# US 2021/0277974 A1 · Shock absorber and shock absorber assembly > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0277974 A1 - Document ID: US20210277974A1 - Status: Published application - Kind: A1 - Application number: 17/196,561 - Filed: 2021-03-09 - Published: 2021-09-09 - Earliest claimed: 2020-03-09 - Assignees: Ford Global Technologies, LLC - Applicants: Ford Global Technologies, LLC - Inventors: Marc Simon; Felix Fischer; Teiwen Fehse; Olivier Reinertz; Katharina Schmitz; Raif Hintzen; Achim Lordick - Web page: https://patentgrep.com/patent/US20210277974A1 ## CPC - F16F 9/469: {Valves incorporated in the piston (F16F9/467 takes precedence)} - B60G 17/018: characterised by the use of a specific signal treatment or control method - B60G 21/073: between wheels on the same axle but on different sides of the vehicle, i.e. the left and right wheel suspensions being interconnected - F16F 9/22: with one or more cylinders each having a single working space closed by a piston or plunger - F16F 9/3221: {of piston rods} - F16F 9/3257: {in twin-tube type devices} - F16F 9/435: {via opening in cylinder wall (F16F9/432 takes precedence)} - B60G 2400/252: vertical - B60G 2800/01: Attitude or posture control - F16F 9/062: {Bi-tubular units} - F16F 9/063: {comprising a hollow piston rod} - F16F 9/3235: {of cylinders (F16F9/483 takes precedence)} - F16F: SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION - B60G: VEHICLE SUSPENSION ARRANGEMENTS (air-cushion vehicles B60V; {cycle suspensions B62K25/00}) ## Abstract A shock absorber for a wheel suspension of a vehicle may include an outer cylinder, an outer piston that is axially displaceably guided in the outer cylinder, an inner piston that is axially displaceably guided in the outer piston, and a piston rod that is connected to the inner piston and that is guided out of the outer piston. A surface, which is located remote from the piston rod, of a piston portion of the outer piston, which is axially displaceably guided on an inner lateral surface of the outer cylinder, is connected so as to communicate partially with surroundings of the shock absorber. ## Claims ### Claim 1 A shock absorber for a wheel suspension of a vehicle, the shock absorber comprising: an outer cylinder; an outer piston that is axially displaceably guided in the outer cylinder; an inner piston that is axially displaceably guided in the outer piston; and a piston rod that is connected to the inner piston and that is guided out of the outer piston, wherein a surface, which is located remote from the piston rod, of a piston portion of the outer piston, which is axially displaceably guided on an inner lateral surface of the outer cylinder, is connected so as to communicate partially with surroundings of the shock absorber. ### Claim 2 (depends on 1) The shock absorber of claim 1, wherein the outer piston further includes a cylinder portion and a guide portion, wherein the cylinder portion is concentrically connected to the piston portion and is axially displaceably guided on a central guide opening on a front wall of the outer cylinder axially closing the outer cylinder on one side, and wherein the guide portion is arranged on a side of the piston portion opposing the cylinder portion and is concentrically connected to the piston portion, and wherein the guide portion has an annular configuration. ### Claim 3 (depends on 2) The shock absorber of claim 2, wherein the inner piston includes a piston portion and a guide pin, wherein the piston portion is axially displaceably guided on an inner lateral surface of the cylinder portion and is connected to the piston rod, wherein the guide pin is arranged on a side of the piston portion remote from the piston rod and is concentrically connected to the piston portion, wherein the guide pin is axially displaceably guided on an inner lateral surface of the guide portion, and wherein a fluid channel is provided with at least one piston valve to run axially through the piston portion of the inner piston and the guide pin. ### Claim 4 (depends on 1) The shock absorber of claim 1, wherein the inner piston includes a piston portion and a guide pin, wherein the piston portion is axially displaceably guided on an inner lateral surface of the cylinder portion and is connected to the piston rod, wherein the guide pin is arranged on a side of the piston portion remote from the piston rod and is concentrically connected to the piston portion, wherein the guide pin is axially displaceably guided on an inner lateral surface of the guide portion, and wherein a fluid channel is provided with at least one piston valve to run axially through the piston portion of the inner piston and the guide pin. ### Claim 5 (depends on 4) The shock absorber of claim 4, wherein an opening is configured on a lateral surface of the cylinder portion, wherein a first working chamber is located inside the cylinder portion and is arranged on a side of the piston portion of the inner piston remote from the piston rod is connected by the opening so as to communicate with a second working chamber that radially outwardly encloses the cylinder portion inside the outer cylinder and that is axially defined on one side by the piston portion of the outer piston, wherein an inner cylinder having an annular configuration is filled with a gas and is immovably fastened to the inner lateral surface of the outer cylinder over a circumference of the inner lateral surface, wherein the guide portion of the outer piston is axially displaceably guided on the inner lateral surface of the guide portion, and wherein the inner cylinder is closed on a side facing the piston portion of the outer piston via an annular terminal element and on a side remote from the