(19) TZZ Z__T (11) EP 2 657 081 A1 (12) EUROPEAN PATENT APPLICATION (43) Date of publication: (51) Int Cl.: 30.10.2013 Bulletin 2013/44 B60Q 1/46 (2006.01) (21) Application number: 13173293.5 (22) Date of filing: 04.05.2009 (84) Designated Contracting States: (72) Inventor: Juriga, James Andrew AT BE BG CH CY CZ DE DK EE ES FI FR GB GR MI 48025 Beverly Hills (US) HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK TR (74) Representative: Delorme, Nicolas et al Cabinet Germain & Maureau (30) Priority: 02.05.2008 US 126426 BP 6153 69466 Lyon Cedex 06 (FR) (62) Document number(s) of the earlier application(s) in accordance with Art. 76 EPC: Remarks: 09746918.3 / 2 282 911 This application was filed on 21-06-2013 as a divisional application to the application mentioned (71) Applicant: Rassini S.A. de C.V. under INID code 62. Lomas de Chapultepec 11000 (MX) (54) Dual leaf vehicle suspension with J-shaped spring element (57) A vehicle suspension arrangement for a vehicle coupling to the chassis of the vehicle at a second pivot of the type having a chassis rail and a longitudinal axle coupling, and an axle coupler portion is arranged inter- arranged substantially orthogonal to the chassis rail has mediate of the first and second ends. A secondary leaf a primary spring with a predetermined resilience charac- spring has a first end for pivotally coupling to the chassis teristic, a first portion for coupling to the chassis of the of the vehicle at a pivot coupling, and a second end for vehicle at a primary coupling, and a second portion for coupling to the axle. A deflection limiting element is cou- coupling to the longitudinal axle. A primary leaf spring pled to a selectable one of the primary and secondary has a first end for pivotally coupling to the chassis of the leaf springs for controlling a distance therebetween. The vehicle at a first pivot coupling, and a second end for deflection limiting element is configured as a J-shaped spring element. EP 2 657 081 A1 Printed by Jouve, 75001 PARIS (FR) 1 EP 2 657 081 A1 2 Description mentemploys asolid axle, and therefore does not provide the benefits of independent suspension. In addition, this Relationship to Other Application known arrangement is plagued with the disadvantage of high unsprung mass. [0001] This application claims the benefit of the filing 5 [0006] A de Dion tube vehicle suspension arrange- date of Provisional Patent Application Serial Number ment is a known form of semi-independent suspension 61/126,426 filed May 2, 2008. The disclosure of this pro- andconstitutes an improvementover the Hotchkissdrive. visional patent application is incorporated herein by ref- In this type of suspension, universal joints are employed erence. at the wheel hubs and the differential, and there is addi- 10 tionally provided a solid tubular beam that maintains the Background of the Invention opposing wheels in parallel. The de Dion tube is not di- rectly connected to the chassis and is not intended to flex. FIELD OF THE INVENTION [0007] The benefits of a de Dion suspension include a reduction in the unsprung weight compared to the Hotch- [0002] This invention relates generally to suspension 15 kiss drive. This is achieved by coupling the differential to systems for vehicles, and more particularly, to a leaf sus- the chassis. In addition, there are no camber changes pension arrangement that employs a dual leaf suspen- during suspension unloading. Since the camber of both sion with a main spring deformation reduction element wheels is set at zero degrees, the traction from wide tires disposed therebetween on a substantially "J" or "L" is improved, and wheel hop under high power operations shaped spring support element. 20 is reduced compared to an independent suspension. However, the de Dion tube adds unsprung weight. DESCRIPTION OF THE RELATED ART [0008] It is, therefore, an object of this invention to pro- vide a vehicle suspension arrangement that provides the [0003] Leaf spring systems have for many years been benefits of independent suspension while using leaf used for the suspension of wheeled vehicles. The central 25 spring technology. element of a leaf spring suspension system for a vehicle [0009] It is another object of this invention to provide is termed a "semi-elliptical" spring configured as an arc- a vehicle suspension arrangement that employs leaf shaped length of spring steel having a substantially rec- spring technology and yet affords reduced unsprung tangular cross-section. At the center of the arc is provided mass for reduced inertial effects and improved vehicle an arrangement for coupling to the axle of the vehicle. 