KR20100135054A - Connecting structure for flexible printed circuit board - Google Patents

Abstract

PURPOSE: The syndetic structure of the flexible printed circuit board transfers the electric signal in the state adamantly connected with the connection unit of the flexible printed circuit board and contacting portion of the PCB(Printed Circuit Board). CONSTITUTION: The conductivity pole(41) including the conductive powder is formed in the connection unit(11) of the flexible printed circuit board. PCB comprises the contacting portion(15) connected with the conductivity pole. In PCB, the guide pin coping with the guide hole and is inserted is formed. The retractor(34) pressurizes the upper end of the connection unit.

Description

Connecting Structure for Flexible Printed Circuit Board

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection structure of a flexible circuit board. In particular, a conductive pole is formed in a connection portion of a flexible circuit board, and the connection structure and silicon of a flexible circuit board connected to a hard printed circuit board (HPC) and fixed by a locking device. The connection structure of a flexible circuit board which connects the connection part of a flexible circuit board and a hard PCB using the PCR socket of a material, and is fixed by a locking device.

In general, a flexible printed circuit board is used to connect a hard PCB and other components in a small electronic product such as a mobile communication terminal. Unlike general hard PCB, flexible circuit board is not made of rigid material of board but is made of flexible material.

Therefore, when the flexible printed circuit board is used, a cable for electrical connection is not required separately, and a separate circuit can be implemented on the flexible printed circuit board, and it takes up less space. In addition, for example, when connecting a hard PCB and a display unit in a mobile communication terminal, the flexible circuit board is widely used because the substrate shape may be bent and deformable.

Figure 1a is a front view showing a main body and a connection portion of a typical flexible circuit board, Figure 1b is a cross-sectional view of the internal structure of the socket to which the connection portion of the flexible circuit board according to the prior art and Figure 1c is a front view of a hard PCB.

Hereinafter, a connection structure of a conventional flexible circuit board will be described with reference to FIGS. 1A, 1B, and 1C.

The flexible circuit board 10 has a connection portion 11 inserted into a connector 18 connected by a contact portion 15 and a connection terminal 14 of the hard PCB 19 to transmit an electrical signal.

The plated data line 13 is formed on the surface of the connection portion 11. The data line 13 is planarly connected to the data pin 16 of the connector 18. Therefore, there is a problem that the connection is deformed or separated by external impact.

In addition, the conventional connector 18 has a problem that the thickness and weight of the connector increases due to the metallic data pin 13 enters into the cover 17 made of a plastic material.

In order to solve the above problems, the present invention transmits an electrical signal in a state where it is firmly connected to a contact portion of a flexible circuit board and a contact hole of a hard printed circuit board (Hard PCB), and is applied to various electronic products. An object of the present invention is to provide a connection structure of a flexible circuit board of a new concept that enables ultra slim and ultra light weight of electronic products.

In order to achieve the above object, in the present invention, a conductive pole is formed at a connection portion located at the distal end of a conventional flexible circuit board. It is also possible to form the conductive poles on one or both surfaces of the connection part.

The conductive pole refers to a cylindrical material having a length made of a conductive powder or a conductive mixture in which a silicon material for sintering is mixed with the conductive powder. In particular, the conductive powder is preferably made of a conductive mixture in which the sintered silicon material is mixed, which is connected to the conductive powders as a stroke occurs due to shrinkage of the silicon when the upper end of the connection part of the flexible circuit board is pressed by a locking device to be described later. This is because the conductive poles have conductivity, and the anti-elasticity of the contracted silicon improves the connection between the contact portion of the hard PCB and the connection portion of the flexible circuit board.

The conductive powder may be formed of any one of nickel powder, silver powder, and gold powder. In addition, it is preferable to use silver powder which is excellent in electroconductivity, but what is necessary is just to be able to provide electroconductivity without a special limitation.

A process of forming the conductive poles in the connection portion of the flexible circuit board will be described later.

In addition, a guide hole may be formed in the connection portion of the flexible circuit board together with the conductive pole. Two or more guide holes are preferably provided, and may be provided in an appropriate number as necessary. In addition, the hard PCB is provided with a guide pin inserted corresponding to the guide hole.

