BRAKE APPARATUS AND BRAKE METHOD

Abstract

Disclosed herein are a brake system and a method therefor. The brake system is used in a negative brake system and includes a service brake line through which a pressure is supplied to or recovered from a service brake for application or release of a braking force thereto or therefrom, a parking brake line through which a pressure is supplied to or recovered from a parking brake for application or release of a braking force thereto or therefrom, and a control unit configured to detect whether or not a driver operates the service brake to control the recovery of the pressure in the parking brake line when an abnormality occurs in the service brake line.

Claims

1. A brake system used in a negative brake system, comprising: a service brake line through which a pressure is supplied to or recovered from a service brake for application or release of a braking force thereto or therefrom; a parking brake line through which a pressure is supplied to or recovered from a parking brake for application or release of a braking force thereto or therefrom; and a control unit configured to detect whether or not a driver operates the service brake to control the recovery of the pressure in the parking brake line when an abnormality occurs in the service brake line.

2. The brake system according to claim 1, wherein the detection of whether or not the service brake is operated is performed by a sensor for detecting whether or not a service brake pedal moves down.

3. The brake system according to claim 1, wherein the detection of whether or not the service brake is operated is performed by a sensor for detecting whether or not to move a piston of a service brake pressure supply device.

4. The brake system according to claim 1, wherein the control unit operates a valve on the parking brake line to control the recovery of the pressure in the parking brake line.

5. The brake system according to claim 4, wherein the valve is a proportional valve.

6. The brake system according to claim 4, wherein the control unit recovers the pressure in the parking brake line by a predetermined pressure per hour.

7. The brake system according to claim 1, wherein the control unit is a transmission electronic control unit.

8. The brake system according to claim 1, wherein the service brake line comprises: a first service brake line through which a pressure is supplied to or recovered from the service brake for application or release of the braking force thereto or therefrom; and a second service brake line connected to a first chamber of one of brake discs to supply a pressure to the first chamber, and the parking brake line comprises: a first parking brake line through which a pressure is supplied to or recovered from the parking brake for application or release of the braking force thereto or therefrom; and a second parking brake line connected to a second chamber of the other of the brake discs to supply a pressure to the second chamber.

9. The brake system according to claim 8, further comprising a parking release valve switchable between a first state, in which the first service brake line communicates with the second service brake line and the first parking brake line communicates with the second parking brake line, and a second state in which the first service brake line communicates with the second parking brake line.

10. The brake system according to claim 9, wherein the first parking brake line is disconnected from the second service brake line in the second state.

11. The brake system according to claim 9, wherein, in the second state to which the parking release valve switches, the parking brake is released by the pressure supplied through the first service brake line and the second parking brake line.

12. A braking method comprising: detecting an abnormality of a service brake line of a vehicle in a negative brake system; and stopping the vehicle with a parking brake when the abnormality of the service brake line is detected, wherein the stopping the vehicle is performed by detecting whether or not a driver operates a service brake to control recovery of a pressure in a parking brake line.

13. The braking method according to claim 12, wherein the detection of whether or not the service brake is operated is performed by a sensor for detecting whether or not a service brake pedal moves down.

14. The braking method according to claim 12, wherein the detection of whether or not the service brake is operated is performed by a sensor for detecting whether or not to move a piston of a service brake pressure supply device.

15. The braking method according to claim 12, wherein a valve on the parking brake line is operated to control the recovery of the pressure in the parking brake line.

16. The braking method according to claim 15, wherein the valve is a proportional valve.

17. The braking method according to claim 15, wherein the pressure in the parking brake line is controlled to be recovered by a predetermined pressure per hour.

18. The braking method according to claim 12, wherein the controlling recovery of a pressure is performed by a transmission electronic control unit.

19. The braking method according to claim 12, wherein the service brake line comprises: a first service brake line through which a pressure is supplied to or recovered from the service brake for application or release of a braking force thereto or therefrom; and a second service brake line connected to a first chamber of one of brake discs to supply a pressure to the first chamber, and the parking brake line comprises: a first parking brake line through which a pressure is supplied to or recovered from the parking brake for application or release of a braking force thereto or therefrom; and a second parking brake line connected to a second chamber of the other of the brake discs to supply a pressure to the second chamber.

20. The braking method according to claim 19, wherein a first state, in which the first service brake line communicates with the second service brake line and the first parking brake line communicates with the second parking brake line, and a second state, in which the first service brake line communicates with the second parking brake line, are switchable therebetween.

21. The braking method according to claim 20, wherein the first parking brake line is disconnected from the second service brake line in the second state.

