Patent Publication Number: US-6901657-B2

Title: Wiring harness production apparatus

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a production apparatus for a wiring harness arranged in a mobile unit such as a motor vehicle. 
   2. Related Art 
   A motor vehicle has a wiring harness for supplying a power to electrical appliances such as various lamps and motors from a battery. A conventional wiring harness includes a plurality of electrical cables, a plurality of terminals each fitted to an end of each electrical cable, connector housings accommodating the terminals, etc. 
   An ordinary or high grade car has an increasing number of on-vehicle electronics components, which requires hundreds to thousands of electrical cables. Thus, a wiring harness for such a car tends to have an increasing number of electrical cables. 
   For assembling the wiring harness, a plurality of sub-wiring harnesses which has a plurality of electrical cables and connectors, are assembled. Thereafter, these sub-harnesses are combined with one another to complete the wiring harness. Thus, the wiring harness production line has a plurality of sub-harness assembling lines and a wiring harness assembling line. 
   For assembling the sub-harness, each sub-harness assembling line press-fits or crimps a terminal to each end of each one of plural electrical cables. If required, the electrical cables are directly connected to one another by crimping or the like. Thereafter, these terminals are received in terminal accommodation chambers of connector housings to assemble the sub-harness. 
   The wiring harness assembling line combines the sub-harnesses with one another to obtain the wiring harness. The wiring harness assembling line has used, for example, a plurality of wiring boards. The wiring board travels on a circulation course on a floor of a factory and has clips for bundling the electrical cables. On the wiring board, the electrical cables are crimped at predetermined points to arrange the electrical cables and the sub-harnesses to obtain the wiring harness. 
   However, the conventional wiring harness production line has the plurality of sub-harness production lines which are independent of each other. Thus, each sub-harness production line has a specified time for producing a single sub-harness, and the specified time is different from that of another sub-harness production line. 
   Some electrical cables of the sub-harnesses are directly connected to each other. Such electrical cables of the sub-harnesses should be once transferred from an automatic assembling line having a known crimping machine to a known joint crimping machine or a conventional resistance welding machine. 
   The direct connection of the electrical cables varies a time requested for assembling the sub-wiring harnesses. Thus, the sub-harness assembling lines vary from each other in their assembling times. 
   The wiring harness assembling line needs to stock an amount of the sub-harness. The wiring harness assembling line uses the stocked sub-harnesses to complete the wiring harness, so that the wiring harness assembling line receives an appropriate number of the sub-harnesses in consideration of the work progress. 
   Therefore, the conventional wiring harness production apparatus requires a space for stocking the sub-harnesses in the wiring harness assembling line. This tends to increase an installation space of the apparatus in a factory. Furthermore, the stock of the sub-harnesses in the wiring harness assembling line may be undesirable for the reliability of the sub-harnesses. The decreased reliability of the sub-harnesses has an adverse effect on the wiring harness. 
   SUMMARY OF THE INVENTION 
   Accordingly, an object of the present invention is to provide a wiring harness production apparatus having a decreased installation space. 
   For achieving the object, the present invention provides an apparatus for producing a wiring harness. The wiring harness has a plurality of first sub-harnesses and a plurality of second sub-harnesses. The first sub-harness has a plurality of electrical cables, a plurality of first press-fit terminals, and a first isolator. The first press-fit terminal is joined to each end of the first electrical cable. The first isolator holds the first press-fit terminals positioned at one end of the first sub-harness. The second sub-harness has a plurality of second electrical cables, a plurality of second press-fit terminals, a plurality of crimp terminals, a connector housing for accommodating the crimp terminals, and a second isolator supporting the second press-fit terminals. The second press-fit terminal is connected to one end of the second electrical cable, and the crimp terminal is connected to the other end of the second electrical cable. When any of the first and second isolators are layered, the press-fit terminals held by different ones of the isolators can be connected to one another. The apparatus includes: 
   a first sub-harness assembling line for assembling the first sub-harnesses, 
   a second sub-harness assembling line for assembling the second sub-harnesses, and 
   a wiring harness assembling line for layering the isolators of the first and second sub-harnesses to complete the wiring harness. The first and second sub-harnesses are assembled in the first and second sub-harness assembling lines based on an assembling time required for assembling the wiring harness in the wiring harness assembling line. 
   Preferably, the wiring harness assembling line outputs one of the wiring harnesses at a time interval, and the first and second sub-harness assembling lines can output a specified number of the first and second sub-harnesses within the time interval. The specified number of the sub-harnesses are required to assemble the wiring harness. Thus, the first and second sub-harness assembling line allows to output the first and second sub-harnesses to the wiring harness assembling line in synchronization with the assembling speed of the wiring harness. 
   Preferably, the first sub-harness assembling line takes a first time required for assembling a first number of the first sub-harnesses required to assemble the single wiring harness, and the second sub-harness assembling line takes a second time required for assembling a second number of the second sub-harnesses required to assemble the single wiring harness. The time interval is determined based on a longer one of the first and second times. The first and second sub-harness assembling lines allow to output the first and second sub-harnesses to the wiring harness assembling line in a sure synchronization with the assembling speed of the wiring harness. 
   Preferably, the first time is substantially equal to the time interval, and the second time is also substantially equal to the time interval. 
   In the above-mentioned aspect of the invention, the first and second sub-harnesses are assembled based on a time required for assembling a single wiring harness. Thus, the first and second sub-harnesses are supplied from the first and second sub-harness assembling lines to the wiring harness assembling line in conformity with the assembling of the wiring harness. 