 The guide pin and the guide hole serve to connect the connection portion of the flexible circuit board and the contact portion of the hard PCB at the correct position.

Next, the conductive pole is connected to the contact portion of the hard PCB, and the conductive member is connected to the contact portion using a locking device which is fastened by the first and second fastening portions connected to the hard PCB. To prevent the fall of the pole.

One end of the locking device is connected to the first fastening part, and the other end is connected to the second fastening part so that the upper and lower parts of the structure may be pressurized to press the upper end of the connection part of the flexible circuit board. It is connected by a (hinge) and the other end may be formed in an openable structure that is fastened to the second fastening portion. However, it is of course possible to use other locking devices having the same function without being limited thereto.

In addition, the present invention uses a conventional flexible circuit board (plated data line is formed in the connection) as it is, while a PCR socket (Pressure Contact Rubber Socket) is inserted between the contact portion of the flexible circuit board and the hard PCB To enable the transmission of electrical signals and to provide a connection structure of a flexible circuit board connected by fastening of a locking device.

A PCR socket (Pressure Contact Rubber Socket) is a kind of contactor having a conductive pole containing conductive powder in a main panel made of an insulating silicone material, and the conductive pole is formed of a plurality of conductive powders. It is arranged inside the insulating silicon at a constant pitch.

The description of the conductive pole is replaced with the above-described bar, and the manufacturing process of the PCR socket will be described later.

Meanwhile, an upper end surface of the conductive pole is connected to the connection part, and a lower end surface is connected to the contact part. Next, the connection part, the conductive pawl, and the contact part are prevented from being separated from each other by using a locking device fastened to the first and second fastening parts connected to the hard PCB.

 In the main panel of the PCR socket, guide holes may be formed together with the conductive poles. Two or more guide holes are preferably provided, and may be provided in an appropriate number as necessary. The hard PCB is provided with guide pins inserted corresponding to the guide holes.

 The guide pin and the guide hole serve to connect the conductive pole and the contact portion at the correct position. The description of the locking device will be replaced with the above description.

In addition, the present invention is characterized in that it further comprises a mesh (mesh) to prevent the separation of the conductive powder forming a conductive pole of the PCR socket. Preferably, the mesh is formed of a conductive material. On the other hand, the mesh may be formed of a non-conductive material, the conductive material for filling the mesh may be inserted into the lattice hole of the mesh. The non-conductive material is characterized in that the polyester (PET). The grid hole refers to an empty space formed by a structure constituting the mesh in the mesh.

The mesh may prevent the conductive material, such as the conductive powder contained in the conductive pole, from falling off or wearing away, thereby enabling good conduction between the flexible circuit board and the hard PCB.

According to the present invention, the connection between the flexible printed circuit board and the hard PCB is maintained firmly and stable electricity supply is possible, and when the present invention is applied to various electronic products, the effect of enabling ultra slim and ultra light weight of electronic products is possible. There is.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible, even if shown on different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

Example  One

2A is a front view illustrating the formation of a conductive pole in a connection portion of a flexible circuit board according to the present invention, and FIG. 2B is a side view of FIG. 2A.

As illustrated in FIGS. 2A and 2B, the present invention provides a conductive pole corresponding to a data line 12 formed along a main body of the flexible printed circuit board 10 at a terminal connection portion 11 of the flexible printed circuit board 10. 20) is formed. It is also possible to form the conductive poles 20 on one side or through both sides of the connection part 11.

In the present invention, the conductive pole refers to a cylindrical structure having a length made of a conductive powder in which a conductive powder or a conductive powder is mixed with the conductive powder. In particular, the conductive powder is preferably made of a conductive mixture in which the sintered silicon material is mixed, which is connected to the conductive powders as a stroke occurs due to shrinkage of the silicon when the upper end of the connection part of the flexible circuit board is pressed by a locking device to be described later. This is because the conductive poles have conductivity, and the anti-elasticity of the contracted silicon reinforces the connection between the contact portion of the hard PCB and the connection portion of the flexible circuit board.

The conductive powder may be formed of any one of nickel powder, silver powder, and gold powder. It is preferable to use silver powder which is excellent in electroconductivity, but what is necessary is just to be able to provide electroconductivity without a restriction | limiting in particular.

