Patent Publication Number: US-2013229789-A1

Title: Showcase

Description:
TECHNICAL FIELD 
     The present invention relates to a showcase including a main body that has a display space provided with a shelf for displaying commodities, and a transparent plate that is disposed on the front face of the main body and defines the display space, and more specifically, relates to a technique for illuminating commodities displayed on the shelf. 
     BACKGROUND ART 
     Patent document 1 discloses a showcase in which shelves for displaying commodities are provided in a display space of the main body, and an opening of the front face of the main body is covered by a transparent door, and it is possible to open and close the opening, and an illumination module including LED elements is attached to a portion of the main body inside the opening edge. 
     CITATION LIST 
     Patent Document 
     
         
         Patent Document 1: Japanese Laid-open (Kokai) Patent Application Publication No. 2009-112351 
       
    
     SUMMARY OF THE INVENTION 
     Problems to be Solved by the Invention 
     As described above, when LED elements are employed as an illumination module, the illumination module can be reduced in size, so that it is possible to suppress deterioration of visibility due to blockage of displayed commodities by the illumination module and contact of the commodities with the illumination module when the commodities are put in or taken out. 
     However, in a conventional showcase, irradiation direction with illumination light of LED elements is pointed toward a shelf side by a shade and commodities displayed on the shelf are illuminated with direct light. 
     In this configuration, when commodities such as PET bottles are arranged and displayed along the front end of the shelf, commodities close to the illumination module can be brightly illuminated, but the brightness of the commodities decreases farther from the illumination module. Accordingly, there has been a problem in that variation of illuminance of commodities, in other words, the variation in the brightness of the commodities has been remarkable. 
     Furthermore, even in the commodities close to the illumination module, shadowed portions that are not illuminated by direct light from the illumination module are in the dark, and accordingly, there has been a problem that, as a whole, a dark impression is given to customers even if the average illuminance is high. 
     In view of these circumstances, it is an object of the present invention to provide a showcase capable of reducing illuminance variation among commodities arranged on shelves and reducing the shading and shadows between commodities. 
     Means for Solving the Problems 
     In order to achieve the above object, a showcase according to the present invention includes a main body that has a display space provided with a shelf for displaying commodities, and a transparent plate that is disposed on the front face of the main body and defines the display space, and the showcase further includes at least one LED that is disposed on the backside of the transparent plate and illuminates commodities displayed on the shelf with direct light and reflected light from the transparent plate. 
     In such a showcase, since commodities displayed on the shelf are illuminated by direct light from the LEDs and light reflected from the transparent plate, portions of the commodities that are not illuminated by the direct light can be illuminated by reflected light from the transparent plate. 
     Here, the LEDs may be disposed so as to oppose to each other across a space between the transparent plate that defines the front face of the main body and a row of commodities arranged along the front end of the shelf, so that the commodities arranged along the front end of the shelf and the transparent plate are irradiated with light of the LEDs. 
     In such a showcase, it is possible to use the space between the transparent plate that defines the front face of the main body and a row of commodities arranged along the front end of the shelf, to irradiate the commodities arranged along the front end of the shelf with the light of the LEDs, and to illuminate the commodities on the shelf with the reflected light from the transparent plate. 
     Furthermore, a plurality of the LEDs may be disposed in each of end portions opposed to each other on the front face of the main body. In such a showcase, since commodities displayed on the shelf are illuminated form both sides by LEDs disposed so as to oppose each other with direct light from the LEDs and reflected light from the transparent plate, portions of the commodities that are not irradiated with the direct light can be irradiated with the reflected light from the transparent plate. 
     Here, the LEDs may be disposed so that the optical axis center of each LED is set in a direction toward an opposed LED or in a direction slightly inclined toward the shelf side from the direction toward the opposed LED. 
     In such a showcase, light in the vicinity of the optical axis center having high intensity can be radiated toward commodities distant from the LEDs, and light in the vicinity of the optical axis center having high intensity can be radiated toward and reflected from a portion of the transparent plate distant from the LEDs. Accordingly, it is possible to increase the illuminance of the commodities at positions distant from the LEDs. 
