TWI583277B - Flexible cable manufacturing method - Google Patents

Description

Flexible cable manufacturing method

The present invention relates to a method of manufacturing a flexible cable; and more particularly to a method of manufacturing a flexible cable that can be applied to high frequency signal transmission.

Flexible Flat Cable (Flexible Flat Cable), referred to as flexible cable or FFC, is a data cable structure that is made of PET insulation material and a plurality of tinned flat copper wires pressed through a high-tech automation equipment production line. The flexible cable is a signal transmission component, which has the advantages of arbitrary deflection and high signal transmission capability, and thus is widely used in many electronic products.

Generally, the conventional flexible cable is subdivided into a three-layer structure, which is formed by stacking the upper insulating layer, the wiring layer and the lower insulating layer in order from top to bottom. The upper and lower insulating layers are made of PET material, and the wires are made. The layer comprises a plurality of flat copper wires arranged in parallel with each other, and the ends thereof are exposed at both ends of the flexible cable to form a conductive contact, and the conductive contacts of the flexible cable can be directly connected to the cable connector. Alternatively, the conductive contacts of the flexible cable are attached to the insulative housing, and then the upper and lower iron shells are assembled on the insulative housing, so that the connector structure with the flexible contact wires as the terminals can be formed.

Due to the increasing demand for electronic communication, the signal transmission speed requirements of electronic devices are becoming higher and higher, and the development of electronic technology tends to be high-frequency signals and high current transmission. lose. Therefore, the requirements for the electrical characteristics of the transmission line have also been improved. Although coaxial cables have been developed for use in electronic products for high-frequency signal transmission, their production costs and high prices do not meet the low-cost requirements of consumers. Therefore, some operators have tried to replace the coaxial cable with a soft flat cable, but the electrical characteristics of today's soft flat cable cannot meet the requirements of high frequency use. Therefore, how to develop a transmission line which is low in cost and can meet the signal transmission requirement at the time of high frequency use is a problem to be solved by the present invention.

Although the soft flexible cable has the advantages of arbitrarily flexing and high signal transmission capability, it is widely used in many electronic products. However, in today's electronic technology development tends to use high-frequency signal transmission environment, the conventional soft cable The signal transmission cannot meet the characteristics of the high-frequency use, so it cannot meet the market demand.

The flexible cable manufacturing method of the present invention comprises the steps of: providing a wire providing step of providing a plurality of first wires and second wires, wherein each of the first wires is a flat metal wire, and each of the second wires Is a flat metal wire covering an insulating film; a selective wiring step, wherein the first wire and the second wire are selectively arranged to be arranged in parallel with each other to arrange one of the wire layers; and a thermocompression In the wire step, the wire layer is heat-compressed from above to below by a second insulating layer and a first insulating layer to form a flexible wire.

The flexible wiring manufacturing method provided by the present invention utilizes an insulating film coated on the periphery of a flat metal wire for transmitting a high-frequency signal, and the flexible film can be reduced because the insulating film can reduce the dielectric constant. The electrical characteristics required for high-frequency use can solve the problem that the conventional flexible cable cannot meet the requirements of high-frequency use and can not meet the market demand.

1‧‧‧Flexible cable

11‧‧‧First insulation

12‧‧‧First layer

13‧‧‧Wire layer

131‧‧‧flat metal wire

132‧‧‧Signal line

133‧‧‧ Grounding wire

134‧‧‧Insulation film

135‧‧‧Contacts

14‧‧‧Second layer

15‧‧‧Second insulation

21‧‧‧Wire supply steps

22‧‧‧Select wiring steps

221‧‧‧ Signal definition steps

222‧‧‧Select configuration steps

223‧‧‧ Identification difference steps

23‧‧‧Processing and removing steps

24‧‧‧Check and discriminate steps

25‧‧‧Hot press line step

The first figure is a perspective view of the flexible cable of the present invention.

The second figure is a partial cross-sectional view of the flexible cable of the first figure.

The third figure is a schematic flow chart of the manufacturing method of the flexible cable of the present invention.

The fourth figure is a schematic flow chart of the selection wiring step of the flexible wiring manufacturing method of the present invention.

Referring to the first to second embodiments, a flexible cable structure of the present invention includes a first insulating layer 11, a first adhesive layer 12, and a first flexible layer. The wire layer 13, a second adhesive layer 14, and a second insulating layer 15.

The first adhesive layer 12 is formed on the first insulating layer 11. In the embodiment, the first adhesive layer 12 is made of insulating glue, and the first insulating layer 11 is polyethylene terephthalate (PET). The layer, the wire layer 13 is disposed on the first adhesive layer 12, the wire layer 13 includes a plurality of flat metal wires 131 arranged in parallel with each other, wherein the flat metal wires 131 comprise a plurality of signals for transmitting signals. The line 132 and the plurality of grounding lines 133 for grounding. Since the signal line 132 is used to transmit high frequency signals in the present embodiment, the insulating film 134 is coated on the periphery of the signal line 132 to protect the high frequency signal. The adhesive layer 14 is disposed on the wire layer 13, and the second insulating layer 15 is disposed on the second adhesive layer 14. The second adhesive layer 14 is made of insulating rubber, and the second insulating layer 15 is made of polyethylene terephthalate. Diester (PET) layer.

