JPH10268999A - Key input device and computer provided with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a key input device, with which a switch can be surely operated and further can be much more thinned, and a computer provided with the same. SOLUTION: This device is provided with a key top 11 for performing key inputs through pressing operation and an electric contact formed from a fixed electrode 7d and a movable electrode 7c, the movable electrode 7c is pressed onto the side of fixed electrode 7d by the pressing operation of key top and a gap between contacts is closed. In this case, an air chamber 12 for storing air is provided under the key top 11, one part of surrounding walls around the air chamber 12 is formed from a diaphragm 8a to be expanded corresponding to pressure increase inside the air chamber 12 and by performing the pressing operation of key top 11, the movable electrode 7c is pressed through the diaphragm 8a onto the side of fixed electrode 7d.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a key input device and a computer provided with the key input device.

[0002]

2. Description of the Related Art Conventionally, as a key input device such as a computer or a word processor, a key top is operated via a guide mechanism, a pantograph mechanism or a hinge mechanism when closing down an electric contact by depressing each key top. It is known that a contact pressing member below a keytop is pressed against an electric contact to close the contact. For example, Japanese Unexamined Utility Model Publication No. Hei 6-38358 discloses a technique in which a key top is connected to a surrounding frame portion via a hinge, and the key top is vertically rotated while being supported by the hinge. It has been disclosed. In recent years, in particular, portable computers such as notebook computers have been demanded to be further reduced in size and weight, and in particular to become thinner. As part of this, the key input devices have also been required to be made thinner. ing.

[0003]

However, in the case of using the above-mentioned conventional guide mechanism or pantograph mechanism, these mechanisms are provided between the key top and the electric contact in addition to the contact pushing member. Space is required, and it is difficult to achieve a sufficiently thin key input device. Further, even in the case of the hinge type, since at least the contact pressing member needs to be arranged below the key top (between the electric contact), there is still a limit to the reduction in thickness. Further, in the conventional method in which the electrical contact is pressed by a member (contact pressing member) mechanically connected to or engaged with the keytop, the operation force at the time of key input deviates to some extent from the central portion of the keytop. When it acts on the position (so-called one-sided pushing) or when acting from an oblique direction, the operating force is not sufficiently transmitted to the contact pushing member, and it is difficult to close the electric contact. That is, there is a problem that it is difficult to maintain the reliability of the switch operation with respect to the variation in the operation position or the direction of the operation force.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a key input device capable of reliably operating a switch and achieving further reduction in thickness, and a computer provided with the key input device.

[0005]

According to a first aspect of the present invention, there is provided a key top for performing a key input by a pressing operation, and an electric contact formed by a fixed electrode and a movable electrode. A key input device in which the movable electrode is pressed against the fixed electrode side by the pressing operation of the key input device so that the gap between the contacts is closed, and a fluid storage portion for storing a predetermined fluid below the key top is provided, A part of the peripheral wall of the fluid storage part is formed of a diaphragm that expands in response to a rise in pressure in the fluid storage part, and when the key top is pressed down, the movable electrode is connected to the fixed electrode through the diaphragm. It is characterized by being pressed against the side.

According to a second aspect of the present invention, in the first aspect, at least a skirt portion of the peripheral wall of the fluid storage portion, which falls from the key top side, is formed of a predetermined elastic material. The shape and thickness of the key top are set so that buckling deformation occurs when a pressing operation force of a predetermined value or more acts on the key top.

In a third aspect of the present invention, in the first or second aspect, an orifice having a predetermined throttle characteristic is provided on a peripheral wall of the fluid storing portion. is there.

Further, a fourth invention of the present application is characterized in that, in the third invention, each of the plurality of keys has a storage portion communicating with each other via the orifice. is there.

Further, according to a fifth invention of the present application, in the third or fourth invention, the fluid stored in the storage section is air, and the inner diameter d (m) of the orifice is
m) is characterized by being set so as to satisfy 0.42 ≦ d ≦ 0.75.

Here, the inner diameter d (m) of the orifice is
m) is set to 0.42 ≦ d ≦ 0.75 because, when the inner diameter d of the orifice is less than 0.42 (mm), when the key input operation speed is the maximum speed within the standard range, the diaphragm When the inner diameter d of the orifice exceeds 0.75 (mm), when the key input operation speed is the lowest speed within the standard range, This is because there is a possibility that the pressure lower than the lower limit of the pressure required for operating the switch for closing the electric contact may be obtained.

