Patent Publication Number: US-8991044-B2

Title: Method for inserting a wire into a contact pin with a wire insertion tool

Description:
This application is a divisional application of U.S. patent application Ser. No. 13/372,664, now U.S. Pat. No. 8,578,590, filed Feb. 14, 2012. 
    
    
     CROSS-REFERENCE 
     This patent application claims a priority on convention based on Japanese Patent Application No. JP 2011-084307. The disclosure thereof is incorporated herein by reference. 
     TECHNICAL FIELD 
     The present invention is related to a tool for inserting a wire into a contact pin and a method of inserting a wire in a contact pin. 
     BACKGROUND ART 
     An example of a technique for inserting a wire into a tubular object will be described below. 
     Patent Literature 1 discloses a sleeve wire insertion guide tool which is used for a new construction or a repair construction of a transmission and distribution wire. A termination treatment of a cut wire is carried out in the new construction works or the repair construction of the transmission and distribution wire. That is, the wire terminals formed by cutting the wire in the construction are inserted in a sleeve to oppose to each other, and are connected by a crimping connection of them and the sleeve by using the tool. The sleeve wire insertion guide tool is provided with a pair of division blocks obtained through division along into the direction of an axis line, and a spring with a wide width which biases the division blocks in the direction opposing to each other. The division blocks form an opening section of a cone shape, and a circular tube insertion section which has the inner diameter and the outer diameter which are substantially identical with those of the sleeve and which is communicated with the opening section. The spring is fixed to the insertion section. An operator expands a space between the division blocks with the hands against the biasing force by the spring and brings the end of the insertion section into contact to the sleeve. Then, the hands are released and the division blocks sandwiches the sleeve with the spring, to couple the insertion section and the sleeve. In this way, the sleeve wire insertion guide tool is attached to each of the ends of the sleeve. The sleeve with the sleeve wire insertion guide tools on the both ends is arranged between the wire terminals to be connected, and the wire terminals are inserted into the sleeve by moving in the direction opposing to each other. At this time, because each of the wire terminals is inserted into the sleeve along the inner wall of a cone-shaped opening of the sleeve wire insertion guide tool, the wire terminals are inserted in the sleeve in the alignment with the center of the sleeve. Then, the sleeve wire insertion guide tools are removed from the both ends of the sleeve and the wire terminals and the sleeve are crimped. 
     Patent Literature 2 discloses an insertion jig which is attached to each end of a sleeve to facilitate the insertion of a wire into the sleeve. The insertion jig is provided with a jig body and a hinge. The jig body consists of two longitudinal division parts. Each of the longitudinal division parts is provided with a half conical section and a half tube section provided to unify with the half conical section. The hinge connects the two longitudinal division parts to be openable and closable. The half conical sections of the two longitudinal division parts form a conical opening to facilitate the insertion of the wire. The two longitudinal division parts are closed such that the half tube sections of the two longitudinal division parts engage with the external circumferential surface of the sleeve, and the half tube sections are fixed on the sleeve with an adhesive tape. After inserting the wire in the sleeve, the adhesive tape is cut to remove the insertion jig from the sleeve. 
     The inventor of the present invention recognizes as follows. In the sleeve wire insertion guide tool disclosed in Patent Literature 1, there is a possibility that the spring is deformed through the repetitive use so that the structure formed from the division blocks is changed from an initial desired structure. In the insertion jig disclosed in Patent Literature 2, the shape precision of the structure formed from the two longitudinal division parts is low because of a looseness of the hinge. Therefore, it is difficult to apply the sleeve wire insertion guide tool of Patent Literature 1 and the insertion jig of Patent Literature 2 to a process of inserting a fine wire into a contact pin with a minimal diameter. Moreover, it is not possible to carry out a wire insertion process by only the sleeve wire insertion guide tool of Patent Literature 1 or the insertion jig of Patent Literature 2, and it is necessary to combine with another tool and instruments for the wire insertion. 
