JP2008171597A - Flexible flat harness and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flexible flat harness in which flexibility is maintained, which is high in waterproof characteristics, which has superior durability even in a water wetted environment, which is easy to manufacture, and in which productivity can be improved. <P>SOLUTION: The flexible flat harness 10 is equipped with a flexible printed board 20, and an elastic protective member 30 which covers the outer peripheral surface of this flexible printed board 20 and which has waterproof characteristics. The elastic protective member 30 has waterproof plugs 31 to 33 of a shape of blocking insertion holes 91a to 93a of waterproof connectors 91 to 93 in the vicinity of the end part of the flexible printed board 20. In the flexible printed board 20, since the terminal part is water stopped in the insertion holes 91a to 93a of the respective waterproof connectors 91 to 93 by the waterproof plugs 31 to 33 and covered with the elastic protective member 30, high durability is realized while flexibility is maintained without water absorption or corrosion. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a flexible flat harness composed of a flexible printed circuit (FPC) and the like, and a manufacturing method thereof, and more particularly to a flexible flat harness having a structure excellent in waterproofness and a manufacturing method thereof.

  For wiring of automobiles and office automation equipment, wire harnesses with a structure in which a plurality of electric wires are bundled are generally used. However, in recent years, due to demands for higher wiring density, it is lighter, thinner and higher density. Flexible flat harnesses using flexible printed circuit boards that can be made as wiring members have been widely used.

  In such a flexible flat harness, for example, a wiring made of a conductor pattern is formed by etching or the like on a copper-clad laminate in which a rolled copper foil is laminated on one side of a base film made of an insulating resin, and covered with a protective film such as a coverlay. It consists of a structure using a flexible printed circuit board instead of a plurality of electric wires.

  And in the connector using this flexible printed circuit board as a harness, for example, the child housing has a terminal support portion, and the terminal support portion supports the connection terminal in a state in which the distal end portion and the base end portion protrude outward. Some terminal support portions are provided with a lid that can be freely opened and closed via a hinge. The cover of this connector covers and clamps the connection part between the terminal part of the flexible flat harness and the base end part of the connection terminal from both sides in the connection direction, and water absorption tape is attached to the outer edge part of the opposing surface of the cover body. Each is provided, and the water absorbing tape is configured to seal the inside of the lid body by absorbing and expanding water (see, for example, Patent Document 1).

In addition, when the flexible printed circuit board seal body is fitted to the connector's fitting part, and the contact part of this flexible printed circuit board is connected to the press contact terminal, the locking protrusion can be engaged with and disengaged from the locking hole. A device that is configured to be locked to prevent moisture from entering the connector is also known (for example, see Patent Document 2).
JP 2005-347143 A JP 2001-155815 A

  However, in the conventional connectors disclosed in Patent Document 1 and Patent Document 2 described above, the flexible printed circuit board formed of an insulating film made of a water-absorbing material is used as a harness in a bare state. For this reason, when used in a wet environment, there is a problem that each characteristic such as mechanical characteristics, electrical characteristics and insulation characteristics may be remarkably deteriorated. Further, when exposed to a wet environment for a long period of time, there is a problem that the conductor pattern of the flexible printed circuit board is corroded, and there is a risk that problems such as disconnection and short circuit may occur.

  The present invention has been made in view of such points, and has high waterproofness while maintaining flexibility, has excellent durability even in a wet environment, and can be easily manufactured to improve productivity. It aims at providing the flexible flat harness which can be manufactured, and its manufacturing method.

  The flexible flat harness according to the present invention includes a flexible printed circuit board having a conductor pattern formed on an insulating film, and an elastic protective member having a waterproof property covering an outer peripheral surface excluding an end of the flexible printed circuit board. Features.

  By configuring the flexible flat harness according to the present invention as described above, the outer peripheral surface of the flexible printed board having a structure that easily absorbs water and corrodes easily in a wet environment is covered with a waterproof elastic protective member. Therefore, the waterproof property is high while maintaining flexibility, and the durability can be excellent even in a wet environment.

