Patent Description:
As the desire to create three-dimensional (3D) models outside of a lab or factory environment grows, such as in the field or in-situ situations, 3D printing pens have become more useful. Conventional 3D printing pens have generally been designed to deliver mono-pigment models. For example, <CIT> describes a 3D printing pen for extruding and curing a radiation-curable pasty polymer composition that delivers mono-pigment models. Such conventional 3D printing pens are generally deficient for creating 3D color models because a user is required to insert a color cartridge into the 3D printing pen, perform the desired creative aspects with that pen, then remove that color cartridge in order to insert another different color cartridge. Such 3D printing pens and methods of delivery are time consuming and lack the ability to efficiently generate robust 3D models.

International patent application <CIT> describes systems and methods for the formation of three-dimensional objects. Substrates may be formed using the materials, processes, methods, and systems described therein.

International patent application <CIT> describes a system for manufacture of a multi-colored three-dimensional object, comprising at least one tank configured to store a colorless pseudoplastic material at atmospheric pressure, at least one bidirectional pump, an extrusion nozzle having at least one opening and configured to draw thereinto at least a quantity of the color materials and/or colorless pseudoplastic material and extrude in image-wise manner the drawn material and a X-Y-Z movement system configured to move at least the extrusion nozzle in a three coordinate system wherein the extrusion nozzle draws and extrudes the pseudoplastic material through the same opening.

Chinese patent application <CIT> describes a colorful 3D printing pen comprising a printing pen body; a first stepping motor arranged at the top of an inner cavity of the printing pen body; a support fixedly arranged at the bottom of the first stepping motor; a second stepping motor arranged at the bottom of the support; an L-shaped rod connected to the bottom end of the second stepping motor; a pressure air pump arranged at the bottom of the second stepping motor; cartridge sets arranged at the bottom of the pressure air pump; a stirring guide rod arranged between the cartridge sets and penetrating through the pressure air pump to be connected to the second stepping motor; pressure valve switches arranged on one sides of the tops of the cartridge sets and connected to the tail end of the L-shaped rod in a clamped mode; a single chip microcomputer arranged on one sides of the cartridge sets; a bluetooth arranged at the bottom of the single-chip microcomputer; a gyroscope arranged at the bottom of the bluetooth; and a pen point arranged at the bottoms of the cartridge sets.

<CIT> discloses a three-dimensional printing pen with a single ink cartridge.

The present disclosure provides various embodiments of 3D printing pens and systems and methods related thereto that allow a user to produce multiple colors in production of a 3D model while not requiring the user to insert a different color cartridge at the point at which a new color is desired. Further, various embodiments of the 3D printing pens and system and methods related thereto described herein allow multiple colors to be used within a 3D printing pen while avoiding colors being extruded from the 3D printing pen from bleeding into previously extruded colors.

According to a first aspect there is provided a three-dimensional printing pen including a plurality of cartridges, each cartridge having a hollow cartridge body including a colored thixotropic paste, a color of each thixotropic paste being different from a color of another thixotropic paste, and a plurality of nozzles, each nozzle fluidly communicatively coupled to a corresponding cartridge. The three-dimensional printing pen further includes a motor unit operably coupled to the plurality of cartridges, the motor unit operable to expel the colored thixotropic paste from each cartridge through the corresponding nozzle, a mixing tip fluidly communicatively coupled to the plurality of nozzles, the mixing tip sized and shaped to dispense therethrough one or more of the colored thixotropic pastes in a form of an output thixotropic paste, a projection module, and a housing. The projection module has a light engine assembly that emits light having a wavelength, the light being projected to the output thixotropic paste to cure the output thixotropic paste that is dispensed from the mixing tip. The housing at least partially houses each of the plurality of cartridges, the plurality of nozzles, the motor unit, the mixing tip and the projection module.

In another not claimed example, non-limiting embodiment or implementation, a three-dimensional printing system can be summarized as including a three-dimensional printing pen that includes a plurality of cartridges, each cartridge having a hollow cartridge body sized and shaped to include a colored thixotropic paste, a color of each thixotropic paste being different from a color of another thixotropic paste, a plurality of nozzles, each nozzle fluidly communicatively coupled to a corresponding cartridge, and a mixing tip fluidly communicatively coupled to the plurality of nozzles, the mixing tip sized and shaped to dispense therethrough one or more of the colored thixotropic pastes in a form of an output thixotropic paste. The three-dimensional printing system can include a dispensing apparatus having a motor unit, a projection module having a light engine assembly, and control circuitry that is communicably coupled to the three-dimensional printing pen, the dispensing apparatus, and the projection module, the control circuitry. The control circuitry can generate one or more signals indicative of a color of the output thixotropic paste, generate one or more signals to cause the motor unit to expel the colored thixotropic paste from each cartridge through the corresponding nozzle to substantially match the color of the output thixotropic paste, and generate one or more signals to cause the projection module to emit light from the light engine assembly at a wavelength which cures the output thixotropic paste to form a desired object.

According to a further aspect there is provided a method including receiving, by at least one microprocessor, one or more signals at a three-dimensional printing pen, identifying a color of an output thixotropic paste, in response to the receiving the one or more signals at the three-dimensional printing pen, dispensing, by the at least one microprocessor, one or more colored thixotropic pastes that substantially match the color of the output thixotropic paste, the one or more colored thixotropic pastes being dispensed from one or more of a plurality of cartridges, each including a differently colored thixotropic paste, through one or more nozzles corresponding to and fluidly communicatively coupled to the one or more cartridges, and through a mixing tip fluidly communicatively coupled to the one or more nozzles, and causing, by the at least one microprocessor, a projection module to emit a light having a wavelength which cures the output thixotropic paste to form an object wherein the three dimensional printing pen comprises the plurality of cartridges, the one or more nozzles, the motor unit, the mixing tip, the projection module, the microprocessor, and a housing that at least partially houses the plurality of cartridges, the one or more nozzles, the motor unit, the mixing tip, the projection module and the microprocessor.

Reference throughout this specification to "one embodiment," "one implementation," "an embodiment," or "an implementation" means that a particular feature, structure or characteristic described in connection with the embodiment or implementation is included in at least one embodiment or one implementation. Thus, the appearances of the phrases "in one embodiment," "in one implementation," "in an implementation," or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment or implementation. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments or implementations.

In the following description, certain specific details are set forth in order to provide a thorough understanding of various embodiments or implementations. However, one skilled in the art will understand that the embodiments or implementations may be practiced without these details. In other instances, well-known structures associated with 3D printing pens, gears, motors, and related systems and methods have not been described in detail to avoid unnecessarily obscuring the descriptions of the embodiments or implementations.

Unless the context requires otherwise, throughout the specification and claims which follow, the word "comprise" and variations thereof, such as "comprises" and "comprising" are to be construed in an open sense, that is, as "including, but not limited to.

<FIG> illustrates a conventional 3D printing pen <NUM>. The conventional 3D printing pen <NUM> includes a channel <NUM> having a photopolymer stored therein and an extruder <NUM>. In use, the photopolymer stored therein is heated and extruded from the conventional 3D printing pen <NUM>. Upon exposure to a light source, the photopolymer hardens into the desired shape. The conventional 3D printing pen <NUM>, however, fails to describe, among other things, the functionality or the structure capable of dispensing multiple colors through the extruder <NUM> concurrently while the conventional 3D printing pen <NUM> is in use.

<FIG> illustrate a 3D printing pen <NUM>, according to one example, non-limiting embodiment, that is capable of dispensing thixotropic paste(s) of multiple colors simultaneously, dynamically mixing the thixotropic paste(s) of multiple colors at suitable and/or desired ratios, and/or curing the dispensed material to form a desired three-dimensional object, among other things described in more detail below.

