WO2020170896A1

WO2020170896A1 - Switch device and key input device

Info

Publication number: WO2020170896A1
Application number: PCT/JP2020/005233
Authority: WO
Inventors: 賢紀杉原; 成信岸; 智高盛; 光一古澤
Original assignee: オムロン株式会社
Priority date: 2019-02-20
Filing date: 2020-02-12
Publication date: 2020-08-27
Also published as: JP2020136103A; TWI738212B; JP7059964B2; TW202032599A

Abstract

Provided are a switch device and a key input device which can generate a click sound and a recognizable sound accompanying a pressing operation on a key top.　The switch device that can be used for the key input device comprises: a fixed member 10; a movable member that is moved in a pressing direction by the pressing operation; an elastic member that presses the movable member in a direction opposite to the pressing direction; and a contact point member that switches an electric connection/disconnection state while the movable member is moved in the pressing direction. The switch device further comprises: an interlocking member 17 that operates in conjunction with the movement of the movable member; a swinging member 15 that is swung by being pressed by the interlocking member 17; and a support member 16 that swingably supports the swinging member 15. When the connection/disconnection state is switched due to the movement of the movable member in the pressing direction in response to a pressing operation of a user, the swinging member 15 swings and hits the support member 16 due to the pressing in conjunction with the movement of the movable member, thereby generating a sound.

Description

Switch device and key input device

The present invention relates to a switch device that switches an electrical contact/separation state by pressing a movable member, and a key input device equipped with such a switch device.

As an input device for electronic devices such as computers, keyboards in which a plurality of key switches are arranged side by side are widely used. For example, Patent Document 1 describes a push button switch that gives a reliable feel when closing a switch contact. Further, in recent years, various demands for a user to quickly react and operate a keyboard used for a computer game called esports are increasing.

Japanese Patent Publication No. 4-47932

However, for example, keyboard switches used for e-sports are required to improve the sound generated when the key switch is pressed, so-called click sound, because the user reacts quickly.

The present invention has been made in view of such circumstances, and a main object of the present invention is to provide a switch device such as a key switch having an improved sound generated when the button is pressed.

Another object of the present invention is to provide a key input device such as a keyboard using such a switch device.

In order to solve the above problems, a switch device (key switch) according to the present application includes a fixed member, a movable member that moves in a pressing direction by a pressing operation, and an elastic member that presses the movable member in a direction opposite to the pressing direction, A switch device comprising: a contact member that switches an electrical contact/separation state in the process of moving the movable member in the pressing direction, the swing device being pressed and rocked as the movable member moves; A supporting member that supports the moving member so as to be swingable, and the swinging member strikes the supporting member by swinging.

In the switch device, the swing member has a cantilever structure in which a first end is a fixed end supported by the support member and a second end different from the first end is a free end. The two end sides are urged in the first direction, and are urged by the movement of the movable member in a second direction opposite to the first direction to swing.

Further, in the switch device, the swing member is formed by branching a bow spring portion, and a branched tip end of the bow spring portion is fixed to the support member, and the bow spring portion serves to It is characterized in that the second end side is biased in the first direction or the second direction.

In addition, the switch device includes an interlocking member that operates in conjunction with the movement of the movable member, and the swinging member is swung by being pressed by the interlocking member that operates in conjunction with the movement of the movable member. It is characterized by

Further, in the switch device, the interlocking member is configured as a cam mechanism that follows the movement of the movable member by sliding on the moving movable member, and the interlocking member is configured by the cam mechanism. Operates in a direction different from the moving direction of the movable member.

Further, the key input device (keyboard) described in the present application is a key input device in which a plurality of key switches are arranged, and the arranged key switch is any one of claims 1 to 5. It is characterized by comprising the switch device described.

In the switch device and the key input device described in the present application, when the push member is pushed, the swing member swings along with the movement of the movable member, and strikes the support member.

A switch device and a key input device according to the present invention include a movable member that moves in a pressing direction by a user's pressing operation, and a swinging member that is swingably supported by a support member, and can be used for moving the movable member. The accompanying pressure causes the rocking member to rock and strike the support member. As a result, the present invention has an excellent effect such as generating a sound accompanying the pressing operation.

