Abstract:
A guide jig for an assembly plate for assembling a wire harness has a support sheath extending through the assembly plate, a guide lever axially movably inserted in the support sheath and a support plate secured to the support sheath. The guide lever can be held in its pulled-up position unrotatably relative to the support sheath. The support plate protrudes below the assembly plate by a smaller length than before.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a guide jig for use with an assembly plate for assembling a wire harness which is a bundle of wires arranged in a desired form into a unit. 
     2. Description of the Related Art 
     As shown in FIG. 9, an assembly plate comprising a plate member B and guide jigs A, arranged on the plate member B at predetermined positions, is used to assemble a wire harness. Wires a cut to a predetermined length are laid along the guide jigs A to form a bundle of wires having branches in a shape suitable for the desired purpose. Tapes t are wound around the bundle to prevent the wires from loosening. Finally, clamps and protectors (hereinafter referred to as accessory parts) are put on the bundle to form a wire harness. 
     Modern harnesses have a more complicated branch structure. Thus a greater number of guide jigs A have to be mounted in a smaller area. Such densely mounted guide jigs A will hamper taping and mounting of the clamps and protectors, thus remarkably lowering workability. 
     As a solution to this problem, the present applicant proposed a guide jig A for a wire harness assembly plate in Examined Japanese Utility Model Publication 62-20103. Namely, as shown in FIG. 10, this prior art jig is vertically movable with respect to the plate member to bring it to a lower position so as not to interfere the taping and clamping. 
     The prior art guide jig A includes a support sheath 2 extending through and secured to the plate B, a guide lever 5 vertically slidably inserted into the support sheath 2, a support plate 4 fixedly mounted on the support sheath 2 and provided with a lock mechanism 8 adapted to engage a pin 7 provided at bottom of the guide lever 5 to hold the guide lever in its pulled-up position. 
     In order to ensure that the pin 7 engages the lock mechanism 8 when the guide lever 5 is pulled up, a guide means is provided to guide the guide lever vertically and unrotatably with respect to the support sheath 2. The guide means comprises a slit 6 formed in the support plate 4 to extend vertically and adapted to receive the pin 7 on the guide lever 5. 
     This prior art guide jig A has to have a support plate 4 having a length equal to the length of movement of the pin 7. Thus the support plate 4 protrudes considerably downwards form the plate member 1. This increases the possibility of the frame 4 being deformed or broken during transportation. Thus, it was necessary to transport the assembly plate with the guide jigs removed and assemble the plate with the guide jigs when forming a wire harness. 
     An object of this invention is to provide a guide jig which obviates the shortcomings of the prior art guide jig by reducing the amount of protrusion from the bottom surface of the plate member. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, there is provided a guide jig for an assembly plate for assembling a wire harness, having a support sheath extending through the assembly plate and fixed thereto, a guide lever axially movably inserted in the support sheath, and a guide member fixed to the top of the guide lever for guiding the wire harness. The guide lever is provided, at the bottom end thereof, with an engaging portion and a support plate is fixedly mounted on the support sheath at a portion below the assembly plate and is provided with locking means for engaging with the engaging portion to hold the guide lever in its pulled-up position. The guide means is provided for guiding the guide lever so as to be movable vertically along the support sheath and unrotatable relative to the support sheath. The guide means has a guide portion provided on the guide lever so as to extend vertically and means is provided on one of the support sheath and the support plate for engaging with the guide portion to prevent the guide lever from turning relative to the support sheath. 
     The turn preventive means provided on the support sheath or support plate is adapted to engage the engaging portion on the guide lever to extend along its length, thereby preventing the guide lever from turning relative to the guide sheath. This makes it possible to reduce the length of the support plate and thus the length of the guide jig below the assembly plate. 
    
    
     Other features and objects of the present invention will become apparent from the following description taken with reference to the accompanying drawings, in which: 
     FIG. 1 is a partially exploded perspective view of the guide jig for an assembly plate for assembling a wire harness; 
     FIG. 2a is a sectional front view of the guide jig showing its assembled state, and FIG. 2b is a sectional side view of the same; 
     FIGS. 3a-3e are views of the guide jig showing its different operational positions; 
     FIG. 4 is a perspective view of the wire harness assembly plate showing how it is packaged; 
     FIG. 5a is an exploded perspective view of the second embodiment, and FIGS. 5b and 5c are sectional views of the same; 
     FIG. 6a is an exploded perspective view of the third embodiment, and FIGS. 6b and 6c are sectional views of the third embodiment; 
     FIG. 7a is an exploded perspective view of the fourth embodiment, and FIG. 7b is a sectional view of the same; 
     FIGS. 8a-8f are views of the fourth embodiment, showing different operational positions; 
     FIG. 9 is a perspective view of a wire harness showing how it is laid; and 
     FIG. 10a is a front view of the prior art, and FIG. 10b is a right-side view of the same. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     As shown in FIG. 1, a guide portion 20 for supporting wires a (bundle of wires) is screwed into a guide lever 21 and fixed thereto (FIG. 2). The guide lever 21 extends through a support sheath 22. 
