APPARATUS FOR MANUFACTURING ELECTRICAL HARNESSES

Abstract: Apparatus for making electrical harnesses comprising wires and electrical connectors has a wire feed path (W) extending axially therethrough, a connector attaching device (11) comprising a co-operating assembling punch (21) and die (22) pair disposed on opposite sides of the wire feed path (W), and a wire cutting blade (23) located adjacent to the punch (21) and die (22) pair. A first chuck (12) is reciprocally movable along the wire feed path (W) and pulls out the wires in its advancing movement to a desired length for the electrical harness; a second chuck (13) holds the supplied wires laterally at equal intervals, guides them to the connec­ tor attaching device (11) and is reciprocally movable in a small range to align the free ends of the wires. An insulation covering stripping device is mounted on the second chuck (13) and, when the wires have been pulled out by the first chuck (12) to a desired length from the connector attaching position, is operated to slit and remove the insulation covering at the free end of each wire, the connector attaching device (11) then being operated to cut the wires to a desired length, and attach a connector (3) to the tail end of the wires.

Description: The invention relates to apparatus for manufacturing electrical harnesses automatically, and more particularly, to fully automatic apparatus for manufacturing electrical harnesses of the kind which comprise a plurality of wires cut to desired lengths and a multi-contact type connector attached to the wires at one end thereof. Recently semi-automatic or fully automatic apparatus for producing such harnesses has been developed, typical examples of which are disclosed in Japanese Patent Kokai (unexamined Publication) No. 58(1983)-145080, U.S. Patent No. 4,136,440 and U.S. Patent No. 4,310,967. The finished electrical harness has its connector-free end covered with an insulation covering, which must be removed so as to enable the electrical conductors to be connected to circuits and instruments. To remove the insulation covering automatically, a stripping device is additionally provided in the system for making electrical harnesses. Under the conventional system, however, the stripping device is located adjacent to the connector assembling device, and the stripping process is carried out independently of the connector attaching process, the wire length measuring process and others. If full automation in making electrical harnesses is to be achieved, it is required for the stripping process to be carried out at the same time as the wire length measuring process is performed since this can considerably shorten the operation time. According to the invention there is provided apparatus for making electrical harnesses comprising wires and electrical connectors, the apparatus comprising: a wire feed path extending substantially horizontally and axially of the apparatus; a connector attaching device comprising a co-operating assembling punch and die pair disposed on opposite sides of the wire feed path; a wire cutting blade located adjacent to the punch and die pair; a connector supplying device for supplying connectors to the assembling die; a first chuck reciprocally movable along the wire feed path for pulling out the wires in an advancing movement for a distance corresponding to a desired length of the electrical harness; and a second chuck for holding the supplied wires laterally at dual intervals, and guiding the wires to the connector attaching device along the wire feed path, the second chuck being reciprocally movable in order to align the free ends of the wires; and an insulation covering stripping device mounted on the first chuck; the apparatus being movable in a manner such that: wires supplied to the connector attaching device are pulled out by the first chuck to a desired length from the connector attaching position; the insulation covering stripping device is operated during the operation of the first chuck to remove the insulation covering on the free end of each wire; and the connector attaching device is operated to cause the wires to be cut by the wire cutting blade to a desired length, and to attach the connectors to the tail ends of the wires. The apparatus of the invention can be fully automatic and includes a stripping device provided in the wire length measuring device so that the wire length measuring process and the insulation covering stripping process can be simultaneously carried out. The invention is diagrammatically illustrated by way of example with reference to the accompanying drawings, in which:- Figure 1 is a schematic front view showing one embodiment of apparatus for making electrical harnesses according to the invention; Figure 2 is a vertical cross-section on a larger scale showing a main section of a connector attaching device shown in Figure 1; Figures 3 and 4 are cross-sectional views on a larger scale showing the operating states of the main section shown in Figure 2; Figure 5 is a partially cross-sectional view showing a first movable chuck shown in Figure 1; Figures 6 and 7 are diagrammatic views showing the operating states of a stripping device mounted on the chuck of Figure 5; Figures 8(a) to (f) are diagrammatic views showing the operating steps of a connector attaching operation; Figures 9(a) and (b) are diagrammatic views showing the operating steps of a modified connector attaching operation; and Figures 10 to 12 are schematic views showing finished electrical harnesses. Referring to the drawings and firstly to Figure 1, apparatus for manufacturing electrical harnesses includes a wire supplying device 10 which supplies wires 2 horizontally in parallel by means of a bundling device 5, the wires 2 being supplied along a wire feed path W through a straightener 6 and a feed roller 7. A connector attaching device 11 is provided for attaching connectors 3 to the ends of the wires 2 by means of a punch 21 and a die 22 disposed on