Abstract:
This patent application relates to spectacles or spectacle frames with intertwining helix joints and a nose pad portion to facilitate an interchanging of lenses of the spectacles. The helix joint allows the temples to move into a folded position. The nose pad portion provides an access portion for detaching and/or attaching the lenses.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present invention claims the benefits and advantages of U.S. provisional application Ser. No. 62/132,539, filed on Mar. 13, 2015, entitled “SPECTACLE FRAME WITH INTERTWINING HELIX JOINTS AND NOSE PAD STRUCTURE TO FACILITATE INTERCHANGING OF LENSES”, of which is herein incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present application relates to a spectacle frame, and in particular to intertwining helix joints connecting a front part and temples of the frame. It also relates to a spectacle frame with a nose pad structure that facilitates interchanging of lenses. 
     BACKGROUND 
     A spectacle temple joint fulfills several requirements. It allows a temple to be moved between a folded position for storage and an open position for wearing by a user. A common type of joint has a “door hinge” type of mechanism. It includes a pin for connecting two hinge halves, each of which is attached to a spectacle frame by screws or rivets. A common type of spectacle frame for holding lenses has a complete geometry, such as a complete circle or a complete rectangle. 
     In addition, two nose pads extend rearwards from the front of the frame for resting on the nose of a wearer when the spectacle frame is being worn. The common type of nose pad made of soft materials is usually fixed on a metal bracket by a screw. The bracket is further connected to the front of the frame by a thin wire. 
     In the above construction of joints and nose pads, there are many parts to manufacture and things may go wrong. The screws would become loose and could be lost. It also involves labor intensive assembling procedures. 
     Lenses are commonly fixed on a spectacle frame either by embedding them in grooves formed on the front of the frame or by holding them with wires. However, both methods make it hard for a user to detach the lenses without tools and undermine the potential of interchanging different lenses, such as prescription lenses and tinted lenses, on the same frame. 
     SUMMARY OF THIS DISCLOSURE 
     One of the objectives of the spectacle frame disclosed in the present application is to provide a joint that is simple, reliable and adaptable. It should also be easy to manufacture and maintain. 
     This objective can be achieved by an intertwining helix joint which connects temples and a front portion of a spectacle frame. The joint may include two intertwining helixes with different sectional profiles. The two intertwining helixes do not touch each other but leave a space in-between. Smaller sectional profile of the helixes at an inner side leaves more space between them and thus allows the temples to be bent 90 degrees inward to a folded position for easy storage, while larger sectional profile of the helixes at an outer side leaves less space between them and thus provides a firm stop at an open position. The intertwining helix joint can exert a small amount of force on a wearer&#39;s head which helps to secure a spectacle in place. 
     Besides, the temple can be bent in all directions, making it adaptable to features on the face of a wearer, such as levels of the ears and nose, which are slightly different for different people. 
     Another objective of the spectacle frame disclosed in the present application is to provide a nose pad structure that is robust and a frame with easily interchangeable lenses. 
     This objective can be achieved by one single feature, namely a bent portion at the front of the frame which can also serve as a nose pad. It is a continuation of the frame and contains no small parts. The bent portion renders the front of the frame incomplete, leaving an access space for easily detaching and attaching lenses by hands without any tools. 
     The spectacle frame can be manufactured in one monolithic construction. Its complex geometries cannot be made by conventional manufacturing methods such as plastic injection molding or hand making from acetate sheet. However, it can be manufactured by additive manufacturing (3D Printing) technique with flexible materials such as plastic or any other suitable materials. 
     The spectacle frame disclosed in the present application makes eyeglasses comfortable to wear, become reliable and multi-functional. 
     In addition, with an online sales platform, users are able to specify the total width of an eyewear, the length of the temples and the size of the nose pads. The resultant frame can be 3D printed in one monolithic construction with all the chosen features incorporated. 
     This bespoke eyewear appeals to those who demand a high level of comfort which cannot be satisfied by conventional off-the-shelf frames with one standard size. They include users with atypical facial features, contact lens users who are not satisfied with the comfort level of conventional eyewear, or young children. It is also suitable for those who are looking for a personalized item for themselves or a gift for someone else. 
     It fills the gap of the kid&#39;s eyewear market. There are small-sized spectacles to choose from the online sales platform. There are no small loose parts, and thus are safe for children. 
     The spectacle frame disclosed in the present application can benefit the eyewear industry by introducing a completely new manufacturing method (i.e. 3D Printing), and a new business model (i.e. 3D Printed-to-order) to the eyewear industry. This can lower the initial capital input and thus the risk of product development since no inventory is required. It can encourage smaller to medium-sized product design enterprises to develop and retail their products. 
     The marketability of the spectacle frame is very high because fully functional prototypes have been successfully produced. The manufacturing cost is also viable to achieve reasonable profits by retail at a price range competitive to conventional eyewear. 
     Although the spectacle frame and the spectacle are shown and described with respect to certain embodiments, it is obvious that equivalents and modifications will occur to others skilled in the art upon the reading and understanding of the specification. The spectacle frame in the present application includes all such equivalents and modifications, and is limited only by the scope of the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Specific embodiments of the spectacle frame will now be described by way of example with reference to the accompanying drawings wherein: 
         FIG. 1  is a front perspective view of a spectacle frame with intertwining helix joints and a nose pad structure according to an embodiment disclosed in the present application. 
         FIG. 2  is a rear perspective view of the spectacle frame of  FIG. 1 . 
         FIG. 3  is a front view of the spectacle frame of  FIG. 1 . 
         FIG. 4  is a side view of the spectacle frame of  FIG. 1 . 
         FIG. 5  shows two further embodiments of the intertwining helix joint having an increasing or decreasing number of turn of the helix. 
