GB2273895A - Method of manufacturing a wire harness - Google Patents

Abstract

The present invention is directed to a method of manufacturing a wiring harness comprising the steps of manufacturing wire units (W1, W2) respectively formed of single-line electric wires, inserting the manufactured wire units into predetermined connector housings (6 to 10) to manufacture a predetermined number of subassembly circuits having no junction, collecting the subassembly circuits in the finished configuration, and further connecting necessary electric wires among the electric wires constituting each of the collected subassembly circuits to each other in a short-circuited manner using a press-connecting joint connector (J/C). <IMAGE>

Description

DESCRIPTION METHOD OF MANUFACTURING A WIRING HARNESS The present invention relates generally to a method of manufacturing a wiring harness, and more particularly, to an improvement in the manufacturing processes in a case where a wiring harness is manufactured using a press-connecting joint connector, that is, a "press-connecting joint terminal".

A wiring harness of such construction that electric wires are connected to each other using a press-connecting joint connector has been known among wiring harnesses incorporated in automobiles, copying machines or the like.

For example, Japanese Patent Examined Publication No.

37672/1979 discloses one example of the press-connecting joint connector. In addition, a wiring harness using such a pressconnecting joint connector is disclosed in Japanese Utility Model Application Serial No. 60-944 (see Japanese Utility Model Laid-Open Publication No. 117465/1986) and Japanese Patent Laid-Open Publication No. 192209/1983.

As shown in Fig. 1, the conventional wiring harness using the press-connected joint connector has a construction in which electric equipments 101, 102, 103, and 104 are connected by wires 105, 106, and 107. Wires 105, 106, and 107 have intermediate portions which form a longitudinally located collective bundle 108 at which a press-connected joint connector 110 connects the wires 105, 106, and 107 in a shortcircuited manner.

As shown in Fig. 2, also known is a wiring harness so constructed that electric wires 205, 206 and 207 are provided for electrical equipments 201, 202, 203 and 204 and a ground terminal 209, one ends of the electric wires 205, 206 and 207 are, respectively, connected to the electrical equipments 201, 202, 203 and 204, while the other ends thereof are collected in a common joint connector 210 and are connected to each other in a short-circuited manner by a joint bus bar 211.

Each of the wiring harnesses in the prior art is a relatively simple circuit, and a press-connecting type joint terminal or the like is used for connecting all electric wires constituting the circuit to each other in a short-circuited manner.

On the other hand, to give the latest instance of wiring harnesses for automobiles, there are few wiring harnesses having a simple circuit arrangement as disclosed in the foregoing prior art. The number of wiring harnesses having a very complicated and large-scale circuit arrangement in which, for example, 400 to 500 circuits are integrated has been increased. The reason for this is that many recent automobiles are provided with various electrical equipment such as an air conditioner, a power window, an electromagnetic door lock, a power mirror adjuster and a power sheet in addition to basic electrical equipment such as a windshield wiper and a car radio.

It is impossible to manufacture a wiring harness having such a large-scale circuit arrangement in one operation.

Therefore, the following process has been employed: manufacturing small number of subassembly circuits, for example, 5 to 25, which are easily memorized and manufactured by a worker; and then collecting a predetermined number of subassembly circuits, that is, manufacturing the wiring harness in the final configuration.

Description is made more concretely with reference to Figs. 3A to 3D. For convenience of description and illustration, the number of circuits shown in Figs. 3A to 3D is much smaller than the actual number of circuits. Figs. 3A to 3D do not show one example of the actual circuit arrangement.

Figs. 3A to 3D are diagrams ilJustrating the manufacturing procedure of the conventional wiring harness.

In the manufacturing processes of the conventional wiring harness, there are steps of: measuring and cutting processes for cutting an electric wire to a predetermined length; a stripping process for stripping insulating sheaths at both ends of the electric wire measured and cut to expose conductors at both ends of the electric wire; and a terminal crimping process for crimping terminal fittings to the exposed conductors at both ends of the electric wire (see Fig. 3A).

