Patent Application
20130106038
Embodiments of the invention relate to a vehicle suspension system. Specifically, embodiments of the invention relate to a spring plate that enables spring coil height adjustment in the vehicle suspension system.
Vehicles use a suspension system including a shock absorption system to cushion the ride of the vehicle. The suspension system couples the wheel spindle assembly to the vehicle body such that the wheel spindle assembly can move independent of the vehicle body to avoid transmitting the jostling of the wheel spindle assembly to the vehicle body. The vehicle suspension system includes a set of shock absorbing devices to absorb the energy of the wheel spindle assembly.
The vehicle suspension system includes a set of springs that isolate the vehicle body from the vibrations of the wheel spindle assembly. These springs have a range of motion to provide a separation between the movement of the wheel spindle assembly and the vehicle body. Travel along this range of the spring's motion is dampened by a set of hydraulic valves referred to herein as shock absorbers. The exact loads of the springs and resistance provided by the shock absorbers are design considerations that influence the handling and ride of the vehicle.
In many suspension systems, the shock absorbers are directly connected with the springs and are part of an assembly that defines the spring height, amongst other characteristics of the vehicle suspension system. In these suspension systems the shock absorber is coaxially located within the spring. The springs are often coiled or helical. The shock absorber includes an upper mount that is attached to a stop plate and a lower mount that is attached to the wheel spindle assembly. A spring seat is a plate or flange attached along the length or at one end of the shock absorber. The spring is disposed between the spring seat and the stop plate. The placement of the spring seat relative to the stop plate then determines the spring height. The shock absorber can define a set of attachment points for the spring seat to provide adjustability to the spring height. However, this increases the complexity of the vehicle suspension system and the likelihood of failure due to improper adjustment of the spring seat when adjusting the spring height, especially for individuals without extensive experience with the adjustment mechanism and vehicle suspension system.
The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that different references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.
In the following description, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In other instances, well-known circuits, structures and techniques have not been shown in detail in order not to obscure the understanding of this description. It will be appreciated, however, by one skilled in the art, that the invention may be practiced without such specific details. Those of ordinary skill in the art, with the included descriptions, will be able to implement appropriate functionality without undue experimentation.
The spring 103 can be any size, weight and rate of spring. The spring 103 can have a coiled, helical or similar shape defining an interior channel through which a shock absorber can be disposed to dampen the travel of the spring within the spring's range of motion. The size, shape, weight and rate of the spring can be selected for a vehicle suspension system based on the typical load of the associated vehicle and the desired handling and ride characteristics. The spring 103 can be formed from any metal or alloy with appropriate elastic qualities and similar properties for forming a torsion spring.
The shock absorber 109 can be any type of shock absorber including a hydraulic or pneumatic shock absorber. The shock absorber 109 can include a cylindrical body containing a fluid or gas, a piston head and valves that provide dampening for the attached spring 103. The shock absorber 109 can have a unitary cylindrical exterior or can have separate segments such as an upper and lower reservoir.
The shock absorber 109 can include an upper mount 105 or be attached to an upper mount 105 through a piston 107. The upper mount 105 can be attached to or include a stop plate 101 and can include an attachment mechanism for bolting or similarly attaching the shock absorber 109 and spring 103 to a vehicle body. The shock absorber 109 can also include a lower mount 113. The lower mount 113 can include an attachment mechanism for coupling the shock absorber 109 to a wheel spindle assembly. The attachment mechanism can include a set of pins or similar attachment mechanism.
The shock absorber 109 can also define an attachment mechanism along the length of its cylindrical body for engaging the spring seat 111. The attachment mechanism can be a lip, flange, clip or similar engagement mechanism for interfacing with the spring seat 111. The spring seat 111 can include a complementary attachment mechanism that engages the attachment mechanism of the shock absorber 109 such as a collar, ring, lip, flange, clip or similar engagement mechanism.
The spring seat 111 can be a cylindrical device designed to be coaxially disposed over the shock absorber 109 and to engage the shock absorber 109 with an attachment mechanism defined within the interior channel of the spring seat 111. The spring seat 111 can be a molded, extruded, milled or similarly crafted article. The spring seat 111 can be formed from any metal, metal alloy or similar material with sufficient material strength to carry the load of the spring and vehicle. The spring seat 111 can also define an external flange or similar attachment mechanism for engaging the spring 103 and thereby defining a height of the spring 103 that limits the travel of the spring in combination with the stop plate 101.
The spring seat 111 and its internal attachment mechanism are reversible. The spring seat 111 can engage the shock absorber 109 in either orientation. Each orientation of the spring seat 111 provides a different spring height due to an offset between the location of the internal attachment mechanism that engages the shock absorber 109 and the location of the external flange that engages the spring 103. These two attachment mechanisms are not concentric and are offset along the length of the spring seat 111. The distance between the two attachment mechanisms and the resulting differences in spring height can range from 0.25 inches to four inches depending on a desired height adjustment design appropriate for the associated vehicle.
