CN2442903Y

CN2442903Y - Double-cavity centre valve type braking main pump

Info

Publication number: CN2442903Y
Application number: CN 00219570
Authority: CN
Inventors: 顾宝铁
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-03-10
Filing date: 2000-03-10
Publication date: 2001-08-15
Anticipated expiration: 2010-03-10

Abstract

The utility model relates to a double-cavity centre valve type brake main pump which is a hydraulic brake main cylinder for automobiles. A double-cavity hydraulic brake main pump assembled by a centre valve assembly composed of a guide sleeve, a positioning ring, a positioning pin, a centre valve rod, a centre valve sealing ring, a piston, and a sealing ring is used to replace a compensating hole with a phi 0.7 mm diameter of a prime main pump and a prime piston assembly in a present cylinder body. The utility model shortens idle motion and brakes sensitively. Particularly, a smooth complete cavity wall is contacted by the flange of a piston sealing ring. The utility model prolongs service life more than three times. A prime secondary cavity is installed in a limiting pin outside by the brake main pump. The limiting pin with a centre hole is used to be moved and screwed in an oil entering tower to reduce oil leakage factors. The utility model has compact external appearance.

Description

Two-chamber central valve formula master brake cylinder

The utility model relates to a kind of two-chamber hydraulic braking master cylinder that brake system of car is used, and it is good that it has a safety performance, the characteristics of long service life.

At present, known two-chamber hydraulic braking master cylinder all is that the compensation orifice at brake chamber wall drill diameter Φ 0.7mm works to regulate oil circuit and switch, every braking once, the lip of elementary main apron and secondary main apron all will squeeze back and forth with Φ 0.7mm hole and wipe once, the apron quick abrasion, reduce the brake safe performance, reduced master cylinder service life.In the industry standard ZB/TT24008-90 of the People's Republic of China (PRC) (replace JB540-64) " automobile hydraulic brake master engineering factor ", require to stand fatique testing at elevated temperature number of times also only 120,000 times [frequency (1000 ± 100)/h * time (120 ± 2) * h ≈ 120,000 times].However, still have the requirement of the above-mentioned standard of a large amount of master cylinder out of reachs in the industry.

The purpose of this utility model provides the compensation orifice that a kind of central valve group that matches each other has replaced the Φ 0.7mm of former piston set and brake chamber wall, and good with the master brake cylinder safety performance of this central valve group, can improve more than three times service life.

Known two-chamber hydraulic braking master cylinder secondary piston banking pin is exposed to the outside, adds with packing seal in case leak-stopping oil, thereby has also just caused the hidden danger of leakage of oil, and is simultaneously also not attractive in appearance.

Second purpose of the present utility model provides a kind of banking pin, can spacingly not have leakage of oil hidden danger and attractive in appearance succinct again.

The purpose of this utility model is achieved in that profile and the specification that keeps former hydraulic braking master cylinder, but cylinder body brake chamber wall does not bore the compensation orifice of Φ 0.7mm, and the chamber wall that contacts with the rubber seal lip is complete smooth.In brake chamber, the as prescribed program two-chamber central valve group of packing into, two-chamber central valve group is formed by elementary group and secondary group.Form by guide pin bushing, sealing ring (or inside and outside O shape circle), jump ring plain cushion, primary piston, limit coil, primary piston seal ring, packing spring seat, elementary inner spring, elementary outer spring seat, elementary spring for elementary group; Secondary group by secondary piston, oppositely apron, banking pin, oil return sheet, secondary seal circle, central seal circle, center valve rod, secondary inner spring, secondary outer spring seat, secondary spring are formed.

One. glancing impact not:

A. primary barrel: primary piston (5) to moving to left, is got back to guide pin bushing (2) locating shoulder place under the application force of elementary spring (11),

And guide pin bushing (2) four paws front end face blocks limit coil (6), and limit coil (6) promotes primary piston seal ring (7) again, away from the beginning of

Level piston (5) right side, thus asphalt channel open, be equivalent to compensation orifice and play channeling,

See Fig. 2.

