Patent Description:
This disclosure generally relates to input devices such as switches and keyboards.

To produce a conventional keyboard, the keycaps, printed circuit board (PCB), mechanical springs, switches and the shell are all manufactured separately and need to be assembled after each component is created. Using individual design tools, some of these components can be created using 3D-printing, but there are no means to combine the components other than by assembly and/or other post-processing techniques.

<CIT> discloses a resistive switch which comprises two conduction plates, one of which is resilient so that it may be depressed against the other conductor plate to close the switch. One of the conduction plates comprises a flexible support sheet with a thin conductive layer applied on the surface. The second conductive plate comprises a rigid plastic base member and a thin copper surface disposed thereon. A thin semiconductor layer is applied on either the copper surface, the conductive layer or both.

<CIT> discloses a switch assembly for an electronic device comprising an actuator and opposing contact areas. The deformation of the actuator may allow the opposing contact areas to come into physical contact to close an electrical circuit or allow the contact areas to come closer together to cause a change in state, such as an increase in capacitance.

In general, an aspect of the subject matter described in this specification relates to the use of multi-material 3D-printing (additive manufacturing) to produce durable and attractive finished input devices, such as switches and keyboards, from mixtures of polymers, organic materials, and/or metals. These items can include both mechanical and electrical systems, and the ability to be deformed or deflected during use. In some embodiments, such items can be 3D-printed in a single 3D-printing process run using multi-material 3D-printing processes.

Some aspects described herein include using multi-material 3D printing to create custom input devices by combining inventive aspects such as: (i) custom deformable 3D-printed items, (ii) 3D-printed structural electronics, (iii) 3D printed springs, (iv) 3D-printed enabled interfaces, and/or (v) 3D-printed capacitive touch interfaces. This disclosure describes these advanced manufacturing techniques to design and produce 3D-printed deformable input devices, in one print, without post-processing, and without sacrificing functionality. Alternatively, in some embodiments two or more prints can be used to produce deformable input devices described herein. Multiple non-limiting examples of the inventive disclosure are provided below, including descriptions related to example input devices such as a computer keyboard, gamepad, analog trigger, joystick, and piano keyboard, all respectively manufacture-able in a single 3D-print run. Some such input devices can be 3D-printed to provide a finished item without the need for post-processing or assembly, or requiring only minimal post-processing or assembly.

Currently when a designer or engineer wants to prototype a part with the design properties of the devices described herein, she/he would be required to create multiple component parts and then assemble them once all prints are completed. Prototyping input devices such as those described herein adds another layer of complexity because both mechanical and electrical systems are required, which means relying on multiple manufacturing processes. Creating full devices with fewer parts and with a single manufacturing process can drastically reduce the time and cost it takes to manufacture components and finished devices. Furthermore, being able to 3D-print such devices in a single print process/run further reduces the time and cost, allowing for more design iterations to take place, ultimately leading to a better result.

In one aspect, this disclosure is directed to an electrical input device that includes a non-conductive material portion and a conductive material portion. The non-conductive and conductive material portions are integrally formed using a multi-material 3D-printing process. Deformation of the electrical input device causes an electrical variance through the conductive material portion that is responsive to the deformation. The electrical variance through the conductive material portion comprises closing an electrical circuit formed by the conductive material portion.

Such an electrical input device may optionally include one or more of the following features. The deformation during use of the electrical input device may provide a digital output. The electrical variance through the conductive material portion may include changing a resistance of the electrical circuit formed by the conductive material portion. The electrical variance through the conductive material portion may include changing a capacitance of an electrical circuit formed by the conductive material portion. The deformation during use of the electrical input device may provide an analog output. The analog output may correspond to an extent of the deformation. The analog output may be proportional to an extent of the deformation. The electrical input device may be a switch. The electrical input device may be a key for a computer keyboard. The electrical input device may be a key for a piano keyboard.

The invention is directed to a method of making an electrical input device. The method includes operating a multi-material 3D-printing process to integrally print a non-conductive material portion and a conductive material portion. Deformations of the conductive material portion or non-conductive material portion of the electrical input device during use of the electrical input device cause an electrical variance through the conductive material portion that is responsive to the deformations, wherein the electrical variance through the conductive material portion comprises closing an electrical circuit formed by the conductive material portion.

