Patent Application
20070102854
1. Field of the Invention
The present invention relates generally to vehicle spring suspensions, and, more particularly, to an improved leaf spring suspension device suitable for attachment to vehicle rear suspension springs.
2. Related Art
It is the usual practice to isolate the rear axle of a vehicle from the frame of the vehicle by supporting the axle in a multi-leaf type spring which is suspended between a forward bearing bracket and a rearward spring shackle whereby most imperfections in the road surface can be absorbed by the wheel and the spring construction and not be transmitted to the vehicle passenger compartment through the frame. The multi-leaf type of spring is characterized by a plurality of stacked leafs, usually four or five in number, which decrease in length away from the base or mounting leaf in the form of a truncated triangular configuration. The axle suspension connects to the thickest or highest part of the multi-leaf spring to achieve maximum support.
Occasionally, when a vehicle is utilized to carry especially heavy loads, the existing leaf springs have a tendency to sag or flex sufficiently to wrap-up or permit “bottoming.” Also, upon unusual wear or unusual surface conditions, the existing springs could allow “forward pitch” or “nose dive” of the vehicle, all to the discomfort of the passengers.
In order to enhance the load bearing capabilities of light pickups, trucks, or the like, prior art stabilizing devices have been proposed. Such prior art devices are either made up of a large number of parts, do not adapt easily to preexisting structure or are not totally effective in compensating for heavy loads on the vehicle's suspension system.
In my U.S. Pat. No. 5,992,831, issued Nov. 30, 1999, I disclose a stabilizer for a leaf spring suspension device. U-bolts are used to secure the stabilizing members to the preexisting vehicle multi-leaf member suspension device. Keepers are used on such leaf spring suspension devices to hold the leaves of the multi-leaf spring member. Such U-bolts must not interfere with the keepers holding the multi-leaves together.
In my U.S. Pat. No. 6,158,723, I disclose a U-bolt which can be used to hold a stabilizing spring to the preexisting multi-leaf spring member suspension system of a vehicle without interfering with the keepers retaining the multi-leaves of the multi-leaf spring suspension together.
However, there is a need for taking up the slack and filling in the space between the bottom of the No. 1 leaf spring in these patents and the top of the No. 1 O.E.M. leaf spring. Such a device should be usable with the preexisting U-bolts of such assemblies. By taking up such slack, compression tension is applied to the spring leaves as they contact. This acts as a spreader keeping this group of mounting hardware constantly in tension while preventing rattling and squeaking.
It is an object of this invention to provide a leaf spring suspension device that can be quickly and easily mounted to the preexisting leaf spring suspension of a vehicle which provides compression tension to the spring leaves as they contact.
It is a further object of this invention to provide such an improved leaf spring suspension device which has a relatively low number of parts.
It is another object of this invention to provide a soft controlled ride when a vehicle is not loaded and is provided with the suspension device of the invention while preventing rattling and squeaking of parts.
It is a further object of this invention to carrying out the foregoing objects by maintaining the mounting hardware of the leaf spring suspension constantly in tension.
It is still another object of this invention to provide an improved leaf spring suspension system which enhances the roll stability of the vehicle.
These and other objects are preferably accomplished by providing an improved leaf spring suspension system for a vehicle having spacers between the bottom of the No. 1 leaf spring of the improved leaf spring suspension system and the top of the O.E.M. No. 1 leaf spring of the vehicle. Such spacers apply compression tension to the spring leaves as they contact thus acting as a spreader to keep the mounting hardware constantly in tension and preventing rattling and squeaking of the parts. Such an improvement enhances the roll stability of the vehicle on which the suspension system is mounted.
Referring now to
Brackets 17, 18 each have interconnected spaced legs 172, 173 extending through holes 175 in mounting bracket 176. The terminal ends of legs 172, 173 are threaded receiving thereon threaded nuts 177, 178, respectively. If desired, spring members 11, 14, 15, 16 may be further secured together at generally the middle thereof by a nut and bolt combination (under bracket 176—not shown).
The foregoing has described original equipment found on vehicles having leaf spring suspension systems. In my U.S. Pat. Nos. 5,922,831 and 6,158,723, the teachings of which are incorporated herein, I described a leaf spring suspension device adapted to be mounted to such a preexisting multi-leaf spring suspension system. Such a system includes, as shown in
Suspension device 19 also includes a curved elongated spring member 27 disposed between spring 29 and multi-leaf spring assembly 10. Although only one such member 27 is shown, obviously more than one may be provided, such as the 2 such spring members 27, 28 in my U.S. Pat. Nos. 5,992,831 and 6,158,723.
Member 27 is of a length less than that of spring 29 which is of a unitary length of a leaf of metallic spring material.
Leaf spring suspension device 19 further includes each member 27, 29 being curved at the middle to form a U-shaped raised portion above the preexisting spring member 11. Members 27, 29 have ends which curve away from member 11 and a pair of threaded U-bolts or brackets 33, 34, couple all members 29, 27, 11, 15, 14 and 16 together. The threaded legs thereof extend through aligned holes 35′ in spaced plates 35, 36 and are secured thereto by nuts 37, 37′. Thus, U-bolts 33, 34, and plates 35, 36 provide bracket means for securing the springs together. Curved member or spring 27 abuts against spring 29 and is slightly less in overall length.
The assembly of parts in
As particularly contemplated in the present invention, and shown more particularly in
Spacer assembly 100 (
Spacer assembly 100 thus abuts at top against the underside 107 of the groove in curved end 21 of leaf spring 29 and the upper surface 108 of spring 11. Spacer assemblies 100 are provided on each side of the assembly as seen in
Thus, the spacer assemblies take up the slack between spring 29 and 11 and fill the space between the bottom or underside 107 of the groove in curved end 21 of leaf spring 29 and the top surface 108 of the O.E.M. leaf spring 11. The spacer assemblies 100 are retained in position using the existing nuts, brackets, bolts, etc. of such leaf spring kits.
Although the spacer assemblies can be of any suitable material, one piece polyurethane is preferred. The spacer assemblies 100 apply compression tension to the spring leaves as they contact. The spacer assemblies act as spreaders to keep the mounting hardware constantly in tension and prevent rattling and squeaking. Such spacer assemblies enhance the roll stability of the vehicle by bringing into play the non-O.E.M. springs opposing tension spring rate.
Although a specific embodiment of the invention is disclosed, variations thereof may occur to an artisan and the scope of the invention should only be limited by the scope of the appended claims.
