Abstract:
A drum pedal assembly is constructed with a beater assembly having a base plate adapted to sit on the floor and having an outer end adapted to be juxtaposed with a drum. Upright posts are mounted on the base plate and a split shaft is mounted to an upright posts. The split shaft has a pair of coaxial shaft parts having outer ends journaled in bearings housed in the upright posts and axially juxtaposed inner ends journaled in a central support member. A drum beater is mounted on each of the coaxial shafts. The beater is driven by a pair of pedal assemblies, each provided with a pedal pivoted mounted on a separate base plate and a pair of posts having upper and lower ends mounted on the base plate. The post upper ends house bearings and a shaft is rotatably mounted in the bearings. A linkage is mounted on the pedal and is secured to a sprocket mounted on the shaft for rotation of the shaft on depression of the pedal and connector assemblies connect the pedal shaft with the beater split shaft to transmit torque to the split shaft driving the drum beater.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   There are no related applications. 
   TECHNICAL FIELD OF THE INVENTION 
   The present invention relates generally to drum pedals, and more particularly to a foot operated bilateral drum pedal of the type used to play floor standing bass drums. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates generally to drum pedals. In particular, the present invention relates to a dual foot operated drum pedal with pedal assemblies located on opposite sides of the drum beater assembly, each pedal assembly selectively operating a drum beater independently of the other pedal assembly. 
   2. Discussion of Background 
   In most contemporary musical styles ranging from classical through to jazz, pop and rock, bass drums are typically played using a foot operated pedal arrangement. A typical arrangement of this type includes a base or frame designed to rest on the flood and adapted for connection to the drum, so as to maintain the pedal and the drum in predetermined spatial relationship. The base is adapted to support a beater shaft for rotation about an horizontal axis. The beater shaft supports an elongate beater stem and a beater head is attached to the remote end of the stem. Some form of drive mechanism extends between the foot pedal and the beater shaft, such that depression of the foot pedal by the player effects rotation of the beater shaft. This in turn drives the beater head forward in an arc defined by the beater stem, so as to hit the diaphragm or skin of the drum. This arrangement leaves the drummer&#39;s hands free to play other drums and symbols. 
   Early arrangements of this type only made use of a single pedal activating a single beater. This limited the speed and complexity of rhythms that could be played on the drum, while leaving the player&#39;s other foot under utilized. A typical single drum beater using a pivoting pedal which drives a chain linkage connected to a beater shaft sprocket is shown by U.S. Pat. No. 5,317,946 issued to Hoshino on Jun. 7, 1994. As a result of these limitations, so-called “twin pedal” arrangements were developed, whereby both of the player&#39;s feet could be used to operate two pedals, and hence two beaters, independently. 
   While these twin pedal arrangements allowed more complex bass drum rhythms to be played more easily, such structures are subject to a number of inherent limitations. The first of these arises because the ideal strike zone or “sweet spot” on the drum skin is relatively small and striking the skin outside of this zone produces an inferior quality of sound. Most twin pedal devices require the beaters to be positioned apart from one another, to the extent that with the assembly centrally positioned, the beaters make contact with the drum skin on either side of the optimum strike zone, rather than hitting it directly. Furthermore the beaters are generally operated by foot pedals which require both heel and toe control from each foot. 
   In an attempt to address this problem, some twin pedal assemblies have positioned the beaters as closely together as possible. In many cases, however, this has necessitated spacing the foot pedals similarly closely together, which severely compromises the ergonomics from the player&#39;s perspective. 
   Other known twin pedal arrangements have attempted to address this difficulty, using relatively complex drive mechanisms, extended linkages and interconnecting universal joints, so as to space the pedals outwardly from the beaters. A limitation with arrangements of this type, however, is that these more complex linkage arrangements introduce flexibility and friction into the drive mechanism, both of which absorb power, reduce efficiency and compromise the sensitivity and “feel” of the system as experienced by the player. A common complaint from players in this context is that such systems feel “remote” or “disconnected”. Systems of this type are also susceptible to rapid wear and failure due to the relatively high stresses imposed on the key linkages and supporting frame elements. 
