阅读说明：本技术 用于弹簧制动气室的模块化呼吸阀及一种弹簧制动气室 (Modular breather valve for spring brake chamber and spring brake chamber ) 是由 屠志良 李大刚 彭孟男 于 2021-08-23 设计创作，主要内容包括：本发明公开了用于弹簧制动气室的模块化呼吸阀及一种弹簧制动气室,其中呼吸阀包括端盖主体、阀芯、导套以及平衡弹簧,端盖主体固定设置于活塞推杆的顶部,导套固定设置于端盖主体内,阀芯活动设置于导套内；导套底部设有中心呼吸孔,阀芯靠近密封平面的一端设有密封唇口；活塞推杆的侧壁开设有推杆侧壁孔；阀芯的外侧壁与导套的内侧壁间隙配合,配合间隙面积分别与中心呼吸孔的通气截面积和推杆侧壁孔的通气截面积相当。本发明设计结构简单,内呼吸阀结构所需内部体积有明显缩减,有利于活塞式弹簧制动气室驻车腔的轻量化设计,且本发明中阀门密封不需要长期暴露在行车腔工作气压下,内呼吸阀的密封可靠性更稳定优秀。(The invention discloses a modularized breather valve for a spring brake air chamber and the spring brake air chamber, wherein the breather valve comprises an end cover main body, a valve core, a guide sleeve and a balance spring, the end cover main body is fixedly arranged at the top of a piston push rod, the guide sleeve is fixedly arranged in the end cover main body, and the valve core is movably arranged in the guide sleeve; the bottom of the guide sleeve is provided with a central breathing hole, and one end of the valve core close to the sealing plane is provided with a sealing lip; a push rod side wall hole is formed in the side wall of the piston push rod; the outer side wall of the valve core is in clearance fit with the inner side wall of the guide sleeve, and the area of the fit clearance is respectively equal to the ventilation sectional area of the central breathing hole and the ventilation sectional area of the side wall hole of the push rod. The design structure of the invention is simple, the internal volume required by the internal breather valve structure is obviously reduced, the lightweight design of the piston type spring brake air chamber parking cavity is facilitated, the valve seal in the invention does not need to be exposed under the working air pressure of the driving cavity for a long time, and the sealing reliability of the internal breather valve is more stable and excellent.)

1. The modularized breather valve is characterized by comprising an end cover main body, a valve core, a guide sleeve and a balance spring, wherein the end cover main body is fixedly arranged at the top of the piston push rod, the guide sleeve is fixedly arranged in the end cover main body, the valve core is movably arranged in the guide sleeve, and the balance spring is arranged between the valve core and the guide sleeve;

a central breathing hole is formed in the sealing plane at the bottom of the guide sleeve and is communicated with a ventilation channel of the piston push rod; one end of the valve core close to the sealing plane is provided with a sealing lip corresponding to the central breathing hole;

a push rod side wall hole is formed in the side wall of the piston push rod and communicated with the inner cavity of the guide sleeve; the outer side wall of the valve core is in clearance fit with the inner side wall of the guide sleeve, and the area of the fit clearance is respectively equal to the ventilation sectional area of the central breathing hole and the ventilation sectional area of the side wall hole of the push rod.

2. The modular breather valve for a spring brake chamber of claim 1, wherein the opposing upper outer sidewall of the guide sleeve and the top end of the guide sleeve are in clearance fit with the inner sidewall and the inner top wall of the end cap body, respectively, the fit clearance area being comparable to the cross-sectional ventilation area of the pushrod sidewall aperture.

3. The modular breather valve for a spring brake chamber of claim 2, wherein the back side of the poppet and/or the inner top wall of the end cap body is provided with a protrusion such that the back side of the poppet and the inner top wall of the end cap body are spaced apart from each other.

4. The modular breather valve for a spring brake chamber as claimed in claim 1, wherein the valve core is provided with a spring groove inwardly formed in the middle of the sealing lip, the opposite upper portion of the central breather hole is provided with a stepped hole having a sectional area larger than that of the central breather hole, and both ends of the balance spring are respectively abutted against the spring groove and a step of the stepped hole.

5. The modular breather valve for a spring brake chamber of claim 1, wherein the end cap body has an interference fit with a top portion of the piston push rod.

6. The modular breather valve for a spring brake chamber according to claim 5, wherein sealing rings are respectively arranged between the end cover main body and the piston push rod at the upper side and the lower side of the side wall hole of the push rod; and a sealing ring is arranged between the outer side face of the lower part of the guide sleeve and the inner side face of the end cover main body.

7. The modular breather valve for a spring brake chamber of claim 1, wherein the end cap body is integrally formed with the piston push rod.