A sixth invention of the present application is characterized in that the computer includes the key input device according to the first to sixth inventions.

[0012]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a perspective view showing an example of a computer 1 according to an embodiment of the present invention. As shown in the figure, the computer 1 is, for example, a portable notebook type. On the other hand, the lid 4 is provided with a display unit 5 having, for example, a liquid crystal panel. 2, the key input device 3 includes a reinforcing plate 6, a membrane switch sheet 7, a lower rubber sheet 8, and an upper rubber sheet 9 which are sequentially stacked and fixed to each other using, for example, an adhesive. The key tops 11 of the operation key unit 10 corresponding to the key symbols such as letters, numbers, and symbols required for the key input operation are formed on the upper rubber sheet 9 with an adhesive, for example. It is fixed and configured.

The reinforcing plate 6 is made of, for example, metal and is mounted on the upper side of the main body housing 2 and serves to reinforce the key operation force applied to the key input device 3. In the present embodiment, for example, an aluminum plate material having a thickness of 0.8 [mm] is used as the reinforcing plate 6. Further, in the present embodiment, for example, an ABS (acrylonitrile / butadiene / styrene) resin is used as a material of the key top 11, and a material of the lower rubber sheet 8 and the upper rubber sheet 9 is, for example, hardness (Shore hardness). Sa)
Used a silicone rubber of about 50 degrees. The bonding between the key top 11 and the upper rubber sheet 9 and the bonding between the lower rubber sheet 8 and the upper rubber sheet 9 are performed, for example, using a silicone polymer-containing epoxy adhesive (for example, Bond MOS7 manufactured by Konishi Co., Ltd.). ) Was applied.

On the other hand, the membrane sheet 7 has the same cross-sectional structure as a conventionally well-known one, and a portion 7f below the keytop 11 is provided between the upper and lower two electrode sheets 7a and 7b. Except for the (space portion), a spacer 7e made of an electric insulating layer is interposed. The lower (fixed) electrode sheet 7b is entirely supported on the reinforcing plate 6, and a fixed electrode 7c that forms a part of a key input circuit (not shown) is disposed on the upper surface. On the other hand, the upper (movable) electrode sheet 7a is held between the spacer 7e and the lower rubber sheet 8 except for the portion corresponding to the space 7f, and the movable electrode 7d is disposed on the lower surface thereof. Have been.

In the present embodiment, the lower rubber sheet 8
And the upper rubber sheet 9 are adhered and fixed to each other to form an air chamber 12 below the keytop 11 as a fluid storage unit for storing a predetermined fluid (air (air) in the present embodiment). I have. That is, the peripheral wall of the air chamber 12 is constituted by upper and lower rubber sheets 9 and 8. The ceiling portion 9b of the upper rubber sheet 9 is provided with a plurality (for example, four) of stopper portions 9c in order to limit the maximum stroke (maximum key stroke) in the pressing operation of the key top 11. A part of the peripheral wall of the air chamber 12 (lower side wall)
A predetermined portion 8a (substantially the center portion in the present embodiment) of the lower rubber sheet 8 is formed to be very thin as compared with other portions, and this portion 8a responds to a rise in pressure in the air chamber 12. It constitutes an expanding diaphragm.
The position of the diaphragm 8a is set so as to correspond to the space 7f of the membrane switch sheet 7.

As shown in FIG. 3 or FIG. 4, when a depressing operation force F acts on the key top 11, the pressure in the air chamber 12 rises and the diaphragm 8a
Expands. Thus, the movable electrode sheet 7a is deformed toward the space 7f, and the movable electrode 7c is pressed against the fixed electrode 7d to come into contact therewith.
The contacts d are electrically connected. In the present embodiment, the shape and size of the diaphragm 8a are, for example,
The thickness was set to 0.25 [mm] in a circle having a diameter of 4 [mm]. The shape and size of the space portion 7f of the membrane switch sheet 7 also corresponded to the diaphragm 8a.

Further, in the present embodiment, the side wall 9a of the upper rubber sheet 9 formed of silicon rubber as an elastic material constitutes a skirt that falls down from the key top 11 side. In order to obtain a click feeling as a kind of moderation during key input operation, the skirt portion 9a
The shape and thickness are set such that buckling deformation occurs when a keystroke reaches a certain value due to a pressing operation force of a predetermined value or more acting on the key top 11. In the present embodiment, the shape and thickness of the skirt portion 9a are, for example, 65 degrees with respect to the upper surface of the lower rubber sheet 8, and the thickness Ts is 0.35 [mm]. The click characteristics in this case, that is, the buckling characteristics of the skirt portion 9a and the like will be described later.