The 3D printing pen <NUM> includes a controller <NUM>, a plurality of cartridges 12a, 12b, 12c, 12d, 12e (collectively referred to herein as cartridge <NUM>), a dispensing apparatus <NUM>, a dynamic mixing apparatus <NUM>, and an end cap assembly <NUM>. Although shown only partially in <FIG>, the 3D printing pen <NUM> includes a housing <NUM> that is sized and shaped to house, either fully or in part, each of the components of the 3D printing pen <NUM>. Each cartridge <NUM> includes a cartridge body <NUM> (e.g., cartridge body 19a, 19b, 19c, 19d, 19e, collectively or individually referred to as cartridge body <NUM>) that is sized and shaped to hold therein one or more colored thixotropic photopolymer paste(s) <NUM>, and a cartridge nozzle <NUM> (e.g., cartridge nozzle 20a, 20b, 20c, 20d, 20e, collectively or individually referred to as cartridge nozzle <NUM>) that is sized and shaped to dispense the one or more colored thixotropic paste(s) <NUM>. In one embodiment, the 3D printing pen <NUM> may employ a CMYKW color model under which one cartridge body <NUM>, e.g., cartridge body 19a, may include a cyan colored thixotropic photopolymer paste <NUM>; one cartridge body <NUM>, e.g., cartridge body 19b, may include a magenta colored thixotropic photopolymer paste <NUM>; one cartridge body <NUM>, e.g., cartridge body 19c, may include a yellow colored thixotropic photopolymer paste <NUM>; one cartridge body <NUM>, e.g., cartridge body 19d, may include a white colored thixotropic photopolymer paste <NUM>; and one cartridge body <NUM>, e.g., cartridge body 19d, may include a key or black colored thixotropic photopolymer paste <NUM>. It should be understood, upon review of the present disclosure, that the reference numeral <NUM> may individually refer to any one of the different colored thixotropic pastes described herein, including cyan, magenta, yellow, key or black, or white colored thixotropic pastes.

In some embodiments, one or more cartridges <NUM> including cyan, magenta, yellow, white, and/or key or black colored thixotropic photopolymer paste <NUM> may be omitted or excluded. For example, in some embodiments the 3D printing pen <NUM> may include cartridges for dispensing colored thixotropic pastes <NUM> representing cyan, magenta, yellow, and black colored pastes only. Again, in other embodiments, any one of the cartridges <NUM> comprising various other colored thixotropic pastes <NUM> may be included or omitted.

The one or more colored thixotropic paste(s) <NUM> may include, in some embodiments, a liquid photopolymer resin, a thixotropic filling agent, an ultraviolet (UV) curing ink, or any combination thereof. For example, the liquid photopolymer resin may comprise a mixture of multi-functional monomers and oligomers that are combined to achieve a desired physical property. Suitable photopolymer resins may include, for example, various resins described in <CIT> and <CIT>. In some embodiments, suitable photopolymers may comprise polyether methyl acrylate-based materials.

In some embodiments, the thixotropic filling agent may include fumed silica, sold under the tradenames of Cab-O-Sil® or Aerosil®. In some embodiments, the thixotropic filling agent may comprise linear sulfated polysaccharides extracted from red edible seaweeds, such as carrageenans. In some embodiments, the thixotropic filling agent may comprise a synthetic water-soluble polymer, such as a hydrogel. In some embodiments, the water-soluble polymer may comprise liquid or solid PEG gel. In some embodiments, the colored thixotropic paste <NUM> may further include milled glass fiber or other suitable materials to improve strength, dimensional stability, and/or increase elastic modulus. In some embodiments, any combination of the various thixotropic filling agents may be included in the one or more colored thixotropic paste(s) <NUM>.

The Ultraviolet (UV) curing ink may comprise reactive monomers, photo initiators, oligomers, suitable pigments and additives that, when exposed to UV light, for example, create a rigid, extruded 3D shape or structure. In some embodiments, the composition of the one or more colored thixotropic paste(s) <NUM> may include UV curing ink at approximately <NUM>% by weight. In other embodiments, other weight percentages of the UV curing ink may be selected based on desired outcomes.

As illustrated in <FIG> in more detail, each cartridge <NUM> is radially spaced apart from each other about a central axis <NUM> of the 3D printing pen <NUM>. In some embodiments, the angular spacing of each cartridge <NUM> may be equal or unequal. Each cartridge nozzle <NUM> extends from an end of the respective cartridge body <NUM> and is sized and shaped to taper down from the end of the cartridge body <NUM> terminating in a cartridge tip <NUM>. The cartridges <NUM> are each coupled, at least in part, to a dispensing apparatus <NUM> via a mounting plate <NUM>. In general, the dispensing apparatus <NUM> is communicatively coupled to the controller <NUM> and configured and/or operable to dispense the one or more colored thixotropic paste(s) <NUM> to the dynamic mixing apparatus <NUM>, as described in more detail below.

The dispensing apparatus <NUM> includes a motor unit <NUM>. The motor unit <NUM>, in some embodiments, may include one or more stepper motors <NUM> (e.g., stepper motors 29a, 29b, 29c, 29d, 29e, collectively or individually referred to as stepper motor <NUM>) coupled to each cartridge <NUM>. As shown in more detail in <FIG>, each of the one or more stepper motors <NUM> may be coupled with a lead screw <NUM> for example via a coupling <NUM>, as shown in more detail in <FIG>. The lead screw <NUM> is received in the cartridge body <NUM> and is coupled to a plunger <NUM>. Thus, as the one or more stepper motor <NUM> rotates, such rotation drives the lead screw <NUM> in an axial direction, indicated by arrow X. As described above, the lead screw <NUM> is coupled to the plunger <NUM>. As the lead screw <NUM> is driven, such causes axial movement of the plunger <NUM>. The plunger <NUM> includes a head or a plunger seal that sealingly engages with an interior surface of the cartridge body <NUM> to dispense or expel the colored thixotropic paste <NUM> through the cartridge nozzle <NUM>. In particular, proximal movement of the plunger <NUM> may create a positive pressure in the cartridge body <NUM> to expel or dispense the colored thixotropic paste <NUM>.

While in one embodiment illustrated in <FIG>, the motor unit <NUM> includes stepper motors <NUM>, in other embodiments, the motor unit <NUM> may include a DC motor, solenoid, relay or some other electromechanical or magnetic actuator that may drive or axially move the plunger <NUM> in order to expel or dispense the color thixotropic paste <NUM>.

As described above, the dispensing apparatus <NUM> is coupled, at least in part, to the cartridges <NUM> via mounting plate <NUM>. In particular, the mounting plate <NUM> is coupled to the stepper motors <NUM> via the coupling <NUM>. The mounting plate <NUM> includes a plurality of coupling apertures <NUM> that are radially spaced apart about the central axis <NUM>. Each coupling aperture <NUM> is sized and shaped to receive therethrough the coupling <NUM>. Each coupling <NUM> is generally hollow and sized and shaped to coupleably receive a head of the lead screw <NUM> and an output shaft <NUM> of the stepper motor <NUM>.

Each cartridge <NUM> is coupled to the dynamic mixing apparatus <NUM>, wherein the dynamic mixing apparatus <NUM> is communicatively coupled to the controller <NUM> and, generally, selectively dynamically mixes, blends, and/or distributes the different colored thixotropic pastes <NUM>. In particular, as shown in more detail in <FIG>, the dynamic mixing apparatus <NUM> includes a mixing rotor <NUM>, a rotor hub <NUM>, a rotor housing <NUM>, mixing tip <NUM>, and a mixing housing <NUM>. The rotor hub <NUM> includes a plurality of coupling members <NUM> that protrude outwardly from an exterior surface. Each coupling member <NUM> is radially spaced from apart from each other about the central axis <NUM>. Each coupling member <NUM> includes an aperture <NUM> extending therethrough. The aperture <NUM> is sized and shaped to coupleably receive therethrough a corresponding cartridge nozzle <NUM>, which fluidly communicatively couples the rotor hub <NUM> and, more generally, the dispensing mixing apparatus <NUM> to the dynamic mixing apparatus <NUM>, to fluidly receive the color thixotropic paste <NUM>. The rotor hub <NUM> further includes a plurality of radially spaced apart channels <NUM>. Each channel <NUM> extends from the aperture <NUM> radially toward a center of the rotor hub <NUM>. In this manner, the channel <NUM> is fluidly communicatively coupled to the cartridge nozzle <NUM> via the aperture <NUM>.