A method of forming the conductive poles 20 in the connection portion 11 of the flexible circuit board will be described in the second embodiment to be described later.

Hereinafter, a first embodiment of the present invention relating to a connection structure of a flexible circuit board will be described.

3A is a side view illustrating a process of inserting a guide pin of a hard PCB into a guide hole of a flexible circuit board, and FIGS. 3B and 3C illustrate a connection structure of a flexible printed circuit board according to a first embodiment of the present invention. Side view.

Referring to FIG. 3A, a guide hole 30 is formed in the connection portion of the flexible circuit board together with the conductive pole 20. The guide hole 30 is preferably provided with two or more, and is provided in an appropriate number as necessary. In addition, the hard PCB is provided with a guide pin 31 inserted corresponding to the guide hole.

 The guide pin 31 and the guide hole 30 serve to connect the connection part 11 of the flexible circuit board and the contact part 15 of the hard PCB at the correct position.

Next, referring to FIG. 3B, a locking device connected to the conductive pole 20 to the contact part 15 of the hard PCB and fastened by the first fastening part 32 and the second fastening part 33 connected to the hard PCB. Departure from the conductive pole 20 connected to the contact portion 15 by using a (34).

One end of the locking device 34 is connected to the first fastening part 32, and the other end thereof is connected to the second fastening part 33 so as to press the upper and lower ends of the connection part 11 of the flexible circuit board. Move.

The locking device 34 may be manufactured by varying the area and thickness so as to press the upper end of the connection portion 11 sufficiently to be pressed. In addition, the locking device 34 is preferably made to sufficiently press the connection portion 11 so that the conductive pole 20 is connected to the contact portion 15 stably and energized.

The first fastening part 32 and the second fastening part 33 are fastened to each other when the locking device 34 is fastened so as to stably connect the connection part 11 to the contact part 15. The structure or the structure which strengthens the fastening of the locking device 34 using an elastic body is provided. However, various modifications can be made to the fastening means that is obvious to those skilled in the art.

Particularly, the conductive pole 20 is preferably made of a conductive mixture in which a sintered silicon material is mixed with the conductive powder. When the upper end of the connection part 11 of the flexible circuit board is pressed by the locking device 34, Conductive powders are connected as the stroke is generated by contraction so that the conductive poles 22 have conductivity, and the contact portion 15 of the hard PCB and the connection portion 11 of the flexible circuit board are connected due to the anti-elasticity of the contracted silicon. Because it can strengthen.

Referring to FIG. 3C, one end of the first fastening part 32 and the locking device 34 connected to the conductive pole 20 and connected to the hard PCB is connected to the contact part 15 of the hard PCB. Connected by The other end of the locking device 34 is fastened to the second fastening part 33 by moving the pivoting part 35 as an axis by being connected to the pivoting part 35.

When the other end of the locking device 34 is fastened to the second fastening part 33, the locking device uses a structure that is fastened so as not to be detached from the connection part 11 and the contact part 15, or an elastic body. It is a structure to strengthen the fastening of. However, various modifications can be made to the fastening means that is obvious to those skilled in the art.

Example  2

4 is a perspective view illustrating a PCR socket, and FIGS. 6A and 6B are side views illustrating a connection structure of a flexible circuit board according to a second embodiment of the present invention.

 According to the present invention, a PCR socket (Pressure Contact Rubber Socket) is inserted between the connection portion of the flexible circuit board and the contact portion of the hard PCB while using a conventional flexible circuit board (forming a plated data line). It provides an electrical signal transmission and provides a connection structure of a flexible circuit board connected by the fastening of the locking device.

In the present invention, a PCR socket (Pressure Contact Rubber Socket) is a kind of contactor having a conductive pole containing conductive powder on a main panel made of an insulating silicone material, and the conductive pole is composed of a plurality of pellets. It refers to the conductive powders arranged in the insulating silicon at a constant pitch.

The description of the conductive poles is replaced with the description of the first embodiment.

Hereinafter, a manufacturing process of the PCR socket 40 will be described with reference to FIG. 5.

