Patent Publication Number: US-2017350188-A1

Title: Cordless shade roller

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a cordless shade roller, especially to a cordless shade roller in which a cord for retraction or extension of the shade is replaced by an S-shaped constant force spring. 
     Cordless shades are common shades designed for prevention of strangulation hazard to children from conventional shade cords. Refer to U.S. Pat. No. 5,787,952, U.S. Pat. No. 324,135, U.S. Pat. No. 2,868,285, U.S. Pat. No. 6,474,394, and U.S. Pat. No. 8,251,120, these are all related to cordless shades. Most of them use an S-shaped constant-force spring (or spring-steel ribbon in U.S. Pat. No. 8,251,120) to replace the cord for retracting or extending a roller tube of the shades. The S-shaped constant-force spring generally includes an S-shaped spring wound around a first wheel (or storage drum in U.S. Pat. No. 6,474,394) and a second wheel (or output drum in U.S. Pat. No. 6,474,394) respectively. The structure of the S-shaped constant-force spring is already known. Although the respective shade of these prior arts includes the S-shaped constant-force spring, they have different designs and structure. Or the use/type of the shade is limited. Thus these prior arts have been granted. 
     Refer to U.S. Pat. No. 8,251,120, a cordless blind structure is revealed. The cordless blind structure includes a blind body (1), a first end holder (2), a second end holder (3) and a limiting mechanism (4). The components, the structure and connection between the components are all defined in the claim  1 . Thus the use/kind of the blind is limited. At the pleading stage of the case, the applicant further integrated the original claim  5  (dependent claim) “wherein the resilient unit further comprises a constant-force spring and baffles flanking the constant-force spring, the constant-force spring having an end disposed at the second end holder and another end coupled to the axial unit” into the claim  1  (independent claim). The claim scope was narrowed so that this patent has been granted. Thus it is learned that not only the use of the blind (the type of the blind, refer to claim  1 ) is limited, the structure/type of the resilient unit (41) of the limiting mechanism (4) is further limited due to the new limitation (original claim  5 ) within the claim of U.S. Pat. No. 8,251,120. For example, the resilient unit 41 comprises a constant-force spring 411 and baffles 412 flanking the constant-force spring 411. The baffles 412 flanking the constant-force spring 411 have become one of the elements of the claim. 
     The prior arts mentioned above have the following shortcomings: Firstly, although the above shades use an S-shaped constant force spring, the structure of the S-shaped constant force spring has been modified to have different designs. For example, the resilient unit (41) in U.S. Pat. No. 8,251,120 includes the baffles 412 flanking the constant-force spring 411 so that the applications of the resilient unit (41) have limitations. For production of a type of blind, an S-shaped constant force spring matched with the blind should be designed and molded. Each blind requires a specially-designed S-shaped constant force spring. The S-shaped constant force spring is not a standardized component. Thereby the manufacturing cost is increased. This has negative effect on mass production and production management of the S-shaped constant force spring. 
     Secondly, the respective S-shaped constant force spring of each blind has a plurality of components and complicated structure. For example, the resilient unit 41 in U.S. Pat. No. 8,251,120 includes the baffles 412 flanking the constant-force spring 411. The assembly of the resilient unit 41 is getting difficult and more space required for installation of the resilient unit 41. The use efficiency of the resilient unit 41 is reduced. 
     The conventional design of the S-shaped constant force spring has complicated structure, the problem of unable to be standardized, higher manufacturing and assembly cost and lower use efficiency, Thus there is room for improvement and a need to provide a novel design of the S-shaped constant force spring. 
     SUMMARY OF THE INVENTION 
     Therefore it is a primary object of the present invention to provide a cordless shade roller that includes an S-shaped constant force spring that features on simple structure, standardization, lower manufacturing and assembly cost, and minimum space required. 
     In order to achieve the above object, a cordless shade roller according to the present invention includes a roller tube, a passive-end bracket arranged at a first end of the roller tube, and an active-end bracket set on a second end of the roller tube. The active-end bracket consists of a first cover, a second cover, and an S-shaped constant force spring. The S-shaped constant force spring includes a first wound roll used as a storage drum, a second wound roll used as an output drum, and an S-shaped spring strip wound around the first wound roll and the second wound roll. The first cover and the second cover are assembled to form a cover body with a narrow space therein. The S-shaped constant force spring is clipped in the narrow space. No baffle is disposed on each of two sides of the first wound roll and the second wound roll of the S-shaped constant force spring. 
