Connecting structure for the separable part of a dual drum pedal

A connecting structure for connecting an inner and an outer rod wherein at least one and more typically two screws at circumferentially spaced apart locations attach the inner and outer rods. An elastic seating plate has an insertion opening in from one side edge followed by a compressive enveloping opening therein which envelopes each of the screws and is also positioned radially outward of the outer rod, so that when the screws are released from the outer rod, they do not fall away from the seating plate. This also prevents idling of the screws. The connecting structure is usable on a drum pedal where a remote pedal is operated for operating a drum beater through a connecting rod on which there is at least one of the connecting structures.

BACKGROUND OF THE INVENTION 
The present invention relates to a dual drum pedal and particularly to the 
connecting structure between the separable parts of the dual drum pedal. 
PRIOR ART EMBODIMENT 
FIGS. 7-10 show a prior art embodiment of a dual drum pedal. A dual drum 
pedal P1 includes two drum head beaters 12 and 22, which are respectively 
operated by the right and left feet of a performer, for beating a single 
bass drum D. Both beaters 12 and 22 are supported for swinging on the 
frame 11 of the first pedal 10. A rotary shaft 23 on which the second 
beater 22 is supported for rotation is provided on the frame 11 of the 
first pedal 10. The rotary shaft 13 for the first beater 12 is also 
provided on the frame 11. The rotary shaft 23 is connected with the 
operating shaft 28. The shaft 28 is rotatably operated by the second pedal 
20 which is separate from the said first pedal. A connecting rod 40 joins 
the shafts 13 and 28. The bass drum D includes a drum head Da, a drum body 
Db and a drum hoop Dc. 
There is a first pedal plate 10A for the performer's right foot. The pedal 
plate 10A is pivotally supported to the first pedal frame 11. An operating 
member 14, such as a sprocket, etc. is installed on the first beater 
rotary shaft 13. A chain, a belt, or the like connects the first pedal 
plate 10A and the operating member 14. There is an installation member 16 
for the first beater 12, a cam 17 for the first beater rotary shaft 13, a 
return spring 18 provided on the cam 17 and a drum hoop clamp 19. 
The second beater rotary shaft 23 for the second beater 22 is also provided 
on the first pedal 10 and its frame 11. An installation member 24 installs 
the second beater 22 on the second beater rotary shaft 23. There is a 
respective cam 25 for the second beater rotary shaft 23. A spring 26 
provided on the cam 25 is for restoring its original orientation. A 
bearing 27 between the shaft 23 for the second beater and the first shaft 
13 provides linked integration of the first beater rotary shaft 13 and the 
second beater rotary shaft 23 in a manner permitting each of them to be 
freely rotatable in a mutually independent manner. 
The second pedal 20 includes a second pedal plate 20A for the performer's 
left foot, a second pedal frame 21 on which the plate 20A is rotatably 
supported, a second operating shaft 28 which is rotatably operated by the 
second pedal plate 20A, an operating member 29, such as a sprocket, etc. 
for rotating the operating shaft 28 and a chain, belt, etc. 30 for joining 
the second pedal plate 20A and the operating member 29. 
A connecting rod 40 transmits the rotation of the second operating shaft 
28, which is caused by operation of the pedal plate 20A of the second 
pedal 20, to the second beater rotary shaft 23 supported on the first 
pedal 10. The rod 40 is joined with the operating shaft 28 at one end and 
with the second beater rotary shaft 23 at the other end through the 
respective universal joints 45 and 46 at both ends of the rod 40, so that 
the first pedal 10 and the second pedal 20 may be freely arranged by a 
performer at any orientation with respect to each other, to be selected by 
the performer using the pedals. A respective fixing screw 47 links each 
universal joint 45 and 46 with the respective second beater operating 
shaft 23 and the operating shaft 28. 
