FIELD OF THE INVENTION
[0001] The present invention relates to musical drums and a method of manufacturing the
same, and more particularly to a drum construction using a bearing edge comprising
an edge made of a resin material provided on one or both ends of a drum shell.
BACKGROUND OF THE INVENTION
[0002] The construction of musical drums varies. A typical drum comprises a cylindrical
drum shell and a drumhead mounted over one or both ends. Latches or some other suitable
devices are used to secure the drumhead to the end of the shell and then tension the
head to the desired tonality. Drum shells have been constructed out of various materials,
such as metal, wood, fiber materials and the like.
[0003] Some modern day drum shells employ a composite construction including a shell formed
of a pressed or laminated fibrous material to provide the basic rigidity and sound
qualities, and which has a suitable outer coating provided for appearance.
[0004] Drum shells made of various wood and composite materials, such as fiber or fiberglass,
tend to collapse at or along the edge of the shell over which the drumhead is mounted
and stretched. The collapse of the edge usually occurs as a result of the concentrated
stress buildup in that area brought about by the tensioning process and the constant
pounding of the drumsticks on the drumhead surface. The collapsed edge usually appears
cracked and buckled. In some cases, the fiber laminations will begin to separate and,
thus, cause a further weakening of the edge. When this occurs, the sound qualities
of the instrument begin to suffer dramatically.
[0005] To resolve these problems, attempts have been made to add a cylindrical ring inside
the shell at or near the top to provide rigidity to the end of the shell. Shells of
greater thickness can be used also, but the increased thickness adds substantially
to the weight of the shell and, consequently, the weight of the drum, making it difficult
for some drummers (e.g., youngsters) to carry the drum in parades and the like. Other
such efforts include the use of a metal bearing edge which conforms to the shape of
one or both ends of a drum shell. However, metal is a relatively heavy material and
adds to the weight of the instrument making it more difficult, for example, to carry
and play the drum in a marching band. Metal bearing edges also required the use of
screws or nails or some similar device to properly secure the metal to the drum shell.
Thus, the process in utilizing a metal bearing edge can become extremely labor intensive
adding substantially to the cost of manufacturing the instrument.
[0006] The deterioration of drum shell edges made from wood and fibrous materials, as previously
described, are not the only drawbacks associated with these materials. Edges fabricated
from these substances require a significant amount of routing, sanding and shaping
to achieve the kind of edge that is capable of effectively supporting the drumhead
and assisting in producing the most desirable tonal qualities for the instrument.
As with the metal bearing edge discussed previously, the process involved in the manufacture
of a drumshell using wood or any suitable fibrous material is also extremely labor
intensive.
[0007] Accordingly, there is a need in the art to provide a bearing edge that can be fabricated
using a technique that is not labor intensive, that can maintain its uniformity and
structural integrity over time and will continuously resist the kind of deterioration
that normally results from the severe stress buildup on the edge caused by the tensioning
process and the constant striking of the drumhead surface.
[0008] Further examples of drums of the prior art are described in EP 0 194 834 A and US
4,993,304. EP 0 194 834 A describes a musical drum comprising a shell over each end
of which is secured a drum skin. One end of the drum shell is flat, the drum skin
being secured to that flat end by means of a tensioning assembly including a pair
of hoops held in place by bolts. US 4,993,304 describes a musical drum formed from
a plurality of axially aligned rings held in position relative to each other by pins.
The outer rings may have rounded ends for contacting the drum head.
SUMMARY OF THE INVENTION
[0009] The present invention thus provides a musical drum as set forth in claim 1 below.
The present invention also provides a method of manufacturing a drum as set forth
in claim 10 below. Additional features which may optionally be used to implement the
invention to advantage are set forth in the dependent claims.
[0010] Embodiments of the present invention provide a solution to the foregoing problems
not addressed in the prior art and, in addition, enhance the sound produced by the
drum. The embodiments provide a molded resinous bearing edge or cap, preferably substantially
in the shape of an inverted "V", which is secured in the context of any conventional
molding process to the end of a drum shell formed of wood, fiber, fiberglass or the
like, and the drumhead is suitably stretched over essentially the apex of the bearing
edge. The molded resinous bearing edge strengthens the edge of the shell and eliminates
the tendency of the edge to collapse upon the tightening of the drumhead. This edge
also brightens the sound generated by the drum and, further, maintains the flatness
of the plane or line contact with the underside of the drumhead. It also provides
a minimal friction edge over which the drumhead can easily be tightened. Although
the inverted "V" shape is preferred, almost any other shape of edge would be suitable,
including a skewed shape, wherein the apex is offset to one side or another (radially
in or out from the centerline of the edge), a somewhat rounded version, or even a
flat plane.
