Intake system for engine

Abstract

Output performance of the engine may be maximized by a configuration in which air is supplied so as to maximize volumetric efficiency of the respective cylinders in a multi-cylinder engine including a plurality of cylinders.

Claims

1. An intake system for an engine, comprising: a throttle body; at least two primary branch pipes extending from the throttle body; and a plurality of secondary branch pipes extending from respective primary branch pipes into at least two of a plurality of cylinders configuring one engine, wherein the primary branch pipes are provided with separate second chambers accommodating air in order to form an entire volume of the primary branch pipes, wherein the primary branch pipes are spirally twisted from a rear end of the throttle body and have the second chambers positioned at the center of a spiral portion of the primary branch pipes, and wherein the second chambers are formed in a vessel shape in which each of semi-circular predetermined cross section shapes thereof is lengthily extended along a spiral central axis of the primary branch pipes to form one cylindrical appearance.

2. The intake system of claim 1, wherein a first chamber accommodating air in a predetermined volume thereof is provided between a throttle valve of the throttle body and the primary branch pipes; and the primary branch pipes have an entire volume at least larger than stroke volumes of the respective cylinders.

3. The intake system of claim 1, wherein the second chambers have a space in which a cross section is expanded and then contracted on the primary branch pipes.

4. The intake system of claim 1, wherein the second chambers have a space connected to the middle of the primary branch pipes through a separate connection neck.

5. The intake system of claim 2, wherein each of the volume of the first chamber and the entire volume of the primary branch pipes is more than two times than the stroke volumes of the respective cylinders.

6. The intake system of claim 5, wherein the secondary branch pipes branched from one primary branch pipe of the primary branch pipes are connected to cylinders having ignition times different from those of other cylinders among a series of ignition times, respectively.

7. The intake system of claim 6, wherein the engine is an inline 4 cylinder engine including first to fourth cylinders sequentially disposed in a row; two primary branch pipes are branched from the throttle body; the secondary branch pipes are branched in pairs from each of the primary branch pipes; two secondary branch pipes branched from a first primary branch pipe of the two primary branch pipes are connected to second and third cylinders, respectively; and two secondary branch pipes branched from a second primary branch pipe of the two primary branch pipes are connected to first and fourth cylinders, respectively.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a conceptual diagram showing an exemplary intake system for an engine according to the present invention;

(2) FIG. 2 is a conceptual diagram showing an exemplary intake system for an engine according to the present invention;

(3) FIG. 3 is a perspective view showing an exemplary intake system for an engine according to the present invention;

(4) FIG. 4 is a diagram viewed from the left of FIGS. 3; and

(5) FIG. 5 is a graph of a torque depending on an engine speed in which an effect of the present invention is compared with the related art.

DETAILED DESCRIPTION

(6) 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 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.

(7) Referring to FIGS. 1 and 2, each of the intake systems for an engine according to various embodiments of the present invention is configured to include a throttle body 1; at least two primary branch pipes 3 branched from the throttle body 1; and a plurality of secondary branch pipes 7 branched from the primary branch pipes 3 into at least two of a plurality of cylinders 5 configuring one engine.

(8) That is, the throttle body 1 is configured to receive air introduced from the atmosphere through at least one pipe, control the entire amount of air sucked into the engine through a throttle valve 9, and supply the air to the respective cylinders 5 by a sequential branch structure of the primary and secondary branch pipes 3 and 7 disposed at a rear end thereof.

(9) A first chamber 11 accommodating air in a predetermined volume thereof is provided between the throttle valve 9 of the throttle body 1 and the primary branch pipe 3, and the primary branch pipes 3 may have the entire volume at least larger than stroke volumes of the respective cylinders 5.

(10) In various embodiments and as shown in FIGS. 1 and 2, the primary branch pipes 3 are further provided with separate second chambers 13 accommodating air on the pipe in order to form the entire volume of the primary branch pipes 3.

(11) The primary branch pipes 3 may also be configured so that the entire volume of the primary branch pipes themselves is larger than the stroke volumes of the respective cylinders, without separately including the second chambers 13.