     Furthermore, the showcase may include a door that has the transparent plate and that covers the front face of the main body so that the front face can be opened or closed, and the plurality of the LEDs may be disposed in each of left and right end portions on the front face of the main body, that is opened or closed by the door. 
     In such a showcase, the front face of the main body is covered by a door that has the transparent plate so that the front face can be opened or closed, and the commodities can be taken out from the showcase by opening and closing the door. When the door is closed, LEDs illuminate commodities displayed on shelves with direct light and reflected light from the transparent plate. 
     Furthermore, the showcase may include left and right supporting column frames that define an opening of the front face of the main body and have respective grooves, and the LEDs may be disposed in each of the grooves. 
     In such a showcase, it is possible to reduce projection of the LEDs from the supporting column frames, to thereby suppress deterioration of visibility of commodities and contact of the commodities with the LEDs. 
     Furthermore, the showcase may include a rod-shaped illumination module that includes a plurality of arranged and integrated LEDs. The rod-shaped illumination module may be disposed in each of the grooves of the left and right supporting column frames that define the opening of the front face of the main body. 
     In such a showcase, it is possible to dispose a plurality of LEDs in the supporting column frames and to reduce projection of the LEDs from the supporting column frames, to thereby suppress deterioration of visibility of commodities and contact of the commodities with the LEDs. 
     Furthermore, the showcase may include four supporting column frames that constitute the main body and that are the same molded components each having two grooves for fitting therein two plates for defining two faces of the main body in a manner such that the two faces are not opened or closed, and the rod-shaped illumination modules may be disposed in the grooves, that are not used for fitting the plates therein, of the left and right supporting column frames that define the opening of the front face of the main body. 
     In such a showcase, by employing the same molded components for four supporting column frames, it is possible to reduce the number of sorts of molded components constituting the showcase, and by disposing the illumination modules having the LEDs in the groves for fitting the plates therein, it is possible to easily dispose the LEDs in the supporting column frames and to reduce projection of the illumination modules from the supporting column frames. 
     Furthermore, when the door is closed, left and right frames constituting the door may project toward the center side of the opening further than the tip ends of the LEDs so that the LEDs are disposed behind the left and right frames constituting the door. 
     In such a showcase, when the door is closed, the LEDs are concealed behind the left and right frames constituting the door, so that the LEDs are not directly visible from the front face side of the main body. 
     Furthermore, the LEDs may each have a lens for narrowing a light-distribution angle in a plane perpendicular to the arrangement direction. 
     In such a showcase, by narrowing the light-distribution angle by the lens, it is possible to increase the light intensity at the center of light distribution, in other words, at the optical axis center, to thereby increase light irradiation amount at a position distant from the LED. 
     Here, the lens preferably narrows the light-distribution angle in terms of the half maximum range of the light intensity to be about 50 degrees. 
     In such a showcase, by narrowing the light-distribution angle in terms of the half maximum range of the light intensity to be about 50 degrees, the ratio between light irradiation amount on commodities and the transparent plate at positions distant from the LED and light irradiation amount on commodities and the transparent plate at positions close to the LED, becomes proper. 
     Effects of the Invention 
     According to the showcase of the present invention, since illumination with direct light and illumination with reflected light from the transparent plate defining the front face of the main body, are carried out by LEDs disposed on the front face of the main body, it is possible to reduce variation of illuminance on commodities, in other words brightness of the commodities, arranged on the shelf, and to reduce shading and shadows between the commodities. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front view illustrating a showcase of an embodiment of the present invention. 
         FIG. 2  is a cross-sectional view illustrating the showcase of the embodiment of the present invention. 
         FIG. 3  is a partial enlarged cross-sectional view illustrating the showcase of the embodiment of the present invention. 
         FIG. 4  is a perspective view illustrating the showcase of the embodiment of the present invention in a state that a door is open. 
         FIG. 5  is a cross-sectional view illustrating a basic construction of supporting column frames employed in the showcase of the embodiment of the present invention. 
         FIG. 6  is a cross-sectional view illustrating a state in which a post fabrication is applied to the supporting column frames employed in the showcase of the embodiment of the present invention and illumination modules are attached. 
         FIG. 7  is a cross-sectional view illustrating the illumination module to be employed in the showcase of the embodiment of the present invention. 
