Patent Publication Number: US-11646002-B2

Title: Capo for use with a stringed musical instrument, and method of using same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based upon, and claims priority from U.S. Provisional Patent Application No. 63/144,011, filed Feb. 1, 2021. The entire contents of the referenced priority application is incorporated by reference herein. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a capo for use with a stringed musical instrument having a neck portion including a fretboard, and a plurality of strings extending parallel to one another adjacent the fretboard, and to a method of using the capo. 
     2. Description of the Background Art 
     A number of different capos are known for use with stringed musical instruments, particularly guitars, banjos and the like, which have a neck portion including a fretboard on which the strings are played. The capo is a clamping device which fits on the instrument neck, that interacts with the underside of the neck below the fretboard, and which is used to selectively clamp the strings against the fretboard so as to alter the effective length of vibration of the strings, and thereby to selectively raise the respective tones produced by the instrument. 
     The capo allows for selective alteration of the tonality of the strings without affecting the original tuning of the instrument. Thus, by placing the capo at a pre-selected location on the fretboard, a musician can play his/her instrument and produce a desired sound quality, since the pitch produced by the strings with the capo attached is different from the pitch produced by the stings with the capo absent. This allows a musician to temporarily change the effective key in which the instrument is playing. 
     A number of different capos are known and commercially available. 
     U.S. Pat. No. 608,278 to Benson, dated Aug. 2, 1898, discloses a capo having a generally U-shaped main body, a clamping bar connected to the upper portion of the main body for transversely contacting the fretboard strings, a foot for pressing against the underside of the fretboard, a screw operated clamping mechanism and a guide finger interconnected with the foot and the lower portion of the main body for keeping the foot from turning when the screw of the screw operated clamping mechanism is rotated to effect clamping of the clamping bar onto the strings. 
     U.S. Pat. No. 656,904 to Pletcher, dated Aug. 28, 1900, discloses a capo having a clamping bar for pressing transversely against the strings, a clasp member pivotally connected to the clamping bar, an arm member connected to one end of the clamping bar, and a spring steel clip pivotally connected with the arm and which is structured to selectively engage the clasp member. 
     U.S. Pat. No. 775,399 to Halladay, dated Nov. 22, 1904, discloses a capo having a clamping bar for transversely engaging the strings, an arm connected to the clamping bar, and a screw actuated lever clamp pivotally interconnected with the arm. 
     U.S. Pat. No. 1,007,960 to Moore, dated Nov. 7, 1911, discloses a capo having a clamping bar for transversely contacting the strings, a rod pivotally connected at either side of the clamping bar, and a screw operated foot pivotally connected to the free ends of the rods. 
     U.S. Pat. No. 4,104,947 to Oster, dated Aug. 8, 1978, discloses a capo having a U-shaped member of which the upper portion thereof serves as a clamping bar for transversely engaging the strings, two off-set resilient string engaging members, a screw operated clamping mechanism connected with the lower portion of the U-shaped member and a foot interconnected with the clamping mechanism and a central portion of the U-shaped member. 
     U.S. Pat. No. 4,250,790 to Shubb et al, dated Feb. 17, 1981, discloses a capo having a clamping bar with a resilient material for transversely contacting the strings, an arm connected to the clamping bar, a curved jaw pivotally connected to the arm for contacting the underside of the fretboard, a lever pivotally connected to the arm in spaced relation with respect to the curved jaw, and a screw mechanism interconnected with the lever. 
     U.S. Design Pat. No. D257,988 to Nakamoto, dated Jan. 20, 1981, discloses an ornamental design for a capo showing a yoke having a pivotally connected clamping bar for transversely contacting the strings, a releasable clasp mechanism for holding the clamping bar in fixed relation to the yoke, and a screw operated clamp mechanism which includes a foot for contacting the underside of the fretboard and guide rods for preventing the foot from rotating when the screw is rotated. 
     U.S. Design Pat. No. D281,508 to McKinney, III, dated Nov. 26, 1988, discloses an ornamental design for a capo showing a yoke having a pivotally connected clamping bar for transversely contacting the strings, a releasable clasp mechanism for holding the clamping bar in fixed relation to the yoke, and a screw operated clamp mechanism which includes a foot for contacting the underside of the fretboard and a guide member for preventing the foot from rotating when the screw is rotated. 
     U.S. Design Patent D446,540 issued Aug. 14, 2001 to Elliott discloses another ornamental capo design. 
