KR101064328B1 - Slim keypad for communication terminal and the fabrication method thereof - Google Patents

Abstract

The present invention relates to a slim keypad for a mobile communication terminal and a method of manufacturing the same, and more particularly, to a keypad for a mobile communication terminal for pressing a dome switch to contact a contact, wherein a plurality of penetrations are provided at positions corresponding to the dome switch. A frame provided with a ball; A sheet disposed to cover the through hole and attached to an upper side of the frame; And a key button disposed at a position corresponding to the through hole and attached to an upper side of the sheet, and having a letter or a number formed on an upper surface thereof, and having a protrusion protruding from the lower surface of the sheet to press the dome switch. In the case of pressing a button, the seat extends, and the key button presses the dome switch to a slim keypad for a mobile communication terminal and a method of manufacturing the same.

Frame, seat, key button, protrusion, slim

Description

Slim keypad for mobile communication terminal and manufacturing method thereof

The present invention relates to a slim keypad for a mobile communication terminal and a method of manufacturing the same, and more particularly, to a slim keypad for a mobile communication terminal and a method for manufacturing the same, by forming protrusions on a key button integrally and thinning the overall keypad. It is about.

The mobile communication terminal refers to a communication terminal such as a mobile phone or various PDAs that can randomly move in a mobile communication service area and talk to a general subscriber or another mobile communication phone through a base station.

Such mobile communication terminals have been gradually increasing in size and thickness as various functions are built in. As the functions are diversified, as the size of the mobile communication terminal increases, the population complaining of the inconvenience of carrying is increasing.

On the other hand, the structure of a mobile communication terminal according to the prior art is as follows.

First, a plurality of contacts are disposed on an upper surface of a printed circuit board, and a plurality of dome switches are disposed to cover the contacts. As the contact point and the dome switch come into contact with each other, a predetermined electrical signal is applied, thereby performing a function desired by a user.

On the other hand, in order to couple the dome switch to the contact point, the dome switch is pressed so that the bottom surface of the dome switch contacts the contact point. Thus, a keypad is used as a means for contacting the dome switch with the contact point.

As shown in FIG. 1, the keypad includes a frame made of a metal material having a predetermined through hole, a sheet disposed below the frame and covering the through hole, and attached to a lower surface of the sheet. And a key base provided with a projection, and a key button disposed above the sheet and provided in the through hole.

The keypad according to the prior art operates as follows.

First, when a user presses a key button with his or her finger, the key base and the seat disposed below the key button are simultaneously pressed and move downward, and accordingly, the projection is lowered to press and press the center upper surface of the dome switch. The dome switch comes into contact with the contact. As such, when the dome switch contacts the contact, a predetermined electrical signal is generated and a predetermined operation desired by the user can be performed.

The keypad according to the prior art has the following problems.

First, the keypad according to the prior art is formed with a key base formed with protrusions on the lower surface of the sheet. Such a key base is typically made of a soft material such as silicon so that compression and extension can be facilitated by the pressing force of the key button. However, in order to reduce the strength that may occur by using a material that is easily deformed as described above, it is manufactured to have a thickness of at least 0.2 mm or more, which has been hindering the slimming of the entire keypad.

Second, the protrusions are made of a soft material like the key base, and should have a thickness of at least 0.25 mm to have sufficient strength. That is, the total thickness of the key base including the projection must be at least 0.45 mm or more to produce a key base without defects, which is a limitation in the implementation of the ultra-compact mobile communication terminal.

Third, the keypad according to the prior art, as described above, the key base and the projection should be thick enough to maintain the strength, it is not easy for the user to press the key button. That is, since the load for the click must be large, the user is not only tired, but also has a problem that the click feeling is not good in the process of repeatedly pressing the key button.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to provide a slim keypad for a mobile communication terminal and a method for manufacturing the same, which can improve a feeling of click while reducing the overall thickness of the keypad.