     The guide lever 21 has both sides thereof cut to form flat surfaces 21a. The support sheath 22 is formed with a through hole 22a having the same cross-section as the guide lever 21 so that the guide lever is supported so as to be unrotatable but movable in the axial direction. The guide lever 21 may also be held unrotatable by a key and groove structure. The guide lever 21 a longitudinally elongated groove 23 formed in a lower part thereof. 
     A support plate 26 is fixed to a lower surface of an assembly plate 1 and is provided with a lock mechanism which engages in a groove 23 and holds the guide lever in its upper position. The lock mechanism includes a cam plate 29, an L-shaped piece 24 and a coil spring 25 mounted on the guide lever 21 between the L-shaped piece 24 and the coil spring 25. 
     The cam plate 29 is H-shaped having two pairs of projections opposed in a symmetric relation with respect to the axis of rotation of the cam plate 29 (see FIG. 2). The cam plate 29 is loosely mounted on a shaft 31 which extends through the support plate and is positioned by virtue of an E ring 32 and a spacer 30. 
     The groove 23 has such a depth and length that the cam plate 29 can freely rotate when it is centered with respect to the length of the groove 23 when lever 21 is in the position illustrated in FIGS. 3a and 3c. In particular, the distance between the axis of rotation of the cam plate 29 and the surface of the guide lever 21 is set to be larger than the distance from the axis of rotation to the each side edge of the cam plate 29 which extend between projections 29d and 29a and projections 29c and 29b, respectively. 
     The coil spring 25 is adapted to be pressed against the support plate 26 when a lower one of the pair of projections abuts against the top shoulder portion of the groove 23 and the upper one of the pair of projections abuts against the periphery of the guide lever 21 above the groove 23, as illustrated in FIG. 2(a). 
     The L-shaped piece 24 has a first portion extending parallel to a bottom edge of the assembly plate 1 for a predetermined length L and a second portion extending vertically from the free end of the first portion toward the assembly plate. The length L is so set that as shown in FIG. 2a, the tip 24a of the L-shaped piece will move in a plane opposite the axis of rotation of the cam plate 29 with respect to lever 21, and also moves within the radial range of rotation of the cam plate. 
     The L-shaped piece 24 has a vertical length such that when the spring 25 is compressed, from the state shown in FIG. 3(e), between support plate 26 and L-shaped piece 24, to the limit thereof, tip 24a will pass into an area between lower projections 29a and 29b of the cam plate 29, abut against the cam plate 29 and thus rotate cam plate 29 so that projection 29c will engage in the groove 23. 
     Now the operation of this embodiment is described with reference to FIGS. 3a-3e. 
     FIG. 3b shows the state or level of guide portion 20 for laying wires therein. One 29a of the bifurcated projections 29a and 29b of the cam plate 29 is in engagement with the top end of the groove 23 in the guide lever 21 and the other projection 29b with the side of the guide lever 21. Also, the guide lever 21 is biased downwards by the spring 25. Thus, the cam plate 29 is prevented from turning counterclockwise further and the guide lever 21 is held at ths level. Namely, while laying wires, any undue lowering of the guide lever 21 by the biasing force of the spring 25 is prevented. 
     As shown in FIG. 3c, when the guide lever 21 is pulled up, by the operator, in this state, as the cam plate 29 pivots while being pushed by the tip 24a of the L-shaped piece 24 such that projections 29a and 29b are received in the groove 23. Thus, as shown in FIG. 3d, when the guide lever 21 is released, it will descend biased by the spring 25, thus pivoting the cam plate 29 with the shoulder of the grooves 23 so that it will take a vertical H position. This allows the guide lever 21 to move further down. As shown in FIG. 3e, the guide lever 21 descends further by gravity and stops when the guide portion 20 abuts the plate member 1. In this state in which the bundle of wires are kept afloat by either portions of the wire harness which are supported in other guide portions 20, accessory parts are mounted. 
     Then when the operator raises the guide lever 21 until the coil spring 25 is compressed to the limit as shown in FIG. 3a, the tip 24a of the L-shaped piece 24 will come into abutment with the outer one 29a of the lower bifurcated projections 29a and 29b, thus pivoting the cam plate 29. Thus, the inner one 29c of the upper bifurcated projections 29c and 29d enters into the groove 23. When the guide lever 21 is released in this state, it will descend biased by the coil spring 25, so that the bifurcated projection 29c engages the top end of the groove 23 while the other one 29d abuts the side of the guide lever 21. Namely, the entire device returns to the level for laying wires shown in FIG. 3b and are kept in this state. 
     The level for laying wires can be changed by removing the guide portion 20, pulling out the guide lever 21 downwards and inserting a guide lever of a desired length into the support sheath 22. This allows the manufacturer and user to control the guide levers 21 and the support plates 26 separately. They can manufacture or order guide levers of different heights according to the desired levels for laying wires. This permits a substantial reduction in cost. 