     CITATION LIST 
     [Patent Literature 1]: Japanese Registered Utility Model No. 2,511,820 
     [Patent Literature 2] JP H08-250257A 
     SUMMARY OF THE INVENTION 
     The purpose of the present invention is to provide a wire insertion tool and a method of inserting a wire, which are suitable for insertion of the fine wire into a contact pin with a minimal diameter. 
     The wire insertion tool by the present invention includes: a first division block having a first wire insertion guide ditch forming plane where a first wire insertion guide ditch has been formed; a second division block having a second wire insertion guide ditch forming plane where a second wire insertion guide ditch has been formed; and a division block positioning guide. When the first division block and the second division block form a coupling unit by fitting the first wire insertion guide ditch forming plane and the second wire insertion guide ditch forming plane, the first wire insertion guide ditch and the second wire insertion guide ditch form a wire insertion guide hole to pass through the coupling unit from one side thereof to the other side thereof. The division block positioning guide guides one of the first division block and the second division block linearly to the other such that the first wire insertion guide ditch forming plane and the second wire insertion guide ditch forming plane approach to each other or separate from each other. 
     The division block positioning guide includes two positioning pins which are fixed on one of the first division block and the second division block. The two positioning pins may be arranged in positioning pin arrangement holes formed in the other of the first division block and the second division block, respectively. 
     A first wire drawing ditch which is different from the first wire insertion guide ditch is formed on the first wire insertion guide ditch forming plane. A second wire drawing ditch which is different from the second wire insertion guide ditch is formed on the second wire insertion guide ditch forming plane. The first wire drawing ditch and the second wire drawing ditch form a wire drawing hole to pass through the coupling unit from one side thereof to the other side thereof, when the first division block and the second division block form the coupling unit by fitting the first wire insertion guide ditch forming plane and the second wire insertion guide ditch forming plane. 
     The wire insertion tool further includes: a spring configured to bias the first division block and the second division block so as to separate the first wire insertion guide ditch forming plane and the second wire insertion guide ditch forming plane. 
     The wire insertion tool further includes: a cam clamp configured to hold the first division block and the second division block in the condition that the first wire insertion guide ditch forming plane and the second wire insertion guide ditch forming plane are fit with each other. 
     In a wire inserting method, a wire insertion tool includes: a first division block having a first wire insertion guide ditch forming plane on which a first wire insertion guide ditch has been formed; a second division block having a second wire insertion guide ditch forming plane on which a second wire insertion guide ditch has been formed; and a division block positioning guide configured to guide one of the first division block and the second division block linearly to the other such that the first wire insertion guide ditch forming plane and the second wire insertion guide ditch forming plane approach to each other or separate from each other. The wire inserting method includes: forming a coupling unit from the first division block and the second division block such that the first wire insertion guide ditch forming plane and the second wire insertion guide ditch forming plane approach to each other or separate from each other; inserting a contact pin from the one side into the wire insertion guide hole which is formed from the first wire insertion guide ditch and the second wire insertion guide ditch to pass through the coupling unit from the one side to the other side; inserting a wire into the contact pin from the other side through the wire insertion guide hole; separating the first division block and the second division block such that a space is formed between the first wire insertion guide ditch forming plane and the second wire insertion guide ditch forming plane; and drawing out the wire together with the contact pin from the space between the first division block and the second division block. 
     A first wire drawing ditch which is different from the first wire insertion guide ditch is formed on the first wire insertion guide ditch forming plane, and a second wire drawing ditch which is different from the second wire insertion guide ditch is formed on the second wire insertion guide ditch forming plane. The first wire drawing ditch and the second wire drawing ditch forms a wire drawing hole to pass through the coupling unit from one side thereof to the other side thereof, in forming a coupling unit. The wire inserting method further includes: moving the wire and the contact pin from a position corresponding to the first wire insertion guide ditch and the second wire insertion guide ditch to a position corresponding to the first wire drawing ditch and the second wire drawing ditch, between the separating and the drawing. 
     The wire insertion tool further includes a spring configured to bias the first division block and the second division block. The separating includes: separating the first division block and the second division block by the spring. 
