摘要
本研究以3種進口材與4種台灣產木材為構件材料，分別就市售寬螺紋、高低雙螺紋、開槽及雙螺紋等4種改良型木螺釘，探討其接合加工時之導引孔徑的適當大小、螺釘埋入深度對引拔抵抗之影響，以及木螺釘共面與非共面組合之側向剪斷抵抗之螺釘保持力，俾供家具製造業者製造、設計或改善結構品質之參考。其主要結果為： 1.本研究直徑級木螺釘類型之最適當導引孔約為1.8 mm（相當於螺紋直徑比40～45%），同時在使用高比重（0.65以上）的木材時，則必須先鑽有較最適導引孔徑略大之導引孔，低比重（0.45以下）的木材，則可不須預先鑽導引孔，甚至採用釘錐尖具有溝槽之開槽木螺釘為佳。 2.改良型木螺釘為獲得良好的引拔抵抗，不論旋入端面或側面木理，應儘可能的選用比重較高的構件木材與提高木螺釘埋入深度；同時對適當木螺釘類型的選擇，除了要瞭解其螺紋幾何性狀、使用適當的導引孔大小之外，尚須考慮其作業之便利性。 3.木螺釘為獲得良好的側向剪斷抵抗，不論共面或非共面組合至少應採用雙釘的接合，且選用較高比重的構件木材，以確保良好的接合性能。
並列摘要
Three imported sawn lumber and four domestic sawn lumber were used as substrate to investigate holding capacity of the four types of modified woodscrews i.e., wide threaded, high-low double-threaded, slotted and double-threaded woodscrews, respectively. The effects of diameter of pilot hole and the embedded depth on withdrawal resistance were examined, and the assembly of flat position and edge position on the lateral resistance were also measured. Fundamental information concerning furniture manufacturing and design, or improvements on the quality of furniture products was studied. The main results indicated as following: 1.Modified woodscrews, like common woodscrews, required pilot hole of the proper size. The optimum pilot hole was approximately 1.8mm, equal to 40-45% of maximum thread diameter. The diameter fit larger than the optimum pilot hole for the dense woods (sp. gr. 0.65 or larger), and pilot hole might not be required or just applying the slotted woodscrews were acceptable for the lightweight wood with sp. gr. 0.45 or less. 2.In order to improve the withdrawal resistance of woodscrews, no matter screwed into the end-grain or side-grain of wood, it was helpful to use dense wood, or to increase the depth of embedment. When choosing proper woodscrew, in addition to understanding the geometrical parameters of thread and the pilot hole of the proper size, the convenience of its operation must be considered also. 3.To obtain good lateral shear resistance of woodscrews no matter the assembled with flat position or edge position, it was helpful to use two-pin screwed joint at least and constructed with dense wood member.