Patent Publication Number: US-10307905-B2

Title: Tool coupling arrangement

Description:
TECHNICAL FIELD 
     The disclosure is directed to a coupling for joining a handle and a tool head, and more specifically, to an arrangement and method joining a handle to tool head that negates the need for an interference, press-fit relationship between mating components. 
     BACKGROUND 
     The current method of joining a handle and head involves drilling a hole in the end grain of a tapered wood section of handle. The tapered wood section of handle is then shrouded in a matching steel ferrule. The shank of the tool head is then pressed into the bored hole creating a press fit to retain the head to handle. However, this method requires a high level of precision in the relationships between mating components. For example, the press fit relies on a proper cross-sectional area relationship between the bore diameter and tool head shank. 
     Another issue that occurs with the known method outlined above concerns durability of the connection. More specifically, as the wood portion absorbs liquid, shrinks, or even rots, the press fit can be compromised, causing the shank to move within the wood handle or even rendering the tool inoperable. 
     Other coupling methods include the use of a standard fastener such as a nail or rivet that goes through the ferrule; handle material and hole in the tool shank. However, because the nail or rivet is introduced through the wood handle, the issues relating to durability of the tool may be effect. While epoxy adhesive to join the tool shank to the handle has also been known, over time, the epoxy can degrade. 
     SUMMARY 
     In a first embodiment, a coupling for an elongated handle and a tool head is disclosed. The coupling includes a plug member, a ferrule, and a pin member. The plug member further comprises an elongated passage formed therein receives a tool head shank of the tool head. The elongated passage is in communication with a pair of aligned plug member openings formed through the plug member. The ferrule includes a pair of aligned ferrule openings. When the plug member is partially received within the ferrule, the plug member openings align with the ferrule openings. The pin member extends through the aligned ferrule openings and the plug member openings and through an opening of the tool head shank when the tool head shank is mounted in the elongated passage. The ends of the pin member are bent at an angle to an axis extending through the elongated passage to secure the tool head shank to the plug member and ferrule. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Exemplary embodiments of the present disclosure will now be described in greater detail with reference to the attached figures, in which: 
         FIG. 1  is a partially exploded view of a first exemplary arrangement of a tool coupling assembly; 
         FIG. 2  is a partial cross-sectional view of a plug member and a tool head shank; 
         FIG. 3  is a perspective view of metal ferrule assembled to the plug member of  FIG. 2 ; 
         FIG. 4  is a perspective view of the metal ferrule being mounted to the plug member of  FIG. 2 ; 
         FIG. 5  is a plan view of the metal ferrule mounted to the plug member of  FIG. 2 , taken along axis A-A; 
         FIG. 6  is a perspective view of the metal ferrule mounted to the plug member of  FIG. 2 , with an attachment pin in a securing position; 
         FIG. 7  is an elevational view of the metal ferrule mounted to the plug member of  FIG. 2 , with the attachment pin in the securing position; 
         FIG. 8  is a perspective view of the tool coupling assembly of  FIG. 1  in an assembled configuration; 
         FIG. 9  is a partially exploded view of a second exemplary arrangement of a tool coupling assembly; 
         FIG. 10  is a perspective view of the tool coupling assembly of  FIG. 9  in an assembled configuration; 
         FIG. 11  is a partial cross-sectional view of the tool coupling assembly from encircled area  11  of  FIG. 10 ; 
         FIG. 12  is an end view of the tool coupling assembly of  FIG. 9 ; 
         FIG. 13  is a cross-sectional view of the tool coupling assembly taken along lines  13 - 13  of  FIG. 12 ; and 
         FIG. 14  is a top view of the tool coupling assembly of  FIG. 9 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the discussion that follows and also to the drawings, illustrative approaches to the disclosed assemblies and methods are shown in detail. Although the drawings represent some possible approaches, the drawings are not necessarily to scale and certain features may be exaggerated, removed, or partially sectioned to better illustrate and explain the present disclosure. Further, the descriptions set forth herein are not intended to be exhaustive or otherwise limit or restrict the claims to the precise forms and configurations shown in the drawings and disclosed in the following detailed description. 
     Described herein are tool coupling assemblies, various components for use in same, and a method of constructing the tool coupling assembly. The components disclosed herein provide an improved assembly, while minimizing the need for tight manufacturing tolerances. While shown in connection with a particular tool head design, it is understood that various tools heads are envisioned. 
