Abstract:
The present disclosure relates to a LED filament and a LED bulb with the LED filament. The LED filament includes a carrier, LED chips disposed on the carrier, the carrier includes a first lateral section and a second lateral section opposite to the first lateral section, the LED chips are formed on the first lateral section, hardness of the first lateral section is less than that of the second lateral section. The disclosure further provides a LED bulb with the LED filament above. The LED filament above has benefits of improving structural strength and decreasing costs.

Description:
FIELD OF THE DISCLOSURE 
       [0001]    The present disclosure relates to a LED illumination technical field, and more particularly to a LED filament and a LED bulb with the LED filament. 
       BACKGROUND OF THE DISCLOSURE 
       [0002]    A light emitting diode (LED) is a solid-state semiconductor device that can transform electrical energy into visible light. A LED is an ideal light source that can take the place of a conventional light source since it contains benefits such as less energy consumption, longer service life and little environmental contamination, applied in various realms. 
         [0003]    A conventional LED bulb can include a LED filament, a stem, a transparent lampshade such as a spherical lampshade, and a lamp holder such as a thread lamp holder; the transparent lampshade, the stem and the lamp holder are connected firmly, the stem is disposed in the transparent lampshade and equipped with electrodes that can be connected to the LED filament in order to supply power to the LED filament. 
         [0004]    A LED filament includes a copper frame and multiple LED chips disposed on the copper frame. The multiple LED chips can be series connected, parallel connected or series-parallel connected. However, during process of manufacturing a conventional LED bulb, a LED filament mounted on a column can be commonly manual, and an external force is needed in aligning welding, which can easily fail a component caused by the copper frame bend. Moreover, high costs cannot be avoided if power of a single conventional LED filament is increased. 
       SUMMARY OF THE DISCLOSURE 
       [0005]    Therefore, aiming at disadvantages in a conventional technique, the disclosure provides a LED filament and a LED bulb with the LED filament. 
         [0006]    Specifically, an embodiment of the disclosure provides a LED filament, including: a carrier, LED chips disposed on the carrier, the carrier includes a first lateral section and a second lateral section opposite to the first lateral section, the LED chips are formed on the first lateral section, hardness of the first lateral section is less than that of the second lateral section. 
         [0007]    In an embodiment of the disclosure, the carrier includes a substrate, a first adhesive and a second adhesive, the substrate contains a first surface and a second surface opposite to the first surface, the LED chips are disposed on the first surface of the substrate, the first lateral section is formed by the first adhesive covering the first surface and the LED chips, the second lateral section is formed by the second adhesive covering the second surface. 
         [0008]    In an embodiment of the disclosure, Shore hardness type A of the first adhesive is less than or equal to 55, Shore hardness type A of the second adhesive is more than or equal to 70, and a difference of the Shore hardness type A of the first adhesive and the Shore hardness type A of the second adhesive is more than or equal to 15. 
         [0009]    In an embodiment of the disclosure, a material of the first adhesive is transparent resin, such as epoxy resin, silica gel, methyl silicone resin, phenyl silicone resin, methyl phenyl silicone resin or modified silicone resin. 
         [0010]    In an embodiment of the disclosure, a material of the second adhesive is transparent resin, such as epoxy resin, silica gel, methyl silicone resin, phenyl silicone resin, methyl phenyl silicone resin or modified silicone resin. 
         [0011]    In an embodiment of the disclosure, fluorescent powders are dispersed in the first adhesive and the second adhesive. 
         [0012]    In an embodiment of the disclosure, the substrate is formed by a metal material, transparent ceramic, sapphire or glass. 
         [0013]    In an embodiment of the disclosure, through-holes are defined on the substrate. 
         [0014]    In an embodiment of the disclosure, the substrate includes a substrate, a first adhesive and a second adhesive, the substrate includes a first bracket and a second bracket connected with the first bracket, the first bracket contains an upper surface away from the second bracket, the second bracket contains a bottom surface away from the first bracket, the LED chips are disposed on the upper surface of the first bracket, the first adhesive covers the upper surface of the first bracket and the LED chips, the first adhesive and the first bracket form the first lateral section, the second adhesive covers the bottom surface of the second bracket, the second adhesive and the second bracket form the second lateral section. 
