CN104401312A

CN104401312A - Jiefang 141 main brake valve provided with filter screen

Info

Publication number: CN104401312A
Application number: CN201410627111.5A
Authority: CN
Inventors: 田青锋
Original assignee: CHANGTONG TECHNOLOGY Co Ltd
Current assignee: CHANGTONG TECHNOLOGY Co Ltd
Priority date: 2014-11-10
Filing date: 2014-11-10
Publication date: 2015-03-11
Anticipated expiration: 2034-11-10
Also published as: CN104401312B

Abstract

The invention discloses a Jiefang 141 main brake valve provided with a filter screen. The filter screen is arranged inside the main brake valve. The filter screen is simple in structure, is convenient to install, and can be arranged outside a valve core of the brake valve. The filter screen is directly arranged around the valve core, and solid particles carried in gas can be prevented from entering the valve core, so that the working reliability of the valve core is enhanced greatly, and braking accidents are avoided.

Description

The main brake valve of liberation 141 band filtering net

Technical field

The present invention relates generally to the technical field of the parts of brake valve of car, specifically a kind of main brake valve of liberation 141 band filtering net.

Background technology

Generally all filter is provided with at present in the pipeline of brake system, for filtering the solid particle polluter with gas flowing in tracheae, thus ensure each brake component not by the impact of solid particle polluter, ensure the reliability of its work, but because filter is apart from spool distant of each valve, the gas after filtering can not be avoided before entering spool again by the solid particle pollution of other new generations, sometimes still there will be particulate matter and enter spool, affect the sealing of spool, cause the accident of gas leakage, need to propose new solution.

The brake system of truck of the prior art and heavy goods vehicles is too anxious, the bad control of feel, brake facing is easily caused to heat up rapidly, cause carbonization, directly have influence on braking effect, it is too urgent to brake, also can cause partially sliding, affect resistance to overturning, thus produce insecurity, or unnecessary economic loss.Problem during in order to solve these brakes of truck, the patent of the two-stage cadence braking master valve that our unit successively proposes and three grades of dummy piston assemblies, can export " secondary or three grades of points are stopped "." point is stopped " principle can make pressurized air, forms pulse, be applied to brake facing in the control gentle room of pipeline, and every subpulse is all equivalent to instrument wiping brake facing.Not only can accomplish that brake hubs is combined effectively with brake facing, and further improve brake facing carbonization to a great extent or form adamantine layer, thus avoid the phenomenon of poor stop to occur, reach good braking effect.Critical component in above-mentioned two patents is spring bag card, and because spring bag card shape matching is special, processing technology is complicated, and yield rate is not high, also there is the problem of mounting process complexity in addition, has a great impact the quality of whole main brake valve.

Summary of the invention

In order to solve the problem, the present invention proposes a kind of main brake valve of liberation 141 band filtering net.

Technical scheme of the present invention is: a kind of main brake valve of liberation 141 band filtering net, comprises the upper valve body be bolted together, lower valve body,

Described upper valve body upper end is provided with Middle face on torque arm seat, torque arm seat and is provided with opening, and in this opening, be provided with the cylindrical slide sleeve of upper end closed, sliding sleeve can move up and down in opening; Be hinged on the support otic placode on torque arm seat in the middle part of torque arm, torque arm upper end is provided with the upper end that rotatable pinch roller is pressed in sliding sleeve, and torque arm lower end is provided with the adjustment screw and jam nut that withstand on torque arm seat side;

The first half of upper valve body enclosure interior is provided with the dummy piston chamber of step,

