| 摘要 |
A brake fluid pressure retaining unit is provided which allows a relief pressure to be variable only by use of a low-cost electromagnetic valve without using an expensive relief valve and orifice. The brake fluid pressure retaining unit includes an electromagnetic valve which is provided midway in a brake fluid channel connecting a master cylinder and a wheel cylinder and is capable of freely opening/closing the brake fluid channel by passing current though a solenoid coil; and an electromagnetic valve control section which detects a release signal indicative of releasing brake operation detected by a brake operation detecting section and passes current through the solenoid coil while referring to current values corresponding to a target maintaining fluid pressure to maintain a predetermined braking force. The electromagnetic valve control section determines in advance a predetermined opening-side current value required to switch the electromagnetic valve from a closed state to an open state and a predetermined closing-side current value required to switch the electromagnetic valve from an open state to a closed state, for each target maintaining fluid pressure, and performs control so that the value of the current to be passed through the solenoid coil is in a range between the predetermined opening-side current value and predetermined closing-side current value.
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