KR100549917B1 - Switching apparatus for key pad in mobile communication phone - Google Patents

Abstract

The present invention employs a switching element of a keypad as a thin metal dome sheet, but forms the structure of the metal dome sheet into a structure having protrusions in a rectangular section, thereby enabling high-speed automatic insertion into a switching pattern of the substrate and thus providing the substrate to the substrate. The present invention relates to a switching device for a keypad of a mobile communication terminal that can maximize work efficiency and reduce costs by minimizing work time and labor required to attach a switching device.

The present invention provides a printed circuit board having a plurality of switching patterns formed on the upper surface thereof in a concentric shape, wherein a plurality of switching patterns are formed in which circles of the remaining portions except the center circle are divided at a predetermined angle; And it provides a switching device for a keypad of a mobile communication terminal having a dome sheet mounted on the switching pattern and a switching function so as to correspond to the switching pattern of the printed circuit board, and mounted on the switching pattern.

Mobile communication terminal, keypad, dome sheet, concentric pattern, protrusion, steam outlet

Description

Switching apparatus for key pad of mobile communication terminal             

1 is a cross-sectional view showing a keypad structure of a general mobile communication terminal.

Figure 2a Figure 2b is a substrate pattern for keypad switching of the mobile communication terminal according to the prior art.

Figure 3 is a perspective view showing the structure of a switching module mounted on the substrate pattern of Figure 2b.

4A and 4B are substrate pattern diagrams for keypad switching of a mobile communication terminal according to the present invention;

Fig. 5 is a schematic diagram showing the structure of a dome sheet mounted on the substrate pattern of Fig. 4B.

* Explanation of symbols for main parts of the drawings

1: printed circuit board 2: switching pattern

3: end pattern 4: dome sheet

5: protrusion 6: steam outlet

The present invention relates to a switching device for a keypad of a mobile communication terminal, and more particularly to a switching device for a keypad of a mobile communication terminal that can improve the efficiency of the metal dome mounting operation to perform the switching function of the keypad and reduce the cost. .

In general, a mobile communication terminal performs a communication function while performing wireless communication with a base station or an external fixed device, and refers to a mobile device such as a mobile phone, a wireless telephone, or a car phone.

A keypad used in a communication device such as a portable terminal and the like as a switching device for generating a signal includes: a key top 101 having a printing surface 101a such as numbers or letters formed thereon as shown in FIG. 1; It has a base 102 for supporting the key top 101, the key top 101 is fitted into a hole provided in the front housing 103 of the communication device, a part of which is assembled in a structure protruding outside the front housing .

In addition, a printed circuit board 104 is installed at the bottom of the base 102, and an LED light source is installed on the printed circuit board 104 so that the printed surface 101a of the key top 101 can be checked at night. Therefore, as the light is irradiated from the LED light source, the user can recognize the number or letter printed on the key by the backlighting effect.

Mounting of the switching element in the keypad structure as described above is made by soldering the switch unit to the substrate to fix it, or metal dome to the substrate fixed to the substrate, these mounting methods commonly require a thin thickness It should be light.

In a conventional keypad implementation method, as shown in FIGS. 2A and 2B, the switch pattern 202 formed on the substrate 201 is formed in a concentric shape, and the switch pattern 202 is illustrated in FIG. 3. The switching module 203 or a dome-shaped metal sheet adhered to the vinyl sheet is mounted.

These switching modules 203 and the dome sheet are soldered to two nodes on the substrate or connected by mechanical contact to switch by external forces.

However, there are various problems when mounting the switch module 203 or the dome sheet on the switching pattern of the substrate.

First, when the switch module 203 is mounted on the switching pattern 202 of the board, the unit module itself is very expensive, and the thickness of the switch module becomes thick due to the mechanical structure of the switch module (usually 1 to 2 mm). The thickness of the cell is naturally thick, but the thickness of the cell phone is becoming smaller and smaller.

In addition, when the dome sheet is mounted on the switching pattern 202, it is the most widely used method up to now, but since the process of attaching the sheet to the substrate must depend entirely on manual labor, labor and labor costs are high. There is a disadvantage that takes a lot of time in manufacturing. In addition, there is a problem that the manufacturing cost including the process of attaching the round thin film dome in the plastic sheet from the manufacturer, resulting in a high unit cost.