     U.S. Pat. No. 5,081,894 to Paige, issued Jan. 21, 1992, discloses a capo including a semi-circular yoke, a clamping bar pivotally connected to a first fork of the yoke and releasably interlocked at the second end to a second fork of the yoke via intermeshing of opposing slots, a clasp mechanism for releasably locking onto an end of the clamping bar, a screw-operated foot connected with the yoke, and dual guide clamping bars connected at either side of the foot which movably engage slots in the yoke. The capo of this reference engages the strings uniformly and simultaneously as the screw is tightened. 
     U.S. Pat. No. 7,973,227 to Paige discloses another capo design which includes a quick coarse adjustment feature and a fine adjustment feature which permits quick installation of the capo on an instrument. Other capo patents to Paige include 10,810,975 and 11,138,958. 
     While the foregoing examples of capos and other tools are usable for their intended purposes, a need still exists in the art for an improved capo. In particular, there is a need for an improved capo, and method of using same, which includes a clamping bar provided with a plurality of independent string-contacting members. 
     A need also exists for a capo and method of using the capo including a clamping bar assembly having a main bar body and a plurality of separate string clamp members formed of a durable, substantially rigid plastic material, where the string clamp members are operatively attached to the main bar body and at least one flexibly resilient cushion member is provided between the string-contacting members and a main bar body. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide an improved capo which includes a clamping bar having a separate, self-adjusting string-contacting member for each string. 
     A capo according to a first illustrative embodiment of the invention includes a yoke having a central support member, a string-contacting clamping bar which is pivotally attached to a branch of the yoke, a plurality of string-contacting members attached to the clamping bar, and at least one resilient cushion member disposed between the clamping bar and one or more of the string-contacting members. 
     The capo according to the first illustrative embodiment of the invention, also includes a substantially Y-shaped saddle member, including a stem which slidably fits through a second hollow bore of the central support member, a seat portion which is configured to contact a neck of an instrument, and an adjustment member for positioning the saddle member in the yoke. 
     The yoke according to the first illustrative embodiment is substantially U-shaped, and includes a central support member, with a first hollow bore formed therein defining a first axis, and having a back wall therein at the innermost portion of the first hollow bore. The central support member also has a second hollow bore formed therethrough, defining a second axis which is substantially perpendicular to the first axis, where the second hollow bore intersects the first hollow bore. 
     The yoke according to the first illustrative embodiment also includes a first yoke branch extending outwardly on one side of the central support member, and a second yoke branch extending outwardly on the other side of the central support member. The first yoke branch has a first yoke branch end with a first opening formed therein to receive a pivot member. 
     The capo according to the first illustrative embodiment also includes a clamping bar pivotally attached to the yoke, the clamping bar including a main bar body having a first end and a second end, the first end of the clamping bar being pivotally connected to the first branch end of the yoke, and the second end of the clamping bar is operatively engagable with the nesting notch of the yoke&#39;s second branch. 
     The capo according to the first illustrative embodiment also includes a latch structure pivotally attached to the second branch end of the yoke for releasably engaging the second end of the clamping bar to temporarily and releasably lock the second end of the clamping bar to the second branch end of the yoke. 
     The clamping bar assembly according to the first embodiment of the invention also includes a plurality of individual string clamp members, each of the string clamp members being formed separately from and movable independently of any adjacent string clamp members. Each of the string clamp members is configured to be slidably movable in relation to the main bar body, and each of the string-contacting members has a hollow passage formed therethrough. Each of the string clamp members has a cushion-contacting portion and a string-contacting portion spaced away from the cushion-contacting portion. 
     The capo according to the first embodiment of the invention also includes at least one resilient cushion member disposed between the main bar body and the cushion-contacting portion of at least one of the string clamp members. A single cushion member may extend the length of the main bar body and contact multiple string clamp members, or alternatively, each of the string clamp members may be provided with its own corresponding cushion member. 
     In the first illustrative embodiment of the invention, the main bar body of the capo&#39;s clamping bar has a plurality of sockets formed therein extending substantially parallel to one another, each of the sockets having a floor and being configured to receive a string clamping member. The main bar body further has a plurality of hollow bores formed therethrough, each of the bores intersecting a respective one of the sockets at a substantially 90 degree angle. 
     Also in the first illustrative embodiment of the invention, the capo&#39;s clamping bar includes a plurality of resilient cushion members in a number corresponding to the plurality of sockets, where each of the sockets receives a cushion member therein proximate the socket floor. 
     Further in the first illustrative embodiment of the invention, the capo&#39;s clamping bar further includes a plurality of string clamp inserts, each of the inserts having a cushion-contacting end and a string-contacting end opposite the cushion-contacting end. Each of these string clamp inserts is configured to fit slidably inside a respective one of the sockets of the main bar body, and each of the string clamp inserts has a central slot formed therethrough and configured to receive a cylindrical shaft of a fastener. 
