JPH11152U - Key switch - Google Patents

Abstract

(57) [Summary] (with correction) [PROBLEMS] To provide a key mizutsu value capable of performing a reliable switching operation while always properly maintaining an arrangement relationship between a key top or a guide means and a rubber spring. A mounting hole is drilled in a holder member over an area defined by a pair of rotation locking portions and a pair of sliding locking portions, and a mounting hole is formed below the holder member. The switching parts 29, 29 of the arranged printed circuit board are arranged substantially in the center of the mounting hole 7a, and the movable contact part 30 of the rubber spring 6 arranged in the mounting hole 7a is separated from the switching parts 29, 29. The pressing force generated when the keytop is pressed is reduced by placing the halfway crossing portion of the first link and the second link at substantially the center of the upper surface of the rubber spring 6 so as to oppose each other. On the center of the upper surface of

Description

[Detailed description of the invention]

[0001]

[Industrial applications]

 The present invention relates to a key switch used for a keyboard of an input device such as a word processor and a personal computer.

[0002]

[Prior art]

 2. Description of the Related Art Conventionally, as a key switch in this kind of keyboard, there are key switches described in Japanese Utility Model Laid-Open No. 2-5236, Japanese Patent Laid-Open No. 60-62017, and the like.

[0003] Here, Japanese Utility Model Laid-Open No. 2-5236 describes a push button switch having an X-frame body which supports an outer rectangular frame and an inner rectangular frame so as to be rotatable in an X-shape. In this push-button switch, the upper part of the outer rectangular frame is rotatably supported between the back surface of the key top and the groove of the upper holder, and the legs are attached to the printed circuit board. It is slidably supported by the second lower holder of the mold, and the upper part of the inner rectangular frame is slidably supported between the back of the keytop and the flat part of the upper holder, and the legs are printed. A rubber switch that is rotatably supported by a first lower holder having a U-shaped cross section attached to the substrate and that performs switching between the keytop and the printed circuit board is provided.

Here, the rubber switch is disposed between the first lower holder and the second lower holder attached to the printed circuit board such that the movable contact of the rubber switch faces the fixed contact of the printed circuit board. . At this time, the rubber switch is not positioned and arranged on the printed circuit board, but is positioned and arranged with respect to the key top by mounting the lower end of the projection formed on the key top in the hole of the rubber switch. Have been.

Japanese Patent Application Laid-Open No. 60-60217 discloses that when one end of a key top, such as a space key, which has a larger planar shape than a contact portion, is pressed, the key top is not tilted but parallel. In order to move up and down, halfway portions of a pair of link members arranged in an X shape in side view are rotatably connected to each other, and the pair of link members are connected between the lower surface of the keytop and the holder member. Are described.

Here, the non-movable key portion attached to the substrate is provided with four guide pockets for locking the lower end of each link member, and an area defined by each guide pocket. A hole is formed in the substrate at an outer position deviating from the hole, and a switch body is disposed in the hole. A switch tappet formed on a carrier attached to the lower surface of the key top is opposed to such a switch body via a hole in a non-movable key portion.

[0007]

[Problems to be solved by the invention]

 By the way, in the push-button switch described in Japanese Utility Model Laid-Open No. 2-5236, no arrangement portion for positioning and arranging the rubber switch on the printed circuit board is formed, and the lower end of the projection of the key top is made of rubber. By mounting the rubber switch in the hole of the switch, the positioning and fixing of the rubber switch with respect to the key top are performed, and the positional relationship between the X frame and the printed circuit board is determined. In such a case, it is possible to perform the switching operation by applying the pressing force based on the pressing operation of the key top to the substantially central portion of the rubber switch, but it is necessary to attach the projection of the key top to the hole of the rubber switch. Is a complicated operation, and the assembling operation of the push button switch is naturally complicated. Also, the rubber switch is positioned only between the key top and the rubber switch and the printed circuit board. The positional relationship between the rubber switch and the printed circuit board is extremely relative. The fixed contacts are not always arranged in an appropriate relationship, and in some cases, when the keytop is pressed, the movable contacts and the fixed contacts may not be able to perform proper switching operation. .

On the other hand, the pressing key described in Japanese Patent Application Laid-Open No. 60-60217 has a configuration in which a hole is formed in a substrate and a switch body is disposed in the hole. By simply arranging the switch body in the hole of the board, the arrangement relation between the switch body and the switch portion of the switch foil 8 arranged below the board can be maintained in a fixed relation. It is possible to solve the problem as in the push button switch of No. 5236.

