Flow forming connection of metallic parts and resultant part assembly
A method and apparatus (10) provide a flow formed part assembly (12) having mechanically interlocked first and second metallic parts (22) and (24).
Latest TransForm Automotive LLC Patents:
- Vehicle drivetrain assembly and method for making the assembly
- Vehicle drivetrain assembly and method for making the assembly
- VEHICLE DRIVETRAIN ASSEMBLY AND METHOD FOR MAKING THE ASSEMBLY
- Method for roll-forming disk carriers or the like and the associated profile roller set
- Method for making vehicle axle differential casing and resultant product
1. Field of the Invention
This invention relates to a method and apparatus for mechanically connecting metallic parts to each other by flow forming and also relates to the resultant part assembly.
2. Background Art
Metallic parts utilized in torque transmission such as vehicle transmissions, transfer cases, couplings and other torque transmitting assemblies have previously been made as individual parts by flow forming which involves rotating a part around a central axis about which one or more rotary flow forming tools are rotated and moved axially to form the part about a central mandrel.
Prior art references noted during an investigation conducted in accordance with the present invention include U.S. Pat. Nos.: 2,707,823 Sowter; 2,707,824 Sowter; 2,894,323 Sowter et al.; 2,926,030 Rozmus et al.; and 3,090,116 Burgess.
SUMMARY OF THE INVENTIONOne object of the present invention is to provide an improved method for mechanically connecting metallic parts to each other.
In carrying out the above object, the method for mechanically connecting metallic parts to each other in accordance with the invention is performed by rotating first and second metallic parts with each other about a central axis with the first metallic part having an outer locking formation. A flow forming tool is rotated about a tool axis at a location spaced radially outward from the central axis, and the rotating flow forming tool is moved axially along the central axis to flow form the second metallic part around the first metallic part in a mechanically interlocking relationship with the outer locking formation of the first metallic part.
The outer locking formation of the first mechanical part as disclosed includes circumferentially spaced locking projections about which the second metallic part is flow formed to provide both circumferential and axial mechanical interlocking of the parts to each other.
The first and second metallic parts may be made of different types of metals, have different heat treatments, have different compositions, have blanks made by different processes or combinations of the former.
A plurality of flow forming tools may be rotated about associated axes that are spaced radially outward from the central axis, and the rotating flow forming tools are moved together axially along the central axis to provide the flow forming of the second metallic part around the first metallic part in its mechanically interlocking relationship with the outer locking formation of the first metallic part.
Another object of the present invention is to provide improved apparatus for mechanically connecting metallic parts to each other.
In carrying out the immediately preceding object, the apparatus for mechanically connecting metallic parts to each other in accordance with the invention includes a spindle for rotatably mounting first and second metallic parts about a central axis with the first metallic part having an outer locking formation. A flow former includes at least one rotary flow forming tool mounted for rotation about a tool axis at a location spaced radially outward from the central axis. The flow forming tool is mounted for axial movement along the central axis during the rotation thereof to flow form the second metallic part around the first metallic part in a mechanically interlocking relationship with the outer locking formation of the first metallic part.
The spindle of the apparatus includes a mandrel and a tailstock between which the first and second metallic parts are axially clamped and supported for the rotation about the central axis.
The apparatus may be constructed with the flow former including a plurality of flow forming tools that are rotated about associated axes spaced radially outward from the central axis and that are moved axially along the central axis to provide the flow forming of the second metallic part around the first metallic part.
Another object of the present invention is to provide an improved metallic part assembly.
In carrying out the immediately preceding object, the metallic part assembly of the invention includes a first metallic part that has a central axis and an outer locking formation including locking projections extending outwardly from and spaced about the central axis. A second metallic part of the assembly is flow formed around the outer locking formation of the first metallic part and located on opposite axial sides and circumferentially between the locking projections so as to mechanically interlock the first and second metallic parts to each other.
The first and second metallic parts may be made of different metals, have different heat treatments, have different compositions, start with blanks made by different processes, or have combinations of the former.
The objects, features and advantages of the present invention are readily apparent from the following detailed description of the preferred embodiment for carrying out the invention when taken in connection with the accompanying drawings.
