JPH0525140Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Technical field of invention] This idea relates to a switch structure.

[Prior art and its problems]

Conventionally, small electronic devices that can be stored in pockets etc.
For example, a thin calculator has a seat switch on the top surface.

The structure of this seat switch is such that an insulating spacer is sandwiched between a base film with contact printing (movable contacts) formed on the bottom surface and a circuit board with contacts (fixed contacts) formed on the top surface. By pressing , the movable contact and the fixed contact can be brought into contact with and separated from each other for switching.

However, the reset key, which is a switch that plays the role of all-clearing the memory, etc., is attached as a separate structure on the side opposite to the seat switch, because with the above-mentioned switch structure, there is a risk that the input data memory will be erased due to erroneous operation or malfunction. Therefore, the cost was high.

[Purpose of invention]

This invention was made in view of the above-mentioned circumstances, and its purpose is to provide a switch structure that does not erase memory due to erroneous operation or malfunction.

[Key points of the idea]

In order to achieve the above-mentioned object, the gist of this invention is to form a concave surface smaller than the pressing surface on the movable contact of a base film having the movable contact on the lower surface.

〔Example〕

Hereinafter, this invention will be specifically explained based on FIGS. 1 to 3.

This embodiment shows an example in which the present invention is applied to a calculator.

This calculator is a portable thin calculator that can be stored in a pocket or the like, and has a display section 2 and a switch section 3 on the top surface of a case 1.

In this case, the switch part 3 has number keys placed on the top surface,
It consists of a base film 4 on which a reset key etc. are printed, a circuit board 5 provided under the base film 4, and an insulating spacer 6 sandwiched between the base film 4 and the circuit board 5. Contact printing 7 is formed on the bottom surface of the base film 4 corresponding to the number keys, and contact printing 8 is formed on the bottom surface of the base film 4 corresponding to the reset key.
is formed, and each contact (movable contact)
Contact printing (fixed contacts) 9 are formed on the upper surface of the circuit board 5 corresponding to 7 and 8.
The contacts 7, 8, and 9 are separated by a cavity 10 formed in the insulating spacer 6.

As shown in FIG. 2, the number keys can be used to press the base film 4 with a finger to bring the contacts 7 into contact with and separate from the contacts 9. However, the reset key is constructed such that it is not possible to press the base film 4 with a finger to bring the contact 8 into contact with or separate from the contact 9.

As shown in FIG. 3, the configuration of this reset key is such that a concave surface 12 is formed by embossing the pressing surface 11 of the base film 4, and a movable contact 8 is formed on the tip of the concave surface 12. , an insulating protrusion 13 is integrally formed on the tip end surface of the concave surface 12 of the base film 4 surrounding the movable contact 8. This protrusion 13 is arranged between the lower surface of the recessed surface 12 and the upper surface of the circuit board 5 and is in contact with the upper surface of the circuit board 5.

Further, the above-mentioned concave portion surface 12 is formed smaller than the pressing surface that is pressed with a finger. The pressing force applied with a finger is regulated by the spacer 6 and the protrusion 13, and the movable contact 8 does not come into contact with or separate from the fixed contact 9.

When turning on the reset key, it is sufficient to use a pen tip or the like instead of a finger to press only the concave surface 12 to bring the movable contact 8 into contact with and away from the fixed contact 9.

In this way, this reset key
Pressing just the reset key will turn it on, but pressing the entire reset key will not turn it on, which prevents the switch from being operated by mistake and prevents the memory from being erased.

In the above-mentioned embodiment, an example was shown in which the switch structure was applied to a calculator, but the switch structure can be applied to small electronic devices other than calculators.

[Effect of idea]

As explained in detail above, this invention has a concave surface smaller than the finger pressing surface formed on the movable contact of the base film with the movable contact provided on the lower surface, so that the switch will not be operated by mistake. This has the advantage of preventing memory erasure.

[Brief explanation of drawings]

The drawings show one embodiment of this invention, and FIG. 1 is a perspective view of a calculator, FIG. 2 is a sectional view of a main part of a number key, and FIG. 3 is a sectional view of a main part of a reset key. 4...Base film, 5...Circuit board, 7,
8... Movable contact, 9... Fixed contact, 12... Concave surface.

Claims (1)

[Scope of utility model registration request] In a switch structure in which a base film with a movable contact on the bottom surface is pressed on the movable contact and the movable contact is brought into contact with and separated from a fixed contact provided on the top surface of the circuit board, a recess smaller than the surface of the base film that is pressed by a finger. , the movable contact is provided at the center of the tip of the recess, and a protrusion is further provided around the movable contact for abutting against the circuit board and forming a clearance between the movable contact and the circuit board. Switch structure.