초록 ▼

A brake apparatus includes multiple wheel cylinders; multiple maintaining valves; a pressure-regulating control valve; and a control unit that controls the upstream pressure by switching a pressure-control mode between a pressure-regulating mode which is selected when a deviation of the upstream pre

A brake apparatus includes multiple wheel cylinders; multiple maintaining valves; a pressure-regulating control valve; and a control unit that controls the upstream pressure by switching a pressure-control mode between a pressure-regulating mode which is selected when a deviation of the upstream pressure from a target pressure is outside a setting range and in which the upstream pressure is brought to the target pressure using the pressure-regulating control valve and a pressure-maintaining mode that is selected when the deviation is within the setting range. The control unit opens the pressure-regulating control valve before the pressure-control mode is switched from the pressure-maintaining mode to the pressure-regulating mode.

대표청구항 ▼

1. A brake apparatus, comprising: multiple wheel cylinders that apply braking forces to respective multiple wheels when being supplied with hydraulic fluid;multiple maintaining valves that are arranged upstream of the respective wheel cylinders in order to maintain hydraulic pressures in the respect

1. A brake apparatus, comprising: multiple wheel cylinders that apply braking forces to respective multiple wheels when being supplied with hydraulic fluid;multiple maintaining valves that are arranged upstream of the respective wheel cylinders in order to maintain hydraulic pressures in the respective wheel cylinders;pressure-regulating control valves that are arranged upstream of the multiple maintaining valves in order to control an upstream pressure which is a pressure upstream of the multiple maintaining valve, the pressure-regulating valves including a pressure-increasing linear control valve and a pressure-decreasing linear control valve; anda control unit that: calculates a deviation of the upstream pressure between a target upstream pressure and a measured upstream pressure,controls the braking forces by selecting one of multiple brake modes that include a regular brake mode in which all the maintaining valves are kept open so that the upstream pressure is supplied to the wheel cylinders and a special brake mode in which at least one of the maintaining valves is repeatedly opened and closed,controls the upstream pressure by switching a pressure-control mode to a pressure-regulating mode which is selected when the deviation of the upstream pressure is outside a setting range and in which the upstream pressure is brought to the target pressure by opening one of the pressure-increasing linear control valve or the pressure-decreasing linear control valve and closing the other of the pressure-increasing linear control valve or the pressure-decreasing linear control valve, andwhen the special brake mode is selected, controls the upstream pressure by switching to a pressure-maintaining mode that is selected when the deviation of the upstream pressure is within the setting range,wherein the control unit controls a valve opening pressure for opening the one of the pressure-increasing linear control valve or the pressure-decreasing linear control valve in the pressure-maintaining mode so that the one of the pressure-increasing linear control valve or the pressure-decreasing linear control valve is opened due to a differential pressure across the one of the pressure-regulating control valves before the pressure-control mode is switched from the pressure-maintaining mode to the pressure-regulating mode;wherein the control unit determines the setting range based on whether the pressure-regulating mode is a pressure-increase mode or a pressure-decrease mode, andwherein an upper limit of the setting range is a pressure-increase required threshold value and a lower limit of the setting range is a pressure-decrease required threshold value, the upper limit of the setting range for the pressure-increase mode in the regular brake mode being the same as the upper limit of the setting range for the pressure-increase mode in the special brake mode, andthe lower limit of the setting range for the pressure-decrease mode in the regular brake mode being less than the lower limit of the setting range for the pressure-decrease mode in the special brake mode. 2. The brake apparatus according to claim 1, wherein when the special brake mode is selected, the valve opening pressure is controlled in the pressure-maintaining mode in such a manner that the opened one of the pressure-increasing linear control valve or the pressure-decreasing linear control valve is opened when the upstream pressure is not within a permissible range that is included in the setting range and that includes the target pressure. 3. The brake apparatus according to claim 2, wherein: the pressure-increasing linear control valve is used to increase the upstream pressure and the pressure-decreasing linear control valve is used to decrease the upstream pressure; andthe control unit controls the valve opening pressure for opening the pressure-increasing linear control valve and the valve opening pressure for opening the pressure-decreasing linear control valve in such a manner that the pressure-increasing linear control valve is opened when the upstream pressure falls below the target pressure and the pressure-decreasing linear control valve is opened when the upstream pressure exceeds a reference pressure that is set to a value which is higher than the target pressure by a predetermined amount. 