Patent Publication Number: US-11395533-B2

Title: Jewelry box

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is the U.S. National Phase under 35 U.S.C. § 371 of International Application No. PCT/JP2018/017745, filed on May 8, 2018, the entire contents is hereby incorporated by reference. 
     TECHNICAL FIELD 
     The present invention relates to a jewelry box comprising a lower box component and an upper box component coupled to the lower box component through a hinge for swinging movement between an opened position and a closed position. 
     BACKGROUND ART 
     Japanese Patent Application No. 2005-245912 and Japanese Patent No. 4625409 respectively disclose an accessary box comprising a lower box component supporting a jewelry such as a ring, and an upper box component coupled to the lower box component through a hinge for swinging movement between an opened position and a closed position. The upper box component is configured to close the lower box component at the closed position to cover the jewelry and to open the lower box component at the opened position to expose the jewelry. An electric lamp is attached to the upper box component so as to emit a visible light toward the jewelry. A switch is connected to the electric lamp. The switch is configured to establish the supply of electric current when the upper box component swings to open the lower box component, and to break the supply of electric current when the upper box component is positioned at the closed position. 
     CITATION LIST 
     Patent Literature 
     Japanese Patent Application No. 2005-245912 
     Japanese Patent No. 4625409 
     SUMMARY OF THE INVENTION 
     Technical Problem 
     A normal electric lamp is utilized to emit a visible light toward the accessary supported on the lower box component in Japanese Patent Application No. 2005-245912 and Japanese Patent No. 4625409. And under normal circumstances, the natural light and a visible light from lamps fully surround the accessary box, so that the electric lamp cannot sufficiently achieve any visual performance resulting in a dramatic impact as expected. 
     It is accordingly an object of the invention to provide a jewelry box sufficiently generating a visual performance resulting in a dramatic impact on one who opens the jewelry box. 
     Solution to Problem 
     According to a first aspect of the invention, there is provided a jewelry box comprising: a lower box component; a diamond supported in the lower box component, the diamond having a blue fluorescence; an upper box component coupled to the lower box component through a hinge for swinging movement between an opened position and a closed position, the upper box component configured to close the lower box component at the closed position to cover the diamond and to open the lower box component at the opened position to expose the diamond; and a light source supported on the lower box component or the upper box component, the light source configured to emit ultraviolet radiation to the diamond after the upper box component is opened from the closed position. 
     According to a second aspect of the invention, in addition to the features of the first aspect, the light source is configured to emit radiation other than visible light. 
     According to a third aspect of the invention, in addition to the features of the second aspect, the light source has a directivity allowing entire radiation to be blocked with the lower box component and the upper box component. 
     According to a fourth aspect of the invention, there is provided a jewelry box comprising: a lower box component; a diamond supported in the lower box component, the diamond having a blue fluorescence; an upper box component coupled to the lower box component through a hinge for swinging movement between an opened position and a closed position, the upper box component configured to close the lower box component at the closed position to cover the diamond and to open the lower box component at the opened position to expose the diamond; and a light source supported on the lower box component or the upper box component, the light source configured to emit ultraviolet radiation to the diamond when a predetermined time has elapsed after the upper box component reaches the opened position. 
     According to a fifth aspect of the invention, in addition to the features of the fourth aspect, the light source is configured to emit radiation other than visible light. 
     According to a sixth aspect of the invention, in addition to the features of the fifth aspect, the light source has a directivity allowing entire radiation to be blocked with the lower box component and the upper box component. 
     According to a seventh aspect of the invention, there is provided a jewelry box comprising: a lower box component; a diamond supported in the lower box component, the diamond having a blue fluorescence; an upper box component coupled to the lower box component through a hinge for swinging movement between an opened position and a closed position, the upper box component configured to close the lower box component at the closed position to cover the diamond and to open the lower box component at the opened position to expose the diamond; and a light source supported on the lower box component or the upper box component, the light source configured to emit ultraviolet radiation to the diamond with an incremental intensity of the ultraviolet radiation after the upper box component reaches the opened position. 
