Patent Publication Number: US-6710262-B2

Title: Flat harness assembling apparatus and method

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an apparatus and method for assembling a flat harness in which juxtaposed electric wires are covered with a sheet. 
     2. Description of the Related Art 
     A method for producing a flat harness in which a plurality of electric wires are laterally arranged in a flat form and integrated with one another is disclosed in Japanese Patent Public Disclosure No. HEI 9-29015. In this method, a plurality of electric wires are arranged in a flat plane to form a harness, and are disposed on a central portion of a flexible sheet having a hot melt adhesive on a surface thereof. Opposite side ends of the sheet, which extend beyond opposite side ends of the flat harness, are folded over onto the harness. Distal parts of the opposite side ends of the sheet are overlapped on the harness. In this condition, the harness and sheet are clamped between upper and lower dies of a heating press machine, and are heated and pressed to be joined together. 
     In this manner, a plurality of electric wires are arranged in a flat form and covered with a sheet, on which a hot melt adhesive is applied, to produce a flat harness. Such a flat harness is suitable for containment in a narrow space, such as the space between a roof panel and a molded ceiling in a vehicle, such as an automobile. However, an apparatus for producing such a flat harness can be large and involve complex processes. 
     For example, in order to envelope the harness having a plurality of electric wires together with a sheet provided with hot melt adhesive on a surface, it is necessary to incorporate a heating device in a molding press in order to soften the hot melt adhesive. This necessarily involves the provision of a large scale production apparatus. In order to carry out a suitable heat pressing process in a molding press, the following steps are required. The opposite side ends of the sheet must be folded to make creases on the sheet, and then unfolded or returned to their original position. Next, the sheet must be enveloped around the harnss wires to temporarily hold them, prior to heating and pressing. 
     A sheet provided with a pressure sensitive adhesive on a surface of the sheet may be used instead of a sheet on which hot melt adhesive is applied. However, a worker will often touch the pressure sensitive adhesive inadvertently, which will interfere with the assembly and covering process. Furthermore, it is difficult to properly cover the harness wires with the she(t in a compact manner while tightly attaching the sheet to the opposite side ends of the juxtaposed harness wires. 
     SUMMARY OF THE INVENTION 
     The present invention has been made in view of the above described situation. Accordingly, an object of the present invention is to provide apparatus and method for easily and properly producing a flat harness by covering juxtaposed electric wires with a sheet having a pressure sensitive adhesive on a surface thereof. 
     According to one aspect of the present invention, there is provided an apparatus for assembling a flat harness in which a plurality of juxtaposed electric wires are covered by a sheet having a pressure sensitive adhesive layer on a first surface thereof. The apparatus includes a covering device for assembling the sheet around the plurality of juxtaposed wires. The covering device includes a central plate on which a central portion of the sheet is supported, a first side plate connected through a first hinge portion to a first side edge of the central plate in a foldable manner for supporting a first lateral portion of the sheet, and a second side plate connected through a second hinge portion to a second side edge of the central plate in a foldable manner for supporting a second lateral portion of the sheet. The covering device also includes an engagement device for holding the sheet supported on the ceniral plate the first side plate, and the second side plate. 
     According to a further aspect of the present invention, the engagement device includes an engagement plate having a surface which is configured to contact the first surface of the sheet. The engagement plate may be connected through a third hinge portion to a side edge of the second side plate in a foldable manner. The surface of the engagement plate may include a release agent layer provided thereon. 
     According to a further aspect of the present invention, the engagement device includes a suction source for applying a negative pressure to a second surface of the sheet. Further, the central plate may include a porous plate provided on an upper surface thereof, and the suction source may apply the negative pressure to the second surface of the sheet through the porous plate. 
     According to a further aspect of the present invention, the covering device may further include a sheet positioner for aligning the sheet in a predetermined position on the central plate, the first side plate and the second side plate. The sheet positioner may include a sheet end positioning portion for aligning an end of the sheet. The sheet end positioning portion may be provided on the second side plate. The sheet positioner may include sheet lateral edge positioning portions for aligning lateral edges of the sheet. The sheet lateral edge positioning portions may be provided on the central plate, the first side plate and the second side plate. 
