Valve assembly for a damper

#The present disclosure generally relates to dampers. More particularly, the present disclosure relates to a valve assembly for dampers.

#Shock absorbers/dampers are generally installed on different types of equipment, such as vehicles, to dampen vibrations during operation. For example, dampers are generally connected between a body and the suspension system of the vehicle in order to absorb the vibrations. There are different types of dampers, for example, mono-tube dampers and double-tube dampers. Conventional mono-tube dampers typically include a pressure tube, a piston and a piston rod. The mono-tube dampers further include a floating piston to compensate for the volume of the piston rod. During a compression stroke and a rebound stroke of the damper, the piston can limit a flow of damping fluid between working chambers defined within the pressure tube due to which the damper produces a damping force for counteracting the vibrations. Conventional double-tube dampers typically include a reserve tube disposed around the pressure tube, and one or more additional valves.

#Various types of damping force generating devices have been developed to generate desired damping forces in relation to the frequency of the inputs from the roads over which the vehicles travel. A frequency dependent selective damping device generally includes a spool valve movably disposed within a housing to provide the ability to have softer damping characteristics with higher frequency road inputs. These softer damping characteristics lead to a more effective isolation of a body of the vehicles from unwanted disturbances. Typically, these frequency dependent damping devices operate during an extension or rebound movement, a compression movement, or both rebound and compression movements of the hydraulic damper or shock absorber.

#FIG. 1 is an illustration of a vehicle incorporating a suspension system, according to an aspect of the present disclosure;

#FIG. 2 is a schematic illustration of a damper associated with the suspension system of FIG. 1, according to an aspect of the present disclosure;

#FIG. 3A, is schematic illustration of a piston assembly and a valve assembly of the damper shown in FIG. 2, according to an aspect of the present disclosure;

#Wherever possible, the same reference numbers will be used throughout the drawings to refer to same or like parts.

#Aspects of the disclosure generally relate to a valve assembly for a damper. The valve assembly includes a spool valve movably disposed within a housing. The valve assembly includes a bumper disposed between the housing and the spool valve. The spool valve, the bumper and the housing together define an enclosed volume. In some cases, the enclosed volume is not filled with hydraulic fluid and is therefore an air pocket. After pressurizing of the damper, the enclosed volume can have a low pressure. The spool valve can be blocked from movement within the housing due to the low pressure within the enclosed volume. At least one of the spool valve, the bumper and the housing is provided with one or more bleed paths to allow fluid exchange with the enclosed volume and ensure desired movement of the spool valve within the housing. The valve assembly can eliminate rejection of the damper due to the blocking of the spool valve.

#FIG. 1 illustrates an exemplary vehicle 100 in accordance with the present disclosure. The vehicle 100 can include a vehicle driven by an internal combustion engine, an electric vehicle, or a hybrid vehicle. The vehicle 100 includes a rear suspension 112, a front suspension 114 and a body 116. The rear suspension 112 has a transversely extending rear axle assembly (not shown) adapted to operatively support a pair of rear wheels 118. The rear axle is attached to the body 116 by a pair of dampers 120 and a pair of springs 122. Similarly, the front suspension 114 includes a transversely extending front axle assembly (not shown) to operatively support a pair of front wheels 124. The front axle assembly is attached to the body 116 by a pair of dampers 126 and a pair of springs 128. The dampers 120 and 126 serve to dampen the relative motion of the unsprung portion (i.e., the front and rear suspensions 114, 112) with respect to the sprung portion (i.e., the body 116) of the vehicle 100. While the vehicle 100 has been depicted as a passenger car having front and rear axle assemblies, the dampers 120 and 126 can be used with other types of vehicles or in other types of applications including, but not limited to, vehicles incorporating non-independent front and/or non-independent rear suspensions, vehicles incorporating independent front and/or independent rear suspensions or other suspension systems known in the art. Further, the term damper as used herein is meant to refer to dampers in general and thus will include McPherson struts and other damper designs known in the art.