   Accordingly, it is unnecessary to stock a larger amount of the sub-harnesses near the wiring harness assembling line. This allows a reduced space for stocking the sub-harnesses near the wiring harness assembling line, reducing the total space for the wiring harness production apparatus. 
   Preferably, the first and second sub-harness assembling lines assemble the first or second sub-harness while the first and second electrical cable are being transferred to come near the wiring harness assembling line. 
   In this aspect of the invention, when the sub-harnesses have been just assembled, they are located near the wiring harness assembling line. This allows an efficient transfer of the sub-harnesses for the wiring harness assembling line. That is, the sub-harnesses can be smoothly supplied to the wiring harness assembling line. Accordingly, an assembling time for the wiring harness is reduced, allowing an improved productivity of the wiring harness. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a block diagram showing a concept of a wiring harness production apparatus of an embodiment according to the present invention; 
       FIG. 2  is a perspective view showing a sub-harness assembling line of the production apparatus of  FIG. 1 , which fits a press-fit terminal at each end of an electrical cable; 
       FIG. 3  is a perspective view showing a sub-harness assembling line of -the production apparatus of  FIG. 1 , which assembles a sub-harness having a press-fit terminal at one end and a crimp terminal at the other end thereof; 
       FIG. 4  is a plan view showing a wiring board used in a wiring harness assembling line of the production apparatus of  FIG. 1 ; 
       FIGS. 5A and 5B  each are a schematic view showing a step for assembling a sub-harness in the sub-harness assembling line of  FIG. 2 ; 
       FIGS. 6A and 6D  each are a schematic view showing a step for assembling a sub-harness in the sub-harness assembling line of  FIG. 3 ; 
       FIG. 7  is a view illustrating a concept of a wiring harness assembled by the wiring harness production apparatus of  FIG. 1 ; 
       FIG. 8  is a perspective view of a press-fit terminal used in a joint connector of the wiring harness of  FIG. 7 ; 
       FIG. 9  is a perspective view showing some of the press-fit terminals of  FIG. 8 , the terminals being layered to electrically connect to each other; 
       FIG. 10  is a perspective view showing some of the press-fit terminals of  FIG. 8 , the terminals being disposed in parallel to electrically connect to each other; 
       FIG. 11  is a perspective view showing a terminal fitting housing of the wiring harness of  FIG. 7 ; 
       FIG. 12  is a perspective view showing the terminal fitting housing of FIG.  11  and press-fit terminals used in a joint connector, which are just going to be inserted into the housing; 
       FIG. 13  is a perspective view showing the terminal fitting housings of  FIG. 12  layered with a space therebetween; 
       FIG. 14  is a perspective view showing a connector defined by securing the terminal fitting housings of  FIG. 12  to one another; 
       FIG. 15  is a perspective view showing a press-fit terminal used in a junction-box of a wiring harness of  FIG. 7 ; 
       FIG. 16  is a perspective view showing a joint bar of the wiring harness of  FIG. 7 ; 
       FIG. 17  is a perspective view showing a terminal fitting plate of the wiring harness embodying the present invention and showing in-junction-box disposed press-fit terminals and electrical cables received in the terminal fitting plate; 
       FIG. 18  is a perspective view showing some of the terminal fitting plates of  FIG. 17  which are layered with a space therebetween; 
       FIG. 19  is a perspective view showing an electrical distribution block defined by securing the terminal fitting plates of  FIG. 17  to one another; 
       FIG. 20  is a perspective view showing an example of a sub-harness of the wiring harness shown in  FIG. 7 , and the sub-harness has a press-fit terminal at each end thereof; 
       FIG. 21  is a perspective view showing another example of a sub-harness of the wiring harness shown in  FIG. 7 , and the sub-harness has a press-fit terminal at each end thereof; 
       FIG. 22  is a perspective view showing further another example of a sub-harness of the wiring harness shown in  FIG. 7 , and the sub-harness has a press-fit terminal at each end thereof; 
       FIG. 23  is a perspective view showing an example of a sub-harness of the wiring harness shown in  FIG. 7 , and the sub-harness has a press-fit terminal at one end and a crimp terminal at the other end; and 
       FIG. 24  is a perspective view showing another example of a sub-harness of the wiring harness shown in  FIG. 7 , and the sub-harness has a press-fit terminal at one end and a crimp terminal at the other end. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Next, referring the accompanied drawings, a wiring harness production apparatus of an embodiment according to the present invention will be discussed. A wiring harness production apparatus  200  illustrated in  FIG. 1  produces a wiring harness  1 , for example, illustrated in FIG.  7 . 
   The wiring harness  1  illustrated in  FIG. 7  is arranged in a motor vehicle to supply a power from a power source like a battery to on-vehicle electric appliances such as various lamps and various motors. 
   As illustrated in  FIG. 7 , the wiring harness  1  has a lot of electrical cables  4 , connectors  5 , an electrical distribution block  6 , a connector  8 , and other fittings like a protector  7 . Each electrical cable  4  is an insulated one having a conductive wire core and an insulating sheath that covers the core. A plurality of the protectors  7  are provided at appropriate positions to adequately secure the electrical cables  4 . 
   The wiring harness  1  has at least one type of sub-harnesses freely selected from sub-harnesses  10   a ,  10   b , and  10   c  each having a press-fit terminal at each end as illustrated in  FIGS. 20  to  22 . The wiring harness  1  may have more than one of the sub-harnesses  10   a ,  10   b , and  10   c . 