Electric wires which should be spliced to each other are then subjected to a splice process. In the splice process, an intermediate portion of an electric wire measured and cut is stripped, one end of an electric wire to be connected is crimped while the other end is connected to the stripped intermediate portion by a joint terminal, and an insulating tape is wound around a junction of the electric wires connected to each other (see Fig. 3B).

Subassembly circuits are then formed. Each of the subassembly circuits is formed by inserting the terminals crimped to one ends of electric wires into predetermined connector housings. In many cases the subassembly circuits have been conventionally formed manually by a worker, so that the subassembly circuits are designed in units whose number is easily memorized and manufactured by the worker: 5 to 25 such units.

As shown in Fig. 3C, subassembly circuits thus formed include sometimes a subassembly circuit Y1 having a junction and sometimes a subassembly circuit X1 having no junction. In the example shown in Fig. 3C, the subassembly circuit Y1 having a junction comprises two electric wires having both ends being respectively inserted into connector housings A and B. Two branch electric wires are spliced to one of the electric wires. An end of the branch electric wire is a socalled bulk terminal, which is not inserted into a connector housing at this stage.

As shown in Fig. 3D, the subassembly circuits X1 and Y1 are then collected in the final configuration. In the assembling process, the bulk terminals in the subassembly circuit Y1 are respectively inserted into connector housings C and D of the subassembly circuit X1.

The foregoing processes of manufacturing the conventional wiring harness have the following disadvantages.

(1) Since the splice process is carried out manually by a worker for each lot, work time required for the splice process is longer than that required for the other processes, resulting in poor manufacturing efficiency as a whole.

(2) Before the subassembly circuits are formed, the splice process is carried out. Accordingly, the electric wires for forming each of the subassembly circuits include electric wires having a junction, so that the electric wires are often tangled at the time of forming the subassembly circuits, particularly when the one electric wire with a junction is drawn from the wires which are splice processed and stocked as a lot. Such tangles of the electric wires disturb the smooth manufacturing of subassembly circuits.

(3) The tangles of the electric wires also occur even when the predetermined number of the subassembly circuits are assembled, because some subassembly circuits include junctions.

The problems (1) and (2) among three may be solved by applying the construction of the wiring harness using the press-connecting joint connector in the prior art previously described: the press-connecting joint connector may joint the subassembly circuit.

However, the subassembly circuits do not always have the construction using the press-connecting joint connector in the prior art. The electric wires in many subassembly -circuits having junctions are not always commonly jointed to each other. Rather, branch electric wires are often connected to a particular electric wire by the connectors, as in the foregoing subassembly circuit Y1 shown in Fig. 3B. Therefore, the problems (1) and (2) are not solved with respect to all the subassembly circuits even by applying the construction of the wiring harness using the press-connecting joint connector in the prior art.

Furthermore, the foregoing problem (3) cannot be solved even by applying the construction of the wiring harness using the press-connecting joint connector in the prior art.

The reason for this is that the wiring harness in the prior art merely covers a subassembly circuit such as a grand circuit in which electric wires can commonly be connected to each other in a short-circuited manner, not a composite circuit comprising a lot of circuits which should, respectively, connected to each other in order to form plural systems. In other words, the wiring harness in the prior art is just a subassembly circuit to which the present invention pertains and comprising relatively small number of circuits.

Consequently, what is really needed in view of the foregoing problems, is a method of manufacturing a wiring harness efficiently as a whole that includes the manufacturing processes of first manufacturing subassembly circuits suitable for the recent operation and then collecting the subassembly circuits to form an assembly circuit.

Furthermore, what is also really needed is a method of manufacturing a wiring harness suitable for automation of the manufacture using an automatic manufacturing machine.

The present invention is directed to a method of manufacturing a wiring harness that satisfies the foregoing needs.

In the present invention, subassembly circuits are manufactured before assembling a wiring harness. Each of the subassembly circuits is a circuit having no junction at intermediate portions of electric wires constituting the subassembly circuit. The present invention includes a process for connecting the subassembly circuits having no junction to each other in a short-circuited manner by a pressconnecting joint connector.

