JPS6158341B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an anti-skid device for a vehicle braking system, and in particular to an anti-skid device for a vehicle brake system, and in particular to a type of anti-skid device that quickly increases the initial braking oil pressure acting on the wheel cylinder and gently reduces the oil pressure from the second time onwards. To provide an anti-skid device which can be operated to quickly raise the oil pressure for the second and subsequent times as necessary. The above-mentioned "wheel cylinder" corresponds to a caliper cylinder when the braking device is a disc brake, and in this specification, both of these are included.

In vehicle braking systems, anti-skid devices are employed to prevent wheels from locking up or close to locking during braking and to achieve safe and reliable braking. In this case, in order to obtain smooth braking by slowing down the rising speed or both the rising and falling speed of the oil pressure in the wheel cylinder during braking operation, a bypass oil passage is installed in the middle of the hydraulic oil passage from the master cylinder to the wheel cylinder. (auxiliary hydraulic oil passage) is provided and a restriction orifice is provided in the bypass oil passage.

However, in conventional anti-skid devices of this type, once the on-off valve installed in parallel with the limiting orifice is closed, it remains closed until braking is complete, and the oil pressure in the wheel cylinder always increases slowly, except at the beginning of braking. I could only do so.
For this reason, even if the frictional resistance of the road surface or the like changes during a braking operation and it is necessary to rapidly increase the oil pressure midway through the braking operation, it has been impossible to perform control accordingly.

The purpose of the present invention is to solve these conventional drawbacks, and it is possible to speed up or slow down the rise or both of the rise and fall of the oil pressure in the wheel cylinder as necessary even during braking. An object of the present invention is to provide an anti-skid device for a vehicle braking device that enables flexible control.

That is, according to the present invention, a hydraulic oil path that supplies hydraulic pressure from a master cylinder to a wheel cylinder, a first on-off valve and a second on-off valve that are provided in series with each other in the middle of the hydraulic oil path, and a master cylinder and a wheel cylinder. a return oil passage provided between the cylinders in parallel with the hydraulic oil passage, and a return pump provided in the return oil passage;
A check valve provided on each of the upstream and downstream sides of the return pump and allowing flow only in the return direction, an auxiliary hydraulic oil path that bypasses the second on-off valve, and a restriction orifice provided in the auxiliary hydraulic oil path; A reflux check valve that is provided in the return oil passage on the master cylinder side than the check valve downstream of the return pump and allows flow only in the return direction, and between the check valve downstream of the return pump and the reflux check valve. An anti-skid device for a vehicle braking device, comprising an oil chamber to which a hydraulic pressure is supplied, and a mover that receives the hydraulic pressure of the oil chamber and holds the second on-off valve in a closed position, the anti-skid device communicating with the oil chamber. An anti-skid device is provided, characterized in that an open oil passage is provided, and a third on-off valve is provided in the open oil passage.

Since the present invention has the above configuration, when the third on-off valve is in one position, the open oil passage is shut off and the second on-off valve is brought into the closed state using the oil pressure maintained in the oil chamber. By doing so, the oil pressure in the wheel cylinder is gradually increased. However, when the third on-off valve is moved to the other position as necessary, the open oil passage is opened to release the oil pressure in the oil chamber, and the oil pressure in the oil chamber is released. By opening the on-off valve, the oil pressure of the wheel cylinder can be quickly increased.

In the above configuration, if the second on-off valve is configured with a check valve and a mover that biases the check valve to the open position, and becomes a simple check valve in the closed position, the wheel The oil pressure of the cylinder can be rapidly lowered at all times.

Furthermore, if the second on-off valve is configured to be an ON/OFF valve so as to block bidirectional flow at its closed position, both the increase and decrease of the wheel cylinder oil pressure can be performed gradually, and the The three on-off valves can be moved to rapidly increase and decrease the wheel cylinder oil pressure.

Furthermore, if the open passage is configured to connect the oil chamber to the upstream side of the return pump in the return oil passage, the hydraulic oil from the oil chamber can be pressurized again by the return pump and used as an effective fluid. I can do it.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing the state of the anti-skid device of the present invention before braking. Here, when a master cylinder 16 is actuated by a brake lever 14 attached to a handle 12 of a motorcycle or the like, the Hydraulic pressure is generated within the 1 oil passage 18.