8. The modular breather valve for a spring brake chamber of claim 1, wherein the guide sleeve is fixedly disposed within the end cap body via a stop.

9. A spring brake air chamber is characterized by comprising the modular breather valve for the spring brake air chamber, which is disclosed by any one of claims 1 to 8, and further comprising a parking chamber, a traveling chamber and an air chamber middle body positioned between the parking chamber and the traveling chamber, wherein a piston is arranged in the parking chamber and divides the parking chamber into a parking cavity and a parking non-working cavity; a diaphragm is arranged in the travelling crane chamber and divides the travelling crane chamber into a travelling crane cavity and a travelling crane non-working cavity;

the piston is connected with a piston push rod, and a ventilation channel of the piston push rod is communicated with the parking non-working cavity; when the piston is not ejected out, the breather valve is positioned in an isolation area of the gas chamber middle body, and the side wall hole of the push rod is blocked; when the piston is ejected, the side wall hole of the push rod can be ejected out of the isolation area of the gas chamber middle body so as to be communicated with the travelling crane cavity.

10. The spring brake air chamber as claimed in claim 9, wherein the output force value of the balance spring can balance the back pressure of the valve core when the piston is ejected rapidly and the volume of the parking non-working chamber is changed and air suction is required.

Technical Field

The invention relates to the technical field of vehicle brake control systems, in particular to a modularized breather valve for a spring brake chamber and the spring brake chamber.

Background

In large commercial vehicle brake systems, spring brake chambers are used as brake actuators. The piston type spring brake air chamber is widely applied to various chassis brake systems of commercial vehicles in domestic and foreign markets due to higher brake output force upper limit and relatively more reliable parking brake structures. However, the piston type parking chamber brake structure has a breathing problem, namely when the piston moves, air in a non-working chamber of the piston needs to be sucked or exhausted from the outside due to volume change in a short time, otherwise, a significant back pressure/negative pressure is formed on the non-working side of the piston to block the movement of the piston; even the air/water tightness of the parking cavity to the outside is damaged, various dust and sewage in the environment of the chassis are sucked, and the sealing performance and the movement flexibility of the piston are affected when the piston is used for a long time. At present, two methods for treating the breathing problem of the piston type parking cavity are mainly adopted: 1) the non-working side of the piston of the parking cavity is communicated with the non-working side of the diaphragm of the driving cavity through a hose, so that the piston moves and breathes from the outside of the air chamber; 2) a breather valve is additionally arranged on a piston push rod in the air chamber to suck/discharge air in the piston non-working chamber through a travelling crane chamber involucra inflation pipeline. The existing piston push rod internal breather valve in the market is mainly provided with a double-valve plane sealing structure.

However, the existing external breathing structure is easy to cause the air/water tightness failure of the parking cavity due to the falling-off of the external hose, and the piston sealing and moving environment can be polluted to gradually fail. And the breather valve in piston push rod of current double valve structure, because design initial position is located the air chamber and drives between the vehicle chamber and the parking chamber working chamber, and the requirement to the valve plane seal is very high, if it is clean inadequately to drive the vehicle chamber working gas circuit, probably have impurity and inhale interior breather valve seal plane position, lead to interior breather valve seal failure. And the fault risk of insufficient driving braking force or even wheel locking in the driving process can be caused according to the severity of the leakage of the internal breather valve. In addition, the inner breather valve with the double-valve structure has a complex structure and large occupied space, is not beneficial to structural modularization, and is also not beneficial to the reduction of the depth volume of the parking cavity in the form of an inner hanging rod in light weight design. The invention mainly aims at overcoming the structural defects of the existing piston push rod internal breather valve in the market, and solves the two problems: 1) stability of sealing between chambers, 2) compactness and ease of modularity of the internal breather valve structure. Therefore, the piston type spring brake chamber with the internal respiration structure can meet higher market requirements.

Disclosure of Invention

The invention aims to provide a modularized breather valve for a spring brake air chamber and the spring brake air chamber, aiming at the structural defects of the breather valve in a piston push rod in the existing spring brake air chamber and solving the two problems: 1) stability of sealing between chambers, 2) compactness and ease of modularity of the internal breather valve structure.