         [0015]    In an embodiment of the disclosure, a thermal conductivity of the first bracket is higher than that of the second bracket. 
         [0016]    In an embodiment of the disclosure, brittleness of the first bracket is more than that of the second bracket. 
         [0017]    In an embodiment of the disclosure, a thickness of the first bracket is less than that of the second bracket. 
         [0018]    In an embodiment of the disclosure, the first bracket and the second bracket are formed by metal materials. 
         [0019]    In an embodiment of the disclosure, hardness of a metal material of the first bracket is less than that of the second bracket. 
         [0020]    In an embodiment of the disclosure, the first bracket is formed by copper, the second bracket is formed by iron. 
         [0021]    In an embodiment of the disclosure, the first bracket and the second bracket are connected by pasting with an adhesive. 
         [0022]    In an embodiment of the disclosure, the first bracket and the second bracket are connected by electroplating. 
         [0023]    In an embodiment of the disclosure, through-holes penetrating the first bracket and the second bracket are defined on the substrate. 
         [0024]    In an embodiment of the disclosure, the first bracket is formed by transparent ceramic or sapphire, the second bracket is formed by glass. 
         [0025]    In an embodiment of the disclosure, the first bracket and the second bracket are connected by pasting with an adhesive. 
         [0026]    In an embodiment of the disclosure, the first bracket and the second bracket are connected by pasting with an adhesive, sintering, sputtering or electroplating. 
         [0027]    The disclosure further provides a LED bulb, including: a lamp holder, a transparent lampshade, a stem and a LED filament, the transparent lampshade and the stem are connected with the lamp holder firmly, the LED filament can be any one of the LED filaments in embodiments above. 
         [0028]    In conclusion, according to a LED filament and a LED bulb with the LED filament of the embodiments above, as the hardness of the first lateral section is less than that of the second lateral section, the LED filament above can be designed according to various requirements of structural strength, which can reduce costs without sacrificing structural strength. 
         [0029]    In order to clearly illustrate the disclosure, the following figures will be described in detail, the drawings are merely for explanation instead of limitation. Furthermore, the figures are not sketched in scale, the purpose of the drawings is to illustrate structures and processes of corresponding description literally. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]    Embodiments of the present disclosure are described in detail with reference to the accompanying drawings as follows. 
           [0031]      FIG. 1  is a cross-section diagram of a LED filament according to a first embodiment of the disclosure. 
           [0032]      FIG. 2  is a cross-section diagram of a LED filament according to a second embodiment of the disclosure. 
           [0033]      FIG. 3  is a cross-section diagram of a LED filament according to a third embodiment of the disclosure. 
           [0034]      FIG. 4  is a cross-section diagram of a LED filament according to a fourth embodiment of the disclosure. 
           [0035]      FIG. 5  is a cross-section diagram of a LED filament according to a fifth embodiment of the disclosure. 
           [0036]      FIG. 6  is a cross-section diagram of a LED filament according to a sixth embodiment of the disclosure. 
           [0037]      FIG. 7  is a cross-section diagram of a LED filament according to a seventh embodiment of the disclosure. 
           [0038]      FIG. 8  is a hardness chart in various types. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0039]    Embodiments of the present disclosure are described in detail with reference to the accompanying drawings as follows to better understand the purpose, property and merits of the disclosure. 
       An First Embodiment 
       [0040]    Referring to  FIG. 1 , a LED filament  10  provided by the first embodiment of the disclosure includes: a carrier  12 , multiple LED chips  14  disposed on the carrier  12 . The carrier  12  includes a first lateral section  122  and a second lateral section  124  opposite to the first lateral section  122 . The LED chips  14  are formed on the first lateral section  122 . Hardness of the first lateral section  122  is less than that of the second lateral section  124 . 
         [0041]    As the hardness of the first lateral section  122  is less than that of the second lateral section  124 , the LED filament  10  above can be designed according to various requirements of structural strength, which can reduce costs without sacrificing structural strength of the LED filament  10 . 
         [0042]    In the embodiment, the carrier  12  includes a substrate  121 , a first adhesive  123  and a second adhesive  125 . The substrate  121  contains a first surface  1212  and a second surface  1214  opposite to the first surface  1212 . The LED chips  14  are disposed on the first surface  1212  of the substrate  121 . The first adhesive  123  covers the first surface  1212  and the LED chips  14 , the second adhesive  125  covers the second surface  1214 . The first adhesive  123  forms the first lateral section  122 , the second adhesive  125  forms the second lateral section  124 ; in other words, the first lateral section  122  is formed by the first adhesive  123 , the second lateral section is formed by the second adhesive  125 . 