In this dummy piston chamber, be provided with secondary points to stop dummy piston assembly, comprise dummy piston body, spring bag card, tip-lever support, the top of dummy piston body is columnar width dish chamber, and the cavity shape projection that the bottom of dummy piston body is stretched out is body of rod chamber; The top of described tip-lever support is width dish, bottom is attenuate successively the three sections of step bodies of rod stretched out from width dish, be followed successively by first body of rod, second body of rod, the 3rd body of rod from top to down, the hypomere of the 3rd body of rod inserts in the body of rod chamber of dummy piston body bottom, and width dish is arranged in the width dish chamber in dummy piston body by jump ring; Described spring Bao Kawei is columnar structured, and between the step body of rod and the inwall of dummy piston body width dish chamber of tip-lever support, the upper end of spring bag card is provided with inside annular upper overturning, and lower end is provided with flange under outside annular; Spring bag card outer cover is equipped with one-level balance spring, and one-level balance spring to be supported under the lower surface of tip-lever support width dish and spring bag snap ring shape between flange upper surface; Secondary balance spring is provided with between spring bag card inwall and the step body of rod, the lower end of secondary balance spring is supported on the lower surface of dummy piston body width dish chamber, the external diameter of the upper end of secondary balance spring is greater than upper overturning internal diameter, upper overturning internal diameter is more than or equal to the diameter of first body of rod, and the internal diameter of the upper end of secondary balance spring is less than the diameter of first body of rod; Secondary balance spring upper end is L1 to the distance of the step surface of the first body of rod lower end, the step surface of the second body of rod lower end is L2 to the distance of body of rod chamber upper surface, distance between the upper surface of described spring bag card and width dish lower surface is L4, L1 < L2 < L4; The inside of tip-lever support is provided with push rod chamber, between push rod chamber and the upper surface of sliding sleeve, be provided with push rod;

The top of described dummy piston body is provided with the edge turned up, and is provided with retracing spring first between the step of the step dummy piston chamber in the lower surface and upper valve body at this edge; The lower inner surface of the step dummy piston chamber in the outside face of dummy piston body and upper valve body is bearing fit face, and the bottom of the outside face of described dummy piston body is provided with circular groove, is provided with seal ring in this circular groove;

The middle part of described upper valve body is upper valve member cavity, interlayer is provided with between the outside and upper valve body housing of upper valve member cavity, top and the dummy piston chamber of upper interlayer are through, upper valve member cavity sidepiece is provided with the enterprising gas port that level stretches out upper valve body housing, and the sidepiece of upper valve body is also provided with level and stretches out and the upper air extractor duct communicated with upper interlayer; The upper valve hole that inside flange is formed is provided with on the top of upper valve member cavity, on this, valve hole is corresponding with the external end head position of the body of rod chamber that the bottom of described dummy piston body is stretched out, and valve bore dia is greater than the diameter of the external end head of body of rod chamber on this, be provided with valve member in upper valve member inside cavity;

Upper valve member comprises the upper valve of tubular and the upper valve seat of annular, and upper valve seat is sleeved on outside valve, is bearing fit face, and is provided with hermetically-sealed construction between the inwall of upper valve seat and the outer wall of upper valve, upper valve seat is arranged on the lower end of upper valve member chamber by jump ring, be bearing fit face between the outer wall of upper valve seat and the inwall of upper valve member cavity, and be provided with hermetically-sealed construction, the upper end of described upper valve is annular disk body, and inside and outside this annular disk body, both sides form in-flanges and flanging at upper valve end respectively, between this flanging lower surface and upper surface of upper valve seat, be provided with valve spring, the upper surface of the annular disk body of upper valve upper end is provided with sealing gasket for valve, two annular protrusions are provided with at the upper surface of sealing pad, the annular protrusion in outside coordinates with the edge in valve hole and forms valve opening and closing structure, and the outer face of the annular protrusion of inner side and the body of rod chamber of dummy piston bottom forms valve and to exit on-off structure, upper valve core filtering net is provided with between upper valve spring outside and upper valve member cavity inner wall, this spool filtering net comprises the annular arrangement end-rack on top and the annular arrangement end-rack of bottom, be connected to the pillar stiffener between upper and lower annular arrangement end-rack, inside pillar stiffener or outside be provided with columnar filter screen, the upper end of this filter screen is connected with the circular end-rack on top, the lower end of this filter screen is connected with the annular arrangement end-rack of bottom, the annular arrangement end-rack on described spool filtering net top is connected with the upper sealing lip edge that ringwise cross-sectional plane is wedge shape, on this, the upper surface on sealing lip edge is high outside and low outside in the conical surface, for flexibly connecting between upper sealing lip edge and the annular arrangement end-rack on top, the annular arrangement end-rack of described bottom is connected with the lower seal edge that ringwise cross-sectional plane is wedge shape, and the lower surface at this lower seal edge is outer low and inner high in the conical surface, for flexibly connecting between the annular arrangement end-rack of lower seal edge and bottom, the upper surface on upper sealing lip edge contacts with the lower surface in upper valve hole, and the lower surface at lower seal edge contacts with the upper surface of upper valve seat,

