JPS5827868Y2 - Master cylinder reservoir tank - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the structure of a reservoir tank of a mask cylinder.

Generally, the relief port that communicates between the mask cylinder and the reservoir tank is closed at the beginning of the forward motion of the piston, so there is a slight play section in the movement stroke of the piston when the relief port is closed, and this play section The brake fluid pressurized by the piston inside the reservoir tank violently squirts out from the relief port into the reservoir tank, creating a so-called fountain phenomenon. This may lead to inconveniences such as leakage from the airtight part of the tank top lid.
In addition, vibrations from the vehicle body etc. cause bubbling at the interface between the air in the reservoir tank and the brake fluid, and as this phenomenon gradually becomes more intense, the entire brake fluid in the reservoir tank foams, causing the brake fluid to contain fine air bubbles. reaches the pressure chamber of the mask cylinder at 1, and pressing the piston only collapses the bubble and no limb pressure is generated, a so-called paper lock phenomenon, resulting in a dangerous situation.

Therefore, in the past, the reservoir tank was divided into two chambers, upper and lower, and the bottom wall of the reservoir was placed opposite the relief port to prevent air bubbles from forming and entering, but the liquid chamber between the bottom wall of the reservoir and the cylinder body was In both cases, agitation of the liquid occurred and air bubbles were generated, and air bubbles that had once entered the master cylinder were not quickly discharged from the liquid chamber to the upper reservoir chamber, resulting in insufficient removal of air bubbles.

Therefore, in view of the above points, the present invention provides a department plate on the bottom wall of the reservoir, which has a small hole at the top and a conical hollow part with an open bottom, so that the part plate can be inserted through the through hole formed in the bottom wall. to collect air bubbles from the mask cylinder into the conical hollow part,
In addition to quickly and easily discharging the brake fluid from the top small hole into the reservoir chamber, the brake fluid in the reservoir chamber is supplied to the mask cylinder through a labyrinth-like passage formed by the reservoir plate and the bottom wall of the reservoir. This ensures that air is removed during injection and replacement work, and also limits the agitation of the brake fluid due to vibrations of the vehicle body, reducing the generation of bubbles due to foaming in the reservoir.
It is characterized by preventing air from entering the pressure chamber even if bubbles are generated in the shattered reservoir tank, and furthermore, by quickly discharging the air that has once entered the mask cylinder into the reservoir.

Hereinafter, the present invention will be explained based on the illustrated embodiments.
is the mask cylinder body, 2 is the mask cylinder body 1
A piston 4 is a mounting portion of a reservoir 5 having a bottom wall 6 integrally formed on the mask cylinder body 1, and the bottom wall 6 and the mask cylinder 1 are connected to each other. A liquid chamber 7 is formed between the bottom part 8 of the liquid chamber 7 and
A relief port 10 and a supply port 11 communicating with the pressure chamber 9 are provided in the pressure chamber 9 .

The bottom wall 6 of the reservoir 5 has a first through hole 12 approximately in the center thereof.
Second through holes 13 are respectively provided on the outside thereof.

14 is a department plate, which has a small hole 15 at the top, a flange 16 at the bottom, an appropriate number of wing-like ribs 17 higher than the top on the outer peripheral wall, and a conical hollow part 18 with an open bottom. The button is attached to the bottom wall 6 so that the conical hollow part 18 covers the first through hole 12, and the liquid chamber is connected to the first passage 19 consisting of the first through hole 12, the conical hollow part 18, and the small hole 15. 7 and the inside of the reservoir 5 are communicated.

Reference numeral 20 designates a reservoir plate, which has a department plate insertion hole 21 in the center, a groove 22 extending to the periphery on the lower surface, and a notch 23 so that a gap exists between the outer end of the groove 22 and the inner wall of the reservoir 5. The flange 16 of the department plate 14 is sandwiched between the screw insertion holes 2 formed in the reservoir plate 20 and the bottom wall 6, respectively.
4° 25 and screws into the female thread 27 of the reservoir mounting part 4 to hold the flange 16 of the department plate 14 between the reservoir plate 20 and the bottom wall 6, and to attach the reservoir plate 20. and the reservoir 5 are fixed to the reservoir mounting part 4, and the liquid chamber 7 and the reservoir are connected by a labyrinth-shaped second passage 28 consisting of the second through hole 13 of the bottom wall 6 of the reservoir 5 and the groove 22 and notch 23 of the reservoir plate 20. 5.

29 is a diaphragm, and 30 is a cap.

In the above embodiment, the second passage 28 is formed by the second through hole 13, the groove 22 of the reservoir plate 20, and the notch 23.
By sandwiching the flange 17 of the reservoir plate 20, a gap is formed between the lower surface of the reservoir plate 20 and the upward direction of the bottom wall 6, and the reservoir plate 20 is formed to have a diameter smaller than the inner diameter of the reservoir 5, so that the outer edge of the reservoir plate 20 and the reservoir A gap may be provided between the inner diameter and the second passage 28 by this gap and the second through hole 13 .

Further, although the hollow portion 16 is shown to have a conical shape, it may have another conical shape.

