US 2001/0011999 A1Published application

Key switch device, keyboard with the key switch device, and electronic apparatus with the keyboard

AssigneeBrother Kogyo Kabushiki Kaisha

InventorIsao Mochizuki

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Abstract

In a key switch device, the depressing load applied to a key top 11 when depressed is defined by a function (equation 26) expressed by: a distance L between the rotation point o of a support shaft 30 of a first link member 12 at a first engagement portion 17 in the key top 11 and the slide starting point s of a support shaft 26 of the first link member 12 at a third engagement portion 40; a distance L1 between the rotation point o and the acting point m at which the urging force of the coil spring 15 acts on the first link member 12; an angle θ4 between a line segment extending from the rotation point o to the slide starting point s and the direction along which the support shaft 26 of the first link member 12 at the third engagement portion 40 is allowed to slide; and various characteristic values of the coil spring 15. In relation to the depressing load curve P defined by the function, based on the difference in loads between the maximum point P1 in an upward projecting curve and the minimum point P2 from which the depressing load is increased after the switching operation, the key clicking function is performed.

Claims37

Dependent claims

A key switch device including:

a key top provided at its underside with a first engagement portion and a second engagement portion;
a third engagement portion corresponding to the first engagement portion, and a fourth engagement portion corresponding to the second engagement portion, both of which are arranged below the key top;
a first link member provided with an upper end portion which is rotatably engaged in the first engagement portion and a lower end portion which is slidably engaged in the third engagement portion;
a second link member provided with an upper end portion which is rotatably engaged in the second engagement portion and a lower end portion which is slidably engaged in the fourth engagement portion;
an urging member for urging the first link member and the second link member in a direction to allow them to come close to each other;
and
a switching member for conducting a switching operation in association with vertical movement of the key top,
the key switch device being designed to be symmetric with respect to a perpendicular line passing through a midpoint between the first engagement portion and the second engagement portion,
wherein the upper end portion of the first link member is allowed to rotate about a predetermined rotation point in the first engagement portion, and the lower end portion of the first link member is allowed to slide outwardly from a predetermined slide starting point in the third engagement portion,
an urging force of the urging member is exerted on the first link member at a predetermined acting point in the first link member,
a depressing load applied to the key top when the key top is depressed is defined by a function expressed by:
a distance between the rotation point and the slide starting point;
a distance between the rotation point and the acting point;
an angle between a line segment extending from the rotation point to the slide starting point, and the direction along which the lower end portion of the first link member in the third engagement portion is allowed to slide;
and various characteristic values of the urging member;
and
a curve of the depressing load defined by the function takes a shape of an upward projecting curve having a maximum point, and a key clicking function is performed based on a difference in loads between the maximum point and a point from which the depressing load starts to increase after the switching operation is conducted by the switching member.

14 more elements

An electronic apparatus including:

a keyboard for inputting various data such as characters, symbols, and others, the keyboard being provided with a key switch device including:
a key top provided at its underside with a first engagement portion and a second engagement portion;
a third engagement portion corresponding to the first engagement portion, and a fourth engagement portion corresponding to the second engagement portion, both of which are arranged below the key top;
a first link member provided with an upper end portion which is rotatably engaged in the first engagement portion and a lower end portion which is slidably engaged in the third engagement portion;
a second link member provided with an upper end portion which is rotatably engaged in the second engagement portion and a lower end portion which is slidably engaged in the fourth engagement portion;
an urging member for urging the first link member and the second link member in a direction to allow them to come close to each other;
and
a switching member for conducting a switching operation in association with vertical movement of the key top,
the key switch device being designed to be symmetric with respect to a perpendicular line passing through a midpoint between the first engagement portion and the second engagement portion,
wherein the upper end portion of the first link member is allowed to rotate about a predetermined rotation point in the first engagement portion, and the lower end portion of the first link member is allowed to slide outwardly from a predetermined slide starting point in the third engagement portion,
an urging force of the urging member is exerted on the first link member at a predetermined acting point in the first link member,
a depressing load applied to the key top when the key top is depressed is defined by a function expressed by:
a distance between the rotation point and the slide starting point;
a distance between the rotation point and the acting point;
an angle between a line segment extending from the rotation point to the slide starting point, and the direction along which the lower end portion of the first link member in the third engagement portion is allowed to slide;
and various characteristic values of the urging member;
and
a curve of the depressing load defined by the function takes a shape of an upward projecting curve having a maximum point, and a key clicking function is performed based on a difference in loads between the maximum point and a point from which the depressing load starts to increase after the switching operation is conducted by the switching member;
display means for displaying the characters, symbols, and others;
and
control means for controlling the display means to display the characters, symbols, and others based on input data from the keyboard.

