Abstract:
There is disclosed a showcase provided with a light device capable of simplifying a maintenance operation and improving a cooling efficiency in a display chamber. In a showcase  1  of the present invention, a display chamber  11  is formed in an insulating wall  2  to display commodities in the display chamber  11  while cooling the commodities, the showcase includes LED lights  40  which illuminate the inside of the display chamber  11,  and a light transmitting shade  46  which covers the LED lights  40,  and the shade  46  has a structure to diffuse light from the LED lights  40.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a showcase in which a display chamber is formed in an insulating wall to display commodities in the display chamber while cooling the commodities. More particularly, it relates to lights in the display chamber. 
         [0003]    2. Description of the Related Art 
         [0004]    Heretofore, as this type of showcase, for example, there has been an open showcase  100  disclosed in Patent Document 1 and shown in  FIG. 10 .  FIG. 10  shows a vertical side view of the conventional open showcase  100 . In this open showcase  100 , cold air is discharged from a discharge port  103  formed in an upper edge of an opening  102  of an insulating wall  101  having a substantially U-shaped section toward a suction port  104  of a lower edge of the opening  102 , whereby a cold air curtain is formed in the opening  102 . In consequence, the inside of a display chamber  105  surrounded with the insulating wall  101  is cooled to a predetermined temperature. Then, a plurality of fluorescent lamps  108  are attached to a canopy  107  positioned outside the upper edge of the opening  102 , opposite side edges of the opening  102  and lower surfaces of front parts of shelves  106  to illuminate the inside of the display chamber  105  and the showcase  100  itself. 
         [0005]    [Patent Document 1] Japanese Patent Application Laid-Open No. 5-146346 
         [0006]    However, in the conventional open showcase  100 , the fluorescent lamps  108  are used as light devices, and the fluorescent lamps  108  are provided on an upper front part of the display chamber  105 , the lower surfaces of the shelves  106  disposed in the display chamber  105  and the like, so that there has been a problem that a thermal load is generated in the display chamber  105  owing to the fluorescent lamps  108 . A usual fluorescent lamp converts electric energy into visible radiation, infrared radiation and ultraviolet radiation to radiate a visible ray for use as the light. In this case, a thermal loss is generated, and hence there is a problem that the inside of the display chamber  105  is heated by not only the fluorescent lamps themselves but also radiant heat of the fluorescent lamps. 
         [0007]    Therefore, in a cooling showcase in which the inside of the display chamber  105  is cooled to the predetermined temperature, a cooling operation is performed in consideration of a thermal load due to the light, so that a cooling efficiency lowers. In consequence, there has been a problem that steep rise of running cost is incurred. Commodities displayed in the display chamber  105  are irradiated with an ultraviolet ray, so that there is a problem that the commodities are adversely affected. 
         [0008]    Furthermore, the fluorescent lamps have a problem that flicker is generated owing to use of an alternating current, so that there is a problem that eyes are adversely affected. 
         [0009]    In addition, to attach the fluorescent lamps  108  in the display chamber  105 , components such as sockets and stabilizers are required. Therefore, in attachment positions, attachment places for not only the fluorescent lamps but also the sockets, stabilizers and the like need to be secured. The fluorescent lamps have to be connected to wires in order to supply power to the lamps. There are problems that assembly operability is deteriorated and that increase of the number of the components and steep rise of production cost are incurred. 
         [0010]    In recent years, a thickness of the whole shelves  106  tends to be reduced for a purpose of improving a display efficiency in the display chamber  105 . In actual, there is a problem that a thickness dimension of each shelf  106  is limited by the fluorescent lamp provided under the shelf  106 . 
         [0011]    Moreover, a replacement operation of the fluorescent lamps  108  is forcibly required owing to luminance decrease and light defect caused with elapse of years. Therefore, a user is forced to perform the replacement operation of the fluorescent lamps  108 , and the operation disadvantageously becomes laborious. The new fluorescent lamp  108  for replacement needs to be always prepared, and a storage place of the fluorescent lamp  108  needs to be secured. Furthermore, the fluorescent lamp  108  contains mercury, resulting in a problem that the used fluorescent lamp  108  cannot easily be discarded. 
       SUMMARY OF THE INVENTION 
       [0012]    The present invention has been developed in order to solve a conventional technical problem, and an object thereof is to provide a showcase provided with a light device in which a maintenance operation can be simplified and a cooling efficiency in a display chamber can be improved. 
         [0013]    In a showcase according to the present invention, a display chamber is formed in an insulating wall to display commodities in the display chamber while cooling the commodities, and the showcase is characterized by comprising LED lights which illuminate the inside of the display chamber, and a light transmitting shade which covers the LED lights, the shade having a structure to diffuse light from the LED lights. 