[0011] Preferably the bearing edge is comprised of a molded resinous material devoid of
fiberglass. Preferably the drum shell is a one-piece drum shell.
[0012] Thus, the present invention can provide a considerable increase in the strength of
the drum and provides desirable and improved sound characteristics.
[0013] Accordingly, it is an object of the present invention to provide an improved drum
construction.
[0014] Another object of the present invention is to provide an improved bearing edge for
one or both ends of a drum shell formed of wood, fiber, fiberglass, plastic or similar
materials.
[0015] A further object of the present invention is to provide an improved bearing edge
preferably substantially in the shape of an inverted "V" affixed to an end of a drum
shell to strengthen the end of the drum shell, and provide a lower friction edge over
which a drumhead may be stretched.
[0016] A still further object of the present invention is to provide an improved bearing
edge affixed to one or both ends of a drum shell that will maintain its uniformity
of shape and structural integrity over time.
[0017] These and other objects and features of the present invention will become better
understood through a consideration of the following description taken in conjunction
with the drawings of examples of the invention in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0018]
- FIG. 1
- is a perspective view of a conventional drum incorporating concepts of the present
invention.
- FIG. 2
- is a cross-sectional view of a drum shell after the molded bearing edge is secured.
- FIG. 3
- is a cross-sectional view of an end of a drum shell with a molded bearing edge formed
in an inverted substantially "V" shape secured to the end of the shell.
- FIG. 4
- is a cross-sectional view similar to FIG. 3, but with the molded bearing edge formed
in an inverted substantially "V" shape with the apex offset to one side secured to
the end of the drum shell.
- FIG. 5
- is a cross-sectional view similar to FIG. 3, but with the molded bearing edge formed
rounded along the top surface secured to the end of the drum shell.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] FIG. 1 shows a drum shell 10 of conventional cylindrical form having an upper drumhead
11 and a lower drumhead 12 attached to the drum shell 10 by several sets of conventional
latches 13 and 14. U.S. Patent No. 3,647,931 illustrates one form of an exemplary
drum of the prior art.
[0020] Drum shells are made from various materials including metal, wood, fiber material
molded or layed up in a composite construction, including wood fibers, paper and/or
fiberglass fibers, plastic and the like. The present invention is directed to drums
having drum shells of non-metallic construction and will be referred to herein and
in the claims for convenience as "fiber" drum shells or drum shells of "fiber" construction
to encompass wood, plastic, fibrous and other various non-metallic drum shells. Under
the appropriate circumstances, however, the present invention may be employed with
drum shells made of metal and a variety of other substances.
[0021] FIG. 2 illustrates in a cross-sectional view a typical composite drum shell 19 with
a fiber shell 20 having a plastic outer cover 21. The shell 20 is conventional, and
is formed from wood fiber in the form of a fiber tube. A typical construction uses
fibrous paper material pressed together to comprise a laminate containing multiple
revolutions and with a wall thickness of approximately 5mm (three-sixteenths inch).
The plastic outer layer 21 can be any suitable thickness and color, and is primarily
employed for appearance and to protect the outer surface of the shell 20. The layer
21 preferably covers substantially the entire outer surface of the shell 20.
[0022] When the drumhead is tightened across the end of a conventional fiber shell 20, it
frequently is necessary to substantially stretch the head, using any conventional
tensioning mechanism. When this is done it is common over time for the edge of the
shell to deteriorate, buckle and eventually collapse. Edge deterioration will accelerate
as a result of the constant pounding of the drumstick on the drumhead surface. With
drum shells produced in accordance with prior art methods, an inverted "V" configuration
(not shown) has been provided at end of wood shells to minimize the friction of the
shell edge on the drumhead. However, the thin apex of the edge, because of its relative
fragility, contributes even more to the shell's edge collapse. Certain fiber shells,
due to this deterioration problem, soon begin to produce dull or offensive overtones,
which detract from the overall sound quality of the instrument.
[0023] FIG. 3 illustrates a preferred form of a molded resinous bearing edge 22 according
to the present invention. This molded resinous bearing edge 22 has an inverted "V"
configuration, extending downwardly from the apex into a pair of skirts 30 and 31.
