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US-20260125040-A1 - HYDRAULIC PRESSURE CONTROL UNIT, BRAKE SYSTEM, AND DIAGNOSIS METHOD

US20260125040A1US 20260125040 A1US20260125040 A1US 20260125040A1US-20260125040-A1

Abstract

[Problem] The present invention obtains a hydraulic pressure control unit, a brake system, and a diagnosis method capable of appropriately diagnosing an abnormality of a power supply line. [Means for Resolution] A hydraulic pressure control unit ( 5 ) includes: a hydraulic pressure control mechanism including an inlet valve ( 31 ) as an electromagnetic valve that is electrically connected to a power supply ( 7 ) through a power supply line ( 8 ), a control device ( 52 ) that controls an operation of the hydraulic pressure control mechanism, and a resistance ( 35 ) that is electrically connected to the power supply ( 7 ) through the power supply line ( 8 ), in which a diagnosis unit of the control device ( 52 ) performs a power supply line diagnosis in which an abnormality of the power supply line ( 8 ) is diagnosed, in a state where no current is applied to the inlet valve ( 31 ) but a current is applied to the resistance ( 35 ), based on a voltage change in the power supply line ( 8 ) when the current to be applied to the resistance ( 35 ) is changed.

Inventors

  • Shohei ISHII

Assignees

  • ROBERT BOSCH GMBH

Dates

Publication Date
20260507
Application Date
20231009
Priority Date
20221012

Claims (8)

  1. 1 . A hydraulic pressure control unit ( 5 ) that is used in a brake system ( 10 ) of a straddle-type vehicle ( 100 ), the hydraulic pressure control unit comprising: a hydraulic pressure control mechanism ( 51 ) including an inlet valve ( 31 ) as an electromagnetic valve that is electrically connected to a power supply ( 7 ) through a power supply line ( 8 ), that is provided to a flow path ( 25 ) that communicates with a master cylinder ( 21 ) and a wheel cylinder ( 24 ), and that has an open state in no-energization and has a closed state in energization; and a control device ( 52 ) that controls an operation of the hydraulic pressure control mechanism ( 51 ), and further comprising a resistance ( 35 ) that is electrically connected to the power supply ( 7 ) through the power supply line ( 8 ), wherein the control device ( 52 ) includes a diagnosis unit ( 52 c ) that performs a power supply line diagnosis in which an abnormality of the power supply line ( 8 ) is diagnosed, in a state where no current is applied to the inlet valve ( 31 ) but a current is applied to the resistance ( 35 ), based on a voltage change in the power supply line ( 8 ) when the current to be applied to the resistance ( 35 ) is changed.
  2. 2 . The hydraulic pressure control unit according to claim 1 , the hydraulic pressure control unit further comprising: a first line (L 1 ) to which the inlet valve ( 31 ) is provided and a second line (L 2 ) to which the resistance ( 35 ) is provided, which are electrically connected to each other in parallel; and a switching unit (SW 1 , SW 2 , SW 3 ) that switches a path of the current in the hydraulic pressure control unit ( 5 ), wherein the diagnosis unit ( 52 c ) switches the path by the switching unit (SW 1 , SW 2 , SW 3 ) in the power supply line diagnosis such that no current flows in the first line (L 1 ) but the current flows in the second line (L 2 ).
  3. 3 . The hydraulic pressure control unit according to claim 2 , wherein the control device ( 52 ) includes an integrated circuit ( 521 ), a downstream end of the first line (L 1 ) and a downstream end of the second line (L 2 ) are both connected to the integrated circuit ( 521 ), and the switching unit (SW 1 , SW 2 , SW 3 ) includes a first switching element (SW 1 ) that is electrically connected to the downstream end of the first line (L 1 ), and is incorporated in the integrated circuit ( 521 ), and a second switching element (SW 2 ) that is electrically connected to the downstream end of the second line (L 2 ), and is incorporated in the integrated circuit ( 521 ).
  4. 4 . The hydraulic pressure control unit according to claim 2 , the hydraulic pressure control unit further comprising a third line (L 3 ) that electrically connects a merging portion (P 1 ) of an upstream side of the first line (L 1 ) and an upstream side of the second line (L 2 ), to the power supply line ( 8 ), wherein the switching unit (SW 1 , SW 2 , SW 3 ) includes a third switching element (SW 3 ) that is provided to the third line (L 3 ).
  5. 5 . The hydraulic pressure control unit according to claim 4 , wherein the diagnosis unit ( 52 c ) performs the power supply line diagnosis when it is determined that a voltage at the power supply line ( 8 ) side relative to the third switching element (SW 3 ) in the third line (L 3 ) is stable.
  6. 6 . The hydraulic pressure control unit according to claim 4 , wherein the diagnosis unit ( 52 c ) performs the power supply line diagnosis in a state where the third switching element (SW 3 ) is closed, and acquires a voltage of the power supply line ( 8 ), based on a voltage at the merging portion (P 1 ) side relative to the third switching element (SW 3 ) in the third line (L 3 ), in the power supply line diagnosis.
  7. 7 . A brake system comprising the hydraulic pressure control unit ( 5 ) according to claim 1 , wherein the number of the wheel cylinders ( 24 ) that communicate with the one master cylinder ( 21 ) is one.
  8. 8 . A diagnosis method of a hydraulic pressure control unit ( 5 ) that is used in a brake system ( 10 ) of a straddle-type vehicle ( 100 ), the hydraulic pressure control unit ( 5 ) including: a hydraulic pressure control mechanism ( 51 ) including an inlet valve ( 31 ) as an electromagnetic valve that is electrically connected to a power supply ( 7 ) through a power supply line ( 8 ), that is provided to a flow path ( 25 ) that communicates with a master cylinder ( 21 ) and a wheel cylinder ( 24 ), and that has an open state in no-energization and has a closed state in energization; and a control device ( 52 ) that controls an operation of the hydraulic pressure control mechanism ( 51 ), and further including a resistance ( 35 ) that is electrically connected to the power supply ( 7 ) through the power supply line ( 8 ), the diagnosis method comprising performing, by a diagnosis unit ( 52 c ) of the control device ( 52 ), a power supply line diagnosis in which an abnormality of the power supply line ( 8 ) is diagnosed, in a state where no current is applied to the inlet valve ( 31 ) but a current is applied to the resistance ( 35 ), based on a voltage change in the power supply line ( 8 ) when the current to be applied to the resistance ( 35 ) is changed.

