Patent Publication Number: US-9429063-B2

Title: Cylinder block

Description:
CROSS-REFERENCE(S) TO RELATED APPLICATIONS 
     The present application claims priority to Korean Patent Application No. 10-2014-0030035, filed on Mar. 14, 2014, which is incorporated herein by reference in its entirety. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     Exemplary embodiments of the present invention relate to a cylinder block, particularly, to a cylinder block capable of improving cooling performance and fuel efficiency of an engine by forming a heat sink in a water jacket provided within the cylinder block. 
     2. Description of Related Art 
     A vehicle engine is aimed at improving fuel efficiency and performance by increasing cooling efficiency of a cooling system thereof all over the world. In a case of raising output of a water pump or increasing an amount of cooling water in order to enhance the cooling efficiency, there is a problem in that fuel efficiency of the engine is deteriorated since driving torque is increased and an additional load is applied to the engine. On the contrary, in a case of lowering output of the water pump or decreasing an amount of cooling water in order to enhance fuel efficiency, there is a problem in that cooling performance of the engine is deteriorated. 
     Meanwhile, an HPDC (HIGH PRESSURE DIE CASTING), which is a method of manufacturing a typical cylinder block, has a difficulty in manufacturing a cylinder block having different mixed materials using a core due to the nature in which high pressure is applied to a cast during casting the cylinder block. However, when a slat core is applied to the HPDC, the cylinder block having different mixed materials is expected to be manufactured. 
     The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art. 
     BRIEF SUMMARY 
     Various aspects of the present invention are directed to providing a cylinder block capable of simultaneously improving cooling efficiency and fuel efficiency by additionally forming a heat sink in a water jacket. 
     Other objects and advantages of the present invention can be understood by the following description, and become apparent with reference to the exemplary embodiments of the present invention. Also, it is obvious to those skilled in the art to which the present invention pertains that the objects and advantages of the present invention can be realized by the device as claimed and combinations thereof. 
     In accordance with an exemplary embodiment of the present invention, a cylinder block including a water jacket for maintaining an engine at a proper temperature during operation thereof, includes a plurality of cylinders formed within the cylinder block so that a number of pistons are respectively inserted into the cylinders, and a heat sink formed in the water jacket provided to enclose side surfaces of the plural cylinders. 
     The heat sink may be formed a portion of upper sides of the plural cylinders, the heat sink may have a band shape and be continuously formed along width directions of the plural cylinders, the heat sink may have a curvature formed along surfaces of the cylinders and be bent such that a rectangular concavo-convex structure is continuously formed along the width directions of the plural cylinders, and the water jacket may be formed to be capable of communicating with a water jacket provided to cylinder heads mounted above the cylinders. 
     The water jacket may be divided into a first water jacket enclosing sides of the cylinders in width directions thereof and a second water jacket enclosing the other sides of the cylinders in the width directions thereof, an inlet may be extendedly formed through which cooling water is introduced from one side of the first water jacket to the water jacket, an outlet may be extendedly formed through which the cooling water in the water jacket is discharged from one side of the second water jacket, and the heat sink may be formed in each of the first and second water jackets. 
     The water jacket and the heat sink may have different materials from each other, and the heat sink may be cast simultaneously with the water jacket using a salt core. 
     The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description, which together serve to explain certain principles of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view illustrating a cylinder block according to an exemplary embodiment of the present invention. 
         FIG. 2  is a cross-sectional view illustrating a principal part of the cylinder block in  FIG. 1 . 
     
