JPH0224254A - Antilock device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an anti-lock device, and more specifically, to an anti-lock device for detecting a locked state of a wheel using a wheel speed detector, a vehicle body speed detector, etc. in an automobile brake stem. When the occurrence of excessive slip due to sudden braking or a sign thereof is detected, the solenoid valve is operated to reduce the brake pressure, thereby suppressing and controlling the braking force to an optimum level.

Conventional technology Conventionally, in a multi-system brake system, one system of the multi-system brake system uses fluid-flowing (hydro-dynamic) pressure generated by a booster, and the other systems use fluid-static pressure generated by a master turn cylinder. Hybrid systems that use (hydrostatic) pressure are known, and when adding an anti-lock function to the pre-king stem, repressurization after depressurization of the system using master cylinder pressure, that is, fluid volume Various methods have been proposed for replenishing using boost pressure. the! As one,
For example, US Pat. No. 4,557,528 discloses a vehicle equipped with a solenoid valve for unlocking and a solenoid valve for switching master nolinder pressure/boost pressure.

Problems to be Solved by the Invention As mentioned above, when multiple solenoid valves are used, the timing of their operation must be selected depending on information from various detection devices, as also described in the US patent specification. However, it has the disadvantage that the number of parts increases and it is not easy to assemble, resulting in high costs.

Furthermore, electrically, selecting the activation timing requires switches, sensors, and wiring, which increases costs.

The present invention has been made in view of the above-mentioned problems, so the master cylinder pressure is normally transmitted to the brake device to the flow rate adjustment valve when unlocking, and when repressurizing when unlocking, the pressure is switched to boost the hydraulic pressure. It is configured to transmit pressure to the brake device, and without using two solenoid valves as in the conventional example, it is possible to use boost pressure and master turn cylinder pressure with an extremely simple configuration, reducing costs. This makes it easy to assemble.

Means for Solving the Problems, That is, the present invention operates the wheel brake device using pressure fluid from the master cylinder when the anti-lock is not activated, and opens the pressure fluid in the brake device when the anti-lock pressure is reduced. In an anti-lock device configured to allow pressure fluid to flow into a reservoir via a pressure reducing valve, and to introduce pressure fluid from a hydraulic booster into the brake device when repressurizing, the master cylinder, the hydraulic booster, the wheel brake device, and the like are provided. A flow rate adjustment valve that communicates with each other through a flow path, and a pressure reducing solenoid valve that communicates with the flow rate adjustment valve and communicates with the reservoir side through a discharge flow path are provided. The sleeve is fitted with a spring that biases the spool in one direction, and is connected to the hydraulic booster, master cylinder, wheel brake device, and pressure reducing solenoid valve side, respectively. The spool that slides within the sleeve is provided with a plurality of radial passages that communicate with and shut off from the passages of the sleeve according to the movement of the spool, and the spool has a plurality of radial passages. A passage is formed that communicates with the passageway and penetrates in the axial direction separated by an orifice, and when the anti-lock is normally not activated, the main passage that communicates the master cylinder and the brake is opened, and when the anti-lock is unlocked, the pressure reducing solenoid valve is opened and the above-mentioned Open the decompression flow path that communicates the brake equipment and the reservoir,
To provide an anti-lock device, characterized in that, when repressurizing after closing a pressure reducing solenoid valve, a pressure regulating flow path is opened that communicates a hydraulic booster and a brake device through an orifice provided in the spool. It is something.

Function As described above, in this device, when the spool fitted in the sleeve moves in the axial direction, the relative positions of the passages formed in the sleeve and the spool change to communicate or block the master cylinder. a main flow path that communicates the brake device and the wheel brake device; a pressure reduction flow path that communicates the brake device and the reservoir via a pressure reduction solenoid valve; and a hydraulic booster and the brake device via an orifice provided in the spool. During normal non-antilock operation, the main flow path is open, the pressure reduction flow path and the pressure adjustment flow path are closed, and the brake device is pressurized by the master cylinder pressure, and the antilock pressure reduction command is When the pressure reducing solenoid valve opens, the spool moves and the main flow path is closed, then the pressure reducing flow path and the pressure regulating flow path are opened, and the brake fluid in the brake device is discharged via the pressure reducing solenoid valve. When the brake pressure is reduced and the pressure reducing solenoid valve is closed, the discharge of brake fluid through the solenoid valve is stopped, and the boost pressure from the hydraulic booster is inflowed through the pressure regulating flow path, thereby increasing the brake pressure. When the pressure is gradually increased and the pressure difference between the brake pressure and the boost pressure becomes less than a certain value as the brake pressure increases, the return spring opens the main flow path and closes the pressure reduction flow path and the pressure regulation flow path. Return to initial state.

