JP3392809B2 - Key switch device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a key switch device, and more particularly to a key switch device suitable for use in a thin keyboard attached to a notebook word processor, a notebook personal computer or the like.

[0002]

2. Description of the Related Art Conventionally, a key switch device generally has a structure in which a circuit board made of an insulating film is sandwiched between a holder member and a switch support plate as described in the specification and drawings attached to Japanese Patent Application No. 3-330160. have.

On the film circuit board, there are printed two kinds of switching circuits and a fixed contact pattern in which fixed contacts extending from each circuit are combined in a comb-like shape, and at positions corresponding to the fixed contact patterns. Has a rubber spring formed in an inverted cup shape. The rubber spring has a movable contact inside, and a switching operation is performed by pressing the rubber spring.

An actuator is installed on the holder member corresponding to the rubber spring, and a key top is placed on the upper end of the actuator. When the operator presses the key top, the actuator receives the key top and guides the key top to the upper portion of the corresponding rubber spring, and presses the rubber spring. When the pressing amount exceeds a certain amount, the movable contact inside the rubber spring comes into contact with the fixed contact pattern, and the fixed contacts are short-circuited to perform switching.

The switch support plate corresponds to the lower cover of the keyboard device and enhances the rigidity of the keyboard device and the reliability of key input.

[0006]

However, with the recent trend toward smaller, thinner, lighter, and cheaper word processors, personal computers, and the like, keyboards attached to them have also been made smaller and thinner. There is.

On the other hand, it is required that the movable part of the key has excellent ergonomic operability (generally, the amount of down pressure required by a person is 3 to 4 mm). Therefore, it is necessary to satisfy the above-mentioned demand while ensuring this pushing stroke.

However, many parts around the key actuator and the holder member are mainly made of a resin material, and the processing method is mainly formed by injection molding. Therefore, a minimum thickness of 1.5 mm is required for each member. This means that it becomes more difficult to reduce the thickness as the number of parts to be stacked increases, and the weight naturally increases.

Further, the conventional key switch device has a three-layer structure of a holder member, a film circuit board, and a switch support plate. If these three layers are not aligned without any gap, the response of the key operation will be unreliable. For this reason, there are some types that are processed to suppress the floating of the three layers for each key or at regular intervals, but this process requires a considerable amount of time and labor.

The present invention has been made to solve the above-mentioned problems, and has a simple structure by integrating a board, an electric circuit pattern, and a locking portion for locking a link member. In addition, it is an object of the present invention to provide a key switch device that is compatible with downsizing and thinning of a keyboard, can secure a sufficient key stroke, has good operability of key input, and enables reliable key input. To do.

[0011]

In order to achieve this object, a key switch device of the present invention has a substrate formed of a plastically deformable metal material, and printed on the surface of the substrate. A fixed contact pattern, which has a circuit pattern and a fixed contact formed in the circuit pattern, is formed by printing on the front surface of the substrate, and is provided corresponding to the fixed contact pattern. A key top having a key top and a first locking portion of the key top, one end of which is locked, and a link member for guiding and supporting the key top in the vertical direction, and a vertical movement of the key top. A movable contact that performs a switching operation with the fixed contact, and a second locking portion that locks the other end of the link member is formed on the substrate.

Here, the second locking portion may be composed of a rotation locking portion and a sliding locking portion by press working from the back surface of the substrate.

[0013]

According to the key switch device of the present invention having the above structure, when the key top is pushed down, the link member connected to the first locking portion guides the key top downward. Further, when the key top is pressed, a switching operation is performed between the movable contact and the fixed contact pattern printed on the substrate.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will now be described in detail with reference to the drawings.

1 and 2 show a substrate 1 of a key switch device of this embodiment. The substrate 1 is made of a plastically deformable metal such as iron or aluminum, and its surface is subjected to resist printing as an insulating process. A first electric circuit pattern for switching is printed on the insulating surface with a conductive paint such as silver, and insulation printing is performed on a portion corresponding to the intersection of the second electric circuit pattern and the first circuit pattern. The second circuit pattern is then similarly printed with electrically conductive paint. Then, at fixed intervals, the fixed hand-shaped fixed contacts respectively extended from the two circuits are combined to form the fixed contact pattern 2.

[0016] Note that performs carbon coating on portion corresponding to the fixed contact pattern 2 and a connector (not shown), performs resist printed on the other circuit surface, thereby preventing deterioration due to oxidation of the printed circuit lines. Further, there is also one in which a protective film is stuck on the circuit surface for protection of the circuit surface during plastic working.