     The wire insertion tool further includes a cam clamp configured to hold the first division block and the second division block in the condition that the first wire insertion guide ditch forming plane and the second wire insertion guide ditch forming plane are fit with each other. The separating includes: separating the first division block and the second division block by operating the cam clamp. 
     The forming a coupling unit includes: pushing the first division block and the second division block each other such that the first wire insertion guide ditch forming plane and the second wire insertion guide ditch forming plane are fit with each other. Each of the inserting a contact pin and the inserting a wire includes: holding the first division block and the second division block in the condition that the first wire insertion guide ditch forming plane and the second wire insertion guide ditch forming plane are fit with each other. The separating includes: relaxing force to hold the first division block and the second division block in the condition that the first wire insertion guide ditch forming plane and the second wire insertion guide ditch forming plane are fit with each other. 
     According to the present invention, the wire insertion tool and a wire inserting method are provided, which are suitable for the insertion of a fine wire into a contact pin with a minimal diameter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a front view of a wire insertion tool according to a first embodiment of the present invention; 
         FIG. 1B  is a side view of the wire insertion tool according to the first embodiment; 
         FIG. 1C  is a partial expanded view of  FIG. 1B ; 
         FIG. 2  is a flow chart of a wire inserting method according to the first embodiment; and 
         FIG. 3  is a front view of the wire insertion tool according to a second embodiment of the present invention. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Hereinafter, a wire insertion tool and a method of inserting a wire according to the present invention will be described in detail with reference to the attached drawings. 
     First Embodiment 
     Referring to  FIG. 1A , the wire insertion tool  1  according to a first embodiment of the present invention is provided with an upper-side division block  10 , a lower-side division block  20 , two positioning guides  30 , two springs  40  and a cam clamp  50 . 
     The upper-side division block  10  is formed in a block. The upper-side division block  10  is provided with a wire insertion guide ditch forming plane  11 . The wire insertion guide ditch  12  and the wire drawing ditch  13  are formed in the wire insertion guide ditch forming plane  11 . The wire insertion guide ditch  12  and the wire drawing ditch  13  are apart from each other. The positioning guide  30  is fixed in the upper-side division block  10 . The positioning guide  30  protrudes perpendicularly from the wire insertion guide ditch forming plane  11 . For example, the positioning guide  30  is a positioning pin. The cam clamp axis arrangement hole  15  is formed to pass through the upper-side division block  10 . The axial direction of the cam clamp axis arrangement hole  15  is perpendicular to the wire insertion guide ditch forming plane  11 . One end of the cam clamp axis arrangement hole  15  is open to the wire insertion guide ditch forming plane  11 . 
     The lower-side division block  20  is formed in a block. The lower-side division block  20  has a wire insertion guide ditch forming plane  21 . The wire insertion guide ditch  22  and the wire drawing ditch  23  are formed in the wire insertion guide ditch forming plane  21 . The wire insertion guide ditch  22  and the wire drawing ditch  23  are apart from each other. The two positioning guide arrangement holes  25  are formed in the lower-side division block  20 . The axial direction of the positioning guide arrangement hole  25  is perpendicular to the wire insertion guide ditch forming plane  21 . One end of the positioning guide arrangement hole  25  is open to the wire insertion guide ditch forming plane  21 . The positioning guide arrangement hole  25  may or may not pass through the lower-side division block  20 . 
     The two positioning guides  30  are arranged in the two positioning guide arrangement holes  25 , respectively. The positioning guide  30  guides the lower-side division block  20  linearly to the upper-side division block  10  so that the wire insertion guide ditch forming plane  11  and the second wire insertion guide ditch forming plane  12  approach to each other or separate from each other in an opposing condition of them. That is, the positioning guide  30  defines the relative positions of the upper-side division block  10  and the lower-side division block  20  by limiting a relative displacement in a plane parallel to the wire insertion guide ditch forming planes  11  and  21  of the upper-side division block  10  and the lower-side division block  20 . It should be noted that the positioning guide  30  may be provided to guide the upper-side division block  10  linearly to the lower-side division block  20 . The spring  40  is provided to bias the upper-side division block  10  and the lower-side division block to separate the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21 . For example, the spring  40  is a coil spring which is arranged around the positioning guide  30 . It should be noted that the numbers of positioning guides  30 , positioning guide arrangement holes  25  and springs  40  may be equal to or more than 3. 
