Patent Publication Number: US-7223910-B2

Title: Snare drum

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a snare drum, and more particularly, to a snare drum of a type having a plurality of snare wires held by a frame. 
     A snare drum having a plurality of snare wires on a lower head face is known in the prior art (see U.S. Pat. No. 1,832,227). 
       FIG. 19  is a perspective view showing a snare wire unit  211  of a first prior art example.  FIG. 20  is a view of a snare drum  200  to which the snare wire unit  211  is attached, as seen from the lower side of the drum  200 . As shown in  FIG. 19 , the snare wire unit  211  has a plurality of snare wires  201 , and a right metal holder  202  and a left metal holder  203  for holding opposite ends of the snare wires  201 . In the prior art snare drum  200 , the metal holders  202  and  203  are respectively inserted into and fastened to a right connector  205  and a left connector  206 , which are located on a lower hoop  204  of the drum  200 . The right connector  205  has an opening in its right face so that the snare wire unit  211  can be inserted into and removed out through the opening. A threaded hole (not shown) is formed in the left face of the left metal holder  203 . A bolt  207  provided in the left connector  206  is engaged with the threaded hole to fasten the left metal holder  203  and the left connector  206  together to each other. Further, a switch  210  is connected to the left connector  206  for bringing the snare wires  201  close to the lower head  209 . 
     To remove the snare wire unit  211  from the snare drum  200 , the bolt  207  is first loosened and the left metal holder  203  is pulled in the rightward direction out of the left connector  206 . The right metal holder  202  is then pulled in the rightward direction out of the right connector  205 . To attach the snare wire unit  211  to the snare drum  200 , the left metal holder  203  is first inserted through the right connector  205  from the right side to the left side. Then, the left metal holder  203  is inserted into the left connector  206  from the right side to the left side. The bolt  207  is then tightened to fasten the left metal holder  203  to the left connector  206 . This also fastens the right metal holder  202  to the right connector  205  The snare wire unit  211  is attached to the snare drum  200  in this manner. 
     There is a second prior art example, in which snare wires are held by a frame and the frame is supported by a string on the drum (see U.S. Pat. No. 3,113,481). To remove a snare wire unit, which includes a plurality of snare wires and the frame, from the snare drum, the string is first loosened. Then, the unit is detached from the drum. 
     Detachment and attachment of the snare wire unit becomes necessary when replacing, for example, a lower head or individual snare wires. In the first and second prior art examples, however, a series of tasks as described above must be performed to detach and attach the snare wire unit. These tasks are complicated and troublesome. 
     Further, in the first prior art example, once the snare wire unit  211  is removed, the tension of the snare wires  201  drops to zero. This means that the adjusted tension before detachment of the snare wire unit  211  cannot be maintained. Thus, tension adjustment must be performed again after the attachment. It is inefficient and troublesome to perform tension adjustment every time the snare wire unit is detached and attached. Moreover, since the fastening with the bolt  207  of the left connector  206  applies tension to the snare wires  201  in addition to fixing the left metal holder  203  to the left connector  206 , the tension of the snare wires  201  is directly applied to the switch  210  and the body of the drum  200 . This results in various problems, such as much strength being required to operate the switch  210  and deformation of the drum body occurring. 
     Further, the opposite ends of the plurality of snare wires  201  are all fixed to the metal holders  202  and  203  so that the snare wires  201  do not become scattered when the snare wire unit  211  is detached from the drum. Therefore, the snare wires cannot be replaced individually. The number of the snare wires is usually about ten to fourteen. However, when there is no need to use, for example, four to eight snare wires, the unnecessary snare wires must be cut off. However, once the wires are cut off, it is impossible to restore the cut off wires when the original number of snare wires becomes necessary. 
     The second prior art example differs from the first prior art example in that the snare wires are held by the frame and the tension of the snare wires is thus maintained even after detachment of the snare wire unit. However, the string fastens the frame to the drum. Thus, it is difficult to adjust the position of the string accurately. Consequently, there is a problem in that a slight difference in the position of the snare wire unit before and after the detachment occurs. Further, especially when the snare drum is used as a marching snare drum, there is a problem in that the string is often broken due to heavy vertical and horizontal swaying motions during usage of the drum. 
     It is an object of the present invention to provide a snare drum which eliminates the need for tension adjustment when reattaching snare wires which have been detached and which simplifies the attachment and detachment of snare wires to a drum. A further object of the present invention is to provide a snare drum that enables snare wires to be replaced individually. 
     SUMMARY OF THE INVENTION 
     To achieve the above objects, the present invention provides a snare drum for use with a plurality of snare wires. The snare drum includes a drum shell having an upper head and a lower head mounted thereon, an outer side, and a frame for holding the plurality of snare wires. The frame arranging the snare wires to be in contact with the lower head or to be spaced from the lower head. The snare drum includes a first latched member and a second latched member respectively located at opposite ends of the frame at the outer side of the drum shell. An attachment mechanism is located on the drum shell for arranging the frame on a surface of the lower head. The attachment mechanism includes a first latching member and a second latching member arranged between the drum shell and the first and second latched members for separably latching the first and second latched members, respectively. 