In accordance with the present invention, there is provided a method of manufacturing a wiring harness, comprising the steps of: manufacturing a plurality of wire units required to form a predetermined number of subassembly circuits by carrying out a measuring and cutting process for cutting an electric wire to a predetermined length, a stripping process for striping insulating sheaths at both ends of the electric wire measured and cut to expose conductors, and a terminal crimping process for crimping terminal fittings to the exposed conductors at both ends of the electric wire; manufacturing a predetermined number of subassembly circuits having no junction by respectively inserting the terminal fittings on the plurality of wire units into predetermined connector housings; and collecting the predetermined number of subassembly circuits thus manufactured in the finished configuration and connecting the electric wires which should be electrically connected to each other among the electric wires constituting each of the subassembly circuits in a short-circuited manner using a press-connecting joint connector at that point in time.

In the present invention, a plurality of wire units required to manufacture the subassembly circuits are first manufactured. Each of the wire units is formed by a measuring and cutting process, a stripping process and a terminal crimping process. The wire units formed are respectively formed of single-line electric wires having no junction.

Therefore, the wire units respectively formed of single-line electric wires may be respectively inserted into connector housings in manufacturing the subassembly circuits, so that the electric wires are not tangled. A predetermined number of subassembly circuits manufactured are collected. All of the subassembly circuits before assembling have no junction, so that the subassembly circuits are not tangled at the time of assembling. At the time of assembling, electric wires which should be electrically connected to each other out of the electric wires constituting each of the subassembly circuits are connected to each other in a short-circuited manner by the press-connecting joint connector.The electric wires are not connected to each other until the time of assembling, that is, the tie of the final process out of the manufacturing processes of the wiring harness. Moreover, the electric wires are connected to each other using the press-connecting joint connector, which is possible simply and in a short time. The advantage of the present invention is that a connecting process need not be carried out until assembling, so that the subassembly circuits can be easily manufactured, thereby to make it possible to increase the efficiency of the manufacturing operation as a whole. Particularly, the subassembly circuits are constituted by the wire units respectively formed of single-line electric wires, so that the manufacturing method can easily be adapted to the mechanized production.

Furthermore, in a preferred embodiment of the present invention, a press-connecting pressing machine is used when electric wires which should be electrically connected to each other at the time of assembling are connected to each other in a short-circuited manner by a press-connecting joint connector, so that a worker can mount the press-connecting joint connector to the machine easily and without any burden.

In a more preferred embodiment of the present invention, subassembly circuits can be manufactured in units of subassembly circuits which are easily mechanized or shared.

Therefore, it is possible to easily manufacture subassembly circuits which can be shared among many types of circuits.

In a still more preferred embodiment, when subassembly circuits are mechanized, electric wires which are connected to each other by a press-connecting joint connector at the time of assembling are laid out so as to form in a loop shape, thereby to make it possible to easily connect the electric wires to each other in a short-circuited manner by a pressconnecting joint connecter at the time of assembling.

In a further preferred embodiment of the present invention, subassembly circuits can be formed using an automated device. Therefore, the manual operation can merely be a final assembling process, thereby to make it possible to increase the efficiency of the method of manufacturing a wiring harness.