However, in the pressing key disclosed in Japanese Patent Application Laid-Open No. 60-60217, the hole of the board on which the switch body is disposed is defined by four guide pockets that lock the lower ends of the pair of link members. It is formed at an outer position outside the region where the key top is located, and is located far away from the central portion of the key top and the rotation support portion of each link member. Moreover, the switch tappet of the carrier and the hole of the non-movable key portion are set in a rather loose insertion relationship with a gap between the two, as is apparent from the drawing.

In the pressing key, the key top is guided to move up and down via each link member when pressed, but is pressed at a position separated from the center of the key top and the rotation support portion of each link member. In this case, the hole of the substrate is formed at an outer position outside the area defined by the four guide pockets as described above, and the switch tappet and the hole of the non-movable key portion are loose. There is a possibility that the key top may move in the horizontal direction due to the setting of the insertion relationship. In such a case, the positional relationship between the lower end of the switch tappet and the upper surface of the switch body is displaced, so that the pressing force based on the pressing operation of the keytop does not properly act on the switch body. As a result, the switch body cannot perform the original elastic deformation, and in some cases, the switching operation of the switch foil cannot be performed properly.

The present invention has been made to solve the above-mentioned conventional problems, and has four locking portions for movably locking a pin formed at a lower free end of each of a pair of links. In addition, a spring arrangement hole for disposing a rubber spring is formed in the holder member at a substantially central portion of a region defined by each locking portion, and a pressing force based on an input operation of the keytop is applied to a substantially central portion of the upper surface of the rubber spring. It is an object of the present invention to provide a key switch capable of performing a reliable switching operation while always properly maintaining an arrangement relation between a key top or a means and a rubber spring by acting.

[0012]

[Means for Solving the Problems]

 In order to achieve the above object, the key switch according to claim 1 of the present invention is provided with a guide means for connecting and locking to a lower surface of the key top and a holder member thereunder to guide and support the vertical movement of the key top; A cap-shaped rubber spring that can be elastically deformed by an input operation using the key top; and a switch unit that performs a switching operation by elastic deformation of the rubber spring. The guide unit includes a first link and a second link. And a key switch in which the free ends of the first link and the second link are connected and locked to the lower surface of the key top and the holder member, respectively. A pair of first pins formed at the ends, a pair of second pins formed at the lower free end of the second link, and a first pin of the first link formed at the holder member. Four locking portions for movably locking the second pins of the two links, and a holder member formed at a substantially central portion of a region defined by the locking portions, for input operation of the key top. And a spring arrangement hole for disposing the rubber spring so that the applied pressing force acts on a substantially central portion of the upper surface of the rubber spring.

According to a second aspect of the present invention, there is provided a key switch according to the first aspect, wherein the first link and the second link are arranged so as to cross each other in an X shape in a side view. Is characterized in that the key is pressed through an intersecting portion of the first link and the second link during an input operation of the key top.

[0014]

【Example】

 Next, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a side sectional view of a key switch. The key switch 1 has a key top 2, a guide means 3 in which a first link 4 and a second link 5 are arranged in an X-shape in a side view, and the guide means 3. A rubber spring 6 in the form of a cap pressed by the above, a holder member 7 made of synthetic resin for supporting the guide means 3, and a mounting portion 7a of the holder member 7 for positioning and positioning the rubber spring are provided in the switching portion 29, It comprises a flexible printed circuit board 9 stretched on the lower surface of the holder member 7 so as to face 29 (see FIGS. 7 and 8), and a reinforcing plate 10 stretched on the lower surface side.

As shown in FIGS. 1, 2 and 7, the rubber spring 6 is provided with a mounting hole for the holder member 7 so as to cover above the switching portions (electric contact portions) 29, 29 on the printed circuit board 9. 7a. The rubber spring 6 of the present invention is made of an electrically insulating silicone rubber or EPDM (ethylene propylene diene methylene) or the like, and has a substantially disk-shaped thick head in plan view and a cutout extending downward from the periphery of the head. It is integrally formed into a downward-opening cap having a conical domed dome portion and a thick-walled flange portion extending substantially horizontally and radially outward on the outer periphery of the dome portion. When the key top is depressed, the lower surface of the head of the rubber spring 6 pressed by the lower surface of the connection intersection between the first link 4 and the second link 5 comes into contact with the contact portions of the switching portions 29, 29. A movable contact portion 30 made of conductive rubber having conductivity for electrically turning on and off both switching portions is fixed. The entire rubber spring 6 may be formed to have conductivity by dispersing and filling conductive particles such as carbon black in silicone rubber.

