Key module for a keyboard and keyboard

A key module (110) for a keyboard is presented. The key module (110) comprises a key tappet (220). The key tappet (220) comprises a coupling portion (322) for coupling with a keycap for the key module (110). The key tappet (220) comprises at least one guiding portion (326, 328) for guiding a translational actuation movement of the key tappet (220) between a rest position and an actuated position. The key tappet (220) comprises at least one tappet stop (324) for limiting the actuation movement. The key module (110) also comprises a trigger element (350) for triggering a switch signal of the key module (110) in response to the actuation movement. The trigger element (350) is attachable to the key tappet (220). The key module (110) further comprises a module housing (230), wherein the module housing (230) is integrally formed. The module housing (230) comprises at least one positioning protrusion (334) for positioning the key module (110) and a circuit substrate of the keyboard. The module housing (230) is formed to movably accommodate the key tappet (220), in order to enable the actuation movement of the key tappet (220) relative to the module housing (230). The module housing (230) comprises at least one housing stop (332) for abutment against the at least one tappet stop (324) of the key tappet (220) in the rest position of the key tappet (220). Moreover, the key module (110) comprises elastic means (340). The elastic means (340) is configured to bias the key tappet (220) into the rest position in an assembled state of the key module (110).

The present invention relates to a key module for a keyboard and to a keyboard having at least one such key module.

Different types of key switches may be employed in keyboards typically used in connection with computers. In particular, mechanical key modules can be used as a key switches. There are different types of mechanical key modules.

A key module having a lid element, a tappet, a contact element unit, a contact piece and a housing element is described in post-published DE 10 2017 106 406 A1.

Against this background, the present invention provides an improved key module for a keyboard and an improved keyboard according to the main claims. Advantageous embodiments can be seen from the dependent claims and the subsequent description.

According to embodiments of the approach described here, in particular, a mechanical key switch or mechanical key module with a one-piece, integral module housing for receiving a key tappet can be provided. Furthermore, for example, the key module may comprise only one trigger element configured to cause or trigger a switch signal of the key module via an electric circuit on a circuit substrate of the keyboard. Moreover, for example, the key module may be configured to guide the key tappet on a majority of its outer faces in the module housing.

Advantageously, a long-life and robust mechanical key module which can also be realized in a cost-saving manner can be provided. Among other things, this can be achieved by keeping a number of parts of the key module low. Furthermore, tappet guidance can be improved, in particular canting in the course of an actuation movement can be avoided. Also, the key module can be replaced in a simple and uncomplicated manner with respect to the keyboard, particularly also by an end user.

What is presented is a key module for a keyboard, wherein the key module comprises:

a key tappet, wherein the key tappet comprises a coupling portion for coupling to a keycap for the key module, wherein the key tappet comprises at least one guiding portion for guiding a translational movement of the key tappet between a rest position and an actuated position, wherein the key tappet comprises at least one tappet stop for limiting the actuation movement;

a trigger element for triggering a switch signal of the key module in response to the actuation movement, wherein the trigger element is attachable to the key tappet;

a module housing, wherein the module housing is integrally formed, wherein the module housing comprises at least one positioning for positioning the key module on the circuit substrate of the keyboard, wherein the module housing is formed to movably accommodate the key tappet, in order to enable the actuation movement of the key tappet relative to the module housing, wherein the module housing comprises at least one housing stop for abutting against the at least one tappet stop of the key tappet in the rest position of the key tappet; and

elastic means, the elastic means being configured to bias the key tappet in the rest position in an assembled state of the key module.

The keyboard may be provided for a computer or the like, for example. The keyboard may comprise at least one key module. The key module may be part of a key or may represent a key. Thus, one key module per key can be provided. The key module may also be referred to as a mechanical push-button or mechanical push-button switch. The key tappet may be integrally formed. The tappet stop and the housing stop may be formed to enable a latch connection or snap connection between the key tappet and the module housing, in order to hold the key tappet in the module housing. In the rest position, the key tappet may be accommodated partially within the module housing. In the actuated position, the key tappet may be accommodated completely within the module housing or completely except for the end portion of the coupling portions. The elastic means may be a compression spring. The elastic means may function as a return spring for the key module. The elastic means may cause a linear force-displacement characteristic in the course of the actuation movement. In other words, the elastic means may comprise a linear spring characteristic. Alternatively, the elastic means may comprise a progressive spring characteristic. The circuit substrate may be a circuit board. The positioning protrusion may be formed as a stud, pin or the like.