     Other aspects and advantages of the present invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention, together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which: 
         FIG. 1  is a lower perspective view showing a snare drum according to a preferred embodiment of the present invention; 
         FIG. 2  is a front view showing the snare drum; 
         FIG. 3  is a bottom view showing the snare drum; 
         FIG. 4  is a rear perspective view showing the snare drum; 
         FIG. 5  is an enlarged cross-sectional view taken along line  5 — 5  in  FIG. 2  and mainly shows a head adjuster; 
         FIG. 6  is a perspective view showing a frame; 
         FIG. 7  is perspective view showing a first individual adjustment piece for a snare wire; 
         FIG. 8  is a perspective view showing a second individual adjustment piece for a snare wire; 
         FIG. 9  is a cross-sectional side view of the frame; 
         FIG. 10  is a plan view showing the frame; 
         FIG. 11  is a bottom view showing the frame; 
         FIG. 12  is a cross-sectional view taken along line  12 — 12  in  FIG. 11  and shows a damper; 
         FIG. 13  is a cross-sectional view taken along line  13 — 13  in  FIG. 12  and shows the damper; 
         FIG. 14  is a cross-sectional view showing a frame attachment mechanism in a state in which an operation lever is located at the lowermost position; 
         FIG. 15  is a cross-sectional view showing a frame attachment mechanism in a state in which the operation lever is located at the uppermost position; 
         FIG. 16  is a partial cross-sectional view taken along line  16 — 16  in  FIG. 15 ; 
         FIG. 17  is a front view showing a slide member; 
         FIG. 18  is a perspective view showing a latching member; 
         FIG. 19  is a perspective view showing a snare wire unit according to a first prior art example; and 
         FIG. 20  is a bottom view showing the snare drum of the first prior art example. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A preferred embodiment of a snare drum  1  according to the present invention will now be described with reference to  FIGS. 1 through 18 . The snare drum  1  includes a snare wire unit. 
     As shown in  FIGS. 1 and 2 , a snare drum  1  (hereafter, simply referred to as “drum”) has a cylindrical drum shell  2 , the upper and lower ends of which are open. The open upper and lower ends of the drum shell  2  are closed by disk-like upper head  3  (see  FIG. 2 ) and a disk-like lower head  4  that are fixed to the drum shell  2  by an upper hoop  23  and a lower hoop  25 , respectively. A plurality of (twelve in this embodiment) head adjusters  5  for adjusting the tension applied to the upper and lower heads  3  and  4  are arranged at equal angular intervals along the peripheral wall of the drum shell  2  so as to connect the upper hoop  23  and the lower hoop  25 . 
     A plurality of snare wires  7 , which are formed from stringing, are held by a snare wire unit frame  6  and are arranged on the lower head  4  to extend diametrically across the lower head  4 . Additionally, as shown in  FIGS. 1 and 3 , dampers  8  are arranged at opposite sides of the frame  6  to adjust resonance when playing the drum  1  with the snare wires  7 . 
     Further, as shown in  FIG. 2 , an attachment mechanism  10  is secured to the peripheral wall of the drum shell  2  so that the frame  6  can be attached to and detached from the drum shell  2 . The attachment mechanism  10  includes an operating mechanism  11  (on the right side in  FIG. 2 ) and a fixing mechanism  12  (on the left side in  FIG. 2 ). The operating mechanism  11  and the fixing mechanism  12  are arranged at two positions located at opposite sides of the drum  1 , or spaced by 180 degrees from each other with respect to the center of lower head  4 . The operating mechanism  11  has a switching device  13  for switching the frame  6  between an engagement state in which the snare wires  7  are in contact with the lower head  4  and a disengagement state in which the snare wires  7  are separated from the lower head  4 . The switching device  13  is operated by a pivotal operation lever  14 . 
     A lower ring member  16  extends around the lower part of the drum shell  2  in a state slightly spaced from the peripheral wall of the shell  2 . Four legs  17  are arranged along the lower ring member  16  in a symmetric manner (see  FIG. 3 ). 
     As shown in  FIG. 4 , when the snare drum  1  is used as a marching snare drum, a carrier attachment component  19  is fastened to the rear of the drum shell  2  by a plurality of screws  19   a  so that a carrier  18  can be attached to the carrier attachment component  19 . 
     The head adjusters  5 , the frame  6 , the damper  8 , and the frame attachment mechanism  10  will now be described one by one in detail. 
     (Head Adjuster  5 ) 
       FIG. 5  shows a state in which the drum  1  of the present embodiment is placed on a flat surface such as a floor. As shown in  FIG. 5 , an annular reinforcing ring (upper ring member)  21  is arranged at the upper part of the drum shell  2  to be fitted to the peripheral wall of the drum shell  2 . An annular upper head frame  22  is fitted to the peripheral wall of the drum shell  2  on the outer side of the reinforcing ring  21 . The upper head frame  22  holds the periphery of the upper head  3 . An annular upper hoop  23  fitted to the peripheral wall of the drum shell  2  is arranged on the outer side of the upper head frame  22 . In the same manner, the periphery of the lower head  4  is held by an annular lower head frame  24  fitted to the peripheral wall of the drum shell  2 . An annular lower hoop  25  is fitted to the peripheral wall of the drum shell  2  on the outer side of the lower head frame  24 . 
     Each head adjuster  5  includes a hollow cylindrical tension pipe  20 , an upper tension bolt  26  for connecting the tension pipe  20  with the upper hoop  23 , and a lower tension bolt  27  for connecting the tension pipe  20  with the lower hoop  25 . The tension pipe  20  is located between the reinforcing ring  21  and the ring member  16 . 