     According to a eighth aspect of the invention, in addition to the features of the seventh aspect, the light source is configured to emit radiation other than visible light. 
     According to a ninth aspect of the invention, in addition to the features of the eighth aspect, the light source has a directivity allowing entire radiation to be blocked with the lower box component and the upper box component. 
     Advantageous Effects of Invention 
     According to the first aspect, when the upper box component is operated to at least swing from the closed position, the ultraviolet radiation is emitted toward the diamond. The diamond shines blue. The blue diamond happens to appear in the sight of one who observes the diamond. Since the blue diamond is unfamiliar, the diamond shining blue generates a dramatic impact on one who opens the jewelry box. When the diamond is picked out of the jewelry box, the diamond shines clear and white (transparent) under a visible light (the natural light or from a normal electric lamp). A sequential radiation of ultraviolet light and a visible light achieves a visual performance including a change in the color of the diamond. This type of visual performance generates a dramatic impact on one who observes the jewelry box. 
     According to the second aspect, since the light emitted from the light source is invisible to one who observes the diamond, the blue diamond predominates in the background, so that the dramatic impact is enhanced. 
     According to the third aspect, one who observes the jewelry box only catches a blue visible light transformed from the ultraviolet light based on the blue fluorescence of the diamond, and the ultraviolet light does not leak out of the jewelry box. The eyes of one who observes the jewelry box is prevented from suffering from an influence of the ultraviolet radiation. 
     According to the fourth aspect, when the upper box component reaches the opened position, the diamond is exposed out of the jewelry box. The diamond shines clear and white (transparent) under a visible light (the natural light or from a normal electric light). When a predetermined time has elapsed after the upper box component reaches the opened position, the ultraviolet radiation is emitted from the light source toward the diamond. The color of the diamond changes from clarity to blue. A visual performance is in this manner accomplished in response to the opening action of the jewelry box. This type of visual performance generates a dramatic impact on one who observes the jewelry box. 
     According to the fifth aspect, since the light emitted from the light source is invisible to one who observes the diamond, the blue diamond predominates in the background, so that the dramatic impact is enhanced. 
     According to the sixth aspect, one who observes the jewelry box only catches a blue visible light transformed from the ultraviolet light based on the blue fluorescence of the diamond, and the ultraviolet light does not leak out of the jewelry box. The eyes of one who observes the jewelry box is prevented from suffering from an influence of the ultraviolet radiation. 
     According to the seventh aspect, when the upper box component is operated to swing from the closed position, the diamond is exposed out of the jewelry box. The diamond shines clear and white (transparent) under a visible light (the natural light or from a normal electric light). When the upper box component reaches the opened position, the ultraviolet radiation is emitted from the light source toward the diamond. As the intensity of the ultraviolet radiation increases, the color of the diamond gradually changes from clarity to blue. A visual performance is in this manner accomplished in response to the opening action of the jewelry box. This type of visual performance generates a dramatic impact on one who observes the jewelry box. 
     According to eighth aspect, since the light emitted from the light source is invisible to one who observes the jewelry box, the blue diamond predominates in the background, so that the dramatic impact is enhanced. 
     According to the ninth aspect, one who observes the jewelry box only catches a blue visible light transformed from the ultraviolet light based on the blue fluorescence of the diamond, and the ultraviolet light does not leak out of the jewelry box. The eyes of one who observes the jewelry box is prevented from suffering from an influence of the ultraviolet radiation. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view illustrating the appearance of a jewelry box according to one embodiment of the invention. 
         FIG. 2  is a perspective view schematically illustrating the structure of the jewelry box when the upper box component is opened. 
         FIG. 3  is an enlarged perspective view schematically illustrating the structure of a hinge. 
         FIG. 4  is a sectional view at the vertical plane along the line  4 - 4  in  FIG. 1   
         FIG. 5  is a sectional view at the vertical plane along the line  5 - 5  in  FIG. 2 . 
         FIG. 6  is a circuit diagram of an electronic circuit according to a first example. 
         FIG. 7  is a circuit diagram of an electronic circuit according to a second example. 
         FIG. 8  is a circuit diagram of an electronic circuit according to a third example. 