         [0043]    Specifically, in the embodiment, hardness of the first adhesive  123  and that of the second adhesive  125  are measured by a Shore durometer type A, which means measured hardness is Shore hardness type A. Shore hardness type A of the first adhesive  123  can be less than or equal to 55, Shore hardness type A of the second adhesive  125  can be more than or equal to 70. Preferably, a difference of the Shore hardness type A of the first adhesive and the Shore hardness type A of the second adhesive can be more than or equal to 15. In other embodiments of the disclosure, based on the premise that hardness of the first adhesive  123  is less than that of the second adhesive  125 , hardness of the first adhesive  123  and that of the second adhesive  125  can be measured in another type of hardness, such as shown in  FIG. 8 , hardness of the second adhesive  125  is measured in Shore hardness type D, the Shore hardness D is more than or equal to 20. A material of the first adhesive  123  can be transparent resin, such as epoxy resin, silica gel, methyl silicone resin, phenyl silicone resin, methyl phenyl silicone resin or modified silicone resin. A material of the second adhesive  125  can be transparent resin, such as epoxy resin, silica gel, methyl silicone resin, phenyl silicone resin, methyl phenyl silicone resin or modified silicone resin. In the embodiment, epoxy resin, silica gel, methyl silicone resin, phenyl silicone resin, methyl phenyl silicone resin or modified silicone resin are employed as base materials of the first adhesive  123  and the second adhesive  125 , a difference in hardness of the first adhesive  123  and the second adhesive  125  can be achieved by adjusting ratio of the base material of the first adhesive  123  or that of the second adhesive  125  and fillers and additives. Similarly, time and temperature of heating to solidification of the first adhesive  123  or that of the second adhesive  125  can also be applied to change the hardness without harming other physical features. Otherwise, fluorescent powders can be dispersed in the first adhesive  123  and/or the second adhesive  125 , by which color of light from the LED chips  14  can be adjusted as well. 
         [0044]    The substrate  121  can be formed by a metal material, and through-holes  1216  are defined on the substrate  121 . An effect of the through-holes is to guide lights, which leads to lights from the LED chips  14  can be radiated from the second lateral section  124 . 
         [0045]    The LED chips  14  can be multiple, the LED chips  14  can be series connected, parallel connected or series-parallel connected, each of the LED chips  14  can be connected electrically by metal wires printed on the carrier  12 . 
         [0046]    The carrier  12  of the LED filament  10  above includes the first lateral section  122  and the second lateral section  124  opposite to the first lateral section  122 , the hardness of the first lateral section  122  is less than that of the second lateral section  124 , and the first lateral section  122  is formed by the first adhesive  123 , the second lateral section  124  is formed by the second adhesive  125 ; therefore, the LED filament  10  can obtain high structural strength with low costs. Moreover, as the first lateral section  122  and the second lateral section  124  are formed by the first adhesive  123  and second adhesive  125  separately, the first adhesive  123  can select an adhesive with better heat resistance and heat dissipation, and the second adhesive  125  can select an adhesive with regular heat resistance and heat dissipation; consequently, the LED filament  10  can be guaranteed to dissipate heat rapidly and evenly without increasing costs, which can improve operational power of the LED filament  10 . 
       A Second Embodiment 
       [0047]      FIG. 2  is a LED filament  20  provided by the second embodiment of the disclosure. The LED filament  20  is similar with the LED filament  10 , including a carrier  22 , multiple LED chips  24  disposed on the carrier  22 . The carrier  22  includes a substrate  221 , a first adhesive  223  and a second adhesive  225 . The substrate  221  contains a first surface  2212  and a second surface  2214  opposite to the first surface  2212 . The LED chips  24  are disposed on the first surface  2212  of the substrate  221 . The first adhesive  223  covers the first surface  2212  and the LED chips  24 , the second adhesive  225  covers the second surface  2214 . The first adhesive  223  forms a first lateral section  222 , the second adhesive  225  forms the second lateral section  224 . A difference of the LED filament  20  and the LED filament  10  is: the substrate  221  of the LED filament  20  is formed by a transparent material, such as transparent ceramic, sapphire or glass. And since the substrate  221  is formed by a transparent material, a through-hole is unnecessary to be defined on the substrate  221 . 
