STEERING DEVICE FOR MANY-AXLED GOOSE-NECK TRAILERS

Abstract: A steering device for many-axled goose-neck trailers (2, 5) coupled behind a tractor (1) or other vehicles (5) via the goose-neck (3, 16) and a fifth wheel (4, 18) on the tractor (1) or other vehicle (5). Of the wheel sets of the trailer (2, 5) the foremost one (16, 18) and the rear ones (8a, 8b, 9a, 9b, 12a, 12b) are steered by friction against the road, and in addition thereto the rearmost ones (9a, 9b, 12a, 12b) of the rear wheel sets (8a, 8b, 9a, 9b, 12a, 12b) are also forcibly steered from the tractor (1) or other vehicle (5) by the fifth wheel (4, 18) of same via a transmission (48', 48''). The wheel sets may also be provided by a reverse lock (44).

Description: Steering device for many-axled goose-neck trailers This invention relates to a steering device.for many-axled goose-neck trailers which are coupled behind a tracking vehicle, behind another trailer or behind a dolly, the goose-neck of the trailer being coupled with a vehicle in front of it via a pivotable and tiltable disc which, when driving in curves, by means of a transmission forcibly steers the rear wheel set oppositely to the steering wheels of the tracking vehicle, so that the trailer is brought to follow, to a greatest possible extent, the track of the tracking vehicle. When a many-axled trailer is coupled behind a tracking vehicle or behind another trailer, accor¬ ding to the Road Authorities, such trains of vehicles, for safety reason, are only allowed to travel at limited speed, and the aim of the invention is to obtain that such vehicle- trains may also be allowed to drive at the maximum speed permitted for the road in question. According to the inven¬ tion this is obtained by that the front and rear wheels of the trailer, in a manner known per se, are steered by fric¬ tionagainst the road, and by that, in addition thereto, the rearmost friction-steered wheels are also forcibly steered through said transmission. When a train of vehicles, such as consisting of a tracking vehicle or tractor and two many-axled goose-neck trailers, the first coupled by its goose-neck to the tractor via a pivotable and tiltable disc - often called "the fifth wheel" - and the second trailer coupled with the first one in the same way or via a dolly coupled behind the first trailer and also provided with a fifth wheel, is driving along a road of first category (motor road) , the friction-steered wheel sets will safely bring both trailers to follow the track of the tractor. However, when the road is slippery or of a less high category, such as with a sandy pavement, the friction-steering may not function satisfactorily. In ■ ^SiΪEArt or d er to obtain full safety also under such dangerous conditions, according to the invention, the rearmost fric¬ tion-steered wheels are also forcibly steered. Consequently, the following benefits are obtained by the invention: 1. It is possible to drive with full speed corresponding to the road speed limits with one or more fully-loaded trailers behind one single tractor. 2. The pay-load can be substantially -increased. 3. Transportation of goods of exceptional length is possible without restriction of the speed. 4. The system results in double security on the road since the forcible steering of the friction-steered rear wheels will act even if the road is slippery and the friction-steering does not act alone. According to a further feature of the inyention one or more of the friction-steered sets of wheels are ., provided with a reverse lock which is controlled from the wheel house of the tractor. Thereby is obtained that the vehicle train may also be safely reversed. The invention is to be explained in the following with reference to the drawings in which: Fig. 1 shows a vehicle train as seen from the side, Fig. 2 shows the same vehicle tr.ain in plan view when driving in a sharp bend, and Fig. 3 shows one of the rear wheel bogies with steering device and reverse lock. In Fig. 1 and 2 is shown a vehicle train consisting a tractor 1 , behind which a many-axled goose-neck trailer 2 is coupled via its goose-neck 3 and a pivotable and tiltable disc 4, the fifth wheel, on the tractor.Behind said trailer 2 is connected a four-wheel dolly 15 which is also provided with a fifth wheel 18 to be connected with the goose-neck of a second many-axled goose-neck trailer 5. The first trailer 2 has eight axles and the rear trailer has six axles Of the wheel sets of the trailers 2 and 5 the first set 6 and 10, respectively, is steered by friction against the road, and so are also the rear wheel sets 8a, 8b, and 9a, 9b of trailer 2 and 12a and 12b of trailer 5. In addition thereto the rearmost wheel sets 9a, 9b and 12a, 12b, respec ¬ tively, are, as known per se, also forcibly steered from the respective fifth wheels 4 and 18 with which the goose¬ neck 3 and 16, respectively, are coupled. The three inter¬ mediate wheel sets of both trailers, namely 7a, 7b, 7c and 11a, 11b, 11c, respectively, are not steered. Fig. 1 shows an exceptionally long load 20 which via tiltable and pivotable discs 21 og 22 is carried by both trailers 2 and 5. In such case it is necessary to care for a telescopic coupling between the trailers 2 and 5 for en- abling the vehicle train to drive in curves. This teles¬ copic coupling is arranged in connection with the pull rod 17. of the dolly 15, the forward end of which is linked at 14 to the rear end of trailer 2. • * Fig. 2 shows the vehicle train when driving in a sharp bend. As will be seen the friction-steering and the forcible steering of the rear wheel sets 9a, 9b and 12a, 12b, respectively, will turn these wheel sets oppo¬ sitely in relation to the steering wheels of the tractor 1. The two other wheel sets 8a and 8b of trailer 2 will also be turned outwardly in the bend correspondingly by friction only. Consequently, the trailers will to a greatest possible extent be brought tofollow the track of the tractor 1. The parts 38, 43' and 43" in Fig.2 belong to the steering devices for the wheel sets 6, 8, 9, 10 and 12 and will be explained in detail below. Fig. 3 shows one of the rearmost wheel bogies 9a, 9b, 12a, 12b as seen in top plan view. The twin wheels 8' and 8" of the bogie are rotatable on axles 35' and 35" respectively. At the right side is also shown a brake drum 25 to which is fixed a twin wheel felly, not shown. Each axle 35' and 35" are rigidly connected with an arm 36' and 36" respectively, forming together with the axle an angle lever which is turnable about a king pin 34', 34", respectively, OMPI the bearing housings of which are numbered 33" and 33". Said housings are via forwardly directed extensions 32' and 32", respectively, of the main axle 31 fixedly con¬ nected with said axles 31. Since the kingpins 34' and 34", thus, are offset forwardly, i.e. in the driving direction (see arrow 51) in relation to the respective axles 35' and 35", and the angle levers 35',36' and 35",36" are linked to gether via a stay system 38', 38" and 40, the wheels 8' and 8" will always run parallelly steered by friction against the road. The link connections between the levers 35', 36* and 35", 36" and the stay rods 38* and 38", respectively, are numbered 37' and 37". The intermediate member 40 which is linked at 39' and 39" with the inner ends of the stay rods 38' and 38" has the form of a triangular plate, the rear corner of which has an extension 41 ' which is coupl with the midpoint of a double piston rod 42, the ends of which are connected with pistons located in hydraulic cy¬ linders 43' and 43", respectively. Said cylinders are via arms 43a' and 43a", respectively, supported by the fixed axle 31 of the bogie. By means of this hydraulic mechanic system 41, 42, 43', 43" the wheel set is forcibly steered by the respective fifth wheels 4 and 18 (Fig. 2) via hy¬ draulic connections 48' and 48". The triangular member 40 is also provided with a square opening 44 for a pin which is located behind said member and controlled by a pneumatic cylinder, not visible, to act as a reverse lock. By means of said lock the wheels 8' and 8" can be locked for travel in the forward and rearward direction only, the friction- steering being disengaged, so that the whole vehicle train may be safely reversed, when necessary. The pneumatic cylinder located behind the plate link 40 and operating the reverse lock, is controlled from the wheel house of the track 1 via an electro-mechanic connection 50. Fig. 3 shows the rearmost bogies, such as 9a, 9b of trailer 2 and 12a, 12b of trailer 5. The other bogies which are steered by friction only, such as 6, 8a and 8b of trailer 2 and 10 of trailer 5 are of the same construc¬ tion, except- that- the stay 38 (38', 38", 40) is rigid and in f OM one piece with the square opening arranged in the middle of same if said wheel set is to be locked when the vehicle train is to be reversed. Furthermore, the hydraulic mechanic forcible steering device 41, 42, 43', 3-", 43a', 43a", of course, is also missing. The wheels of the bogie are subjected to a down¬ ward pressure by two bellows 47' and 47" which serve, via two levers 46' and 46", to continuously keep the wheels 8' and 8" in contact with the road. The forward ends of said levers are pivotably connected with a transverse bar 45 fixed to the chassis of the trailer. Said levers carry the wheel axis 31. The rear end of said levers 46' and 46" is each fixed to one bellow 47' and 47", respectively, which are again fixed to the underside of the chassis. ' The pressure excerted by said bellows is automatically con¬ trolled by valves dependent on the load on the trailer. O PI