  The elastic protection member is formed, for example, in the vicinity of the end of the flexible printed circuit board as a waterproof plug having a shape that closes the insertion hole of the connector housing into which the end of the flexible printed circuit board is inserted. In addition, the waterproof plug includes a locking claw for preventing removal that engages with a locking piece formed inside the insertion hole of the connector housing, for example. Further, the flexible printed circuit board has, for example, a locking hole that engages with a lance formed in the connector housing at an end portion.

  The elastic protection member may be configured to include an integrally formed fixing clip for attaching and fixing the flexible printed board to the fixing member at a predetermined position on the flexible printed board. In addition, the elastic protection member may be configured to include a separate fixing clip that is insert-molded to attach and fix the flexible printed circuit board to the fixing member at a predetermined position on the flexible printed circuit board. Good. The elastic protection member is made of rubber or elastomer.

  The manufacturing method of the 1st flexible flat harness which concerns on this invention is a manufacturing method of the flexible flat harness formed by arranging the planar conductor which has flexibility, Comprising: The conductor pattern was formed on the insulating film A step of sandwiching a flexible printed circuit board by a movable pin from the thickness direction in the mold having a space for molding the outer shape of the flexible flat harness and placing the flexible printed circuit board in a floating state in the space; Filling the space with an insulating resin that forms a waterproof elastic protective member covering the outer peripheral surface of the flexible printed circuit board to form the outer shape of the flexible flat harness; and pulling out the movable pin from the space And filling the hole with the insulating resin to fill the hole. The features.

  The manufacturing method of the 2nd flexible flat harness which concerns on this invention is a manufacturing method of the flexible flat harness formed by juxtaposing the planar conductor which has flexibility, Comprising: The conductor pattern was formed on the insulating film A step of temporarily fixing the flexible printed circuit board with a fixing component disposed in a state of floating in the space of the mold having a space for molding the outer shape of the flexible flat harness, and an outer periphery of the flexible printed circuit board when cured And a step of forming an outer shape of the flexible flat harness by filling the space with an insulating resin that constitutes a waterproof elastic protection member that covers the surface together with the fixed component.

  The manufacturing method of the 1st and 2nd flexible flat harness which concerns on this invention is waterproofing the outer peripheral surface of the flexible printed circuit board of the structure which is easy to absorb and corrode easily in a to-be-watered environment by comprising as mentioned above. A flexible flat harness having a structure covered with an elastic protective member having a high resistance can be easily manufactured, so that the production of a flexible flat harness that is highly waterproof and has excellent durability even in a wet environment while maintaining flexibility Can be improved.

  According to the present invention, while maintaining the flexibility of the flexible flat harness, the waterproof property is high and the durability is excellent even in a wet environment, and it can be easily manufactured and the productivity can be improved.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a perspective view showing an example of a harness with a waterproof connector using the flexible flat harness according to the first embodiment of the present invention in a partially exploded state. 2 is a cross-sectional view taken along the line A-A ′ of FIG. 1, and FIG. 3 is a cross-sectional view taken along the line B-B ′ of FIG. 1.

  As shown in FIG. 1 to FIG. 3, the waterproof connector-equipped harness 1 includes a flexible flat harness 10 and a plurality of waterproof connectors 91, 92, and 93 that are attached to a terminal portion of the flexible flat harness 10. The flexible flat harness 10 includes a flexible printed circuit board 20 and a waterproof elastic protection member 30 that covers the outer peripheral surface of the flexible printed circuit board 20 except for an end portion thereof.

  The flexible printed circuit board 20 includes an insulating film 21 having insulating properties made of, for example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), polyolefin (PO), liquid crystal polymer (LCP), and the like (FIGS. 2 and 2). 3), a plurality of wirings 22 made of a conductor pattern made of gold, silver, copper, carbon, or the like are formed.

