TW201801115A - Button device for elevator capable of achieving the effect of improving the operation reliability and comprising a button holder, a circuit module, a connecting rod set, a button, and a linkage elastic piece - Google Patents

Abstract

A button device for elevator mainly comprises a button holder and a button provided on the button holder, two connecting rods pivotally connected between the button holder and the button, and a linkage elastic piece latchedly connected between the two connecting rods. The two connecting rods are pivotally arranged on the button holder in a mirror-symmetrical manner and simultaneously abutted on one side of the button facing the button holder, so that the two connecting rods are pivotally connected with each other to operate synchronously regardless of which position the button is pressed. When the two connecting rods operate synchronously, they will further drive the linkage elastic piece so that the linkage elastic piece and a switch provided in the button holder form an electrical conduction, thereby achieving the effect of improving the operation reliability.

Description

Button device for elevator

The present invention relates to the keys of an elevator, and more particularly, to a key device capable of improving the reliability of an operation.

The elevator is mainly used to provide the carrying function. When people enter the elevator, they usually use the opening and closing button to control the elevator door to close, and then use the floor button to select the floor they want to reach. At this time, the elevator will move to the passenger. The selected floor.

However, whether it is an on / off button or a floor button, in order to restore the initial state immediately after the pressing force is released, in the prior art, the back of the button is usually provided with two oppositely arranged springs to provide a reset effect on the button. However, due to the lack of structural linkage between the two springs, as long as the position of the push is deviated, the key may not be able to form electrical conduction with the internal circuit board. At this time, the passenger must release the pressing force before Change the position and press again until it succeeds. Therefore, the structure of the traditional spring button is not ideal.

The main object of the present invention is to provide a key device for an elevator, which has a good operation reliability.

In order to achieve the above object, the key device for an elevator provided by the present invention includes a key base, a circuit module, a link group, a key, and a linkage spring. The key base has a circuit board mounting portion, two opposing first pivot portions and two opposing second pivot portions, and the two first and second pivot portions are disposed side by side on the circuit board mounting portion. The two opposite sides; the circuit module has a circuit board and a switch, the circuit board is provided on the circuit board mounting portion of the keypad, the switch is provided on the circuit board and has a trigger portion; the link group has a A first link and a second link opposite to the first link, the first link having two opposing third pivot portions and two opposing fourth pivot portions, the second link having two The opposite fifth pivotal portion and the two opposite sixth pivotal portions, wherein the third pivotal portion of the first link and the fifth pivotal portion of the second link are pivoted to each other, and the first The fourth pivotal portion of a link and the sixth pivotal portion of the second link are pivotally connected to the first and second pivotal portions of the key holder, respectively; the key is displaceably disposed on the key holder and the card Connected to the first and second links of the link group, so that the button can push the first and second links of the link group by external force. The two ends of the interlocking spring are respectively provided on the first and second links, so that the interlocking spring can be driven by the first and second links, and the interlocking spring has a pressing portion. The pressing portion corresponds to the trigger portion of the switch, so that the linkage spring can form electrical conduction with the trigger portion of the switch through the pressing portion in the process of following the first and second links.

It can be known from the above that the key device of the present invention utilizes the configuration of the first and second links, so that when any position of the key is pressed, the linked spring can be driven by the synchronous action of the first and second links. The switch is reliably contacted to achieve the purpose of improving the operation reliability.

In the present invention, the key base further has two opposite elastic piece fixing portions, and the key device further includes a compressed elastic piece, the length direction of the compressed elastic piece is perpendicular to the length direction of the linked elastic piece, and both ends of the compressed elastic piece The elastic piece fixing portions are respectively clamped to one of the key bases, and the compressed elastic piece has a pressure receiving portion which is interposed between the trigger portion of the switch and the pressing portion of the linked elastic piece. Therefore, when the linked elastic piece is driven by the first and second links, the pressing portion of the linked elastic piece will first push up the pressed portion of the compressed elastic piece, and then the pressed portion of the compressed elastic piece will Touching the trigger part of the switch completes the electrical conduction, which can increase the use of the button.