         FIG. 9  is a circuit diagram of an electronic circuit according to a fourth example. 
     
    
    
     REFERENCE SIGNS LIST 
     
         
           11  . . . a jewelry box 
           12  . . . a lower box component 
           13  . . . an upper box component 
           23  . . . a diamond (diamond stone) 
           26  . . . a hinge 
           33  . . . a light source (LED lamp) 
       
    
     DESCRIPTION OF EMBODIMENTS 
     Embodiments of the present invention will be explained below with reference to the accompanying drawings. 
       FIG. 1  schematically illustrates a jewelry box  11  according to one embodiment of the present invention. The jewelry box  11  includes a lower box component  12  and an upper box component  13  placed on the lower box component  12  to form a rectangular parallelepiped box in combination with the lower box component  12 . The lower box component  12  comprises a hard molded resin body having a bottom plate  14   a  shaped in a rectangle or square and four side walls  14   b  respectively standing at right angles from four sides of the bottom plate  14   a , and a covering paper  15  adhered to the outer surfaces of the hard molded resin body so as to decorate the hard molded resin body. The upper box component  13  comprises a hard molded resin body having a top plate  16   a  shaped in a rectangle or square and four side walls  16   b  respectively extending downward from four sides of the top plate  16   a  to mate their lower ends with the upper end of the corresponding side walls  14   b  of the lower box component  12 , and a covering paper  17  adhered to the outer surfaces of the hard molded resin body so as to decorate the hard molded resin body. The lower ends of the side walls  16   b  mate with the corresponding upper ends of the side walls  14   b  of the lower box component  12  so as to form side walls of the jewelry box  11 . The covering papers  15 ,  17  may be a sueded paper, a cloth-like paper, or the like. 
     As depicted in  FIG. 2 , a cushioning material  18  is fitted in a space of rectangular parallelepiped surrounded by the side walls  14   b  of the lower box component  12 . The cushioning material  18  includes, for example, a sponge and a cloth  18   a  wrapping the sponge. A slit  19  is formed in the cushioning material  18 . A ring  21  is inserted into the slit  19 , for example. The elasticity of the cushioning material  18  serves to hold the ring  21  in the slit  19 . 
     The ring  21  includes an annular member  22  made from platinum having an inside diameter corresponding to the size of a finger, for example, and a diamond stone  23  fixed to the mount of the annular member  22 . The diamond stone  23  may be a single stone or a group of stones. The diamond stone  23  exhibits a blue fluorescence equal to or stronger than strong blue, namely, strong blue or very strong blue. The diamond stone  23  shines clear and white (transparent) under a visible light (the natural light or from a normal electric light). The diamond stone  23  shines blue under ultraviolet radiation. The diamond stone  23  is thus supported in the lower box component  12 . 
     A ceiling member  24  is fitted in a space of rectangular parallelepiped surrounded by the side walls  16   b  of the upper box component  13 . The ceiling member  24  includes a dressing top panel  24   a  shaped in a rectangle or square to form the ceiling surface of the jewelry box  11 , and four side lining panels  24   b  respectively continuous from four sides of the dressing top panel  24   a  to cover over the inside surfaces of the side walls  16   b . Here, the side lining panels  24   b  are not adhered to the inside surfaces of the side walls  16   b , and the ceiling member  24  is detachably set inside the upper box component  13 . 
     As depicted in  FIG. 3 , the upper box component  13  is coupled to the lower box component through a hinge  26  for swinging movement between an fully-opened position and a closed position. The hinge  26  includes a first hinge blade  27  overlaid and fixed on the inside surface of the side wall  16   b  of the upper box component  13 , a second hinge blade  28  overlaid and fixed on the inside surface of the corresponding side wall  14   b  of the lower box component  12 , and a single hinge pin  29 . The first hinge blade  27  has tubes  27   a . The second hinge blade  28  has tubes  28   a  alternated in series with the tubes  27   a  of the first hinge blade  27 . The hinge pin  29  is commonly inserted into the tubes  27   a  of the first hinge blade  27  and the tubes  28   a  of the second hinge blade  28 . The first hinge blade  27  swings around the hinge pin  29  relative to the second hinge blade  28 . 