  The flexible printed circuit board 20 has a structure in which the insulating film 21 and the wiring 22 are further covered with a cover lay 23 made of a synthetic resin having electrical insulation. In addition, when the flexible printed circuit board 20 is a structure which has the wiring 22 on both surfaces of the insulating film 21, the coverlay 23 is formed so that the insulating film 21 and the wiring 22 of both surfaces may be covered, respectively.

  On the other hand, the waterproof connectors 91 to 93 are made of, for example, a resin molded member, and have insertion holes 91a, 92a, and 93a into which the ends of the flexible flat harness 10 are inserted on the rear end side, and other connectors (see FIG. (Not shown) has a connector fitting hole 95 into which the wiring provided in another connector and the wiring 22 of the flexible printed board 20 of the flexible flat harness 10 are electrically connected inside.

  In addition, the insertion holes 91a to 93a of the waterproof connectors 91 to 93 are formed with locking pieces 99 for engaging waterproof plugs 31, 32, and 33 of the elastic protection member 30 described later, respectively, and connector fitting. The holes 95 are each provided with a lance 94 (see FIG. 3) for locking and fixing the terminal portion of the flexible printed circuit board 20. Further, each waterproof connector 91 to 93 is provided with an engaging portion 96 for engaging with a locking piece (not shown) provided on another connector to prevent the connectors from coming off. .

  The flexible printed circuit board 20 is in a state in which the coverlay 23 is removed and the wiring 22 is exposed at each terminal portion. For example, the flexible printed circuit board 20 is connected to connection terminals (not shown) provided inside the waterproof connectors 91 to 93. It is configured so that it can be easily electrically connected or the exposed wiring 22 can be used as it is instead of the connection terminal. Further, in the vicinity of both ends in the short-side direction of each terminal portion of the flexible printed circuit board 20 is engaged with a lance 94 formed inside each waterproof connector 91 to 93 for positioning the terminal portion within the connector. Locking holes 24 are respectively formed.

  The elastic protection member 30 is made of, for example, rubber (silicon rubber, NBR, EPDM, fluororubber, chloroprene, etc.), an elastomer, and the like. It consists of a structure covered with a state. The elastic protective member 30 is formed with waterproof plugs 31 to 33 each having a shape for closing the insertion holes 91a to 93a of the waterproof connectors 91 to 93 into which the terminal portions are inserted in the vicinity of the terminal portions of the flexible printed circuit board 20. Become.

  Each of the waterproof plugs 31 to 33 includes, when inserted into the waterproof connectors 91 to 93, bowl-shaped water-stopping pieces 31a, 32a, and 33a that are in close contact with the inner wall surfaces of the respective insertion holes 91a to 93a with a predetermined pressure, and the respective insertion holes. The recesses 31c, 32c, 33c (only 31c shown) into which the locking pieces 99 formed at predetermined positions inside 91a to 93a are fitted and the wall surfaces of the locking pieces 99 on the connector fitting hole 95 side are waterproofed. Locking claws 31b, 32b, and 33b (only 31b shown) are provided for preventing the plugs 31 to 33 from coming out of the insertion holes 91a to 93a (that is, the terminal portions of the flexible printed circuit board 20). It is configured.

  As described above, the insertion holes 91 a to 93 a of the waterproof connectors 91 to 93 are closed by the waterproof plugs 31 to 33 provided in the elastic protection member 30 of the flexible flat harness 10. A structure in which moisture does not enter the connector fitting hole 95 side from the insertion holes 91a to 93a side is realized.

  In the waterproof connector-equipped harness 1 configured as described above, the flexible printed circuit board 20 is covered with the elastic protective member 30 having waterproof properties and in the vicinity of the terminal portion inserted into the waterproof connectors 91 to 93. Water is stopped by the waterproof plugs 31 to 33 of the elastic protection member 30.