According to an embodiment, the module housing may comprise at least one mounting portion for mounting the key module the keyboard with positive locking and additionally or alternatively with non-positive locking. The mounting portion may be and as a flange and additionally or alternatively a snap-fit or the like. The key module may be connected to the circuit substrate while avoiding an adhesive bond between the key module and the circuit substrate of the keyboard. Such an embodiment offers the advantage that a solder-free connection between the key module and the circuit substrate can be realized in a cost-saving manner. Cost may also be saved because a wider selection of materials also with less temperature resistant materials can be used for the key module depending on the ambient temperature of the operational environment. Moreover, a solder-free connection offers simple replacement of key modules by an expert or directly by the end user. This opens up an additional possibility of individual keyboard design, which may be advantageous particularly with gaming users.

Furthermore, the at least one guiding portion of the key tappet may comprise a surface portion of the key tappet. Additionally or alternatively, the at least one guiding portion of the key tappet may comprise a guiding stud formed to plunge into a bulge of the module housing in the course of the actuation movement, wherein the bulge comprises the positioning protrusion. Such an embodiment offers the advantage that a sliding actuation movement of the key tappet relative to the module housing can be enabled with reliable guidance of the key tappet the module housing.

The key tappet may also comprise a surface portion formed as a multi-sided pipe. In a region enclosed by the surface portion, an intermediate bottom may be formed.

From the intermediate bottom, the coupling portion may extend in a first direction partially out of the surface portion. A guiding stud as guiding portion may extend from the surface portion in a second direction opposite to the first direction partially out of the surface portion. Thus, the coupling portion and the guiding stud may be arranged on opposite sides of the intermediate bottom. The surface portion may be a four-sided pipe with chamfered edges. The tappet stop may be formed on the surface portion. A proportion of a dimension of the surface portion with respect to a dimension of the key module along an axis of the actuation movement may be more than 75 percent, more than 80 percent, more than 85 percent or more than 90 percent, for example. Such an embodiment offers the advantage that reliable and stable guidance of the key tappet in the module housing with a lock against rotation and anti-canting protection can be achieved.

Moreover, the key tappet may be formed of translucent material or opaque material. The module housing may be formed of translucent material or opaque material. Such an embodiment offers the advantage that uniform illumination of a keycap coupleable to the key tappet can be achieved from the circuit substrate. Also, illumination of the entire module housing, and thus an environment of the keycap, can be enabled if required.

According to an embodiment, the trigger element may be a contactor for electrically shorting contact pads of the circuit substrate of the keyboard. The trigger element may comprise at least one contact finger for contacting the contact pads while causing friction, which contact finger is elastically deformable in the course of the actuation movement, and an attachment portion for attaching the trigger element to the key tappet. The contactor may be integrally formed. At least the at least one contact finger may be formed from electrically conductive material. In particular, the contactor may be integrally formed as a stamped and bent part from a metal material. The at least one contact finger may exhibit a linear or progressive spring characteristic upon deformation. In the rest position, the at least one contact finger may be spaced from the circuit substrate. In the actuated position, the at least one contact finger may contact the contact pads of the circuit substrate. In particular, the contactor may comprise two contact fingers, wherein the two contact fingers may again be slotted, so that for contact fingers are provided altogether. Such an embodiment offers the advantage that safety of contact can be increased, and thus a switch signal of the key module can be provided in a reliable and reproducible manner. An overall non-linear force-displacement characteristic may also be achieved by way of a combination of a spring force of the elastic element and a spring force of the at least one contact finger in the course of the actuation movement of the key module.

The trigger element may comprise a deflection portion for causing acoustic feedback and additionally or alternatively tactile feedback, wherein the deflection portion is elastically deflectable in the course of the actuation movement. The module housing may comprise an actuation cam formed to deflect the deflection portion of the trigger element in the course of the actuation movement. Such an embodiment offers the advantage that both the triggering of the switch signal and palpable and additionally or alternatively audible feedback of the actuation of the key module can be realized by means of a single component, the contactor.

Furthermore, the deflection portion may be arranged between the contact finger and the attachment portion of the trigger element. The deflection portion may be formed to be U-shaped with a first leg and a second leg. The first leg may be rigidly connected to the trigger element. The second leg may be formed as a clapper movable relative to the first leg and having a control cam for interaction with the actuation cam of the module housing. Moving along a contour of the control cam may effect a non-linear force-displacement characteristic of a deflection of the second leg relative to the first leg in the course of the actuation movement. In the rest position, the control cam of the clapper is spaced from the actuation cam of the housing. Such an embodiment offers the advantage that the control cam and a strike surface, against which the clapper strikes for acoustic feedback on the contactor, are arranged on a single component and particularly on a single subsection of the contactor. Thus, reliability and reproducibility of feedback can be increased.