piston portion of the outer piston via a separating piston that is axially displaceably guided inside the inner cylinder. ### Claim 6 (depends on 5) The shock absorber of claim 5, wherein an opening is configured on a portion of the outer cylinder that is arranged between the piston portion of the outer piston and the terminal element of the inner cylinder, wherein an internal space is disposed between the piston portion and the terminal element and connected to the surroundings of the shock absorber by the opening. ### Claim 7 (depends on 1) The shock absorber of claim 1, wherein an opening is configured on a portion of the outer cylinder that is arranged between the piston portion of the outer piston and a terminal element of an inner cylinder, wherein an internal space is disposed between the piston portion and the terminal element and connected to the surroundings of the shock absorber by the opening. ### Claim 8 A shock absorber assembly for a wheel suspension of a vehicle, the assembly comprising: a pressure application device; and shock absorber operably coupled to the pressure application device, the shock absorber comprising: an outer cylinder; an outer piston that is axially displaceably guided in the outer cylinder; an inner piston that is axially displaceably guided in the outer piston; and a piston rod that is connected to the inner piston and that is guided out of the outer piston, wherein a surface, which is located remote from the piston rod, of a piston portion of the outer piston, which is axially displaceably guided on an inner lateral surface of the outer cylinder, is connected so as to communicate partially with surroundings of the shock absorber. ### Claim 9 (depends on 8) The assembly of claim 8, wherein the outer piston further includes a cylinder portion and a guide portion, wherein the cylinder portion is concentrically connected to the piston portion and is axially displaceably guided on a central guide opening on a front wall of the outer cylinder axially closing the outer cylinder on one side, and wherein the guide portion is arranged on a side of the piston portion opposing the cylinder portion and is concentrically connected to the piston portion, and wherein the guide portion has an annular configuration. ### Claim 10 (depends on 9) The assembly of claim 9, wherein the inner piston includes a piston portion and a guide pin, wherein the piston portion is axially displaceably guided on an inner lateral surface of the cylinder portion and is connected to the piston rod, wherein the guide pin is arranged on a side of the piston portion remote from the piston rod and is concentrically connected to the piston portion, wherein the guide pin is axially displaceably guided on an inner lateral surface of the guide portion, and wherein a fluid channel is provided with at least one piston valve to run axially through the piston portion of the inner piston and the guide pin. ### Claim 11 (depends on 8) The assembly of claim 8, wherein the inner piston includes a piston portion and a guide pin, wherein the piston portion is axially displaceably guided on an inner lateral surface of the cylinder portion and is connected to the piston rod, wherein the guide pin is arranged on a side of the piston portion remote from the piston rod and is concentrically connected to the piston portion, wherein the guide pin is axially displaceably guided on an inner lateral surface of the guide portion, and wherein a fluid channel is provided with at least one piston valve to run axially through the piston portion of the inner piston and the guide pin. ### Claim 12 (depends on 11) The assembly of claim 11, wherein an opening is configured on a lateral surface of the cylinder portion, wherein a first working chamber is located inside the cylinder portion and is arranged on a side of the piston portion of the inner piston remote from the piston rod is connected by the opening so as to communicate with a second working chamber that radially outwardly encloses the cylinder portion inside the outer cylinder and that is axially defined on one side by the piston portion of the outer piston, wherein an inner cylinder having an annular configuration is filled with a gas and is immovably fastened to the inner lateral surface of the outer cylinder over a circumference of the inner lateral surface, wherein the guide portion of the outer piston is axially displaceably guided on the inner lateral surface of the guide portion, and wherein the inner cylinder is closed on a side facing the piston portion of the outer piston via an annular terminal element and on a side remote from the piston portion of the outer piston via a separating piston that is axially displaceably guided inside the inner cylinder. ### Claim 13 (depends on 12) The assembly of claim 12, wherein an opening is configured on a portion of the outer cylinder that is arranged between the piston portion of the outer piston and the terminal element of the inner cylinder, wherein an internal space is disposed between the piston portion and the terminal element and connected to the surroundings of the shock absorber by the opening. ### Claim 14 (depends on 8) The assembly of claim 8, wherein an opening is configured on a portion of the outer cylinder that is arranged between the piston portion of the outer piston and a terminal element of an inner cylinder, wherein an internal space is disposed between the piston portion and the terminal element and connected to the surroundings of the shock absorber by the opening. ### Claim 15 (depends on 14) The assembly of claim 14, wherein the pressure application device is operably coupled to the opening on the portion of the outer cylinder to apply gas to the internal space.