Field of Invention
[0001] The invention relates to rackets or bats for paddle games and the like, in particular
for rackets used in padel tennis sports, a sport also commonly referred to simply
as padel or paddle.
Background of Invention
[0002] Current padel rackets, as described for example in
ES 2 255 419 A 1, comprise a frame enclosing a striking plane, wherein both surface sides of the striking
plane can be used to hit a ball.
[0003] Said frame usually consists of two racket frame parts molded together with the striking
plane in a racket mold press, and wherein said frame parts comprise tube elements
following the contour of the racket frame, for example a first rigid tube element
containing a second flexible inflatable tube element.
[0004] Said tube elements inter alia allow the frame parts to withstand the pressure forces
during union of the frame parts in the racket mold press and to achieve a desired
stiffness of the produced racket.
[0005] However said tube elements may also lead to an unwanted inhomogeneity in the produced
racket, such as for example frame sections of lowered densities, and which may lead
to unwanted vibration and handling properties of the racket during impact interactions
with the gaming object, e.g. the ball.
[0006] Furthermore the current state-of-the-art production of padel rackets is a rather
lengthy and complex process, inter alia requiring for example the step of inflating
the flexible tube elements.
Summary of Invention
[0007] The objective technical problem to be solved is then to improve a racket for padel,
in particular with respect to its structure, handling properties and production process.
[0008] This said problem is solved by a racket for padel according to claim 1 and padel
racket production method according to claim 9. Preferred embodiments are disclosed
in the dependent claims.
[0009] A racket for padel according to the invention can comprise two opposed striking surfaces,
and can further include a first racket half, which can have a first handle portion
and a first main portion, wherein said first main portion can comprise a first striking
surface portion, and said racket further can have a second racket half, which can
comprise a second handle portion and a second main portion, wherein said second main
portion can comprise a second striking surface portion.
[0010] Said padel racket can comprise at least one core component disposed between said
racket halves, wherein said core component has two opposed surfaces, that can follow
at least in parts the shape of the two opposed striking surfaces of the racket and
said core component can have a lateral surface.
[0011] In particular said core component can be compressible, and can be wrapped up in a
fabric component, wherein said fabric component can cover at least in parts the lateral
surface of the core component. Said fabric component can be heat-curable and for example
comprise fibres and a cured resin, wherein the resin and the fibres can be for example
cured by heat and/or radiation and/or a chemical polymerisation initiation.
[0012] Said core component can be mounted with a pre-load, i.e. with an initial tension,
between the racket halves, and as a consequence of said pre-load, said core component
can be configured to press said fabric component against the inner lateral surfaces
of the first and the second racket half, and wherein the fabric component can bond
the first and second racket half together.
[0013] Advantageously a racket according to the invention does not need to comprise a rigid
or flexible and/or inflatable or inflated tubelike element inside the racket, for
example close to the perimeter or to enclose a core component.
[0014] In other words the invention can provide a tubeless racket for padel, which can offer
superior stability and/or handling properties as compared to for example rackets comprising
tube-like elements.
[0015] Furthermore the two racket halves can be symmetric, i.e. of equal shape, but they
can also be asymmetric, wherein for example one racket half can comprise protrusions
or lateral side walls which can extend partly or fully into the other racket half,
when the two racket halves are mounted and joined together.
[0016] As fabric component materials for example carbon fibre, carbon fibre composites or
the like may be used, or any other fabric material which in combination with plastic
resins can form fiber reinforced polymers with high specific strengths, for example
with specific strengths (also referred to as strength-to-weight ratio) greater than
300 kN m / kg.
[0017] A racket according to the invention advantageously provides a simpler and more homogeneous
structure, resulting inter alia in better gaming and handling properties of the racket
in general, and in particular in reduced unwanted vibration during impact of a ball
on the striking surface, and further can lead to an enlarged sweet spot, which for
example may be defined as the region of the striking surface where the coefficient
of restitution is a maximum, i.e. the region of the striking surface which for a given
striking effort results in an optimal racket response and where the gaming object,
the ball, absorbs the maximum amount of available kinetic energy.