         FIGS. 8A and 8B  are views illustrating the relationship between the door employed in the showcase of the embodiment of the present invention and the illumination module, in which  FIG. 8A  is a front view illustrating a state in which the door is open and  FIG. 8B  is a front view illustrating a state in which the door is closed. 
         FIG. 9  is a view illustrating direct light and reflected light of the illumination module employed in the showcase of the embodiment of the present invention. 
         FIG. 10  is a view illustrating an ideal light distribution characteristic in the showcase in which illumination of commodities is carried out only with direct light from the illumination module. 
         FIG. 11  is a view illustrating generation of shading in the showcase in which illumination of commodities is carried out only with direct light from the illumination module. 
         FIG. 12  is a view illustrating characteristics of reflected light in the showcase of the embodiment of the present invention. 
         FIG. 13  is a view illustrating characteristics of illumination with direct light and reflected light in the showcase of the embodiment of the present invention. 
     
    
    
     MODE FOR CARRYING OUT THE INVENTION 
     Hereunder embodiments of the present invention will be described in detail with reference to the drawings. 
       FIG. 1  is a front view illustrating a showcase  1  of this embodiment. This showcase  1  illustrated in  FIG. 1  is, for example, an upright type low-temperature showcase for freezing or refrigerating to be installed in a supermarket or a convenience store. 
     Here, a low-temperature showcase is explained in this embodiment, but it may be a temperature-keeping showcase or a temperature-keeping and refrigerating showcase. 
     The showcase  1  includes a housing  3  in which a display space is defined, and a base leg angle  4  attached to the bottom face of the housing  3 . 
     The display space  2  opens to a front face, in other words, a display side, a customer side or a selling space side. The front opening of the display space  2  is covered by a door so that the opening can be opened or closed, and the door has a glass plate  5  being a transparent plate through which the inside is visible. The door  6  is a hinged door that has one side pivotably supported by a side portion of the housing  3 . 
     Both side faces and the back face of the display space  2  are each defined and covered by a glass plate being a transparent plate through which the inside is visible, so that the display space is surrounded by glass plates in four directions. However, in the showcase, at least one of the rear and both sides of the display space may be defined by a heat-insulating panel through which the inside is not visible. 
     Here, the glass plates including the glass plate of the door  6 , by which the display space  2  is defined, are preferably each a double-glazed glass and its glass surface is preferably provided with a transparent heat-insulating film or a heat-insulating coating in order to increase heat-insulating property. 
     Furthermore, in the display space  2 , a plurality of stages of shelves  8  is disposed. In front and rear portions on both sides constituting inner walls of the display space  2 , shelf-supporting columns, not shown, are vertically provided, and the shelf-supporting columns are each provided with a plurality of engaging holes with which the shelves  8  are removably engaged to be disposed. 
     Front and rear faces and side faces of the base leg angle  4  are covered with decorative panels, which define a machine compartment  9  under the display space  2 . 
     In the machine compartment  9 , an evaporator, a cool air-circulating blower, a compressor, a condenser and a blower for the evaporator etc. constituting a cooling apparatus are accommodated, and circulation of cool air by cool air-circulating blower is carried out via a cool air suction port and a cool air discharge port formed on a bottom wall of the display space  2 . 
     Furthermore, in the machine compartment  9 , a mounting platform  11  having four corners provided with casters  10  is accommodated, and on the mounting platform  11 , components such as the compressor constituting the cooling apparatus are mounted. 
       FIG. 2  is a horizontal cross-sectional view of the display space  2  in a state that the door  6  is closed, which shows a front face side portion of the display space  2 . Here, in  FIG. 2 , frames constituting the door are not shown. 
     The housing  3  defining the display space  2  is constituted by four supporting column frames  14 , a door  6  having a glass plate  5 , glass plates  13  defining both side faces and the rear face of the display space  2 , a ceiling plate  17  and a bottom plate (not shown). 
     The supporting column frame  12  is, as illustrated in  FIG. 3 , a resin molded component that integrally has two grooves  14 ,  14  for fitting therein glass plates  13  defining two faces of the display space  2 , and a shelf-supporting column portion  15  for disposing the shelves  8  in the display space  2 . The supporting column frames  12  are configured so that the housing  3  can be constituted by four supporting column frames  12  being the same molded components whose orientations are changed or whose vertical directions are reversed from one another. 
