Abstract:
A coil terminal has a winding section comprising an end of coiled wire wound therearound. The winding section is bent relative to a remaining section of the coil terminal. The winding section has a proximal wire engagement portion and a distal wire engagement portion spaced away from each other in a longitudinal direction of the winding section, and an intermediate region disposed between the proximal wire engagement portion and the distal wire engagement portion. The wire end is extended in the intermediate region without being wound around the intermediate region.

Description:
BACKGROUND 
       [0001]    1. TECHNICAL FIELD 
         [0002]    The invention relates to a coil terminal and an electromagnetic relay including the coil terminal. 
         [0003]    2. RELATED ART 
         [0004]    Conventionally, there has been disclosed an electromagnetic relay in, for example, JP 2000-260284(A), which comprises a spool  2 , a coil of wire  2   a  wound around the spool  2 , and coil terminals  12  and  13  around which opposite ends of the coil are wound or tangled. 
         [0005]    In this electromagnetic relay, the tangled ends of the coil  2   c  are soldered to respective wire connecting portions  32   a  and  33   a  of the terminals  12  and  13  which are then bent upward by typically forcing the solder portions using a dedicated jig or tool, without damaging extended portions of the wire. 
         [0006]    With the recent trend of miniaturization of the electromagnetic relay devices, it becomes difficult for the bending tool to force only small soldered portions of the terminals and there is an increased likelihood that the bending jig will force and damage and, as a result, break the extended portions of the wire at the bending of the coil 
       SUMMARY 
       [0007]    Accordingly, one or more embodiments of the present invention is to provide a coil terminal which prevents the breaking likelihood of the extended portions of the wire at the bending of the coil terminals by the bending jig and to provide an electromagnetic relay incorporating the coil terminals. 
         [0008]    A coil terminal according to one or more embodiments of the invention comprises a winding section around which is configured so that an end of coiled wire is wound around the winding section and then the winding section is bent relative to a remaining section of the coil terminal; the winding section having a pair of, proximal and distal wire engagement portions spaced away from each other in a longitudinal direction of the winding section, the wire end being extended in a region ranging from the proximal wire engagement portion to the distal wire engagement portions without being wound around the region. 
         [0009]    With this arrangement of the coil terminal, at the winding of the wire end around the winding section, it is extended between the proximal and distal wire engagement portions without being wound around the region ranging between the proximal and distal wire engagement portions. This allows that the bending jig to force and bend the region without making contact with the extended wire in the region, which prevents the wire from being damaged or broken in the region. 
         [0010]    According to one or more embodiments of the invention, a part of the wire end is wound around a distal end region positioned on and then soldered to a distal side of the distal wire engagement portion. 
         [0011]    Accordingly, the wire wound around the distal end region is covered by the solder, preventing the bending jig from making contact with the wire wound around the region, which in turn prevents the wire in that region from being damaged or broken by the bending jig even for a small coil terminal. 
         [0012]    According to one or more embodiments of the invention, each of the proximal and distal wire engagement portions may be a convex configuration. 
         [0013]    Accordingly, a greater freedom is provided for the designing of the coil terminal. 
         [0014]    According to one or more embodiments of the invention, one of the proximal and distal wire engagement portions may be a convex configuration and the other of the proximal and distal wire engagement portions may be a concave configuration. 
         [0015]    Accordingly, a greater freedom is provided for the designing of the coil terminal. 
         [0016]    According to one or more embodiments of the invention, each of the proximal and distal wire engagement portions may be a concave configuration. 
         [0017]    Accordingly, a greater freedom is provided for the designing of the coil terminal. 
         [0018]    According to one or more embodiments of the invention, the proximal and distal wire engagement portions are angularly offset from each other about a longitudinal axis of the winding section. 
         [0019]    Accordingly, a greater freedom is provided for the designing of the coil terminal. 
         [0020]    According to one or more embodiments of the invention, the proximal and distal wire engagement portions are positioned on opposite sides of a longitudinal axis of the winding section. 