In or around a center of the rotor hub <NUM>, a shaft aperture <NUM> extends therethrough. The shaft aperture <NUM> is sized and shaped to receive therethrough the mixing rotor <NUM>. In particular, the mixing rotor <NUM> includes a mixing rotor shaft <NUM> coupled to a plurality of radially spaced apart mixing blades <NUM>. The mixing rotor <NUM> is coupled to a mixer motor unit <NUM>. The mixer motor unit <NUM> is communicatively coupled to the controller <NUM>, and is generally selectively configured and/or operable to drive and/or rotate the mixing rotor shaft <NUM> and, consequently, the mixing blades <NUM> to mix, blend, and/or distribute the color thixotropic pastes <NUM>. In particular, in some embodiments the mixer motor unit <NUM> may comprise a brushed DC gear motor having a wide range of gear ratios, for example, from <NUM>:<NUM> to <NUM>:<NUM>. In particular, the gear ratios may be selected based on the desired output torques.

In some embodiments, the mixer motor unit <NUM> may have an integral controller or may be operably coupled to an external controller, such as, for example, controller <NUM>, that includes a pulse width modulation (PWM) controller or module, for example. PWM is a modulation technique that controls the width of a control pulse based on modulator signal information. For example, the PWM controller or module may be operable with a variable speed and/or torque electric motor. In one embodiment, the PWM controller or module may operate by driving the mixer motor unit <NUM> with a series of ON and OFF pulses and varying a duty cycle, i.e., a fraction of time that an output voltage is ON compared to when the output voltage is OFF, of the series of pulses while a frequency constant. As an example, the power applied to the mixer motor unit <NUM> may be controlled by varying a width of the series of applied pulses, which may vary an average DC voltage applied to motor terminals. Thus, by modulating timing of the series of pulses, a speed, i.e., RPM, of the mixer motor unit <NUM> may be selectively controlled. In other words, the longer the pulse is ON, the faster the mixer motor unit <NUM> may rotate. Conversely, the shorter the pulse is ON, the slower the mixer motor unit <NUM> may rotate.

In some embodiments, the mixer motor unit <NUM> may be selected to operate at low PWM frequencies, which may maximize or optimize the output torque. For example, the PWM frequency of the PWM controller of the mixing motor unit <NUM> may be set at <NUM> hertz (Hz).

As described above, the mixer motor unit <NUM> includes a plurality of gears <NUM> that are sized and shaped to provide a wide range of gear ratios from between <NUM>:<NUM> to <NUM>:<NUM>. The mixer motor unit <NUM> includes a mixer motor shaft <NUM> whose output is controlled by the gears <NUM>. The mixer motor shaft <NUM> is coupled to the mixing rotor <NUM>, in particular, the mixing rotor shaft <NUM>, via a mixer coupler <NUM>. Thus, the mixer motor unit <NUM> controllably drives the mixing rotor <NUM> by rotatably moving the mixing rotor shaft <NUM> via the mixer motor shaft <NUM>.

The mixer motor unit <NUM> is positioned between the radially spaced apart cartridges <NUM>. In particular, the mixer motor unit <NUM> is coupled to the cartridges <NUM> via a mixer mounting plate <NUM>. The mixer mounting plate <NUM> includes a plurality of radially spaced apart cartridge apertures <NUM>. Each cartridge aperture <NUM> is sized and shaped to coupleably receive the cartridge body <NUM>, such that the cartridge nozzle <NUM> protrudes outwardly beyond the cartridge aperture <NUM>. Proximal to a center of the mixer mounting plate <NUM>, a central recess <NUM> is provided which extends to a mixer bracket <NUM>. At least a portion of the mixer motor unit <NUM> extends through the central recess <NUM> and is secured or mounted to the mixer bracket <NUM>. As illustrated in detail in <FIG> and <FIG>, for example, the mixing motor shaft <NUM> coupled to the mixing rotor shaft <NUM> via the mixer coupler <NUM> is centrally positioned relative to the radially spaced apart coupling members <NUM> of the rotor hub <NUM>. The rotor hub <NUM> may include one or more hub flanges <NUM> that may be sized and shaped to couple to the housing <NUM> (shown only partially for clarity of description and illustration) of the 3D printing pen <NUM>. The rotor hub <NUM> further includes a plurality of radially spaced apart coupling apertures <NUM>. The coupling apertures <NUM> are sized and shaped to align with a plurality of rotor housing apertures <NUM> disposed in the rotor housing <NUM>. In this manner, the rotor hub <NUM> may be coupled to the rotor housing <NUM> via fasteners (not shown for the sake of clarity of illustration and description).

The rotor housing <NUM> includes a plurality of mixer apertures <NUM> that are positioned proximal to a rotor aperture <NUM> that is sized and shaped to receive the mixing rotor shaft <NUM> therethrough. In particular, the mixer apertures <NUM> are radially spaced apart about the central axis <NUM> of the 3D printing pen <NUM> about which the mixing rotor shaft <NUM> extends. Each mixer aperture <NUM> is fluidly communicatively coupled to a corresponding channel <NUM> of the rotor hub <NUM>. In this manner, the color thixotropic paste <NUM> of a respective cartridge <NUM> flows from the channels <NUM> to the mixer apertures <NUM> and through the mixer apertures <NUM>.

Toward a lower end, the rotor housing <NUM> includes a chamber flange <NUM> that extends circumferentially. The chamber flange <NUM> is sized and shaped to couple to the mixing housing <NUM>. In particular, when the chamber flange <NUM> is coupled to the mixing housing <NUM>, such defines a mixing chamber <NUM>. Each of the mixer apertures <NUM> extends to the mixing chamber <NUM>. The mixing chamber <NUM> is also sized and shaped to receive therein the mixing blades <NUM>. As the color thixotropic paste <NUM> flows into the mixing chamber <NUM> through the mixer apertures <NUM>, the mixing blades <NUM> may be selectively and controllably rotated or spun by being driven by the mixer motor unit <NUM> to provide an appropriate mix ratio of the color thixotropic pastes <NUM> to obtain a desired color output thixotropic paste <NUM>. By way of example and without limitation, an orange color may be produced with a CMYKW value of C:<NUM>, M:<NUM>, Y:<NUM>, K:<NUM>, and W:<NUM>. Again, other colors may be produced by appropriate CMYKW values.

As illustrated in more detail in <FIG>, the mixing housing <NUM> has a generally cone-shaped structure. The mixing housing <NUM> is generally hollow and includes a support member <NUM> that protrudes outwardly. The support member <NUM> is positioned within the cone-shaped structure of the mixing housing <NUM>. The support member <NUM> is sized and shaped to couple thereto a projection module <NUM>. The projection module <NUM> includes a curing light engine assembly <NUM> and a projection module controller <NUM> and associated circuitry in the form of a printed circuit board. The light engine assembly <NUM>, in some embodiments, includes a plurality of radially spaced apart light sources <NUM>. For example, in one embodiment, the light sources <NUM> comprise LED light sources, which emit light at a desired wavelength to cure the forming material, for example, the output thixotropic paste <NUM>. In some embodiments, the wavelength used by the projection module <NUM> may be <NUM>-<NUM> nanometers. Of course, other wavelength light sources ranging, by way of example, from <NUM>-<NUM> nanometers may be used for curing different forming materials, or the desired output thixotropic paste <NUM>.

As previously described, different forming materials are activated by different types of energy. For example, in one embodiment, each light source <NUM> may emit UV or visible light or any other light having an appropriate wavelength based on the properties of forming material, e.g., output thixotropic paste <NUM>, to activate the forming agent. Further, it will be appreciated by one of ordinary skill in the art, upon review of the present disclosure, that when a forming material or agent is used that requires other forms of energy, e.g., infrared light, laser light, X-rays, gamma radiation and the like, the projection module <NUM> may be modified to generate and output such required energy. Therefore, for example, when infrared is projected onto the forming agent, the appropriate hardware and software must be employed so that the projector can generate and project such infrared light. Likewise, if X-rays or gamma radiation is used, the projector may be replaced entirely by an energy emitter that can produce and emit the appropriate energy format onto the forming agent.