     According to a further aspect of the present invention, at least one clamp member for holding a portion of the plurality of juxtaposed electric wires may be provided. Further, two clamp members may be provided for holding opposite end portions of the plurality of juxtaposed electric wires. 
     According to a further aspect of the present invention, a support member for supporting the covering device in a position between the two clamp members may be provided. The support member may be movable between a first position in which the covering device is spaced away from the plurality of juxtaposed electric wires and a second position in which the covering device is adjacent to the plurality of juxtaposed electric wires. 
     According to another aspect of the present invention, a method for assembling a flat harness is provided which includes holding a plurality of juxtaposed electric wires with at least one clamping member, providing a central plate and first and second side plates which are connected in a foldable manner to first and second side edges of the central plate through first and second hinge portions, and providing a sheet having a pressure sensitive adhesive layer on a first surface thereof, wherein the sheet has a central portion, a first lateral portion and a second lateral portion. The method includes mounting the sheet on the central plate, the first side plate and the second side plate, and pressing an engagement plate having a release agent layer onto the second lateral portion of the sheet to hold the second lateral portion of the sheet against the second side plate. 
     The method further includes disposing the plurality of juxtaposed electric wires on the central portion of the sheet, folding the first side plate onto the central plate such that the first lateral portion of the sheet is folded over and fixed on the plurality of juxtaposed electric wires, releasing the engagement plate from the second lateral portion of the sheet, and folding the second side plate onto the central mounting plate such that the second lateral portion of the sheet is folded over and fixed on the plurality of juxtaposed electric wires. 
     The method may further include aligning the sheet on the central plate, the first side plate and the second side plate with a sheet positioner. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above, and other objects, features and advantages of the present invention will be made apparent from the following description of the preferred embodiments, given as nonlimiting examples, with reference to the accompanying drawings in which: 
     FIG. 1 is a perspective view of an embodiment of a flat harness assembling apparatus in accordance with the present invention; 
     FIG. 2 is a perspective view of an embodiment of a covering device for assembling a sheet around a plurality of juxtaposed wires in accordance with the present invention; 
     FIG. 3 is a cross sectional view of the covering device of FIG. 2; 
     FIG. 4 is a side view of a clamp member shown in FIG. 1, illustrating an open condition; 
     FIG. 5 is a side view of a clamp member shown in FIG. 1, illustrating a closed or clamping condition; 
     FIGS. 6A to  6 C are views showing initial steps of a flat harness assembling method in accordance with the present invention, using the covering device shown in FIG. 2; 
     FIGS. 7A and 7B are views showing additional steps of a flat harness assembling method in accordance with the present invention, using the covering device shown in FIG. 2; 
     FIG. 8 is a view of a flat harness including electric wires covered with a sheet; 
     FIG. 9 is a cross sectional view of the flat harness of FIG. 8; 
     FIG. 10 is a cross sectional view of another embodiment of a covering device for assembling a sheet around a plurality of juxtaposed wires in accordance with the present invention; 
     FIG. 11 is a side view of another embodiment of a flat harness assembling apparatus in accordance with the present invention; and 
     FIG. 12 is a cross sectional view of another embodiment of an engagement device in accordance with the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than is necessary for the fundamental understanding of the present invention, the description is taken with the drawings making apparent to those skilled in the art how the forms of the present invention may be embodied in practice. 
     Embodiments of the present invention will be described below with reference to the drawings. 
     FIGS. 1 to  3  show an embodiment of a flat harness assembling apparatus in accordance with the present invention. The flat harness assembling apparatus includes a pair of clamping members  2  that position and hold juxtaposed electric wires  1 , and a covering device  4  to be used for covering the electric wires  1  with a sheet  3 . 
     The sheet  3  may be made of any material having suitable elasticity and shape-retention characteristics, such as urethane foam. The sheet  3  may be any suitable thickness, such as 1 mm, and a width sufficient to cover the rear and front surfaces of the electric wires  1 . A suitable pressure sensitive adhesive is applied to a surface of the sheet to form a pressure sensitive adhesive layer. A separate removable sheet, such as paper, may be attached to the pressure sensitive adhesive layer in order to protect it prior to use. 
