CN114512362A

CN114512362A - Key assembly and supporting mechanism for key

Info

Publication number: CN114512362A
Application number: CN202111400897.3A
Authority: CN
Inventors: 张立德; 陈志宏; 陈彦廷
Original assignee: Huaian Darfon Electronics Co ltd; Darfon Electronics Corp
Current assignee: Huaian Darfon Electronics Co ltd; Darfon Electronics Corp
Priority date: 2021-04-07
Filing date: 2021-11-24
Publication date: 2022-05-17
Also published as: TWI800949B; CN217035486U; TW202240616A

Abstract

The invention discloses a key assembly which comprises a switch module, a supporting mechanism and a shielding mechanism. The switch module has a substrate and a pair of signal generator and signal sensor. The signal generator and the signal sensor are arranged on the substrate, the signal generator provides sensing signals for the signal sensor, and the signal sensor receives the sensing signals to obtain corresponding sensing strength. The supporting mechanism is arranged on the top surface, and the top of the supporting mechanism moves up and down in response to the pressing force. The shielding mechanism comprises a pivoting part, a connecting sheet and a blocking sheet. The pivot part is rotatably arranged on the top surface, the connecting sheet extends to the pivot part, and the connecting sheet is movably connected to the supporting mechanism and swings up and down relative to the base plate along with the movement of the top part. The blocking piece extends to the pivoting part and is driven by the connecting piece to be inserted into or separated from a gap between the signal generator and the signal sensor so as to change the sensing strength.

Description

Key assembly and supporting mechanism for key

Technical Field

The present invention relates to a key, and more particularly, to a key assembly and a supporting mechanism for the key.

Background

Membrane switch keys and mechanical keys are the types of keys commonly used in conventional keyboards. The main difference between the membrane switch key and the mechanical key is that the circuit structure for generating signals is different. Generally, a membrane switch key is a switch element using a membrane circuit layer as a signal generation, when a key cap is pressed to trigger the membrane circuit layer, an upper circuit layer is deformed to make a switch contact of the upper circuit layer contact a corresponding switch contact of a lower circuit layer, and then the membrane switch is turned on to generate a signal. However, the thin film circuit layer is easily damaged by frequent use or improper force application, and is difficult to maintain, and when a user presses the key cap to trigger the thin film circuit layer, clear step feedback is lacked, so that the pressing hand feeling is not good, and the manipulation feeling of the user cannot be satisfied.

The mechanical key is a switch element which uses the conduction of the metal sheet and the metal contact as the signal generation. However, the metal sheet and the metal contact are easily abraded by impact to affect the service life of the key, and the metal sheet or the metal contact is corroded by moisture to cause bad conduction and affect the stability of the key. Furthermore, the conventional mechanical key is not suitable for being applied to a portable electronic device with a high requirement for thinning, such as a notebook computer, because the structure is complicated and the volume is large.

Disclosure of Invention

In view of the problems in the prior art, the present invention provides a key assembly and a supporting mechanism for a key to solve the above problems.

Therefore, the technical problem to be solved by the present invention is to provide a key assembly, which comprises:

a switch module having a substrate and a pair of a signal generator and a signal sensor; the signal generator and the signal sensor are arranged on the substrate, the signal generator provides sensing signals for the signal sensor, and the signal sensor receives the sensing signals to obtain corresponding sensing strength;

a supporting mechanism arranged on the top surface of the substrate, wherein the top of the supporting mechanism moves up and down in response to the pressing force; and

a shielding mechanism comprising:

the pivoting part is rotatably arranged on the top surface;

the connecting sheet extends to the pivoting part and is movably connected to the supporting mechanism to swing up and down relative to the base plate along with the movement of the top part; and

the blocking piece extends to the pivoting part and is driven by the connecting piece to be inserted into or separated from a gap between the signal generator and the signal sensor so as to change the sensing strength.

As an optional technical solution, the supporting mechanism includes:

two supports, each support has a bottom plate end and a keycap end, each bottom plate end is movably connected with the base plate, and the two supports are unfolded outwards to make the two keycap ends far away from each other, and the two keycap ends form the top of the supporting mechanism; and

the elastic piece is connected with the two keycap ends;

the signal generator and the signal sensor are positioned between the projections of the two keycap ends on the top surface, the connecting sheet is movably connected to one of the two keycap ends, and the rotating axial direction of the pivoting part is parallel to the rotating axial directions of the two supports.

Alternatively, one of the two keycap ends is provided with a receptacle, and the connecting piece is slidably inserted into the receptacle.

As an alternative solution, the connecting sheet is a longitudinal sheet body configured to be perpendicular to the top surface, and the end of the connecting sheet is provided with an open slot hole, one of the two keycap ends is provided with a guiding sheet, the guiding sheet is used for being inserted into the open slot hole, and the width of the open slot hole is larger than the thickness of the guiding sheet.

As an optional technical solution, the key assembly further includes a key cap disposed at the top of the supporting mechanism to be located above the top surface by being supported by the supporting mechanism, and the supporting mechanism supports the key cap to move up and down relative to the substrate.

As an optional technical solution, the key assembly further includes a backlight light source disposed on the top surface, and the backlight light source is configured to project illumination light toward the keycap.

As an optional technical solution, the key assembly further includes a diffusion sheet, which is combined with the top surface and covers the backlight source.

As an optional technical solution, the substrate has a slot, one of the signal generator and the signal sensor and the backlight source are located on different sides of the substrate, and the front end of the blocking sheet is used for passing through the slot to be inserted into or separated from a gap between the signal generator and the signal sensor.

Alternatively, the signal generator and the signal sensor are a combination of a light receiver and a light emitter, or the signal generator and the signal sensor are a combination of a magnet and a hall sensor.

As an optional technical solution, the signal generator and the signal sensor are arranged along a signal transmission direction, and the signal transmission direction is perpendicular to a rotation axis of the pivot joint.

As an optional technical solution, the blocking piece and the connecting piece are located at two sides or the same side of the pivoting part in the axial direction of the rotation.

As an optional technical solution, the shielding mechanism further includes two pivoting tabs, the two pivoting tabs respectively extend to two opposite sides of the pivoting portion, and the two pivoting tabs are axially disposed along a rotation axis of the pivoting portion.

As an optional technical solution, the key assembly further includes a shielding element, the shielding element is disposed on the top surface, and the shielding element has a window; the shielding element surrounds the signal generator and the signal sensor, and the blocking piece penetrates through the window.

The present invention also provides a supporting mechanism for a key, wherein the supporting mechanism for a key comprises:

a substrate having a top surface; and

two supports, each support has a bottom plate end and a keycap end, each bottom plate end is movably connected with the substrate, and the two supports are unfolded outwards to make the two keycap ends far away from each other; each bracket is also provided with a body and a side arm part, the side arm part extends to the corresponding body, each body respectively forms each keycap end, and the tail end of each side arm part respectively forms each bottom plate end correspondingly;

the front end of each side arm is respectively provided with a lower pressing piece and a catching piece, the lower pressing piece and the catching piece extend outwards along a long axis direction of each side arm, and relative to the base plate, the lower pressing piece of one of the two brackets is positioned above the catching piece of the other one of the two brackets.