   That is, the wiring harness  1  may have any of the sub-harnesses  10   a ,  10   b , and  10   c.    
   Alternatively, the wiring harness  1  may have one or more of sub-harnesses  20   a  and  20   b  each having a press-fit terminal at one end and a crimp terminal at the other end as illustrated in  FIGS. 23 and 24 . Alternatively, the wiring harness  1  may have one or more of the sub-harnesses  10   a ,  10   b , and  10   c  and one or more of the sub-harnesses  20   a  and  20   b.    
   The wiring harness  1  is generally completed by incorporating the sub-harnesses  10   a ,  10   b , and  10   c  with the sub-harnesses  20   a  and  20   b  as described later. Note that the sub-harness  10   a ,  10   b , or  10   c  corresponds to the first sub-harness described in the summary of the invention, and the sub-harness  20   a  or  20   b  corresponds to the second sub-harness. 
   The sub-harness  10   a  illustrated in  FIG. 20  has a parallel row of electrical cables  4   a , press-fit terminals  30   a  for a junction box, and terminal fitting housings  40   a . The press-fit terminal  30   a  is illustrated in  FIGS. 8  to  10 , and the terminal fitting housing  40   a  that is an isolator is illustrated in  FIGS. 11  to  14 . 
   The press-fit terminal  30   a  is fitted to each end of the electrical cable  4   a . The press-fit terminal  30   a  is received in a terminal accommodation chamber  41 , which will be discussed later, of the terminal fitting housing  40   a.    
   The sub-harness  10   b  illustrated in  FIG. 21  has a parallel row of electrical cables  4   a , press-fit terminals  30   a  for a joint connector, a press-fit terminal housing  40   a , press-fit terminals  50   a  for a junction box, and terminal fitting plates  60   a . The press-fit terminal  30   a  is also illustrated in  FIG. 15 , and the terminal fitting plate  60  is also illustrated in  FIGS. 17  to  19 . 
   The press-fit terminals  30   a  each are fitted to an end of the electrical cables  4   a . Each press-fit terminal  30   a  is received in the terminal accommodation chamber  41  of the terminal fitting housing  40   a . The in-junction-box press-fit terminal  50   a  is fitted to the other end of the electrical cables  4   a . The press-fit terminals  50   a  each are received in an electrical cable accommodation chamber  61 , which will be discussed later, of the terminal fitting plate  60   a.    
   The sub-harness  10   c  illustrated in  FIG. 22  has a parallel row of electrical cables  4   a , press-fit terminals  50   a  for a junction box, and terminal fitting plates  60   a . The press-fit terminal  50   a  is fitted to each end of the electrical cables  4   a . The press-fit terminal  50   a  is received in an electrical cable accommodation chamber  61  of the terminal fitting plate  60   a.    
   In the examples illustrated in  FIGS. 20  to  22 , the electrical cables  4   a  each are fitted to the terminal fitting housing  40   a  or to the terminal fitting plate  60   a  at each end thereof. However, the sub-harness  10   a ,  10   b , or  10   c  may have a plurality of the terminal fitting housings  40   a  or the terminal fitting plates  60   a  at each end side of the electrical cables  4   a.    
   The electrical cable  4   a  of the sub-harnesses  10   a ,  10   b , and  10   c  corresponds to the first electrical cable described in the summary of the invention. The press-fit terminal  30   a  and the press-fit terminal  50   a  of the sub-harnesses  10   a ,  10   b , and  10   c  correspond to the first press-fit terminals described in the invention summary. The terminal fitting housing  40   a  and the terminal fitting plate  60   a  of the sub-harnesses  10   a ,  10   b , and  10   c  correspond to the first isolators described in the invention summary. 
   The sub-harness  20   a  illustrated in  FIG. 23  has a parallel row of electrical cables  4   b , press-fit terminals  30   b  for a junction box, terminal fitting housings  40   b , crimp terminals  90 , and connector housings  100 . The terminal fitting housing  40   b  functions as an isolator. 
   Each press-fit terminal  30   b  is fitted to an end of each electrical cable  4   b . The press-fit terminal  30   b  is received in a terminal accommodation chamber  41  of the terminal fitting housing  40   b . The crimp terminal  90  is defined by bending a conductor plate. The crimp terminal  90  is crimped to the other end of the electrical cable  4   b.    
   The connector housing  100  is made of an insulating synthetic resin material and has a box shape. The connector housing  100  has a plurality of terminal accommodation chambers  101  receiving the crimp terminals  90 . The terminal accommodation chamber  101  of the connector housing  100  receives the crimp terminal  90  crimped to the other end of the electrical cable  4   b . The connector housing  100  and the crimp terminals  90  received in the terminal accommodation chambers  101  constitute the connector  8 . 
   The sub-harness  20   b  illustrated in  FIG. 24  has a parallel row of electrical cables  4   b , press-fit terminals  50   b  for a junction box, a terminal fitting plate  60   b  that functions as an isolator, crimp terminals  90 , and a connector housing  100 . 
   Each press-fit terminal  50   b  is fitted to an end of each electrical cable  4   b . The press-fit terminal  50   b  is received in an electrical cable accommodation chamber  61  of the terminal fitting plate  60   b . A crimp terminal  90  and a connector housing  100 , which are illustrated in  FIG. 20 , are the same as those of the sub-harness  20   a . Thus, the same reference numerals are provided for them not to be discussed again. 
