JP3382711B2 - DOHC internal combustion engine with exhaust turbocharger - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust turbocharger,
The present invention relates to a DOHC-type internal combustion engine mounted on one longitudinal side surface. 2. Description of the Related Art In general,
When an exhaust turbocharger is installed in an internal combustion engine, for example, as described in Japanese Utility Model Laid-Open No. 57-8321, a blower compressor in the exhaust turbocharger is used to transfer the internal combustion engine. And a bypass line for the blower compressor is provided between the supercharging line of the compressor and the air suction line from the air cleaner to the blower compressor. In the bypass line, the intake pressure downstream of the throttle valve is provided. And a bypass valve that opens and closes is provided in connection with the configuration to prevent the supercharging pressure from excessively increasing. That is, in an internal combustion engine with an exhaust turbocharger, the size of the entire internal combustion engine including the exhaust turbocharger is reduced due to the need for the bypass valve for supercharging control as described above. However, there is a problem that the size is increased by the provision of the bypass valve. The present invention relates to D
In the OHC type internal combustion engine, paying attention to the fact that the lateral width of the internal combustion engine is wide at one end portion in order to provide a timing chain or a timing belt for both cam shafts, utilizing this fact, It is a technical task to solve the above problem. [0004] In order to achieve the above technical object, the present invention provides a method in which a timing chain or a timing belt for both camshafts is provided at one end in the cylinder row direction, In a DOHC type internal combustion engine in which an exhaust turbocharger is disposed on one of the two longitudinal side surfaces parallel to each other, between a wide portion at one end of the internal combustion engine and the exhaust turbocharger. Is provided with a bypass valve for the blower compressor in the exhaust turbocharger. " [0005] In the DOHC type internal combustion engine,
Since the lateral width of the internal combustion engine is wide at one end in order to provide a timing chain or a timing belt for both camshafts, one of the left and right longitudinal side surfaces of the DOHC type internal combustion engine is one of the longitudinal sides. When an exhaust turbocharger is mounted on the side surface, a dead space is inevitably formed in a portion between the exhaust turbocharger and a wide portion at one end of the internal combustion engine. Therefore, a bypass valve for the blower compressor in the exhaust turbocharger is provided at a portion between the exhaust turbocharger and a wide portion at one end of the internal combustion engine. Dead space,
It can be effectively used for disposing a bypass valve. Thus, according to the present invention, DOHC with exhaust turbocharger
This has the effect of avoiding an increase in the size of the internal combustion engine. An embodiment of the present invention will be described below with reference to the drawings. In the drawing, reference numeral 1 denotes a DOHC-type internal combustion engine. One end of the internal combustion engine 1 in the cylinder row direction is formed in a wide portion 1a. A timing chain 4 or a timing belt for 3 is provided. In the internal combustion engine 1, an exhaust manifold 5 is provided on one of the left and right longitudinal sides parallel to the cylinder row direction, and a throttle body 7 with a throttle valve is provided on the other longitudinal side at an inlet end. Each of the intake manifolds 6 is mounted. Reference numeral 8 denotes an exhaust turbocharger including an exhaust turbine 9 and a blower compressor 10. The exhaust turbocharger 8 is attached to a portion outside the exhaust manifold 5. 8, the blower compressor 10 is disposed so as to face the wide portion 1a of the internal combustion engine 1, and the inlet of the exhaust turbine 9 is connected to the exhaust manifold 5, while the suction port to the blower compressor 10 is An air suction line 11 from an air cleaner (not shown) is connected to a discharge port from the blower compressor 10 and a supercharging line 12 to the throttle body 7 in the intake manifold 7. Reference numeral 13 denotes a bypass valve. As shown in FIG. 2, the bypass valve 13 has a valve body 13c mounted on a diaphragm 13b and a valve body 13c seated in a valve box 13a. A valve seat opening 13d,
A spring 13e for urging the valve 13c against a valve seat 13d, a pressure chamber 13f partitioned by the diaphragm 13b, and the valve 13c and the valve seat 13d in the valve box 13a. And a valve chamber 13g formed so as to surround it. The bypass valve 13 is disposed at a position between the wide portion 1a at one end of the internal combustion engine 1 and the blower compressor 10 of the exhaust turbocharger 8, and a valve chamber thereof is provided. A first bypass pipe 15 branched from the supercharging pipe 12 is connected to a first socket pipe 14 communicating with 13g, and the air suction pipe is connected to a second socket pipe 16 communicating with the valve seat 13d. A second bypass line 17 is connected to the passage 11, and the intake pressure in the intake manifold 7 is introduced into the pressure chamber 13 f via an intake pressure transmission line 18. When the pressure decreases, the valve body 13c opens against the spring 13e due to the pressure difference from the supercharging pressure in the supercharging line 12, and a part of the supercharging air in the supercharging line 12 is removed by both bypasses. Conduit 15, The through 7 air intake conduit 11
By controlling the supercharging pressure, the supercharging pressure in the supercharging line 12 is controlled so as not to rise any more. The bypass valve 13 has a third socket pipe 19 communicating with the second socket pipe 16, and the third socket pipe 19 is provided with a ventilation from a valve mechanism chamber of the internal combustion engine 1. The pipe 20 is connected so that blow-by gas or the like in the valve mechanism chamber is always sucked into the blower compressor 10. As described above, by disposing the bypass valve 13 at a position between the exhaust turbocharger 8 and the wide portion 1a at one end of the internal combustion engine 1, the bypass valve 13 is connected to the exhaust turbocharger 8. Since the dead space inevitably formed between the internal combustion engine 1 and the wide portion 1a can be effectively used for disposing the bypass valve 13, the size of the DOHC type internal combustion engine with the exhaust turbocharger is increased. Can be avoided. As in the above embodiment, the bypass valve 13 is provided with a third socket pipe 19 communicating with the second socket pipe 16, and the third socket pipe 19 is provided with a valve operating mechanism in the internal combustion engine 1. By connecting the ventilation pipe 20 from the chamber, the ventilation in the valve mechanism chamber can be performed simultaneously via the second bypass pipe 17, so that the ventilation in the valve mechanism chamber is performed. There is an advantage that the structure in such a case can be simplified. The bypass pipes 15 and 17 and the ventilation pipe 20 are all hoses made of a soft elastic material such as rubber, and are configured to support the bypass valve 13 by these. In addition, the bypass valve 13 is not configured to be mounted on the internal combustion engine 1 or the like, and the mounting structure is simplified.

[Brief description of the drawings] FIG. 1 is a plan view showing an embodiment of the present invention. FIG. 2 is a vertical sectional front view of a bypass valve. [Explanation of symbols] 1 Internal combustion engine 1a Wide part of internal combustion engine 2,3 camshaft 4 Timing chain 5 Exhaust manifold 6 Intake manifold 7 Throttle body 8 Exhaust turbocharger 9 Exhaust turbine 10 Blower compressor 11 Air intake line 12 Supercharging pipeline 13 Bypass valve 15, 17 Bypass line

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F02B 37/16 F02B 67/00

Claims (1)

(57) Claims 1. A timing chain or a timing belt for both camshafts is provided at one end in the cylinder row direction.
In a DOHC type internal combustion engine having an exhaust turbocharger disposed on one of the two longitudinal side surfaces parallel to the cylinder row direction, a wide portion at one end of the internal combustion engine;
A bypass valve for a blower compressor in the exhaust turbocharger is disposed at a portion between the exhaust turbocharger and the DO with an exhaust turbocharger.
HC type internal combustion engine.