It is a schematic perspective view which shows an example of the external appearance of the keyboard to which the key input device of this application is applied. It is a schematic perspective view which shows an example of the external appearance of the key switch of this application description. It is a schematic perspective view which shows an example of the external appearance of the key switch of this application description. It is a schematic disassembled perspective view which shows an example of the key switch of this application description. It is a schematic sectional drawing which shows an example of the key switch of this application. It is a schematic sectional drawing which shows an example of the rocking|fluctuation member and support member with which the key switch of this application is provided. It is a schematic sectional drawing which shows an example of the key switch of this application. It is a schematic sectional drawing which shows an example of the key switch of this application. It is a schematic sectional drawing which shows an example of a rocking|swiveling member, a supporting member, and an interlocking member with which the key switch of this application is described. It is a schematic sectional drawing which shows an example of a rocking|swiveling member, a supporting member, and an interlocking member with which the key switch of this application is described.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The key input device described in the present application is used, for example, as a keyboard KB used for inputting data such as various commands in addition to characters, numbers and symbols to an electronic device such as a computer.

FIG. 1 is a schematic perspective view showing an example of the appearance of a keyboard KB to which the key input device described in the present application is applied. On the keyboard KB, a plurality of key switches 1 such as character keys, numeric keys, and other function keys are arranged side by side as a switch device. In the keyboard KB illustrated in FIG. 1, the key switches 1 having the same shape are arranged side by side for the purpose of simplifying the structure and easily recognizing the technical contents, but the shape is limited to such a shape at the time of mounting. Not a thing. For example, when applied to a keyboard KB of a QWERTY layout, only the character keys have the same shape, and the key switch 1 having a specific function such as an enter key arranged around the character keys has a shape different from that of the character keys. It is possible to design as appropriate.

Next, the key switch 1 arranged on the keyboard KB will be described. The key switch 1 included in the keyboard KB described in the present application can be realized in various forms, and here, a part of the forms will be described as an example.

Explain the structure of the key switch 1. 2A and 2B are schematic perspective views showing an example of the external appearance of the key switch 1 described in the present application. The key switch 1 includes a fixing member 10 that is fixed to a board built in the keyboard KB and a movable member 11 that is vertically movable and is pushed downward by a user's pressing operation. A key top 12 is detachably attached to the upper end of the movable member 11 as a pressed member that receives a pressing operation by the user. The keytop 12 and the movable member 11 move downward by the pressing by such a pressing operation, and move upward when released from the pressing by the pressing operation. 2A shows a state in which the key top 12 is attached, and FIG. 2B shows a state in which the key top 12 is removed.

As shown in FIG. 2A, the user can operate the keyboard KB with the key top 12 attached to the key switch 1. When the user touches the key top 12 of the key switch 1 arranged on the keyboard KB and performs an operation of depressing the key top 12, the contact/separation state of the electric circuit in the key switch 1 is switched and the contact/separation state is changed. The ON signal for each key switch 1 is output from the keyboard KB that has detected the switching to an electronic device such as a connected personal computer. Further, by releasing the depression of the key top 12, the key switch 1 released from the depression ascends and returns to the original position.

Describe the internal structure of the key switch 1. FIG. 3 is a schematic exploded perspective view showing an example of the key switch 1 described in the present application. FIG. 4 is a schematic sectional view showing an example of the key switch 1 described in the present application. FIG. 4 shows a cross section of the key switch 1 taken along a vertical plane passing through AB shown in FIG. 2B. The key switch 1 includes various members and mechanisms such as the elastic member 13, the contact member 14, the swinging member 15, the support member 16, and the interlocking member 17 in addition to the fixed member 10, the movable member 11, and the key top 12 described above. There is. In FIGS. 3 and 4, the key top 12 is omitted. In addition, for convenience of description, in the following description, the up, down, left, and right directions will be described as up, down, left, and right with respect to each member.

The fixing member 10 is a casing having a substantially rectangular parallelepiped shape, and is formed by combining an upper half body 10a and a lower half body 10b as shown in FIG. A substantially square insertion opening 100 for inserting the movable member 11 is provided on the upper surface of the fixed member 10. From the lower surface of the fixing member 10, a leg portion 101 for fixing the key switch 1 to the substrate and a terminal 140 described later are projected.

