Patent Publication Number: US-11028642-B2

Title: Roller shade actuation device

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to window shade technical field and, more particularly to a roller shade actuation device. 
     2. Description of Related Art 
     Roller shades are a type of curtain products that roll shade bodies on winding drums to form rollers and use cords or chains to do up-and-down controls, which are easy to operate, and among which, there is a roller shade which is called a spring roller shade due to a built-in spring device of a winding drum, also known as a semi-automatic roller shade. 
     Opposite ends of a winding drum of a current spring roller shade are mounted to corresponding brackets, and a spring end, a coil spring, a damper, and a limiter are arranged in order from an end to an opposite end in the winding drum. When the shade body needs to be put down, the shade body only needs to be pulled down, and the shade body will drive the winding drum to rotate and then rotate relative to the coil spring. The coil spring is twisted and deformed to accumulate elastic force. At the same time, by means of the damper, the shade body can be held at any height position within the effective range of the shade body. When the shade body needs to be rolled up, the shade body only needs to be pushed up, and the force of the coil spring overcomes the damping action of the damper to drive the winding drum to rotate in an opposite direction, thereby rewinding the shade body on the winding drum. The current spring roller shade uses the coil spring, and the whole coil spring is deformed during the action, which makes the generated elastic force difficult to be controlled effectively. When the elastic force is too large, it is easy to make the shade body rise rapidly, causing a lower supporting pole to hit an upper beam, and the damper has to be added to slowly release the elastic force of the coil spring, which will leads to relatively complicated structures, and high costs of components and assembly. 
     SUMMARY OF THE INVENTION 
     Therefore, the technical problem to be solved by the embodiments of the present invention is to provide a roller shade actuation device, which is capable of smoothly actuating the roller shade to be retracted or released. 
     To solve the above-mentioned technical problems, an embodiment of the present invention provides a roller shade actuation device for actuating a winding drum with an outer surface mounted with an end of a shade body and opposite ends rotatably mounted to corresponding frames with the help of pivots, and the actuation device is mounted between one of the frames and the winding drum, the roller shade actuation device includes a middle shaft rotatably mounted to an inner sidewall of the frame, a plane scroll spring mounted outside the middle shaft and axially parallel to the middle shaft, and a pivot relatively fixed in a circumferential direction with the end of the winding drum, and connected to the middle shaft through shaft connection, an outer end of a reed of the plane scroll spring is fixed to an outer surface of the middle shaft. 
     Furthermore, the inner sidewall of the frame forms at least one pole, each of the at least one pole is fitted about one said plane scroll spring, the outer ends of the reeds of the plane scroll springs are fixed to different positions of the outer surface of the middle shaft. 
     Furthermore, the pole is fitted about a bushing, and the plane scroll spring is fitted about the bushing. 
     Furthermore, the pivot includes an insertion end for being inserted into an inner cavity of the corresponding end of the winding drum, and a connection shaft located at an end of the insertion end away from the winding drum; the insertion end is mutually engaged with an inner wall of the inner cavity of the winding drum to allow the insertion end and the winding drum to be relatively fixed in the circumferential direction; the insertion end forms a limit piece for being abutted against an outer end surface of the winding drum, the connection shaft is connected to the middle shaft through shaft connection. 
     Furthermore, an end wall of an end of the middle shaft facing the winding drum defines a connection hole, the connection shaft is inserted into the connection hole, cross sections of the connection hole and the connection shaft are matched and are non-circular to allow the winding drum and the connection shaft to be relatively fixed in the circumferential direction, or a fixing pin extends into the connection hole through a sidewall of the middle shaft to be inserted into the connection shaft, so as to fixedly connect the connection shaft and the middle shaft. 
     Furthermore, the frame defines a round hole, an end of the middle shaft is cylindrical and inserted into the round hole; an end wall of the end of the middle shaft inserted into the round hole defines a non-circular operation hole. 
     Furthermore, the insertion end is a hollow tube and only opens at an end adjacent to the connection shaft, the connection shaft is inserted into the tube, cross sections of the connection shaft and an inner tube hole of the tube are matched and are non-circular. 
     Furthermore, a wall of the tube defines a slot extending through the wall of the tube and extending along an axial direction of the tube; the connection shaft forms a hook engaged in the slot, a compressed spring is arranged in the tube and resiliently abutted against the end of the connection shaft inserted into the tube. 
     Furthermore, an inner wall of the winding drum protrudes toward a center of the inner cavity of the winding drum to form a protrusion, an outer wall of the insertion end correspondingly defines an insertion slot, when the insertion end is inserted into the inner cavity of the winding drum, the protrusion is correspondingly engaged in the insertion slot. 
     Furthermore, the roller shade actuation device further includes a cover mounted to the inner sidewall of the frame rotatably mounted with the middle shaft, the cover and the frame cooperate to form a closed mounting cavity, the middle shaft and the plane scroll spring are mounted in the mounting cavity, and the cover defines a through hole for exposing the middle shaft. 