     Still further in the first illustrative embodiment of the invention, the capo&#39;s clamping bar further includes a plurality of fasteners, with each of the fasteners having a cylindrical shaft which passes through one of the hollow bores of the main bar body and through the slot of a corresponding one of the inserts to slidably retain the corresponding insert in a respective one of the sockets of the main bar body. 
     In a second illustrative embodiment of the invention, the main bar body of the capo&#39;s clamping bar is a metal bar having a rectangular cross-section. 
     Further in the second illustrative embodiment of the invention, the capo further includes a plurality of separate string clamping members, each having a cushion-contacting portion and a string-contacting portion spaced away from the cushion-contacting portion. Each of the string-contacting portions has an arcuate string-contacting surface on an outer end thereof. 
     Each of these string clamping members is configured to slidably fit on to the main bar body, and each of the string clamping members has a central slot formed laterally therethrough, including an upper portion configured to allow the string clamping member to be slidably fitted on to the clamping bar&#39;s main bar body. The central slot also includes a lower portion which is configured to slidably receive a portion of an elongated cushion member therethrough, where a single cushion member extends through all of the string clamping members. The upper and lower portions may be the same with or different widths. Optionally, the upper portion, which receives the main bar body, may be narrower than the lower portion which receives the cushion member. 
     The cushion member and the string clamping members may be configured so that the string clamping members are retained on the main bar body by an interference fit between the cushion member, the main bar body and the string clamping members. 
     The present invention also provides methods of using the inventive capo. 
     Additional embodiments of the present invention are also contemplated, and are described herein in the detailed description section. 
     For a better understanding of the present invention, the reader is referred to the following detailed description section, which should be read in conjunction with the accompanying drawings. Throughout the following detailed description and in the drawings, like numbers refer to like parts. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is an environmental perspective view, partially cut away, of a guitar neck having a capo installed thereon according to a first illustrative embodiment of the present invention. 
         FIG.  2    is a perspective view of the capo of  FIG.  1   , shown separately from the guitar. 
         FIG.  3 A  is a detail perspective view of the capo of  FIGS.  1 - 2   , shown in a partially open position. 
         FIG.  3 B  is a detail view of one end portion of a yoke portion of the capo of  FIGS.  1 - 2   . 
         FIG.  4 A  is an exploded perspective view of a clamping bar assembly, which is a component of the capo of  FIGS.  1 - 3 B . 
         FIG.  4 B  is a perspective view of a string clamp insert which is a component part of the clamping bar assembly of  FIG.  4 A . 
         FIG.  5 A  is a side plan view of a main bar member which is a sub-component of the clamping bar assembly of  FIG.  4 A , with a number of hollow sockets shown in phantom. 
         FIG.  5 B  is a bottom plan view of the main bar member of  FIG.  5 A . 
         FIG.  6 A  is a side plan view of a locking clip which is another component of the capo of  FIGS.  1 - 3 B . 
         FIG.  6 B  is a top plan view of the locking clip of  FIG.  6 A . 
         FIG.  7 A  is a side plan view of another capo according to the first embodiment, having a modified yoke and latch assembly, and also showing string clamping members separate from a main bar member of a clamping bar assembly. 
         FIG.  7 B  is a side plan view of a yet another capo  20 T according to a modified version of the first embodiment, also showing a cross-sectional view of an instrument which has the capo mounted thereon, the capo having string clamping members modified to fit on a 12-string guitar. 
         FIG.  7 B  also includes an enlarged inset of a circled portion of the drawing. 
         FIG.  7 C  is a side plan view of the capo of  FIG.  7 B , also showing the string clamping members separate from a clamping bar assembly. 
         FIG.  7 D  is a perspective view of the capo of  FIGS.  7 B- 7 C , taken from a vantage point below and to the side of the capo. 
         FIG.  7 E  is a side plan view of another capo according to the first embodiment hereof, configured to fit across four strings of a five-string banjo and having a modified yoke and latch assembly, also showing string clamping members separate from a clamping bar assembly. 
         FIG.  8    is a perspective view of another capo according to a second embodiment of the present invention. 
         FIG.  9    is a detail perspective view of the capo of  FIG.  8   , shown in an open position and with an adjustment member at the lower end omitted from the drawing for purposes of illustration. 
         FIG.  10    is a detail perspective view of a main bar body, which is a component part of the capo of  FIG.  8   , having a single string clamping member and a cushion member attached thereto. 
         FIG.  11 A  is a perspective view of a single string clamping member which is a component part of the capo of  FIG.  8   . 
