Patent Publication Number: US-2013247361-A1

Title: Method for manufacturing of an electric actuator

Description:
A method for manufacturing of an electric actuator, which actuator consists of an electric actuator arrangement that is sensible to heat and/or that generates heat, the actuator being put together to form a uniform organ, such as a light source, by coupling the electric actuator arrangement with an at least thermally conductive frame part. 
     Particularly e.g. in LED-lighting/light production putting together of the type of light sources described above is nowadays a problem, since the production is still based on e.g. manual manufacturing, wherein a separate LED component is being glued or fastened by a screw joint e.g. to an aluminium based frame part. When using a screw joint, between the LED component and the aluminium frame is usually installed furthermore a thermally conductive paste or tape. This kind of an intermediate layer is required due to the fact that the surface of aluminium is not totally level, which is why, despite the screw joint, there will be left air between the parts, which weakens thermal transmission. The thermally conductive paste or tape levels the surface roughness of the aluminium and forms a uniform heat transmitting substance layer between the parts in question. In this kind of an implementation, the aluminium frame acts thus as an element that cools the LED, in which connection it is characteristic that the better the cooling is at the back side of the LED, the brighter the LED illuminates thus also enabling as long as possible operating time thereof. An advantage of aluminium, being used as a part of the frame material, is its property of having a good thermal conductivity, whereby aluminium has a disadvantage first of all due to its thermal expansion and on the other hand due to its electric conductivity and even “extensive” thermal conductivity (high surface temperature) in certain implementations. Furthermore, aluminium needs usually to be separately painted or coated in order to prevent it from becoming oxidized. 
     It is the aim of the method according to the present invention to achieve a decisive improvement in the problems described above and thus to raise essentially the level of prior art. In order to carry out this aim, the method according to the invention is mainly characterized by that the actuator arrangement and the frame part are being coupled with each other in an integral manner by processing a manufacturing material forming the frame part in connection with the actuator arrangement. 
     As the most important advantages of the method may be mentioned simplicity and efficiency of the method itself and the actuators to be manufactured by the same, in which case a totally new kind of an actuator is made possible by exploiting a very usual processing as such, whereby the actuator has its electric actuator arrangement and thermally conductive and, when needed, electrically non-conductive frame part built together from manufacturing onwards. Thus a manual manufacturing of a LED light source e.g. as described in the beginning, can be avoided along with use of an extraordinary thermally conductive tape or paste that is usually needed in this context. 
     When applying the method according to the invention advantageously, a manufacturing material forming the frame part is being processed in connection with the actuator arrangement by exploiting mold technique, whereby the actuator arrangement is being sunk by its heat sensitive or thermally conductive surface at least partly inside the frame part. Thus, as a particularly advantageous embodiment particularly in putting together of a LED light source, at a bottom of the LED is being processed advantageously furthermore an at least thermally conductive composite material that is based on rubber and/or plastic, whereby thanks to its thermal transmission properties also heat strain directed to the LED component during the processing can be kept adequately low. When exploiting the method advantageously further, the actuator arrangement is being coupled with electronics operating the same at least partly internally in the frame part by exploiting in the processing an essentially electrically non-conductive manufacturing material, which for its part minimizes significantly manufacturing costs. 
     The method according to the invention enables thus both technically and economically taken remarkable advantages when compared e.g. to the present manual manufacturing of LED light sources. The invention enables furthermore manufacturing of very accurate measured actuators that have furthermore a freedom in shape, whereby an advantage of the actuators is in addition to lightness, a finished appearance thereof from the manufacturing onwards as well as good dampproofness characteristics. 
     Other advantageous embodiments of the method according to the invention have been presented in the dependent claims related thereto. 
    