         [0014]    A showcase according to the invention of a second aspect is characterized in that the above invention comprises a reflective plate which extends externally from an opening of the display chamber, the LED lights and the shade are attached to the reflective plate, and the opening of the display chamber is irradiated with the light emitted from the LED lights and passed through the shade. 
         [0015]    A showcase according to the invention of a third aspect is characterized in that in the invention of the first aspect, cold air is discharged from a cold air discharge port provided in an upper edge of a front surface opening of the display chamber, and sucked into a cold air suction port provided in a lower edge of the opening, to form a cold air curtain in the front surface opening of the display chamber, the showcase further comprises a canopy which protrudes forward from an upper front end of the insulating wall; and a reflective plate provided on an inner side of the canopy and positioned before the cold air discharge port, LED lights and a shade are attached to the reflective plate, and the front surface opening of the display chamber is irradiated with light emitted from the LED lights and passed through the shade. 
         [0016]    The showcase according to the invention of a fourth aspect is characterized in that in the above inventions, an outer surface of the shade opposite to the LED lights is formed into a wave-like section or a sawtooth-like section. 
         [0017]    According to the present invention, the showcase in which the display chamber is formed in the insulating wall to display the commodities in the display chamber while cooling the commodities includes the LED lights which illuminate the inside of the display chamber, and the light transmitting shade which covers the LED lights, and the shade has the structure to diffuse the light from the LED lights. Therefore, the shade can diffuse, in multiple directions, the light traveling rectilinearly in parallel from the LED lights to irradiate the inside of the display chamber with the light from the LED lights, and the whole inside of the display chamber can effectively be illuminated also with the light of the LED lights radiated from one direction. 
         [0018]    In consequence, the LED lights can produce a lighting effect similar to that produced in a case where light devices such as a plurality of fluorescent lamps are provided in the display chamber as in a conventional example. Therefore, power consumption of the whole showcase can remarkably be reduced. The LED lights do not radiate any harmful ultraviolet ray or heat ray to the commodities displayed in the display chamber, so that the commodities can be illuminated without being heated, and lowering of a cooling efficiency of the showcase itself due to a thermal load can be prevented in advance. In consequence, running cost of the whole showcase can be reduced. 
         [0019]    According to the invention of the second aspect, in addition to the above invention, the showcase comprises the reflective plate which extends externally from the opening of the display chamber, the LED lights and the shade are attached to the reflective plate, and the opening of the display chamber is irradiated with the light emitted from the LED lights and passed through the shade. Therefore, the LED lights which themselves generate heat can be provided outside the opening of the display chamber. While the lowering of the cooling efficiency in the display chamber is prevented in advance, the opening of the display chamber can effectively be illuminated in a broad region with the light emitted from the LED lights and diffused via the shade. 
         [0020]    In consequence, faces of the commodities displayed so as to be opposed to the opening of the display chamber can be illuminated with the light emitted from the LED lights and diffused via the shade, so that the lighting effect of the commodities can be improved. 
         [0021]    According to the invention of the third aspect, in addition to the invention of the first aspect, the cold air is discharged from the cold air discharge port provided in the upper edge of the front surface opening of the display chamber, and sucked into the cold air suction port provided in the lower edge of the opening, to form the cold air curtain in the front surface opening of the display chamber, the showcase further comprises the canopy which protrudes forward from the upper front end of the insulating wall; and the reflective plate provided on the inner side of the canopy and positioned before the cold air discharge port, the LED lights and the shade are attached to the reflective plate, and the front surface opening of the display chamber is irradiated with the light emitted from the LED lights and passed through the shade. In consequence, the LED lights which themselves generate heat can be provided outside the front surface opening of the display chamber provided with the cold air curtain. While the lowering of the cooling efficiency in the display chamber is prevented in advance, the opening of the display chamber can effectively be illuminated in a broad region with the light emitted from the LED lights and diffused via the shade. 
         [0022]    In consequence, the faces of the commodities displayed so as to be opposed to the opening of the display chamber can be illuminated with the light emitted from the LED lights and diffused via the shade, so that the lighting effect of the commodities can be improved. 