The key top 2 formed of a synthetic resin such as an ABS resin has characters such as numerals, alphabets, etc. stamped or printed on the upper surface (surface) thereof. On the lower surface of the key top 2, a longitudinal groove for locking the pin portions 11a and 11b on the upper free end side of the first link 4 to be described later in a substantially horizontal direction so as to be slidable in the longitudinal direction of the key top 2. Sliding locking portions 16, 16 and hole-shaped rotating locking portions 15, 15 for locking the pin portions 13 a, 13 b at the upper free end of the second link 5 so as to be rotatable only. A pair of left and right locking members 17, 17 having front and rear lengths integrally formed with each other are integrally formed or bonded to each other with an adhesive or the like to project (see FIG. 5).

The first link 4 and the second link 5 made of a synthetic resin such as a glass fiber reinforced synthetic resin will be described in detail with reference to FIGS. FIG. 4A is a plan view of the first link 4, and FIG. 4B is a plan view of the second link 5. The first link 4 is formed integrally with the base 18 and the upper and lower free ends 19 and 20 in a substantially H-shape in plan view, and the base 18 has a support hole 21 penetrating in a horizontal direction on a side surface thereof. Prepare. Pin portions 12a and 12b are laterally protruded from side surfaces of the arm portions 20a and 20b extending from both left and right ends of the lower free end portion 20, and pin portions 11a and 11b are laterally protruded from the side surface of the upper free end portion 19. To protrude.

Further, the second link 5 is also substantially integrally formed in a substantially H shape in plan view by the base 22 and the upper and lower free ends 23 and 24. A support shaft 25 projects laterally from one side surface of the base 22, and the support shaft 25 is inserted into the support hole 21 of the first link 4, and the first link 4 and the second link 5 are connected to the support shaft 25. It is connected so as to be able to rotate around 25. Pins 14a, 14b are provided on the side surfaces of the arms 24a, 24b extending from both left and right ends of the lower free end 24 of the second link 5, respectively. The connecting parts 13a and 13b are provided to project sideways.

In this embodiment, the distance from the center line of the support hole 21 in the first link 4 to the center line of the upper and lower pin portions 11 a and 12 a and the support shaft 25 in the second link 5 are viewed from the side. The pins are formed so that the distances from the center line to the pin portions 13a and 14a are equal to each other. With this configuration, as described later, the key means 2 is displaced around the pin portions 12a and 12b on the lower free end side of the first link 4 so that the key top 2 is moved to the position of the holder member 7. It can move up and down in parallel to the upper surface.

FIGS. 7 and 8 are views showing a part of the holder member 7 made of a synthetic resin such as glass fiber reinforced synthetic resin (preferably separate from the two links 4 and 5). A substantially rectangular mounting hole 7a is formed in the material 7 so that the flange at the lower end of the cap-shaped rubber spring 6 can be inserted without displacement. A pair of left and right mounting holes are formed in the left and right side edges of the mounting hole 7a. The rotation locking part 27 and the sliding locking part 28 in the shape of a longitudinal groove are integrally formed by injection so that the locking parts 27 and 28 are opened downward. The lower end side pin portions 12a, 12b of the first link 4 are rotatably fitted into the rotation locking portions 27, 27, and the pin portions 12a, 12b are The pin portions 14a and 14b on the lower end side of the two links 5 are inserted so as to slide back and forth.

As shown in FIG. 8, the mounting hole 7 a is formed in the holder member 7 over an area defined by the pair of rotation locking portions 27 and the pair of sliding locking portions 28. The switching portions 29, 29 of the printed circuit board 9 which are formed and disposed below the holder member 7 are disposed substantially at the center of the mounting hole 7a. Thus, the movable contact portion 30 of the rubber spring 6 disposed in the mounting hole 7a and the switching portions 29, 29 are opposed to each other while being separated from each other, and the intermediate intersection of the first link 4 and the second link 5 is a rubber spring. 1 and 2, the pressing force generated when the key top 2 is depressed moves from the halfway intersection to the substantially central portion of the upper surface of the rubber spring 6. Works. As a result, a reliable switching operation can be performed via the movable contact portion 30 and the switching portions 29, 29 while always properly maintaining the arrangement relationship between the key top 2, the guide means 3, and the rubber spring 6.