In one embodiment, an appropriate wavelength based on the forming material properties produced by the projection module <NUM> and projected onto the forming material is generated by a driver circuit of the projection module controller <NUM>, communicatively coupled to the controller <NUM>, that controls a plurality of Light Emitting Diodes (LED), each diode being of the same UV or visible wavelength, for example, the wavelength may be <NUM>, <NUM> or <NUM> center wavelength. In operation, the driver circuit is modified by software and/or hardware to activate and/or deactivate one or more of the light sources <NUM>, for example, the LED light sources.

The mixing housing <NUM> includes a chamber aperture <NUM> disposed in the support member <NUM> that is substantially coaxial with the central axis <NUM> that extends through the mixing housing <NUM>. The chamber aperture <NUM> includes a portion that generally tapers down proximal to the mixing chamber <NUM>. Thereafter, the chamber aperture <NUM> includes a substantially straight portion that defines an outer periphery of the support member <NUM> in a form of a tip flange <NUM>. The tip flange <NUM> is generally hollow to fluidly communicatively couple to the mixing chamber <NUM>. The tip flange <NUM> is generally flexible and/or is non-transmissive to the curing light. In some embodiments, the tip flange <NUM> may comprise silicone rubber. The tip flange <NUM> is sized and shaped to coupleably receive the mixing tip <NUM>. In this manner, the chamber aperture <NUM> is fluidly and communicatively coupled with the mixing chamber <NUM> such that the mixed and/or blended color thixotropic pastes <NUM> are dispensed or expelled through the mixing tip <NUM>, for example in the form of the output thixotropic paste <NUM>.

The end cap assembly <NUM> is positioned at one end of the 3D printing pen <NUM> proximate to the dispensing apparatus <NUM>. The end cap assembly <NUM>, as shown in more detail in <FIG>, includes a substantially cone-shaped end cap body <NUM> that includes a recess <NUM> disposed therein. The recess <NUM> is sized and shaped to receive therein one or more color sensor(s) <NUM> and optionally a cover plate <NUM>. The one or more color sensor(s) <NUM> are generally configured to detect color or color profile of an object, for example, the color or color profile of the mixed, blended, or distributed color thixotropic pastes <NUM>, in the form of output thixotropic paste <NUM>, dispensed from the mixing tip <NUM>, or another object having the color or color profile desired of the output thixotropic paste <NUM>. More broadly, the one or more color sensor(s) <NUM> can take a wide variety of forms, such as comprise charge coupled devices (CCD), ceramic metal oxide sensors (CMOS), phototransistors, or photodiodes. Furthermore, each of the one or more sensor(s) <NUM> may be an assembly or collection of multiple such devices employing visible filters or neutral density filters at the optical aperture of the sensors. Additionally, this sensor may be a chip type device incorporating multiple such sensors and color filters in a single package. Arrays packaged in this manner may incorporate a means of changing gain settings to modify the luminous flux output characteristics of the device via pin jumper settings. Sensors, sensor arrays, or sensor assemblies are generally capable of communicating with a controller via an analog or digital interface. The one or more color sensor or sensors <NUM> may employ a transimpedance circuit to convert discreet current outputs to voltages and an integrated analog to digital converter circuit to combine the outputs of multiple sensors on a single digital or serial interface.

The one or more color sensors <NUM> are communicatively coupled to an LED ring <NUM> mounted around the end cap body <NUM>. The LED ring <NUM> may include a plurality of light sources in the form of LEDs, with each one illuminating in a certain color. More particularly, the one or more color sensors <NUM> communicate with the LED ring <NUM> to indicate the color sensed which may cause one of the light sources of the LED ring <NUM> that substantially matches the color sensed to illuminate. In this manner, the 3D printing pen <NUM> may communicate to a user by illuminating an appropriate light source of the LED ring <NUM> the color of the dispensed mixed colored thixotropic pastes <NUM>, or output thixotropic paste <NUM>. In some embodiments, the end cap assembly <NUM> may optionally include one or more white light sources, for example, white LED(s). The one or more white LED(s) may be positioned within the LED ring <NUM> to illuminate certain objects and/or samples that may be positioned distant from the 3D printing pen <NUM>. For example, if the object and/or sample is too large to fit within a recess of the sampling area and/or when the white LED near the one or more color sensors <NUM> is insufficient in brightness to properly illuminate the object and/or sample, the one or more white LED(s) may illuminate the object and/or sample with sufficient brightness or clarity.

The 3D printing pen <NUM> also includes a power source <NUM> that supplies or delivers power to one or more components of the 3D printing pen <NUM>. For example, in some embodiments, the power source <NUM> may take the form of a battery compartment <NUM> that is sized and shaped to receive one or more electrical energy storage devices, for example, individual lithium-ion batteries or alkaline batteries that are packaged together to provide electrical power. More generally, such a battery compartment <NUM> includes electrical components that make electrical connection between the one or more individual lithium-ion batteries and primary negative and positive electrical terminals of the battery compartment <NUM>. The negative and positive electrical terminals of the battery compartment <NUM> can be connected to corresponding negative and positive electrical terminals of various components of the 3D printing pen <NUM> to provide electrical power to such components. In some embodiments, the 3D printing pen <NUM> may optionally also include one or more ports. For example, the 3D printing pen <NUM> may include an external device port and a charging port. The external device port can be a USB port, a mini USB port, or another serial or parallel port that allows the 3D printing pen <NUM> to communicate with an external device, such as a personal computer, mobile device, etc. The charging port can allow the 3D printing pen <NUM> to be coupled to an external power source. For example, the external power source can supply electrical power to charge the one or more electrical energy storage devices received in a battery compartment <NUM> of the 3D printing pen <NUM> or, alternatively, directly supply or deliver power to the 3D printing pen <NUM> from the external source.

The controller <NUM> of the 3D printing pen <NUM> is generally operable to control and/or drive one or more operational aspects of the 3D printing pen <NUM>. The controller <NUM> may take a variety of forms which may include one or more integrated circuits, integrated circuit components, digital circuits, digital circuit components, analog circuits, analog circuit components, and various combinations thereof. The controller <NUM> may include a microcontroller, digital signal processor, programmable gate array (PGA) or application specific integrated circuit (ASIC), non-transitory computer- or processor-readable memory such as a read only memory (ROM) and/or random access memory (RAM), and may optionally include one or more gate drive circuits. The controller <NUM> is operably and communicatively coupled to one or more sensors disposed in, on, or around the 3D printing pen <NUM>. For example, the 3D printing pen <NUM> includes a force sensor <NUM> which is coupled to a button <NUM> disposed in the housing <NUM>. In some embodiments, a low-action push button switch may be positioned below the force sensor <NUM> to provide tactile feedback to the user to know whether dispensing is on or off. In some embodiments, as described in more detail below, a force sensing resistor may be provided where a force sensing resistor value is averaged over time to control the overall dispense rate of mixed colored thixotropic paste.

The force sensor <NUM> generally measures the extent of inward force made by a human operator on an interface or body of the button <NUM>, for example, in the form of a force sensing resistor. A signal is produced in response to the measured force, such as digital signal in digital output, and is communicated to the controller <NUM>. The signal alone or in combination with processor executable instructions of the controller <NUM>, for example, correlates the measured force with a dispense rate of the overall mixed colored thixotropic pastes <NUM>, or the output thixotropic paste <NUM>. The controller <NUM>, thereafter, communicates with the one or more stepper motors <NUM> of the motor unit <NUM> to expel or dispense the colored thixotropic paste <NUM> disposed in each cartridge <NUM> at appropriate dispense rate and ratio to match the dispense rate of the overall mixed colored thixotropic pastes <NUM>, e.g., output thixotropic paste <NUM>, and the desired color into the mixing chamber <NUM> and, subsequently, to an environment via the mixing tip <NUM>.