18 more elements

A key switch device including:

a key top provided at its underside with a first engagement portion and a second engagement portion;
a third engagement portion corresponding to the first engagement portion, and a fourth engagement portion corresponding to the second engagement portion, both of which are arranged below the key top;
a first link member provided with an upper end portion which is rotatably engaged in the first engagement portion and a lower end portion which is slidably engaged in the third engagement portion;
a second link member provided with an upper end portion which is rotatably engaged in the second engagement portion and a lower end portion which is slidably engaged in the fourth engagement portion;
an urging member for urging the first link member and the second link member in a direction away from each other;
and
a switching member for conducting a switching operation in association with vertical movement of the key top,
the key switch device being designed to be symmetric with respect to a perpendicular line passing through a midpoint between the first engagement portion and the second engagement portion,
wherein the upper end portion of the first link member is allowed to rotate about a predetermined rotation point in the first engagement portion, and the lower end portion of the first link member is allowed to slide outwardly from a predetermined slide starting point in the third engagement portion,
an urging force of the urging member is exerted on the first link member at a predetermined acting point in the first link member,
a depressing load applied to the key top when the key top is depressed is defined by a function expressed by:
a distance between the rotation point and the slide starting point;
a distance between the rotation point and the acting point;
an angle between a line segment extending from the rotation point to the slide starting point, and the direction along which the lower end portion of the first link member in the third engagement portion is allowed to slide;
and various characteristic values of the urging member;
and
a curve of the depressing load defined by the function takes a shape of an upward projecting curve having a maximum point, and a key clicking function is performed based on a difference in loads between the maximum point and a point from which the depressing load starts to increase after the switching operation is conducted by the switching member.

14 more elements

An electronic apparatus including:

a keyboard for inputting various data such as characters, symbols, and others, the keyboard being provided with a key switch device including:
a key top provided at its underside with a first engagement portion and a second engagement portion;
a third engagement portion corresponding to the first engagement portion, and a fourth engagement portion corresponding to the second engagement portion, both of which are arranged below the key top;
a first link member provided with an upper end portion which is rotatably engaged in the first engagement portion and a lower end portion which is slidably engaged in the third engagement portion;
a second link member provided with an upper end portion which is rotatably engaged in the second engagement portion and a lower end portion which is slidably engaged in the fourth engagement portion;
an urging member for urging the first link member and the second link member in a direction away from each other;
and
a switching member for conducting a switching operation in association with vertical movement of the key top,
the key switch device being designed to be symmetric with respect to a perpendicular line passing through a midpoint between the first engagement portion and the second engagement portion,
wherein the upper end portion of the first link member is allowed to rotate about a predetermined rotation point in the first engagement portion, and the lower end portion of the first link member is allowed to slide outwardly from a predetermined slide starting point in the third engagement portion,
an urging force of the urging member is exerted on the first link member at a predetermined acting point in the first link member,
a depressing load applied to the key top when the key top is depressed is defined by a function expressed by:
a distance between the rotation point and the slide starting point;
a distance between the rotation point and the acting point;
an angle between a line segment extending from the rotation point to the slide starting point, and the direction along which the lower end portion of the first link member in the third engagement portion is allowed to slide;
and various characteristic values of the urging member;
and
a curve of the depressing load defined by the function takes a shape of an upward projecting curve having a maximum point, and a key clicking function is performed based on a difference in loads between the maximum point and a point from which the depressing load starts to increase after the switching operation is conducted by the switching member;
display means for displaying the characters, symbols, and others;
and
control means for controlling the display means to display the characters, symbols, and others based on input data from the keyboard.