     The cam clamp  50  is configured to allow the upper-side division block  10  and the lower-side division block  20  to be held in the condition (surface contact condition) that the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21  are fit. The cam clamp  50  is provided with a shaft  51 , a driver  53  and a follower  54 . The shaft  51  is arranged in the cam clamp axis arrangement hole  15  such that the ends of the shaft  51  protrude from opposite sides of the upper-side division block  10 . One of the ends of the shaft  51  is fixed on the lower-side division block  20  and the other of the ends of the shaft  51  is provided for a rotation axis  52 . The driver  53  is provided with a cam part  53   a  which is rotated around the rotation axis  52  and a lever part  53   b  which is fixed on the cam part  53   a . In  FIG. 1A , an upper portion of the cam part  53   a  is thin and the lower portion of the cam part  53   a  is thick. Therefore, when the driver  53  is driven to an upper direction, the upper-side division block  10  and the lower-side division block  20  are set to be not in the fitting condition. The follower  54  is provided between the cam part  53   a  and the upper-side division block  10  to be removable along the shaft  51  and engages the cam part  53   a  and the upper-side division block  10 . 
     When a coupling unit  2  is formed from the upper-side division block  10  and the lower-side division block  20  by fitting the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21 , the wire insertion guide ditch  12  and the wire insertion guide ditch  22  form the wire insertion guide hole  5 , and the wire drawing ditch  13  and the wire drawing ditch  23  form the wire drawing hole  6 . 
     It should be noted that the wire insertion guide hole  5  and the wire drawing hole  6  may be arranged between the two positioning guides  30  and also may be arranged outside the two positioning guides  30 . 
     Referring to  FIG. 1B , the wire insertion guide hole  5  passes through the coupling unit  2  from one side  3  to the other side  4 . In the condition that the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21  are fit, the wire insertion guide ditch forming plane  11 , the wire insertion guide ditch forming plane  21  and a centerline of the wire insertion guide hole  5  are arranged on a same plane. The wire insertion guide hole  5  is provided with a circular tube section  5   a  open to the one side  3  and a taper section  5   b  which is formed to gradually narrows from the other side  4  toward the circular tube section  5   a . Although not shown in  FIG. 1B , the wire drawing hole  6  also passes through the coupling unit  2  from one side  3  to the other side  4 . It should be noted that the wire drawing hole  6  is formed to be sufficiently wider than the circular tube section  5   a.    
     Referring to  FIG. 1C , the inner diameter of the circular tube section  5   a  is shown as D 1  and the inner diameter of the narrowest part of the taper section  5   b  is shown as D 2 . 
     Referring to  FIG. 2 , a method of inserting a wire by using the wire insertion tool  1  according to the present embodiment will be described. The method of inserting the wire is provided with a step S 1  to a step S 6 . 
     At a step S 1 , an operator pushes the upper-side division block  10  onto the lower-side division block  20  by having the lever part  53   b  with the hand and rotating the cam clamp  50  downwardly, and couples the upper-side division block  10  and the lower-side division block  20  to fit the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21 . In detail, the follower  54  and the upper-side division block  10  are moved in the direction toward the lower-side division block  20  through the rotation of the driver  53 , and the upper-side division block  10  is pushed to the lower-side division block  20 . Thus, the coupling unit  2  is formed. By fitting the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21 , the wire insertion guide ditch  12  and the wire insertion guide ditch  22  form the wire insertion guide hole  5 , and the wire drawing ditch  13  and the wire drawing ditch  23  form the wire drawing hole  6 . 
