Abstract:
An apparatus comprises a housing and a tool holder that is mounted to a first end of the housing. The tool holder is configured for selectively engagement with a spindle to support the tool and selective disengagement from the spindle for interchanging the tool with other tools. The tool further comprises a work-piece end mounted to a second end of the housing to perform component forming functions and/or component inspection functions. At least one energy harvesting device at the housing is configured to harvest a form of energy associated with the operation of the apparatus to generate sufficient electrical power for wholly powering the machine implement. Accordingly, there is an electrical interconnection between the at least one energy harvesting device and the work-piece end.

Description:
BACKGROUND 
       [0001]    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. 
         [0002]    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. 
         [0003]    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. 
         [0004]    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. 
       SUMMARY 
       [0005]    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. 
         [0006]    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. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    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: 
           [0008]      FIG. 1  illustrates a side view of an apparatus with a tool mounted on a spindle in accordance with embodiments. 
           [0009]      FIG. 2  illustrates the components of the tool and a sectional view of the spindle. 
           [0010]      FIG. 3  illustrates an exploded view of the tool shown in  FIG. 1 . 
           [0011]      FIG. 4  illustrates a schematic representation of an embodiment with an energy harvesting device that harvests rotational movement of the spindle. 
           [0012]      FIG. 5  illustrates a schematic representation of the embodiment of  FIG. 4  wherein the energy harvesting device powers a laser marking tool. 
           [0013]      FIG. 6  illustrates a schematic representation of the embodiment of  FIG. 4  wherein the energy harvesting device powers a tool for the automated insertion of threaded inserts. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    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. 
         [0015]    With respect to  FIGS. 1 and 2 , an embodiment is shown and is an apparatus  10  comprising a spindle  12  and a tool  14  including a tool holder  16  secured in mating relationship with an end of the spindle  12 . In a non-limiting example, the spindle  12  may be a component of a milling machine for cutting and machining, or performing other fabricating steps, to form a component from a work-piece  18 . Accordingly, the spindle  12  may be operatively linked to mechanical drive systems and control systems  20  to move the spindle  12 , including rotating elements of the spindle  12 , to machine a work-piece  18  with cutting tools or to move the spindle  12  to interchange tools on and off the spindle  12 . The above-described operation of a machining tool with a spindle  12  is well known to those skilled in the art. 
         [0016]    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. 
         [0017]    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  FIGS. 1-3 , tool holder  16  may have a generally conical shape that is positioned in mating relationship with the spindle nose  32 . The attachment and detachment of the tool holder  16  relative to the spindle  12  is a routine operation that is well known to those skilled in the art. 
         [0018]    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 . 
         [0019]    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. 
         [0020]    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  FIG. 3 , the spindle  12  has a hollow shaft  36  forming a first fluid flow passage  38  through the spindle  12  to the spindle nose  47  to which a tool is attached. During milling or cutting operations, compressed air is injected through the fluid flow passage  38  to the spindle nose  47 . Tool holders for cutting tools such as drill bits typically have fluid flow passages through the tool holder and bit so that air is delivered through the nose of the tool to clear the work-piece  18  of material removed by the tool. In addition, coolant fluid may also be delivered through the spindle  12  and cutting tool to control and maintain the operating temperatures of the tool and work-piece  18  during milling or cutting operations. Accordingly, a second fluid flow passage  42  extends through the tool holder  16  for delivery of fluid flow to the energy harvesting device  34 . 
         [0021]    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 . 
         [0022]    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. 
         [0023]    With respect to the embodiments illustrated in  FIGS. 4-6 , the energy harvesting device  34 ′ harvests energy from the rotational motion of the spindle  12  transmitted to a shaft  50  of the tool  14 ′ and tool holder  16 ′. As shown, the tool includes a housing  52  with a stop  55  for attachment to a stationary part of the spindle  12  (not shown). Bearings  54  are disposed between the shaft  50  and the housing  52  so that the housing  52  remains stationary as the tool holder  16 ′ and shaft  50  rotate. Similar configuration, including a stationary housing and stop feature, may be found on milling tools that include right angle heads that are well known to those skilled in the art. 
         [0024]    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  FIG. 5 , the work-piece end  18 ′ includes a laser marker  64  and a transceiver  66 . The electrical lines  62  deliver electricity to the laser marker  64  to power the device and mark a work-piece or component as desired. As described above, the transceiver  66  may receive signals from the computer  46  or control system  20  wherein the signals may indicate steps in a marking routine or procedure. In addition, in a non-limiting example the transceiver  66  and/or one or more control circuits of the laser marker  64  may transmit signals indicative of the status of a laser marking step and/or the position of the laser marker  64 . 
         [0025]    In the embodiment shown in  FIG. 6 , the work-piece end  18 ′ includes device  68  for inserting threaded inserts  70  into a work-piece or a component. The device  68  may include a probe  72  on which a threaded insert  70  is positioned for insertion into a component or work-piece. The probe  72  and device  68  are configured and operatively connected to the shaft  50  so that the probe  72  rotates and moves toward and away from a work-piece for rotating insertion of the threaded insert. As shown, the device  68  may include a holder  74  for supporting multiple threaded inserts  70  to perform a plurality of operations during machining or component forming operations. Accordingly, the device  68  is equipped with moving parts and control circuitry to move a threaded insert  70  from the holder  74  to the probe  72 . As further shown, the tool  14 ′ includes a transceiver  66  that receives signals from the computer  46  or control system  20  to perform steps for inserting the threaded inserts, and transmits signals indicative of the status of each step. 
         [0026]    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  FIGS. 1-6  include a sensor  24 , laser marker  64  and inserter device  68 , the embodiment is not so limited and covers other tools such as dowel inserters, rivet installers and punchers. In addition, embodiments are not limited to the particular energy harvesting devices described herein. In a non-limiting example, the generator  58  in  FIGS. 4-6  may take the form of magnets mounted to the shaft  50  and electrical coils mounted to an internal surface of the housing  52 , whereby the rotation of the shaft  50  and magnets generates electricity that is transmitted to the work-piece end of the tool  14 ′. In addition, other operating conditions such as temperature (heat) or vibration may be harvested wherein the energy harvesting device may include a thermoelectric harvesting device, a thermo-voltaic harvesting device, a piezoelectric harvesting device or combination of these devices. 
         [0027]    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.