　Inside the fixing member 10, a double inner wall is projected from the bottom. The inner first inner wall 102 has a cylindrical shape, and the outer second inner wall 103 has a rectangular tube shape. Inside the first inner wall 102, members such as a prismatic pressing column 110 extending from the lower surface of the movable member 11, a swinging member 15, a supporting member 16, and an interlocking member 17 are arranged. Between the first inner wall 102 and the second inner wall 103, an elastic member 13 such as a compression coil spring that presses the movable member 11 in a direction opposite to the pressing direction is attached. The elastic member 13 has a lower end attached to the inner bottom surface of the fixed member 10 and an upper end pressing the movable member 11 upward. On the outer side of the second inner wall 103, a contact member 14 that serves as a switch for switching between electrical contact and separation states is erected by press fitting on the inner bottom surface of the fixing member 10. The contact member 14 has a rectangular tubular shape formed by molding and combining two metal plates, and is fitted so as to surround the periphery of the second inner wall 103. Further, from the lower end of the contact member 14, two terminals 140 respectively extending from the two metal plates protrude downward. The two terminals 140 penetrate the bottom of the fixing member 10 and further project downward from the lower surface of the fixing member 10.

The movable member 11 has a substantially rectangular parallelepiped outer shape. An attachment portion 111 for attaching the key top 12 is formed on the upper portion of the movable member 11. In the vicinity of the center of the lower part of the movable member 11, a prismatic pressing column 110 extending downward from the lower surface side is formed. One of the side surfaces of the pressing column 110 is formed as a pressing surface 110a that is tapered from the vicinity of the center to the lower end, and presses the interlocking member 17 by the pressing surface 110a. On the lower surface of the movable member 11, a fitting groove 112 into which the upper end of the elastic member 13 is fitted is provided in a substantially annular recess. Further, the pair of opposite side surfaces of the movable member 11 are formed as a pair of pressing side walls 113 extending downward. A first pressing protrusion 113a for pressing the contact member 14 is provided inwardly in the vicinity of the lower end of the pressing side wall 113 of the movable member 11.

The movable member 11 is located at the upper end of the movement range (hereinafter, referred to as top dead center) when the key top 12 is not pressed by the pressing operation, and when the key top 12 is pressed, the lower end of the movement range (hereinafter, lower). Move to the dead point). When released from the pressure, the movable member 11 is pressed upward by the elastic member 13 and moves from the bottom dead center to the top dead center.

The contact member 14 is erected on the inner bottom surface around the second inner wall 103 of the fixing member 10, and has two terminals 140 protruding downward from the lower surface of the fixing member 10. The contact member 14 is formed with a contact/separation portion 141 that opens and closes the electric circuit of the key switch 1 by receiving a pressing action associated with the movement of the movable member 11. The contact/separation part 141 of the contact member 14 is configured by two metal plates forming the contact member 14 so that the fixed piece 141a forming the side surface of the contact member 14 and the movable piece 141b that is bent by pressing overlap. Has been done. The fixed piece 141a is located outside the movable piece 141b, and the movable piece 141b is located inside the fixed piece 141a. The movable piece 141b is pressed by the first pressing protrusion 113a of the moving movable member 11 and is bent inward to separate from the fixed piece 141a. When the pressing is released, the movable piece 141b returns to its original shape and the fixed piece 141a. Contact with. It should be noted that contacts are provided so as to project from the surfaces of the fixed piece 141a and the movable piece 141b that face each other. The separation/contact between the fixed piece 141a and the movable piece 141b formed of the two metal plates forming the contact point member 14 is such that the electric circuit according to the key switch 1 is connected to the two terminals 140 of the contact point member 14. Is opened and closed, and an ON signal based on the opening and closing is output from the keyboard KB to the electronic device.

The interlocking member 17 is formed in a prismatic shape with a cutout recessed so that the bottom surface has a substantially U shape in a top view. The surface corresponding to the inner bottom of the U-shaped recess is formed as a pressed surface 170 that is tapered upwardly, and the pressing surface 110 a formed on the pressing column 110 of the movable member 11 is formed. Abut. A second pressing protrusion 171 for pressing the swinging member 15 is provided on the surface opposite to the pressed surface 170 corresponding to the outside of the bottom of the U-shaped recess. The operation direction of the interlocking member 17 is regulated by a regulation portion (not shown) formed inside the first inner wall 102 of the fixing member 10, and the lateral direction, from the viewpoint illustrated in FIG. It works only in the horizontal direction.