With reference to
As shown in
The first metallic part 22 as shown in
As shown in
More specifically as shown in
The first and second metallic parts 22 and 24 may be made from different types of metals such as steel, zinc, aluminum, etc., may have different heat treatments to provide the required properties for each part, may have different compositions to also provide the required properties for each part, may be formed from blanks made by different processes such as rolling, casting, forming and machining, and may be combinations of the former.
As shown in
While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.
Claims
1. A method for mechanically connecting metallic parts to each other, comprising:
- rotating first and second metallic parts with each other about a central axis with the first metallic part having an outer locking formation; and
- rotating a flow forming tool about a tool axis at a location spaced radially outward from the central axis; and
- moving the rotating flow forming tool axially along the central axis to flow form the second metallic part around the first metallic part in a mechanically interlocking relationship with the outer locking formation of the first metallic part.
2. A metallic part flow forming connecting method as in claim 1 wherein the outer locking formation of the first mechanical part includes circumferentially spaced locking projections about which the second metallic part is flow formed to provide both circumferential and axial mechanical interlocking of the parts to each other.
3. A metallic part flow forming connecting method as in claim 1 wherein the first and second metallic parts are selected from the group consisting of: parts made of different types of metals; parts having different heat treatments; parts having different compositions; parts made from blanks made by different processes; and combinations thereof.
4. A metallic part flow forming connecting method as in claim 1 wherein a plurality of flow forming tools are rotated about associated axes at a location spaced radially outward from the central axis, and the rotating flow forming tools being moved together axially along the central axis to provide the flow forming of the second metallic part around the first metallic part in its mechanically interlocking relationship with the outer locking formation of the first metallic part.
5. A method for mechanically connecting metallic parts to each other, comprising:
- initially forming a first metallic part with an outer locking formation including locking projections spaced circumferentially and extending outwardly from a central axis;
- rotating the first metallic part and a second metallic part with each other about the central axis;
- rotating a flow forming tool about a tool axis at a location spaced radially outward from the central axis; and
- moving the rotating flow forming tool axially along the central axis to flow form the second metallic part around the circumferentially spaced locking projections of the outer locking formation of the first metallic part in an axial and rotationally mechanically interlocking relationship.
6. Apparatus for mechanically connecting metallic parts to each other, comprising:
- a spindle for rotatably mounting first and second metallic parts about a central axis with the first metallic part having an outer locking formation; and
- a flow former including at least one rotary flow forming tool mounted for rotation about a tool axis at a location spaced radially outward from the central axis; and the flow forming tool being mounted for axial movement along the central axis during the rotation thereof to flow form the second metallic part around the first metallic part in a mechanically interlocking relationship with the outer locking formation of the first metallic part.
7. Apparatus for mechanically connecting metallic parts as in claim 6 wherein the spindle includes a mandrel and a tailstock between which the first and second metallic parts are axially clamped and supported for the rotation about the central axis.
8. Apparatus for mechanically connecting metallic parts as in claim 6 wherein the flow former includes a plurality of flow forming tools that are rotated about associated axes at a location spaced radially outward from the central axis and that are moved axially along the central axis to provide the flow forming of the second metallic part around the first metallic part.
9. A metallic part assembly comprising:
- a first metallic part having a central axis and an outer locking formation including locking projections extending outwardly from and spaced about the central axis; and
- a second metallic part that is flow formed around the outer locking formation of the first metallic part and located on opposite axial sides and circumferentially between the locking projections so as to mechanically interlock the first and second metallic parts to each other.
10. A metallic part assembly as in claim 9 wherein the first and second metallic parts are selected from the group consisting of: parts made of different types of metals; parts having different heat treatments; parts having different compositions; parts made from blanks made by different processes; and combinations thereof.
Type: Application
Filed: Jul 19, 2006
Publication Date: Jan 24, 2008
Applicant: TransForm Automotive LLC (Sterling Heights, MI)
Inventor: Thomas Meier (Rochester Hills, MI)
Application Number: 11/488,959
International Classification: B21D 39/00 (20060101); B21D 22/00 (20060101);