Further, in this embodiment, the lower rubber sheet 8 is provided with an orifice 13 having a predetermined throttle characteristic, and the air chamber 12 is connected to the other key portion 10 through the orifice 13. Air chamber 12
Is in communication with As shown in FIG. 5, an air passage 14 is formed between the adjacent key portions 10 on the lower surface of the lower rubber sheet 8, and the orifice 13 is open to the air passage 14. That is, the air chambers 12 of the key portions 10 communicate with each other via the orifices 13 and the air passages 14. FIG.
Is a plan explanatory view of a part of the key input device 3, and as shown by a broken line in this figure, all the air chambers 12 of the respective key portions 10 are respectively provided through the respective orifices 13 and the air passages 14, respectively. The air chambers 12 of the adjacent key portions 10 communicate with each other, so that all the air chambers 12 communicate with each other.
A part of the air passage 14 is branched and communicates with an air vent hole 15 provided in, for example, a side surface of the main body housing 2.

In the above configuration, for example, as shown in FIG. 3, when a pressing operation force F acts on the key top 11, the pressure in the air chamber 12 increases, and the diaphragm 8a expands. As a result, the movable electrode sheet 7a is deformed toward the space portion 7f, and the movable electrode 7c is pressed against the fixed electrode 7d to come into contact therewith, so that the contact between the electrodes 7c and 7d is conducted and the switch is turned on. It has become. And, for example, as shown in FIG.
Even when the operation force F is applied to a position deviated from the center of the key top 11 (so-called single pressing), this operation force F is applied to the air in the same manner as when it is applied to the center of the key top 11 by the principle of Pascal. The diaphragm 8a is similarly expanded and the movable electrode 7c is pressed against the fixed electrode 7d, and the two electrodes 7c, 7
The contact between the contacts d is closed. In the operation of pressing down the key top 11, the stroke is a fixed value (set maximum value).
Is reached, the stopper portion 9c provided on the upper rubber sheet 9 abuts on the upper surface of the lower rubber sheet 8, whereby further downward displacement of the key top 11 is regulated. .

As described above, according to the present embodiment, when the key top 11 is pressed down, the pressure in the fluid reservoir (air chamber 12) provided below the key top 11 increases. The diaphragm 8a expands. Then, the movable electrode 7c is pressed against the fixed electrode 7d through the diaphragm 8a, and the electrical contact formed by the two is closed. Therefore, unlike the related art, there is no need to dispose a contact pressing member, a guide mechanism, a pantograph mechanism, or the like between the keytop and the electric contact, but only to provide the air chamber 12 for storing a predetermined fluid (air). As a result, the thickness of the key input device can be made much thinner than before. Also,
Even when the operation force F acts on a portion deviating from the center of the key top 11 or acts obliquely during the key input operation, the pressure rises substantially similarly in the air chamber 12 and the diaphragm 8a expands. Therefore, the key input operation can be performed more easily and surely. That is, it is possible to maintain the certainty of the switch operation with respect to variations in the operating position or direction of the operating force F.

Since an orifice 13 having a predetermined throttle characteristic is provided on the peripheral wall (lower rubber sheet 8) of the air chamber 12, a key input can be performed by appropriately setting the throttle characteristic of the orifice 13. During operation,
Air chamber 1 with key top 11 depressing operation
It is possible to appropriately adjust the rise in the pressure inside 2 and further improve the operation feeling. In addition, since the pressure in the air chamber 12 can be prevented from excessively increasing, damage to the diaphragm 8a can be prevented.

Further, in the present embodiment, the plurality of (all) keys 10 have their respective air chambers 12 communicating with each other through the orifice 13 and the air passage 14, so that one key top 11 is provided. When the operation force F is applied to the key 10, the air in the air chamber 12 can move into the air chamber 12 of another key 10. Therefore, it is possible to prevent the pressure in the air chamber 12 from unnecessarily increasing with a simple configuration, to obtain a good stroke feeling, and to reliably prevent the diaphragm 8a from being damaged.