   The modern drummer frequently relies on both his hands and feet to play a variety of different drums and other percussion instruments requiring the drummer to quickly switch back and forth from instrument to instrument. It is to the drummer&#39;s advantage to be able to spread his workload over as many limbs and muscle groups as possible to prolong his or her endurance and resist fatigue and injury and to be able to produce as many diverse combinations of sounds as possible. 
   A number of different foot-pedal actuated drum-beaters have been devised, each offering some advantages to the drummer. These prior art devices include those described in the following patents: U.S. Pat. No. 1,508,390 issued to Gladstone et al. on Sep. 16, 1924; U.S. Pat. No. 2,484,302 issued to Laverents on Oct. 11, 1949; U.S. Pat. No. 3,677,128 issued to Simpson on Jul. 18, 1972; U.S. Pat. No. 3,988,957 issued to Escamilla on Nov. 2, 1976; and U.S. Pat. No. 4,945,803 issued to Norwood on Aug. 7, 1990. 
   The &#39;390 patent discloses a single double-acting mallet actuated by the forward depression of a foot pedal. The &#39;302 patent uses a pair of beaters that alternately strike a single drumhead, actuated by the heel-to-toe rocking motion of the drum pedal. The &#39;128 patent discloses a pair of mallets, each striking its own drum, actuatable respectively by the toe and heel of a single split pedal. The &#39;957 patent shows a drum pedal assembly in which a split foot pedal operates a pair of drumsticks against a single drum head. The &#39;803 patent similarly shows a pair of mallets that alternately strike a single drum head upon the forward depression of a single toe pedal. 
   While these devices have solved some problems, they suffer from various disadvantages. Some require two separate drums, which take up space that could be used for different percussion instruments. Others are limited in that the pair of mallets disclosed may only operate alternately and not independently of each other. Still others employ rough mechanical means that generate an unwelcome level of noise. 
   Despite the above advances, there is still a need for a foot-pedal actuated drum beater system that gives the drummer a greater variety of musical options while optimizing instrument space and minimizing muscle fatigue on the part of the drummer. 
   Hence, there is a need for an improved foot pedal device for playing a drum. The present invention satisfies this need. 
   SUMMARY OF THE INVENTION 
   A dual drum pedal assembly having a beater assembly with a base plate adapted to sit on the floor and having an outer end adapted to be juxtaposed with a drum. Upright posts are mounted on the base plate with the upright posts being interconnected and support by cross members. A split shaft beater shaft is mounted to the upper portion of each upright support. The split shaft has a pair of coaxial shafts having one end journaled in a central support member which is mounted to one of the cross members and an opposite end mounted to an upright support with each coaxial shaft being able to independently rotate with respect to the other coaxial shaft. A plurality of drum beaters are mounted on the coaxial shafts with each drum beater comprising a shaft mount adjustably mounted on one of the coaxial shafts, a beater arm mounted in the shaft mount and a beater head secured to distal end of the beater arm. Pedal assemblies located on each side of the beater assembly are constructed with a pedal pivotally mounted on a separate base plate, the base plate being provided with a pair of posts having lower ends mounted on the base plate with bearings races mounted on the post upper ends and a shaft rotatably mounted in the bearing races. A flexible linkage links the pedal to a sprocket mounted on the shaft for rotation of the shaft by depression of the pedal. The pedal shaft of each pedal assembly is connected to the beater assembly by a connector assembly which connects a pedal shaft with one of the split beater shafts so that action by the pedal rotates the pedal shaft, the respective connector assembly and associated beater split shaft causing a beater mounted on the split shaft to strike an adjacent drum. 
   It is an object of the invention to provide a bilateral symmetrical design creating a pedal unit where both pedals feel identical to the drummer. 
   It is another object of the invention to provide quad drive springs to the beater split shafts for increased response and sensitivity. 
   It is still another object of the invention to provide a center mounting hoop clamp on the beater plate which eliminates all lateral torque on the bass drum hoop. 
   It is yet another object of the invention to object to offset the center mounting hoop clamp to provide easy user access. 
   It is another object to the invention to create an ergonomic drum centering bi-lateral drum pedal. 
