Patent Publication Number: US-2004050125-A1

Title: Key-coupler for coupling key to key-holder

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001] This application is based upon and claims benefit of priority of Japanese Patent Application No. 2002-268594 filed on Sep. 13, 2002, the content of which is incorporated herein by reference.  
       BACKGROUND OF THE INVENTION  
       [0002] 1. Field of the Invention  
       [0003] The present invention relates to a key-coupler for coupling a key or keys to a key-holder.  
       [0004] 2. Description of Related Art  
       [0005] A double looped key-coupler as shown in FIG. 12A has been well known hitherto. The key-coupler  70  is made of a spring wire. One end of the spring wire forming the key-coupler  70  is opened to insert the key-coupler  70  into a hole  21  of a key  20 . Then, the key  20  is turned along the loop of the key-coupler  70  to be coupled therewith. The key coupler  70  may be further coupled with a key-holder (not shown), so that the key  20  is coupled to the key-holder via the key-coupler  70 . Plural keys  20  may be similarly coupled to the key-holder.  
       [0006] Another well known key-coupler is shown in FIG. 12B. The key-coupler  80  is made in a triangular shape that has an opening. To couple the key-coupler  80  with the key  20 , the opening of the key-coupler is forcibly opened, and the key  20  is inserted through the opening. Then, the opening of the key-coupler is forcibly closed again to keep the key  20  coupled with the key-coupler  80 . The key-coupler  80  may be further coupled with a key holder (not shown) so that the key  20  is coupled with the key-holder via the key-coupler  80 .  
       [0007] It is not so easy to couple or uncouple the key  20  with those conventional key-couplers  70 ,  80 . In the double looped key-coupler  70 , one end of the spring wire has to be forcibly opened against a spring action of the spring wire to couple the key  20  with the key-coupler  70 . Then, the key  20  has to be rotated along the loop of spring wire. If coupling and uncoupling the key  20  with the key-coupler  70  are repeated many times, the spring action of the key-coupler  70  may be deteriorated, and the key-coupler  70  may become not to properly function. Further, in case the key  20  is made of a soft material such as resin, the key  20  may be damaged by the end of the spring wire. In the case of the key-coupler  80  shown in FIG. 12B, a tool may be required to open or close it because it is usually too hard to manually deform the key-coupler  80 .  
       SUMMARY OF THE INVENTION  
       [0008] The present invention has been made in view of the above-mentioned problem, and an object of the present invention is to provide an improved key-coupler that is easily coupled or uncoupled with a key or keys.  
       [0009] The key-coupler according to the present invention includes a first closed ring and a second closed ring. A key or keys are connected to the second closed ring, for example, and a key-holder is connected to the first closed ring. Thus, the key or keys are coupled to the key-holder via the key-coupler. It is most preferable to make the key-coupler integrally from a single spring wire. The first closed ring is formed by overlapping a pair of circular portions, each having an opening that is closed with the other circular portion when circular portions are overlapped. The pair of the circular portions are connected to each other with a connecting portion. The second closed ring surrounded by the connecting portion is also formed when the pair of circular portions are overlapped.  
       [0010] By separating one circular portion from the other circular portion, both of the first and the second closed rings are opened at the same time. Upon opening the rings, a key or keys are inserted into the second closed ring, and the key-holder is inserted into the first closed ring. By releasing the separating force, both rings are closed due to a spring-back action of the spring wire that forms the key-coupler. Thus, the key or keys are coupled to the key-holder via the key-coupler. To remove the key from the key-coupler, both rings are opened by separating one circular portion from the other. A small gap may be formed between the pair of circular portions, so that the overlapped pair of circular portions are easily separated by pushing a back of a key against the small gap.  