In the present invention, the first pivoting portion of the key base has a first outer wall and a first inner wall. The first outer wall has a first pivot hole. The first inner wall has a first pivot slot. The fourth pivotal portion of the first link is a convex shaft, and one end of the fourth pivotal portion is pivotably passed through the first pivot hole of the first outer wall. The fourth pivotal portion The other end is pivotably snapped into a first pivot groove of the first inner standing wall. The second pivotal connection portion of the key base has a second outer standing wall and a second inner standing wall. The second outer standing wall has A second pivot hole, the second inner wall has a second pivot groove, a sixth pivot joint portion of the second link is a convex shaft, and one end of the sixth pivot joint portion is pivotably passed through the second pivot hole. In the second pivot hole of the second outer wall of the key base, the other end of the sixth pivot joint portion is pivotably engaged with the second pivot groove of the second inner wall of the key base. With this, on the one hand, the first and second connecting rods can be easily assembled, and on the other hand, the first and second connecting rods can be prevented from being accidentally loosened during the operation.

In the present invention, the key base has a terminal base mounting groove adjacent to the circuit board mounting portion, and the circuit module further has a terminal base. The terminal base is located in the terminal base mounting groove of the key base and is connected. The circuit board. Therefore, the key device of the present invention can be connected to an external controller through the terminal base, so as to simplify the wire drawing operation and increase the installation convenience.

The detailed structure, characteristics, assembling or using method of the key device provided by the present invention will be described in the detailed description of the subsequent embodiments. However, those having ordinary knowledge in the field of the present invention should understand that the detailed descriptions and the specific embodiments listed in the implementation of the present invention are only used to illustrate the present invention, and are not intended to limit the scope of the patent application of the present invention.

Please refer to FIGS. 1, 2 and 7 first. The key device 10 of the present invention is mounted on an elevator panel (not shown) through a fixing piece 12. The key device 10 includes a key base 20, a circuit module 30, A link group 40, a button 50, a linked elastic sheet 60, a compressed elastic sheet 70, and a backlight module 80.

As shown in FIG. 2, the key base 20 has one end wall 21. The end wall 21 has a circuit board mounting portion 23 and a terminal seat mounting groove 24 adjacent to the circuit board mounting portion 23. On the opposite sides, a first pivoting portion 25, a second pivoting portion 26 juxtaposed to the first pivoting portion 25, and an elastic piece fixing portion 27 interposed between the first and second pivoting portions 25 and 26, respectively. . As shown in FIG. 3, the first pivot connection portion 25 has a first outer wall 251 and a first inner wall 252, the first outer wall 251 has a first pivot hole 253, and the first inner wall 252 has a first The pivot groove 254 and a first cut groove 255 communicating with the first pivot groove 254. The second pivot joint portion 26 has a second outer wall 261 and a second inner wall 262. The second outer wall 261 has a second pivot hole. 263. The second inner upright wall 262 has a second pivot groove 264 and a second cut groove 265 communicating with the second pivot groove 264. In addition, the key base 20 further has a peripheral wall 22, which is connected to the peripheral edge of the end wall 21 and has four first stop portions 28 facing each other.

The circuit module 30 has a circuit board 31, a switch 32, and a terminal base 33. The circuit board 31 is provided on the circuit board mounting portion 23 of the key base 20. The switch 32 is provided on the circuit board 31 and has a trigger portion 322 and terminal base. 33 is provided in the terminal base mounting groove 24 of the key base 20, and the terminal base 33 can be installed in different directions according to actual needs. For example, in FIG. 1, the opening direction of the terminal base 33 faces the side of the key base 20. In FIG. 8, the opening direction of the terminal base 33 is directed to the lower side of the key base 20. However, in either way, the circuit module 30 can use the wiring between the terminal base 33 and an external controller (not shown) as The connection can solve the problem of the wire pull caused by the traditional wire bonding, thereby increasing the convenience of installation.

As shown in FIG. 2, the link group 40 has a first link 41, and the first link 41 has a first main lever body 42 and two opposite first side lever bodies 43. A first clamping shaft 421 extends outward at the two ends, and a first through slot 422 is formed in the center of the first main rod body 42. One end of each first side rod body 43 is connected to one end of the first main rod body 42. The other end of the one-side lever body 43 has a third pivoting portion 431. The third pivoting portion 431 is a convex shaft in this embodiment. Each of the first-side lever bodies 43 further has a first shaft 421 and a first shaft 421. The fourth pivoting portion 432 between the three pivoting portions 431 is a convex shaft in this embodiment.