   In the examples illustrated in FIG.  23  and  FIG. 24 , the electrical cables  4   b  are fitted to the terminal fitting housing  40   a  or the terminal fitting plate  60   a  at an end side thereof, while the electrical cables  4   b  are fitted to two separate connectors  8  at the other end side thereof. 
   Alternatively, the sub-harness  20   a  or  20   b  of the wiring harness  1  may have one or more than two connectors  8  at the other end side of the electrical cables  4   b.    
   The electrical cable  4   b  of the sub-harnesses  20   a  and  20   b  corresponds to the second electrical cable described in the invention summary. The press-fit terminal  30   b  and the press-fit terminal  50   b  for a junction-box of the sub-harness  20   a  and  20   b  correspond to the second press-fit terminals described in the invention summary. The terminal fitting housing  40   b  and the terminal fitting plate  60   b  of the sub-harness  20   a  and  20   b  each correspond to the second isolator described in the invention summary. 
   Since press-fit terminals  30   a  and  30   b  have the same configuration as each other, only the press-fit terminal  30   a  will be representatively discussed. The press-fit terminal  30   a  is defined by bending a conductor plate. As illustrated in  FIGS. 2 and 3 , the press-fit terminal  30   a  has a flat bottom wall  35  on which an electrical cable  4   a  is disposed, an electrical cable connection portion  31 , and an electrical contact piece  32 . 
   The electrical cable connection portion  31  has a pair of opposing crimping pieces  33  and three pairs of press fitting blades  34   a ,  34   b , and  34   c . The crimping pieces  33  and the press fitting blades  34   a ,  34   b , and  34   c  are vertically extending relative to the bottom wall  35 . 
   The crimping pieces  33  are bent to hold the electrical cable  4   a  disposed on the bottom wall  35 . The press fitting blades  34   a ,  34   b , and  34   c  receive the electrical cable  4   a  which is inserted between each pair of the blades. Thereby, the blades cut into the sheath of the electrical cable  4   a  to contact the wire core to electrically connect to the electrical cable  4   a . That is, the press-fitting of the blades for the electrical cable  4   a  is completed. 
   The electrical contact piece  32  has an opening  36  (see  FIG. 9 ) provided in the bottom wall  35  and has a contact piece  37  raised from the bottom wall  35  and serving as a connection means. The contact piece  37  is changeable from a rising position to a parallel position relative to the bottom wall  35  by a bending work. The parallel position is illustrated by a chain line in FIG.  2 . 
   Note that the contact piece  37  permanently maintains the rising position or the parallel position once the position is determined. As illustrated in  FIG. 21 , the opening  36  has a resilient contact piece  38  for press-fitting the contact piece  37  to an end of the bottom wall  35 . 
   The press-fit terminals  30   a  for a joint connector are layered with a space therebetween in parallel to the bottom wall  35 . The electrical contact piece  32  electrically connects the press-fit terminals  30   a  to one another, since the contact piece  37  of the press-fit terminal  30   a  is inserted into the opening  36  of another upper press-fit terminal  30   a  as illustrated in FIG.  9 . 
   At the same time, the contact piece  37  of the lower press-fit terminal  30   a  is pinched between an end part of the bottom wall  35  and the resilient contact piece  38  of the upper press-fit terminal  30   a.    
   As illustrated in  FIG. 12 , the press-fit terminals  30   a  is forced into a terminal accommodation chamber  41  of a terminal fitting housing  40   a . Thereby, the press-fit terminal  30   a  is received in the terminal fitting housing  40   a  to be secured therein. 
   When received in the terminal accommodation chambers  41 , the press-fit terminals  30   a  are disposed in parallel to one another. Adjacent two of the press-fit terminals  30   a  each have a connection piece  39  to electrically connect each other as illustrated in FIG.  10 . The connection piece  39  is provided in the side of the electrical cable connection portion  31  of the bottom wall  35 . 
   Since the terminal fitting housings  40   a  and  40   b  have the same configuration as each other, only the terminal fitting housing  40   a  will be representatively discussed. The terminal fitting housing  40   a  is made of an insulating synthetic resin material or the like. As illustrated in  FIGS. 11  to  14 , the terminal fitting housing  40   a  has a rectangular plate-like main body  42 , a plurality of partitions  43  rising from the main body  42 , and a plurality of terminal accommodation chambers  41 . The partitions  43  are parallel to one another and define the terminal accommodation chambers  41  between them. 
   A plurality of the terminal fitting housings  40   a , each of which has received the press-fit terminals  30   a  in the terminal accommodation chambers  41 , are layered with the main bodies being parallel to one another to define the connector  5  as illustrated in FIG.  14 . At that time, as illustrated in  FIG. 8 , the electrical cable  4   a  is fitted to each press-fit terminal  30   a  secured in the housing  40   a . Then, as illustrated in  FIG. 13 , the terminal fitting housings  40   a  each of which has received the electrical cable  4   a  are layered. 
   Each terminal fitting housing  40   a  has a plurality of lock projections  44  and locking recesses  45  for securing them to one another when layered as illustrated in  FIGS. 11 and 12 . Furthermore, the terminal fitting housing  40   a  has a plurality of openings (not shown) each receiving the contact piece  37  of a lower one of press-fit terminals  30   a  so that the contact piece  37  can pass through the opening  36  of an upper one of press-fit terminals  30   a.    