       [0011] A key or keys are easily coupled or uncoupled with a key-holder via the key-coupler according to the present invention. The key-coupler is easily opened or closed by simply separating one circular portion from the other, and the key-coupler can be repeatedly used for a long time without being deformed. Other objects and features of the present invention will become more readily apparent from a better understanding of the preferred embodiment described below with reference to the following drawings. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0012] FIGS.  1 A- 1 D are a front view, a top view, a rear view and a left-side view, respectively, showing a key-coupler according to the present invention;  
     [0013]FIGS. 2A and 2B are cross-sectional views showing the key-coupler, taken along lines IIA-IIA and IIB-IIB, respectively, shown in FIG. 1B;  
     [0014] FIGS.  3 A- 3 C are perspective views showing the key-coupler, illustrating a process of coupling a key with a key-holder via the key-coupler;  
     [0015] FIGS.  4 A- 4 D are a front view, a top view, a rear view and a left-side view, respectively, showing a modified form  1  of the key-coupler;  
     [0016]FIGS. 5A and 5B are cross-sectional views showing the modified form  1 , taken along lines VA-VA and VB-VB, respectively, shown in FIG. 4B;  
     [0017] FIGS.  6 A- 6 D are a front view, a top view, a rear view and a left-side view, respectively, showing a modified form  2  of the key-coupler;  
     [0018]FIGS. 7A and 7B are cross-sectional views showing the modified form  2 , taken along lines VIIA-VIIA and VIIB-VIIB, respectively, shown in FIG. 6B;  
     [0019] FIGS.  8 A- 8 D are a front view, a top view, a rear view and a left-side view, respectively, showing a modified form  3  of the key-coupler;  
     [0020]FIGS. 9A and 9B are cross-sectional views showing the modified form  3 , taken along lines IXA-IXA and IXB-IXB, respectively, shown in FIG. 8B;  
     [0021] FIGS.  10 A- 10 D are a front view, a top view, a rear view and a left-side view, respectively, showing a modified form  4  of the key-coupler;  
     [0022]FIGS. 11A and 11B are cross-sectional views showing the modified form  4 , taken along lines XIA-XIA and XIB-XIB, respectively, shown in FIG. 10B; and  
     [0023]FIG. 12A is a perspective view showing a conventional key-coupler; and  
     [0024]FIG. 12B is a perspective view showing another conventional key-coupler.  
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
     [0025] A preferred embodiment of the present invention will be described with reference to FIGS.  1 A- 1 D,  2 A- 2 B and  3 A- 3 C.  
     [0026] First referring to FIGS.  1 A- 1 D and  2 A- 2 B, a structure of a key-coupler  10  will be described. Front, top, rear and left-side views of the key-coupler  10  are shown in FIGS.  1 A- 1 D, respectively, but bottom and right-side views are not shown because the bottom view is the same as the top view and the right-side view is the same as the left-side view.  
     [0027] The key-coupler is made of a single spring wire having a diameter of 1 mm. The key-coupler  10  is composed of a first circular portion  11 , a second circular portion  12  and a connecting portion  13  (better understood from FIG. 3B). A first closed ring  10   a  is formed by overlapping the first circular portion  11  on the second circular portion  12 . A second closed ring  10   b  is also formed when the first and the second circular portions  11 ,  12  are overlapped. The second closed ring  10   b  is partially encircled with the connecting portion  13  and positioned between the first closed ring  10   a  and the connecting portion  13  (better seen in FIG. 1B).  
     [0028] The first circular portion  11  is formed in a circular shape having a first opening  11   a , and the second circular portion  12  is formed in the same circular shape having a second opening  12   a . Both openings  11   a ,  12   a  are positioned symmetrically with respect to a center line IIA-IIA (shown in FIG. 1B) when both circular portions  11 ,  12  are overlapped. In forming the first circular portion  11 , one end of the spring wire is wound counter-clockwise by 315°. The second circular portion  12  is formed by winding the other end of the spring wire clockwise by 315°.  
     [0029] The first opening  11   a  is closed by the second circular portion  12  and the second opening  12   a  is closed by the first circular portion  11  when both circular portions  11 ,  12  are overlapped. Thus, the first closed ring  10   a  is formed. The second closed ring  10   b  encircled with the connecting portion  13  is also formed when the first and the second circular portions are overlapped.  