         [0023]    According to the invention of the fourth aspect, in addition to the above inventions, the outer surface of the shade opposite to the LED lights is formed into the wave-like section or the sawtooth-like section. Therefore, the outer surface of the shade formed into the wave-like section or the sawtooth-like section functions as a prism, and can reflect and diffuse the light traveling rectilinearly in parallel from the LED lights in the multiple directions. The broad region can be irradiated with the light emitted from the LED lights by the shade. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]      FIG. 1  is a perspective view of an open showcase to which the present invention is applied; 
           [0025]      FIG. 2  is a vertical side view of the open showcase shown in  FIG. 1 ; 
           [0026]      FIG. 3  is a partially-enlarged sectional view of  FIG. 2 ; 
           [0027]      FIG. 4  is a sectional view of a shade; 
           [0028]      FIG. 5  is a diagram showing an attached state of LED lights; 
           [0029]      FIG. 6  is a diagram showing a result of illuminance measurement; 
           [0030]      FIG. 7  is a vertical side view of a showcase used in the illuminance measurement of  FIG. 6 ; 
           [0031]      FIG. 8  is an enlarged sectional view of a shelf plate front part; 
           [0032]      FIG. 9  is an enlarged sectional view of a handle rail part; and 
           [0033]      FIG. 10  is a vertical side view of a conventional open showcase. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0034]    Next, an embodiment of the present invention will be described in detail with reference to the drawings.  FIG. 1  shows a perspective view of an open showcase  1  to which the present invention is applied, and  FIG. 2  shows a vertical side view of the open showcase  1  shown in  FIG. 1 , respectively. The open showcase  1  is a vertical open showcase to be installed in a store such as a supermarket, and is constituted of an insulating wall  2  opened in a front surface and having a substantially U-shaped section, and insulating side plates  5 ,  5  attached to side surfaces of the insulating wall  2  in an installation spot. 
         [0035]    A partition plate  4  and another partition plate (not shown) are attached on an inner side of the insulating wall  2  of the open showcase  1  so that a space is formed between the wall and each partition plate, and two inner and outer layer ducts are formed between the insulating wall  2  and the partition plate  4  and the like. A bottom plate  9  is attached to a front part of a lower end of a back partition plate  10  constituting the inner partition plate so that a space for the duct is secured between the bottom plate and a bottom wall  2 A of the insulating wall  2 . A display chamber  11  is formed on inner sides of the partition plate  4  and the bottom plate  9 . 
         [0036]    Moreover, in this display chamber  11 , a pair of brackets  31  are attached to a support (not shown) of a back part in the display chamber  11  so that heights and attachment angles of the brackets can be changed, and a plurality of steps of shelf plates  32  each including the brackets to constitute a shelf together are disposed. Price rails  34  molded of a hard synthetic resin are attached to front edges of the shelf plates  32 , and the price rails  34  also serve as decorative members of the shelf plates  32 . A predetermined space is formed between a front wall of each shelf plate  32  and the price rail  34 , and a guard  35  for preventing commodities on the shelf plate  32  from dropping down is attached to the space. 
         [0037]    It is to be noted that in the present embodiment, the shelf plates  32  are constituted of a transparent material having a light transmission property, for example, a glass plate or an acryl plate. The shelf plates  32  constituted of the transparent material have a predetermined strength. In addition, the brackets  31  for attaching the shelf plates  32  to the supports, the price rails  34 , the guards  35  and the like may similarly be constituted of a transparent material. 
         [0038]    An inner layer discharge port  16  and an outer layer discharge port  17  to which honeycomb materials  13 ,  14  are attached, respectively, are arranged in an upper edge of a front surface opening  12  of the insulating wall  2 , and these inner layer discharge port  16  and outer layer discharge port  17  communicate with the inner layer duct and the outer layer duct, respectively. An inner layer suction port  18  and an outer layer suction port  19  are arranged in a lower edge of the opening  12 . 
         [0039]    On the other hand, a plurality of blowers (not shown) for the inner layer duct and the outer layer duct are installed on the bottom wall  2 A of the insulating wall  2  in a rear part under the bottom plate  9 . 
         [0040]    A cooler  39  of a cooling device is vertically provided in the inner layer duct behind the back partition plate  10 . In a case where the blower disposed for the inner layer duct is operated, cold air which has performed heat exchange between the air and the cooler is raised in the inner layer duct, and discharged from the inner layer discharge port  16  toward the inner layer suction port  18 . Then, the cold air sucked from the inner layer suction port  18  is again accelerated by the blower. 
         [0041]    On the other hand, in a case where the blower disposed for the outer layer duct is operated, air in the outer layer duct is raised in the outer layer duct, and discharged from the outer layer discharge port  17  toward the outer layer suction port  19 . Then, the air sucked from the outer layer suction port  19  is again accelerated by the blower. In consequence, double front and rear air curtains are formed in the opening  12 , and the air of a part of the inner cold air curtain is circulated through the display chamber  11  to cool the display chamber  11 . 