As an optional technical solution, the pressing piece and the capturing piece are bent towards the substrate, the front end of the capturing piece is provided with a capturing part bent towards a direction away from the substrate, and a bending angle is formed between the capturing part and the capturing piece.

As an optional technical solution, the bending angle of the catching sheet is greater than the bending angle of the lower pressing sheet, and the length of the lower pressing sheet is greater than the length of the catching sheet.

As an alternative solution, the lower pressing sheet is perpendicular to the substrate, and the capturing sheet is perpendicular to the lower pressing sheet.

As an optional technical solution, the front end of the lower side edge of the lower pressing sheet is in a shape extending and protruding towards the substrate; the catching piece is bent and then bent towards the front to form a catching part bent towards the front, and the lower edge of the lower pressing piece is used for contacting the catching part.

As an optional technical solution, the lower pressing piece extends outwards along the long axis direction of the side arm part, and the lateral extension of the lower pressing piece forms an extension part, and the end of the extension part is provided with the catching piece which is bent towards the base plate and extends forwards.

Compared with the prior art, the key assembly of the invention utilizes the supporting mechanism to drive the shielding mechanism, changes the shielding degree of the sensing signal as the switching signal, achieves the conversion of the pressing signal quickly and accurately, and can be applied to various key structures to be suitable for portable electronic devices. In addition, the first support and the second support of the supporting mechanism are mutually linked through the linkage of the linkage mechanism, so that the first support, the second support and the keycap can be really linked, the movement of the shielding mechanism is really linked with the movement of the keycap, and the condition that the keycap is pressed cannot be correctly detected is effectively avoided.

The invention is described in detail below with reference to the drawings and specific examples, but the invention is not limited thereto.

Drawings

FIG. 1 is a partially exploded view of a key assembly according to a first embodiment of the present invention.

Fig. 2 is an exploded view of a part of the elements in the first embodiment of the present invention.

Fig. 3 is a schematic perspective view of a switch module, a shielding mechanism and a backlight source according to a first embodiment of the invention.

Fig. 4 is a top view of the switch module and the backlight source according to the first embodiment of the invention.

Fig. 5 is a perspective view of the bottom plate and two brackets in the first embodiment of the present invention.

Fig. 6 is a perspective view of two brackets, a shielding mechanism and a shielding element according to a first embodiment of the present invention.

FIG. 7 and FIG. 8 are side views of the switch module, two brackets and the shielding mechanism according to the first embodiment of the present invention.

Fig. 9 and fig. 10 are side views of the backlight source, the switch module, two brackets and the shielding mechanism according to a variation of the first embodiment of the present invention.

Fig. 11 is a side view of the backlight source, the switch module, two brackets and the shielding mechanism in another variation of the first embodiment of the invention.

Fig. 12 is a partially enlarged and exploded view of the interlocking mechanism according to the first embodiment of the present invention.

Fig. 13 is a partially enlarged schematic view of the interlocking mechanism according to the first embodiment of the present invention.

FIG. 14 is a partially exploded view of a key assembly according to a second embodiment of the present invention.

FIG. 15 is a perspective view of the bottom plate, two brackets and the shielding mechanism according to the second embodiment of the present invention.

FIG. 16 and FIG. 17 are side views of a switch module, two brackets and a shielding mechanism according to a second embodiment of the present invention.

FIG. 18 is a partially enlarged and exploded view of the interlocking mechanism according to the third embodiment of the present invention.

Fig. 19 is a partially enlarged schematic view of an interlocking mechanism according to a third embodiment of the present invention.

FIG. 20 is a partially enlarged and exploded view of the interlocking mechanism according to the fourth embodiment of the present invention.

Fig. 21 is a partially enlarged schematic view of an interlocking mechanism according to a fourth embodiment of the present invention.

Detailed Description

In order to further understand the objects, structures, features and functions of the present invention, the following embodiments are described in detail.

Please refer to fig. 1 and 2, which illustrate a key assembly according to an embodiment of the present invention, which can be applied to any pressing input device (e.g., a keyboard) or integrated into any suitable electronic device (e.g., a key of a portable electronic device or a keyboard of a notebook computer) to provide a fast and precise triggering function. The key assembly is suitable for various key structure designs and improves the maintenance feasibility. The structure and operation of the key assembly of each embodiment will be described in detail with reference to the drawings.

Referring to fig. 1 and fig. 2, the key assembly includes a switch module 607, a key cap 604, a supporting mechanism, an elastic member 605, a shielding mechanism 670, and a backlight 643.

As shown in fig. 1, 2, 3 and 4, the switch module 607 has a substrate 648 and a pair of signal generators and signal sensors. The signal generator is used for providing a sensing signal, and the signal sensor is used for receiving the sensing signal to obtain corresponding sensing intensity. In the examples presented in the following description, the signal generator is the optical transmitter 641, the signal sensor is the optical receiver 642, and the sensing signal is an optical signal, thereby constituting an optical switch; the present invention does not preclude the use of magnetic switches. In the following description, the relative positional relationship between the signal generator (light emitter 641) and the signal sensor (light receiver 642) may be interchanged. The present invention is not limited to a straight traveling optical path, and can also realize an optical switching function by a refracted or reflected meandering optical path.

As shown in fig. 2, 3 and 4, the substrate 648 has a top surface 648a and a bottom surface 648b, the light emitter 641 and the light receiver 642 are respectively disposed on the top surface 648a of the substrate 648, and a fixed gap is maintained between the light emitter 641 and the light receiver 642. The optical transmitter 641 and the optical receiver 642 are connected to a processing circuit (not shown) through a substrate 648 to form a switch for generating a trigger event. In one embodiment, the substrate 648 is a circuit board, and the light emitter 641 and the light receiver 642 are electrically connected to the circuit board (i.e., the substrate 648) and further connected to the processing circuit. In various embodiments, the substrate 648 is a plate without signal transmission function, the light emitter 641 and the light receiver 642 are electrically connected to the flexible printed circuit board, and the flexible printed circuit board is fixed on the top surface 648a of the substrate 648, so as to indirectly dispose the light emitter 641 and the light receiver 642 on the top surface 648a of the substrate 648.

Referring to fig. 3 and 4, in the first embodiment, the sensing signal S is a specific wavelength light, such as infrared light. The light emitter 641 projects light of a specific wavelength toward the light receiver 642 as a sensing signal, and the light receiver 642 receives the light of the specific wavelength to produce a corresponding sensing intensity. Generally, the light receiver 642 receives light to generate a corresponding voltage signal, and thus the sensing intensity may be a voltage value of the voltage signal generated after the light receiver 642 receives light with a specific wavelength.

In various embodiments, the signal generator and the signal sensor are a magnet and a hall sensor, respectively. The magnet is used for generating a magnetic field as a sensing signal, and the hall sensor senses the existence and strength of the magnetic field by using the hall effect to obtain sensing strength. The output voltage of the hall sensor is proportional to the magnetic field strength, and thus the sensing strength may be a voltage value of a voltage signal output after the hall sensor senses the magnetic field.

