结构用集成材自动上下料装置真空吸附系统设计与试验

针对结构用集成材加工过程中上下料自动化程度低、劳动强度大、效率低等问题,设计了一种真空海绵吸盘抓取结构用集成材自动上下料装置,实现结构用集成材的高效、自动化上下料作业。选用杉木结构用集成材在自动上下料装置上进行负压与供气压力关系试验和负压与海绵吸盘拉脱力试验。利用MATLAB软件,对试验数据进行最小二乘法函数曲线拟合,建立负压与供气压力的函数关系,最后制定海绵吸盘真空吸附系统控制策略。试验结果表明:海绵吸盘内负压与进气压力密切相关,供气压力为0~630.0 k Pa时为三阶函数关系,当供应压力约为630.0 k Pa时,负压达到最小值-50.3 k Pa,而后随着供气压力的增加,海绵吸盘的真空度基本维持不变且略有减小;海绵吸盘内负压在-50.0~-13.0 k Pa范围内时,负压与拉脱力存在线性关系,但由于有效吸附面积小于理论面积,实测拉脱力比理论值平均小250.0 N;当吸气孔被工件100%,66.7%和33.3%被覆盖时,海绵吸盘内的负压分别为-50.3,-40.0和-35.0 k Pa,拉脱力分别为2 125.0,1 041.9和453.7 N,说明了当海绵吸盘上的吸气孔未被完全覆盖时,海绵吸盘内真空度随未被覆盖的吸气孔增多而减小,未被覆盖的吸气孔越多实测拉脱力减小得越多,海绵真空吸附系统能量损失越大。

Design and test of the automatic loading and unloading vacuum adsorption device for glue-laminated timber

In order to solve the problems of low automation level of loading and unloading,high labor intensity and low efficiency in the processing of glue-laminated timber(GLT),a kind of automatic loading and unloading device for sponge vacuum sucker grab structure was designed to realize the high efficiency and automatic loading and unloading operation of GLT in this paper.So as to verify the rationality,reliability and grasping ability of the sponge sucker vacuum adsorption system,and analyze the factors influencing the grasping force between the workpiece and the sponge vacuum sucker,the relationship between vacuum pressure and air supply pressure,vacuum pressure and pullout force of sponge suction sucker were tested when the GLT,made of Chinese fir,on the automatic loading and unloading device.Using MATLAB,the least square method function curve fitting was used to find out the relationship function and characteristics between the vacuum pressure and air supply pressure.Finally,the control strategy of vacuum sponge adsorption system was formulated.The results showed that:When the supply pressure was about 630.0 kPa,the vacuum pressure reached the minimum value of-50.3 kPa,and then with the increase of air supply pressure,the negative pressure value of sponge suction sucker basically remained stable and increased slightly.There was a good linear relationship between the vacuum pressure and pull-out force when the vacuum pressure was in the range of-50.0 to-13.0 kPa.However,because the effective adsorption area was smaller than the theoretical adsorption area,the measured pull-out force was 250.0 N smaller than the average theoretical value.When the suction hole was covered by 100%,66.7% and 33.3% with the workpiece,the negative pressure in the sponge suction cup was-50.3,-40.0 and 35.0 kPa,accordingly.The results showed that,when the suction holes on the sponge suction sucker were not completely covered,the vacuum degree in the sponge suction cup increased with the increase of the uncovered suction holes.The more the uncovered suction holes were,the more the measured pull-out force decreased,and the greater the energy loss of the sponge vacuum system was found.