JP2011109545A - Keypad - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology of preventing a liquid crystal display screen from being easily damaged by reliably forming a space between the liquid crystal display screen and an input operation part, in relation to a keypad mounted on an input operation part of an electronic apparatus where a first housing including a liquid crystal display screen is connected to a second housing including the input operation part through a hinge. <P>SOLUTION: In this keypad 11, a cushioning projection 13a having a tip projecting from a key top 15 is formed at an outer peripheral position of the key top 15 of an elastic sheet 13, and an outer edge thereof is fixed to an outer rim of an operation opening without having a partitioning bar formed on a second housing to close the operation opening. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a keypad for a pushbutton switch mounted on an electronic device, and more particularly to a keypad used for a foldable device.

  Electronic devices such as notebook computers and mobile phones employ a folding structure that can reduce the overall size of the device for convenience of carrying. In this folding structure, there are many cases in which a housing provided with an input operation unit using a push button switch and a housing provided with a liquid crystal display screen overlap each other so that the input operation unit and the liquid crystal display screen face each other. Specifically, the two casings are connected by a hinge that can be freely opened and closed, and the input operation unit and the liquid crystal display screen are closed to face each other when not in use.

  In such a folding structure, when the casing is closed, a projection that forms a gap on the opposite surface side of the casing to prevent the liquid crystal display screen from colliding with the input operation unit and avoiding damage. Is provided. Furthermore, a buffer member that absorbs an impact caused by a collision between the protrusion and the casing when the casing is closed is provided on the opposite surface side of the casing. For example, in a foldable mobile phone disclosed in Japanese Patent Laid-Open No. 2001-292209 (Patent Document 1), a protrusion is provided on a casing portion around an input operation unit, and a casing around a liquid crystal display screen The portion is provided with a buffer member that comes into contact with the protrusion when the casing is closed.

  If the protrusion itself is formed of a buffer member, the protrusion can absorb the impact caused by the collision between the protrusion and the casing while forming a gap between the input operation unit and the liquid crystal display screen when the casing is closed. For example, JP-A-11-275191 (Patent Document 2), JP-A-2003-264617 (Patent Document 3), JP-A-2003-308753 (Patent Document 4), JP-A-2006-115163 (Patent Document) Document 5) In the foldable mobile phone disclosed, a protrusion that comes into contact with a casing having a liquid crystal display screen is integrally provided on an elastic sheet used in an input operation unit. In this way, the number of parts can be reduced as compared with the mobile phone described in Patent Document 1, and the mobile phone can be easily assembled.

JP 2001-292209 A JP 11-275191 A JP 2003-264617 A JP 2003-308753 A JP 2006-115163 A

  By the way, the protrusions described in Patent Documents 2 to 5 can absorb an impact as a buffer member when coming into contact with a casing having a liquid crystal display screen. However, since the elastic sheet used in the input operation unit is arranged inside the casing, the protrusion is formed to be elongated so as to penetrate the casing. Easy to bend. For this reason, a gap may not be formed between the liquid crystal display screen and the input operation unit, and the two may collide and damage the liquid crystal display screen.

  The present invention has been made against the background of the prior art as described above. That is, an object of the present invention is to provide a technique for forming a gap between a liquid crystal display screen and an input operation unit so that the liquid crystal display screen is hardly damaged.

In order to achieve the above object, the present invention is configured as follows.
That is, the operation surface side of an elastic sheet made of a rubber-like elastic body is mounted on an input operation unit of an electronic device that connects a first case having a liquid crystal display screen and a second case having an input operation unit by a hinge. A key sheet having a pressing operation portion that is pressed during an input operation, and having a pressing operation portion on the operation surface side of the elastic sheet. A key that is provided with a buffer protrusion whose tip protrudes from the pressing operation portion at the outer peripheral position, and the outer edge of the base sheet is fixed to the outer edge of the operation opening so as to close the operation opening without the partition rail provided in the second housing Provide a pad.

In the present invention, the base sheet is configured by laminating a surface sheet that has better abrasion resistance than the elastic sheet on the operation surface side of the elastic sheet. For this reason, it can be made hard to wear against repeated pressing operations, and sufficient strength and durability can be exhibited.
Further, the tip of the buffer projection provided on the operation surface side of the elastic sheet protrudes from the pressing operation portion. For this reason, when the first casing and the second casing are closed so that the liquid crystal display screen and the input operation section face each other, the buffer protrusion comes into contact with the first casing before the input operation section. And a gap can be formed between the liquid crystal display screen and the input operation unit. Therefore, the liquid crystal display screen and the input operation unit can be made difficult to collide, and the liquid crystal display screen can be made difficult to be damaged. Furthermore, when the buffer projection collides with the first housing, the shock due to the collision can be absorbed by the buffer projection, and the liquid crystal display screen can be hardly damaged due to the impact. And since this buffer protrusion is provided in the elastic sheet, the number of parts can be reduced and the assembly of an electronic device can be simplified.
Furthermore, the outer edge of the base sheet is fixed to the outer edge of the operation opening so as to close the operation opening without the partition rail provided in the second housing. For this reason, it is only necessary that the tip of the buffer projection protrudes from the pressing operation portion without penetrating the second housing, the height of the buffer projection can be lowered, and the tip of the buffer projection collided with the first housing. At this time, it is possible to make the buffer protrusion difficult to fall and bend easily. According to the buffer protrusion, a gap can be surely formed between the liquid crystal display screen and the input operation unit, and the liquid crystal display screen can be hardly damaged.