     Each clamping member  2  includes a support block  6  standing on a support board  5 , a clamping mechanism  7  provided on a rear portion of the support block  6 , and an electric wire support portion  8  provided on an upper surface of the support block  6 . A plurality of support grooves  9  are provided in the electric wire support portion  8 , and are configured for supporting various types of electric wires  1 . The respective electric wires  1  are supported in the respective support grooves  9  to laterally position the electric wires  1 . 
     As shown in FIGS. 4 and 5, each clamping mechanism  7  includes a support plate  11  having a lower end supported through a support axle  10  on the support block  6 , a rocking arm  13  having a proximal end supported through a support axle  12  on the support plate  11 , a pressing member  14  made of any suitable material, such as a synthetic rubber, and secured to a distal end of the rocking arm  13 , and an operating lever  16  coupled through a link member  15  to an upper rear end of the support plate  11 . A distal end of the operating lever  16  is coupled through a coupling axle  17  to a proximal end of the rocking arm  13 . 
     The operating lever  16  can rotate the rocking arm  13  between a retracted position shown in FIG. 4 and a clamping position shown in FIG.  5 . The pressing member  14  presses upper surfaces of the electric wires  1  to clamp the electric wires  1  between the pressing member  14  and the electric wire support portion  8 . The clamping mechanism  7  may be provided with a locking portion (not shown) for detachably holding the rocking arm  13  in the clamping position. 
     FIGS. 2 and 3 show an embodiment of a covering device  4  for assembling a sheet around a plurality of juxtaposed wires of a flat harness. The covering device  4  includes a central plate  18  on which a central portion of the sheet  3  is mounted, a first side plate  19  coupled to a side edge of the central plate  18  in a foldable manner, a second side plate  20  coupled to the other side edge of the central plate  18  in a foldable manner, and an engagement plate  21  coupled to the second side plate  20  in a foldable manner. 
     The central plate  18 , first side plate  19 , second side plate  20  and engagement plate  21  are made of any suitable material, such as synthetic resin or metal. They are coupled to one another in a foldable manner by any suitable structure, such as by hinge portions  22 . A longitudinal dimension of the central plate  18  may be slightly greater than a length of the sheet  3  while a lateral dimension of the central plate  18  is about one third of a width of the sheet  3 . Thus, the central portion of the sheet  3  may be disposed on the central plate  18 . 
     Longitudinal and lateral dimensions of the first side plate  19  may be substantially the same as those of the central plate  18 . A longitudinal dimension of the second side plate  20  may also be substantially the same as that of the central plate  18 . The first and second side plates  19  and  20  and central plate  18  are juxtaposed and spaced a predetermined distance away from one another. A transparent thin flexible tape  29  is adhered to upper surfaces of the plates  18 ,  19  and  20 . The first and second side plates  19  and  20  are coupled to the opposite side edges of the central plate  18  through hinge sections  22 , which may be formed by the transparent thin tape  29  extending between the spaced plates. 
     A bar member  23  having a predetermined width is secured on an upper surface of a distal side end (free end) of the second side plate  20 . An engagement plate  21  is provided along a side surface of the bar member  23 . A transparent thin flexible tape  29  is adhered to upper surfaces of the bar member  23  and the engagement plate  21 . The second side plate  20  and engagement plate  21  are interconnected in a foldable manner through a hinge section  22 , which may be may be formed by the transparent thin flexible tape  29  extending therebetween. 
     A sheet positioner having substantially the same thickness as the sheet  3  is secured to upper surfaces of the central plate  18 , the first side plate  19  and the second side plate  20 . A sheet end positioning portion  24  of the sheet positioner is provided on the second side plate  20  along the bar member  23 , in order to align an end of the sheet  3 . Lateral edge positioning portions  25  of the sheet positioner are provided on the plates  18 ,  19  and  20 , in order to align opposite lateral edges of the sheet  3 . 
     The engagement plate  21  includes a third side plate  26  having substantially the same longitudinal and lateral dimensions as the second side plate  20 , and a bar member  27  secured to an upper surface of a distal side end of the third side plate  26 . A release agent of any suitable material, such as a silicone base material or a fluorine base material, is adhered to an upper surface of the bar member  27  to form a release agent layer  28 . The release agent may be applied to an adherent tape for application to the bar member  27 . 
