CN-116717601-B - Double-valve-controlled PRV valve

CN116717601BCN 116717601 BCN116717601 BCN 116717601BCN-116717601-B

Abstract

The invention relates to the technical field of automobile accessories and provides a double-valve controlled PRV (pressure relief valve) which comprises a valve seat, a piston, a diaphragm, a spring, a sealing piece and a sealing piece, wherein an air inlet cavity and an air outlet cavity are arranged in the valve seat, an accommodating cavity with one end communicated with outside air is formed at the intersection of the air inlet cavity and the air outlet cavity, the piston is movably inserted in the accommodating cavity, an air outlet hole penetrating through a first part and a second part is formed in the middle of the piston, the diaphragm is movably connected to the upper end of the piston, the spring is sleeved on the outer side wall of the piston, and the end part of the spring is movably abutted against one side of the diaphragm, which faces to the movement. Compared with the prior art, the invention has the advantages that the sealing element for sealing the piston and the cavity is arranged in the valve seat, when the negative pressure in the cavity is large, the sealing element and the diaphragm jointly realize the sealing of the air inlet cavity and the air outlet cavity, so that the sealing function is easier to realize under the condition of the same working condition, the crankcase negative pressure is prevented from being too low, and the normal starting of the engine is ensured.

Inventors

FANG LIFENG
RAO CONGCHAO
MAO JINXIN
HUANG GAI

Assignees

神通科技集团股份有限公司

Dates

Publication Date: 20260505
Application Date: 20230625

Claims (4)

1. A dual valve controlled PRV valve, comprising: the valve seat is internally provided with an air inlet cavity and an air outlet cavity, an accommodating cavity with one end communicated with outside air is formed at the intersection of the air inlet cavity and the air outlet cavity, and the accommodating cavity is provided with a large end communicated with the air inlet cavity and a small end communicated with the air outlet cavity; The piston is movably inserted into the containing cavity, the piston is provided with a first part movably arranged at the large end of the containing cavity and a second part movably inserted into the small end of the containing cavity, and the middle position of the piston is provided with an air outlet hole penetrating through the first part and the second part; The diaphragm is movably connected to the upper end of the piston and seals the containing cavity and the outside air, and the diaphragm can enable the air outlet hole to be closed because negative pressure is communicated in the containing cavity and abuts against the piston; the spring is sleeved on the outer side wall of the piston, and the end part of the spring is movably abutted against one side of the diaphragm, which faces the movement; The sealing piece is arranged in the containing cavity, can form sealing between the piston and the containing cavity due to extrusion of the piston, and can isolate the air inlet cavity from the air outlet cavity together with the diaphragm; The sealing piece comprises a sealing ring which is sleeved on the outer side wall of the second part of the piston and movably abuts against the end part of the first part of the piston, a valve core, a mounting surface is arranged at one end of the small end of the containing cavity, which faces the air outlet cavity, and one end of the valve core is movably inserted on the mounting surface, and the upper end of the valve core movably abuts against the lower end of the piston.
2. The dual valve controlled PRV valve of claim 1 wherein a plurality of through slots are provided in a sidewall of said first portion of said piston in communication with said outlet port.
3. The dual valve controlled PRV valve of claim 1 wherein a plurality of stop bumps are formed on a sidewall of said chamber around a circumference of said piston, a plurality of said stop bumps being disposed around said spring to prevent said spring from tilting.
4. The dual valve controlled PRV valve of claim 1 wherein a mount is provided at an end of said valve element remote from said piston, said mounting surface being provided with a mounting hole, said mounting hole being expandable by insertion of said mount for passage of said mount and resiliently returning by spanning of said mount to prevent disengagement of said valve element from said mounting surface when said mount is snapped into said mounting hole.

Description

Double-valve-controlled PRV valve Technical Field The invention relates to the technical field of automobile accessories, in particular to a double-valve controlled PRV valve. Background The crankcase is the most important component of the engine, the cavity structure for receiving the crankshaft of the automobile, and for a common engine, is located just below the engine. The crankshaft is a shaft with a crank, and rotates around an axle center when the engine works, and is connected with the connecting rod, and the reciprocating motion of the piston is converted into the rotation of the crankshaft through the action of the connecting rod, so that the vehicle is driven. The crankcase is provided with a PRV valve (crankcase pressure reducing regulating valve) integrated with the crankcase, the PRV valve is used for reducing the internal pressure of the crankcase, and the gas exhausted from the crankcase is introduced into a ventilating duct through the PRV valve and finally enters the air inlet pipe. The PRV valve on the engine is used for pressure relief, and when the pressure in the equipment or the pipeline exceeds the set pressure of the pressure relief valve, the pressure relief is automatically opened, so that the medium pressure in the equipment and the pipeline is ensured to be under the set pressure, the equipment and the pipeline are protected, and accidents are prevented. The traditional PRV valve generally comprises a PRV valve cover, a PRV diaphragm, a linear spring, a valve seat and other parts, the working principle is that the upper part of the PRV diaphragm is communicated with the outside through a cavity in front of the PRV valve cover, the air pressure is atmospheric pressure, the vacuum degree at the lower part of the PRV diaphragm, particularly at an air outlet hole, is changed along with the change of the load of an engine, when the vacuum degree at the air outlet hole is high, the pressure difference between the upper side and the lower side of the PRV diaphragm is increased, the PRV diaphragm is pushed to move towards the air outlet hole, in order to avoid the air outlet hole from being completely blocked by the PRV diaphragm, a compression spring is usually arranged between the PRV diaphragm and the air outlet hole, the compression spring is the linear spring, when an automobile is started, the lower load outlet of the PRV valve generates larger negative pressure, the larger reverse elasticity generated by the linear spring is larger when the pressure generated by the inlet positive pressure and the linear spring is equal to the negative pressure value of the lower load outlet of the PRV valve, when the PRV valve is in a dynamic balance state, the internal negative pressure is not closed, the engine power is reduced, the consumption of the fuel and engine oil is increased, and the starting is difficult. Disclosure of Invention The invention aims to solve the technical problem of the prior art and provides a double-valve controlled PRV valve for preventing the negative pressure in a crankcase from being too low. The invention solves the technical problems by providing a double-valve controlled PRV valve, which comprises a valve seat, a valve seat and a valve seat, wherein an air inlet cavity and an air outlet cavity are arranged in the valve seat, a containing cavity with one end communicated with outside air is formed at the intersection of the air inlet cavity and the air outlet cavity, and the containing cavity is provided with a large end communicated with the air inlet cavity and a small end communicated with the air outlet cavity; The piston is movably inserted into the containing cavity, the piston is provided with a first part movably arranged at the large end of the containing cavity and a second part movably inserted into the small end of the containing cavity, and the middle position of the piston is provided with an air outlet hole penetrating through the first part and the second part; The diaphragm is movably connected to the upper end of the piston and seals the containing cavity and the outside air, and the diaphragm can enable the air outlet hole to be closed because negative pressure is communicated in the containing cavity and abuts against the piston; the spring is sleeved on the outer side wall of the piston, and the end part of the spring is movably abutted against one side of the diaphragm, which faces the movement; the sealing piece is arranged in the containing cavity, and can form sealing between the piston and the containing cavity due to extrusion of the piston, and the sealing piece and the diaphragm jointly isolate the air inlet cavity from the air outlet cavity. In the above-described dual valve controlled PRV valve, the seal comprises: The sealing ring is sleeved on the outer side wall of the second part of the piston and movably abuts against the end part of the first part of the piston; the valve core is arranged at one end of the small end of the c