In this way, by combining 1 2-position solenoid valve (anti-lock solenoid valve) and 1 flow rate adjustment valve, it is possible to switch between master cylinder pressure and boost pressure, and the mechanism is simple. At the same time, the entire structure can be made smaller and cheaper.

Below, the present invention will be explained in detail with reference to embodiments shown in the drawings.

FIG. 1 schematically shows the entire configuration of a brake system equipped with an anti-lock device according to the present invention, l is a hydraulic booster, 2 is a master cylinder, 3A, 3B, 3C are flow rate regulating valves, 4A, 4B .

4C is a pressure reducing solenoid valve; 5A, 5B, and 5C are anti-lock devices that combine the above-mentioned flow N adjustment valves and pressure reducing solenoid valves; 6A, 6B are left and right front wheels; 7A, 7B
are the left and right rear wheels.

In the hydraulic booster 1, the boost hydraulic pressure is regulated according to the amount of depression of the brake device 8, and this boost pressure presses the master cylinder 2, and the master cylinder 2 also outputs the same pressure as the boost pressure, or the master cylinder A slightly lower pressure than this is generated by a return spring (not shown) installed in the cylinder 2.

The above hydraulic booster 1 is the flow path 9-11 flow mgI regulating valve 3C
, the left and right rear wheels 7A via the flow path 9-2 and the branch flow path 9-3,
Connects to 7B, and brake device L8 when anti-lock is not activated.
Hydraulic fluid is applied to the left and right rear wheels with boost pressure corresponding to the amount of pedal stroke.
A and 7B, while at the time of anti-lock, the pressure reducing solenoid valve 4C is opened, and the working fluid is returned to the reservoir IO from the discharge flow path 9-4. In this way, rear wheels 7A and 7B
On the other hand, the boost pressure is used to operate the flow rate regulating valve 3C both in the non-anti-lock state and when the pressure is re-pressurized after being depressurized.

The hydraulic booster 1 is connected to the front wheels 6A, 6B via a flow path 9-5 branched from a flow path 9-1 to a flow rate regulating valve 3.
A is also connected to the flow rate adjustment valve 3B via a flow path 9-6 branched from the flow path 9-1, and as described later, the front wheels 6A and 6B are boosted only by repressurization after anti-lock pressure reduction. I try to do it using pressure.

On the other hand, the master turn ring-2 communicates with the flow rate adjustment valves 3A and 3B via a flow path 11-1, a branched flow path 11-2, and 11-3.

3B to the left and right front wheels 6A through flow paths 11-4 and 11-5,
6B, and in normal non-antilock conditions, the hydraulic fluid flows into the face rings 6A, 6B with the master cylinder pressure according to the pressing force of the brake pedal 8, and when the pressure is reduced in antilock conditions, the pressure reducing solenoid valves 4A, 4B is opened, and the working fluid is returned to the reservoir 10 from the discharge channel 11-6 and 11-7.

The pressure reducing solenoid valves 4A, 4B, and 4C that open when the anti-lock pressure is reduced are wheel rotation speed sensors (not shown).
The information from the valve is processed by a control computer (not shown) and a valve opening command is given.

As mentioned above, in Figure 1, only the front wheels 6A and 6B are pressurized with master cylinder pressure when anti-lock is not on.
Although repressurization after anti-lock pressure reduction is performed by boost pressure, it goes without saying that the master turn ring 2 can be a tandem master cylinder and the same configuration as the front wheels can be applied to the rear wheels 7A and 7B.