  For this reason, for example, when the insulating film 21 of the flexible printed circuit board 20 is made of polyimide (PI), the water absorption is about 1.3 to 2.9%, and is made of polyethylene terephthalate (PET). However, in the flexible flat harness 10 of this example, the flexible printed board 20 does not absorb water.

  In addition, when the insulating film 21 of the flexible printed circuit board 20 is made of polyimide (PI), the elongation is about 45 to 80%, and when it is made of polyethylene terephthalate (PET), about 120%. However, in the flexible flat harness 10 of this example, since the elastic protective member 30 is made of a material excellent in elongation (elongation rate of about 500%), the flexibility is not significantly impaired as compared with the case of only PI or PET.

  Thereby, even if it is a case where the harness 1 with a waterproof connector of this example is used in the wet environment which is exposed to water, the flexible printed circuit board 20 which is easy to absorb water and corrode is covered with the elastic protective member 30. Therefore, high waterproofness and excellent durability can be realized while maintaining the flexibility of the harness.

  4 and 5 are explanatory views for enlarging and explaining a part of the flexible flat harness 10 in the waterproof connector-equipped harness 1. Although the waterproof connector-equipped harness 1 can be applied to the wet environment as described above, in such a wet environment, the attachment tape is usually attached to the fixing member to which the waterproof connector-equipped harness 1 is attached. In the case of mounting by, for example, the mounting stability may not be maintained (that is, the mounting tape may be peeled off).

  For this reason, in the harness 1 with waterproof connector of this example, as shown in FIG. 4, for example, the elastic protection member 30 of the flexible flat harness 10 is fixedly attached to the fixing member at a predetermined position on the flexible printed circuit board 20. It may be configured to include a fixing clip 40 for this purpose.

  The fixing clip 40 is integrally formed when the elastic protection member 30 is formed, for example, and is disposed on the base portion 41 that protrudes in a cylindrical shape from the surface of the elastic protection member 30 and on the distal end side of the base portion 41. An umbrella-shaped tip portion 42 inserted into a hole (not shown) provided in the fixing member is provided.

  If the fixing clip 40 is provided on the elastic protection member 30 of the flexible flat harness 10 as described above, the flexible protective substrate 30 and the flexible printed circuit board 20 can be easily attached to the fixing member, and the distal end portion 42 is provided. Since it is hooked and fixed in the hole of the fixing member, the mounting stability can be improved even in a wet environment.

  In place of the fixing clip 40 integrally formed with the elastic protection member 30, the elastic protection member 30 of the flexible flat harness 10 is elastically protected at a predetermined position on the flexible printed circuit board 20, as shown in FIG. The fixing clip 50 which consists of the resin molding member etc. which were shape | molded separately from the member 30 may be provided and comprised.

  The fixing clip 50 is, for example, insert-molded when the elastic protection member 30 is formed. The rectangular base portion 51 is disposed inside the elastic protection member 30 and a part thereof is exposed on the surface, and the base portion. 51, a pressing piece 52 having elasticity for pressing an opening peripheral portion of a hole portion (not shown) provided in the fixing member, and a central portion of the pressing piece 52, and is inserted into the hole portion. And an umbrella-shaped tip 53.

  If the fixing clip 50 is provided on the elastic protective member 30 of the flexible flat harness 10 as described above, it is easy to attach the flexible printed circuit board 20 to the fixing member together with the elastic protective member 30 as in the case of the fixing clip 40. Since the presser piece 52 is attached and fixed in a state of pressing the opening peripheral edge of the hole while the tip 53 is caught in the hole of the fixing member, the mounting stability is improved even in a wet environment. be able to.

  FIG. 6 is a flowchart showing an example of a manufacturing process of the flexible flat harness used in the above-described harness 1 with waterproof connector. FIG. 7 is a process explanatory diagram for explaining a part of the manufacturing process in the flowchart of FIG. 6. As shown in FIG. 6, the flexible flat harness 10 used for the harness 1 with a waterproof connector is manufactured in the following procedures.