Note that the illustrated master cylinder is operated by a brake lever, such as in a motorcycle, but
In automobiles, it is usually operated by a foot pedal. The present invention is equally applicable to any of these cases and includes both of these cases.

The hydraulic pressure generated in the first oil passage 18 is sent to the second oil passage 22 through the first on-off valve 20 in the open position (upper position in the illustration), and further through the second on-off valve 24 in the open position. The oil reaches the third oil passage 26 and reaches the wheel cylinder 28 to brake the wheels.

Note that the wheel cylinder 28 corresponds to a caliper cylinder when the braking device is a disc brake, and the term "wheel cylinder" in this specification includes both of these.

Further, the first oil passage 18, the second oil passage 22, and the third oil passage 26 constitute a hydraulic oil passage for supplying braking oil pressure from the master cylinder 16 to the wheel cylinder 28.

Between the upstream side and the downstream side of the second on-off valve 24, there is an auxiliary hydraulic oil passage 30 that bypasses the second on-off valve.
A restriction orifice 32 is provided in the auxiliary hydraulic oil passage. Therefore, at the start of braking, hydraulic pressure is transmitted through both the second on-off valve 24 and the limiting orifice 32, and the hydraulic pressure in the wheel cylinder 28 increases rapidly, increasing the initial braking force response speed and causing the wheels to move in a short period of time. is suddenly braked.

Thereafter, when the deceleration of the vehicle increases and reaches a predetermined value, that is, when the wheels reach a state on the verge of locking, the first on-off valve 20 changes from the open position shown in FIG. 1 to the closed position shown in FIG. automatically move to. The first on-off valve is configured as a solenoid valve, and is configured to assume a closed position when energized and an open position when not energized.

The first on-off valve 20 is controlled by a detector 34 that detects the vehicle speed and a control section 3 that determines a state on the verge of locking from the detected speed and sends a control signal to the first on-off valve.
6. That is, when the solenoid 38 of the first on-off valve is energized by a signal from the control section 36 in a state on the verge of locking, the spool 40 is attracted downward against the spring 42. Then, the upper spring 4 is released by the spool until now.
Poppet 4 was supported in the valve open position against 4.
6 is pressed against the valve seat 48 by the spring 44, and communication between the first oil passage 18 and the second oil passage 22 is cut off. That is, the hydraulic oil passage is closed.

Since the solenoid 38 is still energized, the spool 40 is further sucked downward even after the poppet 46 is seated, reaching the state shown in FIG. Then, the second oil passage 22 and the fourth oil passage 50, which have been blocked by the spool 40, are brought into communication. Therefore, the high pressure oil in the wheel cylinder 28 and the third oil passage 26 flows from the second oil passage 22 through both the second on-off valve 24 and the restriction orifice 32, which are still in the open position (the state shown in FIG. 1). 4 into the oil passage 50.

The hydraulic oil introduced into the fourth oil passage 50 is transferred to the check valve 52.
It is transmitted to the fifth oil passage 54 through the passage, and reaches a return pump 56 provided in the fifth oil passage. The hydraulic oil that has reached the return pump operates the pump piston 58 and is discharged by the pump piston again by the pump cam 60. The discharged hydraulic pressure does not flow backward through the check valve 52 on the upstream side of the return pump, but flows only in the direction shown by the arrow through the check valve 62 on the downstream side of the return pump, and reaches the sixth oil path 64.

The oil pressure that has reached the sixth oil passage 64 is transferred to the third on-off valve 66 and the seventh oil passage 68 which are in the open position as shown in FIG.
The oil is introduced into the oil chamber 70 of the second on-off valve 24 through.

The second on-off valve 24 includes a valve body 72, a spring 74 that biases the valve body in the closing direction, a mover 76, and a spring that pushes the mover 76 against the spring 74 and biases the valve body 72 to the open position. 7
It consists of 8.

Therefore, as described above, the seventh oil passage 68
The hydraulic pressure is transmitted to the oil chamber 7 of the second on-off valve.
0, it acts on the mover 76 forming the movable pressure receiving surface of the oil chamber, moving the mover to the right in the figure and separating it from the valve body 72. Therefore, the valve body 72 is pressed against the valve seat by the force of the spring 74 alone, and comes to the valve closing position shown in FIG.

