Patent Application
20150125230
Embodiments relate to machines and apparatuses that have a spindle arm to which machine tools are interchangeably attached. More specifically, embodiments relate to milling machines that include spindle arms that are controlled to move between a first position at which a work-piece is milled or inspected and a second position at which tools are interchanged on the spindle.
Milling machines are used to quickly remove metal from blanks or work-pieces. Typically, the milling machines include a spindle, on which tools are mounted for cutting, machining or otherwise forming the work-piece into a component. The tools are operatively connected to rotating elements of the spindle so the tool, which has cutting teeth or edges, is rotated for removing material from the work-piece and forming the component by rotating the tool on the spindle.
A tool storage device, known as a magazine, has multiple cutting tools for performing multiple different milling or machining operations. Each cutting tool typically has a tapered holder that mates with a receiving end of the spindle to secure the tool to the end of the spindle. The spindle is controlled to move between positions at which a tool is used to function and remove material from the work-piece and positions at which the tool is removed from the spindle and another tool is secured to the spindle. This automated tool interchange significantly increases the flexibility and efficiency of the milling machine.
In recent years, due to miniaturization of electrical and sensor components, it has become possible to build compact accurate sensor devices that can be attached to the tool holders of milling machines. These devices require power, and some require a significant amount of power; however, transmitting a larger amount of power to these devices is a challenge, because it requires the inclusion of a sizeable battery or battery pack. Relatively large batteries almost always pose weight challenges. Another method of feeding power to these devices is to use an external power cable; however, power cables limit the usability of the tools since the cable (sometimes called an “umbilical cord”) prevents automatic tool changes and hinders automatic machining operations. More specifically, the cable will be “ripped” out of the device, if it is not first disconnected. To that end, connecting and disconnecting the power cable adds processing steps to the milling operations increasing the amount of time necessary to machine a component.
Embodiments relate to an apparatus that comprises a spindle that is configured to receive and support different tools. The spindle is moveable between one or more first positions for forming or inspecting a work-piece and one or more second positions at which tools are interchanged on and off the spindle. The apparatus also comprises a tool having a tool holder that is detachably secured to an end of the spindle for the interchange of tools on and off the spindle. The tool also has a work-piece end distal to the tool holder. An energy harvesting device is provided on the tool and is in electrical communication with the work-piece end and the energy harvesting device is configured to harvest a form of energy generated from the operation of the apparatus to generate sufficient electrical power for wholly powering the work-piece end.
The work-piece end may comprise a sensor for inspecting features of the work-piece that have been formed and/or a laser marking tool and/or tools that perform automated steps in the manufacture of the work-piece into a component. Non-limiting examples of such tools may include a dowel pin inserter, rivet installer, automatic threaded inserter or a puncher. In non-limiting examples, power may be harvested from compressed air injected through the spindle, a coolant fluid injected through the spindle or rotation of components of the spindle. Embodiments resolve the above-described power supply problem by using the power sources available at the spindle, to locally generate significant power. At the same time, the tool can be automatically interchanged, maintaining flexibility and efficiency.
A more particular description briefly stated above will be rendered by reference to specific embodiments thereof that are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments and are not therefore to be considered to be limiting of its scope, the embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:
Embodiments are described herein with reference to the attached figures wherein like reference numerals are used throughout the figures to designate similar or equivalent elements. The figures are not drawn to scale and they are provided merely to illustrate aspects disclosed herein. Several disclosed aspects are described below with reference to non-limiting example applications for illustration. It should be understood that numerous specific details, relationships, and methods are set forth to provide a full understanding of the embodiments disclosed herein. One having ordinary skill in the relevant art, however, will readily recognize that the disclosed embodiments can be practiced without one or more of the specific details or with other methods. In other instances, well-known structures or operations are not shown in detail to avoid obscuring aspects disclosed herein. The embodiments are not limited by the illustrated ordering of acts or events, as some acts may occur in different orders and/or concurrently with other acts or events. Furthermore, not all illustrated acts or events are required to implement a methodology in accordance with the embodiments.
With respect to
As shown, the tool 14 has a work-piece end 22 that faces the work-piece 18 and is distal to the tool holder 16. In this illustrative embodiment, the work-piece end 22 comprises a sensor 24 that may be used to inspect to the work-piece 18 as part of a machining process. In a non-limiting example, the sensor 24 may be an imaging device or visual metrology sensor. Accordingly, the sensor 24 may include a camera 25 and lens 26 and a lighting element 28 (including a plurality of LEDs) mounted to a housing 30. The camera 25 may include discreet output lines that can be programmed to create different lighting patterns, depending in part on the feature of the work-piece 18 being inspected.
