Patent Application
20230356323
The present invention relates to Computational Numerical Control (CNC) machining tools for marking of workpieces, and more specifically a battery-powered CNC laser marker with a built-in motion sensor.
CNC tools are used for milling or drilling, so there is no need for active control by the CNC machine. Thus, CNC tools are generally passive, apart from certain exceptions (i.e. active tools), including the alignment tool. The alignment tool is used to find reference points on a workpiece, and so needs to wirelessly communicate with the CNC machine. To address this need, an external transmitter is connected to a digital output on the CNC machine. The external transmitter relays the signal to the active tool using some form of wireless communication (e.g., infrared (IR) technology, Bluetooth®, WiFi, etc.). Because both systems (the CNC machine and the active tool) are generally “closed” (i.e. no hardware or software interface available), active tools are manufactured in conformity with the technical requirements of specific CNC machines and cannot easily be deployed on other CNC machines from other manufacturers or older models without incurring expenses and/or inconvenience.
Thus, battery-powered laser marker having a built-in motion sensor for use in a CNC machine are desired for improving laser marking of CNC machined parts, particularly as compared to utilizing standard passive CNC tools.
Aspects of the present invention are directed to laser machining systems and manufacturing apparatuses or methods. More particularly, the present invention relates to a CNC machine with a battery-powered laser marker having a built-in motion sensor.
In accordance with one aspect of the present invention, a laser marking tool for use with a CNC machine is disclosed. The laser marking tool comprises a housing; a laser disposed within the housing; at least one sensor disposed within the housing and adapted to interpret a predetermined motion of the CNC machine as a command for the tool to perform a respective predetermined function; and a power source coupled to the laser.
The invention is best understood from the following detailed description when read in connection with the accompanying drawings, with like elements having the same reference numerals. When a plurality of similar elements are present, a single reference numeral may be assigned to the plurality of similar elements with a small letter designation referring to specific elements. When referring to the elements collectively or to a non-specific one or more of the elements, the small letter designation may be dropped. This emphasizes that according to common practice, the various features of the drawings are not drawn to scale unless otherwise indicated. On the contrary, the dimensions of the various features may be expanded or reduced for clarity. Included in the drawings are the following figures:
Aspects of the invention are described herein with reference to a laser marking tool for use in a CNC machine. However, it will be understood by one of ordinary skill in the art that the exemplary tools described herein are not limited to a laser marking tool for use with a CNC machine, but may be applicable to other known CNC tools or similar devices.
The terms “workpiece” and “parts” (e.g. machined parts) as described herein and throughout the specification may encompass a variety of components formed (by a CNC machine) from a block of raw material, including but not limited to steel, aluminum, Inconel, titanium, Chrome-Molybdenum-Vanadium (CMV). Non-limiting examples of machined parts include a turbine, motor shaft, splines, etc. Likewise, the term “information” as described herein and throughout the specification may encompass a variety of data which may be useful for traceability of machined parts or required for a serialization process. However, laser marking is not limited to functional purposes (e.g. a QR code for providing date of manufacture, material bath, machinist, engineer, etc.), and may be additionally or optionally used for aesthetic marking, including but not limited to, artistic designs such as logos, text, images, layout patterns, etc. Still further, the term “marking” encompasses 2D cutouts, which could be used to make 3D structures, used as templates, or other applications. It should also be understood that laser marking is not limited to certain industries, which may include high value, high security industries such as aerospace and healthcare.
Referring now to
Thus, CNC tool 200 can operate with various CNC machines, without the need for customization or integration, via a one-way communication from the CNC machine 300 to a CNC tool 200 attached to the CNC machine 300. The communication is characterized as “one-way” in that in operation, an active (compared to passive) CNC tool 200 requires input(s) from the CNC machine 300, such as start or stop signals from a controller of the CNC machine 300, for example, but the tool 200 does not necessarily communicate back any information to the CNC machine 300. Further, the “one-way” communication is performed wirelessly, because a wired connection to a CNC tool 200 is less practical due to movement of the CNC machine 300, components thereof, or other machines downstream/upstream the CNC machine 300. Still further, the communication may comprise standard G-codes, i.e. the industry programming language for CNC machines 300, or other suitable programming languages.
Turning now to
In an exemplary embodiment, as illustrated in
The CNC tool changer carousel 308 may comprise a tool changer which include a series of tool holders 302 disposed relative to each other at predetermined intervals along a circumference of tool changer carousel 308. Thus, as the tool changer rotates in response to a command from a controller of the CNC machine 300, having wired connections is undesirable, particularly when the individual tool holders (and thus the CNC tools 200) are configured to spin or rotate at high speeds.