     The tension pipe  20  and the upper tension bolt  26  are coupled together by an upper tension nut  28 . The tension pipe  20  and the lower tension bolt  27  are coupled together by a lower tension nut  29 . The upper tension nut  28  is inserted into the upper part of the tension pipe  20  and engaged with the upper tension bolt  26  which is inserted into the tension pipe  20  from above the upper tension nut  28 . The lower tension nut  29  is inserted into the lower part of the tension pipe  20  and engaged with the lower tension bolt  27  which is inserted into the tension pipe  20  from below the lower tension nut  29 . The upper surface of the body  28   a  of the upper tension nut  28  contacts the lower surface of the reinforcing ring  21 . The upper surface of the body  29   a  of the lower tension nut  29  contacts the lower surface of the ring member  16 . 
     A metal washer  30  and a brass washer  31  are arranged between the upper hoop  23  and a bolt head  26   a , which serves as a rotary operating member of the upper tension bolt  26 . In the same manner, a metal washer  32  and a brass washer  33  are arranged between the lower hoop  25  and a bolt head  27   a , which serves as a rotary operating member of the lower tension bolt  27 . Further, a rubber stopper  34  is arranged on a substantially intermediate part of the lower tension bolt  27  between the lower tension nut  29  and the lower hoop  25  to prevent the lower tension bolt  27  from falling off. 
     As shown in  FIG. 5 , an upper plate  35  is arranged on the top of the ring member  16  and a lower plate  36  is arranged on the bottom of the ring member  16 . Each leg  17  projects downward from the lower plate  36 . The upper plate  35 , the ring member  16 , the lower plate  36 , and the legs  17  are fastened together by a plurality of screws  37  inserted from above the upper plate  35  so that the legs  17  extend vertical relative to the floor. A resin cap  38  is attached to the lower end of each leg  17 . 
     (Frame  6 ) 
     The frame  6  will be now described in more detail. The frame  6  has the shape of a rectangular circuit, as shown in  FIGS. 3 ,  9 , and  10 . The frame  6  has a right side portion  6   a , a left side portion  6   b , a front side portion  6   c , and a rear side portion  6   d . The snare wires  7  are held in the region surrounded by these side portions. The opposite ends of the frame  6  extend diagonally from an upper outer edge to a lower inner edge. 
       FIG. 6  is a perspective view showing the frame  6  in a reversed state. Therefore, four directions (up, down, right, and left) of the frame  6  are as indicated in the drawing. The same applies to  FIGS. 7 and 8 . As shown in  FIG. 6 , a collective adjustment mechanism  39  is arranged at the right end of the frame  6  for collectively adjusting the tension applied to the snare wires  7 . An individual adjustment mechanism  40  for adjusting the tension applied to individual snare wires  7  is arranged at the left end of the frame  6 . 
     The collective adjustment mechanism  39  includes a collective adjustment piece  42 , having a lower portion provided with a plurality of parallel fitting grooves  41 , and a collective adjustment bolt  51 . The collective adjustment bolt  51 , which collectively adjusts the tension applied to the snare wires  7 , extends through a middle portion of the collective adjustment piece  42 . A rubber bolt tightening member  58  (see  FIG. 9 ) is mounted on the bolt  51 . 
     The individual adjustment mechanism  40  is provided with a plurality of (five in the present embodiment) first individual adjustment pieces  44  each having a fitting groove  43 , a plurality of (six in the present embodiment) second individual adjustment pieces  46  each having a fitting groove  45 , and screws  55  and screws  56  respectively associated with the first and second individual adjustment pieces  44  and  46 . The screws  55  and  56 , which serve as an operating means, adjust the tension applied to each of the snare wires  7  and respectively extend through the first and second individual adjustment pieces  44  and  46 . A rubber screw tightening member  59  is mounted on each of the screws  55  and  56  (see  FIG. 9 ). The fitting grooves  41 ,  43 , and  45  respectively have openings  41   a ,  43   a , and  45   a  extending downwards. 
     As shown in  FIG. 7 , each first individual adjustment piece  44  includes a rectangular parallelepiped first base  48  through which a screw hole  47  extends. A groove formation portion  49 , which is defined on the bottom of the base  48 , includes the fitting groove  43 , which is U-shaped. An extension  50  extends downward from the vicinity of the left end of the first base  48 . The groove formation portion  49  is located near the right end of the extension  50 . 
     As shown in  FIG. 8 , each second individual adjustment piece  46  includes a rectangular parallelepiped second base  53  through which a screw hole  52  extends. A groove formation portion  54 , which is defined on the bottom of the second base  53 , includes the fitting groove  45 , which is U-shaped. In contrast with the first individual adjustment piece  44 , the second individual adjustment piece  46  has no extension  50  provided on the second base  53 , and the second base  53  is smaller in size than the first base  48 . When the first and second individual adjustment pieces  44  and  46  are attached to the frame  6 , the second base  53  is arranged adjacent to the extension  50  of the first base  48  so that the fitting groove  43  of the first individual adjustment piece  44  is flush with and adjacent to the fitting groove  45  of the second individual adjustment piece  46  (see  FIG. 6 ). The fitting grooves  43  and the fitting grooves  45  are arranged alternately. In the present embodiment, a total of eleven parallel fitting grooves are arranged between the front and rear sides of the frame  6  in the same manner as the adjustment piece  42 . 