In some embodiments, if no mixing of the colored thixotropic pastes <NUM> is desired, for example, in an instance where only one of the CMYKW colors is desired, the output thixotropic paste <NUM> may include a single colored thixotropic paste <NUM> that may be dispensed through the mixing tip <NUM>. In other instances, where mixing of the colored thixotropic pastes <NUM> is desired to obtain a desired color, the controller <NUM> communicates with the mixer motor unit <NUM> to spin or rotate the mixing blades <NUM>, as described above, to form the mixed colored thixotropic pastes <NUM>, e.g., output thixotropic paste <NUM>, in the desired color. Again, each colored thixotropic paste <NUM> may be dispensed to the mixing chamber <NUM> at an appropriate dispense rate and appropriate ratio to be mixed therein and dispensed through the mixing tip <NUM> at the overall dispense rate based on the force applied to the button <NUM> and measured by the force sensor <NUM>.

As the mixed colored thixotropic pastes <NUM>, e.g., the output thixotropic paste <NUM>, are dispensed through the mixing tip <NUM>, the controller <NUM> communicates with the light engine assembly <NUM> of the projection module <NUM> to transmit a light, invisible or visible, of a certain wavelength. In particular, as described above, the mixed colored thixotropic pastes <NUM>, or an unmixed, singular thixotropic paste <NUM>, include certain resins that include photoinitiators that absorb a certain wavelength of light, which initiates a crosslinking photopolymerization process. The controller <NUM> can selectively send control signals to one or more of the light sources <NUM> of the light engine assembly <NUM> to transmit a light of certain wavelength which cures the resin(s) of the dispensed mixed or unmixed colored thixotropic paste(s) <NUM> until a desired object is formed.

As described above, the 3D printing pen <NUM> includes one or more color sensor(s) <NUM>. The one or more color sensor(s) <NUM> is also communicatively coupled to the controller <NUM>. In some embodiments, the one or more color sensor(s) <NUM> may be used to sense a color that is desired as an output color of the colored thixotropic pastes <NUM>. For example, an operator or user, may position the 3D printing pen <NUM> proximate or adjacent to an object or portion thereof having the desired output color, or the 3D printing pen <NUM> may tap the object or portion thereof having the desired output color. The one or more color sensor(s) <NUM> can sense the desired output color and communicate with the controller <NUM> by sending a control signal indicative of the sensed color. In particular, the controller <NUM> converts a Red, Green, and Blue ("RGB") color model of the sensed color to a CMYKW color model. As described above, the controller <NUM> thereafter may communicate the desired output color to the one or more of the stepper motors <NUM> to dispense the colored thixotropic paste(s) <NUM> as described above when force is applied to the button <NUM>.

As described above, in some embodiments, the one or more color sensor(s) <NUM> may communicate with the LED ring <NUM>, which may cause the LED ring <NUM> to illuminate one of the light sources thereof in a color or color profile that substantially matches the sensed color. In particular, the controller <NUM> is communicatively coupled to the LED ring <NUM>, such that the controller <NUM> sends a control signal to the LED ring <NUM> based on the color sensed by the one or more color sensor(s) <NUM> to illuminate one of the light sources of the LED ring <NUM>. In some embodiments, the 3D printing pen <NUM> may also optionally include a potentiometer and an adjustment mechanism, for example, in a form of a knob. The adjustment mechanism can be configured or operable to select one or more colors of the light sources of the LED ring <NUM>. In particular, the adjustment mechanism can be coupled to the potentiometer, such that the potentiometer detects the position of the adjustment mechanism in relation to selected the light source of the LED ring <NUM> based on the desired output color. The potentiometer is communicatively to the controller <NUM> and sends an output control signal indicative of the selected light source of the LED ring <NUM> based on the desired output color.

In some embodiments, as described above, the knob may function to provide manual color selection, where the knob can be continuously and selectively rotated through an array or plurality of visible colors. In some embodiments, a secondary adjustment mechanism, for example, in the form of a secondary knob may be provided which allows for adjustment of brightness and saturation via a fixed range potentiometer with center detent, in lieu of a continuous potentiometer. The secondary knob can control the addition of a certain color, for example, black (or K) by being moved counter clockwise from the center detent. Conversely, moving the secondary knob in a clockwise direction from the center detent may control the addition of a different color, for example, white (W). As the secondary knob is rotated toward the extreme counter clockwise position, the Cyan, Magenta, and Yellow values may be reduced by the communicably coupled controller <NUM> to zero resulting in pure black color (K). Similarly, as the secondary knob is rotated toward the extreme clockwise position, the Cyan, Magenta, and Yellow values are reduced to zero resulting in pure white (W) color. In some embodiments, a calibration button in the endcap assembly <NUM> may be provided to initiate the color sensing or color selection process.

Thereafter, as described above, the controller <NUM> may communicate the desired output color to the one or more of the stepper motors <NUM> to dispense the colored thixotropic paste(s) <NUM> as described above when force is applied to the button <NUM>.

In some embodiments, the 3D printing pen <NUM> may also optionally include one or more motion sensor(s) <NUM>. The one or more motion sensor(s) <NUM> can take a wide variety of forms, for example, a gyroscope, an accelerometer, a magnetometer, contact switches, and/or another inertial measurement unit (IMU). In particular, the one or more motion sensor(s) <NUM> can sense or capture a position of the 3D printing pen <NUM>. For example, the one or more motion sensor(s) <NUM> can determine whether the mixing tip <NUM> of the 3D printing pen <NUM> is in a substantially upright position, e.g., the mixing tip <NUM> is facing away from a working surface upon which the desired object is to be formed. In such a position, the controller <NUM> communicably coupled to the one or more motion sensor(s) <NUM> may not initiate or activate the 3D printing pen <NUM>. Conversely, if the mixing tip <NUM> is facing the working surface, whether at an angle or orthogonal to the working surface, the one or more motion sensor(s) <NUM> may communicate with the controller <NUM> to activate the 3D printing pen <NUM>.

<FIG> illustrate a 3D printing pen <NUM>, according to one example, non-limiting embodiment. The 3D printing pen <NUM> is generally similar to the 3D printing pen <NUM> illustrated in <FIG>, and as described above, capable of dispensing thixotropic paste(s) of multiple colors simultaneously, dynamically mixing the thixotropic paste(s) of multiple colors at suitable and/or desired ratios, and/or curing the dispensed material to form a desired three-dimensional object, among other things described in more detail below.

The 3D printing pen <NUM> includes a controller <NUM>, a plurality of cartridges <NUM>, a dispensing apparatus <NUM>, a dynamic mixing apparatus <NUM>, and an end cap assembly <NUM>. The 3D printing pen <NUM> includes a housing <NUM> that is sized and shaped to house, either fully or in part, each of the components of the 3D printing pen <NUM>. As illustrated in <FIG>, the housing <NUM> may include one or more individual housing components that are coupled together to form the housing <NUM>. In some embodiments, the one or more individual housing components may be fastened, welded, adhered together, or may be integrally formed as a monolithic housing structure. A lower portion <NUM> of the housing <NUM>, includes a button <NUM>, which is similar to the button <NUM>, and generally operable to dispense an output colored paste, e.g., output colored paste <NUM>. Again, the 3D printing pen <NUM> may include a force sensor which is coupled to the button <NUM> and disposed in the housing <NUM>. Again, as described above, a force sensing resistor or a button switch may be provided.

As described above, the dispensing apparatus <NUM> includes a motor unit <NUM>. The motor unit <NUM>, in some embodiments, may include one or more stepper motors coupled to each cartridge <NUM>. For example, each of the one or more stepper motors may be coupled with a lead screw received in a cartridge body and coupled to a plunger. Thus, as the one or more stepper motor rotates, such rotation drives the lead screw and the plunger to dispense or expel the colored thixotropic paste.

As described above, the dynamic mixing apparatus <NUM> includes a mixing rotor <NUM>, a rotor hub <NUM>, a rotor housing <NUM>, mixing tip <NUM>, and a mixing housing <NUM>. Again, the 3D printing pen <NUM> also includes a mixing motor unit <NUM>, a power source <NUM>, and a projection module <NUM>.