         [0042]    On the other hand, a hand rail  20  provided over the whole width of the lower edge of the opening  12  of the open showcase  1  is attached to an upper surface of a lower front wall  2 C of the insulating wall  2 . A front surface lower panel  21  is attached to the front surface of this front wall  2 C so as to continue to the hand rail  20 , and a bumper  22  is attached under the front surface lower panel  21  so that a plane of the bumper is the same as that of the front surface lower panel  21 . 
         [0043]    Next, a constitution of a front part of a ceiling wall  2 B of the insulating wall  2  will be described with reference to  FIGS. 3 to 5 .  FIG. 3  shows a partially enlarged sectional view of  FIG. 2 ,  FIG. 4  is an enlarged sectional view of a shade  46 , and  FIG. 5  is a diagram showing an attached state of LED lights  40 . 
         [0044]    A canopy  33  which protrudes forward is attached to a front end (an upper part front end) of the ceiling wall  2 B of the insulating wall  2 , and a reflective plate  45  is attached to an inner side of the canopy  33  so that the reflective plate protrudes externally from the front surface opening  12  of the display chamber  11 . It is to be noted that a temperature indicator  38  is provided on the front surface of the canopy  33  as shown in  FIG. 1 . 
         [0045]    This reflective plate  45  is constituted of a metal plate decorated with painting, and a front part of the plate is provided with a light attachment portion  41  which is recessed over a longitudinal direction. This light attachment portion  41  opens toward the front surface opening  12  of the display chamber  11  positioned in a rear part under the light attachment portion, and front and rear edges of the light attachment portion  41  are formed to slightly tilt toward the opening in a direction in which the edges come close to each other. 
         [0046]    Then, the surface of this light attachment portion  41  which faces the opening is a light attachment surface  41 A, and the surface is disposed at an angle opposed to the front surface opening  12  of the display chamber  11  from an upper front part, that is, the surface is constituted so as to face the display chamber  11  in an obliquely rear part under the light attachment surface. The LED lights  40  are attached to the light attachment surface  41 A. 
         [0047]    The plurality of LED lights  40  are attached to substrates  42  which extend in the longitudinal direction at predetermined intervals. The substrates  42  provided with the LED lights  40  are fixed via a plurality of fixing screws  43  . . . in a state in which the substrates abut on the light attachment surface  41 A. It is to be noted that the LED lights  40  for use in the present embodiment are of a chip type of white LED light (product number NS6W083T) manufactured by Nichia Corporation. One line or two front and rear lines or more of LED lights  40  may be arranged, and in the present embodiment, two lines of LED lights are provided. In the present embodiment, the front surface opening  12  of the open showcase  1  is formed so as to extend as long as six shaku (about 1830 mm), so that about 108 LED lights  40  are used. 
         [0048]    Moreover, the light attachment surface  41 A of the reflective plate  45  to which the LED lights  40  are attached is provided with a plurality of exhaust holes  44  disposed over the longitudinal direction as shown in  FIG. 5 . 
         [0049]    Then, the light attachment surface  41 A of the light attachment portion  41  is covered with a shade  46  attached so as to surround the LED lights  40 , the substrates  42  and the exhaust holes  44  from the downside. The shade  46  has a shape curved at such a predetermined curvature as to protrude toward the front surface opening  12  of the display chamber  11 . It is to be noted that the shade  46  is fitted into the light attachment portion  41  of the reflective plate  45 , whereby the shade is detachably attached.  FIG. 5  shows a state in which the shade  46  is attached to a part of the light attachment portion  41 . 
         [0050]    This shade  46  is constituted of a colorless transparent material having a light transmission property. In the present embodiment, to diffuse light from the LED lights  40  toward the front surface opening  12  of the display chamber  11 , the surface of the shade which faces the LED lights  40  is formed to be flat and smooth, and an outer surface  46 A of the shade  46  is formed into a wave-like section or a sawtooth-like section as shown in  FIG. 4 . 
         [0051]    In consequence, light traveling rectilinearly in parallel from the LED lights  40  enters the shade  46 , is then refracted in multiple directions by the outer surface  46 A formed into the waveform section or the sawtooth-like section, and can be diffused in a broad region. 
         [0052]    According to such a constitution, when the LED lights  40  are lit, the irradiation light of the LED lights  40  diffused in the shade  46  can effectively illuminate the whole inside of the display chamber  11  from an upper front part positioned outside the display chamber  11 . 
