Abstract:
Various embodiments may relate to a lamp holder of a lighting module, including a first housing and a second housing made from different materials, wherein the second housing includes a body part and an assembling part in thermal contact with each other, wherein the second housing is embedded integrally in the first housing and in thermal contact with the first housing, and the assembling part and the body part are installed together. In addition, various embodiments further relate to a method for manufacturing the lamp holder and an illuminating device having the lamp holder.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a lamp holder and a method for manufacturing the lamp holder and an illuminating device comprising the lamp holder. 
       BACKGROUND ART 
       [0002]    In the manufacturing process of modern electronic device, especially LED illuminating device, the injection molding, especially the overmolding process, is used more and more for manufacturing the lamp holder of the illuminating device. By manufacturing through such processes, the lamp holder not only can realize good heat exchange, but also can guarantee good insulation property of the illuminating device. In the prior art, a hybrid illuminating device made from metal and plastic is usually used as the lamp holder of the illuminating device. Such lamp holder has a first housing of metal and a second housing of plastic wrapping the outside of the first housing. Thus, with the aid of the thermal conduct property of metal, heat inside the illuminating device can be highly effectively and quickly transferred to the second housing so as to achieve good heat dissipation effect. Moreover, since the electrically insulating second housing wraps the outside of the first housing of metal, the first housing can be electrically insulating from the outside. 
         [0003]    For this hybrid heat dissipation device configured as a lamp holder, the first housing made from a metal material, for instance, usually should be made integrally through a process similar to die casting; therefore, a high defective rate is always resulted from the manufacturing process. Moreover, due to requirements of the die casting process to the equipment and manufacturing time, etc., the manufacturing cost thereof also cannot be ignored. 
       SUMMARY OF THE INVENTION 
       [0004]    Therefore, one object of the present invention lies in providing a lamp holder of a lighting module. Such lamp holder is easily manufactured and has a low cost, and therefore can reduce the defective rate resulted from the manufacturing process. 
         [0005]    The lamp holder of a lighting module provided according to the present invention comprises a first housing and a second housing made from different materials, characterized in that the second housing comprises a body part and an assembling part in thermal contact with each other, wherein the second housing is embedded integrally in the first housing and in thermal contact with the first housing, and the assembling part and the body part are installed together. By designing the second housing in a two-part structure, the body part and the assembling part can be manufactured individually through various processes, respectively, moreover, by means of the thermal contact between the first housing and the second housing, the thermal conductivity of the lamp holder can be ensured to meet requirements in application circumstances. Therefore, various problems such as too high cost and high defective rate brought by, for instance, the die casting process in the conventional manufacturing process can be advantageously avoided. 
         [0006]    According to a preferred solution of the present invention, the body part is made from a metal through a first process, and the assembling part is made from a metal through a second process. By manufacturing the body part and the assembling part through different processes, appropriate processes can be chosen according to the specific structures of the two parts, thereby improving the yield in the manufacture. 
         [0007]    According to a preferred solution of the present invention, the body part is configured as a metal stamping part, and the assembling part is configured as a metal extrusion part. To manufacture the assembling part through the extrusion process can apparently save the cost relative to the die casting process. 
         [0008]    According to a preferred solution of the present invention, the body part and the assembling part are installed together in a manner of interference fit. Consequently, assembling of the second housing is realized without additional fastener or connector. 
         [0009]    According to a preferred solution of the present invention, the body part and the assembling part are nested together. Stresses pressing each other are present between the body part and the assembling part nested therein. 
         [0010]    According to a preferred solution of the present invention, an outer circumferential wall of the assembling part is against an inner circumferential wall of the body part. 
         [0011]    According to a preferred solution of the present invention, an end region of the body part facing to a light emergent side of the lighting module surrounds the assembling part. 
         [0012]    According to a preferred solution of the present invention, the body part is configured as a cup, wherein the assembling part is embedded in an end region of the body part having a bigger cross section, and an end region of the body part having a smaller cross section is embedded in the first housing. That is to say, the major-diameter end of the body part is configured for fixed connection with the assembling part, and the remaining parts, especially the minor-diameter end, can be completely embedded in the first housing. 
         [0013]    According to a preferred solution of the present invention, the body part and the assembling part are made from a rigid material. Therefore, interference fit between the body part and the assembling part can be ensured, moreover, the second housing formed thereby has a fixed profile. 
         [0014]    According to a preferred solution of the present invention, the body part and the assembling part are made from aluminum. Aluminum has the advantages of low density and good thermal conduct effect and therefore is fit for manufacturing the second housing. Of course, other suitable metal materials also can be taken into consideration for manufacturing, or different metal materials also can be taken into consideration for manufacturing separately, the body part and the assembling part. 
         [0015]    According to a preferred solution of the present invention, the body part and the assembling part are installed together in a manner of thermal expansion and contraction. For instance, the body part can be heated to slightly increase the major-diameter end thereof, thereby the assembling part can be successfully embedded therein, and then it is quickly cooled to ensure formation of interference fit between the body part and the assembling part. 