As shown in <FIG>, the end cap assembly <NUM> is positioned at one end of the 3D printing pen <NUM> proximate to the dispensing apparatus <NUM>. The end cap assembly <NUM>, as shown in more detail in <FIG>, includes a substantially cone-shaped end cap body <NUM> that includes a recess <NUM> disposed therein. The recess <NUM> is sized and shaped to receive therein one or more color sensor(s) <NUM> and optionally a cover plate <NUM>. The one or more color sensor(s) <NUM> are generally configured to detect color or color profile of an object, for example, the color or color profile of the mixed, blended, or distributed color thixotropic pastes, in the form of output thixotropic paste, dispensed from the mixing tip <NUM>, or another object having the color or color profile desired of the output thixotropic paste.

An LED ring <NUM> is mounted around the end cap body <NUM>. The LED ring <NUM> may include a plurality of light sources in the form of LEDs, with each one illuminating in a certain color. As described above, the one or more color sensors <NUM> communicate with the LED ring <NUM> to indicate the color sensed which may cause one of the light sources of the LED ring <NUM> that substantially matches the color sensed to illuminate. Again, in some embodiments, the end cap assembly <NUM> may optionally include one or more white light sources, for example, white LED(s). The one or more white LED(s) may be positioned within the LED ring <NUM> to illuminate certain objects and/or samples that may be positioned distant from the 3D printing pen <NUM>. For example, if the object and/or sample is too large to fit within a recess of the sampling area and/or when the white LED near the one or more color sensors <NUM> is insufficient in brightness to properly illuminate the object and/or sample, the one or more white LED(s) may illuminate the sample with sufficient brightness or clarity.

As described above, in some embodiments, the one or more color sensor(s) <NUM> may communicate with the LED ring <NUM>, which may cause the LED ring <NUM> to illuminate one of the light sources thereof in a color or color profile that substantially matches the sensed color. In particular, the controller <NUM> is communicatively coupled to the LED ring <NUM>, such that the controller <NUM> sends a control signal to the LED ring <NUM> based on the color sensed by the one or more color sensor(s) <NUM> to illuminate one of the light sources of the LED ring <NUM>. In some embodiments, the 3D printing pen <NUM> may also optionally include a potentiometer and an adjustment mechanism, for example, in a form of a knob <NUM>. The adjustment mechanism can be configured or operable to select one or more colors of the light sources of the LED ring <NUM>. In particular, the adjustment mechanism can be coupled to the potentiometer, such that the potentiometer detects the position of the adjustment mechanism in relation to selected the light source of the LED ring <NUM> based on the desired output color. The potentiometer is communicatively to the controller <NUM> and sends an output control signal indicative of the selected light source of the LED ring <NUM> based on the desired output color.

In some embodiments, as described above, the knob <NUM> may function to provide manual color selection, where the knob <NUM> can be continuously and selectively rotated through an array or plurality of visible colors. In some embodiments, a secondary adjustment mechanism, for example, in the form of a secondary knob <NUM> may be provided which allows for adjustment of brightness and saturation via a fixed range potentiometer with center detent, in lieu of a continuous potentiometer. The secondary knob <NUM> can control the addition of a certain color, for example, black (or K) by being moved counter clockwise from the center detent. Conversely, moving the secondary knob <NUM> in a clockwise direction from the center detent may control the addition of a different color, for example, white (W). As the secondary knob <NUM> is rotated toward the extreme counter clockwise position, the Cyan, Magenta, and Yellow values may be reduced by the communicably coupled controller <NUM> to zero resulting in pure black color (K). Similarly, as the secondary knob <NUM> is rotated toward the extreme clockwise position, the Cyan, Magenta, and Yellow values are reduced to zero resulting on pure white (W) color. In some embodiments, a calibration button <NUM> in the endcap assembly <NUM> may be provided to initiate the color sensing or color selection process.

<FIG> schematically illustrates a 3D printing system <NUM>, according to one example, non-limiting implementation. In particular, the 3D printing system <NUM> is generally operable to three-dimensionally print an object with one or more embodiments of the 3D printing pen described herein, for example, 3D printing pen <NUM>. <FIG> schematically illustrates various control systems, modules, and other sub-systems that operate to form an object using the 3D printing pen. The 3D printing system <NUM> includes a central control sub-system <NUM> that can be integrated in a 3D printing pen, such as the 3D printing pens <NUM>, <NUM> illustrated in <FIG> and <FIG>, respectively.

The central control sub-system <NUM> includes a controller <NUM>, for example a microprocessor, digital signal processor, programmable gate array (PGA) or application specific integrated circuit (ASIC). The controller <NUM> may be similar to controllers <NUM>, <NUM> illustrated in <FIG>, <FIG>, respectively, that is integrated in the 3D printing pen <NUM>, <NUM>. The central control subsystem <NUM> includes one or more non-transitory storage mediums, for example read only memory (ROM) <NUM>, random access memory (RAM) <NUM>, Flash memory (not shown), or other physical computer- or processor-readable storage media. The non-transitory storage mediums may store instructions and/or data used by the controller <NUM>, for example an operating system (OS) and/or applications. The instructions as executed by the controller <NUM> may execute logic to perform the functionality of the various embodiments of the 3D printing pen described herein, including, but not limited to, logic to establish a pairing relationship with remote accessories, sense occurrence of certain events, actuate various components of a 3D printing pen, e.g., 3D printing pen <NUM>, <NUM>, and any various combinations thereof.

The central control sub-subsystem <NUM> may include one or more sensors <NUM> positioned, configured and operable to sense various operation characteristics of the various elements or components of the 3D printing system <NUM>. For example, the one or more sensors <NUM> can include one or more color sensors, e.g., color sensor(s) <NUM>, <NUM>, force sensor <NUM>, potentiometer, and motion sensor(s) <NUM> that are integrated in the 3D printing pen <NUM>, <NUM>. The one or more sensor(s) <NUM> are communicatively coupled via one or more internal sensor ports to provide signals represented as S<NUM>. SN indicative of such to the controller <NUM>, such as a microprocessor. For example, a color sensor, e.g., color sensor <NUM>, can provide a signal to the controller <NUM> indicative of color detected upon positioning proximal to an object and/or by tapping on an object. The motion sensor, e.g., motion sensor <NUM>, can provide a signal to the controller <NUM> indicative of positioning of the 3D printing pen, e.g., angular or orthogonal positioning of the 3D printing pen relative to a working surface, or certain gestures, such as movement of the 3D printing pen <NUM>, <NUM>, e.g., tapping on an object, etc. For example, the potentiometer can provide a control signal indicative of a positioning of an LED ring indicative of a color of an LED light source.

The central control sub-subsystem <NUM> is communicatively coupled to one or more actuators <NUM> to control one or more operational characteristics of the 3D printing system <NUM>. The controller <NUM>, typically, based on sensed conditions and programmed logic, provides control signals C<NUM>-CN to actuators <NUM> of the 3D printing system <NUM>. The actuators <NUM>, in some implementations, may include a mixing motor, e.g., mixing motor unit <NUM>, dispense motor unit, e.g., motor unit <NUM>, projection module, e.g., projection module <NUM>, and color indicators, e.g., LED ring <NUM>, etc. Although the actuators <NUM> are referenced in <FIG> as including mixing motor <NUM>, motor unit <NUM>, projection module <NUM>, and LED ring <NUM> for clarity of illustration, it is within the scope of the disclosed subject matter that the mixing motor, the motor unit, the projection module, and the LED ring may be anyone of the embodiments described herein, for example, mixing motor unit <NUM>, motor unit <NUM>, projection module <NUM>, LED ring <NUM>, etc..

For example, the controller <NUM> may provide a control signal, e.g., C<NUM>, to the dispense motor unit <NUM> to cause one or more of the colored thixotropic pastes <NUM> to be dispensed through the cartridge <NUM>, <NUM> into the mixing chamber <NUM> upon activation of the force sensor <NUM> providing a certain sensor signal to the controller <NUM>. For example, the controller <NUM> may provide a control signal C<NUM> to the mixing motor unit <NUM> to mix, blend, or distribute the colored thixotropic pastes to obtain a desired color of the output colored paste, e.g., output colored paste <NUM>, upon receiving a sensor signal from the one or more color sensor(s) <NUM> indicative of a certain sensed color. For example, the controller <NUM> may provide a control signal, e.g., C<NUM>, to the projection module <NUM> to initiate or activate the light engine assembly <NUM> to transmit a light, invisible or visible, of a certain wavelength, via one or more of the appropriate light sources <NUM>. For example, the controller <NUM> may provide a control signal, e.g., C<NUM>, to the color indicators, for example, LED ring <NUM>, to illuminate an appropriate light source to indicate the desired output color of the output thixotropic paste, e.g., output thixotropic paste <NUM>.

