Abstract:
A method and systems for disengagement of a chain and sprocket actuation system is provided. In one version, an actuation system mechanically couples a motor with a rotatable feature. The rotatable feature may be a threaded stem that alternately raises and lowers a gate as the feature is rotated in a respective direction. A removable key comprised within the actuation key. When the key is removed from engagement with the motor, that rotatable feature is decoupled from the motor. A manual fixture, such as a wheel, may be used to rotate the rotatable feature by hand. The rotatable feature may thus be driven by the motor, or alternately decoupled from the motor and driven by hand.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to mechanical entrainment method san systems. The present invention more particularly relates to methods and systems to alternately and selectively couple with, and decouple from, a source of mechanical force and a movable object. 
       BACKGROUND OF THE INVENTION 
       [0002]    The prior art includes methods and systems that couple sources of mechanical force with rotatable objects, such as shafts. Yet in the course of the use of many mechanical systems, a first source of mechanical force may fail, or a second source may be preferred over the first source. For example, a motor that is coupled with a threaded stem may fail to perform due to lack of fuel. Where the motor is coupled with the threaded stem, or other rotatable object, by an actuation system, alternate rotation of the object or threaded stem by means other than the motor may be impeded by that actuation system. 
         [0003]    There is a long-felt need to provide methods and systems that selectively enable an engagement of an object with a first source of mechanical force and alternately allows the first source to be selectively decoupled. 
       OBJECTS OF THE INVENTION 
       [0004]    It is a principal object of the present invention to provide an actuation system that allows selective decoupling of the system from source mechanical force and an object. 
         [0005]    Another object of the invention is to provide a reliable system for the purpose described herein. 
       SUMMARY OF THE INVENTION 
       [0006]    This and other objects of the present invention are made obvious in light of this disclosure, wherein a method and system for selectively engaging a movable object with at least two alternate sources of mechanical force are provided. 
         [0007]    According to a first aspect of the method of the present invention, an actuation assembly includes a removable coupling key, wherein the actuation assembly transfers mechanical force form a mechanical force source, such as a motor, to a moveable object, such as a rotatable force. When the removable coupling key is disengaged from the remainder of the actuation assembly, the mechanical force source is decoupled from the moveable object, and mechanical force is no longer transferred from the mechanical force source to the moveable object. The removable key may then be reengaged to again enable the actuation system, wherein the mechanical force source is again mechanically coupled with the moveable object 
         [0008]    According to a second aspect of the method of the present invention, a system provides selective connectivity between a drive shaft of a motor with a threaded stem, such as a lead screw. The removable coupling key is disposed between the drive shaft and a first sprocket. A link chain receives and transfers rotational force from the first sprocket to the threaded stem. A second sprocket, may be entrained to the threaded stem and be disposed between the link chain and the threaded stem, whereby mechanical force is translated from the drive shaft through the removable key, the first sprocket, the link chain, and to the threaded stem. A threaded nut may be attached to or coupled with the second sprocket, wherein the threaded nut is limited in linear motion that is orthogonal to the direction of rotation of the second sprocket and the resultant rotation of the threaded stem. Turning the second sprocket as driven by the link chain causes the threaded nut to rotate the threaded stem. Removing the coupling key disengages and decouples the motor drive shaft from the first sprocket, and thereby reduces inhibition of manual rotation of the threaded stem by the actuation system. 
         [0009]    According to a third aspect of the method of the present invention, the motor drive shaft may provide mechanical force that is transferred through the removable key to a first pulley, from the first pulley to a cable, from the cable to a second pulley, and from the second pulley to a rotatable object. 
         [0010]    According to a fourth aspect of the method of the present invention, the threaded nut coupled with the second sprocket or second pulley may be rotatably coupled with, or restrained by, a fixture, such as a plate, to maintain the threaded nut in position relative to the sprocket and yet allow free rotation of the threaded nut to drive the threaded stem. 
         [0011]    According to a fifth aspect of the method of the present invention, the actuation system may further comprise a manual fixture that enables manual rotation of the threaded stem, preferably when the removable coupling key is disengages from the remainder of the actuation system. The manual fixture may be a wheel or one or more handles. 
