Archive for January, 2017

The Principle Design of the Cutter Structure of the Drill Hole Chamfering Compound

The aim of the tool design is to provide a tool with high productivity, high precision and low production cost, which combines a drill bit, a reamer and a chamfering knife. The tool comprises a cutter head and a handle. The cutter head is composed of a twist drill bit tapping machine, a reamer and a chamfered part. The reamer tooth is a four-tooth spiral blade, the handle is a straight handle, and the whole cutter structure is an integral type Tool.

(1) Drilling part: According to the high efficiency of drill hole drilling, the drilling part of the tool still adopts the structure of traditional twist drill, and the helix angle of the spiral groove part is 300. Side edge should be grinding out 0.02 – 0.04mm inverted cone to reduce friction mill drill machine, the blade processing of the chip can be smoothly guided to the spiral groove discharge sheet metal fabrication. This part completes the roughing process of the hole, and the roughness and the straightness of the hole are poor, and the dimension precision is not high, so as to prepare for the reaming process.

(2) reaming part: the use of four-tooth double-edged outer-chip reamer, each cutting edge by a precision main cutting edge and a minor cutting edge composition. Work, the main cutting edge from the main cutting effect, auxiliary cutting edge from the role of repair light. The reaming part is placed in the hole to finish the finishing of the hole to ensure the accuracy of the hole (the position accuracy and surface roughness of the hole).

(3) Chamfering: After finishing the hole, continue chamfering the hole with the chamfering knife. Chamfer should be carried out by manual control. As the composite tool is generally used for processing holes with relatively small aperture, so the tool holder part (ie, handle) made of straight handle. In order to facilitate the chip to avoid the cutting tool to participate in various parts of the same time cutting (cutting force reduction), each tool cutting the starting point in the axial direction with a certain interval, but also increases the capacity of chip space, The cuttings from the front and rear flanks interfere and block each other. In addition, the need to consider the tool manufacturing process for the wheel to leave out the appropriate way to slot. Tool size must be determined according to the specific size of the hole.