Configuration of the edge 22 can be such that the apex 24 can be offset to one side
or the other or can be rounded as shown in FIGS. 4 and 5, or even somewhat flat (not
shown), if desired. The bearing edge 22 is secured to the end 26 of the fiber shell
20 by way of the natural bonding that occurs between the outer surface of the end
26 and the underside of the bearing edge 22 during the molding process. Adhesives
(not shown), such as epoxy applied between the underside of the bearing edge 22 and
the outer surface of the end 26, or some other suitable means of securing the bearing
edge 22 to the shell 20, are usually unnecessary. The bonding between the bearing
edge 22 and the outer surface of the end 26 is enhanced even further due to the constant
downward pressure exerted upon the edge 22 onto the end 26 by virtue of the tightening
of the drumhead by the tensioning mechanism. The other end (not shown) of the shell
20 as seen in FIG. 2 may have a similar construction and a molded resinous bearing
edge 22 thereon.
[0024] While any suitable resin material can be used to form the molded resinous bearing
edge 22, it has been found that the chemical compounds polyurethane or polyurea using
any conventional injection molding process to form the edge 22 to the shapes shown
in FIGS. 3 through 5 is suitable. Molded resinous bearing edge 22 extends completely
around the end 26 of the shell 20 to cover the entire end 26 and to provide a continuous
circular, substantially line contact, by the apex 24 of the bearing edge 22. This
results in a flat plane or circular line contact with the underside of the drumhead
and thereby maintains a flatness of the edge to head contact.
[0025] Accordingly, important features of the illustrated embodiment of the present invention
are the use of a molded resinous bearing edge, preferably of an inverted substantially
"V" cross-sectional configuration, on a fiber drum shell. It has been found that this
construction provides a significant gain in strength to the bearing edge allowing
the drumhead to be tensioned around a standard thickness fiber shell without the usual
risk and eventuality of a premature edge failure. The bearing edge 22 fashioned in
accordance with the present invention is precluded from deteriorating and eventual
total collapse while also providing the instrument with a brighter or sharper sound.
[0026] Mechanically, the addition of the molded resinous bearing edge 22 reinforces the
end 26 of the shell 20 both diametrically and axially. The plane of the bearing edge
at the apex 24 is maintained flat and the concentricity of the shell is maintained
round because of the shape and persistent integrity of the bearing edge 22. The apex
24 provides essentially a single circular line contact point for the underside of
the drumhead. The resulting drum will yield more varied and reliable frequencies and
the resultant sound will be considered acoustically more acceptable.
[0027] While the invention will be described in connection with a certain preferred embodiment,
it is to be understood that it is not intended to limit the invention to that particular
embodiment. Rather, it is intended to cover all alternatives, modifications and equivalents
as may be included within the scope of the invention as defined by the appended claims.
1. A musical drum comprising:
a substantially cylindrical one-piece drum shell (20) of fibre construction having
at least one end (26) over which a drumhead (11) is to be attached, said end (26)
having a substantially flat shape, and
a bearing edge (22), comprised of a moulded resinous material secured as a separate
piece to said end (26) of said shell (20),
wherein said bearing edge (22) has a cross-sectional shape having an apex (24) at
one end and a substantially flat surface at the other end, said apex (24) defining
a support and contact circle for a drumhead (11) and said end with said flat surface
of said bearing edge (22) being closely mounted on, mated with and secured to said
end (26) of said shell (20), and
said bearing edge being secured continuously around and to said end (26) of said shell
(20) by way of the natural bonding that occurs between the outer surface of said end
(26) of said shell (20) and the underside of said bearing edge (22) during a moulding
process, in which said bearing edge (22) has been formed in a mould and shaped therein
in contact with said shell (20).
2. A drum according to claim 1, wherein a drumhead (11) is stretched over said apex (24)
of said bearing edge (22) and secured to said drum shell (20).
3. A drum according to any preceding claim, wherein said bearing edge (22) extends completely
around, and covers the entirety of, said end (26) of said shell (20).
4. A drum according to any preceding claim, wherein the cross-section of said bearing
edge (22) is substantially in the shape of an inverted "V".
5. A drum according to any one of claims 1 to 3, wherein the cross-section of said bearing
edge (22) is a skewed shape, said apex (24) being offset to one side.
6. A drum according to any one of claims 1 to 3, wherein said apex (24) is rounded.
7. A drum according to any preceding claim, wherein said resinous material is devoid
of fibreglass.