As shown in fig. 1 and 4, the key cap 604 is supported by the supporting mechanism to be located above the top surface 648a, and a light emitting area (not shown) may be disposed on the key cap 604. The light-emitting area may be a hollow-out area, and the hollow-out area may be filled with or not filled with a light-transmitting material. Alternatively, the key cap 604 can be made of a transparent material and coated with an opaque coating to leave the light-emitting area without coating. The supporting mechanism, the shielding mechanism 670 and the backlight light source 643 are substantially located in the key cap projection area 604a of the substrate 648 of the key cap 604, and the position of the backlight light source 643 corresponds to the light emitting area. The supporting mechanism can move in response to the pressing force, and particularly the top of the supporting mechanism moves up and down in response to the pressing force. The key cap 604 is disposed on the top of the supporting mechanism, and the upper surface of the key cap 604 is used for receiving an externally applied pressing force. The key cap 604 transmits a pressing force to the top of the support mechanism, so that the top of the support mechanism moves in response to the pressing force and supports the key cap 604 to move up and down with respect to the base plate 648.

As shown in fig. 1 and fig. 2, specifically, the supporting mechanism includes a first bracket 601 and a second bracket 602. The first frame 601 and the second frame 602 each have a bottom end and a key cap end, specifically, the first frame 601 has a bottom end 6012 and a key cap end 6014, the second frame 602 has a bottom end 6022 and a key cap end 6024, and the

bottom end

6012,6022 is movably connected to the top surface 648a of the substrate 648. The key cap ends 6014,6024 form the top of the support mechanism, and the first and second supports 601,602 are spread outwardly to move the two key cap ends 6014,6024 away from each other. The key cap end 6014 of the first support 601 and the key cap end 6024 of the second support 602 are movably connected to the key cap 604, so that the key cap 604 is supported on top of the supporting mechanism and can transmit a pressing force to the two key cap ends 6014,6024. On top surface 648a of substrate 648, light emitter 641 and light receiver 642 are located between the projections of two keycap ends 6014,6024 on top surface 648 a.

As shown in fig. 1 and 2, the elastic member 605 may be a tension spring or other element (e.g., a wire made of elastic material) providing tension. The elastic member 605 is laterally connected to the supporting mechanism, for example, the elastic member 605 is connected to the two keycap ends 6014,6024, and provides a pulling force between the two keycap ends 6014,6024, which makes the two keycap ends 6014,6024 approach each other and move upward, i.e. makes the first support 601 and the second support 602 swing upward, and makes the top of the supporting mechanism move upward. In addition, the present invention does not exclude the two ends of the elastic element 605 being connected to the other parts of the first support 601 and the second support 602, as long as the connection of the elastic element 605 can make the first support 601 and the second support 602 swing upward to bring the two keycap ends 6014,6024 close to each other and move upward, so that the top surface 648a of the supporting mechanism moves upward to form a restoring force pushing the keycap 604 upward.

As shown in fig. 1 and 2, specifically, each of the first bracket 601 and the second bracket 602 includes a bracket body and two side arm portions. That is, the first bracket 601 includes a bracket body 613 and two side arm portions 611/612, and the second bracket 602 includes a bracket body 623 and two side arm portions 621/622). In the first bracket 601, two side arm portions 611/612 extend from both ends of the bracket body 613 and are movably connected to the top surface 648a of the base plate 648; and/or the second bracket 602, two side arm portions 621,622 extend from two ends of the bracket body 623 and are movably connected to the top surface 648a of the base plate 648. The support body 613,623 is perpendicular to the connection direction of the elastic element 605, and the elastic element 605 is connected to the two support bodies 613,623, so that the two support bodies 613,623 are normally provided with a pulling force to make the two support bodies 613,623 approach each other, and a restoring force pushing the keycap 604 upwards is formed. The holder body 613 of the first holder 601 (specifically, an upper portion thereof) constitutes a key cap end 6014 of the first holder 601, the holder body 623 of the second holder 602 (specifically, an upper portion thereof) constitutes a key cap end 6024 of the second holder 602, and the ends of the side arm portions 611,612 constitute a bottom plate end 6012 of the first holder 601, and the ends of the side arm portions 621,622 constitute a bottom plate end 6022 of the second holder 602.

As shown in fig. 2, 3, 4 and 5, the supporting mechanism further includes a bottom plate 603, and the bottom plate 603 is coupled to a top surface 648a of the substrate 648. The base plate 603 has connectors 631,632, the connectors 631,632 may be hook and loop connectors at both ends of the plate, and the plate is integrally formed with the base plate 603 and protrudes away from the base plate 648. The panels may be arranged in pairs and parallel to each other such that each pair of corresponding hooks forms a connector 631,632. Each

bottom panel end

6012,6022 is movably connected to a respective connector 631,632 and thereby to bottom panel 603. Meanwhile, the key cap ends 6014,6024 are respectively and movably coupled to the key caps 604, thereby forming a butterfly wing type supporting mechanism for stably supporting the key caps 604 to move up and down relative to the substrate 648. If the one-piece base 603 is not provided and the connector 631,632 can be directly secured to the top surface 648a of the base plate 648, the base ends 6012,6022 of the first bracket 601 and the second bracket 602 can be movably connected to the connectors 631,632 of the top surface 648 a. It is not excluded to omit the bottom plate 603 and to have the

bottom plate end

6012,6022 directly pivotally connected to the circuit board 644. The first bracket 601 and the second bracket 602 may be arranged in a cross configuration and pivoted to each other, and may be arranged in a scissors configuration.

As shown in fig. 1, in particular, the key cap 604 may be an injection molded rectangular cap, for example, and the lower surface of the key cap 604 is provided with a

coupling member

6042,6044 for coupling with the support mechanism. The

coupling members

6042,6044 can be a coupling member 6042 having a shaft hole and a coupling member 6044 having a slide groove, respectively; alternatively, the

coupling members

6042,6044 are all coupling structures having sliding grooves. The key cap ends 6014,60242 of the first and

second supports

601 and 602 are respectively movably connected to the

coupling members

6042,6044 of the key cap 604, and at least one of the key cap ends 6014,6024 is slidable relative to the corresponding

coupling member

6042,6044, such that the

key cap end

6014,6024 is movably connected to the key cap 604, and the key cap 604 can transmit a pressing force to the

key cap end

6014,6024.

As shown in fig. 2, 3 and 6, the shielding mechanism 670 includes a pivot portion 671, a connecting piece 672 and a blocking piece 650. The pivot 671 is rotatably disposed on the top surface 648a of the substrate 648. Substantially, the rotation axis of the pivot 671, the rotation axis of the first bracket 601 and the rotation axis of the second bracket 602 are parallel to each other.

As shown in fig. 2, 3 and 6, the connecting piece 672 extends at the pivot portion 671, and the connecting piece 672 is directly or indirectly connected to the supporting mechanism in a movable state, so that the connecting piece 672 swings up/down relative to the substrate 648 along with the movement of the top and the keycap 604. The blocking piece 650 extends to the pivot portion 671 to be driven by the connecting piece 672 to be inserted into or separated from the gap between the optical transmitter 641 and the optical receiver 642, so as to change the magnitude of the sensing intensity.