As shown in the figure, the second on-off valve 24 is configured as a normally open type on-off valve that includes a check valve and a mover that biases the check valve to the open position. In the state shown in FIG. 3 in which the valve is moved to the release position, it functions as a simple check valve. Therefore, in the closed position of the second on-off valve, hydraulic pressure is freely transmitted from the third oil passage 26 to the second oil passage 22, but the opposite direction is blocked.

The seventh oil passage 68 is connected to the first oil passage 18 via a return check valve 80. The return check valve is a valve that allows flow only in the return direction, and is a valve that allows flow only in the return direction.
Only when the oil pressure in the first oil passage 18 becomes higher than the oil pressure in the first oil passage 18, the hydraulic oil is allowed to flow toward the master cylinder.

As is clear from the above explanation, the fourth oil passage 5
0, the fifth oil passage 54, the sixth oil passage 64, and the seventh oil passage 68 are provided in parallel with the hydraulic oil passage and constitute return oil passages that flow the hydraulic oil in the direction from the wheel cylinder to the master cylinder. It is.

As explained above, when the wheels reach a state on the verge of locking, the first on-off valve moves to the closed position shown in FIG. 2, closing the hydraulic oil passage, and the second oil passage 22 is communicated with the return oil passage. During this time, the braking oil pressure of the wheel cylinder 28 rapidly decreases.

When the oil pressure in the wheel cylinder decreases and the wheel is accelerated again, the energization to the solenoid 38 is automatically stopped, and the spool 40 of the first on-off valve 20 is moved upward by the force of the spring 42, and the poppet 46 upward to return the first on-off valve to the state shown in FIG. 1. In this way, when the hydraulic oil passage is communicated and the return oil passage is closed, the high oil pressure from the master cylinder 16 is again applied to the first oil passage 1.
8 into the second oil passage 22. However, in this case, unlike the state shown in FIG. 1, the second on-off valve 24 is closed as shown in FIG. It is maintained in the valve position and acts as a check valve. Therefore, the high oil pressure transmitted to the second oil passage 22 is transmitted to the third oil passage 26 only through the restriction orifice 32 and reaches the wheel cylinder 28. Therefore, unlike when braking is started, the oil pressure in the wheel cylinder increases slowly.

In this way, the wheel cylinder oil pressure increases slowly from the second time onwards, and when the wheel is on the verge of locking, the detector 34 detects this again and moves the first on-off valve 20 to the closed position shown in FIG. let me,
The high pressure oil in the wheel cylinder is returned from the fourth oil passage 50 and released to the oil passage to reduce the braking force. Since the oil pressure in the wheel cylinder 28 can also be released through the second on-off valve 24, which is a simple check valve, the oil pressure decreases rapidly even after the second time.

By repeating the rise and fall of the pressure in the wheel cylinder 28 as described above until the vehicle stops, skidding during braking is prevented.

In addition, the hydraulic oil discharged from the wheel cylinder to the return oil path after the first on-off valve 20 once reaches the closed position shown in Fig. 2 until it returns to the state shown in Fig. 1 is handled by the return pump. No. 6 oil passage 64 and No. 7
The hydraulic fluid in the master cylinder 16 does not continue to decrease and is successively replenished because it is sequentially sent to the master cylinder side via the oil passage 68 and the return check valve 80.

When braking is completed and the brake lever 14 is released, the oil pressure in the first oil passage 18 decreases and the seventh oil passage 68
Since the hydraulic pressure inside becomes relatively high, the hydraulic oil is sent to the master cylinder side through the return check valve 80, and the second on-off valve 24 is returned to the open position shown in FIG. 1, which is the state before braking. to return to.