  The buffer protrusion may have an inclined surface that gradually decreases from the proximal end toward the distal end. If the base end side of the buffer protrusion is widened in this way, when the tip of the buffer protrusion collides with the first housing, the buffer protrusion can be hardly tilted and bent, and the liquid crystal display screen and the input operation unit can be prevented from being bent. A gap can be reliably formed between them.

  The buffer protrusion may be provided in a ring shape surrounding the pressing operation unit. In this way, when the first casing and the second casing are closed, the pressing operation portion can be sealed by the first casing and the ring-shaped buffering protrusion, and when not in use, the dustproof and watertight The functions such as can be demonstrated.

  On the back surface opposite to the operation surface of the elastic sheet, a support portion that can contact the circuit board built in the second housing and support the buffer protrusion on the circuit board can be provided. In this way, when the front end of the buffer protrusion collides with the first housing, the support portion can close the space between the elastic sheet and the circuit board so that the buffer protrusion does not easily sink to the back side. A gap can be reliably formed between the screen and the input operation unit.

There can be two configurations for the tip side of the buffer protrusion.
First, the top sheet can cover the buffer protrusion. In this way, it is possible to make the buffer protrusion difficult to wear, and the durability of the buffer protrusion can be enhanced. Further, the surface sheet can restrain the deformation of the buffer protrusion, and when the tip of the buffer protrusion collides with the first housing, the buffer protrusion can hardly fall and bend easily. Therefore, a gap can be surely formed between the liquid crystal display screen and the input operation unit even when folding is repeatedly opened and closed.

  With respect to the keypad in which the surface sheet covers the buffer protrusion, the surface of the surface sheet that covers the front end side of the buffer protrusion can be an uneven surface. In this way, when the first housing and the second housing are closed, the contact area between the first housing and the buffer protrusion can be reduced, and the buffer protrusion contacts the first housing. It is possible to make it difficult to keep a mark.

  Secondly, a through-hole is provided in the top sheet, and the buffer protrusion penetrates into the through-hole to expose the tip side. In this way, when the first housing and the second housing are closed, the first housing and the buffer protrusion directly collide, so that the impact sound can be reduced.

  The keypad as described above may further include a reinforcing member that makes the elastic sheet difficult to bend. In this way, the base sheet can be made difficult to bend due to the rigidity of the reinforcing member, and a reliable pressing operation can be performed. In addition, the keypad with increased rigidity by the reinforcement member can have high strength against repeated pressing operations even when it is mounted on a casing without a partition rail in the operation opening. An operation unit can be realized.

  About a reinforcement member, it can be set as the frame shape which consists of a metal or resin. If the reinforcing member is made of metal or resin, the base sheet can be made difficult to bend with high rigidity. If the pressing operation portion is aligned with the frame-shaped opening, the pressing operation portion can hardly receive the rigidity of the reinforcing member during the pressing operation, and the pressing operability can be hardly deteriorated.

  With respect to the keypad including the reinforcing member, the reinforcing member is provided between the elastic sheet and the surface sheet, and an opening lip provided in the reinforcing member through which the buffering protrusion penetrates is formed on the buffering protrusion. It can be engaged with an engaging groove provided on the side surface. In this way, it is possible to make it difficult for the reinforcing member and the elastic sheet to be detached due to the engagement between the opening of the reinforcing member and the buffer protrusion of the elastic sheet, and it is possible to realize a keypad that can be easily attached to the housing. it can.

  About the said keypad provided with a reinforcement member, a reinforcement member can be embed | buried inside an elastic sheet. In this way, it is possible to prevent the reinforcing member and the elastic sheet from being detached, and it is possible to realize a keypad that can be easily attached to the housing.

  As for the keypad as described above, the elastic sheet has translucency, and the buffer protrusion has an illumination function of illuminating with an internal light source built in the second housing. In this way, parts other than the pressing operation part can be illuminated, and a new design can be realized.

  About the said keypad, the decoration layer can be provided in the back surface of a surface sheet. If it does in this way, a press operation part and a buffer projection can be decorated. And since the decoration layer is provided in the back surface of the surface sheet, it does not wear at the time of pressing operation, but can improve durability of decoration.