The trigger element may also comprise an opening. The second leg may engage with the opening. The opening may be formed to enable a first movement of the second leg toward the first leg and away from the first leg for the tactile feedback and optionally additionally a second movement of the second leg transversal with respect to the first movement for the acoustic feedback. In particular, the second movement may take place with a component of movement normal with respect to the first movement. The opening may be formed as a through-hole or a fork or the like. In particular, the opening may be formed as an elongated hole. The opening is configured to effect limitation of a movement of the second leg. The first movement and the second movement may be caused by interaction of the control cam and the actuation cam. Such an embodiment offers the advantage that the desired type of feedback or the desired types of feedback can be provided in a reliable, defined and reproducible manner.

According to an embodiment, the module housing may comprise an abutment surface. The trigger element may be arranged so as to abut on the abutment surface in the rest position of the key tappet. The abutment surface may be formed at least so that the trigger element and thus the key tappet can be prevented from sliding back to a position prior to first-time actuation. Such an embodiment offers the advantage that settling vibrations of the trigger element after returning from the actuation position to the rest position can be dampened.

What is also presented is a keyboard, wherein the keyboard comprises:

at least one exemplar of an embodiment of the previously presented key module; and

a circuit substrate, wherein the at least one key module is arranged on the circuit substrate.

Thus, at least one previously presented key module may be employed or used in conjunction with the keyboard. The at least one key module may be attached directly to the circuit substrate.

According to an embodiment, the circuit substrate may comprise at least one hole into which the at least one positioning protrusion of the module housing of the at least one key module is inserted. In particular, positive locking between the key module and the circuit substrate may be achieved here. Such an embodiment offers the advantage that simple and accurate positioning of the key module relative to the circuit substrate can be achieved.

In particular, the at least one key module and the circuit substrate may be connected to each other exclusively by positive locking and additionally or alternatively by non-positive locking. The positive locking and additionally or alternatively non-positive locking between key module and circuit substrate may be affected by means of the at least one positioning protrusion and at least one mounting portion of the module housing. Such an embodiment offers the advantage that a reliable, inexpensive connection simply detachable for replacement can be realized.

At least one light-emitting diode for illuminating the at least one key module and additionally or alternatively further electronic devices may also be arranged on or in the circuit substrate. Contact pads, which may be electrically connected to each other upon actuation of the at least one key module, may also be arranged on or in the circuit substrate. The at least one light-emitting diode and additionally or alternatively the further electronic devices may be attached by means of a surface-mounting process or a soldering process. The further electronic devices may be resistors, diodes or the like. Such an embodiment offers the advantage that the key module can be kept free from electronics. Furthermore, simple illumination of the key module or the key can be achieved.

Furthermore, the keyboard may comprise a fixing element for fixing the at least one key module to the circuit substrate. The fixing element may be formed as a key frame between the circuit substrate and a keyboard top or as a keyboard top. The fixing element may be configured to engage in positive and additionally or alternatively non-positive locking with at least one mounting portion of the module housing of the key module. Such an embodiment offers the advantage that a keyboard can be realized inexpensively, wherein long-life and robust key modules can be replaced easily and allow for precise actuation.

In the subsequent description of preferred embodiments of the present invention, the same or similar reference numerals shall be used for similarly acting elements illustrated in the various figures, wherein repeated description of these elements shall be omitted.

FIG. 1shows a schematic illustration of a keyboard100with key modules110according to an embodiment. For example, the keyboard100is part of a notebook computer, laptop computer or the like. Alternatively, the keyboard100is designed as a peripheral device for a computer, in particular.

The keyboard100comprises a circuit substrate102. The circuit substrate102is a circuit board, conductor board or the like, for example. According to the embodiment illustrated inFIG. 1, the keyboard100comprises a plurality of key modules110. The key modules110are arranged on the circuit substrate102.

According to the embodiment illustrated inFIG. 1, the keyboard100also comprises a fixing element104for fixing the key modules110to the circuit substrate102. More specifically, the fixing element104is formed to establish positive locking and additionally or alternatively non-positive locking with the key module. Herein, the fixing element104is only exemplarily formed as a key frame. Alternatively, the fixing element104may be formed as a keyboard top.

Furthermore, according to the embodiment shown and described inFIG. 1, a keycap106is attached to each key module110. Each keycap106is coupled to a key module110of its own. Each unit of key module110keycap106represents a key of the keyboard100. Alternatively, each key module110represents a key of the keyboard100. Particularly the key modules110shall be explained in greater detail with reference to subsequent figures.

The keycap106represents a part of a key visible and touchable for a user of the keyboard100. Actuation of a key module110is effected by pressing onto the keycap106. Each key module110is configured to react with a force-displacement characteristic of resistance or reset force to an actuation force. Furthermore, each key module110is configured to establish an electrical connection in response to actuation with a pre-definable actuation path, thereby executing a switching procedure.