     A plate spring  31  is connected to the hinge  26 . As depicted in  FIG. 4 , the plate spring  31  is formed in a bent plate keeping generatrices in parallel with the axis of the hinge pin  29 . The opposite ends of the plate spring  31  are respectively coupled to the first hinge blade  27  and the second hinge blade  28  at locations spaced from the hinge pin  29 . The first hinge blade  27  is positioned beside the second hinge blade  28  along a common provisional plane, and the intermediate section of the plate spring  31  gets furthest inward from the hinge pin  29 , when the upper box component  13  takes the closed position where the lower end of the upper box component  13  is mated with the upper end of the lower box component  12 . As the upper box component  13  displaces around the hinge pin  29  toward the closed position from the opened position, the outside angle reduces between the first hinge blade  27  and the second hinge blade  28  so that the intermediate section of the plate spring  31  gets closer to the hinge pin  29 . As depicted in  FIG. 5 , when the intermediate section of the plate spring  31  contacts with the hinge pin  29 , a further displacement of the upper box component  13  is restrained around the hinge pin  29  relative to the lower box component  12 . The contact of the plate spring  31  with the hinge pin  29  in this manner defines the closed position of the upper box component  13 . The plate spring  31  exerts the driving force to urge the upper box component  13  toward the closed position when the opening angle is smaller than a predetermined opening angle around the hinge pin  29  between the upper box component  13  and the lower box component  12 . The plate spring  31  exerts the driving force to urge the upper box component  13  toward the opened position when the opening angle is larger than the predetermined opening angle around the hinge pin  29  between the upper box component  13  and the lower box component  12 . A hinge cover  32  covers over the hinge  26  and the plate spring  31 . The hinge cover  32  may be made of a material identical to that of the cloth  18   a  of the cushioning material  18 , for example. 
     A light-emitting diode (LED) lamp (light source)  33  is embedded in the ceiling member  24  for the upper box component  13 . The LED lamp  33  is configured to emit ultraviolet radiation based on a predetermined directivity Dv. The LED lamp  33  emits a ultraviolet light of ultraviolet A having the wavelength ranging from 315 nm to 400 nm, for example. The LED lamp  33  is preferably configured to emit radiation other than visible light. The LED lamp  33  is preferably designed to have a narrower directivity Dv. The LED lamp  33  has the directivity Dv allowing entire radiation to be blocked with the lower box component  12 . 
     A battery  35  is connected to the LED lamp  33 . The battery  35  is contained in a battery chamber  34  is defined between the top plate  16   a  of the hard molded resin body and the dressing top panel  24   a . A thin button cell may be utilized as the battery  35 , for example. Here, the button cells are connected in series, for example. Electric current is supplied to the LED lamp  33  from the battery  35 . 
     A switch  36  is established in the hinge  26  and the plate spring  31 . The switch  36  is configured to control the supply of electric current to the LED lamp  33  and the termination of the electric current. A first contact  37  is fixed to the intermediate section of the plate spring  31 . The first contact  37  is insulated from the plate spring  31 . The hinge  26  function as a second contact establishing the switch  36  in combination with the first contact  37 . Accordingly, the hinge  26  is made of an electrically conductive material. An electrically conductive material such as copper (Cu) is used to form the first contact  37 , for example. An insulating material is interposed between the first contact  37  and the plate spring  31 , for example. The first contact  37  is placed on the plate spring  31  at the surface opposed to the hinge pin  29 . The first contact  37  contacts with the hinge  26  when the upper box component  13  takes the opened position. The first contact  37  is spaced apart from the hinge  26  when the upper box component  13  takes a position other than the opened position. 