By way of example only, specific embodiments of the present invention will now be described with reference to the accompanying drawings in which: Fig. 1 is a diagram showing one example of a wiring harness using a press-connecting joint connector in the prior art; Fig. 2 is a diagram showing another example of a wiring harness using a press-connecting joint connector in the prior art; Figs. 3A to 3D are diagrams illustrating a method of manufacturing the conventional wiring harness; Figs. 4A to 4D are diagrams illustrating a method of manufacturing a wiring harness according to one embodiment of the present invention; Fig. 5 is an illustration showing the construction of the conventional subassembly circuit X1; Fig. 6 is an illustration showing the construction of the conventional subassembly circuit Y1;; Fig. 7 is an illustration showing the construction of an assembly circuit formed by collecting the conventional subassembly circuits X1 and Y1; Fig. 8 is an illustration showing the construction of a subassembly circuit X2 manufactured by the manufacturing method according to one embodiment of the present invention; Fig. 9 is an illustration showing the construction of a subassembly circuit Y2 manufactured by the manufacturing method according to one embodiment of the present invention; Fig. 10 is an illustration showing the construction of an assembly circuit formed by collecting the subassembly circuits X2 and Y2 manufactured by the manufacturing method according to one embodiment of the present invention; ; Fig. 11 is a diagram showing an advantage in manufacturing the wiring harness by the manufacturing method according to one embodiment of the present invention, in contrast to the conventional manufacturing method; Figs. 12A to 12B are diagrams showing an advantage on the construction of the wiring harness in employing the manufacturing method according to one embodiment of the present invention, in contrast to the present manufacturing method; Fig. 13 is a diagram showing an example of the construction of a drawing board for work required for assembling in the manufacturing method according to one embodiment of the present invention; and Fig. 14 is a perspective view showing one example of a press-connecting pressing machine 30 disposed in a pressing space 23 and one example of a press-connecting joint connector stand 24.

Referring now to Fig. 4, description is made of the outline of the embodiment. First, there are steps of: a measuring and cutting process for cutting an electric wire to a predetermined length; a stripping process for stripping insulating sheaths at both ends of the electric wire measured and cut to expose conductors at both ends of the electric wire; and a terminal crimping process for crimping terminal fittings against the exposed conductors at both ends of the electric wire (see Fig. 4A).

A plurality of wire units thus formed are required so as to form subassembly circuits, and the wire units are respectively formed of single-line electric wires.

The plurality of wire units respectively formed of single-line electric wires are not subjected to a splice process as in the conventional one, but the manufacture of the subassembly circuits is immediately started (see Fig. 4B).

The subassembly circuits are formed by respectively inserting the terminal fittings on the plurality of wire units into predetermined connector housings. For example, both ends of each of given two electric wires are respectively inserted into connector housings A and B, thereby forming a subassembly circuit X2. In addition, respective one ends of given two wire units are respectively inserted into connector housings C and D, the respective other ends thereof are both inserted into a connector housing E, and both ends of another one wire unit are respectively inserted into the connector housings C and D, thereby forming a subassembly circuit Y2.

The subassembly circuits X2 and Y2 thus formed have no junction, as shown in Fig. 4B.

A predetermined number of subassembly circuits are collected in the finished configuration to from an assembly circuit (see Fig. 4C). In the assembling, the subassembly circuits X2 and Y2, for example, are collected in the finished configuration, and electric wires which should be electrically connected to each other among the electric wires constituting the subassembly circuits are electrically connected to each other in a short-circuited manner by a press-connecting joint connector J/C. The great advantage of the embodiment is that the subassembly circuits are thus connected to each other in the final stage of the manufacture of the wiring harness, that is, the assembling.

If the foregoing method of manufacturing the wiring harness according to one embodiment of the present invention is used, the electric wire measured and cut is basically a single-line electric wire until the time of assembling, so that the connecting process need not be provided during the manufacturing processes, thereby preventing the degradation of the workability by the splice process. In addition, the manufacture of the subassembly circuit including the measuring and cutting process, the stripping process and the terminal crimping process can be easily achieved using an automated machine, as described in detail later.

Referring now to Figs. 5 to 10, description is made by taking as an example a more specific circuit close to the actual product. It would be noted that also in Figs. 5 to 10, the number of subassembly circuits which are collected is made smaller, as compared with the actual circuit for convenience of illustration.

Figs. 5, 6 and 7 out of Figs. 5 to 10 show the conventional subassembly circuits X1 and Y1 and an assembly circuit obtained by collecting the subassembly circuits which are illustrated for comparison. On the other hand, Figs. 8, 9 and 10 show the subassembly circuits X2 and Y2 manufactured by the manufacturing method according to one embodiment of the present invention and an assembly circuit obtained by collecting the subassembly circuits X2 and Y2 which are illustrated in contrast to Figs. 5, 6 and 7.