         [0012]    According to a fifth aspect of the method of the present invention, the actuation system may be or comprise a gate that is movable for the purpose of alternately impeding and allowing a fluid to flow, such as water in an irrigation channel. The threaded stem may be coupled to the gate. 
         [0013]    According to a fifth aspect of the method of the present invention, a drive sprocket and a driven sprocket of an actuation system are mounted on a threaded gate stem. The driven sprocket is coupled to both the threaded gate stem and to a chain. The chain is additionally coupled to a drive sprocket, wherein the drive sprocket is alternately driven in a clockwise direction and a counterclockwise direction by a motor. The gate stem rises through a threaded drive-nut. The threaded drive-nut is mounted into the driven sprocket and is further captured by a retaining plate or collar. The retaining plate and/or collar causes the gate stem to rise or descend in correspondence as the driven sprocket turns alternately clockwise and counterclockwise. The drive sprocket may be mounted on the drive motor and be machined to accept a removable locking key, or “drive key”. When the drive key is in place, the drive key accepts rotational force of a drive shaft of the motor, whereupon the drive key transfers the rotational force to the drive sprocket. The drive sprocket thereupon turns the chain, and the chain engages with and turns the driven sprocket. When removed the drive key is removed from engagement with the drive shaft and the drive sprocket, the drive shaft spins freely and allowing a manual operation of the driven sprocket. A hand-wheel may be used to manually turn the threaded gate stem. Electrical fusing of the motor provides over-torque protection of the motor. 
       INCORPORATION BY REFERENCE 
       [0014]    All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited. All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference in their entirety and for all purposes to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. 
         [0015]    Such incorporations include U.S. Pat. No. 7,255,128 (inventors: Sandhu, et al.; issued on Aug. 14, 2007) titled “System and method for detecting flow in a mass flow controller”; U.S. Pat. No. 5,967,697 (inventors: Larsen, et al.; issued on Oct. 19, 1999), titled “Flood control gate safety device”; U.S. Pat. No. 4,877,352 (inventors: Tuttle, et al.; issued on Oct. 31, 1989) titled “Method and apparatus for control of an upstream water level”; U.S. Pat. No. 3,952,522 (inventor Shettel, R.; issued on Apr. 27, 1976) titled “Irrigation systems automation”; U.S. Pat. No. 3,354,655 (inventor: Armond, Charles V.; issued on Nov. 28, 1967), titled “Automatically operated door for water control”; U.S. Pat. No. 2,979,909 (inventor: Stanley, Broadbent; issued on Apr. 18, 1961), titled “Sluice Gate”; U.S. Pat. No. 2,361,439 (inventor: Samuel, Weiss; issued on Oct. 31, 1944), titled Torque control switch; and U.S. Pat. No. 2,041,576 (inventor: Alfred, Suksdorf; issued on May 19, 1936), titled “Control system”. 