     As depicted in  FIG. 6 , an electronic circuit  38  according to a first example, including the LED lamp  33 , the battery  35  and the switch  36 , is established in the jewelry box  11 . The LED element of the LED lamp  33  is connected in series with the battery  35  in the electronic circuit  38 . The switch  36  and a time-delay normally closed contact or relay  39  are connected in series with the LED lamp  33 . A timer  41  is connected in parallel with the LED lamp  33  and the normally closed contact  39 . When the switch  36  is closed, the LED lamp  33  lights up in response to the supply of electricity. The timer  41  starts operating concurrently with the close of the switch  36 . The normally closed contact  39  opens when a predetermined time period has elapsed after the close of the switch  36 . The LED lamp  33  thus blows out. When the switch  36  opens, the timer  41  returns to the initial status, and the LED lamp  33  blows out. 
     The LED lamp  33 , the normally closed contact  39  and the timer  41  may be mounted on a common printed circuit board, for example, in the electronic circuit  38 . Wires such as vinyl coated wires or cables may be utilized to electrically connect the first contact  37  of the switch  36 , the first hinge blade  37  or the second hinge blade  28 , the battery  35  and the like to wiring patterns on the printed circuit board. The printed circuit board may be contained within the battery chamber  34 , for example. 
     Next, the operation of the jewelry box  11  will be described below. As depicted in  FIG. 1 , when the upper box component  13  is located at the closed position, the lower end of the upper box component  13  is mated with the upper end of the lower box component  12 . The upper box component  13  covers over the ring  21  and buries the diamond stone  23 . One who observes the jewelry box  11  looks at the exterior of the closed jewelry box  11 . The diamond stone  23  is placed out of sight of one who observes the jewelry box  11 . 
     Here, as depicted in  FIG. 4 , the intermediate section of the plate spring  31  gets furthest from the hinge pin  29 . Accordingly, the first contact  37  of the switch  36  is spaced from the hinge  26  namely the second contact. The switch  36  opens in the electronic circuit  38 . 
     When one who observes the jewelry box  11  manipulate the upper box component  13  toward the opened position around the hinge pin  29  against the elasticity of the plate spring  31 , the lower end of the upper box component  13  gets remote from the upper end of the lower box component  12 . A visible light (the natural light and from a normal electric lamp) stream in through a gap between the upper box component  13  and the lower box component  12  toward the diamond stone  23 . The diamond stone  23  gradually appears in the sight of one who observes the jewelry box  11 . The diamond stone  23  is exposed to the radiation of the visible light. Accordingly, the diamond stone  23  shines clear and white. 
     The plate spring  31  exerts the driving force to urge the upper box component  13  toward the opened position when the opening angle is larger than the predetermined opening angle around the hinge pin  29  between the upper box component  13  and the lower box component  12 . The elasticity of the plate spring  31  serves to hold the upper box component  13  at the opened position. As depicted in  FIG. 2 , one who observes the jewelry box  11  is allowed to look at the diamond stone  23  without blockage of the upper box component  13 . 
     When the upper box component  13  reaches the opened position, as depicted in  FIG. 5 , the intermediate section of the plate spring  31  is urged against the hinge  26  with the elasticity of the plate spring  31 . The first contact  37  contacts with the hinge  26  namely the second contact. The switch  36  closes in the electronic circuit  38 . The LED lamp  33  comes to light up. The LED lamp  33  emits ultraviolet radiation toward the diamond stone  23 . The diamond stone  23  shines blue. 
     When the upper box component  13  swings from the closed position, the diamond stone  23  shining blue comes into the sight of one who observes the jewelry box  11 . Since a blue diamond is unfamiliar, the diamond stone  23  shining blue generates a dramatic impact on one who opens the jewelry box  11 . When the ring  21  is picked out of the jewelry box  11 , the diamond stone  23  shines clear and white (transparent) under a visible light (the natural light or from a normal electric lamp). A sequential radiation of ultraviolet light and a visible light achieves a visual performance including a change in the color of the diamond stone  23 . This type of visual performance generates a dramatic impact on one who observes the jewelry box  11 . 
     The timer  41  starts operating in the electronic circuit  38  in response to the close of the switch  36 . When the predetermined time period has elapsed after the upper box component  13  reaches the opened position, the normally closed contact  38  opens. The LED lamp  33  thus blows out. The color of the diamond stone  23  changes from blue to transparency (white) after the diamond stone  23  shining blue has been observed awhile subsequent to the opening of the upper box component  13 . When the upper box component  13  is closed from the opened position, the switch  36  opens and the LED lamp  33  blows out. 