     Here, respective glass plates  13  are fit between left and right supporting column frames  12  on the rear face side, between left and right supporting column frames  12  on the left face side and between left and right supporting column frames  12  on the right face side. However, no glass plate  13  is fit between left and right supporting column frames  12  on the front face side since the front face side is formed into an opening to be opened or closed by the door  6 . 
     In this embodiment, in each of grooves  14  of left and right supporting column frames  12  on the front face side, into which no glass plate  13  is fit, a rod-shaped illumination module  16  is disposed so as to cover the vertical length of the display space  2  as shown in  FIGS. 3 and 4 , and such illumination modules  16  illuminate commodities  7  such as PET bottles disposed on the shelves  8 . 
     As illustrated in  FIG. 5 , four supporting columns at right-front, left-front, right-rear and left-rear positions are constituted by the supporting column frames  12  being the same components whose orientations are changed or whose vertical directions are reversed from one another. In each supporting column frame  12 , two grooves  14 ,  14  for fitting therein two glass plates  13  defining the display space  2 , are formed. Among both opening edges of each groove  14 , an opening edge close to the outside of the display space  2  is provided with a lip-shaped portion formed by folding the portion inside, so that a glass plate  13  can be sandwiched and held by a narrowed portion between the tip of the lip-shaped portion and the other opening edge. 
     As grooves for disposing the illumination modules  16 , grooves  14  of right-front and left-front, into which no glass plate  13  is fit, are employed. 
     Here, the width of the illumination module  16  is narrower than the width of the bottom portion of the groove  14 , but larger than the width of the narrowed portion at which the width is narrowed by the lip-shaped portion. Accordingly, a postfabrication process is applied to the supporting column frame  12  to cut the lip-shaped portion  14   a  in the groove  14  into which no glass plate  13  is fit, and as illustrated in  FIG. 6 , an illumination module  16  is disposed and fixed in the groove  14  of which lip-shaped portion  14   a  is cut and of which open end is thereby widened. 
     The illumination module  16  has, as illustrated in  FIG. 7 , LED lamps, each constituted by an LED (light emitting diode)  16   a  and a lens  16   b , arranged at constant intervals such as intervals of from 10 mm to 15 mm in a longitudinal direction of the illumination module  16  and integrated together. 
     As the LED  16   a , for example, one having a power consumption of about from 0.1 W to 0.5 W and a light-distribution angle of about 120 degrees in terms of the half-maximum range of the light intensity, is employed. 
     Furthermore, the lens  16   b  narrows the light-distribution angle of the LED  16  in a plane perpendicular to the longitudinal direction of the supporting column frame  12  to about 50 degrees, and the narrowing of the light-distribution angle by this lens increases the light intensity in the vicinity of the optical axis center. 
     The narrowing of the light-distribution angle by the lens  16   b  is a value to be appropriately set so that while the closest commodity  7  among commodities  7  arranged along the front end of the shelf  8  is irradiated with direct light, the most distant commodity among commodities  7  arranged along the front end of the shelf  8  is also irradiated with sufficient direct light. Accordingly, the light distribution angle in terms of the half-maximum range of the light intensity is not necessarily 50 degrees. 
     Here, light is emitted substantially symmetrically about the optical axis center when the light is emitted from the lens  16   b.    
     Furthermore, the illumination module  16  has a width W of about 15 mm, a height H of about 13.5 mm and a length determined according to the height of the display space  2 . 
     The height of the illumination module  16  is determined so that the projecting height of the illumination module  16  becomes, for example, 1 mm or less when the illumination module  16  is disposed in the groove  14 , so that the area of the opening of the display space  2  is not narrowed by the illumination module. 
     When the projecting height of the illumination modules  16  from the opening edges of the grooves  14  becomes high, commodities  7  disposed on the left and right ends on the shelf  8  may be partially hidden behind the illumination modules  16  to deteriorate visibility of the commodities  7  or the commodities may contact with the illumination modules  16  when the commodities are put in or taken out. On the other hand, when the illumination module  16  is disposed in the groove  14  so that it does not project significantly from the opening edge of the groove  14 , it is possible to suppress deterioration of visibility of commodities  7  due to the illumination module and to suppress contact of commodities with the illumination module  16  when the commodities are put in and taken out. 
