Electrical harness termination apparatus and method

Abstract: Disclosed is an improved method and apparatus of automatically terminating connector pieces to a plurality of insulated wires in which insulated wires of desired lengths are prepared. Right connector pieces (R) are terminated to the right ends of the cores of said insulated wires and left connector pieces (L) are terminated to the left ends of the core conductors of the insulated wires or the left ends of the insulated wires may remain unterminated. Right connector pieces each having terminals fixed thereto are displaced from an initial position to a terminating position. The right connector pieces are terminated to the right core conductor ends of the insulated wires at the terminating position. The right connector piece terminated to the right core conductor ends of said insulated wires are displaced to the initial position which results in pulling the insulated wires out of a wire supply against a resilient tension which is applied to the insulated wires for withdrawal toward said wire supply. The insulated wires are pushed down at the intermediate position between the initial-position and the terminating position to a predetermined lowest level against the resilient tension. A selected insulated wire or wires which are desired to have the longest length are held at the lowest level while allowing the other insulated wires to resiliently rise up to a predetermined second lowest level, thus measuring the second longest length of wire. This measuring operation is repeated until all the insulated wires are clamped and set at of their desired lengths. The insulated wires are then cut at their left ends and the left connector pieces are optionally terminated to the left core conductor ends of said insulated wires, or they remain unterminated.

Description: Field of the Invention The present invention relates to an apparatus and method for automatically connecting the terminals of an electric connector to insulated wires, and more particularly, to an apparatus and method for automatically connecting the terminals of an electric connector to one or both ends of desired lengths of insulated wire in which the lengths of selected insulated wires of a harness may be different to meet particular demands. Background of the Invention An electric harness comprises a desired length of insulated wire having connector pieces terminated to one or both ends, and is used in making an electric connection between different electric apparatuses, or between an electric apparatus and associated connecting means. The lengths of insulated wires between the two ends of the electric harness depend upon the situation in which the associated apparatuses are used. In this connection, an apparatus for making electric harnesses includes means for measuring a desired length of insulated wire, to one or both ends of which a connector piece or pieces are to be connected. One example of such length measuring means uses feed rolls to feed an insulated wire, and the length of the insulated wire can be determined in terms of the number of rotations of the feed rolls. Another example of length measuring means uses a "looper" to push down a stretched length of insulated wire to a selected low level in the form of a "V", thereby determining the length of the insulated wire. The "looper" has a fixed length of up-and-down stroke. The feed roll type length measuring means can change the length of a selected insulated wire as desired. The insulation of the insulated wire, however, may vary somewhat with the surrounding humidity or temperature. If oil or grease should make contact with the insulation of the insulated wire, the friction between the insulation and the feed roll surface will vary. The feeding length of the insulated wire will then likely vary due to slippage between the insulation and the feed roll surface. As a result, the length of the measured wire may be shorter than the desired length, and the harness having such a shorter insulated wire will be rejected. This problem is partly solved with the arrangement disclosed in EP-A- 147081, wherein first the wires are connected to a connector, the wires and the connector are subsequently pulled by a chuck to the longest length of wire necessary. This wire is then stopped from further winding up on the feed roll. The chuck returns further towards its original position, the other wires winding up on their respective feed rolls until they also are stopped at their desired length. This arrangement is less useful for long lengths of wire, the chuck having to travel over a long distance. As for the "looper" type length measuring means, its "looper" is designed to be raised and lowered a predetermined distance, and therefore, it cannot measure different lengths of insulated wires. Changes to the length of the wires can be achieved by mechanically altering the looper, but such changes can be time consuming. Accordingly the use of "harnesses" made by such "looper" type systems is limited. Summary of the Invention In view of the above, one object of the present invention is to provide a method of automatically measuring and cutting desired lengths of insulated wire with accuracy and attaching terminals of the connector pieces to one or both ends of the desired lengths of insulated wire. Another object of the present invention is to provide an apparatus for automatically measuring and cutting desired lengths of insulated wire with accuracy and attaching terminals of connector pieces to one or both ends of the desired lengths of insulated wire. According to the present invention, terminals of connector pieces are connected to one end of all insulated wires simultaneously; selected insulated wires are measured to provide the insulated wires of the desired length; and finally terminals of connector pieces are connected to the other ends of the desired lengths of insulated wire simultaneously. A method is provided