         [0053]    Here, a case where the inside of the display chamber  11  is illuminated with the conventional fluorescent lamps is compared with a case where the inside of the display chamber  11  is illuminated with the LED lights  40  as in the present embodiment with reference to experiment results of  FIG. 6 . In such an experiment, the same showcase except the lights is used for comparison. As experiments using the conventional fluorescent lamps, there are shown two types of experiments including an experiment in which T10 fluorescent lamps (φ32 mm) are used in a canopy, a ceiling board of a chamber and lower surfaces of front parts of four shelves  106  as shown in  FIG. 10  and an experiment in which T5 tube (φ16 mm) fluorescent lamps are used. On the other hand, as an experiment using the LED lights  40  as in the present embodiment, an experiment is shown in which one line of the LED lights  40  are attached to the canopy  33  as shown in  FIG. 7 . 
         [0054]    Then, the four shelves were disposed in the display chamber of each open showcase  1 , and commodities S were mounted on an upper front end of each shelf, followed by measuring illuminance of the light for irradiating the face of each commodity was irradiated. It is to be noted that the face of the commodity S on the top shelf is point A, the face of the commodity S on the second shelf is point B, the face of the commodity S on the third shelf is point C, and the face of the commodity S on the fourth shelf is point D. 
         [0055]    According to this measurement, with regard to the illuminance of each point in a case where the T10 fluorescent lamps were used, the illuminance of the point A was 1260 LX, that of the point B was 830 LX, that of the point C was 600 LX, and that of the point D was 600 LX. With regard to the illuminance of each point in a case where the T5 tube fluorescent lamps were used, the illuminance of the point A was 1800 LX, that of the point B was 1300 LX, that of the point C was 700 LX, and that of the point D was 470 LX. It is seen that in the positions other than the point D, the illuminance of the T5 tube fluorescent lamp is high as compared with a case where the T10 fluorescent lamp is used. 
         [0056]    On the other hand, in a case where the LED lights  40  were attached to the reflective plate  45  on the inner side of the canopy  33  as in the present embodiment, the illuminance of the point A was 2380 LX, that of the point B was 1520 LX, that of the point C was 1000 LX, and that of the point D was 812 LX. Therefore, it is seen that in any point, the illuminance of the light for irradiating the commodities mounted on the shelves is high in a case where the LED lights  40  are used as compared with a case where the fluorescent lamps are used as in the conventional example. 
         [0057]    Moreover, when the total demands of lighting in the above-mentioned cases are compared, the total demand of lighting is 468 W in the case where the T10 fluorescent lamps are used, it is 356 W in the case where the T5 tube fluorescent lamps are used, and it is 198 W in the case where the LED lights  40  are used. Assuming that the demand of the case where the T10 fluorescent lamps are used is 100, the demand of the T5 tube fluorescent lamps is 76%, and the demand of the LED lights  40  is 42%. 
         [0058]    Therefore, in a case where the LED lights  40  are used in illuminating the display chamber  11  as in the present embodiment, an equal or more lighting effect can be produced as compared with a case where light devices such as the plurality of fluorescent lamps are provided in the display chamber as in the conventional example. Therefore, even in a constitution in which the shelf plates  32  are not provided with self-emitting light fixtures, for example, a constitution in which light fixtures such as the fluorescent lamps are not provided on lower surfaces of the shelf plates  32  or the like, commodities to be displayed on the shelf plates  32 , especially milk packages, plastic bottled beverages and the like are mounted in uprising states, and faces of the commodities which face the front surface opening  12  of the display chamber  11  can effectively be illuminated. 
         [0059]    This obviates the need for the light fixtures on the shelf plates  32 , whereby power leakage due to dew condensation can be prevented. This can also obviate the need for components to be attached to the lights, for example, sockets for attaching these light fixtures, stabilizers and the like. A constitution of the shelves can be simplified. Moreover, the number of the components can be reduced, so that productivity can be improved. 
         [0060]    Moreover, the LED lights  40  attached to the reflective plate  45  of the canopy  33  can produce the lighting effect similar to that produced in the case where light devices such as the plurality of fluorescent lamps are provided in the display chamber as in the conventional example, so that power consumption of the whole open showcase  1  can remarkably be reduced. 
         [0061]    Furthermore, the LED lights  40  do not radiate any harmful ultraviolet ray or heat ray to the commodities displayed in the display chamber  11 , so that the commodities can be illuminated without being heated. In particular, the LED lights  40  which generate heat are provided on the inner side of the canopy  33  which protrudes forward from the upper front end of the insulating wall  2 , so that the inside of the display chamber  11  is illuminated from the outside of the display chamber  11 , that is, from the outside of the cold air curtain. Therefore, a thermal load concerning the lighting in the display chamber  11  can be zeroed, and lowering of the cooling efficiency of the showcase  1  itself can be prevented in advance. In consequence, running cost of the whole showcase  1  can be reduced. 
