JPH01189819A - Surface mounting type switch - Google Patents

Abstract

PURPOSE:To fix a switch on a printed board easily and with stability, by inserting a branched protrusion on the bottom of a casing into a hole of the printed board and press-introducing a pressing member projecting from the casing into the slit of the branched protrusion. CONSTITUTION:A protrusion 1d projecting from the bottom of the casing 1 of a switch and a branched protrusion 1a, are inserted into a positioning hole 5a on a printed board and an inserting hole 5b of a branched protrusion 1a, respectively, and a pressing member 1c projecting from a art of the casing 1 is press-introduced into the slit 1b of the branched protrusion 1a, The switch is thereby firmly mounted on the printed board 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a switch, and more particularly to a surface-mounted switch of the type that is surface-mounted on a printed circuit board.

[Conventional technology]

Conventionally, when mounting this type of surface mount switch on a printed board, before soldering to the terminals, screws were inserted into mounting holes made in the casing as well as holes in the printed board in order to attach the switch itself to the printed board. Those that attach to nuts were widely known.

[Problem that the invention seeks to solve]

The surface mount type switch described in the conventional technology uses mounting screws, so it is necessary to use a mounting tool such as a dowel, and many screws, nuts, and other mounting parts are required, making the mounting work time-consuming. There was a problem in that it was difficult to install.

In addition, when performing surface mounting, high temperatures are applied to the entire switch during glue flow soldering, but at that time, the rate of thermal deformation between the metal mounting screw and the switch mounting hole, which is generally made of a synthetic resin molded product, is different, so the mounting hole and the mounting hole are different. There was a problem in that play was generated between the switch and the screw, making it difficult to perform stable surface mounting of the switch.

The present invention has been made to address the above-mentioned problems and aims to provide a surface-mounted switch that can be easily and stably surface-mounted on a printed circuit board.

[Means for solving problems]

The present invention provides a switch that can be easily surface mounted by inserting a bifurcated protrusion on the bottom of a casing into a hole in a printed board and press-fitting a press-fitting member protruding from a part of the casing into the slit of the bifurcated protrusion. It is something.

An embodiment of the present invention will be described below based on the drawings.

In Figure 1 +a) to tel, l is box-shaped PET
The casing is made of highly heat-resistant and flexible synthetic resin such as (polyethylene terephthalate resin) or PP5 (polyphenylene sulfide resin), and the switch body 2 is inside.
is stored. The switch body 2 is a push button 4.4
This is a 2A contact type that is opened and closed by the following. 3,3
．． A terminal 3 is electrically and mechanically connected to the switch body 2 and protrudes from the casing 1 in a direction substantially parallel to the bottom surface of the casing 1 on the printed board mounting surface. A positioning projection xd is formed on one side of the bottom surface of the casing l, and a cylindrical bifurcated projection 1a having a slit portion xb is provided on the other side. Further, on the bifurcated protrusion la, a flat press-fitting member IC that is press-fitted into the slit portion 1b projects from a part of the casing l.

The switch is mounted with high precision by inserting the positioning protrusion 1d and the bifurcated protrusion 1a into the positioning hole 5a provided in the printed board 5 and the insertion hole 5b of the bifurcated protrusion 1a, respectively. By press-fitting the press-fitting member IC into the slit portion lb of the protrusion 1a, the switch whose bifurcated protrusion 1a is press-fitted into the hole 5b can be surface-mounted onto the printed board 5 with one touch. Incidentally, on the outer periphery of the press-fitting member IC, an uneven part is formed to engage with an uneven part provided on the inner surface of the slit part xb. The outer peripheral surface of the protrusion 1H is also provided with an uneven portion so that it can be firmly attached to the hole 5b of the shiblint plate 5. Therefore, the switch is firmly mounted on the printed board 5.

After the switch is mounted firmly and accurately on the printed board 5, the circuit pattern (not shown) on the printed board 5 and each terminal 3 are soldered together by reflow soldering, and the switch body l is electrically connected to the circuit. It is connected to

During reflow soldering, a high temperature similar to the solder melting temperature is also applied to the casing l, and the bifurcated protrusion la into which the press-fitting member IC is press-fit is thermally deformed, but since the press-fitting member IC is made of the same material as the bifurcated protrusion 1a, the heat deforms the bifurcated protrusion la. The degree of deformation is also the same, so even if there is a temperature change, the bifurcated protrusion 1a is stably press-fitted into the hole 5b of the printed board 5, and the switch is always firmly attached to the printed board 5 without any play in the switch fixing part. It's something you can wear.

The press-fitting member IC may be constructed as a separate member from the casing 1 as shown in FIG. 2, as long as it is made of the same material as the casing 1 and can be stably press-fitted into the bifurcated protrusion 1a.

〔Effect of the invention〕

As described above, the present invention forms a bifurcated protrusion having a slit on the bottom surface of a casing, inserts the protrusion into a hole in a printed board, and inserts a press-fit member protruding from a part of the casing into the slit of the bifurcated protrusion. Press-fitting eliminates the need for conventional separate mounting parts such as screws and nuts, reducing the number of parts, and allows the switch to be surface-mounted on a printed board with a single touch by press-fitting the press-fitting member.

In addition, Karari flow soldering, in which the press-fitting material is made of the same material as the casing, allows the switch to be stably attached to the printed board without any looseness, unlike in the case of conventional screws, even if the switch is sometimes deformed by heat. be.

[Brief explanation of the drawing]

Figure 1 +a), +111. 6J) is a plan view, FIG. 1BL is a front view, and +C) is a side view. Figures 2 +a+, +bl, +c) respectively show other embodiments of the present invention, in which Figure 1al is a plan view, Figure +b+ is a front view, and Figure 1c) is a side view. l...Casing, 1a...Bifurcated protrusion, lb...
Slit part, IC...press-fitting member, 2...switch body, 3...terminal, 5...printed board, 5b...hole.

Claims (1)

[Claims] 1) In a surface mount switch that has a casing made of a flexible material that houses a switch body and a terminal protruding from the casing that is attached to the surface of a printed board, a bifurcated protrusion having a slit is formed on the bottom surface of the casing. ,
A surface-mounted switch characterized in that the bifurcated protrusion is inserted into a hole in a printed board, and a press-fitting member protruding from a part of the casing is press-fitted into the slit portion of the bifurcated protrusion.