Next, to explain the operation of the above embodiment, when the mask cylinder body 1 is assembled to the vehicle body and brake fluid is injected into the reservoir 5, or when the brake fluid is replaced, etc., when there is no brake fluid in the reservoir 5. When the brake fluid is supplied into the reservoir 5, while the fluid reaches the height of the small hole 15,
The liquid is filled into the mask cylinder, liquid chamber 7, etc. from the second passage 28, and the air in the mask cylinder, liquid chamber 7, etc. rises and is discharged from the first passage 19, so the liquid passage and the air passage are separate. The air removal work will be carried out promptly.

Furthermore, even after the brake fluid reaches the height of the small hole 15, even if air remains in the mask cylinder, the fluid chamber 7, etc., the air rises through the fluid and flows through the first through hole 12 to the department plate 140.
Since it collects in the conical hollow part 18, it is discharged through the top small hole 15, that is, the first passage 19 as described above.

The conical angle of the conical hollow portion 18 is such that air is guided by the conical surface and easily rises, and the small hole 15 is large enough to allow air to pass through.

In addition, even if the reservoir 5 vibrates due to vibrations of the vehicle body, etc., the wing-like ribs 17 of the department plate 140 reduce vibrations and ripples in the brake fluid, and the air and brake fluid in the reservoir 5 mix violently. When foaming, the air is difficult to form into fine bubbles, and even if bubbles are formed, the first passage opening at the top of the department plate 14 is formed, and the labyrinth-shaped second passage 28 is formed separately, so that the liquid chamber 7
There is little risk of air easily entering the mask cylinder or the piping connected to it through the liquid chamber 7 or the mask cylinder, and even if air remains or enters the first passage 19
By forming the conical hollow part 18 inside, air is easily collected, guided to the conical surface, and quickly discharged into the reservoir 5 through the small hole 15.

Furthermore, even if a water fountain phenomenon occurs from the relief port 10 that occurs during the initial operation stroke, the bottom wall 6, department plate 14
Since the reservoir 5 and the liquid chamber 7 are defined by the reservoir plate 20, there is less stirring of the liquid in the reservoir 5, which reduces the generation of bubbles.

Furthermore, since the ridge 17 on the outer circumferential wall of the department plate 14 is shaped higher than the top, even if the brake fluid in the reservoir 5 decreases and the diaphragm 29 descends, the rib 17
Since it is supported above, the small hole 15 is not blocked.

As described above, in this invention, the liquid chamber and the reservoir that communicate with the Maneta cylinder are made into two passages, so the opening of one passage is made higher than the opening of the other passage, and the other passage is formed in a labyrinth shape. Therefore, when injecting or replacing brake fluid, the air in the pressure chamber, piping, and fluid chamber is removed quickly and reliably, and agitation of the brake fluid due to vibrations of the vehicle body is restricted to prevent air bubbles in the reservoir tank. The occurrence is reduced,
Moreover, even if air bubbles occur, they will not enter the pressure chamber, and even if air bubbles enter the fluid chamber during operation, they will be quickly discharged into the reservoir, and the brake fluid supplied from the reservoir will not be affected. There is little chance of air getting into the pressure chamber, and even if brake fluid is supplied to the pressure chamber by operating the piston, air will not get into the pressure chamber, so air will be prevented from getting trapped, resulting in smooth and stable braking. Braking can be performed.

[Brief explanation of drawings]

The figures show one embodiment of the present invention, in which Fig. 1 is a cross-sectional front view, Fig. 2 is a sectional view taken along the line ■-■ of Fig. 1, Fig. 3 is a sectional view of the bottom of the reservoir, and Fig. 4 is a sectional view of the reservoir. Perspective view of part plate,
FIG. 5 is a perspective view of the reservoir plate, and FIG. 6 is a sectional front view showing the relationship between the department plate and the diaphragm. 1 is a mask cylinder body, 4 is a reservoir attachment part, 5 is a reservoir, 6 is a bottom wall, 7 is a liquid chamber, 10 is a relief port, 11 is a supply port, 12 is a first passage hole, 13 is a second passage hole, 14 is a department plate, 15 is a small hole, 16 is a flange, 17 is a rib, 18 is a conical hollow part, 19 is a first passage, 20 is a reservoir plate, 21 is a department plate insertion hole, 22 is a groove, 23 24 is a notch, 24 is an additional screw, and 28 is a second passage.

Claims (1)

[Scope of utility model registration request] A reservoir having a bottom wall is attached to the reservoir mounting portion of the mask cylinder body, a liquid chamber is defined between the body and the reservoir, and a first through hole is provided at approximately the center of the bottom wall. A department plate is provided with a second through hole on the outside of each hole, a small hole at the top, a flange at the bottom, an appropriate number of ribs higher than the top on the outer peripheral wall, and a conical hollow part with an open bottom. The reservoir plate is attached to the bottom wall so that its conical hollow part covers the first through hole, and the flange of the department plate is sandwiched between the bottom walls. It is fixed to the reservoir mounting part together with the reservoir bottom wall by the mounting screw, and the first passage consisting of the first passage hole, the conical hollow part and the small hole, the second passage hole, and the gap between the lower surface of the reservoir plate and the reservoir bottom wall. and a second passage formed by a gap between the outer edge of the reservoir plate and the inner wall of the reservoir, the liquid chamber and the inside of the reservoir being communicated with each other.