         [0062]    Moreover, it is possible to avoid a disadvantage that the commodities are adversely affected by the harmful ultraviolet ray of the lights. In consequence, the commodities can be displayed while fresher states thereof are maintained. 
         [0063]    On the other hand, the substrates  42  provided with the LED lights  40  are attached so as to abut on the reflective plate  45  constituted of a metal plate so that heat exchange between the substrates and the reflective plate can be performed. Therefore, exhaust heat generated from the substrates  42  of the LED lights  40  is transmitted to the reflective plate  45 , whereby a heat release effect of the reflective plate  45  can be obtained. In consequence, the heat generated from the substrates  42  of the LED lights  40  can smoothly be released. 
         [0064]    Furthermore, in the LED lights  40 , unlike the heretofore used fluorescent lamps, any flicker is not generated, so that stable lights can be obtained, and the commodities can appropriately be illuminated. In addition, the LED lights  40  can easily be dimmed. Therefore, the dimming is performed in accordance with the commodities to be displayed in the display chamber  11 , whereby further effective lighting can be performed. 
         [0065]    Moreover, the LED lights  40  has a remarkably long life period as compared with the fluorescent lamp, and this can obviate the need for a replacement operation of the lights. Therefore, this can obviate the need for a laborious operation such as storage of replacement components or a treatment of wastes discharged owing to the replacement. 
         [0066]    Furthermore, in the present embodiment, the light traveling rectilinearly in parallel from the LED lights  40  can be diffused in the multiple directions by the shade  46  which covers the LED lights  40  and which has a light transmission property, so that the front surface opening  12  of the display chamber  11  can be irradiated with the light from the LED lights  40  in a broad region. The whole inside of the display chamber  11  can effectively be illuminated even with the LED lights  40  from one direction. 
         [0067]    In consequence, the commodities displayed so as to be opposed to the front surface opening  12  of the display chamber  11 , especially the milk packages, the plastic bottled beverages and the like are mounted in the upright states, and the faces of the commodities which face the front surface opening  12  of the display chamber  11  can be illuminated with the light emitted from the LED lights  40  diffused via the shade  46 . Therefore, the lighting effect of the commodities can be improved. 
         [0068]    Moreover, in the present embodiment, the outer surface  46 A of the shade  46  on a side opposite to the LED lights  40  is formed into the wave-like section or the sawtooth-like section. Therefore, the outer surface of the shade  46  formed into the wave-like section or the sawtooth-like section functions as a prism, and can refract, reflect and diffuse the light traveling rectilinearly in parallel from the LED lights in the multiple directions. The broad region can be irradiated with the light emitted from the LED lights by the shade. 
         [0069]    Therefore, as described above, the light from the LED lights  40  can produce a lighting effect equal to or more than that produced in the case where light devices such as the plurality of fluorescent lamps are provided in the display chamber as in the conventional example. 
         [0070]    Moreover, in the present embodiment, the shelf plates  32  and the like of the shelves disposed in the display chamber  11  are constituted of the transparent material as described above. Therefore, the shelves constituted of the transparent material are irradiated from above with the light emitted from the LED lights  40 , and then the light passes through the shelves, whereby the light emitted from the LED lights  40  can travel through the whole display chamber  11  without being disturbed by the shelves, and the lighting effect of the whole display chamber  11  can be improved. 
         [0071]    Therefore, according to such a constitution, the commodities on the shelves can be illuminated without providing any special light fixture on the shelf plates  32 . This can obviate the need for the components to be attached to the lights, for example, the sockets for attaching these light fixtures and the like, and the constitution of the shelves can be simplified. 
         [0072]    Moreover, in addition to the shelf plates  32  and the like constituted of the transparent material, as shown in  FIG. 8 , the shelf plate  32  may be constituted of a heretofore used steel plate material, and a light guide plate  48  may be attached to a lower surface of the shelf plate  32 . This light guide plate  48  is constituted of, for example, an acryl resin or the like, and attached to the whole lower surface of the shelf plate  32  in a state in which the light guide plate slightly protrudes forward (toward the LED lights  40 ) from a front end of the shelf plate  32  (the whole shelf including the price rail  34  and the like). The front end of the light guide plate  48  disposed so as to protrude forward from the shelf plate  32  is provided with a light inlet portion  49 . The ray inlet portion  49  is configured to receive the light from the LED lights  40  and reflect the light rearward. 