     Furthermore, the optical axis center of the illumination module  16  disposed in the groove  14  is pointed toward an opposing illumination module  16 . 
     That is, two grooves  14  of left and right supporting column frames  12  on the front face side into which no glass plate  13  is fitted, in other words, two grooves  14  located at left and right ends of the opening of the display space  2  in which respective illumination modules  16  are disposed, oppose each other on a plane parallel to the opening of the display space  2  across a space between a glass plate  5  of a door  6 , that is a transparent plate defining a front face of a main body, and commodities arranged along the front end of the shelves  8 . Accordingly, by disposing the illumination modules  16  in the grooves  14  so that their optical axis centers agree with respective opening directions of the grooves  14 , the optical axis centers of the opposing illumination modules  16  point toward each other. 
       FIG. 8A  illustrates the showcase  1  in a state in which the door  6  is open, and  FIG. 8B  illustrates the showcase  1  in a state in which the door  6  is closed. As illustrated in  FIGS. 8A  and B, when the door  6  is closed, left and right frames  6   a ,  6   a  project toward the center side of the display space  2  further than the tip of the illumination module  16 , in more detail, the tips of the LEDs  16   a  including the lenses  16   b , so that the illumination module  16  is disposed behind the left and right frames  6   a ,  6   a  of the door  6 . 
     By this configuration, when the showcase  1  is observed from the front side, the illumination modules  16  are hidden behind the left and right frames  6   a ,  6   a  so that they are not directly visible from the front side. Thus, a customer experiences little glare due to direct light entering into the customer&#39;s field of view from the illumination modules  16 . 
     When the illumination module is turned ON, as illustrated in  FIG. 9 , in a state in which the door  6  is closed, not only on commodities arranged along the front end of each shelf  8  but also a glass plate  5  constituting the door  6  is directly irradiated with light from the illumination module, and the commodities arranged along the front end of each shelf  8  are also irradiated with reflected light from the glass plate  5 . 
     That is, the commodities  7  arranged along the front end of each shelf  8  are illuminated not only by direct light from the illumination module  16  but also by the reflected light from the glass plate  5 . 
     When the commodities  8  arranged along the front end of each shelf  8  are illuminated with only direct light from the illumination module  16 , the direct light does not reach e.g. side faces of the commodities  7  that are on the opposite side from the illumination module  16 , and as a result, clear shading and shadows are formed on the commodities  7 . However, since reflected light from the glass plate  5  is radiated to the commodities  7  at an angle different from that of the direct light from the illumination module  16 , e.g. side faces of the commodities  7  opposite from the illumination module  16  are also irradiated with light and the shading and shadows can be reduced. 
     Furthermore, since the light-distribution angle of the LED  16   a  is narrowed by the lens  16   b , the light intensity in the vicinity of the light-distribution center, in other words in the vicinity of the optical axis center, is increased. Since the light-distribution center is pointed toward distant side commodities  7  among those arranged along the front end of each shelf  8 , the commodities  7  distant from the illumination module  16  can be irradiated with a large amount of direct light. Furthermore, in the light radiated to the glass plate  5  constituting the door  6 , light radiated to a position distant from the illumination module  16  has a large incident angle to the glass plate  5  and thus shows a high reflectance, and accordingly, it is possible to increase the illuminance at the commodities  7  distant from the illumination module  16 . 
     Furthermore, since illumination with direct light and illumination with reflected light are carried out by a pair of illumination modules  16  provided on the left and right sides across the row of the commodities, it is possible to supplement the illuminance at the commodities at positions distant from one illumination module  16  with direct light and reflected light of the other illumination module  16 . Accordingly, it is possible to illuminate the commodities  7  arranged along the front end of each shelf  8  evenly, and it is possible to reduce variation of the illuminance at the commodities  7 , in other words, variation of the brightness of the commodities. 
     As described above, in the showcase  1  of the above embodiment, it is possible to suppress variation of illuminance among the commodities  7  arranged along the front end of each shelf  8 , and to suppress shading and shadows on each commodity  7 , and as a result, the commodities  7  arranged along the front end of each shelf  8  as a whole look bright. 