     [0030] When the first and the second circular portions are forcibly separated, the first and the second openings  11   a ,  12   a  are opened, and thus the first closed ring  10   a  are opened. The second closed ring  10   b  is also opened at the same time when the first and the second circular portions are separated. When the force forcibly separating both circular portions  11 ,  12  is released, both the circular portions  11 ,  12  return to their initial positions by the spring-back force of the spring wire, thereby contacting each other. Thus, the first closed ring  10   a  and the second closed ring  10   b  are formed again.  
     [0031] Now, referring to FIGS.  3 A- 3 C, a process of coupling a key  20  with a key-holder  25  via the key-coupler  10  will be described. The key-coupler  10 , to which no external force is applied and nothing is connected, is shown in FIG. 3A. The first circular portion  11  and the second circular portion  12  are forcibly separated from each other as illustrated in FIG.  3 B with exaggeration. That is, by applying external force, the first closed ring  10   a  and the second closed ring  10   b  are opened at the same time. A key  20  (or plural keys) is coupled in the second closed ring  10   b  by inserting the key  20  through the opening between both circular portions  11 ,  12 . A key-holder  25  (or a key-holder ring) is similarly coupled in the first closed ring  10   a . By releasing the force forcibly separating the circular portions  11 ,  12 , the key-coupler  10  returns to its original shape by its spring-back force, as illustrated in FIG. 3C. The key  20  may be coupled with the second closed ring  10   b  by connecting a hole  21  of the key  20  to the second closed ring  10   b . Thus, the key  10  (or keys) is coupled with the key-holder  25  via the key-coupler  10 .  
     [0032] The key-coupler  10  described above is easily opened by separating the first circular portion  11  from the second circular portion  12 , and the key  20  and the key-holder  25  can be easily engaged with the second closed ring  10   b  and the first closed ring  10   a , respectively. It is not necessary to turn the key  20  after it is inserted into the key-coupler  10 . By simply releasing the separating force, the key-coupler  10  returns to its original shape by its own spring-back force, thereby surely holding the key  20  in the second closed ring  10   b  and the key-holder  25  in the first closed ring  10   a.    
     [0033] The key  20  and the key-holder  25  are easily disconnected from the key-coupler  10  by simply separating the first circular portion  11  from the second circular portion  12 . In addition, since the first closed ring  10   a  and the second closed ring  10   b  are positioned on the substantially same plane, the key-coupler  10  can be made thin and compact in size.  
     [0034] The present invention is not limited to the embodiment described above, but it may be variously modified. Some modified forms will be described below. A key-coupler  30  as a modified form  1  is shown in FIGS.  4 A- 4 D and  5 A- 5 B. In the modified form  1 , a first closed ring  30   a  is formed in a triangular shape having round corners (changed from a circle shape) as shown in FIG. 4B. Other structures and functions of the modified form  1  are the same as those of the key-coupler  10  described above. Reference numbers used in the key-coupler  10  correspond to reference numbers used in the modified form  1  as follows: key-coupler  10 → 30 ; first circular portion  11 → 31 ; second circular portion  12 → 32 ; first closed ring  10   a → 30   a ; second closed ring  10   b → 30   b ; first opening  11   a → 31   a ; second opening  12   a → 32   a ; and connecting portion  13 → 33 .  
     [0035] A key-coupler  40  as a modified form  2  is shown in FIGS.  6 A- 6 D and  7 A- 7 B. In this modified form  2 , a first closed ring  40   a  is formed in a triangular shape having round corners (same as the modified form  2 ) as shown in FIG. 6B. In addition, a second closed ring  40   b  is shaped in a trapezoidal shape (changed from a round shape). Other structures and functions of the modified form  2  are the same as those of the key-coupler  10  described above. Reference numbers used in the key-coupler  10  correspond to reference numbers used in the modified form  2  as follows: key-coupler  10 → 40 ; first circular portion  11 → 41 ; second circular portion  12 → 42 ; first closed ring  10   a → 40   a ; second closed ring  10   b → 40   b ; first opening  11   a → 41   a ; second opening  12   a → 42   a ; and connecting portion  13 → 43 .  