Referring now to Fig. 5, the subassembly circuit X1 has a plurality of wire units WI and five connector housings 1 to 5 into which respective terminal fittings on the wire units W1 are inserted. The connector housings 1 to 5 are respectively for a hazard switch, for connection to another group of wiring harnesses, for a junction box, for a defogger switch, and for an overhead lamp lighting control unit. The subassembly circuit X1 includes no electric wires subjected to the splice process.

On the other hand, referring to Fig. 6, the subassembly circuit Y1 has a plurality of wire units W2 and five connector housings 6 to 10. The connector housings 6 to 10 are respectively for an air washer switch, for an overdrive selecting switch, for a shock absorber control switch, for an automatic transmission power selecting switch, and for an air washer body. The subassembly circuit Y1 includes electric wires subjected to the splice process. Junctions are respectively indicated by arrows at ends of the electric wires and J. Each of the junctions J is covered with an insulating tape, which is not illustrated in Fig. 6. In addition, the subassembly circuit Y1 includes so-called bulk terminals ST1 and ST2.The two bulk terminals ST1 illustrated on the left side are bulk terminals inserted into the connector housing 1 for a hazard switch at the time of assembling. On the other hand, the bulk terminals ST2 illustrated on the right side are bulk terminals inserted into the connector housing 4 for a defogger switch at the time of assembling.

Fig. 7 is a diagram showing a wiring harness obtained by collecting the subassembly circuits X1 and Y1 shown in Figs. 5 and 6. Each of junctions J is covered with an insulating tape as described above, which is not illustrated in Fig. 7. This insulating tape may adhere to an electric wire or the like at the time of assembling, which is one cause of degradation of workability of assembling. In addition, the bulk terminals ST1 and ST2 must be inserted into predetermined connector housings at the time of assembling, that is, there exist terminals which should be subjected to so-called "insertion in a post treatment". This is also one cause of degradation of workability.

Fig. 8 shows a subassembly circuit X2 manufactured by the manufacturing method according to one embodiment of the present invention. This subassembly circuit X2 comprises a plurality of wire units W3 and five connector housings 1 to 5, similarly to the subassembly circuit X1. The five connector housings 1 to 5 are the same as those in the subassembly circuit X1. The same connector housings are assigned the same reference numerals and hence, the overlapped description is omitted here.

The construction of the subassembly circuit X2 shown in Fig. 8 is characterized in that portions of electric wires to be connected by a press-connecting joint connector at the time of later assembling are U-turn portions U1 and U2 expanded in a loop shape. The U-turn portions U1 and U2 can easily be formed particularly if the electric wires are laid out using an automatic wire laying-out machine, as the electric wires may respectively be hung on wire laying-out pins which conform to the U-turn portions U1 and U2.

The automatic wire laying-out machine for automatically laying out the electric wires so as to manufacture the subassembly circuits may be an automatic wire laying-out machine as described in, for example, the prior applications of the applicant (Japanese Patent Application Serial No. 4155349, Japanese Utility Model Application Serial No. 4-43609, Japanese Patent Application Serial No. 4-163046, and Japanese Patent Application Serial No. 4-248300). The other automatic wire laying-out machines may be used.

Fig. 9 shows a subassembly circuit Y2 manufactured by the manufacturing method according to one embodiment of the present invention. This subassembly circuit Y2 comprises a plurality of wire units W4 and five connector housings 6 to 10 and corresponds to the subassembly circuit Y1 shown in Fig. 6.

The respective connector housings 6 to 10 are the same as the connector housings 6 to 10 shown in Fig. 6 and hence, the same connector housings are assigned the same reference numerals.

The construction of the subassembly circuit Y2 shown in Fig. 9 is characterized in that all the wire units W4 are respectively single-line electric wires and include no junction J. In addition, there is no so-called bulk terminals. Furthermore, portions of electric wires to be connected by a press-connecting joint connector at the time of later assembling are U-turn portions U3, U4 and U5 expanded in a loop shape.