of automatically connecting terminals of connector pieces to insulated wires in which a plurality of insulated wires of desired lengths are prepared; terminals at one end of the harness to be prepared are connected to the adjacent ends of the insulated wires; and terminals at the other end are connected to the other end of the insulated wires, or the other ends of said insulated wires remain unterminated. An apparatus for automatically connecting terminals of connector pieces to insulated wires is also disclosed that includes measuring means for measuring desired lengths of insulated wires, and terminating means for connecting right terminal connector pieces to the right core conductor ends of said insulated wires, and cutting said desired lengths of insulated wires and connecting left connector pieces to the left core conductor ends of said desired lengths of insulated wires. The present invention also includes transferring means for transferring right terminal connector pieces each having a terminal from an initial position to a terminating position, and transferring said right terminal connector pieces back to said initial position after said terminating means has connected said right terminal connector pieces to the right core conductor ends of said insulated wires. Wire supplying means is provided responsive to the pulling of said insulated wire for unwinding the insulated wire, yet still applying a constant tension on the insulated wires having right terminal connector pieces terminated thereto. Measuring means push down said insulated wires against the wires at an intermediate position between the terminating positior and said initial position to predetermined lower levels corresponding to the desired lengths of the insulated wires between their opposite terminal connector pieces. Clamp mechanisms are utilized to clamp the insulated wires on the wire supplying side to keep the insulated wires at the desired predetermined lower levels. A lift mechanism for raising the left connector pieces to said terminating position whereby after all of the insulated wires are pushed down to the lowest position, a selected insulated wire or wires may be kept at the lowest position by said clamping means and allowing the other insulated wires to follow the measuring means as it rises due to the influence of the constant tension. This measuring procedure may be repeated until all the desired lengths have been set. Brief Description of the Drawings Other objects and advantages of the present invention may be understood from the following description of preferred embodiment of the present invention, which is shown in accompanying drawings in which: Fig. 1 is a diagrammatical view of a harness forming apparatus of the present invention showing the apparatus in its initial position; Fig. 2 is similar to Fig. 1, but shows the apparatus in which the terminals of the "right" connector piece are transported to the termination station; Fig. 3 is similar to Fig. 2, but shows the lift mechanism in a lowered position to put the right ends of the insulated wires in termination position; Fig. 4 is similar to Fig. 3, but shows the termination head actuated to terminate terminals to the right end of each of the insulated wires; Fig. 5 is similar to Fig. 4, but shows the insulated wires unclamped on the wire-feeding side of the termination station; Fig. 6 is similar to Fig. 5, but shows the termination head raised to its initial raised position; Fig. 7 is similar to Fig. 6, but shows the right connector piece transported to the initial position; Fig. 8 is similar to Fig. 7, but shows the insulated wires clamped on the right side and at the same time, the "left" connector piece is raised; Fig. 9 is similar to Fig. 8 but shows the insulated wires being engaged by the looper mechanism to push them down at their intermediate points to the lowermost level to set the longest length of the insulated wires; Fig. 10 is similar to Fig. 9, but shows certain of the insulated wires clamped on the wire-feeding side to maintain the longest length of the insulated wires; Fig. 11 is similar to Fig. 10, but shows the looper mechanism partially raised and some of the wire feed clamps released to determine the second longest length of the insulated wires; Fig. 12 is similar to Fig. 11, but shows certain of the insulated wires clamped on the wire-feeding side to maintain the second longest length of the insulated wires; Fig. 13 is similar to Fig. 12, but shows the looper mechanism retracted further to the third lowermost level to determine the third longest length of insulated wires; Fig. 14 is similar to Fig. 13, but shows certain of the insulated wires clamped on the wire-feeding side to maintain the third longest length of these insulated wires; Fig. 15 is similar to Fig. 14, but shows the termination head lowered to connect the terminals of the "left" connector piece to the left ends of the insulated wires; Fig. 16 is similar to Fig. 15, but shows the termination head is raised to the initial rased position and the harness unclamped; Fig. 17 is similar to Fig. 16, but shows the termination head and the left mechanism returned to its initial position; Fig. 18 is similar to Fig. 17, but shows the harness removed; Fig. 19 is similar to Fig. 18, but shows apparatus in its initial position; Fig. 20 shows schematically one example of harness comprising a plurality of insulated wires of different lengths with connector pieces attached to both ends of the insulated wires; Fig. 21 shows schematically another example of harness; Fig. 22 is a perspective view showing a wire feeding unit; Fig. 23 is a side view of a wire clamping unit located on the wire-feeding side; Fig. 24 is a plan view of the wire clamping unit of Fig. 23; Fig. 25 is a vertical section showing a pneumatic piston-and-cylinder assembly in the wire clamping unit; Fig. 26 is a side view of a wire measuring unit or looper; Fig. 27 is a front view of the wire measuring