Telescopic coupling tube for a vacuum cleaner

Abstract

A telescopic coupling tube for a vacuum cleaner includes a mounting tube, a connecting sleeve, a sealing sleeve, a telescopic tube, a locking assembly, and a positioning cap. The connecting sleeve is provided for the insertion of the telescopic tube. A guide slot and toothed engaging holes are formed in the telescopic tube. Based upon the interaction of the above-mentioned components, an easy adjustment of the assembly length is achieved.

1 . A telescopic coupling tube for a vacuum cleaner, comprising:
 a) a mounting tube having a mounting portion at one end thereof for attaching to an inserting part of accessories of a vacuum cleaner and an insertion portion at the other end thereof, a slot being formed in the second insertion portion;   b) a connecting sleeve mounted on the insertion portion of the mounting tube, the connecting sleeve having opening corresponding to the slot of the insertion portion;   c) a sealing sleeve fitting into an internal hole of the mounting tube, the sealing sleeve is provided with a locking portion facing to the slot of the mounting tube, the locking portion having a locking slot at both sides thereof, two projections being positioned near the center of the sealing sleeve, a notch being disposed at the side portion of the projections;   d) a telescopic tube having one end into which a positioning cap is plugged, a mounting portion being positioned at the other end thereof for attaching to an inserting part of accessories of a vacuum cleaner, a guide slot being axially formed at the end surface of a locking assembly, one side of the guide slot being provided with toothed engaging holes;   e) a locking assembly having a push knob, an engaging element, and an elastic element, an engaging hook being positioned at both sides of the internal surface of the push knob, a push lug being disposed at a certain position of the locking assembly, the engaging element being substantially curved and having positioning holes at both sides thereof, a push piece being positioned near the center of the engaging element, a push surface being disposed at one side of the push piece while an engaging cambered surface is positioned at the other side thereof, the engaging cambered surface of the push piece being extended downward to pass through the notch of the sealing sleeve and then to engage into the engaging hole of the guide slot of the telescopic tube, the elastic element being supported against a portion between the push lug of the push knob and the locking portion of the sealing sleeve; and   f) a positioning cap plugged into and positioned within an internal hole at one side of the telescopic tube,   
     whereby the elastic element normally applies a force acting backward such that the push knob is constantly compressed in a pushed position; at that time, the push lug is just pushed against the push surface of the push piece of the engaging element while the engaging cambered surface at the other end of the push piece is engaged into one of the toothed engaging hole of the guide slot of the telescopic tube, thereby creating an engaging effect, 
     wherein, when the push knob is pushed, the push lug is free from the contact with the push piece of the engaging element such that the engaging element is returned to the original bent position; as a result, the engaging cambered surface of the push piece is released from the toothed engaging hole of the guide slot of the telescopic tube.