Research On Brush Sanding Specially Shaped Wood Products

Sanding is an important process in furniture production,now a large number of speciallyshaped wood products with convex or concave surface have appeared,these specially shapedcompents are difficult to sand by machine.Brush sanding is a highly flexible gridingtechnology,A number of recently developed sanding machine are designed with brush sanderrollers.However,brush sanding existed the problem of heavy sanding and unevennesssanding.In order to improve the adaptability and avoid the heavy sanding problem,this paperchoose the radius of the sander roller,rotational speed,feed speed and theoretical contact lengthas variable parameter, researched the change rule of sanding length,choosed the radius ofsander roller, theoretical contact length and angle of sanding strip as variableparameter,researched the change rule of sanding strip’s normal force and choosed the radius ofsander roller, theoretical contact length and rotational speed as variable parameter,researchedthe change rule of sander roller’s normal force. Through the research the following conclusionsare drawn:Set A represents protruding parts and C represents the planar segment. Set r、ω、v、h、L respectively represents the radius of sander roller, rotational speed fee speed, theoreticalcontact length and the sanding length..L increases with the increase of h, but for A, the trend isexacerbated,for C, it albeit more slowly.Both A and C,L in direct proportion to r and ω, andinverse proportion to v. If A is19mm higher than C, L of point A is7.5times higher than pointC.The difference caused for two reasons:the most important reason is that the sanding strip isbent when sanding C,and stright when sanding A. and the next reason is that h of A is higherthan h of C, for A is higher. if the sanding belt is softed, the effect of sanding pattern could bebe weaken, and h become the main reason of the difference of L.The normal pressure of sanding strip decreases with the increase of length,and increaseswith the theoretical contact length and θ.For specially shaped wood products, increase the length of sanding strips could decrease the difference of normal pressure on different plat,andincrease the adaptability.In rotated states, sander roller with different theoretical contact length, appeared thesimilar change ruler. In low rotate speed, normal pressure in a stable condition, and becomerapid increases at a certen rotate speed, and then become increase slowly. The rapid increasesspeed decrease with the length increase of sanding strip.The speed is650r/min、400r/min、300r/min respictively for sanding strips with the length7cm、9cm、11cm. The difference ofnormal pressure for surface with different height could be controled in a low value, and thehigher surface even could be higher than the higher surface.9cm sanding strips arerecommend,when rotated speed is400~550r/min, the sanding result is more uniformity.