US Patent 8104138 Portable handheld suction/blower apparatus

A portable handheld suction/blower apparatus includes a motor-driven blower (1) and at least one air guide tube (3) connected to the blower (1) at a connecting location (2) to conduct flow. The connecting location (2) is configured at least as a double-winding connection (9) which has pairs of outer thread sections (4) of an outer winding (5) and inner thread sections (7) of an inner winding (8). The pairs are distributed about the periphery of the threaded connection. The periphery of the connecting location (2) is subdivided by the number of pairs of thread sections (4, 7) into a corresponding number of angular segments (10). The sum of angular extents (α, β) of a pair of individual thread sections (4, 7) is in total less than an angular extent (γ) of the corresponding angular segment (10).