         FIG. 6  shows three further embodiments of the intertwining helix joint having different sizes of circular cross section at different portions of the helixes. 
         FIG. 7  shows two further embodiments of the intertwining helix joint having an increasing or decreasing total number of helix. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1-4  show different views of an embodiment of a spectacle frame. The spectacle frame may include a front portion  101  and two temples  102  which are connected to the front portion  101  by two intertwining helix joints  103  respectively, so that the two temples  102  can be moved between a folded position (not shown) for storage and an open position as shown in  FIGS. 1 and 2 . 
     The front portion  101  may include an upper rim  12  portion and a lower rim portion  13 . The upper rim portion  12  may include a left portion  121  conforming in shape with an upper edge of a left lens, a right portion  123  conforming in shape with an upper edge of a right lens, and a middle bridge portion  122  extending between the left and right portions of the upper rim portion  12 . 
     Similarly, the lower rim portion  13  may include a left portion  131  conforming in shape with a lower edge of the left lens, a right portion  133  conforming in shape with a lower edge of the right lens, and a middle nose pad portion  132  extending between the left and right portions of the lower rim portion  13 . 
     The middle nose pad portion  132  may include a middle bridge-abutting portion  134  configured to abut against the middle bridge portion  122  of the upper rim portion  12 , and two spaced-apart bent portions  104  extending between two inner ends of the left and right portions of the lower rim portions  13  and two opposite ends of the middle bridge-abutting portion  134  respectively. The two bent portions  104  are in the form of two rearward extending projections defining two nose-engaging surfaces that are adapted to rest on the two sides of the nose of a wearer when the spectacle is being worn. The two bent portions  104  expose portions of the edges of the lenses and create an access space about the size of a fingertip, making it easy to detach the lens and attach another one on the frame. 
     Conventional grooves may be formed on the inner sides of the upper and lower rim portions of the front portion  101  for positioning and holding the lenses on the frame. 
     Each temple  102  may include elongate upper and lower portions. The two rear ends of the elongate upper and lower portions of each temple  102  may be formed into a round loop  105 . The two front end portions of the elongate upper and lower portions of each temple  102  may be provided with a joint  103  in the form of two intertwining helixes. 
     As a result, the temples  102  can be bent in 90 degrees at all directions. This renders the spectacles to adapt to facial features of the wearer. 
     Two generally L-shaped portions may extend between the two outer ends of the upper and lower rim portions and the two front ends of the two intertwining helixes of the joint  103  of each temple  102  respectively. 
     The front portion  101 , the temples  102  with the joints  103 , and the nose pad  104  may be made by additive manufacturing (3D Printing) technique as one monolithic piece using flexible materials such as plastic or any other suitable materials. 
     Although it has been shown that the helixes of the joints  103  have circular sectional profile, it is understood by one skilled in the art that the helixes of the joints  103  can have other possible sectional profiles such as oval, rectangular, polygon, etc. 
       FIG. 5  shows two further embodiments of the intertwining helix joint having an increasing or decreasing number of turn of the helix. 
     One further embodiment of the intertwining helix joint is designated by reference numeral  106 , as shown in the first drawing. It can be seen that this intertwining helix joint  106  has one less helical turn as compared with the embodiment of the intertwining helix joint  103  depicted in  FIG. 4 . 
     Another further embodiment of the intertwining helix joint is designated by reference numeral  107 , as shown in the second drawing. It can be seen that this intertwining helix joint  107  has one more helical turn as compared with the embodiment of the intertwining helix joint  103  depicted in  FIG. 4 . 
     Although it has been shown and described that there are about 5-7 turns in the intertwining helix joint  103 ,  106 ,  107 , it is appreciated by one skilled in the art that the intertwining helix joint may have any number of turns. 
       FIG. 6  shows three further embodiments of the intertwining helix joint having different sizes of circular cross section at different portions of the helixes. 
     One further embodiment of the intertwining helix joint is designated by reference numeral  109 , as shown in the first drawing. It can be seen that this intertwining helix joint  109  has a helically turning portion  110  with a smaller sectional profile. 
     Another further embodiment of the intertwining helix joint is designated by reference numeral  111 , as shown in the second drawing. It can be seen that this intertwining helix joint  111  has a plurality of helically turning portions  112 ,  113  with a smaller sectional profile. 
     Yet another further embodiment of the intertwining helix joint is designated by reference numeral  114 , as shown in the third drawing. It can be seen that this intertwining helix joint  114  has helically turning portions  115  with a larger sectional profile disposed at the inner side of the joint  114 . 
     Although it has been shown and described that the helically turning portions with smaller circular sectional profile are formed at the rear or inner side of the intertwining helix joint, it is contemplated by one skilled in the art that the helically turning portions with smaller circular sectional profile can be formed at any suitable portions of the intertwining helix joint. The sectional profile may be circular or in any other appropriate shapes. Furthermore, the intertwining helix joint may have any suitable sizes, such as length, height and width. 
       FIG. 7  shows two further embodiments of the intertwining helix joint having an increasing or decreasing total number of helix. 
     The first drawing in  FIG. 7  shows a joint  116  having only one helix. The other helix is replaced by a straight elongated portion having a smaller sectional profile. The straight elongated portion may be disposed along a central axis of the single helix. The second drawing shows a joint having three intertwining helixes. It can be seen that spaces are formed between the three intertwining helixes to facilitate bending of the temple of the spectacle frame. 
     Although it has been shown and described that there are 1-3 intertwining helixes in a joint, it is understood by one skilled in the art that the joint may have any number of helixes. 
     While the spectacle frame has been shown and described with particular references to a number of preferred embodiments thereof, it should be noted that various other changes or modifications may be made without departing from the scope of the appended claims.