CN2776779Y

CN2776779Y - Overfront load sensing valve

Info

Publication number: CN2776779Y
Application number: CN 200520080707
Authority: CN
Inventors: 王金山; 王峰; 刘波; 张勇
Original assignee: ZIBO LONGDA VEHICLE FITTINGS MANUFACTURING Co Ltd
Current assignee: ZIBO LONGDA VEHICLE FITTINGS MANUFACTURING Co Ltd
Priority date: 2005-02-26
Filing date: 2005-02-26
Publication date: 2006-05-03
Anticipated expiration: 2015-02-26

Abstract

The utility model provides a heading load sensing valve, which comprises a lower casing, an upper casing, lever cam mechanisms which are arranged in the casings, an air source sealing mechanism, a manipulating relay mechanism and pressure regulating mechanism, wherein the outer edge of a diaphragm in the manipulating relay mechanism is pressed and arranged between a piston and a guiding wheel, the inner edge of the diaphragm is embedded in a guiding wheel seat and the outer and the inner edges of the diaphragm are respectively formed into an E cavity and a D cavity with the upper end surface of the piston and the lower end surface of the guiding wheel seat. The utility model is characterized in that the piston adopts a two-stage piston, the diameter of the piston is reduced in a ladder way and the outer wall of the piston and the casings are formed into a vacuum preventing cavity G. The cavity wall of the vacuum preventing cavity G is provided with a vacuum preventing hole. On the basis of the original load sensing valve, the utility model causes the piston to be changed into the two-stage piston, the upper working end surface of the two-stage piston is larger than the lower working end surface of the two-stage piston, therefore the pressure ratio between a control cavity and an output cavity is enlarged. On the basis of the original output pressure force, the unequal output ratio is improved by 10% to 30%, therefore the braking safety for the drive is improved when an automobile is in zero load. The utility model has the advantages of good sensitivity, high braking force, short braking time and safe braking for the drive.

Description

Predominance sensing valve

Affiliated technical field

The utility model provides a kind of Predominance sensing valve, belongs to the automobile brake technical field.

Background technology

The load sensing valve principal feature is exactly the variation along with axle load, automatically regulates braking pressure, and the size that the makes braking force as far as possible adhesion condition between tire and ground adapts, with the stability that keeps automobile to brake under various load, various deceleration situation.But along with the increase of automobile tonnage, the lengthening of wheelbase, the braking force of being exported when existing load sensing valve is unloaded is low excessively, the braking time lag of back axle during heavy duty.Not ensure the service brake safety of large-tonnage, long wheelbase automobile.

The utility model content

The purpose of this utility model provides a kind ofly can overcome above-mentioned defective, automatically regulate the Predominance sensing valve of braking pressure, excellent working performance.Its technology contents is:

Comprise lower house, upper shell and the lever and cam mechanism that is installed in the housing, the source of the gas sealing mechanism, handle servo mechanism and pressure regulating device, wherein handle servo mechanism and comprise piston, diaphragm, guide wheel and wheel stand, and the outward flange of diaphragm is fitted between piston and the guide wheel, inner edges is inlaid in the wheel stand, diaphragm respectively with the upper surface of piston, the lower surface of wheel stand constitutes E chamber and D chamber, it is characterized in that: piston adopts two-diameter piston, the diameter ladder successively decreases, its outer wall upper shell sealing constitutes vacuum chamber prevention G, and the chamber wall of vacuum chamber prevention G is provided with anti-vacuum hole.

Described Predominance sensing valve, anti-vacuum hole are arranged on upper shell corresponding to vacuum chamber prevention G place.

Described Predominance sensing valve, piston adopts split type, comprise the relay piston and the charged piston that are superimposed, wherein the operative end surface of relay piston is greater than the operative end surface of charged piston, and the lower surface of wheel stand constitutes the E chamber, have anti-vacuum hole on the charged piston, anti-vacuum hole is communicated with the exhaust duct of valve.