     In the abovementioned embodiment, by providing the flat surfaces 21a on the guide lever 21 and the complementary flat surfaces 22a on the support sheath 22, both members 21 and 22 are prevented from turning with respect to each other. Further by securing the support plate 26 to the support sheath 22, the support sheath 22 can be stably supported by the plate 1. 
     Further, since the cam plate 29 is covered by the support plate 26, the elevating mechanism including the cam plate 29 is protected against damage even if they are interfered with by the assembly plate during assembly. Also, they are protected against damage by hand. The assembly plates thus assembled may be packed, e.g. with paper pipes 40 and tapes 41 with two assembly plates brought together face to face as shown in FIG. 4. 
     FIGS. 5 and 6 show a guide jig according to a second embodiment provided with a locking mechanism similar to that of the above-mentioned embodiment. Means for preventing the guide lever 21 from turning are different from those of the first embodiment, however. 
     The guide jig shown in FIGS. 5a to 5c has a guide lever 21 in the shape of a polygonal shaft. Its opposed flat surfaces 21a are in contact with the inner sides of the support plate 26 to prevent the lever 21 from turning. The guide jig is also provided with a ring-shaped seating plate 32 secured to the top end of the support plate 26 by welding. The seating plate 32 has its edge partially cut and raised to form claws 33. This arrangement serves to reinforce connection between the support plate 26 and the assembly plate 1. Also, when mounting the guide jig on the plate member 1, the claws 33 will bite into the bottom surface of the plate member 1, thus preventing the guide jig from turning. The guide jig is coated with fluororesin for smooth operation of the guide lever 21. 
     The guide jig shown in FIGS. 6a to 6c has a guide lever 21 in the shape of a round shaft formed with a longitudinally extending groove 34. Rollers 35 secured to the support plate 26 are inserted in the groove 34 to prevent the guide lever 21 from turning. At the same time, the guide lever 21 is prevented from coming off the assembly comprising members 22, 32, 33, 35 (FIG. 6a) by limiting the lengthwise dimension of the groove 34. This guide jig, too, is provided with a seating plate 32 having claws 33. 
     FIGS. 7a and 7b show a guide jig provided with a conventional locking mechanism. It has a guide lever 51 in the shape of a polygonal shaft and a support sheath 52 formed with a through hole 52a having the same cross-section as the guide lever 51 to prevent the guide lever 51 from turning. 
     As shown in these figures, the guide lever 51 is provided at its bottom end with a projection 51a extending therethrough perpendicular to the lever 51, while the support plate 53 is provided with an engaging plate 54 adapted to engage the projection 51a. Also, a coil spring 57 is mounted on the guide lever 51 between the bottom end of the support sheath 52 and the projection 51a. 
     The support plate 53 comprises a plate member 53a having an L-shaped cross-section and a plate 53b provided inside the plate member 53a to extend parallel to its vertical wall. A predetermined space is defined therebetween. The plate 53b is formed with a groove 53c through which the projection 51a is adapted to move. 
     The engaging plate 54 is mounted in the above-mentioned space, between plate 53b and plate member 53a, at one side of the groove 53c in the plate 53b so as to be pivotable and inclinable toward the plate member 53a. It is biased by a spring 55 toward the other side of the groove 53c and the plate 53a. Its rotation is restricted by a stopper 56. 
     The engaging plate 54 has a cam surface 54a extending obliquely upward across the groove 53c from the pivoting point and is formed with a cutout 54b extending from the top end of the cam surface 54a toward the pivoting point. Further, the engaging plate 54 is provided with a projection 54c extending upwardly from the central part of the bottom of the cutout 54b and adapted to engage the projection 51a. Further, at one side of the projection 54c near the pivoting point, there is provided an oblique projection 54d as shown in FIG. 8e. Since the projections 54c and 54d are bent toward the plate 53a as shown in FIG. 8(e), the projection 51a will not catch on the tips of projections 54c and 54d. 
     This locking mechanism operates in the following way. By pulling up the guide lever 51 inserted in the support sheath 52 with its projection 51a inside the groove 53c, as shown in FIG. 8a, the projection 51a is adapted to abut the cam surface 54a, thus turning the engaging plate 54 toward the pivoting point. 
     A shown in FIGS. 8b and 8c, when the projection 51a overpasses the top end of the cam surface 54a, the engaging plate 54 will pivot in a reverse direction, biased by the spring 55. Thus, the projection 51a gets into the cutout 54b and is engaged by the projection 54c, so that the guide lever 51 is fixed in this position. This state is the level for laying wires. 
     As shown in FIG. 8d, when the guide lever 51 is pulled up further, the projection 51a is released from the projection 54c, allowing the engaging plate 54 to pivot under the biasing force of the spring 55 until its projection 54d is located under the projection 51a. When the guide lever 51 is released in this state, as shown in FIGS. 8e and 8f, it is pushed down biased by the coil spring 57, so that the projection 51a descends while pushing the engaging plate 54 toward the plate member 53a by abutting the inclined surface of the projection 54d. Thus, the engaging plate 54 pivots further to its initial position, i.e. until it abuts the stopper 56. This state is the level for mounting the accessory parts.