   It is still another object of the invention to create spring loaded plate levelers and anti skid pads on both the pedal base plates and center beater. 
   It is yet another object of the invention to have fully adjustable concentric double chain drives which can be adjusted laterally. 
   It is still another object of the invention to provide independent adjustable beater holders with lateral adjustment of each beater. 
   It is yet another object of the invention to have beater heads with opposite end drum striking surfaces of different hardness. 
   It is still another object of the invention to provide a free standing pedestal design allowing for more downward travel of the pedal. 
   These and other objects, advantages, and novel features of the present invention will become apparent when considered with the teachings contained in the detailed disclosure along with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of the dual drum pedal invention; 
       FIG. 2  is an enlarged view of the drum beater assembly and connector assemblies partially shown in phantom as shown in  FIG. 1 ; 
       FIG. 3  is a top plan view of the drum beater assembly shown in  FIG. 2 ; 
       FIG. 4  is a bottom plan view of the base plate of the drum beater assembly shown in  FIG. 2 ; 
       FIG. 5  is a side elevational view in partial cross sectional view taken along line  5 ′  5 ′ shown in  FIG. 3 . 
       FIG. 6  is a side elevational view of the drum beater assembly shown in  FIG. 2  with the keying mechanism shown in exploded view; and 
       FIG. 7  is an enlarged perspective view of a connector assembly shown in  FIG. 2  with the connector joint covering partially removed; 
       FIG. 8  is an enlarged rear elevational view of a pedal assembly shown in  FIG. 1 ; 
       FIG. 9  is a bottom plan view of the pedal assembly base plate shown in  FIG. 1 ; and 
       FIG. 10  is an enlarged perspective view of the beater rotatable clamping mount. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The preferred embodiment and best mode of the invention is shown in  FIGS. 1 through 10 . 
   The invention is directed toward a dual drum pedal assembly  10  having a beater assembly  20  which is activated and operated by pedal assemblies  100  and  101  positioned on opposite sides of the beater assembly  20 . The action of the pedal assemblies  100  and  101  is transmitted to a split shaft  36 / 37  of the beater assembly  20  by intermediate connector assemblies  160  and  161 . 
   The beater assembly  20 , as more clearly shown in  FIGS. 2-4 , is formed with a solid base plate  22  upon which an upright frame is mounted by screws  25 . The bottom of the base plate  22  is provided with a plurality of skid strips  23  which keep the beater assembly  20  from moving when the beaters are driven via the action of pedal assemblies to strike the drum. The frame has two upright standards  26  and  28  having respective support feet  27  and  29  which are secured to the solid base plate  22  by screws  25  or other securing means. Each of the support feet  27  and  29  has a leveling assembly  31  moveably mounted thereto for leveling the base plate  22  on uneven surfaces. A leveling support bar  33  is secured to the top of the base plate  22  by screws  34 . Two leveling assemblies  35  are mounted in the support bar  33 . Each of the leveling assemblies  31  and  35  as more clearly seen in  FIGS. 2 ,  3  and  5  are constructed with a threaded shank  37  which is screwed into a threaded bore formed in the respective support feet  27  and  29  and the support bar  33 . The shank  37  has a knurled head  38  which allows the screw shank  37  to be screwed downward so that the distal tip  39  of the screw (see  FIG. 4 ) raises or lowers that portion of the base plate  22  adjacent the respective leveling assembly. A spring  40  engages the under surface of the head  38  and the top surface of the support foot  27 / 29  or the top surface of the leveling support bar  33  to bias the screw outward away from the base plate  22 . 