FIG. 2shows a partially exploded view of a subsection of a keyboard100according to an embodiment of the present invention. The keyboard100here corresponds to or is similar to the keyboard fromFIG. 1. The circuit substrate102, the fixing element104formed as the keyframe, and the key module110are shown here.

A hole201is formed in the circuit substrate102. A positioning protrusion of the key module110can be introduced or inserted into the hole201of the circuit substrate102. Furthermore, two electric contact pads203or switch pads, which can be shorted by the key module110in an actuation movement of the key module110, are arranged on or in the circuit substrate102. Moreover, according to the embodiment illustrated here, a plurality of electronic devices205are arranged on or in the circuit substrate102. The electronic devices205are a light-emitting diode and, for example, electric resistors and/or the like. The contact pads203and the devices205are arranged in the neighborhood of the hole201.

A holding opening207for being the key module110is formed the fixing element104. The key module110can be inserted and latched in the holding opening207. When the circuit substrate102and the fixing element104are stacked on each other, the hole201, the contact pads203and the devices205of the circuit substrate102are exposed by the holding opening207of the fixing element104.

A key tappet220and a module housing230are shown of the key module110in the illustration ofFIG. 2. In an actuation movement, the key tappet220is movable relative to the module housing230. The key tappet220is shown to be accommodated in the module housing230in the illustration ofFIG. 2. Specifically, the key tappet220is shown in a rest position relative to the module housing230here, wherein the key tappet220is partially accommodated in the module housing230in the rest position. The key module110shall be explained in greater detail with reference to subsequent figures.

In other words,FIG. 2shows an exploded view of a subsection of a keyboard100. E.g. at least one light-emitting diode for switch illumination, resistors, diodes or sensors, for example, may be mounted on the circuit substrate102as the devices205by means of a surface-mounting process or conventional soldering process. The key module110is positioned on the circuit substrate102by means of the whole201and a positioning protrusion formed as a stud of the key module110. Fixing of the key module110takes place by means of a snap-action connection in the holding opening207of the fixing element104. According to another embodiment, a top part of the keyboard100may function as the fixing frame or fixing element104. Simple assembly and disassembly for replacing the key module110are possible.

FIG. 3shows an exploded view of the key module110fromFIG. 2. The key module110comprises the key tappet220, the module housing230, elastic means340and a trigger element350.

When the key module110is being actuated, the key tappet220is translationally movable relative to the module housing230between a rest position and an actuated position. This is referred to as the actuation movement of the key tappet220. According to the embodiment illustrated inFIG. 3, the key tappet220is integrally formed. According to an embodiment, the key tappet220is formed of a translucent material. Thus, uniform illumination of a keycap can be realized. According to another embodiment, the key tappet220is formed of an opaque material.

The key tappet220comprises a coupling portion322. The coupling portion322is formed to be mechanically coupleable to a keycap for the key module110. The coupling portion322extends along an axis of movement of the actuation movement. According to the embodiment illustrated here, the coupling portion322has a cross-shaped cross-sectional profile.

The key tappet220further comprises at least tappet stop324for limiting the actuation. Even though it is only implicitly shown inFIG. 3owing to the illustration, the key tappet220comprises two tappet stops324. Each of the tappet stops324is formed as a step, a shoulder or a ledge.

The key tappet220further comprises at least one guiding portion for guiding the actuation. According to the embodiment illustrated here, the key tappet220comprises a surface portion326of the key tappet220and a guiding stud328as guiding portions. The surface portion326is formed as a multi-sided pipe, according to an embodiment. More specifically, according to the embodiment illustrated here, the surface portion326is formed as a four-sided pipe with chamfered edges as a lock against rotation. In other words, the surface portion326is formed by outside walls of the key tappet220extending along the axis of the actuation movement. The guiding stud328also extends along the axis of the actuation movement.

The trigger element350of the key module110is configured to trigger a switch signal of the key module110in response to the actuation movement. More specifically, the trigger350is formed to trigger the switch signal by acting on the circuit substrate of the keyboard. The trigger element350is attachable to the key tappet220. In particular, the trigger element350is attachable to an area of the key tappet220closed by the surface portion326. According to the embodiment illustrated here, the trigger element350is a contactor350. The contactor350shall be explained in greater detail with reference to subsequent figures.

The module housing230is integrally formed. The module housing230is formed to movably accommodate the key tappet220, in order to enable the actuation movement of the key tappet220relative to the module housing230. A body of the module housing230here is trough-shaped. According to an embodiment, the module housing230is formed of translucent material. Thus, ambient illumination for the keycap can be realized. According to another embodiment, the module housing230is formed of a brake material. In this way, illumination of the key module110can be restricted to the keycap.