[0017] Around the fixed contact pattern 2, the mounting portion 1a of the guide support member, the mounting portion 1c is formed integrally with the substrate 1 by press working. Mounting part 1a, mounting part 1
c is formed so as to surround the fixed contact pattern 2 and to be arranged in a rectangular shape at four points on the upper, lower, left and right sides thereof. Mounting part 1a
Has a structure in which two locking shafts 8a of the guide support member 6 which will be described later are rotationally locked, and the mounting portion 1c is configured to horizontally lock the locking pin 7a.

That is, the mounting portion 1a is integrally formed in a convex shape from the substrate 1 and is machined into an arc shape so as to have a locking hole sufficient to rotate the locking shaft 8a. The mounting portion 1c that slides and locks is integrally formed in a convex shape from the substrate 1 and is processed into a U-shape when viewed in the horizontal direction so as to have a locking hole having a long hole shape.

In general, a large number of fixed contact patterns 2 are arranged regularly in the vertical and horizontal directions, and two types of mounting portions 1a, 1
The c's are also formed so that they are arranged in the same row.

By the way, the mounting portion 1a on the substrate 1 of embodying the key switch of the present invention, formation of the mounting portion 1c is performed as follows. First, at a predetermined site on the substrate 1,
By removing and cutting out the U-shaped blank 1b , the hinge part (the part that contacts the mounting part 1a or the mounting part 1c) remains.
And (referred to as the machining blanking below), then mounting portion 1 and the hinge portion by'll bending pressed
a, the mounting portion 1c is formed. However, in general, press working is often used for blanking a metal plate from the viewpoint of cost. Since blanking by pressing is a process in which a punch as a punching die shears and breaks through a die, when viewed from the surface on the pressing side, sagging occurs on the upper surface and burrs 11 occur on the back surface. The burr 11 is harmful to the smooth movement of the locking pin. When the blank processing is performed from the back surface, the burrs 11 that prevent the movement of the locking shaft 8a and the locking pin 7a are formed on the boundary line of the blank portion 1b on the front surface of the substrate 1.

[0021] In order to prevent damage of the burr, as shown in FIG. 8, a portion of the predetermined portion on the substrate 1, the mounting portions 1a, the engaging shaft 8a and the locking pin 7a at 1c near the touch, The thick film 3 is printed. Due to the presence of the thick film 3, the locking shaft 8a and the locking pin 7a are on the thick film 3 as shown in FIG. 9, and the guide support member 6 floats from the surface of the substrate 1 by that amount. Since the thickness of the thick film 3 is sufficiently thicker than the height of the burr 11, the locking shaft 8a and the locking pin 7a can move smoothly without being caught by the burr 11. In addition, the substrate 1 has a hole when the mounting portions 1a and 1c are formed, and this hole functions as a hole for cooling, thereby exhibiting an excellent effect of heat dissipation.

[0022] Incidentally, by performing a light press working other than the printing of the thick film 3 from the back surface of the substrate 1, by which to form a projection surface in the vicinity of the mounting portion, to achieve the same effect as the thick film 3 Of course.

3 and 4 show the configuration of the key switch device of this embodiment. Fixed contact pattern 2 on the substrate 1 described above
An inverted cup-shaped rubber spring 4 is placed as a switching member at a position corresponding to. The rubber spring 4 has a known movable contact inside, and a pressing shaft 82 of a shaft supporting portion A of a guide supporting member 6, which will be described later, is arranged opposite to the central portion of the upper surface thereof.

As a result, when the shaft support portion A moves downward with the depression of the key top 5, the pushing shaft 82 pushes down the rubber spring 4 , and when the pushing amount exceeds a certain limit , the rubber spring 4 buckles. The fixed contact pattern 2 is short-circuited by the movable contact in the rubber spring 4.

FIG. 4 is an exploded perspective view of the key switch device. In FIG. 4, the key top 5 is made of synthetic resin such as ABS resin, and letters such as alphabets are formed on the upper surface by printing or the like. ing. Further, from the back surface of the keytop 5, the rotation locking portion 5a and the sliding locking portion 5b are integrated with the keytop body 5 so as to correspond to the mounting portions 1a and 1c on the substrate 1 and face downward. It is provided.

The rotation locking portion 5a has a locking hole for rotatably locking a locking shaft 7b formed at one end of one of two link members 7, 8 which will be described later. And a sliding groove for locking the locking pin 8b formed at one end of the other link member 8 so as to be slidable in the horizontal direction is formed in the sliding locking portion 5b. ing.

A guide support member 6 for guiding and supporting the vertical movement of the key top 5 is arranged below the key top 5, and the guide support member 6 is composed of two link members 7 and 8.