Step S1: The protective film 50 is attached to the upper and lower surfaces of the main panel 43 made of an insulating silicone material. The length of the conductive pole 41 may be adjusted by adjusting the thickness of the protective film 50. Protective film 50 is applied to suppress the by-products generated in the subsequent hole processing to contaminate the main panel 43 to omit a separate polishing (Polishing) process. The material of the protective film is preferably made of synthetic resin, but there is no particular limitation as long as the material can serve as a protective film.

In step S2, laser drilling or mechanical drilling is performed to form the through hole 52. There is no particular limitation on the method of perforation, but as shown in FIG. 5, perforation using the laser hole processing 51 is preferable.

Laser hole processing is a device applied to form a fine line width in the semiconductor manufacturing process, because the line width of the beam can be reduced to less than 1 pm (pico meter). It is disclosed in Korean Patent Laid-Open Publication No. 2002-0022136 as an example of the device for this.

Step S3: The method for forming the conductive pole 41 by filling the conductive powder or the conductive mixture into the through hole 52 formed in the main panel 43 includes forming the conductive powder or the conductive mixture through the through hole 52 of the main panel 43. Various methods, such as pressurized filling into the inside), can be applied.

Step S4: Removing the protective film 41 to remove the by-products generated during the through-hole 52 processing. As a result, a PCR socket 40 is produced.

The manufacturing process of the above PCR socket may be applied to the formation of a conductive pole in the point portion of the flexible circuit board in the first embodiment. However, in the first embodiment, there is a difference in that the conductive poles 20 are formed in the connecting portion 11 of the flexible circuit board, not the main panel, as shown in FIG. 2A.

Next, referring to FIG. 6A, a guide hole 42 is formed in the main panel 43 of the PCR socket 40 together with the conductive pole 41. The guide hole 42 is preferably provided with two or more, and may be provided in an appropriate number as necessary. The hard PCB 19 includes a guide pin 31 inserted corresponding to the guide hole 42.

 The guide pin 31 and the guide hole 42 serve to connect the conductive pole 41 and the contact portion 15 of the hard PCB at the correct position.

Next, an upper end surface of the conductive pole 41 is connected to the connecting portion 11 of the flexible circuit board, and a lower end surface thereof is connected to the contact portion 15 of the hard PCB 19. Next, the connection part 11, the conductive pole 41, and the contact point using the locking device 34 fastened to the first fastening part 32 and the second fastening part 33 connected to the hard PCB 19. The parts 15 are prevented from being separated from each other.

One end of the locking device 34 is connected to the first fastening part 32, and the other end thereof is connected to the second fastening part 33 so as to press the upper and lower ends of the connection part 11 of the flexible circuit board. Move.

The locking device 34 may be manufactured by varying the area and the thickness so as to press the upper end of the connection portion sufficiently pressed. In addition, the locking device 34 preferably pressurizes the upper end of the connecting portion 11 of the flexible circuit board so that the conductive pole 41 is stably connected to the contact portion 15 and the connecting portion 11 and energized. .

The first fastening portion 32 and the second fastening portion 33 strongly fasten the fastening of the locking device by using a structure that is fastened by a fastening method or an elastic body when fastening the locking device 34 to be stably fastened. It becomes the structure to make. However, various modifications can be made to the fastening means that is obvious to those skilled in the art.

In particular, the conductive pawl 41 is preferably made of a conductive mixture in which a sintered silicon material is mixed with the conductive powder. When the upper end of the connection part 11 of the flexible circuit board is pressed by the locking device 34, Conductive powders are connected as the stroke is generated by contraction, so that the conductive poles 41 have conductivity, and due to the anti-elasticity of the contracted silicon, the conductive poles 41 and the flexible poles of the contact portion 15 of the hard PCB and the PCR socket are flexible. This is because the connection of the connecting portion 11 of the circuit board is strengthened.

Referring to FIG. 6B, one end of the first fastening part 32 and the locking device 34 connected to the conductive pole 41 of the PCR socket is connected to the contact part 15 of the hard PCB and is connected to the hard PCB. 35). The other end of the locking device 34 is coupled to the second fastening part 33 by moving the pivoting part 35 as an axis by the connection by the pivoting part 35.