Specifically, when the signal generator and the signal sensor are a combination of the light emitter 641 and the light receiver 642, the shielding mechanism 670 is made of a non-light-tight material, and particularly can shield the material with a specific wavelength. Alternatively, the surface of the shielding mechanism 670 may be coated with a light-impermeable material so that the shielding mechanism 670 is entirely light-impermeable.

When the signal generator and the signal sensor are a combination of a magnet and a hall sensor to form a magnetic switch, at least the blocking piece 650 is doped with a material having magnetic permeability (such as iron, cobalt, nickel or an alloy thereof), or the blocking piece 650 is made of iron, cobalt, nickel or an alloy thereof having magnetic permeability. It is not excluded that the shielding mechanism 670 is integrally made of a material having magnetic permeability, for example, a sheet of iron, cobalt, nickel or an alloy thereof is directly punched to make the shielding mechanism 670.

In the first embodiment, as shown in FIG. 6, connecting sheet 672 is movably connected to one of keycap ends 6014,6024 of first support 601 and second support 602. Connecting piece 672 is shown as being movably connected to keycap end 6014 of first frame 601 for illustration. It should be noted that the first and second are only used for distinguishing different elements, and do not necessarily indicate that the elements are different in structure. The first support 601 and the second support 602 may be identical elements, and thus the connection piece 672 is connected to the key cap end 6014 of the first support 601 or the key cap end 6024 of the second support 602 without indicating a change in the substantial connection relationship.

As shown in fig. 6, in the first embodiment, a holder body 613 as a keycap end 6014 is provided with an insertion hole 613a, and a connecting piece 672 is slidably inserted into the insertion hole 613a to be movably attached to the holder body 613. In the process of swinging the first bracket 601, besides swinging along with the up-and-down movement of the key cap end 6014, the connecting sheet 672 can still slide relative to the key cap end 6014, so that the connecting sheet 672 cannot block the key cap end 6014 to cause the first bracket 601 to be unable to swing. The first frame 601 can be replaced by a second frame 602, that is, the insertion hole 613a is located in the frame body 614 of the second frame 602, and the connecting piece 672 is movably connected to the key cap end 6024 of the second frame 602. In one or more embodiments, first support 601 is substantially identical to second support 602, and thus connecting sheet 672 may optionally be connected to one of keycap ends 6014,6024 of first support 601 and second support 602.

Specifically, the signal generator and the signal sensor, such as the light emitter 641 and the light receiver 642, are arranged along a signal transmission direction perpendicular to the rotation axis of the pivot portion 671. The location of the signal generator and signal sensor is generally between the projections of keycap ends 6014,6024 on top surface 648 a. The projection of the arrangement direction of the blocking piece 650, the pivot portion 671 and the connecting piece 672 on the substrate 648 is parallel to the signal transmission direction. The invention does not exclude the zigzag signal transmission path formed by refraction and reflection, and the signal transmission path is not limited by the straight line along the signal transmission direction.

As shown in fig. 2, 3 and 6, the shielding mechanism 670 further includes two pivoting tabs 673 extending to two opposite sides of the pivoting portion 671. The pivot tab 673 is configured to rotatably dispose the pivot portion 671 on the top surface 648a along the rotation axis of the pivot portion 671. The catch 650 and the link 672 are located on both sides of the pivot 671 in the rotational axis direction, that is, the catch 650 and the link 672 extend substantially in opposite directions. The optical receiver 642 as a signal sensor may be located between the two pivoting tabs 673, that is, the two pivoting tabs 673 are located at two sides of the signal transmission direction, and the pivoting portion 671 is located above the optical receiver 642. Therefore, the pivot portion 671 and the two pivot tabs 673 can cover the signal sensor, so as to reduce the interference of the external signal to the signal sensor. Taking the optical receiver 642 as an example, the pivot portion 671 and the two pivot tabs 673 can block external light from above the pivot portion 671 and outside the two pivot tabs 673, so as to prevent the external light from interfering with the acquisition of the sensing intensity of the optical receiver 642. For example, when the signal sensor is a hall sensor, the pivot connection portion 671 and the two pivot connection tabs 673, which comprise magnetic conductive materials, can provide magnetic field shielding to reduce the interference of external electromagnetic fields on the hall sensor.

It should be noted that in the embodiments of the present invention, the positions of the signal generator and the signal sensor can be switched, that is, the pivoting portion 671 and the two pivoting tabs 673 can cover the signal generator. In this case, the external device such as the shielding device 680 (described later) can be used to reduce the interference from the outside to the signal sensor. In this case, the cover covers the pivot portion 671 and the two pivot tabs 673 of the signal generator, so as to reduce the interference of the signal generator with the peripheral devices; for example, when the signal generator is a magnet, the pivot portion 671 and the two pivot tabs 673 can reduce the interference of the magnet with external devices.

As shown in fig. 2, 3 and 4, the backlight 643 is disposed on the top surface 648a of the substrate 648 for projecting illumination light toward the key cap 604. When the substrate 648 is a circuit board, the backlight 643 is electrically connected to the substrate 648, and receives power through the substrate 648. When the substrate 648 does not have a circuit, the backlight 643 can receive power through a flexible circuit board or a wire. Specifically, the switch module 607, the supporting mechanism, the shielding mechanism 670 and the backlight 643 are all located within the projection of the key cap 604 on the substrate 648. Therefore, when the key assembly is viewed from above, the key cap 604 can fully cover the switch module 607, the supporting mechanism, the shielding mechanism 670 and the backlight 643. The light emergent area of the keycap 604 is used for illumination light to pass through, and the upper surface of the keycap 604 is illuminated; preferably, the position of the backlight 643 on the top surface 648a corresponds to the light emitting area.

As shown in fig. 1, 2 and 6, in order to further reduce the interference to the signal sensor, the key assembly further includes a shielding element 680 directly or indirectly disposed on the top surface 648a, the shielding element 680 having a window 681, and the shielding element 680 surrounding the light emitter 641 and the light receiver 642. The shutter 650 may be inserted into the gap between the optical transmitter 641 and the optical receiver 642 through the window 681 to intercept the sensing signal. The pivoting tabs 673 are pivoted to the pivoting posts 682 of the shielding element 680 such that the pivoting tabs 673 are indirectly pivoted to the top surface 648 a. In various embodiments, the pivot post 682 may be separate from the shield member 680 and disposed on the top surface 648 a.

As shown in fig. 1 and 2, the key assembly further includes a diffusion sheet 661. The diffusion sheet 661 is directly or indirectly coupled to the top surface 648a of the substrate 648, and the diffusion sheet 661 covers the backlight light source 643 and is positioned between the backlight light source 643 and the key caps 604. The illumination light emitted from the backlight 643 can be widely irradiated onto the inner surface of the key cap 604 through the diffusion sheet 661. In addition, the side walls for disposing the diffusion sheet 661 can be made of a light-shielding material to reduce light emission in the horizontal direction. When the signal sensor is the light receiver 642, the diffusion sheet 661 can prevent the illumination light from interfering with the sensing intensity obtained by the light receiver 642.

