Mazda Automatic Transaxle JA5A-EL. Manual — part 6

AUTOMATIC TRANSAXLE

K–5

K

TORQUE CONVERTER DESCRIPTION

AME561419100A01

Outline

• The JA5A-EL uses a three-element, single-gear, two-phase torque converter with torque converter clutch

(TCC) mechanism.

• The torque converter efficiently matches the output characteristic of AJ engine.

• By matching the output characteristics of the engine in order to optimize the configuration of the impellers, the

torque converter increases the capacity coefficient in the practical range, thereby improving drivability and fuel

economy.

• The TCC mechanism under certain conditions transmits the drive force by automatically connecting the pump

impeller with the turbine runner as opposed to using fluid. Therefore it prevents the torque converter from

slipping.

End Of Sie

AMU0517A503

K–6

AUTOMATIC TRANSAXLE

POWERTRAIN DESCRIPTION

AME561401030A05

Component Descriptions

Note

• All rotations are viewed from the side cover.

Component

Function

Low clutch

• Transmits rotation of low clutch drum to rear internal gear

• Operate in 1GR, 2GR, and 3GR operation

2-4 brake

• Prevents rotation of front sun gear

• Operate in 2GR, 4GR, and 5GR operation

High clutch

• Transmits rotation of input shaft to front planetary carrier

• Operate in 3GR, 4GR, and 5GR operation

Reverse clutch

• Transmits rotation of input shaft to front sun gear

• Operates when vehicle is backing

Reduction brake

• Prevents rotation of direct clutch drum and prevents rotation of reduction sun gear

Low and reverse brake

• Prevents rotation of low clutch drum and front planetary carrier

Direct clutch

• Transmits rotation of reduction planetary carrier to reduction sun gear

• Operates in 5GR position

Low one-way clutch

• Locks clockwise rotation of front planetary carrier

Reduction one-way clutch

• Locks counterclockwise rotation of reduction sun gear

AUTOMATIC TRANSAXLE

K–7

K

AMU0517A504

K–8

AUTOMATIC TRANSAXLE

Low Clutch, High Clutch, Reverse Clutch, 2-4 Brake, Low and Reverse Brake, Direct Clutch

Structure/Operation

• The basic structure is as shown in the figure below. In figure A, the fluid is in the clutch plates (drive plates,

driven plates) and the power is not transmitted because of the fluid slippage on each plate. Figure B shows the

clutch condition with the hydraulic pressure acting on the piston; the drive plates and the driven plates are

pressed tightly together to transmit the clutch drum rotation speed to the hub. When the hydraulic pressure in

the piston is drained, the clutches are separated because of the return spring and return to the condition in

figure A.

• The dished plates used for each clutch and brake reduce the shock caused by the sudden clutch engagement.

The piston check ball built in the reverse clutch drains the ATF only during freewheel to prevent the hydraulic

pressure from increasing to half-engage the clutches because of the residual ATF. In the low clutch and high

clutch, the centrifugal balance chamber is installed opposite the general clutch chamber.

One-Way Clutch

Low one-way clutch

Structure

• The low one-way clutch locks the clockwise rotation (seen from the side cover side) of the front planetary

carrier. The low one-way clutch operates in D range of the 1GR.

• The low one-way clutch inner race is integrated on contact with low clutch drum, and the low one-way clutch

outer race is fixed to the transaxle case.

Operation

• The low one-way clutch inner race (front

planetary carrier) rotates counterclockwise (seen

from the side cover side) freely, but the rollers

move to the shallower grooves and enter between

the races to the rotation when the inner race tries

to rotate clockwise.

• The low one-way clutch locks the clockwise

rotation of the front planetary carrier.

Note

• All direction of rotation are viewed from the

side cover.

AMU0517A505

AMU0517A507