Hereinafter, a slim keypad for a mobile communication terminal according to a preferred embodiment of the present invention is a keypad for a mobile communication terminal for contacting a contact by pressing a dome switch, wherein a plurality of through holes are provided at a position corresponding to the dome switch. ;

A sheet disposed to cover the through hole and attached to a lower side of the frame; And

It is disposed in a position corresponding to the through hole and attached to the upper side of the sheet,

It includes a key button that is pushed by the user to be moved downwards, protruding projections for pressing the dome switch on the bottom surface;

Preferably, a portion of the sheet corresponding to the protrusion of the key button is attached to surround the surface of the protrusion.

In the slim keypad for the mobile communication terminal, the key button is preferably made of a high hardness synthetic resin material of higher hardness than silicone or rubber.

In the slim keypad for the mobile communication terminal, the synthetic resin material, preferably comprises any one of PC, ABS, PC / ABS or PMMA.

In the slim keypad for the mobile communication terminal, the protrusion preferably has a curved shape with a smooth edge.

In the method of manufacturing a slim keypad for a mobile communication terminal according to the present invention for achieving the above object, a key button manufacturing step of providing a key button is formed on the bottom of which a projection for pressing the dome switch integrally formed ;

A frame attaching step of attaching a sheet to the frame provided with a plurality of through holes to cover the through holes;

Key button attachment step for attaching each key button for each position corresponding to the through hole on the upper side of the sheet;

In the manufacturing method, the key button attaching step,

An application step of applying a UV curable paste to an upper surface of the sheet or a lower surface of a key button;

An adhesion step of bringing the upper surface of the sheet and the lower surface of the key button into close contact with each other; And

And a curing step of bringing the sheet and the key button into contact with each other as the UV-curable paste is cured by irradiating ultraviolet rays.

In the above production method,

The adhesion step,

An attachment mold preparation step of preparing an attachment mold having an upper surface thereof having a flat surface corresponding to the lower surface of the sheet but having an insertion groove having a shape corresponding to the protrusion only at a position corresponding to the protrusion of the key button;

Stacking the sheet and the key button with the frame attached to the attachment mold in sequence, wherein the key button has a position alignment step of placing the protrusion at a position corresponding to the insertion groove;

It is preferable to include; entering the step of pressing the key button to the lower side so that the projection of the key button enters into the insertion groove with the seat.

In the above production method,

Preferably, the sheet and the attachment mold are made of a transparent material through which ultraviolet light can pass.

In the above production method,

The curing step,

And placing the ultraviolet irradiation means on the opposite side of the key button with the adhesion mold therebetween, irradiating the ultraviolet rays from the ultraviolet irradiation means so that the ultraviolet rays pass through the adhesion mold and the sheet to reach the UV curable paste. It is desirable to.

The slim keypad for a mobile communication terminal according to the present invention has an advantage in that the thickness can be reduced as a whole because the key base is removed and a protrusion is integrally formed with the key button.

In addition, since the protrusion is made of the same high hardness material as the key button, there is an advantage that the dome switch can be sufficiently pressed even if the thickness of the protrusion is reduced as compared with the conventional technology.

In addition, there is an advantage that the material cost and the like can be reduced as the key base is removed.

In addition, since the key button is supported only by the sheet, the overall click load can be reduced, thereby improving the click feeling.

In addition, the slim keypad for a mobile communication terminal according to the present invention has a merit that the key button including the projection is made of a high hardness material as a whole, so that the dome switch can be sufficiently pressed even if the thickness is thin, thereby reducing the overall thickness. .

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

 The slim keypad 10 according to the present embodiment is for contacting the contact 52 by pressing the dome switch 51. In this case, a plurality of the dome switches 51 are arranged in the horizontal direction, and the contact 52 for generating a predetermined electrical signal when the dome switch 51 is in contact with the dome switch 51 at the center lower side of the dome switch 51. It is provided on this printed circuit board 50.