The spring seat 111 can have two cylindrical sections separated by the external flange, such that each of the cylindrical sections has a different length. The components of the spring seat 111 including the internal attachment mechanism, the external attachment mechanism, the cylindrical sections and similar components that can all be integrally formed or any combination of these features that can be integrally formed. The embodiment providing integral formation of the components provides an improved reliability in the adjustment of the spring height due to the reduction in the number of parts and the possible methods for the shock absorber 109 to be engaged by the spring seat 111.
The reversed orientation is demonstrated by the labels 111A and 111B in
The external attachment mechanism 203 can be a flange, ridge, collar or similar structure that is attached to or integral with the base cylinder of the spring seat 111. This external attachment mechanism 203 can define two opposing surfaces 207A, B. Each of these external attachment mechanism 203 surfaces 207A, B can engage a coil spring when the spring seat 111 is oriented with the respective surface 207A, 207B facing the coil spring. The opposing surfaces 207A, B of the external attachment mechanism 203 can be roughly orthogonal to the exterior cylinder surface. The diameter of the external attachment mechanism 203 and the surface areas of the surfaces 207A, B can vary dependent on the size of the coil spring to be received and the diameter of the shock absorber to which the spring seat is attached. In one embodiment, the external attachment mechanism extends outward from the exterior cylindrical surface 0.25 to four inches. The external attachment mechanism can have a thickness of 0.5 inches to one inch dependent on design of the vehicle suspension system.
The external attachment mechanism 203 can have any placement between the two edges 111A, B of the spring seat 111. The position of the external attachment mechanism 203 along the length of the cylinder of the spring seat 111 defines an upper cylinder portion 201 and a lower cylinder portion 205. The upper cylinder portion 201 and lower cylinder portion 205 are asymmetrical relative to the cross-plane of the external attachment mechanism 203 or the internal attachment mechanism. The upper cylinder portion 201 and lower cylinder portion 205 can have the same internal and external cylinder diameters.
The internal attachment mechanism 301 can be a lip, ridge, ring, collar or similar structure attached to or defined by the interior wall 307 of the spring seat 111. The internal attachment mechanism 301 can complement an attachment mechanism of the shock absorber to secure the spring seat 111 to the shock absorber independently or to secure the spring seat 111 to the shock absorber in combination with the coil spring. The internal attachment mechanism 301 can be positioned within the spring seat 111 at any point along the length of the interior cylinder or at either end of the spring seat 111. The internal attachment mechanism 301 can define opposing surfaces for engaging the shock absorber in each orientation. The internal attachment mechanism 301 can define a structure that extends inward orthogonal to the interior surface 307 of the spring seat. The internal attachment mechanism 301 can extend inward 0.1 to one inches and have any thickness (e.g., 0.5 inches to one inch) dependent on the complementary structure of the attachment mechanism of the shock absorber and required material strength.
The adjustment process can be initiated by disengaging the shock absorber from the vehicle suspension system at the upper and/or lower mount (Block 401). The process could be completed in some instances by disengaging only one end of the shock absorber dependent on the vehicle suspension system. In other embodiments, both ends of the shock absorber may need to be disengaged from the wheel spindle assembly and vehicle body, respectively. Also, the shock absorber is likely to be disengaged from the coil spring to provide access to the spring seat.
The spring seat can slide over the length of the shock absorber to disengage the spring seat from the shock absorber (Block 403). In some embodiments, the spring seat internal attachment mechanism may have a release or similar component that must be activated or separately disengaged to free the spring seat from the shock absorber. The freed spring seat can then be reversed such that the orientation of the cylinder of the spring seat is flipped relative to the orientation of the shock absorber (Block 405).
The reversed spring seat is then slid back over the length of the shock absorber to re-engage the spring seat with the shock absorber (Block 407). Due to the asymmetrical placement of either the interior attachment mechanism or external attachment mechanism of the spring seat (or both attachment mechanisms), the position of the external attachment mechanism is altered compared to the prior position when the spring seat was attached with the opposite orientation. The position of the internal attachment mechanism can alter the position at which the spring seat engages the shock absorber and as a result the position of the external attachment mechanism alters the spring height of the vehicle suspension system. The shock absorber can then be re-engaged with either the wheel spindle assembly and/or the vehicle body at the lower mount and upper mount, respectively (Block 409). The shock absorber and spring seat can also re-engage the coil spring adjacent the upper mount of the shock absorber.
It is to be understood that the above description is intended to be illustrative and not restrictive. Many other embodiments will be apparent to those of skill in the art upon reading and understanding the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.