         FIG.  11 B  is a side plan view of the string clamping member of  FIG.  11 A ; and. 
         FIG.  11 C  is an end plan view of the string clamping member of  FIG.  11 A . 
     
    
    
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     Descriptions will be provided below of selected illustrative embodiments of the present invention on a basis of examples of the invention, supported by and shown in the accompanying drawings. It should be understood that only structures considered necessary for clarifying the present invention are described herein. Other conventional structures, and those of ancillary and auxiliary components of the system, will be known and understood by those skilled in the art. 
     Throughout the present specification, relative positional terms like ‘upper’, ‘lower’, ‘front’, ‘rear’, ‘top’, ‘bottom’, ‘horizontal’, ‘vertical’, and the like are used to refer to the orientation of the capo apparatus and components as shown in the drawings. These terms are used in an illustrative sense to describe the depicted embodiments, and are not meant to limit the invention. It will be understood that the depicted apparatus and components thereof may be placed at orientations different from that shown in the drawings, such as inverted 180 degrees or transverse to that shown, and in such a case, the above-identified relative positional terms will no longer be accurate. 
     While the drawings and description herein describe the capo as used with a stringed instrument such as a guitar, it should be understood that the stringed musical instrument does not form part of the invention, per se, but instead, the stringed instrument constitutes a workpiece on which the capo hereof is applied. 
     First Embodiment 
     Referring now to the drawings,  FIG.  1    generally shows a capo  20  according to a first illustrative embodiment of the present invention, in operation on a fretboard  14  situated on one side of a neck  12  of a stringed instrument  10 , and compressing portions of the strings  16 . 
     Referring also to  FIGS.  2  and  3 A , the capo  20  includes three main parts, a yoke  22 , a clamping bar assembly  40  pivotally attached to the yoke, and an adjustment mechanism  37  which is adjustably connected to the yoke. The adjustment mechanism  37  includes a saddle member  31  which is configured to contact an underside of the instrument&#39;s neck  12 . 
     The yoke  22  is a substantially U-shaped member, as shown, including a central support member  23 , as well as first and second yoke branches  26 ,  28  respectively attached to opposite sides of the central support member  23 . The clamping bar assembly  40  is pivotally connected to an outer end portion  26   a  of the first yoke branch  26 . 
     The adjustment mechanism  37  includes the saddle member  31 , having a central shaft  32  which fits through a hollow bore formed in the central support member  23  of the yoke  22 . The adjustment mechanism  37  also includes an adjustment member  70 , which may be rotatably attached to the saddle member  31  in a manner so as to allow linear movement of the saddle member in relation to the central support member  23  of the yoke  22 . The adjustment member  70  may include a thumbscrew or handle member  72  as shown. 
     The adjustment member  70  is adjustably connected to the central support member  23  of the yoke  22 , as will be further described herein. A number of different configurations may be used for structure and operation of the yoke and adjustment member, as described in U.S. Pat. Nos. 7,973,227, 10,810,975 and 11,138,958, the entire disclosures of which are incorporated by reference herein. 
     One such modified configuration of the adjustment member, in which the central section of the yoke has a rectangular passage formed therethrough to receive and house a cylindrical adjustment nut, is shown in  FIGS.  7 A- 7 E  of the drawings. 
     As can be seen from  FIG.  1   , when the capo  20  is installed on an instrument  10 , the clamping bar assembly  40  extends transversely across the strings  16  of the fretboard  14 . When the capo  20  applies a clamping force onto the strings  16 , they are forced against the fretboard, thereby effectively changing the vibration length of the strings and changing the effective key of the instrument. 
     The compressive force of the clamping bar assembly  40 , pressing onto the strings  16 , is reinforced by a seat portion  33  of the saddle member  31  being squeezed against the back of the neck portion  12  of the instrument. The position of this saddle member  31  is adjusted through operation of the adjustment member  70 , which is adjusted to cause the linked saddle member  31  to move with respect to the yoke  22 , until the saddle member  31  and the clamping bar assembly  40  cooperate to clamp the instrument neck therebetween, and apply a sufficient compressive force to the strings. 
     Further details of each of the structural components of the capo  20  according to the first embodiment of the invention will be described below. 
       FIG.  2    is a perspective view of the capo of  FIG.  1   , shown separately from the guitar, and  FIG.  3 A  is a detail perspective view of the capo of  FIG.  2   , shown in a partially open position. 
     In  FIG.  2    of the drawings, the capo  20  according to the first embodiment of the present invention is shown separately from the instrument  10 . As noted above, the generally U-shaped yoke  22  includes the central support member  23  and the first and second yoke branches  26 ,  28  extending outwardly from opposed sides of the central support member. 