Described Predominance sensing valve, lever and cam mechanism comprises lever, camshaft, cam, roller, push rod and push rod regulating spring, wherein lever is captiveed joint with cam, roller is positioned at the bottom of push rod and conflicts with the cam top, the upper end of push rod is set with the bottom that the push rod regulating spring is positioned at pressure regulating device, and it vertically is positioned at the central authorities of wheel stand.

Described Predominance sensing valve, the source of the gas sealing mechanism comprises valve spring, valve and valve seat, and wherein valve is positioned at the middle below of valve seat, and its upper surface and valve seat sealing are pressed with valve spring between the lower surface of valve and the lower house.

Described Predominance sensing valve, pressure regulating device comprises the wheel stand valve that is installed in successively from the bottom up in the housing, the wheel stand valve spring, spring perch, the pressure regulating valve spring, pressure regulating valve, relief piston, the relief piston spring, spring perch and relief piston seat, wherein the wheel stand valve is positioned at the top of push rod regulating spring, and be pressed with the wheel stand valve spring between the spring perch, the top of spring perch is equipped with pressure regulating valve and relief piston successively, and be pressed with the pressure regulating valve spring between spring perch and the pressure regulating valve, be pressed with the relief piston spring between relief piston and the spring perch, the top of spring perch is the relief piston seat.

Its principle of work is: load sensing valve is contained on the automobile chassis frame, links to each other with vehicle bridge by a lever and an elastomeric control arm.Under a certain size axle load, lever has definite position, promptly by the directly distortion of the suspension of reflection axle load size, the angle jerk value of decision lever.Unloaded glancing impact: the deflection of suspension is little, lever is not stressed, the position of camshaft, cam and push rod is in below, relief piston is opened pressure regulating valve under the relief piston acting force of the spring, the gap of crossing between pressure regulating valve and the relief piston from the next control Pneumatic pipe cleaner of main valve enters the D chamber, the promotion diaphragm moves with piston and opens valve, and bleed pressure is exported through delivery port.The rising of the control air pressure along with main valve has overcome relief piston when reaching certain numerical value spring force promotes to move on the relief piston, this moment pressure regulating valve under the combined action of control atmospheric pressure and pressure regulating valve spring force with the sealing surface sealing of wheel stand, the control air pressure that main valve is next enters the gas circuit of the top of diaphragm and shuts, how the control air pressure no matter main valve comes raises, and the output pressure of the delivery port of load sensing valve maintains control air pressure gas circuit and shuts in the preceding range of pressure.Constitute vacuum chamber prevention G because the piston structure that Predominance sensing valve adopts is two-diameter piston, its outer wall and housing seal, the last operative end surface of two-diameter piston is greater than following operative end surface; The perhaps dual-piston structure that adopts of Predominance sensing valve, relay piston promotes the charged piston motion, the operative end surface of relay piston is greater than the operative end surface of charged piston, its charged piston has anti-vacuum hole, anti-vacuum hole is communicated with the exhaust duct of valve, so just amplified the pressure ratio of control chamber and output cavity, on the basis of original output pressure power, improved not waiting of 10%-30% and export ratio, service brake safety when having improved the automobile zero load.Heavy duty glancing impact: along with the deflection increase of suspension, lever stress drive camshaft and cam promotion push rod are opened the wheel stand valve after moving up and compressing the push rod regulating spring, a control air pressure part of coming from main valve promotes diaphragm by the D chamber, top that the gap between pressure regulating valve and the relief piston enters diaphragm, the gap that another part Pneumatic pipe cleaner is crossed the wheel stand valve enters two-diameter piston upper surface E chamber and moves together and open valve, and bleed pressure is exported through delivery port.The rising of the control air pressure along with main valve has overcome relief piston when reaching certain numerical value spring force promotes to move on the relief piston, this moment, pressure regulating valve was under the combined action of control atmospheric pressure and pressure regulating valve spring force, and the control air pressure that main valve is come with the sealing surface sealing of wheel stand enters the gas circuit of the top of diaphragm and shuts.But another part enters the atmospheric pressure continuation promotion piston in E chamber and moves down till valve is all opened.Because the last operative end surface of two-diameter piston is greater than following operative end surface, the pressure ratio of so just having amplified control chamber and output cavity improves 15%-30% and does not wait the output ratio on the basis of original output pressure power.