     By adopting the above-mentioned technical solutions, the beneficial effects of the embodiments of the present invention are as follows. By providing the roller shade actuation device between one of the frames and the winding drum, and using the planar scroll spring to provide an actuation force, the actuation force required for the winding of the shade body can be better designed. Moreover, the overall structure is simple, easy to assemble and easy to handle. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a partially exploded, isometric view of an embodiment of a shade actuation device of the present invention. 
         FIG. 2  is a partially exploded, isometric view of the embodiment of the shade actuation device of the present invention, but viewed from another perspective. 
         FIG. 3  is a cross-sectional view of the embodiment of the roller shade actuation device. 
         FIG. 4  is a schematic view of the embodiment of the roller shade actuation device. 
         FIG. 5  is a schematic view of another embodiment of the roller shade actuation device. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the following illustrative embodiments and illustrations are only used to explain the present invention and are not intended to limit the invention, and that the embodiments of the present invention and the features of the embodiments can be combined with each other without conflict. 
     Referring to  FIGS. 1-4 , an embodiment of the present disclosure provides a roller shade actuation device for actuating a winding drum  1  with an outer surface mounted with an end of a shade body  100 . Opposite ends of the winding drum  1  are rotatably mounted to corresponding frames  3 . The roller shade actuation device is mounted between one of the frames  3  and the winding drum  1 , and includes a middle shaft  40  rotatably mounted to an inner sidewall of the frame  3 , a plane scroll spring  42  mounted outside the middle shaft  40  and axially parallel to the middle shaft  40 , and a pivot  44  relatively fixed in a circumferential direction with the end of the winding drum  1 . The middle shaft  40  is connected to the pivot  44  through shaft connection. An outer end of a reed of the plane scroll spring  42  is fixed to an outer surface of the middle shaft  40 . 
     In the embodiment, by providing the actuation device between one of the frames  3  and the winding drum  1 , and using the plane scroll spring  42  to provide an actuation force, the actuation force required for the shade body to be retracted or released can be better designed. The overall structure is simple, and is easy to be assembled and manipulated. 
     In an embodiment of the present invention, the inner sidewall of the frame  3  is mounted with at least one pole  30 . Each pole  30  is fitted about one said plane scroll spring  42 . The outer ends of the reeds of the plane scroll springs  42  are fixed to different positions of the outer surface of the middle shaft  40 . For example, in the embodiment shown in  FIG. 4 , one plane scroll spring  42  is assembled, while in the embodiment shown in  FIG. 5 , two plane scroll springs  42  are assembled. In the embodiment, the middle shaft  40  can be actuated together by providing a plurality of plane scroll springs  42 , which can more flexibly design the corresponding actuation force distribution of the shade body at different height positions according to the width and the weight of the shade body, and can also facilitate the design and manufacture of the planar scroll springs  42  and reduce costs. In an embodiment shown in  FIG. 4 , the pole  30  is fitted about a bushing  32 . The plane scroll spring  42  is fitted about the bushing  32 . By adding the bushing  32 , it is possible to adapt to the plane scroll springs  32  of different inner diameters, in particular to avoid noise problems caused by the excessive clearance between the inner diameter of the plane scroll spring  42  and the pole  30 . 
     Referring to  FIGS. 1 and 3 , the roller shade actuation device further includes a cover  34  mounted to the inner sidewall of the frame  3  rotatably mounted with the middle shaft  40 . The cover  34  and the frame  3  cooperate to form a closed mounting cavity. The middle shaft  40  and the plane scroll spring  42  are mounted in the mounting cavity, and the cover  34  defines a through hole  340  for exposing the middle shaft  40 . By providing the cover  34 , the middle shaft  40  and the plane scroll spring  42  can be covered. The movable parts are not exposed, it can avoid the bad phenomenon, such as jamming of foreign objects falling in, and it can also make the overall structure more concise. 
     In another embodiment of the present invention, the pivot  44  includes an insertion end  440  for being inserted into an inner cavity  10  of a corresponding end of the winding drum  1 , and a connection shaft  442  located at an end of the insertion end  440  away from the winding drum  1 . The insertion end  440  is inserted into the winding drum  1  and is mutually engaged with an inner wall of the inner cavity of the winding drum  1 , such that the insertion end  440  and the winding drum  1  are relatively fixed in a circumferential direction. The insertion end  440  forms a limit piece  443  for being abutted against an outer end surface of the winding drum  1 . The depth of the insertion end  440  being inserted into the winding drum  1  can be effectively controlled by setting the limit piece  443 . The connection shaft  442  and the middle shaft  40  correspondingly achieve the shaft connection. In the embodiment, by dividing the pivot  44  into the insertion end  440  and the connection shaft  442 , it is more convenient to assemble the pivot  44  into the winding drum  1  and achieve circumferential fixing, and it is also convenient for the pivot  44  to realize the shaft connection through the connection shaft  442  and the middle shaft  40  for power transmission. 