At this time, the shape and dimensions of the pin portions 11a, 11b and 14a, 14b and the sliding locking portions 16, 28 are such that the first link 4 and the second link 5 are substantially immovable in the left-right direction in FIG. In addition, it is determined so as not to hinder the sliding of the pin portions 11a and 14a in the left-right direction in FIG. Specifically, in the present embodiment, the tip of each pin portion slides while substantially in contact with the outer side surface of the corresponding sliding engagement portion. This also prevents the support shaft 25 from coming out of the support hole 21.

With this configuration, when the key top 2 is pressed, the first link 4 rotates downward about the rotation locking portion 27 of the holder member 7, so that the first link 4 and the second link are rotated. The halfway crossing portion, which is pivotally connected in an X-shape with the side view 5, presses the head of the rubber spring 6 obliquely downward.

In a state where the key top 2 is not pressed downward (free state), the elastic force of the rubber spring 6 causes the lower end side of the second link 5 when the key top 2 is at the highest position. The pin portions 14a and 14b are configured to abut against the front stopper portion 31 on one side surface (the side surface closer to the rotation locking portion 27) of the sliding locking portions 28 and 28. In this case, by changing the horizontal distance (L1) from the rotation locking portion 27 to the front stopper portion 31, the height dimension (H1) from the upper surface of the holder member 7 when the keytop 2 is at the highest position. Can be regulated. By changing the longitudinal length (L2) of the long groove of the sliding engagement portion 28, the vertical movement distance (H2) of the guide means 3 itself can be regulated.

The distance from the highest position of the key top 2 to the maximum pressing of the rubber spring 6 by the guide means 3 until the rubber spring 6 is pressed downward (referred to as a push-off state) is called a stroke. Before the push-off state (at a higher position), the lower end side pin portions 14a, 14b of the second link 5 are connected to the other side surfaces of the sliding locking portions 28, 28 (side surfaces farther from the rotation locking portion 27). By contacting the rear stopper 32, the lowermost position of the key top 2 can be substantially regulated. As a result, even if the length of the sliding groove is the same, the highest position of the key top 2 and the substantial stroke can be changed simultaneously only by changing the position of the front stopper portion 31. It is possible to provide a key having a short troke and a low highest position of the key top.

As described above, the distance (L 1) from the rotation locking portion 27 of the holder member 7 to the front stopper portion 31 of the sliding locking portion 28 can be changed. By changing the distance (L2) between the front stopper portion 31 and the rear stopper portion 32, in other words, by changing the length of the sliding groove, the distance from the support shaft 25 of the two links 4 and 5 of the guide means 3 to the pin portion is changed. The maximum position and the stroke of the key top 2 can be arbitrarily changed without changing the dimensions of the key top 2 and the vertical dimension of the rubber spring.

In order to change the distances (L1) and (L2), the position of the sliding locking portion 28 and / or the groove length of the sliding groove portion in one of the injection molding dies of the holder member 7 is changed. May be changed, or after the slide locking portion 28 is formed to have a relatively large thickness by injection molding, the sliding groove of the sliding locking portion 28 where the stroke is to be changed is cut. By doing so, the front stopper 31 and / or the rear stopper 32 may be adjusted so as to be determined.

Therefore, in the present embodiment, in a single keyboard, the stroke amount is increased for a key for outputting a character code, a line feed code, and the like, and a half key (generally, a half key) Keys (used as function keys) are reduced in stroke volume. In this way, these key touches are changed, and when the user uses a blind touch, the difference between the keys can be confirmed without visual inspection, thereby improving the use efficiency.

At this time, since the holder members 7 of all the keys are integrally formed into a single plate, even if there are two types of positions of the stopper portions 31 and 32 formed on the holder member 7, Its manufacturing cost is not different from the conventional one. In addition, since the first link 4 and the second link 5 use the same key even if the keys have different strokes, the first link 4 and the second link 5 are different from the conventional one in which the shape of the guide means is changed according to the stroke amount. Manufacturing costs can be greatly reduced.

In order to regulate the highest position of the key top 2 and to adjust the stroke size, the shape of the pair of locking members 17 provided on the lower surface of the key top 2 instead of the holder member 7 is changed. Is also good. That is, one stopper portion (rotation) of the sliding locking portions 16, 16 for locking the pin portions 11a, 11b on the upper free end side of the first link 4 so as to be slidable in the front-rear direction in a substantially horizontal direction. The position on the side closer to the locking portion 15) and / or the length of the sliding groove of the sliding locking portion 16 may be changed. Further, the rotation locking portion 15 and the sliding locking portion 16 may be separately provided on the lower surface of the key top 2.