According to the keypad of the present invention, it is possible to make it difficult to wear the base sheet against repeated pressing operations, and to exhibit sufficient strength and durability.
Further, when the first housing and the second housing are closed, the buffer projection can be brought into contact with the first housing before the input operation unit, and the liquid crystal display screen and the input operation unit can be brought into contact with the buffer projection. A gap can be formed between the two. For this reason, it is possible to make it difficult for the liquid crystal display screen and the input operation unit to collide with each other, and it is possible to make the liquid crystal display screen difficult to be damaged. Further, the shock due to the collision between the first housing and the buffer protrusion can be absorbed by the buffer protrusion, and the liquid crystal display screen can be made less likely to fail due to the shock. Since the buffer protrusion is provided on the elastic sheet, the number of parts can be reduced, and the assembly of the electronic device can be simplified.
Furthermore, it is only necessary that the tip of the buffer projection protrudes from the pressing operation portion without penetrating the second housing, the height of the buffer projection can be lowered, and the tip of the buffer projection collided with the first housing. At this time, it is possible to make the buffer protrusion difficult to fall and bend easily. According to the buffer protrusion, a gap can be surely formed between the liquid crystal display screen and the input operation unit, and the liquid crystal display screen can be hardly damaged.

The top view which shows the keypad of 1st Embodiment. FIG. 3 is a sectional view taken along line SA-SA in FIG. 1. SB-SB sectional view taken on the line of FIG. FIG. 3 is a cross-sectional view corresponding to FIG. 2 illustrating a keypad according to a second embodiment. FIG. 4 is a cross-sectional view corresponding to FIG. 3 illustrating a keypad according to a second embodiment. The top view which shows the reinforcement member used for the keypad of 2nd Embodiment. The principal part enlarged plan view which shows the modification 1 of the reinforcement member in the keypad of 2nd Embodiment. The principal part expanded sectional view which shows the modification 2 of the reinforcement member in the keypad of 2nd Embodiment. The principal part expanded sectional view which shows the modification 3 of the reinforcement member in the keypad of 2nd Embodiment. The principal part expanded sectional view which shows the modification 1 common to the keypad of 1st, 2nd embodiment. The principal part expanded sectional view which shows the modification 2 common to the keypad of 1st, 2nd embodiment. The top view which shows the modification 3 common to the keypad of 1st, 2nd embodiment. SC-SC sectional view taken on the line of FIG. FIG. 5 is a cross-sectional view corresponding to FIG. The top view which shows the modification 5 common to the keypad of 1st, 2nd embodiment. SD-SD sectional view taken on the line of FIG. The SE-SE sectional view taken on the line of FIG. Sectional drawing equivalent to FIG. 2 which shows the keypad of 3rd Embodiment. FIG. 4 is a cross-sectional view corresponding to FIG. 3 illustrating a keypad according to a third embodiment. The top view which shows the surface sheet used for the keypad of 3rd Embodiment. The top view which shows the surface sheet used for the modification of the keypad in 3rd Embodiment.

  The present invention will be described in more detail with reference to the drawings. In this embodiment, a keypad used for a pushbutton switch of a foldable mobile phone will be described as an example. In addition, the same reference numerals are assigned to configurations common to the embodiments, and redundant description is omitted, and redundant descriptions of common materials, functions, effects, manufacturing methods, and the like are also omitted.

First Embodiment (FIGS. 1 to 3) :
A keypad 11 of the first embodiment is shown in FIGS. 1 is a plan view of the keypad 11, FIG. 2 is a sectional view taken along the line SA-SA of the keypad 11, and FIG. 3 is a sectional view taken along the line SB-SB of the keypad 11. The keypad 11 of the present embodiment includes a base sheet 14 on which the top sheet 12 and the elastic sheet 13 are stacked, and a key top 15 as a “pressing operation unit”.

The top sheet 12 is a member that has higher wear resistance than an elastic sheet 13 described later and reinforces the base sheet 14, and forms the operation surface side of the base sheet 14. The surface sheet 12 is formed with a covering portion 12 a that covers the buffer protrusion 13 a of the elastic sheet 13.
The surface sheet 12 is made of a material that can be bent and stretched following the elastic deformation of the elastic sheet 13. For example, a resin film, a thermosetting rubber, and a thermoplastic elastomer can be used. Of these, urethane rubber and urethane resin are preferred because of their excellent durability and wear resistance.

The elastic sheet 13 is a member that enables elastic deformation and shape recovery of the base sheet 14, and forms a back side opposite to the operation surface of the base sheet 14. The elastic sheet 13 is provided with a buffer protrusion 13 a whose tip protrudes from the key top 15 at the outer peripheral position of the key top 15 group on the operation surface side. In addition, if the front end side of the buffer protrusion 13a is rounded, the housing that contacts the buffer protrusion 13a can be made difficult to be damaged.
The material of the elastic sheet 13 is a rubber-like elastic body that can be elastically deformed, and thermosetting rubber, thermoplastic elastomer, or the like is used. Examples of the thermosetting rubber include silicone rubber and ethylene propylene rubber, and examples of the thermoplastic elastomer include styrene elastomer, olefin elastomer, and polyester elastomer. In order to restore the shape by rubber elasticity, a thermosetting rubber having a small compression set is preferable, and a silicone rubber having a low temperature dependency is most preferable.

