Patent Publication Number: US-2023156964-A1

Title: Heat sink and converter comprising same

Description:
TECHNICAL FIELD 
     The present invention relates to a heat sink, and more particularly, to a heat sink including a heat pipe and a converter module comprising the same. 
     BACKGROUND ART 
     In order to dissipate heat from products that generate a lot of heat, such as converters, various methods such as various fins and fans, thermoelectric elements, cooling water circulation, and heat pipes have been used. 
     The heat dissipation fin is a heat exchange device being formed in the form of a plurality of thin plates in order to enlarge the heat dissipation surface, and a heat pipe is a pipe-shaped heat exchange device that includes a working fluid inside to efficiently transfer heat between an interface between two solids by combining the principles of thermal conductivity and phase transition. 
     When a heat dissipation fin is used for heat dissipation of a DC-DC converter installed in a battery pack, the heat dissipation fin is exposed to the outside and there is a risk of burns when touched by a person&#39;s hand. In order to prevent the risk of burns, the battery pack should be placed in a position where a person&#39;s hand does not touch the heat dissipation fins, or a notice warning the risk of burns must be attached. 
     A heat dissipation method is required to prevent such a risk of burns. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Technical Subject 
     The technical problem to be solved by the present invention is to provide a heat dissipation substrate including a heat pipe and a method of manufacturing the heat dissipation substrate. 
     The subjects of the present invention are not limited to the subjects mentioned above, and other subjects not mentioned will be clearly understood by those skilled in the art from the following description. 
     Technical Solution 
     In order to solve the above technical problem, a heat sink according to an embodiment of the present invention comprises: a main heat sink; a heat pipe being mounted in a groove being formed on one surface of the main heat sink; a heat dissipation member being formed at an upper portion of the heat pipe to transfer heat being generated in the heat generation component to the heat pipe; and an elastic member being mounted in a space formed inside the heat dissipation member for applying pressure to the main heat sink. 
     In addition, the elastic member may include: an elastic unit being contracted by a pressure applied when the heat dissipation member and the main heat sink are coupled to each other; and a pressure pressing unit for applying a pressure being condensed according to the contraction of the elastic unit to the main heat sink. 
     In addition, the thickness of a portion of the main heat sink to which pressure is applied by the elastic member may be thinner than the thickness of other portions. 
     In addition, it may include a battery pack  900  coupling the heat dissipation member and the main heat sink. 
     In addition, it may include a thermally conductive pad being formed at an upper portion of the heat dissipation member to transfer heat being generated in the heat generation component to the heat dissipation member. 
     In addition, it may include a heat dissipation fin being disposed in other surface of the main heat sink. 
     In addition, an extension direction of the heat dissipation fin may be the same as an extension direction of the heat pipe. 
     In order to solve the above technical problem, a converter module according to an embodiment of the present invention comprises: a printed circuit board on which a plurality of components performing voltage conversion are mounted; a heat sink that serves as a contact surface in contact with the external device when the converter module is mounted on an external device and radiates heat being generated in the component; and a housing covering the outside of the converter module, wherein the heat sink comprises: a main heat sink; a heat pipe being mounted in a groove being formed on one surface of the main heat sink; a heat dissipation member being formed at an upper portion of the heat pipe to transfer heat being generated in the component to the heat pipe; and an elastic member being mounted in a space formed inside the heat dissipation member to apply pressure to the main heat sink, and wherein the main heat sink is in contact with a contact surface of an external device to which the converter module is mounted by the pressure applied from the elastic member. 
     In addition, at least some components among the plurality of components is disposed at a position corresponding to a lower portion when the converter module is mounted on an external device, and the extension direction of the heat pipe may be disposed in an up and down direction when the converter module is mounted on an external device. 
     In addition, the elastic member may include: an elastic unit being contracted by pressure being applied when the heat dissipation member and the main heat sink are coupled; and a pressure pressing unit for applying a pressure being condensed according to the contraction of the elastic unit to the main heat sink. 
     In addition, the thickness of a portion to which pressure is applied by the elastic member of the main heat sink may be thinner than the thickness of other portions. 
     Advantageous Effects 
     According to embodiments of the present invention, it is possible to increase safety for users by preventing the risk of burns, and it is possible to make the product slimmer and lighter. 
     The effect according to the invention is not limited by the contents exemplified above, and more various effects are included in the present specification. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    illustrates a heat sink according to an embodiment of the present invention. 
         FIG.  2    illustrates a converter module to which a heat sink according to an embodiment of the present invention is applied. 