As shown in FIG. 5, one link member 7 is formed in a U-shape in a plan view, and has a pair of plate-like bodies 71, and a locking shaft 7b is provided between one ends of each plate-like body 71. The plate 7 is formed integrally, and the locking pin 7 is provided on the other end of each plate 71.
a is formed. In addition, shafts 7c are formed in central portions of the respective plate-shaped bodies 71 which face each other, and the shafts 7c are formed in the respective plate-shaped bodies 81 of the link member 8 described later. It is rotatably supported by the shaft hole 8c.

Further, as shown in FIG. 6, the other link member 8 has a pair of plate-like bodies 81, and an engaging shaft 8a is integrally formed between one ends of the plate-like bodies 81, and A locking pin 8b is formed at the other end of each plate 81. In addition, between the central positions of the insides of the plate-shaped members 81, the link members 7 and 8 are mounted on the upper surface of the rubber spring 4 described above, and the link members 7 and 8 are rotated relative to each other when the key top 5 is pressed. Accordingly, a push-down shaft 82 that pushes down the rubber spring 4 is provided. This allows
When the key top 5 is pressed, the pressing shaft 82 presses the rubber spring 4 to perform the switching operation.

Axial holes 8c are provided at the central portions of the respective plate-shaped members 81, which are opposed to each other outside the plate-shaped members 81, and the plate-shaped members 7 of the link member 7 are provided in the axial holes 8c, respectively.
Each shaft body 7c formed in 1 is rotatably supported. As a result, both link members 7 and 8 can rotate by intersecting each other via each shaft body 7c and shaft hole 8c. Then, by this, the shaft body 7c, the shaft hole 8c, and the pressing shaft 8
2 forms a shaft support portion A.

The locking pin 7a and the locking shaft 7b of the link member 7 are arranged in a straight line with the shaft 7c as the center, and the distance from the shaft 7c is equal. The locking pin 8b and the locking shaft 8a of the link member 8 are arranged so as to be aligned with each other about the shaft hole 8c and have the same distance from the shaft hole 8c.

Further, as shown in FIG. 4, the guide support member 6
Is rotatably locked by a locking shaft 7b of the link member 7 in a locking hole formed in the rotation locking portion 5a of the key top 5 described above. Further, the locking pin 7a is locked to the mounting portion 1c formed on the substrate 1 which is slidably locked. In addition, the locking shaft 8a of the link member 8 is the substrate 1 described above.
It is rotatably locked to the mounting portion 1a that is rotationally locked. Further, the locking pin 8b is slidably locked in the locking groove formed in the sliding locking portion 5b of the key top 5 described above.

Further, as shown in FIG. 3, both link members 7 and 8 are formed by reducing the thickness of the tip of each plate-like body 71 and 81. Therefore, even when the key top 5 is pressed, the respective ends of the plate-shaped members 71 and 81 of the link members 7 and 8 do not come into contact with each other during the pressing of the key top 5. Therefore, the key top 5 is configured so as to be able to secure a sufficient key stroke without being hindered in its pressing operation.

Next, the operation of the key switch device having the above construction will be described. FIG. 7 is a sectional view of the key switch device.

In FIG. 7, when the key top 5 is pushed down, the locking shaft 7b of the link member 7 moves counterclockwise in the locking hole of the rotation locking portion 5a as the key top 5 moves downward. And the locking pin 8 of the link member 8
b slides horizontally (rightward in FIG. 7) in the locking groove of the sliding locking portion 5b. At the same time, the locking shaft 8a of the link member 8 rotates clockwise in the locking hole of the mounting portion 1a of the substrate 1 which is rotationally locked, and the locking pin 7a of the link member 7 slides. It slides horizontally (rightward in FIG. 7) in the locking groove of the mounting portion 1c to be stopped.

As a result, the shaft support A for supporting the link members 7 and 8 with respect to each other moves downward and gradually presses down the rubber spring 4, and when the pressing amount exceeds a certain limit, the rubber is stopped. The spring 4 is buckled. As a result, the movable contact in the rubber spring 4 short-circuits the fixed contact pattern 2 on the substrate 1 to perform a predetermined switching operation.

When the depression of the key top 5 is released, the shaft supporting portions A of both the link members 7 and 8 are pushed upward by the elastic restoring force of the rubber spring 4. Along with this, the locking shafts 7b and 8a and the locking pins 7a and 8b perform the reverse operation to the above, and as a result, the key top 5 is returned to the original position.

Since the locking shafts 7b and 8a do not move in the horizontal direction but only rotate in the locking holes, the key top 5 does not move in the horizontal direction. Therefore, the keys do not collide with the adjacent keys, and the keys are moved up and down while maintaining the horizontal state of the key surface of the key top 5.

