Patents by Inventor Atsushi Kawakita
Atsushi Kawakita has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11660705Abstract: A laser welding method is provided to ensure a sufficient joining strength between metal plates by increasing the area of a joining region while preventing “burn through” of a molten metal. In the laser welding method by applying a laser beam to a surface of multiple metal plates superimposed on each other, a scanning locus with the laser beam is sequentially shifted from an inner circular scanning locus to an outer one in a predetermined joining region on the metal plates, and an emission interval is provided to temporally stop the metal-plate-surface irradiation when the scanning locus is shifted. Thus, every time the scanning locus is shifted, the molten metal due to the previous irradiation is cooled and increases its viscosity. Accordingly, the “burn through” is prevented regardless of increase of the area of the joining region, which results in a sufficient joining strength between the metal plates.Type: GrantFiled: April 24, 2019Date of Patent: May 30, 2023Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Koki Nakada, Toru Hioki, Atsushi Kawakita, Shuhei Ogura, Takashi Goto
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Patent number: 11511371Abstract: In a laser welding method, generation of relatively large blow holes in a welding part is prevented while decrease in productivity is reduced. The laser welding method for lap welding, using a laser beam LB, of a plurality of metal plates and including an aluminum alloy cast plate includes: a melting path of scanning and irradiating circularly a superimposed part of the aluminum alloy plate and the aluminum alloy cast plate with a first laser beam LB1 to form a molten pool of the molten aluminum alloy plate and the molten aluminum alloy cast plate; and a stirring path of scanning and irradiating circularly the molten pool with a second laser beam LB2 having a scanning speed V2 faster than a scanning speed V1 of the first laser beam LB1 to stir the molten pool.Type: GrantFiled: May 30, 2019Date of Patent: November 29, 2022Assignee: TOYOTA JTDOSHA KABUSHIKI KAISHAInventors: Toru Hioki, Shuhei Ogura, Atsushi Kawakita, Koki Nakada, Takashi Goto, Ryosuke Kawai
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Patent number: 11400540Abstract: An iron rivet including a head and a shank, an aluminum plate, an iron plate, and first and second electrodes are prepared. A sandwiching step of sandwiching the rivet, the aluminum plate, and the iron plate between the first electrode and the second electrode, a penetration step of performing pressurization and current application by the first and second electrodes so that the shank penetrates through the aluminum plate, and a forming step of performing pressurization and current application by the first and second electrodes so that a nugget is formed between the shank and the iron plate are included. In the penetration step, the pressurization and current application is performed while air is blown to a side face of the shank so that the air hits a region around a boundary between the shank and the aluminum plate.Type: GrantFiled: September 17, 2019Date of Patent: August 2, 2022Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Shotaro Kurokawa, Shuhei Ogura, Atsushi Kawakita, Keisuke Shinohara
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Patent number: 11247292Abstract: Provided are a method and an apparatus for resistance spot welding in which preliminary current application is executed and then main welding is executed in accordance with master patterns of various parameters obtained during the preliminary current application. The main welding is executed under welding conditions of the master patterns, and whether a welding abnormality has occurred and whether the welding abnormality is likely to occur are determined. When the welding abnormality is likely to occur, the welding conditions for the main welding are corrected so as to prevent the welding abnormality. When the welding abnormality is unlikely to occur, the welding conditions for the main welding are corrected so as to match the master patterns.Type: GrantFiled: March 6, 2019Date of Patent: February 15, 2022Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Koji Nomura, Shuhei Ogura, Atsushi Kawakita, Naoya Kato, Toru Hioki, Kenji Fukushima, Shun Kato, Takashi Goto
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Patent number: 11229976Abstract: Partial welding of partially joining together two metal plates by melting at least one area inside a joining region of the metal plates is performed. After a lapse of a predetermined time from completion of the partial welding, main welding of joining together the metal plates by melting the joining region entirely is performed.Type: GrantFiled: March 26, 2019Date of Patent: January 25, 2022Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Toru Hioki, Atsushi Kawakita, Shuhei Ogura, Ryosuke Kawai, Takashi Goto, Kazuho Takishita