     [0036] A key-coupler  50  as a modified form  3  is shown in FIGS.  8 A- 8 D and  9 A- 9 B. In this modified form  3 , a first circular portion  51  is formed to include an angled portion  51   b , and a second circular portion  52  is formed to include an angled portion  52   b . As better seen in FIG. 8D, both angled portions  51   b ,  52   b  form a gap  50   c  therebetween when both circular portions  51  and  52  are overlapped with each other. Since the gap  50   c  is formed in this modified form  3 , the circular portions  51 ,  52  can be easily opened by simply pushing a back of the key  20  against the gap  50   c . Therefore, the key  20  is easily coupled with the key-coupler  50 . The key-holder  25  can be easily coupled with the key-coupler  50  in the same manner.  
     [0037] Other structures and functions of the modified form  3  are the same as those of the key-coupler  10  described above. Reference numbers used in the key-coupler  10  correspond to reference numbers used in the modified form  3  as follows: key-coupler  10 → 50 ; first circular portion  11 → 51 ; second circular portion  12 → 52 ; first closed ring  10   a → 50   a ; second closed ring  10   b → 50   b ; first opening  11   a → 51   a ; second opening  12   a → 52   a ; and connecting portion  13 → 53 .  
     [0038] A key-coupler  60  as a modified form  4  is shown in FIGS.  10 A- 10 D and  11 A- 11 B. This modified form  4  is similar to the modified form  3  described above except for the position of a gap  60   c . In the modified form  3  described above, the gap  50   c  is positioned at a side opposite to the second closed ring  50   b . In this modified form  4 , a gap  60   c  is positioned at a side facing the second closed ring  60   b , as better seen in FIG. 10D. A first circular portion  61  is formed to include an angled portion  61   b , and a second circular portion  62  is formed to include an angled portion  62   b . As shown in FIG. 10D, both angled portions  61   b ,  62   b  form a gap  60   c  therebetween when both circular portions  61  and  62  are overlapped with each other. Since the gap  60   c  is formed, the circular portions  61 ,  62  can be easily opened by simply pushing a back of the key  20  against the gap  60   c . Therefore, the key  20  coupled to the key-coupler  60  is easily removed therefrom. Also, the key-holder  25  coupled to the key-coupler  60  can be easily separated therefrom in the same manner.  
     [0039] Other structures and functions of the modified form  4  are the same as those of the key-coupler  10  described above. Reference numbers used in the key-coupler  10  correspond to reference numbers used in the modified form  4  as follows: key-coupler  10 → 60 ; first circular portion  11 → 61 ; second circular portion  12 → 62 ; first closed ring  10   a → 60   a ; second closed ring  10   b → 60   b ; first opening  11   a → 61   a ; second opening  12   a → 62   a ; and connecting portion  13 → 63 .  
     [0040] The present invention is not limited to the embodiment and its modified forms described above, but it may be further modified. For example, the key  20  may be coupled with the first closed ring  10   a  instead of the second closed ring  10   b . Similarly, the key-holder  25  may be coupled with the second closed ring  10   b . In this manner, the key  20  (or keys) is coupled with the key-holder  25  via the key-coupler  10 . Though the key-coupler is integrally made of a single spring wire in the embodiment described above, the key-coupler can be made by connecting the first and the second circular portions, which are separately made, with the connecting portion made of a spring material.  
     [0041] While the present invention has been shown and described with reference to the foregoing preferred embodiment and its modified forms, it will be apparent to those skilled in the art that changes in form and detail may be made therein without departing from the scope of the invention as defined in the appended claims.