3 Types of Collet Chunk for High Efficient Woodworking Production
The modern woodworking machining technology is developing to high-speed and high efficiency, the main purpose is to improve productivity and reduce costs. For example, when machining a particleboard work piece, the spindle speed from 18,000 r/min increases to 30,000 r/min, that can shorten the working hours by 15%-22%. Furthermore, some using cases show that under certain conditions, the increase of spindle rotating speed can increase the processing quality and extend the tool life. Wooden work piece quality is determined by the cutting tool feed rate (feed tooth) of each cutting tooth and the amount of feed per rotation.
According to the cutting theory, the router bits’ feed rate is smaller, the roughness of work piece will decrease, processing quality will be better. Thus, at an appropriate feed rate to ensure processing quality, the speed can be increased for the high efficacy of cutting tools.
Now, the woodworking spindle motor speed is up to 40,000 r/min. With the increase of the rotating speed of the router bits, the centrifugal force is increase by the square of the rotating speed, which will cause a problem of safety and reliability, and thus requires the tool and the clamping device of a higher precision.
High efficiency of wood cutting tool clamp device
Tool clamping mechanism connecting a router bit to the spindle, which function is: greater rigidity to hold the tool securely, transmitting torque to the cutting tools, to ensure small runout and a good balance at the same time. In order to meet the requirements of high-efficiency wood cutting, there are two types of tool tightening devices with good performance.
1, Hydraulic tool holder (the tool collet chuck made by the elastic steel, by so-called shrinkage force to tighten the cutting tool).
(a) In the normal state, the cross section of the inner cavity of the collet is similar to a triangle (unrecognizable by the human eye), the diameter of the inscribed circle is slightly smaller than the diameter of the tool shank, and the tool cannot be inserted at this time.
(b) Using hydraulic device for applying a certain force to the inner cavity. Due to the elastic deformation, the cross section of the triangle becomes circular.
(c) When the hydraulic pressure in the chuck is eliminated, the cross section of the chuck inner cavity returns to a triangle and shrinks, so a high-precision and firm three-point tightening device is formed.
The main characteristics of this chuck are: high clamping accuracy, the eccentricity is only 0.003mm, the clamping force is large, and the torque that can be transmitted exceeds 200N•m when the clamping diameter is 25mm.
2, Heat-shrink tool collet chuck
Heat-shrink means that the tool chuck will expand by heating, and then shrunk by cooling. When the chuck is loosened, the chuck is heated to 200-300 ° C by an electromagnetic inductor, and the chuck is expanded to remove the router bit; the replaced tool shank is inserted into the chuck and cooled in the cooling adapter, and the chuck shrink to clamp the tool. The heating time is only a few seconds, and the work preparation time is less than 1 minute.
Due to its compact whole structure and rotationally symmetric structure, as well as shrink-clamping tool holders during cooling, they have large rigidity, high tightening accuracy, large clamping force, and good balance. These indicators are similar to force-shrinking chucks.
3, Ordinary type of collet chuck
Ordinary type collet chuck use the nut to shrink the collet, collet hold the cutter tits tightly. As a result of abrasion in wear and expansion, the level of imbalance increases. The clamping accuracy of the force-shrink and heat-shrink chucks is always the same. The overall imbalance formed is about 80% lower than used ordinary collet, and is lower than the new one 70%; to the normal hydraulic collet chuck, the imbalance is about 30% lower.
Compared with ordinary tool chucks, force-shrink and heat-shrink collet chucks allow high speed and smooth rotation, low vibration, low noise, good durability, and good cutting quality. All these advantages make them especially suitable for high-efficiency wood cutting.
And the tool clamp device use life can be increased by 20% -50%, in some cases can be increased 2-3 times, but their price are very high at this moment.
The ordinary type collet chuck for woodworking now also can be balanced to 36000rpm, and total precision with 0.01mm. (toolholder body precision 0.003mm, collet precision 0.005mm, cutting mills precision 0.002mm)
As most spindle for woodworking maximum rotating speed is 18000rpm or 24000rpm. The ordinary tool holders also suitable for normal woodworking production with a lower cost and good function.
RicoCNC supplies a range of high quality CNC tool holder chucks for woodworking, such as ISO30, HSK63F and BT30 tool holders. If any needs, welcome your inquiry.
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