The connecting rod 40 ordinarily has a flexible structure which enables the 
distance and the relative orientations between the first pedal 10 and the 
second pedal 20 to be set for the convenience of the performer. The 
connecting rod 40 includes a first rod 41 linked to the universal joint 45 
on the side of the first pedal 10 and a second rod 42 linked to the 
universal joint 46 on the side of the second pedal 20. The rods 41 and 42 
are provided in a hollow main pipe 43 so as to slide freely therein. The 
positions of expansion and contraction of the distance between the pedals 
are fixed by the fixing screws 44 that have been screwed to both ends of 
the main pipe 43 and press against the respective pipes 41 and 42 within. 
The first pedal 10 and the second pedal 20 are linked together by a linking 
rod 40 in the dual drum pedal during their use at a performance. But they 
may have to be separated for storage or transportation. The separation 
will naturally have to be done at the linking part, and is normally done 
as shown in either of FIGS. 9 or 10. 
In FIG. 9, the fixing screws 47 for both universal joints 45 and 46 on both 
sides of the linking rod member 40 are loosened, for releasing the union 
between the second beater rotary shaft 23 of the first pedal 10 and the 
operating shaft 28 of the second pedal 20 and dividing the pedal into 
three parts. 
FIG. 10 shows the fixing screw 44 for fixing one of the rods of the linking 
rod member 40, the first rod 41 in the drawings, to the main pipe 43 being 
loosened, enabling withdrawal of the first rod 41 from the main pipe 43 
and dividing the pedal into two parts. 
However, the fixing screws 47 and 44 remain screwed on their various 
respective parts after a separation of the pedals at the connecting rod 40 
into two or three parts. Because no load is applied to these fixing screws 
after the separation of the parts, idling may develop due to vibrations or 
shocks. For example, loosened fixing screws may drop out due to an impact 
delivered at the times of shifting or of transportation by a vehicle, etc. 
Since this type of fixing screw is small in size, they tend to be lost if 
dropped. 
Because the fixing screw is used in fixing the connecting rod 40, which is 
essential for transmitting the action of the second pedal 20, the possible 
loss of the fixing screw makes it nearly impossible to carry out a 
performance with the dual drum pedal. 
SUMMARY OF THE INVENTION 
This invention has an object of providing a simple structure for preventing 
idling of the remaining fixing screws at the separating part and for 
preventing loss of the screws due to their dropping out. 
The invention concerns an improvement in the dual drum pedal of the prior 
art for the purpose of holding the fixing screws used for the connecting 
rod so that they do not fall free of the part of the drum pedal at which 
they remain when the drum pedal is separated into parts for storage, 
transportation, etc. As in the prior art, the dual drum pedal has a first 
and a second drum beater which are supported on the frame for the first of 
the pedals, has a second pedal, which is normally supported at a distance 
from the first pedal on a separate second pedal frame, and has a 
connecting rod between the second pedal and the second shaft which is 
rotated by the second pedal for connecting the second shaft to the rotary 
shaft for the second beater located at the first pedal. Further, when 
necessary, the two drum pedals should be separated into separate units at 
least at a connection between one of the drum pedals and the connecting 
rod between the drum pedals. 
There is a connection from the connecting rod between the two drum pedals 
with the rotary shaft that is connected that is to the second drum beater 
located at the first pedal frame and with the rotary shaft connected to 
the second drum pedal and located at the second pedal frame. That 
connection is obtained by respective fixing screws. There are fixing 
screws at the connections between the connecting rod and the respective 
rotary shaft at the second pedal, on the one hand, and the rotary shaft at 
the second drum beater at the other hand. 
The connecting rod between the rotary shaft at the second pedal and the 
rotary shaft at the second beater is comprised of two separate rod 
sections with a hollow sleeve or tube around them, wherein the two rod 
sections can be moved together or apart, shortening or lengthening the 
rod. There are respective fixing screws at each end of the tube or sleeve 
and which are tightened against the respective first and second relatively 
movable rod sections for setting the length of the connecting rod between 
the second pedal rotary shaft and the second beater rotary shaft. This 
enables adjustment of the spacing between the second pedal and the second 
drum beater for the particular performer. 