         [0021]    Accordingly, a greater freedom is provided for the designing of the coil terminal. 
         [0022]    According to one or more embodiments of the invention, an electromagnetic relay comprises any one of the coil terminals. 
         [0023]    Accordingly, the electromagnetic relay is provided which is capable of preventing the wire from being damaged or broken at the bending of the winding section by means of the bending jig or tool. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]      FIG. 1  is a top plan view of a coil unit in which coil terminals according to a first embodiment of the invention are assembled, showing the coil terminals before they are bent; 
           [0025]      FIG. 2  is a cross sectional view of the coil unit taken along lines II-II in  FIG. 1 ; 
           [0026]      FIG. 3  is a side elevational view of the coil unit, showing coil terminals before they are bent; 
           [0027]      FIG. 4  is a perspective view showing the coil terminal assembled in the electromagnetic relay in  FIG. 1 ; 
           [0028]      FIG. 5  is a schematic view showing that the coil terminal is being forced and bent by a bending jig or tool; 
           [0029]      FIG. 6  is a schematic view showing forces applied to the coil terminal; 
           [0030]      FIG. 7  is a schematic view showing a coil terminal according to a second embodiment of the invention; 
           [0031]      FIG. 8  is a schematic view showing a coil terminal according to a third embodiment of the invention; 
           [0032]      FIG. 9  is a schematic view showing a coil terminal according to a fourth embodiment of the invention; 
           [0033]      FIG. 10  is a schematic view showing a coil terminal according to a fifth embodiment of the invention; 
           [0034]      FIG. 11  is a schematic view showing a coil terminal according to a sixth embodiment of the invention; 
           [0035]      FIG. 12  is a schematic view showing a coil terminal according to a seventh embodiment of the invention; 
           [0036]      FIG. 13  is a schematic view showing a coil terminal according to an eighth embodiment of the invention; and 
           [0037]      FIG. 14  is a schematic view showing a coil terminal according to a ninth embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0038]    With reference to the accompanying drawings, embodiments of the invention will be described below. In embodiments of the invention, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to one of ordinary skill in the art that the invention may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid obscuring the invention. 
         [0039]    In the following descriptions, directional terminology such as “upper”, “lower”, etc., is used with reference to the orientation of the drawing(s) being described, it is used for purposes of better understanding of the invention and is in no way limiting the technical scope of the invention. 
       First Embodiment 
       [0040]    As shown in  FIGS. 1 to 3 , a coil unit, generally indicated by reference numeral  1 , in which the coil terminals according to a first embodiment of the invention are incorporated, has a spool  10  made of a cylindrical portion  10   b  and a pair of flanges  10   a  integrally mounted on opposite ends of the cylindrical portion  10   b , and a coil  20  formed by winding a wire  20   a  around the cylindrical portion  10   b  of the spool  10 . The coil unit  1  further has a pair of coil terminals  30  mounted on opposite sides of one flange  10   a.    
         [0041]    As shown in  FIG. 2 , the spool  10  has a through-hole  11  formed at substantially a center thereof and inside the cylindrical portion  10   b . One of the flanges  10   a  of the spool  10  has a pair of grooves  13  in each of which a coil terminal  30  is press-fitted. 
         [0042]    The opposite ends  21  of the wire  20   a  of the coil  20 , wound around the spool  10 , are extended out of the coil  20  and tangled and wound around respective coil terminals  30 . For convenience, the extended ends  21  of the wire  20   a  are omitted from  FIGS. 1 and 3 . 
         [0043]    As shown in  FIG. 4 , the coil terminal  30  has a primary section  31 , a terminal section  32 , and a winding section  33  formed integrally therewith. 
         [0044]    The primary section  31  is L-shaped and has a press-fitting projection  34  for preventing the coil terminal  30  press-fitted in the groove  13  of the spool  10  from dropping therefrom. 
