Research On The Quick Clamping System Of Hydraulic-sleeve For Wood-cutting Tools

To increase rotary speed and feeding speed of cutting tools is a trend in the development of the wood machining equipment. Hydraulic clamping sleeve is now widely adopted in the advanced equipments in wood processing, such as high speed 4-side planer, 2-end miller and so on. Owing to its excellent griping precision of clamping and good performance of dynamic equilibrium and damping, hydraulic clamping sleeve, applied to the wood machines with high speed, can increase the machining precision markedly, improve the quality of the processing surface and prolong the duration of the cutting tools. For all the above-mentioned advantages, the device can be adopted in any wood processing equipment with rotary cutter shaft, such as 2-end millers for processing board furniture, CNC, multi-blade circular saw and 4-side planers.The system developed in the paper has two main functions: one is hydraulic griping, and the other is assembling and unasssembling the tools quickly. To fulfill the first function, two cavities are introduced in the system, and the hydro-medium in the cavities can be pressed to cause the thin walls of the cavities to deform so as to clamp the motor shaft and the tools respectively. The second function is performed by gaseous energy and mechanical energy.Basal theory on the hydraulic clamping sleeve, comprising friction joint theory, principle and method of pressurizing, calculating methods of the thin wall of the sealed cavity, are produced in this paper. The mechanics-calculating model of the sealed cavity in the hydraulic sleeve is also constructed.In the course of the research, CAD technique is introduced in the designing of hydraulic griping part, including the calculating of the pressure and capacity of the hydro-medium, the structure and measure of the cavities, the analysis of the stress and strain of the cavities, and the calculating of fastening torque. CAD technique is also used in the structural devising and optimizing of the quick assembling and unassembling tools.The paper experimented the basal theory on the hydraulic clamping sleeve by measuring the deformation of the thin wall of the cavities and fastening torque transferred via the contact surface of the hydraulic clamping sleeve.Several conclusions can be drawn from the experiments: the basal theory on the hydraulic clamping sleeve is right; the structure of the system is feasible except that the sealing of the pressurizing column is to be improved; 40# industrial oil can be adapted as the hydro-medium in the hydraulic clamping sleeve. The clamping force, transferred by tightening the pressurizing screw above one full circle, can fulfill the driving torque needed by millers.