JPH0542584Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Field of Industrial Application" The present invention relates to the structure of a terminal section inserted and connected to a connector as an external connection of a membrane keyboard switch. While adopting a double-sided flexible circuit board structure without using an epoxy resin reinforcing film, etc., it has the required contact pattern and its wiring pattern, as well as a terminal part for external connection and a reinforcing conductive foil on the back side of the terminal part. The present invention relates to a terminal reinforcement structure for a membrane keyboard switch configured to integrally form a membrane type keyboard switch.

``Prior Art'' This type of membrane type keyboard switch has a flexible insulating sheet member 1 made of a suitable plastic film with the required movable contacts on one side, as shown conceptually in FIG. 2. Contact pattern 2
A switch sheet is provided, and this switch sheet is bonded to a flexible circuit board having another contact pattern 5 provided as a fixed contact with an insulating spacer 3 interposed therebetween to form a switch operation gap. . This flexible circuit board includes the fixed contact patterns 5 formed on one side of the movable insulating base member 4 at a portion facing each of the movable contact patterns 2, and the contact patterns 5 corresponding to the movable contact patterns 5. The surface of a cover lay film or the like that protects the wiring pattern 6 for routing, the terminal portion 6A in the tail-shaped extension portion of this wiring pattern 6, and the other wiring patterns 6 other than the contact pattern 5 and the terminal portion 6A. A covering layer 7 is provided. In addition, the structure of the terminal part of such a membrane keyboard switch includes a polyester film or glass on the back side of the terminal part 6A for the purpose of ensuring insertion/removal processing with the connector for external connection and supplementing electrical and mechanical connection. It is common to provide a reinforcing sheet 8 for thickness adjustment such as an epoxy resin reinforcing film.

In membrane type keyboard switches, etc., which have a structure in which a large number of switches are arranged in a space where the number of switches is restricted, the wiring patterns 6 for routing the contact patterns 5 are also densely packed and complicated. It is also possible to form the wiring pattern 6 on the side opposite to the contact pattern 5 via a through-hole conduction means using a double-sided flexible circuit board manufacturing method. The installation position is reversed.

"The problem that the invention attempts to solve" In the membrane type keyboard switch as mentioned above,
In a terminal reinforcement structure in which a separate reinforcing sheet 8 for adjusting thickness is provided on the back side of the terminal 6A to be inserted and connected to a connector for external connection, it is necessary to bond the reinforcing sheet 8, and However, there is a problem in that there is a risk of positional deviation occurring during the bonding process.

Further, a contact pattern 5 is formed on one side of the flexible insulating base member, and a wiring pattern 6 for the contact pattern 5 and a terminal portion 6A at the end thereof are formed on the other side. If this is constructed using a double-sided flexible copper-clad laminate, all copper foil areas other than the contact pattern 5, wiring pattern 6, and terminal portion 6A are removed by etching means. Since this is necessary, if the step of attaching the separate reinforcing sheet 8 as described above is taken into account, this becomes a considerable factor in increasing costs.

``Means for Solving the Problems'' The present invention aims to improve the reinforcement structure of the terminal portion of this type of membrane keyboard switch by eliminating the problems of pasting misalignment and increased man-hours due to pasting of separate reinforcing sheets as in the past. By integrally forming a reinforcing conductive foil on the back side of the terminal part as well as forming the contact pattern, its wiring pattern, and the terminal part, a terminal with high adhesion and good mechanical strength can be created without any problems. This provides a reinforcing structure for the parts.

Therefore, in the terminal reinforcement structure of the membrane type keyboard switch according to the present invention, a switch sheet is provided with a desired contact pattern on one side of a flexible insulating sheet member, and the switch sheet is bonded to the switch sheet via an insulating spacer. and a flexible circuit board having another contact pattern arranged opposite to the contact pattern at a position corresponding to the contact pattern, the flexible circuit board having the contact point formed on one side of the insulating base member. A pattern, a wiring pattern for the contact pattern formed on the other side of the insulating base member via a through-hole conductive part, a terminal part at the end of the wiring pattern, and formation of the contact pattern on the back side of the terminal part. It is configured to include a reinforcing conductive foil disposed together with the reinforcing conductive foil. In such a structure, a surface coating layer such as a cover lay film is provided on the reinforcing conductive foil side except for the contact pattern part to adjust the insertion thickness into the connector and further increase the mechanical strength of the terminal part. It is also possible to do so.