In order to achieve the above purpose, the invention provides the following technical scheme: the modularized breather valve for the spring brake chamber comprises a piston push rod, a ventilation channel is arranged in the piston push rod, the breather valve comprises an end cover main body, a valve core, a guide sleeve and a balance spring, the end cover main body is fixedly arranged at the top of the piston push rod, the guide sleeve is fixedly arranged in the end cover main body, the valve core is movably arranged in the guide sleeve, and the balance spring is arranged between the valve core and the guide sleeve;

a central breathing hole is formed in the sealing plane at the bottom of the guide sleeve and is communicated with a ventilation channel of the piston push rod; one end of the valve core close to the sealing plane is provided with a sealing lip corresponding to the central breathing hole;

a push rod side wall hole is formed in the side wall of the piston push rod and communicated with the inner cavity of the guide sleeve; the outer side wall of the valve core is in clearance fit with the inner side wall of the guide sleeve, and the area of the fit clearance is respectively equal to the ventilation sectional area of the central breathing hole and the ventilation sectional area of the side wall hole of the push rod.

Preferably, the outer side wall of the upper part of the guide sleeve and the top end of the guide sleeve are in clearance fit with the inner side wall and the inner top wall of the end cover main body respectively, and the area of the fit clearance is equivalent to the ventilation sectional area of the side wall hole of the push rod.

Preferably, the backside of the valve element and/or the inner top wall of the end cap body are provided with a protrusion, such that the backside of the valve element and the inner top wall of the end cap body are spaced apart from each other.

Preferably, a spring groove is formed inwards in the middle of the sealing lip on the valve core, a step hole with the sectional area larger than that of the central breathing hole is formed in the upper portion, opposite to the central breathing hole, of the central breathing hole, and two ends of the balance spring abut against the spring groove and steps of the step hole respectively.

Preferably, the end cover main body is in interference fit with the top of the piston push rod.

Preferably, sealing rings are respectively arranged between the end cover main body and the piston push rod at the upper side and the lower side of the side wall hole of the push rod; and a sealing ring is arranged between the outer side face of the lower part of the guide sleeve and the inner side face of the end cover main body.

Preferably, the end cover main body and the piston push rod are integrally formed.

Preferably, the guide sleeve is fixedly arranged in the end cover main body through a limiting piece.

A spring brake air chamber comprises the modularized breather valve for the spring brake air chamber, and further comprises a parking chamber, a traveling chamber and an air chamber middle body positioned between the parking chamber and the traveling chamber, wherein a piston is arranged in the parking chamber, and the parking chamber is divided into a parking cavity and a parking non-working cavity by the piston; a diaphragm is arranged in the travelling crane chamber and divides the travelling crane chamber into a travelling crane cavity and a travelling crane non-working cavity;

the piston is connected with a piston push rod, and a ventilation channel of the piston push rod is communicated with the parking non-working cavity; when the piston is not ejected out, the breather valve is positioned in an isolation area of the gas chamber middle body, and the side wall hole of the push rod is blocked; when the piston is ejected, the side wall hole of the push rod can be ejected out of the isolation area of the gas chamber middle body so as to be communicated with the travelling crane cavity.

Preferably, the output force value of the balance spring can balance the back pressure borne by the valve core when the piston is ejected quickly and the volume of the parking non-working cavity is changed and air suction is needed.

Compared with the prior art, the invention has the advantages that: compared with the existing double-valve plane sealing piston type spring brake air chamber internal breather valve, the design structure of the invention is simpler, the internal volume required by the internal breather valve structure is obviously reduced, and the invention is beneficial to the lightweight design of the piston type spring brake air chamber parking cavity. The valve seal does not need to be exposed under the working pressure of the travelling crane cavity for a long time, and the sealing reliability of the internal breather valve is more stable and excellent. And the design of the integral matching of the valve core, the guide sleeve and the balance spring can be easily modularized, and even if the structure is not used on an independent internal breather valve top cover but is arranged in the integrated piston mandril, the structure can be easily realized.

Drawings

Fig. 1 is a schematic view showing the structure of the open state of the breather valve according to the present invention.

Fig. 2 is a schematic structural view of a closed state of the breather valve in the invention.

FIG. 3 is a schematic structural diagram of a spring brake chamber in a service state according to the present invention.

FIG. 4 is a schematic structural diagram of a service braking state of the spring brake chamber in the invention.

FIG. 5 is a schematic diagram of the spring brake chamber parking brake state of the present invention.

FIG. 6 is a schematic diagram illustrating the service braking state of the breather valve in the present invention.

FIG. 7 is a schematic diagram illustrating the operation of the breather valve in the start/park cut-in state of the present invention.

FIG. 8 is a schematic diagram of the operation of the breather valve hill start/park condition of the present invention.