In the present embodiment, the insulating film 134 is made of a material having a low dielectric constant, such as a foamed insulating material, and the dielectric constant is usually between 1 and 3.5. The present invention utilizes this insulating material. The film 134 is wrapped around the periphery of the signal line 132 for transmitting the high frequency signal in the flat metal wire 131, thereby reducing the dielectric constant of the flexible cable 1 so as to conform to the power during high frequency use. The gas characteristic requirement can solve the problem that the conventional flexible cable cannot meet the requirements of high frequency use and can not meet the market demand. In addition, in the embodiment, the width of each of the flat metal wires 131 after processing is substantially between 0.25 mm and 0.7 mm, and the height thereof is between 0.022 mm and 0.1 mm. The thickness of the insulating film 134 is between 50 μm and 100 μm, so as to obtain a preferable low dielectric property requirement.

It should be noted that, in this embodiment, the ends of the plurality of flat metal wires 131 of the wire layer 13 of the flexible cable 1 are exposed to the second insulating layer 15 and the second adhesive layer 14 to form a plurality of connections. Point 135, the contacts 135 have a flat contact surface, so as to facilitate subsequent use with a connector (not shown). That is, in the embodiment, the insulating film 134 covering the periphery of the signal line 132 in the flat metal wire 131 is not exposed to the second insulating layer 15 and the second adhesive layer 14, so that the conductive effect can be formed. Point 135, in other words, the insulating film 134 is not completely covered to the end of the flat metal wire 131.

It can be understood that, in this embodiment, since the thickness of the insulating film 134 of the present invention is thin and conformally covers the flat signal line 132, the outer shape of the insulating film 134 is substantially hollow and flat. Therefore, it is advantageous to adhere to the thermocompression bonding of the first insulating layer 11 and the second insulating layer 15 without generating voids, and the electrical characteristics such as the impedance of the flexible wiring 1 are preferably improved. Therefore, in this embodiment, The thickness of the insulating film 134 must be smaller than the width of the signal line 132 so as to be conformally coated to form a flat shape. In addition, its appearance size is almost the same as the conventional flexible cable, but its electrical characteristics suitable for high-frequency signal transmission are far superior to the conventional flexible cable, so the flexible cable 1 of the present invention can be achieved without increasing The advantages of using space.

In addition, referring to the third figure, the present invention provides a manufacturing method of the flexible cable 1, the step comprising: a wire providing step 21, which provides a plurality of first wires and second wires In the present embodiment, the flat metal wire 131 is defined as a first wire, and the other flat metal wire 131 covered with the insulating film 134 is defined as a second wire; The first wire and the second wire are alternately arranged to be arranged in parallel with each other to arrange one of the wire layers 13; a processing and removing step 23, the processing and removing step 23 is to use the laser to shield the insulating film 134 on the second wire. Selectively removed to expose a portion of the other flat metal wire 131; and a thermocompression bonding step 25 of using a second insulating layer 15 and a first insulating layer 11 respectively to route the wire layer from above to below 13 is hot pressed and integrated to form a flexible cable 1.

In the present embodiment, the method of providing the second wire in the wire material providing step 21 includes a coating process step of conformally coating the insulating film 134 on the periphery of the other flat metal wire 131 to form the insulation. The process of the film 134 can be achieved by various different coating methods such as extrusion molding, film coating, or immersion coating. Therefore, the insulating film 134 is not limited to the other flat metal in the present invention. The manufacturing method of the periphery of the wire 131.

In addition, in the present embodiment, in order to expose the ends of the plurality of flat metal wires 131 of the wire layer 13 of the flexible wiring 1 to form a plurality of contacts 135, a processing is also performed after the wiring step 22 is selected. In the removing step 23, the processing and removing step 23 selectively removes the insulating film 134 on the second wire by means of laser processing. However, it is not limited thereto, and the mechanical processing method may be selected to remove part of the insulating film 134. The insulating film 134 is formed such that the insulating film 134 is not completely covered to the end of the flat metal wire 131, so that the contact 135 can be formed smoothly and is advantageous for automated mass production in terms of process.

It is worth mentioning that in order to confirm whether the laser has removed the insulating film 134 at a specific position on the second wire, it may further include an inspection and identification step 24 after the processing and removing step 23, the inspection and identification step 24 is An image sensor can be used to detect the second wire The appearance color of the specific position is significantly different from the appearance color of the second wire coated with the insulating film 134 and the second wire from which the insulating film 134 is removed, that is, the appearance color of both the insulating film 134 and the other flat metal wire 131. It is not the same, and therefore, based on this difference, it can be discriminated whether or not the insulating film 134 at a specific position on the second wire has been completely removed.