As shown in fig. 1 and 2, the shielding member 680 and the diffusion sheet 661 may be directly coupled to the bottom plate 603, and thus indirectly coupled to the top surface 648a through the bottom plate 603. The base plate 603 is provided with first fasteners 691, and the shielding member 680 and the diffusion plate 661 are respectively provided with second fasteners 692. The first fasteners 691 and the second fasteners 692 are matched to fix the shielding element 680 and the diffusion plate 661 to the bottom plate 603. For example, as shown in the figure, the second fasteners 692 of the diffusion plate 661 are convex pillars, and the corresponding first fasteners 691 are lugs protruding from the bottom plate 603 and having holes; for another example, the second fasteners 692 of the shielding element 680 include posts and hook holes, and the corresponding first fasteners 691 are respectively lugs having holes and hooks protruding from the bottom plate 603.

As shown in fig. 4 and 5, the elastic member 605 is shown by a dotted line. The elastic member 605 transversely connects the key cap ends 6014,6024 of the first and

second supports

601 and 602 along a connecting direction, and the orthographic projection of the elastic member 605 divides the key cap projection area 604a of the key cap 604 on the top surface 648a of the substrate 648 into a first area 604a1 and a second area 604a 2. The signal generator (light emitter 641) and the signal sensor (light receiver 642) are disposed in the first region 604a1, and the backlight 643 is disposed in the second region 604a 2. The obstruction and reflection of the elastic member 605 can reduce the intensity of the illumination light in the second region 604a2, thereby reducing the interference of the illumination light with the optical signal sensor (the optical receiver 642). When the signal generator and the signal sensor are a combination of a magnet and a hall sensor to form a magnetic switch, the elastic member 605 may be made of a magnetic conductive material (e.g., iron, cobalt, nickel, or an alloy thereof) to block a magnetic field, so as to prevent the hall sensor from being interfered by a magnetic field change generated by the backlight light source 643 during switching and lighting.

As shown in fig. 1, 2, 3 and 4, the base plate 603 has a claw portion 693 protruding toward the base plate 648, and the base plate 648 has a corresponding fixing hole 694. The claw portions 693 can be inserted into and fastened to the edges of the fixing holes 694, thereby fixing the bottom plate 603 to the top surface 648a of the base plate 648. The supporting mechanism, the shielding mechanism 670, the shielding member 680, and the diffusion sheet 661 may be previously combined as a subassembly based on the detachable base plate 603. Positioning of the subassembly, particularly the positioning of the tabs 650 relative to the signal generators and sensors, is accomplished by positioning the base 603 to the base 648 via the attachment holes 694. The key cap 604 may be mounted to the sub-assembly first, or the key cap 604 may be mounted to the sub-assembly after the sub-assembly is secured. In fact, the bottom plate 603 only needs to occupy a small area on the substrate 648, and the supporting mechanism, the shielding mechanism 670, the shielding element 680 and the diffusion sheet 661 can be mounted thereon, and each key assembly can be provided with a separate bottom plate 603, but it is not excluded that the bottom plates 603 of a plurality of key assemblies are connected to each other to form a single bottom plate with a large area.

Referring to fig. 7 and 8, fig. 7 and 8 are side views of a switch module, two brackets and a shielding mechanism according to a first embodiment of the invention. Fig. 7 and 8 are simplified, and only the substrate 648, the light emitter 641, the light receiver 642, the first bracket 601, the second bracket 602, and the shielding mechanism 670 are remained. As shown, the projection of the dummy bar 650 on the substrate 648 is located approximately between the light emitter 641 and the light receiver 642, and one of the light emitter 641 and the light receiver 64 is located between the dummy bar 650 and the projection of the connecting sheet 672 on the substrate 648. The shutter mechanism 670 rotates about its rotational axis in a direction perpendicular to the top surface 648a of the base plate 648, with the flap 650 moving in a direction opposite to the linear movement of the link plate 672. In addition, the front end of the flap 650 may be bent toward the base plate 648 to shorten the distance between the front end of the flap 650 and the top surface 648 a.

Fig. 7 shows the key cap 604 (the key cap 604 is not shown) not pressed, and the pulling force provided by the elastic member 605 makes the two key cap ends 6014,6024 approach each other and move upward, so as to move the key cap 604 upward to the highest point that can be reached in this embodiment. At this time, like a seesaw, the portion of the connecting piece 672 connected to the key cap end 6014 moves upward, and the front end of the blocking piece 650 is driven to move downward to the lowest point in the opposite direction, and the front end of the blocking piece 650 is inserted into the gap between the light emitter 641 and the light receiver 642. The front end of the blocking piece 650 blocks the transmission of the sensing signal. At this time, the sensed intensity obtained by the signal sensor, the light receiver 642 is the first intensity. The first intensity will typically be the minimum sensed intensity in the first embodiment; however, the value of the first intensity is not necessarily equal to zero, because when the key cap 604 is at the highest point and the barrier 650 is at the lowest point, the transmission of the sensing signal is not necessarily completely interrupted by the barrier 650.

Fig. 8 shows a state where the key cap 604 (the key cap 604 is not shown) is pressed to the lowest point, and the key cap 604 is pressed to move downward to transmit the pressing force to the two key cap ends 6014,6024, and to bring the two key cap ends 6014,6024 to move downward to the lowest point. The two key cap ends 6014,6024 move downward and away from each other, so that the elastic member 605 is stretched to generate an elastic restoring force, which is a pulling force. At the same time, the portion of the connecting piece 672 connected to the key cap end 6014 moves downward, and drives the front end of the blocking piece 650 to move upward reversely to the highest point that can be reached in this embodiment. The front end of the blocking piece 650 can be completely or partially separated from the gap between the optical transmitter 641 and the optical receiver 642, so that the degree of the shielding of the sensing signal is reduced. At this time, the sensed intensity obtained by the signal sensor, i.e. the light receiver 642, rises to the second intensity, and a triggering event is generated.

The aforementioned trigger event, i.e. the transition of the sensing intensity from the first intensity to the second intensity, can be interpreted as an input trigger by the processing circuit at the back end to generate a corresponding input signal.

It should be noted that, as shown in FIG. 8, the foregoing embodiment is described in which the key cap 604 and the two key cap ends 6014,6024 are pressed to the lowest point to generate the triggering event, i.e., the second intensity is set to the maximum sensing intensity obtained in the first embodiment. In fact, in view of the sensitivity requirements of the key assembly, a typical pressing input device (e.g., a keyboard) is not configured such that the key cap 604 is pressed to the lowest point to generate the triggering event. The push input device is typically configured such that a key cap 604 is pushed down a suitable stroke (e.g., half of the maximum stroke) to generate a trigger event. Thus, in the first embodiment, the second intensity may be a specified upper intensity threshold and the magnitude of the value is set between the first intensity and the maximum sensed intensity. When the sensing intensity gradually rises from the first intensity to the second intensity, a trigger event is generated. If the key cap 604 continues to be pressed and moves downward, the sensing strength will continue to increase, so that the trigger event remains present and is not determined to be a new trigger event. When the key cap 604 is released and moves upward such that the sensed intensity drops below the second intensity, the processing device determines that the triggering event is terminated.