The utility model compared with prior art, on the basis of original load sensing valve, change piston into two-diameter piston or dual-piston structure, the last operative end surface that makes piston is greater than following operative end surface, the pressure ratio of so just having amplified control chamber and output cavity, improving the output that do not wait of 10%-30% on the basis of original output pressure power compares, service brake safety when having improved the automobile zero load, sensitivity is good, the braking force height, can shorten braking time, ensure service brake safety.

Description of drawings

Fig. 1 is the structural representation of the utility model embodiment 1;

Fig. 2 is input, the output characteristic curve figure of the utility model embodiment 1

Fig. 3 is the structural representation of the utility model embodiment 2;

The specific embodiment

1, lower house 2, cam 3, roller 4, push rod 5, valve spring 6, valve 7, valve seat 8, piston 9, diaphragm 10, guide wheel 11, wheel stand 12, upper shell 13, push rod regulating spring 14, wheel stand valve 15, wheel stand valve spring 16, spring perch 17, pressure regulating valve 18, relief piston 19, relief piston spring 20, spring perch 21, relief piston seat 22, dust boot 23, lever 24, camshaft 25, anti-vacuum hole 26, pressure regulating valve spring 27, charged piston 28, relay piston

In Fig. 1: in the housing that lower house 1, upper shell 12 constitute lever and cam mechanism, source of the gas sealing mechanism are installed, handle servo mechanism and pressure regulating device, wherein lever and cam mechanism comprises lever 23, camshaft 24, cam 2, roller 3, push rod 4 and push rod regulating spring 13, wherein lever 23 is captiveed joint with cam 2, roller 3 is positioned at the bottom of push rod 4 and conflicts with cam 2 tops, the upper end of push rod 4 is set with the bottom that push rod regulating spring 13 is positioned at pressure regulating device, and it vertically is positioned at the central authorities of wheel stand 11; The source of the gas sealing mechanism comprises valve spring 5, valve 6 and valve seat 7, and wherein valve 6 is positioned at the middle below of valve seat 7, and its upper surface and valve seat 7 sealings are pressed with valve spring 5 between the lower surface of valve 6 and the lower house 1; Handle servo mechanism and comprise piston 8, diaphragm 9, guide wheel 10 and wheel stand 11, wherein the outward flange of diaphragm 9 is fitted between piston 8 and the guide wheel 10, inner edges is inlaid in the wheel stand 11, diaphragm 9 constitutes E chamber and D chamber with the upper surface of piston 8, the lower surface of wheel stand 11 respectively, piston 8 adopts two-diameter piston, the diameter ladder successively decreases, its outer wall upper shell 12 sealings constitute vacuum chamber prevention G, upper shell 12 is provided with anti-vacuum hole 25 corresponding to vacuum chamber prevention G place, and the last operative end surface that makes piston 8 is greater than following operative end surface; Pressure regulating device comprises the wheel stand valve 14 that is installed in successively from the bottom up in the housing, wheel stand valve spring 15, spring perch 16, pressure regulating valve spring 26, pressure regulating valve 17, relief piston 18, relief piston spring 19, spring perch 20 and relief piston seat 21, wherein wheel stand valve 14 is positioned at the top of push rod regulating spring 13, and be pressed with wheel stand valve spring 15 between the spring perch 16, the top of spring perch 16 is equipped with pressure regulating valve assembly 17 and relief piston 18 successively, wherein be pressed with pressure regulating valve spring 26 between pressure regulating valve 17 and the spring perch 16, be pressed with relief piston spring 19 between relief piston 18 and the spring perch 20, the top of spring perch 20 is relief piston seats 21.