Importantly, the CNC tool 200 may have a laser 204 powered by a power source 210, such as a battery, which is preferable over a wired or corded laser since this wired or corded option would require modifications to at least the CNC tool changer carousel 308 and spindle 310. In an exemplary embodiment, the laser diode 204 may comprise a semiconductor laser. For example, the semiconductor laser is a continuous wave laser diode 204 having a wavelength of 390-470 nm and a power output of 1 W-5 W. Exemplary multi-watt blue semiconductor lasers 204 may include Metal Can® PLPT9 450LB_E Blue Laser Diode In TO90 Package, as designed by Osram Opto Semiconductors GmbH of Regensburg, Germany. Additionally, or optionally, the laser 204 may comprise a Q-switched, diode-pumped solid-state (DPSS) laser. In one non-limiting example, the DPSS laser has the following characteristics: a wavelength of 1064 nm, a pulse energy (or power output) in a range between 10-5000 mW, a pulse duration in a range between 0.1-100 ns, and a pulse repetition rate in a range between 0.1-100 kHz. Additionally, or optionally, the marking tool 200 includes one or more of a diode cap and a diode heat sink 220 for dissipating heat generated by the laser 204.
In an exemplary embodiment, the battery-operated laser 204 is sufficiently powerful to mark or engrave metals to form high resolution functional and/or aesthetic patterns. Further, the battery 210 is of sufficient energy and power capacity and density, such that the battery-operated laser 204 may be housed in a small enough package so it can be installed in a standard CNC tool holder 302 for laser marking. In an exemplary embodiment, battery 210 comprises a Li-ion battery cell having approximately 10 Whr capacity, such as Panasonic 18650 Li-ion 3180 mAh battery, as designed by Panasonic Energy Co. Ltd. of Japan.
To facilitate further multiple use cycles of the CNC tool 200, the battery 210 may be removable, such as for facilitating battery replacement. Additionally, or optionally, the battery 210 is rechargeable, and the CNC tool 200 comprises a charging port 1250 (
As best shown in
Referring now to
As shown in
As shown in
As discussed above, a synchronization signal is required for operation of the CNC tool 200 based on motion of the CNC machine 300 or parts thereof. Thus, CNC tool 200 includes at least one sensor 206 configured to detect performance of a predetermined motion (rotation, translation, etc.) of the spindle 310. Then, the at least one sensor 206 is adapted to interpret this predetermined motion of the CNC machine 300 as a command for the CNC tool 200 to perform the respective predetermined function. A non-exhaustive list of commands (interpreted by at least one sensor 206) and corresponding motions for a CNC tool 200 is provided in Table 1 below.
The user can stop the marking between lines for inspection or other reasons, then the marking will restart at the right point once the next C2 command (Table 1) is sent.
The operation sequence described above is an exemplary process or method comprising steps that are performed sequentially in the order recited. However, it should be understood from the description herein that one or more steps may be omitted and/or performed out of the described sequence of the process while still achieving the desired result. Further, additional steps may be included within the operation sequence.
For vector marking, or for alignment reasons, the user may want to switch ON the laser 204 continuously using command C3 (Table 1). Then, the CNC stage can move following a contoured pattern. At the end of marking, the laser can be switched OFF using command C1 (Table 1). Because the beam may not be concentric to the spindle axis, a Z translation should be used to avoid a circular error in the resulting marking when using a rotational command. When moving from one feature to another features and across areas that must not be marked, the user can choose between the two operation modes described in
A second embodiment of a CNC tool 200 for use in a CNC machine 300 according to the present invention is discussed below. The components of this embodiment, generally correspond to the first embodiment described above, with reference to
Finally, regarding safety features with respect to the embodiments discussed above, the CNC tool 200 is configured to be activated only when properly attached to the CNC machine 300, such that a user may not manually activate the laser 204. This will reduce or prevent the inherent risks correlated to any improper use of lasers 204. To achieve this, the laser 204 of the present disclosure can be triggered or activated (i.e., turned ON) only when the at least one sensor 206 detects the type of motions that may not be easily replicated manually. In a non-limiting example, translational movements/accelerations, which may result from mere handling of the CNC tool 200 or from mechanical shocks, are disregarded by the at least one sensor 206. Additionally, or optionally, the accelerometer 206 can be used to wake up the electronic circuitry or microcontroller of CNC tool 200, if the CNC tool 200 is in sleep mode or to initiate the interrupt service routine, but the gyroscope 206 can be read to perform a confirmatory function of measuring the rotational speed, in order to properly identify the command. A non-exhaustive list of properly interpreted commands are listed in Table 2 below.
Referring to
Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention.
This application claims priority from U.S. Provisional Application Ser. No. 63/338,488, titled “Battery Powered CNC Laser Marker With Built-In Motion Sensor,” filed May 5, 2022, incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63338488 | May 2022 | US |