The slim keypad 10 includes a key button 20, a frame 30, and a seat 40.

The key button 20 is preferably a letter or number is formed on the upper surface and the projection 22 for pressing the dome switch 51 is preferably formed on the lower surface.

Specifically, the key button 20 is composed of a body portion 21 and the projection (22). The body portion 21 is a portion in which the letter or number is formed on the upper surface of the user's finger can be contacted. The letters or numbers may be directly printed on the surface of the body portion 21, but a printed film or the like may be attached.

The body portion 21 may have a somewhat curved shape whose thickness at the center thereof is thicker than the thickness of the adjacent portion, or may have a flat shape as a whole.

When the body portion 21 is formed in a curved shape, the center thickness thereof is preferably about 0.55 mm, and when the body portion is formed in a flat shape, up to 0.4 mm is possible.

The protrusion 22 is formed integrally with the middle portion 22 at the lower side of the middle portion 22, and protrudes about 0.15 mm. The 0.15 mm is typically the minimum distance that the dome switch 51 can come into contact with the contact. In this embodiment, since the projection is made of a hard material, the deformation of the projection itself is virtually not sufficient, so that the dome switch 51 has a sufficient dome. The switch can be pressed to contact the contacts.

It is preferable that these protrusions 22 form the curved surface shape. The reason for this is to improve moldability in consideration of being manufactured integrally.

The key button 20 is preferably made of a synthetic resin material of high hardness than the silicone or rubber as a whole, specifically, the synthetic resin material is polycarbonate (PC), styrene (ABS), PC / ABS or polymeth It is preferable to include any one of methacrylate (PMMA). The key button 20 is manufactured integrally by injection molding, whereas in the prior art, only a part corresponding to the body portion 21 in the present embodiment is manufactured as the key button 20, whereas in the present embodiment, the body The part 21 and the projection 22 are characterized in that they are made integrally together.

In general, when the thickness of the protrusion is about 0.15 mm, the dome switch may be brought into contact with the contact point. However, in the related art, since the protrusion is made of a flexible polyurethane material, the protrusion itself is compressed when the dome switch is pressed. It should be at least 0.2 to 0.25 mm. However, in the present embodiment, as the material of high hardness is manufactured as a projection, there is an advantage that the thickness increase considering its own elastic deformation is not necessary.

The sheet 30 is attached to the upper side of the frame 40 while covering the through hole 41 of the frame 40. Such a sheet 30 is preferably a flexible film that is flexible and not easily torn. Specifically, the material is preferably used as a material such as polyurethane (PU), polypropylene (PP), silicone, or polyester (PET), but is not limited thereto.

Meanwhile, the seat 30 is elastically deformed so that the key button 20 can press the dome switch 51 while the key button 20 is pressed, or the key button 20 is returned to its original position. It is preferable to have elasticity and to have a minimum strength since the thickness is at least 0.25 mm.

On the other hand, the sheet is attached so that the portion corresponding to the two of the key button surrounds the surface of the projection. That is, the sheet is attached so as to surround the entire surface of the projection, and the projection may form a curved surface with a smooth edge, thereby maintaining the adhesive force between the sheet and the projection. If the protrusion has an angular corner shape, a problem may occur in some areas such that the protrusion between the protrusion and the sheet may not be securely formed or the sheet may fall off from the protrusion in the course of operating the key button.

The frame 40 is made of a metal material, but in the form of a thin plate. The frame 40 maintains the rigidity of the keypad as a whole so that the key button 20 can be kept horizontal. The frame 40 is disposed on an upper position corresponding to the plurality of dome switches 51. The material of the frame 40 is not limited to a metal material as long as the material has rigidity, and various materials may be used. For example, synthetic resin materials such as polycarbonate (PC) and polyethylene terephthalate (PET) may be used. Bonding between the frame and the sheet is made by an adhesive, but the adhesive may be applied to the entire lower surface of the frame at the joint between the frame and the sheet, but only a central portion may be applied.