As explained above, when braking is applied with the third on-off valve 66 in the open position (upper position) shown in FIG.
During the braking period, a predetermined oil pressure is maintained in the seventh oil passage 68 of the return oil passage, and this oil pressure acts on the oil chamber 70, so that the second on-off valve 24 remains in the closed position shown in FIG. Therefore, the second and subsequent oil pressures are supplied to the wheel cylinders 28 only through the limiting orifice 32, and therefore, the wheel cylinder oil pressure is always increased gradually from the second time onwards. In this case, the change in the wheel cylinder oil pressure becomes the state shown by the solid line A in FIG. In addition, in the example of FIG. 1, the first on-off valve 20 is provided on the upstream side and the second on-off valve 24 and the restriction orifice 32 are provided on the downstream side of the hydraulic oil path. It is also possible to provide the orifice on the upstream side.

Therefore, in the anti-skid device of the present invention, a third on-off valve 66 is provided at a position communicating with the oil chamber 70 through the seventh oil passage 68, and the third on-off valve 66 is operated as necessary. According to the seventh
The oil passage is configured to communicate with the open oil passage 82.

The third on-off valve 66 is configured as a solenoid valve, and includes a solenoid 84, a spool 86, a spring 88 that biases the spool to an upward position, a poppet 90 that opens and closes depending on the position of the spool, and a poppet that urges the poppet downward. It is equipped with a spring 92, and normally the spool 86 is moved by the force of the spring 88.
is located above and the poppet 90 is in the open position as shown in FIG. 1 to communicate between the sixth oil passage 64 and the seventh oil passage 68.
It cuts off the two.

When the solenoid 84 is energized and energized, the spool 86 is attracted downward and moved to the position shown in FIG. In this state, the poppet 90 is released from the spool 86 and is seated by the upper spring 92, blocking the sixth oil passage 64 and the seventh oil passage 68, and closing the seventh oil passage and the open oil passage 82.
communicate between. In the illustrated example, the open oil passage 82 is connected to the fourth oil passage 50 (return oil passage) via the spool 40 of the first on-off valve 20.

When the seventh oil passage 68 is communicated with the open oil passage 82,
The hydraulic pressure in the oil chamber 70 is released and the mover 76 is moved to the left by the force of the spring 78. Therefore, the second open valve 24 is moved from the closed position shown in FIG. 3 to the first open valve 24.
The valve can be switched to the open position shown in the figure. Then, even during the braking period, oil pressure is supplied to the wheel cylinder 28 through both the limiting orifice 32 and the second on-off valve 24, so the wheel cylinder oil pressure increases rapidly from the second time onward as well as at the beginning of braking. can be raised. Therefore, as shown in FIG. 6, any period t ₁ to
By operating the third on-off valve 66 at t ₂ and switching to the position shown in FIG. 4, the wheel cylinder 2
8, the oil pressure can rise and fall in the state shown by dotted line B.

Since the third on-off valve 66 can be operated arbitrarily,
The conditions from t ₁ to _{t 2} can be arbitrarily adjusted as necessary, and can be performed over the entire braking period or over multiple times.

FIG. 5 is a diagram showing the structure of the second on-off valve 124 used in another embodiment of the present invention. This embodiment differs only in that the second on-off valve 24 of the previous embodiment shown in FIGS. 1 to 4 is changed to the one shown in FIG. 5, and all other features are the same.

The second on-off valve in Figure 5 has two-position ON/OFF operation.
valve, and in its closed position, the second oil passage 22 and the third oil passage
Flow in both directions between the oil passages 26 can be blocked. That is, a valve body 126, a spring 128 that urges the valve body to the left in the figure, and a strong spring 130 that biases the valve body 126 to the illustrated open position against the spring 128 in the normal valve open state. It is equipped with a third on-off valve 6 during braking.
6 is in a state where the open oil passage 82 in FIG.
When the oil pressure in the oil passage 68 is acting on the oil chamber 70, the valve is opened, and when the third on-off valve is in the state of open oil passage communication as shown in FIG. 4 and the oil pressure in the seventh oil passage 68 is released. The valve is about to close. In this closed position, the valve becomes a complete stop valve, and the flow between the second oil passage 22 and the third oil passage 26 is blocked in both directions.