     In an embodiment of the present invention, an end wall of an end of the middle shaft  40  facing the winding drum  1  defines a connection hole  400 . The connection shaft  442  is correspondingly inserted into the connection hole  400 . Cross sections of the connection hole  400  and the connection shaft  442  are matched and are non-circular, such as hexagonal, triangular, pentagonal, elliptical, or star-shaped. Through the non-circular cross-section design, the power transmission between the middle shaft  40  and the connection shaft  442  can be realized when the connection shaft  442  is inserted into the connection hole  400 , and the power loss is small. 
     In another embodiment of the present disclosure, an end wall of an end of the middle shaft  40  facing the winding drum  1  defines a connection hole  400 . The connection shaft  442  is correspondingly inserted into the connection hole  400 . A fixing pin  90  is inserted into the connection hole  400  through a sidewall of the middle shaft  40  and inserted into the connection shaft  442  to fixedly connect the connection shaft  442  and the middle shaft  40 , so that the shaft connection can also be realized, and the power transmission can be performed. 
     In an embodiment of the present invention, the frame  3  defines a round hole  36 . An end of the middle shaft  40  is cylindrical and is inserted into the round hole  36 , and an end wall of the end of the middle shaft  40  inserted into the round hole  36  defines an operation hole  402  with a non-circular cross section. By exposing the end wall of the middle shaft  4  through the round hole  36  of the frame  3 , and defining the operation hole  402  with the non-circular cross section in the end wall of the middle shaft  4 , the rotation of the middle shaft can be driven by inserting a tool into the operation hole  402  when necessary, to realize the pre-winding operation of the plane scroll spring  42 . 
     In another embodiment of the present invention, the insertion end  440  of the pivot  44  is a hollow tube and only opens at an end adjacent to the connection shaft  442 . The connection shaft  442  is inserted into the tube. Cross sections of the connection shaft  442  and an inner tube hole  441  of the tube are matched and are non-circular, such as hexagonal, triangular, pentagonal, elliptical, or star-shaped. Through the non-circular cross-section design, the power transmission between the insertion end  440  and the connection shaft  442  can be realized when the connection shaft  442  is inserted into the tube, and then the insertion end  440  drives the winding drum to rotate. Moreover, this connection method has low loss during power transmission. 
     In a further embodiment of the present invention, a wall of the tube defines a plurality of slots  445  extending through the wall of the tube and extending along an axial direction of the tube. The connection shaft  442  correspondingly forms a plurality of hooks  446  engaged in the corresponding slots  445 . A compressed spring  444  is arranged in the tube and resiliently abutted against the end of the connection shaft  442  inserted into the tube. In the embodiment, by the cooperation of the hooks  446  and the slots  445 , and the pressing action of the compression spring  444 , the connection shaft  442  can be more stably inserted into the corresponding connection hole  400  of the middle shaft  40 . Moreover, when installing the roller shade, the connection shaft  442  can be pushed back into the tube by applying a force to the hooks  446  against a pushing force of the compression spring  444 , and the winding drum  1  can be assembled conveniently. When the pivot of the other end of the winding drum  1  is correspondingly inserted into a corresponding pivot hole, and the connection shaft  442  is aligned with the connection hole  400  of the middle shaft  40 , the force applied to the hooks  446  is cancelled, and the compression spring  444  acts to push the connection shaft  442  into the connection hole  400  of the middle shaft  40 . 
     In an alternative embodiment of the present invention, an inner wall of the winding drum  1  protrudes toward a center of the inner cavity  10  to form a protrusion  12 . An outer wall of the insertion end  440  of the pivot  44  correspondingly defines an insertion slot  447 . When the insertion end  440  is inserted into the inner cavity of the winding drum  1 , the protrusion  12  is correspondingly engaged in the insertion slot  447 , to realize the circumferential fixing. In a further embodiment, a position of an outer wall of the winding drum  1  corresponding to the protrusion  12  is depressed in to form a mounting slot  14  for fixing the end of the shade body, and a width of an opening of the mounting slot  14  is less than a slot width of the mounting slot  14 , thereby conveniently assembling the end of the shade body. 
     In the retracting or releasing operation of the roller shade using the roller shade actuation device of the present invention, the balance between the actuation force supplied by the original plane scroll spring  42 , and the weight of the shade body and the frictional resistance is broken by simply pulling down or pushing up the shade body, and the operation of releasing or retracting the shade body can be easily achieved. Moreover, when the shade body is driven to stay at any height position within the effective forming range, a new balance can be obtained between the actuation force provided by the plane scroll spring  42 , and the weight of the shade body and the frictional resistance, even if the force applied to the shade body is removed, and the curtain can still remain at this height. 
     The specific embodiments described above further explain the objectives, technical solutions, and beneficial effects of the present invention. It is to be understood that the foregoing description is only specific embodiments of the present invention, and is not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, improvements made within the spirit and scope of the present invention are intended to be included in the scope of the present invention.