Patent Application
20200232415
The present invention relates to an engine with a reduced cooling loss. More particularly, the present invention relates to an engine improved with a fuel consumption by reducing a cooling loss without a large design change of an engine.
In a combustion chamber, a heat loss may be expressed as follows.
Q=hA(Tgas−Twall)Δt
Here, Q represents a heat transfer, h represents a heat transfer coefficient, A represents a heat exchange area of the combustion chamber, (Tgas-Twall) represents a temperature difference of a combustion gas and an internal wall, and Δt represents an elapsed time.
In other words, it may be confirmed that the heat loss due to the heat transfer is larger as the combustion chamber area is larger.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and may 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.
Various aspects of the present invention are directed to providing the engine reducing the cooling loss and obtaining an enhancement of a fuel consumption by reducing a combustion chamber heat transfer area.
An engine with the reduced cooling loss according to various aspects of the present invention are directed to providing an engine in which a cylinder block and a cylinder head are combined, wherein an engine displacement chamber volume of the cylinder block is 300 cc-700 cc, and wherein a compression ratio between the volume of the engine displacement chamber and the volume of the entire combustion chamber is 10.0 or more:1.
The engine may be a gasoline engine.
The engine may include an intake valve and an exhaust valve, and a height from a bottom surface of the intake valve and the exhaust valve to a contact portion in contact with a valve seat may be 0.6 mm to 1.0 mm.
The bottom surface of the intake valve and the exhaust valve may be a flat shape.
According to the engine with the reduced cooling loss according to an exemplary embodiment of the present invention, without a design change of a conventional engine, the cooling loss may be reduced and the fuel consumption may be enhanced by reducing the combustion chamber heat transfer area.
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.
It may 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 particularly 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.
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 other hand, 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.
In the following detailed description, only certain exemplary embodiments of the present invention have been shown and described, simply by way of illustration.
As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention
Throughout the specification, the same reference numerals represent the same components.
In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity.
In addition, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising”, will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.
An exemplary embodiment of the present invention will hereinafter be described in detail with reference to the accompanying drawings.
Referring to
The volume 20 of the cylinder head 40 may be defined by a virtual surface X connecting a lower surface of the cylinder head 40 and a volume formed by the cylinder head 40.
The volume 30 of the cylinder block 50 may be defined by the virtual surface X connecting the lower surface of the cylinder head 40 and the volume formed by the cylinder block 50 and the piston 12.
The entire combustion chamber volume may be defined by a sum of the volume 20 of the cylinder head 40 and the volume 30 of the cylinder block 50 when a piston is positioned on a top-dead center (TDC) as shown in
The volume of the engine displacement chamber of the cylinder block 50 is 300 cc-700 cc, and a compression ratio of the engine displacement chamber and the entire combustion chamber volume is 10.0 or more:1, wherein the engine displacement chamber is a chamber in which a piston of the engine reciprocates in the engine and is calculated from the bore, i.e., diameter of a cylinder and a stroke, i.e, a distance in which the piston travels between the top dead center (TDC) and the bottom dead center (BDC) in the engine.
The engine displacement chamber does not include the volume of the entire combustion chamber. In this configuration, if an engine has a compression ratio of 10:1 and the engine displacement chamber is 500 cc, then the entire combustion chamber volume is 50 cc.
The volume 20 of the cylinder head 40 may be 40%-70% of the entire combustion chamber volume.
The engine 10 with the reduced cooling loss according to an exemplary embodiment of the present invention is designed to reduce the cooling loss and to obtain the enhancement of the fuel consumption by reducing the combustion chamber area.
Also, the engine 30 may be a gasoline engine, and for ease of understanding, spark plugs and the like are omitted in the drawings.
The conventional diesel engine has a flat bottom so that there is not much a margin to reduce the volume of the cylinder head, therefore an application of the engine with the reduced cooling loss according to an exemplary embodiment of the present invention is not easy. Accordingly, the engine 30 may be the gasoline engine.
As the engine configured for reducing the cooling loss by the reducing the volume of the cylinder head, the engine of which the engine displacement chamber is 300 cc-700 cc is limited as an experiment.
Also, since the combustion chamber volume of the engine having the relatively low compression ratio is sufficiently large, a margin configured for improving the fuel consumption by reducing the combustion chamber area of the cylinder head is not large so that the engine with the reduced cooling loss according to an exemplary embodiment of the present invention may be limited to the engine of which the compression ratio is 10.0 or more.
As an attempt to reduce the heat transfer area of the cylinder head 40, based on a conventional engine specification, the area of the entire combustion chamber, the area improvement amount, and the volume was obtained by reducing the height of the lower surface X of the cylinder head 40.
As shown in the table of
In the table of
As an attempt to reduce the heat transfer area of the cylinder head 40, the area of the entire combustion chamber and a surface improvement amount and the volume were obtained by reducing a valve gauge height H1 of the engine specification comparing to H2 of a conventional valve 61 in contact with a conventional valve seat 43.
As shown in the table of
The engine 10 includes an intake valve 60 and an exhaust valve 70, and the height from the bottom surface 62 of the intake valve 60 and the exhaust valve 70 to the contact portion 64 in contact with the valve seat 42 may be 0.6 mm to 1.0 mm.
Also, the bottom surface 62 of the intake valve 60 and the exhaust valve 70 may be the flat shape.
In general, the bowl is formed at the valve, and the bowl is formed to reduce the weight of the valve.
However, the valve 60 and 70 applied to the engine 10 with the reduced cooling loss according to an exemplary embodiment of the present invention does not include the bowl, that is, is formed of the flat shape, reducing the combustion chamber area. For example, in the valve 61 of the conventional engine in
In an exemplary embodiment of the present invention, the volume 20 of the cylinder head is the space enclosed by the virtual flat surface X connecting the lower surface of the cylinder head 40 and by the cylinder head x, the distal end of the intake valve 60 when the intake valve 60 is closed and a distal end of an exhaust valve 70 mounted in the cylinder head 40 when the exhaust valve 70 is closed.
Referring to the table of
However, the engine with the reduced cooling loss according to an exemplary embodiment of the present invention is not specified to the numerical values shown in the table of
As shown in
As shown in
While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
For convenience in explanation and accurate definition in the appended claims, the terms “upper”, “lower”, “inner”, “outer”, “up”, “down”, “upper”, “lower”, “upwards”, “downwards”, “front”, “rear”, “back”, “inside”, “outside”, “inwardly”, “outwardly”, “internal”, “external”, “inner”, “outer”, “forwards”, and “backwards” 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 to explain certain principles of the invention and their practical application, to 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.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2017-0176206 | Dec 2017 | KR | national |
The present application is a Continuation-In-Part (CIP) of U.S. patent application Ser. No. 16/136,555, filed Sep. 20, 2018, which claims priority to Korean Patent Application No. 10-2017-0176206 filed on Dec. 20, 2017, the entire contents of which are incorporated herein for all purposes by these references.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16136555 | Sep 2018 | US |
| Child | 16842463 | US |