The key top 15 is a member serving as a pressing operation unit, and is fixed to the operation surface side of the base sheet 14.
The key top 15 is made of a material that can transmit the pressing force to the back side of the base sheet 14. For example, hard resin and rubber-like elastic body can be used.

A mobile phone equipped with the keypad 11 as described above will be described.
The keypad 11 is mounted on a second housing 2 connected to a first housing 1 having a liquid crystal display screen (not shown) by a hinge (not shown). As shown in FIG. 3, the outer edge of the base sheet 15 is covered with an outer opening in the operation opening 2 a with an adhesive or an adhesive not shown in the figure so as to close the operation opening 2 a without a partition rail provided in the second housing 2. It is fixed to the edge step 13b. And if the 1st housing | casing 1 and the 2nd housing | casing 2 are closed, the 1st housing | casing 1 will contact | abut to the front-end | tip of the buffer protrusion 13a.

Next, an example of a method for manufacturing the keypad 11 will be described.
First, the surface sheet 12 is inserted into the molding die of the elastic sheet 13, and the base sheet 14 is formed by integrally molding the surface sheet 12 and the elastic sheet 13. The cavity surface on the insert side of the topsheet 12 in this molding die is provided with a recess for forming the buffer protrusion 13a. When the buffer protrusion 13a is formed as a recess, the surface sheet 12 is curved along the recess to simultaneously form the covering portion 12a of the surface sheet 12 that covers the buffer protrusion 13a. Next, the base sheet 14 is removed, and the key top 15 is fixed to the top sheet 12 side. In this way, the keypad 11 can be obtained.
In addition, before inserting the surface sheet 12, the coating | coated part 12a can also be formed in the surface sheet 12 previously. In this way, the three-dimensional shape of the covering portion 12a can be easily formed, and the buffer protrusion 13a can be easily formed in an accurate shape.

The operation and effect of the keypad 11 will be described.
According to the keypad 11, since the surface sheet 12 forms the operation surface side of the base sheet 14, it can be made difficult to wear against repeated pressing operations, and exhibits sufficient strength and durability. Can do.
Further, since the tip of the buffer protrusion 13a protrudes from the key top 15, the buffer protrusion before the key top 15 with respect to the first housing 1 when the first housing 1 and the second housing 2 are closed. 13 a can be brought into contact, and a gap can be formed between the liquid crystal display screen and the key top 15. Therefore, the liquid crystal display screen and the key top 15 can be made difficult to collide, and the liquid crystal display screen can be made difficult to be damaged. Furthermore, when the buffer protrusion 13a collides with the first housing 1, the shock due to the collision can be absorbed by the buffer protrusion 13a, and the liquid crystal display screen can be prevented from malfunctioning due to the shock. Since the buffer protrusion 13a is provided on the elastic sheet 13, the number of parts can be reduced, and the assembly of the mobile phone can be simplified.
Furthermore, since the outer edge of the base sheet 14 is fixed to the step 2b of the operation opening 2a provided in the second casing 2, the height of the buffer protrusion 13a is lower than that of the conventional protrusion penetrating the casing. When the front end of the buffer protrusion 13a collides with the first housing 1, the buffer protrusion 13a can be hardly fall down and bendable. According to the buffer protrusion 13a, a gap can be reliably formed between the liquid crystal display screen and the key top 15, and the liquid crystal display screen can be hardly damaged.

  Since the covering portion 12a of the surface sheet 12 covers the buffer protrusion 13a, it is possible to make the buffer protrusion 13a difficult to wear and to improve the durability of the buffer protrusion 13a. Furthermore, the covering portion 12a of the surface sheet 12 can restrain the deformation of the buffer protrusion 13a, and when the tip of the buffer protrusion 13a collides with the first housing 1, the buffer protrusion 13a is unlikely to fall down and bend easily. it can. Therefore, a gap can be reliably formed between the liquid crystal display screen and the key top 15 even when the folding is repeatedly opened and closed.

Second Embodiment [FIGS. 4 to 6] :
A keypad 21 of the second embodiment is shown in FIGS. 4 is a cross-sectional view corresponding to FIG. 2 of the keypad 21, FIG. 5 is a cross-sectional view corresponding to FIG. 3 of the keypad 21, and FIG. 6 is a plan view of the reinforcing member 26 used in the keypad 21. The keypad 21 of this embodiment is different from the keypad 11 of the first embodiment in that the configuration of the elastic sheet 23 and a reinforcing member 26 are provided. Other configurations are the same as those of the keypad 11.