According to the invention, at each of the fixing screws, an idling 
preventive part or element is provided which is wrapped around the screw 
at the part where the screw is supported and which remains installed in 
place between the two elements, i.e. the parts of the connecting rod and 
the connection between a universal joint and a shaft, where the respective 
screw is supported. 
Other objects and features of the invention are explained below with 
reference to the accompanying drawings.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
The dual drum pedal P shown in FIGS. 1 and 2 has essentially the same 
construction as the prior art dual drum pedal P1 in FIGS. 7 through 10, 
except for the structures at the separating parts at the linking rod 40 at 
S1 and S2. Therefore, the same reference numbers are used without further 
explanation. 
In the dual drum pedal P of the invention, a second beater rotary shaft 23 
for the second beater 22 is provided on the first frame 11 of the first 
pedal 10. The first pedal rotates the first beater rotary shaft 13 for the 
first beater 12 as described earlier. The second beater rotary shaft 23 at 
the first pedal 10 is driven by the operating shaft 28 that is rotatably 
operated by the second pedal 20 on the second frame 21. The rotary shafts 
23 and 28 are arranged at a distance by the connecting rod 40. In 
addition, the dual drum pedal P is so constructed that it can be divided 
freely through the loosening of the fixing screws 47 and 44, which are 
placed similarly as in FIG. 8, at the separating parts S1 and S2 at both 
ends of the rod 40. 
As shown in FIG. 3, there is a pair of arcuately spaced apart fixing screws 
47 around the shaft 23 or 28 at each universal joint. According to the 
invention, the fixing screws 47 are installed on the universal joints 45 
and 46 and the shafts 23 and 28, not loosely, as in FIGS. 7 and 8, but 
through the first elastic material seating plate 50, which is made of 
rubber or plastic, etc. which is located at the separating part S1, as 
seen in FIG. 3 and which wraps around the exterior of the universal joint. 
In this example, each first elastic seating plate 50 has an inner surface 
which has an arcuate curvature that conforms to the outer shape of the 
respective universal joints 45 and 46, around which each plate 50 is 
wrapped. When the screws are separated from the universal joints, the 
plates 50 remain with the screws. Hence, the connections of the universal 
joints to the rod 40 is through seating plates 50. 
At the separating parts S2, the fixing screws 44 are installed at both ends 
of the main pipe 43 after passing through the second elastic seating 
plates 60 which are also made of rubber or plastic, etc. as seen in FIG. 
5. In this example, further, the second elastic seating plate 60 has a 
planar shape that corresponds to the shape of the upper surface of the 
main pipe 43, as shown in FIG. 6. 
The elastic seating plates 50 and 60 of FIGS. 4 and 6 have respective 
idling preventive parts 51 and 61 which include the insertion openings 52 
and 62 for the compressive insertion of the threaded screw parts 47a and 
44a of the fixing screws 47 and 44 from the sides 47b and 44b and includes 
the screw enveloping parts 53 and 63 linked to the insertion openings 52 
and 62 and that envelope the screw parts 47a and 44a. 
The screw enveloping parts 53 and 63 have respective inner diameters which 
are smaller than the outside diameter of the screw parts 47a and 44a of 
the fixing screws 47 and 44 but larger than the width of the insertion 
openings 52 and 62. Because of this, radially inwardly directed pressure 
is applied by the inner surfaces of the enveloping parts 53 and 63 against 
the screw parts 47a and 44a of the remaining fixing screws 47 and 44 after 
the fixing screws 47 and 44 in the separating parts S1 and S2 have been 
loosened, as described later. There is resistance, i.e., friction 
resistance, against the rotation of the fixing screws 47 and 44 in the 
loosening direction, thereby preventing idling of the fixing screws 47 and 
44. 
Since the elastic seating plates 50 and 60 have insertion openings 52 and 
62 as described, it is possible to compressively insert the screw parts 
47a and 44a of the fixing screws 47 and 44 from the sides 47b and 44b into 
the insertion openings 52 and 62 when the dual drum pedal P is assembled. 
