793D Off-Highway Truck Power Train: Transmission Planetary

Components of the transmission (1) Input shaft (2) Rotating housing (3) Sun gear (4) Planetary gears (5) No. 1 clutch (6) No. 2 clutch (7) Center shaft (8) Rotating housing of No. 3 clutch (9) No. 3 clutch (10) Sun gear (11) Ring gear (12) No. 4 clutch (13) Ring gear (14) No. 5 clutch (15) Sun gear (16) No. 6 clutch (17) Hub (18) Sun gear (19) Planetary carrier (20) Planetary carrier and output shaft (21) Planetary gears (22) Ring gear (23) Planetary gears (24) Planetary gears (25) Planetary carrier (26) Coupling hub (27) Coupling ring gear (28) Ring gear(29) Planetary carrier

Table 1

Engagement of Transmission Clutches
Transmission Speed	Engaged Clutches in the Transmission
NEUTRAL-1	3
NEUTRAL-2	1
REVERSE	1 and 6
FIRST speed	1 and 5
SECOND speed	2 and 5
THIRD speed	1 and 4
FOURTH speed	2 and 4
FIFTH speed	1 and 3
SIXTH speed	2 and 3

Power from the engine goes to the torque converter. The power then goes through the drive shaft to the transfer gears. The transfer gears are fastened directly to the front of the transmission case. The power then goes through the planetary transmission to the differential.

The transmission has six forward speeds and one reverse speed. REVERSE and NEUTRAL use only torque converter drive. At lower ground speeds, FIRST speed uses torque converter drive. At higher ground speeds, FIRST speed uses direct drive. As the ground speed increases in FIRST speed, the lockup clutch of the torque converter engages. This provides FIRST speed with direct drive. The torque converter is always in direct drive for speeds SECOND through SIXTH, but there is a short period of torque converter drive when the clutches engage in the transmission. This provides smooth, automatic upshifting from SECOND through SIXTH and smooth, automatic downshifting from SIXTH through SECOND.

The transmission has a combination of three rotating clutches, three stationary clutches, and four planetary units. This provides six forward speeds and one reverse speed. No. 1 clutch (5), No. 2 clutch (6), and No. 3 clutch (9) are the rotating clutches.

Input torque goes from the transfer gears to input shaft (1). Input shaft (1) drives the rotating housing and the transmission input clutch arrangement. Center shaft (7) connects the input section to the output section. Center shaft (7) also carries the sun gears that drive the output section of the transmission. Center shaft (7) and input shaft (1) turn the same direction.

Power Flow in NEUTRAL-1

Power flow in NEUTRAL-1 (1) Input shaft (2) Rotating housing (3) Sun gear (4) Planetary gears (5) No. 1 clutch (6) No. 2 clutch (7) Center shaft (8) Rotating housing of No. 3 clutch (9) No. 3 clutch (10) Sun gear (11) Ring gear (12) No. 4 clutch (13) Ring gear (14) No. 5 clutch (15) Sun gear (16) No. 6 clutch (17) Hub (18) Sun gear (19) Planetary carrier (20) Planetary carrier and output shaft (21) Planetary gears (22) Ring gear (23) Planetary gears (24) Planetary gears (25) Planetary carrier (26) Coupling hub (27) Coupling ring gear (28) Ring gear(29) Planetary carrier

Only No. 3 clutch (9) is engaged in NEUTRAL-1. No input clutches are engaged. Torque is transferred from the transfer gears to input shaft (1). Rotating housing (2) is splined to input shaft (1). Rotating housing (2) turns with input shaft (1). Rotating housing (2) spins the plates of No. 1 clutch (5). Because No. 1 clutch (5) is not engaged, ring gear (28) is not held. Rotating housing (2) spins the plates of No. 2 clutch (6). Because No. 2 clutch (6) is not engaged, coupling ring gear (27) is not held.

Ring gear (28) and coupling ring gear (27) are not held. Torque is not transferred to planetary carrier (29) and center shaft (7) is not driven.

No. 3 clutch (9) is engaged. The discs of the No. 3 clutch hold coupling hub (26). Sun gear (10) is splined to center shaft (7). Because no input torque has been transferred to center shaft (7), there is no output torque.

Power Flow in NEUTRAL-2

No. 1 clutch (5) is engaged in NEUTRAL-2. Torque is transferred from the transfer gears to input shaft (1). Rotating housing (2) is splined to input shaft (1). Rotating housing (2) turns with input shaft (1). Rotating housing (2) spins the plates of No. 1 clutch (5). Because No. 1 clutch (5) is engaged, the discs of the No. 1 clutch hold ring gear (28) .