     A screw  55  (see  FIG. 6 ), which functions as an operating member for adjusting the tension applied to the associated snare wire  7 , is inserted in the screw hole  47  of the first individual adjustment piece  44  shown in  FIG. 7 . In the same manner, a screw  56 , which functions as an operating member for adjusting the tension applied to the associated snare wire  7 , is inserted in the screw hole  52  of the second individual adjustment piece  46  shown in  FIG. 8 . 
     Referring to  FIG. 6 , the ends of each snare wire  7  are press-fitted in a cylindrical metal sleeve  57 . The right end of the snare wire  7  is fitted in the associated fitting groove  41  of the adjustment piece  42 , while the left end of the snare wire  7  is fitted in the fitting groove  43  of the associated first individual adjustment piece  44  or the fitting groove  45  of the associated second individual adjustment piece  46 . Consequently, each snare wire  7  is held on the frame  6  by two cylindrical metal sleeves  57 . 
     The cylindrical metal sleeves  57  abut against abutment portions  60  defined in the associated fitting grooves  41 ,  43 , or  45  (see  FIG. 9 ) and are held by projections  71  formed at the ends of the groove formation portions  49  and  54  (i.e., the left ends in  FIGS. 7 and 8 ). This prevents the snare wires  7  from falling down. In the present invention, the abutment portions  60  correspond to lock portions. Further, the collective adjustment piece  42 , the first individual adjustment piece  44 , and the second individual adjustment piece  46  correspond to snare wire supports. 
     As shown in  FIG. 9 , the collective adjustment bolt  51  is fastened to the collective adjustment piece  42  in a state in which rotation of the collective adjustment piece  42  is restricted due to the engagement between the collective adjustment piece  42  and the frame  6 . Accordingly, if the collective adjustment bolt  51  is turned clockwise, the collective adjustment piece  42  moves rightward relative to the frame  6 . As a result, force is applied in a rightward direction (in a radially outward direction of the drum shell  2 ) to all the snare wires  7  fixed to the collective adjustment piece  42 . This increases the tension applied to the snare wires  7 . If the collective adjustment bolt  51  is turned counterclockwise, the tension applied to all the snare wires  7  decreases due to actions that occur in an opposite manner of the above-mentioned actions. 
     Further, the screws  55  are fastened to the associated first individual adjustment pieces  44  in a state in which rotation of the first individual adjustment pieces  44  is restricted due to the engagement between the first individual adjustment pieces  44  and the frame  6 . Accordingly, in the same manner as the collective adjustment bolt  51 , if any of the screws  55  is turned clockwise, the associated first individual adjustment piece  44  is moved leftward relative to the frame  6 . As a result, forced is applied in a leftward direction (in a radially outward direction of the drum shell  2 ) to the single snare wire  7  fixed to the first individual adjustment piece  44 . This increases the tension applied to the snare wire  7 . If the screw  55  is turned counterclockwise, the tension applied to the snare wire  7  is decreased due to actions that occur in an opposite manner of the above-mentioned actions. The actions of the screws  56  and the second individual adjustment pieces  46  occur in the same manner and will thus not be described in detail. 
     Further, the snare wires  7  may easily be removed from the frame  6  by loosening the associated screws  55  and  56  in the individual adjustment mechanism  40 . In this state, the cylindrical metal sleeves  57  at the opposite ends of the snare wires  7  are pulled out and separated from the abutment portions  60 . Then, the snare wires  7  are lifted out of the openings  41   a ,  43   a , and  45   a  of the fitting grooves  41 ,  43 , and  45  and removed from the frame  6 . 
     As shown in  FIG. 10 , a first engaged portion  61  is provided at the right end of the frame  6  facing towards the frame attachment mechanism  10  (see  FIG. 2 ), and a second engaged portion  62  is provided at the left end of the frame  6 . Bearings  63  and  64  are provided at the front and rear sides of the first engaged portion  61 . The bearings  63  and  64  support a first connection shaft  65 , which serves as a latched member. Bearings  66  and  67  are provided at the front and rear sides of the second engaged portion  62 . The bearings  66  and  67  support a second connection shaft  68  (locking shaft), which serves as a latched member. 
     As shown in  FIGS. 9 through 11 , a right pressing shaft  69  is provided in the right side portion  6   a  of the frame  6 . In the same manner, a left pressing shaft  70  is provided in the left side portion  6   b  of the frame  6 . The right and left pressing shafts  69  and  70  extend orthogonally to the snare wires  7  and extend through the front and rear side portions  6   c  and  6   d . As shown in  FIG. 9 , the right and left pressing shafts  69  and  70  function as adjustment members for adjusting the heights of the snare wires  7  such that the snare wires  7  uniformly abut against the lower head  4 . 