         [0073]    On the other hand, the surface of the light guide plate  48  which faces the lower surface of the shelf plate  32  is provided with a plurality of grooves, scratches and the like for irregularly reflecting the derived light, and a reflective sheet  50  is attached to the corresponding surface. Then, a diffusion sheet  51  is attached to the surface of the light guide plate  48  opposite to the lower surface of the shelf plate  32 , that is, a light emitting surface  52 . 
         [0074]    According to such a constitution, the inside of the display chamber  11  is illuminated from above with the LED lights  40 , whereby the light emitted from the LED lights  40  is struck on the light inlet portion  49  of the light guide plate  48  provided so as to protrude forward from each shelf plate  32 . In consequence, the light derived rearward from the light inlet portion  49  is irregularly reflected by the scratches formed on the surface of the light inlet portion on the side of the lower surface of the shelf plate  32 , and the reflective sheet  50 , and the light is then diffused by the diffusion sheet  51  on the facing light emitting surface  52 , and emitted. Therefore, the irradiation light from the LED lights  40  is emitted from the light emitting surface  52  of the light guide plate  48  provided on the whole lower surface of the shelf plate  32  via the light guide plate  48 . 
         [0075]    Therefore, the diffused light is radiated from the light emitting surface  52  of the light guide plate  48 , whereby the whole upper surface of the shelf plate  32  positioned under the shelf plate  32  provided with the light guide plate  48  so as to face the shelf plate is illuminated. Therefore, the inside of the display chamber  11  can be illuminated from above only with the LED lights  40  which illuminate the inside of the display chamber  11  from above. Moreover, not only the faces of the commodities mounted on the shelf plates  32  but also the commodities mounted on rear parts of the shelf plates  32  can be illuminated. In consequence, the whole inside of the display chamber  11  can effectively be illuminated. 
         [0076]    In particular, to illuminate the shelf plate  32  provided with the light guide plate  48  disposed above the shelf plate, the light emitted from the LED lights  40  and struck on the light inlet portion  49  of the light guide plate  48  is emitted from the light emitting surface  52  of the light guide plate  48  disposed so as to face the shelf plate  32 . Therefore, the light fixtures do not have to be especially disposed. This obviates the need for the sockets, wires and the like, and hence the constitution of the shelves can be simplified. 
         [0077]    It is to be noted that in the present embodiment, the light guide plate  48  is provided over the whole lower surface of the shelf plate  32 , but the present invention is not limited to such a constitution as long as the light guide plate is formed so as to extend along a depth dimension from a front side of the shelf plate  32 . 
         [0078]    Moreover, in addition to the constitution of the LED lights  40  provided on the inner side of the canopy  33  or instead of the constitution of the LED lights  40 , it may be constituted that the inside of the display chamber  11  may be illuminated with the LED lights  40  from a lower front part of the display chamber  11 . 
         [0079]    In such a case, as shown in  FIG. 9 , the hand rail  20  of the above embodiment is constituted of a hand rail main body  24  provided over the whole width of the lower edge of the front surface opening  12  of the open showcase  1 , a reflective plate  26  provided on an upper surface of the hand rail main body  24  so as to extend over the whole width of the lower edge of the opening  12 , and a front surface upper panel  25  which covers the front surface of the hand rail main body  24  from an upper end of the body, and the LED lights  40  are attached to the reflective plate  26 . 
         [0080]    The reflective plate  26  is constituted of a metal plate, and arranged so as to perform heat exchange between the reflective plate and the hand rail main body  24  or the front surface upper panel  25  similarly constituted of the metal plate. It is to be noted that, for example, an aluminum material having a high heat exchange efficiency is used in the metal plate for use in the reflective plate  26 . Then, an upper surface of the reflective plate  26  is provided with a light attachment portion  26 A which is recessed over the longitudinal direction, in the same manner as in the reflective plate  45 . Front and rear edges of this light attachment portion  26 A are provided with engagement claws  26 B for detachably attaching a shade  53 . 
         [0081]    Then, the surface of this light attachment portion  26 A which faces the opening is a light attachment surface  26 C, and the surface is disposed at an angle opposed to the front surface opening  12  of the display chamber  11  from a lower front part, that is, the surface is constituted so as to face the display chamber  11  in an obliquely rear part above the light attachment surface. The LED lights  40  having a constitution similar to that of the LED lights attached on the inner side of the canopy  33  are attached to the light attachment surface  26 C. 