Next, a description will be given of an appropriate range of the diameter of the orifice 13 which determines the aperture characteristic thereof. FIG. 7 shows that the center of the key top 11 is fixed at a constant speed v [mm
/ Sec.], The diameter d of the orifice 13 is varied (0.1 to 1.2).
(In the range of [mm]), and the maximum pressure [g / cm ² ] generated in the air chamber 12 was measured. 1.0, 1.5 [mm / sec.]). Here, the key input operation speed v =
0.5 [mm / sec.] Is the minimum speed when performing a standard input operation, and v = 1.5 [mm / sec.].
c.] is the maximum speed when performing a standard input operation. Also, the design value of the keystroke in the above measurement (maximum keystroke: that is, the stroke until the stopper 9c comes into contact with the upper surface of the lower rubber sheet 8)
The volume of the air chamber 12 (per one key portion 10) was as follows.・ Keystroke (design value): 1.5 [mm] ・ Air chamber volume (per key): 150 mm ³

As can be clearly understood from the graph of FIG.
For the same orifice diameter d, the lower the key input operation speed v, the lower the maximum pressure generated in the air chamber 12. On the other hand, regarding the maximum pressure [g / cm ² ] generated in the air chamber 12, the diaphragm 8a
From the viewpoint of strength, under the conditions of the material, thickness, and the like in the present embodiment, the upper limit value for damage due to internal pressure is 3%.
It cannot exceed 0 [g / cm ² ]. Further, from the viewpoint of the switch operation for closing the electric contact, 5 [g / c
m ² ] or more. Therefore, for a standard key input operation, the diameter d of the orifice 13 is 0.1 mm.
It may be set between 42 and 0.75 [mm]. In addition,
Considering that it is difficult to accurately control the operation speed in an actual key input operation, the diameter d of the orifice 13 is preferably in the range of 0.5 to 0.7 [mm]. . In the present embodiment, the orifice diameter d is set to, for example, 0.5 [mm].

In the present embodiment, as described above,
The side wall portion 9a of the upper rubber sheet 9 formed of silicon rubber as an elastic material constitutes a skirt portion falling from the key top 11 side, and a click feeling, which is a kind of moderation feeling accompanying the key input operation, is obtained. For the purpose, the shape and thickness of the skirt portion 9a
For example, an inclination angle β with respect to the upper surface of the lower rubber sheet 8 is set to 65 so that buckling deformation occurs when a keystroke reaches a predetermined value due to a pressing operation force equal to or more than a predetermined value.
The thickness Ts is set to 0.35 [mm]. The click feeling is obtained by the fact that the operating load increases with the progress of the pressing operation of the key top 11, and when reaching a certain limit value, the skirt portion 9a is buckled. In other words, the buckling of the skirt portion 9a suddenly causes a large bending to reduce the operation load, and the sudden decrease in the operation load gives a click feeling as a kind of moderation to the operation feeling. The click characteristics of the skirt portion 9a alone are shown by broken lines in FIG. 8 and FIG. 9 (the vertical axis is the operating force [g]).

The solid curve in FIG. 8 (the vertical axis represents the pressure [g /
cm ² ]) is a constant speed v [m
m / sec.], and shows the relationship between the displacement [mm] of the key top 11 and the pressure [g / cm ² ] generated in the air chamber 12 when the key input operation is performed by depressing at the speed of m / sec. With 3 as the parameter
The measurement was carried out while changing the steps (0.25, 0.5, 0.75 [mm]). The operation speed of the key input, the design value of the key stroke, and the volume of the air chamber 12 (per one key portion) in this measurement were as follows.・ Key input operation speed: v = 1.0 [mm / sec.] ・ Key stroke (design value): 1.5 [mm] ・ Air chamber volume (per key): 150 mm ³

As can be clearly understood from the graph of FIG.
When the orifice diameter d is in the above set range (0.42 to 0.75 [m
m]) and is too small (d = 0.25 [mm]), the operating load (pressure in the air chamber 12) at which a click feeling can be obtained is an upper limit value (30 [mm]) for damage due to the internal pressure of the diaphragm 8a. g / cm ² ])
It turns out to be unsuitable. On the other hand, for the other two cases in which the orifice diameter d is within the above-mentioned set range, the pressure in the air chamber 12 does not exceed the above-mentioned upper limit (30 [g / cm ² ]) and the electric contacts are closed. The pressure (5 [g / cm ² ]) required for the switch operation to be achieved is sufficiently higher. In addition, when a click feeling occurs due to the buckling phenomenon of the skirt portion 9a, the deformation of the skirt portion 9a occurs rapidly. Therefore, even if the pressing operation is performed at a constant speed, the pressure rapidly increases upon clicking. become.