opposite sides of the wire feed path W, the punch and die having a cutting blade 23 located adjacent thereto. A connector supplying device (not shown) supplies connectors to the die 22 one by one. A first movable chuck 12 carries the wires 2 supplied to the connector attaching device 11 along the wire feed path W for a desired distance, whereby the desired length of the wires 2 is determined, and a second movable chuck 13 holds the wires 2 horizontally at equal intervals in parallel and guides the wires 2 to the connector assembling device 11 at which the second chuck 13 adjusts the positions of the wire ends. The second chuck 13 reciprocally moves in a predetermined relatively small range. The apparatus further includes a third movable chuck 14 provided between the second chuck 13 and the connector attaching device 11 and movable in a predetermined range along the wire feed path W. A device for determining the lengths of insulation covering to be stripped, hereinafter referred to as the stripping length varying device 15, is located between the second and third chucks 13 and 14. A stripping device 17, for removing the insulation covering of the wires 2, is mounted on the first chuck 12. The connector supplying device includes a conventional hopper feeder and magazine, the description of which will be omitted for simplicity. The punch 21 is mounted on a slider 25 which can be raised and lowered by means of a pneumatic cylinder 24, and is lowered from the raised position shown in Figure 2 to the lowered position shown in Figures 3 and 4 to cause the connectors to be attached to the wire ends. The cutting blade 23 is also mounted on the slider 25, and is operated by means of a pneumatic cylinder 26 fixed to the slider 25, independently of the punch 21. The cutting blade 23 cuts the wires in cooperation with a cutting die 27 at the preparatory position for connector attaching. In addition, the slider 25 has a wire chuck 28 for holding the wires at the moment of connector attaching, and a wire guide 29. The die 22 is mounted on a slider 30, which can be raised and lowered step by step by means of a first pneumatic cylinder 31 and a second cylinder 32 coupled to the first cylinder 31 through a joint 33 in such a manner that they can move together. The die 22 moves together with the slider 30 and, in operation, the die 22 is raised from the position shown in Figure 2 together with the slider 30 by means of the first pneumatic cylinder 31 until it reaches the preparatory position for connector attaching shown in Figure 3. From the preparatory position it is further raised to the position shown in Figure 4 where the connectors are attached to the wire ends. A connector presser 34 is provided at the release side of the die 22, the connector presser 34 securing the connector 3 under the pressure of a spring (not shown). The connector presser 34 has a further wire chuck 35 located adjacent thereto, which mates with the wire chuck 28 The wire chuck 35 is operated by means of a pneumatic cylinder 36 mounted on the slider 30, independently of the die 22; it is raised from the preparatory position shown in Figure 3, and by working in association with the wire chuck 28, grips the group of wires 2A which have been pulled out to a desired length by the first chuck 12. As shown in Figure 5, the first chuck 12 includes a movable frame 40, and two pneumatic cylinders 41, 42 fixed to the movable frame 40. The two pneumatic cylinders 41 and 42 are coaxially provided and the piston rod 44 of the cylinder 42 passes through a piston rod 43 of the cylinder 41. A pair of arms 45 are pivotally attached to the movable frame 40 at their middle portions by pivot pins 46. Each arm 45 is provided with a chuck tooth 47 at its free end, and with a link 48 at its tail end, the link 48 being connected to the piston rod 43 to that the chuck teeth 47 can be opened and closed by operation of the pneumatic cylinder 41. The movable frame 40 can be reciprocally moved along the wire feed path W. The stripping device 17 mounted on the first chuck 12 includes a pair of sliders 50, and a stripping blade 51 fixed at the free end of each slider 50. Each slider 50 is slidably engaged in a dovetail groove 52 provided in an inner side of a respective one of the arms 45, and links 53 fixed to inner end portions of the sliders 50 are coupled to a connecting member 54 mounted on the free end of the piston rod 44. The sliders 50 can thus be reciprocally moved along the dovetail grooves 52 by means of the pneumatic cylinder 42. The sliders 50 move with the arms 45 so that as the chuck teeth 47 open or close the stripping blades 51 are opened and closed. The second chuck 13 can be opened and closed by means of a pneumatic cylinder 55, and can be reciprocally moved along the wire feed path W between the full line position and the dotted line position shown in Figure 1, a relatively small range, by a pneumatic cylinder 56. The third chuck 14 can be opened and closed by means of a pneumatic cylinder 58 and is movable along the wire feed path W as shown in Figure 1 by a pneumatic cylidner 59. Reference numerals 57 and 60 denote wire guides. The stripping length varying device 15 includes a plurality of varying plates 61 which are arranged laterally in such a manner that one plate corresponds to one wire and which are individually capable of ascending and descending; a pneumatic cylinder 62 for moving the varying plates 61 up and down, and a pair of guide rollers 63, the pair of guide rollers 63 and the varying plate 61 being disposed on opposite respective sides of the wire feed path W. The reference numeral 64 denotes a straightener located adjacent to the stripping length varying device 15, so as to straighten up the wires bent by the varying plates 61. The wire length varying device 16 includes a plurality of varying plates 65; a pneumatic cylinder 66 for moving the varying plates 65 up and down, and guide rollers 67, which are provided on a carrier 68 which can be moved