     Here, the LED lamp  33  is configured to emit radiation other than visible light. Accordingly, the light emitted from the LED lamp  33  is invisible to one who observes the jewelry box  11 . The blue diamond stone  23  predominates in the background, so that the dramatic impact is enhanced. 
     The LED lamp  33  has the directivity Dv allowing the entire radiation to be blocked with the lower box component  12 . One who observes the jewelry box  11  only catches a blue visible light transformed from the ultraviolet light based on the blue fluorescence of the diamond stone  23 , and the ultraviolet light does not leak out of the jewelry box  11 . The eyes of one who observes the jewelry box  11  is prevented from suffering from an influence of the ultraviolet radiation. 
     A normally closed momentary switch (tact switch) may be employed in the electronic circuit  38  in place of the switch  36 . The momentary switch opens the contacts when the upper box component  13  is overlaid on the lower box component  12  at the closed position. When the upper box component  13  displaces from the closed position, the LED lamp  33  lights up after a predetermined time has elapsed corresponding to the stroke of the momentary switch. The diamond stone  23  shining blue comes to appear in the sight of one who observes the jewelry box  11  concurrent with the opening of the upper box component  13 . Since a blue diamond is unfamiliar, the diamond stone  23  shining blue generates a dramatic impact on one who opens the jewelry box  11 . When the diamond stone  23  is picked out of the jewelry box  11 , the diamond stone  23  shines clear and white (transparent) under a visible light (the natural light or from a normal electric lamp). A sequential radiation of ultraviolet light and a visible light achieves a visual performance including a change in the color of the diamond stone  23 . This type of visual performance generates a dramatic impact on one who observes the jewelry box  11 . 
       FIG. 7  schematically illustrates the structure of an electronic circuit  43  according to a second example. The LED element of the LED lamp  33  is connected in series with the battery  35  in the electronic circuit  43 . A time-delay normally open contact  44  is connected in series with the LED lamp  33 . The switch  36  and a timer  45  are connected in parallel with the LED lamp  33  and the normally open contact  44 . When the switch  36  is closed, the timer starts to operate, and the normally open contact  44  closes after a predetermined time has elapsed. The LED lamp  33  thus blows out. When the switch  36  opens, the timer  45  returns to the initial status, the normally open contact  44  opens. The LED lamp  33  thus blows out. 
     The LED lamp  33 , the normally open contact  44  and the timer  45  may be mounted on a common printed circuit board, for example, in the electronic circuit  43 . Wires such as vinyl coated wires or cables may be utilized to electrically connect the first contact  37  of the switch  36 , the first hinge blade  37  or the second hinge blade  28 , the battery  35  and the like to wiring patterns on the printed circuit board. The printed circuit board may be contained within the battery chamber  34 , for example. 
     When the upper box component  13  reaches the opened position, even though the switch  36  closes in the electronic circuit  43 , the LED lamp  33  is suspended from lighting until a predetermined time period elapses. As depicted in  FIG. 2 , one who observes the jewelry box  11  is allowed to look at the diamond stone  23  shining clear and white without blockage of the upper box component  13 . When the predetermined time period has elapsed after the close of the switch  36 , the LED lamp  33  lights up. The LED lamp  33  emits ultraviolet radiation toward the diamond stone  23 . The diamond stone  23  shines blue. The color of the diamond stone  23  changes from transparency (white) to blue after the diamond stone  23  shining clear and white has been observed awhile subsequent to the opening of the upper box component  13 . A visual performance is in this manner accomplished in response to the opening action of the upper box component  13 . This type of visual performance generates a dramatic impact on one who observes the jewelry box. When the switch  36  is opened, the LED lamp  33  blows out. 
     Here, the LED lamp  33  is configured to emit radiation other than visible light. Accordingly, the light emitted from the LED lamp  33  is invisible to one who observes the diamond stone  23 . The blue diamond stone  23  predominates in the background, so that the dramatic impact is enhanced. 