The connecting rod group 40 further has a second connecting rod 44. The second connecting rod 44 has a second main rod body 45 and two opposite second side rod bodies 46. Both ends of the second main rod body 45 respectively extend outward. A second clamping shaft 452, a center of the second main rod body 45 has a second through slot 454, one end of each second side rod body 46 is connected to one end of the second main rod body 45, The other end has a fifth pivoting portion 461. The fifth pivoting portion 461 is a groove in this embodiment. Each of the second side rods 46 further has a position between the second clamping shaft 452 and the fifth pivoting portion 461. The sixth pivoting portion 462 is a convex shaft in this embodiment.

When assembling the first link 41, as shown in FIGS. 2 to 4, one end of the fourth pivotal connection portion 432 of the first link 41 is first inserted through the first outer portion of the first pivotal connection portion 25 of the key base 20. In the first pivot hole 253 of the vertical wall 251, the other end of the fourth pivotal connection portion 432 of the first link 41 is then engaged with the first pivot of the first inner vertical wall 252 of the first pivotal connection portion 25 of the key base 20. In the groove 254, the assembly between the first link 41 and the key base 20 is completed in this way. At this time, the first link 41 can pivot relative to the key base 20 with the fourth pivot joint 432 as the axis. In addition, when assembling the second link 44, one end of the sixth pivot joint portion 462 of the second link 44 first passes through the second pivot hole 263 of the second outer wall 261 of the second pivot joint portion 26 of the key base 20. The other end of the sixth pivoting portion 462 of the second link 44 is then engaged with the second pivoting groove 264 of the second inner wall 262 of the second pivoting portion 26 of the key base 20, so that the first The assembly between the two connecting rods 44 and the key base 20 is such that the second connecting rod 44 can be pivoted relative to the key base 20 with the sixth pivot joint portion 462 as an axis. As for the assembly between the first and second links 41 and 44, the first link 41 is engaged with the fifth pivot portion 461 of the second link 44 through the third pivot portion 431, so that the first, The second links 41 and 44 can be synchronously operated by using the pivotal relationship between them.

During the aforementioned assembly process, the first and second pivot holes 253 and 263 and the first and second pivot grooves 254 and 264 are arranged. On the one hand, the first and second pivot holes 253 and 263 can be used to avoid the first The second connecting rods 41 and 44 have accidentally loosened during the operation. On the other hand, the fourth connecting portion 432 and the first connecting portion 41 of the first connecting rod 41 can be respectively connected through the first and second pivot grooves 254 and 264. The sixth pivot joint portion 462 of the two connecting rods 44 provides a convenient assembly effect, and the first and second cut grooves 255 and 265 can be respectively used to increase the first and second pivot grooves 254 and 264 and the fourth and third pivot grooves 254 and 264, respectively. The elastic deformation margin of the six pivot joints 432 and 462 during engagement to reduce the difficulty in assembly.

As shown in Figures 2, 4 and 5, the periphery of the button 50 has four guide grooves 51 facing each other, one end of each guide groove 51 is adjacent to a second stopper 52, and the button 50 is sleeved by the guide groove 51. The first stopper portion 28 provided on the key base 20 enables the keys 50 to move stably and smoothly relative to the key base 20, and the key 50 is engaged with the first stopper portion of the key base 20 through the second stopper portion 52. 28 to prevent the keys 50 and the key base 20 from being separated from each other. In addition, the four corners of the button 50 are provided with two opposite first slots 53 and two opposite second slots 54. The buttons 50 are respectively engaged with the first link 41 through the first and second slots 53 and 54. The first clamping shaft 421 of the first main lever body 42 and the second clamping shaft 452 of the second main lever body 45 of the second link 44 enable the button 50 to simultaneously push the first and second couplings when being pressed.杆 41,44.

As shown in FIGS. 2 and 4, the interlocking elastic piece 60 is made of a metal material. The middle of the interlocking spring 60 has a pressing portion 61, which corresponds to the triggering portion 322 of the switch 32. The two ends of the interlocking spring 60 have a latching portion 62, and the two latching portions 62 are respectively disposed on the first A first through slot 422 of a link 41 and a second through slot 454 of the second link 44 are respectively engaged with the center of the first main rod body 42 of the first link 41 and the first link of the second link 44. The center of the two main lever bodies 45 enables the interlocking elastic piece 60 to move in synchronization with the first and second links 41 and 44.