   Since the press-fit terminals  50   a  and  50   b  for a junction box have the same configuration as each other, only the press-fit terminal  50   a  will be representatively discussed hereinafter. The press-fit terminal  50   a  is formed from a conductor plate by a bending work. As illustrated in  FIG. 15 , the press-fit terminal  50   a  has a flat bottom wall  55  on which the electrical cable  4   a  is disposed, an electrical cable connection portion  51 , and an electrical contact piece  52 . 
   The electrical contact piece  51  is received in an electrical cable accommodation chamber  61 . The electrical cable connection portion  51  has two pairs of opposing crimping pieces  53   a , and  53   b  and three pairs of opposing press fitting blades  54   a ,  54   b , and  54   c . The crimping pieces  53   a , and  53   b  and the press fitting blades  54   a ,  54   b , and  54   c  are vertically extending relative to the bottom wall  55 . 
   The crimping pieces  53   a , and  53   b  are bent to hold the electrical cable  4   a  disposed on the bottom wall  35 . The press fitting blades  54   a ,  54   b , and  54   c  receive the electrical cable  4   a  which is received between each pair of the blades. Thereby, the blades cut into the sheath of the electrical cable  4   a  to contact the wire core to electrically connect to the electrical cable  4   a . That is, the press-fitting of the blades for the electrical cable  4   a  is completed. 
   The electrical contact piece  52  has a contact bar  56  along a side edge of the bottom wall  55 . The contact bar  56  is a rectangular hollow piece. The electrical contact piece  52  is disposed such that the hollow of the contact bar  56  communicates with a through hole described later of the terminal fitting plate  60   a . Through the hollow of the contact bar  56 , there is inserted a joint bar  80  illustrated in  FIG. 12  for electrical connection thereof. The contact bar  56  has a pair of resilient contact pieces  57  for press-contacting the joint bar  80  thereto. 
   The joint bar  80  is inserted into the hollows of the contact bars  56  after the terminal fitting plates  60   a  have been layered. Thus, the electrical contact pieces  52  allow electrical connection of the terminals between the terminal fitting plates  60   a  to one another. 
   A press-fit terminal  50   a  used in a junction-box is forced into one of the electrical cable accommodation chambers  61  of the terminal fitting plate  60   a . Thereby, The press-fit terminal  50   a  is held by the terminal fitting plate  60   a . The joint bar  80  is substantially a flat bar made of a conductor metal or the like. 
   The terminal fitting plates  60   a  and  60   b  have the same configuration as each other. Thus, only the terminal fitting plate  60   a  will be representatively discussed hereinafter. The terminal fitting plate  60   a  is made of an insulating synthetic resin material or the like. The terminal fitting plate  60   a , as illustrated in  FIGS. 17  to  19 , has a rectangular plate-like main body  62 , a plurality of partitions  63  rising from the main body  62 , a plurality of electrical cable accommodation chambers  61 , a plurality of receiving recesses  64 , and through openings (not shown). 
   The partitions  63  are arranged in parallel to one another with a space therebetween. The space between two adjacent partitions  63  defines the electrical cable accommodation chamber  61 . The recess  64  receives the contact bar  56  of the press-fit terminals  50   a  used in the junction-box. 
   The receiving recess  64  is defined to provide a wider distance between the two adjacent partitions  63 . There are provided a plurality of the receiving recesses  64  along a longitudinal direction of the electrical cable accommodation chambers  61 . The through hole is provided for each receiving recess  64 . The hole passes through the main body  62 . 
   As illustrated in  FIGS. 17 and 18 , the terminal fitting plate  60   a  receives the press-fit terminals  50   a  in the electrical cable accommodation chambers  61  and the receiving recesses  64 . Then, the plate-like main bodies  62  are layered in parallel. The joint bars  80  are inserted into the associated through holes and the hollows of the contact bars  56 , so that the terminal fitting plates  60   a  define a distribution block  6  as illustrated in FIG.  19 . 
   At the same time, the press-fit terminals  50   a  each are connected to the electrical cable  4   a . The terminal fitting plate  60   a  has a plurality of lock projections (not shown) and locking holes  66  engageable with the lock projections. The engagement of the lock projections with the locking holes  66  secures the terminal fitting plates  60   a  to each other. 
   The wiring harness  1  is completed by layering the terminal fitting housings  40   a  or  40   b  or the terminal fitting plates  60   a  or  60   b , which are consisting of the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , or  20   b , to secure them to each other according to a predetermined pattern. 
   In the terminal fitting housings  40   a  and  40   b  which have been layered to be secured to each other, the contact pieces  37  electrically connect the in-joint-connector disposed press-fit terminals  30   a  and  30   b  held by different terminal fitting housings  40   a  and  40   b.    
   In terminal fitting plates  60   a  and  60   b  which have been layered to be secured to each other, the joint bars  80  electrically connect the press-fit terminals  50   a  and  50   b  held by different terminal fitting plates  60   a  and  60   b  to each other. The mutual connection of the different press-fit terminals  50   a  and  50   b  results in mutual electrical connection of the electrical cables  4   a  and  4   b  fitted with the different terminals  50   a  and  50   b.    
   That is, in the wiring harness  1 , a connection portion for electrically connecting the electrical cables  4   a  and  4   b  to each other is defined by the layering of the terminal fitting housings  40   a  and  40   b  or the terminal fitting plates  60   a  and  60   b  and by the connection of the terminals  30   a ,  30   b ,  50   a , and  50   b  through the joint bars  80 . 