B. secondary barrel: secondary piston (12) under the application force of secondary spring (21) to moving to left, when moving to banking pin (14)

Be close to the right shoulder of secondary piston (12), secondary piston (12) stops to move to left, and banking pin this moment (14) is released central valve

Bar (18), it drives central seal circle (17) and leaves the right front end face of secondary piston (12), thereby has opened oil circuit

Passage is equivalent to compensation orifice and plays channeling, sees Fig. 3.

Two. glancing impact:

A. primary barrel: primary piston (5) moves right because of being subjected to external force, and the elementary inner spring (9) of compression discharges elastic force, passes through seal ring

Spring perch (8) promotes primary piston seal ring (7) and is close to the right shoulder face of primary piston (5) all the time, has closed the primary barrel oil circuit and has led to

The road, primary barrel is along with the continuation of piston is moved, and pressure strengthens gradually, and promotes secondary work by elementary spring (11)

Plug (12) moves to right.

B. secondary barrel: secondary piston (12) moves right, and center valve rod (18) leaves banking pin (14), secondary in compression

Under the elastic force that inner spring (19) discharges, center valve rod (18) drives central seal circle (17) and is adjacent in secondary piston

Right front end face has been closed asphalt channel, along with piston continue move to right, pressure continues to increase.

Because during the reciprocal braking motion of the rubber seal apron of the primary and secondary valve group of two-chamber central valve group, the lip contact be complete smooth chamber wall, thereby can reach more than three times of traditional braking master cylinder service life.

Again because in the secondary oil-feed of banking pin shift-in tower of band centre hole, thereby can leakage of oil, and outward appearance is succinct.

The utility model is described in further detail below in conjunction with drawings and Examples.

Fig. 1 is embodiment of the present utility model, is applicable to not glancing impact of minicar, farm vehicle, and oil circuit is out the elevation profile constructional drawing of shape.

Fig. 2 is a not glancing impact of the primary barrel that amplified at 2: 1, and oil circuit is out the elevation profile constructional drawing of shape.

Fig. 3 is a not glancing impact of the secondary barrel that amplified at 2: 1, and oil circuit is out the elevation profile constructional drawing of shape.

Among the figure: 1. 4. jump ring, 21. level springs of plain cushion 5. primary piston 6. limit coils, 7. primary piston seal ring 8. packing spring seats, 9. elementary inner spring 10. elementary outer spring seat 11. elementary spring 12. secondary piston, 13. reverse apron 14. banking pin 15. oil return sheets, 16. secondary seal circle 19. level inner springs of 17. central seal circles, 18. center valve rods 20. level outer springs seats of cylinder body 2. guide pin bushings 3. sealing rings (or inside and outside O shape circle)

Claims

1. two-chamber central valve formula master brake cylinder, form by primary barrel and secondary barrel, it is characterized in that this central valve of assembling group in cylinder body, replaced compensation orifice, this central valve group is that primary piston group and secondary piston group are formed, the secondary piston group is the reverse apron of cover on the neck of a secondary piston left side, the sheet of cover oil return earlier on the right neck, overlap the secondary seal circle again, insert the center valve rod that the central seal circle is housed in the right-hand member centre hole, secondary outer spring cover for seat on piston, in adorn secondary inner spring, inner spring one end withstands outer spring the inner, one end withstands the center valve rod, make the central seal circle that is contained on the valve rod be close to the secondary piston right side, secondary spring one end withstands the cylinder body inner bottom part, and an end withstands on the secondary spring perch, stop screw in the secondary oil-feed of cylinder body tower in the precession secondary piston elongated slot (under the application force of spring, it is close to the right shoulder of secondary piston, thereby the center of promotion valve rod makes the central seal circle leave the secondary piston right side); The primary piston group, at the right cover earlier of primary piston shoulder limit coil, overlap the primary piston seal ring again, the claw of packing spring seat inserts the seal ring inner ring from the right side, and elementary inner spring one end top thereon, the other end withstands in the elementary outer spring seat, elementary outer spring one end withstands on the outer spring seat, and an end withstands the secondary piston left end, and guide pin bushing is enclosed within the primary piston left part, guide pin bushing has outer gland sealing in seal ring and piston, the cylinder body, and left end is that jump ring snaps in the cylinder groove.

2. two-chamber central valve formula master brake cylinder according to claim 1 it is characterized in that stop screw is tightened in secondary barrel oil-feed tower, and stop screw drills through the hole.