~™ ii 1 1 mi ii ii 1 1 imii i in ii ii i ii (19) J European Patent Office

Office europeen des brevets (11) EP 0 937 634 A1

(12) EUROPEAN PATENT APPLICATION

(43) Date of publication:ation: (51) Int. CI.6: B62D 55/108, B60G 11/18 25.08.1999 Bulletin 1999/34

(21) Application number: 98103066.1

(22) Date of filing: 21 .02.1 998

(84) Designated Contracting States: (72) Inventor: Rantala, Klaus AT BE CH DE DK ES Fl FR GB GR IE IT LI LU MC 23500 Uusikaupunki (Fl) NL PT SE Designated Extension States: (74) Representative: AL LT LV MK RO SI Kaminski, Susanne, Dr. Patentburo Buchel & Partner AG (71) Applicant: Letzanaweg 25-27 VXO Group International AG 9495 Triesen (LI) 9490 Vaduz (LI)

(54) Tracke vehicle with torsion bar suspension

(57) In a vehicle with a hull (2) to which on the right sprung (5, 6) firmly anti -torsional anchored to a and left a track (4) is provided each running over at least swing arm (16, 16') runs staggered to the swinging axis three (5, 6), the wheels (5, 6) are pivoted on of this swing arm (16,16'). Consequently, the wheels (5, wheel suspensions with swing arms (16, 16'). To 6) can be arranged symmetrically with respect to the the movement of the swing arms (1 6, 1 6') around their vehicle medium plane running in the longitudinal direc- swinging axis, torsion bars (17, 20) are provided, tion. whereby at least one torsion bar section (20) of each

2 "VY19 (19a)

Fig. 3

CO CO co o Q_ LU Printed by Xerox (UK) Business Services 2.16.7/3.6 1 EP 0 937 634 A1 2

Description makes provision for the spring characteristic to be achieved via the interaction of at least two torsion bar [0001 ] The invention refers to a vehicle pursuant to the sections. Each swing arm is provided with at least two preamble of claim 1 . torsion bar sections pivoted with one another, whereby [0002] At least part of the weight of vehicles for difficult s a first torsion bar section - connected firmly to the swing terrain is transferred on to its tracks. Each track is arm - stretches along the swinging axis of the swing arm guided around road wheels and at least one idler wheel to a vertical medium plane of the hull and is pivotally as well as at least one sprocket drive. To enable the connected, especially in a positive-locking way, to a first area of the tracks in contact with the ground to adjust to end area of a second torsion bar section in front of the irregularities of the ground, the road wheels and the 10 medium plane. Said second section should preferably idler wheel are sprung. In the case of many known run parallel to the first and its second end area be firmly armoured, off-road and amphibian vehicles, torsion anti-torsional anchored to the hull. bars are applied for springing of the wheels. One end of [0007] The torsion bar sections adjacent to one these bars is anchored to the hull, the other end is another are connected to each other via a spur-gear attached to a swing arm pivoting around the axis of the 15 system. The gear systems are preferably each installed torsion bar. Each of the wheels to be sprung is pivotally in a gear case, said gear case being anchored particu- mounted in the area of the free end of a swing arm. The larly on both sides to a vertical dividing wall in the area length of the swing arm, the torsion capacity of the tor- of the medium plane of the hull. A preferred form of con- sion bars and their length are so dimensioned that the struction makes provision for a bearing box to be wheels are provided with the required vertical mobility 20 mounted at the swing arm on the outer wall of the hull. and springing characteristic. It is known that the