     A method for assembling a flat harness using the flat harness assembling apparatus including a covering device  4  as described above will be explained below. Firstly, after the clamping members  2  hold a plurality of electric wires  1 , the sheet  3  is disposed on the covering device  4 . That is, as shown in FIGS. 2 and 3, the central plate  18 , first and second side plates  19  and  20 , and engagement plate  21  of the covering device  4  are unfolded. The sheet  3 , from which the release paper is removed, is mounted on the central plate  18  and first and second side plates  19  and  20 . A side end and opposite right and left lateral edges of the sheet  3  are brought into contact with the positioning portions  24  and  25  to align the sheet  3 . 
     Secondly, as shown in FIG. 6A, the engagement plate  21  of the covering device  4  is folded onto the second side plate  20 . The bar member  27  provided with the release agent layer  28  presses the surface of a lateral portion of the sheet  3 . The covering device  4  is moved below the electric wires  1  held by the clamping members  2 . When the covering device  4  is raised, as shown in FIG. 6B, the front surface of the sheet  3  is pressed onto the bottom surfaces of the electric wires  1  to adhere the electric wires  1  to the pressure sensitive adhesive layer on the sheet  3 . In this manner, it is possible to dispose the electric wires  1  on a given position on the central portion of the sheet  3  by positioning the electric wires  1  with respect to the bar member  27  of the covering device  4 . 
     Thereafter, as shown in FIG. 6C, the first side plate  19  is folded onto the central plate  18  to overlap and adhere the lateral end of the sheet  3  onto the top surfaces of the electric wires  1 . Then, as shown in FIG. 7A, the first side plate  19  and engagement plate  21  are unfolded. After the sheet  3  is released, as shown in FIG. 7B, the second side plate  20  is folded onto the central plate  18  to overlap and adhere the other lateral end of the sheet  3  onto the electric wires  1 . 
     As described above, the electric wires  1  are covered with the sheet  3  by using the covering device  4 , as shown in FIGS. 8 and 9. Accordingly, it is possible to easily and properly assemble a flat harness  31  suitable for being arranged in a narrow space defined between a roof panel and a molded ceiling in a vehicle such as an automobile. That is, the engagement plate  21  holds a lateral end of the sheet  3  mounted on the central plate  18  and first and second side plates  19  and  20  of the covering device  4 . The first side plate  19  is folded onto the central plate  18 . After releasing the engagement plate  21  from the sheet  3 , the second side plate  20  is folded onto the central plate  20 . The sheet  3  provided with the pressure sensitive adhesive layer on the surface thereof covers the top and bottom surfaces of the electric wires  1 . Accordingly, it is possible to cover the electric wires  1  together with the sheet by using the covering device  4  without any problems caused by a worker inadvertently touching the pressure sensitive adhesive layer on the sheet  3 . 
     It is possible to c over the electric wires  1  with the sheet  3  so that the sheet  3  closely aligns with the right and left side ends of the electric wires without causing any clearances between the electric wires  1  and the folded portions of the sheet  3 , if a width of the central plate  18  is the same as a width of the electric wires  1 . Furthermore, it is possible to precisely align a covering position of the sheet  3  with respect to the electric wires  1  by using the positioning portions  24  and  25  to precisely set the sheet mounting position. Accordingly, as shown in FIG. 9, it is possible to precisely set a distance L from a side end of the flat harness  31  to a folded position of the sheet  3 . It is also possible to properly arrange other electric wires  32  on the flat harness  31  with respect to the folded position of the sheet  3 . 
     As described above, a sheet positioner portion having substantially the same thickness as that of the sheet  3  is adhered to the upper surface of the second side plate  20 . Further, a sheet positioner portion having substantially the same thickness as that of the sheet  3  is adhered to left and right portions of the upper surfaces of the central plate  18  and the first and second side plates  19  and  20 . It is also possible to position the sheet  3  on the central plate  18  and first and second side plates  19  and  20  by applying color-code indicators on an mounting area of the sheet  3  instead of providing the positioning portions  24  and  25 . 