   Next, referring to  FIGS. 1  to  6 , a production apparatus  200  of the wiring harness  1  will be discussed. The wiring harness production apparatus  200  has a first sub-harness assembling line and a second sub-harness assembling line as illustrated in FIG.  1 . The first sub-harness assembling line is an assembling line  201  for press-fitting a terminal to each end of an electrical cable. The second sub-harness assembling line is an assembling line  202  for press-fitting a terminal to one end of an electrical cable and for crimping another terminal to the other end of the electrical cable. 
   The sub-harness assembling line  201  assembles the sub-harness  10   a ,  10   b , or  10   c  each having a press-fit terminal at each end thereof. A plurality of the sub-harness assembling lines  201  are provided, and the number of the assembling lines  201  is the same as the different type number of the sub-harnesses  10   a ,  10   b , and  10   c  used for the wiring harness  1 . That is, each sub-harness assembling line  201  assembles one type of the sub-harnesses  10   a ,  10   b , and  10   c.    
   As illustrated in  FIGS. 1 and 2 , the sub-harness assembling line  201  has a press-fit terminal inserting station  210 , a predetermined-length electrical cable preparing station  211 , a press-fitting station  212 , and a first sub-check station  213 . 
   The cable preparing station  211 , and the press-fitting station  212 , and the first sub-check station  213  are sequentially positioned toward the wire harness assembling line  203 . 
   The press-fit terminal inserting station  210  forces the press-fit terminals  30   a  and  50   a  into the terminal accommodation channels  41  and the electrical cable receiving channels  61  of the housing  40   a  and the plate  60   a  to obtain the sub-harnesses  10   a ,  10   b , and  10   c . A terminal fitting station  220  fits the press-fit terminals  30   a  and  50   a  in the housing  40   a  and the plate  60   a.    
   The cable preparing station  211  cuts an electrical cable supplied from an electrical cable supply station (not shown) into a cable having a predetermined length. The predetermined-length electrical cables are held by a retainer bar  110  as illustrated in FIG.  5 A. The electrical cable supply station has a plurality of reels each for winding one of different types of the electrical cables. 
   The retainer bar  110  has a plurality of clips  111  for holding the electrical cables as illustrated in  FIGS. 5A and 5B . The electrical cable clips  111  align with one another in a direction. Each electrical cable clip has a pair of pinching pieces  112   a  and  112   b  for pinching the electrical cable  4   a  therebetween. 
   As illustrated in  FIG. 5B , the press-fitting station  212  press-fits each end of the electrical cable  4   a  to the press-fit terminal  30   a  or  50   a  received in the housing  40   a  or the plate  60   a  according to a predetermined pattern. 
   The first sub-check station  213  provides an electrical continuity check for the sub-harnesses  10   a ,  10   b , and  10   c  which have been obtained through the cable preparing station  211  and the press-fitting station  212 . The electrical continuity check determines acceptance or rejection of each press-fit terminal  30   a  or  50   a  which is checked of electrical continuity with other terminals  30   a  and  50   a.    
   The sub-harness assembling line  201  strikes the electrical cables  4   a , which have been obtained by the cable preparing station  211 , into the retainer bar  110 . Then, Each retainer bar  110  having the cables is transferred toward the press-fitting station  212 . 
   The press-fitting station  212  also receives the housing  40   a  and the plate  60   a , which have been mounted with the press-fit terminals  30   a  or  50 , from the press-fit terminal fitting station  210 . The press-fitting station  212  press-fits the electrical cable  4   a  held by the retainer bar  110  to the press-fit terminal  30   a  or  50   a . Thereafter, each retainer bar  110  is transferred toward the sub-check station  213 . 
   The sub-check station  213  checks the electrical continuity of each of the sub-harnesses  10   a ,  10   b , and  10   c  to determine acceptance or rejection thereof. 
   The sub-harness assembling line  201  assembles the sub-harnesses  10   a ,  10   b , and  10   c , while the electrical cables  4   a  are transferred toward the wiring harness assembling line  203 . 
   The sub-harness assembling line  202  assembles the sub-harnesses  20   a  and  20   b  each having a press-fit terminal and a crimp terminal. The number of the sub-harness assembling lines  202  is equal to the number of types of the sub-harnesses  20   a  and  20   b  used for the wiring harness  1 . That is, a different one of the sub-harness assembling lines  202  corresponds to a different type of the sub-harnesses  20   a  and  20   b.    
   As illustrated in  FIGS. 1 and 3 , the sub-harness assembling line  202  has the press-fit terminal inserting station  220 , a predetermined-length electrical cable preparing station  221 , a press-crimping station  222 , a press-fitting station  223 , a terminal inserting station  224 , and a second sub-check station  227 , which are sequentially disposed toward the wiring harness assembling line  203 . 
   The press-fit terminal inserting station  220  press-fits the press-fit terminals  30   b  and  50   b  to the terminal accommodation channels  41  and the electrical cable receiving channels  61  of the housing  40   b  and the plate  60   b  used in the sub-harness  20   a  and  20   b.    
   The cable preparing station  221  cuts an electrical cable supplied from an electrical cable supply station (not shown) to obtain a predetermined-length one. The obtained cables are held by the retainer bar  110  as illustrated in FIG.  6 A. The cable preparing station  221  has a stripping machine  225  for stripping one end of the electrical cable  4   b  held by the retainer bar  110 . 
   The electrical cable supply station has a plurality of reels each for winding a different type of electrical cables. Note that a retainer bar  110  used in the sub-harness assembling line  202  has the same configuration as that of the sub-harness assembling line  201 . Thus, the retainer bar  110  will not be discussed again. 
