the disclosed twisting mechanism for a duster is adapted for twisting a dusting cloth c into a spiral shape having a 360 - degree dusting surface in the purpose of eliminating dead spots of the duster . in the preferred embodiment , the dusting cloth c is a stack of layers of non - woven fabrics and heat - fusible intermingled yarn which is integrated as a single unit by means of hot - pressing process , wherein an accommodating recess c 1 is defined at the middle portion of the dusting cloth c by means of hot - pressing process . however , it will be understood that various dusting cloths having other structures or materials may be also applied to the present invention . please refer to fig1 through 7 for a twisting mechanism for a duster according to the present invention , which primarily comprises a brace 10 , a rotating mechanism 20 and a handle 30 . the brace 10 is substantially a column 11 , wherein a plurality of spiral spines 12 are provided at the surface of the column 11 for guiding the twisting direction of the dusting cloth c and a fork portion 111 is formed at the tip of the column 11 for coupling with the end of the accommodating recess c 1 , as shown in fig4 , so that the front end of the dusting cloth c adjacent to the fork portion 111 is set as a fixed end . the rotating mechanism 20 is pivotally connected to the rear end of the brace 10 and a first hook assembly 21 as well as a second hook assembly 22 are provided at the surface thereof , wherein the distance l 1 between the first hook assembly 21 and the tip of the brace 10 is smaller than the distance l 2 between the second hook assembly 22 and the tip of the brace 10 whereby the rear end of the dusting cloth c can be hooked and set as a rotatable end . thus , the rear end of the dusting cloth c , which possesses a relatively smaller length , can be hooked at the first hook assembly 21 , as shown in fig4 . alternatively , the rear end of the dusting cloth c , which possesses a relatively greater length , can be hooked at the second hook assembly 22 ( not shown ). according to the present embodiment , each of the first hook assembly 21 and the second hook assembly 22 is composed of at least two hooks ( 211 , 221 ) wherein each said hook is arranged at one of the opposite sides of the rotating mechanism 20 , respectively . when the rotating mechanism 20 is rotated clockwise or anticlockwise with respect to the brace 10 , the hooks can pull the rotatable end of the dusting cloth c to rotate with respect to the surface of the brace 10 so that the middle portion between the fixed end and the rotatable end of the dusting cloth c can be shaped corresponding to the spiral spines 12 at the surface of the brace 10 into a spiral shape having a 360 - degree dusting surface , as shown in fig5 . thus , the rotational direction of the rotating mechanism 20 has to be set corresponding to the extending direction of the spiral spines 12 . that is to say , when the spiral spines 12 are laid out as an s shape extending from the lower - right to the upper - left , the rotating mechanism 20 shall be correspondingly set as clockwise rotatable . alternatively , when the spiral spines 12 are laid out as a z shape extending from the lower - left to the upper - right , as shown in fig4 , the rotating mechanism 20 shall be correspondingly set as anticlockwise rotatable . the handle 30 is provided at the rear end of the rotating mechanism 20 and has a diameter greater than or equal to that of the rotating mechanism 20 for being held and wielded by a user . further , a coupling structure 31 may be provided at the rear end of the handle 30 for connecting with an extension structure , such as an extension rod 40 , as shown in fig7 . an alternative embodiment of the coupling structure 31 , as shown in fig6 , may comprise a recess 311 passing through the upper and lower surfaces of the rear end of the handle 30 for pivotally receiving the extension rod 40 . each of the left and right walls of the recess 311 has plural positioning protrusions 312 facing those of the other , respectively , and meantime , the front end of the extension rod 40 has plural positioned dents 401 corresponding to the positioning protrusions 312 for controlling the angle between the immovable handle 30 and the extension rod 40 . thereby , the angle θ between the handle 30 and the extension rod 40 can be adjusted steppedly to facilitating reaching an enhanced dusting altitude or distance . the extension rod 40 in the present embodiment is a telescopic extension rod , which is composed of a plurality of telescoped sleeves . please refer back to fig4 through 6 again . to install the dusting cloth c on the twisting mechanism , the brace 10 is firstly inserted into the accommodating recess c 1 of the dusting cloth c , and the fork portion 111 at the tip of the brace 10 is coupled with the accommodating recess c 1 . then the side of the dusting cloth c adjacent to the end of the accommodating recess c 1 is therefore set as a fixed end . subsequently , the opposite end of the dusting cloth c is hooked by either the first hook assembly 21 or the second hook assembly 22 of the rotating mechanism 20 , depending on the length of the dusting cloth c , so that the dusting cloth c can be spread and attached to the brace 10 . at this time , a user can easily rotate the rotating mechanism 20 adjacent to the brace 10 to make the hook assembly drive the rotatable end to rotate . as a result , the middle portion of the dusting cloth c can be twisted along the extending direction of the spiral spines 12 of the brace 10 into a spiral shape having a 360 - degree dusting surface . thereupon , the assembly and configuration of the disclosed subject and the dusting cloth c can be accomplished . as the user is free from touching the surface of the dusting cloth for twisting the dusting cloth directly , his / her hand can be kept clean . besides , the twisting mechanism of the present invention is a unidirectional rotating mechanism 20 and the rotating direction of the rotating mechanism 20 is set corresponding to the extending direction of the spiral spines 12 . therefore , when the brace 10 rotates the rotatable end of the dusting cloth c clockwise or anticlockwise , the dusting cloth can be twisted along the extending direction of the spiral spines 12 into a spiral shape have a 360 - degree dusting surface , which allows a user to dust with improved efficiency . as the dusting cloth c is twisted into the spiral shape , the unidirectional rotating mechanism 20 facilitates retaining the rotatable end of the dusting cloth c at the rotated position and counteracting the tension of the dusting cloth c so as to maintain the spiral shape of the dusting cloth c . although a particular embodiment of the invention has been described in detail for purposes of illustration , it will be understood by one of ordinary skill in the art that numerous variations will be possible to the disclosed embodiments without going outside the scope of the invention as disclosed in the claims .
the present invention relates to a twisting mechanism for a duster for setting one end of a dusting cloth of the duster as a fixed end while setting the opposite end as a rotatable end . the twisting mechanism primarily comprises : a brace , inserted form the rear end through the front end of the dusting cloth and coupled with the front end of the dusting cloth to set it as a fixed end ; and a rotating mechanism , pivotally connected to the rear end of the brace and hooking the rear end of the dusting cloth for driving the dusting cloth to twist into a spiral dusting cloth having a 360 - degree dusting surface on the brace .