As shown in FIGS. 2 and 4, the compressed elastic piece 70 is made of a metal material. Both ends of the compressed elastic piece 70 are respectively engaged with the elastic piece fixing portions 27 of the key base 20, so that the length direction of the compressed elastic piece 70 is perpendicular to the length direction of the interlocking elastic piece 60. In addition, the compressed elastic piece 70 has a compressed portion 71 The position of the pressed portion 71 is between the trigger portion 322 of the switch 32 and the pressing portion 61 of the linked elastic piece 60, so that the pressed portion 71 of the pressed elastic piece 70 is pushed up by the pressing portion 61 of the linked elastic piece 60. At this time, the trigger portion 322 of the switch 32 is touched.

As shown in FIGS. 2 and 7, the backlight module 80 includes a plurality of light sources 81, a diffusion film 82, a light guide plate 83, and a reflection sheet 84. The light source 81 is arranged side by side on the circuit board 31 and is located on one side of the key base 20. The diffusion film 82 is provided on one side of the key 50 toward the key base 20. The two sides of the light guide plate 83 are connected to the diffusion film 82 and the reflection, respectively. Tablet 84.

From the above structure, as shown in FIGS. 6 and 7, when the button 50 is pressed, the button 50 will first push the first main lever body 42 of the first link 41 and the second main lever body of the second link 44. 45, the first main lever body 42 of the first link 41 and the second main lever body 45 of the second link 44 are simultaneously pivoted toward the circuit board 31, and then the first main lever body of the first link 41 The second main rod body 45 of 42 and the second link 44 will further push the engaging portion 62 of the interlocking elastic piece 60, so that the pressing portion 61 of the interlocking elastic piece 60 pushes the pressing portion 71 of the compressed elastic piece 70. When the pressured portion 71 of 70 touches the trigger portion 322 of the switch 32, the electrical conduction is completed. At this time, the circuit board 31 will control the light source 81 to generate light, and the light generated by the light source 81 will pass through the reflection sheet 84 and the light guide plate. 83 and diffuser film 82 to achieve the effect of improving brightness and uniform distribution. After releasing the force on the button 50, the compressed elastic piece 70 will push the linkage elastic piece 60 by its own elastic restoring force, and then the linkage elastic piece 60 will cooperate with its own elastic restoring force to push the first master of the first link 41. The lever body 42 and the second main lever body 45 of the second link 44 enable the first and second links 41 and 44 to push the button 50 to the state before pressing.

It is worth mentioning here that the compressed elastic piece 70 is used to increase the feel of the button 50, so it can be omitted according to actual needs. If the compressed elastic piece 70 is not provided, it is used when the button 50 is pressed. The pressing portion 61 of the interlocking elastic piece 60 directly contacts the trigger portion 322 of the switch 32 to form electrical conduction.

On the other hand, if the pressed position of the button 50 is not in the center, but is biased toward the first link 41 or the second link 44, the first side lever 43 and the first link 41 of the first link 41 The second side rods 46 of the two links 44 are pivotally connected to each other, so through the application of the lever principle, as long as one of the first and second links 41 and 44 is pushed by the button 50, the first The other one of the second connecting rods 41 and 44 will still act together, so that the effect of force balance can be achieved.

To sum up, the key device 10 of the present invention utilizes the structural configuration of the first and second links 41 and 44 to not only simplify the assembly process, but also to complete electrical conduction smoothly regardless of the position of the key 50, and further To achieve the purpose of improving the accuracy of the action.