     (Damper  8 ) 
     As shown in  FIG. 13 , each damper  8  includes a slide member  82  which bridges between the front side portion  6   c  and rear side portion  6   d  of the frame  6 . The damper  8  further includes a thin rectangular parallelepiped damping plate  83 , a felt pad  84 , a lower operating screw  85 , and a rear operating screw  86 . The slide member  82  includes a projection  87  having a substantially U-shaped cross-section and formed on the front inner wall. The projection  87  is engaged with a groove  88  formed in the front side portion  6   c  of the frame  6 . The slide member  82  has a rear side portion  90  with an inner surface slightly spaced from the rear side portion  6   d  of the frame  6 . The rear operating screw  86  is inserted in the slide member  82  from the rear side so that the front end of the rear operating screw  86  abuts against a groove  89  formed in the rear side portion  6   d  of the frame  6 . This fixes the damper  8  to the frame  6 . Further, a hole  91  is formed in the top of the rear side portion  90  of the slide member  82 . A rubber tightening member  92  is provided in the hole  91  to prevent the loosening of the rear operating screw  86 . 
     The rear operating screw  86  is tightened so that the front end of the rear operating screw  86  comes into contact with the frame  6  and is loosened to separate the front end of the rear operating screw  86  from the frame  6 . When the front end of the screw  86  is separated from the frame  6 , sliding of the damper  8  in the longitudinal direction of the frame  6  is enabled. 
     The pad  84  is bonded to the damping plate  83 . The damping plate  83  is integrated with the slide member  82  by the lower operating screw  85 , which extends through the slide member  82  and plate  83 . Further, a rubber tightening member  93  is fixed to the lower surface of the slide member  82  to prevent loosening of the lower operating screw  85 . 
     The lower operating screw  85  is tightened and loosened to vertically move the sound reduction plate  83  so that the pad  84  contacts or moves away from the snare wires  7 . The pad  84  contacts the snare wires  7  to suppress resonance of the snare wires  7  and mute the noise of the snare wires  7 . 
     (Frame Attachment Mechanism  10 ) 
     The operating mechanism  11  and the fixing mechanism  12  of the frame attachment mechanism  10  will now be described. 
     The operating mechanism  11  shown in  FIG. 2  is connected to the first engaged portion  61  of the frame  6  that includes the first connection shaft  65  to attach the frame  6  to the drum shell  2 . A base plate  101  separates the operating mechanism  11  from the drum shell  2  by a predetermined distance. A fixing member  102  fixing the upper part of the base plate  101  is fixed to the reinforcing ring  21  with a screw (not shown). In the same manner, a fixing member  103  fixes the lower part of the base plate  101  to the ring member  16  with a screw (not shown). 
       FIG. 14  shows the operation lever  14  in a state in which the operation lever  14  is located at the lowermost position of its pivotal range.  FIG. 15  shows the operation lever  14  in a state in which the operation lever  14  is located at the uppermost portion of its pivotal range. As shown in  FIGS. 14 and 15 , a bracket  104  having a U-shaped plane cross-section is fixed to the base plate  101  by means of two screws  105  and  106  with its attachment portion  1   04 a in contact with the base plate  101 . 
     A slide member  107  having a U-shaped plane cross-section covers the bracket  104 . The slide member  107  has an intermediate portion  107   a  spaced from and facing towards the base plate  101 . A rubber stopper  142  for the operation lever  14  (see  FIG. 15 ) is attached to the intermediate portion  107   a  of the slide member  107 . 
     As shown in  FIG. 17 , two elongated holes  108  and  109  extend through the upper part and the lower part of the two side walls of the slide member  107 . As shown in  FIG. 16 , two elongated holes  94  extend through the upper part of the bracket  104  in the same manner. A coupling shaft  110  is inserted through the right and left elongated holes  108  of the slide member  107  and the right and left elongated holes  94  of the bracket  104 . Each end of the coupling shaft  110  is coupled with an associated link  114  by a screw. The coupling shaft  110  has a substantially square cross-section (see  FIG. 17 ) so that the coupling shaft  110  does not rotate relative to the elongated hole  94 . Further, the links  114  are rotatable with respect to the coupling shaft  110 . A rubber washer  95  is attached to the upper surface of the coupling shaft  110 . 
     A support shaft  111  is inserted through the two elongated holes  109  of the slide member  107  to extend through a lower portion  112  of the bracket  104  at the outer side of the elongated holes  109 . The basal end of the operation lever  14  is connected to opposite ends of the support shaft  111  by a pair of screws  14   a  so as to enable relative pivoting between the operation lever  14  and the support shaft  111 . Two bushings  96  are attached to the support shaft  111 . Each bushing  96  is in contact with the lower portion  112  of the bracket  104  and the wall of the associated elongated hole  109  of the slide member  107 . 
     The lower ends of the two links  114  are pivotally coupled to the operation lever  14  at a position separated from the basal end of the operation lever  14  by a predetermined distance. As described above, the upper end of each link  114  is pivotally coupled to the coupling shaft  110 . Accordingly, when the operation lever  14  is pivoted, the motion of the operation lever  14  is transferred to the coupling shaft  110  by the links  114 . Thus, the coupling shaft  110  slides along the walls of the elongated holes  94  in the bracket  104 . As the coupling shaft  110  slides, the slide member  107 , which is connected to the coupling shaft  110  by a fine adjustment bolt  126 , slides vertically within a range corresponding to the length of the elongated holes  109  and independently from the bracket  104  with the support shaft  111  functioning as a guide. 
     Additionally, the upper end of a curved arm  115  is pivotally coupled to the lower end of the slide member  107 . An operation shaft  116  is inserted through the lower end of the arm  115  with the two ends of the operation shaft  116  projecting out of the arm  115 . 