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Patent number: 11135671Abstract: A resistance spot welding method includes sandwiching metal plates put on top of one another between a pair of electrodes and performing resistance spot welding sequentially on a plurality of welding points close to each other on the metal plates by performing a current application between the electrodes so as to join the metal plates to each other. A welding current value to form a welding nugget at a welding point to be subjected to the resistance spot welding second or later among the welding points is set to be higher than a first welding current value to form a first welding nugget at a first welding point to be subjected to the resistance spot welding first among the welding points.Type: GrantFiled: January 17, 2019Date of Patent: October 5, 2021Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Toru Hioki, Shuhei Ogura, Atsushi Kawakita, Yoichi Tsutsumi, Takashi Goto
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Patent number: 11084126Abstract: A laser welding method includes: forming a melted section in which plural metallic workpieces within a weld region are melted by projecting a first laser beam onto said weld region with parts of the workpieces being set as the weld region when the workpieces are welded; and projecting a second laser beam while the melted section is being solidified or after a solidified section in which the melted section is solidified is formed such that the second laser beam circles around center of the melted section or the solidified section from an irradiation start position deviated from said center toward said center or such that the second laser beam is focused to the center of the melted section or the solidified section from an irradiation start region that includes the center and a periphery thereof.Type: GrantFiled: October 18, 2018Date of Patent: August 10, 2021Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Kohei Hisada, Atsushi Kawakita, Masahiro Nakata
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Patent number: 10933459Abstract: A joining apparatus includes: a die having a recess; and a punch disposed opposite to the recess. The punch includes an inner punch portion and an outer punch portion disposed around the inner punch portion, the inner punch portion and outer punch portion are configured to be movable relative to each other, and a depression is formable at a front end of the punch. The joining apparatus is configured such that, in a state in which the depression is formed at the front end of the punch, the punch is moved relatively so as to press and deform the multiple plate members toward the recess by the punch, and the inner punch portion is moved relatively so as to extrude a metal in the depression by the inner punch portion.Type: GrantFiled: March 19, 2019Date of Patent: March 2, 2021Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Kohei Takahashi, Atsushi Kawakita, Junichiro Makino
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Patent number: 10786872Abstract: A welding method for integrally welding three or more superposed metal plates includes a spot welding of joining the first vehicle body structure plate and the second vehicle body structure plate by spot welding in a plurality of places along an opening edge of the door opening portion in a state where each of the metal plates is superposed, and a laser welding of joining the surface plate and the first vehicle body structure plate in a plurality of places including a place between welding places of the spot welding after the spot welding. The joining being performed by emitting laser light to the surface plate and by scanning the laser light to stir a molten pool including a molten metal of the surface plate and the first vehicle body structure plate melted by the laser light.Type: GrantFiled: June 13, 2018Date of Patent: September 29, 2020Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Atsushi Kawakita, Shuhei Ogura, Hiroki Sugino, Wataru Mizuno, Ryuta Matsuo
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Publication number: 20200130098Abstract: An iron rivet including a head and a shank, an aluminum plate, an iron plate, and first and second electrodes are prepared. A sandwiching step of sandwiching the rivet, the aluminum plate, and the iron plate between the first electrode and the second electrode, a penetration step of performing pressurization and current application by the first and second electrodes so that the shank penetrates through the aluminum plate, and a forming step of performing pressurization and current application by the first and second electrodes so that a nugget is formed between the shank and the iron plate are included. In the penetration step, the pressurization and current application is performed while air is blown to a side face of the shank so that the air hits a region around a boundary between the shank and the aluminum plate.Type: ApplicationFiled: September 17, 2019Publication date: April 30, 2020Applicant: Toyota Jidosha Kabushiki KaishaInventors: Shotaro Kurokawa, Shuhei Ogura, Atsushi Kawakita, Keisuke Shinohara