The first torsion bar section is connected to said bearing required springing characteristic can only be achieved if box in a pivot bearing and the second end of the second the torsion bars extend across the entire width of the torsion bar section firmly anti-torsional anchored vehicle or hull. In order to spring the swing arms, so- thereto. As a result of using said gear case or bearing called staggered running gear is used. Thereby, at least 25 box and its location on the dividing wall or outer wall, the three wheels are provided on each side. Each wheel is springing of the various wheels are independent of each allotted a torsion bar, which essentially stretches across other, enabling assembly or removal of torsion bar sec- the free space between the wheels on the left and the tions of a wheel or swing arm to be carried out inde- right side of the vehicle. In the case of staggered run- pendently of the springing of the other wheels. ning gear, the rotary axis of the swing arms of the 30 [0008] It stands to reason that in the case of three or wheels opposite each other are somewhat offset in the more torsion bar sections also the torsion bar sections longitudinal direction of the vehicle. Accordingly, the on the outer wall are pivoted, especially in a positive- wheels too are not symmetrically arranged with respect locking way, with one another and if need be the last to a vehicle medium plane in longitudinal direction, but section is firmly anti-torsional anchored to the dividing are staggered. In addition to this asymmetry, there is the 35 wall. disadvantage that staggered torsion bars are difficult to [0009] The symmetrical arrangement of the swing assemble and replace. arms on both sides departs from staggered running [0003] Staggered running gear is used both for gear to a spring unit system, the torsion bars of a swing armoured vehicles having only tracks - such as the Ger- arm being independent of the suspension of the swing man Leopard - as well as for traction vehicles 40 arm located opposite. In addition to facilitating assembly which in addition to the tracks also include a pair of and repairing a broken torsion bar section, this unit sys- steerable - above all drivable - wheels, as used in the tem also has the advantage that stability is increased in DEMAG D7 (1938 to 1944). the area of the unit. In the event of distortion to the hull, [0004] The task of the invention is to find a suspension the torsion bar sections are less stressed than torsion solution which is easy to assemble and enabling sym- 45 bars in staggered running gear. metric arrangement of the wheels. [001 0] The drawings exemplify the invention based on [0005] This task is solved with the features of claim 1 . a form of construction. Shown is in [0006] Within the framework of the submitted inven- tion it became clear that the symmetrical arrangement Fig. 1 side view of an armoured vehicle with of the wheels on both sides of the vehicle with torsion so tracks and a pair of steerable wheels bars is only possible if the torsion bars do not stretch across the entire width of the hull from the swing arms Fig. 2 schematic drawing of the drive system along the rotary axis. At least one torsion bar section of of an armoured vehicle according to each sprung wheel must be staggered to the swinging Fig. 1 axis of the swing arm connected to it for load transmis- ss sion, especially in a positive- or possibly non-positive- Fig. 3 schematic drawing of the springing of locking way. In order to spring the swing arm over a suf- the road and idler wheels ficiently large swinging area, the preferred solution