10‧‧‧ Button Device
12‧‧‧Fix
20‧‧‧button seat
21‧‧‧ end wall
22‧‧‧Zhou Bi
23‧‧‧Circuit board mounting section
24‧‧‧Terminal Block Mounting Slot
25‧‧‧First pivot joint
251‧‧‧First Facade
252‧‧‧First inner wall
253‧‧‧first pivot hole
254‧‧‧First pivot slot
255‧‧‧first trench
26‧‧‧Second pivot joint
261‧‧‧Second Facade
262‧‧‧Second Inner Wall
263‧‧‧Second pivot hole
264‧‧‧Second pivot groove
265‧‧‧Second Divide
27‧‧‧ shrapnel fixing part
28‧‧‧First stop
30‧‧‧Circuit Module
31‧‧‧Circuit Board
32‧‧‧Switch
322‧‧‧Trigger Department
33‧‧‧Terminal Block
40‧‧‧ connecting rod set
41‧‧‧First connecting rod
42‧‧‧The first main shaft
421‧‧‧The first card axis
422‧‧‧The first slot
43‧‧‧ the first side rod
431‧‧‧Third pivot joint
432‧‧‧Fourth pivot joint
44‧‧‧ second link
45‧‧‧Second main shaft
452‧‧‧Second Axis
454‧‧‧Second trough
46‧‧‧Second side rod
461‧‧‧Fifth pivot joint
462‧‧‧Sixth pivot
50‧‧‧ button
51‧‧‧Guide
52‧‧‧Second stop
53‧‧‧First card slot
54‧‧‧Second Card Slot
60‧‧‧Linked shrapnel
61‧‧‧Relief section
62‧‧‧Card Connection Department
70‧‧‧compressed shrapnel
71‧‧‧Pressed section
80‧‧‧ backlight module
81‧‧‧light source
82‧‧‧ diffuser
83‧‧‧light guide
84‧‧‧Reflector

FIG. 1 is an external perspective view of a key device of the present invention. FIG. 2 is an exploded perspective view of the key device of the present invention. FIG. 3 is a perspective view of a key pad provided by the key device of the present invention. FIG. 4 is a perspective view of some elements of the key device of the present invention, which mainly shows the structural relationship of the key base, the link group, the linked elastic sheet and the compressed elastic sheet. FIG. 5 is a partial cross-sectional view of the key device of the present invention, which mainly shows the structural relationship between the key and the key base. FIG. 6 is a cross-sectional view of a key device of the present invention, which mainly shows a state of a key before being pressed. Fig. 7 is similar to Fig. 6 and mainly shows the state of the keys after being pressed. FIG. 8 is another embodiment of the terminal base provided by the key device of the present invention.

20‧‧‧button seat

21‧‧‧ end wall

22‧‧‧Zhou Bi

23‧‧‧Circuit board mounting section

24‧‧‧Terminal Block Mounting Slot

25‧‧‧First pivot joint

26‧‧‧Second pivot joint

27‧‧‧ shrapnel fixing part

30‧‧‧Circuit Module

31‧‧‧Circuit Board

32‧‧‧Switch

322‧‧‧Trigger Department

33‧‧‧Terminal Block

40‧‧‧ connecting rod set

41‧‧‧First connecting rod

42‧‧‧The first main shaft

421‧‧‧The first card axis

422‧‧‧The first slot

43‧‧‧ the first side rod

431‧‧‧Third pivot joint

432‧‧‧Fourth pivot joint

44‧‧‧ second link

45‧‧‧Second main shaft

452‧‧‧Second Axis

454‧‧‧Second trough

46‧‧‧Second side rod

461‧‧‧Fifth pivot joint

462‧‧‧Sixth pivot

50‧‧‧ button

51‧‧‧Guide

52‧‧‧Second stop

53‧‧‧First card slot

54‧‧‧Second Card Slot

60‧‧‧Linked shrapnel

61‧‧‧Relief section

62‧‧‧Card Connection Department

70‧‧‧compressed shrapnel

71‧‧‧Pressed section

81‧‧‧light source

82‧‧‧ diffuser

83‧‧‧light guide

Claims (10)