The interlocking member 17 forms a slide cam mechanism by cooperating with the pressing column 110 of the movable member 11, and operates in the lateral direction (left and right direction in FIG. 4) in conjunction with the vertical movement of the movable member 11. To do. More specifically, the pressing column 110 of the movable member 11 is arranged so that the pressing surface 110a formed with an inclination contacts the pressed surface 170 of the interlocking member 17 formed with an inclination. Then, when the movable member 11 moves downward, the pressing surface 110 a formed on the pressing column 110 of the movable member 11 slides while pressing the pressed surface 170 of the interlocking member 17, whereby the interlocking member 17 becomes It follows the movement of the movable member 11. That is, the interlocking member 17 operates as a cam slider that follows the movement of the movable member 11 that operates as a cam driver. Since the operation direction of the interlocking member 17 that operates as a cam slider is restricted to the lateral direction, the interlocking member 17 operates so as to move leftward in FIG. That is, the interlocking member 17 operates in the lateral direction different from the vertical direction, which is the moving direction of the movable member 11, by the slide cam mechanism in which the movable member 11 and the interlocking member 17 are formed in cooperation with each other. The interlocking member 17 presses the rocking member 15 leftward (first direction) by operating in conjunction with the movable member 11. Further, when the movable member 11 rises to the top dead center and the interlocking member 17 is released from the pressing force of the movable member 11, the interlocking member 17 is pressed in the right direction (second direction) by the swing member 15 and moves in the right direction. Move to and return to the original position.

The swinging member 15 and the supporting member 16 are mechanisms that generate a sound when the key top 12 is pressed. The rocking member 15 is formed of a flexible metal thin plate, and the supporting member 16 fixes and supports the rocking member 15 inside the first inner wall 102 of the fixing member 10.

FIG. 5 is a schematic cross-sectional view showing an example of the swinging member 15 and the supporting member 16 included in the key switch 1 described in the present application. FIG. 5 shows the swing member 15, the support member 16, and the interlocking member 17 out of the configuration of the key switch 1 in an enlarged manner. The configurations of the swing member 15, the support member 16, and the interlocking member 17 will be further described with reference to FIGS. 3 to 5. The supporting member 16 that supports the swinging member 15 has a first supporting portion 160 at the lower end and a second supporting portion 161 near the center above the first supporting portion 160, and the first supporting portion 160. The swing member 15 is supported by the second support portion 161. On the upper side of the support member 16, an impacted portion 162 that projects toward the swing member 15 is formed on the left side of the upper end of the swing member 15.

The swing member 15 is disposed inside the first inner wall 102 of the fixed member 10 so as to be supported by the support member 16, and is formed using a thin plate-shaped metal extending in the vertical direction. The lower end (first end) side of the swing member 15 is a fixed end supported by the first support portion 160 of the support member 16, and functions as a swing fulcrum 150. The upper end (second end) side of the rocking member 15 is a free end arranged so as to face the hitting portion 162 of the supporting member 16, and functions as the hitting portion 151 for hitting the supporting member 16. .. That is, the swinging member 15 has a cantilever structure in which the lower end side is the fixed end and the upper end side is the free end, and swings about the fixed end so that the free end side bends. Further, the swinging member 15 is formed with a tongue-shaped piece that is punched out in the vicinity of the center in a tongue shape and branched from the upper end side to the lower end side, and the tongue-shaped piece is bent in an arc shape to form a bow spring portion 152. Has become. The tip of the branched bow spring portion 152 is supported by the second support portion 161 of the fixing member 10. The bow spring portion 152 functions as a return spring that generates a reaction force against the pressing when the swinging member 15 is pressed by the interlocking member 17 and bent to the left. The interlocking member 17 is disposed so as to come into contact with a portion of the swinging member 15 supported by the first supporting portion 160 and a portion of the swinging member 15 supported by the second supporting portion 161.

Describe the operation of the key switch 1 described in the present application. 6A and 6B are schematic cross-sectional views showing an example of the key switch 1 described in the present application. 7A and 7B are schematic cross-sectional views showing an example of the swing member 15, the support member 16, and the interlocking member 17 included in the key switch 1 described in the present application.

