[0001] This invention relates to a tambourine frame structure for playing with small balls
and the like.
[0002] To obtain an implement with good characteristics, it is known that the membrane of
tambourine must be stretched on the frame with considerable force.
[0003] In addition to this routine stress, the frame is also subjected to the stresses generated
while practicing the game.
[0004] For these reasons, the traditional wooden frame has been abandoned in favor of stronger
frames of plastics, which fail, however, to satisfactorily solve the deformation problem.
[0005] That deformation revealsitself both in the frame getting out of round, twisting,
and breaking, especially along the opposite edge to the edge whereon the membrane
is stretched. In fact, the impact stress of the ball onto the membrane behaves as
the power of a first order lever having its fulcrum located at an approximately middle
region of the frame, and the resistance at the opposite edge of the membrane.
[0006] In order to obviate said breaking effect, during the molding stage, undisclosed attempts
have been made to embed a wire length into the stressed edge. However, this solution
remained disadvantageous in that the center of gravity of the tambourine moves away
the membrane, thus creating problems of unbalance upon fitting the ball.
[0007] Accordingly the task of this invention is to provide a tambourine frame structure
which can obviate the problems and deficiencies of prior ones.
[0008] Within this task it is an object of the invention to provide such a structure which
is as far as possible indeformable under the stresses imposed by both the membrane
tension and the playing activity.
[0009] Yet another object is to provide such a structure which can be readily implemented
with conventional techniques and equipment.
[0010] The aforesaid task and objects as well as yet other objects which will be more apparent
hereinafter, are achieved by a tambourine frame structure, comprising a substantially
cylindrical frame with an outer and an inner periphery thereof and a stretched membrane
extending over the area encircled by said frame and fixed on said frame, characterized
by a metal ring member circumferentially coextensive with said cylindrical frame and
having at least one portion thereof in stress resisting circumferential engagement
with at least one longitudinal part of said cylindrical frame.
[0011] Further features and advantages of the invention will be more clearly understood
from the following detailed description of a preferred embodiment, given herein by
way of example and not of limitation, and illustrated in the accompanying drawings,
where:
Figure 1 is a perspective partly sectioned view illustrating a tambourine frame structure
according to the shown embodiment;
Figure 2 is a fragmentary sectional view taken along the line II-II of Figure 1;
Figure 3 is a sectional view through the metal ring associable to the subject tambourine
frame structure; and
Figures 4 and 5 illustrate variations of the ring shown in Figure 3.
[0012] With reference to the drawing figures, the shown tambourine frame structure comprises
a frame 1, of substantially cylindrical configuration, whereon a membrane 2 is stretched
in a conventional known way, whereby a cylindrical flap 2' of the membrane strongly
adheres against the side wall of the frame 1.
[0013] More specifically the frame 1 may be conveniently formed by any suitable plastics
material injection process.
[0014] During assembling, a metal ring 3 is inserted between the frame and membrane,which
ring is configured such that, in cross-section, it comprises a lip 4 engaging with
an edge thereof into a seat 1' formed on the outer periphery of the frame 1, and a
rounded ,region 5 provided for contacting the membrane, and an inner flange formation
6.
[0015] It should be noted that the cited three parts of the reinforcing ring 3 are an integral
construction, and so configured as to react to stresses regardless of how applied,
thus preventing both twisting and out-of-round problems in the tambourine frame.
[0016] The rounded portion 5 of the ring 3 serves the purpose to gradually distribute the
stresses acting on the membrane.
[0017] In a simplified embodiment, the ring 3 may be cylindrically configured as shown in
Figure 4, to only resist stresses tending to twist the frame; in this case it may
be advantageously embedded in the frame and arranged in the seat 1" provided on the
inner periphery of the frame 1.
[0018] According to yet another variation, shown in Figure 5, the ring has a flat shape
lying in a plane perpendicular to the axis of the frame 1 and arranged in the seat
1" thereby being effective to prevent the frame from getting out of round.
[0019] Obviously it should also be noted that, during the frame forming operation, one or
more such rings may be inserted, depending on the tambourine height and the stresses
which the tambourine structure is to withstand.
[0020] In addition to the cited advantage of structural strength, with metal rings of the
type illustrated, the center of gravity of the tambourine is brought closer to the
membrane, with considerable attendant improvement in stability and controllability
as the ball is being hit.
[0021] Of course, such rings and the frame may have any desired size, and the material employed
may be any selected one for the intended application.
1. A tambourine structure, comprising a substantially cylindrical frame (1), with
an outer and an inner periphery thereof and a stretched membrane (2) extending over
the area encircled by said frame (1) and fixed on said frame (1), characterized by
a metal ring member (3) circumferentially coextensive with said cylindrical frame
(1) and having at least one portion thereof in stress resisting circumferential engagement
with at least onelongitudinal part of said cylindrical frame (1).
2. A tambourine structure according to Claim 1, wherein the membrane (2) has a circular
flap (2') which extends with its edge over said outer periphery of said cylindrical
fram (1), characterized in that said ring member (3) has at least one portion ( 4)
thereof in circumferentially mating engagement with at least one longitudinal part
of said outer periphery, said portion (4) of said ring member (3) being arranged between
said membrane flap (2') and said outer periphery to thereby take over the tension
stresses exerted by the membrane (2).
3. A tambourine structure according to Claim 1, characterized in that said ring member
(3) has a cross-section with a first annular portion (4) associated with said outer
periphery (1) and extending normal to the membrane (2) plane and a second annular
portion (6) extending substantially parallel to said membrane (2) plane.
4. A tambourine structure according to Claim 3, characterized in that said two portions
(4,6) forming said ring member (3) are joined together by an arcuate region (5) in
direct contact with said membrane (2).
5. A tambourine structure according to one or more of the preceding claims, characterized
in that said ring member (3) is shaped as a sleeve coaxial with the axis of said cylindrical
frame and in abutment engagement with said inner periphery.
6. A tambourine frame structure according to Claim 1, characterized in that said ring
member is flat and in abutment engagement with said inner periphery.
7. A tambourine frame structure, substantially as herein described and illustrated.