unit of Fig. 26; Fig. 28 is a side view of the roll of the wire measuring unit; Fig. 29 is a longitudinal section of the roll of the wire measuring unit, taken along the line 29-29 in Fig. 28. Detailed Description of the Preferred Embodiment Fig. 1 diagrammatically shows an apparatus of the present invention for automatically measuring desired lengths of insulated wires and connecting electrical connector pieces to the ends of such desired lengths of insulated wires. It comprises a transporting unit 1 for transporting right connector pieces R, a wire measuring unit 2, a termination unit 3, a connector lift 4 just below the termination unit 3, and wire feeding unit 5. These units are arranged from right to left in the order named. A wire clamper 6 is located between the transporting unit 1 and the wire measuring unit 2. An auxiliary support mechanism 7 for supporting insulated wires while being measured is located between the wire measuring unit 2 and the connector lift 4. A wire lift 8 and a wire clamper 9 are located between the connector lift 4 and the wire supplying unit 5. The connector transporting unit 1 includes a carriage la for carrying connector pieces R each having at least one terminal, and a pneumatic piston- and cylinder 1b for driving the carriage la. The connector transporting unit 1 receives a single or plurality of connector pieces R to carry and locate under the termination unit 3. Then, each terminal is connected to one end of each insulated wire. Thereafter, the connector transporting unit 1 carries the connector piece R and insulated wires back to the initial position. The carriage la is known per se, and may be any conventional structure so far as it may be appropriate for the purpose. An apparatus for supplying right connector pieces R to the carriage la may be any conventional structure which is capable of supplying connectors of different circuit sizes. This unit may be designed for supplying connector pieces one after another on demand. When right terminal connector pieces R are supplied to the carriage la, these pieces are arranged in a direction perpendicular to the plane shown in Fig. 1. The wire measuring unit 2 comprises a looper assembly having a roll lifting member 2a and a roll 2b rotatably attached to the lower end of the roll lifting member 2a. The wire measuring unit 2 can be put in operation when the connector transporting unit 1 brings the right connector pieces R back to the initial starting position after they have been attached to the ends of the insulated wires. The roll 2b is lowered to contact the insulated wires at a location intermediate terminating unit 3 and wire clamp 6 in order to push the wires down to a predetermined lowest position. It is then raised a predetermined distance to allow some selected insulated wires to rise to a predetermined second lowest position, leaving the other insulated wires to remain at the lowest position. This occurs because all of the insulated wires are subjected to tension which tends to pull back the insulated wires towards the wire supplying unit 5. The selected insulated wires that are pulled rearward under tension follow the rising roll 2a whereas the other wires are held stationary by clamp 9. In order to obtain wires of still shorter length, the roll 2b is raised another predetermined distance to permit some of the previously selected insulated wires to rise to a predetermined third lowest position while the first selected other insulated wires remain at the second lowest position. Thus, the insulated wires retained at the second lowest position are the second longest ones and those retained at the third lowest position are the third longest ones. It can be seen that more than three different lengths of wires can be achieved by clamping the wires as desired as the roll 2b is raised. One example of the wire measuring unit 2 is shown in more detail in Figs. 26-29. It comprises a vertical rail 2c, a roll lift 2a slidably mounted on rail 2c that rises and descends along the rail 2c under the control of an associated robot using a servomotor and a roll 2b rotatably mounted to the end of the roll lift 2a as indicated at 2d. The roll 2b has a plurality of grooves 2e at regular intervals on its circumference (Fig. 29). The termination unit 3 includes a right termination tool 3a to terminate to the right conductor ends (as viewed in Figs. 1-19) of the insulated wires the right connector pieces R which are brought to the termination station by the carriage la, a left cutting and termination tool 3b to cut the insulated wires at their left ends and connect them to the left connector pieces L which are brought to the termination station by the left connector lift 4, a pneumatic piston and cylinder 3e to move the right termination tool 3a and the left cutting and terminating tool 3b back and forth, and a vertically movable base 3c driven by an associated pneumatic piston and cylinder 3d. The right termination tool 3a, the left cutting and terminating tool 3b and the pneumatic piston and cylinder 3e are mounted at the bottom of movable base 3c. Each termination tool has a plurality of termination units of known type spaced at regular intervals. Each termination unit functions to put the end of an insulated wire in the slot defined by the terminal of a connector piece, and forces the end of the insulated wire into the terminal until its opposite piercing projections thrust through the insulation of the insulated wire to contact the core conductor of the insulated wire and thus making the required electric contact. The connector lift 4 comprises a nest 4a to contain left connector pieces L, each having at least one terminal to be connected to the left end of an insulated wire, and a pneumatic piston and cylinder 4b to raise and lower the nest 4a. In the preferred embodiment, the connector lift is equipped with a horizontally movable pneumatic piston and cylinder 4c to hold the nest 4a at its raised