   The press-crimping station  222  has a plurality of crimping machines  226 . The crimping machine  226  has a fixed lower molding die and an upper molding die movable relative to the lower die. The crimping machine  226  holds the stripped end of the electrical cable  4   b  and the crimp terminal  90  between the upper and lower molding dies to crimp the electrical cable  4   b  to the crimp terminal  90 . 
   The crimping machines  226  align with one another in a direction in which there are disposed the cable preparing station  221 , the press-crimping station  222 , and the press-fitting station  223 , and the terminal inserting station  224 . The aligned crimping machines  226  are different from one another in the upper and lower molding dies and the distance therebetween according to the types of the electrical cable  4   b  and the crimp terminal  90 . 
   As illustrated in  FIG. 6B , the press-crimping station  222  crimps the crimp terminal  90  to one end of the electrical cable  4   b  held by the clips  111  of the retainer bar  110 . 
   As illustrated in  FIG. 6C , the press-fitting station  223  press-fits one of the press-fit terminals  30   b  and  50   b , which is received in the housing  40   b  or the plate  60   b , to the other end of the electrical cable  4   b  according to a predetermined pattern. 
   As illustrated in  FIG. 6D , the terminal inserting station  224  inserts the crimp terminal  90  crimped to the electrical cable  4   b  into the terminal accommodation chamber  101  of the connector housing  100 . Thereby, the terminal inserting station  224  fits the connector housing  100  to the other end of the electrical cable  4   b.    
   The second sub-check station  227  makes an electrical continuity check for each sub-harness  20   a  or  20   b  obtained through the cable preparing station  221 , the press-crimping station  222 , the press-fitting station  223 , and the terminal inserting station  224 . The electrical continuity check determines acceptance or rejection of each press-fit terminal  30   b ,  50   b , or  90  which is checked of electrical continuity with other terminals  30   b ,  50   b , or  90 . 
   The sub-harness assembling line  202  strikes the electrical cables  4   b , which have been obtained by the cable preparing station  221 , into the retainer bar  110 . Meanwhile, one end of the electrical cable  4   b  is striped to crimp the crimp terminal  90  thereto. Each retainer bar  110  having the electrical cables  4   b  is transferred toward the press-crimping station  222 . 
   The press-crimping station  222  press-fits the crimp terminal  90  to the striped end of the electrical cable  4   b , and then each retainer bar  110  is transferred toward the press-fitting station  223 . The press-fitting station  223  also receives the housing  40   b  and the plate  60   b  mounted with the press-fit terminals  30   b  and  50   b  from the press-fit terminal inserting station  220 . The press-fitting station  223  fits the striped end side of the electrical cable  4   b  held by the retainer bar  110  to the press-fit terminal  30   b  or  50   b.    
   The press-fitting station  223  outputs each retainer bar  110  toward the terminal inserting station  224 . The terminal inserting station  224  inserts each crimp terminal  90  into the terminal accommodation chamber  101  of the connector housing  100 . 
   Then, each retainer bar  110  is transferred toward the sub-check station  227 . The sub-check station  227  makes an electrical continuity check to determine acceptance or rejection of the sub-harnesses  20   a  and  20   b.    
   Thus, the sub-harness assembling line  202  assembles the sub-harnesses  20   a  and  20   b  while the electrical cable  4   b  is transferred to come near the wiring harness assembling line  203 . 
   In the embodiment, the sub-harness assembling line  202  has an electrical cable rearranging station  228  as illustrated in FIG.  3 . The rearranging station  228  is disposed between the press-crimping station  222  and the press-fitting station  223 . 
   The rearranging station  228  rearranges the electrical cables  4   b  held by the retainer bar  110  so that the stations  223 ,  224  may carry out smooth press-fit and insertion steps. The rearranging station  228  once removes the electrical cables  4   b  from the clips  111  to rearrange them, and the rearranging station  228  strikes again the electrical cables  4   b  into the clips  111 . 
   As illustrated in  FIG. 1 , the wiring harness assembling line  203  has a plurality of wiring boards  230 , a press-fit connector assembling tool, a plurality of press-fit-type distribution block assembling tools, and a wiring harness check station  233 . 
   The wiring board  230  is a plate movable along a rail  234  on a floor of a factory. There are provided eight wiring boards  230  in FIG.  1 . 
   On the wiring board  230 , there is pictured a wiring arrangement pattern for arranging the electrical cables  4 , the connectors  8 , and other additional fittings including the protectors  7 . As illustrated in  FIG. 4 , the wiring board  230  also has a plurality of bundling clips  235 , a plurality of press-fit housing supports  236 , and press-fit plate supports  237 . 
   The clip  235  bundles some of the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , and  20   b . The clips  235  support the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , or  20   b  according to the wiring arrangement pattern to assemble the wiring harness. 
   The press-fit housing support  236  supports the housings  40   a  and  40   b  of the sub-harnesses  10   a ,  10   b ,  20   a , while the housing main plate bodies  42  are spaced from each other. 
   The press-fit housing support  237  supports the housings  60   a  and  60   b  of the sub-harnesses  10   b ,  10   c , and  20   b , while the housing main plate bodies  62  are spaced from each other. 
   The connector assembling tool  231  is disposed near the traveling course or rail  234  of the wiring board  230 . The connector assembling tool  231  press-fits the housings  40   a  and  40   b  held by the housing support  236  to one another so that the lock projections  44  engage with the locking recesses  45 . The connector assembling tool  231  assembles the connectors  5 . 
