GB2040015A - Toothed gearing - Google Patents

Abstract

In a planet carrier for a spur-gear type planetary gearset, the planet pins 23 are located against axial movement and against rotation by spring rings 31, 35 received in grooves 32, 36 in the planet carrier. <IMAGE>

Description

SPECIFICATION Planetary gear sets This invention relates to spur-gear type planetary gearsets (hereinafter referred to as being of the type specified) comprising a sun gear, an annulus gear and a planet carrier supporting planet gears located between the sun and annulus gears and rotatable on planet pins.

The invention is concerned in detail with the location of the planet pins in the planet carrier. These pins require to be held against rotation and to be located axially.

According to the invention, in a planet carrier for a planetary gearset of the type specified, the planet pins are located against rotation and movement axially in at least one direction by a spring ring received in a groove in the planet carrier.

Preferably the ring engages shoulders on the planet pins to prevent rotation thereof. These shoul ders may be formed between surfaces on end portions of the pins, which surfaces engage the ring to prevent rotation of the pins, and the main bodies of the pins.

The pins may be located in a direction opposite to said one direction by a further spring ring engaged in a further groove in the planet carrier.

The invention will now be described in detail by way of example with reference to the accompanying drawings in which: Figure 1 is a longitudinal section through the end portion of a drive axle for a motor vehicle including a planetary gearset; and Figures 2 and 3 are views in directions parallel to the axis of the axle showing the locating rings for the planet pins.

Referring now to the drawing, the end of an axle casing is indicated at 10 and rotatable on the end of the casing is a hub 11; the hub is mounted on bearings 12. An oil seal 13 is located between the hub and the casing. Within the hub is located brake mechanism indicated generally at 14.

The hub is driven from a drive shaft 15 through a spur-gear type planetary gearset. The sun gear of this gearset is indicated at 16 and is formed directly on the end of the drive shaft. The planet carrier is indicated at 17 and is a generally cylindrical member fitting within the hub and having a flange 18 which is bolted at 19 to the outer end of the hub.

Received in pockets in the wall of the planet carrier is a plurality of planet gears, one of which is shown at 21. Each gear is mounted on needle roller bearings 22 on a planet pin 23. Thrust washers 24 are located between the ends of the planet gear and the pocket in which it is received.

The planet gears mesh with an annulus gear 25 formed in a sleeve 26. The right hand end of the sleeve is splined to a plate 27 and is located axially relative thereto by a number of plates 29 fitting into an annular groove 28 in the gear 25, the plates 29 being pinned to the plate 27. The plate 27 is bolted direct to the end of the axle casing by bolts 30. Thus far the arrangement is of conventional construction.

The planet pins 23 are located axially in the planet carrier and are prevented from rotating therein by two spring rings. Thus there is an internal ring 31 at the right hand end of the planet carrier which is received in an internal groove 32 in the planet carrier and is shown in more detail in Figure 3. The right hand end of each planet pin 23 is formed with a flat 33 as shown clearly in Figure 3 and these flats engage the internal periphery of the ring thus preventing the pins from rotating. Moreover, there are shoulders 34 formed between the flats and the main bodies of the pins and these are engaged by the ring 31 and locate the pins against movement to the right in Figure 1. The flats 33 may be replaced by arcuate surfaces which engage the inner surface of the ring 37.

At the left hand end of the planet carrier in Figure 1, there is a further spring ring 35 shown in detail in Figure 2 which is received in an external groove 36 in the planet carrier and overlaps the left hand ends of the planet pins thus preventing axial movement to the left in Figure 1. It will be seen that the rings 31 and 35 locate the planet pins against axial movement and also locate them against rotation.

The ring 31 has been shown fitting into an internal groove in the planet carrier however it could fit into an external groove in the same way as the ring 35 fits into the ring 36. In addition, or alternatively, the ring such as 35 could fit into an internal groove in a manner similar to the ring 31. The means to prevent rotation of the planet pin could be at the left hand end of the hub instead of at the right hand end as shown. The ring which prevents axial movement only, i.e. the ring 35 in the example shown, could be replaced by some other means for locating the planet pins, e.g. a cover plate.

1. A planet carrier for a planetary gearset of the type specified wherein the planet pins are located against rotation and movement axially in at least one direction by a spring ring received in a groove in the planet carrier.

2. A planet carrier according to Claim 1 wherein the ring engages shoulders on the planet pins to prevent rotation thereof.

3. A planet carrier according to Claim 2 wherein the shoulders are formed between surfaces on the end portions of the pins which engage said ring to prevent rotation of the pins and the main bodies of the pins.

4. A planet carrier according to any one of the preceding claims wherein the pins are located against movement axially in a direction opposite to said one direction by a further spring ring engaged in a further groove in the planet carrier.