[0018] Also the optimized structure of a racket according to the invention allows for a
more efficient production method of the same.
[0019] The aforementioned core component of the racket can be made of solid material or
foam, for example polymeric foam and/or elastomeric foam, or comprises at least two
material layers or has honey-comb structure, or can be a combination of said material
structures.
[0020] For example the core component material can preferentially be of low density, for
example in the range of 20 to 55 kg/m
3, and may preferentially comprise an polymeric foam and/or elastomeric foam, and for
example comprise ethylene vinyl acetate (also known as EVA) and/or polyurethane (PU),
but also other low density polymer materials, respectively other low density elastomeric
foams, in particular thermoplastic elastomer materials may be used to construct the
core component.
[0021] When heated to a maximum racket mold temperature, the core component material preferably
may have little or no significant extension of its volume.
[0022] The core component can have an average uncompressed thickness, i.e. the average thickness
before the core is compressed, between 35 to 45 mm, preferentially of 38 ± 3 mm, or
40 ± 3 mm, or 42 ± 3 mm.
[0023] The core component may be divided into two separate individual parts, a handle core
part and a main core part, wherein the main core part can comprises two opposing striking
surface portions.
[0024] The handle core part and the main core part can have an equal average uncompressed
thickness or they can have a different average uncompressed thickness lying in the
range specified above. Also the handle core part and the main core part can be made
of the same core component material or they can be made of different core component
materials, chosen for example from the core component materials listed above. For
example said core parts can be made of low density elastomeric foam, with for example
densities in the range of 20 to 55 kg/m
3.
[0025] For example the handle core part can preferentially be made of PU foam and the main
core part of EVA or vice versa or each be made of a mixture of PU and EVA or each
be made of a mixture of other of low density elastomeric foams, with densities chosen
from the range specified above.
[0026] Said handle core part can be wrapped up entirely in a fabric component, wherein said
fabric component is for example made of any of the above mentioned fabric component
materials, or it can only be partially wrapped up in said fabric component.
[0027] The handle core part and the main core part can be wrapped up using the same fabric
component material or said core parts can be wrapped up partially or entirely with
different fabric component materials.
[0028] The use of different fabric component materials may inter alia enable to customize
the racket handling properties according a desired handling property, depending for
example of the skill or preferences of a player.
[0029] The racket halves can be realized as unibodies, which advantageously can also provide
better handling and stability properties.
[0030] Alternatively however the main portion and the handle portion of a racket half may
also be realized as separated parts, bonded together with bonding means, such adhesives,
resins and/or bolts and or screws or the like.
[0031] The main portion of a racket half has a substantially U-shaped or pan-shaped profile,
with the striking surface portion extending substantially flat between an edge portion,
for example an peripheric edge portion, of said main portion of a racket half.
[0032] The edge portion may be part of the striking surface portion or said edge portion
may fully or partially delimit the striking surface portion.
[0033] For completeness we note that said edge portion, respectively peripheric edge portion,
can extend fully or partially around the striking surface portion.
[0034] For example said peripheric edge portion can forms sidewalls, which can delimit the
striking surface portion of said main portion of a racket half.
[0035] The elevation or height of said sidewalls above the striking surface portion can
be equal along the peripheric edge portion or said sidewall elevation can vary continuously
or discretely along the peripheric edge portion.
[0036] For example the sidewalls may continuously reduce their height to zero or close to
zero towards a transition portion between the main portion and the handle portion
of the racket.
[0037] The peripheric edge portion may have lateral side surfaces, which can be flat or
curved, for example having a convex or concave curvature.
[0038] The final racket may also comprise bores or holes or openings extending through the
racket, for example trough the main portions and through the opposed striking surfaces,
allowing air to pass through said bores, opening or holes, in order to optimize the
weight and/or air resistance properties of the racket.
[0039] According to the invention a racket with some or all of the features describes as
above can be produced by a method, which can comprise all, some or parts of the following
steps.