     Referring to  FIG. 1  a tool assembly  10  includes a tool head  12 , an elongated handle  14  and a coupling assembly  16 . The tool head  12  may be any type of tool head. In one exemplary arrangement, the tool head  12  is configured as hoe. However, it is understood that other push/pull tool head  12  designs, such as rakes, scrapers, edgers, cultivators, and hooks, as well as hand tools such as, for example, trowels, are also contemplated in this disclosure. 
     The tool head  12  has a body  18  configured to perform a function, e.g., dig, rake, etc. The tool head body  12 , further includes a tool head shank  20  having a first end  22  fixedly connected to the tool head  12 , and a second free end  24  (as best seen in  FIG. 2 ). In one exemplary arrangement, first end  22  is integral with the tool head  12 . The tool head shank  20  may have a variety of cross-sectional shapes. The tool head body  12  and the tool head shank  20  is made from a rigid and hard material, such as steel, that is generally not deformable. The tool head shank  20  further comprises an opening  25  extending therethrough, as best seen in  FIG. 2 . 
     The handle  14  has an upper end  26  and a lower end (not shown). The upper end  26  includes an insertion section  30  and a grasping section  32 . The insertion section  30  is defined by a distal end  34 . The insertion section  30  is fixedly attached to the grasping section  32  and is sized to be smaller than the grasping section  32 , such that an engagement flange  33  is formed where the handle attaches to the insertion section  30 . In one exemplary arrangement, the insertion section  30  tapers inwardly toward a central axis extending through the handle  14  from the engagement flange  33  toward the distal end  34 . A notch  36  may also be formed in the insertion section  30 , extending from the distal end  34  along part of the insertion section  30 , as shown in  FIGS. 1 and 5 . The notch  36  is configured to receive a wedge member  38 . The wedge member  38  allows for providing a tight fitting press fit engagement with a portion of the coupling assembly  16 , as will be discussed in further detail below. 
     Referring to  FIGS. 2-4 , details of the coupling assembly  16  will be discussed. Coupling assembly  16  further comprises a plug member  40 , a ferrule  42  and a pin member  44 . In one exemplary arrangement, the plug member  40  is configured as a two-piece clam shell design, where the two mating pieces  40   a,    40   b  combine to form the plug member  40 . While shown as two separate pieces, in one exemplary arrangement, mating pieces  40   a,    40   b  may be joined with a hinge (not shown). 
     Plug member  40  further comprises a channel  46  extending from a first end  48  to a second end  50  of the plug member  40 . The channel  46  is configured to have a complementary shape to the tool head shank  20 , such that the tool head shank  20  may be selectively received within the channel  46 , as shown in  FIG. 2 . Disposed on either side of channel  46  are connector elements  52 ,  54 . In one exemplary arrangement, connector elements  52 ,  54  are configured as attachment tabs  52  and complementary openings  54 . In one exemplary arrangement, each mating piece  40   a,    40   b  includes at least one pair of connector elements  52 ,  54 , with one attachment tab  52  disposed on one side of the channel  46 , and one opening  54  disposed on the other side of the channel  46 . In the particular arrangement shown, there are two pairs of connector elements  52 ,  54  with the attachment tabs  52  arranged on opposing sides of the channel  46 , and the openings  54  also arranged on opposing sides of the channel  46 . The mating pieces  40   a,    40   b  are joined together such that the connector elements  52 ,  54  of the mating piece  40   a  mate with and join the connector elements  52 ,  54  of the mating piece  40   b.  When joined in this manner, the channels  46  of the mating pieces  40   a,    40   b  cooperate for form an elongated passage, as shown in  FIG. 5 , for example. It is understood, however, that other connector elements  52 ,  54  are contemplated. 
     Each mating piece  40   a,    40   b  also include an opening  56  extending therethrough. The plug member opening  56  aligns with the opening  25  disposed within tool head shank  20 , when the tool head shank  20  is seated within the elongated passage formed by channels  46 . 
     The plug member  40  includes a body section  58  and an end section  60 . The outside diameter of the body section  58  is sized to be smaller than the outside diameter of the end section  60  such that a retaining edge  62  is formed where the end section  60  joins the body section  58 . The outside surface of the body section  58  on each mating piece  40   a,    40   b  of the plug member  40  further comprises a retaining groove  64 , best seen in  FIG. 4 . The retaining groove  64  extends from the plug member opening  56  to the end section  60 . The retaining groove  64  is configured to receive a portion of the pin member  44 , as will be discussed in further detail below. 