In this connection, the peripheries of the insertion openings 52 and 62 are 
elastically deformed so as to expand the insertion openings 52 and 62. 
This makes it possible to compressively insert the screw parts 47a and 44a 
of the fixing screws 47 and 44 into the insertion openings 52 and 62 from 
the sides 47b and 44b, thereby installing the elastic seating plates 50 
and 60 by enveloping them at the screw enveloping parts 53 and 63. This 
enables the dual drum pedal P to be easily assembled. 
In this embodiment, the elastic seating plate 50 (60) has two idling 
preventive parts 51 (61) for the two fixing screws 47 (44). There is a 
deformable cut part 55 (65) formed between the two idling-preventive parts 
51 (61). 
With two idling preventive parts 51 (61) at the elastic seating plate 50 
(60) as described above, after the loosening of the fixing screws 47 (44), 
even if one fixing screw and the elastic seating plate might rotate 
together, that rotation can be prevented by the other fixing screw. 
The cut part 55 (65), which is capable of being deformed, between the two 
idling preventive parts 51 (61) as described above, is effective during 
the compressive insertion of the screw part 47a (44a) of the fixing screw 
47 (44) into the insertion opening 52 (62) from its side 47b (44b), to 
enable the peripheries of the insertion openings 52 (62) to elastically 
deform so as to smoothly expand the openings 52 (62), thereby making it 
possible to smoothly insert the fixing screws 47 (44) into the insertion 
openings 52 (62). As a result, the operability for the installation of the 
dual drum pedal P can be improved. 
The dual drum pedal P having the connecting construction of the linking rod 
member can be divided in two or three parts at the separating parts S1 or 
S2, as is shown in FIG. 9 or 10 in connection with the explanation of the 
conventional technology. As was pointed out as to the prior art design, 
moreover, the fixing screws 47 and 44 remain screwed to the separating 
parts S1 and S2. 
Here, the fixing screws 47 and 44 that have remained in the separating 
parts S1 and S2 as they were loosened as described earlier receive 
inwardly directed pressure from the inner walls of the screw enveloping 
parts 53 and 63 of the idling preventive parts 51 and 61 of the elastic 
seating plates 50 and 60 (resistance against idling) at the screw parts 
47a and 44a. This, in turn, holds the plates 50 and 60 to the respective 
screws. Therefore, there is no possibility for idling due to the 
vibrations or shocks received during the movement or transportation by a 
vehicle, etc. This can prevent the fixing screws 47 and 44 from being 
dropped and lost from the separating parts S1 and S2. 
In the connecting structure of the connective rod member in the dual drum 
pedal of the invention, the fixing screws are installed through respective 
elastic seating plates which are equipped with an idling preventive part. 
This makes it possible, by an extremely simple construction, to prevent 
idling of a fixing screw that remains in the separating part and prevents 
the screw possibly falling out and being lost during transportation, etc. 
At the idling preventive part of the elastic seating plate, the insertion 
hole for compressive insertion from the side of the screw part of the 
fixing screw is continuous with the screw enveloping part. This makes it 
possible to install the elastic seating plate after the installation of 
the fixing screws at the separating part at the time of assembly, thereby 
making it possible to easily assemble the dual drum pedal. 
If the elastic seating plate includes two idling-preventive parts for the 
two fixing screws, even if one fixing screw and the elastic seating plate 
could start rotating together after the loosening of the fixing screws, 
that rotation can be prevented by the other one of the fixing screws. 
If a cut region of the plate that can be deformed is formed between the two 
idling preventive parts, it becomes possible to compressively insert the 
screw parts of the fixing screws smoothly into the insertion openings of 
the idling-preventive parts, which makes it easier to assemble the dual 
drum pedal. 
Although the present invention has been described in relation to particular 
embodiments thereof, many other variations and modifications and other 
uses will become apparent to those skilled in the art. It is preferred, 
therefore, that the present invention be limited not by the specific 
disclosure herein, but only by the appended claims.