     The clamping bar assembly  40  is pivotally attached to an upper end  26   a  of the first yoke branch  26  by a pivot connection  30 . As shown in  FIG.  3 A , a free end  42  of the clamping bar assembly  40 , opposite the pivot connection, has an open engagement notch  40   n  formed therein, and is selectively attachable to the second yoke branch  28  by a latching clip  90 , as will be further described herein. 
     The yoke  22  may be constructed of stainless steel, and is configured and dimensioned to generally fit about the neck portion of a stringed musical instrument  10  such a guitar, as shown in  FIG.  1   . The yoke  22  is formed in an arcuate curvilinear U-shape, which is modified to have locally linear segments at the central support member  23  and adjacent each of the respective outer end portions  26   a  and  28   a  of the first and second yoke branches  26  and  28 , respectively. 
     The yoke  22  includes the first yoke branch  26  extending outwardly on a first side of the central support member  23 , and a second (free) yoke branch  28  extending outwardly on the other side of the central support member. 
     As shown in the detail view of  FIG.  3 B , the first yoke branch  26  includes a first yoke branch end  26   a  having a notch  25  formed therein, and also having a hollow bore  38  formed therein to receive a cylindrical shaft  30   s  of the pivot member  30 , so that a main bar body  43  of the clamping bar assembly  40  may be pivotally connected to the first yoke branch  26 . 
     Clamping Bar Assembly 
     Referring now to  FIG.  4 A , in the capo according to this first embodiment of the invention, the clamping bar assembly&#39;s main bar body  43  has a first end  41  with a hole  36  formed therethrough to receive the shaft  30   s  of the pivot member  30 . With the main bar body  43  aligned with the yoke  22 , the shaft  30   s  ( FIG.  3 B ) of the pivot member  30  is inserted into and through the respective holes  36 ,  38  to pivotally attach the main bar body  43  of the clamping bar assembly  40  to the yoke  22 . The pivot member  30  may be a rivet, screw or other fastener known in the art, creating a relatively permanent pivot connection between the yoke  22  and the clamping bar assembly  40 . 
     The main bar body  43  of the clamping bar assembly  40  also has a second end  42  opposite the first end, the second end being operatively engagable with a nesting notch  29  ( FIG.  3 A ) formed in the upper end  28   a  of the second yoke branch  28 , to allow a user to temporarily and releasably lock the clamping bar assembly  40  in place on the yoke  22 . The second end  42  of the main bar body  43  may also be referred to as the free end. 
     The clamping bar assembly  40  is pivotally movable between a closed position, shown in  FIG.  2    of the drawings, and an open position shown in  FIG.  3 A , with the clamping bar assembly rotated on the pivot member  30  away from the second yoke branch  28 . In the open position of the clamping bar assembly  40 , the second (free) end  42  thereof moves away from the yoke&#39;s second branch portion  28 , and a space  21  between the branches  26 ,  28  of the yoke is uncovered to permit placement of the capo on an instrument&#39;s neck  12 . 
     Referring also to  FIGS.  5 A, and  5 B , it will be seen that in this first illustrative embodiment of the capo according to the present invention, the main bar body  43  of the capo&#39;s clamping bar assembly  40  has a plurality of hollow sockets  40   s  formed therein and extending substantially parallel to one another. Each of these sockets  40   s  has a floor  43   f  ( FIG.  5 A ), and is configured to receive a base portion  82  of a string clamp insert  80  ( FIGS.  4 A,  4 B ) therein. The main bar body  43  further has a plurality of hollow mounting bores  43   b  formed therethrough, each of the mounting bores transversely intersecting a longitudinal axis of a respective one of the sockets  40   s , as shown. 
     As shown in  FIG.  4   , the capo&#39;s clamping bar assembly  40  further includes a plurality of resilient cushion members  44 , in a number corresponding to the plurality of sockets  40   s . Each of the sockets receives a cushion member  44  therein proximate the socket floor  43   f . These cushion members  44  may be formed of rubber or a suitable elastomer. Alternatively, the cushion members  44  may be springs such as, for example, bow-shaped leaf springs (not shown). 
     The capo&#39;s clamping bar assembly  40  further includes a plurality of substantially identical string clamp inserts  80 , which provide string clamping members. The string clamp inserts  80  are formed from a strong plastic material such as polyether ether ketone (PEEK), or polyetherimide, which is sold under the brand Ultem®. 