The central control sub-subsystem <NUM> may include a user interface <NUM>, to allow an end user to operate or otherwise provide input to the 3D printing system <NUM> regarding the operational state or condition of the 3D printing system <NUM>. The user interface <NUM> may include a number of user actuatable controls accessible from the exterior of the 3D printing system <NUM>. For example, the user interface <NUM> may be provided in the 3D printing pen <NUM> and may include a number of switches or keys operable to turn the 3D printing pen <NUM> ON and OFF and/or to set various operating parameters of the 3D printing system <NUM>. The user interface <NUM> may also include one or more visual indicators, for instance light emitting diodes (LEDs). The visual indicators may be single color or may be capable of producing different color indicia corresponding to various operational states or conditions of the 3D printing system <NUM>. For example, upon selection of the desired output color of the output thixotropic paste, the visual indicators may illuminate a number of times to indicate a selection has been made.

Additionally, or alternatively, the user interface <NUM> may include a display, for instance a touch panel display. The touch panel display (e.g., LCD with touch sensitive overlay) may provide both an input and an output interface for the end user. The touch panel display may present a graphical user interface, with various user selectable icons, menus, check boxes, dialog boxes, and other components and elements selectable by the end user to set operational states or conditions of the 3D printing system <NUM>. The user interface <NUM> may also include one or more auditory transducers, for example one or more speakers and/or microphones. Such may allow audible alert notifications or signals to be provided to an end user. Such may additionally, or alternatively, allow an end user to provide audible commands or instructions. The user interface <NUM> may include additional components and/or different components than those illustrated or described, and/or may omit some components. The switches and keys or the graphical user interface may, for example, include toggle switches, a keypad or keyboard, rocker switches, trackball, joystick or thumbstick. The switches and keys or the graphical user interface may, for example, allow an end user to turn ON the 3D printing pen <NUM>, start or end a color sensing mode, communicably couple or decouple to remote accessories, select from a number of colors, activate or deactivate motors or audio subsystems, or activate or deactivate charging, etc..

The central control sub-subsystem <NUM> includes a communications sub-system <NUM> that may include one or more communications modules or components which facilitate communications with various components of one or more external device, such as a personal computer, mobile device, etc. The communications sub-system <NUM> may provide wireless or wired communications to the one or more external devices. The communications sub-system <NUM> may include wireless receivers, wireless transmitters or wireless transceivers to provide wireless signal paths to the various remote components or systems of the one or more paired devices. The communications sub-system <NUM> may, for example, include components enabling short range (e.g., via Bluetooth, near field communication (NFC), or radio frequency identification (RFID) components and protocols) or longer range wireless communications (e.g., over a wireless LAN, Low-Power-Wide-Area Network (LPWAN), satellite, or cellular network), such as for receiving GPS data, and may include one or more modems or one or more Ethernet or other types of communications cards or components for doing so. The communications sub-system <NUM> may include one or more bridges or routers suitable to handle network traffic including switched packet type communications protocols (TCP/IP), Ethernet or other networking protocols. In some implementations, the wired or wireless communications with the external device may provide access to look-up table indicative of various color or color profiles. For example, in lieu of or in addition to determining a desired color via positioning of the 3D printing pen <NUM>, <NUM> or selecting a color from the LED ring <NUM>, an end user may select a color from a variety of colors displayed in the user interface <NUM>, which may be stored in a look-up table or the like in the external device.

The central control sub-system <NUM> includes a power interface manager <NUM> that manages supply of power from a power source <NUM>, e.g., power source <NUM>, <NUM> to the various components of the central control sub-system <NUM>, for example, the central control sub-system <NUM> integrated in the 3D printing pen <NUM>, <NUM>. The power interface manager <NUM> is coupled to the controller <NUM> and the power source <NUM>. Alternatively, in some implementations, the power interface manager <NUM> can be integrated in the controller <NUM>. The power source <NUM> may include external power supply or electrical energy storage devices that are received in the battery compartment <NUM> of the 3D printing pen <NUM>. The power interface manager <NUM> may include power converters, rectifiers, buses, gates, circuitry, etc. In particular, the power interface manager <NUM> can control, limit, restrict the supply of power from the power source <NUM> based on the various operational states of the 3D printing system <NUM>.

In some embodiments or implementations, the instructions and/or data stored on the non-transitory storage mediums that may be used by the controller, such as, for example, ROM <NUM>, RAM <NUM> and Flash memory (not shown), includes or provides an application program interface ("API") that provides programmatic access to one or more functions of the central control sub-system <NUM>. For example, such an API may provide a programmatic interface to control one or more operational characteristics of the 3D printing system <NUM>, including, but not limited to, one or more functions of the sensor(s) <NUM>, actuator controller(s) <NUM>, and user interface <NUM>. Such control may be invoked by one of the other programs, actuators <NUM>, other remote device or system (not shown), or some other module. In this manner, the API may facilitate the development of third-party software, such as various different user interfaces and control systems for other devices, plug-ins, and adapters, and the like to facilitate interactivity and customization of the operation and devices within the 3D printing system <NUM>.

In an example embodiment or implementation, components or modules of the central control sub-system <NUM> and other devices within the 3D printing system <NUM> are implemented using standard programming techniques. For example, the logic to perform the functionality of the various embodiments or implementations described herein may be implemented as a "native" executable running on the controller, e.g., microprocessor <NUM>, along with one or more static or dynamic libraries. In other embodiments, various functions of the central control sub-system <NUM> may be implemented as instructions processed by a virtual machine that executes as one or more programs whose instructions are stored on ROM <NUM> and/or random RAM <NUM>. In general, a range of programming languages known in the art may be employed for implementing such example embodiments, including representative implementations of various programming language paradigms, including but not limited to, object-oriented (e.g., Java, C++, C#, Visual Basic. NET, Smalltalk, and the like), functional (e.g., ML, Lisp, Scheme, and the like), procedural (e.g., C, Pascal, Ada, Modula, and the like), scripting (e.g., Perl, Ruby, Python, JavaScript, VBScript, and the like), or declarative (e.g., SQL, Prolog, and the like).

In a software or firmware implementation, instructions stored in a memory configure, when executed, one or more processors of the central control sub-system <NUM>, such as microprocessor <NUM>, to perform the functions of the central control sub-system <NUM>. The instructions cause the microprocessor <NUM> or some other processor, such as an I/O controller/processor, to process and act on information received from one or more sensor(s) <NUM> to provide the functionality and operations of the 3D printing system <NUM> described herein.

The embodiments or implementations described above may also use well-known or other synchronous or asynchronous client-server computing techniques. However, the various components may be implemented using more monolithic programming techniques as well, for example, as an executable running on a single microprocessor, or alternatively decomposed using a variety of structuring techniques known in the art, including but not limited to, multiprogramming, multithreading, client-server, or peer-to-peer (e.g., Bluetooth®, NFC or RFID wireless technology, mesh networks, etc., providing a communication channel between the devices within the 3D printing system <NUM>), running on one or more computer systems each having one or more central processing units (CPUs) or other processors. Some embodiments may execute concurrently and asynchronously, and communicate using message passing techniques. Also, other functions could be implemented and/or performed by each component/module, and in different orders, and by different components/modules, yet still achieve the functions of the central control sub-system <NUM>.

In addition, programming interfaces to the data stored on and functionality provided by the central control sub-system <NUM>, can be available by standard mechanisms such as through C, C++, C#, and Java APIs; libraries for accessing files, databases, or other data repositories; scripting languages; or Web servers, FTP servers, or other types of servers providing access to stored data. The data stored and utilized by the central control sub-system <NUM> and overall 3D printing system may be implemented as one or more database systems, file systems, or any other technique for storing such information, or any combination of the above, including implementations using distributed computing techniques.