position when the pneumatic piston and cylinder 4b raises the nest 4a up to the termination station. Left connector pieces L can be supplied to the nest 4a from a conventional connector piece supply (not shown). It may be of any conventional structure which is capable of supplying a desired number of left connector pieces L of same or different number of circuits. The wire supplying unit 5 consists of as many sub-units as the number of insulated wires to be handled. Each sub-unit includes a wire-feeding reel 5a and a wire-retaining assembly 5b as shown in Fig. 22. The wire-feeding reel 5a is fixed to the end of shaft 5e of an electric motor 5d. The wire retaining assembly 5b includes a stationary base frame 5f having a lateral stationary arm 5g and an inclined movable arm 5n, two guide rolls 5h and 5k rotatably mounted to the lateral arm 5g, and a guide roll 5p rotatably mounted to the free end of the inclined movable arm 5n. The inclined movable arm 5n is spring biased toward its full open position by a spring 5L. A brake drum 5q is fixed to the shaft 5e of the electric motor 5d, and a brake band 5r winds around the brake drum 5q. One end of the brake band 5r is connected to a rod 5s, which is operatively connected to the inclined movable arm 5n via a cam member (not shown). The insulated wire is coiled around the wire-feeding reel 5a and then runs to guide roller 5h guide roller 5k, guide roller 5p and back to guide roller 5k, in the order named, and then towards the termination unit 3. When the insulated wire is not pulled by the wire measuring unit 2, the spring-biased arm 5n is at its position furthest from lateral stationary arm 5g as indicated at 5m, with the guide roll 5p positioned furthest from the guide roll 5k. Through such a structure with the wire running therethrough, a length of the insulated wire is retained which can be fed to the downstream units without feeding from reel 5a. In this condition, the brake band 5r is tightly wound around the brake drum 5q to stop the rotation of the shaft 5e of the electric motor 5d, thus preventing the feeding of the insulated wire from the wire-feeding reel 5a. When a pulling force is applied to the insulated wire to overcome the counterforce generated by the spring 51, the spring-biased arm 5n is pulled towards its closed position as indicated at 5t to feed the insulated wire. Then, the rod 5s is actuated through the action of the cam (not shown) to loosen the brake band 5r, thereby permitting the shaft 5e of the electric motor to rotate and feed a sufficient length of insulated wire to allow the spring biased arm 5n to return to its position as indicated at 5m. Thus, a predetermined length of insulated wire is retained in the geometric structure 5b. The wire-feeding system just described is of a positive wire-feeding type in which the electric motor rotates the wire-feeding roll 5a to feed the insulated wire. Alternatively, use may be made of a wire-feeding system which is designed to be responsive to the pulling of the insulated wire by wire measuring unit 2. In this case. the wire-feeding system omits the motor 5d, the brake 5g and rod 5s and replaces them with a pneumatic piston and cylinder 5c, as seen from Figs. 1 to 19. Otherwise, wire-retaining assembly 5b remains substantially unchanged. Such a modified wire-feeding system utilizes spring 5L to pull the insulated wire back upstream (i.e., in a direction which is opposite to the wire feeding direction). In addition, insulated wire is only fed when the insulated wire is pulled toward the termination station by a force which is strong enough to overcome spring 5L. The wire clamper 6 on the right side of Figs. 1-19 functions to clamp a plurality of insulated wires to avoid stress being placed on the terminations while the wires are engaged and pulled by measuring unit 2. As shown in Fig. 1, it comprises upper and lower assemblies, each having a pusher 6a and a pneumatic piston-and-cylinder 6b. The auxiliary support mechanism 7 is positioned between the wire-measuring unit 2 and the termination unit 3. It includes a support plate 7a and a pneumatic piston-and-cylinder 7b. After the right connector pieces R are terminated to the ends of the insulated wires W1 to W3 and after the connector piece R is returned to its initial position by the carriage la, desired different lengths of insulated wires are measured as previously described with respect to wire measuring unit 2. During such measuring operation, the auxiliary support mechanism 7 functions to support all or selected ones of the insulated wires until left connector pieces L have been connected to the left ends of the insulated wires. The wire lift 8 includes a wire gripper 8a and a piston-and-cylinder 5b to raise and lower the wire gripper 8a. After the right connector pieces R are brought to the terminating position by the carriage la, and just prior to termination thereof, the wire lift 8 lowers the right ends of the insulated wires to the appropriate level to permit the right connector pieces R to be connected to the right ends of the insulated wires and hold all of the insulated wires at such a level until the right and left connector pieces have both been connected to the respective ends of desired lengths of insulated wire. The wire clamper 9 on the wire-feeding side functions to clamp selectively the insulated wires. It includes a pusher 9a and a pneumatic piston-and-cylinder 9b. The wire clamper 9 serves two functions. First, it clamps and holds the insulated wires at the appropriate level for attaching the connector pieces to the insulated wire. Second, clamping and unclamping selected insulated wires in conjunction with the operation of the wire measuring unit 2 facilitates the construction of the desired harnesses having different length wires. One example of the wire clamper 9 is shown in Figs. 23, 24 and 25. A plate 9c of the wire clamper 9 has as many parallel grooves 9d as the number of insulated