4. The brake apparatus according to claim 3, wherein: the pressure-decreasing linear control valve is an electromagnetically-controlled valve of which the valve opening pressure fluctuates in accordance with an electric current that is supplied to the pressure-decreasing linear control valve;the pressure-increasing linear control valve is an electromagnetically-controlled valve of which the valve opening pressure fluctuates in accordance with an electric current that is supplied to the pressure-increasing linear control valve; andthe control unit controls the valve opening pressure for opening the pressure-decreasing linear control valve by executing feedforward control over the electric current that is supplied to the pressure-decreasing linear control valve, or the valve opening pressure for opening the pressure-increasing linear control valve by executing feedforward control over the electric current that is supplied to the pressure-increasing linear control valve. 5. The brake apparatus according to claim 1, wherein: the control unit controls the valve opening pressure for opening the pressure-increasing linear control valve in such a manner that the pressure-increasing linear control valve is opened when the upstream pressure falls below the target pressure in the pressure-regulating mode. 6. A brake apparatus, comprising: multiple wheel cylinders that apply braking forces to respective multiple wheels when being supplied with hydraulic fluid;multiple maintaining valves that are arranged upstream of the respective wheel cylinders in order to maintain hydraulic pressures in the respective wheel cylinders;pressure-regulating control valves that are arranged upstream of the multiple maintaining valves in order to control an upstream pressure which is a pressure upstream of the multiple maintaining valves, the pressure-regulating valves including a pressure-increasing linear control valve and a pressure-decreasing linear control valve; anda control unit that: calculates a deviation of the upstream pressure between a target upstream pressure and a measured upstream pressure,controls the braking forces by selecting one of multiple brake modes that include a regular brake mode in which all the maintaining valves are kept open so that the upstream pressure is supplied to the wheel cylinders and a special brake mode in which at least one of the maintaining valves is repeatedly opened and closed,controls the upstream pressure by switching a pressure-control mode to a pressure-regulating mode which is selected when the deviation of the upstream pressure is outside a setting range and in which the upstream pressure is controlled by opening one of the pressure-increasing linear control valve or the pressure-decreasing linear control valve and closing the other of the pressure-increasing linear control valve or the pressure-decreasing linear control valve, andwhen the special brake mode is selected, controls the upstream pressure by switching to a pressure-maintaining mode that is selected when the deviation of the upstream pressure is within the setting range,wherein the control unit opens one of the pressure-increasing linear control valve or the pressure-decreasing linear control valve before the pressure-control mode is switched from the pressure-maintaining mode to the pressure-regulating mode,wherein the control unit determines the setting range based on whether the pressure-regulating mode is a pressure-increase mode or a pressure-decrease mode, andwherein an upper limit of the setting range is a pressure-increase required threshold value and a lower limit of the setting range is a pressure-decrease required threshold value, the upper limit of the setting range for the pressure-increase mode in the regular brake mode being the same as the upper limit of the setting range for the pressure-increase mode in the special brake mode, andthe lower limit of the setting range for the pressure-decrease mode in the regular brake mode being less than the lower limit of the setting range for the pressure-decrease mode in the special brake mode. 7. The brake apparatus according to claim 6, wherein when the special brake mode is selected, the control unit opens one of the pressure-increasing linear control valve or the pressure-decreasing linear control valve when the upstream pressure is not within a permissible range that is included in the setting range and that includes the target pressure. 8. The brake apparatus according to claim 7, wherein: the pressure-increasing linear control valve is used to increase the upstream pressure and the pressure-decreasing linear control valve is used to decrease the upstream pressure; andthe control unit opens the pressure-increasing linear control valve when the upstream pressure falls below the target pressure, and opens the pressure-decreasing linear control valve when the upstream pressure exceeds a reference pressure that is set to a value which is higher than the target pressure by a predetermined amount. 