Automatic transmission

• US 9,869,384 B2
• Filed: 08/30/2016
• Issued: 01/16/2018
• Est. Priority Date: 09/04/2015
• Status: Active Grant

• Current Assignee: Mazda Motor Corporation
• Original Assignee: Mazda Motor Corporation
• Inventors: Sako, Kaori, Mizobe, Tatsutoshi, Kamada, Shinya
• Primary Examiner(s): Wright, Dirk
• Application Number:
  US15/251,776
• Publication Number:
  US 20170067553A1
• Time in Patent Office: 504 Days
• Field of Search: None
• CPC Class Codes: F16H 1/00 Toothed gearings for conveying rotary motion specific for conveying rotary motion with variable gear ratio or for reversing rotary motion F16H3/00
• CPC Class Codes: F16H 2061/0037 characterised by controlled fluid supply to lubrication circuits of the gearing see also lubrication control F16H57/0446
• CPC Class Codes: F16H 2200/006 the gear ratios comprising eight forward speeds
• CPC Class Codes: F16H 2200/2012 with four sets of orbital gears
• CPC Class Codes: F16H 2200/2043 with five engaging means
• CPC Class Codes: F16H 3/66 composed of a number of gear trains without drive passing from one train to another
• CPC Class Codes: F16H 57/0409 characterised by the problem to increase efficiency, e.g. by reducing splash losses
• CPC Class Codes: F16H 57/0435 Pressure control for supplying lubricant; Circuits or valves therefor
• CPC Class Codes: F16H 57/045 Lubricant storage reservoirs, e.g. reservoirs in addition to a gear sump for collecting lubricant in the upper part of a gear case
• CPC Class Codes: F16H 57/0473 Friction devices, e.g. clutches or brakes
• CPC Class Codes: F16H 57/0482 Gearings with gears having orbital motion
• CPC Class Codes: F16H 57/0484 with variable gear ratio or for reversing rotary motion
• CPC Class Codes: F16H 57/10 Braking arrangements
• CPC Class Codes: F16H 61/0021 Generation or control of line pressure
• CPC Class Codes: F16H 61/30 Hydraulic or pneumatic motors or related fluid control means therefor

Abstract

An automatic transmission is provided with a brake device provided with a rotatable rotation-side friction plate and a non-rotatable fixed-side friction plate; a transmission case which accommodates the brake device; a lubrication oil supply section which supplies lubrication oil introduced into the transmission case to an upper portion of the brake device; and a lubrication oil discharge section disposed below the brake device, and configured to discharge lubrication oil supplied from the lubrication oil supply section to the brake device.

Claims

1. An automatic transmission comprising:

a brake device including a rotatable rotation-side friction plate interconnected with a predetermined rotation element, and a non-rotatable fixed-side friction plate disposed to face the rotation-side friction plate, the brake device being switchable between an engaged state where the friction plates are brought into pressing contact with each other, and a released state where the engaged state is released;

a transmission case which accommodates the brake device;

a lubrication oil supply section which supplies lubrication oil introduced into the transmission case to an upper portion of the brake device; and

a lubrication oil discharge section disposed below the brake device, and configured to discharge lubrication oil supplied from the lubrication oil supply section to the brake device.

2. The automatic transmission according to claim 1, further comprising:

a lubrication oil flow section formed independently of or integrally with the transmission case, the lubrication oil flow section serving as an oil passage for guiding, lubrication oil introduced into the transmission case to the lubrication oil supply section.

3. The automatic transmission according to claim 2, further comprising:

a planetary gear set including a sun gear, a plurality of pinions engaged with the sun gear, and a ring gear engaged with each of the pinions, wherein

the lubrication oil flow section is disposed at such a position that at least a part of the lubrication oil flow section overlaps the planetary gear set when viewed in a radial direction.