  Similarly to the elastic sheet 13, the elastic sheet 23 is provided with a buffer protrusion 23 a whose tip protrudes from the key top 15 at the outer peripheral position of the key top 15 group on the operation surface side. The difference from the elastic sheet 13 is that a convex portion 23b that fills an opening 26a of a reinforcing member 26 described later is formed.

The reinforcing member 26 is a member that makes the base sheet 24 including the top sheet 12 and the elastic sheet 23 difficult to bend, and is sandwiched between the top sheet 12 and the elastic sheet 23. The reinforcing member 26 is formed in a frame shape having a plurality of openings 26 a with the same outer shape as the top sheet 12. The sizes of the openings 26a are substantially the same as the projection areas of the buffer protrusions 23a provided on the key top 15 and the elastic sheet 23, as shown in FIG. Thus, if the opening 26a is aligned with the position where the key top 15 is provided, the elastic sheet 23 can be easily elastically deformed during the pressing operation. If the opening 26a is aligned with the position of the buffer projection 23a, the buffer projection 23a and the covering portion 12a of the topsheet 12 can be formed simultaneously when the elastic sheet 23 is molded as will be described later.
As the material of the reinforcing member 26, a material having rigidity capable of supporting the shape of the base sheet 24 and suppressing the bending can be used. For example, a metal, resin, etc. are mentioned. Examples of the metal include a single material such as iron, aluminum, and copper, or alloys containing the same. Examples of the resin include polyethylene terephthalate resin, polycarbonate resin, and acrylonitrile butadiene styrene resin.
In addition to the plate shape, the reinforcing member 26 may have a mesh structure, a woven fabric structure, a non-woven fabric structure, or the like. Further, depending on the structure of the keypad, the reinforcing member can have not only a flat shape but also a shape having irregularities.

  Next, an example of the manufacturing method of the keypad 21 will be described. First, the reinforcing member 26 having the top sheet 12 and the opening 26a is sequentially inserted into the molding die of the elastic sheet 23, and the top sheet 12, the reinforcing member 26, and the elastic sheet 23 are integrally formed to form the base sheet 24. . At this time, the covering portion 12a of the topsheet 12 is formed simultaneously with the formation of the buffer protrusion 23a. Next, the base sheet 24 is removed, and the key top 15 is fixed to the top sheet 12 side. In this way, the keypad 21 can be obtained.

  The operation and effect of the keypad 21 will be described. According to the keypad 21, the base sheet 24 can be made difficult to bend due to the rigidity of the reinforcing member 26, and a reliable pressing operation can be performed. Further, the keypad 21 whose rigidity is enhanced by the reinforcing member 26 as described above can have high strength against repeated pressing operations even when the keypad 21 is attached to the second housing 2 having no partition rail in the operation opening 2a. Thus, a highly durable keypad 21 can be realized.

  If the reinforcing member 26 is formed of metal or resin, the base sheet 24 can be made difficult to bend with high rigidity. Since the key top 15 is aligned with the opening 26a, the rigidity of the reinforcing member 26 can be made difficult to be pressed against the pressing of the key top 15 during the pressing operation, and the pressing operability can be hardly deteriorated.

  As for the keypad 21 of the second embodiment, a modification by the reinforcing member 26 can be given.

Modification 1 with reinforcing member (FIG. 7) :
In the first modification of the reinforcing member 26, as shown in FIG. 7, a bridging portion 26b can be provided in the opening 26a aligned with the buffer protrusion 23a.
In this way, it is possible to make it difficult for the bridging portion 26b to penetrate the convex portion 23b and to remove the elastic sheet 23 and the reinforcing member 26 from each other.

Modification 2 with reinforcing member (FIG. 8) :
In the second modification of the reinforcing member 26, the reinforcing member 26 can be embedded in the elastic sheet 23 as shown in FIG.
In this way, it is possible to prevent the reinforcing member 26 and the elastic sheet 23 from being detached, and it is possible to realize the keypad 21 that can be easily attached to the second housing 2.
Further, in combination with the first modification, the reinforcing member 26 provided with the bridging portion 26 b can also be embedded in the elastic sheet 23.

Modification 3 with reinforcing member (FIG. 9) :
In Modification 3 of the reinforcing member 26, as shown in the enlarged view of the main part in FIG. 9, the lip of the opening 26a provided in the reinforcing member 26 is provided on the side surface of the buffer projection 23a in the elastic sheet 23. It can be engaged with the mating groove 23c.
By doing so, it is possible to make it difficult for the reinforcing member 26 and the elastic sheet 23 to be detached due to the engagement between the opening 26 a of the reinforcing member 26 and the engaging groove 23 c of the elastic sheet 23. A keypad 21 that is easy to attach can be realized.

  Next, a modification common to the first and second embodiments will be described. In the drawings, a modification of the keypad 11 of the first embodiment will be described.