   The upright standards  26  and  28  of the frame are spaced and supported by a lower cross support bar  30  and an upper cross support bar  32  which have their ends mounted to the upright standards  26  and  28  by screws. The screws are threaded in respective bores cut into the sides of the standards with the screws being threaded into the ends of the respective cross support bars  30  and  32 . The upright standards  26  and  28  have a throughgoing bore drilled therethrough with an outer countersunk portion which allows the screw head to be inserted into the countersunk portion so that the screw head does not extend outside the exterior surface of the standard. A split shaft  36 / 37  is rotatably mounted in yokes or bearing housing  26 ( a ) and  28 ( a ) formed on the distal end of each of the standards  26  and  28  and a center bearing shaft support member  41  which is secured to upper cross support bar  32 . As seen in  FIG. 5  the upper portion of support member  41  has a throughgoing bore drilled there through which holds two coaxial bearing sleeves  42 , one for shaft  36  and the other for shaft  37 . Outer bearing sleeves  38  are coaxially mounted in respective yokes or bearing housings  26 ( a ) and  28 ( a ) and the coaxially aligned shafts  36 / 37  have one end mounted in the bearing sleeve  38  on one upright standard and the other end mounted in a bearing sleeve  42  mounted in the center support member  41 . The bearing sleeve  42  is split into two sections so that each side rotates independently of the other side and shaft  36  can rotate independently of shaft  37 . Each of shafts  36  and  37  are tensioned on their distal end extending outside the respective standard by a spring assembly  43  to return to a set position upon release of the respective transmitted pedal torque. The spring assembly  43  as most clearly seen in  FIG. 6  which is the same on the beater assembly  20  and each pedal assembly  100  and  101 , is mounted an eye member  44  integrally formed on the bottom section of standards  26  and  28  and extends outward therefrom and transverse thereto. Each eye member  44  is positioned above the foot  27 / 29  of each of the standards  26 / 28  and defines a throughgoing bore oriented perpendicular to the horizontal plane of the base plate  22 . A serrated shaft mount member  46  as seen in  FIG. 33  is mounted to shaft extension portions  36 ( a ) and  37 ( a ) of each of the shafts  36  and  37  by a set screw. Each shaft extension portion  36 ( a ) and  37 ( a ) is formed with a flat locking portion  36 ( b ) and  37 ( b ) as seen in  FIG. 6 . 
   The spring assembly  43  is constructed with an adjustable threaded eye anchor mechanism  52 , a coil spring  54  having one end  55  looped to fit into the eye  53  of the eye anchor mechanism  52  with the other spring end  56  mounted through an aperture  58  cut into a pivotal shaft clamp coupler member  57 . The pivotal shaft clamp coupler member  57  defines a throughgoing bore  59  which holds a pivot arm  60  of an adjustable clamp member  62 . The pivot arm  60  rotates within bore  59 . The adjustable clamp member  62  has two jaws  63  which can be tightened by a screw  64  around the serrated shaft mount member  46  thus allowing the beaters shafts to be selectively positioned to a desired orientation. The spring  54  returns the shaft and the mounted beater to a predetermined position after the torque generated by the pedal assembly is released. 
   Two concentric beater head mounts  66  and  68  (see  FIGS. 6 and 10 ) are respectively fixedly mounted on the shafts  36  and  37 . Each drive head is constructed with a stepped mounting collar  69  fixed to the shaft  36 / 37  by set screws and an adjustable clamping mount  70  rotatable on the stepped cylindrical collar  69 . The clamping mount body  70  can be loosened from engagement with collar  69  with tightening screw  71  to rotatable clamping mount  70  to the desired position on the collar which is mounted to the shaft. The clamping mount body  70  defines a bore  73  which is adapted to hold a shaft  72  of a drum beater. The drum beater is constructed with a shaft  72  and a beater head  74  having a hard end portion  75  and a soft end portion  76  allowing the drummer to change the sound of the beat by positioning a specific head side to strike the drum. A cylindrical stop member  77  is mounted on each of the shafts  72  to allow the shaft to be inserted into the clamping mount bore  73  a predetermined distance. Each cylindrical stop member  77  has a throughgoing bore allowing a screw fastener to be inserted therein to engage the beater shaft  72  holding the cylindrical stop member in a fixed position on the shaft. The beater shaft  72  is held in fixed position within the bore  71  by threaded fasteners  77  as shown in  FIG. 3 . 