     Until separating the upper-side division block  10  and the lower-side division block  20  in the step S 4 , the upper-side division block  10  and the lower-side division block  20  are held by the cam clamp  50  in the condition that the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21  are fit. Therefore, the operator can use both hands freely at the steps S 2  and S 3 . 
     At the step S 2 , the operator inserts a contact pin (not shown) from the one side  3  of the coupling unit  2  into the circular tube section  5   a  of the wire insertion guide hole  5 . 
     At the step S 3 , the operator inserts a wire (not shown) into the contact pin from the other side  4  of the coupling unit  2  through the taper section  5   b  of the wire insertion guide hole  5  to attach the contact pin to the wire. At this time, because the wire is guided by the surfaces of the wire insertion guide ditches  12  and  22  which form the taper section  5   b , the wire can be quickly and surely inserted into the contact pin. It should be noted that when the inner diameter D 2  of the narrowest part of the taper section  5   b  is smaller than the inner diameter of the contact pin, it is prevented that the tip of the wire is caught on the end of the contact pin. Therefore, it is desirable that the inner diameter D 2  of the narrowest part of the taper section  5   b  is smaller than the inner diameter D 1  of the circular tube section  5   a.    
     At the step S 4 , the operator separates the upper-side division block  10  and the lower-side division block  20  by having the lever part  53   b  with the hand and rotating the cam clamp  50  upwardly. In detail, because movable ranges of the follower  54  and the upper-side division block  10  are extended in a direction away from the lower-side division block  20  through the rotation of the driver  53 , the condition is cancelled in which the wire insertion guide ditch forming plane  11  of the upper-side division block  10  and the wire insertion guide ditch forming plane  21  and the lower-side division block  20  are fit. As a result, the springs  40  separate the upper-side division block  10  and the lower-side division block  20  such that a space is formed between the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21 . Because the upper-side division block  10  and the lower-side division block  20  are separated by the springs  40 , the workability is excellent. 
     At the step S 5 , the operator moves the contact pin and the wire inserted therein from a position corresponding to the wire insertion guide ditch  12  and the wire insertion guide ditch  22  to a position corresponding to the wire drawing ditch  13  and the wire drawing ditch  23  through a space between the upper-side division block  10  and the lower-side division block  20 . 
     At the step S 6 , the operator pulls out the contact pin and the wire inserted therein from the space between the upper-side division block  10  and the lower-side division block  20 . By pulling out the wire from the position corresponding to the wire drawing ditch  13  and the wire drawing ditch  23 , a sufficient distance can be secured between the contact pin and a set of the upper-side division block  10  and the lower-side division block  20 , compared with a case to pull the wire from the position corresponding to the wire insertion guide ditch  12  and the wire insertion guide ditch  22 . Therefore, when pulling out the wire, it is prevented that the contact pin contacts the upper-side division block  10  or the lower-side division block  20  so that the contact pin comes off from the wire. By providing the wire drawing ditch  13  and the wire drawing ditch  23  for the upper-side division block  10  and the lower-side division block  20 , respectively, it becomes easy to pull the wire out of a space between the upper-side division block  10  and the lower-side division block  20 , even when the space between the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21  is small. When the space between the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21  may be small, the wire insertion tool  1  can be made small in size. 
     After pulling out the wire, the operator crimps the wire and the contact pin. 
     According to the present embodiment, because the positioning guide  30  guides one of the upper-side division block  10  and the lower-side division block  20  linearly to the other, the shape of the wire insertion guide hole  5  to be formed at the step S 1  has high precision. In other words, center lines are prevented from being displaced between the contact pin inserted in the circular tube section  5   a  of the wire insertion guide hole  5  and the taper section  5   b  in the wire insertion guide hole  5 . Therefore, according to the wire insertion tool and the method of inserting the wire according to the present embodiment, the work quality and the work-ability are excellent even when inserting a thin wire in a contact pin with a minimal diameter. 
     Moreover, because the coupling and separation of the upper-side division block  10  and the lower-side division block  20  can be carried out by a simple rotation of the cam clamp  50 , the wire insertion tool  1  according to the present embodiment is excellent in work-ability. 