As shown in fig. 9 and 10, this is a modification of the first embodiment. In this embodiment, the supporting mechanism and the backlight light source 643 are disposed on the top surface 648a of the substrate 648, and the signal generator (the light emitter 641) and the signal sensor (the light receiver 642) are disposed on the bottom surface 648b of the substrate 648; that is, the optical switch and the backlight light source 643 are provided on different surfaces of the substrate 648, and are provided on different surfaces. The substrate 648 has a notch 645, and the signal generator and the signal sensor are respectively disposed at both sides of the notch 645. As shown in fig. 9, the length and width of the slot 645 match the shape and size of the flap 650, and the front end of the flap 650 is folded downward toward the slot 645. When the key cap 604 is not depressed, the flap 650 is allowed to move through the slot 645 into the gap between the signal generator and the signal sensor. As shown in fig. 10, when the key cap 604 is pressed to make the supporting mechanism drive the blocking piece 650 to rise, the blocking piece 650 is separated from the gap between the slot 645 and the signal generator and the signal sensor, so as to change the sensing intensity. In the above-described modification, the optical switch and the backlight light source 643 are provided in a different plane, so that interference of the backlight light source 643 with the signal sensor (the light receiver 642) can be reduced, and when the optical switch is replaced with a magnetic switch, the different plane is provided similarly so that interference of the magnetic field with the signal sensor, which is changed when the backlight light source 643 is operated, can be reduced.

As shown in fig. 11, this is another modification of the first embodiment. When the signal generator and the signal sensor are a combination of the magnet 641a and the hall sensor 642a to form a magnetic switch, the magnet 641a and the hall sensor 642a may be disposed on different surfaces, for example, the magnet 641a and the backlight light source 643 are disposed on the top surface 648a, and the hall sensor 642a is disposed on the bottom surface 648 b. Although the magnet 641a and the hall sensor 642a are separated by the substrate 648, the presence of the notch 645 still forms a stable magnetic field between the magnet 641a and the hall sensor 642 a. Similarly, when the key cap 604 is not pressed, the blocking piece 650 can move through the slot 645 and enter the gap between the magnet 641a and the hall sensor 642a, so that the sensing strength of the hall sensor 642a is reduced to the minimum. When the key cap 604 is pressed to make the supporting mechanism drive the blocking piece 650 to rise, the blocking piece 650 is separated from the gap between the slot 645 and the signal generator and the signal sensor, and the sensing intensity is changed. In this variation, the magnet 641a and the hall sensor 642a can be replaced with each other.

Generally, the user does not necessarily press the center of the key cap 604 when pressing the key cap 604, for example, the edge portion of the key cap 604 is pressed to tilt the key cap 604, and the pressing force is transmitted to the key cap end 6024 of the second support 602 in a concentrated manner. At this time, the key cap end 6024 of the second support 602 receives a significantly large pressing force, while the key cap end 6014 of the first support 601 receives a relatively low pressing force. In this case, the first support 601 and the second support 602 cannot be linked, and the downward movement strokes of the two keycap ends 6014,6024 are not consistent. In the foregoing case, the generation of the trigger event will be affected; that is, after the user makes a sufficient pressing stroke, the key cap end 6014 of the first frame 601 does not make the same downward moving stroke, and the sensing intensity cannot reach the second intensity to generate the triggering event.

Referring to fig. 5, 12 and 11, in order to solve the above problem, an interlocking mechanism is disposed between the first bracket 601 and the second bracket 602 according to one or more embodiments of the present invention.

As shown in the drawing, a lower pressing piece 711 and a catching piece 712 are provided at the front end of each side arm 611,612,621,622. The lower pressing piece 711 and the catching piece 712 extend outward along the longitudinal direction of each side arm 611,612,621,622, and are arranged in parallel.

As shown in fig. 5, 12 and 11, when the bottom wall 6012 of the first frame 601 and the bottom wall 6022 of the second frame 602 are movably connected to the base plate 648, the front ends of the

side arms

611 and 612 of the first frame 601 respectively correspond to the front ends of the

side arms

621 and 622 of the second frame 602. At this time, the pressing piece 711 of the first bracket 601 is positioned above the catching piece 712 of the second bracket 602 relative to the substrate 648; conversely, the pressing piece 711 of the second bracket 602 is located above the catching piece 712 of the first bracket 601.

As shown in fig. 5, the lower pressing pieces 711 and the catching pieces 712 may be disposed at the same time on both side arm portions 611,612,621,622 of the first bracket 601 and the second bracket 602, and both the lower pressing pieces 711 and the catching pieces 712 may be disposed at the same relative positions, for example, the lower pressing pieces 711 are located on the left side and the catching pieces 712 are located on the right side in the drawing. When the first bracket 601 and the second bracket 602 are of the same type, the first bracket 601 can be used as the second bracket 602 by rotating 180 degrees in the plane. Therefore, it is not necessary to separately manufacture the first and

second supports

601 and 602 of different types.

As shown in fig. 12, 11 and 13, the extension 711a is formed by extending the lower pressing piece 711 in the lateral direction, and the end of the extension 711a is bent downward (toward the base plate) and extends forward to form the catching piece 712. Catch 712 is a longitudinal piece perpendicular to base 648, and hold-down 711 is perpendicular to catch 712. Generally, the front end of the upper side edge of the catching piece 712 is in a form of upwardly extending protrusion and has a rounded corner at the boundary of the edges. The lower compression plate 711 may be horizontally extended without being bent.

The front end of the upper side edge of the catching piece 712 of the first holder 601 is positioned below the lower pressing piece 711 of the second holder 602 with respect to the base plate 648; conversely, the front end of the upper side edge of the catching piece 712 of the second bracket 602 is positioned below the lower pressing piece 711 of the first bracket 601. As in the previous embodiment, the two side arm portions 611,612,621,622 of the first bracket 601 and the second bracket 602 may be configured with the lower pressing pieces 711 and the catching pieces 712 at the same time, and the two sets of the lower pressing pieces 711 and the catching pieces 712 are configured at the same relative positions. Generally, the length of the lower pressing piece 711 is configured such that when the first bracket 601 and the second bracket 602 are coplanar, the front end of the lower pressing piece 711 does not contact the extension 711 a.

Referring to fig. 8, when a pressing force is applied to the upper surface of the key cap 604, if an external force is concentrated on the second frame 602, the capturing piece 712 of the second frame 602 moving upward can push up the lower pressing piece 711 of the first frame 601, so as to drive the first frame 601 to move. At the same time, the catching piece 712 of the first bracket 601 also pushes up the lower pressing piece 711 of the second bracket 602, so as to drive the second bracket 602 to move. Therefore, the force focused on the second support 602 can be distributed to the first support 601 and the second support 602, so that the two key cap ends 6014,6024 can move downward with substantially the same stroke at the same time, and the key cap 604 is kept not tilted. The first bracket 601 and the second bracket 602 in the above description can be replaced with each other, that is, when the external force is concentrated on the first bracket 601, the same linking mechanism can also be used to drive the second bracket 602 to link. In this way, the key cap 604 and the two key cap ends 6014,6024 can be ensured to have substantially the same moving stroke without interfering with the generation of the triggering event.