up and down by means of a pneumatic cylinder 69. This enables the guide rollers 67 to descend below the path of the first chuck 12, thereby allowing the first chuck 12 to pass safely above the rollers 67. An example of the operation will be described with reference to Figure 8: Figure 8 shows the steps of attaching the connectors to the wires. In Figure 8(a) the wires 2 have been supplied to the connector attaching device 11 by means of the feed roller 7 and by way of the second and third chucks 13 and 14. At first the wires 2 are pulled backward by the chuck 13 so as to align the free ends thereof with a desired point R. At this stage the first chuck 12 is shifted to a position under the punch 21. The second chuck 13 is kept open, and the third chuck 14, while gripping the wires 2, is caused to advance for a distance corresponding to the longest insulation covering. (Figure 8(b)) Then as shown in Figure 8(c), the wires 2 are released from the third chuck 14, and are gripped by the second chuck 13. At this stage the stripping length varying device 15 is operated, thereby causing the individual varying plates 61 to descend so as to bulge the wires 2 downward. As a result, the free ends of the wires are withdrawn by different lengths according to the amount by which they have been bulged downwardly. Then, the first chuck 12 is operated, and grips the free ends of the wires 2 by means of the chuck teeth 47. At the same time the stripping blades 51 slit the insulation coverings of the wires. (Figure 8(d)) The first chuck 12 is advanced along the wire feed path W to pull the wires to a desired length. During the pulling travel the stripping device 17 is operated to move the stripping blades 51 way from the chuck teeth 47, thereby stripping the insulation covering off the conductor. (Figure 8(e)) As best shown in Figures 6 and 7, the lengths of the stripped conductors vary, which is derived from the fact that the position of the top ends of the wires 2 are differentiated in accordance with the lengths to be stripped. Then, the connector attaching device 11 is operated: At the preparatory position shown in Figure 3 the wire cutting blade 23 is lowered to cut the wires 2 in co-operation with the die 27, and the wires are pinched by the second chuck 13 until the cut ends thereof are positioned at the point R. Then the assembling die 22 is raised up to the connector assembling position shown in Figure 4, and the connector 3 is attached to the cut ends of the advancing wires 2A. (Figure 8(f)) Then the assembling punch 21 is raised, and the assembling die 22 is lowered, thereby allowing the connector 3 attached to the wire ends to be released from the die 22. The wires 2A are further withdrawn by the first chuck 12, and discharged out of the apparatus. The operation can then be repeated. As shown in Figure 10, a harness 9 has its wires 2A cut to predetermined lengths, and provided with one connector 3 at one end, with the other ends being free from a connector and having varying lengths of stripped conductors. A harness 9₁ shown in Figure 11 can be formed by slackening the wires by means of the varying plates 65 in the manner shown in Figure 9(a) and (b). A harness 9₂ shown in Figure 12 can be formed by using neither of the stripping length varying device 15 and the wire length varying device 16.

Claims: Apparatus for making electrical harnesses comprising wires and electrical connectors, the apparatus comprising: a wire feed path (W) extending substantially horizontally and axially of the apparatus; a connector attaching device (11) comprising a co-operating assembling punch (21) and die (22) pair disposed on opposite sides of the wire feed path (W); a wire cutting blade (23) located adjacent to the punch (21) and die (22) pair; a connector supplying device for supplying connectors (3) to the assembling die (22); a first chuck (12) reciprocally movable along the wire feed path (W) for pulling out the wires (2) in an advancing movement for a distance corresponding to a desired length of the electrical harness; and a second chuck (13) for holding the supplied wires laterally at equal intervals, and guiding the wires to the connector attaching device (11) along the wire feed path (W), the second chuck (13) being reciprocally movable in order to align the free ends of the wires (2); and an insulation covering stripping device (17) mounted on the first chuck (12); the apparatus being movable in a manner such that: wires supplied to the connector attaching device (11) are pulled out by the first chuck (12) to a desired length from the connector attaching position; the insulation covering stripping device (17) is operated during the operation of the first chuck (12) to remove the insulation covering on the free end of each wire; and the connector attaching device (11) is operated to cause the wires to be cut by the wire cutting blade (23) to a desired length, and to attach the connectors (3) to the tail ends of the wires (2A). Apparatus according to claim 1, further comprising a wire length varying device (16) located between the first chuck (12) and the connector attaching device (11) and adjacent to the connector attaching device (11), to enable the lengths of the wires of the harness to be varied with respect to one another. Apparatus according to claim 1 or claim 2, further comprising a third chuck (14) movable over a small range and located between the connector attaching device (11) and the second chuck (13), the third chuck (14) being provided to adjust the length of the insulation covering to be stripped, and a stripping varying device (15) located between the second and third chucks (13) and (14) to slacken the individual wires so that the lengths of their insulation covering stripped off vary with respect to one another.

Inventors: MATSU'URA, YUKITO, OKAZAKI, TAKASHI, SAIJO, YOSHIHIRO
Applicants: NIPPON ACCHAKUTANSHI SEIZO KABUSHIKI KAISHA
Application year: 1985
Main classification: H01R43
IPC codes: H01R43, H01B13