22. The braking method according to claim 20, wherein, in the second state, the parking brake is released by the pressure supplied through the first service brake line and the second parking brake line.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0036] FIG. 1 is a diagram illustrating a state in which a brake system according to an embodiment of the present invention is normally operated.

[0037] FIG. 2 is a diagram illustrating a first emergency situation, such as a situation where a vehicle stalls, a situation where an engine is abnormally stopped, a situation where an abnormality occurs in an electric system, or a situation where an abnormality occurs in a hydraulic or pneumatic system of a parking brake, in the brake system according to the embodiment of the present invention.

[0038] FIG. 3 is a diagram illustrating a second emergency, such as a situation where an abnormality occurs in a hydraulic or pneumatic system of a service brake in the brake system according to the embodiment of the present invention.

[0039] FIG. 4 is a diagram illustrating a state in which service brake lines are abnormal in a brake assembly according to the embodiment of the present invention.

[0040] FIG. 5 is a diagram illustrating a normal state in the brake assembly according to the embodiment of the present invention.

[0041] FIG. 6 is a diagram illustrating a brake system according to another embodiment of the present invention.

BEST MODE FOR INVENTION

[0042] Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings.

[0043] In certain embodiments, detailed descriptions of technology well known in the art may be omitted to avoid obscuring appreciation of the disclosure by a person of ordinary skill in the art. In addition, the terms used in the specification are terms defined in consideration of functions of the present invention, and these terms may vary with the intention or practice of a user or an operator. Therefore, these terms should be defined based on the entire content disclosed herein.

[0044] It will be understood that the present disclosure is defined only by the claims. These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0045] Hereinafter, the configuration and operation of a brake system, in each case of normal operation, parking brake line breakage or engine stop, and service brake line breakage, according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0046] In the following description, the pressure supplied for application and release of a braking force may be a fluid pressure, in which case the fluid pressure may be an oil or air pressure. Hereinafter, the term supply of pressure means the supply of the oil or air pressure.

[0047] First, as illustrated in FIG. 1, the brake system according to the embodiment of the present invention is a system that is used in a negative brake system, and may include a first service brake line 10 through which a pressure may be supplied to or recovered from a service brake for application or release of a braking force thereto or therefrom, and a first parking brake line 30 through which a pressure may be supplied to or recovered from a parking brake for application or release of a braking force thereto or therefrom. In addition, the brake system may include a second service brake line 20 that is connected to a first chamber 120 of one of brake discs 110 located within a brake assembly 100 to supply a pressure to the first chamber 120, and a second parking brake line 40 that is connected to a second chamber 130 of the other of the brake discs 110 to supply a pressure to the second chamber 130. Here, the respective first and second chambers 120 and 130 may include therein chamber blocks 122 and 132 and elastic means 124 and 134 for elastically supporting the respective chamber blocks 122 and 132. When the pressure is supplied to the first chamber 120, the braking force is applied to the brake by the chamber block 122 against the support force of the elastic means 124. When the pressure is recovered from the first chamber 120, the brake may be released by the restoring force of the elastic means 124. When the pressure is supplied to the second chamber 130 in a state in which the chamber block 132 is elastically supported to apply the braking force to the brake, the brake may be released by the chamber block 132 against the support force of the elastic means 134.

[0048] Furthermore, the brake system according to the embodiment of the present invention may include a parking release valve 200. The parking release valve 200 may switch between a first state (see FIG. 1), in which the first service brake line 10 communicates with the second service brake line 20 and the first parking brake line 30 communicates with the second parking brake line 40, and a second state (see FIG. 2) in which the first service brake line 10 communicates with the second parking brake line 40. Meanwhile, a separate check valve (not shown) may be provided on the first parking brake line 30 to control the supply of pressure to the first parking brake line 30.

[0049] Next, the brake system, in each case when the vehicle is stalled or parked and stopped and when the vehicle travels, according to the embodiment of the present invention will be described in more detail with reference to FIGS. 1 and 2.

[0050] First, as illustrated in FIGS. 1 and 2, the brake system according to the embodiment of the present invention may include the first service brake line 10 through which the pressure may be supplied to or recovered from the service brake for application or release of the braking force thereto or therefrom, the first parking brake line 30 through which the pressure may be supplied to or recovered from the parking brake for application or release of the braking force thereto or therefrom, the second service brake line 20 that is connected to the first chamber 120 of one of the brake discs 110 to supply the pressure to the first chamber 120, and the second parking brake line 40 that is connected to the second chamber 130 of the other of the brake discs 110 to supply the pressure to the second chamber 130.