The keypad manufactured as described above may be operated as follows.

First, as shown in FIG. 4, when the user presses the key button 20 with a finger, the seat 30 is deformed so that the dome switch 51 comes into contact with the contact 52. That is, the user recognizes a letter or number formed on the upper side of the key button 20 to select a predetermined desired key button 20, thereby pressing the key button 20. Accordingly, the key button 20 is lowered while being supported by the seat 40 so that the seat area corresponding to the protrusion presses the dome switch downward. As such, when the dome switch contacts the contact while the dome switch is pressed, the lowering of the key button may stop and a predetermined electric signal may be generated. Accordingly, a desired operation function is performed.

On the other hand, if the user's finger is removed from the key button 20, the elongated seat 30 is restored to its original state while the key button 20 is raised to return to the original position.

Such a keypad can be manufactured as follows.

Firstly, a key button manufacturing step of providing a key button in which protrusions for pressing the dome switch are integrally formed is performed. That is, as shown in FIG. 5, the upper mold 70 and the lower mold 71, but the mold is prepared so that the cavity of the shape corresponding to the key button is formed therebetween, and the molten state in the cavity Synthetic resin material 20a is injected to cure. When curing is completed, the key button is removed from the mold.

Thereafter, a frame attaching step of attaching the sheet 40 to the frame 30 provided with the plurality of through holes 31 to cover the through holes 31 is performed. In this case, a predetermined adhesive may be applied to the lower surface of the frame 30 or the upper surface of the sheet 40, and both may be adhered to each other as the frame 30 and the sheet 40 contact each other. However, the adhesive method is not limited thereto, and various materials may be used.

Subsequently, a key button attaching step of attaching each key button 20 to each position corresponding to the through hole 31 is performed on the upper side of the sheet 40.

The key button attaching step is composed of an application step, an adhesion step, a curing step. The application step is to apply a UV curable paste on the upper surface of the sheet 40 or the lower surface of the key button 20, it may be applied to both or only one.

The close contacting step is a step of bringing the upper surface of the sheet 40 and the lower surface of the key button 20 into close contact with each other. This adhesion step is composed of the attachment mold preparation step, position alignment step and entry step.

The attachment mold preparation step is to prepare an attachment mold 80 as shown in FIG. At this time, the attachment mold 80, the upper surface has a flat surface corresponding to the lower surface of the sheet ($ 0), when the key button 20 is raised, the key 22 on which the projection 22 of the key button 20 is placed The insertion groove 81 having a shape corresponding to the protrusion 22 is formed only at a position corresponding to the protrusion of the button.

In the alignment step, the sheet 40 and the key button 20 to which the frame 30 is attached to the attachment mold 80 are sequentially stacked, but the protrusions 22 of the key button 20 are inserted into the insertion grooves ( 81).

The entry step is to press the laid key button 20 to the lower side so that the projection 22 of the key button 20 enters into the insertion groove 81 together with the seat 40.

As such, when the close step is completed, the curing step is performed. In the curing step, as shown in FIG. 8, after the ultraviolet irradiation means 90 is positioned on the opposite side of the key button with the attachment mold 80 interposed therebetween, the ultraviolet irradiation means 90 irradiates the ultraviolet rays from the ultraviolet irradiation means 90. This step is to allow the UV curable paste to cure. At this time, the irradiated ultraviolet rays pass through the attachment mold 80 and the sheet 40 to reach the UV curable paste between the sheet 40 and the coverton 20.

On the other hand, the sheet 40 and the attachment mold 80 is preferably used as a transparent material so that the ultraviolet light can penetrate. In particular, the attachment mold 80 may be used a variety of materials, such as glass and other transparent synthetic resin material.

Such a slim keypad according to the present invention and a method of manufacturing the same may be modified as follows.

