Planetary carrier assembly with stamped planetary spider configured for balancing holes

Abstract

A planetary carrier assembly is provided having a main planet carrier body and a stamped planetary spider formed from a planetary spider blank made of sheet or plate material. The planetary spider has a central portion that extends in a plane perpendicular to an axis of the main planet carrier body, and at least two flanges that extend integrally from the central portion in a direction parallel to the axis toward the main planet carrier body that form spider connection legs. The at least two flanges further include integrally connected distal balance portions that extend from ends of the spider connection legs and are folded back toward respective inner surfaces thereof. The ends of the spider connection legs are fastened to the main planet carrier body and the balance portions are configured for mass removal as part of a dynamic balancing of the planetary carrier assembly.

Claims

1. A planetary carrier assembly, comprising: a main planet carrier body; a stamped planetary spider formed from a planetary spider blank made of sheet or plate material having a generally uniform thickness that includes a central portion that extends in a plane perpendicular to an axis of the main planet carrier body, and at least two flanges that extend integrally from the central portion in a direction parallel to the axis toward the main planet carrier body that form spider connection legs, and the at least two flanges further include integrally connected distal balance portions that extend from ends of the spider connection legs and are folded back toward respective inner surfaces of the spider connection legs; wherein the ends of the spider connection legs are fastened to the main planet carrier body, and the balance portions are configured for mass removal as part of a dynamic balancing of the planetary carrier assembly; and at least one balancing hole in at least one of the balance portions.

2. The planetary carrier assembly of claim 1, wherein the central portion includes holes that are configured to receive planet pins.

3. The planetary carrier assembly of claim 1, wherein the ends of the spider connection legs include a matching interface to the main planet carrier body.

4. The planetary carrier assembly of claim 1, wherein the spider connection legs are welded to the main planet carrier body.

5. The planetary carrier assembly of claim 1, further comprising a planetary plate on an opposite axial side of the main planet carrier body from the stamped planetary spider.

6. The planetary carrier assembly of claim 5, wherein the central portion includes holes that are configured to receive planet pins, and the planetary plate includes corresponding holes configured to receive respective opposite ends of the planet pins.

7. A planetary carrier assembly, comprising: a main planet carrier body; a stamped planetary spider formed from a planetary spider blank made of sheet or plate material having a generally uniform thickness that includes a central portion that extends in a plane perpendicular to an axis of the main planet carrier body, and at least two flanges that extend integrally from the central portion in a direction parallel to the axis toward the main planet carrier body that form spider connection legs, and the at least two flanges further include integrally connected distal balance portions that extend from ends of the spider connection legs and are folded back toward respective inner surfaces of the spider connection legs; wherein the ends of the spider connection legs are fastened to the main planet carrier body, and the balance portions are configured for mass removal as part of a dynamic balancing of the planetary carrier assembly; and the integrally connected distal balance portions that extend from the ends of the spider connection legs are folded back onto the respective inner surfaces of the spider connection legs.

8. A method of assembling a planetary carrier assembly, the method comprising: stamping a planetary spider blank from sheet or plate material having a generally uniform thickness that includes a central portion that is adapted to extend in a plane perpendicular to an axis of a main planet carrier body, and at least two flanges that extend integrally from the central portion; bending the at least two flanges in a direction parallel to the axis to form spider connection legs; folding back integrally connected distal balance portions that extend from ends of the spider connection legs toward respective inner surfaces of the spider connection legs to form the planetary spider; providing a main planet carrier body; fastening the ends of the spider connection legs to the main planet carrier body to form the planetary carrier assembly, wherein the balance portions are configured for mass removal as part of a dynamic balancing of the planetary carrier assembly; and dynamically balancing the planetary carrier assembly by removing material from at least one of the balance portions located on an inside of the planetary spider.

9. The method of claim 8, further comprising: machining an interface on the ends of the spider connection legs prior to fastening to the main planet carrier body.

10. The method of claim 8, wherein the fastening of the ends of the spider connection legs to the main planet carrier body is carried out by welding.

11. The method of claim 8, further comprising: fastening a planetary plate on an opposite axial side of the main planet carrier body from the planetary spider.

12. The method of claim 8, wherein the stamping a planetary spider blank from sheet or plate material further includes stamping holes that are configured to receive planet pins.

13. The method of claim 8, wherein the planetary spider blank is made from sheet or plate steel.

14. The method of claim 8, wherein the integrally connected distal balance portions that extend from ends of the spider connection legs are folded back onto the respective inner surfaces of the spider connection legs.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The foregoing Summary and the following detailed description will be better understood when read in conjunction with the appended drawings, which illustrate a preferred embodiment of the invention. In the drawings:

(2) FIG. 1 is a perspective view of a prior art planetary carrier assembly as discussed in the Background Section.