When the other end of the locking device 34 is fastened to the second fastening part 33, the second fastening part 33 is connected to the connection part 11 of the flexible circuit board, the conductive pole 41, and the contact part 15. ) Is a structure that is fastened so as not to be separated from each other, or a structure that strongly tightens the locking device by using an elastic body. However, various modifications can be made to the fastening means that is obvious to those skilled in the art.

Example  3

7 is a cross-sectional view illustrating a state in which a mesh is attached to a conductive pole of a PCR socket according to a third embodiment of the present invention.

Referring to Figure 7, the present invention is characterized in that it further comprises a mesh (60) for preventing the separation of the conductive powder forming the conductive pole 41 of the PCR socket. Preferably, the mesh 60 is formed of a conductive material. On the other hand, the mesh 60 is formed of a non-conductive material, it may be characterized in that the conductive powder for filling the mesh is inserted into the grid hole of the mesh.

The mesh 60 may prevent the conductive material, such as the conductive powder, contained in the conductive pole 41 from being separated or worn out, thereby enabling good conduction between the flexible circuit board 10 and the hard PCB 19. .

The method of attaching the mesh 60 to the main panel 43 is not particularly limited, but the conductive pole 41 filled in the attachment surface of the mesh 60 and the inside of the through hole should be in contact with each other so as to be energized. .

After attaching the mesh 60 to the main panel 43, the mesh 60 attached to the main panel 43 is cut, and the mesh 60 is cut according to the conductive poles 41 disposed at minute intervals. In order to do this, it is preferable to use a laser cutting machine.

At this time, the pieces of the mesh 60 remaining attached to the main panel 43 in the cut state correspond to the conductive poles 41 one by one to cover the conductive poles 41 so that the conductive poles 41 are adjacent to each other. Do not allow electrical connections.

When the mesh 60 is formed of a conductive material, the conductive mesh 60 may be attached as described above. However, when the mesh 60 is formed of a non-conductive material such as polyester, the conductive powder for mesh filling is applied onto the mesh 60 attached to the main panel 43, and the conductive powder for filling the mesh The coated mesh 60 is pressed using a press to insert and adhere the conductive powder for mesh filling into the lattice hole of the mesh 60.

Meanwhile, the surface of the mesh 60 is filled with conductive powder for mesh filling so that the surfaces of the conductive pole 41 and the mesh 60 may be electrically connected through the mesh filling conductive powder filled in the lattice holes of the mesh 60. It is preferable to apply | coat and compress sufficiently to the.

The reason why the non-conductive mesh 60 is made of polyester in particular is;

In mechanical properties, the tensile strength of polyester is 20kgf / mm or more, and considering the cross-sectional area at break, it is comparable to mild steel and the mechanical strength is maintained in practical range from low temperature (-70 ℃) to high temperature (150 ℃). This is because the stiffness is large, and the tensile modulus of elasticity is 400 kgf / mm, which is higher than cellophane.

This is because the melting point is high at 260 ° C, the heat shrinkage rate is low at 1-2% at 170 to 180 ° C, and the decrease in elongation rate due to continuous heating is also low.

In addition, in moisture resistance and water resistance, the water absorption of polyester is low as 0.2-0.4% even after 24 hours immersion, and is due to EO, which has a very small change in numerical value and mechanical properties due to moisture absorption.

In addition, it is because electrical insulation properties are large, and excellent heat resistance and moisture resistance are combined to exhibit ideal electrical insulation properties. However, of course, other non-conductive materials can also be used as the mesh.

On the other hand, the conductive powder for mesh filling may be a metal powder such as silver powder, gold powder, nickel powder, copper powder, etc., it is preferable that the silver powder excellent in conductivity.

Thereafter, the conductive poles 41 adjacent to each other using a laser cutter are not electrically connected through the mesh 60.

The mesh 60 may be attached to any one side of the upper and lower surfaces of the main panel 43 or may be attached to both the upper and lower surfaces of the main panel 43.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art may make various modifications, changes, and substitutions without departing from the essential characteristics of the present invention. Will know.

1A is a front view illustrating a main body and a connecting portion of a general flexible printed circuit board.

1B is a cross-sectional view of an internal structure of a socket to which a connection portion of a flexible circuit board according to the prior art is connected.