     The cordless shade roller can be used in a blade-spring-type zebra shade, a blade-spring-type roller shade, or a blade-spring-type Shangri-la blind. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing an embodiment of a cordless shade roller applied to a blade-spring-type zebra shade according to the present invention; 
         FIG. 2  is a side view of the embodiment shown in  FIG. 1  according to the present invention; 
         FIG. 3  is an explosive view of the embodiment shown in  FIG. 1  according to the present invention; 
         FIG. 3A  is an enlarged view of an S-shaped constant force spring of the embodiment in  FIG. 3  according to the present invention; 
         FIG. 4  is an explosive view of the embodiment shown in  FIG. 3  viewed from another angle according to the present invention; 
         FIG. 4A  is an enlarged view of an S-shaped constant force spring of the embodiment in  FIG. 4  according to the present invention; 
         FIG. 5  is an enlarged view of an active-end bracket of the embodiment in  FIG. 4  according to the present invention; 
         FIG. 6  is a perspective view showing an embodiment of a cordless shade roller applied to a blade-spring-type roller shade according to the present invention; 
         FIG. 7  is a side view of the embodiment shown in  FIG. 6  according to the present invention; 
         FIG. 8  is an explosive view of the embodiment shown in  FIG. 6  according to the present invention; 
         FIG. 9  is an explosive view of the embodiment shown in  FIG. 8  viewed from another angle according to the present invention; 
         FIG. 10  is an enlarged view of an active-end bracket of the embodiment in  FIG. 9  according to the present invention; 
         FIG. 11  is a perspective view showing an embodiment of a cordless shade roller applied to a blade-spring-type Shangri-la blind according to the present invention; 
         FIG. 12  is a side view of the embodiment shown in  FIG. 11  according to the present invention; 
         FIG. 13  is an explosive view of the embodiment shown in  FIG. 11  according to the present invention; 
         FIG. 14  is an explosive view of the embodiment shown in  FIG. 11  viewed from another angle according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Refer from  FIG. 1  to  FIG. 5 , a cordless shade roller  1  of the present invention is used in a blade-spring-type zebra shade  2 . 
     The zebra shade includes a zebra fabric having transparent sections and non-transparent sections placed in parallel positions alternatively. The zebra fabric is used in combination with other accessories to form a front fabric and a rear fabric moved relative to each other. The overlapping of the transparent/non-transparent sections of the front/rear fabric can be adjusted by an operating mechanism. When the transparent sections of the front/rear fabric and the transparent sections of the rear/front fabric are completely overlapped and corresponding to each other, the shade is in a transparent state. Once the transparent sections of the front/rear fabric and the non-transparent sections of the rear/front fabric are completely overlapped and corresponding to each other, the shade is in a totally shaded (non-transparent) state. While the transparent/non-transparent sections of the front/rear fabric are partially overlapped, the shade is in a partially transparent/shaded state. Thus the adjustment of the Zebra shade transparency has been achieved. 
     Refer to  FIG. 1  and  FIG. 2 , a blade-spring-type zebra shade  2  is installed on an indoor side of a window  201 . The installation way is not limited. For example, the zebra shade is affixed to an upper edge of the window  201  (ceiling) or walls on two sides thereof by brackets  202 . The blade-spring-type zebra shade  2  mainly includes a zebra fabric  203  with a certain length/height, a head end  204  of the zebra fabric  203 , a lower rod  205 , a tail end  206  of the zebra fabric  203 , a front fabric  207  and a rear fabric  208 . The head end  204  of the zebra fabric  203  is wound and retracted around an outer surface  11  of a roller tube  10  while the zebra fabric  203  is extended from the head end  204  downward, wound around the lower rod  205  and then turned to extend upward. The tail end  206  of the zebra fabric  203  is fixed on and suspended from an upper edge. Thereby the zebra fabric  203  is divided into the front fabric  207  and the rear fabric  208  by the lower rod  205 . The front fabric  207  and the rear fabric  208  are moved relative to each other. 
     Refer to  FIG. 3  and  FIG. 4 , a roller of cordless shades  1  according to the present invention is composed of a roller tube  10 , a first shaft part  20 , a second shaft part  30 , a passive-end bracket  40 , and an active-end bracket  50 . 
     An outer surface  11  of the roller tube  10  is wound with the zebra fabric  203  of the blade-spring-type zebra shade  2 . The first shaft part  20  is disposed on a first end  12  in an axial direction of the roller tube  10  and the second shaft part  30  is arranged at a second end  13  of the roller tube  10  that is opposite to the first end  12  of the roller tube  10 . 
     The first shaft part  20  includes an axis part  21  extended outward and an outer shaft part  22  that is mounted in the first end  12  of the roller tube  10 . Thus the roller tube  10  and the outer shaft part  22  can be rotated relative to the axis part  21 . 