Upper valve body bottom is relay piston chamber, relay piston chamber interior is provided with relay piston, the vertical hollow rod body that relay piston comprises center and the piston body be connected to around the body of rod, in piston body outer cover, piston bush is housed, be bearing fit face between the inwall of piston bush and the outer wall of piston body, the inwall of piston bush and relay piston chamber is bearing fit face; The upper end of the hollow rod body of relay piston passes corresponding with the body of rod chamber lower end of dummy piston from the middle part of upper valve; The lower surface of piston body is provided with spring between lower valve body upper end;

The top of lower valve body is lower valve assembly cavity, lower interlayer is provided with between the outside of lower valve assembly cavity and lower valve body housing, top and the lower piston chamber of lower interlayer are through, lower valve assembly cavity sidepiece is provided with the lower admission port that level stretches out lower valve body, and the sidepiece of lower valve body is also provided with level and stretches out and the lower air extractor duct communicated with lower interlayer; The lower valve hole that inside flange is formed is provided with on the top of lower valve assembly cavity, this lower valve hole is corresponding with the hollow rod body lower end position of described relay piston, and this lower valve bore dia is greater than the diameter of the hollow rod body lower end of relay piston, be provided with lower valve assembly in lower valve assembly inside cavity;

Lower valve assembly comprises the lower valve of tubular and the lower valve seat of annular, and lower valve cover for seat is contained in outside lower valve, is bearing fit face, and is provided with hermetically-sealed construction between the inwall of lower valve seat and the outer wall of lower valve, be bearing fit face between the outer wall of lower valve seat and the inwall of lower valve assembly cavity, and be provided with hermetically-sealed construction, the upper end of described lower valve is annular disk body, and inside and outside this annular disk body, both sides form in-flanges and flanging in lower valve end respectively, between this flanging lower surface and upper surface of lower valve seat, be provided with lower valve spring, the upper surface of the annular disk body of lower valve upper end is provided with lower valve packing seal, two annular protrusions are provided with at the upper surface of sealing pad, the annular protrusion in outside coordinates with the edge in lower valve hole and forms lower valve on-off structure, and the annular protrusion of inner side and the hollow rod body lower end of relay piston form lower valve and to exit on-off structure, bottom spool filtering net is provided with between lower valve spring outside and lower valve assembly cavity inner wall, this spool filtering net comprises the annular arrangement end-rack on top and the annular arrangement end-rack of bottom, be connected to the pillar stiffener between upper and lower annular arrangement end-rack, inside pillar stiffener or outside be provided with columnar filter screen, the upper end of this filter screen is connected with the circular end-rack on top, the lower end of this filter screen is connected with the annular arrangement end-rack of bottom, the annular arrangement end-rack on described spool filtering net top is connected with the upper sealing lip edge that ringwise cross-sectional plane is wedge shape, on this, the upper surface on sealing lip edge is high outside and low outside in the conical surface, for flexibly connecting between upper sealing lip edge and the annular arrangement end-rack on top, the annular arrangement end-rack of described bottom is connected with the lower seal edge that ringwise cross-sectional plane is wedge shape, and the lower surface at this lower seal edge is outer low and inner high in the conical surface, for flexibly connecting between the annular arrangement end-rack of lower seal edge and bottom, the upper surface on upper sealing lip edge contacts with the lower surface in lower valve hole, and the lower surface at lower seal edge contacts with the upper surface of lower valve seat,

Exhaust nozzle chamber is provided with in lower valve body lower portion, and being installed with exhaust nozzle by jump ring, this exhaust nozzle comprises urceolus and inner core, and the urceolus of exhaust nozzle is supported on the lower end of lower valve cover for seat, inner core is sleeved on lower valve inside, is bearing fit face between the outer wall of inner core and the inwall of lower valve.

The external diameter of described secondary balance spring mates with the internal diameter of spring bag card, the internal diameter of described secondary balance spring and the diameter matches of second body of rod; The internal diameter of described one-level balance spring mates with the external diameter of spring bag card; Described width dish lower surface is provided with annular groove outside first body of rod; This annular groove width mates with the width of the upper end of spring bag card.

