US 5,706,919 AGranted

Alternating state pressure regulation valved damper

AssigneeGeneral Motors Corporation

InventorsWilliam Charles Kruckemeyer, Richard Edward Longhouse, Patrick Neil Hopkins, Michael Leslie Oliver, Michael Anthony Dimatteo

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Abstract

A damper includes a piston that carries a relatively compact control valve for controlling fluid flow through the piston. The control valve provides a variable amount of damping by regulating damper fluid flow between the extension chamber and the compression chamber of the damper during extension and compression strokes. Pressure regulation across the piston is controlled through two alternate flow paths as determined by the control valve. Damping through the first flow path is relatively soft and is determined according to the deflective characteristics of a single bi-directional annular disc valve. Damping through the second flow path is relatively firm and is determined by the first bi-directional single annular disc and a second bi-directional single annular disc in series.

Claims11

Dependent claims

A suspension damper comprising:

a single cylinder defining a substantially liquid filled cavity;
a piston slidably positioned in the single cylinder separating the cavity into a compression chamber and an extension chamber;
a rod attached to the piston and extending through the extension chamber and exiting the cavity;
wherein the piston is slidable in a compression direction such that an increasing volume of the rod enters the cavity and in an extension direction such that an increasing volume of the rod exits the cavity wherein a passage is provided through the piston so that a liquid exchange is effected between the extension chamber and the compression chamber during sliding of the piston in the extension and compression directions;
wherein the passage has a first branch and a second branch, the liquid exchange being selectively effected through the first branch that includes a bi-directional deflectable first single annular disc tuned to effect a relatively soft damping rate, the first single annular disc controlling damping forces at all flow rates in both directions during extension direction and compression direction travel of the piston and the first branch also including a remotely operated control valve being selectively positioned in a first open position substantially freely allowing liquid exchange through the first branch and a second closed position substantially preventing liquid exchange through the first branch, and the liquid exchange being selectively effected through the second branch that includes the bi-directional deflectable first single annular disc tuned to effect a soft damping rate and a bi-directional deflectable second single annular disc tuned to effect a firm damping rate wherein when the remotely operated control valve is in the first open position the monotube suspension damper develops a first damping rate wherein force is dependent upon velocity of the sliding piston and the first damping rate is substantially determined by deflective characteristics solely of the first single annular disc and when the remotely operated control valve is in the second closed position the monotube suspension damper develops a second damping rate wherein force is dependent upon velocity of the sliding piston and the second damping rate is substantially determined by deflective characteristics of the first single annular disc and the second single annular disc in series.

2 more elements

A suspension damper comprising:

a cylinder defining a substantially liquid filled cavity;
a piston slidably positioned in the cylinder separating the cavity into a compression chamber and an extension chamber;
a rod attached to the piston and extending through the extension chamber and exiting the cavity;
wherein the piston includes a remotely operated control valve having a solenoid housing and a cylindrical body;
a first indexing spacer having a first leg and positioned over the cylindrical body near the solenoid housing;
a first support disc having a notch receiving the first leg and positioned over the cylindrical body against the first indexing spacer;
a first centering disc having a notch receiving the first leg and positioned over the cylindrical body against the first support disc;
a bi-directional, deflectable first single annular disc positioned around the first centering disc, the first single annular disc having an outer periphery;
a valve plate positioned on the cylindrical body against the first centering disc and supporting the outer periphery of the first single annular disc;
a second indexing spacer having a second leg and positioned over the cylindrical body near the valve plate;
a second support disc having a notch receiving the second leg and positioned over the cylindrical body against the second indexing spacer;
a second centering disc having a notch receiving the second leg and positioned over the cylindrical body against the second support disc;
a bi-directional, deflectable second single annular disc positioned around the second centering disc, the second single annular disc having an outer periphery;
a piston cup fixed on the cylindrical body near the second centering disc and supporting the outer periphery of the second single annular disc;
wherein the piston is slidable in a compression direction such that an increasing volume of the rod enters the cavity and in an extension direction such that an increasing volume of the rod exits the cavity wherein a passage is provided through the piston so that a liquid exchange is effected between the extension chamber and the compression chamber during sliding of the piston in the extension and compression directions;
wherein the passage has a first branch and a second branch, the liquid exchange being selectively effected through the first branch that includes the first single annular disc tuned to effect a relatively soft damping rate the first single annular disc controlling damping forces at all flow rates in both directions during extension direction and compression direction travel of the piston and the first branch also including the control valve, the control valve being selectively positioned in a first open position substantially freely allowing liquid exchange through the first branch and in a second closed position substantially preventing liquid exchange through the first branch, and the liquid exchange being selectively effected through the second branch that includes the first single annular disc tuned to effect a soft damping rate and the second single annular disc tuned to effect a firm damping rate wherein when the remotely operated control valve is in the first open position the monotube suspension damper develops a first damping rate wherein force is dependent upon velocity of the sliding piston and the first damping rate is substantially determined by deflective characteristics solely of the first single annular disc and when the remotely operated control valve is in the second closed position the monotube suspension damper develops a second damping rate wherein force is dependent upon velocity of the sliding piston and the second damping rate is substantially determined by deflective characteristics of the first single annular disc and the second single annular disc in series.

13 more elements

Dependencies are inferred from the claim text.