1C is a front view of a hard PCB.

Figure 2a is a front view showing that the conductive pole is formed in the connection portion of the flexible circuit board according to the present invention.

2B is a side view of FIG. 2A;

3A is a side view illustrating a process of inserting a guide pin of a hard PCB into a guide hole of a connection portion of a flexible circuit board.

3B is a side view showing a connection structure of a flexible circuit board according to a first embodiment of the present invention.

3C is a side view showing a connection structure of a flexible circuit board according to a first embodiment of the present invention.

4 is a perspective view showing a PCR socket.

Figure 5 is a schematic diagram showing a cross section of the PCR socket under construction to explain the manufacturing process of the PCR socket.

6A is a side view showing a connection structure of a flexible circuit board according to a second embodiment of the present invention.

6B is a side view showing a connection structure of a flexible circuit board according to a second embodiment of the present invention.

6C is a perspective view illustrating a three-dimensional shape of the connection structure of the flexible circuit board according to the second embodiment of the present invention.

7 is a cross-sectional view showing a state in which a mesh is attached to a conductive pole of a PCR socket according to a third embodiment of the present invention.

Claims (17)

In the connection structure of a flexible circuit board, A flexible circuit board on which a conductive pole including conductive powder is formed on the connection portion; And And a Hard PCB (Hard Printed Circuit Board) having a contact portion connected to the conductive poles. The method of claim 1, And a locking device for pressing the upper end of the connection part to prevent the conductive pole from being separated from the contact part. The method of claim 2, And the contact portion is a contact portion provided with a groove into which the conductive pole can be inserted. The method of claim 2, The connection part includes a guide hole for connecting the conductive pole and the contact part at a predetermined position, and a guide pin inserted in the hard PCB corresponding to the guide hole is formed. Connection structure of flexible circuit board. The method of claim 2, Wherein the conductive pole is a connection structure of the flexible circuit board, characterized in that any one of the one side or the penetrating formed on both sides. In the connection structure of a flexible circuit board, A flexible circuit board having plated data lines formed thereon; A hard PCB having a contact portion connected to the connection portion; And A conductive pole containing a conductive powder is inserted into the main panel of an insulating material and formed, the connection structure of a flexible circuit board comprising a PCR socket (Pressure Contact Rubber Socket) provided between the contact portion and the contact portion. . The method of claim 6, The connection structure of the flexible circuit board further comprises a locking device for preventing the contact portion connected to the bottom surface of the conductive pole and the connection portion connected to the top surface of the conductive pole from being separated from the PCR socket. . The method of claim 7, wherein The main panel includes a guide hole for connecting the conductive pole and the contact portion at a predetermined position, and the hard PCB includes a guide pin inserted into the guide hole to correspond to the guide hole. . The method of claim 7, wherein A flexible circuit further comprising a mesh attached to the main panel while covering at least one or more of the top or bottom surfaces of the conductive poles to prevent separation of the conductive powder forming the conductive poles. Board connection structure. The method according to claim 2 or 7, The locking device is connected to the first fastening portion and the second fastening portion connected to the hard PCB to press the upper end of the connecting portion, characterized in that the connection structure of the flexible circuit board. The method of claim 10, One end of the locking device is connected by the first fastening portion and the hinge (hinge) and the other end of the connection structure of the flexible circuit board is fastened at the second fastening portion. The method of claim 9, The mesh is connected structure of a flexible circuit board, characterized in that formed of a conductive material. The method of claim 9, The mesh is formed of a non-conductive material, the connection structure of the flexible circuit board, characterized in that the conductive powder for mesh filling is inserted into the grid hole of the mesh. The method of claim 13, The non-conductive material is a connection structure of a flexible circuit board, characterized in that the polyester (PET). The method according to claim 1 or 6, Wherein the conductive pole is a connection structure of a flexible circuit board, characterized in that made of a conductive mixture of the silicon material for sintering and the conductive powder. The method of claim 6, The main panel is a connection structure of a flexible circuit board, characterized in that the silicon. The method of claim 15, The conductive powder is any one of nickel powder, silver powder and gold powder connection structure of the flexible circuit board.

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