# US 10,369,422 B2 · Badminton racket > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,369,422 B2 - Document ID: US10369422B2 - Status: Granted - Kind: B2 - Application number: 15/577,982 - Filed: 2016-06-02 - Published: 2018-10-11 - Granted: 2019-08-06 - Earliest claimed: 2015-06-05 - Assignees: Yonex Kabushiki Kaisha - Applicants: Yonex Co., Ltd. - Inventors: Yosuke Yamanaka; Kazuya Otani; Taketoshi Goto - Web page: https://patentgrep.com/patent/US10369422B2 ## CPC - A63B 49/02: Frames - A63B 60/10: with means for indicating correct holding positions (A63B60/12 takes precedence) - A63B 2071/0694: {Visual indication, e.g. Indicia} - A63B 2102/04: Badminton - A63B 2209/02: with reinforcing fibres, e.g. carbon, polyamide fibres - A63B: APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT (apparatus for passive exercising, massage A61H) ## Abstract An object is to provide a badminton racket capable of easily achieving different performance properties on both sides of the hitting surface easily. A racket includes a frame which extends annularly, a grip, and a string which is stretched across the frame to form a hitting surface on both sides of the frame. The frame is formed to make the front surface portion and the back surface portion thereof asymmetrical in shape in a cross sectional view taken along a plane orthogonal to the extension direction of the frame. The formation of the frame into such an asymmetrical shape makes it possible to change performance properties on shuttlecock hitting between the front and back sides of the hitting surface at the time of hitting the shuttlecock, thus making it possible for the player to obtain two difference capabilities with the single racket simply by changing his or her grip. ## Claims ### Claim 1 A badminton racket comprising: a frame which extends annularly, a grip, a shaft which connects said frame and said grip to each other, and a string which is stretched across said frame to form a hitting surface on both sides of said frame, said frame is formed to make a front surface portion and a back surface portion thereof asymmetrical in shape in a cross sectional view taken along a plane orthogonal to an extension direction of said frame; wherein at least one of said frame and said shaft comprises a first colored portion and a second colored portion for distinguishing between front and back sides of said hitting surface, and wherein, as said badminton racket is viewed from a certain angle in a direction nonparallel and non-orthogonal to said hitting surface, said first colored portion appears visible while said second colored portion is hidden from view, and flipping said hitting surface from this state causes said second colored portion to appear visible and causes said first colored portion to be hidden from view. ### Claim 2 (depends on 1) The badminton racket according to claim 1, wherein a through-hole into which said string is inserted is formed in said frame, and wherein said front surface portion and said back surface portion are mutually different in protruding amount in a frontward/backward direction with respect to a position of a central axis of said insertion hole. ### Claim 3 (depends on 1) The badminton racket according to claim 1, wherein one of said front surface portion and said back surface portion comprises a flat surface portion substantially parallel to an in-plane direction of said hitting surface, and wherein the other of said front surface portion and said back surface portion comprises a curved surface portion which bulges in a frontward/backward direction. ### Claim 4 (depends on 1) The badminton racket according to claim 1, wherein said frame comprises a front-surface forming body which forms said front surface portion and a back-surface forming body which forms said back surface portion, and wherein one of said front-surface forming body and said back-surface forming body is formed to include a material different from a material of the other of said front-surface forming body and said back-surface forming body. ### Claim 5 (depends on 2) The badminton racket according to claim 2, wherein one of said front surface portion and said back surface portion comprises a flat surface portion substantially parallel to an in-plane direction of said hitting surface, and wherein the other of said front surface portion and said back surface portion comprises a curved surface portion which bulges in a frontward/backward direction. ### Claim 6 (depends on 5) The badminton racket according to claim 5, wherein said frame comprises a front-surface forming body which forms said front surface portion and a back-surface forming body which forms said back surface portion, and wherein one of said front-surface forming body and said back-surface forming body is formed to include a material different from a material of the other of said front-surface forming body and said back-surface forming body. ### Claim 7 A badminton racket comprising: a frame which extends annularly, a grip, a shaft which connects said frame and said grip to each other, and a string which is stretched across said frame to form a hitting surface on both sides of said frame, said frame is formed to make a front surface portion and a back surface portion thereof asymmetrical in shape in a cross sectional view taken along a plane orthogonal to an extension direction of said frame; wherein a through-hole into which said string is inserted is formed in said frame, and wherein said front surface portion and said back surface portion are mutually different in protruding amount in a frontward/backward direction with respect to a position of a central axis of said insertion hole, wherein said frame comprises a front-surface forming body which forms said front surface portion and a back-surface forming body which forms said back surface portion, and wherein one of said front-surface forming body and said back-surface forming body is formed to include a material different from a material of the other of said front-surface forming body and said back-surface forming body. ### Claim 8 (depends on 7) The badminton racket according to claim 7, wherein at least one of said frame and said shaft comprises a first colored portion and a second colored portion for distinguishing between front and back sides of said hitting surface, and wherein, as said badminton racket is viewed from a certain angle in a direction nonparallel and non-orthogonal to said hitting surface, said first colored portion appears visible while said second colored portion is hidden from view, and flipping said hitting surface from this state causes said second colored portion to appear visible and causes said first colored portion to be hidden from view. ### Claim 9 A badminton racket comprising: a frame which extends annularly, a grip, a shaft which connects said frame and said grip to each other, and a string which is stretched across said frame to form a hitting surface on both sides of said frame, said frame is formed to make a front surface portion and a back surface portion thereof asymmetrical in shape in a cross sectional view taken along a plane orthogonal to an extension direction of said frame; wherein one of said front surface portion and said back surface portion comprises a flat surface portion substantially parallel to an in-plane direction of said hitting surface, and wherein the other of said front surface portion and said back surface portion comprises a curved surface portion which bulges in a frontward/backward direction, wherein said frame comprises a front-surface forming body which forms said front surface portion and a back-surface forming body which forms said back surface portion, and wherein one of said front-surface forming body and said back-surface forming body is formed to include a material different from a material of the other of said front-surface forming body and said back-surface forming body. ### Claim 10 (depends on 9) The badminton racket according to claim 9, wherein at least one of said frame and said shaft comprises a first colored portion and a second colored portion for distinguishing between front and back sides of said hitting surface, and wherein, as said badminton racket is viewed from a certain angle in a direction nonparallel and non-orthogonal to said hitting surface, said first colored portion appears visible while said second colored portion is hidden from view, and flipping said hitting surface from this state causes said second colored portion to appear visible and causes said first colored portion to be hidden from view.