Furthermore, in the embodiment shown in FIG. 1, a tandem type is used as the master turn ring 2, and each pressure outlet of the two chambers of the master cylinder, the flow rate adjustment valve 3A on the front wheel 6A side, and the flow rate adjustment valve on the front wheel 6B side. It is also possible to provide separate channels that directly communicate with the valves 3B.

The feature of the present invention lies in the structure of the flow rate regulating valves 3A and 3B, which will be described in detail below with reference to FIGS. 2 and 3. still,
The structures of the flow rate regulating valves 3A and 3B are the same.

A spool 16 is slidably fitted into the cylindrical sleeve 15 side, and a solenoid pressure reducing valve 4A or 4B (
The inner surface of one end wall 15a in the axial direction of the sleeve 15 that communicates with the spool 1 (hereinafter, only 4A is representatively described) side
Spring I7 is compressed between 6 and spool 16, and the spool 16 is sleeved! 5 toward the other end wall 15b.

The outer circumferential wall 15c of the sleeve 15 has a first introduction passage 18, a second introduction passage 19, a first outlet passage 20. A second lead-out passage 2I is formed. The first introduction passage 18 communicates with the hydraulic booster 1 side, and the second introduction passage! 9 communicates with the master cylinder 2 side, and the first and second outlet passages 20 and 21 communicate with the brake device side of the front wheel 6A or 6B. In addition, an anti-lock lead-out passage 22 is formed in the wall 15a of the sleeve 15 facing the pressure reducing solenoid valve 4A side, and communicates with the reservoir 10 via a discharge passage.

In the spool 16, an axial passage 24.25 is bored through the axial center with an orifice 23 in between, and a radial passageway 24. A first passage 26, a second passage 27, and a third passage 28 are formed. Further, a fourth passage 29 in the radial direction is formed on the outer peripheral wall of the other passage 25, and the fourth passage 29 and the third IIFI passage 28 are located at positions with the orifice 23 interposed therebetween.

A first introduction passage 18, a second introduction passage 19, a first outlet passage 20, which are formed in the sleeve 15. The second lead-out passage 21 is
A first passage 26, a second passage 27 formed in the spool 16,
As the spool 16 moves in the axial direction, the third passage 28 and the fourth passage 29 open and close the first introduction passage 18 and the first passage 26, as will be described later. and the second passage 27, the first outlet passage 20 and the third passage 28.
, the second outlet passage 21 and the fourth passage 29 are opened and closed.

The operation of the flow rate regulating valves 3A and 3B having the above structure will be explained below.

During normal non-antilock operation, as shown in FIG. 2, the spool is biased by the spring 17! 6 is in contact with one end wall 15b of the sleeve. sleeve +5
The relationship between the spool 16 and the second passage 19 of the spool 16 is that the second passage 2 of the spool 16 is connected to the second introduction passage 19 communicating with the master turn ring-2.
7 communicates with each other, and the third passage 28 communicates with the first outlet passage 20.
is in communication with. The other first passage 26, fourth passage 29 and the passage on the sleeve 15 side are blocked off. Therefore, the pressure of the master cylinder 2 is changed from the second introduction passage 19 to the second
The front wheels 6A and 6B are connected to the front wheels 6A and 6B via the main flow path
is transmitted to the brake system. That is, Prekibetal 8
The brake can be controlled by supplying hydraulic fluid from the master turn ring-2 to the front wheel brake device according to the amount of depression.

Incidentally, at this time, as described above, the first introduction passage 18 and the first passage 26 of the spool 16 communicating with the hydraulic booster 1
Since the hydraulic pressure booster 1 and the master cylinder 2 are cut off, the connection between the hydraulic pressure booster 1 and the master cylinder 2 is cut off, and liquids do not mix together.

