Abstract: A shock absorber piston has an upper half, a lower half and a tuning disc disposed between the upper and lower halves. The design for the openings in the tuning disc can be selected to individually tune the high and low speed damping characteristics in both compression and extension movements of the shock absorber.

Abstract: A measuring tool is designed to measure the relationship between an inner hub land and an outer land for a valve body. A locating face engages the inner hub land such that the measurements are taken with respect to the inner hub land. A probe is designed to engage the outer land. By rotating the valve body, the entire circumference of the outer land can be measured in relation to the inner hub land.

Abstract: A shock absorber includes a rebound valve assembly which performs the flexing disc function normally required for allowing the passage of fluid from one side of a piston assembly to the opposite side during the stroke of the shock absorber. The rebound valve assembly also incorporates a blow off function which increases the fluid flow through the piston when the fluid pressure being exerted upon the rebound valve assembly exceeds a specified level. The blow off feature utilizes a coil spring to protect both the shock absorber as well as the suspension system into which the shock absorber is assembled.

Abstract: A shock absorber piston assembly includes a piston having a first face, a second face and a plurality of fluid passages. Preloaded flow control devices each seal at least one of the fluid passages, including: a first bleed plate contacting the first face and a second bleed plate contacting the second face; and a pair of blow-off discs, with a first blow-off disc contacting the first face and a second blow-off disc contacting the second face. Each of the flow control devices opens at an individually adjustable device opening pressure. Each of the multiple passages in contact with the blow-off discs can also differ in flow area to permit the blow-off discs to angularly lift to limit disc chatter.

Abstract: A shock absorber has a pressure tube with a piston assembly slidably disposed within the pressure tube and attached to a piston rod. The piston assembly divides the pressure tube into an upper working chamber and a lower working chamber. The piston assembly includes a compression and a rebound valve assembly. The piston assembly also includes a housing attached to the piston rod which defines a pressure chamber within which is slidably disposed a piston to define upper and lower fluid chambers. The pressure chamber is in communication with the upper working chamber through a passageway extending through the piston rod. The housing, piston and fluid chambers provide two stage damping in rebound and compression with a smooth transition between soft and firm damping.

Abstract: A valve for controlling fluid flow through a passage defined by a valve body or a piston includes a valve disc which abuts the valve body or the piston. The valve body or the piston defines a first land for supporting the valve disc, a second land for supporting the valve disc located radially inward from the first land and a support surface for the valve disc located between the first and second lands. This valve disc abuts the first and second lands and a clearance is defined between the valve disc and the support surface.

Abstract: A dual tube shock absorber has a base valve assembly which includes both low speed control using a bleed type orifice and high speed/high pressure blow off control using a disc spring. The base valve assembly provides this variable damping force characteristic while reducing the dead length of the shock absorber.

Abstract: A valve for controlling fluid flow through a passage defined by a valve body or a piston includes a valve disc which abuts the valve body or the piston. The valve body or the piston defines a first land for supporting the valve disc, a second land for supporting the valve disc located radially inward from the first land and a support surface for the valve disc located between the first and second lands. This valve disc abuts the first and second lands and a clearance is defined between the valve disc and the support surface.

Abstract: A dual tube shock absorber has a base valve assembly which includes both low speed control using a bleed type orifice and high speed/high pressure blow off control using a disc spring. The base valve assembly provides this variable damping force characteristic while reducing the dead length of the shock absorber.

Abstract: A shock absorber has a pressure tube with a piston assembly slidably disposed within the pressure tube and attached to a piston rod. The piston assembly divides the pressure tube into an upper working chamber and a lower working chamber. The piston assembly includes a compression and a rebound valve assembly. The piston assembly also includes a housing attached to the piston rod which defines a pressure chamber within which is slidably disposed a piston to define upper and lower fluid chambers. The pressure chamber is in communication with the upper working chamber through a passageway extending through the piston rod. The housing, piston and fluid chambers provide two stage damping in rebound and compression with a smooth transition between soft and firm damping.

Abstract: A shock absorber piston assembly includes a piston having a first face, a second face and a plurality of fluid passages. Preloaded flow control devices each seal at least one of the fluid passages, including: a first bleed plate contacting the first face and a second bleed plate contacting the second face; and a pair of blow-off discs, with a first blow-off disc contacting the first face and a second blow-off disc contacting the second face. Each of the flow control devices opens at an individually adjustable device opening pressure. Each of the multiple passages in contact with the blow-off discs can also differ in flow area to permit the blow-off discs to angularly lift to limit disc chatter.

Abstract: A shock absorber includes a rebound valve assembly which performs the flexing disc function normally required for allowing the passage of fluid from one side of a piston assembly to the opposite side during the stroke of the shock absorber. The rebound valve assembly also incorporates a blow off function which increases the fluid flow through the piston when the fluid pressure being exerted upon the rebound valve assembly exceeds a specified level. The blow off feature utilizes a coil spring to protect both the shock absorber as well as the suspension system into which the shock absorber is assembled.