30 handling response. At the ends are provided coupler holes for attaching the [0010] It is also an object of this invention to provide a spring to the vehicle body. For heavy vehicles, leaf vehicle suspensionarrangement that employs leaf spring springs are stacked on one other to form layers of springs technology and affords reduced suspension inertia. of different lengths. Leaf springs are still used in heavy [0011] It is a further object of this invention to provide commercial vehicles and railway carriages. In the case 35 a vehicle suspension arrangement that employs leaf of very heavy vehicles, leaf springs provide the advan- spring technology and affords reduced noise, vibration, tage of spreading the load over a larger region of the and harshness (NVH). vehicle’s chassis. A coil spring, on the other hand, will [0012] It is additionally an object of this invention to transfer the load to a single point. provide a vehicle suspension arrangement that employs [0004] The well-known Hotchkiss drive, the name of 40 leaf spring technology and affords reduced lateral wheel which derives from the French automobile firm of Hotch- shake. kiss, employs a solid axle that is coupled at its ends to [0013] It is yet a further object of this invention to pro- the centers of respective semi-elliptical leaf springs. vide a vehicle suspension arrangement that employs leaf There are a number of problems with this form of drive spring technology and affords reduced side view wind- arrangement. First, this drive system is characterized by 45 up at the axle bracket. high unsprung mass. Additionally, the use of a solid axle [0014] It is also another object of this invention to pro- results in coupled left/right wheel motion. During heavy vide a vehicle suspension arrangement that employs leaf cornering and fast acceleration, this known system suf- spring technology and affords reduced forward and rear- fers from vertical deflection and wind-up. ward movement. [0005] One prior art effort to address the problems as- 50 [0015] It is yet an additional object of this invention to sociated with the Hotchkiss system employs a parallel provide a vehicle suspension arrangement that employs leaf spring arrangement at each end of a solid axle. This leaf spring technology and affords a semi-independent known arrangement affords increased axle control, in the suspension effect during asymmetric wheel travel. form of reduced power hop. Other advantages of this [0016] It is yet an additional object of this invention to known arrangement include roll under steer, auto load 55 provide a vehicle suspension arrangement that employs leveling and the gross vehicle weight, and no frame leaf spring technology in combination with a coil spring changes are required to convert from a Hotchkiss sys- element. tem. However, the known parallel leaf spring arrange- 2 3 EP 2 657 081 A1 4 Summary of the Invention [0021] In accordance with a further apparatus aspect of the invention, there is provided a vehicle suspension [0017] The foregoing and other objects are achieved arrangement for a vehicle of the type having a chassis by this invention which provides a vehicle suspension rail and a longitudinal axle arranged substantially orthog- arrangement for a vehicle of the type having a chassis 5 onal to the chassis rail. A principal resilient element has rail and a longitudinal axle arranged substantially orthog- a determinable resilience characteristic, the principal re- onal to the chassis rail, the vehicle suspension arrange- silient element having a first portion for coupling to the ment. In accordance with a first apparatus aspect of the chassis of the vehicle and a second portion for coupling invention, there is provided a primary leaf spring that has to the longitudinal axle. A secondary leaf spring is pro- a plan view longitudinal configuration, a first end for piv- 10 vided having a plan view longitudinal configuration, a first otally coupling to the chassis of the vehicle at a first pivot end for pivotally coupling to the chassis of the vehicle at coupling, and a second end for coupling to the chassis a secondary pivot coupling, and a second end for cou- of the vehicle at a second pivot coupling, and an axle pling to the longitudinal axle. Additionally, there is pro- coupler portion arranged intermediate of the first and sec- vided a deflection limiting element coupled to the sec- ond ends. Additionally, there is provided a secondary leaf 15 ondary leaf spring for limiting the extent of a leaf spring spring having a plan view longitudinal configuration, a deflection. first end for pivotally coupling to the chassis of the vehicle [0022] In an embodiment of the invention where the at a pivot coupling, and a second end for coupling to the principal resilient element is an air- pressure-assisted pri- longitudinal axle. There is advantageously provided a de- mary spring, such an air spring has a resilience charac- flection limiting element coupled to a selectable one of 20 teristic that is responsive to air pressure, a first portion the primary and secondary leaf springs for controlling a for coupling to the chassis of the vehicle at a primary distance therebetween.