Machine element or mechanism – Gearing – Rotary bodies
Reexamination Certificate
1999-01-21
2001-02-20
Fenstermacher, David (Department: 3682)
Machine element or mechanism
Gearing
Rotary bodies
C074S445000, C074S458000
Reexamination Certificate
active
06189399
ABSTRACT:
FIELD OF THE INVENTION
The invention relates to an adjustment device for motor vehicle seats with a gearing part, which is in gear with an interlocked part of the driving mechanism or the descending force and which comprises a device for a compensation of the backlash between the gearing part and the part of the driving mechanism or the descending force.
BACKGROUND OF THE INVENTION
From the state of the art numerous devices and methods are known to develop and arrange gearing parts, which are in gear with each other in such a way that the tooth gear between them is essentially without backlash. Such adjustment devices, which are embodied in a manner free from backlash are advantageous for the relative movement between two parts of a motor vehicle seat, which are to be adjusted, because undesired backlash is practically excluded and noises caused thereof while driving, for example rattling, or mechanical movements, namely for example trembling of a part are mostly excluded. A zero backlash of the two parts of a motor vehicle seat, which are to be adjusted towards each other via an adjustment device is of a special importance, if the path is relatively long between the adjustment device and the place, where a force can act upon. This is the case for example with adjustment devices for the inclination adjustment of back rests. Here, the back rest is a fairly long lever, even a slight backlash in the joint of the adjustment device has an effect at the end of the back rest over the entire length of the lever.
The possibilities for compensating the backlash for adjustment devices of the kind mentioned here allow a compensation of the backlash over the entire adjustment path, which the two parts to be adjusted move along in a relative manner towards each other. The compensation of the backlash, however, has the disadvantage that the operational forces for the adjustment device also have to have an effect on the compensation for the backlash at the same time, namely moving the same at least partially or surmount it. The adjusting forces are therefore higher than with adjustment devices without a compensation of the backlash. Especially with manual adjustment devices a certain disadvantage is obvious, as higher operational forces are required.
SUMMARY OF THE INVENTION
This is where the invention starts. It is the task of the invention to further develop an adjustment device of the above mentioned kind with a compensation of the backlash in such a way that within the provided adjustment path, which the adjustment device offers, a compensation of the backlash is only provided in such a case, where it is really needed and the essentially easier adjustment practically without a compensation of the backlash is provided at that point where the two parts to be adjusted towards each other via the adjustment device are not in the position of use. Within the entire region of adjustment of the two parts to be adjusted against each other no complete compensation of the backlash is allocated to that kind of the part of the adjusting region, which is normally not permanently adjusted, but only run through when changing the position of the two parts against each other. The respective adjustment movement therefore occurs relatively easily. For the other part of the adjustment path, which usually corresponds to the chosen position of the two parts against each other by a user, a compensation of the backlash is provided, however.
The consequence thereof results in the fact that the backlash can be performed very easily and especially the induction of forces in the compensating part can be simplified. With a device for a compensation of the backlash a compensating part needs to perform some kind of relative movement, which is suitable to compensate an existing backlash. It has to be connected to the main part in such a mechanically safe way that forces may be induced via the same at the same time without the compensation of the backlash getting lost before a transfer of the forces is possible at all.
By the connection according to the invention of the main part and a compensation part via a swiveling axis (as a first connecting part) a first connection between main part and compensation part is developed, which is resistant to high pressure also with regard to the forces with a suitable dimensioning and which is defined in a mechanical manner. The degree of zero backlash of the two parts against each other is restricted to a circular movement based on the connection via the swiveling axis. The same is hereby limited to a small region of the arc of the circle by the piece of elastic means, which is arranged as a second connecting part between the main part and the compensation part.
In the vicinity of the piece of elastic means a larger relative movement of the teeth of the main part and the compensating part against each other is possible than in the vicinity of the swiveling axis. Near the swiveling axis however, practically no compensating movement of the two teeth against each other is possible. That way by a convenient arrangement of the swiveling axis and the piece of elastic means, the total adjustment region of the adjustment device can be divided in such a way that at least one adjustment region with a compensation of the backlash exists and at least one adjustment region with less compensation of the backlash. These different adjustment regions are used in such a way, that the region with a compensation of the backlash corresponds to the normal adjustment while the other region with less zero backlash, which is not complete, is essentially only run through with adjustment movements, it should not keep a stationary adjustment however.
Between the main part and the compensation part a swiveling axis, and only one alone, is provided, between the two at least one piece of elastic means is provided, may be even two, three or more pieces of elastic means, especially in the shape of dowel pins. In a preferred embodiment at least one thrust projects into the plane of the compensation part from the main part and the compensation part has a recess for receiving this thrust, which is preferably limited by arcs of a circle around the swiveling axis. That way, a mechanical allocation and a connection between the main part and the compensation part is achieved without any noticeable impairment of the swiveling path around the swiveling axis within the region preset by the piece of elastic means. The induction of the forces into the compensation part is thereby improved. In a preferred embodiment the recess is provided with a final part for the limitation of the swiveling movement into one direction and a further final part for the limitation of the swiveling movement in the other direction. Thereby the stress of the piece of elastic means beyond the range of elasticity is avoided. In a simple embodiment the recess is circular just like the thrust.
The teeth of the main gearing and the part of the compensation gearing are arranged towards each other in such a way that they essentially overlap each other. The overlap, however, is only more or less complete. As there are regions, where the overlap is nearly complete, this belongs to the adjustment region without a complete compensation of the backlash, and regions with a larger distance of the teeth amongst each other, this belongs to the adjustment region with a compensation of the backlash.
In a preferred embodiment the distance between the swiveling axis and the one piece of elastic means at least, which is preferably embodied as a dowel pin, is chosen as large as possible. Preferably the swiveling axis is arranged closer to the final part of the main gearing and also the part of the compensation gearing than at the other final region of these two gearings, especially the swiveling axis is in direct vicinity of the first-mentioned final region.
REFERENCES:
patent: 5181433 (1993-01-01), Ueno et al.
patent: 5934144 (1999-08-01), Marinkovic
Becker Burckhard
Frohnhaus Ernst-Reiner
Lingner Michael
C. Rob. Hammerstein GmbH & Co. KG
Fenstermacher David
John Lezdey & Assoc
LandOfFree
Adjustment device for motor vehicle seats does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Adjustment device for motor vehicle seats, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Adjustment device for motor vehicle seats will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2596825