     When there is a variation of the illuminance among the commodities  7  arranged along the front end of each shelf  8 , or when there are shadings and shadows on each commodity  7 , even if the average illuminance is high, in general, a dark impression is given to the customers. On the other hand, if it is possible to suppress variation of the illuminance among the goods  7  and shading and shadows on each commodity  7 , when the average illuminance is in the same level, it is possible to give a bright impression to customers, and to intensify their desire for purchase. 
     Here, when the door  6  is open, the commodities  7  arranged along the front end of each shelf  7  are not illuminated with reflected light from the glass plate  5  and are only illuminated with direct light from the illumination modules  16 , and as a result, variation of the illuminance among the commodities  7  and shading and shadows on each commodity  7  become large as compared with a case in which the door is closed. 
     However, while the darkness due to the shading and shadows shows up when the door  6  is open, the illumination effect produced by the direct light and the reflected light becomes further impressive when the door is closed. Furthermore, the customer&#39;s desire for purchase is determined when the door is closed, and the customer opens the door after the customer determines the commodity to be purchased. Accordingly, it is sufficient for the commodities as a whole to give a bright impression in a state in which the door  6  is closed. 
       FIG. 10  illustrates required light-distribution characteristics for equalizing illuminances at commodities  7  arranged along the front end of each shelf  8  when the commodities arranged on the shelf are illuminated only with direct light from the illumination modules  16 . 
     That is, logically, to one of the commodities  7  located at the center of the front end of each shelf  8 , substantially equal amounts of light reach from left and right illumination modules  16 , and the illuminance is determined by the sum total of them. To one of the commodities  7  located at a position off the center position, the amount of light from one of the left and right illumination modules is less and amount of light from the other is greater, and it is preferable that the total illuminance be the same as that of the commodity  7  at the center. 
     However, it is difficult to achieve such an ideal light distribution. Furthermore, in the case of illumination only with direct light, it is possible to illuminate uniformly and brightly commodities having no recesses or protrusions such as box-shaped commodities. However, when the arranged commodities  7  are commodities such as PET bottles having recesses or protrusions, as illustrated in  FIG. 11 , a protrusion of one of the commodities  7  close to the illumination module  16  blocks light and produces shading on the commodity  7 . 
       FIG. 12  is a view illustrating characteristics of reflected light in a case in which light from the illumination module  16  is reflected by a glass plate  5  of the door  6  and commodities  7  are illuminated with direct light and reflected light. In order to facilitate understanding, the figure illustrates reflective characteristics of only light from the illumination module  16  disposed on the left side of the front face of the main body. 
     The light reflectance of the glass plate  5  increases as the incident angle to the glass plate  5  increases, and the incident angle increases as the light incident position into the glass plate  5  departs from the illumination module  16 . However, since the light is reflected so that the incident angle equals the reflection angle, light reflected at a position of the glass plate further than the center position is not radiated to the commodities  7  and thus does not contribute to increase of illuminance. 
     However, in the reflection region of the glass plate  5 , from which the reflected light is radiated to the commodities  7 , the reflectivity increases as the distance from the illumination module  16  increases, and the commodities  7  at positions distant from the illumination module  16  can be efficiently illuminated. Furthermore, as illustrated in  FIG. 13 , a shade portion of one of the commodities  7  to which direct light from the illumination module does not reach, can be irradiated with reflected light emitted from the other illumination module  16  and reflected by the glass plate  5 , so as to reduce shading and shadows produced between the commodities  7 . 
     In addition, in the above embodiment, the optical axis center of the illumination module  16  disposed in the groove  14 , is pointed toward an opposing illumination module to each other, but it can be set in a direction slightly inclined toward the shelf  8  side from the direction toward the opposing illumination module  16 , for example, in a direction toward one of the commodities  7  at the most distant position among the commodities  7  arranged along the front end of the shelf  8 . 
     As described above, reflected light of light incident into a distant position of the glass plate  5  in the light emitted from the illumination module  16 , does not reach the commodities disposed on the shelves  8  and thus is wasted. Thus, the optical axis center of the illumination module  16  is inclined toward the shelf  8  side from the direction toward the other opposing illumination module  16  so that the light intensity in a region of the glass plate  5  from which the reflected light is not radiated to the commodities  7  is reduced, and relatively, the light intensity of direct light to the commodities  7  at distant positions is increased to achieve effective illumination. 