Description

BACKGROUND The present disclosure relates to a hydraulic pressure control unit, a brake system, and a diagnosis method capable of appropriately diagnosing an abnormality of a power supply line. A hydraulic pressure control unit for controlling a braking force to be generated in wheels is provided in a straddle-type vehicle (for example, see JP2018-8674A). In the hydraulic pressure control unit, a hydraulic pressure control mechanism including an electromagnetic valve controls the hydraulic pressure of a brake fluid. A hydraulic pressure control unit is electrically connected to a power supply through a power supply line such as a wire harness. Each device such as the electromagnetic valve in the hydraulic pressure control unit operates using electric power that is supplied from the power supply through the power supply line. When an abnormality of the power supply line (for example, aged deterioration) is generated to make a resistance value of the power supply line excessively large, it becomes difficult to operate the hydraulic pressure control unit normally. Therefore, a power supply line diagnosis in which an abnormality of the power supply line is diagnosed is performed. In the power supply line diagnosis, for example, an inlet valve to be provided in a flow path that communicates with a master cylinder and a wheel cylinder is opened and closed, and an abnormality of the power supply line is diagnosed based on a voltage change in the power supply line in that case. Therefore, in a case where a brake operation is performed by a rider during the execution of the power supply line diagnosis, it can be difficult to brake the straddle-type vehicle with the intention of the rider. Therefore, it is desired to appropriately diagnose an abnormality of the power supply line by suppressing such a situation. SUMMARY The present invention is made in view of the abovementioned problems, and obtains a hydraulic pressure control unit, a brake system, and a diagnosis method capable of appropriately diagnosing an abnormality of a power supply line. A hydraulic pressure control unit according to the invention is a hydraulic pressure control unit that is used in a brake system of a straddle-type vehicle, the hydraulic pressure control unit includes: a hydraulic pressure control mechanism including an inlet valve as an electromagnetic valve that is electrically connected to a power supply through a power supply line, is provided to a flow path that communicates with a master cylinder and a wheel cylinder, and becomes an open state in no-energization and becomes a closed state in energization; and a control device that controls an operation of the hydraulic pressure control mechanism, and further includes a resistance that is electrically connected to the power supply through the power supply line, in which the control device includes a diagnosis unit that performs a power supply line diagnosis in which an abnormality of the power supply line is diagnosed, in a state where no current is applied to the inlet valve but a current is applied to the resistance, based on a voltage change in the power supply line when the current to be applied to the resistance is changed. A brake system according to the invention includes the abovementioned hydraulic pressure control unit, in which the number of the wheel cylinders that communicate with the one master cylinder is one. A diagnosis method according to the invention is a diagnosis method of a hydraulic pressure control unit that is used in a brake system of a straddle-type vehicle, the hydraulic pressure control unit including: a hydraulic pressure control mechanism including an inlet valve as an electromagnetic valve that is electrically connected to a power supply through a power supply line, is provided to a flow path that communicates with a master cylinder and a wheel cylinder, and becomes an open state in no-energization and becomes a closed state in energization; and a control device that controls an operation of the hydraulic pressure control mechanism, and further including a resistance that is electrically connected to the power supply through the power supply line, the diagnosis method including performing, by a diagnosis unit of the control device, a power supply line diagnosis in which an abnormality of the power supply line is diagnosed, in a state where no current is applied to the inlet valve but a current is applied to the resistance, based on a voltage change in the power supply line when the current to be applied to the resistance is changed. In a hydraulic pressure control unit, a brake system, and a diagnosis method according to the invention, the hydraulic pressure control unit includes: a hydraulic pressure control mechanism including an inlet valve as an electromagnetic valve that is electrically connected to a power supply through a power supply line, is provided to a flow path that communicates with a master cylinder and a wheel cylinder, and becomes an ope