Inflatable sportsball with cushion layer

Information

  • Patent Grant
  • 6506135
  • Patent Number
    6,506,135
  • Date Filed
    Monday, January 22, 2001
    24 years ago
  • Date Issued
    Tuesday, January 14, 2003
    22 years ago
Abstract
An inflatable sportsball with cushion layer includes an inflatable ball carcass defining a shape of the sportsball and a ball cover for covering the ball carcass to provide uniform softness and roundness. The ball carcass is an integral hollow ball body, which includes an inner inflatable rubber bladder, a winding thread layer that surrounds the rubber bladder with a reinforcing thread, an outer rubber layer surrounding the winding thread layer in such a manner that the outer rubber layer, the winding thread layer and the rubber bladder are integrally fused into a single fusion layer, wherein the ball carcass further includes a plurality of seam channels integrally and spacedly raised from an outer surface thereof and panels of foaming layer which are positioned between the seam channels and sandwiched between the outer rubber layer and the inner rubber layer fused on top of the winding thread layer.
Description




BACKGROUND OF THE PRESENT INVENTION




1. Field of Invention




The present invention relates to an inflatable sportsball, and more particularly to an inflatable sportsball having a cushioned carcass by constructing a cushion layer therein so as to increase the softness of the sportsball and enhancing the roundness of the sportsball.




2. Description of Related Arts




Sportsballs, such as basketballs, soccer balls, and footballs conventionally comprise an inflatable bladder and a cover. The inflatable bladder is disposed within the ball cover for propping up the ball after inflation. The inflatable bladder can be made of rubber or polyurethane that can be reinforced with windings of nylon thread or polyester thread. The ball cover generally comprises a carcass and panels made of rubber, synthetic leather or leather, wherein adjacent panels are separated by rubber channels.




In order to improve a player's ability of gripping the sportsball and to reduce the shock of impact, the carcass of the sportsball is made to include cushion layers, such as panels of sponge rubber, which are directly adhered on the carcass between the rubber channels. However, the cover panels which cover the cushion layers do not adhere well to the cushion layers. The cover panels also have a tendency to peel away from the additional cushion layers.




U.S. Pat. No. 5,636,835 suggests that after the winding thread layer is attached to the bladder, panels of foamable rubber layer are attached to the winding thread layer. The foamable rubber layers are made from a type of rubber designed to foam and create cellular sponge rubber upon application of heat. Consequently, the foamable rubber layers stick directly on the winding thread layer and hold their positions prior to placement in a mold. Then, seam channels of unformed seam material are placed over the discontinuities between individual panels of foamable rubber layer, i.e. a rubber layer containing foaming agent.




After the foamable rubber layers and unformed seam channels are in position, the entire arrangement is placed into a carcass-forming mold. In the mold, the carcass is cured under heat in the same way of the conventional ball carcass. The heat causes the foaming agent within the foamable rubber to expand and the panels of foamable rubber layer forms a single, uniform cellular sponge layer. The thickness of which is dependent on the space between the outer diameter of the winding thread layer and the inner diameter of the mold and the amount of the out gate created by the foaming agent. The seam channels are molded at the same time, thereby creating the raised seams familiar to conventional basketballs. The sponge layer, which is substantially and directly surrounding the layer of winding, directly underlies the raised seams. The inner carcass portion, cellular sponge layer and raised seams together define the ball carcass.




U.S. Pat. No. 5,681,233 suggests that the bladder is inflated and placed in a vulcanizing or curing mold where the bladder is cured by heating. After curing, the inflated bladder is wound with reinforcing thread. Flat sheets or panels of sponge rubber are laid on the wound bladder. The panels of sponge rubber are arranged so that a gap of about 5 mm separates adjacent panels to form a carcass. The carcass is placed in a spherical mold, and the inflated carcass is heat molded at 160° C. During the molding process, a foaming agent in the sponge rubber foams and creates a cellular structure in the foam rubber, which also bonds to the wound bladder, so as to form the ball carcass.