     Second Embodiment 
     Referring to  FIG. 3 , the wire insertion tool  1  according to a second embodiment of the present invention will be described. The wire insertion tool  1  according to the present embodiment is provided with the upper-side division block  10 , the lower-side division block  20 , the positioning guide  30  and the spring  40 , like the wire insertion tool  1  according to the first embodiment, but it is not provided with the cam clamp  50 . Moreover, the wire insertion tool  1  according to the present embodiment is provided with a knob  60  and a stopper  70 . For example, the knob  60  is a picked knob fixed on the upper-side division block  10 . The stopper  70  limits and prevents that the upper-side division block  10  and the lower-side division block  20  are separated beyond a predetermined distance. For example, the stopper  70  is a shoulder bolt fixed on the lower-side division block  20  so as to stop the upper-side division block  10  when the upper-side division block  10  is separated from the lower-side division block  20  by the predetermined distance. 
     The method of inserting a wire by using the wire insertion tool  1  according to the present embodiment is provided with the step S 1  to the step S 6 , like the method of inserting a wire by using the wire insertion tool  1  according to the first embodiment, but the detail of the step S 1  to the step S 4  are different from those in the first embodiment. 
     At the step S 1 , the operator forms the coupling unit from the upper-side division block  10  and the lower-side division block  20  by contacting the knob  60  with the hand and pushing the upper-side division block  10  to the lower-side division block  20 , such that the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21  are fit. Thus, the coupling unit  2  is formed. By fitting the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21 , the wire insertion guide ditch  12  and the wire insertion guide ditch  22  form the wire insertion guide hole  5 , and the wire drawing ditch  13  and the wire drawing ditch  23  form the wire drawing hole  6 . 
     Until separating the upper-side division block  10  and the lower-side division block  20  in the step S 4 , the operator holds the upper-side division block  10  and the lower-side division block  20  in the condition that the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21  are fit. 
     At the step S 2 , while holding the upper-side division block  10  and the lower-side division block  20  in the condition that the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21  are fit, the operator inserts a contact pin (not shown) from the one side  3  of the coupling unit  2  into the circular tube section  5   a  of the wire insertion guide hole  5 . 
     At the step S 3 , while holding the upper-side division block  10  and the lower-side division block  20  in the condition that the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21  are fit, the operator inserts a wire (not shown) into the contact pin from the other side  4  of the coupling unit  2  through the taper section  5   b  of the wire insertion guide hole  5  and attaches the contact pin to the wire. 
     At the step S 4 , the operator separates the upper-side division block  10  and the lower-side division block  20  by relaxing the force applied to hold the upper-side division block  10  and the lower-side division block  20  in the condition that the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21  are fit. Here, the case that the operator relaxes the force includes a case that the operator separates his hand from the knob  60  and a case that the operator does not separate. In detail, by relaxing the force, the spring  40  separates the upper-side division block  10  from the lower-side division block  20  until the upper-side division block  10  is stopped by the stopper  70 . As a result, the upper-side division block  10  and the lower-side division block  20  are separated for a space to be formed between the wire insertion guide ditch forming plane  11  and the wire insertion guide ditch forming plane  21 . 
     The steps S 5  and S 6  are the same as those in the first embodiment. 
     While it takes a time until the operator acclimates himself to the wire insertion tool  1  according to the present embodiment, the operation speed becomes faster when the acclimated operator uses the wire insertion tool  1  according to the present embodiment, compared with a case of using the wire insertion tool  1  according to the first embodiment. 
     In the above, the wire insertion tool and the method of inserting a wire according to the present invention have been described with reference to the embodiments. However, the wire insertion tool and the method of inserting the wire according to the present invention are not limited to the above embodiments. For example, the wire drawing ditches  12  and  22  may not be provided. The wire may be drawn out of the position corresponding to the wire insertion guide ditch  12  and the wire insertion guide ditch  22  at the step S 6  without executing the step S 5 . Also, the operator may separate the upper-side division block  10  and the lower-side division block  20  with the hand without providing the springs  40 .