The annular arrangement end-rack on described spool filtering net top, the annular arrangement end-rack of bottom, pillar stiffener, upper sealing lip edge, lower seal edge are the plastic material of integrated injection molding, described cylindrical filter net is stainless steel, the upper end of filtering net and the annular arrangement end-rack hot-melt adhesive paste on top, the lower end of filtering net and the annular arrangement end-rack hot-melt adhesive paste of bottom, the side of filtering net and pillar stiffener hot-melt adhesive paste; The cross-sectional width of the connecting portion between described upper airtight edge and the annular end-rack on top is B1, the cross-sectional width B2 of the annular end-rack on top, and B1 is not more than 1/3 of B2; The cross-sectional width of the connecting portion between described lower airtight edge and the annular end-rack of bottom is B3, and the cross-sectional width B4 of the annular end-rack of bottom, B3 is not more than 1/3 of B4.

The lower end of described exhaust nozzle is provided with dust-proof cushion.

A main brake valve for liberation 141 band filtering net, comprises the upper valve body be bolted together, lower valve body,

The first half of upper valve body enclosure interior is provided with the dummy piston chamber of step, is provided with three grades of points and stops dummy piston assembly in dummy piston chamber,

These three grades of points are stopped dummy piston assembly, comprise dummy piston body, spring bag card, tip-lever support,

The top of dummy piston body is columnar width dish chamber, and the cavity shape projection that the bottom of dummy piston body is stretched out is body of rod chamber;

The top of described tip-lever support is width dish, bottom is attenuate successively the three sections of step bodies of rod stretched out from width dish, be followed successively by first body of rod, second body of rod, the 3rd body of rod from top to down, the hypomere of the 3rd body of rod inserts in the body of rod chamber of dummy piston body bottom, and width dish is arranged in the width dish chamber in dummy piston body by jump ring; Described spring Bao Kawei is columnar structured, and between the step body of rod and the inwall of dummy piston body width dish chamber of tip-lever support, the upper end of spring bag card is provided with inside annular upper overturning, and lower end is provided with flange under outside annular; Spring bag card outer cover is equipped with balance spring first, and balance spring first to be supported under the lower surface of tip-lever support width dish and spring bag card arc between flange upper surface; Balance spring second is provided with between spring bag card inwall and the step body of rod, the lower end of balance spring second is supported on the lower surface of dummy piston body width dish chamber, the external diameter of the upper end of balance spring second is less than upper overturning diameter, upper overturning internal diameter is more than or equal to the diameter of first body of rod, and the internal diameter of the upper end of balance spring second is less than the diameter of first body of rod; Balance spring the third is provided with in body of rod chamber,

Balance spring second upper end is L1 to the distance of the step surface of the first body of rod lower end, the step surface of the second body of rod lower end is L3 to the distance of body of rod chamber upper surface, the upper end of balance spring third is L2 to the distance between the 3rd body of rod lower surface, distance between the upper surface of described spring bag card and width dish lower surface is L, 4, L1 < L2 < L3 < L4;

The external diameter of described balance spring second mates with the internal diameter of spring bag card, the internal diameter of described balance spring second and the diameter matches of second body of rod; The internal diameter of described balance spring first mates with the external diameter of spring bag card; Described balance spring third is rubber spring; Described width dish lower surface is provided with annular groove outside first body of rod; This annular groove width mates with the width of the upper end of spring bag card.

The lower end of described exhaust nozzle is provided with dust-proof cushion.

Technique effect of the present invention is:

The main brake valve inside of this liberation 141 with filtering net is provided with filtering net, this filter screen structure is simple, easy for installation, the spool of the brake activation valve that can load is outside, directly filtering net is arranged on around spool, the solid housing carried in gas can be avoided to enter in spool, thus the functional reliability of significantly poppe tvalve core; Brake accident is avoided to occur.

The main brake valve of this liberation 141 with filtering net, stop dummy piston and three grades of points of the secondary points of its inside is stopped the spring bag card of dummy piston assembly, adopt upper, annular in-flanges, the structure of lower annular flanging, simplify the structure of spring bag card, reduce difficulty of processing and assembly difficulty, can the qualification rate of significantly improving product.

Spring bag card can pass through cutting straight forming, also can carry out one-time formed processing by Sheet Metal Forming Technology, and the course of processing is simple, and the spring fitting of spring bag card inside is also simple many simultaneously.

Accompanying drawing explanation

The cross-sectional view of the main brake valve of this liberation 141 of Fig. 1 with filtering net;

The cross-sectional view of the main brake valve of this liberation 141 of Fig. 2 with filtering net;

Fig. 3 is that the master of spool filtering net in Fig. 1 and Fig. 2 looks cross-sectional view;

Fig. 4 is the C-C cross-sectional view in Fig. 3;

Fig. 5 is the partial enlargement structural representation in Fig. 3.