         FIG.  3    is a view illustrating before and after shrinkage of the elastic member of the heat sink according to an embodiment of the present invention. 
         FIGS.  4  and  5    are diagrams for explaining that a heat dissipation fin is being mounted on a heat sink according to an embodiment of the present invention. 
         FIGS.  6  and  7    illustrate the inside of a converter module according to an embodiment of the present invention. 
         FIG.  8    illustrates a converter module according to an embodiment of the present invention including a housing. 
         FIGS.  9    (A) and (B) are diagrams illustrating a form in which a converter module according to an embodiment of the present invention is being mounted on a battery pack. 
     
    
    
     BEST MODE 
     Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. 
     However, the technical idea of the present invention is not limited to some embodiments to be described, but may be implemented in various forms, and within the scope of the technical idea of the present invention, one or more of the constituent elements may be selectively combined or substituted between embodiments. 
     In addition, the terms (including technical and scientific terms) used in the embodiments of the present invention, unless explicitly defined and described, can be interpreted as a meaning that can be generally understood by a person skilled in the art, and commonly used terms such as terms defined in the dictionary may be interpreted in consideration of the meaning of the context of the related technology. 
     In addition, terms used in the present specification are for describing embodiments and are not intended to limit the present invention. 
     In the present specification, the singular form may include the plural form unless specifically stated in the phrase, and when described as “at least one (or more than one) of A and B and C”, it may include one or more of all combinations that can be combined with A, B, and C. 
     In addition, in describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are merely intended to distinguish the components from other components, and the terms do not limit the nature, order or sequence of the components. 
     And, when a component is described as being ‘connected’, ‘coupled’ or ‘interconnected’ to another component, the component is not only directly connected, coupled or interconnected to the other component, but may also include cases of being ‘connected’, ‘coupled’, or ‘interconnected’ due that another component between that other components. 
     In addition, when described as being formed or arranged in “on (above)” or “below (under)” of each component, “on (above)” or “below (under)” means that it includes not only the case where the two components are directly in contact with, but also the case where one or more other components are formed or arranged between the two components. In addition, when expressed as “on (above)” or “below (under)”, the meaning of not only an upward direction but also a downward direction based on one component may be included. 
       FIG.  1    illustrates a heat sink according to an embodiment of the present invention. 
     The heat sink  100  according to an embodiment of the present invention comprises: a main heat sink  110 ; a heat pipe  120 , a heat dissipation member  130 , and an elastic member  150 , and it may include a battery packs  900  and  140 , and a heat conduction pad  160 . 
     A groove being formed on one surface is formed in the main heat sink  110 , and the heat pipe  120  is mounted in the groove. The cross-sectional area of the groove being formed in the main heat sink  110  is the same as the heat pipe  120  or is formed as wide as a predetermined value, and the heat pipe  120  is press-fitted into the groove to be closely in contact with an inner surface of the groove, and is mounted on the heat sink  100 . The heat pipe  120  may be press-fitted into the groove to have the same height as the height of the main heat sink  110 . 
     Since the heat dissipation efficiency is increased by using the heat pipe  120 , sufficient heat dissipation is possible without using the heat dissipation fins. When using a heat sink fin, the heat sink fin must be exposed to the outside, but since there is no need to use a heat dissipation fin by using the heat pipe  120 , the module including the heat sink  100  can be mounted inside the packaged product without exposing to the outside. Through this, the safety is increased, and it is possible to make the product slimmer and lighter. 
     The heat dissipation member  130  is formed at an upper portion of the heat pipe  120  to transfer heat being generated in the heat generation component to the heat pipe  120 . The heat dissipation member  130  is formed at an upper portion of the heat pipe  120  to transfer heat generated in a heat generation component that is not in direct contact with the main heat sink  110  on which the heat pipe  120  is formed to the heat pipe  120 . Here, the heat dissipation member  130  may serve as a sub heat sink. The heat dissipation member  130  may be formed of a metal having high thermal conductivity, such as aluminum. The height of the heat dissipation member  130  may vary depending on the distance between the heat sink  100  and the heat generation component. 
     The heat dissipation member  130  may be coupled to the main heat sink  110  through the battery packs  900  and  140 . The heat dissipation member  130  may be coupled to the main heat sink  110  through screw-coupling using a plurality of battery packs  900  and  140  as shown in  FIG.  2   . At this time, the battery pack  900  may be formed to have a coupling force that can withstand the pressure to expand the elastic member  150  being generated during coupling. The battery packs  900  and  140  may be coupled in various ways, such as a member capable of fit-coupling together. 