    
     
       In the following description, the invention is being illustrated in detail with reference to the appended drawings, in which 
       in  FIGS. 1   a - 1   d    
       are shown as exemplary cross sectional views two alternative compositions of a traditionally manufactured LED light source ( FIGS. 1   a  &amp;  1   b ), and as a front view and as a side view two traditional LED-components ( FIGS. 1   c  &amp;  1   d ), 
       in  FIGS. 2   a  and  2   b    
       is shown an advantageous actuator being enabled by the method according to the invention, such as a LED light source being manufactured by the method and being put together in two alternative ways, 
       in  FIGS. 3   a - 3   h    
       are shown some advantageous actuator compositions being based on the LED component shown in  FIG. 1   c  and manufactured by the method according to the invention as alternative embodiments in respect with the ones shown in  FIGS. 2   a  and  2   b,    
       in  FIGS. 4   a - 4   b    
       is shown an actuator based on the LED component according to figure ld as two alternative compositions, and furthermore 
       in  FIGS. 5   a - 5   c    
       are shown corresponding cross sectional views of three alternative compositions enabled by the method according to the invention, the compositions containing several electric actuator arrangements. 
     
    
    
     The invention relates to a method for manufacturing of an electric actuator, which actuator consists of an electric actuator arrangement  1  that is sensible to heat and/or that generates heat, the actuator being put together to form a uniform organ, such as a light source, by coupling the electric actuator arrangement with an at least thermally conductive frame part  2 . The actuator arrangement  1  and the frame part  2 ;  2 ′ are being coupled with each other in an integral manner by processing a manufacturing material forming the frame part  2 ;  2 ′ in connection with the actuator arrangement  1 . 
     In  FIGS. 1   a  and  1   b  is shown a usual LED light source, being put together by a traditional method manually, in which a LED component  1 ;  1 ′, as shown particularly in  FIG. 1   c , that consists of an aluminium frame  1   c , being equipped with contact surfaces V 1  on its upper surface  1   b  that has an electrically insulating surface treatment, and a diode  1   a , the LED component being coupled in the composition according to  FIG. 1   a  by a screw joint R with an aluminium frame  2 , inside of which is arranged in an integral and screened HE manner electronics E operating the LED component, whereby the electronics gets its current from a power source P. In the implementation according to  FIG. 1   a , the contact surfaces V 1  of the LED-component  1 ;  1 ′ are connected inside the aluminium frame  2  by electrically insulated SE conductors V with the electronics unit E. In the composition according to  FIG. 1   b , there has been exploited for its part a separate electronics unit E in respect with the aluminium frame  2 . In figure ld is shown an alternative LED light source with respect to the one shown in  FIG. 1   c , in which the contact surfaces V 1  are at the bottom surface of the LED component  1 ;  1 ′. 
     As an advantageous embodiment of the method according to the invention, the manufacturing material forming the frame part  2 ;  2 ′ is being processed in connection with the actuator arrangement  1  by exploiting mold technique. 
     Furthermore, as an advantageous embodiment of the method, the actuator arrangement  1  is being processed in connection with the manufacturing of the actuator particularly by its heat sensitive and/or heat generating surface B to be at least partly sunk inside the frame part  2 ′, which manifests itself from all of the appended exemplary drawings presenting actuators that are manufactured by the method according to the invention. 
     Furthermore as an advantageous embodiment of the method, as the manufacturing material of the frame part  2 ;  2 ′ or as a part thereof is being used thermosetting plastic, thermoplastic, vulcanized rubber and/or thermoplastic elastomer, which is being processed in connection with the actuator arrangement  1  by injection molding, die-casting or in a corresponding manner. 
     When the electric actuator assembly  1  comprises one or several heat generating electric actuators, such as LED components  1 ′ or like as presented in the appended drawings, at the bottom B thereof is being processed advantageously furthermore an at least thermally conductive composite material that is based on rubber and/or plastic. 
     In connection with the LED light source  1 ;  1 ′,  2  presented in  FIGS. 1   a  and  1   b , being based on manual manufacturing, there has been exploited electronics E, being coupled in an integral manner with the frame part, as explained above, and also on the other being apart from the frame part, the electronics being coupled with the LED component electrically. When applying the method according to the invention, a corresponding composition can be carried out by using thermally conductive plastic based manufacturing material forming the frame part  2 ;  2 ′ e.g. on the principles presented in  FIGS. 2   a  and  2   b , in which case due to a more or less electrically conductive frame part  2 ′, the conductors V, connecting the LED component  1 ′ and the electronics E operating the same, exist in an air space I in the frame part or the conductors being coated or covered by an electrically insulating material SE. 