2 3 EP 0 937 634 A1 4

Fig. 4 schematic drawing of a springing with anchored thereto. In order to protect the torsion bar sec- three torsion bar sections. tions 17, 20 and especially to increase the stability of the hull, preferably transversal walls 24 are installed in Fig. 5 and 6 schematic drawings of an idler wheel front of and behind each of the associated torsion bar springing 5 sections 1 7, 20. The transversal walls 24 are firmly con- nected to the dividing wall 19 and the side walls of the Fig. 7 horizontal section through a swing arm hull 2. The chamber structure thus formed ensures an for an idler wheel springing extremely high torsional and distortion rigidity of the hull area with the torsion bars. Fig. 8 a section of a side view of a swing arm 10 [0015] Fig. 4 shows a specific construction where an for an idler wheel springing idler wheel 5 is sprung by three torsion bar sections 1 7, 20, 20'. The second torsion bar section 20 is not firmly Fig. 9 a side view of a swing arm with a shock anti-torsional anchored to the bearing box 23, but is absorber located between it and the mounted in a pivot bearing 1 8 and is connected to a fur- hull. 15 ther torsion bar section 20' via a gear system 21 . This further and last torsion bar section 20' is firmly anti-tor- [0011] Fig. 1 shows an armoured vehicle 1 with a hull sional anchored to the gear case 22. 2 and an armed turret 3. Each of the tracks 4 run around [0016] It is obvious that to increase and change the three road wheels 5, an idler wheel 6 and a sprocket swinging capacity of the swing arms 16, also more than drive 7. A pair of steerable front wheels 8 are located in 20 two or three torsion bar sections can be connected to the front area of the hull 2. one another in series or that the torsion bar sections [0012] According to Fig. 2, the tractive effort of an connected together can have varying spring character- engine 9 is transmitted via a gear unit 11a and a main istics. Moreover, it is also an option that the torsion bar shaft 10 to a transfer unit 11b propelling the sprocket sections 1 7, 20 are not arranged symmetrically to two drive 7 attached to a track drive 12. The pair of front 25 wheels located opposite each other. For example, a tor- wheels 8 are propelled by the transfer unit 11b via a sion bar section which is connected to the swing arm of system 13. The hull being formed as a a left or accordingly of a right wheel is located in front of flotable body, hydraulic propeller drives 14 are provided. or behind the swinging axis, respectively. The torsion Preferably, a hydraulic winch 15 is installed at the front bar sections differently staggered to the swinging axis of of the hull 2. 30 the right and left swing arm could also stretch across the [001 3] Fig. 3 shows a form of construction of the sus- entire width of the hull, and second torsion bar sections pension of the road wheels 5 and the track idler wheels could be omitted. Furthermore, the gear systems 21 6 formed as double wheels. These double wheels 5 and could be designed so that the second torsion bar sec- 6 are pivoted at the free end of the swing arms 16 and tion runs diagonally, especially orthogonally to the first. 16'. The swing arms 16, 16' are firmly connected to the 35 [001 7] Fig. 5 shows a swing arm 1 1 6 where the pivot first torsion bar sections 1 7, each being pivoted at both bearing 26 of the idler wheel 6 attached to it is moved their ends in rotary bearings 18. The first torsion bar relative to the swing arm 116 both with the rotating sections 1 7 stretch along the swinging axis of the swing motion around the axis of the torsion bar section 1 7 as arm 1 6, 1 6' to a vertical medium plane 1 9a of the hull 2. well as with a compensation device 25. Thereby the In front of the medium plane 19a, the first torsion bar 40 pivot movement and the compensation movement sections 1 7 are each pivotally connected to the first end should be so coupled that the pivot bearing 26 is essen- areas of second torsion bar sections 20. Said second tially moved vertically at angles of traverse 27 in a deter- sections 20 preferably run parallel to the first sections, mined field of traverse and that the horizontal position of are located in rotary bearings 18' at the first end areas the pivot bearing 26 essentially remains constant. In this and firmly anti-torsional anchored to the hull 2 at their 45 way it can be prevented that the track tension changes second end areas. owing to axis movements of the idler wheel 6. This is of [001 4] The torsion bar sections 1 7 and 20 adjacent to particular importance when the idler wheel 6 is also one another are connected to each other via spur-gear employed as road wheel. If the load deflection of road systems 21. The gear systems 21 are preferably each wheels 5 (Fig. 1) should essentially be vertical, then the installed in a gear case 22, whereby the gear cases 22 so road wheels 5 can be provided with compensation are anchored particularly on both sides to a vertical devices 25. dividing wall 19 in the area of the medium plane 19a of [0018] Fig. 6 shows a compensation device 25, which the hull 2. A preferred form of construction makes provi- moves the pivot bearing 26 corresponding to the prevail- sion for a bearing box 23 to be mounted at the swing ing angle of traverse 27 to a spherical position 29 of the arm 16, 16' on the outer wall of the hull 2. The first tor- 55 compensation device 25, whereby the horizontal com- sion bar sections 1 7 are connected to said bearing box ponents of the pivoting and compensation movements 23 in pivot bearings 1 8 and the second ends of the sec- essentially neutralise one another. The movement of ond torsion bar sections are firmly anti-torsional the pivot bearing 26 resulting from the overlapping of

