US 11,986,876 B1
Pipe expanding head, pipe expanding head assembly and pipe expanding plier
Xiaoming Deng, Zhuji (CN); and Jiulian Xu, Zhuji (CN)
Assigned to Zhuji ITOP Hardware Tools Co., Ltd., Zhuji (CN)
Filed by Zhuji ITOP Hardware Tools Co., Ltd., Zhuji (CN)
Filed on Sep. 29, 2023, as Appl. No. 18/478,859.
Claims priority of application No. 202320476328.5 (CN), filed on Mar. 14, 2023.
Int. Cl. B21D 41/02 (2006.01)
CPC B21D 41/021 (2013.01) 20 Claims
OG exemplary drawing
 
1. A pipe expanding head, comprising pipe expanding pieces which are circumferentially distributed along a direction of a central axis, wherein the pipe expanding pieces each comprises a first external tooth arc part, a first joint arc part, a second external tooth arc part, a second joint arc part and a positioning part which are sequentially arranged along the direction of the central axis of the pipe expanding head, outer surfaces of the first external tooth arc part and the first joint arc part being in a same arc surface, and outer surfaces of the second external tooth arc part and the second joint arc part being in a same arc surface; and the pipe expanding piece moves between a closed position and an expanded position in a radial direction;
external teeth are provided on both the first external tooth arc part and the second external tooth arc part, and a distance from the external tooth on the first external tooth arc part to the central axis decreases sequentially along the direction of the central axis, while a distance from the external tooth on the second external tooth arc part decreases sequentially along the direction of the central axis;
a first radial cross section is taken as an interface between the first external tooth arc part and the first joint arc part, and a second radial cross section is taken as an interface between the first joint arc part and the second external tooth arc part; and a distance from a point on an outer periphery of a largest radial cross section of the first joint arc part to the central axis is not less than a distance from a point on an outer periphery of the first radial cross section to the central axis, and the distance from the point on the outer periphery of the largest radial cross section of the first joint arc part to the central axis is larger than a distance from a point on an outer periphery of the second radial cross section to the central axis; and
a third radial cross section is taken as an interface between the second external tooth arc part and the second joint arc part, and a forth radial cross section is taken as an interface between the second joint arc part and the positioning part; and a distance from a point on an outer periphery of a largest radial cross section of the second joint arc part to the central axis is not less than a distance from a point on an outer periphery of the third radial cross section to the central axis, and the distance from the point on the outer periphery of the largest radial cross section of the second joint arc part to the central axis is larger than a distance from a point on an outer periphery of the forth radial cross section to the central axis.