"Embodiments" Hereinafter, the present invention will be described in further detail with reference to illustrated embodiments. In FIG. 1, reference numeral 11 denotes a flexible insulating sheet member, on one side of which a required number of contact patterns 12 as movable contacts are arranged to form a switch sheet. Reference numeral 13 indicates an insulating spacer in which a through hole for a switch operation gap is formed at a location corresponding to the arrangement of the contact pattern 12. on the other hand,
The other contact pattern 15 as a fixed contact, the wiring pattern 17 for its routing, the terminal portion 17A formed at the end, the reinforcing conductive foil 18, etc. are configured into a double-sided flexible circuit board structure as follows. A flexible insulating base member 14 made of a suitable plastic film is provided with a fixed contact pattern 15 disposed opposite each of the movable contact patterns 12 on one side thereof, and these contacts are A routing wiring pattern 17 necessary for the pattern 15 is formed as appropriate on the other surface of this insulating base member 14 via a through-hole conductive portion 16.
A terminal portion 17A for connecting to the connector of the wiring pattern 17 is arranged at the end of the tail portion extending and protruding from the area where the fixed contact pattern 15 is formed, and the back surface of the terminal portion 17A is provided with the terminal. The conductive foil 18 for reinforcing the contact pattern 15
At the same time as the formation of
These fixed contact patterns 15, wiring patterns 17 for routing thereof, terminal portions 17A, and reinforcing conductive foils 18 for the terminal portions are subjected to through-hole conduction processing to form through-hole conduction portions 16. It is easy to optimally construct the double-sided flexible copper-clad laminate by etching it.

Note that 19 and 20 are contact patterns 15, respectively.
The surface coating layer 19 formed on the reinforcing conductive foil 18 side is shown as a surface coating layer formed on the reinforcing conductive foil 18 side to protect the other conductor parts except for the formation area and the terminal part 17A. Together with the reinforcing conductive foil 18, this serves to ensure the strength of the terminal portion 17A, and to sufficiently increase the mechanical strength of the terminal portion 17A. Reference numeral 21 is an adhesive sheet for attachment to a counterpart device that can be provided on the side of the surface coating layer 20 of such a double-sided flexible circuit board, and when shipped, an appropriate release paper or the like is usually provided on the surface of the sheet. It is.

"Effects of the Invention" As described above, the terminal reinforcement structure of the membrane keyboard switch according to the invention has a structure in which a contact pattern is formed on the back surface of the terminal part for connection to a connector, and at the same time, a reinforcing conductive structure for the terminal part is formed. Since the structure is configured so that the foil is arranged, compared to the conventional structure in which a separate reinforcing sheet is attached, it is possible to reduce the number of attaching steps and to solve the problem of positional deviation during bonding. .

Such reinforcing conductive foil for the terminal portion can be provided in any desired shape at the same time as the etching of the contact pattern as the fixed contact, so that it can easily correspond to the shape of the terminal portion. and,
Such a reinforcing conductive foil may be constructed so that an extra conductive foil portion other than the contact pattern is left during the etching process, so that the etching process can be simplified.

In addition, the adhesion of the reinforcing conductive foil is good,
This is extremely advantageous as an integral reinforcing structure for the terminal portion.

In addition, when a surface coating layer such as a coverlay film is provided on the reinforcing conductive foil side, the mechanical strength can be further improved.

[Brief explanation of the drawing]

FIG. 1 is an enlarged cross-sectional configuration diagram conceptually showing the terminal reinforcement structure of a membrane keyboard switch according to an embodiment of the present invention, and FIG. FIG. 2 is a conceptual enlarged cross-sectional configuration diagram of a terminal portion of a membrane type keyboard switch. DESCRIPTION OF SYMBOLS 11... Insulating sheet member, 12... Contact pattern, 13... Insulating spacer, 14... Insulating base member, 15... Contact pattern, 16... Through-hole conduction part, 17... Wiring pattern, 17A...
...Terminal portion, 18...Reinforcing conductive foil, 19...Surface coating layer, 20...Surface coating layer, 21...Adhesive sheet.

Claims (1)

[Scope of utility model registration request] A switch sheet having a required contact pattern on one side of a flexible insulating sheet member, and another contact pattern bonded to the switch sheet via an insulating spacer and disposed opposite to the contact pattern at a position corresponding to the above contact pattern. The flexible circuit board includes the contact pattern formed on one side of the insulating base member and the contact pattern formed on the other side of the insulating base member via a through-hole conductive portion. It is characterized by being configured to include a wiring pattern for the formed contact pattern, a terminal portion at the end of the wiring pattern, and a reinforcing conductive foil disposed on the back side of the terminal portion at the same time as the formation of the contact pattern. Terminal reinforcement structure for membrane type keyboard switch.