wires to be handled. A pneumatic piston-and-cylinder 9b is positioned above each of these grooves 9d. One example of the pneumatic piston-and-cylinder 9b is shown in Fig. 25. The piston includes an integration of a relatively large diameter portion 9e, a relatively small diameter portion 9f, a pin-like clamping tip 9a, and a coiled spring 9g around the relatively small diameter portion 9f to push up the integration, thereby biasing the clamping tip 9a away from the underlying insulated wire. An inlet aperture 9k is made to permit the introduction of compressed air to the upper end surface of the piston whereas an aperture 9L permits the clamping tip 9a to project into the groove 9d. Fig. 20 shows a harness having nine insulated wires in which a two-circuit connector piece R2 is attached to the right ends of two insulated wires W2 of predetermined length A2, a four-circuit connector piece R3 is attached to the right ends of four insulated wires W3 of predetermined length A3, a three-circuit connector piece R1 is attached to the right ends of three insulated wires W1 of predetermined length A1, and a nine-circuit connector piece L terminated to the right ends of nine insulated wires W1, W2 and W3 of predetermined lengths A1, A2 and A3 (A1>A2>A3). Referring to Figs. 1 to 19, a series of automatic measuring and terminating operations are described below. In Figs. 2 to 19, reference numerals have been added to selected parts and units which are referred to in the description of the operation pertaining to each of these drawings. The right connector pieces R1, R2 and R3 are arranged in line perpendicular to the plane in which the drawing is laid, and are collectively indicated by R. Fig. 1 shows the initial position of the measuring-and-terminating apparatus in its initial position after the harnesses formed in the preceding cycle have been removed and the apparatus is ready to start the subsequent cycle. All of the insulated wires are raised by the wire lift 8, and the right ends of the insulated wires are in their horizontal termination position. Fig. 2 shows that the pneumatic piston-and-cylinder drive 1b has driven the carriage 1a to the termination station as indicated by 10, thus transporting the right connector pieces R, which are contained in the nest of the carriage 1a, to the termination station. Next, Fig. 3 shows that the pneumatic piston-and-cylinder drive 8b of the wire lift 8 lowers the wire gripper 8a as indicated by 11, thus gripping and putting all of the insulated wires W1, W2 and W3 in the proper vertical position. As shown in Fig. 4, the pneumatic piston-and-cylinder drive 3d of the termination unit 3 drives the right termination tool 3a to terminate the right connector pieces R1, R2 and R3 to the ends of the insulated wires W1, W2 and W3. As previously described, each insulated wire is pressed into a slot defined by the terminal of the connector piece and a pair of insulation displacement blades of the terminal thrust through the insulation of the insulated wire to contact the core conductor of the insulated wire as is known in the art. Referring to Fig. 5, the pneumatic piston-and-cylinder drive 9b of the wire clamper 9 on the wire-feeding side raises all of the clamping heads 9a away from all of the insulated wires W1, W2 and W3 as indicated by arrow 13. In Fig. 6 the pneumatic piston-and-cylinder drive 3d of the termination unit 3 raises the termination tools 3a and 3b to their initial raised position. Referring to Fig. 7, the pneumatic piston-and-cylinder drive 3e of the termination unit 3 moves the termination tools 3a and 3b leftward as indicated by arrow 15 into position for subsequent termination of the left connector piece L to the insulated wires. In addition, the pneumatic piston-and-cylinder drive 1b of the transporting unit 1 drives the carriage 1a back to the initial starting position. Thus, the right ends of the insulated wires, W1, W2 and W3 together with the right connector pieces R1, R2 and R3 terminated thereto are brought to the initial starting position. Fig. 8 shows that the pneumatic piston-and-cylinder drives 6b of the wire clamper 6 moves the clamping heads 6a to clamp the insulated wires W1, W2 and W3 as indicated by arrows 17. The pneumatic piston-and-cylinder drive 7b of the auxiliary support unit 7 raises its support head 7a to support the insulated wires W1, W2 and W3 as indicated by arrow 18. As indicated by arrow 19, the wire-supplying reel brake 5c of the wire supplying unit 5 is actuated to prevent the feeding of the insulated wires to permit the subsequent measuring operations. At the same time, the pneumatic piston-and-cylinder drive 4b of the lift 4 raises the nest 4a containing left connector piece L to the termination position, as indicated by arrow 20. Referring next to Fig. 9, the beginning of the measuring operation can be seen. The roll support 2a of the wire measuring unit 2 is lowered down to its lowermost position so that the rolls 2b contact and push down the intermediate points of the insulated wires W1, W2 and W3 to the lowest level. Thus, all of the insulated wires W1, W2 and W3 are pulled so that the length of wire between the left and right connector pieces L equals the length of the longest wire A1 to be formed (See Fig. 20). The level setting and controlling of the roll support are effected with the aid of a robot using a servomotor. In Fig. 20, the intermediate lengths extending from the inside wall of the left connector piece L to the inside walls of the right connector pieces R1, R2 and R3 are indicated by A1, A2 and A3. In the descriptions referring to Figs. 1 to 9 and subsequent drawings, however, for the sake of simplicity, the lengths A1, A2 and A3 of the insulated wires W1, W2 and W3 are given as the distances between the terminating positions at which the left and right connector pieces are terminated to the insulated wires. When the insulated wires are pulled downstream by pushing them down with wire