The tool holder 16 is mounted on a housing 30 opposite the sensor 24. More specifically, the tool holder 16 has a mounting flange 32 for attachment of the tool holder 16 to the housing 30. As shown in
The sensor 24 is in electrical communication with a wireless transceiver 37 via a communication line 35 such as an Ethernet cable, and the sensor 24 transmits signals indicative a condition being monitored by the sensor 24. In the non-limiting example of an imaging device, the sensor 24 sends data representing images of features of the work-piece 18 formed during manufacturing. The transceiver 37 transmits the data to a computer 46 that also includes a transceiver 48 for wireless communication between the sensor 24 and computer 46.
The computer 46 may include software programming with executable instructions to perform one or more inspection routines and/or tasks. More specifically, the software programming may be configured to determine if the tool 14 and sensor 22 are in position to perform an inspection routine and/or task. Once the tool 14 is determined to be in position, the computer 46 transmits signals to the transceiver 37 to activate the sensor 14 to generate work-piece inspection data such as images of features of the work-piece 18 according to a predetermined inspection routine. To that end, the computer 46 communicates with the control system 20 for transmission of signals indicative of the status of the inspection routine and/or tasks. Accordingly, the computer 46 transmits a signal to the control system 20 indicating an inspection routine and/or task has been completed. The control system 20 is equipped with programmed executable instructions according to a predetermined machining operation to form a component from the work-piece 18. The machining operation includes work-piece inspection routines and/or tasks, so the control system 20 is configured to control the operation of the spindle 12 to interchange a cutting tool (not shown) with the tool 14 for inspection of the work-piece 18. The control system 20 also generates signals to the computer 46 indicating the tool 14 is in position for inspection.
An energy harvesting device 34 is mounted within the housing 30 and generates power from operating conditions associated with the operation of the apparatus 10 and/or spindle 12. In a non-limiting example, the harvesting device 34 may harvest energy from fluid flow through the spindle and tool holder 16. As shown in
In an embodiment, the energy harvesting device 34 may comprises a turbine generator 40 in fluid flow communication with the first and second fluid flow passages 38, 42. The turbine generator 40 is supported in the housing 30 by support members 31. Accordingly, when fluid is delivered to the tool, the turbine generator 40 generates power or electricity that is delivered to the sensor 24. The turbine generator 40 may also be in electrical communication with the transceiver 37 and lighting element 28 (including any control circuits that control the lighting) to power all components of the tool 14.
During prototype testing a 150W Tesla turbine was used to power a programmable National Instruments 1776C camera and lens and a Blue Tooth transceiver (Phoenix Contact PN 2693091). Such a turbine generator operating at 14,000 rpm can produce about 10V of power. It was determined that with the delivery of about 7 to 8 cubic feet per minute of compressed air the turbine generator has an electrical output of 60 watts, which was enough to power the camera and the transceiver. By the time compressed air reaches the spindle nose 47 the air is under pressure at about 60 psi; however, a coolant may be delivered to the spindle nose 47 at 1000 psi providing capacity to generate more power. In such an embodiment the tool 14 may need to be configured to exhaust some coolant so as not to overload the turbine generator 40. To that end, the turbine generator 40 may include a power bleed off circuit including a resistor circuit to bleed off power on occasions the turbine generator 40 produces too much power.
With respect to the embodiments illustrated in
As shown, a generator 58 is mounted to the housing 52. The generator 58 is operatively connected to the rotating shaft 50 via a belt and pulley mechanism 60. Thus, when the shaft 50 rotates the generator 58 outputs power or electricity via electrical lines 62 to a work-piece end including a sensor or tool as described above. In the embodiment shown in
In the embodiment shown in
The above-described embodiment including an apparatus and/or tool with an energy harvesting device to power the tool to perform routines or steps of a component forming operation solves the above-describe problems associated with prior art devices. While the embodiments described relative
While embodiments have been described with reference to various embodiments, it will be understood by those skilled in the art that various changes, omissions and/or additions may be made and equivalents may be substituted for elements thereof without departing from the spirit and scope of the embodiments. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the embodiments without departing from the scope thereof. Therefore, it is intended that the embodiments not be limited to the particular embodiment disclosed as the best mode contemplated, but that all embodiments falling within the scope of the appended claims are considered. Moreover, unless specifically stated, any use of the terms first, second, etc., does not denote any order or importance, but rather the terms first, second, etc., are used to distinguish one element from another.
