Abstract:
Analytical instrument inductors are provided that can include bundled wired conductive material about a substrate. Analytical instrument inductors are also provided that can include: a tubular substrate defining a plurality of flanges extending outwardly from a core of the substrate wherein opposing flanges define portions of the core; at least one pair of wires wound about a first portion of the core and between at least two flanges, the pair of wires extending to and wound about a second portion of the core; and wherein the one pair of wires are operatively coupled to an analytical instrument to provide inductance. Methods for preparing an instrument inductor are provided. The methods can include bundling wires about and within multiple exterior openings of a hollow-cored substrate; and connecting each of the bundles across the openings.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to U.S. Provisional Patent Application Ser. No. 61/991,835 which was filed on May 12, 2014, the entirety of which is incorporated by reference herein. 
     
    
     STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT 
       [0002]    This invention was made with Government support under Contract No. HSHQDC-09-00057 awarded by the U.S. Department of Homeland Security, Science and Technology Directorate, Explosives Division. The Government has certain rights in the invention. 
     
    
     TECHNICAL FIELD 
       [0003]    The present disclosure relates generally to analytical instrumentation and in particular embodiments, to analytical instrumentation that relies on electronics. Particular aspects of the disclosure relate to analytical instrument inductors and methods for producing same. 
       BACKGROUND 
       [0004]    Analytical instrumentation such as mass spectrometry instrumentation often utilize an inductor such as an RF inductor that includes a resonant circuit for producing signals required for the analytical instrumentation. In particular example uses, RF signals can be required by many mass spectrometers, and for generating wave forms, for example. There is a need in the art for smaller designs of analytical instrumentation to make them hand held and more portable. The present disclosure provides a novel inductor design that can be utilized within analytical instrumentation and in particular embodiments, mass spectrometry instrumentation. 
       SUMMARY OF DISCLOSURE 
       [0005]    Analytical instrument inductors are provided that can include bundled wired conductive material about a substrate. The substrate can define a plurality of openings about a hollow core, with each of the openings confining a plurality of the bundled wires and each bundle being connected with a wire across the openings. 
         [0006]    Analytical instrument inductors are provided that can include: a tubular substrate defining a plurality of flanges extending outwardly from a core of the substrate wherein opposing flanges define portions of the core; at least one pair of wires wound about a first portion of the core and between at least two flanges, the pair of wires extending to and wound about a second portion of the core; and wherein the one pair of wires are operatively coupled to an analytical instrument to provide inductance. 
         [0007]    Methods for preparing an instrument inductor are provided. The methods can include bundling wires about and within multiple exterior openings of a hollow-cored substrate; and connecting each of the bundles across the openings. 
     
    
     
       DRAWINGS 
         [0008]    Embodiments of the disclosure are described below with reference to the following accompanying drawings. 
           [0009]      FIG. 1  is a schematic of an instrument according to an embodiment of the disclosure. 
           [0010]      FIG. 2  is a circuit diagram of an RF subsystem according to an embodiment of the disclosure. 
           [0011]      FIG. 3  is a depiction of a substrate of a coil according to an embodiment of the disclosure. 
           [0012]      FIG. 4  is another depiction of a substrate and coiled members about same according to an embodiment of the disclosure. 
           [0013]      FIG. 5  is another depiction of a substrate having coils there about according to an embodiment of the disclosure. 
           [0014]      FIG. 6  is a depiction of a coil preparation method at one stage according to an embodiment of the disclosure. 
           [0015]      FIG. 7  is a depiction of a coil preparation method at another stage according to an embodiment of the disclosure. 
           [0016]      FIG. 8  is a depiction of a coil preparation method at still another stage according to an embodiment of the disclosure. 
           [0017]      FIGS. 9-30  are depictions of a coil at progressive stages of preparation according to an embodiment of the disclosure. 
           [0018]      FIG. 31  is performance data utilizing coils of the present disclosure. 
           [0019]      FIG. 32  is additional performance data utilizing coils of the present disclosure. 
           [0020]      FIG. 33  is additional performance data utilizing coils of the present disclosure. 
           [0021]      FIG. 34  is additional performance data utilizing coils of the present disclosure. 
       