     The plug member  40  may be constructed of a suitable polymer material which allows for ease of manufacturing the channel  46 , connector elements  52 ,  54  and/or retaining groove  64 . An example of a suitable material includes polymers with a high modulus of elasticity. Further examples include, but are not limited to, nylon, polycarbonate, flexible polyvinyl chloride (PVC), plyethylene terephthalate (PET); acrylonitrile-butadiene-styrene (ABS) and/or other thermoplastic materials. 
     The ferrule  42  is configured as a sleeve having a plug member end  66  and a handle end  68 , with a body member  70  therebetween. The ferrule  42  further includes ferrule openings  72  extending through the body member  70 , positioned closer to the plug member end  66  and handle openings  74  (shown in  FIG. 8 ) also extending through the body member  70 , disposed closer to the handle end  68 . In one exemplary arrangement, the ferrule openings  72  are oriented approximately 90° from the handle openings  74 . The body member  70  of the ferrule is configured with a slight taper such that the body member  70  extends inwardly toward a central axis from the handle end  68  to the plug member end  66 . 
     The ferrule  42  may be constructed of a metal material. In one exemplary arrangement, the ferrule  42  is constructed of steel that allows for some selective deformation, as explained below. 
     A method of assembling a tool handle to a tool head using coupling assembly  16  will now be described. Referring to  FIG. 2 , the plug member  40  is first opened such that the mating components  40   a,    40   b  are separated from one another to expose channel  46 . The tool head shank  20  is inserted into the channel  46  of a first of the mating components  40   a,  with the opening  25  of the tool head shank  20  aligning with one of the plug member openings  56  of the first of the mating components  40   a.  Next, the second of the mating component  40   b  is mounted to the first of the mating components  40   a,  so as to capture the tool head shank  20  therebetween. The connector elements  52 ,  54  of the mating components  40   a,    40   b  are then engaged together. 
     Next, referring to  FIGS. 3 and 4 , the ferrule  42  is slid onto the plug member  40 . This action compresses mating components  40   a,    40   b  together, securing the tool head shank  20  therein. The plug member end  66  abuts against the retaining edge  62  of the end section  60  of the plug member  40 . The ferrule opening  72  is aligned with the plug member opening  56 . 
     Once the ferrule  42  is fully seated on the plug member  40 , the pin member  44  is inserted through the aligned ferrule openings  72 /plug member openings  56 /opening  25 , as shown in  FIG. 3 . The pin member  44  may be constructed of low carbon steel or other suitable alloy material. Next, ends  76  of the pin member  44  are bent approximately 90° toward the tool head  12 . When bent in this manner, the ferrule  42  is deformed into the retaining grooves  64  of the plug member  40  as best shown in  FIGS. 6-8 . The deformation of the ferrule  42  in this manner crimps the ferrule  42  onto the plug member  40  and retains the tool head  12  to the ferrule  42 . Once assembled in this manner, the tool head  12  can only be pulled from the ferrule  42  by shearing the pin or propagating a fracture around the ferrule opening  72 . 
     Once the ferrule  42  is attached to the plug member  40 , the handle  14  is mounted to the ferrule  42 . More specifically, referring to  FIG. 1 , the wedge member  38  is partially inserted into the notch  36  so as to seat the wedge member  38  within the notch  36 . The wedge member  38  has a triangular cross-sectional shape such that a first end is wider than a second end. Thus, the second end is disposed within the notch  36  first. Next, the insertion section  30  of handle  14  is inserted into the handle end  68  of the ferrule  42  until an edge  78  of the ferrule  42  is seated against the engagement flange  33 . As the insertion section  30  is seated within the ferrule  42 , the wedge member  38  is driven further into the notch  36  when it contacts the end  80  ( FIG. 2 ) of the plug member  40 , thereby expanding the insertion section  30  of handle  14  due to the triangular cross-section shape of the wedge member  38 . This action serves to frictionally retain the insertion section  30  against the interior walls of the ferrule  42 . Once the handle  14  is seated within the ferrule  42 , a fastening element may be inserted through handle openings  74 . 