     The second shaft part  30  includes an axis part  31  extended outward and an outer shaft part  22  that is mounted in the second end  13  of the roller tube  10 . Thus the roller tube  10  and the second shaft part  30  can be rotated synchronously. 
     The passive-end bracket  40  is set outside the first shaft part  20  on the first end  12  of the roller tube  10  and is having an axis base  41  used for supporting the axis part  21  of the first shaft part  20 . 
     The active-end bracket  50  consists of a first cover  51 , a second cover  52  and an S-shaped constant force spring  53  clipped in a narrow space formed by assembly of the first cover  51  with the second cover  52 . Two separate pins  511  are extended from an inner side of the first cover  51  toward the second cover  52 . The second cover  52  is set with two separate holes  521  corresponding to the separate pins  511  respectively. The S-shaped constant force spring  53  includes a first wound roll  531 , a second wound roll  532 , and an S-shaped spring strip  533 . The first wound roll  531  is fitted on one of the pins  511  and is used as a storage drum. The second wound roll  532  is fitted on the other pin  511  and is used as an output drum. The S-shaped spring strip  533  is wound around the first wound roll  531  and the second wound roll  532  in a reversible way, as shown in  FIG. 3A . The first cover  51  and the second cover  52  are assembled to form a cover body with a narrow space therein. 
     Refer to  FIG. 5 , the first wound roll  531  and the second wound roll  532  of the S-shaped constant force spring  53  are fitted on the pins  511  correspondingly while being assembled. The S-shaped spring strip  533  is wound around the first wound roll  531  and the second wound roll  532  reversibly, as shown in  FIG. 3A . Then the second cover  52  is covered on. The axis part  31  extended outward from the second shaft part  30  is passed through the corresponding hole  521  to be mounted in an axial hole  534  of the second wound roll  532 . Thus the second wound roll  532  and the second shaft part  30  can be rotated synchronously along with the roller tube  10  under the action of the S-shaped constant force spring  53 . 
     The present invention features on that the S-shaped constant force spring  53  is directly clipped in the narrow space formed by the first cover  51  assembled with the second cover  52 . No baffle is disposed on each of two sides of the first wound roll  531  (storage drum) and of the second wound roll  532  (output drum), as shown in  FIG. 3A ,  FIG. 4A  and  FIG. 5 . The manufacturing and assembly cost of the baffle is saved. There is no need to reserve the space required for arrangement of the baffle. 
     Refer from  FIG. 6  to  FIG. 10 , a cordless shade roller  1  of the present invention is used in a blade-spring-type roller shade  3 . The structure of the cordless shade roller  1  used in the blade-spring-type roller shade  3  is the same as the structure of the cordless shade roller  1  shown from  FIG. 1  to  FIG. 5 . 
     The blade-spring-type roller shade  3  is a common blind. The blade-spring-type roller shade  3  of this embodiment is disposed on an indoor side of a window  301 . The installation way is not limited. For example, the shade  3  is fastened on an upper edge of the window  301  (such as ceiling) or walls on two sides thereof by brackets  302 . The blade-spring-type roller shade  3  is composed of a fabric  303  with a certain length/height. A head end of the fabric  303  is wound and retracted around an outer surface of a roller tube  10  of the roller  1  while a rear end (lower end) of the fabric  303  is covered over a lower rod (or a weighted rod)  304 . The fabric  303  is extended downward by the lower rod (or a weighted rod)  304  being pulled down, or retracted upward and wound around the roller tube  10  by the lower rod (or a weighted rod)  304  being activated, as break lines shown in  FIG. 7 . 
     Refer from  FIG. 11  to  FIG. 14 , a cordless shade roller  1  of the present invention is used in a blade-spring-type Shangri-la blind  4 . The structure of the cordless shade roller  1  used in the blade-spring-type Shangri-la blind  4  is the same as the structure of the cordless shade roller  1  shown from  FIG. 1  to  FIG. 5 . 