(3) FIG. 2 is an enlarged portion of the prior art planetary carrier assembly shown in FIG. 1.

(4) FIG. 3 is an axial end view of the prior art planetary carrier assembly shown in FIG. 1.

(5) FIG. 4 is a cross-sectional view taken along line 4-4 of the prior art planetary carrier assembly shown in FIG. 3.

(6) FIG. 5 is a planetary spider blank for an embodiment of the present planetary carrier assembly.

(7) FIG. 6 is a perspective view of the planetary spider having flanges that extend integrally from the central portion in a direction parallel to the axis that form spider connection legs, as well as integrally connected distal balance portions that extend from ends of the spider connection legs that are folded back on respective inner surfaces of the spider connection legs.

(8) FIG. 7 is a axial end view of the stamped planetary spider shown in FIG. 6.

(9) FIG. 8 is a cross-sectional view taken along line 8-8 in FIG. 7 through the stamped planetary spider.

(10) FIG. 9 is a cross-sectional view similar to FIG. 8 in which ends of the spider connection legs have been machined to include a matching interface for the main planet carrier body.

(11) FIG. 10 is a perspective view of an embodiment of a planetary carrier assembly including the stamped planetary spider shown in FIGS. 5-9.

(12) FIG. 11 is an enlarged view of a portion of FIG. 10.

(13) FIG. 12 is an axial end view of the planetary carrier assembly shown in FIG. 10.

(14) FIG. 13 is a cross-section view taken along line 13-13 in FIG. 12.

DETAILED DESCRIPTION

(15) Certain terminology is used in the following description for convenience only and is not limiting. The words “inwardly” and “outwardly” refer to directions toward and away from the parts referenced in the drawings. “Axially” refers to a direction along the axis of a shaft. “Radially” refers to a direction normal to an axis. A reference to a list of items that are cited as, for example, “at least one of a or b” (where a and b represent the items being listed) means any single one of the items a or b, or a combination of a and b thereof. This would also apply to lists of three or more items in like manner so that individual ones of the items or combinations thereof are included. The terms “about” and “approximately” encompass + or −10% of an indicated value unless otherwise noted. The terminology includes the words specifically noted above, derivatives thereof and words of similar import.

(16) Referring to FIGS. 1-4, a prior art planetary carrier assembly 10 is shown in which the planetary spider 2 is formed as a forged part and balancing holes 3 are drilled into the radially outer flange 5 from radially outside.

(17) Referring to FIGS. 5-13, an embodiment of a planetary carrier assembly 10 according to the present disclosure is shown. FIGS. 5-9 show the stamped planetary spider 20 in detail starting with the planetary spider blank 22 shown in FIG. 5 to the finished planetary spider 20 shown in FIG. 9. The assembled planetary carrier assembly 10 is shown in FIGS. 10-13.

(18) The planetary carrier assembly 10 includes a main planet carrier body 14, shown in FIGS. 10-13. This can include external splines for a clutch pack, or another interface. The main planet carrier body is preferably formed from steel, and may be forged with post-machining.

(19) The stamped planetary spider 20, which is formed from the planetary spider blank 22 shown in FIG. 5, is formed by stamping in contrast to the prior art planetary spider 2 that was a forged part. Here, the planetary spider blank 22 is made of a sheet or plate material, preferably carbon steel, having a generally uniform thickness. The stamped planetary spider 20 includes a central portion 24 that extends in a plane perpendicular to an axis A of the main planet carrier body 14, and includes at least two flanges (in the illustrated embodiment there are four flanges 26A-26D) that extend integrally from the central portion 24 in a direction parallel to the axis A toward the main planet carrier body 14 that form the spider connection legs 28A-28D, shown in detail in FIGS. 6-9. The at least two flanges 26A-26D further include integrally connected distal balance portions 30A-30D that extend from the ends 29A-29D of the spider connection legs 28A-28D and are folded back toward, and in the illustrated embodiment onto, respective inner surfaces 32A-32D of the spider connection legs 28A-28D.

(20) As shown in FIGS. 10, 11, and 13, the ends 29A-29D of the spider connection legs 28A-28D are fastened to the main planet carrier body 14, preferably by welding, and the balance portions 30A-30D are configured for mass removal, such as by drilling balancing holes 38 in at least one of the balance portions 30A-30D, as part of a dynamic balancing of the planetary carrier assembly 10. The balancing holes 38 are shown in the balance portion 30D in FIG. 11. However, they could also be in one or more of the other balance portions 30A-30C, depending on the balancing requirements.

(21) As shown in FIG. 5, the central portion 24 may include holes 34 that are configured to receive planet pins, with these holes 34 being formed as part of the stamping process.

