Lubricating system for engagement mechanism

Patent metadata

Field	Value
Publication number	US-10487936-B2
Application number	US-201715452064-A
Country	US
Kind code	B2
Filing date	Mar 7, 2017
Priority date	Mar 9, 2016
Publication date	Nov 26, 2019
Grant date	Nov 26, 2019

Abstract

A first valve is disposed in an oil passage through which the engaging pressure generated by a linear solenoid valve is supplied to A second brake. The first valve is closed when the second brake is released, so as to close the oil passage, and is opened when the second brake is engaged, so as to open the oil passage. A second valve is disposed in a lubricating oil passage through which lubricating oil is supplied to the second brake, and communicates with the linear solenoid valve. The second valve is opened when the engaging pressure is supplied from the linear solenoid valve, so as to open the lubricating oil passage, and is closed when no engaging pressure is generated by the linear solenoid valve.

First claim

What is claimed is:

1. A lubricating system for supplying a lubricating oil to a frictional engagement mechanism,
the frictional engagement mechanism including
engaging elements configured to transmit torque by use of frictional force, and

a hydraulic part configured to press the engaging elements and generate the frictional force,
the lubricating system comprising:
an engaging pressure generator configured to generate an engaging pressure supplied to the hydraulic part;
a first valve configured to interrupt supply of the engaging pressure to the hydraulic part when the frictional engagement mechanism is placed in a released state; and
a second valve configured to operate in response to the engaging pressure, and supply the lubricating oil to the engaging elements when the frictional engagement mechanism is placed in the released state.

2. The lubricating system according to claim 1 , wherein:
the first valve is configured such that interruption of supply of the engaging pressure to the hydraulic part is cancelled when the frictional engagement mechanism is placed in an engaged state; and
the second valve is configured such that the lubricating oil is supplied to the engaging elements when the frictional engagement mechanism is placed in the engaged state.

3. The lubricating system according to claim 1 , further comprising
a lubricating oil passage through which the lubricating oil is supplied to the engaging elements, wherein
the second valve is configured to open the lubricating oil passage when the engaging pressure generated by the engaging pressure generator is supplied to the second valve.

4. The lubricating system according to claim 1 , further comprising
an electronic control unit configured to control opening and closing operation of the second valve, wherein
the electronic control unit is configured to operate the second valve such that the lubricating oil is supplied to the engaging elements, during a predetermined time after the frictional engagement mechanism is switched from an engaged state to the released state.

5. The lubricating system according to claim 4 , wherein
the predetermined time is a length of time required to make a quantity of heat generation equal to or smaller than a predetermined value, the quantity of heat generation being estimated based on the engaging pressure supplied to the hydraulic part of the frictional engagement mechanism and a rotational speed of the engaging elements.

6. The lubricating system according to claim 1 , further comprising
an oil passage through which the engaging pressure is supplied from the engaging pressure generator to the hydraulic part, wherein
the first valve is configured to:
shut off the oil passage by operating according to a given signal pressure generated when the frictional engagement mechanism is placed in the released state; and
open the oil passage when the given signal pressure is not generated.

Assignees

• Toyota Motor Co Ltd

Inventors

• Kishimoto Naoyuki
• Tabuchi Motoki
• Yoshino Hirotsugu

Classifications

• F16D2300/06

  Lubrication details not provided for in group F16D13/74 · CPC title

• F16H2200/0086

  the gear ratios comprising two reverse speeds · CPC title

• F16H57/0473 Primary

  Friction devices, e.g. clutches or brakes · CPC title

• F16H57/0435

  Pressure control for supplying lubricant; Circuits or valves therefor · CPC title

• F16D2048/029

  Hydraulic circuits combining clutch actuation with clutch lubrication or cooling · CPC title