[0051] The brake system according to the embodiment of the present invention enables the vehicle to be manually or automatically parked through the above configuration.

[0052] FIG. 1 is a diagram illustrating a state in which the brake system is normally operated.

[0053] As illustrated in FIG. 1, when the vehicle is stalled or parked and stopped, a valve 32 provided on the first parking brake line 30 is in an off state. In this case, since the fluid in the second chamber 130 of the brake assembly 100 is discharged through the second and first parking brake lines 40 and 30 due to the characteristics of the negative brake system, the brake discs 110 come into contact with each other with the consequence that the braking force is applied to the parking brake.

[0054] In addition, the first service brake line 10 is connected to a brake pedal 12, and a service brake pressure supply device 14 is provided on a path therebetween.

[0055] As such, since the braking force is applied to the parking brake when the vehicle is stalled or parked and stopped, the vehicle is not moved.

[0056] Next, when the vehicle travels, the valve 32 provided on the first parking brake line 30 may be turned on. In this case, a pressure is supplied into the second chamber 130 of the brake assembly 100 through the second parking brake line 40 from the first parking brake line 30. By supply of the pressure, the brake discs 110 are separated from each other with the consequence that the braking force of the parking brake is released.

[0057] In addition, the first service brake line 10 is connected to the brake pedal 12, and the service brake pressure supply device 14 is provided on the path therebetween. When a pressure is supplied into the first chamber 120 of the brake assembly 100 from the service brake pressure supply device 14 by pressing the brake pedal 12 by a driver, the brake discs 110 come into contact with each other with the consequence that the braking force is applied to the service brake. On the other hand, when the pressing of the brake pedal 12 by the driver is released, the fluid in the first chamber 120 of the brake assembly 100 is discharged through the second and first service brake lines 20 and 10. Thus, the brake discs 110 are separated from each other with the consequence that the braking force of the service brake is released. That is, the brake discs 110 may come into contact with or be separated from each other according to whether or not the driver presses the brake pedal 12.

[0058] As such, the braking force of the parking brake is released when the vehicle travels. Accordingly, the braking force is applied to or released from the service brake according to whether or not to press the brake pedal 12.

[0059] As described above, the vehicle is in the normal state when it is stalled or parked and stopped and when it travels. In this case, the parking release valve 200 according to the embodiment of the present invention is in the first state, namely in the state in which the first service brake line 10 communicates with the second service brake line 20 and the first parking brake line 30 communicates with the second parking brake line 40.

[0060] Next, FIG. 2 is a diagram illustrating a first emergency situation, such as a situation where a vehicle stalls, a situation where an engine is abnormally stopped, a situation where an abnormality occurs in an electric system, or a situation where an abnormality occurs in a hydraulic or pneumatic system of the parking brake.

[0061] As illustrated in FIG. 2, when the vehicle is in the first emergency situation, the supply of pressure to the first parking brake line 30 is stopped in the vehicle. Accordingly, the fluid in the second chamber 130 of the brake assembly 100 is discharged through the second and first parking brake lines 40 and 30. Thus, the brake discs 110 come into contact with each other with the consequence that the braking force is applied to the parking brake. Meanwhile, the valve 32 provided on the first parking brake line 30 is illustrated to be in an off state for easy description of the above state.

[0062] Similarly, the first service brake line 10 is connected to the brake pedal 12, and the service brake pressure supply device 14 is provided on the path therebetween.

[0063] As such, since the braking force is applied to the parking brake in the emergency situation, the vehicle is not moved.

[0064] In this state, when the parking release valve 200, which is in the first state, switches to the second state in which the first service brake line 10 communicates with the second parking brake line 40, namely when the parking release valve 200 moves to a second position (indicated by the solid line in FIG. 2) such that a spool is in the second state, the braking force applied to the parking brake may be released.

[0065] Consequently, a pressure is supplied to the second chamber 130 of the other of the brake discs 110 connected to the second parking brake line 40, thereby enabling the braking force of the parking brake to be released.

[0066] In this emergency situation, the first parking brake line 30 may be disconnected from the second service brake line 20. However, in the brake system according to the embodiment of the present invention, a pressure is supplied through the first service brake line 10 and the second parking brake line 40 in order to release the braking force of the parking brake in the emergency situation, and no pressure is supplied through the first parking brake line 30. Therefore, the first parking brake line 30 may also communicate with the second service brake line 20.

