JP2748634B2 - Reservoir tank for master cylinder - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a reservoir tank for a master cylinder used for a brake device of an automobile or the like.

(Prior art) A tandem master cylinder of a brake device for a vehicle such as an automobile divides a hydraulic system into two systems for a front wheel and a rear wheel (or for a left front wheel and a right rear wheel, and for a right front wheel and a left rear wheel). It was done. The reason why the hydraulic systems are separated is that, when a failure (for example, liquid leakage) occurs in one of the hydraulic systems, the other hydraulic system acts to prevent braking failure.

A tandem master cylinder 1 (hereinafter referred to as a master cylinder 1) shown in FIG. 5 is one in which a hydraulic system is separated into two front and rear systems for a front wheel 2 and a rear wheel 3, and a hydraulic system shown in FIG. Are separated into two systems by crossing a front wheel 2 and a rear wheel 3. In both figures, the hydraulic system on the side closer to the vacuum servo 4 for correcting the braking force of the master cylinder 1 among the two systems is referred to as a primary system 5 and the distant side is referred to as a semandary system 6. 5 and 6, reference numeral 7 denotes a reservoir tank for supplying oil to the master cylinder 1.

The master cylinder 1 has a cylinder mechanism (not shown) for generating a hydraulic pressure, and a reservoir provided at an upper portion of the cylinder mechanism and connected to two oil liquid receiving ports of the cylinder mechanism for storing the oil supplied to the cylinder mechanism. And a tank 7. Hereinafter, the reservoir tank 7 for the master cylinder will be described. FIG. 7 is a plan view of a conventionally used reservoir tank 7 with a cap, a filter, and a float removed. FIG. 8 is a longitudinal sectional view thereof.

Inside the reservoir tank body 8 (hereinafter, referred to as the body 8) of the reservoir tank 7, the inside of the body 8 has two chambers, that is, a first chamber 9 for storing an oil solution of the primary system 5 and an oil solution of the secondary system 6 are stored. A partition wall 11 is provided so as to be orthogonal to the front-rear direction of the vehicle (the left side is the front side in FIGS. 7 and 8). further,
Inside the main body 8, a partition wall 11 is provided, which surrounds the partition wall 11 near the peripheral wall avoiding the lower master cylinder 1 and has a substantially cylindrical partition 12 centered on the partition wall 11. Inside the partition 12, two small chambers 13 and 14 are formed by the partition wall 11. In the vicinity of the center of the reservoir tank body 8 of the partition wall 12, communication passages 15, 16 for communicating both sides of the partition wall 12 are formed.
It is formed in a symmetrical position across 1. These communication holes 15,
16, the first room 9 and the small room 13, and the second room 10 and the small room
14 will communicate with each other. In addition, a float (not shown) for detecting a decrease in the oil liquid is disposed inside the partition wall 12.

Reference numeral 17 denotes a port provided to the primary system 5 provided in the first room 9, and reference numeral 18 denotes a port provided to the secondary system 6 provided outside the second room. These ports
17 and 18 are aligned with the oil liquid receiving ports (not shown) formed in the linear master cylinder 1, so that the ports
The straight line connecting the lines 7 and 18 is orthogonal to the partition wall 11. In the figure, reference numeral 4 denotes a vacuum servo.

Such a master cylinder reservoir tank 7 is usually filled with an oil liquid up to the MAX level 19 (see FIG. 8). In this state, when the brake pedal is depressed, the oil liquid in the reservoir tank 7 reaches the wheel cylinders (not shown) from the respective ports 17 and 18 via the hydraulic system separated into two, and the wheel braking force Is given. If it is assumed that a liquid leak occurs in one system, for example, the secondary system 6, and the oil liquid flows out, the oil liquid in the second chamber 10 and the small chamber 14 communicating with the second chamber 10 is emptied. Become
As shown in FIG. 9, the oil liquid in the reservoir tank 7 is reduced to the height of the partition wall 11 of the small chamber 13 communicating with the first chamber 9 to maintain the amount. As a result, even when the hydraulic system of the secondary system 6 is damaged, the hydraulic fluid that generates the hydraulic pressure remains in the hydraulic system of the primary system 5 and the braking cannot be disabled.

In some cases, a liquid level detecting device of a reservoir tank for a tandem master cylinder is provided inside a blind plug that closes an opening end of a liquid communication hole (Japanese Utility Model Publication No. 61-31889).

(Problems to be Solved by the Invention) However, in the conventional reservoir tank for a master cylinder having such a configuration, in particular, when liquid leakage occurs in the secondary system, the first chamber and the second chamber that communicate with the primary system. The braking is applied by the oil liquid maintained in the small chamber communicating with the first chamber. In this manner, the oil liquid is maintained only in the first chamber and the small chamber communicating with the first chamber many times. When the brake pedal is depressed, there is a problem that the oil liquid in the first chamber and the small chamber communicating with the first chamber flows into the small chamber communicating with the second chamber over the partition wall due to inertia force (No. See Figure 10). If the movement of the oil liquid continues, the oil liquid on the primary system side decreases, and air enters from the port 17 in the first chamber (see FIG. 11), which may cause a problem in the hydraulic system.