     The LED lamp  33  has the directivity Dv allowing the entire radiation to be blocked with the lower box component  12 . One who observes the jewelry box  11  only catches a blue visible light transformed from the ultraviolet light based on the blue fluorescence of the diamond stone  23 , and the ultraviolet light does not leak out of the jewelry box  11 . The eyes of one who observes the jewelry box  11  is prevented from suffering from an influence of the ultraviolet radiation. 
       FIG. 8  schematically illustrates the structure of an electronic circuit  47  according to a third example. The electronic circuit  47  includes an NPN transistor TR 1  connected to the battery  35 . The LED element of the LED lamp  33  is connected between the positive terminal of the battery  35  and the collector C of the NPN transistor TR 1 . The switch  36  and a first resistor R 1  in series are connected between the positive terminal of the battery  35  and the base B of the NPN transistor TR 1 . A capacitor C 1  and a second resistor R 2  in series are connected to the base B of the NPN transistor TR 1  and the negative terminal of the battery  35 . A third resistor R 3  is connected in parallel with the first resistor R 1 , the capacitor C 1  and the second resistor R 2 . A fourth resistor R 4  is connected between the emitter E of the NPN transistor TR 1  and the negative terminal of the battery  35 . When the switch  36  is closed in the electronic circuit  47 , the second resistor R 2  serves to allow the supply of electric voltage exceeding a predetermined threshold to the base B of the NPN transistor TR 1 . Accordingly, the electric current immediately flows into the collector C of the NPN transistor TR 1 . The time constant circuit R 1 , C 1  serves to gradually increase the electric voltage applied to the base B of the NPN transistor TR 1 . When a predetermined time has elapsed, the applied voltage is maintained constant at the base B of the NPN transistor TR 1 . When the switch  36  is opened, the charge of the capacitor C 1  is released through the third resistor R 3 . 
     The LED lamp  33 , the NPN transistor TR 1 . The capacitor C 1 , and the first to fourth resistors R 1 , R 2 , R 3 , R 4  may be mounted on a common printed circuit board, for example, in the electronic circuit  47 . Wires such as vinyl coated wires or cables may be utilized to electrically connect the first contact  37  of the switch  36 , the first hinge blade  37  or the second hinge blade  28 , the battery  35  and the like to wiring patterns on the printed circuit board. The printed circuit board may be contained within the battery chamber  34 , for example. 
     When the upper box component  13  reaches the opened position, the switch  36  closes in the electronic circuit  47 . The electric voltage is applied to the base B of the NPN transistor TR 1  from the battery  35  in response to the close of the switch  36 . The electric current flows into the base B of the NPN transistor TR 1 , so that the LED lamp  33  starts lighting up. 
     The time constant circuit R 1 , C 1  serves to gradually increase the electric voltage applied to the base B of the NPN transistor TR 1 . The amount of electric current gradually increases through the LED lamp  33 . The LED lamp  33  correspondingly acts to increase the intensity of the ultraviolet radiation to the diamond stone  23 . The color of the diamond stone  23  gradually changes from white (clarity) to blue. A visual performance is in this manner accomplished in response to the opening action of the upper box component  13 . This type of visual performance generates a dramatic impact on one who observes the jewelry box  11 . When the switch  36  is opened, the charge of the capacitor C 1  is released through the third resistor R 3 . 
     Here, the LED lamp  33  is configured to emit radiation other than visible light. Accordingly, the light emitted from the LED lamp  33  is invisible to one who observes the diamond stone  23 . The blue diamond stone  23  predominates in the background, so that the dramatic impact is enhanced. 
     The LED lamp  33  has the directivity Dv allowing the entire radiation to be blocked with the lower box component  12 . One who observes the jewelry box  11  only catches a blue visible light transformed from the ultraviolet light based on the blue fluorescence of the diamond stone  23 , and the ultraviolet light does not leak out of the jewelry box  11 . The eyes of one who observes the jewelry box  11  is prevented from suffering from an influence of the ultraviolet radiation. 