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Publication number: 20190366479Abstract: In a laser welding method, generation of relatively large blow holes in a welding part is prevented while decrease in productivity is reduced. The laser welding method for lap welding, using a laser beam LB, of a plurality of metal plates and including an aluminum alloy cast plate includes: a melting path of scanning and irradiating circularly a superimposed part of the aluminum alloy plate and the aluminum alloy cast plate with a first laser beam LB1 to form a molten pool of the molten aluminum alloy plate and the molten aluminum alloy cast plate; and a stirring path of scanning and irradiating circularly the molten pool with a second laser beam LB2 having a scanning speed V2 faster than a scanning speed V1 of the first laser beam LB1 to stir the molten pool.Type: ApplicationFiled: May 30, 2019Publication date: December 5, 2019Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Toru HIOKI, Shuhei OGURA, Atsushi KAWAKITA, Koki NAKADA, Takashi GOTO, Ryosuke KAWAI
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Publication number: 20190329361Abstract: A laser welding method is provided to ensure a sufficient joining strength between metal plates by increasing the area of a joining region while preventing “burn through” of a molten metal. In the laser welding method by applying a laser beam to a surface of multiple metal plates superimposed on each other, a scanning locus with the laser beam is sequentially shifted from an inner circular scanning locus to an outer one in a predetermined joining region on the metal plates, and an emission interval is provided to temporally stop the metal-plate-surface irradiation when the scanning locus is shifted. Thus, every time the scanning locus is shifted, the molten metal due to the previous irradiation is cooled and increases its viscosity. Accordingly, the “burn through” is prevented regardless of increase of the area of the joining region, which results in a sufficient joining strength between the metal plates.Type: ApplicationFiled: April 24, 2019Publication date: October 31, 2019Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Koki Nakada, Toru Hioki, Atsushi Kawakita, Shuhei Ogura, Takashi Goto
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Publication number: 20190308271Abstract: Partial welding of partially joining together two metal plates by melting at least one area inside a joining region of the metal plates is performed. After a lapse of a predetermined time from completion of the partial welding, main welding of joining together the metal plates by melting the joining region entirely is performed.Type: ApplicationFiled: March 26, 2019Publication date: October 10, 2019Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Toru HIOKI, Atsushi KAWAKITA, Shuhei OGURA, Ryosuke KAWAI, Takashi GOTO, Kazuho TAKISHITA
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Publication number: 20190291164Abstract: A joining apparatus includes: a die having a recess; and a punch disposed opposite to the recess. The punch includes an inner punch portion and an outer punch portion disposed around the inner punch portion, the inner punch portion and outer punch portion are configured to be movable relative to each other, and a depression is formable at a front end of the punch. The joining apparatus is configured such that, in a state in which the depression is formed at the front end of the punch, the punch is moved relatively so as to press and deform the multiple plate members toward the recess by the punch, and the inner punch portion is moved relatively so as to extrude a metal in the depression by the inner punch portion.Type: ApplicationFiled: March 19, 2019Publication date: September 26, 2019Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Kohei TAKAHASHI, Atsushi KAWAKITA, Junichiro MAKINO
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Publication number: 20190275606Abstract: Provided are a method and an apparatus for resistance spot welding in which preliminary current application is executed and then main welding is executed in accordance with master patterns of various parameters obtained during the preliminary current application. The main welding is executed under welding conditions of the master patterns, and whether a welding abnormality has occurred and whether the welding abnormality is likely to occur are determined. When the welding abnormality is likely to occur, the welding conditions for the main welding are corrected so as to prevent the welding abnormality. When the welding abnormality is unlikely to occur, the welding conditions for the main welding are corrected so as to match the master patterns.Type: ApplicationFiled: March 6, 2019Publication date: September 12, 2019Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Koji NOMURA, Shuhei OGURA, Atsushi KAWAKITA, Naoya KATO, Toru HIOKI, Kenji FUKUSHIMA, Shun KATO, Takashi GOTO