In the figure: 100. a breather valve; 1. a piston push rod; 2. an end cap body; 3. a guide sleeve; 4. a valve core; 5. a balance spring; 6. a limiting member; 7. sealing the plane; 8. a central breathing hole; 9. a vent passage; 10. sealing the lip; 11. a side wall hole of the push rod; 12. a bump; 13. a seal ring; 14. a parking room; 15. a driving room; 16. a gas cell mesosome; 17. a piston; 18. a parking chamber; 19. a parking non-working chamber; 20. a membrane; 21. a travelling crane cavity; 22. the traveling is not a working chamber.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further specifically described below by way of embodiments in combination with the accompanying drawings.

Example 1

A modularized breather valve for a spring brake chamber is shown in figures 1-2 and comprises an end cover main body 2, a guide sleeve 3, a valve core 4 and a balance spring 5, and other auxiliary parts comprise a plurality of sealing rings 13 for static sealing and a limiting part 6 for limiting and clamping.

The end cover main body 2 is a mushroom head-shaped hollow end cover, the small end is open and is clamped or in interference fit with the open end of the piston push rod 1, and the large end is used as a pushing end cap of the piston push rod 1; the piston push rod 1 is used for pushing the piston to transmit braking force to the push disc assembly through the parking spring acting in the air chamber parking or emergency braking state, and finally acting on the brake to realize braking.

The guide sleeve 3 is fixedly arranged in the end cover main body 2 through a limiting part 6, the whole structure is a hollow cup-shaped cylindrical structural part, the top end is open, the inner side of the bottom is a sealing plane 7, a central breathing hole 8 is arranged in the middle of the sealing plane 7, and the central breathing hole 8 is communicated with a ventilation channel 9 in the piston push rod 1. In this embodiment, the limiting member 6 may adopt a hole retaining ring, an external tooth retaining ring or a claw structure to limit and clamp the guide sleeve 3 in the end cover main body 2.

The valve core 4 is of a two-way valve appearance structure, the outer wall of the valve core is of a regular cylinder shape, and the valve core is movably arranged in a cylindrical inner cavity of the guide sleeve 3; the bottom of case 4 is equipped with the sealed lip 10 of rubber, and sealed lip 10 corresponds with central breathing hole 8, when case 4 reciprocated, can open or shutoff central breathing hole 8.

The balance spring 5 is a small compression spring of a cold coil arranged at a central bearing hole part at the bottom of the guide sleeve 3, the output force of the small compression spring acts on the valve core 4, specifically, a spring groove is inwards formed in the middle of the sealing lip 10 on the valve core 4, a step hole with the sectional area larger than that of the central breathing hole 8 is arranged at the relative upper part of the central breathing hole 8, and two ends of the balance spring 5 are respectively abutted to the steps in the spring groove and the step hole.

In the structure, the side wall of the piston push rod 1 is provided with a push rod side wall hole 11, the side wall of the end cover main body 2 is also provided with a side hole communicated with the push rod side wall hole 11, the outer side wall of the relative upper part of the guide sleeve 3 and the top end of the guide sleeve 3 are respectively in clearance fit with the inner side wall and the inner top wall of the end cover main body 2, and the push rod side wall hole 11 is communicated with the inner cavity of the guide sleeve 3 through the side hole of the end cover main body 2 and the clearance between the guide sleeve 3 and the end cover main body 2; the outer side wall of the valve core 4 is in clearance fit with the inner side wall of the guide sleeve 3 through calculation, so that when the valve core 4 is opened, the side wall hole 11 of the push rod can be communicated with the central breathing hole 8, and further communicated with the ventilation channel 9 in the piston push rod 1, and the breathing function of the breathing valve under a specific condition is realized.

In this embodiment, the ventilation cross-sectional area of the central breathing hole 8, the fit clearance area between the valve core 4 and the guide sleeve 3, the fit clearance area between the outer side wall and the top end of the upper portion of the guide sleeve 3 and the inner side wall and the inner top wall of the end cover main body 2, the ventilation cross-sectional area of the side hole of the end cover main body 2, and the ventilation cross-sectional area of the side wall hole 11 of the push rod are all equal, so that the breathing flow of the breathing valve is relatively stable. The cylindrical inner wall of the guide sleeve 3 and the sealing plane 7 can also ensure the reciprocating motion smoothness of the valve core 4 and the verticality of the sealing plane 7 when the sealing lip 10 is sealed.

In this embodiment, the 4 dorsal sides of case and the interior roof of end cover main part 2 are equipped with lug 12 that misplaces each other respectively, make its dorsal side and the interior roof of end cover main part 2 can keep the interval when case 4 shifts up, thereby when push rod lateral wall hole 11 is located the service chamber of spring brake chamber, the working pressure when the stopper braking can form the backpressure in the dorsal side of case 4 very easily, and then compress tightly case 4, make the seal lip 10 of case 4 block up central breather hole 8, guarantee that brake pressure does not have the leakage, guarantee that the braking of service braking (service brake) is effective.