     Particularly, as an alternative embodiment of the method with respect to the one described above, with reference e.g. to the compositions presented e.g. in  FIGS. 3   a - 3   h , the actuator arrangement  1  is being coupled with the electronics E operating the same at least partly internally inside the plastic based frame part  2 ′ by using in the processing an essentially electrically non-conductive manufacturing material, such as a manufacturing material containing e.g. ceramic, organic and/or mineral based substance. 
     As a further advantageous embodiment of the method in this context, the electrical conductors V and/or the electronics E, being coupled with the actuator arrangement  1  are being processed in an integral manner inside the frame part  2 ′, in which case there is no need for the protective insulation in the first place. 
     Furthermore as an advantageous embodiment of the method, particularly with reference to the compositions presented in  FIGS. 3   c  and  4   b , in connection with the processing, a cooling insert M made of metal, such as aluminium, is being installed inside the frame part  2 ;  2 ′. In this way it is possible to improve furthermore the thermal transmission/cooling properties of the frame part  2 ′. 
     Furthermore as an advantageous embodiment of the method, a two- or multi-component manufacturing is being exploited in the processing e.g. in order to achieve different parts of the frame part  2 ′ to have thermal conductivity and/or electrical conductivity characteristics deviating from each other or for corresponding purpose. In the appended drawings, in the manufacturing of the compositions according to  FIGS. 3   d  and  3   e , there has been applied the technique above by a material zone LS, being processed inside the frame part  2 ′ that makes thermal transmission more efficient. Accordingly, in the composition according to  FIG. 3   h , there has been processed in this way in the center part of the frame part  2 ′ a material zone LS that is thermally non-conductive and possibly also electrically non-conductive, in which case on the outer surface of the frame part there has been processed a material zone SH comprising cheaper customary plastics. 
     In connection with an actuator being manufactured according to the method, it is furthermore possible to exploit implementations known as such from prior art e.g. on the principles presented e.g. in  FIGS. 3   f ,  3   g  and  5   c , in which case in connection with an actuator  1 ;  2 ′, being manufactured by the method according to the invention, is being coupled e.g. by a screw joint R possibly together with a thermally conductive paste or a tape layer L a metallic installation rail A e.g. made of aluminium, which for its part makes thermal transmission thus even more efficient. 
     The compositions presented in  FIGS. 4   a  and  4   b  are manufactured by using a LED component  1 ′ according to  FIG. 1   d , in which the contact surfaces V 1  are at the bottom surface of the component. In this kind of an implementation, an optimum composition is achieved particularly with a view to its moisture isolation characteristics, because all electrical operations of the actuator are thus closed inside the frame part  2 ′ in a totally protected manner during the manufacturing process of the actuator. Furthermore in  FIGS. 5   a  and  5   c  are presented light units consisting of several LEDs  1 ′, in which there has been used either external or integral electronics E. This kind of a lighting unit can be coupled by customary screw joints R as such e.g. on the principle shown in  FIG. 5   c  and, when needed, by using a thermally insulating paste or tape L, with an actual installation rail A. 
     It is clear that the invention is not limited to the embodiments presented or described above, but instead it can be modified within the basic idea of the invention in very many ways. It is thus first of all clear that the method according to the invention can be exploited in manufacturing of actuators containing most heterogeneous electrical components, when there is a need to couple particularly an electrical actuator with a thermally conductive frame part in an integral manner. It is thus clear that the electric actuator does not need to generate heat as such, but instead it can be merely sensitive to heat, so that it does not forfeit its characteristics due to excessive heat, when it is being soldered or processed according to the invention. The method according to the invention can thus also be exploited in connection with production of other types of light sources as well as in connection with most heterogeneous heat generating electrical components, such as electric circuits, microprocessors etc. The method according to the invention can also be varied with a view to manufacturing techniques by exploiting differing manufacturing processes e.g. depending on the manufacturing materials, such as e.g. powder technique, melt processing technique etc.