       A Third Embodiment 
       [0048]      FIG. 3  is a LED filament  30  provided by the third embodiment of the disclosure. The LED filament  30  is similar with the LED filament  10 , including a carrier  32 , multiple LED chips  34  disposed on the carrier  32 . The carrier  32  includes a first lateral section  322  and a second lateral section  324  opposite to the first lateral section  322 . The LED chips  34  are disposed on the first lateral section  322 . Hardness of the first lateral section  322  is less than that of the second lateral section  324 . 
         [0049]    In the embodiment, the carrier  32  includes a substrate  321 , a first adhesive  323  and a second adhesive  325 . The substrate  321  contains a first bracket  3211  and a second bracket  3213  connected with the first bracket  3211 . The first bracket  3211  contains an upper surface  3212  away from the second bracket  3213 , the second bracket  3213  contains a bottom surface  3214  away from the first bracket  3211 . The LED chips  34  are disposed on the upper surface  3212  of the first bracket  3211 , the first adhesive  323  covers the upper surface  3212  of the first bracket  3211  and the LED chips  34 , the second adhesive  325  covers the bottom surface  3214  of the second bracket  3213 . The first adhesive  323  and the first bracket  3211  form the first lateral section  322 , the second adhesive  325  and the second bracket  3213  form the second lateral section  324 . 
         [0050]    Specifically, a thermal conductivity of the first bracket  3211  can be higher than that of the second bracket  3213 . Brittleness of the first bracket  3211  can be more than that of the second bracket  3213 . A thickness W 1  of the first bracket  3211  can be less than that W 2  of the second bracket  3213 . 
         [0051]    In the embodiment, the first bracket  3211  and the second bracket  3213  are formed by metal materials, with a requirement of hardness of a metal material of the first bracket  3211  is less than that of the second bracket  3213 . For instance, when the first bracket  3211  is formed by copper and the second bracket  3213  is formed by iron, copper can dissipate heat from the LED chips  34  easier because the thermal conductivity is higher, preventing temperature around the LED chips  34  from being excessive; yet iron of the second bracket  3213  can improve the entire structural strength of the LED filament  30  as the property of high strength, and iron materials have high thermal capacity, which can store more heat; hence the LED filament  30  can have higher optional power. 
         [0052]    In the embodiment, the first bracket  3211  and the second bracket  3213  are formed by opaque metal materials, for which through-holes  3216  applied to guide lights can be defined on the substrate  321 . 
         [0053]    Furthermore, in the embodiment, the first bracket  3211  and the second bracket  3213  are connected by pasting with an adhesive  3217 . The adhesive  3217  is preferably a thermal conductive adhesive. 
       A Fourth Embodiment 
       [0054]      FIG. 4  is a LED filament  40  provided by the fourth embodiment of the disclosure. The LED filament  40  is similar with the LED filament  30 , including a carrier  42 , multiple LED chips  44  disposed on the carrier  42 . The carrier  42  includes a substrate  421 , a first adhesive  423  and a second adhesive  425 ; the substrate  421  contains a first bracket  4211  and a second bracket  4213  connected with the first bracket  4211 ; the first bracket  4211  contains an upper surface  4212  away from the second bracket  4213 , the second bracket  4213  contains a bottom surface  4214  away from the first bracket  4211 ; LED chips  44  are disposed on the upper surface  4212  of the first bracket  4211 , the first adhesive  423  covers the upper surface  4212  of the first bracket  4211  and the LED chips  44 , the second adhesive  425  covers the bottom surface  4214  of the second bracket  4213 ; the first adhesive  423  and the first bracket  4211  form a first lateral section  422 , the second adhesive  425  and the second bracket  4213  form a second lateral section  424 . A difference of the LED filament  40  and the LED filament  30  is: the first bracket  4211  of the LED filament  40  is connected to the second bracket  4213  by electroplating. Similarly, in other embodiments, the second bracket  4213  of the LED filament  40  can be connected to the first bracket  4211  by electroplating. 