In the embodiment, in order to realize the sealing of the structural member of the breather valve, the upper and lower sides of the side wall hole 11 of the push rod are respectively provided with a sealing ring 13 between the end cover main body 2 and the piston push rod 1, and the sealing ring 13 is arranged between the outer side surface of the relative lower part of the guide sleeve 3 and the inner side surface of the end cover main body 2; the sealing ring 13 may be a rubber static sealing ring such as an O-ring, a Y-ring or a rectangular ring.

Example 2

The present embodiment is different from embodiment 1 in that in the present embodiment, the end cover main body 2 and the piston push rod 1 are integrally formed, and the design of integrally matching the valve core, the guide sleeve and the balance spring can form a modular design and be installed inside the piston push rod 1, so that the sealing performance between the end cover main body 2 and the piston push rod 1 is more excellent.

Example 3

A spring brake chamber, as shown in figures 3-5, comprising a breather valve 100 as described in embodiment 1 or embodiment 2. The spring brake air chamber also comprises a parking chamber 14, a traveling chamber 15 and an air chamber middle body 16 positioned between the parking chamber 14 and the traveling chamber 15, wherein a piston 17 is arranged in the parking chamber 14, and the piston 17 divides the parking chamber 14 into a parking cavity 18 and a parking non-working cavity 19; the driving chamber 15 is provided with a diaphragm 20, and the diaphragm 20 divides the driving chamber 15 into a driving cavity 21 and a driving non-working cavity 22.

In the above structure, the piston 17 is connected to the piston rod 1, and the ventilation channel 9 of the piston rod 1 is communicated with the parking non-working chamber 19, so that the rod side wall hole 11 is communicated with the parking non-working chamber 19 when the valve core 4 opens the central breathing port 8.

When the piston 17 is not ejected, the breather valve 100 is positioned in the isolation area of the gas chamber middle body 16, the side wall hole 11 of the push rod is positioned between two rubber sealing lines of the isolation area of the gas chamber middle body 16, and the side wall hole 11 of the push rod is blocked; when the piston 17 is ejected, the side wall hole 11 of the push rod can be ejected out of the isolated area of the air chamber middle body 16 so as to be communicated with the traveling cavity 21.

In this embodiment, the output force value of the balance spring 5 can just balance the back pressure borne by the valve core 4 when the piston is rapidly ejected during parking or emergency braking and the volume of the parking non-working chamber 19 is changed and air suction is required, so that in this state, the output force value of the balance spring 5 can enable the central breathing hole 8 to be in an open state. When starting/parking on a hill, the working air pressure of the travelling cavity 21 is far larger than the output force of the balance spring 5, so that the valve core 4 can be driven to move against the output force value of the balance spring 5.

In the embodiment, the working principle is as follows:

when the vehicle is in a running state or a running braking state, referring to fig. 6, the breather valve 100 at the top end of the piston push rod 1 is located in a sealing isolation area at the central part of the air chamber middle body 16, the push rod side wall hole 11 is located between two rubber sealing lines for isolating the running cavity 21 and the parking cavity 18, and neither the working air pressure of the parking cavity 18 nor the working air pressure of the running cavity 21 leaks from the breather valve 100 to the parking non-working cavity 19.

When the parking hand brake is pulled up by the vehicle to enter the parking brake, or the vehicle is in the parking state and the anti-loosening hand brake contacts the parking brake, referring to fig. 7, the piston 17 in the parking chamber 14 moves, the breather valve 100 is located in the driving cavity 21 at the moment, the side wall hole 11 of the push rod is communicated with the driving cavity 21 and the air passage pipe orifice of the driving cavity, air required by the volume change of the parking non-working cavity 19 can be sucked or discharged through the air passage of the driving cavity of the braking system, and the free breathing of the parking non-working cavity 19 through the breather valve 100 is realized.

When a vehicle is in a hill starting/parking state, referring to fig. 8, a driving cavity 21 is inflated during working, a parking cavity 18 is exhausted, a piston 17 is pushed by a parking spring, a piston push rod 1 is pushed out of an isolation area of a middle body 16 of an air chamber, a push rod side wall hole 11 is positioned in the driving cavity 21, after a breather valve 100 sucks a small amount of air of working air pressure in the driving cavity 21, a valve core 4 in the breather valve 100 moves downwards under the action of back pressure of the working air pressure, a sealing lip 10 blocks a central breather hole 8, the working air pressure in the driving cavity 21 cannot leak from the breather valve 100, meanwhile, the movement of the piston 17 is not influenced, and parking braking of the air chamber can be completed quickly.

The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.