[0067] FIG. 3 is a diagram illustrating a second emergency situation, such as a situation where an abnormality occurs in a hydraulic or pneumatic system of the service brake.

[0068] Referring to FIG. 3, when an abnormality occurs in the service brake lines 10 and 20, the recovery of pressure in the parking brake lines 30 and 40 is controlled by detecting whether or not the driver operates the service brake. Thus, the parking brake may substitute for the role of the service brake. The detection of whether or not the driver operates the service brake may be performed by a sensor 16 that detects whether or not the service brake pedal 12 moves down. The sensor 16 may be a switch that is positioned beneath the service brake pedal 12. When the driver presses the service brake pedal 12, the service brake pedal 12a may move down to come into contact with the sensor 16. Through such a structure, the sensor 16 may detect the downward movement of the service brake pedal 12.

[0069] When the sensor 16 detects the downward movement of the service brake pedal 12, a detection signal may be transmitted to a control unit 50 through a first control line 60 connected to the sensor 16. The control unit 50 may be a transmission electronic control unit (TECU). When the detection signal is transmitted to the control unit 50, the control unit 50 may operate the valve 32 disposed on the first parking brake line 30 through a second control line 70 to control the recovery of pressure in the parking brake lines 30 and 40. In order to slowly recover the pressure in the parking brake lines 30 and 40, the valve 32 may be a proportional valve. Since the proportional valve is used as the valve 32, the valve 32 enables the pressure in the parking brake lines to be slowly recovered by a predetermined pressure per hour.

[0070] FIG. 4 is a diagram illustrating a state of the brake assembly 100 when the service brake lines are abnormal.

[0071] Referring to FIG. 4, when an abnormality occurs in the service brake lines, the first chamber 120 in the brake assembly 100 is not operated. However, in the brake system according to the embodiment of the present invention, when the driver presses the service brake pedal, the pressure in the parking brake lines 30 and 40 may be recovered by the control unit 50 so that the second chamber 130 is operated. That is, it is possible to reduce the pressure for the second chamber block 132 against the support force of the second elastic means 134 by recovering the pressure in the parking brake lines 30 and 40. Then, the second chamber block 132 may come into contact with the brake discs 110 by the support force of the second elastic means 134, to thereby apply braking to the vehicle. However, since the pressure in the parking brake lines 30 and 40 is slowly recovered by the valve 32 as described above, the braking of the vehicle may be performed smoothly rather than suddenly.

[0072] FIG. 5 is a diagram illustrating the brake assembly 100 in a normal state.

[0073] Referring to FIG. 5, when the driver presses the service brake pedal in the normal state, the pressure in the service brake lines 10 and 20 may be recovered so that the first chamber is operated. That is, it is possible to reduce the pressure for the first chamber block 122 against the support force of the first elastic means 124 by recovering the pressure in the service brake lines 10 and 20. Then, the first chamber block 122 may come into contact with the brake discs 110 by the support force of the first elastic means 124, to thereby apply braking to the vehicle.

[0074] FIG. 6 is a diagram illustrating a brake system according to another embodiment of the present invention. The description of the same configuration as the above-mentioned embodiment will be omitted.

[0075] Referring to FIG. 6, a sensor 18 for detecting whether or not the service brake is operated may be positioned at the service brake pressure supply device 14. In more detail, the sensor 18 may be installed to detect movement of a piston in the service brake pressure supply device 14. When the driver presses the service brake pedal 12, the piston in the service brake pressure supply device 14 may move. Accordingly, the detection of the movement of the piston in the service brake pressure supply device 14 by the sensor 18 may correspond to detecting the operation of the service brake by the driver. When the sensor 18 detects the movement of the piston in the service brake pressure supply device 14, the detected result may be transmitted to the control unit 50 through the first control line 60. The subsequent operations may be identical to those in the above-mentioned embodiment.

[0076] Although the present invention has been described with respect to the illustrative embodiments, it will be apparent to those skilled in the art that various variations and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.

DESCRIPTION OF REFERENCE NUMERALS

[0077] 10: first service brake line [0078] 12: service brake pedal [0079] 14: service brake pressure supply device [0080] 16, 18: sensor [0081] 20: second service brake line [0082] 30: first parking brake line [0083] 32: valve [0084] 40: second parking brake line [0085] 50: control unit [0086] 60: first control line [0087] 70: second control line [0088] 100: brake assembly [0089] 110: brake disc [0090] 120: first chamber [0091] 122: first chamber block [0092] 124: first elastic means [0093] 130: second chamber [0094] 132: second chamber block [0095] 134: second elastic means [0096] 200: parking release valve