       A Fifth Embodiment 
       [0055]      FIG. 5  is a LED filament  50  provided by the fifth embodiment of the disclosure. The LED filament  50  is similar with the LED filament  30 , including a carrier  52 , multiple LED chips  54  disposed on the carrier  52 . The carrier  52  includes a substrate  521 , a first adhesive  523  and a second adhesive  525 ; the substrate  521  contains a first bracket  5211  and a second bracket  5213  connected with the first bracket  5211 ; the first bracket  5211  contains an upper surface  5212  away from the second bracket  5213 , the second bracket  5213  contains a bottom surface  5214  away from the first bracket  5211 ; LED chips  54  are disposed on the upper surface  5212  of the first bracket  5211 , the first adhesive  523  covers the upper surface  5212  of the first bracket  5211  and the LED chips  54 , the second adhesive  525  covers the bottom surface  5214  of the second bracket  5213 ; the first adhesive  523  and the first bracket  5211  form a first lateral section  522 , the second adhesive  525  and the second bracket  5213  form a second lateral section  524 . The first bracket  5211  and the second bracket  5213  are connected by pasting with an adhesive  5217 . A difference of the LED filament  50  and the LED filament  30  is: the substrate  521  of the LED filament  50  is formed by a transparent material, such as transparent ceramic, sapphire or glass. Specifically, the first bracket  5211  can be formed by transparent ceramic or sapphire, the second bracket  5213  can be formed by glass. Since the first bracket  5211  and the second bracket  5213  of the substrate  521  are formed by a transparent material separately, a through-hole applied to guide lights is unnecessary to be defined on the substrate  521 . 
       A Sixth Embodiment 
       [0056]      FIG. 6  is a LED filament  60  provided by the sixth embodiment of the disclosure. The LED filament  60  is similar with the LED filament  50 , including a carrier  62 , multiple LED chips  64  disposed on the carrier  62 . The carrier  62  includes a substrate  621 , a first adhesive  623  and a second adhesive  625 ; the substrate  621  contains a first bracket  6211  and a second bracket  6213  connected with the first bracket  6211 ; the first bracket  6211  contains an upper surface  6212  away from the second bracket  6213 , the second bracket  6213  contains a bottom surface  6214  away from the first bracket  6211 ; LED chips  64  are disposed on the upper surface  6212  of the first bracket  6211 , the first adhesive  623  covers the upper surface  6212  of the first bracket  6211  and the LED chips  64 , the second adhesive  625  covers the bottom surface  6214  of the second bracket  6213 ; the first adhesive  623  and the first bracket  6211  form a first lateral section  622 , the second adhesive  625  and the second bracket  6213  form a second lateral section  624 . A difference of the LED filament  60  and the LED filament  50  is: the first bracket  6211  of the LED filament  60  is connected to the second bracket  6213  by sintering, sputtering or electroplating. 
       A Seventh Embodiment 
       [0057]      FIG. 7  is a LED bulb  100  provided by the seventh embodiment of the disclosure, including: a lamp holder  1001 , a transparent lampshade  1003 , a stem  1005  and at least one LED filament  1007 . The lamp holder  1001  is a thread lamp holder; the transparent lampshade  1003  and the stem  1005  are both connected to the lamp holder  1001  firmly; wires can be disposed on the stem  1005  as electrodes of a power source, the electrodes are connected with an outlet by the lamp holder  1001  to supply power for LED chips on the LED filament  1007 . Furthermore, the amount of LED filament  1007  can be one or more, depending on actual requirements. In the embodiment, the LED filament can be any one of the LED filaments in embodiments  1 - 6  above without repeat. 
         [0058]    Overall, according to the LED filaments and the LED bulb with the LED filament of the embodiments of the disclosure, as hardness of the first lateral section is less than that of the second lateral section, the LED filaments above can be designed based on various requirements of structural strength, which can reduce costs without sacrificing structural strength. 
         [0059]    Till now, several embodiments are employed in the disclosure to illustrate principles and executions of the LED filaments and LED bulb of the disclosure, embodiments above are merely for explaining methods and spirits of the disclosure; meanwhile, it is understandable in practical to a person skilled in the art that all or portion of the processes in the method according to the aforesaid embodiment can be accomplished with modifications, equivalent replacements or improvements, in conclusion, the embodiments described above should not be regarded as a limitation, the scope should be covered by the claims.