Therefore, according to the anti-skid device having the second on-off valve shown in FIG. 5, when the third on-off valve is not operated and is in the state shown in FIG. 1, the second on-off valve 124 is completely turned off. Since both the supply of hydraulic pressure to the wheel cylinder 28 and the release of hydraulic pressure from the wheel cylinder to the return oil passage are carried out only through the restriction orifice, the increase and decrease of the hydraulic pressure both occur slowly. Therefore,
In this case, the state of increase and decrease of the oil pressure is as shown by the solid line C in FIG. Therefore, the third on-off valve 6
6 and set it to the position shown in FIG.
When the hydraulic pressure of
It moves to the left and becomes the position shown in Figure 5.
The oil passage 22 and the third oil passage are brought into constant communication. In this state, hydraulic pressure is supplied to the wheel cylinders and hydraulic pressure is released from the wheel cylinders to the return oil path through both the restriction orifice 32 and the second on-off valve 24, so the rise and fall of the oil pressure is as shown in FIG. As shown by the dotted line D during the period t ₁ to _{t 2} , both can be performed rapidly.

The anti-skid device of the present invention has the configuration and operation described above, and in particular, it is provided with an open oil passage 82 that communicates with the oil chamber 70 of the second on-off valve 24 or 124, and the open oil passage is operated as necessary. Since the third on-off valve 66 is configured to open and close, even if the frictional resistance of the road surface changes during braking operation and it becomes necessary to suddenly increase the wheel cylinder oil pressure, the brake can be opened and closed accordingly. Braking can be adjusted. Therefore, even during braking, it is possible to freely control the increase in the hydraulic pressure in the wheel cylinders, or to speed up or slow down both the increase and decrease, as necessary, further improving safety and braking performance. be able to.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the overall structure of the anti-skid device of the present invention before braking, FIG. 2 is a partial sectional view showing the state of the first on-off valve in FIG. 3 is a partial sectional view showing the operating (valve closed) position of the second on-off valve in FIG. 1; FIG. 4 is a partial sectional view showing the operating position of the third on-off valve in FIG. 1; Fig. 5 is a partial sectional view showing a modified example of the second on-off valve, Fig. 6 is a chart showing changes in the wheel cylinder oil pressure of the anti-skid device shown in Fig. 1, and Fig. 7 is a partial cross-sectional view showing a modified example of the second on-off valve shown in Fig. 5. 3 is a chart showing changes in wheel cylinder oil pressure of the anti-skid device having the present invention. In each figure, the same reference numbers indicate the same or corresponding parts, 16...master cylinder, 1
8, 22, 26... Hydraulic oil passage (first, second and third oil passage), 20... First on-off valve, 24, 124...
...Second on-off valve, 28...Wheel cylinder, 30
...Auxiliary hydraulic oil passage, 32...Restriction orifice, 5
0, 54, 64, 68... Return oil path (4th, 5th, 6th and 7th oil path), 52, 62... Check valve, 56... Return pump, 66... Third on-off valve ,
70...Oil chamber, 80...Return check valve, 82...
Each shows an open oil passage.

Claims (1)

[Scope of Claims] 1. A hydraulic oil passage that supplies hydraulic pressure from a master cylinder to a wheel cylinder, a first on-off valve and a second on-off valve that are provided in series with each other in the middle of the hydraulic oil passage, and a master cylinder and a wheel cylinder. A return oil passage provided in parallel with the hydraulic oil passage between them, a return pump provided in the return oil passage, and a check valve provided on each of the upstream and downstream sides of the return pump to allow flow only in the return direction. , an auxiliary hydraulic oil passage that bypasses the second on-off valve, a restriction orifice provided in the auxiliary hydraulic oil passage, and a return oil passage provided in the return oil passage on the master cylinder side further from the check valve downstream of the return pump. a return check valve that allows flow only in the direction; an oil chamber to which hydraulic pressure is supplied between the check valve on the downstream side of the return pump and the return check valve; An anti-skid device for a vehicle braking device comprising a mover for holding a valve in a closed position, characterized in that an open oil passage communicating with the oil chamber is provided, and a third on-off valve is provided in the open oil passage. Anti skid device. 2. The anti-skid device according to item 1, wherein the second on-off valve is a normally open on-off valve having a check valve and a mover that biases the check valve to an open position. Device. 3. The anti-skid device according to item 1, wherein the second on-off valve is a two-position ON/OFF valve, and in its closed position, bidirectional flow is blocked. 4. The anti-skid device according to item 1, wherein the open oil passage is capable of communicating the oil chamber with the return oil passage upstream of the return pump.