Ring gear (28) turns with rotating housing (2) and input shaft (1). Sun gear (3) is splined to a stationary shaft. Sun gear (3) does not turn. Planetary gears (4) move around the outside of sun gear (3). This drives planetary carrier (29). Planetary carrier (29) turns in the same direction as input shaft (1), but at a different speed. Planetary carrier (29) is splined to center shaft (7). Center shaft (7) and planetary carrier (29) are driven in the same direction and at the same speed.

No output clutches are engaged. The torque is lost through spinning clutch discs and plates. Torque does not flow to the output shaft.

Power Flow in FIRST Speed

No. 1 clutch (5) and No. 5 clutch (14) are engaged in FIRST speed. Torque is transferred from the transfer gears to input shaft (1). Rotating housing (2) is splined to input shaft (1). Rotating housing (2) turns with input shaft (1). Rotating housing (2) spins the plates of No. 1 clutch (5). Because No. 1 clutch (5) is engaged, the discs of the No. 1 clutch hold ring gear (28) .

Ring gear (28) turns with rotating housing (2) and input shaft (1). Sun gear (3) is splined to a stationary shaft. Sun gear (3) does not turn. Planetary gears (4) move around the outside of sun gear (3). This drives planetary carrier (29). Planetary carrier (29) turns in the same direction as input shaft (1), but at a different speed. Planetary carrier (29) is splined to center shaft (7). Center shaft (7) and planetary carrier (29) are driven in the same direction and at the same speed.

Sun gear (15) is splined to center shaft (7). Sun gear (15) turns planetary gears (23). No. 5 clutch (14) is engaged. The discs of No. 5 clutch (14) hold ring gear (13) stationary. Planetary gears (23) move around the inside of ring gear (13). This drives the planetary carrier and output shaft (20) .

The output shaft turns in the same direction as input shaft (1), but at a different speed.

Power Flow in FOURTH Speed

Power flow in FOURTH speed (1) Input shaft (2) Rotating housing (3) Sun gear (4) Planetary gears (5) No. 1 clutch (6) No. 2 clutch (7) Center shaft (8) Rotating housing of No. 3 clutch (9) No. 3 clutch (10) Sun gear (11) Ring gear (12) No. 4 clutch (13) Ring gear (14) No. 5 clutch (15) Sun gear (16) No. 6 clutch (17) Hub (18) Sun gear (19) Planetary carrier (20) Planetary carrier and output shaft (21) Planetary gears (22) Ring gear (23) Planetary gears (24) Planetary gears (25) Planetary carrier (26) Coupling hub (27) Coupling ring gear (28) Ring gear(29) Planetary carrier

No. 2 clutch (6) and No. 4 clutch (12) are engaged in FOURTH speed. Torque is transferred from the transfer gears to input shaft (1). Rotating housing (2) is splined to input shaft (1). Rotating housing (2) turns with input shaft (1). Rotating housing (2) spins the plates of No. 2 clutch (6). Because No. 2 clutch (6) is engaged, the discs of the No. 2 clutch hold coupling ring gear (27) .

Coupling ring gear (27) turns with rotating housing (2) and input shaft (1). Coupling ring gear (27) is splined to planetary carrier (29). Planetary carrier (29) turns with coupling ring gear (27). The planetary carrier is splined to center shaft (7). Center shaft (7) and input shaft (1) are driven in the same direction and at the same speed.

Sun gear (10) is splined to center shaft (7). Sun gear (10) turns planetary gears (24). No. 4 clutch (12) is engaged. The discs of No. 4 clutch (12) hold ring gear (11) stationary. Planetary gears (24) move around the inside of ring gear (11). This drives planetary carrier (25) in the same direction as center shaft (7), but at a different speed.

Planetary carrier (25) is splined to ring gear (13). Because No. 5 clutch (14) is not engaged, ring gear (13) turns with planetary carrier (25). Sun gear (15) is splined to center shaft (7). Sun gear (15) turns with center shaft (7). Sun gear (15) and ring gear (13) turn in the same direction but at different speeds. Planetary gears (23) move around the inside of ring gear (13). This drives the planetary carrier and output shaft (20) .

The output shaft turns in the same direction as input shaft (1), but at a different speed.

