Patent Application
20150219196
The invention relates generally to a damper cover plate connection in a torque converter, and more specifically to a damper cover plate connection with press fit riveting.
U.S. Patent Publication No. 2011/0088992 hereby incorporated by reference herein, describes a clutch assembly including a rivet having a head disposed between a leaf spring and a cover with a shaft in the piston plate hole. The piston plate or the cover is deflectable to clamp the rivet head between the cover and the piston plate before the shaft is expanded.
U.S. Pat. No. 8,328,647, hereby incorporated by reference herein, describes a cover or piston plate having leaf spring connections with gripping segments where the cover or piston plate is deflectable and a portion of the connection may include a rivet.
To assemble a torque converter it is known to use conventional rivets as a means of connection for components such as the damper assembly and the turbine. Prior methods of assembly require sufficient access through the damper plate to perform the upsetting operation. The access holes are required to accommodate the riveting tool punch size, clearance to stripper, stripper size, and clearance to damper. To accommodate this reduces the degrees of freedom for positioning and size of the damper springs, thereby, adversely affecting damper rate.
Press fit rivets are not known to be used in torque converters, especially between a damper cover plate and a turbine.
Example aspects broadly comprise a damper assembly for a torque converter comprising: a cover plate comprising a hole having a first diameter; a press fit rivet disposed in the hole, the rivet including: a rivet head and a press fit portion having a second diameter; where prior to press fitting the rivet into the hole, the second diameter is greater than the first diameter. In an example aspect, the damper assembly includes a flange having an access hole aligned with the rivet head. In an example aspect, the cover plate includes an inner surface facing the flange and an outer surface opposite the inner surface, and wherein the rivet head is disposed at the inner surface.
Other example aspects broadly comprise a torque converter comprising the damper assembly as described and a turbine having a turbine shell, wherein the rivet connects the cover plate and the turbine shell. In an example aspect, the torque converter further comprises a turbine hub, wherein the rivet connects the cover plate, the turbine shell, and the turbine hub.
Other example aspects broadly comprise a torque converter comprising: a turbine including a shell having a first hole and a first diameter; a damper assembly including: a flange including an access hole; a cover plate disposed between the turbine shell and the flange; the cover plate comprising a thickness and a second hole with a second diameter; and, a press fit rivet including: a preformed head aligned with the flange access hole; a press fit portion extending from the preformed head and disposed in the cover plate second hole, the press fit portion having a third diameter equal to the second diameter and a length at most equal to the cover plate thickness; a body portion installed in the first hole and having a fourth diameter equal to the first diameter and at most equal to the second diameter; and, an upset portion disposed at a distal end of the press fit rivet opposite the preformed head and having a fifth diameter larger than the fourth diameter. In an example aspect, the damper cover plate includes an inner surface and an outer surface, and wherein the rivet head is disposed at the inner surface. In an example aspect, the rivet connects the cover plate and the turbine shell. In an example aspect, the torque converter further comprises a turbine hub, wherein the rivet connects the cover plate, the turbine shell, and the turbine hub. In an example aspect, the torque converter includes, prior to press fitting the rivet into the hole, the upset portion has a diameter at most equal to the second diameter.
Other example aspects broadly comprise a method of connecting a damper assembly and a turbine for a torque converter comprising: providing a press fit rivet having: a rivet head, a press fit portion having a first diameter, a body portion having a second diameter, where the second diameter is at most equal to the first diameter; an upset portion, and an opposite end; providing a damper assembly including a cover plate having a hole having a third diameter, where the third diameter is less than the first diameter; press fitting the press fit portion of the rivet into the hole; providing a turbine including a turbine shell having a positioning hole having a fourth diameter; where the fourth diameter is at least equal to or greater than the second diameter; aligning and assembling the positioning hole of the turbine shell onto the rivet; and expanding the upset portion of the rivet into the positioning hole by upsetting the opposite end of the rivet.
In an example aspect, the method includes where the damper assembly further includes a flange having an access hole, and the step of providing a damper assembly further includes aligning the flange access hole with the rivet head. In an example aspect the method includes where the cover plate includes an inner surface and an outer surface, and wherein the rivet head is disposed at the inner surface. In an example aspect, the method includes where the step of aligning and assembling further comprises providing a turbine hub having an opening, and aligning and positioning the opening of the turbine hub onto the rivet prior to the step of expanding. In an example aspect, the method includes where the step of expanding the upset portion of the rivet includes providing upsetting punch and stripper tools and positioning the upsetting tools over the opposite end of the rivet prior to upsetting. In an example aspect, the method includes where the step of providing a damper assembly further includes assembling the damper assembly including springs, radially outward springs, the damper flange, the damper cover plate, and outer sheet metal rivets.
The nature and mode of operation of the present invention will now be more fully described in the following detailed description of the invention taken with the accompanying drawing figures, in which:
At the outset, it should be appreciated that like drawing numbers appearing in different drawing views identify identical, or functionally similar, structural elements. Furthermore, it is understood that this invention is not limited only to the particular embodiments, methodology, materials and modifications described herein, and as such may, of course, vary. It is also understood that the terminology used herein is for the purpose of describing particular aspects only, and is not intended to limit the scope of the present invention, which is limited only by the appended claims.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this invention belongs. Although any methods, devices or materials similar or equivalent to those described herein can be used in the practice or testing of the invention, the following example methods, devices, and materials are now described.