3 5 EP 0 937 634 A1 6 the pivoting and compensation movements corre- driving characteristics, it is advantageous to dampen sponds to a cycloid and can be effected especially for the movement of the swing arms of all the road wheels example with an epicyclic gear. with shock aborbers 41 . [001 9] Fig. 7 shows a specific construction of the com- pensation device 25 in which the swing arm 116 pivots s Claims around the axis of the torsion bar section 1 7 and com- prises a compensation circular shaft 1 1 6a around which 1. Vehicle (1) with a hull (2) to which on the right and the pivot bearing 26 and a bearing shaft 26' rotates. The left a track (4) each is provided running over at least bearing shaft 26' protrudes eccentrically from a disk. In three wheels (5, 6), said wheels (5, 6) are pivoted order to couple the motion of the swing arm with the to on wheel bearings with swing arms (16, 16'), rotation of the bearing shaft 26', the position of the whereby torsion bars (1 7, 20) are provided to spring swing arm 1 1 6 is transmitted to the disk 34 via a first the movement of the swing arms (16, 16') around bevel gearing 30, a first shaft 31 pivoted in the swing the swinging axis of said swing arms (16, 16'), char- arm 1 16, a second bevel gearing 32 and an adjustable acterised in that at least one torsion bar (20) of gear 33. The first bevel gearing 30 comprises a first 15 each sprung wheel (5, 6) firmly anti-torsional gear 30a firmly anchored to the hull 2 and a second anchored to a swing arm (1 6, 1 6') runs staggered to bevel gear 30b attached to the first shaft 31 . The adjust- the swinging axis of this swing arm (16, 16'). able gear 33 is connected to an adjustable locking gear 37 via a third bevel gearing 35 and a second shaft 36 2. Vehicle according to claim 1 , characterised in that pivoted in the swing arm 116. With the adjustable gear 20 the swinging axis of pairs of wheels (5, 6) located 33, a desired allotment of the angle of traverse 27 and opposite one another on the left and right of the hull the spherical position 29 (Fig. 6) can be set and fixed on are in alignment. the locking gear 37. Hence, the locking gear 37 enables a point of the epicycle path of the pivot bearing 26 to be 3. Vehicle according to claim 1 or 2, characterised in adjusted around the axis of the torsion bar 1 7. 25 that each swing arm (16, 16') is provided with at [0020] Fig. 8 shows a section of the swing arm 116 least two torsion bar sections (17, 20) connected firmly connected to the first torsion bar section 1 7, the with each other, whereby a first torsion bar section second shaft 36 located therein and the adjustable lock- firmly connected to the swing arm (16, 16') ing gear 37. The locking gear 37 comprises interlocking stretches along the swinging axis of the swing arm parts 37a, 37b, which can be locked together in a 30 (1 6, 1 6') to a vertical medium plane (1 9a) of the hull desired rotary positioning of the second shaft 36. (2) and is pivotally connected, especially in a posi- Thereby, one of the two parts 37a, 37b is firmly con- tive-locking way, in front of the medium plane (19a) nected to the swing arm 1 16, and the other firmly anti- with the first end area of a second torsion bar sec- torsional anchored to the second shaft 36 but shiftable tion (20), said second section (20) preferably runs along the second shaft 36, especially via a form-locking 35 parallel to the first and at its second end is firmly many-sided profile 38. In order to press the two parts anti-torsional anchored to the hull (2). 37a, 37b to each other, provision is made for example for a double nut configuration 39 on a thread 40 of the 4. Vehicle according to claim 3, characterised in that second shaft 36. the torsion bar sections (17, 20) adjacent to one [0021] It stands to reason that the compensation 40 another are connected to each other via spur-gear device can also comprise - instead of an epicyclic gear- systems (21), said gear systems (21) are preferably ing - a pivot position determination and a positioning each installed in a gear case (22), whereby the gear device for positioning the pivot bearing on the swing arm cases (22) are anchored particularly on both sides corresponding to the determined pivot position. Further- to a vertical dividing wall (19) in the area of the more, also a guiding device could be located between 45 medium plane of the hull (2) running in the longitu- the hull and the swing arm so that the pivot bearing can dinal direction of the vehicle. essentially only be moved vertically. [0022] Fig. 9 shows a preferential embodiment in 5. Vehicle according to claim 3, characterized in that which the swing arms 1 6 of the road wheels are addi- bearing boxes (23) are mounted at the swing arm tionally connected to the hull 2 via shock absorb- so (16, 16') on the outer wall of the hull (2), whereby a ers/dampers 41 Each damper 41 is attached via swivel first torsion bar section (17) is connected to said connections 42, each swivelling at a swing arm 16 and bearing box (23) in a pivot bearing (1 8) and the sec- at the hull 2. Preferably, hydraulic dampers are used. ond end of the second torsion bar section (17) is The better driving characteristics in the case of uneven firmly anti-torsional anchored thereto. terrain known from vehicle construction and also a ss smaller dynamic stress of the torsion bar sections 17, 6. Vehicle according to one of the claims 3 to 5 char- 20 (Fig.3) are ensured as a result of employing shock acterized in that the torsion bar sections (17, 20) of absorbers. It has been shown that to achieve the better each wheel (5, 6) can be removed from and

4 7 EP 0 937 634 A1

inserted into the hull (2) independent of the suspen- sion or springing of another wheel (5, 6).

7. Vehicle according to one of the claims 1 to 6 char- acterized in that on both sides a wheel or double s wheel is designed as a track idler wheel (6) and three - if necessary more than three - wheels or double wheels are designed as road wheels (5), whereby the track idler wheels are preferably located at the rear track area end and hence in the 10 area of the rear of the vehicle, and the swing arms (16) of the road wheels (5) are preferably con- nected to the hull (2) via shock absorbers (41).