Abstract: A shock absorber includes a rebound valve assembly which performs the flexing disc function normally required for allowing the passage of fluid from one side of a piston assembly to the opposite side during the stroke of the shock absorber. The rebound valve assembly also incorporates a blow off function which increases the fluid flow through the piston when the fluid pressure being exerted upon the rebound valve assembly exceeds a specified level. The blow off feature protects both the shock absorber as well as the suspension system into which the shock absorber is assembled.

Abstract: A passive damping for a shock absorber is disclosed. The shock absorber includes a working chamber, and a piston disposed in the working chamber. The piston includes a primary bypass valve for defining an upper fluid portion and a lower fluid portion. A piston rod is connected to the piston and extends through the top portion of the working chamber. A variable bypass assembly is disposed between a first fluid chamber and a second fluid chamber. The variable bypass assembly includes at least one bypass aperture for providing communication of damping fluid between the first and second fluid chambers. The variable bypass assembly also includes a passive control member for varying the size of the bypass aperture, and biasing structure for normally retaining the passive control member in a position which maximizes the size of the bypass aperture.

Abstract: A shock absorber has a pressure tube with a piston assembly slidably disposed within the pressure tube and attached to a piston rod. The piston assembly divides the pressure tube into an upper working chamber and a lower working chamber. The piston assembly includes a compression and a rebound valve assembly. The piston assembly also includes a housing attached to the piston rod within which is slidably disposed a piston to define a closed chamber. The closed chamber is in communication with one of the working chambers through a passageway extending through the piston rod. The housing and piston provide two stage damping in rebound and compression with a smooth transition between soft and firm damping.

Abstract: A passive damping system for a shock absorber is disclosed. The shock absorber includes a working chamber, and a piston disposed in the working chamber. The piston includes a primary bypass valve for defining an upper fluid portion and a lower fluid portion. A piston rod is connected to the piston and extends through the top portion of the working chamber. A variable bypass assembly is disposed between a first fluid chamber and a second fluid chamber. The variable bypass assembly includes at least one bypass aperture for providing communication of damping fluid between the first and second fluid chambers. The variable bypass assembly also includes a passive control member for varying the size of the bypass aperture, and biasing structure for normally retaining the passive control member in a position which maximizes the size of the bypass aperture.

Abstract: A shock absorber utilizes a single flexing disc assembly includes a flexing disc which is capable of performing the flexing disc function normally required for allowing the passage of fluid between the two sides of a shock absorber while also providing the blow off function. The flexing disc is backed by a ridge formed on a spring seat. The ridge defines a ring that is concentric with the central long axis of the piston rod. Under normal rebounding conditions, the pressure of rebounding damping fluid builds to the point that the flexing disc is opened somewhat by flexing to allow normal bleedthrough. However, in the event that the rebound pressure builds to a higher, predetermined value, the valve flexes to an extreme degree against the ridge formed on the spring seat. In this manner, the ring acts as a fulcrum, and a quantity of damping fluid is allowed to pass thereby until normal rebound pressure values are reached.

Abstract: An anti-swish mechanism for a damper is disclosed to reduce the swish noise heard during movement of a piston assembly within the damper. The damper includes a pressure cylinder which forms a working chamber having a first portion and a second portion operable to store damping fluid. A piston rod is partially disposed within a pressure cylinder and a piston body is secured within the piston rod. Extending from the piston body are first and second annular axially extending lands which are concentric with the piston body. A set of axially extending, circumferentially spaced flow ports are formed in the piston body between the first and second annular axially extending lands. Adjacent to the flow ports is an anti-swish mechanism which reduces "swish" noise as the piston body moves within the pressure cylinder.

Abstract: An anti-swish mechanism for a damper is disclosed to reduce the swish noise heard during movement of a piston assembly within the damper. The damper includes a pressure cylinder which forms a working chamber having a first portion and a second portion operable to store damping fluid. A piston rod is partially disposed within a pressure cylinder and a piston body is secured within the piston rod. Extending from the piston body are first and second annular axially extending lands which are concentric with the piston body. A set of axially extending, circumferentially spaced flow ports are formed in the piston body between the first and second annular axially extending lands. Adjacent to the flow ports is an anti-swish mechanism which reduces "swish" noise as the piston body moves within the pressure cylinder.

Abstract: A shock absorber utilizes an array of restrictive rebound fluid flow passages radially formed in a piston assembly. The flow passages are defined by a relatively narrow entrance and a relatively wide exit. A contoured wall form one wall of the passage. The restrictive rebound fluid flow passages restrict the flow-through of rebound fluid. The damping characteristics of the shock absorber are determined by the restriction caused by the general shape of the passages. Because restriction produced by the passages is a function of the contour of the passages and the entrance and exit widths, virtually any damping curve may be achieved by forming a passage having a selected contour.