5. A spur-gear type planetary gearset including a planet carrier as claimed in any one of the preceding claims.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Planetary gear sets This invention relates to spur-gear type planetary gearsets (hereinafter referred to as being of the type specified) comprising a sun gear, an annulus gear and a planet carrier supporting planet gears located between the sun and annulus gears and rotatable on planet pins. The invention is concerned in detail with the location of the planet pins in the planet carrier. These pins require to be held against rotation and to be located axially. According to the invention, in a planet carrier for a planetary gearset of the type specified, the planet pins are located against rotation and movement axially in at least one direction by a spring ring received in a groove in the planet carrier. Preferably the ring engages shoulders on the planet pins to prevent rotation thereof. These shoul ders may be formed between surfaces on end portions of the pins, which surfaces engage the ring to prevent rotation of the pins, and the main bodies of the pins. The pins may be located in a direction opposite to said one direction by a further spring ring engaged in a further groove in the planet carrier. The invention will now be described in detail by way of example with reference to the accompanying drawings in which: Figure 1 is a longitudinal section through the end portion of a drive axle for a motor vehicle including a planetary gearset; and Figures 2 and 3 are views in directions parallel to the axis of the axle showing the locating rings for the planet pins. Referring now to the drawing, the end of an axle casing is indicated at 10 and rotatable on the end of the casing is a hub 11; the hub is mounted on bearings 12. An oil seal 13 is located between the hub and the casing. Within the hub is located brake mechanism indicated generally at 14. The hub is driven from a drive shaft 15 through a spur-gear type planetary gearset. The sun gear of this gearset is indicated at 16 and is formed directly on the end of the drive shaft. The planet carrier is indicated at 17 and is a generally cylindrical member fitting within the hub and having a flange 18 which is bolted at 19 to the outer end of the hub. Received in pockets in the wall of the planet carrier is a plurality of planet gears, one of which is shown at 21. Each gear is mounted on needle roller bearings 22 on a planet pin 23. Thrust washers 24 are located between the ends of the planet gear and the pocket in which it is received. The planet gears mesh with an annulus gear 25 formed in a sleeve 26. The right hand end of the sleeve is splined to a plate 27 and is located axially relative thereto by a number of plates 29 fitting into an annular groove 28 in the gear 25, the plates 29 being pinned to the plate 27. The plate 27 is bolted direct to the end of the axle casing by bolts 30. Thus far the arrangement is of conventional construction. The planet pins 23 are located axially in the planet carrier and are prevented from rotating therein by two spring rings. Thus there is an internal ring 31 at the right hand end of the planet carrier which is received in an internal groove 32 in the planet carrier and is shown in more detail in Figure 3. The right hand end of each planet pin 23 is formed with a flat 33 as shown clearly in Figure 3 and these flats engage the internal periphery of the ring thus preventing the pins from rotating. Moreover, there are shoulders 34 formed between the flats and the main bodies of the pins and these are engaged by the ring 31 and locate the pins against movement to the right in Figure 1. The flats 33 may be replaced by arcuate surfaces which engage the inner surface of the ring 37. At the left hand end of the planet carrier in Figure 1, there is a further spring ring 35 shown in detail in Figure 2 which is received in an external groove 36 in the planet carrier and overlaps the left hand ends of the planet pins thus preventing axial movement to the left in Figure 1. It will be seen that the rings 31 and 35 locate the planet pins against axial movement and also locate them against rotation. The ring 31 has been shown fitting into an internal groove in the planet carrier however it could fit into an external groove in the same way as the ring 35 fits into the ring 36. In addition, or alternatively, the ring such as 35 could fit into an internal groove in a manner similar to the ring 31. The means to prevent rotation of the planet pin could be at the left hand end of the hub instead of at the right hand end as shown. The ring which prevents axial movement only, i.e. the ring 35 in the example shown, could be replaced by some other means for locating the planet pins, e.g. a cover plate. CLAIMS

1. A planet carrier for a planetary gearset of the type specified wherein the planet pins are located against rotation and movement axially in at least one direction by a spring ring received in a groove in the planet carrier.

2. A planet carrier according to Claim 1 wherein the ring engages shoulders on the planet pins to prevent rotation thereof.

3. A planet carrier according to Claim 2 wherein the shoulders are formed between surfaces on the end portions of the pins which engage said ring to prevent rotation of the pins and the main bodies of the pins.

4. A planet carrier according to any one of the preceding claims wherein the pins are located against movement axially in a direction opposite to said one direction by a further spring ring engaged in a further groove in the planet carrier.

5. A spur-gear type planetary gearset including a planet carrier as claimed in any one of the preceding claims.