  First, the wiring 22 is formed on the insulating film 21 in advance to cover the cover lay 23, and the flexible printed circuit board 20 formed in a desired shape is a mold provided with a space for molding the outer shape of the elastic protection member 30. It arrange | positions in space (step S101). That is, as shown in FIG. 7A, in the above step S101, the upper mold 101 and the lower mold 102 are respectively separated in the space 103 formed by combining the upper mold 101 and the lower mold 102. The flexible printed circuit board 20 is held between the movable pins 110 movably provided in the space 103 so that the flexible printed circuit board 20 floats in the air in the space 103.

  Next, an insulating resin material such as rubber or elastomer constituting the elastic protection member 30 is filled so as to fill the space 103 (step S102), and the elastic protection member 30 is formed by injection molding. Then, as shown in FIG. 7B, when the material filled in the space 103 is cured, the movable pins 110 sandwiching the flexible printed circuit board 20 are moved in the outward direction of the space 103 indicated by arrows in the drawing. At this time, the hole 110a in which the surface of the flexible printed circuit board 20 is exposed without forming the elastic protection member 30 is formed at the position where the movable pin 110 is in the space 103.

  In such a state where the hole 110a is formed, moisture can enter the flexible printed circuit board 20 when the flexible flat harness 10 is used in a wet environment. Finally, the movable pin 110 is moved. Then, the hole 110a in the space 103 is filled again with the material constituting the elastic protection member 30 to fill the hole 110a (step S103), and the outer periphery of the flexible printed circuit board 20 as shown in FIG. The surface is completely covered with the elastic protection member 30. Thereby, the flexible flat harness 10 which has the flexible printed circuit board 20 in the inside of the elastic protection member 30, and has high waterproofness can be manufactured.

  The waterproof plugs 31 to 33 of the elastic protection member 30 formed in the vicinity of the terminal portion of the flexible printed circuit board 20 of the flexible flat harness 10 are the outer shapes of the waterproof plugs 31 to 33 in the upper mold 101 and the lower mold 102, respectively. If spaces (not shown) for molding the same are formed in the same manner, and the material constituting the elastic protection member 30 is filled in step S102, these spaces are also filled with the material. It is possible to integrally mold with the elastic protection member 30.

  In addition to manufacturing the flexible flat harness 10 by disposing the flexible printed circuit board 20 in the space 103 using the movable pin 110 described above, the flexible printed circuit board 20 may be manufactured as follows, for example.

  FIG. 8 is a process explanatory diagram for explaining a part of the manufacturing process of the flexible flat harness according to the second embodiment of the present invention. That is, as shown in FIG. 8A, when the flexible printed circuit board 20 is arranged in step S101, the fixed component 120 is previously placed in the space 103 formed by the upper mold 101 and the lower mold 102. The fixed flexible printed circuit boards 20 </ b> A, 20 </ b> B, and 20 </ b> C are arranged together with the fixed component 120 and arranged in a state of floating in the air in the space 103.

  In step S <b> 102, the material constituting the elastic protection member 30 is filled in the space 103, and the outer peripheral surfaces of the flexible printed boards 20 </ b> A to 20 </ b> C are covered with the elastic protection member 30 together with the fixed components 120. Thereby, the flexible flat harness 10 which has flexible printed circuit boards 20A-20C in the inside of the elastic protection member 30, and has high waterproofness can be manufactured similarly.

  If the flexible flat harness 10 is manufactured by the manufacturing process as described above, even if the waterproof connector-equipped harness 1 using the flexible flat harness 10 is used in a wet environment where it is exposed to water. Since the flexible printed circuit board 20 that is easily absorbed or corroded is not covered with the elastic protective member 30 and exposed, the flexible flat harness 10 that realizes high waterproofness and excellent durability while maintaining the flexibility of the harness. Can be easily manufactured. Thereby, productivity of the flexible flat harness 10 which has waterproofness can be improved.