         [0016]    According to another preferred solution of the present invention, the body part and the assembling part are installed together in a manner of stamping. 
         [0017]    According to a preferred solution of the present invention, the first housing is a cup, and an inner circumferential wall of the first housing defines an accommodation cavity for placing the lighting module. 
         [0018]    According to a preferred solution of the present invention, the assembling part is configured as a ring part, wherein the inner circumferential wall of the assembling part can be configured for connection or contact with parts which need to be fixed in the lamp holder. 
         [0019]    According to a preferred solution of the present invention, a stop portion for the assembling part is in an end region of the first housing facing to a light emergent side of the lighting module. Thereby, an anti-stripping structure is formed in an axial direction, preventing the second housing from escaping from the first housing. 
         [0020]    According to a preferred solution of the present invention, the stop portion extends radially inwardly, and the assembling part is sandwiched axially between the stop portion and an end surface of an inner circumferential wall of the first housing. 
         [0021]    According to a preferred solution of the present invention, at least one groove is formed on an inner wall of the assembling part. The groove can be configured as accommodation groove for receiving fasteners such as screws or the like, as a result, the lamp holder, especially the assembling part, can be ensured to be in fixed connection with parts which need to be fixed in the lamp holder. 
         [0022]    According to a preferred solution of the present invention, a plurality of grooves are formed on the inner wall of the assembling part, and the plurality of grooves are distributed uniformly in a circumferential direction. Therefore, it can be ensured that the lamp holder can be in uniform and circumferentially full fixed connection with parts which need to be fixed in the lamp holder. 
         [0023]    According to a preferred solution of the present invention, the first housing is made from a plastic. Advantageously, the first housing and the second housing are formed in one piece through an overmolding process. 
         [0024]    According to a preferred solution of the present invention, the lamp holder is a heat sink. The lamp holder can support, protect and radiate heat for the lighting module accommodated therein. 
         [0025]    In addition, the present invention further relates to a method for manufacturing the above lamp holder, characterized by comprising steps of: 
         [0000]    a) providing the body part and the assembling part for forming the second housing;
 
b) fixing together, by interference fit, the body part and the assembling part which are in thermal contact with each other so as to form the second housing; and
 
c) moulding an insulating first housing on the second housing, wherein the second housing is at least partly embedded in the first housing and is in thermal contact with the first housing so as to form the lamp holder.
 
         [0026]    By manufacturing in two parts the second housing in this hybrid lamp holder, the manufacturing cost of the second housing, or the whole lamp holder, can be reduced, and the yield in the manufacture of the lamp holder is improved. 
         [0027]    According to a preferred solution of the present invention, in step a) the assembling part is made through an extrusion process, and the body part is made through a stamping process. 
         [0028]    According to a preferred solution of the present invention, in step b) the body part and the assembling part are nested together. 
         [0029]    According to a preferred solution of the present invention, in step c) the first housing is made from a plastic, wherein an overmolding process is used to enable the first housing to wrap the second housing in one piece. 
         [0030]    The present invention further relates to an illuminating device, comprising a lighting module, characterized by further comprising the above lamp holder. 
         [0031]    It shall be understood that both the above general description and the following detailed description are for illustrative and explanative purposes in order to provide further description of the claimed present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0032]    The accompanying drawings constitute a part of the present Description and are used to provide further understanding of the present invention. Such accompanying drawings illustrate the embodiments of the present invention and are used to describe the principles of the present invention together with the Description. In the accompanying drawings the same components are represented by the same reference numbers. As shown in the drawings: 
           [0033]      FIG. 1  shows a 3D sectional view of a first embodiment of a lamp holder according to the present invention; 
           [0034]      FIG. 2  shows a 3D exploded view of a second housing of the lamp holder as shown in  FIG. 1 ; 
           [0035]      FIG. 3  shows a 3D view of the second housing as shown in  FIG. 1  after assembling; and 
           [0036]      FIG. 4  shows a 3D exploded view of an illuminating device according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0037]    In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which are shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as “top”, “bottom”, “inner”, “outer”, is used in reference to the orientation of the figures being described. Because components of embodiments of the present invention can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims. 
         [0038]    It is to be understood that the features of the various exemplary embodiments described herein may be combined with each other, unless specifically noted otherwise. 
         [0039]      FIG. 1  shows a 3D sectional view of a first embodiment of a lamp holder according to the present invention. A lamp holder  100  comprises a first housing  1  and a second housing  2 , wherein the first housing  1  is an insulating housing made from a plastic, and the second housing  2  is a metal housing made from a metal. Therefore, the overmolding process can be preferably used to enable the first housing  1  to wrap and to be formed integrally with the second housing  2 . In cases where the first housing  1  is made from a thermal conductive plastic, the lamp holder  100  can dissipate heat for a lighting module installed therein, and therefore can be a heat sink. 