     As shown in  FIG. 15 , a mounting portion  118  having a shaft hole is defined on the lower surface of the lower plate  36  so as to extend downwards. A shaft  119  is inserted through the shaft hole. The basal end of a coupling arm  120  is pivotally coupled to the shaft  119 . The coupling arm  120  has a bifurcated distal end  121 . The distal end  121  of the coupling arm  120  supports the lower end of the arm  115  from opposite sides. In this state, the coupling arm  120  is pivotally connected to the arm  115  by the operation shaft  116 . 
     The upper end of a latching member  122  having a hook-shaped distal end  123  is pivotally connected to the operation shaft  116 . As shown in  FIGS. 14 and 18 , the distal end  123  is hooked to the first connection shaft  65  of the frame  6 . Further, an operating portion  124  is provided on a side of the latching member  122  to manipulate the latching member  122  with a finger. 
     A spring  125  is wound around the operation shaft  116  with one end being hooked to the coupling arm  120  and the other end hooked to the latching member  122 . Thus, the spring  125  urges the latching member  122  to pivot counterclockwise as viewed in  FIG. 14  in a radially outward direction of the drum shell  2 . As shown in  FIG. 15 , the latching member  122  has a notch  140 , which abuts against a stopper  141  projecting from the distal end  121  of the coupling arm  120  to restrict further counterclockwise pivoting of the latching member  122 . The latching member  122  having the operating portion  124 , the operation shaft  116 , and the spring  125  form an engagement portion  128 . 
     The fine adjustment bolt  126  of the operating mechanism  11  finely adjusts the position of the frame  6  when the snare wires  7  are in contact with the lower head  4 . The fine adjustment bolt  126  has a head  126   a  located above the bracket  104 . More specifically, a support member  127  is fixed by two screws  129  and  130  in the slide member  107 , which extends along the outer wall of the drum shell  2 . The fine adjustment bolt  126  extends through the support member  127  and the coupling shaft  110 . The fine adjustment bolt  126  is provided with a snap ring  117  engaging the lower portion of the coupling shaft  110 . The coupling shaft  110  is coupled to the bolt  126  in a state in which the coupling shaft  110  is held between the snap ring  117  and a stepped portion of the fine adjustment bolt  126 . Accordingly, the fine adjustment bolt  126  is rotatably inserted through the coupling shaft  110  and fastened with the support member  127 . The height of the fine adjustment bolt  126  and the coupling shaft  110  relative to the support member  127 , that is, the distance between the coupling shaft  110  and the support member  127  is adjusted by rotating the fine adjustment bolt  126 . This adjusts the height of the slide member  107  relative to the coupling shaft  110 . For example, if the fine adjustment bolt  126  is rotated clockwise to decrease the distance between the coupling shaft  110  and the support member  127 , the slide member  107  is lifted by a distance corresponding to the number of rotations of the fine adjustment bolt  126 . Consequently, the latching member  122  is also lifted to raise the frame  6 . 
     In this state, the relative position between the coupling shaft  110  and the slide member  107  changes. As shown in  FIG. 17 , however, since margins are provided at the upper and lower sides of the elongated hole  108 , the relative position changes within the range corresponding to the margins. 
     The fixing mechanism  12  will now be described with reference to  FIG. 14 . The fixing mechanism  12  is a mechanism which is coupled to the engaged portion  62 , which includes the second connection shaft  68  of the frame  6 , to fix the frame  6  to the drum shell  2 . As shown in  FIG. 14 , a joining member  132  having an L-shaped cross section is provided on the lower surface of the lower plate  36 . The joining member  132  is provided with a latching member  134  having a C-shaped distal end  133 . The second connection shaft  68  of the frame  6  is latched by the distal end  133 . 
     In the same manner as the fine adjustment bolt  126  of the operating mechanism  11 , the fixing mechanism  12  also has a fine adjustment bolt  135  for finely adjusting the position of the frame  6  when the snare wires  7  are in contact with the lower head  4 . The fine adjustment bolt  135  extends through the upper plate  35  and the lower plate  36  and is fastened to the latching member  134 . A sleeve  136  is arranged between the fine adjustment bolt  135  and the upper plate  35 . An adjusting spring  137  is arranged around the fine adjustment bolt  135  below the lower plate  36 . Accordingly, the fastening amount of the fine adjustment bolt  135  relative to the latching member  134  is adjusted by rotating the fine adjustment bolt  135 . This finely adjusts the distance between the lower plate  36  and the latching member  134 . 
     Covers  138  and  139  cover the latching members  122  and  134  of the operating mechanism  11  and the fixing mechanism  12 , respectively. The cover  138  covers the operating portion  124  of the latching member  122  to prevent the latching member  122  from being released from the first connection shaft  65  when the operating portion  124  is accidentally pushed. 
     With regard to the drum  1  having the above snare wire unit, the procedure for attachment and detachment of the frame  6  on the lower head  4  and the operation of the snare wire unit will now be described. 
     The attachment of the frame  6  to the lower head  4  will first be described with reference to  FIG. 14 . In a state in which the operation lever  14  is located at the lowermost position as shown by the broken lines in  FIG. 14 , the second connection shaft  68  of the frame  6  is latched at the distal end  133  of the latching member  134  of the fixing mechanism  12 . In this state, the frame  6  is pivotal about the second connection shaft  68  towards and away from the lower head  4 . The snare wires  7  are separated from the lower head  4 . 