Such a method of making an electrical input device may optionally include one or more of the following features. The non-conductive material portion may include one or more helical springs. The electrical input device may be a switch. The electrical input device may be a computer keyboard. The electrical input device may be a piano keyboard.

The details of one or more implementations are set forth in the accompanying drawings and the description, below. Other potential features and advantages of the disclosure will be apparent from the description and drawings, and from the claims.

Referring to <FIG>, three different example types of individual keys for a computer keyboard that can be created using the materials and techniques described herein are depicted. That is, as described further below, the depicted keys can be multi-material 3D printed such that they include a conductive material portion that is integrated with a non-conductive material portion. Accordingly, the depicted multi-material 3D printed keys are monolithic or unitary members comprised of at least two different materials.

The depicted keys are designed to be depressed (like a typical computer keyboard) to activate the key. When the keys are depressed to activate the keys, a portion of the key elastically deflects (like a cantilever spring). The keys rebound to the depicted configurations after being activated. The deflectable portions are integral portions of the monolithic keys. In other words, no separate springs are required as with a conventional computer keyboard. This advantageously eliminates or reduces the need for assembling a computer keyboard product after 3D-printing.

These three example keys are different from each other at least in terms of the travel distance, or the key depression distance, required to activate each of the keys. Input device structural parameters, such as key depression distance, can be customized to provide input devices with desired types of performance and/or functionality. In addition to the key depression distance, other parameters can be strategically selected to customize the performance and/or functionality of the keys. For example, such parameters can include material selection (e.g., traditional PLA, carbon-composite PLA, copper composite polyester, ABS, PET, PETG, PTFE, Nylon, TPU PVA, etc.), wall thickness and other part geometry (cross-sectional shapes), print orientation, print speed, infill pattern, and infill print percentage (density), without limitation. Accordingly, the material properties of the final object can be customized and finely tuned instead of only relying on the material it is made from. Such parameters can have significant effects on the mechanical properties of the 3D-printed keys (and the other 3D-printed members described below).

Broadly, metamaterials and compliant mechanisms are a new class of 3D printed objects where the material properties of the component are defined by the internal geometry and structure of the object, and not by the material itself. Metamaterial assemblies allow for a single part to have multiple mechanical properties in the same print. Because of this, full products can be printed in one print reducing the need for assembling a product after printing.

In addition, new materials enable 3D printed electronics. These materials allow for 3D prints to act as sensors, transmitters, and conductive traces without the need for additional electronics minimizing the number of components required, assembly time, weight, and cost.

Referring also to <FIG>, an example computer keyboard key <NUM> can be constructed of two materials using a multi-material 3D-printing process. For example, in the depicted embodiment the key <NUM> comprises or consists of a non-conductive material <NUM> and an electrically conductive material <NUM>. The non-conductive material <NUM> and the electrically conductive material <NUM> are integrated with each other as a result of the use of a multi-material 3D-printing process to create the key <NUM>.

In the depicted embodiment, the flexible portion of the key <NUM> is wholly made of the electrically conductive material <NUM>. In particular, the flexible portion 120a is made of the electrically conductive material <NUM>. In addition, the electrically conductive material <NUM> makes up the two contact portions 120b and 120c. The flexible portion 120a elastically deflects and the conductive contact portions 120b and 120c physically contact each other when the key <NUM> is depressed sufficiently. The physical abutment between the conductive contact portions 120b and 120c closes an electrical circuit and thereby functionally indicates that the key <NUM> is activated. This provides a digital output signal (on or off) from the key <NUM>.

While in the depicted example key <NUM> the flexible portion 120a is made entirely of the electrically conductive material <NUM>, such a construction is not required in all embodiments. For example, as described below in reference to the example of <FIG>, many other variations are possible and are within the scope of this disclosure.

<FIG> illustrate an example computer keyboard <NUM> that can be multi-material 3D-printed in a singular print run to create a fully functional QWERTY keyboard without the need for assembly and/or other post-processing. The computer keyboard <NUM> (<FIG>) includes an electrically conductive material portion <NUM> (shown in isolation in <FIG>) that is integrated during the 3D-printing process with a non-conductive material portion <NUM> (shown in isolation in <FIG>). The non-conductive material portion <NUM> and the electrically conductive material portion <NUM> are shown separately in <FIG>, but that is only for the purpose of facilitating an understanding of how each of those portions are integrally combined to make up the actual 3D-printed computer keyboard <NUM> shown in <FIG>.