   A drum hoop clamp mechanism  80  as seen in  FIGS. 2 ,  3 ,  5  and  6  is secured to the top of the base plate  22 . The hoop clamp mechanism  80  is a center mounting hoop clamp which eliminates all lateral torque on the bass drum hoop. The hoop clamp mechanism  80  is constructed with a base member  81  secured to the base plate  22  by screws. The base member  81  forms a yoke having arms with a well  83  formed in the bottom of the U formed by the yoke to hold spring  84 . The hoop locking clamp bar  85  which engages the drum rim is urged upward by spring  84  mounted in the base of the yoke which engages the bottom surface of the locking clamp bar  85  and is seated in well  87  formed in the bottom surface of locking clamp bar  85 . The body of the locking clamp bar  85  also defines a threaded bore which receives a screw  86  which holds the locking clamp bar  85  in position over the yoke preventing lateral sliding of the locking clamp bar  85 . The screw  86  is threaded into the lower cross support bar  30  as can be seen in  FIG. 1 . A locking bar adjustment mechanism  88  is mounted to the base plate  22  by screws and is offset on the plate  22  in relation to the axis of the locking clamp bar  85  to allow easy access and turning by the user. The locking bar adjustment mechanism  88  is constructed with a body  90  defining a slot  91  cut therein as seen in  FIG. 3  and an axle member  92  mounted to the body as seen in  FIG. 5  extending across the slot  91 . A cam arm member  94  is pivotally mounted on the axle member  92 . The cam member  94  has a curved extension arm  95  which engages the distal end portion undersurface of the locking clamp bar  85  allowing the distal end to be moved upward or downward against the action of spring  83  carried in the bottom section of the yoke engaging the distal portion of the locking clamp bar  85 . A threaded driver  96  is mounted in a threaded bore cut in the body  90  with the end  97  of the driver  96  engaging and driving the cam member  94 . When the driver head  98  is turned clockwise the driver is rotated causing the end  97  to engage the rear end surface of the cam  94  driving the curved extension arm  95  upward against the underside of the locking clamp bar  85  so that the proximal end of the locking clamp bar  85  is driven downward against the rim of the drum holding the drum in place. Conversely when the screw is rotated counterclockwise the pressure on the underside of the locking bar is released allowing the spring  83  to bias the distal end of the locking bar  85  upward allowing the rim of the drum to be disengaged. 
   The left and right pedal assemblies  100  and  101  as shown in  FIGS. 1 ,  8 , and  9  are formed with a solid base plate  102  upon which a frame is mounted by screws  105  as shown  FIG. 9 . The frame has two upright standards  106  and  108  which are spaced and supported by a lower cross support bar  110  and an upper cross support bar  112  which have their ends mounted to the upright standards by screws which are threaded in a blind bore cut into each end of the respective cross support bar. The upright standards have a throughgoing bore drilled therethrough with an outer countersunk portion which allows the screw head to be inserted into the countersunk portion so that the screw head does not extend outside the standard. A shaft  114  is rotatably mounted in yoke  106 ( a ) and  108 ( a ) formed on the distal end of each of the standards  106  and  108 . Bearing sleeves  118  are coaxially mounted in respective yokes  106 ( a ) and  108 ( a ) allowing rotation of the shaft  114 . The shaft  114  is tensioned by a spring assembly  121  to return to a set position. The spring assembly  121  is mounted to an eye member  124  integrally formed with standard  106  and extending transverse thereto. A serrated shaft mount member  126  is fixedly mounted to a shaft extension portion  114   a  having a flat locking portion, the same as that shown in the beater assembly shaft. 
   The spring assembly  121  is constructed with an adjustable threaded eye anchor mechanism  132 , a coil spring  134  having one end  135  looped to fit into the eye of the eye anchor mechanism with the other end of the spring  136  being mounted to an aperture cut into a pivoted shaft coupler member  140 . The pivoted shaft coupler member  140  is in turn mounted on a shaft extending from an adjustable clamp member  142  which when tightened, engages and is fixed on serrated shaft mount member  126 . The adjustable clamp member  142  is tightened by a fastener screw  144  which is threadably mounted across the jaws of the clamp member  142 . These spring assemblies are constructed identical to the spring assemblies for the split beater shafts  36 / 37 . 
   A pedal  146  with a toe stop member  147  is pivotally mounted at  148  on a fixed heel plate  150  which is secured by screws  152  to the base plate  102 . The pedal  146  has its toe end mounted to a flexible coupling, such as a chain  154  which couples the forward toe end of the pedal  146  to a sprocket  150  which is preferably concentric fixedly mounted to shaft  114 . 
