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Impact mechanism for a hammer drill

January 2006

Authors:

The Hong Kong Polytechnic University

An impact mechanism for a hammer drill, which has a housing and a drill bit protruding outside the housing, is provided. The mechanism includes firstly an impact platform within the housing; the impact platform is in connection with the drill bit for receiving impact forces and for transferring the impact forces to the drill bit. The mechanism also has a plurality of cams within the housing, and the plurality of cams are angularly spaced apart and arranged about an axis of rotation. The mechanism further includes a plurality of hammers placed within the housing and interactable with both the impact platform and the plurality of cams. The plurality of hammers are angularly spaced apart and arranged about the axis of rotation, and each hammer is capable of reciprocating along the axis for exerting the impact forces on the impact platform. Each of the plurality of cam is driven to interact with each of the plurality of hammers alternatively such that the plurality of hammers are driven to reciprocate along the axis so as to generate the impact forces. Inventor name used in publication: Kai-Leung Yung US7137458; US7137458 B2; US7137458B2; US7,137,458; US 7,137,458 B2; 7137458; Appl. No. 10/986,176

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