The solid line curve in FIG. 9 (the vertical axis indicates pressure [g / cm ² ]) indicates that the center of the key top 11 has a constant velocity v [m] when the orifice diameter d is 0.5 [mm].
m / sec.] and shows the relationship between the displacement [mm] of the key top 11 and the pressure [g / cm ² ] generated in the air chamber 12 when the key input operation is performed by pressing down the key input operation. Using the operation speed v as a parameter, this is performed in three stages (0.5, 1.0, 1.5 [mm / sec.])
Was measured after changing. The keystroke design value and the air chamber 1
The volume of 2 (per one key part) was the same as the case of the measurement of FIG. As can be clearly understood from the graph of FIG. 9, when the orifice diameter d is 0.5 [mm], even if the operation speed v of the key input changes within the range of the standard input operation, the inside of the air chamber 12 is not changed. Occurs between the upper limit (30 g / cm ² ) and the lower limit (5 g / c).
m ² ]), satisfying the pressure condition.

As described above, the orifice diameter d is optimized based on the upper and lower limits of the operation speed in key input, the limit pressure in terms of the strength of the diaphragm 8a, and the operating pressure of the diaphragm 8a, and d = 0.42 to 0.75. Since the setting is made within the range of [mm], the key input operation is stabilized, the operation feeling is good, and there is no fear of breakage due to the internal pressure of the diaphragm 8a.

The skirt portion 9a of the peripheral wall of the air chamber 12 which falls from the key top 11 is formed of a predetermined elastic material (silicon rubber), and the shape of the skirt portion 9a (inclination with respect to the upper surface of the lower rubber sheet 8). The angle β) and the thickness Ts are set such that buckling deformation occurs when a keystroke reaches a certain value due to a pressing operation force of a predetermined value or more acting on the key top 11, so that key input is performed. By giving the operation a click feeling as a kind of moderation, a good operation feeling can be secured. In this case, since the skirt portion 9a is formed by using the peripheral wall of the air chamber 12, a component for generating a click feeling (for example, a click rubber) is separately arranged below the key top 11 as in the related art. The key input device 3 does not need to be provided, has a simple configuration, and does not affect the thickness of the key input device 3.

Further, the computer 1 according to the present embodiment
Since the key input device 3 configured as described above is incorporated, it is possible to improve operability, achieve further reduction in thickness, and improve portability. It should be noted that the present invention is not limited to the embodiments described above, and it is needless to say that various improvements or design changes can be made without departing from the gist of the present invention.

[0032]

As described above, according to the first aspect of the present invention, by depressing the keytop, the pressure in the fluid reservoir provided below the keytop increases, and the diaphragm is moved. Swell. Then, the movable electrode is pressed against the fixed electrode via the diaphragm, and the electric contact is closed. Therefore, unlike the related art, there is no need to dispose a contact pressing member, a guide mechanism, a pantograph mechanism, or the like between the keytop and the electric contact, and it is sufficient to provide the above-mentioned fluid storage part for storing a predetermined fluid. In addition, the thickness of the key input device can be significantly reduced as compared with the related art. Also, at the time of key input operation, even if the operation force acts on a portion deviated from the center of the key top or acts obliquely, a pressure rise occurs almost in the same way in the fluid reservoir, and the diaphragm expands. Thus, the key input operation can be performed more easily and reliably. That is, it is possible to maintain the certainty of the switch operation with respect to variations in the operation position or direction of the operation force.

Further, according to the invention of claim 2 of the present application, basically, the same effects as those of the invention of claim 1 can be obtained. In addition, the skirt portion is formed of a predetermined elastic material, and the shape and thickness of the skirt portion are such that buckling deformation occurs when a pressing operation force of a predetermined value or more acts on the key top. Since the key input operation is set, a click feeling as a kind of moderation is given to the key input operation, and it is possible to secure a good operation feeling. In this case, since the skirt portion is formed using the peripheral wall of the fluid storage portion, a component for generating a click feeling (for example, a click rubber) is separately provided below the keytop as in the related art. The key input device is not affected, and the configuration is simple.

