generally cylindrical and has a pair of pins  4006  projecting laterally. Only one pin  4006  is shown in the drawings, the other pin being generally opposite the pin  4006 . 
         [0134]    The connector  4000  and the bristles pad  4002  are slidably received in an inner tube  4008 , which has a pair, or opposite Z-shaped slots  4010 . The dimensions of the various pieces are selected such that the pins  4006  slidably fit in the respective slots  4010  and slightly project therefrom. 
         [0135]    The inner tube  4008  is slidably received in an outer tube  4012 . The outer tube  4012  has a pair of internal helical grooves  4014  dimensioned to receive the projections  4006  that extend through the slots  4010 . 
         [0136]    The connector  4000  is secured to the hand piece  4016  in the usual fashion to establish the desired electrical and fluid connections. The hand piece  4016  can be the same as the examples provided earlier with the exception that it has a longer neck  4018  to allow the bristles pad support  3900  to move back and forth in the direction along the arrow  4020 . 
         [0137]    The outer tube  4012  is mounted on the inner tube  4008  and receives the pins  4006  in the grooves  4014 . The outer tube  4012  can be provided with a knurl for a better grip. When the operator rotates the outer tube  4012 , the rotation causes a longitudinal displacement of the inner and outer tubes  4008 ,  4012  about the connector  4000  such as to expose more or less of the bristles. This bristles pad support  3900  can be designed of sufficient length such as to be able to completely enclose the bristles pad, such that when the weld cleaning apparatus is not being used, the bristles pad support is fully extended to protect the bristles pad. 
         [0138]    The bristles pad with the bristles pad supports shown in  FIGS. 14A-25  can be made available as a unit such that when the bristles pad is worn out, it is removed from the end-piece and replaced by a new unit. In other words, the user would purchase a new unit consisting of a bristles pad and the bristles pad support and simply attach it to the end-piece. Such unit can use the connector  340  discussed earlier. In this form of implementation, the body of the connector  340  is configured to act as a bristles pad support carrier. In the example of the bristles pad support  3008  the twist ring  3020  which is the first twist ring in the stack is mounted to the connector  340 . The aperture of the first twist ring is dimensioned to receive the connector  340  therein. To avoid separation, the twist ring may be adhesively or mechanically fastened to the connector  340 . In this fashion, when the bristles pad is worn out, the twist ring that is secured to the connector  340  is twisted to separate the connector  340  from the end-piece. The connector  340 , the twist ring and the bristles pad stub is thrown out. The new unit is then installed on the end-piece by inserting the connector  340  in the end-piece and locking it in place. 
         [0139]    All documents mentioned in the specification are herein incorporated by reference.