The module housing230comprises at least one housing stop332for limitation of movement for the key tappet220. Even though it is only implicitly illustrated inFIG. 3, the module housing230comprises two housing stops332. Each of the housing stops332is formed to abut against a respective one of the tappet stops324of the key tappet220in the rest position of the key tappet220. Each of the housing stops332is formed as a step, a shoulder or a ledge, complementary to the respective one of the tappet stops324. The key tappet220can be latched and held in the module housing230by way of interaction of the tappet stops324and the housing stops332.

Furthermore, the module housing230comprises at least one positioning protrusion334. The positioning protrusion334is formed to position the module housing230and thus the assembled key module110on the circuit substrate of the keyboard. The positioning protrusion334is formed as a stud or pin. The positioning protrusion334extends along the axis of the actuation movement. According to the embodiment illustrated here, the positioning protrusion334is formed by a bulge of the module housing230. The guiding stud328of the keycap220is formed to plunge into this bulge the course of the actuation movement.

Moreover, according to the embodiment illustrated here, the module housing230comprises a mounting portion336for mounting the key module110in the keyboard with positive locking and/or non-positive locking. The mounting portion336comprises latching protrusions or lugs for latching the fixing element, in particular in the holding opening of the fixing element of the keyboard. A flange338formed around the module housing230functions as a further mounting portion or as a stop with respect to the positive and/or non-positive locking.

According to the embodiment illustrated here, the elastic means340of the key module110is a compression spring. The elastic means340is configured to bias the key tappet220in the rest position in an assembled state of the key module110. The elastic means340can be put over the guiding stud328of the key tappet220. Thus, the elastic means340is arrangeable between the key tappet220and the module housing230. The elastic means340may also be referred to as a return spring.

According to an embodiment, the key tappet220is transparent or translucent, for example, in order to uniformly illuminate symbols on the keycap. Furthermore, the module housing230is translucent, for example, in order to illuminate gaps between keys, or is opaque in order to leave gaps unilluminated. According to an embodiment, the actuation movement has a linear-progressive force-displacement characteristic. The elastic means340has a linear force-displacement characteristic. From a switching point of the key module110onward, the contactor350is increasingly biased and changes the force-displacement characteristic of the key module110.

FIG. 4shows the contactor350fromFIG. 3. The contactor350is integrally formed. For example, the contactor350is formed of a metal material by punching and bending. The contactor350is configured to electrically short the contact pads of the circuit substrate of the keyboard.

The contactor350comprises an attachment portion452, by means of which the contactor350is attachable to the key tappet of the key module. More specifically, the attachment portion452of the contactor350can be press fit into the key tappet. The contactor350also comprises at least one contact finger454. According to the embodiment illustrated here, the contactor350comprises two contact fingers454, for example. The contact fingers454are elastically deformable in the course of the actuation movement. The contact fingers454are configured to contact the contact pads of the circuit substrate while generating friction in the course of the actuation movement toward the actuated position. According to the embodiment illustrated here, end portions of the contact fingers454are curved or bent. According to an embodiment, the contactor350comprises two double fingers454or a total of four contact fingers454. In this way, redundant contact can be achieved. Thus, reliability and safety of contact can be increased further.

According to the embodiment illustrated here, the contactor350further comprises a deflection portion458. The deflection portion458is elastically deflectable in the course of the actuation movement. The deflection portion458is configured to produce acoustic feedback and/or tactile feedback in response to its deflection. The deflection portion458is arranged between the attachment portion452and the contact fingers454. More specifically, the deflection portion458is U-shaped. The deflection portion458comprises a first leg462and a second leg464. The deflecting portion558is rigidly or fixedly connected to the contactor350on the first leg462. The second leg464is elastically movable relative to the first leg462in the course of the actuation movement. The second leg464is formed as a clapper or functions as a clapper of the contactor350. A control cam466is arranged in a free end portion of the second leg464. In the course of the actuation movement, the control cam466comes to interact with an actuation cam of the module housing, in order to effect the deflection of the deflection portion458. Furthermore, a strike portion468is arranged in the free end portion of the second leg464. The free end portion of the second leg464engages in opening456of the contactor350. Beyond the passage through the opening456, the strike portion468is bent or curved. The opening456is formed in the region of the deflection portion458. The opening456is formed to enable an elastic first movement of the second leg464toward the first leg462and away from the first leg462for the tactile feedback. According to the embodiment illustrated here, the opening456is further formed to enable an elastic second movement of the second leg464transversal with respect to the first movement for the acoustic feedback. Here, a sudden strike of the strike portion468occurs against a rim of the opening456. According to the embodiment illustrated here, the opening456is an elongated hole. According to another embodiment, the opening456may also be a fork or the like.