    
    
     It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment. 
     In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing. 
     DETAILED DESCRIPTION 
     Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that the present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims. 
       FIG. 1  is a perspective view illustrating a cylinder block according to an exemplary embodiment of the present invention.  FIG. 2  is a cross-sectional view illustrating a principal part of the cylinder block in  FIG. 1 . 
     As shown in  FIGS. 1 and 2 , the cylinder block according to the exemplary embodiment of the present invention including a water jacket  100  for maintaining an engine at a proper temperature during operation thereof includes a plurality of cylinders  200  formed within the cylinder block so that a number of pistons are respectively inserted into the cylinders  200  and a heat sink  300  formed in the water jacket  100  provided to enclose side surfaces of the plural cylinders  200 . 
     In an exemplary embodiment of the present invention, the heat sink  300  is formed a portion of upper sides of the plural cylinders  200 . The heat sink  300  has a band shape and is continuously formed along width directions of the plural cylinders  200 . 
     In this case, the heat sink  300  has a curvature formed along surfaces of the cylinders  200  and has a stepped cross-section configured by being bent such that a rectangular concavo-convex structure is continuously formed. 
     Since the heat sink  300  has the stepped cross-section, a heat transfer surface area thereof is maximized so that heat transfer from the heat sink  300  to cooling water is maximized. 
     In addition, the water jacket  100  is formed to be capable of communicating with a water jacket provided to cylinder heads mounted above the cylinders  200 . The water jacket  100  is divided into a first water jacket  110  enclosing sides of the cylinders  200  in the width directions thereof and a second water jacket  120  enclosing the other sides of the cylinders  200  in the width directions thereof. 
     An inlet I is extendedly formed through which cooling water is introduced from one side of the first water jacket  110  to the water jacket  100 , and an outlet O is extendedly formed through which the cooling water in the water jacket  100  is discharged from one side of the second water jacket  120 . 
     That is, cooling water is introduced into the first water jacket  110  through the inlet I, is moved to the water jacket through the first water jacket  110 , and is then discharged through the extended outlet O from the second water jacket  120 . 
     The heat sink  300  is formed in each of the first and second water jackets  110  and  120  to maximally receive heat generated in a combustion chamber B, namely in a space between the uppermost end of each of the cylinders  200  and the associated cylinder head. 
     The heat transferred to the heat sink  300  is transferred to cooling water moving between the water jacket  100  and another water jacket and is then transferred to the outside via a cooling system. 
     The cylinder block having the above configuration according to an exemplary embodiment of the present invention is manufactured such that the water jacket  100  and the heat sink  300  have different materials from each other, in order to transfer more heat to the heat sink  300 . That is, the present invention selects a material such that the heat sink  300  has a heat transfer coefficient larger than the water jacket  100 . 
     In addition, the cylinder block of the present invention is manufactured such that the heat sink  300  is cast simultaneously with the water jacket  100  using a salt core. 
     Since the cylinder block is cast such that the heat sink  300  is formed in the water jacket  100  using the salt core, the cylinder block applying the techniques of the present invention may be manufactured without a considerable change in a production line of the cylinder block according to the related casting method. Thus, it may be possible to reduce production costs and increase productivity. 
     In addition, since the heat sink  300  may be formed in an inner space of the water jacket  100  without restriction on an installation position, the heat sink  300  may be formed in the vicinity of the high-temperature combustion chamber or in a part in which cooling must be greatly performed. Consequently, cooling may be locally performed and cooling efficiency may be increased. 
     Ultimately, in accordance with the present invention, it may be possible to improve cooling performance without an increase in a capacity of an additional water pump and thus improve fuel efficiency of an internal combustion engine. 
     In accordance with a cylinder block according to the exemplary embodiments of the present invention, it may be possible to improve cooling efficiency of the cylinder block without an increase in a capacity of a water pump or an amount of cooling water. 
     In addition, it may be possible to enhance the cooling efficiency by mounting a heat sink to a part to which heat is relatively significantly transferred. That is, it may be possible to intensively cool a combustion chamber. 
     In addition, since the heat sink is cast simultaneously with a water jacket via a salt core method, the heat sink may be simply formed. 
     Moreover, since the cooling efficiency is enhanced without an increase of an additional load for circulation of cooling water, fuel efficiency of an engine may be improved. 
     Furthermore, since the heat sink may be formed in the water jacket without a considerable change in a casting method of manufacturing an existing cylinder block, the present invention may be simply applied thereto and have high productivity. 
     For convenience in explanation and accurate definition in the appended claims, the terms “upper”, “lower”, “inner” and “outer” are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures. 
     The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.