The present invention relates to an adjuster mechanism and more particularly to an adjuster mechanism for use in adjusting a spring preload such as for an off road vehicle (ORV) or all terrain vehicle (ATV).
Suspension systems in vehicles are commonly subjected to varying road conditions. This is especially true in ORVs, ATVs, snowmobiles, and the like. These vehicles may have adjustable suspension systems to accommodate the preferences of the vehicle operator on irregular terrain. Known systems that allow for one remote adjuster for all shock absorbers have been directed toward adjustment of the internal pressure of the shock absorber, as opposed to an external preload cylinder.
Preload cylinders have been connected to, and are typically concentric with, shock absorbers for adjusting the spring preload of the shock absorber assembly. The preload cylinder may support a suspension spring associated with the shock absorber. Adjustment of the preload cylinder varies the load placed on the suspension springs thus increasing or decreasing the suspension load carrying capacity. A desired ride comfort level, provided by the suspension ride height, varies from operator to operator. For example, the weight of the operator affects the performance of the suspension system. The effect of varying weight is especially noticeable on the performance of suspension systems in smaller vehicles like snowmobiles and ATVs.
Many systems have the ability to adjust the suspension while the vehicle is in operation by providing an adjustment mechanism within reach of the operator. In one proposed adjustment system for a motorcycle there are two shock absorbers which are adjustable through a single control. This system uses a compressible fluid. The compressible fluid in the prior art system would allow fluid to flow from one shock absorber to another when a force is applied to one side of the vehicle. That is, the compressible fluid will not resist the force.
Accordingly, it is desirable to provide a suspension adjustment system which allows for equal preload adjustment.
The suspension system according to the present invention provides a system for making equal adjustments to a plurality of preload cylinders.
The suspension system includes multiple shock absorbers and corresponding preload cylinders. The height of the preload cylinders is adjustable by a lever attached to an adjuster mechanism. The adjuster mechanism is within reach of a vehicle operator for easily changing the suspension height while the vehicle is in operation. Changes to the position of the adjuster mechanism will correspondingly adjust the position of all the preload cylinders and thus vary the spring preload of a spring associated with the shock absorber.
As disclosed, there are at least two shock absorbers and preload cylinders connected to an adjuster mechanism. Changes in the adjuster mechanism will affect all preload cylinders equally. Thus, only one adjuster mechanism is needed. The system may be used on front and/or rear shock absorbers.
The system has incompressible fluid within the adjuster mechanism. The incompressible fluid ensures that a force on one side of the vehicle will be resisted by the suspension on the other side of the vehicle.
The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows:
The preload cylinder 18, shown in
A lower wall 26 of the internal chamber 34 is supported by a dimple 27 extending from the shock absorber housing 20. The outer wall 30 extends down, past the lower wall 26. This allows the size of the preload cylinder 18 to be adjusted without allowing fluid leakage and pressure loss to the internal chamber 34. The upper surface 28 of the preload cylinder 18 supports the coil spring 22.
An adjuster mechanism 38 is shown in
Adjusting a lever 42 changes the position of the adjuster mechanism 38 resulting in an increase or decrease the amount of fluid that is in the preload cylinder 18. The adjuster mechanism 38 includes a fluid reservoir 43. Moving lever 42 will cause a first mechanism arm 45 to pivot about fixed pivot 41, which in turn causes a second mechanism arm 47 to pivot. As the first and second mechanism arms 45 and 47 pivot, a reservoir piston 49 moves inwardly or outwardly of reservoir 43. The change in the position of reservoir piston 49 will increase or decrease the amount of hydraulic fluid in the fluid reservoirs 43. As mentioned, fluid reservoir 43 is fluidly connected to the internal chamber 34 of the preload cylinders 18 by fluid line 40. Thus, by moving the lever 42, the relative amount of fluid in the internal chambers 34 can be varied. As the fluid in the internal chambers is varied, the position of wall 30 changes and hence the length of spring 22 changes.
Because the preload chambers 34 are connected hydraulically by the fluid line 40, fluid pressure remains constant across both chambers resulting in a balanced preload force between the two chambers. Fluid will transfer from one chamber 34 to the other connected chamber 34 in order to keep pressure equal, and the total fluid volume in both chambers 34 plus the fluid line 40 will remain constant. Therefore the amount of preload cylinder stroke available in the assembly 18 must be limited so as not to allow excessive displacement difference between one side and the other connected assemblies 18, the amount which depends on the specific vehicle application. In addition, the size of the cross sectional flow area of the fluid line 40 can be designed to control the speed at which the connected chambers 34 can equalize, preventing sudden bumps from offsetting the vehicle.
A scale 48 is used to designate an appropriate position for lever 42 given a particular load on the suspension system. For example, scale 48 may have detents given in weight increments. Thus, a system operator may adjust the setting to reflect the payload that will be placed on the suspension system. The payload setting may be the passenger's weight, for example. The adjuster mechanism 38 then makes the appropriate adjustments to reflect the change. The embodiment shown utilizes a lever and scale display. However, it should be known that an electronic control and display may be used as well.
Of course, a user may determine that a position on the scale higher or lower than the user's actual weight may be most desirable given the particular ride height level the user would like. However, the scale setting based upon weight would provide that user with the ability to make an intelligent choice to begin the process of selecting the desired position.
The adjuster mechanism 38 may be attached to two shock absorbers 12. Alternatively, the system may be used with all of the shock absorbers on the vehicle.
The foregoing description is exemplary rather than defined by the limitations within. Many modifications and variations of the present invention are possible in light of the above teachings. The preferred embodiments of this invention have been disclosed, however, one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. For that reason the following claims should be studied to determine the true scope and content of this invention.
The present invention is a continuation-in-part of U.S. patent application Ser. No. 10/463,162, filed Jun. 17, 2003.
Number | Date | Country | |
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Parent | 10463162 | Jun 2003 | US |
Child | 11145729 | Jun 2005 | US |