     An alternative arrangement of a coupling assembly  116  is illustrated in  FIGS. 9-14 . For ease of reference, elements relating to the tool head  12  and elongated handle  14  utilize the same reference numbers above. Coupling assembly  116  further comprises a plug member  140 , a ferrule  142  and a pin member  144 . In one exemplary arrangement, the plug member  140  is configured as a two-piece clam shell design, where the two mating pieces  140   a,    140   b  combine to form the plug member  140 . 
     Plug member  140  further comprises a channel  146  extending from a first end  148  to a second end  150  of the plug member  140 . The channel  146  is configured to have a complementary shape to the tool head shank  20 , such that the tool head shank  20  may be selectively received within the channel  146 , as shown in  FIG. 11-13 . Disposed on either side of channel  146  are connector elements  152 ,  154  (best seen in  FIG. 9 ). In one exemplary arrangement, connector elements  152 ,  154  are configured as attachment tabs  152  and complementary openings  154 . In one exemplary arrangement, each mating piece  140   a,    140   b  includes at least one pair of connector elements  152 ,  154 , with one attachment tab  152  disposed on one side of the channel  146 , and one opening  154  disposed on the other side of the channel  146 . In the particular arrangement shown, there are two pairs of connector elements  152 ,  154  with the attachment tabs  152  arranged on opposing sides of the channel  146 , and the openings  154  also arranged on opposing sides of the channel  146 . The mating pieces  140   a,    140   b  are joined together such that the connector elements  152 ,  154  of the mating piece  140   a  mate with and join the connector elements  152 ,  154  of the mating piece  140   b.  When joined in this manner, the channels  146  of the mating pieces  140   a,    140   b  cooperate for form an elongated passage, as shown in  FIG. 11 , for example. It is understood, however, that other connector elements  152 ,  154  are contemplated. 
     Each mating piece  140   a,    140   b  also include a mount groove  156   a,    156   b  extending transverse to the channel  146 . The mount grooves  156   a,    156   b  are best seen in  FIGS. 11-13 . More specifically, the mount grooves  156   a,    156   b  each extend from channel  146  and extend inwardly through the cross-section of each mating piece  140   a,    140   b.  The mount grooves  156   a,    156   b  are configured to receive the pin member  144  therein, as will be explained in further detail below. In one exemplary arrangement, the mount grooves  156 ,  156   b  do not extend all the way through the respective mating pieces  140   a,    140   b  of the plug member  140 , such that the mount grooves  156   a,    156   b  are not opened to the outside surface of the mating pieces  140   a,    140   b.  Alternatively, the mount groves  156 ,  156   b  may extend through the cross-section of each mating piece  140   a,    140   b  for ease of manufacturing. The mount grooves  156   a,    156   b  are configured to align with one another, as well as align with the opening  25  disposed within tool head shank  20 , when the tool head shank  20  is seated within the elongated passage formed by the mating channels  146 . 
     The plug member  140  further includes a body section  158 , an end section  160  and an intermediate section  161  therebetween. The outside diameter of the body section  158  is sized to be larger than the outside diameter of the end section  160  and the intermediate section  161 , such that the plug member  140  tapers inwardly toward the a central axis extending through the plug member  140 . The outside diameter of the intermediate section  161  is sized to be smaller than the outside diameter of the end section  160  such that a retaining edge  162  is formed where the end section  160  joins the intermediate section  158 . 
     The plug member  140  may be constructed of a suitable polymer material which allows for ease of manufacturing the channel  146 , connector elements  152 ,  154  and/or mount grooves  156   a,    156   b.  Suitable materials include, but are not limited to, thermoplastic elastomer, polycarbonate, flexible polyvinyl chloride (PVC), polyurethane, and/or rubber material. 
     The ferrule  142  is configured as a sleeve having a plug member end  166  and a handle end  168 , with a body member  170  therebetween. Unlike ferrule  42 , ferrule  142  does not include ferrule openings extending through the body member  170 , but does include a handle opening  174  (shown in  FIG. 9 ) extending through the body member  170 , disposed closer to the handle end  168 . In one exemplary arrangement, the handle openings  174  are oriented approximately 90° from the axis that the channel  146  of the plug member  140  lies. The ferrule  142  may be constructed of a metal material. In one exemplary arrangement, the ferrule  142  is constructed of steel that allows for some selective deformation, as explained below. 
     A method of assembling a tool handle to a tool head using coupling assembly  116  will now be described. Referring to  FIGS. 9-11 , the plug member  140  is first opened such that the mating components  140   a,    140   b  are separated from one another to expose channel  146 . In one exemplary arrangement, the tool head shank  20  is inserted into the channel  146  of a first of the mating components  140   a,  with the opening  25  of the tool head shank  20  aligning with the mount groove  156   a  of the first of the mating components  40   a.    