On the other hand, when the wheel speed detection sensor detects the occurrence of excessive slip or its signs and sets the anti-convex state,
The pressure reducing solenoid valves 4A and 4I3 are energized and open, and the outlet passage 22 of the sleeve 15 (pressure reducing solenoid valve 4A
, 4B from the discharge channel to the reservoir 10 side. Therefore, the working fluid in the axial passage 25 of the spool 16 communicating with the outlet passage 22 is discharged to the reservoir 10 side, and the pressure on the passage 25 side sandwiching the orifice 23 of the spool 16 becomes lower than the pressure in the passage 24. This orifice 23
When the pressure difference on both sides sandwiching the spool 16 becomes larger than the force of the spring 17, the spool 16 moves to the left in the figure against the biasing force of the spring 17 due to the pressure on the passage 24 side. By moving the spool 16, the first outlet 20 and the third
Communication with the passage 28 is cut off and 1. Since the main flow path is closed, the flow of hydraulic fluid to the brake device side is stopped. Then, the second outlet passage 21 and the fourth passage 29 communicate with each other, resulting in the state shown in FIG. 3. That is, the flow path on the brake device side communicates with the second outlet passage 21 - the fourth passage 29 → the axial passage 25 → the outlet passage 22 to form a depressurizing flow path Y, and the flow path on the brake device side communicates with the flow ta. The pressure reducing solenoid valve 4A (4B) passes through the pressure reducing channel of the regulating valve, and the discharge channel and the reservoir 10
The pressure of the brake [r] is reduced, and anti-lock is applied.

In the process in which the spool 16 moves to the left in the drawing to form the reduced pressure passage Y, the relationship between the sleeve 15 and the spool 16 is as follows: the first introduction passage 18 of the sleeve 15 and the first passage 2 of the spool 16.
6 communicate with each other, and then the second introduction passage 19 and the second passage 2
7 is cut off.

The spool 16 communicates with the discharge flow path through the axial passage 25 and the opened pressure reducing solenoid valve 4A, and the pressure decreases.
When the pressure fluid is replenished to the axial passage 24 side of the spool 16 through the passage, it moves to the left in the figure, while the first introduction passage 1
8 and the first passage 26 and the second introduction passage I9 and the second passage 27 are cut off, the spool 16 stops at that position. Therefore, the spool 16 moves and finally the first introduction passage 18, the first passage 26, and the second introduction passage 19 are moved.
The movement of the spool 16 stops at the point where the second passage 27 and the second passage 27 are blocked.

Thereafter, if the differential pressure in the axial passages 24 and 25 on both sides of the orifice 23 becomes larger than the pressure ΔP determined by the cross-sectional area of the spool 16 and the force of the spring 17, the spool 16
moves to the left in the diagram to reach the 1st #person aisle +8 and the 1st aisle 2.
6 is cut off, and conversely, when the differential pressure becomes smaller than the pressure ΔP, the spool 16 moves to the right in the figure to communicate the first introduction passage 18 and the first passage 26. By repeating this action, the differential pressure between the passages 24 and 25 on both sides of the orifice 23 is maintained at ΔP, and the same flow rate as the flow 1 passing through the orifice 23 with a differential pressure of ΔP is transferred from the hydraulic booster 1 to the 1
Introductory passage 18 - first passage 26 - axial passage 24 -> orifice 23 - axial passage 25 are replenished. Therefore, in the pressure reduction process, the amount of flow that flows out from the wheel brake device is equal to the amount that is obtained by subtracting the above-mentioned replenishment amount from the flow that flows out from the pressure reduction solenoid valve 4A (4B).

Release anti-lock pressure reduction control and release pressure reduction solenoid valve 4A
When (4B) is closed with no power supplied, the hydraulic fluid is no longer discharged through the pressure reducing solenoid valve 4A (4B). Therefore, the spool 16 remains in a position where the first introduction passage 18 and the first passage 26 and the second outlet passage 21 and the fourth passage 29 communicate with each other while maintaining the same balance. Therefore,
The pressure liquid from the hydraulic booster 1 is transferred from the first introduction passage 18 to the first
Passage 26 → Axial passage 24 → Orifice 23 → Passage 25
- Pressure regulation flow path Z consisting of the fourth passage 29 and the second derivation adjustment 21
The boost pressure flows into the brake equipment of the front wheels 6A (6B), and repressurizes after anti-lock pressure reduction.