As described above, before the rubber spring 6 is pushed and cut off, the position of the sliding engagement portion 28 is adjusted so that the lower end side pin portions 14 a and 14 b of the second link 5 abut the rear stopper portion 32. When the sliding length is set, it is possible to prevent the rubber spring 6 from being pressed to the utmost limit, so that an excessive force does not act on the rubber spring 6 and the rubber spring 6 can be protected. Further, just before the push-off state, the pin portions of the first link 4 and / or the second link 5 in the guide means 3 abut against the rear stopper portions 32 of the sliding engagement portions 16 and 28, thereby further increasing the distance. By utilizing the fact that the first link 4 and the second link 5 elastically bend when the key top 2 is pressed, it is possible to reduce the impact of the key touch up to the full press.

Further, in this embodiment, an example in which two types of strokes are provided on a single keyboard has been described. However, for example, a keyboard which is required to be thinner than key strokes of a portable computer or the like is required. It is also possible to compose a keyboard such as a stationary type that requires a larger keystroke with the same guide means. Even in this case, since the guide means conventionally manufactured as a separate part can be made common, the total manufacturing cost is greatly reduced. It should be noted that a substrate such as a membrane switch circuit board may be used instead of the flexible printed board 9 forming the switching section 29, and the present invention is also applicable to a variable capacity keyboard.

[Functions and effects of the invention]

 In short, in the present invention, in the present invention, four locking portions movably locking the pins formed at the lower free ends of each pair of links, and approximately the center of the area defined by each locking portion. A spring arrangement hole for placing the rubber spring is formed in the holder member, and the pressing force based on the input operation of the key top is applied to approximately the center of the upper surface of the rubber spring, so that the arrangement relation between the key top and the guide means and the rubber spring is adjusted. Can be surely performed while always properly maintaining the switching operation.

In particular, the first link and the second link constituting the guide means are arranged to cross each other in an X-shape when viewed from the side, and the rubber springs are connected to the first link and the second link at the time of key top input operation. Is pressed through the midway crossing part, and the pressing force based on the input operation of the key top is applied directly from the midway crossing part of the first link and the second link to the approximate center of the upper surface of the rubber spring. Enables reliable switching operation.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a key switch.

FIG. 2 is a side sectional view of the key switch when a position of a stopper portion is changed.

FIG. 3 is a side sectional view in a case where a key switch is pushed down to a full cut-off state;

4A is a plan view of a first link, and FIG. 4B is a plan view of a second link.

FIG. 5 is a bottom view of the key top.

FIG. 6 is a sectional view taken along the line VI-VI in FIG. 1;

FIG. 7 is a plan view of a rubber spring and a mounting hole.

FIG. 8 is a perspective view of a mounting hole of a holder member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Key switch 2 Key top 3 Guide means 4 1st link 5 2nd link 6 Rubber spring 7 Holder member 7a Mounting hole 9 Printed circuit board 10 Reinforcement board 11a, 11b, 12a, 12b Pin part 15, 27 Rotation locking part 16 , 28 Sliding locking part 25 Support shaft 29 Switching part 30 Movable contact part 31 Front stopper part 32 Rear stopper part

Continued on the front page (72) Inventor Isao Mochizuki Brother Industrial Co., Ltd. 15-1, Nashiro-cho, Mizuho-ku, Nagoya

Claims (2)

[Utility model registration claims] 1. A guide means for connecting and locking to a lower surface of a key top and a holder member therebelow to guide and support the vertical movement of the key top, and a cap which can be elastically deformed by an input operation by the key top. A rubber spring, and a switch part that performs a switching operation by elastic deformation of the rubber spring. The guide means comprises a first link and a second link movably connected to each other. In a key switch in which each free end of a link and a second link is connected and locked to a lower surface of the key top and a holder member, a pair of first pins formed at a lower free end of the first link; A pair of second pins formed at a lower free end of the first link, and four engaging members formed on the holder member for movably locking each first pin of the first link and each second pin of the second link. A rubber member such that a pressing force based on an input operation of the key top acts on a substantially central portion of the upper surface of the rubber spring. A key switch comprising a spring arrangement hole for disposing a spring. 2. The first link and the second link are arranged so as to cross each other in an X-shape when viewed from the side, and the rubber spring is provided at an intermediate crossing portion between the first link and the second link when a keytop is operated. The key switch according to claim 1, wherein the key switch is pressed through the key switch.