Telescopic tubular extension particularly for electric household appliances and cleaning machines in general

A tubular extension for electric household appliances and cleaning machines, comprising:

• two tubular elements having a longitudinal extension being telscopically connected with each other, a first tubular element of said two tubular elements coaxially telescopically connected with a second tubular element of said two tubular elements, with said second tubular element being slidingly-inserted in said first tubular element;
• a sliding portion being provided at a first one of said first and second tubular element, said sliding portion being shaped so as to form at least one step and to have a transverse cross-section with respect to said longitudinal extension which gradually increases radially along a peripheral arc surface of said sliding portion;
• at least one longitudinal cavity being formed at said peripheral arc surface of said sliding portion;
• at least one protruding tooth being formed at a second one of said first and second element for being said at least one cavity of said sliding portion in a use configuration of said extension in which said first and second tubular elements are stably mutually connected, said at least one tooth being arranged adjacent to said at least one step for acting as a stroke limiter in an adjustable configuration of said extension for allowing said first and second tubular elements to be slideable with respect to each other in a direction of said longitudinal extension, and said at least one tooth sliding over at least part of said peripheral arc surface when said first tubular element is rotated with respect to said second tubular element from said adjustable configuration to said use configuration whereupon said at least one tooth is removably and snugly fit-in said at least one cavity;
• the extension comprising a plurality of steps with plurality of corresponding peripheral arc surfaces which are shaped so as to form gradual increases in cross-section each starting from a corresponding one of said steps, said plurality of peripheral arc surfaces extending about the entire circumference of said sliding-portion.

A tubular extension for electric household appliances and cleaning macheine comprising:

• two tubular elements having a longitudinal extension being telescopically connected with each other, a first tubular element of said two tubular elements being coaxially telescopically connected with a second tubular element of said two tubular elements- with said second tubular element inserted in said first tubular element;
• a sliding portion being provided at a first one of said first and second tubular elements, said sliding portion being shaped so as to form at least one step and to have a transverse cross-section with respect to said longitudinal extension which gradually increases radially aong a peripheral arc surface of said sliding portion;
• at least one longitudinal cavity being formed at said peripheral arc surface of said sliding portion;
• at least one protruding tooth being formed at a second one of said first and second elements for being engaged in said at least one cavity of said sliding portion in a use configuration of said extension in which said first and second tubular elements are stably mutually connected said at least one tooth being arranged adjacent to said at least one step for acting as a stroke limiter in an adjustable configuration of said extension for allowing said first and second tubular elements to be slideable with respect to each other in a direction of said longitudinal extension, and said at least one tooth sliding over at least part of said peripheral arc sur face when said first tubular element is rotated with respect to said second tubular element from said adjustable configuration to said use configuration whereupon said at least one tooth is removably and snugly fit in said at least one cavity;
• said at least one tooth having a chamfered lateral surface directed towards said at least one step, said chamfered surface facilitating disengagement from said at least one cavity when said first tubular element is rotated with respect to said second tubular element out of said use configuration.

A tubular extension comprising:

• a first tubular element;
• a second tubular element which is inserted within said first tubular element such that said second tubular element may freely slide with respect to said first tubular element in a direction corresponding to a longitudinal extension of the tubular extension when the tubular extension is in a length adjustable configuration, and such that said second tubular element may be rotated with respect to said first tubular element out of said length adjustable configuration and into a use configuration of the tubular extension in which said first and second tubular elements are stably mutually connected and blocked from mutually sliding in the longitudinal direction;
• an inner surface of said first tubular surface and an outer surface of said second tubular element, said inner and outer surfaces mutually facing each other;
• an arc-shaped surface portion provided on a first one of said inner and outer surfaces, said arc-shaped surface portion having a gradually increasing radius with respect to a central longitudinal axis of the tubular extension from a minimum radius portion to a maximum radius portion of said arc-shaped surface portion;
• a groove element provided in said arc-shaped surface portion;
• and
• a tooth element provided on a second one of said inner and outer surfaces, said tooth element protruding from said second one of said inner and outer surfaces such that when the tubular extension is in said length adjustable configuration said tooth element is arranged adjacent said minimum radius portion of said arc-shaped surface portion for allowing said second tubular element to be freely slideable with respect to said first tubular element in the longitudinal direction, and such that said tooth is elastically engaged in said groove element when the tubular extension is in said use configuration for stably mutually connecting said first and second tubular elements;
• said groove element extending substantially in said arc-shaped surface portion in a direction which is substantially parallel to said central longitudinal axis of the tubular extension such that said second tubular element may be rotated with respect to said first tubular element out of said length adjustable configuration when said tooth element is arranged adjacent any position of said minimum radius portion of said arc-shaped surface portion for subsequently positioning said tooth element in a selected one of any position in said groove element in said use configuration of the tubular extension.