Power Flow in FIFTH Speed

No. 1 clutch (5) and No. 3 clutch (9) are engaged in FIFTH speed. Torque is transferred from the transfer gears to input shaft (1). Rotating housing (2) is splined to input shaft (1). Rotating housing (2) turns with input shaft (1). Rotating housing (2) spins the plates of No. 1 clutch (5). Because No. 1 clutch (5) is engaged, the discs of the No. 1 clutch hold ring gear (28) .

Ring gear (28) turns with rotating housing (2) and input shaft (1). Sun gear (3) is splined to a stationary shaft. Sun gear (3) does not turn. Planetary gears (4) move around the outside of sun gear (3). This drives planetary carrier (29). Planetary carrier (29) turns in the same direction as input shaft (1), but at a different speed. Planetary carrier (29) is splined to center shaft (7). Center shaft (7) and planetary carrier (29) are driven in the same direction and at the same speed.

Sun gear (10) is splined to center shaft (7). Sun gear (10) is also splined to coupling hub (26). No. 3 clutch (9) is engaged. The discs of No. 3 clutch (9) hold coupling hub (26). No. 3 clutch (9) is a rotating clutch. Rotating housing (8) of the No. 3 clutch and center shaft (7) turn in the same direction and at the same speed. Rotating housing (8) of the No. 3 clutch is fastened to planetary carrier (25). Planetary carrier (25) is splined to ring gear (13). Ring gear (13) and center shaft (7) turn in the same direction and at the same speed.

Sun gear (15) is splined to center shaft (7). Sun gear (15) and ring gear (13) turn in the same direction and at the same speed. This holds planetary gears (23). The planetary carrier and output shaft (20) are driven in the same direction as center shaft (7) and at the same speed as center shaft (7) .

Power Flow in SIXTH Speed

No. 2 clutch (6) and No. 3 clutch (9) are engaged in SIXTH speed. Torque is transferred from the transfer gears to input shaft (1). Rotating housing (2) is splined to input shaft (1). Rotating housing (2) turns with input shaft (1). Rotating housing (2) spins the plates of No. 2 clutch (6). Because No. 2 clutch (6) is engaged, the discs of the No. 2 clutch hold coupling ring gear (27) .

Coupling ring gear (27) turns with rotating housing (2) and input shaft (1). Coupling ring gear (27) is splined to planetary carrier (29). Planetary carrier (29) turns with coupling ring gear (27). The planetary carrier is splined to center shaft (7). Center shaft (7) and input shaft (1) are driven in the same direction and at the same speed.

Sun gear (10) is splined to center shaft (7). Sun gear (10) is also splined to coupling hub (26). No. 3 clutch (9) is engaged. The discs of No. 3 clutch (9) hold coupling hub (26). No. 3 clutch (9) is a rotating clutch. Rotating housing (8) of the No. 3 clutch and center shaft (7) turn in the same direction and at the same speed. Rotating housing (8) of the No. 3 clutch is fastened to planetary carrier (25). Planetary carrier (25) is splined to ring gear (13). Ring gear (13) and center shaft (7) turn in the same direction and at the same speed.

Sun gear (15) is splined to center shaft (7). Sun gear (15) and ring gear (13) turn in the same direction and at the same speed. This holds planetary gears (23). The planetary carrier and output shaft (20) are driven in the same direction as center shaft (7) and at the same speed as center shaft (7) .

The output shaft turns in the same direction as input shaft (1) and at the same speed.

Power Flow in REVERSE

No. 1 clutch (5) and No. 6 clutch (16) are engaged in REVERSE speed. Torque is transferred from the transfer gears to input shaft (1). Rotating housing (2) is splined to input shaft (1). Rotating housing (2) turns with input shaft (1). Rotating housing (2) spins the plates of No. 1 clutch (5). Because No. 1 clutch (5) is engaged, the discs of the No. 1 clutch hold ring gear (28) .

Ring gear (28) turns with rotating housing (2) and input shaft (1). Sun gear (3) is splined to a stationary shaft. Sun gear (3) does not turn. Planetary gears (4) move around the outside of sun gear (3). This drives planetary carrier (29). Planetary carrier (29) turns in the same direction as input shaft (1), but at a different speed. Planetary carrier (29) is splined to center shaft (7). Center shaft (7) and planetary carrier (29) are driven in the same direction and at the same speed.