6A and 7A show a state in which the key top 12 of the key switch 1 is not pressed by the user's pressing operation. When the key switch 1 is not pressed, the movable member 11 is located at the top dead center. When the movable member 11 is located at the top dead center, the interlocking member 17 is in a state where it is not pressed by the movable member 11. Further, in the swinging member 15, the impact portion 151 side is bent to the right by the bias of the bow spring portion 152, and the interlocking member 17 is pressed to the right. Therefore, when the key switch 1 is not pressed, the movable member 11 is located at the top dead center, the interlocking member 17 is located on the right side within the movement range, and the swinging member 15 is hit by the bow spring portion 152. The 151 side is pressed to the right.

6B and 7B show a state in which the key top 12 of the key switch 1 is pressed by the user's pressing operation and the movable member 11 is moved to the bottom dead center. When the movable member 11 moves to the bottom dead center, the pressing surface 110a formed on the pressing column 110 of the movable member 11 contacts the pressed surface 170 of the interlocking member 17 and slides while pressing the pressed surface 170. To do. The interlocking member 17 pressed by the movable member 11 operates as a cam slider that follows the movement of the movable member 11, moves to the left and presses the swinging member 15 by the second pressing protrusion 171. The rocking member 15 pressed by the interlocking member 17 rocks to the left around the rocking fulcrum 150 supported by the first supporting portion 160. When the swinging member 15 is further pushed to the left by the interlocking member 17 that is interlocked with the movable member 11 that moves to the bottom dead center, the swinging member 15 swings with the bow spring portion 152 supported by the second support portion 161. , The bow spring portion 152 bends to cause a snap action of reversing. When the bow spring portion 152 is inverted, the hitting portion 151 of the swinging member 15 is swiftly bent to the left side, hitting the hitting portion 162 of the supporting member 16, and sound and vibration are generated at the time of hitting. To do. In addition, in the process in which the movable member 11 moves from the top dead center to the bottom dead center, the first pressing protrusion 113a provided on the pressing sidewall 113 of the movable member 11 presses the movable piece 141b of the contact member 14, The contact/separation state of the member 14 is switched. When the contact/separation state of the contact member 14 is switched, an ON signal indicating that the key switch 1 is pressed is output from the keyboard KB to the electronic device.

That is, when the user presses down the key top 12 to move the movable member 11 in the pressing direction and the contact/separation state of the contact member 14 is switched, the hitting portion 151 of the swinging member 15 causes the hitting portion 151 of the supporting member 16 to be covered. An impact sound that impacts the impact section 162 is generated, and vibration associated with the impact is generated. Therefore, the user recognizes the hitting sound generated as a click sound and the vibration associated with the hitting as a click feeling. The impact of the supporting member 16 by the swinging member 15 is preferably such that the impact sound that the user recognizes as a click sound is generated and the vibration accompanying the impact is recognized as a click feeling. Further, it is possible to adjust the impact sound and vibration by attaching the elastic member 13 such as resin to the support member 16, and by adjusting the impact sound and vibration, the click sound and the click feeling are adjusted. It

Note that sound and vibration are generated even when the swinging member 15 is inverted, so the material, shape, and arrangement of each member are configured so that the sound and vibration generated by the inversion can be recognized as a click sound and a click feeling. It may be designed.

After the movable member 11 has moved to the bottom dead center, the user releases the pressing of the key top 12 and the movable member 11 released from the pressing moves to the top dead center by being pressed by the elastic member 13 from below. To do. Further, when the movable member 11 moves to the top dead center, the interlocking member 17 is released from the pressure from the movable member 11. The swinging member 15 is biased rightward by the bow spring portion 152 on the side of the hitting portion 151, so that the hitting portion 151 side swings rightward with the first support portion 160 as the swing axis, and the bow spring. The portion 152 returns from the inverted state, and the impact portion 151 side is further urged to bend the impact portion 151 side to the right. Further, the swinging member 15 is bent to the right side by the biasing force of the bow spring portion 152 and also by swinging around the first support portion 160 as the swing axis. When the rocking member 15 bends to the right, the interlocking member 17 released from the pressing of the movable member 11 is pressed by the rocking member 15 and moves to the right. Then, the state returns to the state shown in FIGS. 6A and 7A.