         [0016]    The publications discussed or mentioned herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention. Furthermore, the dates of publication provided herein may differ from the actual publication dates which may need to be independently confirmed. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0017]    These, and further features of various aspects of the present invention, may be better understood with reference to the accompanying specification, wherein: 
           [0018]      FIG. 1  is a side view of a first actuation system in a first operational state, whereby a threaded stem is entrained with a motor-driven drive shaft; 
           [0019]      FIG. 2  is a top view of the first actuation system of  FIG. 1  in the first operational state; 
           [0020]      FIG. 3  is a top view of the first actuation system of  FIG. 1  and  FIG. 2  in a second operational state, whereby the threaded stem is decoupled with the motor-driven drive shaft by removal of a drive key from engagement with the drive shaft; 
           [0021]      FIG. 4  is a side view of a second actuation system in a first operational state, the second actuation including comprising a drive pulley mechanically coupled by a belt with a driven pulley, whereby the threaded stem is entrained with the motor-driven drive shaft; 
           [0022]      FIG. 5  is a top view of the second actuation system of  FIG. 4  in the first operational state; 
           [0023]      FIG. 6  is a side view of an alternate configuration of the first actuation system of  FIGS. 1 ,  2  and  3  further comprising a plate to which the threaded nut and first sprocket are both rotatably coupled; 
           [0024]      FIG. 7  is a side view of a still alternate configuration of the first actuation system of  FIGS. 1 ,  2 ,  3  and  6  further comprising a flow control gate that is coupled with a bottom end of the threaded stem; 
           [0025]      FIG. 8  is a side view of a yet alternate configuration of the first actuation system of  FIGS. 1 ,  2 ,  3 ,  6  and  7  further comprising a hand wheel that is coupled with the threaded nut; 
           [0026]      FIG. 9  is a partial, detailed cut-way side-view of an alternate version system of the first actuation system of  FIGS. 1 ,  2 ,  3 ,  6  and  7 ; 
           [0027]      FIG. 10  is a top view of the alternate version system of the first actuation system  FIG. 9 ; and 
           [0028]      FIG. 11  is a top view of the alternate version system of the first actuation system  FIG. 9  and  FIG. 10 . 
       
    
    
     DETAILED DESCRIPTION 
       [0029]    It is to be understood that this invention is not limited to particular aspects of the present invention described, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims. 
         [0030]    In the following detailed description of the invention, reference is made to the accompanying drawings which form a part hereof, and in which is shown, by way of illustration, specific embodiments in which the invention may be practiced. In the drawings, like numerals describe substantially similar components throughout the several views. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments may be utilized and structural, logical, and electrical changes may be made without departing from the scope of the present invention. 
         [0031]    Methods recited herein may be carried out in any order of the recited events which is logically possible, as well as the recited order of events. 
         [0032]    Where a range of values is provided herein, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range, is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges and are also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits ranges excluding either or both of those included limits are also included in the invention. 
         [0033]    Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, the methods and materials are now described. 
         [0034]    It must be noted that as used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural referents unless the context clearly dictates otherwise. It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as “solely,” “only” and the like in connection with the recitation of claim elements, or use of a “negative” limitation. 
         [0035]    Referring now generally to the Figures and particularly to  FIG. 1 ,  FIG. 1  is a side view of a first actuation system  100 . The first actuation system  100  includes a drive key  102  that is removably disposed between a drive shaft  104  of a motor  106  and a drive sprocket  108 . The motor  106  may be an alternating current motor or a direct current motor in alternate preferred embodiments of the present invention. 
         [0036]    When engaged for entrainment within the first actuation system  100 , the drive key  102  is placed within a centered drive sprocket aperture  108 A of the drive sprocket  108  and transfers rotational force from the drive shaft  104  to the drive sprocket  108  via the link chain  110 . The drive sprocket  108  engages the link chain  110  to entrain a second, driven sprocket  112 . The driven sprocket  112  is rotated by the link chain  110  as the drive sprocket  108  receives and transfers mechanical force originating from the drive shaft  104 . The driven sprocket  112  is additionally coupled with a captured threaded nut  114 , whereby the driven sprocket  112  rotates the captured threaded nut  114  about a Y-axis when, and as, the link chain  110  rotates the driven sprocket  112 . 
         [0037]    The threaded nut  114  is captured in relation to the link chain  110  and the driven sprocket  112  within an X-Z axis. When the threaded nut  114  is turned clockwise or counter-clockwise about the Y-axis, the threaded nut  114  engages with a threaded stem  116  to alternately move the threaded stem  116  up and down along the Y-axis. More specifically, a mechanical engagement of an inner threaded channel  118  of the threaded nut  114  with the threaded stem  116  causes the threaded stem  116  to travel along the Y-axis as the threaded nut  114  is alternately rotated clockwise or counter clockwise about the Y-axis. 