In Fig. 2: curve 29 be unloaded, in input one output static characteristics variable range curve when carrying, input-output static characteristics variable range curve when curve 29 be heavily loaded.

Embodiment 2 shown in Figure 3 is substantially with embodiment 1, just piston 8 adopts split type, comprise the relay piston 28 and the charged piston 27 that are superimposed, wherein the operative end surface of relay piston 28 is greater than the operative end surface of charged piston 27, and the lower surface of wheel stand 11 constitutes the E chamber, have anti-vacuum hole 25 on the charged piston 27, anti-vacuum hole 25 is communicated with the exhaust duct of valve 6.

Claims

1, a kind of Predominance sensing valve, comprise lower house (1), upper shell (12) and be installed in lever and cam mechanism in the housing, the source of the gas sealing mechanism, handle servo mechanism and pressure regulating device, that wherein handles servo mechanism comprises piston (8), diaphragm (9), guide wheel (10) and wheel stand (11), and the outward flange of diaphragm (9) is fitted between piston (8) and the guide wheel (10), inner edges is inlaid in the wheel stand (11), diaphragm (9) respectively with the upper surface of piston (8), the lower surface of wheel stand (11) constitutes E chamber and D chamber, it is characterized in that: piston (8) adopts two-diameter piston, the diameter ladder successively decreases, its outer wall upper shell (12) sealing constitutes vacuum chamber prevention G, and the chamber wall of vacuum chamber prevention G is provided with anti-vacuum hole (25).

2, Predominance sensing valve as claimed in claim 1 is characterized in that: anti-vacuum hole (25) is arranged on upper shell (12) corresponding to vacuum chamber prevention G place.

3, Predominance sensing valve as claimed in claim 1, it is characterized in that: piston (8) adopts split type, comprise the relay piston (28) and the charged piston (27) that are superimposed, wherein the operative end surface of relay piston (28) is greater than the operative end surface of charged piston (27), and the lower surface of wheel stand (11) constitutes the E chamber, have anti-vacuum hole (25) on the charged piston (27), anti-vacuum hole (25) is communicated with the exhaust duct of valve (6).

4, Predominance sensing valve as claimed in claim 1, it is characterized in that: lever and cam mechanism comprises lever (23), camshaft (24), cam (2), roller (3), push rod (4) and push rod regulating spring (13), wherein lever (23) is captiveed joint with cam (2), roller (3) is positioned at the bottom of push rod (4) and conflicts with cam (2) top, the upper end of push rod (4) is set with the bottom that push rod regulating spring (13) is positioned at pressure regulating device, and it vertically is positioned at the central authorities of wheel stand (11).

5, Predominance sensing valve as claimed in claim 1, it is characterized in that: the source of the gas sealing mechanism comprises valve spring (5), valve (6) and valve seat (7), wherein valve (6) is positioned at the middle below of valve seat (7), its upper surface and valve seat (7) sealing is pressed with valve spring (5) between the lower surface of valve (6) and the lower house (1).

6, Predominance sensing valve as claimed in claim 1, it is characterized in that: pressure regulating device comprises the wheel stand valve (14) that is installed in successively from the bottom up in the housing, wheel stand valve spring (15), spring perch (16), pressure regulating valve spring (26), pressure regulating valve (17), relief piston (18), relief piston spring (19), spring perch (20) and relief piston seat (21), wherein wheel stand valve (14) is positioned at the top of push rod regulating spring (13), and be pressed with wheel stand valve spring (15) between the spring perch (16), the top of spring perch (16) is equipped with pressure regulating valve assembly (17) and relief piston (18) successively, wherein be pressed with pressure regulating valve spring (26) between pressure regulating valve (17) and the spring perch (16), be pressed with relief piston spring (19) between relief piston (18) and the spring perch (20), the top of spring perch (20) is relief piston seat (21).