    
    
     DESCRIPTION 
       [0022]    This disclosure is submitted in furtherance of the constitutional purposes of the U.S. Patent Laws “to promote the progress of science and useful arts” (Article 1, Section 8). 
         [0023]    The present disclosure will be described with reference to  FIGS. 1-34 . Referring first to  FIG. 1 , an example instrument  10  is shown by schematic diagram. Example instrument  10  can be configured as a mass spectrometer, and this mass spectrometer may include several components. Example components can include sample preparation ionization component  14 , mass analyzer component  16 , which include a mass separator, as well as a detector component  18 . These three components  14 ,  16 , and  18  can be coupled to a processing and control unit. Instruments such as these are described in U.S. Pat. No. 7,582,867 issued Sep. 1, 2009, the entirety of which is incorporated by reference herein. 
         [0024]    Unique to this instrument is the inclusion of an inductor that can be utilized to generate RF signals that can be utilized to dictate the mass separation parameters. Other instruments that can utilize this inductor can include but are not limited to nuclear magnetic resonance and/or low frequency instruments such as those using less than 1.6 mHz. 
         [0025]    Referring to  FIG. 2 , an example circuit is shown that includes an RF amplifier, feedback, and tank circuit. Within a tank circuit can be a coil as shown, and this coil has in the past been configured as a solenoid inductor or coil. Typical designs have utilized air-core inductors in the past to prevent magnetic saturation. 
         [0026]    Referring next to  FIG. 3 , a substrate that can be utilized for the inductor of the present disclosure is shown. Substrate  30  is depicted as one cross section of a circular or tubular designed substrate for the mounting of metallic coils thereon. The mounting of metallic coils can include the bundling of wires about the substrate. The wires can be in pairs and may include multiple pairs of wires. 
         [0027]    Substrate  30  can include a central cylinder  32  that may have one or more of a plurality of flanges  34  extending therefrom. Within that set of flanges  34  can be restraining flanges  36  on the outermost portion, as well as interior flanges  38 . As can be seen, restraining flanges  36  may have a width or depth that is significantly larger than interior flanges  38 . The combination of the cylinder and flanges can define the openings  37  of the substrate about the hollow core of the central cylinder  32 . As can be seen, the substrate can be substantially tubular, but the substrate can be insulative as well. 
         [0028]    The flanges can define portions of the core  43 , for example. At least one pair of wires can be wound about a first portion of the core and between at least two flanges. The pair of wires can extend to and be wound about a second portion of the core. The first and second portions of the core may be defined by at least three flanges. 
         [0029]    The inductor can include another pair of wires wound about a third portion of the core and between at least two flanges. One of the two flanges defining the third portion of the core can be one of the two flanges defining the first portion of the core. The other pair of wires can extend to and about a fourth portion of the core. In accordance with example implementations, an even number of portions of the core are defined by the flanges. The substrate can further define two sections with each section including half of the portions of the core. 
         [0030]    In accordance with example implementations, flanges can extend approximately 0.3 inches from the exterior of the central tubular construct  32 . The entire width in one cross section extending from flange edge to opposing flange edge can be approximately 1 inch, and the entire length of the cylindrical substrate can be approximately 1.6 inches. In accordance with example implementations, one set of flanges  34  can be aligned to be about 0.5 inches from either end of the entire construct, thus taking up approximately 0.6 inches. Each individual flange can be approximately 0.025 inches in depth, and the spacing between the flanges can be approximately 0.055 inches in width. In accordance with example implementations, the larger edge construct flange  36  can be approximately 0.080 inches in width. In accordance with example implementations, the depth or outer perimeter of the central tubular construct  32  can be approximately 0.375 inches wide, with an opening of about 0.228 inches. 
         [0031]    Referring next to  FIG. 4 , construct  40  is shown in accordance with one cross section with bundled wires  42  therein. In this cross section, multiple bundling of wires can reside in each of opposing openings defined between flanges  44 . As can be seen, each of the wires bundled within each individual opening or slot can be connected via a single cross over wire to the slot adjacent thereto, and then additional bundles provided in the slot adjacent thereto. Accordingly bundles of wires using windings can be gradually built, and the resulting construct can have first turns removed from the second as far as possible, the distance of removal being dictated by the construct. 
         [0032]    Referring next to  FIG. 5 , another example of a construct  50  (the conductor was Type 2 Litz, 34 AWG 26/48, Red Single Polyurethane, 0.002″ PFA Jacket to 0.012″ +0.002″/−0.004″) is shown that demonstrates the relationship of flange construct  52  to the wires  54  bundled therein. As noted in this construct, certain dimensions are provided, and these dimensions are as follows: 
         [0000]    
       