         [0038]    Referring now generally to the Figures and particularly to  FIG. 2 ,  FIG. 2  is a top view of the first actuation system  100 . The drive sprocket  108  and the driven sprocket  112  are preferably co-planar and aligned within an operating plane defined by an X-axis and a Z-axis, wherein the Y-axis of  FIG. 1 , the Z-axis of  FIG. 2 , and the X axis of  FIG. 1  and  FIG. 2  are all three mutually orthogonal. The drive key  102  is depicted in both  FIG. 1  and  FIG. 2  in a first state operational state wherein the drive key  102  is disposed between the drive shaft  104  of the motor  106  and the drive sprocket  108 . The drive key  102  is positioned when in the first operational state of the first actuation system  100  to transfer rotational force in either a clockwise direction, or alternately in a counter clockwise direction, from the drive shaft  104  and to the drive sprocket  108 . 
         [0039]    Referring now generally to the Figures and particularly to  FIG. 3 ,  FIG. 3  is a top view of the first actuation system  100 , wherein the drive key  102  has been placed into a second operational state by removal of the drive key  102  by a user from engagement with either the drive shaft  104  or the drive sprocket  108 . A central drive sprocket aperture  108 A of the drive sprocket  108  is shaped to receive and retain the drive key  102 . An outer edge  102 A of the drive key  102  is sized and shaped to fit within the drive sprocket aperture  108 A to engage with the drive sprocket  108  when the drive key  102  is placed in the first operational state. A key aperture  1028  of the drive key  102  is shaped and sized to receive the drive shaft  104  and to enable a transfer of rotational force from the drive shaft  104  when the drive key  102  is positioned in the first operational state and within the drive sprocket aperture  108 A. 
         [0040]    As shown in  FIG. 3 , when the drive key  102  is placed into the second operational state wherein the drive key  102  is removed from engagement or contact with the drive sprocket aperture  108 A, the drive shaft  104  does not engage with the drive sprocket  108  through the drive key  102  or other means, and the first actuation system  100  therefore does not entrain the threaded stem  116  with the drive shaft  104 . The threaded stem  116  is thus available to receive rotational force from an alternative force that the motor  106 , and without inhibition by any resistive force generated by, or delivered from, the motor  106 , when the first actuation system  100  is placed into the second operational state by removal of the drive key  102  from contact with the drive sprocket  108 . 
         [0041]    Referring now generally to the Figures and particularly to  FIG. 4 ,  FIG. 4  is a side view of a second actuation system  400 . The second actuation system  400  includes the drive key  102  that is illustrated in  FIG. 4  to be removably disposed between the drive shaft  104  and a drive pulley  402 . When engaged for entrainment within the second actuation system  400 , the drive key  102  is placed within a central pulley aperture  402 A of the drive pulley and transfers rotational force from the drive shaft  104  to the drive pulley  402 . The drive pulley  402  further engages a cable  404  to entrain a second, driven pulley  406 . It is understood that the cable  404  may be a belt. 
         [0042]    The driven pulley  406  is rotated by the cable  404  as the drive pulley  402  receives and transfers mechanical force originating from the drive shaft  104 . The driven pulley  206  is additionally coupled with the captured threaded nut  114 , whereby the driven pulley  406  rotates the captured threaded nut  114  about the Y-axis when, and as, mechanical force received from the cable  404  rotates the driven pulley  406 . The threaded nut  114  is captured In relation to the cable  404  and driven pulley  406  and, when turned, forces the threaded stem  116  to alternately up and down along the Y-axis. 
         [0043]    Referring now generally to the Figures and particularly to  FIG. 5 ,  FIG. 5  is a top view of the second actuation system  400 . The drive pulley  402  and the driven pulley  406  are preferably co-planar and are each aligned within the operating plane defined by the X-axis and the Z-axis. The drive key  102  is depicted in both  FIG. 4  and  FIG. 4  in a first operational state of the second actuation system  400 , wherein the drive key  102  is disposed between the drive shaft  104  of the motor  106  and the drive pulley  402 . The drive key  102  is positioned when in the first operational state of the second actuation system  400  to transfer rotational force in either a clockwise direction, or alternately in a counter clockwise direction, from the drive shaft  104  and to the drive pulley  402 . 