The deflection portion458may also be referred to as a click mechanism with a U-shaped click spring. Stiffness or elasticity of the deflection portion458for the first movement and the second movement is adjustable when forming the deflection portion458. A purely tactile feedback is realized by shortening the opening456correspondingly so that the clapper or strike portion468of the second leg464can only be deflected for the first movement. Moving along a contour of the control cam466in the course of the actuation movement causes a non-linear force-displacement characteristic and does not cause any audible sound. According to an embodiment, the contactor350can be formed without the deflection portion458. This makes the contactor350even more simple and inexpensive. In summary, the contactor350can be realized in three variants depending on the desired switching characteristic: linear-progressive tactile tactile and acoustic or clicking. A linear-progressive characteristic in the key module is brought about as follows: the elastic means has a linear force-displacement characteristic. From a switching point of the key module onward, the contact fingers454of the contactor350are increasingly biased and change the force-displacement characteristic of the key module. Upon switch actuation or for triggering the switch signal, the contact pads of the circuit substrate are shorted by means of the contact fingers454, with the respective switch state of the key being generated.

FIG. 5shows a partially sectional view of a subsection of the keyboard100according to an embodiment of the present invention. The subsection of the keyboard100corresponds to the subsection illustrated inFIG. 2, wherein the key module110is arranged on the circuit substrate102and the fixing element is omitted. Here, the circuit substrate102with the contact pads203, which only one is designated with a reference numeral for lack of space, and the key module110are shown of the keyboard100. The key tappet220with the coupling portion322, the surface portion326, the guiding stud328and an intermediate bottom529, the module housing230with the positioning protrusion334and an actuation cam539, the elastic means340and the trigger element formed as contactor350with the contact fingers454, of which only one is designated with a reference numeral for lack of space, and the control cam466are shown of the key module110in the illustration ofFIG. 5.

The key module110is shown in the rest position. Herein, a subsection of the surface portion326protrudes from the module housing230. The guiding stud328of the key tappet220plunges into a bulge of the module housing230, which comprises or forms the positioning protrusion334. Furthermore, the actuation cam539of the module housing230is shown. The actuation cam539is formed to interact with the control cam566of the contactor350, in order to deflect the deflection portion of the contactor350in the course of the actuation and or move the second leg relative to the first leg. What is also shown is the intermediate bottom529, which is formed in the region enclosed by the surface portion326of the key tappet220. The coupling portion322of the key tappet220extends from the intermediate bottom529in a first direction. The guiding stud328extends from the intermediate bottom529in a second direction opposite to the first direction.

FIG. 6shows a partially sectional view of a subsection of a keyboard100according to an embodiment of the present invention with a key module110in a rest position. The subsection of the keyboard100corresponds to the subsection illustrated inFIG. 2, wherein the key module110is arranged on the circuit substrate102and the fixing element is omitted. Thus, the illustration inFIG. 6is similar to the illustration fromFIG. 5, except that a sectional plane is changed. InFIG. 6, the circuit substrate102and the key module110are shown of the keyboard100, wherein the key tappet220with the coupling portion322, the module housing230with the positioning protrusion334, the elastic means340and a contact finger454of the contactor are shown of the key module110. In the rest position of the key module110, the at least one contact finger454of the contactor is spaced from the circuit substrate102. The rest position represents a beginning and an end of the actuation movement. It can also be seen that only an end portion of the coupling portion322protrudes from the surface portion of the key tappet220.

FIG. 7shows a partially sectional view of a subsection of a keyboard100according to an embodiment of the present invention with a key module110in the course of an actuation movement. The illustration inFIG. 7corresponds to the illustration fromFIG. 6, except that the key module110is shown at a switching point or in a switching position during the actuation movement. Compared with the rest position, the key tappet220here is moved further into the module housing230, wherein the contact finger454of the contactor contacts the circuit substrate102or the contact pads on the circuit substrate102.

FIG. 8shows a partially sectional view of a subsection of a keyboard100according to an embodiment of the present invention with a key module110in an actuated position. The illustration inFIG. 8corresponds to the illustration fromFIG. 6orFIG. 7, except that the key module110is shown in the actuated position. The actuated position represents a reversal point of the actuation movement. The contact finger454of the contactor continues to contact the circuit substrate102or the contact pads on the circuit substrate102. Between the switching position of the key module110illustrated inFIG. 7and the actuated position of the key module110illustrated inFIG. 8frictional contact or contact with a frictional component between the contact finger454and the contact pads of the circuit substrate102takes place.

