JPS6161312A - Contact pattern structure of pushbutton switch - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a contact pattern r in a push button switch.
・Regarding 1st construction.

In push button switches that have a conductive part at the bottom of the middle top and form contact parts in a pattern on the opposing printed wiring board, the contact pattern formed on the conventional printed wiring board is usually simple. The structure consisted of alternating combinations of comb-shaped patterns. In this case, when pressing down on the center of the key top, the contacts are securely made, but when pressing the corner or edge of the top, only one side of the contact pattern is provided at the bottom of the key top. Switching may not occur properly because the conductive parts do not make contact.

The purpose of the present invention is to make the contact pattern fan-shaped and arrange a plurality of contacts in a circular pattern at regular intervals, so that when pressing the corner or edge of the key top, the pressing blade is the same as when pressing the center of the key top. The purpose of the present invention is to provide a contact pattern structure for a pushbutton switch that operates in accordance with the present invention.

According to the present invention, there is provided a pushbutton including a vertically movable key top portion having a conductive portion at the bottom thereof, and a contact pattern formed on a printed wiring board disposed below the key top portion and facing the conductive portion. In the button switch, the contact pattern includes a plurality of fan-shaped conductive parts arranged radially at regular intervals from one point, and the fan-shaped conductive parts are coupled every other in the arrangement direction to form two contacts. A contact pattern structure of a pushbutton switch is obtained.

Next, embodiments of the present invention will be described with reference to the drawings.

Referring to FIG. 1 and FIG.
A cylindrical conductive rubber 4 integrally molded with the key top part 3 is fixed to the center of the key top part 3, and a contact pattern [' is formed on the printed wiring board 5 opposite to the cylindrical conductive rubber 4. The key top 3 is fixed to a bottom plate 3b via an elastic portion 3a' so that a certain distance 4' is left between the conductive rubber 4 and the printed wiring board 5, and the bottom plate is fixed to the printed wiring board 5. By pressing the key top 3 a certain amount, the conductive rubber 4 comes into contact with the contact pattern 1' and is electrically made.

The contact pattern of the printed wiring board 5 is eight fan-shaped conductive parts L.
It consists of a sector pattern of a, Lb, LC, ld, 2a12b12C, and 2d, and the center of the sector is the same as the center of the key top portion 3. Each sector-shaped conductive part is arranged radially at regular intervals at an angle of 45 degrees with respect to each other, so as not to come into contact with an adjacent sector-shaped conductive part.

This switch has a conductive path 2a/,
The contact pattern consists of two contacts. In other words, one contact point is a fan-shaped conductive part 1a and a counterclockwise rotation of 90° with the fan-shaped conductive part 1a as a reference.
, 180°, 270° positions
b, Ic, and Id are patterned/connected at the center, forming a cross shape, and connected to the conductive portion Lb/. The other contact point is the fan-shaped conductive part 2a, and the counterclockwise rotation of 90°, 180°, with this fan-shaped 4-conductor part as a reference.
Sector-shaped conductive parts 2b, 2c, 2 arranged at 270° positions
a are pattern-connected to each other via a conductive path 2' at a part of the fan-shaped outer periphery, and are connected to a conductive portion 2a/. The outer diameter of each fan-shaped conductive part of the two contacts is the same,
2F provided at the bottom 3' of the key top 3! -The diameter of electric rubber 4 is larger. Also, the fan-shaped conductive part 2 a * 2 b
The inner diameter of +2'+2d is smaller than the diameter of the conductive rubber 4.

FIGS. 3, 4, and 5 are plan views showing the state of contact between the conductive rubber and the contact when the key top is pressed.

In FIG. 3, when the center of the key top 3 is pressed fc, the large dotted portion 10 shows the contact surface of the conductive rubber 4. When the center of this xvc key is pressed down, it contacts all the sector-shaped conductive parts.

FIG. 4 shows the contact state when the key top 3 is pressed at a corner. The combination of sector-shaped conductive parts that is easiest to connect when pressing squarely is
4 of la and 2a, lb and 2b, Lc and 2c, Id and 2d
There is one.

FIG. 5 shows the welded state when the key top 3 is pressed at the end. The combination of sector-shaped conductive parts that is easiest to connect when pushing the end is:
2a and Lb, 2b and 1c, 2c and Ia, 2d and 1a 4
There is one.

In the above embodiment, eight fan-shaped conductive parts were concentrically arranged at 45° intervals, but within the range of contact pattern manufacturing capacity, the arrangement angle of the fan-shaped conductive parts was n(n-1°2, 45°). ), and the number of patterns is preferably (8xn). This is because as n increases, the switching sensitivity to pressing the key top increases.

As explained above, by arranging the contact pattern including a plurality of fan-shaped 25@ parts, the present invention has the effect of ensuring the same switching as when pressing the center part even when pressing the corner or edge of the key top. There is.

[Brief explanation of drawings]

Fig. 1 is a plan perspective view showing an embodiment of the present invention, Fig. 2 is a partial sectional view showing an embodiment of the invention, and Fig. 3 is contact with the contact pattern when the center of the key top is pressed down. Fig. 4 is a plan view showing the state of contact between the key top and the contact pattern when the key top is pressed once, and Fig. 5 is a plan view showing the state of contact with the contact pattern when the key top is pressed the rest of the way. FIG. 1/ ・・・・・Contact pattern, L ” + l b
+l c+l d*2a, 2b, 2C, 2b...
...Fan shaped conductive part, 3...Key top part, 4...
...Conductive rubber, 5. Old... Printed wiring board. Agent: Susumu Uchihara, Patent Attorney

Claims (1)

[Claims] A push button switch comprising: a key top portion having a conductive portion at a lower portion thereof; and a contact pattern formed on a printed wiring board disposed below the key top portion and contacting the conductive portion when the key top portion is pressed. , the contact pattern is composed of a plurality of fan-shaped conductive parts arranged radially from one point at regular intervals, and the fan-shaped conductive parts are coupled every other in the arrangement direction to form two contacts. Features a contact pattern structure for pushbutton switches.