- The inner surface of a first racket half and a second racket half can be coated with
a heat curable resin.
- The core component can be wrapped partially or fully in a fabric component, which
can cover at least the lateral surface of the core component.
- The fabric wrapped core component can be inserted into the first racket half under
compression of said core component, such that the core component can be pre-loaded,
i.e. can comprise an initial tension, and can press the fabric component against the
inner lateral surface of the first racket half
- The two racket halves containing the wrapped core component can be mounted together,
such that the wrapped core component can press against the inner lateral surfaces
of the first and the second racket half.
- The racket halves containing the wrapped core component can be bonded together by
bonding means, which can include heating the two racket halves containing the wrapped
core component inside a racket mold or racket mold press.
[0040] Preferred maximum heat temperatures can lie in the range of 20 to 90 ° C, preferably
around 65 ± 5 ° C and preferred ranges of time the racket halves / the racket spends
in the racket mold can lie between 15 to 45 min.
Short Description of Figures
[0041] The following figures serve as exemplary embodiments of the invention.
Fig. 1: Racket
Fig. 2: Side view of a racket
Fig. 3: Racket half
Fig. 4a: Handle core part
Fig. 4b: Alternative handle core part
Fig. 5: Main core part wrapped in a fabric component
Fig. 6: Interior structure of a racket
Fig. 7a: Profile of main portions of a racket
Fig. 7b: Alternative handle core part
Fig. 7c: Alternative handle core part
Detailed Description of Figures
[0042] Fig. 1 shows a schematic top view of an exemplary racket 100 according to the invention
made of two, preferentially symmetric, racket halves, wherein only a first racket
half 107 is visible. Said first racket half 107 can have a first handle portion 102
and a first main portion 101, wherein said first main portion can comprise a first
striking surface portion 103.
[0043] The same holds for the not visible second racket half, which can have a second handle
portion and a second main portion, wherein said second main portion can comprise a
second striking surface portion.
[0044] The handle portion can comprise a transition portion that is in connection with the
main portion. Shown here for example is the transition portion 105 of handle portion
102, which can connect the handle portion 102 to main portion 101.
[0045] Furthermore the transition portion can for example have an opening, which can extend
through the racket, e.g. through the transition portion of the handle portions of
the two racket halves. Shown here for example is a trapezoidal shaped through opening
106 in transit portion 105, but other shapes or no through opening at all are also
possible.
[0046] The striking surface portion can extend over the complete area of the main portion
of a racket half. In other words the striking surface portion can include the edge
portion of main portion.
[0047] The main portion can comprise a generic edge portion or edge portion geometry, for
example a peripheric edge portion 104, is shown here for illustrative purposes only.
The exact shape and extent of said edge portion can vary, it can be continuous or
discrete and/or can vary in its average extent and/or average thickness or height.
Some more specific examples will be described below.
[0048] The line from A to B denotes a cut through the profile of the main portions of the
racket halves of racket 100. Exemplary profiles along said lines are shown in Figs.
7a, 7b and 7c.
[0049] Fig. 2 is an exemplary schematic side view of a racket 200 analog or identical to the racket
100 of Fig. 1. Therein two racket halves, a first racket half 203 and a second racket
half 204, connected along the plane 215, are visible. Further marked are a first handle
portion 205 and a first main portion 211 of first racket half 203, and a second handle
portion 206 and a second main portion 212 of second racket half 204.
[0050] The two handle portions 205, 206 can comprise transition portions 209, 210 connecting
said handle portions 205, 206 to the corresponding main portions 211, 212. The transition
portions 209, 210 can have through openings (not shown) analog to the through opening
shown in Fig. 1.
[0051] The main portions can comprise a striking surface portion and an edge portion, i.e.
first main portion 211 can comprise first striking surface portion 201 and first edge
portion 207, and second main portion 212 can comprise second striking surface portion
201 and second edge portion 208.