     In this state, the frame  6  is moved toward the lower head  4  so that the first connection shaft  65  of the frame  6  approaches the latching member  122  of the operating mechanism  11 . The first connection shaft  65  is then latched at the distal end  123  of the latching member  122 . When the first connection shaft  65  comes into contact with the distal end  123  from the outer side (right side in  FIG. 14 ) of the distal end  123 , the latching member  122  pivots slightly clockwise against the force of the spring  125 . Then, when the first connection shaft  65  is fitted in the distal end  123 , the latching member  122  is pivoted counterclockwise by the force of the spring  125  and the distal end  123  is hooked to the first connection shaft  65  and locked in such a state. 
     At this stage, as shown in  FIG. 14 , the frame  6  is fixed to the drum  1  but the snare wires  7  are still separated from the lower head  4 . If the drum  1  is to be played without using the resonance of the snare wires  7 , the drum  1  is used in this state, or in a state in which the snare wires  7  are inactive. 
     Then, the operation lever  14  is lifted in a state in which the snare wires  7  are separated from the lower head  4 . This pushes the coupling shaft  110  upward with the link  114 . The upward movement of the coupling shaft  110  is transferred to the slide member  107 . This lifts the slide member  107 . As the slide member  107  moves upward, the arm  115 , the coupling arm  120 , and the operation shaft  116  lift the latching member  122 . The upward movement of the latching member  122  causes the frame  6  to move toward the lower head  4  until the snare wires  7  come into contact with the lower head  4 . 
     When the coupling point P of the link mechanism formed by the operation lever  14  and the link  114  moves toward the drum shell  2  beyond a dead point lying on a hypothetic line extending through the axes of the support shaft  111  and the coupling shaft  110 , a reaction force of the force pushing the frame  6  toward the lower head  4 , that is, a force pulling the slide member  107  downwards, is converted to a force that rotates the operation lever  14  counterclockwise in  FIGS. 14 and 15 . Due to the force, the operation lever  14  abuts against the rubber stopper  142  on the slide member  107  (see  FIG. 15 ) and is locked in a state in which the frame  6  is located near the lower head  4 . 
     To increase the force applied to the frame  6  in the locked state, the rubber washer  95  (see  FIG. 16 ) is arranged on the upper surface of the coupling shaft  110  so that a larger downward force is applied to the slide member  107  at a position beyond the dead point. A reaction force generated when the rubber washer  95  is deformed by the wall of the elongated hole  94  of the bracket  104  functions as a force downwardly pushing the coupling shaft  110  and the slide member  107 , which is coupled to the coupling shaft  110 . This increases the force acting on the frame  6  in the locked state. 
     When using the resonance of the snare wires  7  to play the drum  1 , the drum  1  is played in this state, that is, in a state in which the snare wires  7  are active. 
     In this manner, the simple operation of latching the latching members  122  and  134  to the corresponding first and second connection shafts  65  and  68 , which are arranged on opposite ends of the frame  6 , enables the engaged portions  61  and  62  of the frame  6  to be engaged with the frame attachment mechanism  10 . In other words, the frame  6  is easily attached to the lower head  4  by just hooking the opposite ends of the frame  6  to the drum shell one after the other. 
     To detach the frame  6  from the lower head  4 , the operation lever  14  is moved downward so that the snare wires  7  become inactive as shown in the state of  FIG. 14 . The operating portion  124  of the latching member  122  is then pressed with a finger towards the drum shell  2 . As a result, the latching member  122  is pivoted around the operation shaft  116  towards the drum shell  2 , and the distal end  123  of the latching member  122  is separated from the first connection shaft  65 . This releases the latching member  122  from the first connection shaft  65 . The second connection shaft  68  is then pulled out from the distal end  133  of the latching member  134  in a radially outward direction of the drum shell  2 . This releases the latching member  134  from the second connection shaft  68 . In the above embodiment, the frame  6  is attached and detached when the snare wires  7  are in an inactive state. However, the attachment and detachment of the frame  6  may also be performed when the snare wires  7  are in an active state. 
     As described above, the detachment of the frame  6  from the lower head  4  is also performed through an extremely simple operation. The operating portion  124  is first pressed to remove the frame  6  from the side closer to the operating mechanism  11  and then the side closer to the fixing mechanism  12 . Accordingly, the frame  6  is attached to and detached from the lower head  4  in an extremely simple manner. 
     The above embodiment has the advantages described below. 
     (1) In the above embodiment, the first and second connection shafts  65  and  68  are arranged at the two ends of the frame  6 , and the latching members  122  and  134  shaped to enable engagement with the shafts  65  and  68  are arranged in the frame attachment mechanism  10 . Accordingly, the engaged portions  61  and  62  at the two ends of the frame  6  are easily engaged with the frame attachment mechanism  10  by a simple operation of latching the latching members  122  and  134  to the shafts  65  and  68 . As a result, the attachment and detachment of the frame  6  is easily performed and thus the task is simplified. 
     (2) The latched members (first and second connection shafts  65  and  68 ) engaged with the frame attachment mechanism  10  are shaft-shaped. This simplifies the structure for hooking or fitting the latching members  122  and  134  at the side of the frame attachment mechanism  10 . 