Modification 1 common to the first and second embodiments (FIG. 10) :
In the keypads 11 and 21, the base end sides of the buffer protrusions 13 a and 23 a in the elastic sheets 13 and 23 are formed so as to rise substantially perpendicular to the sheet surfaces of the base sheets 14 and 24. As shown in the enlarged view of the main part of FIG. 10, the first keypad 31 can be configured such that the buffer protrusion 33 a of the elastic sheet 33 rises with an inclined surface that gradually decreases from the base end toward the tip end. The covering portion 32a of the top sheet 32 also has an inclined surface.
In this way, when the tip of the buffer projection 33a collides with the first housing 1, it is possible to make the buffer projection 33a difficult to fall and bend, and reliably between the liquid crystal display screen and the key top 15. A gap can be formed.

Modification 2 common to the first and second embodiments (FIG. 11) :
In the keypads 11 and 21, the tips of the buffer protrusions 13 a and 23 a of the elastic sheets 13 and 23 are formed in a round shape, but the keypad 41 of the common modification 2 is as shown in the enlarged view of the main part in FIG. 11. In addition, the front end of the buffer protrusion 43a in the elastic sheet 43 and the covering portion 42a of the topsheet 42 that covers the front end can be made uneven.
In this way, when the first housing 1 and the second housing 2 are closed, the contact area between the first housing 1 and the covering portion 42a covering the buffer protrusion 43a can be reduced, and the first It is possible to make it difficult to attach the contact mark of the buffer protrusion 43 a to the housing 1.

Modification 3 common to the first and second embodiments (FIGS. 12 and 13) :
In the keypads 11, 21, the buffer protrusions 13 a, 23 a of the elastic sheets 13, 23 are provided at one place on the outer peripheral position of the key top 15 group. As shown in FIG. 8, the buffer protrusion 53a of the elastic sheet 53 and the covering portion 52a of the surface sheet 52 covering the buffer protrusion 53a can be provided in an annular shape surrounding the group of key tops 15.
In this way, when the first casing 1 and the second casing 2 are closed, the key top 15 can be sealed by the first casing 1 and the ring-shaped buffer protrusion 53a, and when not in use. It can exhibit functions such as dust proofing and watertightness.

Modification 4 common to the first and second embodiments (FIG. 14) :
In the keypads 11, 21, the back surfaces of the elastic sheets 13, 23 are formed as flat surfaces. However, as shown in FIG. 14, the common keypad 61 of Modification 4 has a second housing on the back surface of the elastic sheet 63. A support portion 63c that can contact the circuit board 3 incorporated in the body 2 and support the buffer protrusion 63a on the circuit board 3 can be provided.
In this way, when the tip of the buffer protrusion 63a collides with the first housing 1, the support portion 63c closes the space between the elastic sheet 63 and the circuit board 3 so that the buffer protrusion 63a is unlikely to sink to the back surface side. Thus, a gap can be surely formed between the liquid crystal display screen and the key top 15.
Note that the keypad 61 of Modification 4 can be combined with the keypads 31, 41, 51 of Modifications 1 to 3.

Modification 5 common to the first and second embodiments (FIGS. 15 to 17) :
In the keypads 11, 21, the flat surface of the topsheet 12 is exposed to the operation surface side, but the common keypad 71 of the modified example 5 is a flat surface of the topsheet 12 as shown in FIGS. 15 to 17. A top cover 77 is laminated on the top. The top cover 77 is formed in a frame shape having a plurality of openings 77 a with an outer shape equivalent to that of the top sheet 12. As shown in FIG. 15, the sizes of the openings 77a are substantially the same as the projection area of the covering portion 12a that covers the key top 15 and the buffer protrusion 13a.
The top cover 77 is fixed to the top sheet 12. For example, if the peripheral portion of the opening 77 a through which the key top 15 penetrates is not fixed, the elastic sheet 13 is moved by the top cover 77 when the key top 15 is pressed. The elastic pressing operation can be facilitated without being restricted. Further, if the peripheral portion of the opening 77a through which the buffer protrusion 13a penetrates is fixed, the top cover 77 can support the buffer protrusion 13a from the periphery, and the buffer protrusion 13a can be prevented from falling down or being laterally displaced.
Note that the keypad 71 of Modification 5 can be combined with the keypads 31, 41, 51, 61 of Modifications 1 to 4.

Third Embodiment (FIGS. 18 to 20) :
A keypad 81 of the third embodiment is shown in FIGS. 18 is a cross-sectional view corresponding to FIG. 2 of the keypad 81, FIG. 19 is a cross-sectional view corresponding to FIG. 3 of the keypad 81, and FIG. 20 is a plan view of the surface sheet 82 used for the keypad 81. The keypad 81 of the present embodiment is different from the keypad 11 of the first embodiment in the configuration of the topsheet 82. Other configurations are the same as those of the keypad 11.

  Similar to the surface sheet 12, the surface sheet 82 is laminated with the elastic sheet 83 to form the operation surface side of the base sheet 84. The top sheet 12 is different from the top sheet 12 in that there is no covering portion covering the buffer protrusion 83a, a through hole 82b is provided, the buffer protrusion 83a penetrates into the through hole 82b, and the tip side is exposed from the top sheet 82. is there.