measuring unit 2, the movable arms 5n rotate towards lateral stationary arm 5g to release the length of insulated wires which is retained between the guide rolls 5k and 5p, as indicated by arrow 22. At such time, pistons-and-cylinders 5c clamp the reels 5a so that no insulated wires are supplied from the reels 5a to the geometric wire retainers 5b. The pneumatic piston-and-cylinder 4c holds the nest 4a of the lift 4 at the elevated position. Referring to Fig. 10, selected wires W1 of all of the insulated wires W1, W2 and W3 are clamped by corresponding wire clampers 9 as indicated by arrow 24. Specifically, only the pneumatic piston-and-cylinders allotted to the selected insulated wires W1 are selectively actuated to clamp these insulated wires with their clamping heads 9a. In Fig. 11, the second longest lengths A2 of insulated wires W2 are measured. The roll support 2a is raised a predetermined distance to release the insulated wires. Because wires W2 and W3 are not clamped by wire clamps 9 and springs 5L are pulling the wires back upstream, the insulated wires W2 and W3 are pulled back by the spring-biased movable arms 5n of the geometric wire retainers 5 which permits these wires to follow the rising rolls 2b while the insulated wires W1 are clamped by selected wire clampers 9 to prevent the feeding-back of the insulated wires W1. Since the wire clamps 9 corresponding to wires W1 are isolating their respective wire retainers 5 from the wire measuring units 2, the piston-and-cylinders 5c corresponding to wires A1 are actuated to release the associated wire feeders 5 as indicated by arrow 26, thereby feeding predetermined lengths of insulated wires W1 to the geometric wire retainer as the spring-biased arms return to their initial raised position. At this point, insulated wires W2 and W3 have intermediate points positioned at the second lowest level and have a length corresponding to the length A2 between the opposite terminal connector pieces L and R2 in Fig. 20. Referring to Fig. 12, the wire clampers 9 allotted to the insulated wires W2 are actuated to clamp these wires. The spring-biased arms 5n allotted to the insulated wires W1 return to their initial positions to retain required lengths of insulated wires W1 for the subsequent measuring operation of the next harness. As shown in Fig. 13, the measuring of the third longest insulated wires W3 begins by raising the roll 2b a predetermined distance to the third lowest position. Since both the insulated wires W1 and W2 are clamped by the wire clampers 9 allotted to these wires, these insulated wires cannot be fed back. As a result, only wires W3 can be fed back upstream by the spring-biased movable arm 5n of the wire supply means 5 to permit wires W3 to follow roll 2b as it rises. By clamping wires W2 with wire clampers 9 and releasing their reels 5 by piston-and-cylinder 5c, wires W2 are fed to the geometric wire retainers 5 due to the spring bias of spring 5L. The distance the roll 2b is raised determines the length A3 of the third longest wire W3 as indicated in Fig. 20. The clampers 9 pertaining to the insulated wires W3 then clamp wires W3 as indicated at 30 in Fig. 14. The spring-biased movable arms 5n allotted to the insulated wires W2 return to their raised position to permit the geometric wire retainer 5 to retain enough of insulated wires W2 to meet the requirements of the next measuring operation. Referring to Fig. 15, left connector pieces are terminated to the left ends of all of the insulated wires W1, W2 and W3 by the termination tool 3b of the termination unit 3. Prior to the termination operation, the left ends of all the insulated wires W1, W2 and W3 are cut by lowering the piston of the pneumatic piston-and-cylinder 3d as indicated by arrow 31. The cutting and subsequent termination operations are effected by the lowering of the piston of the pneumatic piston-and-cylinder 3d. At that time, the pneumatic reel braking means 5c pertaining to the insulated wires W3 withdraws its piston (as indicated at 32) to permit the reels 5a to rotate freely which causes wires W3 to be fed to the geometric wire retainer 5b due to spring 5L. Referring to Fig. 16, the terminating unit 3, the auxiliary support mechanism 7, the measuring unit 2, and the wire clamper 6 return to their initial positions as indicated by arrows 33, 34, 35 and 36, respectively. Referring next to Fig. 17, the piston of the pneumatic piston-and-cylinder 3e of the termination unit 3 moves to the right as indicated by arrow 37 positioning the cutting and termination tools 3a and 3b in their initial positions. The left wire lift 8 raises its piston as indicated by arrow 38. Finally, the pneumatic support 4c associated with the left connector piece lift 4 withdraws its piston as indicated by arrow 39, thereby permitting the lowering of the nest 4a. Thus, the whole termination system is now in position for the subsequent measuring-and-termination operation. Referring to Fig. 18, a multi-circuit harness is completed. Such harness includes wires W1, W2 and W3 of required lengths A1, A2 and A3 having connector pieces L and R attached to their opposite ends. As shown in Fig. 20, the multi-circuit harness comprises nine insulated wires having a two-circuit connector piece R2 attached to the right ends of two insulated wires W2 of predetermined length A2, a four-circuit connector piece R3 attached to the right ends of four insulated wires W3 of predetermined length A3, and a three-circuit connector piece R1 attached to the right ends of three insulated wires W1 of predetermined length A1, and a nine-circuit connector piece L attached to the right ends of all of the insulated wires W1, W2 and W3 of predetermined lengths A1, A2 and A3. As may be understood from the above, a measuring-and-termination system according to the present invention can be advantageously used to produce harnesses each having wires of different lengths as required. For instance, a single