JPS5914987Y2 - thin film switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in thin film switches used in typewriter keyboards and the like.

Conventionally, a common ground (earth) electrode formed on a fixed plastic film on the base and multiple contact electrodes formed by printing patterns and etching on the operating plastic film are placed opposite to each other via an insulating spacer. Thin-film switches made with this technology are used in typewriter keyboards, etc.

The common ground electrode is wide enough to completely cover the operating section.

Further, a round hole is provided in a portion of the spacer facing each contact electrode, and the contact electrode is located in the center of this round hole.

If you now press the operation button corresponding to the specified contact electrode,
The operating plastic film near the electrode is elastically deformed within the round hole of the spacer, and the contact electrode is electrically connected to the common ground electrode to select a desired channel.

In other words, the switch is activated.

These conventional thin-film switches are thin, do not take up much space, and have a sealed structure that makes them dust-proof, oil-proof, and waterproof.Also, each contact electrode has a printed pattern,
It has various advantages such as being formed at low cost and with high precision by etching, and enabling high-density mounting.

However, in this case, since the recovery of the switch is performed by the restoring force of the operating plastic film,
The number of operations was limited to several times for 7 seconds, and high-speed response could not be obtained.

The present invention is intended to solve the above-mentioned problems, and aims to provide a thin film switch with high-speed response.

Embodiments of the invention will now be described with reference to the drawings.

FIG. 1 is a plan view showing the non-operating state of the thin film switch according to the present invention, FIG. 2 is an exploded perspective view of the same, and FIG. 3 is a cross-sectional view of the same.
FIG. 4 is a longitudinal sectional view of the same, and in the figure, 1 is a base and 2 is a damper material.

A fixed plastic film 3 is fixed on the base 1, and a common ground electrode 4 is provided on the surface of the fixed plastic film 3, the width of which completely covers the operating section.

The damper material 2 is made of a flexible and elastic material,
A plastic film for operation is attached to the bottom surface.

A plurality of elongated contact electrodes 6 are provided at equal pitches on the surface of the operating plastic film 5, and these contact electrodes 6 are separated from the common ground electrode 4 by a predetermined distance via an insulating spacer 7. They are facing each other through.

The contact electrode 6 is made of a thin copper plate 6, as shown in detail in FIG.
It is formed by applying Ni plating 5b and Au plating C to the surface of a.

Ni Metsukiro B serves as a base for Au plating and has appropriate elasticity, and Au Metsukiro C improves the durability of the electrode.

The spacer 7 has a plurality of circular holes 8 for the contact electrodes 6.
The contact electrodes 6 are provided at equal pitches, and each contact electrode 6 straddles the hole 8 in a bridge shape as shown in FIG.

The structure of the thin film switch according to the present invention is as described above, and its operation will be explained next.

Now, as shown in FIGS. 6 and 7, predetermined contact electrodes 6,
When the operation buttons 9A and 9B corresponding to 6 are pressed, the contact electrodes 6, 6, the damper material 2 near the electrodes, and the operating plastic film 5 are elastically deformed in the hole 8, and the contact electrodes 6, 6 are pressed. It is electrically connected to the common ground electrode 4 to enter a switch operation state, and a desired channel is selected.

When the pressure on the operation buttons 9A and 9B is released, the damper material 2, the operating plastic film 5, and the contact electrodes 6, 6 return to their original positions due to their respective restoring forces.

In this way, switch revenge 18! In addition to the restoring force of the damper material and the operating plastic film, the restoring force of the contact electrodes is also added, and the restoring force of the contact electrodes is large because the restoring force of the Ni plating is also added to the restoring force of the thin copper plate 6a. As a result, the time required for reversing is much shorter than in the past, and high-speed response is achieved.

As described above, according to the present invention, in addition to the restoring force of the damper material and operating plastic film, the restoring force of the contact electrode is also added, and the restoring force of the contact electrode is Since the restoring force of the thin copper plate is increased by adding the restoring force of the Ni plating applied to the surface thereof, the recovery time can be significantly shortened and high-speed response can be obtained.

Note that the damper material may be omitted by using a plastic film for operation with appropriate elasticity.

[Brief explanation of the drawing]

The figure shows an example of a thin film switch according to the present invention.
Figure 1 is a partially cutaway view, Figure 2 is an exploded perspective view (base and damper material omitted), Figure 3 is a cross-sectional view, Figure 4 is a longitudinal cross-sectional view, and Figure 5 is a contact electrode. 6 and 7 are a cross-sectional view and a vertical cross-sectional view showing the switch operating state. In the figure, 1 is the base, 2 is the damper material, 3 is the fixed plastic film, 4 is the common ground (earth) electrode, 5
is a plastic film for operation, 6 is an electrode for contact, 6a
is a copper thin plate, 6b is Ni plating, 6C is Au plating, 7 is a spacer, 8 is a hole, 9A. 9B is an operation button.

Claims (1)

[Scope of utility model registration request] On the grounding electrode formed on the surface of the fixed plastic,
In a thin film switch, a plurality of contact electrodes formed on the surface of an operating plastic film are made to face each other via an insulating spacer having a plurality of holes corresponding to each of the contact electrodes. A thin film switch characterized in that the electrode is formed by applying Ni plating and Au plating to the surface of an elongated thin copper plate that spans the hole in a bridge shape.