On the other hand, the concentric switching pattern has excessive lead in the surface mounting technology (SMT), which leads to the problem that the lead rises on the thin film dome sheet to interfere with the normal switching operation.

Therefore, the present invention has been proposed to solve the above problems, by employing the switching element of the keypad as a thin metal dome sheet, by forming the structure of the metal dome sheet with a protrusion having a rectangular portion In order to provide high-speed automatic insertion into the switching pattern of the board, it minimizes the work time and labor required to attach the switching element to the board, thereby maximizing the work efficiency and providing a switching device for the keypad of the mobile communication terminal that can reduce the cost. The purpose is.

The present invention for achieving the above object is a printed circuit board formed on the upper surface of the concentric circles, the plurality of switching patterns formed by dividing the circle of the remaining portion other than the center circle at a predetermined angle; And it provides a switching device for a keypad of a mobile communication terminal having a dome sheet mounted on the switching pattern and a switching function so as to correspond to the switching pattern of the printed circuit board, and mounted on the switching pattern.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 4A to 5.

Switching device for keypad of the mobile communication terminal according to the present invention can be achieved to fasten the work to be fixed to the switching pattern of the substrate, to reduce the product cost, in the embodiment of the present invention Figures 4a and 4b As shown in FIG. 2, a plurality of switching patterns 2 are formed on the printed circuit board 1 of the mobile communication terminal, and the switching patterns 2 are formed in concentric circles. It is a structure formed by the end pattern 3 divided by predetermined angle.

In addition, the switching pattern 2 having the end pattern 3 has a thin film dome in which a protrusion 5 is formed on a corresponding portion of the end pattern 3 divided to correspond to the pattern shape thereof, as shown in FIG. 5. Seat 4 is mounted to perform a switching function

Here, the dome sheet is made of a material that is not adsorbed with lead.

By the structure of the dome sheet 4 formed as described above, a steam outlet 6 is formed between the protrusions 5 to function as a passage for discharging the flux steam which may occur in the surface mount oven.

In addition, in the embodiment of the present invention by coating a nickel plating layer on the bottom of the protrusion 5 of the dome sheet 4, when mounting on the switching pattern (2), the lead only to the nickel plating layer to achieve a smooth soldering by excessive soldering Prevents faulty switching operations.

The dome sheet configured as described above has a protrusion and a vapor discharge port, so that the surface mounting device can smoothly grip the dome sheet, thereby automatically inserting the dome sheet into the switching pattern.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and will be apparent to those skilled in the art without departing from the technical spirit of the present invention.

As described above, according to the present invention, by forming a vapor discharge port between the protrusion formed by dividing the structure of the dome sheet at a predetermined angle and the protrusion, it is possible to facilitate the operation of the surface-mounting equipment to hold, thereby switching patterns Since the dome sheet can be automatically inserted at high speed, the fixing work time can be greatly reduced, and the labor required for the fixing work can be reduced.

In addition, since the dome sheet has a divided protrusion, the cost of the product can be reduced, and a nickel plating layer that can be bonded with lead is applied only to the lower end of the protrusion to function as a switch that can control electrical signals with mechanical stability. It has other effects that can be reliably achieved.

Claims (4)

A printed circuit board formed in a concentric shape on an upper surface thereof, and having a plurality of switching patterns in which circles of other portions except for a center circle are divided at predetermined angles; And A dome sheet having a protrusion corresponding to the divided part thereof so as to correspond to the switching pattern of the printed circuit board, and mounted on the switching pattern to perform a switching function. Switching device for the keypad of the mobile communication terminal comprising a. The method of claim 1, It further comprises a nickel plated layer coated on the bottom of the protrusion of the dome sheet for smooth soldering when mounting on the switching pattern Switching device for keypad of mobile communication terminal. The method according to claim 1 or 2, Further comprising a steam outlet formed between the projections of the dome sheet corresponding to the divided portion of the switching pattern Switching device for keypad of mobile communication terminal. The method according to claim 1 or 2, The dome sheet is made of a thin film form, characterized in that made of a material that is not adsorbed lead Switching device for keypad of mobile communication terminal.

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