Abstract: A hole saw structure, which is cooperated with a hole saw arbor for performing a perforating operation, includes a cylindrical body and a blade set. The cylindrical body has a central chamber and includes an end surface and a peripheral wall. One end portion of the peripheral wall is connected around a circumference of the end surface, the other end portion of the peripheral wall is outwardly folded and overlapped around the peripheral wall so as to form a folded portion, the folded portion includes a folded end, and an inner diameter of the cylindrical body is smaller than an outer diameter of the folded portion. The blade set is disposed on the folded portion and includes at least two cutting teeth and at least two chip discharging notches.

Abstract: A hole saw includes a circular saw blade and a cover plate. The circular saw blade is made by rounding a lengthwise rectangular metal sheet and connecting two ends thereof to define therein an accommodating space. The circular saw blade has one edge provided with a plurality of sawteeth and an opposite edge provided with a connecting portion. The cover plate covers the connecting portion of the circular saw blade and has a base, a positioning portion and a shoulder. The positioning portion extends from the base toward the connecting portion. The shoulder is formed between the base and the positioning portion. Thereby, the hole saw has advantages about low manufacturing costs and short production cycle. Besides, since the shoulder increases contacting area between the circular saw blade and the cover plate, the structural firmness of the soldered hole saw is improved.

Abstract: A hole saw includes a circular saw blade and a cover plate. The circular saw blade is made by rounding a lengthwise rectangular metal sheet and connecting two ends thereof to define therein an accommodating space. The circular saw blade has one edge provided with a plurality of sawteeth and an opposite edge provided with a connecting portion. The cover plate covers the connecting portion of the circular saw blade and has a base, a positioning portion and a shoulder. The positioning portion extends from the base toward the connecting portion. The shoulder is formed between the base and the positioning portion. Thereby, the hole saw has advantages about low manufacturing costs and short production cycle. Besides, since the shoulder increases contacting area between the circular saw blade and the cover plate, the structural firmness of the soldered hole saw is improved.