The U-turn portions U3, U4 and U5 can simply be formed if the electric wires are laid out using an automatic wire laying-out machine, as in the subassembly circuit X2.

Fig. 10 is a circuit diagram showing a wiring harness manufactured according to one embodiment of the present invention which is assembled by collecting the subassembly circuits X2 and Y2, respectively shown in Figs. 8 and 9. In a manufacturing method according to this embodiment, the subassembly circuits X2 and Y2 are collected in the finished configuration, and the U-turn portions U1 and U3 in the subassembly circuits X2 and Y2 are connected to each other in a short-circuited manner by a press-connecting joint connector J/C1. Two electric wires included in the U-turn portion U4 formed in the subassembly circuit Y2 are connected to each other in a short-circuited manner by a press-connecting joint connector J/C2.In addition, the U-turn portions U2 and U5 in the subassembly circuits X2 and Y2 are combined with each other, and are connected to each other in a short-circuited manner by a press-connecting joint connector J/C3. It is not until the assembling process that the electric wires, which should be electrically connected to each other, are connected by the press-connected joint connector J/C in a shortcircuited manner. This is the great advantage of the manufacturing method in the embodiment. Such a pressconnecting joint connector J/C for short-circuited connection may be used for sometimes predetermined electric wires constituting a plural subassembly circuits: the U-turn portions U1 and U3; and sometimes of one subassembly circuit: the electric wires of the U-turn portion U4.

The foregoing connection of the electric wires in a short circuited manner at the assembling increases, as described above, the efficiency of the manufacture of the wiring harness as a whole.

Fig. 11 is a diagram for explaining an advantage in manufacturing the wiring harness by the foregoing manufacturing method according to the embodiment and particularly, the advantage of shortening a period required for the manufacture, which is shown in contrast to the conventional manufacturing method.

Fig. 11 shows on the upper side thereof one example of the number of days required to manufacture a wiring harness in the conventional manufacturing method. The measuring and cutting, stripping, and terminal crimping processes are carried out for each lot, and require, for example, two days.

The splice process is then carried out with respect to wire units which should be spliced to each other. The splice process is also carried out for each lot, and requires, for example, three days. During the days, the assembling process cannot be carried out with respect to wire units which need not be spliced to each other. Therefore, the wire units which need not be spliced to each other must wait for the assembling process until the splice process is terminated.

On the other hand, as shown on the lower side of Fig. 11, the manufacturing method according to this embodiment terminates the measuring and cutting, stripping, and terminal crimping processes of electric wires in two days. Immediately after this, the assembling process (the manufacturing process of subassembly circuits) can be carried out. Accordingly, the manufacturing term can, for example, be three days shorter than that of the conventional manufacturing method.

Fig. 11 shows a comparison between the methods each of which processes up to the assembling are carried out both by machinery and manually. Becuase the conventional method requires a manual splice process, the difference of manufacturing terms between the methods would be larger when the embodiment would be totally automated in order to process the every step up to the assembling.

Fig. 12 is a diagram for explaining another advantage in employing the manufacturing method according to one embodiment of the present invention, which is shown in contrast to the conventional manufacturing method.

Fig. 12A is an illustration showing a wiring harness manufactured by the present manufacturing method, for example, a wiring harness in which a head lamp circuit and a direction indicator circuit are connected to a windshield wiper circuit.

In the conventional manufacturing method, the splice process is carried out before the subassembly circuits are manufactured, it is therefore difficult to configurate the subassembly circuit which is designed divisionally by system.

On the other hand, in the manufacturing method according to one embodiment of the present invention shown in Fig. 12B, it is not until assembling that the connecting process is carried out by the press-connecting joint connector.

Consequently, it is possible to manufacture a windshield wiper circuit, a head lamp circuit, and a direction indicator circuit divisionally as subassembly circuits, and to collect the subassembly circuits, so that the connecting process can be carried out using the press-connecting joint connector.

Thus, the divisional design for the subassembly circuit by system becomes easy.