Fig. 6 is that this secondary points is stopped the main TV structure schematic diagram of dummy piston assembly;

Fig. 7 is that these three grades of points are stopped the main TV structure schematic diagram of dummy piston assembly;

Fig. 8 is the main TV structure schematic diagram of spring bag card;

Fig. 9 is the A-A cross-sectional view of Fig. 8;

Figure 10 is the main TV structure schematic diagram of tip-lever support;

Figure 11 is the B-B cross-sectional view of Figure 10;

1. dust-proof cushions in figure, 2. exhaust nozzle, 3. jump ring, 4.O type circle, 5. lower valve seat, 6. descend valve body, 7.O type circle, 8.O type circle, 9.O type circle, 10. lower valve spring, 11.O type circle, 12. springs, 13.O type circle, 14. piston bush, 15. relay pistons, 16. upper valve bodies, 17. retracing springs, 18. torque arm seats, 19. bolts, 20. sliding sleeves, 21. push rods, 22. dust-proof cushions, 23.O type circle, 24. lower valves, 25. bolts, 26.O type circle, 27. jump rings, 28.O type circle, 29.O type circle, valve seat on 30., valve on 31., valve spring on 32., 33. dummy pistons, 34. tip-lever supports, 35.O type circle, 36. one-level balance springs or balance spring first, 37. spring bag cards, 38. secondary balance springs or balance spring second, 39. jump rings, 40. adjustment screw 41. jam nut 42. bearing pin 43. flat gasket 44. spring cotter 45. roller 46. bearing pin 47. flat gasket 48. spring cotters, 49. torque arm, 51. balance springs third, 52. enterprising gas ports, air extractor duct on 53, 54. times admission ports, 55. times air extractor ducts, 56. upper valve core filtering nets, 57. bottom spool filtering nets

Wherein flange under 36-1. width dish, 36-2. annular groove, 36-3. first body of rod, 36-4. second body of rod, 36-5. the 3rd body of rod, 33-1. upper overturning, 33-2..

Sealing lip edge, the annular end-rack on 102. tops, 103. pillar stiffeners, 104. filtering nets, the annular end-rack of 105. bottoms, 106. lower seal edges on 101. in figure; The upper surface on 101-1. upper sealing edge.

Detailed description of the invention

Embodiment: see Fig. 1,3-5,6, a kind of main brake valve of liberation 141 band filtering nets in 8-11, figure, comprise the upper valve body be bolted together, lower valve body,

The middle part of described upper valve body is upper valve member cavity, interlayer is provided with between the outside and upper valve body housing of upper valve member cavity, top and the dummy piston chamber of upper interlayer are through, upper valve member cavity sidepiece is provided with the enterprising gas port that level stretches out upper valve body housing, and the sidepiece of upper valve body is also provided with level and stretches out and the upper air extractor duct communicated with upper interlayer, the upper valve hole that inside flange is formed is provided with on the top of upper valve member cavity, on this, valve hole is corresponding with the external end head position of the body of rod chamber that the bottom of described dummy piston body is stretched out, and valve bore dia is greater than the diameter of the external end head of body of rod chamber on this, be provided with valve member in upper valve member inside cavity, upper valve core filtering net is provided with between upper valve spring outside and upper valve member cavity inner wall, this spool filtering net comprises the annular arrangement end-rack on top and the annular arrangement end-rack of bottom, be connected to the pillar stiffener between upper and lower annular arrangement end-rack, inside pillar stiffener or outside be provided with columnar filter screen, the upper end of this filter screen is connected with the circular end-rack on top, the lower end of this filter screen is connected with the annular arrangement end-rack of bottom, the annular arrangement end-rack on described spool filtering net top is connected with the upper sealing lip edge that ringwise cross-sectional plane is wedge shape, on this, the upper surface on sealing lip edge is high outside and low outside in the conical surface, for flexibly connecting between upper sealing lip edge and the annular arrangement end-rack on top, the annular arrangement end-rack of described bottom is connected with the lower seal edge that ringwise cross-sectional plane is wedge shape, and the lower surface at this lower seal edge is outer low and inner high in the conical surface, for flexibly connecting between the annular arrangement end-rack of lower seal edge and bottom, the upper surface on upper sealing lip edge contacts with the lower surface in upper valve hole, and the lower surface at lower seal edge contacts with the upper surface of upper valve seat,

