# US 9,518,627 B2 · Changes enabling the elimination of processes for a torsion bar > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,518,627 B2 - Document ID: US9518627B2 - Status: Granted - Kind: B2 - Application number: 14/554,600 - Filed: 2014-11-26 - Published: 2016-05-26 - Granted: 2016-12-13 - Earliest claimed: 2014-11-26 - Assignees: Steering Solutions IP Holding Corporation - Applicants: Steering Solutions IP Holding Corporation - Inventors: Eric D. Pattok; Alan J. Armitage - Web page: https://patentgrep.com/patent/US9518627B2 ## CPC - B62D 1/16: Steering columns - B21B 15/0007: {Cutting or shearing the product} - B62D 5/083: Rotary valves - B62D 6/10: characterised by means for sensing {or determining} torque - C21D 1/18: Hardening (C21D1/02 takes precedence); Quenching with or without subsequent tempering (quenching devices C21D1/62) - C21D 9/0068: {for particular articles not mentioned below} - F16D 1/10: Quick-acting couplings in which the parts are connected by simply bringing them together axially - F16F 1/14: Torsion springs consisting of bars or tubes - F16D 2001/103: {the torque is transmitted via splined connections} - B62D: MOTOR VEHICLES; TRAILERS (steering, or guiding on a desired track, of agricultural machines or implements A01B69/00; wheels, castors, axles, increasing wheel adhesion B60B; vehicle tyres, tyre inflation or tyre changing B60C; connections between vehicles of a train or the like B60D; vehicles for use on rail and road, amphibious or convertible vehicles B60F; suspension arrangements B60G; heating, cooling, ventilating or other air treating devices B60H; windows, windscreens, non-fixed roofs, doors or similar devices, protective coverings for vehicles not in use B60J; propulsion plant arrangements, auxiliary drives, transmissions, controls, instrumentation or dashboards B60K; electric equipment or propulsion of electrically-propelled vehicles B60L; power supply for electrically-propelled vehicles B60M; passenger accommodation not otherwise provided for B60N; adaptations for load transportation or to carry special loads or objects B60P; arrangement of signalling or lighting devices, the mounting or supporting thereof or circuits therefor, for vehicles in general B60Q; vehicles, vehicle fittings or vehicle parts not otherwise provided for B60R; servicing, cleaning, repairing, supporting, lifting, or manoeuvring, not otherwise provided for, B60S; brake arrangements, brake control systems or parts thereof B60T; air-cushion vehicles B60V; motor-cycles, accessories therefor B62J, B62K; testing of vehicles G01M) - B21B: ROLLING OF METAL (auxiliary operations used in connection with metal-working operations covered in B21, see B21C; bending by rolling B21D; manufacture of particular objects, e.g. screws, wheels, rings, barrels, balls, by rolling B21H; pressure welding by means of a rolling mill B23K20/04) - C21D: MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING (surface treatment of metallic material involving at least one process provided for in class C23 and at least one process covered by this subclass C23F17/00; unidirectional solidification of eutectic materials or unidirectional demixing of eutectoid materials C30B) - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES - F16F: SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION ## Abstract In one aspect of the invention, a torsion bar assembly is provided. The assembly includes a first shaft having a first bore, a second shaft having a second bore, the second shaft operatively coupled to the first shaft, and a torsion bar positioned within the first and second bores. The torsion bar includes a splined first end having a first diameter extending to a first end face having a diameter generally the same as the first diameter, a splined second end having a second diameter extending to a second end face having a diameter generally the same as the second diameter, and an active diameter extending between the splined first end and the splined second end. The torsion bar is fabricated from a material having a hardness greater than 45 Rockwell C-Scale. ## Claims ### Claim 1 A torsion bar assembly for a steering column assembly, the torsion bar assembly comprising: a first steering column shaft having a first bore; a second steering column shaft having a second bore, the second shaft operatively coupled to the first shaft; and a torsion bar positioned within the first and second bores, the torsion bar, the first and second bores coaxially aligned along their respective longitudinal axes, the torsion bar comprising: a splined first end having a first diameter extending completely to a first end face having a diameter generally the same as the first diameter; a splined second end having a second diameter extending completely to a second end face having a diameter generally the same as the second diameter; an active diameter extending between the splined first end and the splined second end; and a minor diameter of the splined first end smaller than the active diameter. ### Claim 2 (depends on 1) The torsion bar assembly of claim 1, wherein at least one of the first and second diameters is equal to the active diameter. ### Claim 3 (depends on 2) The torsion bar assembly of claim 2, wherein the at least one of the splined first and second ends does not include a blend between the large diameter and the active diameter. ### Claim 4 (depends on 1) The torsion bar assembly of claim 1, wherein at least one of the splined first and second ends does not include a bullet nose. ### Claim 5 (depends on 1) The torsion bar assembly of claim 1, wherein the torsion bar has a length between 90 mm and 110 mm. ### Claim 6 (depends on 1) The torsion bar assembly of claim 1, wherein the torsion bar is fabricated from a material having a hardness of between 48 and 55 Rockwell C-Scale. ### Claim 7 (depends on 1) The torsion bar assembly of claim 1, wherein the first bore does not include a reamer bore.