     The elastic member  150  is mounted in the space formed inside the heat dissipation member  130  and applies pressure to the main heat sink  110 . An internal space in which the elastic member  150  can be mounted is formed inside the heat dissipation member  130 , and the elastic member  150  is mounted in the internal space of the heat dissipation member  130 , but it is contracted by a pressure applied thereto when the heat dissipation member  130  is coupled to the main heat sink  110 , and a pressure condensed according to the contraction, that is, a force to be expanded, is applied to the main heat sink  110 . 
     The elastic member  150  may include: an elastic unit  151  being contracted by the pressure applied when the heat dissipation member  130  and the main heat sink  110  are coupled; and a pressure pressing unit  152  that applies a pressure being condensed according to the contraction of the elastic unit  151  to the main heat sink. The elastic unit  151  has a fan shape, but it may be deformed into an elliptical shape when contracted. 
     The elastic member  150  may be formed of a material having elasticity. For example, it may be formed of a metal material such as SUS, or may be formed of various other materials having elasticity. Since the elastic member  150  is in contact with the heat dissipation member  130  and the main heat sink  110 , it may be formed of a material having high thermal conductivity. Through this, not only pressure transfer but also heat conduction may be performed. The application of pressure by the elastic member  150  to the main heat sink  110  will be described in detail later. 
     As shown in  FIG.  2   , the heat sink  100  according to an embodiment of the present invention may be applied to a product. 
     The heat sink  100  may be applied to, for example, a DC-DC converter that transmits power to a battery cell, and serves to reduce heat generated from a heat generation component of the DC-DC converter. A DC-DC converter includes various components such as a switch, a coil forming a transformer, and a capacitor. In particular, a lot of heat is generated in the coil and switch, and the coil and the switch have different product sizes, and as shown in  FIG.  2   , the FET being used as the switch has a considerably smaller product size than the coil. Therefore, the coil may be in direct contact with the heat sink  100 , but components such as switches are difficult to be directly in contact with the main heat sink  110 , so it must be in indirect contact with the main heat sink  110 , in which the heat pipe  120  is mounted, through the heat dissipation member  130 . 
     The heat generation component  220 , such as a switch being mounted on the printed circuit board  210 , transfers heat to the heat pipe  120  through the heat dissipation member  130 . At this time, a heat conduction pad  160  may be included between the heat generation component  220  and the heat dissipation member  130 . A thermal pad is a pad made of a material with high thermal conductivity, and it is formed between the heat generation component  220  and the heat dissipation member  130 , it acts as a buffer between the heat generation component  220  and the heat dissipation member  130  while transferring heat being generated in the heat generation component  220  to the heat dissipation member  130 . 
     The heat transferred from the heat generation component  220  to the main heat sink  110  in which the heat pipe  120  is formed through the heat conduction pad  160  and the heat dissipation member  130  is discharged to the outside, and at this time, if the product to which the heat sink  100  is applied is a single package module, heat must be transferred to the outside through the surface of the external device on which the package module is mounted. For example, a product to which the heat sink  100  is applied may be a DC-DC converter module being mounted on a battery pack. The heat sink  100  transfers heat being generated in a DC-DC converter module to the housing of the battery pack, so that it is discharged to the outside through the housing of the battery pack. For this, the heat sink  100  must be in contact with the housing of the battery pack, and the contact should be maintained. An elastic member  150  is used so as to maintain the contact with the contact surface  310  of an external device such as a housing of a battery pack. 
     The heat dissipation member  130  may not be applied one by one to correspond to one component  220 , but may be formed to correspond to a plurality of components  220 . Since it is formed to correspond to a plurality of parts, it may be formed to a size that can form an internal space, and through this, it is possible to form a sufficient internal space in which the elastic member can be formed. For example, as shown in  FIG.  2   , the heat dissipation member  130  may be formed at a lower portion of two or more components, and it may be formed at a lower portion of a plurality of components, such as four or six. The inner space may be formed in a groove shape. A locking step or a seating portion on which the elastic member  150  is caught may be formed in an inner space so that the elastic member  150  is not separated, and it may be formed to fit the width of the elastic member  150  so as not to deviate in the other direction by the force applied when the elastic member is contracted in a height direction. The elastic member  150  may contract or expand only in a height direction depending on the shape of the inner space. 