   Each pedal assembly shaft  114  is flexibly connected to the respective beater shaft  36 / 37  by a movable connector assembly  160  which is more clearly shown in  FIG. 7 . The movable connector assembly  160  is constructed with end cylindrical member assemblies  162  at each end. The end cylindrical assemblies  162  operate in the same manner as a ball joint. Each end cylindrical member assembly has an outer cylindrical section  164  defining a centered throughgoing bore with an inner a yoke section  165  formed at the opposite end. The cylindrical section  164  has two angularly positioned threaded bores leading into the throughgoing bore which holds the end of shaft  114  or the ends of shafts  36  or  37 . Set screws  172  and  174  are threadably mounted in the threaded bores and are tightened to allow the tips of the screws  172  to engage either the shaft extension portion  36 ( a ) or  37 ( a ) and shaft portion  114 ( a ) holding the cylindrical member assembly  162  secured to the respective shaft extension portion. The opposite end of the outer cylindrical member as noted is formed with a yoke  165  across which pin means  178  is mounted to hold rotator member  166 . The rotator member  166  which is in the form of a cylinder with opposing flat sided surfaces is mounted in the saddle of the yoke on the pin means  178  and is rotatable around the pin means  178 . The rotatable member  166  has two opposing blind bores in the flat sided surfaces positioned transverse to the axis of pin  178  to hold pin means  184  allowing the attachment of a yoke of a second cylindrical inner member assembly  182 . The second inner cylindrical member assembly  182  is shaped identical to outer cylindrical member  165  and is also mounted to the rotator member  166  by pin means  184  which extends through yoke  176  of the inner cylindrical member transverse to the axis of pin means  178 . The yokes  165  and  178  are rotated around the rotator member  166  from each other so that the yoke arms of each cylindrical member assembly extend into the saddle of the other yoke section. This allows the outer cylindrical member and inner cylindrical member to be moved with respect to each other. The cylindrical section  182  of the inner cylindrical member also is provided with a central bore and two angularly position threaded bores to hold set screws  186  allowing the same to be secured to a connector bar (not shown). The connector bar is slidably mounted within sleeve  194 . The connector bar is secured at the length desired within sleeve  194  by screws  195 . Thus the length of the connector assembly  160  can be selectively adjusted. The yokes and rotator member  166  of the cylindrical member assemblies  162  and  182  are covered with a rubber accordion cover  196  protecting the moving parts from dirt and foreign material. 
   In operation of the drum pedal device the hoop clamp  85  is mounted to the rim of a drum of a drum by turning the offset cam assembly mounted to the base plate  22 . The beater shafts  72  are mounted in the beater mounts  66 / 68  with the beater arm  72  length being adjusted by cylindrical locking stop  77  and locked in place on the respective beater mount. The beater head is positioned so that either the soft portion  76  or the hard portion  75  strikes the drum skin. The pedal assemblies  100  and  101  are positioned on opposite sides of the drum beater assembly and the shafts  114  of same are connected with the respective split shafts  36 / 37  of the drum beater assembly by connector assemblies  160 . Thus the connector assemblies  160  are secured to one end of the pedal rotating shaft  114  and the other end to the respective extending end of the split shaft  36 / 37 . The drummer&#39;s depression of the pedal  146  pulls down on linkage  154  driving the sprocket  160  and shaft  114  upon which the sprocket is mounted. The end of the shaft  114 ( a ) is connected to a connector assembly  160  which transmits the torque to one or the split shafts  36 / 37  of the beater assembly to rotate the respective shaft and the beater mount  70  which is secured to shaft  36 / 37  causing the beater head  74  to strike the drum skin. The beater heads can be operated independently or in unison by the drummer by selective operation of the respective foot pedals  146 . 
   The principles, preferred embodiments and modes of operation of the present invention have been described in the foregoing specification. However, the invention should not be construed as limited to the particular embodiments which have been described above. Instead,. the embodiments described here should be regarded as illustrative rather than restrictive. Variations and changes may be made by others without departing from the scope of the present inventions defined by the following claims.