The invention relates to a side part of a frame of a vehicle seat, namely to a seat frame side part or a side part of a seat back frame.
Such a side part or frame side part has been known from EP 233 822 B1. Similar frame side parts are also shown in the following documents: U.S. Pat. No. 6,264,275, EP 1 190 894 B1, U.S. Pat. No. 6,276,650 and DE 44 19 139 C2.
The frame side part should on the one side be capable of taking high loads, in particular crash loads, on the other side, it should have as little weight as possible. It has to perform its function as a structure element; usually, at least one rocker is articulated to the seat frame part, said rocker being in turn hinge-linked to a longitudinal guide. On side parts of a seat back frame, there is usually provided a bearing hole for a seat back hinge or for a connection to a hinge arm of a seat back hinge. Accordingly, discrete regions of the frame side part are specially formed to perform a function of bearing, of connecting to other parts or of retaining other parts.
In view thereof, the invention develops a frame side part of a motor vehicle seat in such a manner that it has a lower weight than a comparable prior art component at increased or at least equal strength. Accordingly, the invention develops the frame side part of the type mentioned herein above for it to have a lower overall weight at at least equal strength.
In view of the previously known frame side part of the type mentioned herein above, the solution to this object is that the frame side part is built in layers, having at least two layers, that one layer is a sheet steel part determining the shape of the frame side part and that a second layer is a reinforcing member having a material thickness in the y direction that is greater than the material thickness of the sheet steel part.
This frame side part is built in layers or in a sandwich style. It has at least two layers, these two layers being made from different materials. A sheet steel part is still provided. The sheet steel part determines the shape of the frame side part. It has similarities with the sheet steel part used in prior art. But compared to the prior art sheet steel part, it may now be thinner and also of a lighter weight. It is stiffened by the reinforcement body, which forms the second layer. The reinforcement body may also be made from a light-weighted material such as a plastic material. The reinforcement body usually has in the y direction a thickness that is much greater, for example at least 5 times, preferably at least 10 times greater than the material thickness of the sheet steel part. Preferably, the reinforcement body is provided with recesses and/or perforations in order to save weight. It preferably has a mesh structure, in particular when viewed in the y direction.
The sheet steel part, meaning the first layer, is configured for meeting in principle all the mechanical demands placed on the frame side part. The strength however is insufficient. Sufficient strength is only achieved upon assembling it with the reinforcement body. Said reinforcement body substantially is a passive body, which reinforces the sheet steel part where reinforcement is needed to achieve sufficient strength. The reinforcement body may however also form bearing areas, preferably forming thin bearing rings that are mechanically supported by the sheet steel part.
A layered construction with three layers is preferred. Either a reinforcement body is sandwiched between the sheet steel part and another sheet steel part or there are two reinforcement bodies on either side of a sheet steel part. Thanks to the layered construction, one obtains very far reaching possibilities that can be used on purpose for the combined part to be configured to meet the respective mechanical demands. It is possible to use a sheet steel material that is much thinner than that used in prior art, highly resistant sheet steel being preferably utilized.
Usually, the frame side parts of the invention are portions of a substantially square frame. The at least one frame cross member extending in the y direction and needed therefore is connected to the frame side parts, the connection occurring at the sheet steel part. Preferably, the reinforcement bodies do not extend into the region of connection with the cross members.
An advantage of the invention is that now the sheet steel parts need no longer be deformed to the same extent as the prior art frame side parts. In prior art, attempts have been made to provide the frame side part with high strength by giving it a profile as clear as possible and by deforming it significantly. Deformation however has its limits. With the solution of the invention, strong deformation is no longer necessary; the additional reinforcement body favorably stiffens the frame side part. Accordingly, the invention cuts a new path.
In a preferred development, the sheet steel part is made from a piece of sheet steel of various thicknesses and/or of various material qualities. What are referred to as “tailored blanks” are intended to be utilized in particular. The material under discussion is an industrially made sheet steel material that is in the form of a coil for example; it has various thicknesses, and is for example in the form of strips of various thicknesses.
In an exemplary embodiment the reinforcement body is made from a material having a lower specific weight than the metal from which said sheet steel part is made, the difference being at least 50%. Preferably the sheet steel part has a wall thickness of less than 1.5 mm, and is made from highly resistant sheet steel having yield strength of more than 800 N/mm2. Preferably said reinforcement body is made from a material having a lower specific weight than the metal from which said sheet steel part is made, the difference being at least 100%.
Other features and advantages will become more apparent upon reviewing the appended claims and the following non restrictive description of embodiments of the invention, given by way of example only with reference to the drawing. In said drawing:
In a known way, the vehicle seat shown in
Herein after, the first exemplary embodiment will be described in accordance with the
A second layer is formed by a reinforcement body 26 that is made from a plastic material in the instant case, and may be a prefabricated, shaped part. It has a large number of recesses and of perforations in order to be light-weighted. It is made by injection molding. Its material thickness across the y direction is considerably thicker than the thickness of the sheet steel material of the sheet steel part 24, the difference is at least equal to factor 5, preferably to factor 10. Highly resistant sheet steel is used as the material for the sheet steel part 26, the yield strength should be more than 800 N/mm.sup.2, a typical material is DP 1000, the wall thickness ranges from 0.6 to 0.7 mm, and is in any case less than 1 mm. As compared to a prior art frame side part that has no layered structure, considerable weight savings are achieved, said savings being of at least 25%, often of at least 40%. Despite the lighter layered structure a very high stiffness is achieved, the frame side part is more stable than a prior art one-shell frame side part.