In other words,FIGS. 6 to 8show at different phases of a switching process or the actuation movement. It is an advantage of the switching mechanism or contactor that in the course of the actuation movement the contact fingers454increasingly build up a contact force and additionally perform a rubbing movement along a plane of the circuit substrate102, thereby achieving a self-cleaning effect. The contact zones or contact pads on the circuit substrate102may additionally be protected by way of a contact grease, which prevents oxidation and minimizes wear of contact parts.

FIG. 9shows a partially sectional view of a subsection of a keyboard100according to an embodiment of the present invention with a key module110in a rest position. The subsection of the keyboard100corresponds to the subsection illustrated inFIG. 2, wherein the key module110is arranged on the circuit substrate102and the fixing element is omitted. Thus, the illustration inFIG. 9is similar to the illustration fromFIG. 5orFIG. 6, except that a sectional plane is changed. InFIG. 9, the circuit substrate102and the key module110are shown of the keyboard100, wherein the key tappet220with the coupling portion322, the surface portion326, the guiding stud328and the intermediate bottom529, the module housing230with the positioning protrusion334and the actuation cam539, the elastic means340and the control cam466of the contactor are shown of the key module110. If the rest position, the control cam466of the clapper or second leg of the contactor is not in contact with the actuation cam539of the module housing230or is spaced therefrom. The actuation cam539extends from a switch bottom of the module housing230along an axis of the actuation movement in the direction of the key tappet220and has a defined contour.

FIG. 10shows a partially sectional view of a subsection of a keyboard100according to an embodiment of the present invention with a key module110in a pre-actuated state. The illustration inFIG. 10corresponds to the illustration fromFIG. 9, except that the key module110is shown in the course of the actuation movement in the pre-actuated state after leaving the rest position. Here, the control cam466of the contactor contacts the actuation cam539of the module housing230or has come into mechanical contact therewith.

FIG. 11shows a partially sectional view of a subsection of a keyboard100according to an embodiment of the present invention with a key module110at a click point. The illustration in inFIG. 11corresponds to the illustration fromFIG. 10, except that the key module110is shown in a further course of the actuation movement after the pre-actuated state at the click point. Upon further actuation, a tip of the actuation cam539slides over a contour or slope of the control cam466. Owing to relative angles and friction between the two parts, the clapper or the second leg of the contactor is elastically deflected in the direction away from the circuit substrate102until striking in the opening of the contactor. At the same time, elastic deflection of the clapper or second leg towards the first leg occurs until a tip of the actuation cam539is over a tip of the control cam466this estate is referred to as the click point. The click point can be influenced exactly or defined and/or changed accurately by way of a position of the actuation cam539.

FIG. 12shows a partially sectional view of a subsection of a keyboard100according to an embodiment of the present invention with a key module110in a feedback position. The illustration inFIG. 12corresponds to the illustration fromFIG. 11, except that the key module110is shown in a further course of the actuation movement after the click point in the feedback position. After the click point, the clapper or second leg of the contactor is suddenly released and moves within the opening of the contactor to a stop on a lower edge of the opening facing the circuit substrate102. Thereby, a sound or acoustic feedback, which is referred to as a clicking sound, is produced.

Sound volume depends on stored energy in the defection portion of the contactor, which is referred to as click mechanism or click spring. An amount of energy can be adjusted via a length of the opening formed as an elongated hole or via a cross-section and/or a length of the defection portion.

It is possible to synchronize an electric switch point of the key module110with the click point, or to arbitrarily adjust the same before or after the electric switch point. Contours of the control cam466and of the actuation cam539also influence a force-displacement characteristic of the key module110in the actuation movement. According to the embodiment illustrated here, a pressure point synchronized with the acoustic click point forms the tactile feedback. Precision and thus reproducibility of the acoustic feedback can be increased because the substantial components of the click mechanism are realized in the contactor and thus in a single component.

FIG. 13shows a partially sectional view of a subsection of a keyboard100according to an embodiment of the present invention with a key module110in an actuated position. The illustration inFIG. 13corresponds to the illustration fromFIG. 12, except that the key module110is shown in a further course of the actuation movement in the actuated position or at a reversal point of the actuation movement.

FIG. 14shows a bottom view of a key module110according to an embodiment of the present invention. A subsection of the key tappet220, the module housing230with the positioning protrusion334, the mounting portion336and the flange338, as well as the contact fingers454of the contactor are shown of the key module110. Two cutouts are formed in a bottom portion of the module housing230directable toward the circuit substrate. Through one of the cutouts, the contact fingers454of the contactor come into contact with the circuit substrate for shorting the contact pads. Through the other one of the cutouts, the key module110can be eliminated by means of a light-emitting diode on the circuit substrate, particularly from the inside or via an inside of the key module110.