The advantage of the subassembly circuit being designed and manufactured divisionally by system is that the more complicated the circuits are, such as a wiring harness for an automobile, then the easier it would be to design the subassembly circuits for sharing. This is because the subassembly circuits can be connected at the assembling process and therefore easily be designed by system when the different systems or circuits should be connected, such as a wiring harness for an automobile which should provide:: (1) Circuits for a head lamp and a direction indicator connected to a circuit for connecting a windshield wiper switch and a windshield wiper motor to each other; (2) A circuit for operating four electromagnetic door locks when the automobile reaches at a predetermined speed connected to a circuit for connecting a speed meter with a speed sensor; (3) An interlocking circuit for spraying a washer liquid to the windshield wiper switch connected to a circuit obtained by (1); and (4) A circuit for connecting the circuit for the four electromagnetic door locks to a switch in a driver1 s seat connected to a circuit obtained by (2), to constitute a circuit for performing a centralized operation of the four electromagnetic door locks from the drivers seat.

Accordingly, it is easy to design the subassembly for sharing, as the subassembly circuits designed by system can simultaneously be shared easily.

Fig. 13 is a diagram showing an example of the construction of a drawing board for work required in assembling in the manufacturing method according to one embodiment of the present invention. In the manufacturing method according to this embodiment, manual operation will be carried out for collecting subassembly circuits in the finished configuration to form an assembly circuit. In order to collect a predetermined number of subassembly circuits for assembling, a drawing board 21 shown in Fig. 13 is used. On the drawing board 21, are circuit holding members 22 conforming to the finished configuration are arranged previously.

A worker puts a predetermined number of subassembly circuits on the holding members 22 to collect the predetermined number of subassembly circuits in the finished configuration.

Pressing spaces 23 for mounting a press-connecting joint connector are also secured to the drawing board 21. In addition, press-connecting joint connector stands 24 arranged adjacent to the pressing spaces 23 are provided on the drawing board 21. The pressing spaces 23 and the press-connecting joint connector stands 24 may be set in the longitudinal direction on the drawing board 21, as shown in Fig. 13A, or in the transverse direction on the drawing board 21, as shown in Fig. 13B.

Fig. 14 is a perspective view showing one example cf a press-connecting pressing machine 30 disposed in a pressing space 23 and one example of a press-connecting joint connector stand 24. The press-connecting pressing machine 30 for mounting a press-connecting joint connector is hung on a hook 32 mounted on an end of a wire 31 movable in the vertical direction. The press-connecting pressing machine 30 comprises a long supporting plate 33 and a hydraulic press cylinder 34 mounted on the supporting plate 33. Provided below the hydraulic press cylinder 34 is a pressing member 35 which is vertically operated by the cylinder 34. A recess 36 is formed in the lower surface of the pressing member 35 so that a cover portion 42b or a blade portion of the press-connecting joint connector 42 can be set in this recess 36.The pressconnecting pressing machine 30 further includes a positioning guide plate 37 extending in the horizontal direction from the supporting plate 33 and fastened to the lower portion of the supporting plate 33.

On the other hand, a plurality of supports 41, for example two, are studded on the surface of a drawing board 21 for assembling, and the press-connecting joint connector stand 24 is mounted on upper ends of the two supports 41. This connector stand 24 has an upper surface on which is formed a positioning projection 43 for setting a body housing 42b of the press-connecting joint connector. Connector stand 24 has a lower surface on which are projected positioning guides 44 adapted to engage with the positioning guide plate 37 of the press-connecting pressing machine 30. When the pressconnecting joint connector 42 is mounted, the positioning guide plate 37 is engaged with the positioning guide 44, and the hydraulic press cylinder 34 is operated in the state.

Consequently, the pressing plate 35 is lowered by the hydraulic press cylinder 34, so that the cover portion 42a or the blade portion set on the pressing plate 35 is fitted in the body housing 42b of the press-connecting joint connector 42.