         [0045]    The terminal section  32 , which has a rectangular cross-section and is extended downward and linearly from the primary section  31 , is press-fitted in the terminal groove not shown defined in the electromagnetic relay at the assembling of the coil unit into the electromagnetic relay. 
         [0046]    The winding section  33 , which has a rectangular cross-section and is extended laterally from the primary section  31 , has a double-angled, proximal section  33   a  made of a pair of vertically shifted horizontal portions and a vertical portion connecting between the horizontal portions, and a straight portion  33   b  extending from the proximal section  33   a . The proximal section  33   a  has a thinned portion  37 , provided adjacent the primary section  31 , where it is bent relative to the primary portion as shown in  FIG. 1 . Also, the straight portion  33   b  has upper and lower projections  35  and  36  defined on opposite sides with respect to the longitudinal axis of the winding section  33 , i.e., integrally on the upper and lower surfaces thereof, respectively. The upper and lower projections  35  and  36  are laterally shifted from each other so that they constitute a pair of spaced wire engagement portions. 
         [0047]    Next, discussions will be made to an assembling of the coil unit. 
         [0048]    The coil terminals  30  are each press-fitted in the grooves  13  of the spool  10  so that they oppose to each other. 
         [0049]    Then, the ends of the wire  20   a  extended from the coil  20  are wound and tangled around the winding sections of the coil terminals  30 . 
         [0050]    In this process, as shown in  FIG. 5 , each extended end  21  of the wire  20   a  is wound and tangled around a region of the proximal section  33   a , positioned on the proximal side of the upper projection  35 . Next, the wire end  21  is extended distally along the side surface of the winding section  33  from the proximal end engaging surface  35   a  of the upper projection  35  to the distal end engaging surface  36   a  of the lower projection  36  and then wound and tangled around a distal region of the winding section  33 , positioned adjacent and on the distal side of the lower projection  36 . 
         [0051]    Subsequently, the portion of the wire  20   a  wound around the distal region of the winding section  33  is soldered to the coil terminal  30 . For example, the soldering covers a region ranging from the distal end engaging surface  36   a  of the lower projection  36  to the distal tip end of the winding section  33 . 
         [0052]    Next, as shown in  FIG. 1 , the winding section  33  is bent by a bending jig  50  from a position illustrated in solid lines to a position illustrated in dashed lines (illustrated in solid lines in  FIG. 3 ). 
         [0053]    Specifically, as shown in  FIG. 5 , in this bending the winding section  33  is forced by the jig  50  at the region between the upper and lower projections  35  and  36  and at the distal region covered by the solder  40 . 
         [0054]    As such, in the process of winding the wire end  21  around the winding section  33 , the wire end  21  is extended from the proximal end engaging surface  35   a  of the upper projection  35  to the distal end engaging surface  36   a  of the lower projection  36 , without being wound therearound. This prevents the wire portion extending between the projections  35  and  36  from being forced by the jig  50  and, as a result, from breaking during the bending of the winding section  33 . 
         [0055]    Also, the soldering covers the portion of the wire  20   a  wound around the region ranging from the distal end engaging surface  36   a  of the lower projection  36  to the distal end of the winding section  33 , which allows the jig to force and bend the winding section  33  without making any contact with the wire. 
         [0056]    As described above, according to the first embodiment, a breaking of the wire  20   a  is reliably prevented because the jig  50  forces the winding section  33  without making any contact with the wire  20   a.    
       Other Embodiments 
       [0057]    Although the paired wire engagement portions are constituted by the upper and lower projections  35  and  36  in the first embodiment, they may be formed in different manner. For example, in the second embodiment shown in  FIG. 7  the wire engagement portions are provided by forming a concave portion  105  and a convex projection  106  on the opposite, respective surfaces of the straight portion  103 . Alternately, in the third embodiment shown in  FIG. 8  the wire engagement portions are provided by forming a convex portion  115  and a concave portion  116  on the opposite respective surfaces of the straight portion  113 . Alternatively, in the fourth embodiment shown in  FIG. 9  the wire engagement portions are provided by forming convex portions  125  and  126  on the opposite respective surfaces of the straight portion  123 . As described above, the engagement portions may be convex portions or concave portions, or they may be convex and concave portions. 