The inflow and outflow to the brake device at this time is the flow rate that passes through the orifice 23 with a pressure difference of △P, and the position of the spool 16 is automatically adjusted so that this flow rate flows through the first introduction passage 18 and the first passage 26. is adjusted to

As the automatic adjustment process described above continues and the differential pressure between the boost pressure and the brake pressure gradually decreases to △P, the force of the spring 17 is greater than the pressure difference on both sides of the orifice 23 of the spool 16. Become stronger. Therefore, spool +6
is pushed back to the original position shown in FIG. 2 by the force of the spring 17, and the main flow path X is formed again.

Effects of the Invention As is clear from the above explanation, according to the present invention, the anti-lock mechanism uses the master cylinder pressure during normal operation in the non-anti-lock state, but uses the boost pressure when repressurizing after the anti-lock. In the built-in brake system, the flow f can be adjusted without using three 2-position solenoid valves or two 3-position solenoid valves as in the past.
In combination with the fi adjustment valve, it is possible to switch between master cylinder pressure and boost pressure in a brake system equipped with the above anti-lock device by using only one two-position solenoid valve. Therefore, compared to the conventional method, the number of solenoid valves can be reduced by two, the structure can be made simpler and smaller, and the number of parts can be reduced to reduce the cost.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram according to an embodiment of the present invention, FIG. 2 is a sectional view of the flow rate regulating valve of the above embodiment, and FIG. 3 is a sectional view showing the operation of the flow rate regulating valve. G... Hydraulic pressure booster 2... Master turn cylinder 3A, 3B, 3C... Flow rate adjustment valve, 4A, 4B, 4C... Pressure reducing solenoid valve, 5A, 5
B, 5C...Anti-lock device, 6A, 6B...Front wheel, 7A, 7B...Rear wheel, lO...Reservoir,
15...Sleeve, 16...Spool, ]
7... Spring, 18-21, 24-29... Passage, 23... Orifice. Patent Applicant: Sumitomo Electric Industries, Ltd. Agent: Patent Attorney Mae Yamaboshi and 2 others Figure 1 Figure 2 Figure 3 68 7A B 25 2B 24

Claims (1)

[Scope of Claims] 1. When the anti-lock is not activated, the wheel brake system is operated by the pressure fluid from the master cylinder, and when the anti-lock pressure is reduced, the pressure fluid in the brake system is operated via the pressure reducing valve that is opened. In an anti-lock device configured to allow pressure fluid to flow into a reservoir and to introduce pressure fluid from a hydraulic booster into the brake device when repressurizing, the master cylinder, hydraulic booster, and wheel brake device are connected to the master cylinder, hydraulic booster, and wheel brake device through respective flow paths. A pressure reducing solenoid valve is provided which communicates with the flow rate regulating valve and communicates with the reverber side via a discharge channel, and the flow rate regulating valve is disposed within the sleeve by sliding the spool in the axial direction. The sleeve is movably fitted in a fluid-tight manner, and a spring is attached to bias the spool in one direction, and passages are formed in the sleeve that communicate with the hydraulic booster, the master cylinder, the wheel brake device, and the pressure reducing solenoid valve, respectively. In addition, the spool that slides within the sleeve is provided with a plurality of radial passages that communicate with and are cut off from the passages of the sleeve according to the movement of the spool, and the spool is provided with a plurality of radial passages that communicate with and are cut off from the passages of the sleeve according to the movement of the spool. A passage that penetrates in the axial direction separated by an orifice is formed, and when the anti-lock is normally not activated, the main passage that communicates the master cylinder and the brake is opened, and when the anti-lock is unlocked, the pressure reducing solenoid valve is opened to connect the brake device and the reservoir. Open the communicating reduced pressure flow path,
An anti-lock device characterized in that, upon re-pressurization after the pressure-reducing solenoid valve is closed, a pressure regulating channel is opened that communicates the hydraulic booster and the brake device through an orifice provided in the spool. 2. Of the two axial passages sandwiching the orifice formed in the spool, one passage becomes part of the main passage when the main passage is configured, and a part of the other axial passage becomes part of the main passage when the pressure reduction passage is configured. The anti-lock device according to claim 1, wherein the anti-lock device is configured to be part of a flow path.