As described above, the rubber spring 4 is substantially trapezoidal in side view, and the angle of the side surface due to the length and height of the upper bottom and the lower bottom of the rubber spring 4 is determined according to the desired key touch. Further, the height of this trapezoidal portion, that is, the height of the rubber spring 4 is determined according to the key stroke,
Higher is preferred. However, it is obvious that the rubber spring 4 cannot be made so large in view of the thickness of the entire device.

Further, as described above, since the thickness of the plate-like bodies 71, 81 of both link members 7, 8 on the tip side is made small in a side view, the keystroke operation is not interrupted during the operation. A sufficient stroke can be secured.

From the above, in the key switch device of the present invention, by forming the circuit board, the holder member, and the switch support plate in one structure, it is possible to increase the key stroke corresponding to the thinner keyboard. Therefore, it is possible to provide a key switch device which has good key operability and can reliably perform key input, and which is highly effective in reducing the number of parts, facilitating assembly, and reducing the weight of the device.

In general, the logic board, storage device, and power source of a portable computer are generally arranged under the keyboard, and a countermeasure against heat generated by these is a problem. In the key switch device of the present invention, a large number of holes (blank portions 1b) provided in the substrate function as cooling holes, so that heat can be effectively radiated. Also in this respect, the present invention has an ideal structure.

In addition to the above effects, in particular, in the key switch device according to the present embodiment, the configuration for guiding the key stem by the key holder portion can be completely eliminated.
Unlike conventional key switch devices, there is no sliding noise between the key stem and the key holder when the key is pressed, and it is not necessary to reduce the key operation area to press the center of the key. It completely disappears.

Further, in the key switch device according to the present embodiment, the locking hole of the rotary locking portion 5a and the mounting portion 1 for rotary locking.
Each of the locking shafts 7b and 8a locked in the locking hole of “a” does not move horizontally even when the key top 5 is pressed, and only rotates in the locking hole. It is not moved horizontally. Therefore, it is possible to provide a key switch device which is excellent in key operability and can surely perform a key input without collision between adjacent keys.

The present invention is not limited to the above-mentioned embodiment, and various modifications can be made without departing from the gist of the present invention.
It can be improved. For example, the link members 7 and 8 in this embodiment may be members of the same kind combined in a pantograph shape.

Further, in this embodiment, the link members 7 and 8 are
Although the rubber spring 4 is pushed down by the shaft support portion, the rubber spring 4 may be pushed down by the link members 7, 8 or another member provided on the key top 5.

[0047]

As described above, according to the key switch device of the present invention, the substrate, the electric circuit pattern, and the locking portion for locking the end portion of the link member are integrally formed, and thus the component The score can be reduced. At the same time, a key switch that has a simple structure, is compatible with miniaturization and thinning of the keyboard, and can secure a sufficient key stroke, has good operability of key input and enables reliable key input. It becomes possible to provide a device.

[Brief description of drawings]

FIG. 1 is a top view of a substrate of a key switch device according to an embodiment.

FIG. 2 is a side sectional view of the substrate of FIG.

FIG. 3 is a perspective view of a substrate and components of this embodiment.

FIG. 4 is an exploded perspective view of the key switch device according to the present embodiment.

FIG. 5 is a plan view of a link member of this embodiment.

FIG. 6 is a plan view of the other link member of this embodiment.

FIG. 7 is a cross-sectional view of the key switch device of the present embodiment.

FIG. 8 is a diagram showing an example of the shape of thick film printing of the key switch device of the present embodiment.

FIG. 9 is an enlarged view of the vicinity of the mounting portion of the key switch device of the present embodiment.

[Explanation of symbols]

1 substrate 1a Mounting part for rotation locking 1c Mounting part that slides and locks 2 Fixed contact pattern 3 thick film 4 Rubber spring 5 key tops 6 Guide support member 7 Link members 8 link members

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01H 13/14 G06F 3/02 310 H01H 11/00

Claims (2)

(57) [Claims] 1. A substrate having a plastically deformable metal material, a circuit pattern printed on the surface of the substrate, and fixed contacts formed in the circuit pattern. A fixed contact pattern formed by printing on the front surface, and a fixed contact pattern provided in correspondence with the fixed contact pattern
A key top having a locking portion; a link member having one end locked to the first locking portion of the key top and vertically guiding and supporting the key top; and a vertical movement of the key top. And a movable contact that performs a switching operation between the fixed contact and the fixed contact, and a second locking portion that locks the other end of the link member is formed on the substrate. apparatus. 2. The key switch according to claim 1, wherein the second locking portion is composed of a rotation locking portion and a sliding locking portion by press working from the back surface of the substrate. apparatus.