     Next, the pin member  144  is directed through the tool head shank  20  and secured within the mount groove  156   a.  When this is completed the tool head shank  20  is operatively connected to the first of the mating pieces  140   a  of the plug member  140 . Alternatively, the pin member  144  may be disposed within the mount groove  156   a  and the tool head shank  20  may be directed over the pin member  144  with the opening  25  of the tool head shank  20  receiving the pin member  144  therein as the tool head shank  20  is directed into the channel  146 . 
     Once the tool head shank  20  is secured to one of the mating pieces  140   a,  the second mating piece  140   b,  is then positioned over the first mating piece  140   a,  such that the mount groove  156   b  of the second mounting piece  140   b  is mounted onto the pin member  144 , with the tool shank  20  being disposed within the channel  146 . The connector element  152 ,  154  of the respect mating pieces  140   a,    140   b  are engaged in either a frictional engagement or snap fit arrangement, securing the two mating pieces  140   a,    140   b  together to trap the tool head shank  20  within the plug member  140 . In this arrangement, the pin member  144  is sized to have a length is equal to or slightly less than a distance between the ends  175   a,    175   b  of the mount grooves  156   a,    156   b,  when the mating pieces  140   a,    140   b  are joined together, such that the ends of the pin member  144  do not extend outwardly from an outer surface of the plug member  140 . 
     Once the plug member  140  is assembled, the ferrule  142  is slid onto the plug member  140 . This action will further compress the mating components  140   a,    140   b  together, securing the tool head shank  20  therein. The plug member end  166  is positioned adjacent the retaining edge  162  of the end section  160  of the plug member  140 . Once positioned, the plug member end  166  is crimped around the body section  158  and intermediate section  161  and engaged with the retaining edge  162 , as shown, for example, in  FIG. 11 . The end section  160  of the plug member  140  protrudes from the ferrule  142 . 
     Once the ferrule  142  is attached to the plug member  140 , the handle  14  is mounted to the ferrule  142 . In one exemplary arrangement, the wedge member  38  is partially inserted into the notch  36  so as to seat the wedge member  38  within the notch  36 . Next, the insertion section  30  of handle  14  is inserted into the handle end  168  of the ferrule  142  until an edge  178  of the ferrule  142  is seated against the engagement flange  33  of the handle  14 . As the insertion section  30  is seated within the ferrule  142 , the wedge member  38  is driven further into the notch  36  when it contacts the end  180  ( FIG. 11 ) of the plug member  140 , thereby expanding the insertion section  30  of handle  14  to frictionally retain the insertion section  30  against the interior walls of the ferrule  142 . Once the handle  14  is seated within the ferrule  42 , a fastening element  182  may be inserted through handle openings  174 . 
     It will be appreciated that the tool coupling assemblies and methods described herein have broad applications. The foregoing embodiments were chosen and described in order to illustrate principles of the methods and apparatuses as well as some practical applications. The preceding description enables others skilled in the art to utilize methods and apparatuses in various embodiments and with various modifications as are suited to the particular use contemplated. In accordance with the provisions of the patent statutes, the principles and modes of operation of this disclosure have been explained and illustrated in exemplary embodiments. 
     It is intended that the scope of the present methods and apparatuses be defined by the following claims. However, it must be understood that this disclosure may be practiced otherwise than is specifically explained and illustrated without departing from its spirit or scope. It should be understood by those skilled in the art that various alternatives to the embodiments described herein may be employed in practicing the claims without departing from the spirit and scope as defined in the following claims. The scope of the disclosure should be determined, not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. It is anticipated and intended that future developments will occur in the arts discussed herein, and that the disclosed systems and methods will be incorporated into such future examples. Furthermore, all terms used in the claims are intended to be given their broadest reasonable constructions and their ordinary meanings as understood by those skilled in the art unless an explicit indication to the contrary is made herein. In particular, use of the singular articles such as “a,” “the,” “said,” etc. should be read to recite one or more of the indicated elements unless a claim recites an explicit limitation to the contrary. It is intended that the following claims define the scope of the invention and that the method and apparatus within the scope of these claims and their equivalents be covered thereby. In sum, it should be understood that the invention is capable of modification and variation and is limited only by the following claims.