In view of the above conventional arts, a special type of foamable rubber, which is designed to foam, is used to directly stick on the winding thread layer of the inner carcass, wherein such foamable rubber reacts to create the cellular sponge rubber upon application of heat within a kind of close type mold. Therefore, the conventional cushioned inflatable ball generally comprises an inflatable bladder and a layer of winding covering the bladder to form an inner carcass defining the shape of the ball, a cellular sponge rubber layer surrounding the inner carcass, and a cover layer surrounding the sponge rubber layer. The cellular sponge rubber layer is formed upon the application of heat within a close type mold, wherein the foamable rubber releases gas upon application of heat to produce a plurality of air meshes and increase the thickness of the rubber to form the cellular sponge rubber so as to achieve the softness feel and effect.




However, there are some drawbacks of the conventional cushioned inflatable balls. Since the foaming process of the sponge rubber is processed in a closed state, that is the foamable rubber is heated inside the press mold in an air tight manner, the gas released from the foamable rubber has no where to escape and no way to be evenly distributed during foaming between the interior surface of the mold and the inner carcass. In other words, it is very difficult to obtain a cellular sponge rubber layer with even thickness. Moreover, the released gas will inwardly press against the inner carcass and force the winding thread to separate from the inflatable blabber, that may affect the roundness of the inflatable ball.




According to both U.S. Pat. Nos. 5,636,835 and 5,681,233, the foaming reaction of the foamable rubber within the close type mold cannot be completely controlled such that the sponge rubber after reaction may not have a uniform thickness, which may affect the softness and the stiffness of the ball. Practically, the conventional cushioned carcass structure provides a great headache to most of the ball manufacturers, that is why a large number of manufactured balls will fail the quality test and become defective goods. It not only increases the manufacturing cost unreasonably but also adversely affects the softness and gripping feel of the balls.




Furthermore, in the U.S. Pat. No. 5,636,835, the thickness of the raised channels is reduced by the underlying uniform cellular sponge layer, so that the raised channels are easier worn out that shortens the life span of the ball.




Also, in order to fit different types of playground and different ages of players, different types of sportsball with different levels of softness and stiffness must be made. For example, the sportsball for junior players may have softer ball carcass and the sportsball for professional players may have stiffer ball carcass.




SUMMARY OF THE PRESENT INVENTION




A main object of the present invention is to provide an inflatable sportsball which is integrally constructed with a plurality of cushioned portions between the seam channels so as to provide uniform cushion softness for the sportsball.




Another object of the present invention is to provide an inflatable sportsball with cushion layer, which has a softer feeling to reduce the painful during ball passing and catching, especially suitable for children, training players and amateur players.




Another object of the present invention is to provide an inflatable sportsball with cushion layer which can reduce the impact force between the player and the sportsball, so as to prevent an unwanted injure of the player hit by the impact force while receiving the sportsball. Thus, the cushion layer tolerates more impact on the sportsball so as to retain the shape of the sportsball.




Another object of the present invention is to provide a method of manufacturing an inflatable sportsball, which can manufacture a cushioned sportsball in an efficient and economic way and effectively control the softness and roundness of the sportsball.




Another object of the present invention is to provide a method of manufacturing an inflatable sportsball with cushion layer, which can adjust the softness of the sportsball easily. Also, the manufacturing method enables the cushion layers of the sportsball made having a uniform thickness so as to enhance the roundness of the sportsball.




Accordingly, in order to accomplish the above objects, the present invention provides an inflatable sportsball which comprises:




an inflatable ball carcass defining a shape of the sportsball, wherein the ball carcass is an integral hollow ball body, which includes an inner inflatable rubber bladder, a winding thread layer that surrounds the rubber bladder with a reinforcing thread, an outer rubber layer surrounding the winding thread layer in such a manner that the outer rubber layer, the winding thread layer and the rubber bladder are integrally fused into a single fusion layer, wherein the ball carcass further includes a plurality of seam channels integrally and spacedly raised from an outer surface thereof and panels of foaming layer which are positioned between the seam channels and sandwiched between the outer rubber layer and the inner rubber layer fused on top of the winding thread layer; and




a ball cover for covering the ball carcass, wherein the ball cover comprises a plurality of skin panels attached to the outer surface of the ball carcass between the seam channels.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a partial exploded perspective view of an inflatable sportsball according to a preferred embodiment of the present invention.





FIG. 2

is a schematic view illustrating the two manufacturing steps of an inner carcass of the inflatable sportsball according to the above preferred embodiment of the present invention.





FIG. 3A

is a partial sectional view of the inner carcass of the inflatable sportsball according to the above preferred embodiment of the present invention.





