Motorcycle secondary air compensating valve

Abstract

The invention discloses a motorcycle secondary air compensating valve which comprises a valve body provided with an air inlet cavity, an air outlet cavity and a negative pressure cavity. An air inlet pipe, an air outlet pipe and a negative pressure pipe are respectively arranged on the air inlet cavity, the air outlet cavity and the negative pressure cavity; a valve plate is arranged in the air inlet cavity; a reed valve is mounted in the air outlet cavity; a film is arranged in the negative pressure cavity; the valve plate and the film are mounted at the two ends of a valve rod; the valve rod can move in the axial direction under the action of air pressure; the air inlet cavity is communicated with the air outlet cavity via a communication cavity; the two ends of the communication cavity are respectively opened and closed by the valve plate and the reed valve; a through hole is formed in the first partition wall of the valve body, which is used for spacing the air inlet cavity and the communication cavity; the through hole can still communicate the air inlet cavity and the communication cavity when the communication cavity is closed by the valve plate. The motorcycle secondary air compensating valve can enable the valve plate to more quickly close the communication cavity, timely closes the reed valve, solves the problem that oil is accumulated in the valve body because of exhaust countercurrent of an engine, facilitates timely volatilization of liquid gas in the valve body and enlargement of air compensating flow, and improves exhaust emission.

Description

technical field [0001] The invention relates to a motorcycle secondary air supply valve, and specifically belongs to the technical field of motorcycle exhaust purification. Background technique [0002] Generally, domestic motorcycles generally use mechanical carburetors, which makes it difficult for the exhaust exhaust of motorcycles to meet the relevant national emission standards. For this reason, secondary air supply devices are generally used to reduce CO, HC, and NO X The amount of discharge, the fresh air is introduced into the cylinder head of the engine through the secondary air supply valve, the negative pressure pipe of the secondary air supply valve is connected with the intake port of the engine, and the intake pipe is connected with the air filter or other intake filter system , the outlet pipe is connected with the exhaust branch pipe of the engine, and the pulse negative pressure generated when the engine is exhausted is used to timely open or close the air i...

AI Technical Summary

Problems solved by technology

The valve body of the existing motorcycle secondary air supply valve is provided with an air intake chamber, an air outlet chamber and a negative pressure chamber, and an air inlet pipe, an air outlet pipe and a negative pressure pipe are respectively arranged on the air inlet chamber, the air outlet chamber and the negative pressure chamber , the air inlet and outlet chambers are connected by a communication chamber, and the two ends of the communication chamber are respectively opened and closed by a valve plate and a reed valve; when the engine intake end is under negative pressure, the valve plate in the air intake chamber goes up and connects with the intake pipe and the intake chamber, the fresh air passes through the intake pipe, the intake chamber and the communication chamber to the outlet chamber and enters the exhaust branch pipe; The valve body wall between them is attached to and cuts off the intake chamber and the communication chamber to stop supplying air to the engine exhaust pipe; when the vehicle is running at a non-uniform speed, the valve plate in the intake chamber will connect the intake chamber and the communication chamber Or the intake pipe is often cut off, but due to the hysteresis of the negative pressure chamber responding to the engine, the action of the valve plate is delayed, so that the separation between the intake chamber and the communication chamber is delayed, and a phase difference phenomenon occurs, such as figure 1 As shown, the curve A represents the negative pressure, the curve B is the theoretical air supply flow relative to the negative pressure, and the curve C is the actual air supply flow due to the hysteresis of the valve action, where △ρ is the flow caused by The phase difference; the existence of the phase difference makes the valve plate fail to cut off in time when it should cut off the intake cavity and the communication cavity or the intake pipe, so that fresh air continues to fill into the communication cavity, which will cause the reed valve (one-way valve) ) under the positive pressure of the exhaust end of the engine cannot be closed in time due to the entry of fresh air, the actuation sensitivity of the reed valve is affected, and at the same time, the reed valve cannot be closed in time under the positive pressure of the exhaust end of the engine The problem of backflow caused by engine exhaust and the problem of oil accumulation in the valve body caused by backflow are also not conducive to the timely volatilization of liquefied water accumulated in the valve body

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