Upper valve member comprises the upper valve of tubular and the upper valve seat of annular, and upper valve seat is sleeved on outside valve, is bearing fit face, and is provided with hermetically-sealed construction between the inwall of upper valve seat and the outer wall of upper valve; Upper valve seat is arranged on the lower end of upper valve member chamber by jump ring; Be bearing fit face between the outer wall of upper valve seat and the inwall of upper valve member cavity, and be provided with hermetically-sealed construction; The upper end of described upper valve is annular disk body, and inside and outside this annular disk body, both sides form in-flanges and flanging at upper valve end respectively, between this flanging lower surface and upper surface of upper valve seat, be provided with valve spring; The upper surface of the annular disk body of upper valve upper end is provided with sealing gasket for valve, two annular protrusions are provided with at the upper surface of sealing pad, the annular protrusion in outside coordinates with the edge in valve hole and forms valve opening and closing structure, and the outer face of the annular protrusion of inner side and the body of rod chamber of dummy piston bottom forms valve and to exit on-off structure;

The external diameter of described secondary balance spring mates with the internal diameter of spring bag card, the internal diameter of described secondary balance spring and the diameter matches of second body of rod; The internal diameter of described one-level balance spring mates with the external diameter of spring bag card.

Described width dish lower surface is provided with annular groove outside first body of rod; This annular groove width mates with the width of the upper end of spring bag card.

The annular arrangement end-rack on described spool filtering net top, the annular arrangement end-rack of bottom, pillar stiffener, upper sealing lip edge, lower seal edge are the plastic material of integrated injection molding, described cylindrical filter net is stainless steel, the upper end of filtering net and the annular arrangement end-rack hot-melt adhesive paste on top, the lower end of filtering net and the annular arrangement end-rack hot-melt adhesive paste of bottom, the side of filtering net and pillar stiffener hot-melt adhesive paste; The cross-sectional width of the connecting portion between described upper airtight edge and the annular end-rack on top is B1, the cross-sectional width B2 of the annular end-rack on top, and B1 is not more than 1/3 of B2; The cross-sectional width of the connecting portion between described lower airtight edge and the annular end-rack of bottom is B3, the cross-sectional width B4 of the annular end-rack of bottom, B3 is not more than 1/3 of B4, connecting portion is narrow to be beneficial to it and to be out of shape under pressure, make the end face on sealing lip edge better and other parts fit, sealing effectiveness is better, connecting portion is more narrow better, just depict the relation of B1 and B2 in accompanying drawing 3, due to B3 and B4 positional symmetry, there is no need again to indicate in the drawings.

The lower end of described exhaust nozzle is provided with dust-proof cushion.

Working process:

After driver's push down on the pedal, act on push rod, tip-lever support is first descending under push rod effect, first to the effect of one-level balance spring, it is made to compress with the descending of tip-lever support, after its stroke L1 completes, the first body of rod lower surface of tip-lever support and secondary balance spring upper-end contact, then one-level balance spring and secondary balance spring co-operation;

In order to further description structure herein, need to select suitable one-level balance spring and secondary balance spring, the rigidity of described one-level balance spring is greater than the rigidity of secondary balance spring, and this dummy piston assembly installs the lower surface that the lower flange of spring bag card is pressed onto width dish chamber by rear stage balance spring; First act on one-level balance spring when tip-lever support is descending like this, after the stroke of L1 completes, act on firsts and seconds balance spring more simultaneously, two spring its effects side by side, thus form twice buffering.

Another situation is exactly select the spring that just mates with spring bag card internal height of length as secondary balance spring, so just need not limit the rigidity of secondary balance spring, also can realize secondary buffer.

After the upper valve in valve body and lower valve are opened, first other flowing through will filter through filter screen, and filtering net is cylindrical shape, are all filtering surfaces at one week, even if just also can also breathe freely at other positions to the areas of blockage of mouth of entering, are not easy to block.

Embodiment two: see Fig. 2,3-5,7, a kind of main brake valve of liberation 141 band filtering nets in 8-11, figure, comprise the upper valve body be bolted together, lower valve body,

The external diameter of described balance spring second mates with the internal diameter of spring bag card, the internal diameter of described balance spring second and the diameter matches of second body of rod; The internal diameter of described balance spring first mates with the external diameter of spring bag card; Described balance spring third is rubber spring.

The lower end of described exhaust nozzle is provided with dust-proof cushion.