     As shown in the above embodiment, the engagement device including the engagement plate  21  connected through the hinge portion  22  to the side edge of the second side plate  20  is provided on the covering device  4 . It is possible to clamp and hold the sheet  3  between the engagement plate  21  and the second side plate  20  by mounting the sheet  3 , which is provided with the pressure sensitive adhesive layer on a surface thereof, on the central plate  18  and first and second side plates  19  and  20 , and by folding the engagement plate  21  onto the second side plate  20 . It is also possible to prevent the sheet  3  from being damaged while releasing the sheet  3  from the engagement plate  21 , since the separate agent layer  28  on the engagement plate  21  permits easy separation of the engagement plate  21  from the sheet  3 . 
     As shown in FIG. 10, another embodiment of an engagement device may include a separate engagement plate  34  provided with a release agent layer  33  on a bottom surface thereof, and a grip  35  secured to an upper surface of the engagement plate  34 . The separate engagement plate  34  is not connected to the central plate  18  and first and second side plates  19  and  20 . The sheet  3  provided with the pressure sensitive adhesive on a surface thereof is mounted on the central plate  18  and first and second side plates  19  and  20 . The engagement plate  34  holds the sheet  3  by pressing the release agent layer  33  onto the lateral end of the sheet  3 . 
     The hinge portions  22  are made of the transparent thin tape connecting the first and second side plates  19  and  20  to the opposite side edges of the central plate  18  in the above embodiment. As shown in the embodiment of FIG. 11, hinges  43  may instead be provided for connecting the first and second side plates  19  and  20  to the opposite side edges of the central plate  18 . 
     As shown in FIG. 12, a porous plate  36  formed of any suitable material, such as a sintered metal or a perforated metal plate, may be provided on an upper surface of the central plate  18 . In this embodiment, the engagement device includes a suction source  38 , such as a vacuum pump, to apply a negative pressure to a sealed interior  37  in the central plate  18  to suck the bottom surface of the sheet  3  onto the porous plate  36 . 
     According to the above construction, the sheet  3  provided with the pressure sensitive adhesive layer on the surface of the sheet  3  is mounted on the central plate  18  and first and second side plates  19  and  20 . The suction source  38  is actuated to suck the central portion of the sheet  3  onto the central plate  18 . The first side plate  19  is folded onto the central plate  18  to overlap and fix the lateral end of the sheet  3  onto the electric wires  1 . Then, the second side plate  20  is folded onto the central plate  18  to overlap and fix the other lateral end of the sheet  3  onto the electric wires  1 . 
     As shown in the above embodiment, the clamping members  2  clamp the juxtaposed electric wires  1  to position them. The sheet  3  provided with the pressure sensitive adhesive layer on the surface thereof is mounted on the covering device  4 . Covering of the electric wires  1  with the sheet  3  can be easily carried out by using the covering device  4 . 
     Furthermore, as shown in FIG. 11, a support unit  42  may be provided which includes a support pole  39  standing on the support board  5  and a rocking bracket  40  supported rotatably on a support axle  41  provided on a top of the support pole  39 . The covering device  4 , which includes the central plate  18  and first and second side plates  19  and  20 , may be supported rotatably between a lower standby position spaced away from the holding position of the electric wires  1  and an upper covering position adjacent to the holding position of the electric wires  1 . In this manner, after the sheet  3  is set on the covering device  4  at the lower standby position, the device  4  is moved to the upper covering position. While the engagement device holds the sheet against the covering device  4  at the upper covering position, it is possible to carry out covering of the electric wires  1  with the sheet  3  by using the covering device  4 . Further, the support unit  42  can be provided for the covering devices of any of the disclosed embodiments, which include the various engagement devices. 
     Although the invention has been described with reference to exemplary embodiments, it is understood that the words that have been used are words of description and illustration, rather than words of limitation. Changes may be made within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the invention in its aspects. Although the invention has been described with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed. Rather, the invention extends to all functionally equivalent strictures, methods, and uses such as are within the scope of the appended claims. 
     The present disclosure relates to subject matter contained in priority Japanese Application No. 2002-138998, filed on May 14, 2002, which is herein expressly incorporated by reference in its entirety.