[0052] The racket 200 can have an average thickness 213 across its opposing, preferred substantially
flat, striking surface portions 201, 202 between 30 to 38 mm, or up to 45 mm. The
handle of racket 200 can have an average thickness 214 across its opposing handle
portions 205, 206 which is equal or different from the average thickness across the
opposing surface portions 201, 202. Said thicknesses 213, 214 may also vary also along
and/or over the extent of the racket halves 203, 204.
[0053] Fig. 3 exemplary shows a view onto the inner surface an exemplary racket half 300 which
is analog or identical to the racket halves as previously described. Said racket half
300 can be a unibody. It can be pan-shaped, respectively can a have U-shape profile.
[0054] The racket half 300 can have sidewalls 304 extending along the main portion 302 and
the handle portion 301. The sidewalls 304 can have an from the outside visible average
height between 38/2 to 50/2 mm, which can also vary between main portion 302 and handle
portion 301 and along said portions. The end portion 307 of handle portion 301 may
be open (as shown) or can also be delimited by said sidewalls.
[0055] As mentioned before the two racket halves forming a racket can be symmetric, but
need not be symmetric. For example the sidewalls 304 of racket half 300 may be configured
in such way, as to protrude partly or fully into a (not shown) second racket half,
and the sidewalls (not shown) of said second half (not shown) may enclose partly or
fully the sidewalls 304 of racket half 300.
[0056] For completeness the striking surface portion 303 of the main portion 302 as well
as an optional edge portion 306 and a possible transition portion 308, the part of
the handle portion 301 which connects to the main portion 302, are also marked.
[0057] Fig. 4a and
Fig. 4b exemplary show two possible differently shaped handle cores 401, 402 for cases wherein
the core component of the racket is divided into two separate individual parts, namely
a handle core part 401, 402 and a main core part.
[0058] Handle core 401 has trapezoidal transition part 403 to connect with a main portion
(not shown) of a racket (not shown) and handle core 402 has a Y-shaped transition
part 404 to connect with a main portion (not shown) of a racket (not shown).
[0059] Said handle cores 401, 402 may be wrapped up partially or entirely in a fabric component
(not shown).
[0060] Fig. 5 shows an exemplary main core 500, respectively main core part, of a racket according
to the invention, wherein said main core 500 has an average uncompressed thickness
501 of 35 to 45 mm (i.e. the average thickness of said main core 500 when it is not
compressed) and is wrapped up partially in a fabric component 503, which covers the
lateral surface 502 of the main core 500 and partly its two opposed surfaces following
at least in parts the shape of the two opposed striking surfaces (not shown) of the
racket (not shown), from which only surface 504 is visible in the Figure.
[0061] Fig. 6 shows part 600 of an exemplary internal structure of a racket according to the invention.
Therein two separate core components a handle core 607 and a main core 611 are shown
inserted into, respectively lying in a first racket half 601. Said core components
can be compressible and can be inserted or mounted into said racket half 601 pre-loaded,
i.e. with an initial tension.
[0062] The main core 611 is partially wrapped up in a fabric component 605, which can cover
at least parts of the lateral surface 609 and at least parts of its two opposed surfaces
following at least in parts the shape of the two opposed striking surfaces (not shown)
of the racket, from which only surface 602 is visible here.
[0063] The handle core 607 can be for example completely wrapped in fabric component 606,
which can be the same or a different fabric component 605 than used for the main core
602.
[0064] Said fabric components 606, 605 may inter alia also be in parts glued to the corresponding
cores 607, 611 by curable resins, for example by heat-curable resins.
[0065] The average height 608 of the uncompressed handle core 607 and the average height
604 of the uncompressed main core 611 can be equal or different, for example height
the average height 608 of the uncompressed handle core 607 can be lower that the average
height 604 of the uncompressed main core 611. Both of said heights 608 and 604 can
equal or exceed the average height 603 of the sidewalls 610 of a racket half, i.e.
of racket half 601.
[0066] Said sidewalls 610 of racket half 601 may however vary in height and inclination
along the periphery of said racket half 601.