Working process:

After driver's push down on the pedal, act on push rod, tip-lever support is first descending under push rod effect, first to the effect of balance spring first, makes it compress with the descending of tip-lever support, after its stroke L1 completes, 3rd body of rod lower end of tip-lever support contacts with balance spring third, now balance spring third and the combined action of balance spring first, after its L2 stroke completes, first body of rod lower surface of tip-lever support and balance spring second upper-end contact, now balance spring first, balance spring third and balance spring second co-operation;

In order to further description structure herein, need to select suitable balance spring first and balance spring second, the rigidity of described balance spring first is greater than the rigidity of balance spring second, and this dummy piston assembly installs the lower surface that the lower flange of spring bag card is pressed onto width dish chamber by back balance spring first; First act on balance spring first when tip-lever support is descending like this, after the stroke of L2 completes, act on balance spring first, second, third more simultaneously, three spring its effects side by side.

Another situation is exactly select the spring that just mates with spring bag card internal height of length as balance spring second, so just need not limit the rigidity of balance spring second.

Claims

1. liberate a main brake valve for 141 band filtering nets, comprise the upper valve body be bolted together, lower valve body,

2. the main brake valve of liberation 141 according to claim 1 with filtering net, is characterized in that: the external diameter of described secondary balance spring mates with the internal diameter of spring bag card, the internal diameter of described secondary balance spring and the diameter matches of second body of rod; The internal diameter of described one-level balance spring mates with the external diameter of spring bag card; Described width dish lower surface is provided with annular groove outside first body of rod; This annular groove width mates with the width of the upper end of spring bag card.

3. the main brake valve of liberation 141 according to claim 1 with filtering net, it is characterized in that: the annular arrangement end-rack on described spool filtering net top, the annular arrangement end-rack of bottom, pillar stiffener, upper sealing lip edge, lower seal edge are the plastic material of integrated injection molding, described cylindrical filter net is stainless steel, the upper end of filtering net and the annular arrangement end-rack hot-melt adhesive paste on top, the lower end of filtering net and the annular arrangement end-rack hot-melt adhesive paste of bottom, the side of filtering net and pillar stiffener hot-melt adhesive paste; The cross-sectional width of the connecting portion between described upper airtight edge and the annular end-rack on top is B1, the cross-sectional width B2 of the annular end-rack on top, and B1 is not more than 1/3 of B2; The cross-sectional width of the connecting portion between described lower airtight edge and the annular end-rack of bottom is B3, and the cross-sectional width B4 of the annular end-rack of bottom, B3 is not more than 1/3 of B4.

4. the main brake valve of liberation 141 according to claim 1 with filtering net, is characterized in that: the lower end of described exhaust nozzle is provided with dust-proof cushion.

5. liberate a main brake valve for 141 band filtering nets, comprise the upper valve body be bolted together, lower valve body,

6. the main brake valve of liberation 141 according to claim 5 with filtering net, is characterized in that: the external diameter of described balance spring second mates with the internal diameter of spring bag card, the internal diameter of described balance spring second and the diameter matches of second body of rod; The internal diameter of described balance spring first mates with the external diameter of spring bag card; Described balance spring third is rubber spring; Described width dish lower surface is provided with annular groove outside first body of rod; This annular groove width mates with the width of the upper end of spring bag card.

7. the main brake valve of liberation 141 according to claim 5 with filtering net, it is characterized in that: the annular arrangement end-rack on described spool filtering net top, the annular arrangement end-rack of bottom, pillar stiffener, upper sealing lip edge, lower seal edge are the plastic material of integrated injection molding, described cylindrical filter net is stainless steel, the upper end of filtering net and the annular arrangement end-rack hot-melt adhesive paste on top, the lower end of filtering net and the annular arrangement end-rack hot-melt adhesive paste of bottom, the side of filtering net and pillar stiffener hot-melt adhesive paste; The cross-sectional width of the connecting portion between described upper airtight edge and the annular end-rack on top is B1, the cross-sectional width B2 of the annular end-rack on top, and B1 is not more than 1/3 of B2; The cross-sectional width of the connecting portion between described lower airtight edge and the annular end-rack of bottom is B3, and the cross-sectional width B4 of the annular end-rack of bottom, B3 is not more than 1/3 of B4.

8. the main brake valve of liberation 141 according to claim 5 with filtering net, is characterized in that: the lower end of described exhaust nozzle is provided with dust-proof cushion.