The following description is made with reference to
Torque converter 10 includes piston 14, clutch plate 38, drive plate 54, and cover plates 42, 50, and 52. Outer sheet metal rivet 51 connects cover plates 42 and 52. Leaf springs 58 connect drive plate 54 and piston 14. Torque converter 10 further includes damper hub 56 and damper assembly 40 including cover plate 42, springs 46, radially outward springs 47, flange 48, and press fit rivet 60. Damper assembly 40 is connected to and drivable by turbine 20, and is positioned between turbine 20 and front cover 12. Damper assembly 40 may be advantageously preassembled to include press fit rivet 60. In a particular aspect, rivet 60 is press fit to connect to damper cover plate 42. Rivet 60 further connects damper assembly 40 to turbine shell 22 and turbine hub 26. Press fit rivet 60 is positioned so that the preformed head 62 of rivet 60 is toward the damper. In the prior art, conventional riveting is employed wherein the rivet head is disposed toward the turbine to ease installation of the rivet. That is, it is easier to install the rivet from the turbine side than to guide the rivet through the damper flange. Thus, the prior art requires access through the damper assembly to accommodate upsetting tooling and operation. Torque converter 10 further includes bearings 86, inner race 88, and roller 92 for one-way clutch 30. Cover pilot 90 is shown in
Press fit rivet 60, in an example aspect, is shown in greater detail in
In an example embodiment, press fit rivet 60 is disposed into cover plate hole 44 having diameter d4 using force so that press fit portion 64 fits snugly into hole 44. After press fitting operation, press fit portion 64 includes (i) a length (65 in
In an example aspect, as a result of the press fit operation, the diameter of press fit portion 64 is decreased. In other words, the original diameter dl of press fit portion is reduced. Prior to press fitting, press fit portion 64 includes diameter d1 (from
In an example aspect, damper assembly 40 for torque converter 10 comprises: cover plate 42 comprising hole 44 having a first diameter d4; press fit rivet 60 disposed in hole 44, the rivet including: rivet head 62 and press fit portion 64 having a second diameter d1; where prior to press fitting the rivet into the hole, the second diameter is greater than the first diameter. In an example aspect, the damper assembly includes flange 48 having access hole 49 aligned with rivet head 62. In an example aspect, cover plate 42 includes inner surface 41 and outer surface 43, and wherein rivet head 62 is disposed at inner surface 41. In an example aspect, the damper assembly connects to a torque converter including turbine 20 having turbine shell 22, wherein rivet 60 connects cover plate 42 and turbine shell 22. In an example aspect, the torque converter further comprises turbine hub 26, wherein rivet 60 connects cover plate 42, turbine shell 22, and turbine hub 26.
In an example aspect, torque converter 10 comprises: turbine 20 including shell 22 having first positioning hole 24 and first diameter d5; damper assembly 40 including: flange 48 including access hole 49; cover plate 42 disposed between turbine shell 20 and flange 48; cover plate 42 comprising a thickness 45 and second hole 44 with second diameter d4; and, press fit rivet 60 including: preformed head 62 aligned with flange access hole 49; press fit portion 64 extending from preformed head 62 and disposed in cover plate second hole 44, press fit portion 64 having a third diameter d1 equal to the second diameter and length 65 at most equal to the cover plate thickness 45; body portion 66 installed in the first and second holes and having fourth diameter d2 equal to the first diameter and at most equal to the second diameter; and, upset portion 64 disposed at a distal end 70 of press fit rivet 60 opposite preformed head 62 and having a fifth diameter d6 larger than the fourth diameter in the post-upsetting condition. In an example aspect, damper cover plate 42 includes inner surface 41 and outer surface 43, and wherein rivet head 62 is disposed at inner surface 41. In an example aspect, rivet 60 connects cover plate 42 and turbine shell 20. In an example aspect, torque converter 10 further comprises turbine hub 26, wherein rivet 60 connects cover plate 42, turbine shell 22, and turbine hub 26. In an example aspect, prior to press fitting the rivet into the hole, upset portion 64 has a diameter at most equal to second diameter d4.
In an example aspect, a method of connecting a damper assembly and a turbine for a torque converter is provided. Referring to
In an example aspect, the method includes a damper assembly including flange 48 having access hole 49, and where step (ii) of providing a damper assembly further includes aligning flange access hole 49 with rivet head 62 about an axis A. In an example aspect, access hole 49 need only be large enough to accommodate a support for the rivet head. Advantageously, due to the small flange access hole, larger damper size is afforded in an example aspect. Upsetting tools, requiring more clearance, are not inserted into the flange access hole. In an example aspect, the method includes where step (ii) of providing a damper assembly further includes assembling the damper assembly including springs 46, radially outward springs 47, damper flange 48, damper cover plate 42, and outer sheet metal rivets 51.
In an example aspect, the method includes where cover plate 42 includes inner surface 41 and outer surface 43, and wherein rivet head 62 is disposed at inner surface 41. Advantageously, the rivet head is disposed toward the damper.
In an example aspect, the method includes where step (iv) of aligning and assembling further includes providing turbine hub 26 having opening 29, and aligning and positioning opening of the turbine hub onto the rivet prior to the step of expanding.
In an example aspect, the method includes where step (v) of expanding upset portion 68 of rivet 60 includes providing upsetting punch and stripper tools and positioning the upsetting tools over opposite end 70 of the rivet prior to upsetting.
Of course, changes and modifications to the above examples of the invention should be readily apparent to those having ordinary skill in the art, without departing from the spirit or scope of the invention as claimed. Although the invention is described by reference to specific preferred and/or example embodiments, it is clear that variations can be made without departing from the scope or spirit of the invention as claimed.
| Number | Date | Country | |
|---|---|---|---|
| 61936544 | Feb 2014 | US |