         [0044]    The second actuation system  400  may be placed into the second operational state by removal of the drive key  102  by the user from engagement or contact with the drive pulley aperture  402 A, wherein the drive shaft  104  does not engage with the drive pulley  402  through the drive key  102  or other means, and the second actuation system  400  therefore does not entrain the threaded stem  116  with the drive shaft  104 . The threaded stem  116  is thus available to receive rotational force from an alternative force other than the motor  106 , and without inhibition by any resistive force generated by, or delivered from, the motor  106  when the second actuation system  400  is placed into the second operational state by removal of the drive key  102  from contact with the drive pulley. 
         [0045]    Referring now generally to the Figures and particularly to  FIG. 6 ,  FIG. 6  is a side view of an alternate configuration of the first actuation system  100  further comprising a first plate  600  to which the threaded nut  114  and driven sprocket  112  are rotatably coupled, and a top plate  602  having a top plate aperture  602 A through which both the stem  116  and the threaded nut  114  extend. The first plate  600  and the top plate  602  captures and maintains the threaded nut  114  substantively within the X-Z plane while allowing the threaded nut  114  to be rotated, whereby the engagement of the inner threaded channel  114 A of the threaded nut with the threaded stem  116  causes the threaded stem  116  to travel along the Y-axis as the threaded nut  114  is alternately rotated clockwise or counter clockwise about the Y-axis. A 
         [0046]    Referring now generally to the Figures and particularly to  FIG. 7 ,  FIG. 7  is a side view of a still alternate configuration of the first actuation system  100  further comprising a flow control gate  700  that is coupled with a bottom end of the threaded stem  116 . As the driven sprocket  112  alternately is rotated the clockwise and counter clockwise the threaded stem  116  alternately raises and lowers the control gate  116  along the Y-axis, whereby fluid (not shown), such as irrigation water, is alternately released and contained. 
         [0047]    Referring now generally to the Figures and particularly to  FIG. 8 ,  FIG. 8  is a side view of a yet alternate configuration of the first actuation system  100  further comprising a hand wheel  800  removably coupled with the threaded nut  114 . A hand wheel aperture  800 A is sized and shaped to extend about the stem  116  and engage with the threaded nut  114  sufficiently to enable transfer of manual force applied by the user to the hand wheel  800  to the threaded nut  114  and therefrom to the threaded stem  116 , whereby the user may manually position the threaded stem  116  alternately up and down the Y-axis. 
         [0048]    More particularly, the user may turn the hand wheel  800  by manually applying force to cause the threaded nut  114  to alternately rotate clockwise or counter-clockwise about the Y-axis. This rotation of the threaded nut alternately causes the threaded stem  116  to travel in one of the two directions of the Y-axis. This movement of the threaded stem  116  causes the gate  700  that is coupled to the threaded stem  116  to move up or down along the Y-axis in entrainment with the threaded stem  116 . 
         [0049]    Referring now generally to the Figures and particularly to  FIG. 9 ,  FIG. 9  is a partial, detailed cut-way side-view of an alternate version system  900  of the first actuation system  100 . A box assembly  902  partially encloses the seventy tooth driven sprocket  112 . A fixed tubular sprocket-bushing riser  903  extends from a bottom box plate  902 A of the box assembly  902  and into a driven sprocket aperture  112 A. A Waterman/Fresno drive nut  904  is press-fit into the driven sprocket  112 , and presents an inner threaded channel  904 A that engages with the threaded stem  116 . The driven sprocket  112  is constrained from moving along the Y-axis by containment between a top cover  902 B of the box assembly  902  and the sprocket-bushing riser  903 . The drive nut  904  may be pressed into a machine-out pocket of the driven sprocket  112 , wherein the pocket is under-sized I comparison with the drive nut  904  and the driven sprocket is heated above 500 degrees Fahrenheit to accept the seating into, and press fit coupling of, the drive nut  904  with the driven sprocket  112 . 
         [0050]    The box assembly  902  is coupled to a motor housing  906  that encloses the motor  106 . An adjustable motor mount  908  positions and maintains the motor  105  in relation to the twenty three tooth drive sprocket  108 . A hingeable cover  910  may be opened or closed to expose the motor  106 , the drive sprocket  108 , drive key  102 , the number forty link chain  110  (not shown) and other elements for removal, replacement or adjustment. 