multi-circuit connector piece can be connected to the left ends of a plurality of insulated wires whereas a similar multi-circuit connector piece can be connected to the right ends of the insulated wires, different multicircuit connector pieces can be connected to the opposite ends of a plurality of insulated wires. Fig. 21 shows one example of a harness having two connector pieces L1 and L2 and four connector pieces R1 and R2 attached to the opposite ends of ten insulated wires W1 and W2, with the longer and shorter ones being arranged somewhat alternately. The harnesses shown have connector pieces connected to opposite ends of the insulated wires. However, if desired, the left ends of the insulated wires may be left unterminated. At the time of removing the harnesses from the measuring-and-termination system, every harness is tested by a current conduction checker to determine whether electric current can flow from one to the other end of the harness, and defective harnesses if found, are rejected. Referring to Fig. 19, right connector pieces R are supplied to the nest of the carriage 1a of the transporting unit 1 for the subsequent termination operation, and left connector pieces L are supplied to the nest 4a of the connector piece lift 4. Then, the measuring-and-termination system returns to the position as shown in Fig. 1, starting the subsequent measuring-and-termination operation.

Claims: An apparatus for making electrical harnesses, each harness including a first electrical connector (R) having terminals of the insulation piercing type, a plurality of wires (W1, W2, W3) connected at one end to said first connector and said wires being of at least two different lengths, said apparatus including: a wire feeding path; a first station at which said first connector is loaded onto a first connector nest; a second station located along said wire feeding path and at which said wires are connected to said first connector; a carriage (1) for moving said first connector nest between said first station and said second station; and moving it back to the first station after the wires are connected thereto a plurality of wire feeding reels (5a), each for supplying an individual wire along said wire feeding path; a termination unit (3) located at said second station for simultaneously displacing one end of each wire in a direction perpendicular to its axis and into one of said terminals to establish an electrical and mechanical connection therebetween; a wire measuring unit (2) positioned downstream of said second station for increasing the length of wire between the first connector connected to said wires and said second station; a wire supplying (5) unit having a plurality of wire retaining assemblies (5b) located upstream of said second station and along said wire feeding path for providing a biasing force in upstream direction on said wires, said plurality corresponding in number to said plurality of wires to be connected; and a plurality of individually, selectively actuatable wire clamp mechanisms (9), each being located between one of said wire retaining assemblies (5b) and said second station; and wherein: said wire measuring unit (2) comprising a looper assembly (2a, 2b) for engaging wires at said position while one end of each of said wires is fixed in said first connector and pulling the wires along said wire feeding path past said second station to increase the length of wire between said first connector and said second station; and each of said wire retaining assemblies (5b) having an inlet and an outlet along said wire feeding path, a first section (5g) having first and second spaced apart pulleys (5k, 5h) rotatably mounted thereon and a second movable member (5n) mounted for pivotal movement relative to said first section, said second movable member having a third rotatable pulley (5p) mounted thereon and being pivotable between a first position (5t) at which said third rotatable pulley is located relatively proximal to said first section and a second position (5m) at which said third rotatable pulley is located relatively distal from said first section, each said wire retaining assembliy (5b) further including a spring member (5L) to bias said second member toward said second position in order to create a force biasing said wire in a direction upstream along said wire feeding path, whereby a wire enters said inlet, contacts said first pulley, is looped around said second pulley, is looped around said third pulley, contacts said second pulley and exits said wire retaining assembly (5b) through said outlet. The apparatus of claim 1 wherein said first station is located downstream of said second station along said wire feeding path, and said looper assembly is located between said first and second stations. The apparatus of claim 2 further including a first termination tool (3a) moveable in a direction perpendicular to said wire feeding path for connecting the first connector to one end of said wires, and a second termination tool (3b) moveable in a direction perpendicular to said wire feeding path for connecting a second connector to said wires, said first and second termination tools also being moveable in a direction generally parallel to said wire feeding path. The apparatus of claim 2 further comprising a clamp mechanism (6) located between said looper assembly and said first station for clamping each wire connected to said first electrical connector in order to reduce the strain on the connection of said wires to the terminals of said first connector upon engagement of said wires by said looper assembly. The apparatus of claim 4 further including a support member (7) located between said second station and said looper assembly to guide said wires during engagement of said wires by said looper assembly. The apparatus of claim 4 further including a wire lift mechanism (8) located between said second station and said individually, selectively actuatable wire clamp