(Means for Solving the Problems) The present invention has been made to solve the above-mentioned problems. As shown in FIG. 1, the present invention is directed to a reservoir tank body 22 communicating with a master cylinder 21. A partition wall 23 that defines the inside of the reservoir tank body 22 is provided so as to be orthogonal to the front-rear direction of the vehicle body, and a barrier wall 29 is formed by extending the upper end of the partition wall 23 toward the rear of the vehicle body. It is. Also, a partition wall surrounding a part of the partition wall 23 is provided on the partition wall 23.
26, the upper end of the partition wall 23 inside the partition wall 26 is extended toward the rear of the vehicle body to form a barrier 29, and the partition wall
The passage 26 may be provided with communication passages 30 and 31 that communicate the inside and the outside of the partition 26. Furthermore, the height of the partition wall 23 inside the partition 26 is
It is desirable that the height be lower than the height of the partition wall 23 outside the partition wall 26.

(Operation) With the above-described configuration, when the oil liquid is maintained only in one chamber (the first chamber 24 and the small chamber 27) separated in the reservoir tank body 22, the driver operates the brake pedal. No matter how many times the step is performed, a barrier 29 extending toward the rear of the vehicle body is formed at the upper end of the partition wall 23, so that the inertial force causes the inside of one of the chambers (the first chamber 24 and the small chamber 27) to move. Does not flow over the partition wall 23 and flow into the other chamber (the second chamber 25 and the small chamber 28). Therefore, 1
The oil liquid remaining in the other chamber (the first chamber 24 and the small chamber 27) does not decrease and no air enters the hydraulic system.

Further, a partition wall 26 surrounding a part of the partition wall 23 is provided, and an upper end portion of the partition wall 23 inside the partition wall 26 is extended rearward of the vehicle body to form a barrier 29, and the partition wall 26 is provided on the partition wall 26. By providing communication passages 30 and 31 that communicate the inside and outside of the tank, it is possible to secure the amount of oil liquid to be reduced in several stages, and to arrange a float for checking the amount of oil liquid reduction inside the partition. it can. Further, by setting the height of the partition wall 23 inside the partition wall 26 lower than the height of the partition wall 23 outside the partition wall 26, the maximum capacity of the oil amount of each hydraulic system can be ideally held.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. FIG. 1 is a plan view of a master cylinder reservoir tank 20 according to the present invention, in which a cap, a filter, and a float are removed.
FIG. 2 is a sectional view thereof.

The reservoir tank 20 is provided above the master cylinder 21, and the reservoir tank main body 22 (hereinafter, referred to as the main body 22) is formed in a cylindrical shape. Further, a partition wall 23 is provided in the main body 22 perpendicularly to the front-rear direction of the vehicle so as to separate the inside of the main body 22 into two chambers from the bottom upward. The master cylinder 21 is a tandem master cylinder in which a hydraulic path is divided into a primary system and a secondary system.

The chamber defined in the main body 22 by the partition wall 23 stores the primary system oil liquid, stores the first chamber 24 communicating with the primary system and the secondary system oil liquid, and communicates with the secondary system. The second room 25 is two rooms. This partition
23 form chambers 24 and 25 which are divided into front and rear portions in the front and rear direction of the vehicle body (the left side is the front side in FIGS. 1 and 2). further,
In the main body 22, a substantially cylindrical partition wall 26 centered on the partition wall 23 near the peripheral wall avoiding the lower master cylinder 21 is a partition wall.
It is provided from the bottom surrounding 23. Inside the partition 26, that is, inside the partition 26, two small chambers 27 and 28 are formed by the partition wall 23 inside.

The partition wall 23 inside the partition wall 26 has two hydraulic systems:
This is for determining and maintaining the maximum capacity of each oil liquid in the primary system and the secondary system (in FIGS. 1 and 2, the right side of the partition wall 23 is the primary system and the left side is the secondary system). However, as the height is increased, the maximum capacity of each system becomes smaller.
The height of the inner partition wall 23 is set to an appropriate height, that is, lower than the height of the partition wall 23 outside the partition 26. A partition wall 23 is formed at the upper end of the partition wall 23 inside the partition wall 26 so as to extend toward the rear of the vehicle body.

In this partition wall 23, a float (not shown) for checking the decrease of the oil liquid is arranged. The float is equipped with a magnet and descends due to a decrease in oil liquid, and operates a reed switch provided at a lower portion of the main body 22 and the like to turn on an alarm lamp provided in a driver's seat or the like to notify the decrease of oil liquid. It has become.