  INDUSTRIAL APPLICATION This invention is useful for the technique which uses the flexible flat harness comprised by a flexible printed circuit board etc. in the to-be-watered environment exposed to water.

It is a perspective view showing the example of the harness with a waterproof connector using the flexible flat harness concerning a 1st embodiment of the present invention in the state where a part was disassembled. It is A-A 'sectional drawing of FIG. It is B-B 'sectional drawing of FIG. It is explanatory drawing for magnifying and explaining a part of the flexible flat harness. It is explanatory drawing for magnifying and explaining a part of the flexible flat harness. It is a flowchart which shows the example of the manufacturing process of the flexible flat harness. It is process explanatory drawing for demonstrating a part of the manufacturing process. It is process explanatory drawing for demonstrating a part of manufacturing process of the flexible flat harness which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Harness with waterproof connector, 10 ... Flexible flat harness, 20 ... Flexible printed circuit board, 21 ... Insulating film, 22 ... Wiring, 23 ... Coverlay, 24 ... Locking hole, 30 ... Elastic protection member, 31-33 ... Waterproofing Stopper, 40, 50 ... Clip for fixing, 91-93 waterproof connector.

Claims (10)

A flexible printed circuit board having a conductor pattern formed on an insulating film;
A flexible flat harness comprising: an elastic protective member having waterproofness covering an outer peripheral surface excluding an end of the flexible printed circuit board.   The said elastic protective member comprises the waterproof plug of the shape which plugs up the insertion hole of the connector housing in which the edge part of this flexible printed circuit board is inserted in the edge part vicinity of the said flexible printed circuit board. Item 15. The flexible flat harness according to Item 1.   The flexible flat harness according to claim 2, wherein the waterproof plug has a locking claw for preventing removal that engages with a locking piece formed inside an insertion hole of the connector housing.   4. The flexible flat harness according to claim 2, wherein the flexible printed circuit board has a locking hole that engages with a lance formed in the connector housing at an end portion. 5.   The said elastic protection member is provided with the clip for fixation integrally formed for attaching and fixing the said flexible printed circuit board with respect to a fixing member in the predetermined position on the said flexible printed circuit board. The flexible flat harness according to any one of 4.   The elastic protection member includes a separate fixing clip that is insert-molded to attach and fix the flexible printed circuit board to a fixing member at a predetermined position on the flexible printed circuit board. Item 5. The flexible flat harness according to any one of Items 1 to 4.   The flexible flat harness according to claim 1, wherein the elastic protection member is made of rubber or elastomer. A method for producing a flexible flat harness comprising a planar conductor having flexibility,
A state in which a flexible printed board having a conductor pattern formed on an insulating film is sandwiched by a movable pin from the thickness direction in the mold having a space for molding the outer shape of the flexible flat harness and floats in the air in the space A process of arranging in
Filling the space with an insulating resin that forms a waterproof elastic protection member that covers the outer peripheral surface of the flexible printed circuit board when cured, and forming the outer shape of the flexible flat harness; and
And a step of pulling out the movable pin from the space and filling the hole with the insulating resin to fill the hole. A method for producing a flexible flat harness comprising a planar conductor having flexibility,
A step of temporarily fixing a flexible printed circuit board having a conductor pattern formed on an insulating film by a fixing component disposed in a floating state in the space of a mold having a space for molding the outer shape of the flexible flat harness; and
Filling the space with an insulating resin that forms a waterproof protective member that covers the outer peripheral surface of the flexible printed circuit board together with the fixed component when cured, and forming the outer shape of the flexible flat harness. A method for producing a flexible flat harness, characterized in that:   The method for manufacturing a flexible flat harness according to claim 8, wherein the elastic protection member is made of rubber or elastomer.

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