As shown in fig. 12, when the pressing force applied to the upper surface of the key cap 604 is released, and the two key cap ends 6014,6024 are pulled by the elastic member 605 to approach each other and move upward, the aforementioned interlocking relationship is changed to that the lower pressing piece 711 presses the corresponding catching piece 712 downward, and the pulling force of the elastic member 605 is balanced between the first support 601 and the second support 602.

Therefore, no matter the key cap 604 moves upwards or downwards, the first support 601 and the second support 602 can be pulled by each other, so as to balance the stress on the first support 601 and the second support 602, and reduce the occurrence of the triggering event caused by the deflection of the key cap 604 in the pressing or releasing process.

Referring to fig. 14 and 15, a key assembly according to a second embodiment of the present invention is disclosed for illustrating a variation of the shielding mechanism 670.

As shown in fig. 14 and 15, in the second embodiment, the shielding mechanism 670 includes a pivot portion 671, a connecting piece 672 and a blocking piece 650. The pivot 671 is rotatably disposed on the top surface 648a of the substrate 648. Substantially, the rotation axis of the pivot portion 671, the rotation axis of the first bracket 601 and the rotation axis of the second bracket 602 are parallel to each other.

As shown in fig. 14 and 15, the connecting piece 672 extends from the pivot portion 671, and in the second embodiment, the connecting piece 672 is a longitudinal sheet arranged perpendicular to the top surface 648 a. The end of the connecting piece 672 has an open slot 672a, and the opening of the open slot 672a is located at the end of the connecting piece 672. The opening slot 672a extends toward the pivot portion 671, and preferably, the edge of the opening is provided with a rounded corner. Accordingly, one of the two key cap ends 6014,6024 is provided with a guide tab 6145 (the key cap end 6014 of the first holder 601 will be described as an example below).

As shown in fig. 14 and 15, the guide tab 6145 is a tab arranged perpendicular to the connecting tab 672 for insertion into the open slot 672 a. The width of the open slot 672a is greater than the thickness of the guide tab 6145. Therefore, the guiding sheet 6145 can slide in the opening slot 672a and can also swing along the width direction of the opening slot 672a, so that the connecting sheet 672 can be movably connected to the key cap end 6014 of the first bracket 601. In this embodiment, the insertion hole 613a disposed in the support body 613 can be omitted. Specifically, the guide piece 6145 is provided to the

holder bodies

613 and 623 which are the key cap ends 6014 and 6024.

As shown in fig. 16 and 17, fig. 16 and 17 are simplified, and only the substrate 648, the light emitter 641, the light receiver 642, the first bracket 601 and the shielding mechanism 670 are remained. In the second embodiment, the connecting piece 672 and the flap 650 extend toward the same side with respect to the rotation axis of the pivot 671, and the end of the flap 650 is located substantially between the end of the connecting piece 672 and the pivot 671. One of the light emitter 641 and the light receiver 642 may be located between two pivoting tabs 673, that is, two pivoting tabs 673 are located at two sides of the signal transmission direction, and the pivoting portion 671 is located above one of the light emitter 641 and the light receiver 642, and the other is located between the end of the blocking piece 650 and the projection of the end of the connecting piece 672 on the top surface 648 a. Likewise, in the second embodiment, the positions of the light emitter 641 and the light receiver 642 as the signal generator and the signal sensor may be exchanged.

Referring to fig. 16 and 17, the shielding mechanism 670 rotates according to the rotation axis of the pivot 671 in the direction perpendicular to the top surface 648a of the base plate 648, and the linear moving direction of the catch 650 and the connecting piece 672 is the same. In addition, the front ends of the stoppers 650 may be bent toward the base plate 648 to shorten the distance between the front ends of the stoppers 650 and the top surface 648 a.

Fig. 16 shows the key cap 604 (the key cap 604 is not shown) not pressed, and the pulling force provided by the elastic member 605 makes the two key cap ends 6014,6024 approach each other and move upward, so as to move the key cap 604 upward to the highest point that can be reached in this embodiment. At this time, the portion of the connecting sheet 672 connected to the key cap end 6014 moves upward to drive the front end of the blocking sheet 650 to move upward to the highest point, and the front end of the blocking sheet 650 is separated from the gap between the optical transmitter 641 and the optical receiver 642, so that the transmission of the sensing signal is not blocked by the blocking sheet 650, or the blocking of the sensing signal by the blocking sheet 650 is reduced to the minimum extent. At this time, the sensing intensity obtained by the light receiver 642 is the first intensity. The first intensity will typically be the maximum sensed intensity in the second embodiment; however, the value of the first intensity is not necessarily equal to the maximum receiving intensity that can be obtained by the signal sensor, because when the key cap 604 is at the high point and the flap 650 is at the highest point, the transmission of the sensing signal may be partially interrupted by the flap 650.

Fig. 17 shows a state where the key cap 604 (the key cap 604 is not shown) is pressed to the lowest point, and the key cap 604 is pressed and moved downward to transmit the pressing force to the two key cap ends 6014,6024, and the two key cap ends 6014,6024 are carried and moved downward to the lowest point. At this time, the portion of the connecting piece 672 connected to the keycap ends 6014,6024 moves downward, and the front end of the blocking piece 650 is driven to move downward to be inserted into the gap between the light emitter 641 and the light receiver 642 and reach the lowest point which can be reached in this embodiment, so that the degree of the sensing signal being blocked is increased. At this time, the sensed intensity obtained by the light receiver 642 is decreased to the second intensity, and a trigger event is generated; the trigger event causes the processing circuit to interpret the input trigger to generate a corresponding input signal.

It should be noted that, as shown in fig. 17, the foregoing embodiment is described in which the key cap 604 is pressed to the lowest point to generate the triggering event, i.e., the second intensity is set to the minimum sensing intensity obtained in the second embodiment. In practice, the second strength may be a threshold value of a specified lower limit of the received strength, and the magnitude of the value is set between the first strength and the minimum sensed strength. When the sensing intensity gradually decreases from the first intensity to be equal to or less than the second intensity, a trigger event is generated. If the key cap 604 continues to be pressed downward, the sensing strength may continue to decrease such that the trigger event remains present and is not determined to be a new trigger event. When the key cap 604 is released such that the sensed intensity rises above a second intensity, the processing device determines that the triggering event is terminated.

Fig. 18 and fig. 19 show a key assembly according to a third embodiment of the present invention, which is used to illustrate a variation of the linking mechanism.