[0067] The with pre-loads in racket half 601 mountable and in fabric components 605, 606
wrapped core components 602, 611 can press said fabric components 605, 606 against
the inner surface of in racket half 601, in particular against the sidewalls 610 of
racket half 601, respectively the inner lateral surface 612 formed by said sidewalls
610.
[0068] Fig. 7a, Fig. 7b, and
Fig. 7c show exemplary profiles or cross sections 700, 800 and 900 of a racket according
to the invention along the line A to B from
Fig. 1.
[0069] Therein first main portions 701, 801, 901 and second main portions 702, 802, 902
of two racket halves joined along a plane 705, 805, 905 are shown, which comprise
first striking surface portions 703, 803, 903 and their opposing second striking surface
portions 704, 804, 904.
[0070] The difference between said exemplary cross sections 700, 800 and 900 of a racket
lies in the realization of their edge portions 706, 707, 806, 807, 906, 907.
[0071] In cross sections 700 and 800 the edge portions 706, 707, 806, 807 do not rise above
their corresponding striking surface portions 703, 704, 803, 804. However while edge
portions 706, 707 can form a straight lateral border 708, the edge portions 806, 807
can form a curved convex lateral border 808.
[0072] In cross section 900 the edge portions 906, 907 of the main portions 901, 902 can
form additional lateral sidewalls 909, 910 that rise above and delimit the striking
surface portions 903, 904. The lateral border 908 formed by the edge portions 906,
907 can be substantially straight (as shown) or can also have a convex or concave
curvature.
[0073] In addition the cross sections 700, 800 and 900 also show the core components or
main cores 709, 809 and 911, that fill out partially or completely the volume between
racket halves, respectively main portions 701, 702, 801, 802, 901, 902.
[0074] Obviously said cross sections 700, 800 and 900 are only examples and other cross
sections, including asymmetric cross sections with respect to planes 705, 805, and
905 are possible.
[0075] For completeness we note that all features described in the Figures and description
above can be combined, for example as previously noted a racket according to the invention
can also have through openings (not shown) that extend for example across the main
portions 701, 702, 801, 802, 901, 902 of a racket, respectively racket half.
[0076] The reference signs in Figs. 1, 2, 3, 4a, 4b, 5, 6, 7a, 7b, and 7c are denotes as
follows.
100 Racket for padel
101 First main portion
102 First handle portion
103 First striking surface portion
104 Peripheric edge portion or (generic) edge portion
105 Transition portion
106 Opening
107 Racket half
A, B Reference points for cut through the profile of the main portions of the racket halves
200 Racket for padel
201 First striking surface portion
202 Second striking surface portion
203 First racket half
204 Second racket half
205 First handle portion
206 Second handle portion
207 First edge portion
208 Second edge portion
209 First transition portion
210 Second transition portion
211 First main portion
212 Second main portion
213 Average thickness of racket across opposing striking surface portions
214 Average thickness of racket across opposing handle portions
215 Connection plane connecting first and second racket half
300 Racket half
301 Handle portion
302 Main portion
303 Striking surface
304 Sidewalls
305 Average height of sidewalls
306 Edge portion
307 End portion
308 Transition portion
401 Handle core
402 Handle core
403 Transition part
404 Transition part
500 Main core
501 Average thickness uncompressed of main core
502 Lateral surface of main core
503 Fabric component
504 Striking surface
600 Part of an exemplary internal structure of a racket
601 First racket half
602 Striking surface
603 Average height of sidewalls
604 Average height of uncompressed main core
605 Fabric component for main core
606 Fabric component for handle core
607 Handle core
608 Average height of uncompressed handle core
609 Lateral surface
610 Sidewalls
611 Main core
612 Inner lateral surface
700 Profile or cross section of a racket
701 First main portion
702 Second main portion
703 First striking surface
704 Second striking surface
705 Plane along which two racket halves are joined
706 First edge portion
707 Second edge portion
708 Lateral border
709 Core component or main core
800 Profile or cross section of a racket
801 First main portion
802 Second main portion
803 First striking surface
804 Second striking surface
805 Plane along which two racket halves are joined
806 First edge portion