FIG. 3B

is a partial sectional view of the inner carcass having panels of cushion layer and rubber strip attached thereon according to the above preferred embodiment of the present invention.





FIG. 3C

is a partial sectional view of a semi-finished ball carcass of the inflatable sportsball according to the above preferred embodiment of the present invention.





FIG. 4

is a perspective of the semi-finished ball carcass of the inflatable sportsball according to the above preferred embodiment of the present invention.





FIG. 5

is a partial sectional view of a ball carcass of the inflatable sportsball according to the above preferred embodiment of the present invention.





FIG. 6

is a partial sectional view of the inflatable sportsball according to the above preferred embodiment of the present invention.





FIG. 7

is a perspective view illustrating the formation of the cushion layers and rubber strips according to the above preferred embodiment of the present invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




Referring to

FIG. 1

of the drawings, the present invention provides an inflatable sportsball which comprises an inflatable ball carcass


10


defining a shape of the sportsball and a ball cover


20


for covering the ball carcass


10


, wherein the ball cover


20


comprises a plurality of skin panels


21


attached to the outer surface of the ball carcass


10


between the seam channels


15


.




Referring to

FIGS. 2

to


4


, according to the preferred embodiment of the present invention, the sportsball is embodied as a basketball, wherein the ball carcass


10


is a cushioned ball carcass manufacturing by an innovative method.




As shown in

FIGS. 2 and 3A

, in order to make the ball carcass


10


, an inflatable


15


rubber bladder


11


is inflated through a valve stem


111


provided thereon. The inflated rubber bladder


11


is wound with reinforcing thread


121


, such as nylon thread, which forms a winding thread layer


12


surrounding the rubber bladder


11


so as to form an inner carcass


100


.




As shown in

FIG. 7

, a plurality of cushion panels


13


are provided by cutting from a large piece of laminated cushion layer


130


which comprises a thin inner rubber layer


131


, a foaming layer


132


firmly adhered on the inner rubber layer


131


, and a thin outer rubber layer


133


firmly adhered on the foaming layer


132


. The inner rubber layer


131


and the outer rubber layer


133


are preferred to have a thickness of less than 1 mm and the foaming layer


132


is preferred to have a thickness of 1 mm to 2 mm. The foaming layer


132


is made of foaming material such as EVA and sponge rubber which is made by heating a kind of rubber contained foaming agent inside a mold. In order words, the cushion panel


13


contains no foaming agent and will not generate gas upon heating.




When sponge rubber is used as the foaming material, the manufacturer will first to adhere the inner rubber layer


131


and the outer rubber layer


133


on both side surfaces of a foaming rubber


132


containing foaming agent. Then, the foaming rubber


132


with the inner and outer rubber layers


131


,


133


adhered thereon are placed in a plate mold and heated to a predetermined temperature. When the plate mold is opened, the gas released during the foaming process emits to the air so as to produce the foaming layer


132


with a uniform thickness and even softness.




Each of the cushion panels


13


is cut to a predetermined shape. The cushion panels


13


are adhered on the winding thread layer


12


of the inner carcass


100


and arranged to form a gap 140 of 10 mm to 15 mm to separate adjacent cushion panels


13


, as shown in FIG.


3


B.




As shown in

FIGS. 7 and 3B

, a plurality of rubber strips


14


each has a predetermined width fittingly to fill the gap


140


separating adjacent cushion panels


13


and a thickness thinner than the cushion panel


13


, i.e. about 1 mm. In other words, each rubber strip


14


, which is made of general rubber material containing no foaming agent, is thicker than the inner rubber layer


131


of the cushion panel


13


. The rubber strips


14


are adhered along the gaps


140


formed between the sides of the cushion panels


13


. So that, as shown in

FIG. 3B

, all the cushion panels


13


and the rubber strips


14


are arranged edge by edge to completely cover the inner carcass


100


.




As shown in

FIGS. 3C and 4

, an elongated rubber film


141


has a thin thickness thinner than the outer rubber layer


133


of the cushion panel


13


and a width wider than the gap


140


and the rubber strips


14


. The rubber film


141


is adhered along the rubber strips


14


, wherein two side edges of the rubber film


141


are arranged to stick along the side portions of the two adjacent cushion panels


13


respectively so as to completely cover any possible clearance occurred between the rubber strip


14


and the adjacent cushion panels


13


. Therefore, a semi-finished ball carcass


101


is formed, as shown in FIG.