mechanisms to raise and lower the ends of said wires relative to said first connector nest when said nest is positioned at said second station. The apparatus of claim I wherein each said wire feeding reel is operatively associated with a drive motor (5d) for feeding wire to one of said wire retaining assemblies (5b), and a brake assembly (5g, 5r, 5s) to start and stop feeding of said wire by said motor, each said brake assembly being controlled by movement of said second moveable member. A method of manufacturing an electrical harness, each harness including a first electrical connector (R) having terminals of the insulation piercing type, a plurality of wires connected at one end to said first connector and said wires being of at least two different lengths, said method comprising the steps of: providing a wire feeding path; providing a plurality of individual wires along said wire feeding path with one end of each being located at a second station positioned along said wire feeding path; feeding said first electrical connector into a first connector nest (1a); moving said first connector nest and said first connector to said second station; simultaneously displacing one end of each wire in a direction perpendicular to its axis and into one of said terminals of said first connector to establish an electrical and mechanical connection therebetween; moving said first connector and said wires connected thereto to a first station; securing each said wire upstream of said second station between a wire reel (5a) and a wire retaining assembly (5b), said wire retaining assembly (5b) being located downstream of said wire reel, each of said wire retaining assemblies (5b) having an inlet and an outlet along said wire feeding path, a first section (5g) having first and second spaced apart pulleys (5k, 5h) rotatably mounted thereon and a second movable member (5n) mounted for pivotal movement relative to said first section, said second movable member having a third rotatable pulley (5p) mounted thereon and being pivotable between a first position (5t) at which said third rotatable pulley is located relatively proximal to said first section and a second position (5m) at which said third rotatable pulley is located relatively distal from said first section, each said wire retaining assembly (5b) further including a spring member (5L) to bias said second member toward said second position in order to create a force biasing said wire in a direction upstream along said wire feeding path, whereby a wire enters said inlet, contacts said first pulley, is looped around said second pulley, is looped around said third pulley, contacts said second pulley and exits said wire retaining assembly (5b) through said outlet; moving a looper assembly (2a,2b) downward from a non-engagement position above said wire feeding path to a full engagement position into and past the wire feeding path to engage said wires at a position intermediate said first connector and said second station to pull said wires past said second station to increase the length of wire between the first connector connected to said wires and said second station, said pulling of said wires past said second station causing said second movable member to pivot from said second position to said first position and thus decrease the length of wire retained in said wire retaining assembly (5b) between said second and third pulleys; actuating certain of a plurality of individually, selectively actuatable wire clamp mechanisms (9), each being located between one of said wire retaining assemblies (5b) and said second station; moving said looper assembly upward from said full engagement position toward said non-engagement position whereby said wires that are not engaged by said wire clamp mechanisms are drawn back upstream by said spring member of each said wire retaining assembly (5b) so that said not engaged wires follow said looper assembly upward and said second movable member pivots from said first position towards said second position and thus increases the length of wire retained in said wire retaining assembly (5b) between said second and third pulleys; repeating said steps of actuating said wire clamps and moving said looper upward until all of said wire clamps are actuated; and cutting the upstream ends of said wires at said second station to fabricate a harness having wires of at least two different lengths. The method of claim 8 further including the step of simultaneously displacing one end of a plurality of said wires in a direction perpendicular to their axes and into respective insulation piercing type terminals of a second connector to establish an electrical and mechanical connection therebetween. The method of claim 9 wherein the step of simultaneous displacement step of the wires of the first connector is carried out by a first termination tool (3a) moveable in a direction perpendicular to said wire feeding path, said step of simultaneous displacement step of the wires of the second connector is carried out by a second termination tool (3b) moveable in a direction perpendicular to said wire feeding path, and said first and second termination tools are moved in a direction generally parallel to said wire feeding path between said simultaneous displacement steps. The method of claim 8 further including the steps of clamping each wire connected to said first electrical connector between said looper assembly and said first station for in order to reduce the strain on the connection of said wires to the terminals of said first connector upon engagement of said wires by said looper assembly, supporting said wires between said second station and said looper assembly to guide said wires during engagement of said wires by said looper assembly.

Inventors: ASAOKA AKIHIRO, ISHIWATA YOSHIO, ASAOKA, AKIHIRO, ISHIWATA, YOSHIO
Applicants: MOLEX INC, MOLEX INCORPORATED
Application year: 1992
Main classification: H01R43
IPC codes: H01R43, H01B13