Abstract: A rotary cutting unit for a rotary saw has a cross bar and at least one cutting structure, wherein the cutting structure is in contact with the cross bar. The cross bar runs through sleeve holes. The center of gravity of the turning unit is located in an axis of the center of the sleeve holes. The axis is perpendicular to the transverse axis of the crossbar. The rotary saw selectively installs the rotary cutting unit of the corresponding specification, and it can quickly and easily change the aperture of the circular hole to be processed, and with high usability.

Abstract: A rotary cutting unit for a rotary saw has a cross bar and at least one cutting structure, wherein the cutting structure is in contact with the cross bar. The cross bar runs through sleeve holes. The center of gravity of the turning unit is located in an axis of the center of the sleeve holes. The axis is perpendicular to the transverse axis of the crossbar. The rotary saw selectively installs the rotary cutting unit of the corresponding specification, and it can quickly and easily change the aperture of the circular hole to be processed, and with high usability.

Abstract: A rotary cutting unit for a rotary saw has a cross bar and at least one cutting structure, wherein the cutting structure is in contact with the cross bar. The cross bar runs through sleeve holes. The center of gravity of the turning unit is located in an axis of the center of the sleeve holes. The axis is perpendicular to the transverse axis of the crossbar. The rotary saw selectively installs the rotary cutting unit of the corresponding specification, and it can quickly and easily change the aperture of the circular hole to be processed, and with high usability.

Abstract: A center locator is operated with a hole center for enlarging a round opening and includes a center seat having a through hole centrally defined therein, wherein the through hole is adapted to allow a centering drill of the hole cutter extending through the center seat. At least one adjusting device is longitudinally mounted to the center seat and formed with an engaging portion, wherein the at least one adjusting device is expandable relative to the center seat for adjusting a distance between the engaging portion of the at least one adjusting device and a center of the center seat.

Abstract: A polymeric ionic liquid has a formula (I), where A1, A2, B, k, Q, and Z are as defined in the specification. An intermediate polymer for making the polymeric ionic liquid, a process for producing the polymeric ionic liquid, a process for producing a polymer membrane including the polymeric ionic liquid, a process for preparing a gel polymer electrolyte including the polymer membrane, and a binder including the polymeric ionic liquid are also disclosed.

Abstract: A center locator is operated with a hole center for enlarging a round opening and includes a center seat having a through hole centrally defined therein, wherein the through hole is adapted to allow a centering drill of the hole cutter extending through the center seat. At least one adjusting device is longitudinally mounted to the center seat and formed with an engaging portion, wherein the at least one adjusting device is expandable relative to the center seat for adjusting a distance between the engaging portion of the at least one adjusting device and a center of the center seat.

Abstract: A polymeric ionic liquid has a formula (I), where A1, A2, B, k, Q, and Z are as defined in the specification. An intermediate polymer for making the polymeric ionic liquid, a process for producing the polymeric ionic liquid, a process for producing a polymer membrane including the polymeric ionic liquid, a process for preparing a gel polymer electrolyte including the polymer membrane, and a binder including the polymeric ionic liquid are also disclosed.