   The distribution block assembling tool  232  is disposed near the traveling rail  234  of the wiring board  230 . The distribution block assembling tool  232  press-fits the plates  60   a  and  60   b  held by the plate support  237  to each other so that the lock projection may engage with and lock in the locking hole  66 . The distribution block assembling tool  232  inserts the joint bars  80  into the predetermined through holes to contact the contact bars  56  of the press-fit terminals  50   a  and  50   b  for assembling the distribution line unit  6 . 
   The control unit  233  is a calculation unit having known devices including a RAM, a ROM, and a CPU. The control unit  233  controls the wiring harness assembling line  203 . The control unit  233  communicates with the sub-harness assembling line  201  and the sub-harness assembling line  202  to control them. The control unit  233  controls the whole wiring harness assembling apparatus  100 . 
   The control unit  233  controls the sub-harness assembling line  201  and the wiring harness assembling line  203  while the following equation 1 having parameters t, T 1 , and N is applied. N, t, and T 1  are sequentially the number of the wiring boards  230 , a time required for the wiring board  230  to complete one circulation travel on the rail  234 , and a first assembling time required for the sub-harness assembling line  201  to assemble the sub-harnesses  10   a ,  10   b , and  10   c  used in a single wiring harness  1 .
 
 t÷N≈T   1   equation 1
 
   The control unit  233  controls the sub-harness assembling line  201  and the wiring harness assembling line  203  while the following equation 2 having parameters t, T 2 , and N is applied. T 2  is a second assembling time required for the sub-harness assembling line  202  to assemble the sub-harnesses  20   a  and  20   b  used in a single wiring harness  1 .
 
 t÷N≈T   2   equation 2
 
   That is, the control unit  233  controls the whole wiring harness production apparatus such that the first assembling time T 1  is almost equal to the second assembling time T 2 . 
   Meanwhile, a time T for the wiring harness assembling line  203  to output a completed wiring harness  1  is calculated from the following equation 3.
 
 t÷N=T   equation 3
 
   The sub-harness assembling line  201  is different from the sub-harness assembling line  202  in the number of steps for assembling the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , and  20   b . Thus, the first assembling time T 1  is different from the second assembling time T 2 . Generally, the second assembling time T 2  is longer than the first assembling time T 1 . It is not practical to reduce a time for each step of the sub-harness assembling lines  201 ,  202 . 
   Thus, the control unit  233  generally controls the whole wiring harness production apparatus  1  with the time interval T being determined based on a longer one of the first and second assembling times T 1  and T 2 . That is, the control unit  233  controls the traveling speed of the wiring boards  230  based on the longer of the assembling times T 1  and T 2  for the sub-harness assembling lines  201 ,  202  to assemble the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , and  20   b . 
   The control unit  233  controls the wiring harness production apparatus  200  with satisfying the equations 1 and 2, so that the wiring harness assembling line  203  outputs a completed wiring harness  1  while the sub-harness assembling lines  201 ,  202  assemble the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , and  20   b  which are just necessary for a single wiring harness  1 . 
   Thus, the sub-harness assembling lines  201  and  202  assemble the wiring sub-harness  10   a ,  10   b ,  10   c ,  20   a , and  20   b  based on the time interval T for outputting a complete wiring harness  1  from the wiring harness assembling line  203 . 
   The embodiment satisfies the equations 1, 2, and  3  to assemble the wiring harness  1 , so that the wiring harness assembling line  203  assembles the wiring harness  1  while the sub-harness assembling lines  201  and  202  supply the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , and  20   b  to the wiring harness assembling line  203 . 
   Thus, in assembling the wiring harness  1 , only a required number of the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , and  20   b  can be continuously supplied to the wiring harness assembling line  203 . 
   Accordingly, it is unnecessary to stock a larger amount of the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , and  20   b  near the wiring harness assembling line  203 . This allows a reduced space for stocking the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , and  20   b  near the wiring harness assembling line  203 , also reducing the total space of the wiring harness production apparatus  200 . 
   In addition, the sub-harness assembling lines  201  and  202  assemble the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , and  20   b  while the electrical cables  4   a  and  4   b  are transferred toward the wiring harness assembling line  203 . 
   Thus, when the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , and  20   b  have been just assembled, they are located near the wiring harness assembling line  203 . This allows an efficient transfer of the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , and  20   b  for the wiring harness assembling line  203 . That is, the sub-harnesses  10   a ,  10   b ,  10   c ,  20   a , and  20   b  can be smoothly supplied to the wiring harness assembling line  203 . 
   Accordingly, the assembling time for the wiring harness  1  is reduced, allowing an improved productivity of the wiring harness  1 . 
   In the aforementioned embodiment, for assembling the sub-harnesses  10   a ,  10   b , and  10   c , there are provided the cable preparing station  211  and the press-fitting station  212 . However, the stations  211  and  212  may be replaced by a random terminal press-fit machine  300  disclosed in Japanese Patent Application Laid-open No. H. 7-296933, which is partially illustrated in FIG.  26 . Note that the random terminal press-fit machine  300  may include the press-fit machine described in the summary of the invention. 
   In the present invention, the sub-harness assembling line  202  may assemble plural types of the sub-harnesses  10   a ,  10   b , and  10   c . The wiring board  230  may be mounted on an automatically running bogie traveling along a desirable way on a floor of a factory. 
   Note that the wiring harness  1  according to the present invention may have an electrical cable having a crimp terminal fitted at each end thereof.