     (3) The operating mechanism  11  of the above embodiment is arranged on the base plate  101 , which is located between the reinforcing ring  21  and the ring member  16  and separated from the drum shell  2  by a predetermined distance. Therefore, the load produced when the operation lever  14  is manipulated or the frame  6  is attached is not directly applied from the operating mechanism  11  to the drum shell  2 . Therefore, the drum shell  2  is not deformed by such loading, and the sound of the drum  1  is not affected by such deformation. 
     (4) In the above embodiment, the latching member  122  of the operating mechanism  11  is constantly urged by the spring  125  in a radially outward direction of the drum shell  2 . Therefore, engagement of the first connection shaft  65  and the latching member  122  against the urging force latches the first connection shaft  65  and the latching member  122  to each other. 
     (5) In the embodiment above, the snare wires  7  are held by the frame  6 , and the collective adjustment mechanism  39  and the individual adjustment mechanism  40  for adjusting the tension of the snare wires  7  are arranged on the frame  6  so that they are completely independent from the drum shell  2  of the drum  1 . Accordingly, the tension of the snare wires  7  does not vary before or after detachment of the frame  6 . Thus, further tension adjustment is not required when the frame  6  is re-attached to the drum  1  after being detached from the frame  6 . 
     (6) Further, the tension of the snare wires  7  is received by the frame  6 . Thus, the tension is not applied to the drum shell  2  of the drum  1  or the operation lever  14 . Accordingly, this strength is not required to operate the operation lever  14 . Further, deformation of the drum shell  2  that would affect the sound of the drum  1  does not occur. 
     (7) In the above embodiment, the latching member  122  has two hook-shaped distal ends  123 , as shown in  FIG. 18 , so that the first connection shaft  65  is latched at two locations. Therefore, the first connection shaft  65  and the latching member  122  are engaged with each other more stably in comparison to when the first connection shaft is latched at one location. 
     (8) In the above embodiment, the snare wires  7  are fitted in the fitting grooves  41 ,  43 , and  45  as shown in  FIGS. 7 through 9 , and the cylindrical metal sleeves  57  at the ends of the snare wires  7  abut against the abutment portions  60  and are locked by the projections  71 . The ends of the individual snare wires  7  are fitted in the fitting grooves  41 ,  43 , and  45  independently from each other through the openings  41   a ,  43   a , and  45   a . Therefore, the attachment and detachment of each snare wire  7  is easily performed. This enables the number of the snare wires  7  to be decreased and then returned to the original number. 
     (9) In the above embodiment, the frame  6  is provided with the two dampers  8 . Thus, the resonance of the snare wires  7  may easily be adjusted whenever the drum  1  is played. Further, the dampers  8  are each designed such that the pressure of the pad  84  applied to the snare wires  7  is adjusted by tightening or loosening the lower operating screw  85 . Therefore, the level of resonance may be adjusted in accordance with the drummer&#39;s preference. Further, the dampers  8  may be moved in the longitudinal direction of the frame  6  by loosening the rear operating screw  86 . Therefore, any desired tone can be obtained by adjusting the position of the damper  8 . 
     (10) In the above embodiment, as shown in  FIG. 10 , the pressing shafts  69  and  70  are arranged in the right side portion  6   a  and the left side portion  6   b  of the frame  6 , respectively. Therefore, the height of the snare wires  7  are adjusted to contact the head surface in a uniform manner. 
     (11) In the above embodiment, the cover  138  covers the operating portion  124  of the latching member  122 . This prevents the frame  6  from being detached from the drum  1  when the latching member  122  is accidentally released from the first connection shaft  65 . 
     (12) In the above embodiment, the switching device  13 , which includes the operation lever  14 , is arranged on the base plate  101  between the reinforcing ring  21  and the ring member  16 . Accordingly, the operation lever  14  is arranged on the upper part of the drum  1 . Thus, the operation lever  14  is located at a position where it can easily be operated during marching. 
     It should be apparent to those skilled in the art that the present invention may be embodied in many other specific forms without departing from the spirit or scope of the invention. Particularly, it should be understood that the present invention may be embodied in the following forms. 
     In the above embodiment, the first connection shaft  65  and the distal end of the latching member  122  are latched together and locked by the urging force of the spring when attaching the frame  6  to the drum  1 . However, the frame  6  may be manually attached by pressing the operating portion  124  of the latching member  122  with a finger as when detaching the frame  6  in a state in which the distal end  123  is separated from the first connection shaft  65 . 
     The snare wires  7  do not necessarily have to be formed from stringing and may be formed from metal wire or coil spring. 
     The latched members (the first connection shaft  65  and the second connection shaft  68 ) arranged at the ends of the frame  6  and the latching members  122  and  134  do not necessarily have to be shaft-shaped or hook-shaped. It is only required that the latching members and the latched members are shaped such that they can be latched with each other. Thus, the latched and latching members may be modified. For example, the latched and latching members may both be hook-shaped. Alternatively, the latched members may be hook-shaped, and the latching member may be shaft-shaped. 
     In the above embodiment, the latching member  122  has two hook-shaped distal ends  123  so as to hook the first connection shaft  65  at two locations. However, the latching member  122  may have only one distal end  123 . 
     The covers  138  and  139  in the above embodiment may be omitted. 
     The present examples and embodiments are to be considered as illustrative and not restrictive, and the invention is not to be limited to the details given herein, but may be modified within the scope and equivalence of the appended claims.