First, in the above-described embodiment, the UV curable paste is used to adhere the sheet and the key button to each other, but the present invention is not limited thereto, and various adhesives may be used.

In addition, in the above-described embodiment, the contact mold is used to make sure contact between the sheet and the key button, but the present invention is not limited thereto. It is also possible to bond.

In addition, in the above-described embodiment, the key button in which the protrusions are integrally described has been described, but the present invention is not limited thereto, and a separate protrusion may be attached to form the key button.

In the above, embodiments of the slim keypad for a mobile communication terminal according to the present invention have been described, but the present invention is not limited thereto, and various modifications can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Belongs to the present invention.

1 is a view showing a keypad for a mobile communication terminal according to the prior art.

2 is an operation of FIG.

3 is a view showing a keypad for a mobile communication terminal according to an embodiment of the present invention.

4 is an operation of FIG.

5 to 8 are views showing a process of manufacturing the keypad for the mobile communication terminal of FIG.

<Detailed Description of Drawings>

10 ... Slim Keypad 20 ... Key Button

21 ... Body 22 ... Protrusion

30 ... frame 40 ... sheet

Claims (9)

A keypad for a mobile communication terminal for pressing a dome switch to contact a contact, A frame provided with a plurality of through holes at a position corresponding to the dome switch; A sheet disposed to cover the through hole and attached to a lower side of the frame; And It is disposed in a position corresponding to the through hole and attached to the upper side of the sheet, It includes a key button that is pushed by the user to be moved downwards, protruding projections for pressing the dome switch on the bottom surface; The portion corresponding to the projection of the key button in the seat is attached to surround the surface of the projection slim keypad for a mobile communication terminal. The method of claim 1, The key button is a slim keypad for a mobile communication terminal, characterized in that made of a high hardness synthetic resin material than silicon or rubber. The method of claim 2, The synthetic resin material, a slim keypad for a mobile communication terminal comprising any one of PC, ABS, PC / ABS or PMMA. The method of claim 1, The protrusion is a slim keypad for a mobile communication terminal, characterized in that the curved surface has a smooth shape. A method of manufacturing a slim keypad for a mobile communication terminal according to claim 1, A key button manufacturing step of providing a key button in which a projection for pressing the dome switch is integrally formed; A frame attaching step of attaching a sheet to the frame provided with a plurality of through holes to cover the through holes; And a key button attaching step of attaching each key button to a position corresponding to the through hole on the upper side of the sheet. The method of claim 5, The key button attaching step, An application step of applying a UV curable paste to an upper surface of the sheet or a lower surface of a key button; An adhesion step of bringing the upper surface of the sheet and the lower surface of the key button into close contact with each other; And And a curing step of bringing the sheet and the key button into contact with each other as the UV-curable paste is cured by irradiating ultraviolet rays. The method of claim 6, The adhesion step, An attachment mold preparation step of preparing an attachment mold having an upper surface thereof having a flat surface corresponding to the lower surface of the sheet but having an insertion groove having a shape corresponding to the protrusion only at a position corresponding to the protrusion of the key button; Stacking the sheet and the key button with the frame attached to the attachment mold in sequence, wherein the key button has a position alignment step of placing the protrusion at a position corresponding to the insertion groove; And pressing the key button downward so that the projection of the key button enters the insertion groove together with the seat. The method of claim 7, wherein The sheet and the attachment mold is a manufacturing method of a slim keypad for a mobile communication terminal, characterized in that made of a transparent material that can pass through ultraviolet rays. The method of claim 8, The curing step, And placing the ultraviolet irradiation means on the opposite side of the key button with the adhesion mold therebetween, irradiating the ultraviolet rays from the ultraviolet irradiation means so that the ultraviolet rays pass through the adhesion mold and the sheet to reach the UV curable paste. Method of manufacturing a slim keypad for a mobile communication terminal, characterized in that.

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