     However, in order to incline the optical axis center from the opening direction of the groove  14 , it is necessary to make the pair of left and right illumination modules  16  different components, or to increase projection of each illumination module  16  from the opening edge of the groove  14 . On the other hand, when illumination modules  16  are disposed so that the optical axis of each illumination module  16  points toward the opposing illumination module  16  each other, it is possible to make the pair of left and right illumination modules  16  the same components, and to minimize projection of each illumination module  16  from the opening edge of the groove  14 . 
     Furthermore, it is possible to dispose a pair of illumination modules  16 , that are to be disposed so as to oppose to each other, on the rear side of the frames of the door  6 , which are frames constituting the front face of the main body. In this case, when the door  6  is open, direct light from the illumination modules  16  does not reach the commodities  7  sufficiently, and the illuminance at commodities arranged along the front end of each shelf  8  becomes low. However, as described above, while the darkness due to shading and shadows shows up when the door  6  is open, the illumination effect produced by the direct light and the reflected light becomes further impressive when the door  6  is closed. Furthermore, the customer&#39;s desire for purchase is determined when the door  6  is closed, and in a state in which the customer closes the door, it is possible to perform illumination equivalent to that in the case of disposing the illumination modules  16  in the grooves  14  of the supporting column frames, and accordingly, it is possible to intensify the customer&#39;s desire for purchase. Furthermore, it is possible to suppress decrease of visibility due to blockage by the illumination modules  16  of the commodities  7  and to reduce the risk of contact of the commodities  7  with the illumination module  16  when the commodities  7  are put in or taken out. 
     Furthermore, instead of disposing a pair of illumination modules  16 , which are to be disposed so as to oppose each other, on left and right ends, it is possible to dispose them on upper and lower ends. Furthermore, it is also possible to dispose a pair of illumination modules  16  on left and right ends and another pair of illumination modules on upper and lower ends. Furthermore, it is also possible to dispose an illumination module  16  only on one of the left and the right ends, or only one of the upper and the lower ends. Furthermore, it is also possible to dispose in the central portion of the front face of the main body LEDs for illuminating commodities with direct light and reflected light from the glass plate  5 . 
     Furthermore, in the showcase  1  of this embodiment, the door  6  for opening and closing the display space  2  is provided on the front side of the main body, but it is apparent that illumination modules  16  similar to those of the above embodiment are applicable to a showcase provided with an opening and closing door also on the rear side so as to allow e.g. supplement of commodities through the rear side door. 
     Furthermore, in this embodiment, a showcase having a front face side opened and closed by the door  6  is described. However, also in a showcase having a front face side covered with a glass plate and a rear side provided with an open-close door, it is possible to apply the illumination technique of the present invention, that is a construction in which a plurality of LEDs are arranged along the longitudinal direction of portions of frames constituting a front face of the main body and opposing to each other in a display space, and commodities displayed on shelves are illuminated with direct light from the LEDs and reflected light from the glass plate covering the front face. In such a case, effects similar to those of the above embodiment are obtained. 
     Furthermore, in the above embodiment, all four sides defining the periphery of the display space  2  are constituted by glass plates, but it is possible to constitute at least one side other than the front face by, for example, a non-transparent plate produced by pasting a decorative panel to a heat-insulating material. 
     Furthermore, in the above embodiment, glass plates are employed as transparent plates, but it is also possible to employ transparent resin plates as the transparent plates. Accordingly, the transparent plates are not limited to glass plates. 
     REFERENCE SIGNS LIST 
       1  . . . showcase,  2  . . . display space,  3  . . . housing,  4  . . . base leg angle,  5  . . . glass plate,  6  . . . door,  7  . . . commodity,  8  . . . shelf,  9  . . . machine compartment,  10  . . . caster,  11  . . . mounting platform,  12  . . . supporting column frame,  13  . . . glass plate,  14  . . . groove,  15  . . . shelf-supporting portion,  16  . . . illumination module,  16   a  . . . LED,  16   b  . . . lens,  17  . . . ceiling plate