Claims: P a t e n t C l a i m s 1. Steering device for many-axled goose-neck trailer (2, 5) which is coupled behind a tracking vehicle (1) , behind another trailer (2) or behind a dolly (15), the goose-neck (3, 16) of the trailer being coupled with a vehicle in front of it via a pivotable and tiltable disc (4, 15) which, when driving in curves, by means of a transmission forcibly steers the rear wheel set oppositel to the steeling wheels of the trackling vehicle, so that the trailer is brought to follow, to the greatest possible extent, the track of the tracking vehicle, c h a r a c - t e r i z e d by that the front and rear wheels (6, 8a, 8b, 9a, 9b, 10, 12a, 12b) of the trailer (2, 5), in a manner known per se, are steered by friction against the road, and by that, in addition thereto, the rearmost friction-steered wheels (9a, 9b; 12a, 12b) are -also forcibly steered through said transmission. 2. Device as claiπed in claim 1, in which the trailer is eight-axled, c h a r a c t e r i z e d by that the front wheel set (6) and the four rear wheel sets (8a, 8b, 9a, 9b) are steered by friction and the two rearmost of the last- mentioned wheel sets are also forcibly steered. 3. Device as claimed in claim 1, in which the trailer is six-axled, c h a r a c t e r i z e d by that the front wheel set (10) and the two rear wheel sets (12a, 12b are friction-steered and said two last mentioned wheel set are also forcibly steered. 4. Device as claimed in claim 1, c h a r a c t e ¬ r i z e d by a reverse lock (44) which is controlled from the wheel house of the tracking vehicle (1) and which locks the steering of one or more of the friction-steered wheel sets (6, 10, 8a, 8b, 9a, 9b, 10, 12a, 12b) of the trailer (2, 5) during reversing. ■

Inventors: DAMM S
Applicants: DAMM SVERRE, DAMM S
Application year: 1981
Main classification: B62D13
IPC codes: B62D13, B62D53