     As seen best in  FIG.  4 B , each of the inserts  80  bay be formed in an inverted T-shape having a relatively narrow base portion  82  with a cushion-contacting end  83 . The base portion  82  of each of these string clamp inserts  80  is configured to fit slidably inside a respective one of the sockets  40   s  of the main bar body  43 , with one of the resilient cushion members  44  disposed between the insert and the floor  43   f  of the socket. 
     Each string clamp insert  80  also has a widened string-contacting portion  84  which provides a string-contacting end opposite the cushion-contacting end  83 . The outer surface of the string-contacting portion  84  may be formed as an arcuate concave string-contacting surface  85 , which helps to align a corresponding one of the strings  16  to a central portion of the insert  80  during use of the capo  20 . 
     If desired, the string clamp inserts  80  may be made in a modified rectangular shape, where the string-contacting portion has the same width as the base portion, as shown in  FIG.  7 A . 
     Each of the string clamp inserts  80  also has a hollow central slot  86  formed therethrough and extending vertically therein, as shown, to receive a cylindrical shaft of another fastener  40   f  ( FIG.  4 A ) therethrough. During use of the capo  20 , the slot  86  permits the string clamp insert  80  to slidably move in relation to the main bar body  43  by a limited distance, separate from and substantially independently of the other string clamp inserts, while remaining operatively attached to the main bar body. 
     As best seen in  FIG.  4 A , the capo&#39;s clamping bar assembly  40  further includes a plurality of fasteners  40   f , which may be roll pins, rivets, or other suitable fasteners known in the art. Each of the fasteners  40   f  has a cylindrical shaft which passes through one of the hollow bores  43   b  of the main bar body  43 , and also through the slot  86  of a corresponding one of the spring clamp inserts  80 , to slidably retain the spring clamp insert in a respective one of the sockets  40   s  of the main bar body  43 . 
     Latch Structure 
     The capo according to the first illustrative embodiment also includes a latch structure, including a locking clip  90  which is pivotally attached to the second branch end  28   a  of the yoke, for selectively and releasably engaging the second end of the clamping bar to temporarily and releasably lock the second end of the clamping bar to the second branch end. 
     Referring now to  FIGS.  6 A- 6 B  together with  FIG.  2   , the locking clip  90  is formed in a shape resembling a mirror image of the number  6 , having a circular base  92  at a lower end thereof with a mounting hole  94  formed therethrough, a central part  95  extending upwardly from one side of the circular base, and a curved latching finger  96  integrally attached to the upper end of the central part  95 . The latching finger  96  is selectively engagable in the notch  40   n  ( FIG.  3 A ) formed in the second end  42  of the main bar body  43 . 
     The central part  95  of the locking clip  90  may have a tab  97  extending outwardly thereon, and this tab  97  may be bent approximately 90 degrees from the rest of the latching clip, as shown, to provide a surface configured for a user to grasp when moving the clip into or out of engagement with the second end  42  of the main bar body  43 . 
     Modified Embodiments 
     A first modified embodiment of the capo  20  is shown in  FIG.  7 A , and includes an adjustment member in which the central section of the yoke has a rectangular passage formed therethrough to receive and house a cylindrical adjustment nut. This modified embodiment also uses inserts  80  which have a constant width, and places the locking clip  90  inside of another notch formed perpendicular to the nesting notch  29  inside of the second end of the yoke. 
     A second modified embodiment of a capo  20 T is shown in  FIG.  7 B- 7 D , and has the same modifications discussed above in connection with the first modified embodiment. In addition, this modified capo  20 T is specially designed for use with a 12-string guitar having six pairs of string sets, where each string set includes two closely-spaced strings such as those shown at  16   t  and  16   b , and for this reason, two different types of specialized string clamp inserts  80 T 1 ,  80 T 2  may be used. This 
     Each of the string clamp inserts  80 T 1 ,  80 T 2  may be modified so that the string-contacting surface thereof is provided with an integrally formed central spacer boss  80 B ( FIG.  7 C ) extending outwardly thereon from a central portion of the string-contacting surface  85 . During use of the capo of  FIGS.  7 B- 7 D  in a clamped position on a twelve-string guitar, this spacer boss  80 B keeps the two strings of its corresponding string pair properly spaced away from each other. 
     The lowermost (in tone) four pairs of strings on a twelve-string guitar include both a bass string such as  16   b , having a relatively large diameter, and a treble string such as  16   t , which has a smaller diameter and is tuned an octave higher than the bass string. As seen in the enlarged insert of  FIG.  7 B , the treble string  16   t  has a much smaller diameter than the bass string  16   b . For this reason, the inserts  80 T 2  used for the lowermost four string sets have a deeper recess  85   a   1  ( FIG.  7 C ) on a first side of the insert that contacts the bass string  16   b  of the pair, and a shallower recess  85   a   2  on a second side of the insert that contacts the treble string  16   t  of the pair, as shown. 