     As described previously, when the heat dissipation member  130  is coupled to the main heat sink  110  through the battery packs  900  and  140 , and the like, the pressure being applied to the elastic member  150  is applied to the main heat sink  110 , and a force is applied to the main heat sink  110  to the other surface which is an opposite surface to the one surface on which the elastic member  150  is formed, that is, toward the contact surface of the external device so that the main heat sink  110  may maintain contact with the contact surface  310  of the external device. 
     The shape of the elastic member  150  may vary depending on the size of the internal space being formed in the heat dissipation member  130 , but includes an elastic unit  151  that is contracted in a height direction by the applied pressure and a pressure pressing unit  152  for which a force is applied in the direction toward the main heat sink  110 . The elastic member  150  may be mounted in the form of one clip in the inner space or may be formed in plurality. 
     The thickness of the portion of the main heat sink  110  to which the pressure is applied by the elastic member  150  may be formed to be thinner than the thickness of other portions. The thickness of the corresponding position may be formed thinner than the thickness of other parts so as to maintain contact with the contact surface  310  of the external device by the pressure being applied by the elastic member  150 . Since the thickness is formed thinner than other portions, the force can be concentrated on the corresponding portion, and because the force is locally applied to the corresponding portion the main heat sink  110  is pushed toward the contact surface  310  of the external device so that the contact can be maintained. 
       FIG.  3    is a diagram for explaining a force applied to the elastic member  150  when the heat dissipation member  130  and the main heat sink  110  are coupled, and as a result, how a force is applied toward the surface opposite to the surface in which the main heat sink  110  is in contact with the elastic member  150 . 
     Before the heat dissipation member  130  is coupled to the main heat sink  110 , since no force is applied to the elastic member  150 , it is a stable state that neither contracts nor expands, and the elastic unit  151  maintains the original fan shape. The pressure pressing unit  152  also does not apply pressure to the main heat sink  110 . 
     The height of the elastic member  150  in a stable state may be higher than the height of the internal space being formed when the heat dissipation member  130  and the main heat sink  110  are coupled. By the pressure  310  being applied when the heat dissipation member  130  is coupled to the main heat sink  110  using the battery packs  900  and  140 , and the like, the elastic member  150  is pressed and the elastic unit  151  is contracted. At this time, the elastic unit  151  may be deformed from a fan shape to an elliptical shape. The force being condensed by the contraction of the elastic unit  151  is applied to the main heat sink  110  through the pressure pressing unit  152 , and a force  320  is applied to the main heat sink  110  in a direction toward the other surface. That is, a force is applied in a direction toward the contact surface of the external device, so that the main heat sink  110  may maintain contact with the contact surface of the external device. 
     A heat dissipation fin  400  may be disposed on the other surface of the main heat sink  110 . As described previously, it can be mounted inside an external device without using the heat dissipation fin  400  using the heat pipe  120 , but the heat dissipation fin  400  may be used in order to use an existing structure or to further increase the efficiency of heat dissipation. In the case of using the heat dissipation fin  400 , when the arrangement direction of the heat pipe  120  and direction of the fin of the heat dissipation fin  400  are formed perpendicular to each other, since the heat flow can be obstructed, as shown in FIG.  5 , by disposing the direction of the heat pipe  120  and direction of the fin of the heat dissipation fin  400  in the same way, the heat dissipation efficiency can be improved by making the directions of heat flow to be the same. That is, the extending direction of the heat dissipation fin  400  may be formed in the same direction as the extending direction of the heat pipe  120 . 
     A converter module  200  according to an embodiment of the present invention comprises: a printed circuit board  210  on which a plurality of components performing voltage conversion are mounted; a heat sink  100  for dissipating heat being generated from the component and becoming a contact surface that comes into contact with an external device when the converter module is mounted on the external device; and a housing for covering the outside of the converter module. Since a detailed description of the heat sink  100  comprising the converter module  200  according to an embodiment of the present invention corresponds to the detailed description of the heat sink  100  according to an embodiment of the present invention previously described with reference to  FIGS.  1  to  5   , hereinafter, overlapping descriptions will be omitted. 
     The converter module  200  according to an embodiment of the present invention may be formed as a package module on one heat sink  100  as shown in  FIG.  6   . The converter module  200  may be a DC-DC converter and may include a plurality of components that perform voltage conversion. As shown in  FIG.  6   , it may include a plurality of coils  240  comprising the transformer and a switch  220  for switching the connection relationship of the coils for voltage conversion, and it may include one or more capacitors  250  and switch  230  and the like, and it may include a connection stage (not shown) being connected to the outside such as a battery. In addition, a coupling portion  260  that can be coupled when the converter module  200  is mounted to an external device may be formed. The converter module  200  may be screw-coupled with an external device using the battery pack  900 . 