Different configurations and locations of programs and data are contemplated for use with techniques described herein. A variety of distributed computing techniques are appropriate for implementing the components of the illustrated embodiments in a distributed manner including but not limited to TCP/IP sockets, RPC, RMI, HTTP, and Web Services (XML-RPC, JAX-RPC, SOAP, and the like). Other variations are possible. Other functionality could also be provided by each component/module, or existing functionality could be distributed amongst the components/modules within the 3D printing system <NUM> in different ways, yet still achieve the functions of the central control sub-system <NUM> and 3D printing system <NUM>.

Furthermore, in some embodiments, some or all of the components of the central control sub-system <NUM> and components of other devices within the 3D printing system may be implemented or provided in other manners, such as at least partially in firmware and/or hardware, including, but not limited to, one or more application-specific integrated circuits ("ASICs"), standard integrated circuits, controllers (e.g., by executing appropriate instructions, and including microcontrollers and/or embedded controllers), field-programmable gate arrays ("FPGAs"), complex programmable logic devices ("CPLDs"), and the like. Some or all of the system components and/or data structures may also be stored as contents (e.g., as executable or other machine-readable software instructions or structured data) on a computer-readable medium (e.g., as a hard disk; a memory; a computer network, cellular wireless network or other data transmission medium; or a portable media article to be read by an appropriate drive or via an appropriate connection, such as a DVD or flash memory device) so as to enable or configure the computer-readable medium and/or one or more associated computing systems or devices to execute or otherwise use, or provide the contents to perform, at least some of the described techniques.

<FIG> is a flow diagram illustrating a high-level method <NUM>, according to one example, non-limiting implementation. The method <NUM> generally illustrates various operational and/or functional characteristics of a 3D printing system, e.g., 3D printing system <NUM>, having a 3D printing pen, e.g., 3D printing pen <NUM>, <NUM>. At <NUM>, optionally, a position of the 3D printing pen is determined. For example, one or more motion sensor(s), e.g., one or more motion sensor(s) <NUM>, communicatively indicate to a controller, e.g., controller <NUM>, <NUM>, <NUM>, whether a tip of the 3D printing pen is positioned at an angle or orthogonal to a working surface. If the 3D printing pen is positioned at an angle or orthogonal to a working surface, the 3D printing pen may be in an operational state.

At <NUM>, a desired output color of an output thixotropic paste, e.g., output thixotropic paste <NUM>, is determined. In one implementation, the desired output color of the output thixotropic paste may be determined at 230a via the controller receiving signal(s) from one or more color sensor(s), e.g., one or more color sensor(s) <NUM>, <NUM> indicative of a color sensed by positioning the 3D printing pen proximate to an object having the desired output color or by tapping on the object or portion thereof with the desired output color.

In another implementation, the desired output color of the output thixotropic paste may be determined at 230b via the controller receiving signal(s) from one or more potentiometer(s) indicative of a positioning of an adjustment mechanism, for example, in a form of a knob, as described above. Again, the adjustment mechanism may be configured or operable to select one or more colors of light sources, for example, light sources of an LED ring, e.g., LED ring <NUM>, <NUM>.

In another implementation, at 230c, the desired output color of the output thixotropic paste may be selected from a selection of potential colors available on a user interface of the 3D printing pen, e.g., user interface <NUM>. Again, as described above, the 3D printing pen may be communicatively coupled to an external device having a look-up table stored therein with the selection of output colors. Further, it is also within the scope of the disclosed subject matter, that in some implementations, the method may include each one of, or any combination, of the steps described above.

At <NUM>, optionally, the 3D printing pen, may illuminate a light source indicative of the selected output color. For example, as described above, a 3D printing pen may include an LED ring, e.g., LED ring <NUM>, <NUM>, wherein one of the light sources of the LED ring may be illuminated, one time or any number of times, to indicate to the end user that a certain output color has been selected.

At <NUM>, the controller of the 3D printing pen, based on the desired output color of the output colored thixotropic paste, converts an RGB color model into a CMYKW color model.

At <NUM>, the controller of the 3D printing pen, may receive signal(s) indicative of an output dispense rate from one or more force sensor(s), e.g., force sensor(s) <NUM>. For example, as described above, based on pressing of a button, e.g., button <NUM>, the force sensor(s) can detect an applied force to determine a desired overall dispense rate.

At <NUM>, the controller of the 3D printing pen, sends signal(s) indicative of the overall dispense rate to a motor unit, e.g., motor unit <NUM>, <NUM>, to activate or actuate motors, e.g., stepper motors <NUM>, of the 3D printing pen. As described above, the motor unit <NUM>, <NUM>, when actuated, dispenses individual colored thixotropic paste <NUM> disposed in a corresponding cartridge, e.g., cartridge <NUM>, <NUM>, through a nozzle, e.g., nozzle <NUM>, into a mixing chamber, e.g., mixing chamber <NUM>. As described above, based on the overall dispense rate, the controller communicates with the motor unit <NUM>, <NUM> to dispense appropriate ratios and dispense rate of individual colored thixotropic pastes to substantially match the desired overall dispense rate and the desired output color.

At <NUM>, the controller of the 3D printing pen sends signal(s) to a mixer motor unit, e.g., mixer motor unit <NUM>, <NUM>, to mix, blend, and/or distribute individual colored thixotropic pastes <NUM> received in the mixing chamber. Again, under some conditions or operational states, the controller may or may not send signal(s) to the mixer motor unit if no mixing or blending is required. For example, if the selected output color is only one of cyan, magenta, yellow, black, etc., then the mixer motor unit <NUM>, <NUM> is not operated or actuated.

At <NUM>, upon the output colored thixotropic paste being dispensed from a mixing tip, for example, mixing tip <NUM>, <NUM>, the controller of the 3D printing pen or 3D printing system, may send signal(s) to a projection module, e.g., projection module <NUM>, <NUM> to emit a light having a certain desired wavelength. For example, as described above, a light engine assembly of the projection module, may include one or more light sources that may emit light at a desired wavelength to cure the forming material, for example, the output thixotropic paste.

While not illustrated in detail, in some embodiments, the 3D printing pen may include storage chambers that may be selectively dispensed or discarded upon one or more uses. For example, in some embodiments, any excess colored thixotropic pastes <NUM>, individually, or mixed or combined to form the output thixotropic paste may be stored in one or more storage chamber(s), or discarded or expelled. Moreover, the various embodiments or implementations described above can be combined to provide further embodiments, as long as they fall within the scope of the claims.

Claim 1:
A three-dimensional printing pen (<NUM>), comprising:
a plurality of cartridges (<NUM>), each cartridge (<NUM>) having a hollow cartridge body (<NUM>) including a colored thixotropic paste (<NUM>), a color of each thixotropic paste (<NUM>) being different from a color of another thixotropic paste (<NUM>);
a plurality of nozzles (<NUM>), each nozzle (<NUM>) fluidly communicatively coupled to a corresponding cartridge (<NUM>);
a motor unit (<NUM>) operably coupled to the plurality of cartridges (<NUM>), the motor unit (<NUM>) operable to expel the colored thixotropic paste (<NUM>) from each cartridge (<NUM>) through the corresponding nozzle (<NUM>);
a mixing tip (<NUM>) fluidly communicatively coupled to the plurality of nozzles (<NUM>), the mixing tip (<NUM>) sized and shaped to dispense therethrough one or more of the colored thixotropic pastes (<NUM>) in a form of an output thixotropic paste (<NUM>);
a projection module (<NUM>) having a light engine assembly (<NUM>) that emits light having a wavelength, the light being projected to the output thixotropic paste (<NUM>) to cure the output thixotropic paste (<NUM>) that is dispensed from the mixing tip (<NUM>); and
a housing (<NUM>) at least partially housing each of the plurality of cartridges (<NUM>), the plurality of nozzles (<NUM>), the motor unit (<NUM>), the mixing tip (<NUM>), and the projection module (<NUM>).