         [0040]    According to the present invention, the second housing  2  comprises a body part  21  and an assembling part  22  in thermal contact with each other, wherein the assembling part  22  and the body part  21  are installed together such that the second housing  2  can be integrally embedded in the first housing  1 . 
         [0041]    In this situation, the thermal contact between the second housing  2  and the first housing  1  can be realized. In an end region of the first housing  1  facing to a light emergent side of the lighting module (not shown), i.e. in the upper part of the figure, there is a stop portion  11  for the assembling part  22 . The stop portion  11  extends radially inwardly starting from an inner wall of the first housing  1  so as to form a ring structure. The assembling part  22  is sandwiched axially between the stop portion  11  and an end surface of an inner circumferential wall A 1 . Thus, it can be ensured that the assembling part  22  is located in a fixed position in the first housing  1  so as to prevent the second housing  2 , when influenced by an external force, from stripping from the first housing  1 . 
         [0042]    In the present embodiment, the lamp holder  100  is configured as a cup with a cross section which is circular. However, it also can be taken into consideration that in a second embodiment not shown, the lamp holder is configured as a cup with a square cross section, or other rotationally symmetric cups. Besides, in a third embodiment not shown, the body part also can have a cylindrical profile. 
         [0043]      FIG. 2  shows a 3D exploded view of the second housing of the lamp holder as shown in  FIG. 1 . The body part  21  and the assembling part  22  which can be made from the same or different metals are manufactured through different processes. In order to ensure that the body part  21  and the assembling part  2  can be stably assembled as en entirety, a rigid material is particularly chosen for manufacturing the body part  21  and the assembling part  22 . In the present embodiment, the body part  21  is configured as a cup-shaped metal stamping part, and the assembling part  22  is configured as a metal extrusion part. In order to ensure good heat dissipation effect and small dead weight of the lamp holder  100 , the body part  21  and the assembling part  22  are preferably made from aluminum. 
         [0044]    The inner circumferential wall A 1  of the first housing  1  defines an accommodation cavity  10  for placing the lighting module  201 . Corresponding to the section of the accommodation cavity  10 , the assembling part  22  is configured as a ring part. On an inner wall of the assembling part  22 , three grooves  22 . 1  distributed uniformly in the circumferential direction are formed. The grooves  22 . 1  can be configured as accommodation grooves for receiving fasteners such as screws or the like, as a result, the lamp holder  100 , especially the assembling part  22 , can be ensured to be in fixed connection with parts which need to be fixed in the lamp holder  100 . 
         [0045]    In another embodiment not shown, the number of the grooves can be two or more than three, and the grooves also can be configured as thread grooves or grooves of other types. 
         [0046]      FIG. 3  shows a 3D view of the second housing  2  as shown in  FIG. 1  after assembling. In order to decrease the number of parts of the lamp holder and reduce the manufacturing cost, the body part  21  and the assembling part  22  can be installed together merely in a manner of interference fit without additional fastener. Thus, the fixed connection manners such as soldering, bonding or bolted connection for integrating the body part  21  and the assembling part  22  can be omitted. 
         [0047]    For instance, the body part  21  and the assembling part  22  can be installed together in a manner of heat expansion and cold contraction. After the assembling part  22  is put into a major-diameter end of the body part  21  which expands with heat, the body part  21  is cooled to contract radially inwardly. Consequently, an end region of the body part  21  facing to the light emergent side of the lighting module, i.e. the end region of the body part  21  oriented upwardly, surrounds the assembling part  22 , and meanwhile, an outer circumferential wall of the assembling part  22  is against the inner circumferential wall of the body part  21 . 
         [0048]    Other processes also can be taken into consideration to install the body part  21  and the assembling part  22  together, for example, it can be realized with the aid of stamping. 
         [0049]      FIG. 4  shows a 3D exploded view of an illuminating device  200  according to the present invention. Apart from the lamp holder  100  already shown in  FIG. 1 , the lighting module  201  which needs to be installed together with the lamp holder  100  is also shown, comprising a driver  201 . 1 , a support  201 . 2 , a light engine  201 . 3 , a lens  201 . 4  and a lamp cover  201 . 5 . The above parts are installed in turn and inserted into the lamp holder  100  so as to form the complete illuminating device  200 . 
         [0050]    The above is merely preferred embodiments of the present invention but not to limit the present invention. For the person skilled in the art, the present invention may have various alterations and changes. Any alterations, equivalent substitutions, improvements, within the spirit and principle of the present invention, should be covered in the protection scope of the present invention. 
       LIST OF REFERENCE SIGNS 
       [0000]    
       
           1  first housing 
           11  stop portion 
           2  second housing 
           21  body part 
           22  assembling part 
           22 . 1  groove 
           10  accommodation cavity 
           100  lamp holder 
           200  illuminating device 
           201  lighting module 
           201 . 1  driver 
           201 . 2  support 
           201 . 3  light engine 
           201 . 4  lens 
           201 . 5  lamp cover 
         A 1  inner circumferential wall of the first housing