Diagnostic device for hydraulic pressure control actuator

Patent metadata

Field	Value
Publication number	US-11988231-B2
Application number	US-201414221200-A
Country	US
Kind code	B2
Filing date	Mar 20, 2014
Priority date	Mar 27, 2013
Publication date	May 21, 2024
Grant date	May 21, 2024

Abstract

A diagnostic device diagnoses a hydraulic pressure control actuator which drives a line pressure control valve to regulate a pressure of hydraulic oil between upper and lower limit line pressures, so that the pressure approaches a predetermined target line pressure. The diagnostic device includes: an actual hydraulic pressure detection unit to detect an actual hydraulic pressure; a determination value setting unit to set a high pressure fixation determination value which is increased as the driving revolution rate is increased so as to substantially match a characteristic of the actuator at a time of high pressure fixation; and a fixation determination unit to determine high pressure fixation of the actuator when the actual hydraulic pressure substantially matches the high pressure fixation determination value with a difference between the target line pressure and the upper limit line pressure not lower than a predetermined value.

First claim

The invention claimed is:

1. A diagnostic device for a hydraulic pressure control actuator which drives a line pressure control valve to regulate a pressure of hydraulic oil between an upper limit line pressure and a lower limit line pressure, so that the pressure approaches a predetermined target line pressure, the hydraulic oil being discharged by a hydraulic pump which discharges hydraulic oil in an amount according to a driving revolution rate, the diagnostic device comprising:
an actual hydraulic pressure detection unit configured to detect an actual hydraulic pressure after the pressure is regulated by the line pressure control valve;
a determination value setting unit configured to set a high pressure fixation determination value which is increased as the driving revolution rate is increased so as to substantially match a characteristic of the hydraulic pressure control actuator at a time of high pressure fixation; and
a fixation determination unit configured to determine high pressure fixation of the hydraulic pressure control actuator when the actual hydraulic pressure substantially matches the high pressure fixation determination value with a difference between the target line pressure and the upper limit line pressure higher than or equal to a predetermined value.

2. The diagnostic device for a hydraulic pressure control actuator according to claim 1 ,
wherein the determination value setting unit sets a low pressure fixation determination value which is increased as the driving revolution rate is increased so as to substantially match a characteristic of the hydraulic pressure control actuator at a time of low pressure fixation, and
the fixation determination unit is configured to determine low pressure fixation of the hydraulic pressure control actuator when the actual hydraulic pressure substantially matches the low pressure fixation determination value with a difference between the target line pressure and the lower limit line pressure higher than or equal to a predetermined value.

3. The diagnostic device for a hydraulic pressure control actuator according to claim 2 ,
wherein the determination value setting unit corrects a determination value such that the determination value is increased as a hydraulic temperature decreases.

4. The diagnostic device for a hydraulic pressure control actuator according to claim 3 ,
wherein the determination value setting unit is configured to determine fixation only when an amount of control performed by the hydraulic pressure control actuator, the amount of control being set based on the target line pressure, and an amount of control actually commanded to the hydraulic pressure control actuator are both within a predetermined range.

5. The diagnostic device for a hydraulic pressure control actuator according to claim 2 ,
wherein the determination value setting unit is configured to determine fixation only when an amount of control performed by the hydraulic pressure control actuator, the amount of control being set based on the target line pressure, and an amount of control actually commanded to the hydraulic pressure control actuator are both within a predetermined range.

6. The diagnostic device for a hydraulic pressure control actuator according to claim 1 ,
wherein the determination value setting unit corrects a determination value such that the determination value is increased as a hydraulic temperature decreases.

7. The diagnostic device for a hydraulic pressure control actuator according to claim 6 ,
wherein the determination value setting unit is configured to determine fixation only when an amount of control performed by the hydraulic pressure control actuator, the amount of control being set based on the target line pressure, and an amount of control actually commanded to the hydraulic pressure control actuator are both within a predetermined range.

8. The diagnostic device for a hydraulic pressure control actuator according to claim 1 ,
wherein the determination value setting unit is configured to determine fixation only when an amount of control performed by the hydraulic pressure control actuator, the amount of control being set based on the target line pressure, and an amount of control actually commanded to the hydraulic pressure control actuator are both within a predetermined range.

9. A diagnostic device for a hydraulic pressure control actuator which drives a line pressure control valve to regulate a pressure of hydraulic oil between an upper limit line pressure and a lower limit line pressure, so that the pressure approaches a predetermined target line pressure, the hydraulic oil being discharged by a hydraulic pump which discharges hydraulic oil in an amount according to a driving revolution rate, the diagnostic device comprising:
an actual hydraulic pressure detection unit configured to detect an actual hydraulic pressure after the pressure is regulated by the line pressure control valve;
a determination value setting unit configured to set a low pressure fixation determination value which is increased as the driving revolution rate is increased so as to substantially match a characteristic of the hydraulic pressure control actuator at a time of low pressure fixation; and
a fixation determination unit configured to determine low pressure fixation of the hydraulic pressure control actuator when the actual hydraulic pressure substantially matches the low pressure fixation determination value with a difference between the target line pressure and the lower limit line pressure higher than or equal to a predetermined value.

10. The diagnostic device for a hydraulic pressure control actuator according to claim 9 ,
wherein the determination value setting unit corrects a determination value such that the determination value is increased as a hydraulic temperature decreases.

11. The diagnostic device for a hydraulic pressure control actuator according to claim 10 ,
wherein the determination value setting unit is configured to determine fixation only when an amount of control performed by the hydraulic pressure control actuator, the amount of control being set based on the target line pressure, and an amount of control actually commanded to the hydraulic pressure control actuator are both within a predetermined range.

12. The diagnostic device for a hydraulic pressure control actuator according to claim 9 ,
wherein the determination value setting unit is configured to determine fixation only when an amount of control performed by the hydraulic pressure control actuator, the amount of control being set based on the target line pressure, and an amount of control actually commanded to the hydraulic pressure control actuator are both within a predetermined range.

Assignees

• Fuji Heavy Ind Ltd
• Subaru Corp

Inventors

• Kinoshita Takahiro

Classifications

• F15B19/005 Primary

  Fault detection or monitoring · CPC title

• F16H61/12 Primary

  Detecting malfunction or potential malfunction, e.g. fail safe (in control of hydrostatic gearing F16H61/4192) {; Circumventing or fixing failures} · CPC title

• F16H2061/0068

  Method or means for testing of transmission controls or parts thereof · CPC title

• F15B2211/50554

  the pressure control means controlling a pressure downstream of the pressure control means, e.g. pressure reducing valve · CPC title

• F15B2211/526

  electrically or electronically · CPC title