At the time of assembling, the U-turn portions are formed by electric wires which should be electrically connected to each other among electric wires in a predetermined number of subassembly circuits, as described above. Such U-turn portions are projected from the subassembly circuits collected on the drawing board 21 to be set on the press-connecting joint connector body housing 42b set on the press-connecting joint connector stand 24.

U-turn portions are formed by the electric wires which should be connected to each other among the electric wires in the subassembly circuits, so that the connecting place can be displaced from the subassembly circuits. As a result, the Uturn portions can easily be set on the press-connecting joint connector, thereby simplifying the operation to mount the press-connecting joint connector on a necessary portion and therefore the press-connecting pressing machine to connect the electric wires to each other in a short-circuited manner.

The foregoing method of manufacturing a wiring harness is only one embodiment of the present invention. However, the present invention is not limited to the embodiment described.

Although in the embodiment, description was made of a case where the number of subassembly circuits used for assembling is only two for convenience of description and illustration, a lot of subassembly circuits may be collected to form an assembly circuit in manufacturing the actual wiring harness in many cases. Also in such cases, it goes without saying that the wiring harness can be manufactured using the manufacturing method according to the present invention.

Furthermore, the manufacture of a plurality of electric wires including the measuring and cutting process, the stripping process and the terminal crimping process and the manufacture of subassembly circuits using a plurality of wire units in the manufacturing method according to the present invention may be achieved by an automatic mechanized device or may be achieved manually by a worker. In addition thereto, various changes can be made within the range described in claims.

Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation.

Claims (11)

1. A method of manufacturing a wiring harness, comprising the steps of: manufacturing a plurality of wire units required to form a predetermined number of subassembly circuits by carrying out a measuring and cutting process for cutting an electric wire to a predetermined length, a stripping process for striping insulating sheaths at both ends of the electric wire measured and cut to expose conductors, and a terminal crimping process for crimping terminal fittings to the exposed conductors at both ends of the electric wire; manufacturing a predetermined number of subassembly circuits having no junction by respectively inserting the terminal fittings on the plurality of wire units into predetermined connector housings; and collecting the predetermined number of subassembly circuits thus manufactured in the finished configuration and connecting the electric wires which should be electrically connected to each other among the electric wires constituting each of the subassembly circuits in a short-circuited manner using a press-connecting joint connector at that point in time.

2. A method of manufacturing a wiring harness according to claim 1, wherein the press-connecting joint connector is mounted using a press-connecting pressing machine.

3. A method of manufacturing a wiring harness according to claim 1 or claim 2, wherein the subassembly circuits are manufactured in units of subassembly circuits which are easily shared among a plural types of wiring harnesses.

4. A method of manufacturing a wiring harness according to claim 3, wherein the unit of subassembly circuits are divided by system.

5. A method of manufacturing a wiring harness according to any of claims 1 to 4, wherein the subassembly circuits are manufactured in units of subassembly circuits which are easily mechanized.

6. A method of manufacturing a wiring harness according to claim 5, wherein the unit of subassembly circuits is constituted by the wire units respectively formed of single-line electric wires.

7. A method of manufacturing a wiring harness according to claim 5 or claim 6, wherein an automatic wire laying-out machine is used for automating the production of electric wires: the measuring and cutting process; the stripping process; and the terminal crimping process, and the production of the subassembly circuits, and the electric wires which should be electrically connected to each other after the subassembly circuits are collected in the finished configuration are laid out in such a manner that their portions to be connected are curved in a loop shape.

8. A method of manufacturing a wiring harness according to any of claims 5 to 8, wherein the portions to be connected of the electric wires respectively form loops in positions displaced from the subassembly circuits.

9. A method of manufacturing a wiring harness according to any of claims 5 to 8, wherein said press-connecting joint connector is fastened by a press-connecting pressing machine provided on a drawing board of an automatic wire laying-out machine.

10. A method of manufacturing a wiring harness substantially as herein described, with reference to, and as illustrated in, one or more of Figs. 4, 8, 9, 10, 11, 12B, 13 and 14 of the accompanying drawings.

11. A wiring harness produced by a method as claimed in any of the preceding claims.