US 12,280,473 B2
Power tool and main shaft thereof
Jeff Liu, Taichung (TW)
Filed by Jeff Liu, Taichung (TW)
Filed on Jan. 5, 2021, as Appl. No. 17/141,529.
Application 17/141,529 is a continuation in part of application No. 16/008,292, filed on Jun. 14, 2018, abandoned.
Claims priority of application No. 107108130 (TW), filed on Mar. 9, 2018.
Prior Publication US 2021/0122014 A1, Apr. 29, 2021
Int. Cl. B25B 21/02 (2006.01); B25D 17/26 (2006.01)
CPC B25B 21/02 (2013.01) [B25D 17/265 (2013.01); B25D 2217/0096 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A power tool assembly comprising:
an impact device having a rotary set with a passage laterally defined therein and a through hole longitudinally defined therein, the through hole communicating with the passage;
at least one impact block mounted in the passage;
a main shaft sequentially divided into an impact section and a penetrative section and an output section, the impact section having at least one portion and having at least one curved recess defined therein, the at least one portion corresponding in location to the at least one impact block, the output section and the penetrative section adapted to extend sequentially through a front end of the power tool assembly so as to output power therefrom, said main shaft having a linear tunnel defined therein, the linear tunnel having opposite ends respectively defined as an inlet and an outlet, the inlet of the linear tunnel being positioned in the output section of said main shaft, the outlet of the linear tunnel being positioned in the impact section of said main shaft in a location corresponding to the at least one impact block, wherein an axis L1 of the linear tunnel and an axis L2 of said main shaft intersect so as to form an included angle, the included angle being between 20° and 70°, the outlet of the linear tunnel being positioned in the curved recess, the inlet and the outlet of the linear tunnel being located respectively at opposite ends of said main shaft such that said main shaft defines a first side and an opposite second side of axis L2, wherein the inlet extends through the first side of said main shaft and extends through the opposite second side of said main shaft, wherein a lubricant space is formed between the curved recess and said at least one impact block at an end of the impact section that passes through said main shaft.