8. A drum according to any preceding claim, wherein said resinous material is comprised
of polyurethane.
9. A drum according to any preceding claim, wherein said resinous material is comprised
of polyurea.
10. A method of manufacturing a musical drum comprising the steps of:
first providing a substantially cylindrical one-piece drum shell (20) of fibre construction
having at least one end (26) over which a drumhead (11) can be attached, said end
(26) having a substantially flat shape, and then
forming in a mould a bearing edge (22), comprised of a moulded resinous material,
so that said bearing edge (22) has a cross-sectional shape having an apex (24) at
one end and a substantially flat surface at the other end, said apex (24) defining
a support and contact circle for a drumhead (11),
shaping in said mould said bearing edge in contact with said shell (20), and
securing said bearing edge continuously around and to said end (26) of said shell
(20) by way of the natural bonding that occurs between the outer surface of said end
(26) of said shell (20) and the said flat surface on the underside of said bearing
edge (22) during the moulding process.
11. A method of manufacturing a drum according to any of claims 2 to 9, wherein the method
includes the steps of the method of claim 10.
1. Musiktrommel, bestehend aus:
einem im Wesentlichen zylindrischen, einstückigen Trommelgehäuse (20) aus einer Faserkonstruktion
mit mindestens einem Ende (26), auf dem ein Trommelfell (11) zu befestigen ist, wobei
das Ende (26) eine im Wesentlichen flache Form hat, und
einem Stützrand (22), der aus einem geformten Harzmaterial besteht, das als separates
Teil am Ende (26) des Gehäuses (20) befestigt ist,
wobei der Stützrand (22) eine Querschnittsform mit einem Scheitelpunkt (24) an einem
Ende und einer im Wesentlichen ebenen Fläche am anderen Ende besitzt, wobei der Scheitelpunkt
(24) einen Träger- und Kontaktkreis für das Trommelfell (11) definiert und das Ende
mit der ebenen Fläche des Stützrands (22) eng am Ende (26) des Gehäuses (20) angeordnet,
mit diesem verbunden und daran befestigt ist, und
wobei der Stützrand durch die natürliche Verbindung, die zwischen der Außenfläche
des Endes (26) des Gehäuses (20) und der Unterseite des Stützrands (22) während eines
Formvorgangs auftritt, bei dem der Stützrand (22) in einer Form vorgeformt und in
dieser in Kontakt mit dem Gehäuse (20) geformt worden ist, durchgehend um das bzw.
an dem Ende (26) des Gehäuses (20) befestigt ist.
2. Trommel nach Anspruch 1, bei der ein Trommelfell (11) über den Scheitelpunkt (24)
des Stützrands (22) gespannt und an dem Trommelgehäuse (20) befestigt ist.
3. Trommel nach einem vorhergehenden Anspruch, bei der der Stützrand (22) sich vollständig
um das Ende (26) des Gehäuses (20) erstreckt und dieses vollständig abdeckt.
4. Trommel nach einem vorhergehenden Anspruch, bei der der Querschnitt des Stützrands
(22) im Wesentlichen die Form eines umgekehrten "V" besitzt.
5. Trommel nach einem der Ansprüche 1 bis 3, bei der der Querschnitt des Stützrands (22)
eine abgeschrägte Form aufweist, wobei der Scheitelpunkt (24) auf eine Seite versetzt
ist.
6. Trommel nach einem der Ansprüche 1 bis 3, bei der der Scheitelpunkt (24) abgerundet
ist.
7. Trommel nach einem vorhergehenden Anspruch, bei der das Harzmaterial glasfaserfrei
ist.
8. Trommel nach einem vorhergehenden Anspruch, bei der das Harzmaterial aus Polyurethan
besteht.
9. Trommel nach einem vorhergehenden Anspruch, bei der das Harzmaterial aus Polyharnstoff
besteht.