The two layers are bonded together according to prior art. For this purpose, the reader is referred to the second exemplary embodiment viewed in the
Sheet steel part 24 and reinforcement body 26 may also be glued or welded together or be joined together in another way. It is also possible for them not to be joined together but to only abut each other. As best shown in
It is possible to retrofit the reinforcement body 26 to the sheet steel part 24 by injection molding it thereon, the sheet steel part 24 being more specifically a constituent part of an injection mould. In this way, an intimate and internal bond is achieved.
The reinforcement body 26 can also be made from another material than plastic material. It may for example also be made from a light-weighted material such as light metal, metal foam, a metal grid structure and so on. The sheet steel can also be zigzag shaped.
In the z direction, the reinforcement body 26 has a length that is significantly smaller than that of the sheet steel part 24, for example only 70% of said length, but in particular falling short of 80% of the length. The corresponding dimension in the x direction is also less. As clearly shown in the
In the third exemplary embodiment shown in
In this third exemplary embodiment, the reinforcement body 26 simultaneously forms a bearing area for a rear rocker 46. For this purpose, it has an annular region 54 that extends through a hole 48 in the two sheet steel parts 24, 44 in the mounted condition. As usual, the rims of these holes 48 determine the mechanical strength of the bearing region, the ring 54 of the reinforcement body 26 ensures favorable bearing properties and fewer losses during sliding friction.
The fourth exemplary embodiment shown in
In the fifth exemplary embodiment according to the
In the sixth exemplary embodiment according to the
Number | Date | Country | Kind |
---|---|---|---|
10 2007 055 602 | Nov 2007 | DE | national |
Number | Name | Date | Kind |
---|---|---|---|
2833339 | Liljengren | May 1958 | A |
3166831 | Keith | Jan 1965 | A |
3602110 | Wiggins | Aug 1971 | A |
3647168 | Eggert et al. | Mar 1972 | A |
3670393 | Almond | Jun 1972 | A |
3815215 | Medawar | Jun 1974 | A |
3866305 | Conn, Jr. | Feb 1975 | A |
4053667 | Smith | Oct 1977 | A |
4350390 | Ogawa | Sep 1982 | A |
4399642 | Bard et al. | Aug 1983 | A |
4433517 | Moore, Jr. | Feb 1984 | A |
4603903 | Moscovitch | Aug 1986 | A |
4889355 | Trimble | Dec 1989 | A |
5015038 | Mrotz, III | May 1991 | A |
5064247 | Clark et al. | Nov 1991 | A |
5100204 | Makihara et al. | Mar 1992 | A |
5326155 | Wild | Jul 1994 | A |
5405178 | Weingartner et al. | Apr 1995 | A |
5445310 | Folmer | Aug 1995 | A |
5924769 | Kao | Jul 1999 | A |
6059369 | Bateson et al. | May 2000 | A |
6096403 | Wycech | Aug 2000 | A |
6131993 | Pesta et al. | Oct 2000 | A |
6142563 | Townsend et al. | Nov 2000 | A |
6149241 | Waku et al. | Nov 2000 | A |
6264412 | Nakamura et al. | Jul 2001 | B1 |
6287666 | Wycech | Sep 2001 | B1 |
6355339 | Sherwood | Mar 2002 | B1 |
6688700 | Gupta et al. | Feb 2004 | B2 |
6857698 | Saberan et al. | Feb 2005 | B2 |
6896324 | Kull et al. | May 2005 | B1 |
7083230 | Kull et al. | Aug 2006 | B2 |
7237846 | Arima | Jul 2007 | B1 |
7250091 | Gupta et al. | Jul 2007 | B2 |
7716797 | Kismarton et al. | May 2010 | B2 |
7954762 | Boren et al. | Jun 2011 | B2 |
20020005621 | Christophliemke et al. | Jan 2002 | A1 |
20040036326 | Bajic et al. | Feb 2004 | A1 |
20040148696 | Clarke | Aug 2004 | A1 |
20040155514 | Talley | Aug 2004 | A1 |
20070026252 | Voit et al. | Feb 2007 | A1 |
20090007326 | Bozic | Jan 2009 | A1 |
20090188100 | Durney et al. | Jul 2009 | A1 |
20100078985 | Mahoney et al. | Apr 2010 | A1 |
20100219674 | Sakkinen et al. | Sep 2010 | A1 |
20110169317 | Fujita et al. | Jul 2011 | A1 |
20120217775 | Fujita et al. | Aug 2012 | A1 |
Number | Date | Country |
---|---|---|
65116 | Nov 1982 | EP |
248240 | Dec 1987 | EP |
2561281 | Sep 1985 | FR |
2890361 | Mar 2007 | FR |
2300434 | Nov 1996 | GB |
WO 8704242 | Jul 1987 | WO |
Number | Date | Country | |
---|---|---|---|
20090127913 A1 | May 2009 | US |