         [0051]    Referring now to the drive sprocket  108 , the drive sprocket is captured between a UMHW washer  913  and a motor drive block  914  of the drive shaft  104 . The UMHW washer  912  is disposed between a motor top plate  106 A of the motor  106  and the drive sprocket  108 . The motor drive block  914  has a larger cross-sectional area in the X-Z plane than a lower channel  1088  of the drive sprocket aperture  108 A through which a drive shaft stem  1088  fully extends. 
         [0052]    An upper channel  108 C of the drive sprocket aperture  108 A is sized to permit the drive sprocket  108  to fully rotate about the motor drive block  914  without substantive inhibition by the motor drive block  914  when the drive key  102  is removed from the upper channel  108 C, as when the first actuation system  100  is placed into the second operational state by removal and decoupling of the drive key  102 . Alternatively, the drive key  102  is sized and shaped to fit into the upper channel  108 C of the drive sprocket  108 A and to thereby place the alternate system  900  into the first operational state, wherein the drive key  102  is disposed between the driven sprocket  108  and the motor drive block  914  and the drive sprocket  108  is thereby entrained with the drive shaft  104 . 
         [0053]    It is preferable that the user decouple the drive key  102  from the upper channel  108 C and the motor drive block  914  prior to applying manual force to the hand wheel  800  in an effort to manually turn the stem  116 . With the alternate version system  900  placed into the second operational mode, the resistance of the motor  106  to the rotation of the drive sprocket  108  is substantively eliminated, other that friction force evidenced between the drive shaft  104  and the drive sprocket  108 . 
         [0054]    Referring now generally to the Figures and particularly to  FIG. 10 ,  FIG. 10  is a top view of the alternate system  900  wherein the drive sprocket  108  and the driven sprocket  112  are shown to be entrained by the link chain  110 . 
         [0055]    Referring now generally to the Figures and particularly to  FIG. 11 ,  FIG. 11  is an exploded perspective view of the alternate system  900  that further includes an optional thrust valve  1000  that may be disposed between the top cover  902 B and the stem nut and through which the threaded stem  116  extends fully through. 
         [0056]    It is understood that the hand wheel aperture  800 A may be sized and shaped to extend about the stem  116  and engage with the Waterman/Fresno drive nut  904  sufficiently to enable transfer of manual force applied by the user to the hand wheel  800  to the threaded nut  114  and therefrom to the threaded stem  116 , whereby the user may manually position the threaded stem  116  alternately up and down the Y-axis. 
         [0057]    A motor housing back plate  1002  is coupled to the box bottom plate  902 A by the adjustable motor mount  908 . The motor housing back plate  1002 , the box bottom plate  902 A, the top cover  902 B, the adjustable motor mount  908  and the motor  106  are coupled into the configurations illustrated herein by fasteners, such as threaded bolts  1004  engaged with threaded apertures  1006 . 
         [0058]    Various elements  102 ,  104 ,  108  through  1004  of the preferred embodiments  100 ,  200  and  400  may be made of or comprise metal, such as stainless steel, and/or other suitable metal, metal alloy, plastic or other suitable material known in the art. 
         [0059]    The foregoing disclosures and statements are illustrative only of the present invention, and are not intended to limit or define the scope of the present invention. The above description is intended to be illustrative, and not restrictive. Although the examples given include many specificities, they are intended as illustrative of only certain possible applications of the present invention. The examples given should only be interpreted as illustrations of some of the applications of the present invention, and the full scope of the Present Invention should be determined by the appended claims and their legal equivalents. Those skilled in the art will appreciate that various adaptations and modifications of the just-described applications can be configured without departing from the scope and spirit of the present invention. Therefore, it is to be understood that the present invention may be practiced other than as specifically described herein. The scope of the present invention as disclosed and claimed should, therefore, be determined with reference to the knowledge of one skilled in the art and in light of the disclosures presented above.