Two-stage and three-stage snub brake main valve provided with filter screen for Dongfeng 140

Abstract

The invention discloses a two-stage and three-stage snub brake main valve provided with a filter screen for Dongfeng 140. The snub brake main valve comprises an upper body, a lower body, a tappet rod, a tappet rod seat, a piston and a valve, wherein a balance piston sleeves the upper part of an inner cavity of the upper body; a first stage balance spring sleeves the outer part of a spring clamp sleeve, and a second stage balance spring sleeves the inner part of the spring clamp sleeve; an upper valve seat is clamped and fixed at the inner side of the wall of an upper valve by an elastic check ring, and a lower valve seat is clamped and fixed at the inner side of the wall of a lower valve by another elastic check ring. The structure of an upper part ring-shaped inner flanging and a lower part ring-shaped outer flanging is adopted by the snub brake main valve, so that the structure of the spring clamp sleeve is simplified, the processing difficulty and the assembly difficulty are reduced, and the yield of products can be greatly improved. The filter screen of a valve core is simple in structure and convenient to install, and can be arranged outside the valve core of a brake valve, especially, the valve core of the brake main valve; the filter screen is directly arranged around the valve core, a solid shell carried in gas can be prevented from entering the valve core, so that the work reliability of the valve core is greatly improved; therefore, the brake accidents can be avoided.

Description

technical field [0001] The invention relates to the technical field of parts and components of automobile brake valves, in particular to a two-stage and three-stage spot brake master valve with a filter screen for Dongfeng 140. Background technique [0002] The braking system of trucks and heavy-duty vehicles in the prior art brakes too quickly, and the foot feel is not easy to control, which will easily cause the brake pads to heat up rapidly, resulting in carbonization, which directly affects the braking effect. bias, affecting the overall stability, resulting in insecurity, or unnecessary economic losses. In order to solve these braking problems of trucks, our unit has successively proposed a series of patents on the two-stage brake master valve and the three-stage balance piston assembly, such as the invention patent with the publication number CN 101837774 A, which can output "secondary point brake". The principle of "point brake" can make the compressed air form puls...

AI Technical Summary

Problems solved by technology

[0003] At present, there are generally filters in the pipeline of the braking system, which are used to filter the solid particle impurities flowing with the gas in the air pipe, so as to ensure that each braking component is not affected by solid particle impurities and ensure the reliability of its work. However, due to the distance between the filter and the spool of each valve, it cannot be avoided that the filtered gas will be polluted by other newly generated solid particles before entering the spool. Sometimes solid particles will still enter the spool and affect the spool. The airtightness caused by air leakage accidents, a new solution needs to be put forward

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