As shown in fig. 18 and 19, the pressing piece 711 and the catching piece 712 of the second embodiment are both bent downward (toward the substrate 648) slightly. Further, a catching part 712a bent upward (bent in a direction away from the substrate 648) is disposed at the tip of the catching piece 712, and a bent angle is formed between the catching part 712a and the catching piece 712. Referring to fig. 19, the catching piece 712 is bent at a larger angle than the lower pressing piece 711, and the lower pressing piece 711 has a length larger than the catching piece 712. As in the first embodiment, the two side arm portions 611,612 of the first bracket 601 and the two side arm portions 621,622 of the second bracket 602 may be simultaneously provided with the lower pressing pieces 711 and the catching pieces 712, and both sets of the lower pressing pieces 711 and the catching pieces 712 may be provided at the same relative positions.

When the key assembly is pressed, the capturing piece 712 of each bracket 601,602 moving upward can jack up the lower pressing piece 711 of the other bracket 601, thereby driving the two brackets 601,602 to move together. When the external force pressing on the key cap 604 is released and the two key cap ends 6014,6024 bear the pulling force of the elastic member 605 and approach each other, the aforementioned linkage relationship is converted into that the lower pressing piece 711 presses the corresponding capturing piece 712 downwards, and the pulling force of the elastic member 605 is balanced between the first support 601 and the second support 602. When the lower pressing piece 711 enters the corresponding bending angle, the catching part 712a stops the lower pressing piece 711 from moving further, and the two keycap ends 6014,6024 reach the highest point in the system.

Referring to fig. 20 and 21, a linkage mechanism according to a fourth embodiment of the present invention is disclosed, and is applied to one or more embodiments of the present invention.

As shown in fig. 20 and 21, the lower pressing piece 711 is a longitudinal piece perpendicular to the base plate 648, and the catching piece 712 is perpendicular to the lower pressing piece 711. Generally, the front end of the lower edge of the lower pressing plate 711 is in the form of a protrusion extending downward (toward the substrate 648), and has a rounded corner at the boundary of the edges. The catching piece 712 is bent and then bent forward, thereby forming a catching portion 712a bent forward. The front end of the lower edge of the lower pressing piece 711 is used to contact the catching portion 712 a.

The front end of the lower edge of the lower pressing piece 711 of each bracket is located above the forward bent portion of the catching piece 712 of the other bracket with respect to the base plate 648. As in the first embodiment, the two side arm portions 611,612 of the first bracket 601 and the two side arm portions 621,622 of the second bracket 602 may be simultaneously provided with the lower pressing pieces 711 and the catching pieces 712, and both the sets of the lower pressing pieces 711 and the catching pieces 712 may be arranged at the same relative positions. Generally, the length of the lower pressing piece 711 is configured such that when the first bracket 601 and the second bracket 602 are coplanar, the front end of the lower pressing piece 711 does not contact the portion of the catching piece 712 bent downward.

When the key assembly is pressed, the catching piece 712 of one bracket moving upwards can jack up the lower pressing piece 711 of the other bracket, so as to drive the two

brackets

601 and 602 to be linked. When the external force pressing the key cap 604 is released, the linkage relationship is converted into the lower pressing piece 711 pressing the corresponding capturing piece 712 downwards, so that the first bracket 601 and the second bracket 602 are driven by each other to balance the pulling force of the elastic member 605.

The present invention is capable of other embodiments, and various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention.

Claims

1. A key assembly, the key assembly comprising:

a shielding mechanism comprising:

the pivoting part is rotatably arranged on the top surface;

2. The key assembly of claim 1, wherein the support mechanism comprises:

the elastic piece is connected with the two keycap ends;

3. The key assembly of claim 2 wherein one of the two key ends is provided with a receptacle and the connecting tab is slidably inserted into the receptacle.

4. The key assembly of claim 2, wherein the connecting plate is a longitudinal plate disposed perpendicular to the top surface and has an open slot at an end thereof, one of the two keycap ends is provided with a guide plate for insertion into the open slot, and the width of the open slot is greater than the thickness of the guide plate.

5. The key assembly of claim 1, further comprising a key cap disposed on the top of the support mechanism to be supported above the top surface by the support mechanism, and the support mechanism supports the key cap to move up and down relative to the substrate.

6. The key assembly of claim 5, further comprising a backlight source disposed on the top surface for projecting illumination toward the keycap.

7. The key assembly of claim 6, further comprising a diffuser coupled to the top surface and covering the backlight source.

8. The key assembly of claim 6, wherein the substrate has a slot, one of the signal generator and the signal sensor and the backlight source are located on different sides of the substrate, and a front end of the blocking sheet is adapted to be inserted into or removed from a gap between the signal generator and the signal sensor through the slot.

9. The key assembly of claim 1, wherein the signal generator and the signal sensor are a combination of an optical receiver and an optical transmitter, or the signal generator and the signal sensor are a combination of a magnet and a hall sensor.

10. The key assembly of claim 1, wherein the signal generator and the signal sensor are arranged along a signal transmission direction perpendicular to a rotation axis of the pivot portion.

11. The key assembly of claim 1, wherein the blocking piece and the connecting piece are located on two sides or on the same side of the pivoting portion in the axial direction of rotation.

12. The key assembly of claim 11, wherein the shielding mechanism further comprises two pivoting tabs respectively extending from two opposite sides of the pivoting portion, the two pivoting tabs being disposed along a rotational axis of the pivoting portion.

13. The key assembly of claim 1, further comprising a shielding element disposed on the top surface, the shielding element having a window; the shielding element surrounds the signal generator and the signal sensor, and the blocking piece penetrates through the window.

14. A supporting mechanism for a key, the supporting mechanism comprising:

a substrate having a top surface; and

two supports, each support is respectively provided with a bottom plate end and a keycap end, each bottom plate end is movably connected with the substrate, and the two supports are unfolded outwards to enable the two keycap ends to be away from each other; each bracket is also provided with a body and a side arm part, the side arm part extends to the corresponding body, each body respectively forms each keycap end, and the tail end of each side arm part respectively forms each bottom plate end correspondingly;

15. The supporting mechanism as claimed in claim 14, wherein the lower pressing plate and the capturing plate are bent toward the substrate, the capturing part bent away from the substrate is disposed at a front end of the capturing plate, and a bending angle is formed between the capturing part and the capturing plate.

16. The supporting mechanism for a keypad according to claim 15, wherein the angle of bending the capturing plate is larger than the angle of bending the pressing plate, and the length of the pressing plate is larger than the length of the capturing plate.

17. The support mechanism as claimed in claim 14, wherein the pressing piece is perpendicular to the substrate, and the catching piece is perpendicular to the pressing piece.

18. The supporting mechanism for push-button switch as claimed in claim 17, wherein the front end of the lower edge of the lower pressing plate is in a form of extending and protruding toward the base plate; the catching piece is bent and then bent towards the front to form a catching part bent towards the front, and the lower edge of the lower pressing piece is used for contacting the catching part.

19. The supporting mechanism as claimed in claim 14, wherein the pressing piece extends outward along the longitudinal direction of the side arm, and the lateral extension of the pressing piece forms an extension, and the end of the extension has the catching piece bent toward the base plate and extending forward.