       FIG.  7 D  is a perspective view of the capo of  FIGS.  7 B- 7 C , taken from a vantage point below and to the side of the capo. 
       FIG.  7 E  is a side plan view of another modified capo  20 B according to the first embodiment of the present invention. This capo  20 B has the same modifications discussed above in connection with the first modified embodiment In addition, this modified capo  20 B only four string clamping members  80 , and is configured to fit across four strings of a five-string banjo.  FIG.  7 E  shows the string clamping members  80  separate from a main clamping bar of the clamping bar assembly. 
     Capo Operation 
     During installation of the capo  20  on an instrument  10 , the clamping bar assembly  40  is placed extending transversely across the strings  16  of the fretboard  14 , and is engaged with the second (free) end  28   a  of the yoke  22  by placing the second (free) end  42  of the main bar body  43  into the nesting notch  29  of the yoke, and then engaging the latching finger  96  of the latching clip  90  in the notch  40   n  of the main bar body  43 . 
     The adjustment member  70  can then be selectively rotated by manually turning the handle portion  72  to make a tightening adjustment. The position of the saddle member is adjusted through operation of the adjustment member  70 , which is adjusted to cause the saddle member  31  to slide axially in relation to the yoke  22  until the clamping bar assembly  40  applies a desired compressive force upon the strings. 
     Each of the string clamp inserts  80  is substantially independent of the other string clamp inserts  80 , and when the capo is clamped on to a musical instrument as shown in  FIG.  1   , each of the string clamp inserts  80  is individually movable based on an adjustment between the tension applied to the string-contacting surface  85  by the corresponding string or strings, and an opposite pressure applied to the cushion-contacting end  83  of the insert  80  by the corresponding cushion member  44 , which is under compression. 
     Second Embodiment 
     Referring now to  FIG.  8    of the drawings, another capo  120  according to a second illustrative embodiment of the present invention is shown separately from the instrument  10 . The capo shown in  FIG.  8    is also configured to fit on a banjo (not shown), and to clamp across four strings of the banjo. Accordingly, this capo only has for string clamp members  180  on its clamping bar assembly  140 . 
     This capo  120  also includes three main parts, a yoke  122 , a clamping bar assembly  140  pivotally attached to one side of the yoke, and an adjustment mechanism  137  including a saddle member  131  which is configured to contact an underside of a banjo neck (not shown). 
     The primary difference between the capos  20 ,  120  according to the first and second embodiments is that in the second embodiment, the clamping bar assembly  140  is quite different from the clamping bar assembly  40  of the first embodiment. 
     In a manner similar to that described above in connection with the first embodiment, the generally U-shaped yoke  122  includes a central support member  123  and the first and second yoke branches  126 ,  128  extending outwardly from opposed sides of the central support member. As noted above in connection with the first embodiment, a number of different configurations may be used for structure and operation of the yoke and adjustment member as described in U.S. Pat. No. 7,973,227 10,810,975 and 11,138,958, the entire disclosures of which are incorporated by reference herein. 
     The clamping bar assembly  140  is pivotally attached to the first yoke branch  126  by a pivot connection  130 . As shown in  FIG.  9   , a free end  142  of the clamping bar assembly  140 , opposite the pivot connection, has an open notch  140   n  formed therein, and is attachable to the second yoke branch  128  by a latching clip  90 , as described above in connection with the first embodiment. 
     The yoke  122  may be constructed of stainless steel, and is configured and dimensioned to generally fit about the neck portion of a standard stringed musical instrument such a banjo (not shown). The yoke  122  is formed in an arcuate curvilinear U-shape, which is modified to have locally linear segments at the central support member  123  and adjacent each of the respective outer end portions  126   a  and  128   a  of the first and second yoke branches  126  and  128 , respectively. 
     The yoke  122  includes the first yoke branch  126  extending outwardly on one side of the central support member  123 , and a second (free) yoke branch  128  extending outwardly on the other side of the central support member. As shown in the detail views of  FIGS.  9 - 10   , the first yoke branch  126  includes a first yoke branch end  126   a  having a notch  125  formed therein, and also having a hollow bore formed therein to receive a cylindrical shaft of the pivot member  130  therein, so that a main bar body  143  of the clamping bar assembly  140  may be pivotally connected to the first yoke branch  126 . This arrangement is similar to that of the yoke  22  according to the first embodiment, as previously described herein. 