10. Verfahren zur Herstellung einer Musiktrommel, bestehend aus folgenden Schritten:
Schaffen eines im Wesentlichen zylindrischen, einstückigen Trommelgehäuses (20) aus
einer Faserkonstruktion mit mindestens einem Ende (26), auf dem ein Trommelfell (11)
befestigt werden kann, wobei das Ende (26) eine im Wesentlichen flache Form hat, und
Formen eines aus einem geformten Harzmaterial bestehenden Stützrands (22) in einer
Form, so dass der Stützrand (22) eine Querschnittsform mit einem Scheitelpunkt (24)
an einem Ende und einer im Wesentlichen ebenen Fläche am anderen Ende besitzt, wobei
der Scheitelpunkt (24) einen Träger- und Kontaktkreis für ein Trommelfell (11) definiert,
Formen des Stützrands in Kontakt mit dem Gehäuse (20) in einer Form, und durchgehendes
Befestigen des Stützrands um das bzw. an dem Ende (26) des Gehäuses (20) durch die
natürliche Verbindung, die zwischen der Außenfläche des Endes (26) des Gehäuses (20)
und der ebenen Fläche auf der Unterseite des Stützrands (22) während des Formvorgangs
auftritt.
11. Verfahren zur Herstellung einer Trommel nach einem der Ansprüche 2 bis 9, wobei das
Verfahren die Schritte gemäß Anspruch 10 umfasst.
1. Tambour musical comprenant :
une caisse tambour (20) d'une seule pièce, sensiblement cylindrique et à base de fibres,
ayant au moins une extrémité (26) de fixation d'une tête de tambour (11), ladite extrémité
(26) étant de forme sensiblement plate, et
un bord porteur (22), formé en un matériau résineux moulé, fixé en tant que pièce
distincte à ladite extrémité (26) de la caisse (20),
dans lequel le bord porteur (22) présente une forme de section comportant un sommet
(24) à une extrémité et une surface sensiblement plate à l'autre extrémité, ledit
sommet (24) définissant un support et un cercle de contact de tête de tambour (11)
et ladite extrémité avec la surface plate du bord porteur (22) étant étroitement montée
sur, ajustée avec et fixée à ladite extrémité (26) de la caisse (20), et
le bord porteur étant fixé de façon ininterrompue autour et à ladite extrémité (26)
de la caisse (20) au moyen de la liaison naturelle qui se produit entre la surface
externe de ladite extrémité (26) de la caisse (20) et le dessous du bord porteur (22)
pendant un processus de moulage dans lequel le bord porteur (22) a été formé dans
un moule et y a été mis en forme en contact avec la caisse (20).
2. Tambour selon la revendication 1, dans lequel une tête de tambour (11) est étirée
sur ledit sommet (24) du bord porteur (22) et fixée à la caisse de tambour (20).
3. Tambour selon l'une des revendications 1 et 2, dans lequel le bord porteur (22) s'étend
entièrement autour, et couvre la totalité, de l'extrémité (26) de la caisse (20).
4. Tambour selon l'une des revendications précédentes, dans lequel la forme de la section
du bord porteur (22) est sensiblement en « V » retourné.
5. Tambour selon l'une quelconque des revendications 1 à 3, dans lequel la forme du bord
porteur (22) est en biais, ledit sommet (24) étant décalé vers un côté.
6. Tambour selon l'une quelconque des revendications 1 à 3, dans lequel le sommet (24)
est arrondi.
7. Tambour selon l'une quelconque des revendications précédentes, dans lequel le matériau
résineux est exempt de fibres de verre.
8. Tambour selon l'une quelconque des revendications précédentes, dans lequel le matériau
résineux comporte du polyuréthane.
9. Tambour selon l'une quelconque des revendications précédentes, dans lequel le matériau
résineux comporte une polyurée.
10. Procédé de fabrication d'un tambour musical, comprenant les étapes suivantes :
on se procure d'abord une caisse tambour (20) d'une seule pièce sensiblement cylindrique
à base de fibres, ayant au moins une extrémité (26) sur laquelle peut être fixée une
tête de tambour (11), ladite extrémité (26) étant de forme sensiblement plate, puis
on forme, dans un moule, un bord porteur (22), formé en un matériau résineux moulé,
de sorte que le bord porteur (22) présente une forme de section comportant un sommet
(24) à une extrémité et une surface sensiblement plate à l'autre extrémité, le sommet
(24) définissant un support et un cercle de contact d'une tête de tambour (11),
on forme, dans le moule, le bord porteur en contact avec la caisse (20), et
on fixe le bord porteur de façon ininterrompue autour et à ladite extrémité (26) de
la caisse (20) au moyen de la liaison naturelle qui se produit entre la surface externe
de ladite extrémité (26) de la caisse (20) et ladite surface plate sur le dessous
du bord porteur (22) pendant le processus de moulage.
11. Procédé de fabrication d'un tambour selon l'une quelconque des revendications 2 à
9, comprenant les étapes du procédé de la revendication 10.