(22) Also, as shown in detail in FIG. 9, the ends 29A-29D of the spider connection legs 28A-28D preferably include a matching interface 36, formed by machining, to the main planet carrier body 14. The interface 36 can be a flattened slot or groove that is adapted to fit tightly against the corresponding part of the main planet carrier housing 14. This fit ensures better alignment and balance, as well as provides a recess for a weld bead during assembly.

(23) The stamped planetary spider 20 is assembled to the main planet carrier body 14 in a similar manner to the prior known planet carrier assembly 1, preferably by welding. A planetary plate 16 is connected on an opposite axial side of the main planet carrier body 14 from the stamped planetary spider 20. This is preferably also done by welding.

(24) The planetary plate 16 preferably includes corresponding holes 17 configured to received respective opposite ends of the planet pins such that the planet pins are supported by the holes 34 in the stamped planetary spider 20 and the corresponding holes 17 in the planetary plate 16. Other features, such as a splined connection can be attached to the planetary plate 16.

(25) A method of assembling a planetary carrier assembly 10 is also provided. The method includes the following steps:

(26) A) Stamping a planetary spider blank 22 from a sheet or plate material having a generally uniform thickness that includes a central portion 24 that is adapted to extend in a plane perpendicular to an axis A of a main planet carrier body 14, and at least two flanges 25A-26D that extend integrally from the central portion 24;

(27) B) Bending the at least two flanges 26A-26D in a direction parallel to the axis A to form spider connection legs 28A-28D;

(28) C) Folding back integrally connected distal balance portions 30A-30D that extend from the ends 29A-29D of the spider connection legs 28A-28D toward respective inner surfaces 32A-32D of the spider connection legs 28A-28D to form the planetary spider 20;

(29) D) Providing a main carrier body 14;

(30) E) Fastening the ends 29A-29D of the spider connection legs 28A-28D to the main planet carrier body 14, preferably by welding, to form the planetary carrier assembly 10, wherein the balance portions 30A-30D are configured for mass removal, preferably by drilling balancing holes 38 into the balance portions 30A-30D as part of the dynamic balancing process of the planetary carrier assembly 10.

(31) It is noted that the folding back integrally connected distal balance portions 30A-30D in step C) can be before or after the bending the at least two flanges 26A-26D in a direction parallel to the axis A to form the spider connection legs 28A-28D in step B). In the illustrated embodiment, the integrally connected distal balance portions 30A-30D are folded back onto the respective inner surfaces 32A-32D of the spider connection legs 28A-28D.

(32) As shown in detail in FIG. 11, the balancing holes 38 are drilled from inside the planetary spider 20, in contrast to the prior known planet carrier assembly where the balancing holes 3 were drilled from radially outside.

(33) The method may further include machining an interface 36 on the ends 29A-29D of the spider connection legs 28A-28D prior to fastening the planetary spider to the main planet carrier body 14.

(34) Additionally, in order to complete the planetary carrier assembly, additional components such as a planetary plate 16 can be attached, with the planetary plate 16 being fastened on an opposite axial side of the main planet carrier body 14 from the planetary spider 20.

(35) As part of the stamping process for the planetary spider blank 22, it is possible to include stamping the holes 34 that are configured to receive the planet pins as well as the access hole through the central portion 24 which allows the planet gears to be inserted during further assembly of the planetary carrier assembly and also reduces the overall weight of the planetary spider 20.

(36) Having thus described the presently preferred embodiments in detail, it is to be appreciated and will be apparent to those skilled in the art that many physical changes, only a few of which are exemplified in the detailed description of the invention, could be made without altering the inventive concepts and principles embodied therein. It is also to be appreciated that numerous embodiments incorporating only part of the preferred embodiment are possible which do not alter, with respect to those parts, the inventive concepts and principles embodied therein. The present embodiments and optional configurations are therefore to be considered in all respects as exemplary and/or illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all alternate embodiments and changes to this embodiment which come within the meaning and range of equivalency of said claims are therefore to be embraced therein.

LIST OF REFERENCE NUMERALS

(37) 1 prior art planetary carrier assembly 2 prior art forged planetary spider 3 prior art balancing holes 4 prior art main planet carrier body 5 prior art spider outer flange 6 prior art planetary plate 7 prior art planet pins 8 prior art planet gears 10 planetary carrier assembly 14 planet carrier body 16 planetary plate 17 corresponding planet pin holes 20 stamped planetary spider 22 planetary spider blank 24 central portion 26A-26D flange portions 28A-28D spider connection legs 29A-29D ends of spider connection legs 30A-30D balance portions 32A-32D inner surfaces of spider connection legs 34 planet pin holes 36 interface 38 balancing holes