       FIG.  7    illustrates a top view of the heat sink  100  in a direction toward an upper portion of a converter module  200  according to an embodiment of the present invention and a cross-sectional view taken along the A-A′ cross-section 
     At least some of the plurality of components mounted on the printed circuit board  210  is disposed at a position corresponding to the lower portion when the converter module  200  is mounted on an external device, and the direction of extension of the heat pipe  120  may be disposed in an up and down direction when the converter module  200  is mounted on an external device. That is, in order to increase the efficiency of heat dissipation, heat generation components among the components of the converter module  200  are mainly disposed at a lower side, and in order to transfer the heat being generated by the corresponding heat generation components toward an upper side, the heat pipe  120  being mounted on the heat sink  100  may be disposed so as to be disposed in an up and down direction  710 . 
     Components included in the converter module  200 , as shown in the cross-sectional view, are mounted on the printed circuit board  210 , and a small heat generation component  220  such as a switch being formed of an FET may be formed to be in contact with a heat sink structure comprising a main heat sink  110 , a heat pipe  120 , a heat dissipation member  130 , and an elastic member  150 . Here, the heat sink  100  may comprise: a main heat sink  110 ; a heat pipe  120  being mounted in a groove being formed in one surface of the main heat sink  110 ; a heat dissipation member  130  being formed at an upper portion of the heat pipe  120  to transfer heat being generated in the component to the heat pipe  120 ; and an elastic member  150  being mounted in a space formed inside the heat dissipation member  130  to apply pressure to the main heat sink  110 . Here, the main heat sink  110  may come into contact with a contact surface of an external device on which the converter module  200  is mounted by the pressure being applied from the elastic member  150 . 
     The elastic member  150  may include: an elastic unit  151  that is contracted by the pressure being applied when the heat dissipation member  130  and the main heat sink  110  are coupled; and a pressure pressing unit for applying a pressure condensed according to the contraction of the elastic unit  151  to the main heat sink  110 . Here, the thickness of the portion of the main heat sink  110  to which the pressure is applied by the elastic member may be formed to be thinner than the thickness of other portions. 
     Components of the converter module  200  are formed between the printed circuit board  210  and the heat sink  100 , and a housing  700  covering the printed circuit board  210  may be included. The housing  700  and the heat sink  100  of the converter module  200  in which the housing  700  is mounted are seen from the outside as shown in  FIG.  8   , and they can be installed as one module in an external device such as a battery pack through the coupling portion  260  being formed in the heat sink  100 . 
     The converter module  200  according to an embodiment of the present invention may comprise a battery pack  900  together with a battery cell  910  as shown in  FIG.  9   . The converter module  200  is mounted inside the battery pack  900 , but it may be disposed at a rear side the battery cell  910 . At this time, the converter module  200  may be coupled to the battery pack  900  through four coupling portions  260 . The converter module  200  is disposed on a rear surface  930  not on a front surface  920  of the battery pack  900 , and the heat sink  100  is also disposed to face the rear surface  930  of the battery pack  900  so that the heat being generated in the converter module  200  is transferred to the heat sink  100  and the rear surface  930  of the battery pack  900  and can be discharged toward the outside. As previously explained, the heat sink  100  is applied with force toward the rear surface  930  of the battery pack  900  by the elastic member  150  being formed in the heat sink  100 , and through this, contact with the rear surface  930  of the battery pack  900  is maintained so that it is possible to prevent the heat sink  100  from being separated and the like from the rear surface  930  of the battery pack  900 . At this time, the battery pack  900  is disposed at a predetermined distance from the wall surface so that heat may be smoothly dissipated to the back surface of the battery pack  900 . Heat dissipation efficiency may be increased by forming heat dissipation fins on an outer surface of the battery pack  900 . 
     As described above, in the present invention, specific matters such as specific components, and the like; and limited embodiments and drawings have been described, but these are only provided to help a more general understanding of the present invention, and the present invention is not limited to the above embodiments, and various modifications and variations are possible from these descriptions by those of ordinary skill in the art to which the present invention belongs. 
     Therefore, the spirit of the present invention should not be limited to the described embodiments, and not only the claims to be described later, but also all those with equivalent or equivalent modifications to the claims will be said to belong to the scope of the spirit of the present invention.