Sun gear (15) is splined to center shaft (7). Sun gear (15) spins planetary gears (23). No. 5 clutch (14) is not engaged. Planetary gears (23) spin ring gear (13). Ring gear (13) turns in the opposite direction of sun gear (15). Hub (17) is splined to ring gear (13) and to sun gear (18). Sun gear (18) turns in the same direction as ring gear (13). Sun gear (18) turns planetary gears (21). No. 6 clutch (16) is engaged. The discs of No. 6 clutch (16) hold ring gear (22). Planetary gears (21) move around the inside of ring gear (22). This drives planetary carrier (19). Planetary carrier (19) is splined to the planetary carrier and output shaft (20). The planetary carrier (19) is driven at the same speed and direction as the planetary carrier and output shaft (20) .

The output shaft is driven in the opposite direction of center shaft (7) and input shaft (1) and at a different speed.

Lubrication of the Transmission

Lubrication of the transmission (1) Balance piston of No. 1 clutch (2) Planetary gears (3) No. 1 clutch (4) No. 2 clutch (5) Center shaft (6) Passage (7) No. 3 clutch (8) Sun gear (9) Ring gear (10) No. 4 clutch (11) Ring gear (12) No. 5 clutch (13) No. 6 clutch (14) Slinger (15) Planetary carrier (16) Planetary carrier and output shaft (17) Planetary gears (18) Ring gear (19) Planetary gears (20) Planetary gears (21) Planetary carrier (22) Passage (23) Coupling hub (24) Balance piston of No. 3 clutch (25) Balance piston of No. 2 clutch (26) Coupling ring gear (27) Ring gear (28) Planetary carrier (29) Passage(30) Passage

Oil for the lubrication of the transmission comes from the torque converter sump. The transmission lubrication section of the oil pump pulls oil through the suction screen. If the lockup clutch solenoid is activated, the oil combines with the signal oil that is flowing from the lockup clutch and synchronizing valve. The combined oil flows to the transfer case and the oil divides. Some of the oil remains in the transfer case and some of the oil flows to the transmission. Pressure is controlled by a relief valve in the transmission case.

Oil that remains in the transfer case lubricates the transfer gears and the bearings. Some of this oil flows through passage (30) to the back of balance piston (1) for the No. 1 clutch. This oil then goes through passage (29) and through passages in ring gear (27). This oil lubricates No. 1 clutch (3) .

The oil that flows to the transmission flows through passage (6) to center shaft (5). Some of the oil flows forward and some of the oil flows toward the output end. Part of the oil that flows forward goes to the back of balance piston (25) for the No. 2 clutch. Some of this oil lubricates ring gear (26) and No. 2 clutch (4). Some of the oil that flows forward from passage (6) flows through passages to planetary carrier (28) for the lubrication of planetary gears (2). The remainder of the oil that flows forward from passage (6) flows around center shaft (5) and into the center of center shaft (5) .

Part of the oil that flows toward the output end from passage (6) goes behind balance piston (24) for the No. 3 clutch. Some of this oil lubricates coupling hub (23) and No. 3 clutch (7). The remainder of the oil that flows toward the output end from passage (6) lubricates sun gear (8). Some of the oil flows from sun gear (8) through planetary carrier (21) for the lubrication of planetary gears (20). Some of the oil flows from sun gear (8) for the lubrication of ring gear (11) and No. 5 clutch (12). Some of the oil flows from the sun gear (8) through the planetary carrier and output shaft (16) for the lubrication of planetary gears (19). The remainder of the oil lubricates ring gear (9) and No. 4 clutch (10) .

The remainder of the oil that enters the transmission through passage (6) flows into passage (22). This oil helps lubricate No. 4 clutch (10), No. 5 clutch (12), and No. 6 clutch (13). This oil then flows into slinger (14). The oil is directed to passages that are in planetary carrier (15). This oil lubricates planetary gears (17), ring gear (18), and No. 6 clutch (13) .

Operation of the Balance Pistons in the Rotating Clutches

The oil that flows to balance piston (1) of the No. 1 clutch, to balance piston (25) of the No. 2 clutch, and to balance piston (24) of the No. 3 clutch is used to balance the centrifugal force of the oil. The centrifugal force of the oil is caused by the rotation of the No. 1 clutch, the No. 2 clutch, and the No. 3 clutch. The centrifugal force of the oil that is behind the clutch piston in the rotating clutches causes a small amount of clutch engagement in the rotating clutch. The centrifugal force of the oil that is behind the balance piston balances the centrifugal force of the oil that is on the clutch piston.

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793D Off-Highway Truck Power Train: Transmission Planetary 2013-01-06T19:56:00-08:00 Rating: 4.5 Diposkan Oleh: Unknown