Further, according to the invention of claim 3 of the present application, basically the same effects as those of the invention of claim 1 or 2 can be obtained. In addition, since an orifice having a predetermined throttle characteristic is provided on the peripheral wall of the fluid reservoir, by appropriately setting the throttle characteristic of the orifice, a key-top operation can be performed during key input operation. Accordingly, it is possible to appropriately adjust the rise in the pressure in the fluid storage unit, and it is possible to further improve the operation feeling. In addition, since the pressure in the fluid storage section can be prevented from excessively increasing, damage to the diaphragm can be prevented.

Further, according to the invention of claim 4 of the present application, basically, the same effect as the invention of claim 3 can be obtained. In particular, for a plurality of keys, the respective reservoirs communicate with each other via the orifice, so that when an operating force is applied to one keytop, the fluid in the fluid reservoir is used for another key. It can move to a fluid reservoir. Therefore, it is possible to prevent the pressure in the fluid storage unit from unnecessarily increasing with a simple configuration, to obtain a good stroke feeling, and to reliably prevent the diaphragm from being damaged.

Further, according to the invention of claim 5 of the present application, basically the same effects as those of the invention of claim 3 or 4 can be obtained. In addition, the orifice diameter d is optimized from the upper and lower limits of the operation speed in key input, the limit pressure in terms of diaphragm strength, and the operating pressure of the diaphragm, and d = 0.42 to 0.75 [m
m], the key input operation becomes stable, the operation feeling is good, and there is no fear of damage due to the internal pressure of the diaphragm. In addition, since the fluid stored in the fluid storage unit is air (air), it is easier to handle as compared with a case where other fluids such as oil are used, and there is no need to make the fluid system a closed system, and excess fluid is used. (Air) can be released to the atmosphere as it is.

According to the invention of claim 6 of the present application, a key input device incorporated in a computer can provide the same effects as those of the first to fifth inventions. It is possible to improve the operability and achieve a further reduction in thickness to obtain a more portable computer.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a computer according to an embodiment of the present invention.

FIG. 2 is an explanatory longitudinal sectional view of a key portion of the key input device of the computer according to the embodiment.

FIG. 3 is an explanatory longitudinal sectional view of a key portion showing a key input state.

FIG. 4 is an explanatory longitudinal sectional view of a key portion showing a single-pressed state.

FIG. 5 is an explanatory longitudinal sectional view of two key portions adjacent to each other.

FIG. 6 is an explanatory plan view of a part of the key input device.

FIG. 7 is a graph showing a relationship between an orifice diameter and a maximum pressure generated in an air chamber using a key input operation speed as a parameter.

FIG. 8 is a graph showing a relationship between a key top displacement and a pressure in an air chamber using an orifice diameter as a parameter.

FIG. 9 is a graph showing a relationship between a key top displacement and a pressure in an air chamber using a key input operation speed as a parameter.

[Explanation of symbols]

1 computer, 3 key input device, 7c movable electrode, 7d fixed electrode, 8a diaphragm, 9a skirt, 11 key top, 12 air chamber, 1
3 Orifice, d Orifice inner diameter, F key input operation force.

Claims (6)

[Claims] A key top for inputting a key by a pressing operation; and an electrical contact formed by a fixed electrode and a movable electrode. The movable electrode is pressed against the fixed electrode by the pressing operation of the key top. A key input device configured to close the contact points, wherein a fluid storage portion for storing a predetermined fluid is provided below the keytop, and a part of a peripheral wall of the fluid storage portion is configured to have a pressure inside the fluid storage portion. A key input device formed of a diaphragm that expands as it rises, wherein the movable electrode is pressed against the fixed electrode via the diaphragm by depressing the key top. 2. A skirt portion falling from at least the key top side of the peripheral wall of the fluid storage portion is formed of a predetermined elastic material, and the shape and thickness of the skirt portion are
2. The key input device according to claim 1, wherein a buckling deformation occurs when a pressing operation force equal to or more than a predetermined value acts on the key top. 3. The key input device according to claim 1, wherein an orifice having a predetermined throttle characteristic is provided on a peripheral wall of the fluid reservoir. 4. The key input device according to claim 3, wherein the storage portions of the plurality of keys communicate with each other via the orifice. 5. The fluid stored in the storage section is air, and the inner diameter d (mm) of the orifice is 0.42.
The key input device according to claim 3, wherein the key input device is set so as to satisfy ≦ d ≦ 0.75. 6. A computer comprising the key input device according to any one of claims 1 to 6.