         [0058]    Although in the first embodiment the engagement portions, i.e., the projections  35  and  36 , are formed on opposite sides of the longitudinal axis of the winding section  33 , i.e, upper and lower surfaces of the winding section  33 , they may be provided in different manner. For example, in the fifth embodiment shown in in  FIG. 10  the engagement portions are provided by forming projections  135  and  136  on the neighborhood surfaces of the straight portion  133   b  of the winding section  133  so that they extend in respective, orthogonal directions relative to each other. Alternatively, in the sixth embodiment shown in  FIG. 11  the wire engagement portions are provided by forming a concave portion  145  and a convex portion  146  on the neighboring respective surfaces of the straight portion  143   b  of the winding section  143 . Alternatively, in the seventh embodiment shown in  FIG. 12  the wire engagement portions are provided by forming concave portions  155  and  156  on the neighboring respective surfaces of the straight portion  153   b  of the winding section  153 . As described above, the engagement portions may be provided on the angularly shifted positions around the longitudinal axis of the winding section. 
         [0059]    Also, in the eighth embodiment shown in  FIG. 13  the engagement portions are provided by forming projections  165  and  166 , on the straight portion  163   b  of the winding section  163 , each having substantially triangle cross sections aligned on the longitudinal axis of winding section  153 . Alternatively, in the ninth embodiment shown in  FIG. 14  the engagement portions are provided by forming substantially triangle cross-section projections  175  and  176  so that they are oriented in different, orthogonal directions. 
         [0060]    As described above, the paired engagement portions may take any configuration and position provided that the wire ends  21  can be engaged thereon and extended therebetween. 
         [0061]    The distance between the paired engagement portions can be determined in accordance with the design requirements of the electromagnetic relay including the coil terminals provided that a space is secured for the winding portion to be forced without making any contact between the bending jig and the wire. 
         [0062]    One or more embodiments of the present invention may be applied to any coil terminal with a winding section and a pair of wire engagement portions formed thereon. Also, the coil terminal may be modified or redesigned in accordance with the design requirements of the electromagnetic relay including the coil terminal. 
         [0063]    The coil terminals described in the first to ninth embodiments are not limited to a terminal for making an electrical connection with another element such as a relay terminal for making an electrical connection with a component provided in the same device. 
         [0064]    Each of the structural components of the coil terminals in the first to ninth embodiment may be replaced with another, similar component in a different embodiment or may be added to a different embodiment. 
         [0065]    Each of the coil terminals in the first to ninth embodiments may be incorporated in any electromagnetic relay. 
         [0066]    The coil terminal according to one or more embodiments of the invention may be incorporated not only in the above-described coil unit but also in another coil unit. Also, the coil terminal according to one or more embodiments of the invention may be incorporated in any electromagnetic relay. 
         [0067]    While the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims. 
       PARTS LIST 
       [0000]    
       
           10 : spool 
           10   a : flange 
           11 : through-hole 
           20 : coil 
           21 : wire end 
           30 : coil terminal 
           32 : terminal section 
           33 ,  103 ,  113 ,  123 ,  133 ,  143 ,  153 ,  163 ,  173 : winding section 
           33   a : proximal section 
           33   b ,  103   b ,  113   b ,  123   b ,  133   b ,  143   b ,  153   b ,  163   b ,  173   b : straight portion 
           34 : press-fitting projection 
           35 ,  115 ,  135 ,  136 ,  146 ,  165 ,  166 ,  175 ,  176 : projection 
           35   a : end surface 
           36 ,  106 : projection 
           36   a : end surface 
           37 : thinned portion 
           40 : solder 
           50 : jig 
           105 ,  116 ,  125 ,  126 ,  145 ,  155 ,  156 : concave portion