The computer keyboard <NUM> is constructed of multiple keys <NUM> (<FIG>). Each of the keys <NUM> includes a non-conductive material <NUM> and an electrically conductive material <NUM>.

To confirm the concepts described herein, the inventors constructed an actual computer keyboard <NUM> using a multi-material 3D-printing process. <FIG> is an in-process illustration of the example computer keyboard <NUM> being multi-material 3D-printed. <FIG> shows the final resulting computer keyboard <NUM> that was created by the multi-material 3D-printing process. The process included the integral 3D-printing of the non-conductive material portion <NUM> of <FIG> and the conductive material portion <NUM> of <FIG> using the materials and techniques described herein.

Referring to <FIG>, an example piano key <NUM> can be produced using the techniques described herein. The piano key <NUM> is shown in a side view. The piano key <NUM> comprises or consists of a non-conductive material portion <NUM> and an electrically conductive material portion <NUM>. The non-conductive material <NUM> and the electrically conductive material <NUM> are integrated with each other as a result of the use of a multi-material 3D-printing process to create the piano key <NUM>.

In the depicted example embodiment, the flexible portion of the key <NUM> is wholly made of the non-conductive material <NUM>. In particular, the flexible portion 310a is made of the non-conductive material <NUM>.

The electrically conductive material <NUM> makes up three contact portions 320b, 320c, and 320d (<FIG>). The flexible portion 310a elastically deflects and the conductive contact portions 320b, 320c, and 320d physically and electrically connect with each other when the key <NUM> is depressed sufficiently.

Referring also to <FIG>, as can be envisioned, the physical contact between the conductive contact portion 320b and the conductive contact portions 320c, and 320d closes an electrical circuit between the two separate traces of the electrically conductive material <NUM> that make up the contact portions 320c and 320d. That is, when the piano key <NUM> is depressed, the conductive contact portion 320b physically bridges and electrically connects the two separate contact portions 320c and 320d to thereby functionally indicate that the piano key <NUM> is activated. This opening or closing of the circuit between the two separate contact portions 320c and 320d provides a digital output signal (on or off) from the piano key <NUM>.

While in the depicted example piano key <NUM> the flexible portion 310a is made entirely of the electrically non-conductive material <NUM>, such a construction is not required in all embodiments. For example, as described above in reference to the example of <FIG>, many other variations are possible and are within the scope of this disclosure.

<FIG> illustrate an example piano keyboard <NUM> that can be multi-material 3D-printed in a singular print run with both its mechanical and electrical systems (not including the processor) to create a fully functional piano keyboard with only a minimal need for assembly and/or other post-processing. The piano keyboard <NUM> includes an electrically conductive material portion <NUM> (shown in isolation in <FIG>) that is integrated during the 3D-printing process with a non-conductive material portion <NUM> (shown in isolation in <FIG>). The non-conductive material portion <NUM> and the electrically conductive material portion <NUM> are shown separately in <FIG>, but that is only for the purpose of facilitating an understanding of how each of those portions are integrally combined to make up the actual 3D-printed computer keyboard <NUM> shown in <FIG>.

The piano keyboard <NUM> is constructed of multiple piano keys <NUM> (<FIG>). Each of the keys <NUM> includes a non-conductive material portion <NUM> and an electrically conductive material portion <NUM>.

To confirm the concepts described herein, the inventors constructed one octave of an actual piano keyboard <NUM> using a multi-material 3D-printing process. <FIG> is an in-process illustration of the example piano keyboard <NUM> being multi-material 3D-printed. <FIG> shows the final resulting piano keyboard <NUM> that was created by the multi-material 3D-printing process. The process included the integral 3D-printing of the non-conductive material portion <NUM> of <FIG> and the conductive material portion <NUM> of <FIG> using the materials and techniques described herein. The result was a fully functional piano keyboard <NUM> that did not require any additional assembly, and only required the removal of support material for post-processing.