8. Vehicle according to claim 7 characterized in that at is least in the case of each track idler wheel (6) a com- pensation device (25) is provided between the swing arm (16', 116) and the pivot bearing (26) of the idler wheel (6) attached thereto, whereby said compensation device (25) overlaps the pivot move- 20 ment of the pivot bearing (26) around the axis of the first torsion bar section (17) with a compensation movement, whereby the pivot movement and the compensation movement are coupled so that, at angles of traverse in a determined field of traverse, 25 the pivot bearing (26) is essentially moved verti- cally, and the horizontal position of the pivot bearing (26) essentially remains constant.

9. Vehicle according to claim 8 characterised in that 30 the compensation device (25) comprises an epicy- clic gearing and an adjustable locking gear (37), whereby the locking gear (37) enables a point of the epicycle path of the pivot bearing (26) to be adjusted around the axis of the torsion bar (1 7). 35

10. Vehicle according to claims 1 to 9 characterised in that a track sprocket drive (7) is provided at the front track area end of each track, whereby a gear unit (11a) enables both sprocket drives (7) to be driven 40 the same and particularly also differently.

11. Vehicle according to the claims 1 to 10 character- ised in that a steerable and drivable pair of wheels (8) is provided in the area between the front track 45 area end and the front of the vehicle.

55 EP 0 937 634 A1 EP 0 937 634 A1 EP 0 937 634 A1 EP 0 937 634 A1

9 EP 0 937 634 A1

European Patent Number EUROPEAN SEARCH REPORT Application Office EP 98 10 3066

DOCUMENTS CONSIDERED TO BE RELEVANT Category Citation of document with indication, where appropriate. Relevant CLASSIFICATION OF THE of relevant passages to claim APPLICATION (lnt.CI.6) US 4 194 761 A (FALK ET AL.) 25 March 1980 1,2 B62D55/108 * abstract; figures 1,4,6 * 3 B60G11/18

DE 747 807 C (-) 1-5 * the whole document *

DE 19 28 961 A (PIETSCH) 17 December 1970 1-3 * claim 2; figure 2 *

DE 920 291 C (BORGWARD) * the whole document *

FR 2 544 259 A () 19 October 1984 * figure 1 *

"Lei enter Schutzenpanzerwagen" 7,10,11 WAFFEN REVUE. , vol . 58, 1985, NURNBERG DE, pages 9301-9352, XP002071835 * page 9330; figure 40 * TECHNICAL FIELDS SEARCHED FR 852 408 A (KRAUSS-MAFFEI ) 7,11 (lnt.CI.6) * the whole document * B62D B60G US 2 107 072 A (HERRINGT0N) 1 February 7,10,11 1938 * figures 1,2 *

The present search report has been drawn up for all claims Place of search Date of completion of the search Examiner BERLIN 16 July 1998 Krieger, P CATEGORY OF CITED DOCUMENTS theory or principle underlying the invention earlier patent document, but published on, c X : particularly relevant if taken alone after the filing date Y : particularly relevant if combined with another document cited in the application document of the same category document cited for other reasons A : technological background O : non-written disclosure & : member of the same patent family, corresponding P : intermediate document document

10 EP 0 937 634 A1

ANNEX TO THE EUROPEAN SEARCH REPORT ON EUROPEAN PATENT APPLICATION NO. EP 98 10 3066

This annex lists the patent family members relating to the patent documents cited in the above-mentioned European search report. The members are as contained in the European Patent Office EDP file on The European Patent Office is in no way liable for these particulars which are merely given for the purpose of information. 16-07-1998

Patent document Publication Patent family Publication cited in search report date member(s) date US 4194761 A 25-03-1980 SE 432568 B 09-04-1984 DE 2818226 A 23-11-1978 SE 7705890 A 19-11-1978

DE 747807 C NONE

DE 1928961 A 17-12-1970 DE 2303173 A 01-08-1974 DE 2043512 A 09-03-1972

DE 920291 C NONE

FR 2544259 A 19-10-1984 NONE

FR 852408 A NONE

US 2107072 A 01-02-1938 NONE

For more details about this annex : see Official Journal of the European Patent Office. No. 1 2/82

11