4. The automatic transmission according to claim 3, further comprising:

a clutch device including a rotatable input-side friction plate and a rotatable output-side friction plate disposed to face each other, the clutch device being switchable between an engaged state where the friction plates are brought into pressing contact with each other, and a released state where the engaged state is released, wherein

the lubrication oil flow section is disposed at such a position that at least a part of the lubrication oil flow section overlaps the clutch device when viewed in a radial direction.

5. The automatic transmission according to claim 4, further comprising:

an engagement hydraulic chamber to which a hydraulic pressure for use in engaging the brake device is supplied, wherein

the lubrication oil flow section is disposed on a side opposite to the engagement hydraulic chamber with respect to the brake device.

6. The automatic transmission according to claim 5, wherein

the lubrication oil discharge section includes a discharge control valve which is openably and closably provided to control discharge of lubrication oil from the brake device.

7. The automatic transmission according to claim 6, wherein

the lubrication oil supply section includes a supply control valve which is openably and closably provided to control supply of lubrication oil to the brake device.

8. The automatic transmission according to claim 7, wherein

the supply control valve is controlled by an engagement hydraulic pressure for use in engaging the brake device.

9. The automatic transmission according to claim 8, further comprising:

an input shaft to which a driving force is input from a power source mounted in a vehicle, wherein

the brake device is slip-controlled when the vehicle is started.

10. The automatic transmission according to claim 9, wherein

the input shaft is connected to the power source without via a power transmission device using fluid.

11. The automatic transmission according to claim 2, further comprising:

a clutch device including a rotatable input-side friction plate and a rotatable output-side friction plate disposed to face each other, the clutch device being switchable between an engaged state where the friction plates are brought into pressing contact with each other, and a released state where the engaged state is released, wherein

the lubrication oil flow section is disposed at such a position that at least a part of the lubrication oil flow section overlaps the clutch device when viewed in a radial direction.

12. The automatic transmission according to claim 2, further comprising:

an engagement hydraulic chamber to which a hydraulic pressure for use in engaging the brake device is supplied, wherein

the lubrication oil flow section is disposed on a side opposite to the engagement hydraulic chamber with respect to the brake device.

13. The automatic transmission according to claim 2, wherein

the lubrication oil discharge section includes a discharge control valve which is openably and closably provided to control discharge of lubrication oil from the brake device.

14. The automatic transmission according to claim 1, wherein

the lubrication oil discharge section includes a discharge control valve which is openably and closably provided to control discharge of lubrication oil from the brake device.

15. The automatic transmission according to claim 14, wherein

the lubrication oil supply section includes a supply control valve which is openably and closably provided to control supply of lubrication oil to the brake device.

16. The automatic transmission according to claim 1, wherein the lubrication oil supply section includes a supply control valve which is openably and closably provided to control supply of lubrication oil to the brake device.

17. The automatic transmission according to claim 16, wherein

the supply control valve is controlled by an engagement hydraulic pressure for use in engaging the brake device.

18. The automatic transmission according to claim 1, further comprising:

an input shaft to which a driving force is input from a power source mounted in a vehicle, wherein

the brake device is slip-controlled when the vehicle is started.

19. The automatic transmission according to claim 18, wherein

the input shaft is connected to the power source without via a power transmission device using fluid.

20. An automatic transmission comprising:

a brake device including a rotatable rotation-side friction plate interconnected with a predetermined rotation element, and a non-rotatable fixed-side friction plate disposed to face the rotation-side friction plate, the brake device being switchable between an engaged state where the friction plates are brought into pressing contact with each other, and a released state where the engaged state is released;

a transmission case which accommodates the brake device;

a lubrication oil flow section through which lubrication oil introduced into the transmission case is allowed to flow;

a lubrication oil supply section which supplies lubrication oil within the lubrication oil flow section to an upper portion of the brake device; and

an engagement hydraulic chamber to which a hydraulic pressure for use in engaging the brake device is supplied, wherein

the lubrication oil flow section is disposed on a side opposite to the engagement hydraulic chamber with respect to the brake device.