In the partition 26, communication passages 30, 31 for communicating the inside and outside, that is, the first chamber 24 and the small chamber 27, and the second chamber 25 and the small chamber 28, respectively, are located at symmetrical positions across the partition wall 23. Is formed. A port 32 communicating with the primary system is formed at the bottom of the first chamber 24 of the main body 22, and a port 33 communicating with the secondary system is formed at the bottom of the second chamber 25, respectively.

The master cylinder reservoir tank 20 configured as described above is normally filled with the oil liquid up to the Max level 34 (see FIG. 2). In this state, when the brake pedal is depressed, the oil liquid in the reservoir tank 20, that is, the first
The oil liquid in the chamber 24 and the small chamber 27 reaches the wheel cylinder from the port 32 via the primary system of the master cylinder 21, and the oil liquid in the second chamber 25 and the small chamber 28 passes from the port 33 to the secondary system of the master cylinder 21. After that, it reaches the wheel cylinder and brakes the respective wheel. If a problem (liquid leakage, etc.) occurs in the secondary system,
A second chamber 25 in the main body 22 and a small chamber communicating with the second chamber 25
The oil liquid 28 is empty, and the oil liquid in the main body 22 is only the primary system oil liquid. And the amount is the partition wall 23 of the partition 26
And the amount is maintained (see FIG. 3). Hydraulic pressure can be generated by the amount of the oil liquid in the primary system, and braking failure can be avoided.

In this manner, in a state where the oil liquid is maintained only in the first chamber 24 and the small chamber 27 communicating with the first chamber 24, even if the driver steps on the brake pedal several times, the partition wall in the partition wall 26 is formed. Since a barrier 29 extending toward the rear of the vehicle body is formed at the upper end of the 23, the oil liquid in the first chamber 24 and the small chamber 27 will not disperse due to the inertia force when the brake is applied. It is blocked by the barrier 29 and does not get over the partition 23 (see FIG. 4). Therefore, the oil liquid in the first chamber 24 and the small chamber 27 does not decrease, and air does not enter the oil liquid system.

(Effects of the Invention) The present invention is configured as described above, and has the following effects. For example, if the hydraulic system leaks and only one side of the oil is defined, no matter how many times the driver depresses the brake pedal, the upper end of the partition wall will be in the rearward direction of the vehicle. Is provided, the oil liquid which is about to flow out due to inertial force is blocked by the barrier, and does not flow over the partition wall from one side to the other side. Therefore, the oil liquid does not decrease, and no air enters the hydraulic system, so there is no room for braking failure.
In addition, a partition wall surrounding a part of the partition wall is provided, the upper end of the partition wall inside the partition wall is extended rearward to form a barrier, and further, the partition wall has a communication passage communicating between the inside and the outside of the partition wall. With this arrangement, the amount of the oil liquid can be secured in several steps, and the oil liquid which is about to flow out is prevented by the barrier, so that the oil does not cross the partition wall, thereby avoiding a problem in the hydraulic system. Further, since the height of the partition wall inside the partition wall is made lower than the height of the partition wall outside the partition wall, the maximum capacity of the oil amount of the hydraulic system can be ideally held, so that problems in the hydraulic system can be prevented.

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of a reservoir tank for a master cylinder according to the present invention, FIG. 2 is a sectional side view taken along the line II-II of FIG. 1, and FIG. FIG. 4 is a cross-sectional side view of the reservoir tank showing a state where the oil liquid has not climbed over, FIG. 5 and FIG.
FIG. 7 is a schematic view showing a piping diagram of two systems of a master cylinder, FIG. 7 is a plan view showing a conventional reservoir tank for a master cylinder, FIG. 8 is a sectional side view taken along line VIII-VIII in FIG. 9 to 11 are cross-sectional side views showing a state in which the oil liquid in the reservoir tank is reduced. 22 Reservoir tank body 23 Partition wall 26 Partition wall 30, 31 Communication passage

Claims (3)

(57) [Claims] A partition wall defining the inside of the reservoir tank body is provided in the reservoir tank body communicating with the master cylinder so as to be orthogonal to the front-rear direction of the vehicle body, and the upper end of the partition wall is located rearward of the vehicle body. A reservoir tank for a master cylinder, wherein the reservoir tank is extended to face and forms a barrier. 2. A partition wall surrounding a part of the partition wall is provided on the partition wall, and an upper end portion of the partition wall inside the partition wall is extended rearward of the vehicle body to form a barrier. 2. The reservoir tank for a master cylinder according to claim 1, wherein a communication passage communicating between the inside and the outside of the partition is provided in the partition. 3. The reservoir tank for a master cylinder according to claim 2, wherein the height of the partition wall inside the partition wall is lower than the height of the partition wall outside the partition wall.