     Referring also to  FIG.  10   , in the capo  120  according to the second illustrative embodiment of the present invention, the main bar body  143  of the clamping bar assembly  140  is a generally solid metal bar having a rectangular cross section. In the capo  120  according to this second embodiment of the invention, the clamping bar&#39;s main bar body  143  has a first end  141  with a hole formed therethrough to receive a shaft of the pivot member  130 . 
     The main bar body  143  of the clamping bar assembly  140  also has a second end  142  opposite the first end, the second end being operatively engagable with a nesting notch  129  formed in the upper end  128   a  of the second yoke branch  128 , to allow a user to temporarily and releasably lock the clamping bar assembly  140  in place on the yoke  122 . The second end  142  of the main bar body  143  may also be referred to as the free end, because it is not permanently connected to the yoke  122 . 
     With the main bar body  143  aligned with the yoke  122 , the shaft of the pivot member  130  (similar to that shown at  30   s  in  FIG.  3 B ) is inserted into the respective holes to pivotally attach the clamping bar assembly  140  to the yoke  122 . The pivot member  130  may be a rivet, screw or other fastener known in the art, creating a relatively permanent pivot connection between the yoke  122  and the clamping bar assembly  140 . 
     The clamping bar assembly  140  is pivotally movable between a closed position, shown in  FIG.  8    of the drawings, and an open position shown in  FIG.  9   , with the clamping bar rotated on the pivot member  130  away from the second yoke branch  128 . In the open position of the clamping bar assembly  140 , the second end  142  thereof extends away from the yoke&#39;s second branch portion  128 , and a space between the branches  126 ,  128  of the yoke  122  is uncovered to permit placement of the capo on an instrument&#39;s neck. 
     Referring also to  FIGS.  11 A- 11 C , it will be seen that in this second illustrative embodiment of the capo  120  according to the present invention, the clamping bar assembly  140  includes a plurality of individual string clamp members  180 , each of the string clamp members being formed separately from and movable independently of adjacent string clamp members. 
     As seen best in  FIGS.  11 A- 11 C , each of the string clamp members  180  has a cushion-contacting portion  183  and a string-contacting portion  184  spaced away from the cushion-contacting portion. The string-contacting portion  184  includes an arcuate string-contacting surface  185 . 
     Each of the string clamp members  180  has a hollow passage  186  formed therethrough to permit the string clamp member to receive both the clamping bar&#39;s main bar body  143  and an elongated cushion member  144  therethrough, in such a manner as to permit the string clamp members  180  be slidably movable on the main bar body  143 . The hollow passage  186  includes both a first portion  187  configured to receive the main bar body  143 , and a second portion  188  configured to receive part of the elongated cushion member  144 . While these two portions  187 ,  188  of the hollow passage are shown to have different widths in  FIGS.  11 A and  11 C , it is contemplated that they may have the same width without departing from the scope of the invention. 
       FIG.  10    illustrates a single string clamp member  180  disposed on the main bar body  143  during initial assembly of the capo  120 , and clearly shows the elongated cushion member  144 , which is shared between all of the string clamp members  180 . As seen best in  FIG.  10   , the capo&#39;s clamping bar assembly  140  further includes the elongated resilient cushion member  144 , which slidably fits through the second portion  186  of each of the individual string clamp members  180 . This cushion member  144  may be formed of rubber or a suitable elastomer. Alternatively, the cushion member  144  may be replaced by a plurality of springs such as, for example, bow-shaped leaf springs, held in place in a manner which will be understood by those in the art. 
     Capo Operation 
     During installation of the capo  120  on an instrument (not shown), the clamping bar assembly  140  is placed extending transversely across the strings  16  of the fretboard  14 , and is engaged with the free end  128   a  of the yoke  122 . The adjustment member  170  can then be selectively rotated by manually turning the handle portion  172  to make a tightening adjustment. The position of the saddle member is adjusted through operation of the adjustment member  170 , which is adjusted to cause the saddle member  131  to slide with respect to the yoke  122  until the clamping bar assembly  140  applies a desired compressive force upon the strings. 
     Each of the string clamp members  180  is made separate from the other string clamp members, and is movable substantially independently of the other string clamp members, to clamp its corresponding string or strings. 
     Method of Using the Capo 
     The capo  120  is used in a manner similar to that described above in connection with the capo  20  according to the first embodiment. 
     Although the present invention has been described herein with respect to a number of specific illustrative embodiments, the foregoing description is intended to illustrate, rather than to limit the invention. Those skilled in the art will realize that many modifications of the illustrative embodiment could be made which would be operable. All such modifications, which are within the scope of the present description, are intended to be within the scope and spirit of the present invention.