18 more elements

A key switch device including:

a key top provided at its underside with a first engagement portion and a second engagement portion;
a third engagement portion corresponding to the first engagement portion, and a fourth engagement portion corresponding to the second engagement portion, both of which are arranged below the key top;
a guide member including:
a first link member provided with an upper end portion which is rotatably engaged in the second engagement portion and a lower end portion which is slidably engaged in the third engagement portion, and
a second link member provided with an upper end portion which is rotatably engaged in the first engagement portion and a lower end portion which is slidably engaged in the fourth engagement portion,
the first and second link members being pivotally supported to be rotatable with respect to each other;
an urging member for urging the first link member and the second link member in a direction to allow them to pivotally rotate about a shaft supporting point;
and
a switching member for conducting a switching operation in association with vertical movement of the key top,
the key switch device being designed to be symmetric with respect to a perpendicular line passing through a midpoint between the first engagement portion and the second engagement portion,
wherein the upper end portion of the first link member is allowed to rotate about a predetermined rotation point in the second engagement portion, and the lower end portion of the first link member is allowed to slide outwardly from a predetermined slide starting point in the third engagement portion,
an urging force of the urging member is exerted on the first link member at a predetermined acting point in the first link member,
a depressing load applied to the key top when the key top is depressed is defined by a function expressed by:
a distance between the rotation point and the slide starting point;
a distance between the rotation point and the acting point;
a distance between the rotation point and the shaft supporting point;
an angle between a line segment extending from the rotation point to the slide starting point, and the direction along which the lower end portion of the first link member in the third engagement portion is allowed to slide;
and various characteristic values of the urging member;
and
a curve of the depressing load defined by the function takes a shape of an upward projecting curve having a maximum point, and a key clicking function is performed based on a difference in loads between the maximum point and a point from which the depressing load starts to increase after the switching operation is conducted by the switching member.

17 more elements

An electronic apparatus including:

a keyboard for inputting various data such as characters, symbols, and others, the keyboard being provided with a key switch device including:
a key top provided at its underside with a first engagement portion and a second engagement portion;
a third engagement portion corresponding to the first engagement portion, and a fourth engagement portion corresponding to the second engagement portion, both of which are arranged below the key top;
a guide member including:
a first link member provided with an upper end portion which is rotatably engaged in the second engagement portion and a lower end portion which is slidably engaged in the third engagement portion, and
a second link member provided with an upper end portion which is rotatably engaged in the first engagement portion and a lower end portion which is slidably engaged in the fourth engagement portion,
the first and second link members being pivotally supported to be rotatable with respect to each other;
an urging member for urging the first link member and the second link member in a direction to allow them to pivotally rotate about a shaft supporting point;
and
a switching member for conducting a switching operation in association with vertical movement of the key top,
the key switch device being designed to be symmetric with respect to a perpendicular line passing through a midpoint between the first engagement portion and the second engagement portion,
wherein the upper end portion of the first link member is allowed to rotate about a predetermined rotation point in the second engagement portion, and the lower end portion of the first link member is allowed to slide outwardly from a predetermined slide starting point in the third engagement portion,
an urging force of the urging member is exerted on the first link member at a predetermined acting point in the first link member,
a depressing load applied to the key top when the key top is depressed is defined by a function expressed by:
a distance between the rotation point and the slide starting point;
a distance between the rotation point and the acting point;
a distance between the rotation point and the shaft supporting point;
an angle between a line segment extending from the rotation point to the slide starting point, and the direction along which the lower end portion of the first link member in the third engagement portion is allowed to slide;
and various characteristic values of the urging member;
and
a curve of the depressing load defined by the function takes a shape of an upward projecting curve having a maximum point, and a key clicking function is performed based on a difference in loads between the maximum point and a point from which the depressing load starts to increase after the switching operation is conducted by the switching member;
display means for displaying the characters, symbols, and others;
and
control means for controlling the display means to display the characters, symbols, and others based on input data from the keyboard.

21 more elements

Dependencies are inferred from the claim text.