Spring devices – Vehicle – Leaf
Patent
1991-04-03
1992-11-10
Graham, Matthew C.
Spring devices
Vehicle
Leaf
267 46, B60G 1104
Patent
active
051617854
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a leaf spring for the suspension of a rigid wheel axle in automotive vehicles, said leaf spring being pivotally but non-displaceably connected at one end thereof to the frame of the vehicle or some like vehicle part and being pivotally connected at the other end thereof also to said frame and the center part of the spring being connected rigidly to said wheel axle.
Springs of this kind are used very widely as rigid wheel-axle suspensions, especially in heavy vehicles, such as lorries, trucks and like vehicles. In this case, one such spring is mounted at each end of the wheel axle, and as seen from the side, at which the load is exerted, the most common of these springs exhibits a convex shape over the major part of its length. When the spring is subjected to load, it will straighten out and increase in length. Because one end of the spring is connected nondisplaceably to the frame of the vehicle, the other end of the spring will be displaced in its longitudinal direction, and consequently it is necessary to connect said other end in a manner which will permit such longitudinal displacement.
The aforesaid increase in length of the spring that takes place when the spring is subjected to load, will also result in linear displacement of the ends of the wheel axle fastened to the center of the spring when the load changes. When there is a difference in movement of the springs on both sides of the vehicle, such linear displacements of the axle will result in steering of the axle in its horizontal plane, which deleteriously affects the steering performance of the vehicle. Furthermore, the connection between said other ends of the springs and the vehicle frame which permits longitudinal movement of the spring creates problems with respect to friction and wear.
The object of the present invention is to overcome the aforesaid problems and to provide a leaf spring of the said kind which will enable the wheel axle to move through very small linear distances, which can be controlled by changing the shape of the spring, when the load on the spring changes and which will permit very small movements of the end of the spring connected to the vehicle frame for longitudinal movement. This object is achieved in accordance with the invention by means of a spring, in which, when no load is exerted thereon, that part of the spring which is located between the first spring end and the center part of the spring is straight or slightly curved, whereas that part of the spring which is located between the center part of the spring and the other end of the spring has a double-curve configuration and, seen from the side, where the load on the center part attacks, has a downwardly convex part nearest the center part and a downwardly concave part nearest the other end of the spring and adjoining the downwardly convex part.
The invention will now be described in more detail with reference to the accompanying drawing, in which
FIG. 1 illustrates schematically a known leaf spring and shows the behavior of the spring under different loads;
FIG. 2 illustrates schematically a spring configured in accordance with one embodiment of the invention;
FIG. 3 is a side view of the leaf spring according to one embodiment of the invention and shows the spring in a relaxed state: and
FIG. 4 is a side view of the leaf spring of FIG. 3 fitted to an automotive vehicle.
FIG. 1 illustrates a leaf spring of known kind, one end of which is connected at 2 to the schematically illustrated frame 3 of a vehicle in a manner which will permit pivotal movement of said one end, but not axial movement. The other end of the leaf spring 1 is connected to said frame 3 at a location 4 thereon, said connection being such as to permit said other spring end to pivot and also to move longitudinally. Firmly attached to the center part of the spring 1 is a schematically illustrated vehicle-wheel axle 5.
The full line in FIG. 1 illustrates the configuration of the spring 1 when no load is exerted thereon. When the spring is subjected to load, the s
REFERENCES:
patent: Re3205 (1868-11-01), Buzzell
patent: 433308 (1890-07-01), Saladee
patent: 1135036 (1915-04-01), McIntyre
patent: 1155062 (1915-09-01), Heisler
patent: 1240929 (1917-09-01), Bissell
patent: 1324440 (1919-12-01), Ackerman
patent: 1330923 (1920-02-01), Utz
patent: 1458912 (1923-06-01), Draver
patent: 1583003 (1926-05-01), Miller
patent: 3685812 (1972-08-01), Buchesky et al.
patent: 3891197 (1975-06-01), Poulos
Ingvarsson Henrik
Svensson Roland
AB Volvo
Graham Matthew C.
LandOfFree
Leaf spring does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Leaf spring, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Leaf spring will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2288933