Referring to the fourth figure, in the embodiment, the method for selectively interleaving the plurality of first wires and the second wires in the selecting wiring step 22 includes: a signal defining step 221, which is based on the flexible cable 1 arranging a plurality of electronic signals to define an arrangement order; and a selection configuration step 222, selecting the corresponding first wire and second wire as the line layout configuration for transmission according to the arrangement order . It can be understood that the types of electronic signals to be transmitted by the flexible cable 1 include high frequency signals, general signals, ground signals and power signals, etc., and only the flat metal wires 131 for transmitting high frequency signals may be included therein. The insulating film 134 needs to be coated. Therefore, the number and layout of the first wire and the second wire are selected according to the type and arrangement order of the electronic signals transmitted by the flexible cable 1 in actual use.

It is worth mentioning that, in this embodiment, after the selecting configuration step 222 in the selecting wiring step 22, a identification distinguishing step 223 is further included, which is used to confirm the arrangement of the first wire and the second wire. The position and sequence conform to the type and arrangement order of the plurality of electronic signals to be transmitted by the flexible cable 1, to avoid the wire configuration error caused by human or other factors in the selection configuration step 222. In the identification distinguishing step 223, an image sensor can be used to detect the appearance color of the first wire and the second wire. Since the appearance colors of the first wire and the second wire are significantly different, the difference can be distinguished according to the difference. To confirm whether the arrangement position and order of the first wire and the second wire are correct.

It can be understood that in this embodiment, it can be manufactured in a continuous manner. The flexible cable 1 is connected and produced in an extension manner one after another, so as to form a cable belt having a plurality of flexible cables 1, and then the user can divide and draw an appropriate number according to the needs of the environment at the time. The flexible cable 1 is used, so that after the hot-pressing line step 24 of the present invention, a cutting step is included, which can cut the cable strip into a plurality of flexible cables 1 by using a cutter, The present invention facilitates automated mass production and reduces manufacturing costs, and also facilitates the user to use an appropriate number of flexible cables 1 from a full length of cable strip for use.

In summary, the flexible wiring manufacturing method provided by the present invention covers an insulating film on the periphery of a flat metal wire for transmitting a high-frequency signal, and the insulating film can reduce the dielectric constant characteristic, so that the surface can be flexed. The sex cable meets the electrical characteristics requirements for high-frequency use, thus solving the problem that the conventional flexible cable cannot meet the requirements of high-frequency use and can not meet the market demand.

The above detailed description is intended to be illustrative of a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and other equivalents and modifications may be made without departing from the spirit of the invention. Changes are intended to be included in the scope of the patents covered by the present invention.

21‧‧‧Wire supply steps

22‧‧‧Select wiring steps

23‧‧‧Processing and removing steps

24‧‧‧Check and discriminate steps

25‧‧‧Hot press line step

Claims (9)

A flexible cable manufacturing method, the method comprising: a wire providing step of providing a plurality of first wires and second wires, wherein each of the first wires is a flat metal wire, and each of the second wires Another flat metal wire encasing an insulating film, wherein the method of providing the second wires in the wire providing step comprises a coating process step of conformally coating the insulating film And a selective wiring step, wherein the first wire and the second wire are selectively disposed to be arranged in parallel with each other to arrange one of the wire layers; and a hot pressing step, The wire layer is heat-compressed from above to below by a second insulating layer and a first insulating layer to form a flexible wiring. The flexible wiring manufacturing method according to claim 1, wherein the insulating film has a thickness of between 50 μm and 100 μm. The flexible wiring manufacturing method according to claim 1, wherein the flat metal wire has a width of between 0.25 mm and 0.7 mm, and the flat metal wire has a height of between 0.022 mm and 0.1 mm. The flexible wiring manufacturing method according to claim 1, wherein the insulating film is made of a material having a low dielectric constant. The flexible wiring manufacturing method according to claim 1, wherein the insulating film has a dielectric constant of between 1 and 3.5. The method for manufacturing a flexible cable according to the first aspect of the patent application, wherein the method for selectively configuring the selected wiring step comprises: a signal defining step, which is based on the plurality of electronic signals to be transmitted according to the flexible cable The type defines an arrangement order; and a selection configuration step selects the corresponding first wire and the second wire as the line configuration for transmission according to the arrangement order. The method for manufacturing a flexible cable according to the first aspect of the invention, wherein the selecting the wiring step further comprises a step of distinguishing between the first wire and the second wire Both are to confirm whether the arrangement position and order of the first wire and the second wire are correct. The flexible wiring manufacturing method according to any one of claims 1 to 7, wherein after the selecting the wiring step, further comprising a processing and removing step, the processing and removing step is performed on the second wire The insulating film is selectively removed to expose a portion of the other of the flat metal wires. The method of manufacturing a flexible cable according to claim 8, wherein the processing and removing step further comprises an inspection and discrimination step, wherein the inspection and discrimination step is based on an appearance color of the insulating film and another of the flat metal wires. Differently, it is discriminated whether the insulating film at a specific position on the second wire has been removed.