(12) In various embodiments as shown in FIG. 1, the second chamber 13 has a form of a space in which a cross section of a pipe is expanded and then contracted on a pipe of the primary branch pipe 3, and in various embodiments as shown in FIG. 2, the second chamber 13 has a form of a space connected to the middle of a pipe of the primary branch pipe 3 through a separate connection neck 19.

(13) Here, each of the volume of the first chamber 11 and the entire volume of the primary branch pipes 3 may be more than two times than the stroke volumes of respective cylinders 5.

(14) That is, in order to always smoothly satisfy air amounts required in the respective cylinders 5, each of the volume of the first chamber 11 and the entire volume of the primary branch pipes 3 should be more than two times than the stroke volumes of the respective cylinders 5. In this case, sufficient volumetric efficiency is secured in the respective cylinders 5, thereby making it possible to improve an output of the engine.

(15) FIG. 5 shows experimental data indicating that the engine using the intake system according to various embodiments of the present invention to which the restriction of the volume of the first chamber 11 and the entire volume of the primary branch pipes 3 as described above is applied has output characteristics improved as compared with a general engine according to the related art that does not use the intake system according to various embodiments of the present invention and an engine in which a 4-2-1 type of outtake manifold is used only in an outtake system. Particularly, it could be appreciated from FIG. 5 that the present invention represents significant output improvement in low speed and medium speed regions of the engine as compared with the related art.

(16) Meanwhile, the secondary branch pipes 7 branched from one primary branch pipe 3 may be connected to cylinders 5 having ignition times different from those of other cylinders 5 among a series of ignition times, respectively, to prevent intake interference between the respective cylinders 5 from being generated.

(17) That is, in the case in which the engine is an inline 4 cylinder engine including first to fourth cylinders 5 sequentially disposed in a row as shown in FIG. 1 or FIG. 2, two primary branch pipes 3 are branched from the throttle body 1, the secondary branch pipes 7 are branched in pairs from each of the primary branch pipes 3, two secondary branch pipes 7 branched from one of the two primary branch pipes 3 are connected to the second and third cylinders 5, respectively, and two secondary branch pipes 7 branched from the other of the two primary branch pipes 3 are connected to the first and fourth cylinders 5, respectively.

(18) In this case, since the engine is ignited in a sequence of the first cylinder-the third cylinder-the fourth cylinder-the second cylinder, the respective cylinders 5 connected to the secondary branch pipes 7 as described above substantially independently receive air from the throttle body 1 in a state in which the respective cylinders are isolated from the cylinders 5 having ignition times adjacent to those of the respective cylinders by the secondary branch pipes 7 and the primary branch pipes 3, thereby preventing deterioration of volumetric efficiency due to intake interference.

(19) FIGS. 3 and 4 three-dimensionally show the intake system according to various embodiments of the present invention. The intake system according to various embodiments of the present invention has a structure in which the primary branch pipes 3 are spirally twisted from a rear end of the throttle body 1 and have the second chambers 13 positioned at the center of a spiral portion and the secondary branch pipes 7 are disposed in a state in which end portions thereof connected to the cylinders 5 are opened on a straight line.

(20) Here, the second chambers 13 may have a vessel shape in which a predetermined cross section shape is lengthily extended along a spiral central axis formed by the primary branch pipes 3.

(21) Particularly, in various embodiments, the second chambers 13 are formed of vessels in which each of the semi-circular predetermined cross section shapes is lengthily extended along the spiral central axis formed by the primary branch pipes 3 to form one cylindrical appearance, thereby making it possible to make the intake system compact and secure a volume of the second chambers 13 enough to secure volumetric efficiency of the respective cylinders 5.

(22) Although the second chambers 13 has the cylindrical appearance by disposing vessels separated from each other and having two semi-circular cross sections as shown to be adjacent to each other, the second chambers 13 may be formed in an integral cylindrical shape in which the two vessels are formed integrally with each other and a partition wall isolating the two vessels from each other is formed at the center. One will appreciate that such integral components may be monolithically formed.

(23) According to various embodiments of the present invention, it is possible to maximize output performance of the engine by a configuration in which air is supplied so as to maximize volumetric efficiency of the respective cylinders in a multi-cylinder engine including a plurality of cylinders.

(24) For convenience in explanation and accurate definition in the appended claims, the terms rear, left, and etc. are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures.

(25) 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.