     The blade-spring-type Shangri-la blind  4  is a common blind. The blade-spring-type Shangri-la blind  4  of this embodiment is arranged at an indoor side of a window  401 . The installation way is not limited. For example, the blind  4  is secured on an upper edge of the window  401  (such as ceiling) or walls on two sides thereof by brackets  402 . The blade-spring-type Shangri-la blind  4  consists of a transparent front fabric  403  fixed on one side of a roller tube  10 , a transparent rear fabric  404  attached to the other side of the roller tube  10 , and a plurality of non-transparent step-like fabric  405  vertically arranged at equal intervals in an S-shaped manner between the front fabric  403  and the rear fabric  404 . A lower rod (or weighted rod)  406 ,  407  is set on a bottom end of the front fabric  403  and the rear fabric  404  respectively. While in use, the transparent front fabric  403  and the rear fabric  404  are separated from each other and located at a front side and a rear side respectively while each non-transparent step-like fabric  405  is vertically arranged between the front fabric  403  and the rear fabric  404  in an S-shaped manner, as shown in  FIG. 11  and  FIG. 12 . The lower rod (or the weighted rod)  406  of the front fabric  403  is pulled to the lowest position and then the lower rod  407  of the rear fabric  404  is pulled. Thus the blade-spring-type Shangri-la blind  4  is in an opened state and the user can see through the blind. At the moment, the lower rod  406  of the front fabric  403  is pulled down a bit and then is pushed upward so that the transparent front fabric  403  and the rear fabric  404  are closed to each other and each non-transparent step-like fabric  405  is in a vertical state. Thus the blade-spring-type Shangri-la blind  4  is in a closed state and the user can&#39;t see through the blind. For retracting the blade-spring-type Shangri-la blind  4 , the lower rod (or weighted rod)  406  of the front fabric  403  is pushed to activate the roller  1 . Thereby the front fabric  403  and the rear fabric  404  are retracted and wound around the roller tube  10  by the action force of the S-shaped constant force spring  53 , as break lines shown in  FIG. 12 . The blade-spring-type Shangri-la blind  4  is in the retracted form. 
     Although the embodiment of the cordless shade roller  1  being applied such as the blade-spring-type roller shade  3 /or the blade-spring-type Shangri-la blind  4  is different from the blade-spring-type zebra shade  2  shown in  FIG. 1  to  FIG. 5 , the function and purpose of the cordless shade roller  1  according to the present invention are almost the same. The only difference is in the shape/design of the passive-end bracket  40 , the shape/design of the first cover  51  and the second cover  52  of the active-end bracket  50 , or the arrangement of the two pins  511  of the first cover  51 . The arrangement of the pins  511  is determined according to the installation direction, either in the vertical or horizontal direction. The installation direction of the pins  511  also affects the position of the S-shaped constant force spring  53  or the relative position of the first wound roll  531  and the second wound roll  532 . For example, the shape of the active-end bracket  50  shown in  FIG. 3-5  is different from that of the active-end bracket  50  shown in  FIG. 8-10 . 
     During production, the shape, the design of the appearance or the position of a part of the components of the cordless shade roller  1  such as the passive-end bracket  40 , the first cover  51  and the second cover  52  of the active-end bracket  50 , the two pins  511  of the first cover  51 , etc. can be modified or not in various applications such as the blade-spring-type zebra shade  2 , the blade-spring-type roller shade  3 , or the blade-spring-type Shangri-la blind  4  as long as the function and purpose of the cordless shade roller  1  remain the same. Thus the cordless shade roller  1  with the same specification, shape or the design of the appearance can be applied to the blade-spring-type zebra shade  2  shown in  FIG. 1-5 , the blade-spring-type roller shade  3  shown in  FIG. 6-10 , or the blade-spring-type Shangri-la blind  4  shown in  FIG. 11-14 . 
     Moreover, the area around the two separate pins on the inner side of the first cover  51  and the area around the inner side of the two separate holes  521  of the second cover  52  are integrated with at least one projecting guide member  512 ,  522  respectively. The projecting guide members  512 ,  522  are used to replace the baffles set on two sides of the second wound roll  532  and/or the first wound roll  531  and limit the movement of the S-shaped spring strip  533  wound around the first wound roll  531  and the second wound roll  532  reversibly. The projecting guide members  512 ,  522  can also guide the S-shaped spring strip  533  to be wound around the first wound roll  531  and the second wound roll  532  orderly. 
     As to the shape of the projecting guide members  512 ,  522 , it is not limited. Take the projecting guide members  512 ,  522  of the embodiments shown in  FIG. 5  and  FIG. 10  as examples. The projecting guide members  512 ,  522  are designed into long ribs with a certain length. 
     Furthermore, in the embodiments shown in  FIG. 5  and  FIG. 10 , two long ribs are disposed on the area around the pins  511  and used as the projecting guide members  512 . Similarly, two long ribs are arranged at the area around the holes  521  and used as the projecting guide members  522 . The two long ribs ( 512 ) in  FIG. 5  and  FIG. 10  are (but not limited to) parallel to each other and so are the tow long ribs ( 522 ). The two long ribs ( 512 ,  522 ) can also be not parallel to each other. 
     Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, and representative devices shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.