       FIG. 9  schematically illustrates the structure of an electronic circuit  48  according to a fourth example. The electronic circuit  48  includes an NPN transistor TR 1  connected to the battery  35 . The LED element of the LED lamp  33  is connected between the positive terminal of the battery  35  and the collector C of the NPN transistor TR 1 . The switch  36  and a first resistor R 5  in series are connected between the positive terminal of the battery  35  and the base B of the NPN transistor TR 1 . A capacitor C 2  is connected between the base B of the NPN transistor TR 1  and the negative terminal of the battery  35 . A second resistor R 6  is connected in parallel with the first resistor R 5  and the capacitor C 2 . The emitter E of the NPN transistor TR 1  is connected to the negative terminal of the battery  35 . When the switch  36  is closed in the electronic circuit  48 , the time constant circuit R 5 , C 2  serves to gradually increase the electric voltage applied to the base B of the NPN transistor TR 1 . When the voltage reaches a predetermined threshold at the base B of the NPN transistor TR 1 , the electric current flows into the collector C of the NPN transistor TR 1 . When the predetermined time has subsequently elapsed, the applied voltage is maintained constant at the base B of the NPN transistor TR 1 . When the switch  36  is opened, the charge of the capacitor C 2  is released through the second resistor R 6 . 
     The LED lamp  33 , the NPN transistor TR 1 . The capacitor C 2 , and the first and second resistors R 5 , R 6  may be mounted on a common printed circuit board, for example, in the electronic circuit  47 . Wires such as vinyl coated wires or cables may be utilized to electrically connect the first contact  37  of the switch  36 , the first hinge blade  37  or the second hinge blade  28 , the battery  35  and the like to wiring patterns on the printed circuit board. The printed circuit board may be contained within the battery chamber  34 , for example. 
     When the upper box component  13  reaches the opened position so that the switch  36  closes in the electronic circuit  48 , the predetermined voltage is applied to the base B of the NPN transistor TR 1  from the battery  35  after a predetermined time has elapsed subsequent to the close of the switch  36 . This causes the electric current to flow into the collector C of the NPN transistor TR 1 . The LED lamp  33  correspondingly starts to light up. Accordingly, one who observes the jewelry box  11  is allowed to enjoy the diamond stone  23  shining clear and white (transparent) awhile subsequent to the opening of the upper box component  13 . 
     The time constant circuit R 5 , C 2  serves to gradually increase the electric voltage applied to the base B of the NPN transistor TR 1 . The amount of electric current gradually increases through the LED lamp  33 . The LED lamp  33  correspondingly acts to increase the intensity of the ultraviolet radiation to the diamond stone  23 . The color of the diamond stone  23  gradually changes from white (clarity) to blue. A visual performance is in this manner accomplished in response to the opening action of the upper box component  13 . This type of visual performance generates a dramatic impact on one who observes the jewelry box  11 . When the switch  36  is opened, the charge of the capacitor C 2  is released through the second resistor R 6 . 
     It should be noted that the lower box component  12  may be configured to support the LED lamp  33  in place of the upper box component  13 . In this case, the LED lamp  33  may have the directivity Dv allowing the entire radiation to be blocked with the upper box component  13 . In addition, the diamond stone  23  may be mounted on each of mounts constituting a chain of a necklace. The mount may be formed of a metallic material such as platinum, gold or the like. Single piece of diamond stone  23  or pieces of diamond stone  23  may be fixed to the individual mount of the necklace. The diamond stone  23  may be mounted on a pendant, a bracelet, a pierced earring, a ring, an anklet, or the like. A group of diamond stone  23  may include pieces of a constant size or pieces of different sizes. 
     The jewelry box  11  may include, as the switch  36 , a tact switch having a plunger which the upper box component  13  pushes down when the upper box component  13  reaches the opened position. The electronic circuit  38  of the first example and the electronic circuit  43  of the second example may be replaced with any other types of electronic circuit unless such an electronic circuit realizes the identical function. The action of the switch  36  may be interlocked not only with the upper box component  13  assuming the opened position in the aforementioned manner but also with the upper box component assuming the closed position. And the function of the electronic circuit  38 ,  43 ,  47 ,  48  may be realized with the implementation of a software in a microprocessor (MPU).