As described above, in the key switch 1 described in the present application, the movable member 11 moves downward in response to the user's pressing operation, and the interlocking member 17 that follows the movement of the movable member 11 presses the swinging member 15. The rocking member 15 rocks by pressing and hits the support member 16 to generate sound and vibration. The generated sound and vibration are generated when the electrical contact/separation state is switched in the process of moving the movable member 11 in the pressing direction, and thus the user recognizes the generated sound and vibration as a click sound and a click feeling. .. When the user recognizes the click sound and the click feeling, the user recognizes that the operation is completed and can quickly perform the next operation. Therefore, since the user can quickly react and perform operations one after another, the key switch 1 and the keyboard KB described in the present application are suitable for a switch and a keyboard KB used for a computer game such as esports.

The present invention is not limited to the embodiments described above, and can be implemented in various other forms. Therefore, the embodiments described above are merely examples in all respects, and should not be limitedly interpreted. The technical scope of the present invention is described by the scope of the claims, and is not bound by the text of the specification. Furthermore, all modifications and changes belonging to the equivalent range of the claims are within the scope of the present invention.

For example, in the above-described embodiment, the swing member 15 having the bow spring portion 152 is used, but the present invention is not limited to this, and any swing member 15 capable of generating sound can be used. It is possible to develop into forms. For example, a thin metal plate formed as a leaf spring without the bow spring portion 152 formed as the swinging member 15 can be developed in various forms.

Further, in the above-described embodiment, the mode in which the swing member 15 is pressed from the movable member 11 via the interlocking member 17 is shown, but the present invention is not limited to this, and the movable member 11 directly presses the swing member 15. It is also possible to form it. Further, a mechanism in which the movable member 11 and the interlocking member 17 interlock with each other can be appropriately designed, and the movable member 11 and the interlocking member can be configured by using a cam other than the slide cam, and other structures such as a link, a gear, and a crank. The interlocking member 17 may be interlocked, and in this case, the interlocking member 17 can be appropriately designed such that the operating direction is other than the lateral direction.

Furthermore, for example, in the above-described embodiment, the form applied to the key input device for mainly inputting characters such as the keyboard KB is shown, but the present invention is not limited to this. For example, the present invention can be applied to a key input device dedicated to numeric keys such as a numeric keypad, and various electronic input devices other than a computer, for example, various key input devices such as various switches used for a game dedicated device.

KB keyboard (key input device)
1 key switch (switch device)
10 Fixed Member 11 Movable Member 110 Push Column 110a Push Surface 12 Key Top 13 Elastic Member 14 Contact Member 15 Swing Member 150 Swing Support Point (First End/Fixed End)
151 Impact part (second end/free end)
152 Bow Spring Part 16 Supporting Member 160 First Supporting Part 161 Second Supporting Part 162 Hitting Part 17 Interlocking Member 170 Pressed Surface

Claims

A fixed member, a movable member that moves in the pressing direction by a pressing operation, an elastic member that presses the movable member in a direction opposite to the pressing direction, and an electrical contact/separation state in the process of moving the movable member in the pressing direction. A switch device comprising a contact member for switching,
A swing member that is pressed and swings as the movable member moves,
A supporting member for swingably supporting the swing member,
The switch device, wherein the swing member strikes the support member by swinging.
The switch device according to claim 1, wherein
The swing member is
A first end is a fixed end supported by the support member, and a second end different from the first end is a free end, forming a cantilever structure,
The second end side is biased in the first direction,
A switch device characterized by being pressed in a second direction opposite to the first direction by the pressing caused by the movement of the movable member and swinging.
The switch device according to claim 2, wherein
The swing member is
The bow spring part is branched and formed,
The branched tip of the bow spring portion is fixed to the support member,
A switch device characterized in that the bow spring portion urges the second end side in a first direction or a second direction.
The switch device according to any one of claims 1 to 3, wherein:
The interlocking member that operates in conjunction with the movement of the movable member is provided,
The switch device, wherein the swinging member is pushed and swung by the interlocking member operating in conjunction with the movement of the movable member.
The switch device according to claim 4, wherein
The interlocking member is configured as a cam mechanism that follows the movement of the movable member by sliding on the moving movable member,
The interlocking member operates in a direction different from the moving direction of the movable member by the cam mechanism.
A key input device provided with a plurality of key switches,
A key input device comprising the switch device according to any one of claims 1 to 5 as the arranged key switch.