9. The brake apparatus according to claim 8, wherein: the pressure-decreasing linear control valve is an electromagnetically-controlled valve of which the valve opening pressure fluctuates in accordance with an electric current that is supplied to the pressure-decreasing linear control valve;the pressure-increasing linear control valve is an electromagnetically-controlled valve of which the valve opening pressure fluctuates in accordance with an electric current that is supplied to the pressure-increasing linear control valve; andthe control unit opens the pressure-decreasing linear control valve by executing feedforward control over the electric current that is supplied to the pressure-decreasing linear control valve, or opens the pressure-increasing linear control valve by executing feedforward control over the electric current that is supplied to the pressure-increasing linear control valve. 10. The brake apparatus according to claim 6, wherein the control unit opens the pressure-increasing linear control valve when the upstream pressure falls below the target pressure in the pressure-regulating mode. 11. A method for controlling a brake apparatus which includes multiple wheel cylinders that apply braking forces to respective multiple wheels when being supplied with hydraulic fluid; multiple maintaining valves that are arranged upstream of the respective wheel cylinders in order to maintain hydraulic pressures in the respective wheel cylinders; and pressure-regulating control valves, including a pressure-increasing linear control valve and a pressure-decreasing linear control valve, that are arranged upstream of the multiple maintaining valves in order to control an upstream pressure which is a pressure upstream of the multiple maintaining valves, the method comprising: calculating a deviation of the upstream pressure between a target upstream pressure and a measured upstream pressure;selecting one of multiple brake modes that include a regular brake mode in which all the maintaining valves are kept open so that the upstream pressure is supplied to the wheel cylinders and a special brake mode in which at least one of the maintaining valves is repeatedly opened and closed;selecting a pressure-regulating mode in which the upstream pressure is controlled by opening one of the pressure-increasing linear control valve or the pressure-decreasing linear control valve and closing the other of the pressure-increasing linear control valve or the pressure-decreasing linear control valve, when the deviation of the upstream pressure is outside a setting range;selecting a pressure-maintaining mode when the special brake mode is selected and the deviation is within the setting range; andopening one of the pressure-increasing linear control valve or the pressure-decreasing linear control valve before the pressure-control mode is switched from the pressure-maintaining mode to the pressure-regulating mode,wherein the setting range is determined based on whether the pressure-regulating mode is a pressure-increase mode or a pressure-decrease mode, andwherein an upper limit of the setting range is a pressure-increase required threshold value and a lower limit of the setting range is a pressure-decrease required threshold value, the upper limit of the setting range for the pressure-increase mode in the regular brake mode being the same as the upper limit of the setting range for the pressure-increase mode in the special brake mode, andthe lower limit of the setting range for the pressure-decrease mode in the regular brake mode being less than the lower limit of the setting range for the pressure-decrease mode in the special brake mode. 12. The method according to claim 11, wherein: when the special brake mode is selected, one of the pressure-increasing linear control valve or the pressure-decreasing linear control valve is opened when the upstream pressure is not within a permissible range that is included in the setting range and that includes the target pressure. 13. The method according to claim 12, wherein the pressure-increasing linear control valve is used to increase the upstream pressure and the pressure-decreasing linear control valve is used to decrease the upstream pressure;the pressure-increasing linear control valve is opened when the upstream pressure falls below the target pressure; andthe pressure-decreasing linear control valve is opened when the upstream pressure exceeds a reference pressure that is set to a value which is higher than the target pressure by a predetermined amount. 14. The method according to claim 13, wherein the pressure-decreasing linear control valve is an electromagnetically-controlled valve of which the valve opening pressure fluctuates in accordance with an electric current that is supplied to the pressure-decreasing linear control valve;the pressure-increasing linear control valve is an electromagnetically-controlled valve of which the valve opening pressure fluctuates in accordance with an electric current that is supplied to the pressure-increasing linear control valve; andfeedforward control is executed over the electric current that is supplied to the pressure-decreasing linear control valve so that the pressure-decreasing linear control valve is opened, or feedforward control is executed over the electric current that is supplied to the pressure-increasing linear control valve so that the pressure-increasing linear control valve is opened. 15. The method according to claim 11, wherein the pressure-increasing linear control valve is opened when the upstream pressure falls below the target pressure in the pressure-regulating mode.