FIG. 15shows a schematic bottom view of a subsection of the key module according to an embodiment of the present invention. In the illustration ofFIG. 15, the trigger element350with for example only two contact fingers454and an abutment surface1531of the module housing are shown of the key module. The key module inFIG. 15corresponds to the key module from one of the previously described figures, except that the module housing comprises the abutment surface1531. The abutment surface1531is formed and arranged so that the trigger element350is arranged so as to abut on the abutment surface1531in the rest position of the key tappet of the key module.

According to the embodiment illustrated here, one of the contact fingers454is arranged so as to abut on the abutment surface1531in the rest position of the key tappet of the key module. To this end, the trigger element350has a rest portion1555on the contact fingers454in question. In the rest position there is mechanical contact between the rest portion1555and the abutment surface1531. In other words, the rest portion1555abuts on the abutment surface1531in the rest position.

By the trigger element350or the contactor abutting on the abutment surface1531as a stop in the rest position, undesired vibrations of the trigger element350, in particular also of the contact fingers454, can be dampened or prevented.

FIG. 16shows a partially sectional view of a subsection of a keyboard according to an embodiment of the present invention with a key module prior to assembly or first-time actuation. The keyboard is the keyboard from one of the previously described figures. The key module corresponds to or resembles the key module fromFIG. 15, wherein inFIG. 16a sidewall of the module housing230with a damper portion comprising the abutment surface1531and an inclined surface1633and the trigger element350with the for example only two contact fingers454and the rest portion1555are shown of the key module and the contact pads203of the circuit substrate are shown of the keyboard.

InFIG. 16, what is shown is a state prior to assembly or first-time actuation of the key module of the keyboard. Prior to the assembly or first-time actuation, the damper portion with the abutment surface1531and the inclined surface1633is arranged between the trigger element350and the contact pads203. The inclined surface1633is formed to enable or cause first-time and non-recurring sliding of the trigger element350. The abutment surface1531may be oriented at an acute angle or parallel to the inclined surface1633. The abutment surface1531at least is formed such that sliding back to the position prior to the assembly or first-time actuation is prevented.

During assembly or first-time actuation of the key module, the trigger element350can be deflected along the inclined surface1633and guided past the damper portion for the first and only time and thus slide past the damper portion. Additionally or alternatively, when the trigger element350is sliding across the inclined surface1633, the damper portion, particularly the inclined surface1633, can be deflected. Thus, in addition to or as an alternative to the trigger element350, also the damper portion may comprise flexible material.

FIG. 17shows a partially sectional view of the subsection of the keyboard fromFIG. 16with the key module in an actuated position. Here, the illustration inFIG. 17corresponds to the illustration fromFIG. 16except for the key module being shown in the actuated position, wherein electric contact is established between contact fingers454and the contact pads203. Here, the contact fingers454and the rest portion1555are arranged between the contact pads203and the damper portion with the abutment surface1531and the inclined surface1633formed on the module housing230. Also, the rest portion1555is spaced from the damper portion, in particular the abutment surface1531, here. Starting from the state illustrated inFIG. 16and moving to the state shown inFIG. 17, the rest portion1555of the trigger element350has slid past on the inclined surface1633and the abutment surface1531for the first and only time.

FIG. 18shows a partially sectional view of the subsection of the keyboard fromFIG. 16orFIG. 17with the key module in a rest position. Here, the illustration inFIG. 18corresponds to the illustration fromFIG. 17, except that the key module is shown in the rest position, wherein the rest portion1555of the trigger element350abuts on the abutment surface1531. Noise due to vibrations of the trigger element350, in particular the contact fingers454, can thus be prevented. The trigger element350, more specifically the rest portion1555, cannot slide back across the damper portion again to reach the state shown inFIG. 16, for example. The rest portion1555engages behind the abutment surface1531, for example.

According to an embodiment and with reference to the previously described figures, in an assembly method for assembling the key module110, the key tappet220with the trigger element350arranged thereon can be inserted into the module housing230. Here, a relative movement of the key tappet220with the trigger element350with respect to the module housing230can be effected along the axis A of the actuation movement. The trigger element350and/or the damper portion or the inclined surface1633also is deflected during this relative movement so that the trigger element350is guided past the damper portion and slides past the damper portion for the first and only time. The relative movement takes place when inserting the key tappet220including the trigger element350to the module housing230at least until the rest position is reached. By the trigger element350abutting on the abutment surface1531, return of the key tappet220or the trigger element350to a position like prior to assembly, seeFIG. 16, is prevented.

If an embodiment comprises an “and/or” connection between a first feature and a second feature, this may be read to mean that the embodiment comprises both the first feature and the second feature according to one embodiment and either only the first feature or only the second feature according to a further embodiment.

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