Referring to <FIG>, an example switch <NUM> can be constructed of two materials using a multi-material 3D-printing process. For example, in the depicted embodiment the switch <NUM> comprises or consists of a non-conductive material portion <NUM> and an electrically conductive material portion <NUM>. The non-conductive material <NUM> and the electrically conductive material <NUM> are integrated with each other as a result of the use of a multi-material 3D-printing process to create the switch <NUM>.

In the depicted embodiment, the flexible portion of the switch <NUM> is wholly made of the electrically conductive material <NUM>. In particular, the flexible portion 520a is made of the electrically conductive material <NUM>. In addition, the electrically conductive material <NUM> makes up the two contact portions 520b and 520c. The flexible portion 520a elastically deflects and the conductive contact portions 520b and 520c physically contact each other when the switch <NUM> is depressed sufficiently. The physical abutment between the conductive contact portions 520b and 520c closes an electrical circuit and thereby functionally indicates that the switch <NUM> is activated. This provides a digital output signal (on or off) from the switch <NUM>.

While in the depicted example switch <NUM> the flexible portion 520a is made entirely of the electrically conductive material <NUM>, such a construction is not required in all embodiments. For example, as described above in reference to the example of <FIG>, many other variations are possible and are within the scope of this disclosure.

The example switch <NUM> can be used in a great number of different contexts and devices. For example, <FIG> depicts an example controller <NUM> that includes multiple individual switches <NUM>. As shown in the illustration of <FIG>, the inventors actually constructed the example controller <NUM> using a multi-material 3D-printing process. The process consisted of the integral 3D-printing of the non-conductive material portion <NUM> of <FIG> and the conductive material portion <NUM> of <FIG> using the materials and techniques described herein. The result was the fully functional controller <NUM> that did not require any additional assembly or post-processing.

Referring to <FIG>, in addition to the digital input devices described above, the inventive concepts described herein can also be employed to create deformable analog input devices. For example, an example analog input device <NUM> has been designed and multi-material 3D-printed. The analog input device <NUM> comprises or consists of a non-conductive material portion <NUM> (shown in isolation in <FIG>) and an electrically conductive material portion <NUM> (shown in isolation in <FIG>). The non-conductive material portion <NUM> and the electrically conductive material portion <NUM> are integrated with each other (as shown in <FIG>) as a result of the use of a multi-material 3D-printing process to create the analog input device <NUM>.

The non-conductive material portion <NUM> of the analog input device <NUM> includes a thin non-conductive depressible surface 710a that is attached to an elastically deformable double helical spring 710b. The electrically conductive material portion <NUM> of the analog input device <NUM> includes an electrode 720a positioned normal to the travel axis of the depressible surface 710a. In this configuration, as a user presses her/his finger on the depressible surface 710a, the user has fine control over how close her/his finger is positioned to the electrode 720a.

As the depressible surface 710a is pushed/moved by the user toward the electrode 720a, the electrode 720a records a change in capacitance in correspondence to the distance between the user's finger (which is in contact with the depressible surface 710a) and the electrode 720a. That capacitance can be measured to provide an indication of the distance between the depressible surface 710a (while in contact with the user's finger) and the electrode 720a.

<FIG> shows some examples of how design parameters of the analog input device <NUM> can be strategically selected to provide the performance characteristics of the analog input device <NUM> that are desired. In particular, the analog input device 700a has a short travel distance, the analog input device 700b has a medium travel distance, and the analog input device 700c has a long travel distance. These differences are the result of differing lengths of the deformable double helical springs. It can be envisioned that other aspects of the analog input device <NUM> can similarly be strategically selected to provide differing performance characteristics of the analog input device <NUM>. For example, the spring constant or stiffness of the deformable double helical spring can be strategically selected to provide differing performance characteristics of the analog input device <NUM>.

Claim 1:
A method of making an electrical input device (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), the method comprising operating a multi-material 3D-printing process to integrally print a non-conductive material portion (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>,<NUM>) and a conductive material portion (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>),
wherein deformations of the conductive material portion or the non-conductive material portion of the electrical input device during use of the electrical input device cause an electrical variance through the conductive material portion that is responsive to the deformations, wherein the electrical variance through the conductive material portion comprises closing an electrical circuit formed by the conductive material portion.