  Next, an example of a method for manufacturing the keypad 81 will be described. First, the surface sheet 82 having the through holes 82b is inserted into the molding die of the elastic sheet 83, and the surface sheet 82 and the elastic sheet 83 are integrally molded to form the base sheet 84. At this time, the buffer protrusion 83 a is formed so as to penetrate into the through hole 82 b of the top sheet 82. Next, the base sheet 84 is removed from the mold, and the key top 15 is fixed to the surface sheet 82 side. In this way, the keypad 81 can be obtained.

  The operation and effect of the keypad 81 will be described. According to the keypad 81, since the buffer protrusion 83a penetrates into the through hole 82b of the top sheet 82 and exposes the leading end side, the first housing 1 and the second housing 2 are closed when the first housing 1 and the second housing 2 are closed. Since the housing 1 and the buffer protrusion 83a directly collide with each other, the impact sound can be made smaller than when the housing 1 collides with the top sheet.

Modification of the third embodiment :
The keypad 81 can also include the reinforcing member 26 like the keypad 21 (see FIGS. 4 to 6), and can be combined with each modification of the reinforcing member 26.
Furthermore, a modification similar to the keypads 11 and 21 can be configured. For example, the buffer protrusion can be raised on an inclined surface that gradually narrows from the proximal end to the distal end (see FIG. 10). The tip of the buffer protrusion can be an uneven surface (see FIG. 11). The buffer protrusion can be provided in a ring shape surrounding the key top group (see FIGS. 12 and 13). A support portion that can support the buffer protrusion on the circuit board can be provided on the elastic sheet (see FIG. 14). However, when the buffer protrusions are provided in a ring shape, a plurality of through holes 82b along the buffer protrusions are formed on the top sheet 82 as shown in FIG.
Each of these modifications exhibits the same operations and effects as described above.

Modification common to each embodiment and each modification :
The keypads 11, 21, 31, 41, 51, 61, 71, 81 can be configured with the following common modifications.

A 1st structure can provide a decoration layer in the back surface of the surface sheets 12, 32, 42, 62, and 82. FIG.
In this way, the key top 15 and the buffer protrusions 13a, 23a, 33a, 43a, 53a, 63a, 83a can be decorated. And since the decoration layer is provided in the back surface of the surface sheets 12, 32, 42, 62, and 82, it does not wear at the time of pressing operation, but can improve durability of decoration.

In the second configuration, if the surface sheets 12, 32, 42, 62, 82 and the elastic sheets 13, 23, 33, 43, 53, 63, 83 are formed of a translucent material, they are built in the second housing. The buffer projections 13a, 23a, 33a, 43a, 53a, 63a, 83a can be illuminated by the internal light source.
In this way, portions other than the key top 15 can be illuminated, and a new design can be realized.

In the third configuration, the key top 15 can be eliminated and a flat pressing operation unit can be obtained.
In this way, the buffer protrusion can be formed low, and a thin keypad can be realized.

  Hereinafter, the present invention will be described in detail with reference to examples.

Sample 1 :
A polyester urethane film having a thickness of 0.05 mm was used as the top sheet (12), and a coating layer was printed on the back surface to form a decorative layer. Silicone rubber was used for the elastic sheet (13), and the base sheet (14) was formed by integrating the surface sheet (12) and the elastic sheet (13) in a mold. At this time, the topsheet (12) was softened along the cavity shape provided in the mold, and the covering portion (12a) was simultaneously formed together with the buffer protrusion (13a). The base sheet (14) was removed from the mold, and a key top (15) made of a polycarbonate resin was fixed to a desired position on the operation surface side of the top sheet (12) with an adhesive. Thus, a sample 1 of the keypad (11) was obtained.

Sample 2 :
Similarly to Sample 1, a base sheet (14) was formed by integrating a surface sheet (12) of a polyester urethane film having a thickness of 0.05 mm and an elastic sheet (13) made of silicone rubber. The base sheet (14) is removed, and a top cover (77) made of a polycarbonate resin film having a thickness of 0.25 mm and a key top (15) made of a polycarbonate resin are provided on the operation surface side of the top sheet (12). Adhered to the desired position with an adhesive. In this way, Sample 2 as a modification of the keypad (11) was obtained.