4


.




In order to better shape the roundness of the sportsball, an additional strip of rubber film


142


is preferred to stick around the semi-finished ball carcass


101


in such a manner that the rubber film


142


can extend across all the rubber strips


14


.




The semi-finished ball carcass


101


is then placed in a spherical mold and the inflated semi-finished ball carcass


101


is heat molded to a predetermined temperature, such as 160° C. During the molding process, under each of the cushion panels


13


, the inner rubber layer


131


of the cushion panel


13


melts into the winding threads


121


of the winding thread layer


12


and fuses to the rubber bladder


11


integrally, as shown in FIG.


5


. Moreover, along the rubber strips


14


, the rubber film


142


, the rubber strips


14


, and the inner rubber layers


131


of the adjacent cushion panels


13


melt into the winding threads


121


of the winding thread layer


12


and fuse to the rubber bladder


11


to form the ball carcass


10


as shown in FIG.


1


.




Accordingly, referring to

FIGS. 1 and 5

, after the heat molding process, the semi-finished ball carcass


101


is fused into an integral hollow ball body to form the inflatable ball carcass


10


. In other words, all the rubber materials, including the rubber film


142


, the rubber strips


14


, the inner rubber layers


131


, and the outer rubber layers


133


are fused into a single fusion layer of the ball carcass


10


. According to the preferred embodiment, in order to produce a basketball as the sportsball, along the gaps


14


positioned between the cushion panels


13


, no foaming material is contained. The mold is designed to fuse and shape the rubber strips


14


into the plurality of seam channels


15


integrally and spacedly raised from an outer surface of the ball carcass


10


. At the same time, as shown in

FIG. 5

, the foaming layer


132


of each of the cushion panels


13


is embedded in the ball carcass


10


to form a plurality of foaming panels


132


A sandwiched between the outer rubber layer


133


and the winding thread layer


12


and positioned between the seam channels


15


. Therefore, the portions spaced between the seam channels


15


become cushioned carcass portions


16


that provide the softness feel of the sportsball, improve a player's ability to grip the sportsball and reduce the shock of impact.




As shown in

FIGS. 5 and 6

, along both sides of each of the seam channels


15


, indention grooves


151


are formed to provide the pop-up shape of the cushioned carcass portions


16


. Finally, as shown in

FIG. 6

, the skin panels


21


are adhered on the cushioned carcass portions


16


respectively to form the sportsball.




In view of above, the inflatable sportsball according to the present invention can achieve the following advantages:




(a) The even softness and uniform thickness of the foaming layers


132


provide a better soft feel to grip. Moreover, the manufacturer can control the softness of the sportsball simply by adjusting the thickness of the foaming layer


132


of the cushion panel


13


.




(b) Since there is no gas released during the heat molding process of the sportsball, the problem of inverse gas pressure that may separate the winding thread from the bladder can thus be eliminated.




(c) The integral structure provides a durable construction for the sportsball that can better resist impact. Moreover, no foaming material underlies the seam channels to prevent the conventional problem of that the seam channels are easy worn out.




(d) The manufacturing process is simple and efficient because no calculation or measurement of the amount of gas will be released during the heat molding process.




(e) For the ball carcass, the cushioned carcass portions are raised higher than the seam channels, which enable the players' ability of gripping the sportsball easily and firmly.