         [0082]    Then, the light attachment surface  26 C of the light attachment portion  26 A is covered with a shade  53  attached so as to surround the LED lights  40  and the like from the upside. The shade  53  has a shape curved at such a predetermined curvature as to protrude toward the front surface opening  12  of the display chamber  11 . It is to be noted that front and rear ends of the shade  53  are fitted into the engagement claws  26 B of the light attachment portion  26 A of the reflective plate  26 , whereby the shade is detachably attached. It is to be noted that a constitution of the shade  53  is substantially the same as that of the shade  46 , and hence detailed description thereof is omitted. 
         [0083]    According to such a constitution, when the LED lights  40  are lit, the irradiation light of the LED lights  40  diffused by the shade  53  can effectively illuminate the whole inside of the display chamber  11  from a lower front position outside the display chamber  11 . 
         [0084]    Therefore, even in such a constitution, even when light fixtures such as the fluorescent lamps are not provided on the lower surfaces of the shelf plates  32  provided in the display chamber  11  and the like, the faces of the commodities displayed on the shelves can effectively be illuminated in the same manner as in the case where the LED lights  40  are attached to the inner side of the canopy  33  as described above. Therefore, this obviates the need for the light fixtures on the shelves, whereby the power leakage due to the dew condensation can be prevented. This can also obviate the need for the components to be attached to the lights, for example, the sockets for attaching these light fixtures, the stabilizers and the like, and the constitution of the shelves can be simplified. 
         [0085]    Moreover, the LED lights  40  attached to the reflective plate  26  can produce a lighting effect similar to that produced in the case where light devices such as the plurality of fluorescent lamps are provided in the display chamber  11  as in the conventional example, so that the power consumption of the whole showcase can remarkably be reduced. 
         [0086]    Furthermore, even in this case, the LED lights  40  are provided outside the cold air curtain, whereby the thermal load concerning the lighting in the display chamber  11  can be zeroed, and the lowering of the cooling efficiency of the showcase  1  itself can be prevented in advance. In consequence, the running cost of the whole showcase  1  can be reduced. 
         [0087]    In addition, heat generated from the substrates  42  of the LED lights  40  is released in the reflective plate  26  attached to the hand rail main body  24  provided in the vicinity of a cold air suction port such as the outer layer suction port  19 , whereby the vicinity of the cold air suction port in which the dew condensation is easily generated can be heated. It is possible to suppress the generation of the dew condensation on the reflective plate  26 , the hand rail main body  24  and the front surface upper panel  25  constituting the hand rail  20 . 
         [0088]    In consequence, the dew condensation can be prevented using the heat released from the LED lights  40 , and a heater for preventing the dew condensation does not have to be especially provided on the hand rail  20 . 
         [0089]    It is to be noted that in the above embodiment, the hand rail  20  is constituted of the hand rail main body  24 , the reflective plate  26  and the front surface upper panel  25 , but the present invention is not limited to such a constitution. Even in a constitution in which the hand rail  20  is constituted of one component, the hand rail  20  is formed of a metal member, a reflective portion is provided at a position opposed to the front surface opening  12  of the display chamber  11  from a lower front part and the LED lights  40  are attached to the reflective portion, a similar effect is produced. 
         [0090]    Moreover, in the above embodiment, the LED lights  40  are attached to the inner side of the canopy  33  and the hand rail  20  to illuminate the inside of the display chamber  11  from the upper front part or the lower front part, but the present invention is not limited to this embodiment. The LED lights  40  may be attached to, for example, the side plates  5  and the like to illuminate the inside of the display chamber  11  from side parts as long as the LED lights  40  are arranged outside the display chamber  11 . In consequence, the thermal load concerning the lighting in the display chamber  11  can be zeroed, and the lowering of the cooling efficiency of the open showcase  1  itself can be prevented in advance. 
         [0091]    In addition, the LED lights  40  similar to those of the above embodiment may be attached to a ceiling partition plate  8  disposed on a display chamber  11  side of the inner layer discharge port  16 , the side plates  5  and the like to illuminate the inside of the display chamber  11  from the upside and the opposite sides. In consequence, the inside of the display chamber  11  can effectively be illuminated. 
         [0092]    In the above-mentioned cases, the substrates  42  of the LED lights  40  are attached to portions where the dew condensation is easily generated as in the hand rail  20 , or attached so as to perform heat exchange between the substrates and the portions where the dew condensation is easily generated, whereby the dew condensation can be prevented using the heat released from the LED lights  40 , and the heater for preventing the dew condensation does not have to be especially provided. 
         [0093]    Moreover, in the present embodiment, an example in which the LED lights  40  are attached to a so-called vertical type open showcase has been described, but the present invention is not limited to this embodiment. A similar effect can be produced even with respect to a horizontal type open showcase.