US 12,240,312 B2
Tray and tray manufacturing method
Hiromi Asama, Tokyo (JP); and Junichiro Suzuki, Tokyo (JP)
Assigned to NIPPON STEEL CORPORATION, Tokyo (JP)
Appl. No. 17/783,508
Filed by NIPPON STEEL CORPORATION, Tokyo (JP)
PCT Filed Feb. 4, 2021, PCT No. PCT/JP2021/004074
§ 371(c)(1), (2) Date Jun. 8, 2022,
PCT Pub. No. WO2021/157648, PCT Pub. Date Aug. 12, 2021.
Claims priority of application No. 2020-017224 (JP), filed on Feb. 4, 2020.
Prior Publication US 2022/0388386 A1, Dec. 8, 2022
Int. Cl. B60K 1/04 (2019.01); B62D 21/15 (2006.01); B62D 25/20 (2006.01); H01M 50/20 (2021.01)
CPC B60K 1/04 (2013.01) [B62D 21/15 (2013.01); B62D 25/20 (2013.01); H01M 50/20 (2021.01); B60K 2001/0438 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A tray including a bottom wall and a peripheral side wall erected from an outer periphery of the bottom wall, the tray comprising:
a high-strength portion having a high tensile strength; and
a low-strength portion having a tensile strength lower than that of the high-strength portion,
wherein the peripheral side wall includes a first side wall, a second side wall, a third side wall and a four side wall,
wherein the tray is quadrilateral including the first side wall, the second side wall, the third side wall, and the fourth side wall,
wherein the low-strength portion is formed in a region including a first recessed portion having:
a first corner portion in a first side wall inner surface of the first side wall and a second side wall inner surface of the second side wall which are adjacent to each other at a minor angle, and
a first corner section on an upper surface of the bottom wall having a minor angle to each of the first side wall inner surface and the second side wall inner surface in the first corner portion,
wherein the low-strength portion is further formed in a region including a second recessed portion having:
a second corner portion in the second side wall inner surface of the second side wall and a third side wall inner surface of the fourth side wall which are adjacent to each other at a minor angle, and
a second corner section on an upper surface of the bottom wall having a minor angle to each of the second side wall inner surface and the third side wall inner surface in the second corner portion,
wherein the low-strength portion is formed in a region including a third recessed portion having:
a third corner portion in a third side wall inner surface of the third side wall and the fourth side wall inner surface of the fourth side wall which are adjacent to each other at a minor angle, and
a third corner section on an upper surface of the bottom wall having a minor angle to each of the third side wall inner surface and the fourth side wall inner surface in the third corner portion,
wherein the low-strength portion is further formed in a region including a fourth recessed portion having:
a fourth corner portion in the fourth side wall inner surface of the fourth side wall and the first side wall inner surface of the first side wall which are adjacent to each other at a minor angle, and
a fourth corner section on an upper surface of the bottom wall having a minor angle to each of the fourth side wall inner surface and the first side wall inner surface in the fourth corner portion, and
wherein the high-strength portion is formed from the first side wall to the third side wall facing the first side wall via the bottom wall.