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Publication number: 20190247948Abstract: A resistance spot welding method includes sandwiching metal plates put on top of one another between a pair of electrodes and performing resistance spot welding sequentially on a plurality of welding points close to each other on the metal plates by performing a current application between the electrodes so as to join the metal plates to each other. A welding current value to form a welding nugget at a welding point to be subjected to the resistance spot welding second or later among the welding points is set to be higher than a first welding current value to form a first welding nugget at a first welding point to be subjected to the resistance spot welding first among the welding points.Type: ApplicationFiled: January 17, 2019Publication date: August 15, 2019Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Toru HIOKI, Shuhei Ogura, Atsushi Kawakita, Yoichi Tsutsumi, Takashi Goto
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Publication number: 20190070695Abstract: A laser welding method includes: forming a melted section in which plural metallic workpieces within a weld region are melted by projecting a first laser beam onto said weld region with parts of the workpieces being set as the weld region when the workpieces are welded; and projecting a second laser beam while the melted section is being solidified or after a solidified section in which the melted section is solidified is formed such that the second laser beam circles around center of the melted section or the solidified section from an irradiation start position deviated from said center toward said center or such that the second laser beam is focused to the center of the melted section or the solidified section from an irradiation start region that includes the center and a periphery thereof.Type: ApplicationFiled: October 18, 2018Publication date: March 7, 2019Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Kohei HISADA, Atsushi KAWAKITA, Masahiro NAKATA
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Publication number: 20180361508Abstract: A welding method for integrally welding three or more superposed metal plates includes a spot welding of joining the first vehicle body structure plate and the second vehicle body structure plate by spot welding in a plurality of places along an opening edge of the door opening portion in a state where each of the metal plates is superposed, and a laser welding of joining the surface plate and the first vehicle body structure plate in a plurality of places including a place between welding places of the spot welding after the spot welding. The joining being performed by emitting laser light to the surface plate and by scanning the laser light to stir a molten pool including a molten metal of the surface plate and the first vehicle body structure plate melted by the laser light.Type: ApplicationFiled: June 13, 2018Publication date: December 20, 2018Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Atsushi KAWAKITA, Shuhei OGURA, Hiroki SUGINO, Wataru MIZUNO, Ryuta MATSUO
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Patent number: 10144089Abstract: A laser processing apparatus includes: a head main body housing an optical system; and a nozzle that is fastened to the head main body by thread fastening and that applies the laser beam to a workpiece. The nozzle has a nozzle hole through which the laser beam passes. A pressure chamber is formed between the head main body and the nozzle. The pressure chamber is a space surrounded by a bottom surface of the head main body, the bottom surface intersecting with a fastening direction in which the head main body and the nozzle are fastened together by thread fastening, and a bottom surface of the nozzle, the bottom surface intersecting with the fastening direction. The pressure chamber is supplied with air or assist gas. The nozzle has a communication hole that provides communication between the pressure chamber and the nozzle hole.Type: GrantFiled: January 14, 2015Date of Patent: December 4, 2018Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Kohei Hisada, Atsushi Kawakita
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Patent number: 10137530Abstract: A laser welding method includes: forming a melted section in which plural metallic workpieces within a weld region are melted by projecting a first laser beam onto said weld region with parts of the workpieces being set as the weld region when the workpieces are welded; and projecting a second laser beam while the melted section is being solidified or after a solidified section in which the melted section is solidified is formed such that the second laser beam circles around center of the melted section or the solidified section from an irradiation start position deviated from said center toward said center or such that the second laser beam is focused to the center of the melted section or the solidified section from an irradiation start region that includes the center and a periphery thereof.Type: GrantFiled: April 7, 2015Date of Patent: November 27, 2018Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Kohei Hisada, Atsushi Kawakita, Masahiro Nakata