Claims
  • 1. A method of manufacturing an inflatable sportsball, comprising the steps of:(a) winding an inflated rubber bladder with reinforcing thread to form a winding thread layer surrounding said rubber bladder so as to form an inner carcass; (b) providing a plurality of cushion panels each having a predetermined shape and thickness, wherein each of said cushion panels comprises a thin inner rubber layer, a foaming layer firmly adhered on said inner rubber layer, and a thin outer rubber layer firmly adhered on said foaming layer; (c) adhering said cushion panels on said winding thread layer of said inner carcass and arranged to define a gap separating said two adjacent cushion panels; (d) providing a plurality of rubber strips each has a predetermined width fittingly to fill said gaps between said cushion panels and a thickness thinner than said cushion panel; (e) filling said rubber strips in said gaps and adhering said rubber strips on said winding thread layer of said inner carcass between said cushion panels until said inner carcass is completely covered by said cushion panels and said rubber strips to form a semi-finished ball carcass; (f) heat molding said inflated semi-finished ball carcass until all rubber materials, including said rubber bladder, said inner rubber layers of said cushion panels, said rubber strips, and said outer rubber layers of said cushion panels, are melted into a single fusion layer and said semi-finished ball carcass is fused into an integral hollow ball body to form an inflatable ball carcass, wherein said rubber strips are molded to form a plurality of seam channels raised from an outer surface of said inflatable ball carcass and said foaming layers of said cushion panels are embedded in said inflatable ball carcass to form a plurality of foaming panels sandwiched between said outer rubber layer and said winding thread layer and positioned between said seam channels, so that portions spaced between said seam channels become cushioned carcass portions; and (g) attaching a plurality of skin panels on said cushioned carcass portions respectively to form said inflatable sportsball.
  • 2. The method as recited in claim 1, after the step (e), further comprising a step of adhering strips of elongated rubber films along said rubber strips, wherein each of said rubber film having a width wider than said gap and said rubber strips, and thus two side edges of each of said rubber films are arranged to stick along side portions of said two adjacent cushion panels.
  • 3. The method as recited in claim 2, before the step (f), further comprising a step of providing an additional strip of rubber film to stick around said semi-finished ball carcass in such a manner that said rubber film extends across all said rubber strips.
  • 4. The method as recited in claim 2 wherein, in the step (f), under each of said cushion panels, said inner rubber layer of said cushion panel melts into said winding threads of said winding thread layer and fuses to said rubber bladder integrally, and that along each of said rubber strips, said rubber film, said rubber strips, and said inner rubber layers of said adjacent cushion panels melt into said winding threads of said winding thread layer and fuse to said rubber bladder to form said ball carcass.
  • 5. The method as recited in claim 3 wherein, in the step (f), under each of said cushion panels, said inner rubber layer of said cushion panel melts into said winding threads of said winding thread layer and fuses to said rubber bladder integrally, and that along each of said rubber strips, said rubber film, said rubber strips, and said inner rubber layers of said adjacent cushion panels melt into said winding threads of said winding thread layer and fuse to said rubber bladder to form said ball carcass.
  • 6. The method as recited in claim 1 wherein said inner rubber layer and said outer rubber layer have a thickness of less than 1 mm and said foaming layer has a thickness of 1 mm to 2 mm.
  • 7. The method as recited in claim 2 wherein said inner rubber layer and said outer rubber layer have a thickness of less than 1 mm and said foaming layer has a thickness of 1 mm to 2 mm.
  • 8. The method as recited in claim 4 wherein said inner rubber layer and said outer rubber layer have a thickness of less than 1 mm and said foaming layer has a thickness of 1 mm to 2 mm.
  • 9. The method as recited in claim 1 wherein, in the step (b), said foaming layer is made of sponge rubber which is made by heating a kind of rubber contained foaming agent inside a mold.
  • 10. The method as recited in claim 2 wherein, in the step (b), said foaming layer is made of sponge rubber which is made by heating a kind of rubber contained foaming agent inside a mold.
  • 11. The method as recited in claim 4 wherein, in the step (b), said foaming layer is made of sponge rubber which is made by heating a kind of rubber contained foaming agent inside a mold.
  • 12. The method as recited in claim 9 wherein said sponge rubber is made by adhering said inner rubber layer and said outer rubber layer on both side surfaces of a foaming rubber containing a foaming agent, and then heating said foaming rubber with said inner and outer rubber layers adhered thereon in a plate mold until gas is released from said foaming rubber to produce air meshes and increase thickness to form said sponge rubber with uniform thickness and even softness.
  • 13. The method as recited in claim 11 wherein said sponge rubber is made by adhering said inner rubber layer and said outer rubber layer on both side surfaces of a foaming rubber containing a foaming agent, and then heating said foaming rubber with said inner and outer rubber layers adhered thereon in a plate mold until gas is released from said foaming rubber to produce air meshes and increase thickness to form said sponge rubber with uniform thickness and even softness.
  • 14. The method as recited in claim 1 wherein a width of each of said gap is between 10 mm to 15 mm.
US Referenced Citations (6)
Number Name Date Kind
3508750 Henderson Apr 1970 A
5681233 Guenther et al. Oct 1997 A
5931752 Guenther et al. Aug 1999 A
6022283 Schindler et al. Feb 2000 A
6099423 Ou Aug 2000 A
6206795 Ou Mar 2001 B1