An elevator key device includes: a key base having a circuit board mounting portion, two opposing first pivot portions and two opposing second pivot portions, and two opposite sides of the circuit board mounting portion are respectively provided There is a first pivoting portion and a second pivoting portion; a circuit module having a circuit board and a switch, the circuit board is provided on the circuit board mounting portion of the key base, and the switch is provided on the circuit board And has a trigger part; a link group having a first link and a second link opposite to the first link, the first link has two opposite third pivot portions and two opposite A fourth pivoting portion, the second link having two opposing fifth pivoting portions and two opposing sixth pivoting portions, a third pivoting portion of the first link and a fifth of the second link The pivot parts are pivotally connected to each other, the fourth pivot part of the first link and the sixth pivot part of the second link are pivotally connected to the first and second pivot parts of the key base, respectively; The key is displaceably disposed on the key base and is engaged with the first and second links of the link group, so that the key can be pressed by an external force. The first and second links of the link group are synchronously driven by pressing; and a linked elastic sheet, both ends of the linked elastic sheet are respectively connected to the first and second links, and the linked elastic sheet has a pressing force. The pressing portion corresponds to the trigger portion of the switch, so that the linked elastic piece can be driven by the first and second links to abut the trigger portion of the switch through the pressing portion. The key device for an elevator according to claim 1, wherein the first link has a first main rod body and two opposite first side rod bodies, and two ends of the first main rod body each have a first One end of each of the first side lever bodies is connected to one end of the first main lever body, and each of the first side lever bodies has the third and fourth pivot joint portions, and the third pivot joint portion is located on the first At the other end of the side lever body, the fourth pivotal portion is located between the first clamping shaft of the first main lever body and the third pivotal portion. The second link has a second main lever body and two opposite sides. A second side rod body, two ends of the second main rod body have a second clamping shaft, one end of each of the second side rod bodies is connected to one end of the second main rod body, and each of the second side rod body It has the fifth and sixth pivot joints, the fifth pivot joint is located at the other end of the second side rod body, the sixth pivot joint portion is located on the second clamping shaft of the second main rod body and the fifth pivot Between the connecting parts; the key has two opposite first engaging slots and two opposite second engaging slots, and the two first engaging slots are respectively engaged with the first engaging shaft of the first main rod body of the first link , The The two second clamping slots are respectively engaged with the second clamping shaft of the second main rod body of the second link; both ends of the linked elastic piece are respectively engaged with the center of the first main rod body of the first link and The center of the second main rod body of the second link. The key device for an elevator according to claim 2, wherein the center of the first main rod body of the first link has a first through slot, and the center of the second main rod body of the second link has a first Two through slots, two ends of the linked elastic sheet are respectively inserted in the first and second through slots. The key device for an elevator according to claim 1, wherein the key base further has two opposite elastic piece fixing parts, and the key device further includes a compressed elastic piece, and the length direction of the compressed elastic piece is perpendicular to the length of the linked elastic piece. In the direction, two ends of the compressed elastic piece are respectively engaged with one of the elastic piece fixing portions of the key base, and the compressed elastic piece has a compressed portion which is located between the trigger portion of the switch and the linked elastic piece. Between the pressure parts. The key device for an elevator according to claim 1, wherein the first pivot joint portion of the key base has a first outer wall and a first inner wall, the first outer wall has a first pivot hole, and the first An inner upright wall has a first pivot groove, a fourth pivotal connection portion of the first link is a convex shaft, and one end of the fourth pivotal connection portion is pivotably passed through the first pivotal portion of the first outer upright wall. In the hole, the other end of the fourth pivotal portion is pivotably engaged in a first pivot groove of the first inner upright wall, and the second pivotal portion of the key base has a second outer upright wall and a second An inner vertical wall, the second outer vertical wall has a second pivot hole, the second inner vertical wall has a second pivot slot, the sixth pivot joint portion of the second link is a convex shaft, and the sixth pivot joint portion One end is pivotably passed through the second pivot hole of the second outer wall of the key base, and the other end of the sixth pivot part is pivotally engaged with the second of the second inner wall of the key base. Inside the pivot groove. The key device for an elevator according to claim 5, wherein the first inner wall of the first pivot joint portion of the key base has a first cut groove communicating with the first pivot groove, and the second pivot joint of the key base The second inner vertical wall of the part has a second cut groove communicating with the second pivot groove. The key device for an elevator according to claim 1, wherein the third pivotal portion of the first link is a convex shaft, and the fifth pivotal portion of the second link is a groove. The key device for an elevator according to claim 1, wherein the key base further has a terminal base mounting groove adjacent to the circuit board mounting portion, and the circuit module further has a terminal base, which is provided in the terminal base. The terminal block is installed in the terminal block mounting slot and connected to the circuit board. The key device for an elevator according to claim 1, further comprising a backlight module, the backlight module has a light source, a diffusion film, a light guide plate, and a reflective sheet, and the light source is disposed on the circuit board and located on the circuit board. One side of the key base, the diffusion film is disposed on one side of the key facing the key base, one side of the light guide plate is connected to the diffusion film, and the other side of the light guide plate is connected to the reflection sheet. The button device for an elevator according to claim 1, wherein the button seat has two opposite first stop portions, the button has two opposite guide grooves and two opposite second stop portions, and each of the guide grooves is adjacent At a second stopper portion, the guide groove of the button is movably sleeved to the first stopper portion of the key base, and the second stopper portion of the key is abutted against the first stopper portion of the key base. .