         
               
               
               
             
               
               
               
             
           
               
                   
               
               
                 Parameter (inch) 
                 Value 
                 Description 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 OD (in) 
                 1.000 
                 Outside diameter of conductors 
               
               
                 ID (in) 
                 0.400 
                 Inside diameter of conductors 
               
               
                 w (in) 
                 0.055 
               
               
                 s 
                 6 
                 Number of slots 
               
               
                 p (in) 
                 0.080 
                 Pitch of slots 
               
               
                 Pf (turns per in{circumflex over ( )}2) 
                 3455 
                 Packing factor (experimentally 
               
               
                   
                   
                 determined) 
               
               
                   
               
             
          
         
       
     
         [0033]    Referring next to  FIG. 6 , a processing step for preparing the coil according to an embodiment of the disclosure is provided. In accordance with this embodiment of the disclosure, a  6 -slot coil for a four-winding inductor (bifilar with center-taps) can be prepared. Shims shown can be utilized on opposing recesses about the recess having wire wound therein. The shims may prevent the winding from collapsing the flanges of the recess during winding, for example. As can be seen in  FIG. 6 , a coil can be mounted to a stationary fixture, and the coil rotated about an axis to draw wires within slots of the coil. Construct  60  can have a slot  62  extending there through. Slot  62  can be utilized to allow for the crossover of a single wire between different spaces within construct  62  to allow for the single wire crossover between bundles. 
         [0034]    Referring next to  FIG. 7 , in another stage of processing, another construct  66  is shown. As shown, construct  66  includes a tubular member  70  that can be utilized to provide for the transfer of coils from stock to construct  66 . 
         [0035]    Referring next to  FIG. 8 , construct  68  is shown in its completed form. In accordance with example implementations and according to other stages of processing,  FIGS. 9 through 30  demonstrate a single construct at different stages of processing. As can be seen, a first pair of wires is wound about the portions of one section of the substrate and then a second pair of wires is wound about the other section of the substrate. To aid in the preparation of the inductor, shims are placed in openings, between flanges, and/or over portions to facilitate the bundling of wires in specific portions. 
         [0036]    Processing begins with the substrate of the coil in  FIG. 9 . In  FIG. 10 , bifilar windings are started as shown with the start end of wire passing from the bottom of slot to the left and secured to the shaft. 
         [0037]    Referring next to  FIG. 11 , shims can be added to all empty slots to prevent plastic walls from bowing out when winding. The orientation of the shim slots can be opposite of that of the axial cut through the slot walls.  FIG. 12  depicts winding the first slot a predefined number of turns while being cautious not to let the windings snag on the shims. In  FIGS. 13 and 14 , selected shims can be removed for inspection of next step then windings can be routed from top of first slot to bottom of second slot. This occurs along the axial cut through the walls of the slots. 
         [0038]    Referring to  FIGS. 15 and 16  shims can be returned to the substrate to prevent bowing slots while winding and then in  FIGS. 17 and 18 , the shims can be removed to complete the winding of one side of construct. Referring to  FIGS. 19-21 , the windings can be completed then terminated by passing them through the holes of the side wall then pulled through snug. 
         [0039]    Referring next to  FIGS. 22-30 , the opposite half of the construct can be prepared winding from the center out as above. Upon completing the windings tubing can be placed over the two pairs of center-tap conductors of the coil—one for each phase pair. 
         [0040]    Referring next to  FIGS. 31-34 , the inductive coil of the present disclosure was characterized as having the following performance. In  FIG. 31  the Q-factor of the coil was measured as a function of the iron powder core position relative to the number of turns they were inserted from the flush face of the coil form. Similarly, the resonance frequency, inductance and calculated system capacitance is shown as a function of core position in  FIGS. 34 ,  35  and  36 , respectively. 
         [0041]    In compliance with the statute, embodiments of the invention have been described in language more or less specific as to structural and methodical features. It is to be understood, however, that the entire invention is not limited to the specific features and/or embodiments shown and/or described, since the disclosed embodiments comprise forms of putting the invention into effect.