Negative pressure supply device for engine

Abstract

Disclosed is a negative pressure supply device for an engine capable of simplifying the piping structure and improving the rigidity of the cylinder head. Assemble the vacuum pump (3) on the cylinder head (1), connect the suction port (15) connected with the pump suction port (27) of the vacuum pump (3) and the negative pressure outlet (17, The negative pressure passage (24) in the cylinder head of 18) is formed in the wall of the cylinder head (1), and the piping used to connect the negative pressure outlets (17, 18) and connect with the negative pressure passage (24) in the cylinder head The coupling portion (26) is arranged outside the wall portion of the cylinder head (1). In the case where two connecting holes (29) whose axes are perpendicular to one communicating passage (28) are formed opposite to each other, the ribs constituting the outer wall of the communicating passage (28) and the connecting hole (29) and the cylinder head (1 ) is continuously formed on the outer side of the wall portion, and the rigidity of the cylinder head (1) is improved.

Description

technical field [0001] The present invention relates to a negative pressure supply device for supplying negative pressure to a negative pressure working device used in a vehicle, and is particularly suitable for a negative pressure supply for an engine that supplies negative pressure to a negative pressure working device through a vacuum pump mounted on a cylinder head of an engine. device. Background technique [0002] Vacuum pumps have the function of generating negative pressure using rotational driving force, and the negative pressure is used in engine negative pressure operating equipment such as vacuum boosters for brakes and VSV (Vacuum Switching Valve: Vacuum Switching Valve) for turbocharger control. As a negative pressure supply device for an engine using such a vacuum pump, there is, for example, the negative pressure supply device described in Japanese Unexamined Patent Application Publication No. 2003-74411. In the negative pressure supply device of the engine,...

AI Technical Summary

Problems solved by technology

Such a vacuum pump is often assembled on the cylinder head, but in the negative pressure supply device of the engine described in Japanese Patent Application Laid-Open No. 2003-74411, although the negative pressure working equipment is arranged near the cylinder head, it still consists of pipes made of metal. The negative pressure forming passage member connects these negative pressure working equipment and the vacuum pump, so the piping structure is complicated, and the number of parts such as fixing pieces for fixing metal pipes is large.

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