Sample 3 :
Using a polyether urethane film with a thickness of 0.1 mm as the top sheet (12), a coating layer is printed on the back surface to form a decorative layer, and the top sheet (12) is formed into an uneven shape to form a covering portion (12a). Formed. A stainless steel plate having a frame shape in which an opening (26a) was formed was used as the reinforcing member (26). The reinforcing member (26) is formed such that the size of the opening (26a) aligned with the buffer protrusion (23a) is slightly smaller than the projection area of the buffer protrusion (23a). Silicone rubber is used for the elastic sheet (23), and the top sheet (12) having the covering portion (12a) formed in the mold and the reinforcing member (26) having the opening (26a) are sequentially inserted, The base sheet (24) was formed by integrating the top sheet (12), the reinforcing member (26), and the elastic sheet (23). At this time, the buffer protrusion (23a) is formed so as to fill the hollow covering portion (12a), and the edge of the opening (26a) in the reinforcing member (26) is provided on the side surface of the buffer protrusion (23a). Engage with the engaging groove (23b). The base sheet (24) was removed from the mold, and a key top (15) made of polycarbonate resin was fixed to a desired position on the operation surface side of the top sheet (12) with an adhesive. In this way, Sample 3 which is a modification of the keypad (21) was obtained.

Sample 4 :
A polyester urethane film having a thickness of 0.05 mm was used as the top sheet (82), and a coating layer was printed on the back surface to form a decorative layer. A through hole (82b) was formed at a position where the buffer protrusion (83a) was provided. Further, a frame-shaped aluminum plate in which an opening (26a) was formed was used as the reinforcing member (26). Silicone rubber is used for the elastic sheet (83), and a surface sheet (82) having a through hole (82b) in the mold and a reinforcing member (26) having an opening (26a) are sequentially inserted into the mold. The base sheet (84) was formed by integrating the top sheet (82), the reinforcing member (26), and the elastic sheet (83). At this time, the buffer protrusion (83a) was formed by penetrating the through hole (82b) of the top sheet (82). The base sheet (84) was removed from the mold, and a key top (15) made of polycarbonate resin was fixed to a desired position on the operation surface side of the top sheet (82) with an adhesive. In this way, Sample 4 which is a modification of the keypad (81) was obtained.

DESCRIPTION OF SYMBOLS 1 1st housing | casing 2 2nd housing | casing 2a Operation opening 2b Step part 3 Circuit board 11 Keypad (1st Embodiment)
12 surface sheet 12a covering part 13 elastic sheet 13a buffer projection 14 base sheet 15 key top 21 keypad (second embodiment)
23 Elastic sheet 23a Buffer projection 23b Protruding part 23c Engaging groove 24 Base sheet 26 Reinforcing member 26a Opening 26b Bridge part 31 Keypad (Modification 1 common to the first and second embodiments)
32 surface sheet 32a covering portion 33 elastic sheet 33a buffer projection 41 keypad (modification 2 common to the first and second embodiments)
42 surface sheet 42a covering portion 43 elastic sheet 43a buffer projection 51 keypad (modification 3 common to the first and second embodiments)
52 Surface sheet 52a Covering portion 53 Elastic sheet 53a Buffer projection 61 Keypad (Modification 4 common to the first and second embodiments)
63 Elastic sheet 63a Buffer projection 63c Support portion 71 Keypad (Modification 5 common to the first and second embodiments)
77 Top Cover 77a Opening 81 Keypad (Third Embodiment)
82 Surface sheet 82b Through hole 83 Elastic sheet 83a Buffer projection 84 Base sheet

Claims (10)

Mounted on the input operation unit of the electronic device that connects the first housing having the liquid crystal display screen and the second housing having the input operation unit by a hinge, and on the operation surface side of the elastic sheet made of a rubber-like elastic body A keypad having a base sheet for laminating a surface sheet that is more excellent in abrasion resistance than an elastic sheet, and having a pressing operation part that is pressed during an input operation,
Provided with a buffer protrusion whose tip protrudes from the pressing operation part at the outer peripheral position of the pressing operation part on the operation surface side of the elastic sheet,
A keypad in which the outer edge of the base sheet is fixed to the outer edge of the operation opening so as to close the operation opening without the partition rail provided in the second housing.   The keypad according to claim 1, wherein the buffer protrusion has an inclined surface that gradually becomes thinner from the proximal end toward the distal end.   The keypad according to claim 1, wherein the buffer protrusion is provided in a ring shape surrounding the pressing operation portion.   The support part which can contact a circuit board built in a 2nd housing | casing and can support a buffer protrusion on a circuit board is provided in the back surface opposite to the operation surface of an elastic sheet. Keypad as described.   The keypad according to claim 1, wherein the surface sheet covers the buffer protrusion.   The keypad according to claim 5, wherein the surface of the surface sheet covering the tip side of the buffer protrusion is an uneven surface.   The keypad according to any one of claims 1 to 4, wherein the top sheet is provided with a through-hole, and the buffer protrusion penetrates into the through-hole to expose the tip side.   The keypad according to claim 1, further comprising a reinforcing member that makes the base sheet difficult to bend. A reinforcing member is provided between the elastic sheet and the top sheet,
The keypad according to claim 8, wherein a lip of an opening provided in the reinforcing member and through which the buffering protrusion penetrates engages with an engaging groove provided on a side surface of the buffering protrusion.   The keypad according to claim 1, wherein the elastic sheet has translucency, and the buffer protrusion has an illumination function of illuminating with an internal light source built in the second housing.

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