807 Second edge portion
808 Lateral border
809 Core component or main core
900 Profile or cross section of a racket
901 First main portion
902 Second main portion
903 First striking surface
904 Second striking surface
905 Plane along which two racket halves are joined
906 First edge portion
907 Second edge portion
908 Lateral border
909 First additional lateral sidewall
910 Second additional lateral sidewall
911 Core component or main core
1. Racket (100, 200) for padel with two opposed striking surfaces, including a first
racket half (203) having a first handle portion (205) and a first main portion (211),
wherein said first main portion (211) comprises a first striking surface portion (201),
a second racket half (204) having a second handle portion (206) and a second main
portion, wherein said second main portion (212) comprises a second striking surface
portion (202), and at least one core component (500, 611) disposed between said racket
halves (203, 204), wherein said core component (500, 611) has two opposed surfaces
following at least in parts the shape of the two opposed striking surfaces of the
racket and a lateral surface (502, 609),
characterised in that,
the core component (500, 611) is compressible, and said core component (500, 611)
is wrapped up in a fabric component (605), wherein said fabric component (605) comprises
fibres and a cured resin and covers at least in parts the lateral surface (609) of
the core component (500, 611), and said core component (500, 611) is mounted with
a pre-load between the racket halves (203, 204), and said core component (500, 611)
is configured to press said fabric component (605) against the inner lateral surfaces
(612) of the first and the second racket half (203, 204), and wherein the fabric component
(605) bonds the first and second racket half (203, 204) together.
2. Racket (100, 200) according to claim 1, wherein the core component (500, 611) is made
of solid material or foam or comprises at least two material layers or has honey-comb
structure, or can be made of a combination of aforementioned material structures.
3. Racket (100, 200) according to any of the preceding claims, wherein the core component
is divided into two separate individual parts, a handle core part (607) and a main
core part (611), wherein the main core part (611), comprises two opposing striking
surface portions.
4. Racket (100, 200) according to claim 3, wherein the handle core part (607) is wrapped
up entirely in a fabric component (605), which comprises fibres and a cured resin.
5. Racket (100, 200) according to any of the preceding claims, wherein the racket halves
(203, 204) are unibodies.
6. Racket (100, 200) according to any of the preceding claims, wherein the main portion
(301, 701, 801, 901, 702, 802, 902) of a racket half has a substantially U-shaped
or pan-shaped profile, with the striking surface portion (703, 803, 903, 704, 804,
904) extending substantially flat between a peripheric edge portion (706, 707, 806,
807, 906, 907) of said main portion of a racket half.
7. Racket (100, 200) according to any of the preceding claims, wherein the main portion
of a racket half (901, 902) has a peripheric edge portion (906, 907), wherein said
edge portion forms lateral sidewalls (909, 910), which delimit the striking surface
portion (903, 904) of said main portion of a racket half.
8. Racket (100, 200) according to any of the preceding claims, wherein the core component
has an average uncompressed thickness (501) between 35 to 45 mm and/or wherein the
core component material comprises a polymeric foam or elastomeric foam, and for example
comprises ethylene vinyl acetate and/or polyurethane foam.
9. Method for producing a racket comprising the steps of:
coating the inner surface of a first racket half and a second racket half with a curable
resin,
wrapping a fabric component around a core component, covering at least the lateral
surface of the core component,
inserting the fabric wrapped core component into the first racket half under compression
of said core component, such that the core component is pre-loaded and presses the
fabric component against the inner lateral surface of the first racket half, mounting
the two racket halves containing the wrapped core component together, such that the
wrapped core component presses against the inner lateral surfaces of the first and
the second racket half, and
bonding the racket halves containing the wrapped core component together by bonding
means, such as for example by curing the resin by heating the two racket halves containing
the wrapped core component inside a racket mold.